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authorThomas Gleixner <tglx@linutronix.de>2011-05-20 20:06:24 +0200
committerThomas Gleixner <tglx@linutronix.de>2011-05-20 20:08:05 +0200
commit250f972d85effad5b6e10da4bbd877e6a4b503b6 (patch)
tree007393a6fc6439af7e0121dd99a6f9f9fb8405bc /kernel
parent7372b0b122af0f6675f3ab65bfd91c8a438e0480 (diff)
parentbbe7b8bef48c567f5ff3f6041c1fb011292e8f12 (diff)
Merge branch 'timers/urgent' into timers/core
Reason: Get upstream fixes and kfree_rcu which is necessary for a follow up patch. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'kernel')
-rw-r--r--kernel/Makefile6
-rw-r--r--kernel/capability.c12
-rw-r--r--kernel/cgroup.c27
-rw-r--r--kernel/cpuset.c2
-rw-r--r--kernel/cred.c12
-rw-r--r--kernel/events/Makefile6
-rw-r--r--kernel/events/core.c (renamed from kernel/perf_event.c)64
-rw-r--r--kernel/events/hw_breakpoint.c (renamed from kernel/hw_breakpoint.c)0
-rw-r--r--kernel/exit.c2
-rw-r--r--kernel/extable.c8
-rw-r--r--kernel/fork.c5
-rw-r--r--kernel/freezer.c4
-rw-r--r--kernel/hung_task.c2
-rw-r--r--kernel/irq/Kconfig4
-rw-r--r--kernel/irq/Makefile1
-rw-r--r--kernel/irq/chip.c3
-rw-r--r--kernel/irq/debug.h1
-rw-r--r--kernel/irq/generic-chip.c354
-rw-r--r--kernel/irq/irqdesc.c22
-rw-r--r--kernel/irq/manage.c3
-rw-r--r--kernel/irq/proc.c2
-rw-r--r--kernel/irq/settings.h17
-rw-r--r--kernel/jump_label.c539
-rw-r--r--kernel/kexec.c9
-rw-r--r--kernel/kmod.c16
-rw-r--r--kernel/ksysfs.c10
-rw-r--r--kernel/lockdep.c206
-rw-r--r--kernel/module.c105
-rw-r--r--kernel/mutex-debug.c2
-rw-r--r--kernel/mutex-debug.h2
-rw-r--r--kernel/mutex.c9
-rw-r--r--kernel/mutex.h2
-rw-r--r--kernel/params.c23
-rw-r--r--kernel/power/Kconfig10
-rw-r--r--kernel/power/hibernate.c58
-rw-r--r--kernel/power/main.c1
-rw-r--r--kernel/power/power.h4
-rw-r--r--kernel/power/snapshot.c33
-rw-r--r--kernel/power/suspend.c14
-rw-r--r--kernel/power/user.c5
-rw-r--r--kernel/ptrace.c17
-rw-r--r--kernel/rcupdate.c32
-rw-r--r--kernel/rcutiny.c45
-rw-r--r--kernel/rcutiny_plugin.h203
-rw-r--r--kernel/rcutorture.c26
-rw-r--r--kernel/rcutree.c526
-rw-r--r--kernel/rcutree.h104
-rw-r--r--kernel/rcutree_plugin.h568
-rw-r--r--kernel/rcutree_trace.c180
-rw-r--r--kernel/sched.c1658
-rw-r--r--kernel/sched_debug.c6
-rw-r--r--kernel/sched_fair.c126
-rw-r--r--kernel/sched_features.h6
-rw-r--r--kernel/sched_idletask.c2
-rw-r--r--kernel/sched_rt.c83
-rw-r--r--kernel/sched_stoptask.c5
-rw-r--r--kernel/softirq.c2
-rw-r--r--kernel/sys.c5
-rw-r--r--kernel/time/clockevents.c64
-rw-r--r--kernel/time/clocksource.c42
-rw-r--r--kernel/time/tick-broadcast.c12
-rw-r--r--kernel/trace/ftrace.c1261
-rw-r--r--kernel/trace/trace.c16
-rw-r--r--kernel/trace/trace.h2
-rw-r--r--kernel/trace/trace_events.c1
-rw-r--r--kernel/trace/trace_functions.c2
-rw-r--r--kernel/trace/trace_irqsoff.c1
-rw-r--r--kernel/trace/trace_kprobe.c1
-rw-r--r--kernel/trace/trace_output.c3
-rw-r--r--kernel/trace/trace_printk.c120
-rw-r--r--kernel/trace/trace_sched_wakeup.c1
-rw-r--r--kernel/trace/trace_selftest.c214
-rw-r--r--kernel/trace/trace_selftest_dynamic.c6
-rw-r--r--kernel/trace/trace_stack.c1
-rw-r--r--kernel/tracepoint.c23
75 files changed, 4643 insertions, 2326 deletions
diff --git a/kernel/Makefile b/kernel/Makefile
index 85cbfb31e73..e9cf19155b4 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -21,7 +21,6 @@ CFLAGS_REMOVE_mutex-debug.o = -pg
CFLAGS_REMOVE_rtmutex-debug.o = -pg
CFLAGS_REMOVE_cgroup-debug.o = -pg
CFLAGS_REMOVE_sched_clock.o = -pg
-CFLAGS_REMOVE_perf_event.o = -pg
CFLAGS_REMOVE_irq_work.o = -pg
endif
@@ -103,8 +102,9 @@ obj-$(CONFIG_RING_BUFFER) += trace/
obj-$(CONFIG_TRACEPOINTS) += trace/
obj-$(CONFIG_SMP) += sched_cpupri.o
obj-$(CONFIG_IRQ_WORK) += irq_work.o
-obj-$(CONFIG_PERF_EVENTS) += perf_event.o
-obj-$(CONFIG_HAVE_HW_BREAKPOINT) += hw_breakpoint.o
+
+obj-$(CONFIG_PERF_EVENTS) += events/
+
obj-$(CONFIG_USER_RETURN_NOTIFIER) += user-return-notifier.o
obj-$(CONFIG_PADATA) += padata.o
obj-$(CONFIG_CRASH_DUMP) += crash_dump.o
diff --git a/kernel/capability.c b/kernel/capability.c
index bf0c734d0c1..32a80e08ff4 100644
--- a/kernel/capability.c
+++ b/kernel/capability.c
@@ -399,3 +399,15 @@ bool task_ns_capable(struct task_struct *t, int cap)
return ns_capable(task_cred_xxx(t, user)->user_ns, cap);
}
EXPORT_SYMBOL(task_ns_capable);
+
+/**
+ * nsown_capable - Check superior capability to one's own user_ns
+ * @cap: The capability in question
+ *
+ * Return true if the current task has the given superior capability
+ * targeted at its own user namespace.
+ */
+bool nsown_capable(int cap)
+{
+ return ns_capable(current_user_ns(), cap);
+}
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 25c7eb52de1..909a35510af 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -326,12 +326,6 @@ static struct hlist_head *css_set_hash(struct cgroup_subsys_state *css[])
return &css_set_table[index];
}
-static void free_css_set_rcu(struct rcu_head *obj)
-{
- struct css_set *cg = container_of(obj, struct css_set, rcu_head);
- kfree(cg);
-}
-
/* We don't maintain the lists running through each css_set to its
* task until after the first call to cgroup_iter_start(). This
* reduces the fork()/exit() overhead for people who have cgroups
@@ -375,7 +369,7 @@ static void __put_css_set(struct css_set *cg, int taskexit)
}
write_unlock(&css_set_lock);
- call_rcu(&cg->rcu_head, free_css_set_rcu);
+ kfree_rcu(cg, rcu_head);
}
/*
@@ -812,13 +806,6 @@ static int cgroup_call_pre_destroy(struct cgroup *cgrp)
return ret;
}
-static void free_cgroup_rcu(struct rcu_head *obj)
-{
- struct cgroup *cgrp = container_of(obj, struct cgroup, rcu_head);
-
- kfree(cgrp);
-}
-
static void cgroup_diput(struct dentry *dentry, struct inode *inode)
{
/* is dentry a directory ? if so, kfree() associated cgroup */
@@ -856,7 +843,7 @@ static void cgroup_diput(struct dentry *dentry, struct inode *inode)
*/
BUG_ON(!list_empty(&cgrp->pidlists));
- call_rcu(&cgrp->rcu_head, free_cgroup_rcu);
+ kfree_rcu(cgrp, rcu_head);
}
iput(inode);
}
@@ -4623,14 +4610,6 @@ bool css_is_ancestor(struct cgroup_subsys_state *child,
return ret;
}
-static void __free_css_id_cb(struct rcu_head *head)
-{
- struct css_id *id;
-
- id = container_of(head, struct css_id, rcu_head);
- kfree(id);
-}
-
void free_css_id(struct cgroup_subsys *ss, struct cgroup_subsys_state *css)
{
struct css_id *id = css->id;
@@ -4645,7 +4624,7 @@ void free_css_id(struct cgroup_subsys *ss, struct cgroup_subsys_state *css)
spin_lock(&ss->id_lock);
idr_remove(&ss->idr, id->id);
spin_unlock(&ss->id_lock);
- call_rcu(&id->rcu_head, __free_css_id_cb);
+ kfree_rcu(id, rcu_head);
}
EXPORT_SYMBOL_GPL(free_css_id);
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 33eee16addb..2bb8c2e98ff 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -1159,7 +1159,7 @@ int current_cpuset_is_being_rebound(void)
static int update_relax_domain_level(struct cpuset *cs, s64 val)
{
#ifdef CONFIG_SMP
- if (val < -1 || val >= SD_LV_MAX)
+ if (val < -1 || val >= sched_domain_level_max)
return -EINVAL;
#endif
diff --git a/kernel/cred.c b/kernel/cred.c
index 5557b55048d..8093c16b84b 100644
--- a/kernel/cred.c
+++ b/kernel/cred.c
@@ -54,6 +54,7 @@ struct cred init_cred = {
.cap_effective = CAP_INIT_EFF_SET,
.cap_bset = CAP_INIT_BSET,
.user = INIT_USER,
+ .user_ns = &init_user_ns,
.group_info = &init_groups,
#ifdef CONFIG_KEYS
.tgcred = &init_tgcred,
@@ -410,6 +411,11 @@ int copy_creds(struct task_struct *p, unsigned long clone_flags)
goto error_put;
}
+ /* cache user_ns in cred. Doesn't need a refcount because it will
+ * stay pinned by cred->user
+ */
+ new->user_ns = new->user->user_ns;
+
#ifdef CONFIG_KEYS
/* new threads get their own thread keyrings if their parent already
* had one */
@@ -741,12 +747,6 @@ int set_create_files_as(struct cred *new, struct inode *inode)
}
EXPORT_SYMBOL(set_create_files_as);
-struct user_namespace *current_user_ns(void)
-{
- return _current_user_ns();
-}
-EXPORT_SYMBOL(current_user_ns);
-
#ifdef CONFIG_DEBUG_CREDENTIALS
bool creds_are_invalid(const struct cred *cred)
diff --git a/kernel/events/Makefile b/kernel/events/Makefile
new file mode 100644
index 00000000000..1ce23d3d839
--- /dev/null
+++ b/kernel/events/Makefile
@@ -0,0 +1,6 @@
+ifdef CONFIG_FUNCTION_TRACER
+CFLAGS_REMOVE_core.o = -pg
+endif
+
+obj-y := core.o
+obj-$(CONFIG_HAVE_HW_BREAKPOINT) += hw_breakpoint.o
diff --git a/kernel/perf_event.c b/kernel/events/core.c
index 8e81a9860a0..c09767f7db3 100644
--- a/kernel/perf_event.c
+++ b/kernel/events/core.c
@@ -2,8 +2,8 @@
* Performance events core code:
*
* Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de>
- * Copyright (C) 2008-2009 Red Hat, Inc., Ingo Molnar
- * Copyright (C) 2008-2009 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
+ * Copyright (C) 2008-2011 Red Hat, Inc., Ingo Molnar
+ * Copyright (C) 2008-2011 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
* Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
*
* For licensing details see kernel-base/COPYING
@@ -39,10 +39,10 @@
#include <asm/irq_regs.h>
struct remote_function_call {
- struct task_struct *p;
- int (*func)(void *info);
- void *info;
- int ret;
+ struct task_struct *p;
+ int (*func)(void *info);
+ void *info;
+ int ret;
};
static void remote_function(void *data)
@@ -76,10 +76,10 @@ static int
task_function_call(struct task_struct *p, int (*func) (void *info), void *info)
{
struct remote_function_call data = {
- .p = p,
- .func = func,
- .info = info,
- .ret = -ESRCH, /* No such (running) process */
+ .p = p,
+ .func = func,
+ .info = info,
+ .ret = -ESRCH, /* No such (running) process */
};
if (task_curr(p))
@@ -100,10 +100,10 @@ task_function_call(struct task_struct *p, int (*func) (void *info), void *info)
static int cpu_function_call(int cpu, int (*func) (void *info), void *info)
{
struct remote_function_call data = {
- .p = NULL,
- .func = func,
- .info = info,
- .ret = -ENXIO, /* No such CPU */
+ .p = NULL,
+ .func = func,
+ .info = info,
+ .ret = -ENXIO, /* No such CPU */
};
smp_call_function_single(cpu, remote_function, &data, 1);
@@ -125,7 +125,7 @@ enum event_type_t {
* perf_sched_events : >0 events exist
* perf_cgroup_events: >0 per-cpu cgroup events exist on this cpu
*/
-atomic_t perf_sched_events __read_mostly;
+struct jump_label_key perf_sched_events __read_mostly;
static DEFINE_PER_CPU(atomic_t, perf_cgroup_events);
static atomic_t nr_mmap_events __read_mostly;
@@ -586,14 +586,6 @@ static void get_ctx(struct perf_event_context *ctx)
WARN_ON(!atomic_inc_not_zero(&ctx->refcount));
}
-static void free_ctx(struct rcu_head *head)
-{
- struct perf_event_context *ctx;
-
- ctx = container_of(head, struct perf_event_context, rcu_head);
- kfree(ctx);
-}
-
static void put_ctx(struct perf_event_context *ctx)
{
if (atomic_dec_and_test(&ctx->refcount)) {
@@ -601,7 +593,7 @@ static void put_ctx(struct perf_event_context *ctx)
put_ctx(ctx->parent_ctx);
if (ctx->task)
put_task_struct(ctx->task);
- call_rcu(&ctx->rcu_head, free_ctx);
+ kfree_rcu(ctx, rcu_head);
}
}
@@ -5331,14 +5323,6 @@ swevent_hlist_deref(struct swevent_htable *swhash)
lockdep_is_held(&swhash->hlist_mutex));
}
-static void swevent_hlist_release_rcu(struct rcu_head *rcu_head)
-{
- struct swevent_hlist *hlist;
-
- hlist = container_of(rcu_head, struct swevent_hlist, rcu_head);
- kfree(hlist);
-}
-
static void swevent_hlist_release(struct swevent_htable *swhash)
{
struct swevent_hlist *hlist = swevent_hlist_deref(swhash);
@@ -5347,7 +5331,7 @@ static void swevent_hlist_release(struct swevent_htable *swhash)
return;
rcu_assign_pointer(swhash->swevent_hlist, NULL);
- call_rcu(&hlist->rcu_head, swevent_hlist_release_rcu);
+ kfree_rcu(hlist, rcu_head);
}
static void swevent_hlist_put_cpu(struct perf_event *event, int cpu)
@@ -5429,7 +5413,7 @@ fail:
return err;
}
-atomic_t perf_swevent_enabled[PERF_COUNT_SW_MAX];
+struct jump_label_key perf_swevent_enabled[PERF_COUNT_SW_MAX];
static void sw_perf_event_destroy(struct perf_event *event)
{
@@ -7445,11 +7429,11 @@ static void perf_cgroup_exit(struct cgroup_subsys *ss, struct cgroup *cgrp,
}
struct cgroup_subsys perf_subsys = {
- .name = "perf_event",
- .subsys_id = perf_subsys_id,
- .create = perf_cgroup_create,
- .destroy = perf_cgroup_destroy,
- .exit = perf_cgroup_exit,
- .attach = perf_cgroup_attach,
+ .name = "perf_event",
+ .subsys_id = perf_subsys_id,
+ .create = perf_cgroup_create,
+ .destroy = perf_cgroup_destroy,
+ .exit = perf_cgroup_exit,
+ .attach = perf_cgroup_attach,
};
#endif /* CONFIG_CGROUP_PERF */
diff --git a/kernel/hw_breakpoint.c b/kernel/events/hw_breakpoint.c
index 086adf25a55..086adf25a55 100644
--- a/kernel/hw_breakpoint.c
+++ b/kernel/events/hw_breakpoint.c
diff --git a/kernel/exit.c b/kernel/exit.c
index f5d2f63bae0..8dd87418154 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -1016,7 +1016,7 @@ NORET_TYPE void do_exit(long code)
/*
* FIXME: do that only when needed, using sched_exit tracepoint
*/
- flush_ptrace_hw_breakpoint(tsk);
+ ptrace_put_breakpoints(tsk);
exit_notify(tsk, group_dead);
#ifdef CONFIG_NUMA
diff --git a/kernel/extable.c b/kernel/extable.c
index 7f8f263f852..c2d625fcda7 100644
--- a/kernel/extable.c
+++ b/kernel/extable.c
@@ -72,6 +72,14 @@ int core_kernel_text(unsigned long addr)
return 0;
}
+int core_kernel_data(unsigned long addr)
+{
+ if (addr >= (unsigned long)_sdata &&
+ addr < (unsigned long)_edata)
+ return 1;
+ return 0;
+}
+
int __kernel_text_address(unsigned long addr)
{
if (core_kernel_text(addr))
diff --git a/kernel/fork.c b/kernel/fork.c
index e7548dee636..2b44d82b823 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1103,7 +1103,6 @@ static struct task_struct *copy_process(unsigned long clone_flags,
posix_cpu_timers_init(p);
- p->lock_depth = -1; /* -1 = no lock */
do_posix_clock_monotonic_gettime(&p->start_time);
p->real_start_time = p->start_time;
monotonic_to_bootbased(&p->real_start_time);
@@ -1153,7 +1152,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
#endif
/* Perform scheduler related setup. Assign this task to a CPU. */
- sched_fork(p, clone_flags);
+ sched_fork(p);
retval = perf_event_init_task(p);
if (retval)
@@ -1464,7 +1463,7 @@ long do_fork(unsigned long clone_flags,
*/
p->flags &= ~PF_STARTING;
- wake_up_new_task(p, clone_flags);
+ wake_up_new_task(p);
tracehook_report_clone_complete(trace, regs,
clone_flags, nr, p);
diff --git a/kernel/freezer.c b/kernel/freezer.c
index 66ecd2ead21..7b01de98bb6 100644
--- a/kernel/freezer.c
+++ b/kernel/freezer.c
@@ -17,7 +17,7 @@ static inline void frozen_process(void)
{
if (!unlikely(current->flags & PF_NOFREEZE)) {
current->flags |= PF_FROZEN;
- wmb();
+ smp_wmb();
}
clear_freeze_flag(current);
}
@@ -93,7 +93,7 @@ bool freeze_task(struct task_struct *p, bool sig_only)
* the task as frozen and next clears its TIF_FREEZE.
*/
if (!freezing(p)) {
- rmb();
+ smp_rmb();
if (frozen(p))
return false;
diff --git a/kernel/hung_task.c b/kernel/hung_task.c
index 53ead174da2..ea640120ab8 100644
--- a/kernel/hung_task.c
+++ b/kernel/hung_task.c
@@ -33,7 +33,7 @@ unsigned long __read_mostly sysctl_hung_task_check_count = PID_MAX_LIMIT;
/*
* Zero means infinite timeout - no checking done:
*/
-unsigned long __read_mostly sysctl_hung_task_timeout_secs = 120;
+unsigned long __read_mostly sysctl_hung_task_timeout_secs = CONFIG_DEFAULT_HUNG_TASK_TIMEOUT;
unsigned long __read_mostly sysctl_hung_task_warnings = 10;
diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig
index c574f9a12c4..d1d051b38e0 100644
--- a/kernel/irq/Kconfig
+++ b/kernel/irq/Kconfig
@@ -48,6 +48,10 @@ config IRQ_PREFLOW_FASTEOI
config IRQ_EDGE_EOI_HANDLER
bool
+# Generic configurable interrupt chip implementation
+config GENERIC_IRQ_CHIP
+ bool
+
# Support forced irq threading
config IRQ_FORCED_THREADING
bool
diff --git a/kernel/irq/Makefile b/kernel/irq/Makefile
index 54329cd7b3e..73290056cfb 100644
--- a/kernel/irq/Makefile
+++ b/kernel/irq/Makefile
@@ -1,5 +1,6 @@
obj-y := irqdesc.o handle.o manage.o spurious.o resend.o chip.o dummychip.o devres.o
+obj-$(CONFIG_GENERIC_IRQ_CHIP) += generic-chip.o
obj-$(CONFIG_GENERIC_IRQ_PROBE) += autoprobe.o
obj-$(CONFIG_PROC_FS) += proc.o
obj-$(CONFIG_GENERIC_PENDING_IRQ) += migration.o
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index 4af1e2b244c..d5a3009da71 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -310,6 +310,7 @@ handle_simple_irq(unsigned int irq, struct irq_desc *desc)
out_unlock:
raw_spin_unlock(&desc->lock);
}
+EXPORT_SYMBOL_GPL(handle_simple_irq);
/**
* handle_level_irq - Level type irq handler
@@ -573,6 +574,7 @@ __irq_set_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
if (handle != handle_bad_irq && is_chained) {
irq_settings_set_noprobe(desc);
irq_settings_set_norequest(desc);
+ irq_settings_set_nothread(desc);
irq_startup(desc);
}
out:
@@ -612,6 +614,7 @@ void irq_modify_status(unsigned int irq, unsigned long clr, unsigned long set)
irq_put_desc_unlock(desc, flags);
}
+EXPORT_SYMBOL_GPL(irq_modify_status);
/**
* irq_cpu_online - Invoke all irq_cpu_online functions.
diff --git a/kernel/irq/debug.h b/kernel/irq/debug.h
index 306cba37e9a..97a8bfadc88 100644
--- a/kernel/irq/debug.h
+++ b/kernel/irq/debug.h
@@ -27,6 +27,7 @@ static inline void print_irq_desc(unsigned int irq, struct irq_desc *desc)
P(IRQ_PER_CPU);
P(IRQ_NOPROBE);
P(IRQ_NOREQUEST);
+ P(IRQ_NOTHREAD);
P(IRQ_NOAUTOEN);
PS(IRQS_AUTODETECT);
diff --git a/kernel/irq/generic-chip.c b/kernel/irq/generic-chip.c
new file mode 100644
index 00000000000..31a9db71190
--- /dev/null
+++ b/kernel/irq/generic-chip.c
@@ -0,0 +1,354 @@
+/*
+ * Library implementing the most common irq chip callback functions
+ *
+ * Copyright (C) 2011, Thomas Gleixner
+ */
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/kernel_stat.h>
+#include <linux/syscore_ops.h>
+
+#include "internals.h"
+
+static LIST_HEAD(gc_list);
+static DEFINE_RAW_SPINLOCK(gc_lock);
+
+static inline struct irq_chip_regs *cur_regs(struct irq_data *d)
+{
+ return &container_of(d->chip, struct irq_chip_type, chip)->regs;
+}
+
+/**
+ * irq_gc_noop - NOOP function
+ * @d: irq_data
+ */
+void irq_gc_noop(struct irq_data *d)
+{
+}
+
+/**
+ * irq_gc_mask_disable_reg - Mask chip via disable register
+ * @d: irq_data
+ *
+ * Chip has separate enable/disable registers instead of a single mask
+ * register.
+ */
+void irq_gc_mask_disable_reg(struct irq_data *d)
+{
+ struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
+ u32 mask = 1 << (d->irq - gc->irq_base);
+
+ irq_gc_lock(gc);
+ irq_reg_writel(mask, gc->reg_base + cur_regs(d)->disable);
+ gc->mask_cache &= ~mask;
+ irq_gc_unlock(gc);
+}
+
+/**
+ * irq_gc_mask_set_mask_bit - Mask chip via setting bit in mask register
+ * @d: irq_data
+ *
+ * Chip has a single mask register. Values of this register are cached
+ * and protected by gc->lock
+ */
+void irq_gc_mask_set_bit(struct irq_data *d)
+{
+ struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
+ u32 mask = 1 << (d->irq - gc->irq_base);
+
+ irq_gc_lock(gc);
+ gc->mask_cache |= mask;
+ irq_reg_writel(gc->mask_cache, gc->reg_base + cur_regs(d)->mask);
+ irq_gc_unlock(gc);
+}
+
+/**
+ * irq_gc_mask_set_mask_bit - Mask chip via clearing bit in mask register
+ * @d: irq_data
+ *
+ * Chip has a single mask register. Values of this register are cached
+ * and protected by gc->lock
+ */
+void irq_gc_mask_clr_bit(struct irq_data *d)
+{
+ struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
+ u32 mask = 1 << (d->irq - gc->irq_base);
+
+ irq_gc_lock(gc);
+ gc->mask_cache &= ~mask;
+ irq_reg_writel(gc->mask_cache, gc->reg_base + cur_regs(d)->mask);
+ irq_gc_unlock(gc);
+}
+
+/**
+ * irq_gc_unmask_enable_reg - Unmask chip via enable register
+ * @d: irq_data
+ *
+ * Chip has separate enable/disable registers instead of a single mask
+ * register.
+ */
+void irq_gc_unmask_enable_reg(struct irq_data *d)
+{
+ struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
+ u32 mask = 1 << (d->irq - gc->irq_base);
+
+ irq_gc_lock(gc);
+ irq_reg_writel(mask, gc->reg_base + cur_regs(d)->enable);
+ gc->mask_cache |= mask;
+ irq_gc_unlock(gc);
+}
+
+/**
+ * irq_gc_ack - Ack pending interrupt
+ * @d: irq_data
+ */
+void irq_gc_ack(struct irq_data *d)
+{
+ struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
+ u32 mask = 1 << (d->irq - gc->irq_base);
+
+ irq_gc_lock(gc);
+ irq_reg_writel(mask, gc->reg_base + cur_regs(d)->ack);
+ irq_gc_unlock(gc);
+}
+
+/**
+ * irq_gc_mask_disable_reg_and_ack- Mask and ack pending interrupt
+ * @d: irq_data
+ */
+void irq_gc_mask_disable_reg_and_ack(struct irq_data *d)
+{
+ struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
+ u32 mask = 1 << (d->irq - gc->irq_base);
+
+ irq_gc_lock(gc);
+ irq_reg_writel(mask, gc->reg_base + cur_regs(d)->mask);
+ irq_reg_writel(mask, gc->reg_base + cur_regs(d)->ack);
+ irq_gc_unlock(gc);
+}
+
+/**
+ * irq_gc_eoi - EOI interrupt
+ * @d: irq_data
+ */
+void irq_gc_eoi(struct irq_data *d)
+{
+ struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
+ u32 mask = 1 << (d->irq - gc->irq_base);
+
+ irq_gc_lock(gc);
+ irq_reg_writel(mask, gc->reg_base + cur_regs(d)->eoi);
+ irq_gc_unlock(gc);
+}
+
+/**
+ * irq_gc_set_wake - Set/clr wake bit for an interrupt
+ * @d: irq_data
+ *
+ * For chips where the wake from suspend functionality is not
+ * configured in a separate register and the wakeup active state is
+ * just stored in a bitmask.
+ */
+int irq_gc_set_wake(struct irq_data *d, unsigned int on)
+{
+ struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
+ u32 mask = 1 << (d->irq - gc->irq_base);
+
+ if (!(mask & gc->wake_enabled))
+ return -EINVAL;
+
+ irq_gc_lock(gc);
+ if (on)
+ gc->wake_active |= mask;
+ else
+ gc->wake_active &= ~mask;
+ irq_gc_unlock(gc);
+ return 0;
+}
+
+/**
+ * irq_alloc_generic_chip - Allocate a generic chip and initialize it
+ * @name: Name of the irq chip
+ * @num_ct: Number of irq_chip_type instances associated with this
+ * @irq_base: Interrupt base nr for this chip
+ * @reg_base: Register base address (virtual)
+ * @handler: Default flow handler associated with this chip
+ *
+ * Returns an initialized irq_chip_generic structure. The chip defaults
+ * to the primary (index 0) irq_chip_type and @handler
+ */
+struct irq_chip_generic *
+irq_alloc_generic_chip(const char *name, int num_ct, unsigned int irq_base,
+ void __iomem *reg_base, irq_flow_handler_t handler)
+{
+ struct irq_chip_generic *gc;
+ unsigned long sz = sizeof(*gc) + num_ct * sizeof(struct irq_chip_type);
+
+ gc = kzalloc(sz, GFP_KERNEL);
+ if (gc) {
+ raw_spin_lock_init(&gc->lock);
+ gc->num_ct = num_ct;
+ gc->irq_base = irq_base;
+ gc->reg_base = reg_base;
+ gc->chip_types->chip.name = name;
+ gc->chip_types->handler = handler;
+ }
+ return gc;
+}
+
+/*
+ * Separate lockdep class for interrupt chip which can nest irq_desc
+ * lock.
+ */
+static struct lock_class_key irq_nested_lock_class;
+
+/**
+ * irq_setup_generic_chip - Setup a range of interrupts with a generic chip
+ * @gc: Generic irq chip holding all data
+ * @msk: Bitmask holding the irqs to initialize relative to gc->irq_base
+ * @flags: Flags for initialization
+ * @clr: IRQ_* bits to clear
+ * @set: IRQ_* bits to set
+ *
+ * Set up max. 32 interrupts starting from gc->irq_base. Note, this
+ * initializes all interrupts to the primary irq_chip_type and its
+ * associated handler.
+ */
+void irq_setup_generic_chip(struct irq_chip_generic *gc, u32 msk,
+ enum irq_gc_flags flags, unsigned int clr,
+ unsigned int set)
+{
+ struct irq_chip_type *ct = gc->chip_types;
+ unsigned int i;
+
+ raw_spin_lock(&gc_lock);
+ list_add_tail(&gc->list, &gc_list);
+ raw_spin_unlock(&gc_lock);
+
+ /* Init mask cache ? */
+ if (flags & IRQ_GC_INIT_MASK_CACHE)
+ gc->mask_cache = irq_reg_readl(gc->reg_base + ct->regs.mask);
+
+ for (i = gc->irq_base; msk; msk >>= 1, i++) {
+ if (!msk & 0x01)
+ continue;
+
+ if (flags & IRQ_GC_INIT_NESTED_LOCK)
+ irq_set_lockdep_class(i, &irq_nested_lock_class);
+
+ irq_set_chip_and_handler(i, &ct->chip, ct->handler);
+ irq_set_chip_data(i, gc);
+ irq_modify_status(i, clr, set);
+ }
+ gc->irq_cnt = i - gc->irq_base;
+}
+
+/**
+ * irq_setup_alt_chip - Switch to alternative chip
+ * @d: irq_data for this interrupt
+ * @type Flow type to be initialized
+ *
+ * Only to be called from chip->irq_set_type() callbacks.
+ */
+int irq_setup_alt_chip(struct irq_data *d, unsigned int type)
+{
+ struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
+ struct irq_chip_type *ct = gc->chip_types;
+ unsigned int i;
+
+ for (i = 0; i < gc->num_ct; i++, ct++) {
+ if (ct->type & type) {
+ d->chip = &ct->chip;
+ irq_data_to_desc(d)->handle_irq = ct->handler;
+ return 0;
+ }
+ }
+ return -EINVAL;
+}
+
+/**
+ * irq_remove_generic_chip - Remove a chip
+ * @gc: Generic irq chip holding all data
+ * @msk: Bitmask holding the irqs to initialize relative to gc->irq_base
+ * @clr: IRQ_* bits to clear
+ * @set: IRQ_* bits to set
+ *
+ * Remove up to 32 interrupts starting from gc->irq_base.
+ */
+void irq_remove_generic_chip(struct irq_chip_generic *gc, u32 msk,
+ unsigned int clr, unsigned int set)
+{
+ unsigned int i = gc->irq_base;
+
+ raw_spin_lock(&gc_lock);
+ list_del(&gc->list);
+ raw_spin_unlock(&gc_lock);
+
+ for (; msk; msk >>= 1, i++) {
+ if (!msk & 0x01)
+ continue;
+
+ /* Remove handler first. That will mask the irq line */
+ irq_set_handler(i, NULL);
+ irq_set_chip(i, &no_irq_chip);
+ irq_set_chip_data(i, NULL);
+ irq_modify_status(i, clr, set);
+ }
+}
+
+#ifdef CONFIG_PM
+static int irq_gc_suspend(void)
+{
+ struct irq_chip_generic *gc;
+
+ list_for_each_entry(gc, &gc_list, list) {
+ struct irq_chip_type *ct = gc->chip_types;
+
+ if (ct->chip.irq_suspend)
+ ct->chip.irq_suspend(irq_get_irq_data(gc->irq_base));
+ }
+ return 0;
+}
+
+static void irq_gc_resume(void)
+{
+ struct irq_chip_generic *gc;
+
+ list_for_each_entry(gc, &gc_list, list) {
+ struct irq_chip_type *ct = gc->chip_types;
+
+ if (ct->chip.irq_resume)
+ ct->chip.irq_resume(irq_get_irq_data(gc->irq_base));
+ }
+}
+#else
+#define irq_gc_suspend NULL
+#define irq_gc_resume NULL
+#endif
+
+static void irq_gc_shutdown(void)
+{
+ struct irq_chip_generic *gc;
+
+ list_for_each_entry(gc, &gc_list, list) {
+ struct irq_chip_type *ct = gc->chip_types;
+
+ if (ct->chip.irq_pm_shutdown)
+ ct->chip.irq_pm_shutdown(irq_get_irq_data(gc->irq_base));
+ }
+}
+
+static struct syscore_ops irq_gc_syscore_ops = {
+ .suspend = irq_gc_suspend,
+ .resume = irq_gc_resume,
+ .shutdown = irq_gc_shutdown,
+};
+
+static int __init irq_gc_init_ops(void)
+{
+ register_syscore_ops(&irq_gc_syscore_ops);
+ return 0;
+}
+device_initcall(irq_gc_init_ops);
diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c
index 2c039c9b938..886e80347b3 100644
--- a/kernel/irq/irqdesc.c
+++ b/kernel/irq/irqdesc.c
@@ -22,7 +22,7 @@
*/
static struct lock_class_key irq_desc_lock_class;
-#if defined(CONFIG_SMP) && defined(CONFIG_GENERIC_HARDIRQS)
+#if defined(CONFIG_SMP)
static void __init init_irq_default_affinity(void)
{
alloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT);
@@ -290,6 +290,22 @@ static int irq_expand_nr_irqs(unsigned int nr)
#endif /* !CONFIG_SPARSE_IRQ */
+/**
+ * generic_handle_irq - Invoke the handler for a particular irq
+ * @irq: The irq number to handle
+ *
+ */
+int generic_handle_irq(unsigned int irq)
+{
+ struct irq_desc *desc = irq_to_desc(irq);
+
+ if (!desc)
+ return -EINVAL;
+ generic_handle_irq_desc(irq, desc);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(generic_handle_irq);
+
/* Dynamic interrupt handling */
/**
@@ -311,6 +327,7 @@ void irq_free_descs(unsigned int from, unsigned int cnt)
bitmap_clear(allocated_irqs, from, cnt);
mutex_unlock(&sparse_irq_lock);
}
+EXPORT_SYMBOL_GPL(irq_free_descs);
/**
* irq_alloc_descs - allocate and initialize a range of irq descriptors
@@ -351,6 +368,7 @@ err:
mutex_unlock(&sparse_irq_lock);
return ret;
}
+EXPORT_SYMBOL_GPL(irq_alloc_descs);
/**
* irq_reserve_irqs - mark irqs allocated
@@ -430,7 +448,6 @@ unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
*per_cpu_ptr(desc->kstat_irqs, cpu) : 0;
}
-#ifdef CONFIG_GENERIC_HARDIRQS
unsigned int kstat_irqs(unsigned int irq)
{
struct irq_desc *desc = irq_to_desc(irq);
@@ -443,4 +460,3 @@ unsigned int kstat_irqs(unsigned int irq)
sum += *per_cpu_ptr(desc->kstat_irqs, cpu);
return sum;
}
-#endif /* CONFIG_GENERIC_HARDIRQS */
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 07c1611f389..f7ce0021e1c 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -900,7 +900,8 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
*/
new->handler = irq_nested_primary_handler;
} else {
- irq_setup_forced_threading(new);
+ if (irq_settings_can_thread(desc))
+ irq_setup_forced_threading(new);
}
/*
diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c
index dd201bd3510..834899f2500 100644
--- a/kernel/irq/proc.c
+++ b/kernel/irq/proc.c
@@ -419,7 +419,7 @@ int show_interrupts(struct seq_file *p, void *v)
} else {
seq_printf(p, " %8s", "None");
}
-#ifdef CONFIG_GENIRC_IRQ_SHOW_LEVEL
+#ifdef CONFIG_GENERIC_IRQ_SHOW_LEVEL
seq_printf(p, " %-8s", irqd_is_level_type(&desc->irq_data) ? "Level" : "Edge");
#endif
if (desc->name)
diff --git a/kernel/irq/settings.h b/kernel/irq/settings.h
index 0d91730b633..f1667833d44 100644
--- a/kernel/irq/settings.h
+++ b/kernel/irq/settings.h
@@ -8,6 +8,7 @@ enum {
_IRQ_LEVEL = IRQ_LEVEL,
_IRQ_NOPROBE = IRQ_NOPROBE,
_IRQ_NOREQUEST = IRQ_NOREQUEST,
+ _IRQ_NOTHREAD = IRQ_NOTHREAD,
_IRQ_NOAUTOEN = IRQ_NOAUTOEN,
_IRQ_MOVE_PCNTXT = IRQ_MOVE_PCNTXT,
_IRQ_NO_BALANCING = IRQ_NO_BALANCING,
@@ -20,6 +21,7 @@ enum {
#define IRQ_LEVEL GOT_YOU_MORON
#define IRQ_NOPROBE GOT_YOU_MORON
#define IRQ_NOREQUEST GOT_YOU_MORON
+#define IRQ_NOTHREAD GOT_YOU_MORON
#define IRQ_NOAUTOEN GOT_YOU_MORON
#define IRQ_NESTED_THREAD GOT_YOU_MORON
#undef IRQF_MODIFY_MASK
@@ -94,6 +96,21 @@ static inline void irq_settings_set_norequest(struct irq_desc *desc)
desc->status_use_accessors |= _IRQ_NOREQUEST;
}
+static inline bool irq_settings_can_thread(struct irq_desc *desc)
+{
+ return !(desc->status_use_accessors & _IRQ_NOTHREAD);
+}
+
+static inline void irq_settings_clr_nothread(struct irq_desc *desc)
+{
+ desc->status_use_accessors &= ~_IRQ_NOTHREAD;
+}
+
+static inline void irq_settings_set_nothread(struct irq_desc *desc)
+{
+ desc->status_use_accessors |= _IRQ_NOTHREAD;
+}
+
static inline bool irq_settings_can_probe(struct irq_desc *desc)
{
return !(desc->status_use_accessors & _IRQ_NOPROBE);
diff --git a/kernel/jump_label.c b/kernel/jump_label.c
index 3b79bd93833..74d1c099fbd 100644
--- a/kernel/jump_label.c
+++ b/kernel/jump_label.c
@@ -2,43 +2,23 @@
* jump label support
*
* Copyright (C) 2009 Jason Baron <jbaron@redhat.com>
+ * Copyright (C) 2011 Peter Zijlstra <pzijlstr@redhat.com>
*
*/
-#include <linux/jump_label.h>
#include <linux/memory.h>
#include <linux/uaccess.h>
#include <linux/module.h>
#include <linux/list.h>
-#include <linux/jhash.h>
#include <linux/slab.h>
#include <linux/sort.h>
#include <linux/err.h>
+#include <linux/jump_label.h>
#ifdef HAVE_JUMP_LABEL
-#define JUMP_LABEL_HASH_BITS 6
-#define JUMP_LABEL_TABLE_SIZE (1 << JUMP_LABEL_HASH_BITS)
-static struct hlist_head jump_label_table[JUMP_LABEL_TABLE_SIZE];
-
/* mutex to protect coming/going of the the jump_label table */
static DEFINE_MUTEX(jump_label_mutex);
-struct jump_label_entry {
- struct hlist_node hlist;
- struct jump_entry *table;
- int nr_entries;
- /* hang modules off here */
- struct hlist_head modules;
- unsigned long key;
-};
-
-struct jump_label_module_entry {
- struct hlist_node hlist;
- struct jump_entry *table;
- int nr_entries;
- struct module *mod;
-};
-
void jump_label_lock(void)
{
mutex_lock(&jump_label_mutex);
@@ -49,6 +29,11 @@ void jump_label_unlock(void)
mutex_unlock(&jump_label_mutex);
}
+bool jump_label_enabled(struct jump_label_key *key)
+{
+ return !!atomic_read(&key->enabled);
+}
+
static int jump_label_cmp(const void *a, const void *b)
{
const struct jump_entry *jea = a;
@@ -64,7 +49,7 @@ static int jump_label_cmp(const void *a, const void *b)
}
static void
-sort_jump_label_entries(struct jump_entry *start, struct jump_entry *stop)
+jump_label_sort_entries(struct jump_entry *start, struct jump_entry *stop)
{
unsigned long size;
@@ -73,118 +58,25 @@ sort_jump_label_entries(struct jump_entry *start, struct jump_entry *stop)
sort(start, size, sizeof(struct jump_entry), jump_label_cmp, NULL);
}
-static struct jump_label_entry *get_jump_label_entry(jump_label_t key)
-{
- struct hlist_head *head;
- struct hlist_node *node;
- struct jump_label_entry *e;
- u32 hash = jhash((void *)&key, sizeof(jump_label_t), 0);
-
- head = &jump_label_table[hash & (JUMP_LABEL_TABLE_SIZE - 1)];
- hlist_for_each_entry(e, node, head, hlist) {
- if (key == e->key)
- return e;
- }
- return NULL;
-}
+static void jump_label_update(struct jump_label_key *key, int enable);
-static struct jump_label_entry *
-add_jump_label_entry(jump_label_t key, int nr_entries, struct jump_entry *table)
+void jump_label_inc(struct jump_label_key *key)
{
- struct hlist_head *head;
- struct jump_label_entry *e;
- u32 hash;
-
- e = get_jump_label_entry(key);
- if (e)
- return ERR_PTR(-EEXIST);
-
- e = kmalloc(sizeof(struct jump_label_entry), GFP_KERNEL);
- if (!e)
- return ERR_PTR(-ENOMEM);
-
- hash = jhash((void *)&key, sizeof(jump_label_t), 0);
- head = &jump_label_table[hash & (JUMP_LABEL_TABLE_SIZE - 1)];
- e->key = key;
- e->table = table;
- e->nr_entries = nr_entries;
- INIT_HLIST_HEAD(&(e->modules));
- hlist_add_head(&e->hlist, head);
- return e;
-}
+ if (atomic_inc_not_zero(&key->enabled))
+ return;
-static int
-build_jump_label_hashtable(struct jump_entry *start, struct jump_entry *stop)
-{
- struct jump_entry *iter, *iter_begin;
- struct jump_label_entry *entry;
- int count;
-
- sort_jump_label_entries(start, stop);
- iter = start;
- while (iter < stop) {
- entry = get_jump_label_entry(iter->key);
- if (!entry) {
- iter_begin = iter;
- count = 0;
- while ((iter < stop) &&
- (iter->key == iter_begin->key)) {
- iter++;
- count++;
- }
- entry = add_jump_label_entry(iter_begin->key,
- count, iter_begin);
- if (IS_ERR(entry))
- return PTR_ERR(entry);
- } else {
- WARN_ONCE(1, KERN_ERR "build_jump_hashtable: unexpected entry!\n");
- return -1;
- }
- }
- return 0;
+ jump_label_lock();
+ if (atomic_add_return(1, &key->enabled) == 1)
+ jump_label_update(key, JUMP_LABEL_ENABLE);
+ jump_label_unlock();
}
-/***
- * jump_label_update - update jump label text
- * @key - key value associated with a a jump label
- * @type - enum set to JUMP_LABEL_ENABLE or JUMP_LABEL_DISABLE
- *
- * Will enable/disable the jump for jump label @key, depending on the
- * value of @type.
- *
- */
-
-void jump_label_update(unsigned long key, enum jump_label_type type)
+void jump_label_dec(struct jump_label_key *key)
{
- struct jump_entry *iter;
- struct jump_label_entry *entry;
- struct hlist_node *module_node;
- struct jump_label_module_entry *e_module;
- int count;
+ if (!atomic_dec_and_mutex_lock(&key->enabled, &jump_label_mutex))
+ return;
- jump_label_lock();
- entry = get_jump_label_entry((jump_label_t)key);
- if (entry) {
- count = entry->nr_entries;
- iter = entry->table;
- while (count--) {
- if (kernel_text_address(iter->code))
- arch_jump_label_transform(iter, type);
- iter++;
- }
- /* eanble/disable jump labels in modules */
- hlist_for_each_entry(e_module, module_node, &(entry->modules),
- hlist) {
- count = e_module->nr_entries;
- iter = e_module->table;
- while (count--) {
- if (iter->key &&
- kernel_text_address(iter->code))
- arch_jump_label_transform(iter, type);
- iter++;
- }
- }
- }
+ jump_label_update(key, JUMP_LABEL_DISABLE);
jump_label_unlock();
}
@@ -197,77 +89,33 @@ static int addr_conflict(struct jump_entry *entry, void *start, void *end)
return 0;
}
-#ifdef CONFIG_MODULES
-
-static int module_conflict(void *start, void *end)
+static int __jump_label_text_reserved(struct jump_entry *iter_start,
+ struct jump_entry *iter_stop, void *start, void *end)
{
- struct hlist_head *head;
- struct hlist_node *node, *node_next, *module_node, *module_node_next;
- struct jump_label_entry *e;
- struct jump_label_module_entry *e_module;
struct jump_entry *iter;
- int i, count;
- int conflict = 0;
-
- for (i = 0; i < JUMP_LABEL_TABLE_SIZE; i++) {
- head = &jump_label_table[i];
- hlist_for_each_entry_safe(e, node, node_next, head, hlist) {
- hlist_for_each_entry_safe(e_module, module_node,
- module_node_next,
- &(e->modules), hlist) {
- count = e_module->nr_entries;
- iter = e_module->table;
- while (count--) {
- if (addr_conflict(iter, start, end)) {
- conflict = 1;
- goto out;
- }
- iter++;
- }
- }
- }
- }
-out:
- return conflict;
-}
-
-#endif
-
-/***
- * jump_label_text_reserved - check if addr range is reserved
- * @start: start text addr
- * @end: end text addr
- *
- * checks if the text addr located between @start and @end
- * overlaps with any of the jump label patch addresses. Code
- * that wants to modify kernel text should first verify that
- * it does not overlap with any of the jump label addresses.
- * Caller must hold jump_label_mutex.
- *
- * returns 1 if there is an overlap, 0 otherwise
- */
-int jump_label_text_reserved(void *start, void *end)
-{
- struct jump_entry *iter;
- struct jump_entry *iter_start = __start___jump_table;
- struct jump_entry *iter_stop = __start___jump_table;
- int conflict = 0;
iter = iter_start;
while (iter < iter_stop) {
- if (addr_conflict(iter, start, end)) {
- conflict = 1;
- goto out;
- }
+ if (addr_conflict(iter, start, end))
+ return 1;
iter++;
}
- /* now check modules */
-#ifdef CONFIG_MODULES
- conflict = module_conflict(start, end);
-#endif
-out:
- return conflict;
+ return 0;
+}
+
+static void __jump_label_update(struct jump_label_key *key,
+ struct jump_entry *entry, int enable)
+{
+ for (; entry->key == (jump_label_t)(unsigned long)key; entry++) {
+ /*
+ * entry->code set to 0 invalidates module init text sections
+ * kernel_text_address() verifies we are not in core kernel
+ * init code, see jump_label_invalidate_module_init().
+ */
+ if (entry->code && kernel_text_address(entry->code))
+ arch_jump_label_transform(entry, enable);
+ }
}
/*
@@ -277,142 +125,173 @@ void __weak arch_jump_label_text_poke_early(jump_label_t addr)
{
}
-static __init int init_jump_label(void)
+static __init int jump_label_init(void)
{
- int ret;
struct jump_entry *iter_start = __start___jump_table;
struct jump_entry *iter_stop = __stop___jump_table;
+ struct jump_label_key *key = NULL;
struct jump_entry *iter;
jump_label_lock();
- ret = build_jump_label_hashtable(__start___jump_table,
- __stop___jump_table);
- iter = iter_start;
- while (iter < iter_stop) {
+ jump_label_sort_entries(iter_start, iter_stop);
+
+ for (iter = iter_start; iter < iter_stop; iter++) {
arch_jump_label_text_poke_early(iter->code);
- iter++;
+ if (iter->key == (jump_label_t)(unsigned long)key)
+ continue;
+
+ key = (struct jump_label_key *)(unsigned long)iter->key;
+ atomic_set(&key->enabled, 0);
+ key->entries = iter;
+#ifdef CONFIG_MODULES
+ key->next = NULL;
+#endif
}
jump_label_unlock();
- return ret;
+
+ return 0;
}
-early_initcall(init_jump_label);
+early_initcall(jump_label_init);
#ifdef CONFIG_MODULES
-static struct jump_label_module_entry *
-add_jump_label_module_entry(struct jump_label_entry *entry,
- struct jump_entry *iter_begin,
- int count, struct module *mod)
+struct jump_label_mod {
+ struct jump_label_mod *next;
+ struct jump_entry *entries;
+ struct module *mod;
+};
+
+static int __jump_label_mod_text_reserved(void *start, void *end)
+{
+ struct module *mod;
+
+ mod = __module_text_address((unsigned long)start);
+ if (!mod)
+ return 0;
+
+ WARN_ON_ONCE(__module_text_address((unsigned long)end) != mod);
+
+ return __jump_label_text_reserved(mod->jump_entries,
+ mod->jump_entries + mod->num_jump_entries,
+ start, end);
+}
+
+static void __jump_label_mod_update(struct jump_label_key *key, int enable)
+{
+ struct jump_label_mod *mod = key->next;
+
+ while (mod) {
+ __jump_label_update(key, mod->entries, enable);
+ mod = mod->next;
+ }
+}
+
+/***
+ * apply_jump_label_nops - patch module jump labels with arch_get_jump_label_nop()
+ * @mod: module to patch
+ *
+ * Allow for run-time selection of the optimal nops. Before the module
+ * loads patch these with arch_get_jump_label_nop(), which is specified by
+ * the arch specific jump label code.
+ */
+void jump_label_apply_nops(struct module *mod)
{
- struct jump_label_module_entry *e;
-
- e = kmalloc(sizeof(struct jump_label_module_entry), GFP_KERNEL);
- if (!e)
- return ERR_PTR(-ENOMEM);
- e->mod = mod;
- e->nr_entries = count;
- e->table = iter_begin;
- hlist_add_head(&e->hlist, &entry->modules);
- return e;
+ struct jump_entry *iter_start = mod->jump_entries;
+ struct jump_entry *iter_stop = iter_start + mod->num_jump_entries;
+ struct jump_entry *iter;
+
+ /* if the module doesn't have jump label entries, just return */
+ if (iter_start == iter_stop)
+ return;
+
+ for (iter = iter_start; iter < iter_stop; iter++)
+ arch_jump_label_text_poke_early(iter->code);
}
-static int add_jump_label_module(struct module *mod)
+static int jump_label_add_module(struct module *mod)
{
- struct jump_entry *iter, *iter_begin;
- struct jump_label_entry *entry;
- struct jump_label_module_entry *module_entry;
- int count;
+ struct jump_entry *iter_start = mod->jump_entries;
+ struct jump_entry *iter_stop = iter_start + mod->num_jump_entries;
+ struct jump_entry *iter;
+ struct jump_label_key *key = NULL;
+ struct jump_label_mod *jlm;
/* if the module doesn't have jump label entries, just return */
- if (!mod->num_jump_entries)
+ if (iter_start == iter_stop)
return 0;
- sort_jump_label_entries(mod->jump_entries,
- mod->jump_entries + mod->num_jump_entries);
- iter = mod->jump_entries;
- while (iter < mod->jump_entries + mod->num_jump_entries) {
- entry = get_jump_label_entry(iter->key);
- iter_begin = iter;
- count = 0;
- while ((iter < mod->jump_entries + mod->num_jump_entries) &&
- (iter->key == iter_begin->key)) {
- iter++;
- count++;
- }
- if (!entry) {
- entry = add_jump_label_entry(iter_begin->key, 0, NULL);
- if (IS_ERR(entry))
- return PTR_ERR(entry);
+ jump_label_sort_entries(iter_start, iter_stop);
+
+ for (iter = iter_start; iter < iter_stop; iter++) {
+ if (iter->key == (jump_label_t)(unsigned long)key)
+ continue;
+
+ key = (struct jump_label_key *)(unsigned long)iter->key;
+
+ if (__module_address(iter->key) == mod) {
+ atomic_set(&key->enabled, 0);
+ key->entries = iter;
+ key->next = NULL;
+ continue;
}
- module_entry = add_jump_label_module_entry(entry, iter_begin,
- count, mod);
- if (IS_ERR(module_entry))
- return PTR_ERR(module_entry);
+
+ jlm = kzalloc(sizeof(struct jump_label_mod), GFP_KERNEL);
+ if (!jlm)
+ return -ENOMEM;
+
+ jlm->mod = mod;
+ jlm->entries = iter;
+ jlm->next = key->next;
+ key->next = jlm;
+
+ if (jump_label_enabled(key))
+ __jump_label_update(key, iter, JUMP_LABEL_ENABLE);
}
+
return 0;
}
-static void remove_jump_label_module(struct module *mod)
+static void jump_label_del_module(struct module *mod)
{
- struct hlist_head *head;
- struct hlist_node *node, *node_next, *module_node, *module_node_next;
- struct jump_label_entry *e;
- struct jump_label_module_entry *e_module;
- int i;
+ struct jump_entry *iter_start = mod->jump_entries;
+ struct jump_entry *iter_stop = iter_start + mod->num_jump_entries;
+ struct jump_entry *iter;
+ struct jump_label_key *key = NULL;
+ struct jump_label_mod *jlm, **prev;
- /* if the module doesn't have jump label entries, just return */
- if (!mod->num_jump_entries)
- return;
+ for (iter = iter_start; iter < iter_stop; iter++) {
+ if (iter->key == (jump_label_t)(unsigned long)key)
+ continue;
+
+ key = (struct jump_label_key *)(unsigned long)iter->key;
+
+ if (__module_address(iter->key) == mod)
+ continue;
+
+ prev = &key->next;
+ jlm = key->next;
- for (i = 0; i < JUMP_LABEL_TABLE_SIZE; i++) {
- head = &jump_label_table[i];
- hlist_for_each_entry_safe(e, node, node_next, head, hlist) {
- hlist_for_each_entry_safe(e_module, module_node,
- module_node_next,
- &(e->modules), hlist) {
- if (e_module->mod == mod) {
- hlist_del(&e_module->hlist);
- kfree(e_module);
- }
- }
- if (hlist_empty(&e->modules) && (e->nr_entries == 0)) {
- hlist_del(&e->hlist);
- kfree(e);
- }
+ while (jlm && jlm->mod != mod) {
+ prev = &jlm->next;
+ jlm = jlm->next;
+ }
+
+ if (jlm) {
+ *prev = jlm->next;
+ kfree(jlm);
}
}
}
-static void remove_jump_label_module_init(struct module *mod)
+static void jump_label_invalidate_module_init(struct module *mod)
{
- struct hlist_head *head;
- struct hlist_node *node, *node_next, *module_node, *module_node_next;
- struct jump_label_entry *e;
- struct jump_label_module_entry *e_module;
+ struct jump_entry *iter_start = mod->jump_entries;
+ struct jump_entry *iter_stop = iter_start + mod->num_jump_entries;
struct jump_entry *iter;
- int i, count;
-
- /* if the module doesn't have jump label entries, just return */
- if (!mod->num_jump_entries)
- return;
- for (i = 0; i < JUMP_LABEL_TABLE_SIZE; i++) {
- head = &jump_label_table[i];
- hlist_for_each_entry_safe(e, node, node_next, head, hlist) {
- hlist_for_each_entry_safe(e_module, module_node,
- module_node_next,
- &(e->modules), hlist) {
- if (e_module->mod != mod)
- continue;
- count = e_module->nr_entries;
- iter = e_module->table;
- while (count--) {
- if (within_module_init(iter->code, mod))
- iter->key = 0;
- iter++;
- }
- }
- }
+ for (iter = iter_start; iter < iter_stop; iter++) {
+ if (within_module_init(iter->code, mod))
+ iter->code = 0;
}
}
@@ -426,59 +305,77 @@ jump_label_module_notify(struct notifier_block *self, unsigned long val,
switch (val) {
case MODULE_STATE_COMING:
jump_label_lock();
- ret = add_jump_label_module(mod);
+ ret = jump_label_add_module(mod);
if (ret)
- remove_jump_label_module(mod);
+ jump_label_del_module(mod);
jump_label_unlock();
break;
case MODULE_STATE_GOING:
jump_label_lock();
- remove_jump_label_module(mod);
+ jump_label_del_module(mod);
jump_label_unlock();
break;
case MODULE_STATE_LIVE:
jump_label_lock();
- remove_jump_label_module_init(mod);
+ jump_label_invalidate_module_init(mod);
jump_label_unlock();
break;
}
- return ret;
-}
-/***
- * apply_jump_label_nops - patch module jump labels with arch_get_jump_label_nop()
- * @mod: module to patch
- *
- * Allow for run-time selection of the optimal nops. Before the module
- * loads patch these with arch_get_jump_label_nop(), which is specified by
- * the arch specific jump label code.
- */
-void jump_label_apply_nops(struct module *mod)
-{
- struct jump_entry *iter;
-
- /* if the module doesn't have jump label entries, just return */
- if (!mod->num_jump_entries)
- return;
-
- iter = mod->jump_entries;
- while (iter < mod->jump_entries + mod->num_jump_entries) {
- arch_jump_label_text_poke_early(iter->code);
- iter++;
- }
+ return notifier_from_errno(ret);
}
struct notifier_block jump_label_module_nb = {
.notifier_call = jump_label_module_notify,
- .priority = 0,
+ .priority = 1, /* higher than tracepoints */
};
-static __init int init_jump_label_module(void)
+static __init int jump_label_init_module(void)
{
return register_module_notifier(&jump_label_module_nb);
}
-early_initcall(init_jump_label_module);
+early_initcall(jump_label_init_module);
#endif /* CONFIG_MODULES */
+/***
+ * jump_label_text_reserved - check if addr range is reserved
+ * @start: start text addr
+ * @end: end text addr
+ *
+ * checks if the text addr located between @start and @end
+ * overlaps with any of the jump label patch addresses. Code
+ * that wants to modify kernel text should first verify that
+ * it does not overlap with any of the jump label addresses.
+ * Caller must hold jump_label_mutex.
+ *
+ * returns 1 if there is an overlap, 0 otherwise
+ */
+int jump_label_text_reserved(void *start, void *end)
+{
+ int ret = __jump_label_text_reserved(__start___jump_table,
+ __stop___jump_table, start, end);
+
+ if (ret)
+ return ret;
+
+#ifdef CONFIG_MODULES
+ ret = __jump_label_mod_text_reserved(start, end);
+#endif
+ return ret;
+}
+
+static void jump_label_update(struct jump_label_key *key, int enable)
+{
+ struct jump_entry *entry = key->entries;
+
+ /* if there are no users, entry can be NULL */
+ if (entry)
+ __jump_label_update(key, entry, enable);
+
+#ifdef CONFIG_MODULES
+ __jump_label_mod_update(key, enable);
+#endif
+}
+
#endif
diff --git a/kernel/kexec.c b/kernel/kexec.c
index 87b77de03dd..8d814cbc810 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -1531,13 +1531,7 @@ int kernel_kexec(void)
if (error)
goto Enable_cpus;
local_irq_disable();
- /* Suspend system devices */
- error = sysdev_suspend(PMSG_FREEZE);
- if (!error) {
- error = syscore_suspend();
- if (error)
- sysdev_resume();
- }
+ error = syscore_suspend();
if (error)
goto Enable_irqs;
} else
@@ -1553,7 +1547,6 @@ int kernel_kexec(void)
#ifdef CONFIG_KEXEC_JUMP
if (kexec_image->preserve_context) {
syscore_resume();
- sysdev_resume();
Enable_irqs:
local_irq_enable();
Enable_cpus:
diff --git a/kernel/kmod.c b/kernel/kmod.c
index 9cd0591c96a..5ae0ff38425 100644
--- a/kernel/kmod.c
+++ b/kernel/kmod.c
@@ -245,7 +245,6 @@ static void __call_usermodehelper(struct work_struct *work)
}
}
-#ifdef CONFIG_PM_SLEEP
/*
* If set, call_usermodehelper_exec() will exit immediately returning -EBUSY
* (used for preventing user land processes from being created after the user
@@ -301,6 +300,15 @@ void usermodehelper_enable(void)
usermodehelper_disabled = 0;
}
+/**
+ * usermodehelper_is_disabled - check if new helpers are allowed to be started
+ */
+bool usermodehelper_is_disabled(void)
+{
+ return usermodehelper_disabled;
+}
+EXPORT_SYMBOL_GPL(usermodehelper_is_disabled);
+
static void helper_lock(void)
{
atomic_inc(&running_helpers);
@@ -312,12 +320,6 @@ static void helper_unlock(void)
if (atomic_dec_and_test(&running_helpers))
wake_up(&running_helpers_waitq);
}
-#else /* CONFIG_PM_SLEEP */
-#define usermodehelper_disabled 0
-
-static inline void helper_lock(void) {}
-static inline void helper_unlock(void) {}
-#endif /* CONFIG_PM_SLEEP */
/**
* call_usermodehelper_setup - prepare to call a usermode helper
diff --git a/kernel/ksysfs.c b/kernel/ksysfs.c
index 0b624e79180..3b053c04dd8 100644
--- a/kernel/ksysfs.c
+++ b/kernel/ksysfs.c
@@ -16,6 +16,7 @@
#include <linux/kexec.h>
#include <linux/profile.h>
#include <linux/sched.h>
+#include <linux/capability.h>
#define KERNEL_ATTR_RO(_name) \
static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
@@ -131,6 +132,14 @@ KERNEL_ATTR_RO(vmcoreinfo);
#endif /* CONFIG_KEXEC */
+/* whether file capabilities are enabled */
+static ssize_t fscaps_show(struct kobject *kobj,
+ struct kobj_attribute *attr, char *buf)
+{
+ return sprintf(buf, "%d\n", file_caps_enabled);
+}
+KERNEL_ATTR_RO(fscaps);
+
/*
* Make /sys/kernel/notes give the raw contents of our kernel .notes section.
*/
@@ -158,6 +167,7 @@ struct kobject *kernel_kobj;
EXPORT_SYMBOL_GPL(kernel_kobj);
static struct attribute * kernel_attrs[] = {
+ &fscaps_attr.attr,
#if defined(CONFIG_HOTPLUG)
&uevent_seqnum_attr.attr,
&uevent_helper_attr.attr,
diff --git a/kernel/lockdep.c b/kernel/lockdep.c
index 53a68956f13..63437d065ac 100644
--- a/kernel/lockdep.c
+++ b/kernel/lockdep.c
@@ -490,6 +490,18 @@ void get_usage_chars(struct lock_class *class, char usage[LOCK_USAGE_CHARS])
usage[i] = '\0';
}
+static int __print_lock_name(struct lock_class *class)
+{
+ char str[KSYM_NAME_LEN];
+ const char *name;
+
+ name = class->name;
+ if (!name)
+ name = __get_key_name(class->key, str);
+
+ return printk("%s", name);
+}
+
static void print_lock_name(struct lock_class *class)
{
char str[KSYM_NAME_LEN], usage[LOCK_USAGE_CHARS];
@@ -1053,6 +1065,56 @@ print_circular_bug_entry(struct lock_list *target, int depth)
return 0;
}
+static void
+print_circular_lock_scenario(struct held_lock *src,
+ struct held_lock *tgt,
+ struct lock_list *prt)
+{
+ struct lock_class *source = hlock_class(src);
+ struct lock_class *target = hlock_class(tgt);
+ struct lock_class *parent = prt->class;
+
+ /*
+ * A direct locking problem where unsafe_class lock is taken
+ * directly by safe_class lock, then all we need to show
+ * is the deadlock scenario, as it is obvious that the
+ * unsafe lock is taken under the safe lock.
+ *
+ * But if there is a chain instead, where the safe lock takes
+ * an intermediate lock (middle_class) where this lock is
+ * not the same as the safe lock, then the lock chain is
+ * used to describe the problem. Otherwise we would need
+ * to show a different CPU case for each link in the chain
+ * from the safe_class lock to the unsafe_class lock.
+ */
+ if (parent != source) {
+ printk("Chain exists of:\n ");
+ __print_lock_name(source);
+ printk(" --> ");
+ __print_lock_name(parent);
+ printk(" --> ");
+ __print_lock_name(target);
+ printk("\n\n");
+ }
+
+ printk(" Possible unsafe locking scenario:\n\n");
+ printk(" CPU0 CPU1\n");
+ printk(" ---- ----\n");
+ printk(" lock(");
+ __print_lock_name(target);
+ printk(");\n");
+ printk(" lock(");
+ __print_lock_name(parent);
+ printk(");\n");
+ printk(" lock(");
+ __print_lock_name(target);
+ printk(");\n");
+ printk(" lock(");
+ __print_lock_name(source);
+ printk(");\n");
+ printk("\n *** DEADLOCK ***\n\n");
+}
+
/*
* When a circular dependency is detected, print the
* header first:
@@ -1096,6 +1158,7 @@ static noinline int print_circular_bug(struct lock_list *this,
{
struct task_struct *curr = current;
struct lock_list *parent;
+ struct lock_list *first_parent;
int depth;
if (!debug_locks_off_graph_unlock() || debug_locks_silent)
@@ -1109,6 +1172,7 @@ static noinline int print_circular_bug(struct lock_list *this,
print_circular_bug_header(target, depth, check_src, check_tgt);
parent = get_lock_parent(target);
+ first_parent = parent;
while (parent) {
print_circular_bug_entry(parent, --depth);
@@ -1116,6 +1180,9 @@ static noinline int print_circular_bug(struct lock_list *this,
}
printk("\nother info that might help us debug this:\n\n");
+ print_circular_lock_scenario(check_src, check_tgt,
+ first_parent);
+
lockdep_print_held_locks(curr);
printk("\nstack backtrace:\n");
@@ -1314,7 +1381,7 @@ print_shortest_lock_dependencies(struct lock_list *leaf,
printk("\n");
if (depth == 0 && (entry != root)) {
- printk("lockdep:%s bad BFS generated tree\n", __func__);
+ printk("lockdep:%s bad path found in chain graph\n", __func__);
break;
}
@@ -1325,6 +1392,62 @@ print_shortest_lock_dependencies(struct lock_list *leaf,
return;
}
+static void
+print_irq_lock_scenario(struct lock_list *safe_entry,
+ struct lock_list *unsafe_entry,
+ struct lock_class *prev_class,
+ struct lock_class *next_class)
+{
+ struct lock_class *safe_class = safe_entry->class;
+ struct lock_class *unsafe_class = unsafe_entry->class;
+ struct lock_class *middle_class = prev_class;
+
+ if (middle_class == safe_class)
+ middle_class = next_class;
+
+ /*
+ * A direct locking problem where unsafe_class lock is taken
+ * directly by safe_class lock, then all we need to show
+ * is the deadlock scenario, as it is obvious that the
+ * unsafe lock is taken under the safe lock.
+ *
+ * But if there is a chain instead, where the safe lock takes
+ * an intermediate lock (middle_class) where this lock is
+ * not the same as the safe lock, then the lock chain is
+ * used to describe the problem. Otherwise we would need
+ * to show a different CPU case for each link in the chain
+ * from the safe_class lock to the unsafe_class lock.
+ */
+ if (middle_class != unsafe_class) {
+ printk("Chain exists of:\n ");
+ __print_lock_name(safe_class);
+ printk(" --> ");
+ __print_lock_name(middle_class);
+ printk(" --> ");
+ __print_lock_name(unsafe_class);
+ printk("\n\n");
+ }
+
+ printk(" Possible interrupt unsafe locking scenario:\n\n");
+ printk(" CPU0 CPU1\n");
+ printk(" ---- ----\n");
+ printk(" lock(");
+ __print_lock_name(unsafe_class);
+ printk(");\n");
+ printk(" local_irq_disable();\n");
+ printk(" lock(");
+ __print_lock_name(safe_class);
+ printk(");\n");
+ printk(" lock(");
+ __print_lock_name(middle_class);
+ printk(");\n");
+ printk(" <Interrupt>\n");
+ printk(" lock(");
+ __print_lock_name(safe_class);
+ printk(");\n");
+ printk("\n *** DEADLOCK ***\n\n");
+}
+
static int
print_bad_irq_dependency(struct task_struct *curr,
struct lock_list *prev_root,
@@ -1376,6 +1499,9 @@ print_bad_irq_dependency(struct task_struct *curr,
print_stack_trace(forwards_entry->class->usage_traces + bit2, 1);
printk("\nother info that might help us debug this:\n\n");
+ print_irq_lock_scenario(backwards_entry, forwards_entry,
+ hlock_class(prev), hlock_class(next));
+
lockdep_print_held_locks(curr);
printk("\nthe dependencies between %s-irq-safe lock", irqclass);
@@ -1539,6 +1665,26 @@ static inline void inc_chains(void)
#endif
+static void
+print_deadlock_scenario(struct held_lock *nxt,
+ struct held_lock *prv)
+{
+ struct lock_class *next = hlock_class(nxt);
+ struct lock_class *prev = hlock_class(prv);
+
+ printk(" Possible unsafe locking scenario:\n\n");
+ printk(" CPU0\n");
+ printk(" ----\n");
+ printk(" lock(");
+ __print_lock_name(prev);
+ printk(");\n");
+ printk(" lock(");
+ __print_lock_name(next);
+ printk(");\n");
+ printk("\n *** DEADLOCK ***\n\n");
+ printk(" May be due to missing lock nesting notation\n\n");
+}
+
static int
print_deadlock_bug(struct task_struct *curr, struct held_lock *prev,
struct held_lock *next)
@@ -1557,6 +1703,7 @@ print_deadlock_bug(struct task_struct *curr, struct held_lock *prev,
print_lock(prev);
printk("\nother info that might help us debug this:\n");
+ print_deadlock_scenario(next, prev);
lockdep_print_held_locks(curr);
printk("\nstack backtrace:\n");
@@ -1826,7 +1973,7 @@ static inline int lookup_chain_cache(struct task_struct *curr,
struct list_head *hash_head = chainhashentry(chain_key);
struct lock_chain *chain;
struct held_lock *hlock_curr, *hlock_next;
- int i, j, n, cn;
+ int i, j;
if (DEBUG_LOCKS_WARN_ON(!irqs_disabled()))
return 0;
@@ -1886,15 +2033,9 @@ cache_hit:
}
i++;
chain->depth = curr->lockdep_depth + 1 - i;
- cn = nr_chain_hlocks;
- while (cn + chain->depth <= MAX_LOCKDEP_CHAIN_HLOCKS) {
- n = cmpxchg(&nr_chain_hlocks, cn, cn + chain->depth);
- if (n == cn)
- break;
- cn = n;
- }
- if (likely(cn + chain->depth <= MAX_LOCKDEP_CHAIN_HLOCKS)) {
- chain->base = cn;
+ if (likely(nr_chain_hlocks + chain->depth <= MAX_LOCKDEP_CHAIN_HLOCKS)) {
+ chain->base = nr_chain_hlocks;
+ nr_chain_hlocks += chain->depth;
for (j = 0; j < chain->depth - 1; j++, i++) {
int lock_id = curr->held_locks[i].class_idx - 1;
chain_hlocks[chain->base + j] = lock_id;
@@ -2011,6 +2152,24 @@ static void check_chain_key(struct task_struct *curr)
#endif
}
+static void
+print_usage_bug_scenario(struct held_lock *lock)
+{
+ struct lock_class *class = hlock_class(lock);
+
+ printk(" Possible unsafe locking scenario:\n\n");
+ printk(" CPU0\n");
+ printk(" ----\n");
+ printk(" lock(");
+ __print_lock_name(class);
+ printk(");\n");
+ printk(" <Interrupt>\n");
+ printk(" lock(");
+ __print_lock_name(class);
+ printk(");\n");
+ printk("\n *** DEADLOCK ***\n\n");
+}
+
static int
print_usage_bug(struct task_struct *curr, struct held_lock *this,
enum lock_usage_bit prev_bit, enum lock_usage_bit new_bit)
@@ -2039,6 +2198,8 @@ print_usage_bug(struct task_struct *curr, struct held_lock *this,
print_irqtrace_events(curr);
printk("\nother info that might help us debug this:\n");
+ print_usage_bug_scenario(this);
+
lockdep_print_held_locks(curr);
printk("\nstack backtrace:\n");
@@ -2073,6 +2234,10 @@ print_irq_inversion_bug(struct task_struct *curr,
struct held_lock *this, int forwards,
const char *irqclass)
{
+ struct lock_list *entry = other;
+ struct lock_list *middle = NULL;
+ int depth;
+
if (!debug_locks_off_graph_unlock() || debug_locks_silent)
return 0;
@@ -2091,6 +2256,25 @@ print_irq_inversion_bug(struct task_struct *curr,
printk("\n\nand interrupts could create inverse lock ordering between them.\n\n");
printk("\nother info that might help us debug this:\n");
+
+ /* Find a middle lock (if one exists) */
+ depth = get_lock_depth(other);
+ do {
+ if (depth == 0 && (entry != root)) {
+ printk("lockdep:%s bad path found in chain graph\n", __func__);
+ break;
+ }
+ middle = entry;
+ entry = get_lock_parent(entry);
+ depth--;
+ } while (entry && entry != root && (depth >= 0));
+ if (forwards)
+ print_irq_lock_scenario(root, other,
+ middle ? middle->class : root->class, other->class);
+ else
+ print_irq_lock_scenario(other, root,
+ middle ? middle->class : other->class, root->class);
+
lockdep_print_held_locks(curr);
printk("\nthe shortest dependencies between 2nd lock and 1st lock:\n");
diff --git a/kernel/module.c b/kernel/module.c
index d5938a5c19c..22879725678 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -57,6 +57,7 @@
#include <linux/kmemleak.h>
#include <linux/jump_label.h>
#include <linux/pfn.h>
+#include <linux/bsearch.h>
#define CREATE_TRACE_POINTS
#include <trace/events/module.h>
@@ -240,23 +241,24 @@ static bool each_symbol_in_section(const struct symsearch *arr,
struct module *owner,
bool (*fn)(const struct symsearch *syms,
struct module *owner,
- unsigned int symnum, void *data),
+ void *data),
void *data)
{
- unsigned int i, j;
+ unsigned int j;
for (j = 0; j < arrsize; j++) {
- for (i = 0; i < arr[j].stop - arr[j].start; i++)
- if (fn(&arr[j], owner, i, data))
- return true;
+ if (fn(&arr[j], owner, data))
+ return true;
}
return false;
}
/* Returns true as soon as fn returns true, otherwise false. */
-bool each_symbol(bool (*fn)(const struct symsearch *arr, struct module *owner,
- unsigned int symnum, void *data), void *data)
+bool each_symbol_section(bool (*fn)(const struct symsearch *arr,
+ struct module *owner,
+ void *data),
+ void *data)
{
struct module *mod;
static const struct symsearch arr[] = {
@@ -309,7 +311,7 @@ bool each_symbol(bool (*fn)(const struct symsearch *arr, struct module *owner,
}
return false;
}
-EXPORT_SYMBOL_GPL(each_symbol);
+EXPORT_SYMBOL_GPL(each_symbol_section);
struct find_symbol_arg {
/* Input */
@@ -323,15 +325,12 @@ struct find_symbol_arg {
const struct kernel_symbol *sym;
};
-static bool find_symbol_in_section(const struct symsearch *syms,
- struct module *owner,
- unsigned int symnum, void *data)
+static bool check_symbol(const struct symsearch *syms,
+ struct module *owner,
+ unsigned int symnum, void *data)
{
struct find_symbol_arg *fsa = data;
- if (strcmp(syms->start[symnum].name, fsa->name) != 0)
- return false;
-
if (!fsa->gplok) {
if (syms->licence == GPL_ONLY)
return false;
@@ -365,6 +364,30 @@ static bool find_symbol_in_section(const struct symsearch *syms,
return true;
}
+static int cmp_name(const void *va, const void *vb)
+{
+ const char *a;
+ const struct kernel_symbol *b;
+ a = va; b = vb;
+ return strcmp(a, b->name);
+}
+
+static bool find_symbol_in_section(const struct symsearch *syms,
+ struct module *owner,
+ void *data)
+{
+ struct find_symbol_arg *fsa = data;
+ struct kernel_symbol *sym;
+
+ sym = bsearch(fsa->name, syms->start, syms->stop - syms->start,
+ sizeof(struct kernel_symbol), cmp_name);
+
+ if (sym != NULL && check_symbol(syms, owner, sym - syms->start, data))
+ return true;
+
+ return false;
+}
+
/* Find a symbol and return it, along with, (optional) crc and
* (optional) module which owns it. Needs preempt disabled or module_mutex. */
const struct kernel_symbol *find_symbol(const char *name,
@@ -379,7 +402,7 @@ const struct kernel_symbol *find_symbol(const char *name,
fsa.gplok = gplok;
fsa.warn = warn;
- if (each_symbol(find_symbol_in_section, &fsa)) {
+ if (each_symbol_section(find_symbol_in_section, &fsa)) {
if (owner)
*owner = fsa.owner;
if (crc)
@@ -1607,27 +1630,28 @@ static void set_section_ro_nx(void *base,
}
}
-/* Setting memory back to RW+NX before releasing it */
-void unset_section_ro_nx(struct module *mod, void *module_region)
+static void unset_module_core_ro_nx(struct module *mod)
{
- unsigned long total_pages;
-
- if (mod->module_core == module_region) {
- /* Set core as NX+RW */
- total_pages = MOD_NUMBER_OF_PAGES(mod->module_core, mod->core_size);
- set_memory_nx((unsigned long)mod->module_core, total_pages);
- set_memory_rw((unsigned long)mod->module_core, total_pages);
+ set_page_attributes(mod->module_core + mod->core_text_size,
+ mod->module_core + mod->core_size,
+ set_memory_x);
+ set_page_attributes(mod->module_core,
+ mod->module_core + mod->core_ro_size,
+ set_memory_rw);
+}
- } else if (mod->module_init == module_region) {
- /* Set init as NX+RW */
- total_pages = MOD_NUMBER_OF_PAGES(mod->module_init, mod->init_size);
- set_memory_nx((unsigned long)mod->module_init, total_pages);
- set_memory_rw((unsigned long)mod->module_init, total_pages);
- }
+static void unset_module_init_ro_nx(struct module *mod)
+{
+ set_page_attributes(mod->module_init + mod->init_text_size,
+ mod->module_init + mod->init_size,
+ set_memory_x);
+ set_page_attributes(mod->module_init,
+ mod->module_init + mod->init_ro_size,
+ set_memory_rw);
}
/* Iterate through all modules and set each module's text as RW */
-void set_all_modules_text_rw()
+void set_all_modules_text_rw(void)
{
struct module *mod;
@@ -1648,7 +1672,7 @@ void set_all_modules_text_rw()
}
/* Iterate through all modules and set each module's text as RO */
-void set_all_modules_text_ro()
+void set_all_modules_text_ro(void)
{
struct module *mod;
@@ -1669,7 +1693,8 @@ void set_all_modules_text_ro()
}
#else
static inline void set_section_ro_nx(void *base, unsigned long text_size, unsigned long ro_size, unsigned long total_size) { }
-static inline void unset_section_ro_nx(struct module *mod, void *module_region) { }
+static void unset_module_core_ro_nx(struct module *mod) { }
+static void unset_module_init_ro_nx(struct module *mod) { }
#endif
/* Free a module, remove from lists, etc. */
@@ -1696,7 +1721,7 @@ static void free_module(struct module *mod)
destroy_params(mod->kp, mod->num_kp);
/* This may be NULL, but that's OK */
- unset_section_ro_nx(mod, mod->module_init);
+ unset_module_init_ro_nx(mod);
module_free(mod, mod->module_init);
kfree(mod->args);
percpu_modfree(mod);
@@ -1705,7 +1730,7 @@ static void free_module(struct module *mod)
lockdep_free_key_range(mod->module_core, mod->core_size);
/* Finally, free the core (containing the module structure) */
- unset_section_ro_nx(mod, mod->module_core);
+ unset_module_core_ro_nx(mod);
module_free(mod, mod->module_core);
#ifdef CONFIG_MPU
@@ -2030,11 +2055,8 @@ static const struct kernel_symbol *lookup_symbol(const char *name,
const struct kernel_symbol *start,
const struct kernel_symbol *stop)
{
- const struct kernel_symbol *ks = start;
- for (; ks < stop; ks++)
- if (strcmp(ks->name, name) == 0)
- return ks;
- return NULL;
+ return bsearch(name, start, stop - start,
+ sizeof(struct kernel_symbol), cmp_name);
}
static int is_exported(const char *name, unsigned long value,
@@ -2931,10 +2953,11 @@ SYSCALL_DEFINE3(init_module, void __user *, umod,
mod->symtab = mod->core_symtab;
mod->strtab = mod->core_strtab;
#endif
- unset_section_ro_nx(mod, mod->module_init);
+ unset_module_init_ro_nx(mod);
module_free(mod, mod->module_init);
mod->module_init = NULL;
mod->init_size = 0;
+ mod->init_ro_size = 0;
mod->init_text_size = 0;
mutex_unlock(&module_mutex);
diff --git a/kernel/mutex-debug.c b/kernel/mutex-debug.c
index ec815a960b5..73da83aff41 100644
--- a/kernel/mutex-debug.c
+++ b/kernel/mutex-debug.c
@@ -75,7 +75,7 @@ void debug_mutex_unlock(struct mutex *lock)
return;
DEBUG_LOCKS_WARN_ON(lock->magic != lock);
- DEBUG_LOCKS_WARN_ON(lock->owner != current_thread_info());
+ DEBUG_LOCKS_WARN_ON(lock->owner != current);
DEBUG_LOCKS_WARN_ON(!lock->wait_list.prev && !lock->wait_list.next);
mutex_clear_owner(lock);
}
diff --git a/kernel/mutex-debug.h b/kernel/mutex-debug.h
index 57d527a16f9..0799fd3e4cf 100644
--- a/kernel/mutex-debug.h
+++ b/kernel/mutex-debug.h
@@ -29,7 +29,7 @@ extern void debug_mutex_init(struct mutex *lock, const char *name,
static inline void mutex_set_owner(struct mutex *lock)
{
- lock->owner = current_thread_info();
+ lock->owner = current;
}
static inline void mutex_clear_owner(struct mutex *lock)
diff --git a/kernel/mutex.c b/kernel/mutex.c
index c4195fa9890..2c938e2337c 100644
--- a/kernel/mutex.c
+++ b/kernel/mutex.c
@@ -160,14 +160,7 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
*/
for (;;) {
- struct thread_info *owner;
-
- /*
- * If we own the BKL, then don't spin. The owner of
- * the mutex might be waiting on us to release the BKL.
- */
- if (unlikely(current->lock_depth >= 0))
- break;
+ struct task_struct *owner;
/*
* If there's an owner, wait for it to either
diff --git a/kernel/mutex.h b/kernel/mutex.h
index 67578ca48f9..4115fbf83b1 100644
--- a/kernel/mutex.h
+++ b/kernel/mutex.h
@@ -19,7 +19,7 @@
#ifdef CONFIG_SMP
static inline void mutex_set_owner(struct mutex *lock)
{
- lock->owner = current_thread_info();
+ lock->owner = current;
}
static inline void mutex_clear_owner(struct mutex *lock)
diff --git a/kernel/params.c b/kernel/params.c
index 7ab388a48a2..ed72e133086 100644
--- a/kernel/params.c
+++ b/kernel/params.c
@@ -297,21 +297,15 @@ EXPORT_SYMBOL(param_ops_charp);
int param_set_bool(const char *val, const struct kernel_param *kp)
{
bool v;
+ int ret;
/* No equals means "set"... */
if (!val) val = "1";
/* One of =[yYnN01] */
- switch (val[0]) {
- case 'y': case 'Y': case '1':
- v = true;
- break;
- case 'n': case 'N': case '0':
- v = false;
- break;
- default:
- return -EINVAL;
- }
+ ret = strtobool(val, &v);
+ if (ret)
+ return ret;
if (kp->flags & KPARAM_ISBOOL)
*(bool *)kp->arg = v;
@@ -821,15 +815,18 @@ ssize_t __modver_version_show(struct module_attribute *mattr,
return sprintf(buf, "%s\n", vattr->version);
}
-extern struct module_version_attribute __start___modver[], __stop___modver[];
+extern const struct module_version_attribute *__start___modver[];
+extern const struct module_version_attribute *__stop___modver[];
static void __init version_sysfs_builtin(void)
{
- const struct module_version_attribute *vattr;
+ const struct module_version_attribute **p;
struct module_kobject *mk;
int err;
- for (vattr = __start___modver; vattr < __stop___modver; vattr++) {
+ for (p = __start___modver; p < __stop___modver; p++) {
+ const struct module_version_attribute *vattr = *p;
+
mk = locate_module_kobject(vattr->module_name);
if (mk) {
err = sysfs_create_file(&mk->kobj, &vattr->mattr.attr);
diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig
index 6de9a8fc341..87f4d24b55b 100644
--- a/kernel/power/Kconfig
+++ b/kernel/power/Kconfig
@@ -125,12 +125,6 @@ config PM_DEBUG
code. This is helpful when debugging and reporting PM bugs, like
suspend support.
-config PM_VERBOSE
- bool "Verbose Power Management debugging"
- depends on PM_DEBUG
- ---help---
- This option enables verbose messages from the Power Management code.
-
config PM_ADVANCED_DEBUG
bool "Extra PM attributes in sysfs for low-level debugging/testing"
depends on PM_DEBUG
@@ -229,3 +223,7 @@ config PM_OPP
representing individual voltage domains and provides SOC
implementations a ready to use framework to manage OPPs.
For more information, read <file:Documentation/power/opp.txt>
+
+config PM_RUNTIME_CLK
+ def_bool y
+ depends on PM_RUNTIME && HAVE_CLK
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index 50aae660174..f9bec56d882 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -272,12 +272,7 @@ static int create_image(int platform_mode)
local_irq_disable();
- error = sysdev_suspend(PMSG_FREEZE);
- if (!error) {
- error = syscore_suspend();
- if (error)
- sysdev_resume();
- }
+ error = syscore_suspend();
if (error) {
printk(KERN_ERR "PM: Some system devices failed to power down, "
"aborting hibernation\n");
@@ -302,7 +297,6 @@ static int create_image(int platform_mode)
Power_up:
syscore_resume();
- sysdev_resume();
/* NOTE: dpm_resume_noirq() is just a resume() for devices
* that suspended with irqs off ... no overall powerup.
*/
@@ -333,20 +327,25 @@ static int create_image(int platform_mode)
int hibernation_snapshot(int platform_mode)
{
+ pm_message_t msg = PMSG_RECOVER;
int error;
error = platform_begin(platform_mode);
if (error)
goto Close;
+ error = dpm_prepare(PMSG_FREEZE);
+ if (error)
+ goto Complete_devices;
+
/* Preallocate image memory before shutting down devices. */
error = hibernate_preallocate_memory();
if (error)
- goto Close;
+ goto Complete_devices;
suspend_console();
pm_restrict_gfp_mask();
- error = dpm_suspend_start(PMSG_FREEZE);
+ error = dpm_suspend(PMSG_FREEZE);
if (error)
goto Recover_platform;
@@ -364,13 +363,17 @@ int hibernation_snapshot(int platform_mode)
if (error || !in_suspend)
swsusp_free();
- dpm_resume_end(in_suspend ?
- (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);
+ msg = in_suspend ? (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE;
+ dpm_resume(msg);
if (error || !in_suspend)
pm_restore_gfp_mask();
resume_console();
+
+ Complete_devices:
+ dpm_complete(msg);
+
Close:
platform_end(platform_mode);
return error;
@@ -409,12 +412,7 @@ static int resume_target_kernel(bool platform_mode)
local_irq_disable();
- error = sysdev_suspend(PMSG_QUIESCE);
- if (!error) {
- error = syscore_suspend();
- if (error)
- sysdev_resume();
- }
+ error = syscore_suspend();
if (error)
goto Enable_irqs;
@@ -442,7 +440,6 @@ static int resume_target_kernel(bool platform_mode)
touch_softlockup_watchdog();
syscore_resume();
- sysdev_resume();
Enable_irqs:
local_irq_enable();
@@ -528,7 +525,6 @@ int hibernation_platform_enter(void)
goto Platform_finish;
local_irq_disable();
- sysdev_suspend(PMSG_HIBERNATE);
syscore_suspend();
if (pm_wakeup_pending()) {
error = -EAGAIN;
@@ -541,7 +537,6 @@ int hibernation_platform_enter(void)
Power_up:
syscore_resume();
- sysdev_resume();
local_irq_enable();
enable_nonboot_cpus();
@@ -982,10 +977,33 @@ static ssize_t image_size_store(struct kobject *kobj, struct kobj_attribute *att
power_attr(image_size);
+static ssize_t reserved_size_show(struct kobject *kobj,
+ struct kobj_attribute *attr, char *buf)
+{
+ return sprintf(buf, "%lu\n", reserved_size);
+}
+
+static ssize_t reserved_size_store(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ const char *buf, size_t n)
+{
+ unsigned long size;
+
+ if (sscanf(buf, "%lu", &size) == 1) {
+ reserved_size = size;
+ return n;
+ }
+
+ return -EINVAL;
+}
+
+power_attr(reserved_size);
+
static struct attribute * g[] = {
&disk_attr.attr,
&resume_attr.attr,
&image_size_attr.attr,
+ &reserved_size_attr.attr,
NULL,
};
diff --git a/kernel/power/main.c b/kernel/power/main.c
index de9aef8742f..2981af4ce7c 100644
--- a/kernel/power/main.c
+++ b/kernel/power/main.c
@@ -337,6 +337,7 @@ static int __init pm_init(void)
if (error)
return error;
hibernate_image_size_init();
+ hibernate_reserved_size_init();
power_kobj = kobject_create_and_add("power", NULL);
if (!power_kobj)
return -ENOMEM;
diff --git a/kernel/power/power.h b/kernel/power/power.h
index 03634be55f6..9a00a0a2628 100644
--- a/kernel/power/power.h
+++ b/kernel/power/power.h
@@ -15,6 +15,7 @@ struct swsusp_info {
#ifdef CONFIG_HIBERNATION
/* kernel/power/snapshot.c */
+extern void __init hibernate_reserved_size_init(void);
extern void __init hibernate_image_size_init(void);
#ifdef CONFIG_ARCH_HIBERNATION_HEADER
@@ -55,6 +56,7 @@ extern int hibernation_platform_enter(void);
#else /* !CONFIG_HIBERNATION */
+static inline void hibernate_reserved_size_init(void) {}
static inline void hibernate_image_size_init(void) {}
#endif /* !CONFIG_HIBERNATION */
@@ -72,6 +74,8 @@ static struct kobj_attribute _name##_attr = { \
/* Preferred image size in bytes (default 500 MB) */
extern unsigned long image_size;
+/* Size of memory reserved for drivers (default SPARE_PAGES x PAGE_SIZE) */
+extern unsigned long reserved_size;
extern int in_suspend;
extern dev_t swsusp_resume_device;
extern sector_t swsusp_resume_block;
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index ca0aacc2487..ace55889f70 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -41,16 +41,28 @@ static void swsusp_set_page_forbidden(struct page *);
static void swsusp_unset_page_forbidden(struct page *);
/*
+ * Number of bytes to reserve for memory allocations made by device drivers
+ * from their ->freeze() and ->freeze_noirq() callbacks so that they don't
+ * cause image creation to fail (tunable via /sys/power/reserved_size).
+ */
+unsigned long reserved_size;
+
+void __init hibernate_reserved_size_init(void)
+{
+ reserved_size = SPARE_PAGES * PAGE_SIZE;
+}
+
+/*
* Preferred image size in bytes (tunable via /sys/power/image_size).
- * When it is set to N, the image creating code will do its best to
- * ensure the image size will not exceed N bytes, but if that is
- * impossible, it will try to create the smallest image possible.
+ * When it is set to N, swsusp will do its best to ensure the image
+ * size will not exceed N bytes, but if that is impossible, it will
+ * try to create the smallest image possible.
*/
unsigned long image_size;
void __init hibernate_image_size_init(void)
{
- image_size = (totalram_pages / 3) * PAGE_SIZE;
+ image_size = ((totalram_pages * 2) / 5) * PAGE_SIZE;
}
/* List of PBEs needed for restoring the pages that were allocated before
@@ -1263,11 +1275,13 @@ static unsigned long minimum_image_size(unsigned long saveable)
* frame in use. We also need a number of page frames to be free during
* hibernation for allocations made while saving the image and for device
* drivers, in case they need to allocate memory from their hibernation
- * callbacks (these two numbers are given by PAGES_FOR_IO and SPARE_PAGES,
- * respectively, both of which are rough estimates). To make this happen, we
- * compute the total number of available page frames and allocate at least
+ * callbacks (these two numbers are given by PAGES_FOR_IO (which is a rough
+ * estimate) and reserverd_size divided by PAGE_SIZE (which is tunable through
+ * /sys/power/reserved_size, respectively). To make this happen, we compute the
+ * total number of available page frames and allocate at least
*
- * ([page frames total] + PAGES_FOR_IO + [metadata pages]) / 2 + 2 * SPARE_PAGES
+ * ([page frames total] + PAGES_FOR_IO + [metadata pages]) / 2
+ * + 2 * DIV_ROUND_UP(reserved_size, PAGE_SIZE)
*
* of them, which corresponds to the maximum size of a hibernation image.
*
@@ -1322,7 +1336,8 @@ int hibernate_preallocate_memory(void)
count -= totalreserve_pages;
/* Compute the maximum number of saveable pages to leave in memory. */
- max_size = (count - (size + PAGES_FOR_IO)) / 2 - 2 * SPARE_PAGES;
+ max_size = (count - (size + PAGES_FOR_IO)) / 2
+ - 2 * DIV_ROUND_UP(reserved_size, PAGE_SIZE);
/* Compute the desired number of image pages specified by image_size. */
size = DIV_ROUND_UP(image_size, PAGE_SIZE);
if (size > max_size)
diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c
index 8935369d503..1c41ba21541 100644
--- a/kernel/power/suspend.c
+++ b/kernel/power/suspend.c
@@ -163,19 +163,13 @@ static int suspend_enter(suspend_state_t state)
arch_suspend_disable_irqs();
BUG_ON(!irqs_disabled());
- error = sysdev_suspend(PMSG_SUSPEND);
- if (!error) {
- error = syscore_suspend();
- if (error)
- sysdev_resume();
- }
+ error = syscore_suspend();
if (!error) {
if (!(suspend_test(TEST_CORE) || pm_wakeup_pending())) {
error = suspend_ops->enter(state);
events_check_enabled = false;
}
syscore_resume();
- sysdev_resume();
}
arch_suspend_enable_irqs();
@@ -216,7 +210,6 @@ int suspend_devices_and_enter(suspend_state_t state)
goto Close;
}
suspend_console();
- pm_restrict_gfp_mask();
suspend_test_start();
error = dpm_suspend_start(PMSG_SUSPEND);
if (error) {
@@ -227,13 +220,12 @@ int suspend_devices_and_enter(suspend_state_t state)
if (suspend_test(TEST_DEVICES))
goto Recover_platform;
- suspend_enter(state);
+ error = suspend_enter(state);
Resume_devices:
suspend_test_start();
dpm_resume_end(PMSG_RESUME);
suspend_test_finish("resume devices");
- pm_restore_gfp_mask();
resume_console();
Close:
if (suspend_ops->end)
@@ -294,7 +286,9 @@ int enter_state(suspend_state_t state)
goto Finish;
pr_debug("PM: Entering %s sleep\n", pm_states[state]);
+ pm_restrict_gfp_mask();
error = suspend_devices_and_enter(state);
+ pm_restore_gfp_mask();
Finish:
pr_debug("PM: Finishing wakeup.\n");
diff --git a/kernel/power/user.c b/kernel/power/user.c
index c36c3b9e8a8..7d02d33be69 100644
--- a/kernel/power/user.c
+++ b/kernel/power/user.c
@@ -135,8 +135,10 @@ static int snapshot_release(struct inode *inode, struct file *filp)
free_basic_memory_bitmaps();
data = filp->private_data;
free_all_swap_pages(data->swap);
- if (data->frozen)
+ if (data->frozen) {
+ pm_restore_gfp_mask();
thaw_processes();
+ }
pm_notifier_call_chain(data->mode == O_RDONLY ?
PM_POST_HIBERNATION : PM_POST_RESTORE);
atomic_inc(&snapshot_device_available);
@@ -379,6 +381,7 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd,
* PM_HIBERNATION_PREPARE
*/
error = suspend_devices_and_enter(PM_SUSPEND_MEM);
+ data->ready = 0;
break;
case SNAPSHOT_PLATFORM_SUPPORT:
diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 0fc1eed28d2..dc7ab65f3b3 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -22,6 +22,7 @@
#include <linux/syscalls.h>
#include <linux/uaccess.h>
#include <linux/regset.h>
+#include <linux/hw_breakpoint.h>
/*
@@ -879,3 +880,19 @@ asmlinkage long compat_sys_ptrace(compat_long_t request, compat_long_t pid,
return ret;
}
#endif /* CONFIG_COMPAT */
+
+#ifdef CONFIG_HAVE_HW_BREAKPOINT
+int ptrace_get_breakpoints(struct task_struct *tsk)
+{
+ if (atomic_inc_not_zero(&tsk->ptrace_bp_refcnt))
+ return 0;
+
+ return -1;
+}
+
+void ptrace_put_breakpoints(struct task_struct *tsk)
+{
+ if (atomic_dec_and_test(&tsk->ptrace_bp_refcnt))
+ flush_ptrace_hw_breakpoint(tsk);
+}
+#endif /* CONFIG_HAVE_HW_BREAKPOINT */
diff --git a/kernel/rcupdate.c b/kernel/rcupdate.c
index f3240e98792..7784bd216b6 100644
--- a/kernel/rcupdate.c
+++ b/kernel/rcupdate.c
@@ -142,10 +142,17 @@ static int rcuhead_fixup_init(void *addr, enum debug_obj_state state)
* Ensure that queued callbacks are all executed.
* If we detect that we are nested in a RCU read-side critical
* section, we should simply fail, otherwise we would deadlock.
+ * In !PREEMPT configurations, there is no way to tell if we are
+ * in a RCU read-side critical section or not, so we never
+ * attempt any fixup and just print a warning.
*/
+#ifndef CONFIG_PREEMPT
+ WARN_ON_ONCE(1);
+ return 0;
+#endif
if (rcu_preempt_depth() != 0 || preempt_count() != 0 ||
irqs_disabled()) {
- WARN_ON(1);
+ WARN_ON_ONCE(1);
return 0;
}
rcu_barrier();
@@ -184,10 +191,17 @@ static int rcuhead_fixup_activate(void *addr, enum debug_obj_state state)
* Ensure that queued callbacks are all executed.
* If we detect that we are nested in a RCU read-side critical
* section, we should simply fail, otherwise we would deadlock.
+ * In !PREEMPT configurations, there is no way to tell if we are
+ * in a RCU read-side critical section or not, so we never
+ * attempt any fixup and just print a warning.
*/
+#ifndef CONFIG_PREEMPT
+ WARN_ON_ONCE(1);
+ return 0;
+#endif
if (rcu_preempt_depth() != 0 || preempt_count() != 0 ||
irqs_disabled()) {
- WARN_ON(1);
+ WARN_ON_ONCE(1);
return 0;
}
rcu_barrier();
@@ -214,15 +228,17 @@ static int rcuhead_fixup_free(void *addr, enum debug_obj_state state)
* Ensure that queued callbacks are all executed.
* If we detect that we are nested in a RCU read-side critical
* section, we should simply fail, otherwise we would deadlock.
- * Note that the machinery to reliably determine whether
- * or not we are in an RCU read-side critical section
- * exists only in the preemptible RCU implementations
- * (TINY_PREEMPT_RCU and TREE_PREEMPT_RCU), which is why
- * DEBUG_OBJECTS_RCU_HEAD is disallowed if !PREEMPT.
+ * In !PREEMPT configurations, there is no way to tell if we are
+ * in a RCU read-side critical section or not, so we never
+ * attempt any fixup and just print a warning.
*/
+#ifndef CONFIG_PREEMPT
+ WARN_ON_ONCE(1);
+ return 0;
+#endif
if (rcu_preempt_depth() != 0 || preempt_count() != 0 ||
irqs_disabled()) {
- WARN_ON(1);
+ WARN_ON_ONCE(1);
return 0;
}
rcu_barrier();
diff --git a/kernel/rcutiny.c b/kernel/rcutiny.c
index 0c343b9a46d..421abfd3641 100644
--- a/kernel/rcutiny.c
+++ b/kernel/rcutiny.c
@@ -40,10 +40,10 @@
static struct task_struct *rcu_kthread_task;
static DECLARE_WAIT_QUEUE_HEAD(rcu_kthread_wq);
static unsigned long have_rcu_kthread_work;
-static void invoke_rcu_kthread(void);
/* Forward declarations for rcutiny_plugin.h. */
struct rcu_ctrlblk;
+static void invoke_rcu_kthread(void);
static void rcu_process_callbacks(struct rcu_ctrlblk *rcp);
static int rcu_kthread(void *arg);
static void __call_rcu(struct rcu_head *head,
@@ -79,36 +79,45 @@ void rcu_exit_nohz(void)
#endif /* #ifdef CONFIG_NO_HZ */
/*
- * Helper function for rcu_qsctr_inc() and rcu_bh_qsctr_inc().
- * Also disable irqs to avoid confusion due to interrupt handlers
+ * Helper function for rcu_sched_qs() and rcu_bh_qs().
+ * Also irqs are disabled to avoid confusion due to interrupt handlers
* invoking call_rcu().
*/
static int rcu_qsctr_help(struct rcu_ctrlblk *rcp)
{
- unsigned long flags;
-
- local_irq_save(flags);
if (rcp->rcucblist != NULL &&
rcp->donetail != rcp->curtail) {
rcp->donetail = rcp->curtail;
- local_irq_restore(flags);
return 1;
}
- local_irq_restore(flags);
return 0;
}
/*
+ * Wake up rcu_kthread() to process callbacks now eligible for invocation
+ * or to boost readers.
+ */
+static void invoke_rcu_kthread(void)
+{
+ have_rcu_kthread_work = 1;
+ wake_up(&rcu_kthread_wq);
+}
+
+/*
* Record an rcu quiescent state. And an rcu_bh quiescent state while we
* are at it, given that any rcu quiescent state is also an rcu_bh
* quiescent state. Use "+" instead of "||" to defeat short circuiting.
*/
void rcu_sched_qs(int cpu)
{
+ unsigned long flags;
+
+ local_irq_save(flags);
if (rcu_qsctr_help(&rcu_sched_ctrlblk) +
rcu_qsctr_help(&rcu_bh_ctrlblk))
invoke_rcu_kthread();
+ local_irq_restore(flags);
}
/*
@@ -116,8 +125,12 @@ void rcu_sched_qs(int cpu)
*/
void rcu_bh_qs(int cpu)
{
+ unsigned long flags;
+
+ local_irq_save(flags);
if (rcu_qsctr_help(&rcu_bh_ctrlblk))
invoke_rcu_kthread();
+ local_irq_restore(flags);
}
/*
@@ -167,7 +180,7 @@ static void rcu_process_callbacks(struct rcu_ctrlblk *rcp)
prefetch(next);
debug_rcu_head_unqueue(list);
local_bh_disable();
- list->func(list);
+ __rcu_reclaim(list);
local_bh_enable();
list = next;
RCU_TRACE(cb_count++);
@@ -208,20 +221,6 @@ static int rcu_kthread(void *arg)
}
/*
- * Wake up rcu_kthread() to process callbacks now eligible for invocation
- * or to boost readers.
- */
-static void invoke_rcu_kthread(void)
-{
- unsigned long flags;
-
- local_irq_save(flags);
- have_rcu_kthread_work = 1;
- wake_up(&rcu_kthread_wq);
- local_irq_restore(flags);
-}
-
-/*
* Wait for a grace period to elapse. But it is illegal to invoke
* synchronize_sched() from within an RCU read-side critical section.
* Therefore, any legal call to synchronize_sched() is a quiescent
diff --git a/kernel/rcutiny_plugin.h b/kernel/rcutiny_plugin.h
index 3cb8e362e88..f259c676195 100644
--- a/kernel/rcutiny_plugin.h
+++ b/kernel/rcutiny_plugin.h
@@ -100,23 +100,28 @@ struct rcu_preempt_ctrlblk {
u8 completed; /* Last grace period completed. */
/* If all three are equal, RCU is idle. */
#ifdef CONFIG_RCU_BOOST
- s8 boosted_this_gp; /* Has boosting already happened? */
unsigned long boost_time; /* When to start boosting (jiffies) */
#endif /* #ifdef CONFIG_RCU_BOOST */
#ifdef CONFIG_RCU_TRACE
unsigned long n_grace_periods;
#ifdef CONFIG_RCU_BOOST
unsigned long n_tasks_boosted;
+ /* Total number of tasks boosted. */
unsigned long n_exp_boosts;
+ /* Number of tasks boosted for expedited GP. */
unsigned long n_normal_boosts;
- unsigned long n_normal_balk_blkd_tasks;
- unsigned long n_normal_balk_gp_tasks;
- unsigned long n_normal_balk_boost_tasks;
- unsigned long n_normal_balk_boosted;
- unsigned long n_normal_balk_notyet;
- unsigned long n_normal_balk_nos;
- unsigned long n_exp_balk_blkd_tasks;
- unsigned long n_exp_balk_nos;
+ /* Number of tasks boosted for normal GP. */
+ unsigned long n_balk_blkd_tasks;
+ /* Refused to boost: no blocked tasks. */
+ unsigned long n_balk_exp_gp_tasks;
+ /* Refused to boost: nothing blocking GP. */
+ unsigned long n_balk_boost_tasks;
+ /* Refused to boost: already boosting. */
+ unsigned long n_balk_notyet;
+ /* Refused to boost: not yet time. */
+ unsigned long n_balk_nos;
+ /* Refused to boost: not sure why, though. */
+ /* This can happen due to race conditions. */
#endif /* #ifdef CONFIG_RCU_BOOST */
#endif /* #ifdef CONFIG_RCU_TRACE */
};
@@ -201,7 +206,6 @@ static struct list_head *rcu_next_node_entry(struct task_struct *t)
#ifdef CONFIG_RCU_BOOST
static void rcu_initiate_boost_trace(void);
-static void rcu_initiate_exp_boost_trace(void);
#endif /* #ifdef CONFIG_RCU_BOOST */
/*
@@ -219,41 +223,21 @@ static void show_tiny_preempt_stats(struct seq_file *m)
"N."[!rcu_preempt_ctrlblk.gp_tasks],
"E."[!rcu_preempt_ctrlblk.exp_tasks]);
#ifdef CONFIG_RCU_BOOST
- seq_printf(m, " ttb=%c btg=",
- "B."[!rcu_preempt_ctrlblk.boost_tasks]);
- switch (rcu_preempt_ctrlblk.boosted_this_gp) {
- case -1:
- seq_puts(m, "exp");
- break;
- case 0:
- seq_puts(m, "no");
- break;
- case 1:
- seq_puts(m, "begun");
- break;
- case 2:
- seq_puts(m, "done");
- break;
- default:
- seq_printf(m, "?%d?", rcu_preempt_ctrlblk.boosted_this_gp);
- }
- seq_printf(m, " ntb=%lu neb=%lu nnb=%lu j=%04x bt=%04x\n",
+ seq_printf(m, "%sttb=%c ntb=%lu neb=%lu nnb=%lu j=%04x bt=%04x\n",
+ " ",
+ "B."[!rcu_preempt_ctrlblk.boost_tasks],
rcu_preempt_ctrlblk.n_tasks_boosted,
rcu_preempt_ctrlblk.n_exp_boosts,
rcu_preempt_ctrlblk.n_normal_boosts,
(int)(jiffies & 0xffff),
(int)(rcu_preempt_ctrlblk.boost_time & 0xffff));
- seq_printf(m, " %s: nt=%lu gt=%lu bt=%lu b=%lu ny=%lu nos=%lu\n",
- "normal balk",
- rcu_preempt_ctrlblk.n_normal_balk_blkd_tasks,
- rcu_preempt_ctrlblk.n_normal_balk_gp_tasks,
- rcu_preempt_ctrlblk.n_normal_balk_boost_tasks,
- rcu_preempt_ctrlblk.n_normal_balk_boosted,
- rcu_preempt_ctrlblk.n_normal_balk_notyet,
- rcu_preempt_ctrlblk.n_normal_balk_nos);
- seq_printf(m, " exp balk: bt=%lu nos=%lu\n",
- rcu_preempt_ctrlblk.n_exp_balk_blkd_tasks,
- rcu_preempt_ctrlblk.n_exp_balk_nos);
+ seq_printf(m, "%s: nt=%lu egt=%lu bt=%lu ny=%lu nos=%lu\n",
+ " balk",
+ rcu_preempt_ctrlblk.n_balk_blkd_tasks,
+ rcu_preempt_ctrlblk.n_balk_exp_gp_tasks,
+ rcu_preempt_ctrlblk.n_balk_boost_tasks,
+ rcu_preempt_ctrlblk.n_balk_notyet,
+ rcu_preempt_ctrlblk.n_balk_nos);
#endif /* #ifdef CONFIG_RCU_BOOST */
}
@@ -271,25 +255,59 @@ static int rcu_boost(void)
{
unsigned long flags;
struct rt_mutex mtx;
- struct list_head *np;
struct task_struct *t;
+ struct list_head *tb;
- if (rcu_preempt_ctrlblk.boost_tasks == NULL)
+ if (rcu_preempt_ctrlblk.boost_tasks == NULL &&
+ rcu_preempt_ctrlblk.exp_tasks == NULL)
return 0; /* Nothing to boost. */
+
raw_local_irq_save(flags);
- rcu_preempt_ctrlblk.boosted_this_gp++;
- t = container_of(rcu_preempt_ctrlblk.boost_tasks, struct task_struct,
- rcu_node_entry);
- np = rcu_next_node_entry(t);
+
+ /*
+ * Recheck with irqs disabled: all tasks in need of boosting
+ * might exit their RCU read-side critical sections on their own
+ * if we are preempted just before disabling irqs.
+ */
+ if (rcu_preempt_ctrlblk.boost_tasks == NULL &&
+ rcu_preempt_ctrlblk.exp_tasks == NULL) {
+ raw_local_irq_restore(flags);
+ return 0;
+ }
+
+ /*
+ * Preferentially boost tasks blocking expedited grace periods.
+ * This cannot starve the normal grace periods because a second
+ * expedited grace period must boost all blocked tasks, including
+ * those blocking the pre-existing normal grace period.
+ */
+ if (rcu_preempt_ctrlblk.exp_tasks != NULL) {
+ tb = rcu_preempt_ctrlblk.exp_tasks;
+ RCU_TRACE(rcu_preempt_ctrlblk.n_exp_boosts++);
+ } else {
+ tb = rcu_preempt_ctrlblk.boost_tasks;
+ RCU_TRACE(rcu_preempt_ctrlblk.n_normal_boosts++);
+ }
+ RCU_TRACE(rcu_preempt_ctrlblk.n_tasks_boosted++);
+
+ /*
+ * We boost task t by manufacturing an rt_mutex that appears to
+ * be held by task t. We leave a pointer to that rt_mutex where
+ * task t can find it, and task t will release the mutex when it
+ * exits its outermost RCU read-side critical section. Then
+ * simply acquiring this artificial rt_mutex will boost task
+ * t's priority. (Thanks to tglx for suggesting this approach!)
+ */
+ t = container_of(tb, struct task_struct, rcu_node_entry);
rt_mutex_init_proxy_locked(&mtx, t);
t->rcu_boost_mutex = &mtx;
t->rcu_read_unlock_special |= RCU_READ_UNLOCK_BOOSTED;
raw_local_irq_restore(flags);
rt_mutex_lock(&mtx);
- RCU_TRACE(rcu_preempt_ctrlblk.n_tasks_boosted++);
- rcu_preempt_ctrlblk.boosted_this_gp++;
- rt_mutex_unlock(&mtx);
- return rcu_preempt_ctrlblk.boost_tasks != NULL;
+ rt_mutex_unlock(&mtx); /* Keep lockdep happy. */
+
+ return rcu_preempt_ctrlblk.boost_tasks != NULL ||
+ rcu_preempt_ctrlblk.exp_tasks != NULL;
}
/*
@@ -304,42 +322,25 @@ static int rcu_boost(void)
*/
static int rcu_initiate_boost(void)
{
- if (!rcu_preempt_blocked_readers_cgp()) {
- RCU_TRACE(rcu_preempt_ctrlblk.n_normal_balk_blkd_tasks++);
+ if (!rcu_preempt_blocked_readers_cgp() &&
+ rcu_preempt_ctrlblk.exp_tasks == NULL) {
+ RCU_TRACE(rcu_preempt_ctrlblk.n_balk_exp_gp_tasks++);
return 0;
}
- if (rcu_preempt_ctrlblk.gp_tasks != NULL &&
- rcu_preempt_ctrlblk.boost_tasks == NULL &&
- rcu_preempt_ctrlblk.boosted_this_gp == 0 &&
- ULONG_CMP_GE(jiffies, rcu_preempt_ctrlblk.boost_time)) {
- rcu_preempt_ctrlblk.boost_tasks = rcu_preempt_ctrlblk.gp_tasks;
+ if (rcu_preempt_ctrlblk.exp_tasks != NULL ||
+ (rcu_preempt_ctrlblk.gp_tasks != NULL &&
+ rcu_preempt_ctrlblk.boost_tasks == NULL &&
+ ULONG_CMP_GE(jiffies, rcu_preempt_ctrlblk.boost_time))) {
+ if (rcu_preempt_ctrlblk.exp_tasks == NULL)
+ rcu_preempt_ctrlblk.boost_tasks =
+ rcu_preempt_ctrlblk.gp_tasks;
invoke_rcu_kthread();
- RCU_TRACE(rcu_preempt_ctrlblk.n_normal_boosts++);
} else
RCU_TRACE(rcu_initiate_boost_trace());
return 1;
}
-/*
- * Initiate boosting for an expedited grace period.
- */
-static void rcu_initiate_expedited_boost(void)
-{
- unsigned long flags;
-
- raw_local_irq_save(flags);
- if (!list_empty(&rcu_preempt_ctrlblk.blkd_tasks)) {
- rcu_preempt_ctrlblk.boost_tasks =
- rcu_preempt_ctrlblk.blkd_tasks.next;
- rcu_preempt_ctrlblk.boosted_this_gp = -1;
- invoke_rcu_kthread();
- RCU_TRACE(rcu_preempt_ctrlblk.n_exp_boosts++);
- } else
- RCU_TRACE(rcu_initiate_exp_boost_trace());
- raw_local_irq_restore(flags);
-}
-
-#define RCU_BOOST_DELAY_JIFFIES DIV_ROUND_UP(CONFIG_RCU_BOOST_DELAY * HZ, 1000);
+#define RCU_BOOST_DELAY_JIFFIES DIV_ROUND_UP(CONFIG_RCU_BOOST_DELAY * HZ, 1000)
/*
* Do priority-boost accounting for the start of a new grace period.
@@ -347,8 +348,6 @@ static void rcu_initiate_expedited_boost(void)
static void rcu_preempt_boost_start_gp(void)
{
rcu_preempt_ctrlblk.boost_time = jiffies + RCU_BOOST_DELAY_JIFFIES;
- if (rcu_preempt_ctrlblk.boosted_this_gp > 0)
- rcu_preempt_ctrlblk.boosted_this_gp = 0;
}
#else /* #ifdef CONFIG_RCU_BOOST */
@@ -372,13 +371,6 @@ static int rcu_initiate_boost(void)
}
/*
- * If there is no RCU priority boosting, we don't initiate expedited boosting.
- */
-static void rcu_initiate_expedited_boost(void)
-{
-}
-
-/*
* If there is no RCU priority boosting, nothing to do at grace-period start.
*/
static void rcu_preempt_boost_start_gp(void)
@@ -418,7 +410,7 @@ static void rcu_preempt_cpu_qs(void)
if (!rcu_preempt_gp_in_progress())
return;
/*
- * Check up on boosting. If there are no readers blocking the
+ * Check up on boosting. If there are readers blocking the
* current grace period, leave.
*/
if (rcu_initiate_boost())
@@ -578,7 +570,7 @@ static void rcu_read_unlock_special(struct task_struct *t)
empty = !rcu_preempt_blocked_readers_cgp();
empty_exp = rcu_preempt_ctrlblk.exp_tasks == NULL;
np = rcu_next_node_entry(t);
- list_del(&t->rcu_node_entry);
+ list_del_init(&t->rcu_node_entry);
if (&t->rcu_node_entry == rcu_preempt_ctrlblk.gp_tasks)
rcu_preempt_ctrlblk.gp_tasks = np;
if (&t->rcu_node_entry == rcu_preempt_ctrlblk.exp_tasks)
@@ -587,7 +579,6 @@ static void rcu_read_unlock_special(struct task_struct *t)
if (&t->rcu_node_entry == rcu_preempt_ctrlblk.boost_tasks)
rcu_preempt_ctrlblk.boost_tasks = np;
#endif /* #ifdef CONFIG_RCU_BOOST */
- INIT_LIST_HEAD(&t->rcu_node_entry);
/*
* If this was the last task on the current list, and if
@@ -812,13 +803,16 @@ void synchronize_rcu_expedited(void)
rpcp->exp_tasks = rpcp->blkd_tasks.next;
if (rpcp->exp_tasks == &rpcp->blkd_tasks)
rpcp->exp_tasks = NULL;
- local_irq_restore(flags);
/* Wait for tail of ->blkd_tasks list to drain. */
- if (rcu_preempted_readers_exp())
- rcu_initiate_expedited_boost();
+ if (!rcu_preempted_readers_exp())
+ local_irq_restore(flags);
+ else {
+ rcu_initiate_boost();
+ local_irq_restore(flags);
wait_event(sync_rcu_preempt_exp_wq,
!rcu_preempted_readers_exp());
+ }
/* Clean up and exit. */
barrier(); /* ensure expedited GP seen before counter increment. */
@@ -931,24 +925,17 @@ void __init rcu_scheduler_starting(void)
static void rcu_initiate_boost_trace(void)
{
- if (rcu_preempt_ctrlblk.gp_tasks == NULL)
- rcu_preempt_ctrlblk.n_normal_balk_gp_tasks++;
+ if (list_empty(&rcu_preempt_ctrlblk.blkd_tasks))
+ rcu_preempt_ctrlblk.n_balk_blkd_tasks++;
+ else if (rcu_preempt_ctrlblk.gp_tasks == NULL &&
+ rcu_preempt_ctrlblk.exp_tasks == NULL)
+ rcu_preempt_ctrlblk.n_balk_exp_gp_tasks++;
else if (rcu_preempt_ctrlblk.boost_tasks != NULL)
- rcu_preempt_ctrlblk.n_normal_balk_boost_tasks++;
- else if (rcu_preempt_ctrlblk.boosted_this_gp != 0)
- rcu_preempt_ctrlblk.n_normal_balk_boosted++;
+ rcu_preempt_ctrlblk.n_balk_boost_tasks++;
else if (!ULONG_CMP_GE(jiffies, rcu_preempt_ctrlblk.boost_time))
- rcu_preempt_ctrlblk.n_normal_balk_notyet++;
- else
- rcu_preempt_ctrlblk.n_normal_balk_nos++;
-}
-
-static void rcu_initiate_exp_boost_trace(void)
-{
- if (list_empty(&rcu_preempt_ctrlblk.blkd_tasks))
- rcu_preempt_ctrlblk.n_exp_balk_blkd_tasks++;
+ rcu_preempt_ctrlblk.n_balk_notyet++;
else
- rcu_preempt_ctrlblk.n_exp_balk_nos++;
+ rcu_preempt_ctrlblk.n_balk_nos++;
}
#endif /* #ifdef CONFIG_RCU_BOOST */
diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c
index c224da41890..2e138db0338 100644
--- a/kernel/rcutorture.c
+++ b/kernel/rcutorture.c
@@ -131,7 +131,7 @@ struct rcu_torture {
static LIST_HEAD(rcu_torture_freelist);
static struct rcu_torture __rcu *rcu_torture_current;
-static long rcu_torture_current_version;
+static unsigned long rcu_torture_current_version;
static struct rcu_torture rcu_tortures[10 * RCU_TORTURE_PIPE_LEN];
static DEFINE_SPINLOCK(rcu_torture_lock);
static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_count) =
@@ -146,8 +146,6 @@ static atomic_t n_rcu_torture_mberror;
static atomic_t n_rcu_torture_error;
static long n_rcu_torture_boost_ktrerror;
static long n_rcu_torture_boost_rterror;
-static long n_rcu_torture_boost_allocerror;
-static long n_rcu_torture_boost_afferror;
static long n_rcu_torture_boost_failure;
static long n_rcu_torture_boosts;
static long n_rcu_torture_timers;
@@ -163,11 +161,11 @@ static int stutter_pause_test;
#endif
int rcutorture_runnable = RCUTORTURE_RUNNABLE_INIT;
-#ifdef CONFIG_RCU_BOOST
+#if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU)
#define rcu_can_boost() 1
-#else /* #ifdef CONFIG_RCU_BOOST */
+#else /* #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) */
#define rcu_can_boost() 0
-#endif /* #else #ifdef CONFIG_RCU_BOOST */
+#endif /* #else #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) */
static unsigned long boost_starttime; /* jiffies of next boost test start. */
DEFINE_MUTEX(boost_mutex); /* protect setting boost_starttime */
@@ -751,6 +749,7 @@ static int rcu_torture_boost(void *arg)
n_rcu_torture_boost_rterror++;
}
+ init_rcu_head_on_stack(&rbi.rcu);
/* Each pass through the following loop does one boost-test cycle. */
do {
/* Wait for the next test interval. */
@@ -810,6 +809,7 @@ checkwait: rcu_stutter_wait("rcu_torture_boost");
/* Clean up and exit. */
VERBOSE_PRINTK_STRING("rcu_torture_boost task stopping");
+ destroy_rcu_head_on_stack(&rbi.rcu);
rcutorture_shutdown_absorb("rcu_torture_boost");
while (!kthread_should_stop() || rbi.inflight)
schedule_timeout_uninterruptible(1);
@@ -886,7 +886,7 @@ rcu_torture_writer(void *arg)
old_rp->rtort_pipe_count++;
cur_ops->deferred_free(old_rp);
}
- rcu_torture_current_version++;
+ rcutorture_record_progress(++rcu_torture_current_version);
oldbatch = cur_ops->completed();
rcu_stutter_wait("rcu_torture_writer");
} while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP);
@@ -1066,8 +1066,8 @@ rcu_torture_printk(char *page)
}
cnt += sprintf(&page[cnt], "%s%s ", torture_type, TORTURE_FLAG);
cnt += sprintf(&page[cnt],
- "rtc: %p ver: %ld tfle: %d rta: %d rtaf: %d rtf: %d "
- "rtmbe: %d rtbke: %ld rtbre: %ld rtbae: %ld rtbafe: %ld "
+ "rtc: %p ver: %lu tfle: %d rta: %d rtaf: %d rtf: %d "
+ "rtmbe: %d rtbke: %ld rtbre: %ld "
"rtbf: %ld rtb: %ld nt: %ld",
rcu_torture_current,
rcu_torture_current_version,
@@ -1078,16 +1078,12 @@ rcu_torture_printk(char *page)
atomic_read(&n_rcu_torture_mberror),
n_rcu_torture_boost_ktrerror,
n_rcu_torture_boost_rterror,
- n_rcu_torture_boost_allocerror,
- n_rcu_torture_boost_afferror,
n_rcu_torture_boost_failure,
n_rcu_torture_boosts,
n_rcu_torture_timers);
if (atomic_read(&n_rcu_torture_mberror) != 0 ||
n_rcu_torture_boost_ktrerror != 0 ||
n_rcu_torture_boost_rterror != 0 ||
- n_rcu_torture_boost_allocerror != 0 ||
- n_rcu_torture_boost_afferror != 0 ||
n_rcu_torture_boost_failure != 0)
cnt += sprintf(&page[cnt], " !!!");
cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG);
@@ -1331,6 +1327,7 @@ rcu_torture_cleanup(void)
int i;
mutex_lock(&fullstop_mutex);
+ rcutorture_record_test_transition();
if (fullstop == FULLSTOP_SHUTDOWN) {
printk(KERN_WARNING /* but going down anyway, so... */
"Concurrent 'rmmod rcutorture' and shutdown illegal!\n");
@@ -1486,8 +1483,6 @@ rcu_torture_init(void)
atomic_set(&n_rcu_torture_error, 0);
n_rcu_torture_boost_ktrerror = 0;
n_rcu_torture_boost_rterror = 0;
- n_rcu_torture_boost_allocerror = 0;
- n_rcu_torture_boost_afferror = 0;
n_rcu_torture_boost_failure = 0;
n_rcu_torture_boosts = 0;
for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++)
@@ -1624,6 +1619,7 @@ rcu_torture_init(void)
}
}
register_reboot_notifier(&rcutorture_shutdown_nb);
+ rcutorture_record_test_transition();
mutex_unlock(&fullstop_mutex);
return 0;
diff --git a/kernel/rcutree.c b/kernel/rcutree.c
index dd4aea806f8..e486f7c3ffb 100644
--- a/kernel/rcutree.c
+++ b/kernel/rcutree.c
@@ -47,6 +47,8 @@
#include <linux/mutex.h>
#include <linux/time.h>
#include <linux/kernel_stat.h>
+#include <linux/wait.h>
+#include <linux/kthread.h>
#include "rcutree.h"
@@ -79,10 +81,41 @@ DEFINE_PER_CPU(struct rcu_data, rcu_sched_data);
struct rcu_state rcu_bh_state = RCU_STATE_INITIALIZER(rcu_bh_state);
DEFINE_PER_CPU(struct rcu_data, rcu_bh_data);
+static struct rcu_state *rcu_state;
+
int rcu_scheduler_active __read_mostly;
EXPORT_SYMBOL_GPL(rcu_scheduler_active);
/*
+ * Control variables for per-CPU and per-rcu_node kthreads. These
+ * handle all flavors of RCU.
+ */
+static DEFINE_PER_CPU(struct task_struct *, rcu_cpu_kthread_task);
+DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_status);
+DEFINE_PER_CPU(int, rcu_cpu_kthread_cpu);
+DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_loops);
+static DEFINE_PER_CPU(wait_queue_head_t, rcu_cpu_wq);
+DEFINE_PER_CPU(char, rcu_cpu_has_work);
+static char rcu_kthreads_spawnable;
+
+static void rcu_node_kthread_setaffinity(struct rcu_node *rnp, int outgoingcpu);
+static void invoke_rcu_cpu_kthread(void);
+
+#define RCU_KTHREAD_PRIO 1 /* RT priority for per-CPU kthreads. */
+
+/*
+ * Track the rcutorture test sequence number and the update version
+ * number within a given test. The rcutorture_testseq is incremented
+ * on every rcutorture module load and unload, so has an odd value
+ * when a test is running. The rcutorture_vernum is set to zero
+ * when rcutorture starts and is incremented on each rcutorture update.
+ * These variables enable correlating rcutorture output with the
+ * RCU tracing information.
+ */
+unsigned long rcutorture_testseq;
+unsigned long rcutorture_vernum;
+
+/*
* Return true if an RCU grace period is in progress. The ACCESS_ONCE()s
* permit this function to be invoked without holding the root rcu_node
* structure's ->lock, but of course results can be subject to change.
@@ -124,6 +157,7 @@ void rcu_note_context_switch(int cpu)
rcu_sched_qs(cpu);
rcu_preempt_note_context_switch(cpu);
}
+EXPORT_SYMBOL_GPL(rcu_note_context_switch);
#ifdef CONFIG_NO_HZ
DEFINE_PER_CPU(struct rcu_dynticks, rcu_dynticks) = {
@@ -140,10 +174,8 @@ module_param(blimit, int, 0);
module_param(qhimark, int, 0);
module_param(qlowmark, int, 0);
-#ifdef CONFIG_RCU_CPU_STALL_DETECTOR
-int rcu_cpu_stall_suppress __read_mostly = RCU_CPU_STALL_SUPPRESS_INIT;
+int rcu_cpu_stall_suppress __read_mostly;
module_param(rcu_cpu_stall_suppress, int, 0644);
-#endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
static void force_quiescent_state(struct rcu_state *rsp, int relaxed);
static int rcu_pending(int cpu);
@@ -176,6 +208,31 @@ void rcu_bh_force_quiescent_state(void)
EXPORT_SYMBOL_GPL(rcu_bh_force_quiescent_state);
/*
+ * Record the number of times rcutorture tests have been initiated and
+ * terminated. This information allows the debugfs tracing stats to be
+ * correlated to the rcutorture messages, even when the rcutorture module
+ * is being repeatedly loaded and unloaded. In other words, we cannot
+ * store this state in rcutorture itself.
+ */
+void rcutorture_record_test_transition(void)
+{
+ rcutorture_testseq++;
+ rcutorture_vernum = 0;
+}
+EXPORT_SYMBOL_GPL(rcutorture_record_test_transition);
+
+/*
+ * Record the number of writer passes through the current rcutorture test.
+ * This is also used to correlate debugfs tracing stats with the rcutorture
+ * messages.
+ */
+void rcutorture_record_progress(unsigned long vernum)
+{
+ rcutorture_vernum++;
+}
+EXPORT_SYMBOL_GPL(rcutorture_record_progress);
+
+/*
* Force a quiescent state for RCU-sched.
*/
void rcu_sched_force_quiescent_state(void)
@@ -234,8 +291,8 @@ static int rcu_implicit_offline_qs(struct rcu_data *rdp)
return 1;
}
- /* If preemptable RCU, no point in sending reschedule IPI. */
- if (rdp->preemptable)
+ /* If preemptible RCU, no point in sending reschedule IPI. */
+ if (rdp->preemptible)
return 0;
/* The CPU is online, so send it a reschedule IPI. */
@@ -450,8 +507,6 @@ static int rcu_implicit_dynticks_qs(struct rcu_data *rdp)
#endif /* #else #ifdef CONFIG_NO_HZ */
-#ifdef CONFIG_RCU_CPU_STALL_DETECTOR
-
int rcu_cpu_stall_suppress __read_mostly;
static void record_gp_stall_check_time(struct rcu_state *rsp)
@@ -537,21 +592,24 @@ static void print_cpu_stall(struct rcu_state *rsp)
static void check_cpu_stall(struct rcu_state *rsp, struct rcu_data *rdp)
{
- long delta;
+ unsigned long j;
+ unsigned long js;
struct rcu_node *rnp;
if (rcu_cpu_stall_suppress)
return;
- delta = jiffies - ACCESS_ONCE(rsp->jiffies_stall);
+ j = ACCESS_ONCE(jiffies);
+ js = ACCESS_ONCE(rsp->jiffies_stall);
rnp = rdp->mynode;
- if ((ACCESS_ONCE(rnp->qsmask) & rdp->grpmask) && delta >= 0) {
+ if ((ACCESS_ONCE(rnp->qsmask) & rdp->grpmask) && ULONG_CMP_GE(j, js)) {
/* We haven't checked in, so go dump stack. */
print_cpu_stall(rsp);
- } else if (rcu_gp_in_progress(rsp) && delta >= RCU_STALL_RAT_DELAY) {
+ } else if (rcu_gp_in_progress(rsp) &&
+ ULONG_CMP_GE(j, js + RCU_STALL_RAT_DELAY)) {
- /* They had two time units to dump stack, so complain. */
+ /* They had a few time units to dump stack, so complain. */
print_other_cpu_stall(rsp);
}
}
@@ -587,26 +645,6 @@ static void __init check_cpu_stall_init(void)
atomic_notifier_chain_register(&panic_notifier_list, &rcu_panic_block);
}
-#else /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
-
-static void record_gp_stall_check_time(struct rcu_state *rsp)
-{
-}
-
-static void check_cpu_stall(struct rcu_state *rsp, struct rcu_data *rdp)
-{
-}
-
-void rcu_cpu_stall_reset(void)
-{
-}
-
-static void __init check_cpu_stall_init(void)
-{
-}
-
-#endif /* #else #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
-
/*
* Update CPU-local rcu_data state to record the newly noticed grace period.
* This is used both when we started the grace period and when we notice
@@ -809,6 +847,7 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags)
rnp->completed = rsp->completed;
rsp->signaled = RCU_SIGNAL_INIT; /* force_quiescent_state OK. */
rcu_start_gp_per_cpu(rsp, rnp, rdp);
+ rcu_preempt_boost_start_gp(rnp);
raw_spin_unlock_irqrestore(&rnp->lock, flags);
return;
}
@@ -844,6 +883,7 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags)
rnp->completed = rsp->completed;
if (rnp == rdp->mynode)
rcu_start_gp_per_cpu(rsp, rnp, rdp);
+ rcu_preempt_boost_start_gp(rnp);
raw_spin_unlock(&rnp->lock); /* irqs remain disabled. */
}
@@ -864,7 +904,12 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags)
static void rcu_report_qs_rsp(struct rcu_state *rsp, unsigned long flags)
__releases(rcu_get_root(rsp)->lock)
{
+ unsigned long gp_duration;
+
WARN_ON_ONCE(!rcu_gp_in_progress(rsp));
+ gp_duration = jiffies - rsp->gp_start;
+ if (gp_duration > rsp->gp_max)
+ rsp->gp_max = gp_duration;
rsp->completed = rsp->gpnum;
rsp->signaled = RCU_GP_IDLE;
rcu_start_gp(rsp, flags); /* releases root node's rnp->lock. */
@@ -894,7 +939,7 @@ rcu_report_qs_rnp(unsigned long mask, struct rcu_state *rsp,
return;
}
rnp->qsmask &= ~mask;
- if (rnp->qsmask != 0 || rcu_preempted_readers(rnp)) {
+ if (rnp->qsmask != 0 || rcu_preempt_blocked_readers_cgp(rnp)) {
/* Other bits still set at this level, so done. */
raw_spin_unlock_irqrestore(&rnp->lock, flags);
@@ -1037,6 +1082,8 @@ static void rcu_send_cbs_to_online(struct rcu_state *rsp)
/*
* Remove the outgoing CPU from the bitmasks in the rcu_node hierarchy
* and move all callbacks from the outgoing CPU to the current one.
+ * There can only be one CPU hotplug operation at a time, so no other
+ * CPU can be attempting to update rcu_cpu_kthread_task.
*/
static void __rcu_offline_cpu(int cpu, struct rcu_state *rsp)
{
@@ -1045,6 +1092,14 @@ static void __rcu_offline_cpu(int cpu, struct rcu_state *rsp)
int need_report = 0;
struct rcu_data *rdp = per_cpu_ptr(rsp->rda, cpu);
struct rcu_node *rnp;
+ struct task_struct *t;
+
+ /* Stop the CPU's kthread. */
+ t = per_cpu(rcu_cpu_kthread_task, cpu);
+ if (t != NULL) {
+ per_cpu(rcu_cpu_kthread_task, cpu) = NULL;
+ kthread_stop(t);
+ }
/* Exclude any attempts to start a new grace period. */
raw_spin_lock_irqsave(&rsp->onofflock, flags);
@@ -1082,6 +1137,7 @@ static void __rcu_offline_cpu(int cpu, struct rcu_state *rsp)
raw_spin_unlock_irqrestore(&rnp->lock, flags);
if (need_report & RCU_OFL_TASKS_EXP_GP)
rcu_report_exp_rnp(rsp, rnp);
+ rcu_node_kthread_setaffinity(rnp, -1);
}
/*
@@ -1143,7 +1199,7 @@ static void rcu_do_batch(struct rcu_state *rsp, struct rcu_data *rdp)
next = list->next;
prefetch(next);
debug_rcu_head_unqueue(list);
- list->func(list);
+ __rcu_reclaim(list);
list = next;
if (++count >= rdp->blimit)
break;
@@ -1179,7 +1235,7 @@ static void rcu_do_batch(struct rcu_state *rsp, struct rcu_data *rdp)
/* Re-raise the RCU softirq if there are callbacks remaining. */
if (cpu_has_callbacks_ready_to_invoke(rdp))
- raise_softirq(RCU_SOFTIRQ);
+ invoke_rcu_cpu_kthread();
}
/*
@@ -1225,7 +1281,7 @@ void rcu_check_callbacks(int cpu, int user)
}
rcu_preempt_check_callbacks(cpu);
if (rcu_pending(cpu))
- raise_softirq(RCU_SOFTIRQ);
+ invoke_rcu_cpu_kthread();
}
#ifdef CONFIG_SMP
@@ -1233,6 +1289,8 @@ void rcu_check_callbacks(int cpu, int user)
/*
* Scan the leaf rcu_node structures, processing dyntick state for any that
* have not yet encountered a quiescent state, using the function specified.
+ * Also initiate boosting for any threads blocked on the root rcu_node.
+ *
* The caller must have suppressed start of new grace periods.
*/
static void force_qs_rnp(struct rcu_state *rsp, int (*f)(struct rcu_data *))
@@ -1251,7 +1309,7 @@ static void force_qs_rnp(struct rcu_state *rsp, int (*f)(struct rcu_data *))
return;
}
if (rnp->qsmask == 0) {
- raw_spin_unlock_irqrestore(&rnp->lock, flags);
+ rcu_initiate_boost(rnp, flags); /* releases rnp->lock */
continue;
}
cpu = rnp->grplo;
@@ -1269,6 +1327,11 @@ static void force_qs_rnp(struct rcu_state *rsp, int (*f)(struct rcu_data *))
}
raw_spin_unlock_irqrestore(&rnp->lock, flags);
}
+ rnp = rcu_get_root(rsp);
+ if (rnp->qsmask == 0) {
+ raw_spin_lock_irqsave(&rnp->lock, flags);
+ rcu_initiate_boost(rnp, flags); /* releases rnp->lock. */
+ }
}
/*
@@ -1389,7 +1452,7 @@ __rcu_process_callbacks(struct rcu_state *rsp, struct rcu_data *rdp)
/*
* Do softirq processing for the current CPU.
*/
-static void rcu_process_callbacks(struct softirq_action *unused)
+static void rcu_process_callbacks(void)
{
/*
* Memory references from any prior RCU read-side critical sections
@@ -1414,6 +1477,347 @@ static void rcu_process_callbacks(struct softirq_action *unused)
rcu_needs_cpu_flush();
}
+/*
+ * Wake up the current CPU's kthread. This replaces raise_softirq()
+ * in earlier versions of RCU. Note that because we are running on
+ * the current CPU with interrupts disabled, the rcu_cpu_kthread_task
+ * cannot disappear out from under us.
+ */
+static void invoke_rcu_cpu_kthread(void)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+ __this_cpu_write(rcu_cpu_has_work, 1);
+ if (__this_cpu_read(rcu_cpu_kthread_task) == NULL) {
+ local_irq_restore(flags);
+ return;
+ }
+ wake_up(&__get_cpu_var(rcu_cpu_wq));
+ local_irq_restore(flags);
+}
+
+/*
+ * Wake up the specified per-rcu_node-structure kthread.
+ * Because the per-rcu_node kthreads are immortal, we don't need
+ * to do anything to keep them alive.
+ */
+static void invoke_rcu_node_kthread(struct rcu_node *rnp)
+{
+ struct task_struct *t;
+
+ t = rnp->node_kthread_task;
+ if (t != NULL)
+ wake_up_process(t);
+}
+
+/*
+ * Set the specified CPU's kthread to run RT or not, as specified by
+ * the to_rt argument. The CPU-hotplug locks are held, so the task
+ * is not going away.
+ */
+static void rcu_cpu_kthread_setrt(int cpu, int to_rt)
+{
+ int policy;
+ struct sched_param sp;
+ struct task_struct *t;
+
+ t = per_cpu(rcu_cpu_kthread_task, cpu);
+ if (t == NULL)
+ return;
+ if (to_rt) {
+ policy = SCHED_FIFO;
+ sp.sched_priority = RCU_KTHREAD_PRIO;
+ } else {
+ policy = SCHED_NORMAL;
+ sp.sched_priority = 0;
+ }
+ sched_setscheduler_nocheck(t, policy, &sp);
+}
+
+/*
+ * Timer handler to initiate the waking up of per-CPU kthreads that
+ * have yielded the CPU due to excess numbers of RCU callbacks.
+ * We wake up the per-rcu_node kthread, which in turn will wake up
+ * the booster kthread.
+ */
+static void rcu_cpu_kthread_timer(unsigned long arg)
+{
+ unsigned long flags;
+ struct rcu_data *rdp = per_cpu_ptr(rcu_state->rda, arg);
+ struct rcu_node *rnp = rdp->mynode;
+
+ raw_spin_lock_irqsave(&rnp->lock, flags);
+ rnp->wakemask |= rdp->grpmask;
+ raw_spin_unlock_irqrestore(&rnp->lock, flags);
+ invoke_rcu_node_kthread(rnp);
+}
+
+/*
+ * Drop to non-real-time priority and yield, but only after posting a
+ * timer that will cause us to regain our real-time priority if we
+ * remain preempted. Either way, we restore our real-time priority
+ * before returning.
+ */
+static void rcu_yield(void (*f)(unsigned long), unsigned long arg)
+{
+ struct sched_param sp;
+ struct timer_list yield_timer;
+
+ setup_timer_on_stack(&yield_timer, f, arg);
+ mod_timer(&yield_timer, jiffies + 2);
+ sp.sched_priority = 0;
+ sched_setscheduler_nocheck(current, SCHED_NORMAL, &sp);
+ set_user_nice(current, 19);
+ schedule();
+ sp.sched_priority = RCU_KTHREAD_PRIO;
+ sched_setscheduler_nocheck(current, SCHED_FIFO, &sp);
+ del_timer(&yield_timer);
+}
+
+/*
+ * Handle cases where the rcu_cpu_kthread() ends up on the wrong CPU.
+ * This can happen while the corresponding CPU is either coming online
+ * or going offline. We cannot wait until the CPU is fully online
+ * before starting the kthread, because the various notifier functions
+ * can wait for RCU grace periods. So we park rcu_cpu_kthread() until
+ * the corresponding CPU is online.
+ *
+ * Return 1 if the kthread needs to stop, 0 otherwise.
+ *
+ * Caller must disable bh. This function can momentarily enable it.
+ */
+static int rcu_cpu_kthread_should_stop(int cpu)
+{
+ while (cpu_is_offline(cpu) ||
+ !cpumask_equal(&current->cpus_allowed, cpumask_of(cpu)) ||
+ smp_processor_id() != cpu) {
+ if (kthread_should_stop())
+ return 1;
+ per_cpu(rcu_cpu_kthread_status, cpu) = RCU_KTHREAD_OFFCPU;
+ per_cpu(rcu_cpu_kthread_cpu, cpu) = raw_smp_processor_id();
+ local_bh_enable();
+ schedule_timeout_uninterruptible(1);
+ if (!cpumask_equal(&current->cpus_allowed, cpumask_of(cpu)))
+ set_cpus_allowed_ptr(current, cpumask_of(cpu));
+ local_bh_disable();
+ }
+ per_cpu(rcu_cpu_kthread_cpu, cpu) = cpu;
+ return 0;
+}
+
+/*
+ * Per-CPU kernel thread that invokes RCU callbacks. This replaces the
+ * earlier RCU softirq.
+ */
+static int rcu_cpu_kthread(void *arg)
+{
+ int cpu = (int)(long)arg;
+ unsigned long flags;
+ int spincnt = 0;
+ unsigned int *statusp = &per_cpu(rcu_cpu_kthread_status, cpu);
+ wait_queue_head_t *wqp = &per_cpu(rcu_cpu_wq, cpu);
+ char work;
+ char *workp = &per_cpu(rcu_cpu_has_work, cpu);
+
+ for (;;) {
+ *statusp = RCU_KTHREAD_WAITING;
+ wait_event_interruptible(*wqp,
+ *workp != 0 || kthread_should_stop());
+ local_bh_disable();
+ if (rcu_cpu_kthread_should_stop(cpu)) {
+ local_bh_enable();
+ break;
+ }
+ *statusp = RCU_KTHREAD_RUNNING;
+ per_cpu(rcu_cpu_kthread_loops, cpu)++;
+ local_irq_save(flags);
+ work = *workp;
+ *workp = 0;
+ local_irq_restore(flags);
+ if (work)
+ rcu_process_callbacks();
+ local_bh_enable();
+ if (*workp != 0)
+ spincnt++;
+ else
+ spincnt = 0;
+ if (spincnt > 10) {
+ *statusp = RCU_KTHREAD_YIELDING;
+ rcu_yield(rcu_cpu_kthread_timer, (unsigned long)cpu);
+ spincnt = 0;
+ }
+ }
+ *statusp = RCU_KTHREAD_STOPPED;
+ return 0;
+}
+
+/*
+ * Spawn a per-CPU kthread, setting up affinity and priority.
+ * Because the CPU hotplug lock is held, no other CPU will be attempting
+ * to manipulate rcu_cpu_kthread_task. There might be another CPU
+ * attempting to access it during boot, but the locking in kthread_bind()
+ * will enforce sufficient ordering.
+ */
+static int __cpuinit rcu_spawn_one_cpu_kthread(int cpu)
+{
+ struct sched_param sp;
+ struct task_struct *t;
+
+ if (!rcu_kthreads_spawnable ||
+ per_cpu(rcu_cpu_kthread_task, cpu) != NULL)
+ return 0;
+ t = kthread_create(rcu_cpu_kthread, (void *)(long)cpu, "rcuc%d", cpu);
+ if (IS_ERR(t))
+ return PTR_ERR(t);
+ kthread_bind(t, cpu);
+ per_cpu(rcu_cpu_kthread_cpu, cpu) = cpu;
+ WARN_ON_ONCE(per_cpu(rcu_cpu_kthread_task, cpu) != NULL);
+ per_cpu(rcu_cpu_kthread_task, cpu) = t;
+ wake_up_process(t);
+ sp.sched_priority = RCU_KTHREAD_PRIO;
+ sched_setscheduler_nocheck(t, SCHED_FIFO, &sp);
+ return 0;
+}
+
+/*
+ * Per-rcu_node kthread, which is in charge of waking up the per-CPU
+ * kthreads when needed. We ignore requests to wake up kthreads
+ * for offline CPUs, which is OK because force_quiescent_state()
+ * takes care of this case.
+ */
+static int rcu_node_kthread(void *arg)
+{
+ int cpu;
+ unsigned long flags;
+ unsigned long mask;
+ struct rcu_node *rnp = (struct rcu_node *)arg;
+ struct sched_param sp;
+ struct task_struct *t;
+
+ for (;;) {
+ rnp->node_kthread_status = RCU_KTHREAD_WAITING;
+ wait_event_interruptible(rnp->node_wq, rnp->wakemask != 0);
+ rnp->node_kthread_status = RCU_KTHREAD_RUNNING;
+ raw_spin_lock_irqsave(&rnp->lock, flags);
+ mask = rnp->wakemask;
+ rnp->wakemask = 0;
+ rcu_initiate_boost(rnp, flags); /* releases rnp->lock. */
+ for (cpu = rnp->grplo; cpu <= rnp->grphi; cpu++, mask >>= 1) {
+ if ((mask & 0x1) == 0)
+ continue;
+ preempt_disable();
+ t = per_cpu(rcu_cpu_kthread_task, cpu);
+ if (!cpu_online(cpu) || t == NULL) {
+ preempt_enable();
+ continue;
+ }
+ per_cpu(rcu_cpu_has_work, cpu) = 1;
+ sp.sched_priority = RCU_KTHREAD_PRIO;
+ sched_setscheduler_nocheck(t, SCHED_FIFO, &sp);
+ preempt_enable();
+ }
+ }
+ /* NOTREACHED */
+ rnp->node_kthread_status = RCU_KTHREAD_STOPPED;
+ return 0;
+}
+
+/*
+ * Set the per-rcu_node kthread's affinity to cover all CPUs that are
+ * served by the rcu_node in question. The CPU hotplug lock is still
+ * held, so the value of rnp->qsmaskinit will be stable.
+ *
+ * We don't include outgoingcpu in the affinity set, use -1 if there is
+ * no outgoing CPU. If there are no CPUs left in the affinity set,
+ * this function allows the kthread to execute on any CPU.
+ */
+static void rcu_node_kthread_setaffinity(struct rcu_node *rnp, int outgoingcpu)
+{
+ cpumask_var_t cm;
+ int cpu;
+ unsigned long mask = rnp->qsmaskinit;
+
+ if (rnp->node_kthread_task == NULL)
+ return;
+ if (!alloc_cpumask_var(&cm, GFP_KERNEL))
+ return;
+ cpumask_clear(cm);
+ for (cpu = rnp->grplo; cpu <= rnp->grphi; cpu++, mask >>= 1)
+ if ((mask & 0x1) && cpu != outgoingcpu)
+ cpumask_set_cpu(cpu, cm);
+ if (cpumask_weight(cm) == 0) {
+ cpumask_setall(cm);
+ for (cpu = rnp->grplo; cpu <= rnp->grphi; cpu++)
+ cpumask_clear_cpu(cpu, cm);
+ WARN_ON_ONCE(cpumask_weight(cm) == 0);
+ }
+ set_cpus_allowed_ptr(rnp->node_kthread_task, cm);
+ rcu_boost_kthread_setaffinity(rnp, cm);
+ free_cpumask_var(cm);
+}
+
+/*
+ * Spawn a per-rcu_node kthread, setting priority and affinity.
+ * Called during boot before online/offline can happen, or, if
+ * during runtime, with the main CPU-hotplug locks held. So only
+ * one of these can be executing at a time.
+ */
+static int __cpuinit rcu_spawn_one_node_kthread(struct rcu_state *rsp,
+ struct rcu_node *rnp)
+{
+ unsigned long flags;
+ int rnp_index = rnp - &rsp->node[0];
+ struct sched_param sp;
+ struct task_struct *t;
+
+ if (!rcu_kthreads_spawnable ||
+ rnp->qsmaskinit == 0)
+ return 0;
+ if (rnp->node_kthread_task == NULL) {
+ t = kthread_create(rcu_node_kthread, (void *)rnp,
+ "rcun%d", rnp_index);
+ if (IS_ERR(t))
+ return PTR_ERR(t);
+ raw_spin_lock_irqsave(&rnp->lock, flags);
+ rnp->node_kthread_task = t;
+ raw_spin_unlock_irqrestore(&rnp->lock, flags);
+ wake_up_process(t);
+ sp.sched_priority = 99;
+ sched_setscheduler_nocheck(t, SCHED_FIFO, &sp);
+ }
+ return rcu_spawn_one_boost_kthread(rsp, rnp, rnp_index);
+}
+
+/*
+ * Spawn all kthreads -- called as soon as the scheduler is running.
+ */
+static int __init rcu_spawn_kthreads(void)
+{
+ int cpu;
+ struct rcu_node *rnp;
+
+ rcu_kthreads_spawnable = 1;
+ for_each_possible_cpu(cpu) {
+ init_waitqueue_head(&per_cpu(rcu_cpu_wq, cpu));
+ per_cpu(rcu_cpu_has_work, cpu) = 0;
+ if (cpu_online(cpu))
+ (void)rcu_spawn_one_cpu_kthread(cpu);
+ }
+ rnp = rcu_get_root(rcu_state);
+ init_waitqueue_head(&rnp->node_wq);
+ rcu_init_boost_waitqueue(rnp);
+ (void)rcu_spawn_one_node_kthread(rcu_state, rnp);
+ if (NUM_RCU_NODES > 1)
+ rcu_for_each_leaf_node(rcu_state, rnp) {
+ init_waitqueue_head(&rnp->node_wq);
+ rcu_init_boost_waitqueue(rnp);
+ (void)rcu_spawn_one_node_kthread(rcu_state, rnp);
+ }
+ return 0;
+}
+early_initcall(rcu_spawn_kthreads);
+
static void
__call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu),
struct rcu_state *rsp)
@@ -1439,6 +1843,13 @@ __call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu),
/* Add the callback to our list. */
*rdp->nxttail[RCU_NEXT_TAIL] = head;
rdp->nxttail[RCU_NEXT_TAIL] = &head->next;
+ rdp->qlen++;
+
+ /* If interrupts were disabled, don't dive into RCU core. */
+ if (irqs_disabled_flags(flags)) {
+ local_irq_restore(flags);
+ return;
+ }
/*
* Force the grace period if too many callbacks or too long waiting.
@@ -1447,7 +1858,7 @@ __call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu),
* invoking force_quiescent_state() if the newly enqueued callback
* is the only one waiting for a grace period to complete.
*/
- if (unlikely(++rdp->qlen > rdp->qlen_last_fqs_check + qhimark)) {
+ if (unlikely(rdp->qlen > rdp->qlen_last_fqs_check + qhimark)) {
/* Are we ignoring a completed grace period? */
rcu_process_gp_end(rsp, rdp);
@@ -1583,7 +1994,7 @@ static int __rcu_pending(struct rcu_state *rsp, struct rcu_data *rdp)
* or RCU-bh, force a local reschedule.
*/
rdp->n_rp_qs_pending++;
- if (!rdp->preemptable &&
+ if (!rdp->preemptible &&
ULONG_CMP_LT(ACCESS_ONCE(rsp->jiffies_force_qs) - 1,
jiffies))
set_need_resched();
@@ -1760,7 +2171,7 @@ rcu_boot_init_percpu_data(int cpu, struct rcu_state *rsp)
* that this CPU cannot possibly have any RCU callbacks in flight yet.
*/
static void __cpuinit
-rcu_init_percpu_data(int cpu, struct rcu_state *rsp, int preemptable)
+rcu_init_percpu_data(int cpu, struct rcu_state *rsp, int preemptible)
{
unsigned long flags;
unsigned long mask;
@@ -1772,7 +2183,7 @@ rcu_init_percpu_data(int cpu, struct rcu_state *rsp, int preemptable)
rdp->passed_quiesc = 0; /* We could be racing with new GP, */
rdp->qs_pending = 1; /* so set up to respond to current GP. */
rdp->beenonline = 1; /* We have now been online. */
- rdp->preemptable = preemptable;
+ rdp->preemptible = preemptible;
rdp->qlen_last_fqs_check = 0;
rdp->n_force_qs_snap = rsp->n_force_qs;
rdp->blimit = blimit;
@@ -1813,6 +2224,19 @@ static void __cpuinit rcu_online_cpu(int cpu)
rcu_preempt_init_percpu_data(cpu);
}
+static void __cpuinit rcu_online_kthreads(int cpu)
+{
+ struct rcu_data *rdp = per_cpu_ptr(rcu_state->rda, cpu);
+ struct rcu_node *rnp = rdp->mynode;
+
+ /* Fire up the incoming CPU's kthread and leaf rcu_node kthread. */
+ if (rcu_kthreads_spawnable) {
+ (void)rcu_spawn_one_cpu_kthread(cpu);
+ if (rnp->node_kthread_task == NULL)
+ (void)rcu_spawn_one_node_kthread(rcu_state, rnp);
+ }
+}
+
/*
* Handle CPU online/offline notification events.
*/
@@ -1820,11 +2244,23 @@ static int __cpuinit rcu_cpu_notify(struct notifier_block *self,
unsigned long action, void *hcpu)
{
long cpu = (long)hcpu;
+ struct rcu_data *rdp = per_cpu_ptr(rcu_state->rda, cpu);
+ struct rcu_node *rnp = rdp->mynode;
switch (action) {
case CPU_UP_PREPARE:
case CPU_UP_PREPARE_FROZEN:
rcu_online_cpu(cpu);
+ rcu_online_kthreads(cpu);
+ break;
+ case CPU_ONLINE:
+ case CPU_DOWN_FAILED:
+ rcu_node_kthread_setaffinity(rnp, -1);
+ rcu_cpu_kthread_setrt(cpu, 1);
+ break;
+ case CPU_DOWN_PREPARE:
+ rcu_node_kthread_setaffinity(rnp, cpu);
+ rcu_cpu_kthread_setrt(cpu, 0);
break;
case CPU_DYING:
case CPU_DYING_FROZEN:
@@ -1943,10 +2379,7 @@ static void __init rcu_init_one(struct rcu_state *rsp,
j / rsp->levelspread[i - 1];
}
rnp->level = i;
- INIT_LIST_HEAD(&rnp->blocked_tasks[0]);
- INIT_LIST_HEAD(&rnp->blocked_tasks[1]);
- INIT_LIST_HEAD(&rnp->blocked_tasks[2]);
- INIT_LIST_HEAD(&rnp->blocked_tasks[3]);
+ INIT_LIST_HEAD(&rnp->blkd_tasks);
}
}
@@ -1968,7 +2401,6 @@ void __init rcu_init(void)
rcu_init_one(&rcu_sched_state, &rcu_sched_data);
rcu_init_one(&rcu_bh_state, &rcu_bh_data);
__rcu_init_preempt();
- open_softirq(RCU_SOFTIRQ, rcu_process_callbacks);
/*
* We don't need protection against CPU-hotplug here because
diff --git a/kernel/rcutree.h b/kernel/rcutree.h
index e8f057e44e3..257664815d5 100644
--- a/kernel/rcutree.h
+++ b/kernel/rcutree.h
@@ -91,6 +91,14 @@ struct rcu_dynticks {
/* remains even for nmi from irq handler. */
};
+/* RCU's kthread states for tracing. */
+#define RCU_KTHREAD_STOPPED 0
+#define RCU_KTHREAD_RUNNING 1
+#define RCU_KTHREAD_WAITING 2
+#define RCU_KTHREAD_OFFCPU 3
+#define RCU_KTHREAD_YIELDING 4
+#define RCU_KTHREAD_MAX 4
+
/*
* Definition for node within the RCU grace-period-detection hierarchy.
*/
@@ -109,10 +117,11 @@ struct rcu_node {
/* an rcu_data structure, otherwise, each */
/* bit corresponds to a child rcu_node */
/* structure. */
- unsigned long expmask; /* Groups that have ->blocked_tasks[] */
+ unsigned long expmask; /* Groups that have ->blkd_tasks */
/* elements that need to drain to allow the */
/* current expedited grace period to */
/* complete (only for TREE_PREEMPT_RCU). */
+ unsigned long wakemask; /* CPUs whose kthread needs to be awakened. */
unsigned long qsmaskinit;
/* Per-GP initial value for qsmask & expmask. */
unsigned long grpmask; /* Mask to apply to parent qsmask. */
@@ -122,11 +131,68 @@ struct rcu_node {
u8 grpnum; /* CPU/group number for next level up. */
u8 level; /* root is at level 0. */
struct rcu_node *parent;
- struct list_head blocked_tasks[4];
- /* Tasks blocked in RCU read-side critsect. */
- /* Grace period number (->gpnum) x blocked */
- /* by tasks on the (x & 0x1) element of the */
- /* blocked_tasks[] array. */
+ struct list_head blkd_tasks;
+ /* Tasks blocked in RCU read-side critical */
+ /* section. Tasks are placed at the head */
+ /* of this list and age towards the tail. */
+ struct list_head *gp_tasks;
+ /* Pointer to the first task blocking the */
+ /* current grace period, or NULL if there */
+ /* is no such task. */
+ struct list_head *exp_tasks;
+ /* Pointer to the first task blocking the */
+ /* current expedited grace period, or NULL */
+ /* if there is no such task. If there */
+ /* is no current expedited grace period, */
+ /* then there can cannot be any such task. */
+#ifdef CONFIG_RCU_BOOST
+ struct list_head *boost_tasks;
+ /* Pointer to first task that needs to be */
+ /* priority boosted, or NULL if no priority */
+ /* boosting is needed for this rcu_node */
+ /* structure. If there are no tasks */
+ /* queued on this rcu_node structure that */
+ /* are blocking the current grace period, */
+ /* there can be no such task. */
+ unsigned long boost_time;
+ /* When to start boosting (jiffies). */
+ struct task_struct *boost_kthread_task;
+ /* kthread that takes care of priority */
+ /* boosting for this rcu_node structure. */
+ wait_queue_head_t boost_wq;
+ /* Wait queue on which to park the boost */
+ /* kthread. */
+ unsigned int boost_kthread_status;
+ /* State of boost_kthread_task for tracing. */
+ unsigned long n_tasks_boosted;
+ /* Total number of tasks boosted. */
+ unsigned long n_exp_boosts;
+ /* Number of tasks boosted for expedited GP. */
+ unsigned long n_normal_boosts;
+ /* Number of tasks boosted for normal GP. */
+ unsigned long n_balk_blkd_tasks;
+ /* Refused to boost: no blocked tasks. */
+ unsigned long n_balk_exp_gp_tasks;
+ /* Refused to boost: nothing blocking GP. */
+ unsigned long n_balk_boost_tasks;
+ /* Refused to boost: already boosting. */
+ unsigned long n_balk_notblocked;
+ /* Refused to boost: RCU RS CS still running. */
+ unsigned long n_balk_notyet;
+ /* Refused to boost: not yet time. */
+ unsigned long n_balk_nos;
+ /* Refused to boost: not sure why, though. */
+ /* This can happen due to race conditions. */
+#endif /* #ifdef CONFIG_RCU_BOOST */
+ struct task_struct *node_kthread_task;
+ /* kthread that takes care of this rcu_node */
+ /* structure, for example, awakening the */
+ /* per-CPU kthreads as needed. */
+ wait_queue_head_t node_wq;
+ /* Wait queue on which to park the per-node */
+ /* kthread. */
+ unsigned int node_kthread_status;
+ /* State of node_kthread_task for tracing. */
} ____cacheline_internodealigned_in_smp;
/*
@@ -175,7 +241,7 @@ struct rcu_data {
bool passed_quiesc; /* User-mode/idle loop etc. */
bool qs_pending; /* Core waits for quiesc state. */
bool beenonline; /* CPU online at least once. */
- bool preemptable; /* Preemptable RCU? */
+ bool preemptible; /* Preemptible RCU? */
struct rcu_node *mynode; /* This CPU's leaf of hierarchy */
unsigned long grpmask; /* Mask to apply to leaf qsmask. */
@@ -254,7 +320,6 @@ struct rcu_data {
#endif /* #else #ifdef CONFIG_NO_HZ */
#define RCU_JIFFIES_TILL_FORCE_QS 3 /* for rsp->jiffies_force_qs */
-#ifdef CONFIG_RCU_CPU_STALL_DETECTOR
#ifdef CONFIG_PROVE_RCU
#define RCU_STALL_DELAY_DELTA (5 * HZ)
@@ -272,13 +337,6 @@ struct rcu_data {
/* scheduling clock irq */
/* before ratting on them. */
-#ifdef CONFIG_RCU_CPU_STALL_DETECTOR_RUNNABLE
-#define RCU_CPU_STALL_SUPPRESS_INIT 0
-#else
-#define RCU_CPU_STALL_SUPPRESS_INIT 1
-#endif
-
-#endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
/*
* RCU global state, including node hierarchy. This hierarchy is
@@ -325,12 +383,12 @@ struct rcu_state {
/* due to lock unavailable. */
unsigned long n_force_qs_ngp; /* Number of calls leaving */
/* due to no GP active. */
-#ifdef CONFIG_RCU_CPU_STALL_DETECTOR
unsigned long gp_start; /* Time at which GP started, */
/* but in jiffies. */
unsigned long jiffies_stall; /* Time at which to check */
/* for CPU stalls. */
-#endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
+ unsigned long gp_max; /* Maximum GP duration in */
+ /* jiffies. */
char *name; /* Name of structure. */
};
@@ -361,16 +419,14 @@ DECLARE_PER_CPU(struct rcu_data, rcu_preempt_data);
static void rcu_bootup_announce(void);
long rcu_batches_completed(void);
static void rcu_preempt_note_context_switch(int cpu);
-static int rcu_preempted_readers(struct rcu_node *rnp);
+static int rcu_preempt_blocked_readers_cgp(struct rcu_node *rnp);
#ifdef CONFIG_HOTPLUG_CPU
static void rcu_report_unblock_qs_rnp(struct rcu_node *rnp,
unsigned long flags);
#endif /* #ifdef CONFIG_HOTPLUG_CPU */
-#ifdef CONFIG_RCU_CPU_STALL_DETECTOR
static void rcu_print_detail_task_stall(struct rcu_state *rsp);
static void rcu_print_task_stall(struct rcu_node *rnp);
static void rcu_preempt_stall_reset(void);
-#endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp);
#ifdef CONFIG_HOTPLUG_CPU
static int rcu_preempt_offline_tasks(struct rcu_state *rsp,
@@ -390,5 +446,13 @@ static void __cpuinit rcu_preempt_init_percpu_data(int cpu);
static void rcu_preempt_send_cbs_to_online(void);
static void __init __rcu_init_preempt(void);
static void rcu_needs_cpu_flush(void);
+static void __init rcu_init_boost_waitqueue(struct rcu_node *rnp);
+static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags);
+static void rcu_boost_kthread_setaffinity(struct rcu_node *rnp,
+ cpumask_var_t cm);
+static void rcu_preempt_boost_start_gp(struct rcu_node *rnp);
+static int __cpuinit rcu_spawn_one_boost_kthread(struct rcu_state *rsp,
+ struct rcu_node *rnp,
+ int rnp_index);
#endif /* #ifndef RCU_TREE_NONCORE */
diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h
index a3638710dc6..3f6559a5f5c 100644
--- a/kernel/rcutree_plugin.h
+++ b/kernel/rcutree_plugin.h
@@ -1,7 +1,7 @@
/*
* Read-Copy Update mechanism for mutual exclusion (tree-based version)
* Internal non-public definitions that provide either classic
- * or preemptable semantics.
+ * or preemptible semantics.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@@ -54,10 +54,6 @@ static void __init rcu_bootup_announce_oddness(void)
#ifdef CONFIG_RCU_TORTURE_TEST_RUNNABLE
printk(KERN_INFO "\tRCU torture testing starts during boot.\n");
#endif
-#ifndef CONFIG_RCU_CPU_STALL_DETECTOR
- printk(KERN_INFO
- "\tRCU-based detection of stalled CPUs is disabled.\n");
-#endif
#if defined(CONFIG_TREE_PREEMPT_RCU) && !defined(CONFIG_RCU_CPU_STALL_VERBOSE)
printk(KERN_INFO "\tVerbose stalled-CPUs detection is disabled.\n");
#endif
@@ -70,6 +66,7 @@ static void __init rcu_bootup_announce_oddness(void)
struct rcu_state rcu_preempt_state = RCU_STATE_INITIALIZER(rcu_preempt_state);
DEFINE_PER_CPU(struct rcu_data, rcu_preempt_data);
+static struct rcu_state *rcu_state = &rcu_preempt_state;
static int rcu_preempted_readers_exp(struct rcu_node *rnp);
@@ -78,7 +75,7 @@ static int rcu_preempted_readers_exp(struct rcu_node *rnp);
*/
static void __init rcu_bootup_announce(void)
{
- printk(KERN_INFO "Preemptable hierarchical RCU implementation.\n");
+ printk(KERN_INFO "Preemptible hierarchical RCU implementation.\n");
rcu_bootup_announce_oddness();
}
@@ -111,7 +108,7 @@ void rcu_force_quiescent_state(void)
EXPORT_SYMBOL_GPL(rcu_force_quiescent_state);
/*
- * Record a preemptable-RCU quiescent state for the specified CPU. Note
+ * Record a preemptible-RCU quiescent state for the specified CPU. Note
* that this just means that the task currently running on the CPU is
* not in a quiescent state. There might be any number of tasks blocked
* while in an RCU read-side critical section.
@@ -134,12 +131,12 @@ static void rcu_preempt_qs(int cpu)
* We have entered the scheduler, and the current task might soon be
* context-switched away from. If this task is in an RCU read-side
* critical section, we will no longer be able to rely on the CPU to
- * record that fact, so we enqueue the task on the appropriate entry
- * of the blocked_tasks[] array. The task will dequeue itself when
- * it exits the outermost enclosing RCU read-side critical section.
- * Therefore, the current grace period cannot be permitted to complete
- * until the blocked_tasks[] entry indexed by the low-order bit of
- * rnp->gpnum empties.
+ * record that fact, so we enqueue the task on the blkd_tasks list.
+ * The task will dequeue itself when it exits the outermost enclosing
+ * RCU read-side critical section. Therefore, the current grace period
+ * cannot be permitted to complete until the blkd_tasks list entries
+ * predating the current grace period drain, in other words, until
+ * rnp->gp_tasks becomes NULL.
*
* Caller must disable preemption.
*/
@@ -147,7 +144,6 @@ static void rcu_preempt_note_context_switch(int cpu)
{
struct task_struct *t = current;
unsigned long flags;
- int phase;
struct rcu_data *rdp;
struct rcu_node *rnp;
@@ -169,15 +165,30 @@ static void rcu_preempt_note_context_switch(int cpu)
* (i.e., this CPU has not yet passed through a quiescent
* state for the current grace period), then as long
* as that task remains queued, the current grace period
- * cannot end.
+ * cannot end. Note that there is some uncertainty as
+ * to exactly when the current grace period started.
+ * We take a conservative approach, which can result
+ * in unnecessarily waiting on tasks that started very
+ * slightly after the current grace period began. C'est
+ * la vie!!!
*
* But first, note that the current CPU must still be
* on line!
*/
WARN_ON_ONCE((rdp->grpmask & rnp->qsmaskinit) == 0);
WARN_ON_ONCE(!list_empty(&t->rcu_node_entry));
- phase = (rnp->gpnum + !(rnp->qsmask & rdp->grpmask)) & 0x1;
- list_add(&t->rcu_node_entry, &rnp->blocked_tasks[phase]);
+ if ((rnp->qsmask & rdp->grpmask) && rnp->gp_tasks != NULL) {
+ list_add(&t->rcu_node_entry, rnp->gp_tasks->prev);
+ rnp->gp_tasks = &t->rcu_node_entry;
+#ifdef CONFIG_RCU_BOOST
+ if (rnp->boost_tasks != NULL)
+ rnp->boost_tasks = rnp->gp_tasks;
+#endif /* #ifdef CONFIG_RCU_BOOST */
+ } else {
+ list_add(&t->rcu_node_entry, &rnp->blkd_tasks);
+ if (rnp->qsmask & rdp->grpmask)
+ rnp->gp_tasks = &t->rcu_node_entry;
+ }
raw_spin_unlock_irqrestore(&rnp->lock, flags);
}
@@ -196,7 +207,7 @@ static void rcu_preempt_note_context_switch(int cpu)
}
/*
- * Tree-preemptable RCU implementation for rcu_read_lock().
+ * Tree-preemptible RCU implementation for rcu_read_lock().
* Just increment ->rcu_read_lock_nesting, shared state will be updated
* if we block.
*/
@@ -212,12 +223,9 @@ EXPORT_SYMBOL_GPL(__rcu_read_lock);
* for the specified rcu_node structure. If the caller needs a reliable
* answer, it must hold the rcu_node's ->lock.
*/
-static int rcu_preempted_readers(struct rcu_node *rnp)
+static int rcu_preempt_blocked_readers_cgp(struct rcu_node *rnp)
{
- int phase = rnp->gpnum & 0x1;
-
- return !list_empty(&rnp->blocked_tasks[phase]) ||
- !list_empty(&rnp->blocked_tasks[phase + 2]);
+ return rnp->gp_tasks != NULL;
}
/*
@@ -233,7 +241,7 @@ static void rcu_report_unblock_qs_rnp(struct rcu_node *rnp, unsigned long flags)
unsigned long mask;
struct rcu_node *rnp_p;
- if (rnp->qsmask != 0 || rcu_preempted_readers(rnp)) {
+ if (rnp->qsmask != 0 || rcu_preempt_blocked_readers_cgp(rnp)) {
raw_spin_unlock_irqrestore(&rnp->lock, flags);
return; /* Still need more quiescent states! */
}
@@ -257,6 +265,21 @@ static void rcu_report_unblock_qs_rnp(struct rcu_node *rnp, unsigned long flags)
}
/*
+ * Advance a ->blkd_tasks-list pointer to the next entry, instead
+ * returning NULL if at the end of the list.
+ */
+static struct list_head *rcu_next_node_entry(struct task_struct *t,
+ struct rcu_node *rnp)
+{
+ struct list_head *np;
+
+ np = t->rcu_node_entry.next;
+ if (np == &rnp->blkd_tasks)
+ np = NULL;
+ return np;
+}
+
+/*
* Handle special cases during rcu_read_unlock(), such as needing to
* notify RCU core processing or task having blocked during the RCU
* read-side critical section.
@@ -266,6 +289,7 @@ static void rcu_read_unlock_special(struct task_struct *t)
int empty;
int empty_exp;
unsigned long flags;
+ struct list_head *np;
struct rcu_node *rnp;
int special;
@@ -306,10 +330,19 @@ static void rcu_read_unlock_special(struct task_struct *t)
break;
raw_spin_unlock(&rnp->lock); /* irqs remain disabled. */
}
- empty = !rcu_preempted_readers(rnp);
+ empty = !rcu_preempt_blocked_readers_cgp(rnp);
empty_exp = !rcu_preempted_readers_exp(rnp);
smp_mb(); /* ensure expedited fastpath sees end of RCU c-s. */
+ np = rcu_next_node_entry(t, rnp);
list_del_init(&t->rcu_node_entry);
+ if (&t->rcu_node_entry == rnp->gp_tasks)
+ rnp->gp_tasks = np;
+ if (&t->rcu_node_entry == rnp->exp_tasks)
+ rnp->exp_tasks = np;
+#ifdef CONFIG_RCU_BOOST
+ if (&t->rcu_node_entry == rnp->boost_tasks)
+ rnp->boost_tasks = np;
+#endif /* #ifdef CONFIG_RCU_BOOST */
t->rcu_blocked_node = NULL;
/*
@@ -322,6 +355,15 @@ static void rcu_read_unlock_special(struct task_struct *t)
else
rcu_report_unblock_qs_rnp(rnp, flags);
+#ifdef CONFIG_RCU_BOOST
+ /* Unboost if we were boosted. */
+ if (special & RCU_READ_UNLOCK_BOOSTED) {
+ t->rcu_read_unlock_special &= ~RCU_READ_UNLOCK_BOOSTED;
+ rt_mutex_unlock(t->rcu_boost_mutex);
+ t->rcu_boost_mutex = NULL;
+ }
+#endif /* #ifdef CONFIG_RCU_BOOST */
+
/*
* If this was the last task on the expedited lists,
* then we need to report up the rcu_node hierarchy.
@@ -334,7 +376,7 @@ static void rcu_read_unlock_special(struct task_struct *t)
}
/*
- * Tree-preemptable RCU implementation for rcu_read_unlock().
+ * Tree-preemptible RCU implementation for rcu_read_unlock().
* Decrement ->rcu_read_lock_nesting. If the result is zero (outermost
* rcu_read_unlock()) and ->rcu_read_unlock_special is non-zero, then
* invoke rcu_read_unlock_special() to clean up after a context switch
@@ -356,8 +398,6 @@ void __rcu_read_unlock(void)
}
EXPORT_SYMBOL_GPL(__rcu_read_unlock);
-#ifdef CONFIG_RCU_CPU_STALL_DETECTOR
-
#ifdef CONFIG_RCU_CPU_STALL_VERBOSE
/*
@@ -367,18 +407,16 @@ EXPORT_SYMBOL_GPL(__rcu_read_unlock);
static void rcu_print_detail_task_stall_rnp(struct rcu_node *rnp)
{
unsigned long flags;
- struct list_head *lp;
- int phase;
struct task_struct *t;
- if (rcu_preempted_readers(rnp)) {
- raw_spin_lock_irqsave(&rnp->lock, flags);
- phase = rnp->gpnum & 0x1;
- lp = &rnp->blocked_tasks[phase];
- list_for_each_entry(t, lp, rcu_node_entry)
- sched_show_task(t);
- raw_spin_unlock_irqrestore(&rnp->lock, flags);
- }
+ if (!rcu_preempt_blocked_readers_cgp(rnp))
+ return;
+ raw_spin_lock_irqsave(&rnp->lock, flags);
+ t = list_entry(rnp->gp_tasks,
+ struct task_struct, rcu_node_entry);
+ list_for_each_entry_continue(t, &rnp->blkd_tasks, rcu_node_entry)
+ sched_show_task(t);
+ raw_spin_unlock_irqrestore(&rnp->lock, flags);
}
/*
@@ -408,16 +446,14 @@ static void rcu_print_detail_task_stall(struct rcu_state *rsp)
*/
static void rcu_print_task_stall(struct rcu_node *rnp)
{
- struct list_head *lp;
- int phase;
struct task_struct *t;
- if (rcu_preempted_readers(rnp)) {
- phase = rnp->gpnum & 0x1;
- lp = &rnp->blocked_tasks[phase];
- list_for_each_entry(t, lp, rcu_node_entry)
- printk(" P%d", t->pid);
- }
+ if (!rcu_preempt_blocked_readers_cgp(rnp))
+ return;
+ t = list_entry(rnp->gp_tasks,
+ struct task_struct, rcu_node_entry);
+ list_for_each_entry_continue(t, &rnp->blkd_tasks, rcu_node_entry)
+ printk(" P%d", t->pid);
}
/*
@@ -430,18 +466,21 @@ static void rcu_preempt_stall_reset(void)
rcu_preempt_state.jiffies_stall = jiffies + ULONG_MAX / 2;
}
-#endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
-
/*
* Check that the list of blocked tasks for the newly completed grace
* period is in fact empty. It is a serious bug to complete a grace
* period that still has RCU readers blocked! This function must be
* invoked -before- updating this rnp's ->gpnum, and the rnp's ->lock
* must be held by the caller.
+ *
+ * Also, if there are blocked tasks on the list, they automatically
+ * block the newly created grace period, so set up ->gp_tasks accordingly.
*/
static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp)
{
- WARN_ON_ONCE(rcu_preempted_readers(rnp));
+ WARN_ON_ONCE(rcu_preempt_blocked_readers_cgp(rnp));
+ if (!list_empty(&rnp->blkd_tasks))
+ rnp->gp_tasks = rnp->blkd_tasks.next;
WARN_ON_ONCE(rnp->qsmask);
}
@@ -465,50 +504,68 @@ static int rcu_preempt_offline_tasks(struct rcu_state *rsp,
struct rcu_node *rnp,
struct rcu_data *rdp)
{
- int i;
struct list_head *lp;
struct list_head *lp_root;
int retval = 0;
struct rcu_node *rnp_root = rcu_get_root(rsp);
- struct task_struct *tp;
+ struct task_struct *t;
if (rnp == rnp_root) {
WARN_ONCE(1, "Last CPU thought to be offlined?");
return 0; /* Shouldn't happen: at least one CPU online. */
}
- WARN_ON_ONCE(rnp != rdp->mynode &&
- (!list_empty(&rnp->blocked_tasks[0]) ||
- !list_empty(&rnp->blocked_tasks[1]) ||
- !list_empty(&rnp->blocked_tasks[2]) ||
- !list_empty(&rnp->blocked_tasks[3])));
+
+ /* If we are on an internal node, complain bitterly. */
+ WARN_ON_ONCE(rnp != rdp->mynode);
/*
- * Move tasks up to root rcu_node. Rely on the fact that the
- * root rcu_node can be at most one ahead of the rest of the
- * rcu_nodes in terms of gp_num value. This fact allows us to
- * move the blocked_tasks[] array directly, element by element.
+ * Move tasks up to root rcu_node. Don't try to get fancy for
+ * this corner-case operation -- just put this node's tasks
+ * at the head of the root node's list, and update the root node's
+ * ->gp_tasks and ->exp_tasks pointers to those of this node's,
+ * if non-NULL. This might result in waiting for more tasks than
+ * absolutely necessary, but this is a good performance/complexity
+ * tradeoff.
*/
- if (rcu_preempted_readers(rnp))
+ if (rcu_preempt_blocked_readers_cgp(rnp))
retval |= RCU_OFL_TASKS_NORM_GP;
if (rcu_preempted_readers_exp(rnp))
retval |= RCU_OFL_TASKS_EXP_GP;
- for (i = 0; i < 4; i++) {
- lp = &rnp->blocked_tasks[i];
- lp_root = &rnp_root->blocked_tasks[i];
- while (!list_empty(lp)) {
- tp = list_entry(lp->next, typeof(*tp), rcu_node_entry);
- raw_spin_lock(&rnp_root->lock); /* irqs already disabled */
- list_del(&tp->rcu_node_entry);
- tp->rcu_blocked_node = rnp_root;
- list_add(&tp->rcu_node_entry, lp_root);
- raw_spin_unlock(&rnp_root->lock); /* irqs remain disabled */
- }
+ lp = &rnp->blkd_tasks;
+ lp_root = &rnp_root->blkd_tasks;
+ while (!list_empty(lp)) {
+ t = list_entry(lp->next, typeof(*t), rcu_node_entry);
+ raw_spin_lock(&rnp_root->lock); /* irqs already disabled */
+ list_del(&t->rcu_node_entry);
+ t->rcu_blocked_node = rnp_root;
+ list_add(&t->rcu_node_entry, lp_root);
+ if (&t->rcu_node_entry == rnp->gp_tasks)
+ rnp_root->gp_tasks = rnp->gp_tasks;
+ if (&t->rcu_node_entry == rnp->exp_tasks)
+ rnp_root->exp_tasks = rnp->exp_tasks;
+#ifdef CONFIG_RCU_BOOST
+ if (&t->rcu_node_entry == rnp->boost_tasks)
+ rnp_root->boost_tasks = rnp->boost_tasks;
+#endif /* #ifdef CONFIG_RCU_BOOST */
+ raw_spin_unlock(&rnp_root->lock); /* irqs still disabled */
}
+
+#ifdef CONFIG_RCU_BOOST
+ /* In case root is being boosted and leaf is not. */
+ raw_spin_lock(&rnp_root->lock); /* irqs already disabled */
+ if (rnp_root->boost_tasks != NULL &&
+ rnp_root->boost_tasks != rnp_root->gp_tasks)
+ rnp_root->boost_tasks = rnp_root->gp_tasks;
+ raw_spin_unlock(&rnp_root->lock); /* irqs still disabled */
+#endif /* #ifdef CONFIG_RCU_BOOST */
+
+ rnp->gp_tasks = NULL;
+ rnp->exp_tasks = NULL;
return retval;
}
/*
- * Do CPU-offline processing for preemptable RCU.
+ * Do CPU-offline processing for preemptible RCU.
*/
static void rcu_preempt_offline_cpu(int cpu)
{
@@ -537,7 +594,7 @@ static void rcu_preempt_check_callbacks(int cpu)
}
/*
- * Process callbacks for preemptable RCU.
+ * Process callbacks for preemptible RCU.
*/
static void rcu_preempt_process_callbacks(void)
{
@@ -546,7 +603,7 @@ static void rcu_preempt_process_callbacks(void)
}
/*
- * Queue a preemptable-RCU callback for invocation after a grace period.
+ * Queue a preemptible-RCU callback for invocation after a grace period.
*/
void call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu))
{
@@ -594,8 +651,7 @@ static DEFINE_MUTEX(sync_rcu_preempt_exp_mutex);
*/
static int rcu_preempted_readers_exp(struct rcu_node *rnp)
{
- return !list_empty(&rnp->blocked_tasks[2]) ||
- !list_empty(&rnp->blocked_tasks[3]);
+ return rnp->exp_tasks != NULL;
}
/*
@@ -655,13 +711,17 @@ static void rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp)
static void
sync_rcu_preempt_exp_init(struct rcu_state *rsp, struct rcu_node *rnp)
{
- int must_wait;
+ unsigned long flags;
+ int must_wait = 0;
- raw_spin_lock(&rnp->lock); /* irqs already disabled */
- list_splice_init(&rnp->blocked_tasks[0], &rnp->blocked_tasks[2]);
- list_splice_init(&rnp->blocked_tasks[1], &rnp->blocked_tasks[3]);
- must_wait = rcu_preempted_readers_exp(rnp);
- raw_spin_unlock(&rnp->lock); /* irqs remain disabled */
+ raw_spin_lock_irqsave(&rnp->lock, flags);
+ if (list_empty(&rnp->blkd_tasks))
+ raw_spin_unlock_irqrestore(&rnp->lock, flags);
+ else {
+ rnp->exp_tasks = rnp->blkd_tasks.next;
+ rcu_initiate_boost(rnp, flags); /* releases rnp->lock */
+ must_wait = 1;
+ }
if (!must_wait)
rcu_report_exp_rnp(rsp, rnp);
}
@@ -669,9 +729,7 @@ sync_rcu_preempt_exp_init(struct rcu_state *rsp, struct rcu_node *rnp)
/*
* Wait for an rcu-preempt grace period, but expedite it. The basic idea
* is to invoke synchronize_sched_expedited() to push all the tasks to
- * the ->blocked_tasks[] lists, move all entries from the first set of
- * ->blocked_tasks[] lists to the second set, and finally wait for this
- * second set to drain.
+ * the ->blkd_tasks lists and wait for this list to drain.
*/
void synchronize_rcu_expedited(void)
{
@@ -703,7 +761,7 @@ void synchronize_rcu_expedited(void)
if ((ACCESS_ONCE(sync_rcu_preempt_exp_count) - snap) > 0)
goto unlock_mb_ret; /* Others did our work for us. */
- /* force all RCU readers onto blocked_tasks[]. */
+ /* force all RCU readers onto ->blkd_tasks lists. */
synchronize_sched_expedited();
raw_spin_lock_irqsave(&rsp->onofflock, flags);
@@ -715,7 +773,7 @@ void synchronize_rcu_expedited(void)
raw_spin_unlock(&rnp->lock); /* irqs remain disabled. */
}
- /* Snapshot current state of ->blocked_tasks[] lists. */
+ /* Snapshot current state of ->blkd_tasks lists. */
rcu_for_each_leaf_node(rsp, rnp)
sync_rcu_preempt_exp_init(rsp, rnp);
if (NUM_RCU_NODES > 1)
@@ -723,7 +781,7 @@ void synchronize_rcu_expedited(void)
raw_spin_unlock_irqrestore(&rsp->onofflock, flags);
- /* Wait for snapshotted ->blocked_tasks[] lists to drain. */
+ /* Wait for snapshotted ->blkd_tasks lists to drain. */
rnp = rcu_get_root(rsp);
wait_event(sync_rcu_preempt_exp_wq,
sync_rcu_preempt_exp_done(rnp));
@@ -739,7 +797,7 @@ mb_ret:
EXPORT_SYMBOL_GPL(synchronize_rcu_expedited);
/*
- * Check to see if there is any immediate preemptable-RCU-related work
+ * Check to see if there is any immediate preemptible-RCU-related work
* to be done.
*/
static int rcu_preempt_pending(int cpu)
@@ -749,7 +807,7 @@ static int rcu_preempt_pending(int cpu)
}
/*
- * Does preemptable RCU need the CPU to stay out of dynticks mode?
+ * Does preemptible RCU need the CPU to stay out of dynticks mode?
*/
static int rcu_preempt_needs_cpu(int cpu)
{
@@ -766,7 +824,7 @@ void rcu_barrier(void)
EXPORT_SYMBOL_GPL(rcu_barrier);
/*
- * Initialize preemptable RCU's per-CPU data.
+ * Initialize preemptible RCU's per-CPU data.
*/
static void __cpuinit rcu_preempt_init_percpu_data(int cpu)
{
@@ -774,7 +832,7 @@ static void __cpuinit rcu_preempt_init_percpu_data(int cpu)
}
/*
- * Move preemptable RCU's callbacks from dying CPU to other online CPU.
+ * Move preemptible RCU's callbacks from dying CPU to other online CPU.
*/
static void rcu_preempt_send_cbs_to_online(void)
{
@@ -782,7 +840,7 @@ static void rcu_preempt_send_cbs_to_online(void)
}
/*
- * Initialize preemptable RCU's state structures.
+ * Initialize preemptible RCU's state structures.
*/
static void __init __rcu_init_preempt(void)
{
@@ -790,7 +848,7 @@ static void __init __rcu_init_preempt(void)
}
/*
- * Check for a task exiting while in a preemptable-RCU read-side
+ * Check for a task exiting while in a preemptible-RCU read-side
* critical section, clean up if so. No need to issue warnings,
* as debug_check_no_locks_held() already does this if lockdep
* is enabled.
@@ -802,11 +860,13 @@ void exit_rcu(void)
if (t->rcu_read_lock_nesting == 0)
return;
t->rcu_read_lock_nesting = 1;
- rcu_read_unlock();
+ __rcu_read_unlock();
}
#else /* #ifdef CONFIG_TREE_PREEMPT_RCU */
+static struct rcu_state *rcu_state = &rcu_sched_state;
+
/*
* Tell them what RCU they are running.
*/
@@ -836,7 +896,7 @@ void rcu_force_quiescent_state(void)
EXPORT_SYMBOL_GPL(rcu_force_quiescent_state);
/*
- * Because preemptable RCU does not exist, we never have to check for
+ * Because preemptible RCU does not exist, we never have to check for
* CPUs being in quiescent states.
*/
static void rcu_preempt_note_context_switch(int cpu)
@@ -844,10 +904,10 @@ static void rcu_preempt_note_context_switch(int cpu)
}
/*
- * Because preemptable RCU does not exist, there are never any preempted
+ * Because preemptible RCU does not exist, there are never any preempted
* RCU readers.
*/
-static int rcu_preempted_readers(struct rcu_node *rnp)
+static int rcu_preempt_blocked_readers_cgp(struct rcu_node *rnp)
{
return 0;
}
@@ -862,10 +922,8 @@ static void rcu_report_unblock_qs_rnp(struct rcu_node *rnp, unsigned long flags)
#endif /* #ifdef CONFIG_HOTPLUG_CPU */
-#ifdef CONFIG_RCU_CPU_STALL_DETECTOR
-
/*
- * Because preemptable RCU does not exist, we never have to check for
+ * Because preemptible RCU does not exist, we never have to check for
* tasks blocked within RCU read-side critical sections.
*/
static void rcu_print_detail_task_stall(struct rcu_state *rsp)
@@ -873,7 +931,7 @@ static void rcu_print_detail_task_stall(struct rcu_state *rsp)
}
/*
- * Because preemptable RCU does not exist, we never have to check for
+ * Because preemptible RCU does not exist, we never have to check for
* tasks blocked within RCU read-side critical sections.
*/
static void rcu_print_task_stall(struct rcu_node *rnp)
@@ -888,10 +946,8 @@ static void rcu_preempt_stall_reset(void)
{
}
-#endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
-
/*
- * Because there is no preemptable RCU, there can be no readers blocked,
+ * Because there is no preemptible RCU, there can be no readers blocked,
* so there is no need to check for blocked tasks. So check only for
* bogus qsmask values.
*/
@@ -903,7 +959,7 @@ static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp)
#ifdef CONFIG_HOTPLUG_CPU
/*
- * Because preemptable RCU does not exist, it never needs to migrate
+ * Because preemptible RCU does not exist, it never needs to migrate
* tasks that were blocked within RCU read-side critical sections, and
* such non-existent tasks cannot possibly have been blocking the current
* grace period.
@@ -916,7 +972,7 @@ static int rcu_preempt_offline_tasks(struct rcu_state *rsp,
}
/*
- * Because preemptable RCU does not exist, it never needs CPU-offline
+ * Because preemptible RCU does not exist, it never needs CPU-offline
* processing.
*/
static void rcu_preempt_offline_cpu(int cpu)
@@ -926,7 +982,7 @@ static void rcu_preempt_offline_cpu(int cpu)
#endif /* #ifdef CONFIG_HOTPLUG_CPU */
/*
- * Because preemptable RCU does not exist, it never has any callbacks
+ * Because preemptible RCU does not exist, it never has any callbacks
* to check.
*/
static void rcu_preempt_check_callbacks(int cpu)
@@ -934,7 +990,7 @@ static void rcu_preempt_check_callbacks(int cpu)
}
/*
- * Because preemptable RCU does not exist, it never has any callbacks
+ * Because preemptible RCU does not exist, it never has any callbacks
* to process.
*/
static void rcu_preempt_process_callbacks(void)
@@ -943,7 +999,7 @@ static void rcu_preempt_process_callbacks(void)
/*
* Wait for an rcu-preempt grace period, but make it happen quickly.
- * But because preemptable RCU does not exist, map to rcu-sched.
+ * But because preemptible RCU does not exist, map to rcu-sched.
*/
void synchronize_rcu_expedited(void)
{
@@ -954,7 +1010,7 @@ EXPORT_SYMBOL_GPL(synchronize_rcu_expedited);
#ifdef CONFIG_HOTPLUG_CPU
/*
- * Because preemptable RCU does not exist, there is never any need to
+ * Because preemptible RCU does not exist, there is never any need to
* report on tasks preempted in RCU read-side critical sections during
* expedited RCU grace periods.
*/
@@ -966,7 +1022,7 @@ static void rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp)
#endif /* #ifdef CONFIG_HOTPLUG_CPU */
/*
- * Because preemptable RCU does not exist, it never has any work to do.
+ * Because preemptible RCU does not exist, it never has any work to do.
*/
static int rcu_preempt_pending(int cpu)
{
@@ -974,7 +1030,7 @@ static int rcu_preempt_pending(int cpu)
}
/*
- * Because preemptable RCU does not exist, it never needs any CPU.
+ * Because preemptible RCU does not exist, it never needs any CPU.
*/
static int rcu_preempt_needs_cpu(int cpu)
{
@@ -982,7 +1038,7 @@ static int rcu_preempt_needs_cpu(int cpu)
}
/*
- * Because preemptable RCU does not exist, rcu_barrier() is just
+ * Because preemptible RCU does not exist, rcu_barrier() is just
* another name for rcu_barrier_sched().
*/
void rcu_barrier(void)
@@ -992,7 +1048,7 @@ void rcu_barrier(void)
EXPORT_SYMBOL_GPL(rcu_barrier);
/*
- * Because preemptable RCU does not exist, there is no per-CPU
+ * Because preemptible RCU does not exist, there is no per-CPU
* data to initialize.
*/
static void __cpuinit rcu_preempt_init_percpu_data(int cpu)
@@ -1000,14 +1056,14 @@ static void __cpuinit rcu_preempt_init_percpu_data(int cpu)
}
/*
- * Because there is no preemptable RCU, there are no callbacks to move.
+ * Because there is no preemptible RCU, there are no callbacks to move.
*/
static void rcu_preempt_send_cbs_to_online(void)
{
}
/*
- * Because preemptable RCU does not exist, it need not be initialized.
+ * Because preemptible RCU does not exist, it need not be initialized.
*/
static void __init __rcu_init_preempt(void)
{
@@ -1015,6 +1071,276 @@ static void __init __rcu_init_preempt(void)
#endif /* #else #ifdef CONFIG_TREE_PREEMPT_RCU */
+#ifdef CONFIG_RCU_BOOST
+
+#include "rtmutex_common.h"
+
+#ifdef CONFIG_RCU_TRACE
+
+static void rcu_initiate_boost_trace(struct rcu_node *rnp)
+{
+ if (list_empty(&rnp->blkd_tasks))
+ rnp->n_balk_blkd_tasks++;
+ else if (rnp->exp_tasks == NULL && rnp->gp_tasks == NULL)
+ rnp->n_balk_exp_gp_tasks++;
+ else if (rnp->gp_tasks != NULL && rnp->boost_tasks != NULL)
+ rnp->n_balk_boost_tasks++;
+ else if (rnp->gp_tasks != NULL && rnp->qsmask != 0)
+ rnp->n_balk_notblocked++;
+ else if (rnp->gp_tasks != NULL &&
+ ULONG_CMP_LT(jiffies, rnp->boost_time))
+ rnp->n_balk_notyet++;
+ else
+ rnp->n_balk_nos++;
+}
+
+#else /* #ifdef CONFIG_RCU_TRACE */
+
+static void rcu_initiate_boost_trace(struct rcu_node *rnp)
+{
+}
+
+#endif /* #else #ifdef CONFIG_RCU_TRACE */
+
+/*
+ * Carry out RCU priority boosting on the task indicated by ->exp_tasks
+ * or ->boost_tasks, advancing the pointer to the next task in the
+ * ->blkd_tasks list.
+ *
+ * Note that irqs must be enabled: boosting the task can block.
+ * Returns 1 if there are more tasks needing to be boosted.
+ */
+static int rcu_boost(struct rcu_node *rnp)
+{
+ unsigned long flags;
+ struct rt_mutex mtx;
+ struct task_struct *t;
+ struct list_head *tb;
+
+ if (rnp->exp_tasks == NULL && rnp->boost_tasks == NULL)
+ return 0; /* Nothing left to boost. */
+
+ raw_spin_lock_irqsave(&rnp->lock, flags);
+
+ /*
+ * Recheck under the lock: all tasks in need of boosting
+ * might exit their RCU read-side critical sections on their own.
+ */
+ if (rnp->exp_tasks == NULL && rnp->boost_tasks == NULL) {
+ raw_spin_unlock_irqrestore(&rnp->lock, flags);
+ return 0;
+ }
+
+ /*
+ * Preferentially boost tasks blocking expedited grace periods.
+ * This cannot starve the normal grace periods because a second
+ * expedited grace period must boost all blocked tasks, including
+ * those blocking the pre-existing normal grace period.
+ */
+ if (rnp->exp_tasks != NULL) {
+ tb = rnp->exp_tasks;
+ rnp->n_exp_boosts++;
+ } else {
+ tb = rnp->boost_tasks;
+ rnp->n_normal_boosts++;
+ }
+ rnp->n_tasks_boosted++;
+
+ /*
+ * We boost task t by manufacturing an rt_mutex that appears to
+ * be held by task t. We leave a pointer to that rt_mutex where
+ * task t can find it, and task t will release the mutex when it
+ * exits its outermost RCU read-side critical section. Then
+ * simply acquiring this artificial rt_mutex will boost task
+ * t's priority. (Thanks to tglx for suggesting this approach!)
+ *
+ * Note that task t must acquire rnp->lock to remove itself from
+ * the ->blkd_tasks list, which it will do from exit() if from
+ * nowhere else. We therefore are guaranteed that task t will
+ * stay around at least until we drop rnp->lock. Note that
+ * rnp->lock also resolves races between our priority boosting
+ * and task t's exiting its outermost RCU read-side critical
+ * section.
+ */
+ t = container_of(tb, struct task_struct, rcu_node_entry);
+ rt_mutex_init_proxy_locked(&mtx, t);
+ t->rcu_boost_mutex = &mtx;
+ t->rcu_read_unlock_special |= RCU_READ_UNLOCK_BOOSTED;
+ raw_spin_unlock_irqrestore(&rnp->lock, flags);
+ rt_mutex_lock(&mtx); /* Side effect: boosts task t's priority. */
+ rt_mutex_unlock(&mtx); /* Keep lockdep happy. */
+
+ return rnp->exp_tasks != NULL || rnp->boost_tasks != NULL;
+}
+
+/*
+ * Timer handler to initiate waking up of boost kthreads that
+ * have yielded the CPU due to excessive numbers of tasks to
+ * boost. We wake up the per-rcu_node kthread, which in turn
+ * will wake up the booster kthread.
+ */
+static void rcu_boost_kthread_timer(unsigned long arg)
+{
+ invoke_rcu_node_kthread((struct rcu_node *)arg);
+}
+
+/*
+ * Priority-boosting kthread. One per leaf rcu_node and one for the
+ * root rcu_node.
+ */
+static int rcu_boost_kthread(void *arg)
+{
+ struct rcu_node *rnp = (struct rcu_node *)arg;
+ int spincnt = 0;
+ int more2boost;
+
+ for (;;) {
+ rnp->boost_kthread_status = RCU_KTHREAD_WAITING;
+ wait_event_interruptible(rnp->boost_wq, rnp->boost_tasks ||
+ rnp->exp_tasks);
+ rnp->boost_kthread_status = RCU_KTHREAD_RUNNING;
+ more2boost = rcu_boost(rnp);
+ if (more2boost)
+ spincnt++;
+ else
+ spincnt = 0;
+ if (spincnt > 10) {
+ rcu_yield(rcu_boost_kthread_timer, (unsigned long)rnp);
+ spincnt = 0;
+ }
+ }
+ /* NOTREACHED */
+ return 0;
+}
+
+/*
+ * Check to see if it is time to start boosting RCU readers that are
+ * blocking the current grace period, and, if so, tell the per-rcu_node
+ * kthread to start boosting them. If there is an expedited grace
+ * period in progress, it is always time to boost.
+ *
+ * The caller must hold rnp->lock, which this function releases,
+ * but irqs remain disabled. The ->boost_kthread_task is immortal,
+ * so we don't need to worry about it going away.
+ */
+static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags)
+{
+ struct task_struct *t;
+
+ if (!rcu_preempt_blocked_readers_cgp(rnp) && rnp->exp_tasks == NULL) {
+ rnp->n_balk_exp_gp_tasks++;
+ raw_spin_unlock_irqrestore(&rnp->lock, flags);
+ return;
+ }
+ if (rnp->exp_tasks != NULL ||
+ (rnp->gp_tasks != NULL &&
+ rnp->boost_tasks == NULL &&
+ rnp->qsmask == 0 &&
+ ULONG_CMP_GE(jiffies, rnp->boost_time))) {
+ if (rnp->exp_tasks == NULL)
+ rnp->boost_tasks = rnp->gp_tasks;
+ raw_spin_unlock_irqrestore(&rnp->lock, flags);
+ t = rnp->boost_kthread_task;
+ if (t != NULL)
+ wake_up_process(t);
+ } else {
+ rcu_initiate_boost_trace(rnp);
+ raw_spin_unlock_irqrestore(&rnp->lock, flags);
+ }
+}
+
+/*
+ * Set the affinity of the boost kthread. The CPU-hotplug locks are
+ * held, so no one should be messing with the existence of the boost
+ * kthread.
+ */
+static void rcu_boost_kthread_setaffinity(struct rcu_node *rnp,
+ cpumask_var_t cm)
+{
+ struct task_struct *t;
+
+ t = rnp->boost_kthread_task;
+ if (t != NULL)
+ set_cpus_allowed_ptr(rnp->boost_kthread_task, cm);
+}
+
+#define RCU_BOOST_DELAY_JIFFIES DIV_ROUND_UP(CONFIG_RCU_BOOST_DELAY * HZ, 1000)
+
+/*
+ * Do priority-boost accounting for the start of a new grace period.
+ */
+static void rcu_preempt_boost_start_gp(struct rcu_node *rnp)
+{
+ rnp->boost_time = jiffies + RCU_BOOST_DELAY_JIFFIES;
+}
+
+/*
+ * Initialize the RCU-boost waitqueue.
+ */
+static void __init rcu_init_boost_waitqueue(struct rcu_node *rnp)
+{
+ init_waitqueue_head(&rnp->boost_wq);
+}
+
+/*
+ * Create an RCU-boost kthread for the specified node if one does not
+ * already exist. We only create this kthread for preemptible RCU.
+ * Returns zero if all is well, a negated errno otherwise.
+ */
+static int __cpuinit rcu_spawn_one_boost_kthread(struct rcu_state *rsp,
+ struct rcu_node *rnp,
+ int rnp_index)
+{
+ unsigned long flags;
+ struct sched_param sp;
+ struct task_struct *t;
+
+ if (&rcu_preempt_state != rsp)
+ return 0;
+ if (rnp->boost_kthread_task != NULL)
+ return 0;
+ t = kthread_create(rcu_boost_kthread, (void *)rnp,
+ "rcub%d", rnp_index);
+ if (IS_ERR(t))
+ return PTR_ERR(t);
+ raw_spin_lock_irqsave(&rnp->lock, flags);
+ rnp->boost_kthread_task = t;
+ raw_spin_unlock_irqrestore(&rnp->lock, flags);
+ wake_up_process(t);
+ sp.sched_priority = RCU_KTHREAD_PRIO;
+ sched_setscheduler_nocheck(t, SCHED_FIFO, &sp);
+ return 0;
+}
+
+#else /* #ifdef CONFIG_RCU_BOOST */
+
+static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags)
+{
+ raw_spin_unlock_irqrestore(&rnp->lock, flags);
+}
+
+static void rcu_boost_kthread_setaffinity(struct rcu_node *rnp,
+ cpumask_var_t cm)
+{
+}
+
+static void rcu_preempt_boost_start_gp(struct rcu_node *rnp)
+{
+}
+
+static void __init rcu_init_boost_waitqueue(struct rcu_node *rnp)
+{
+}
+
+static int __cpuinit rcu_spawn_one_boost_kthread(struct rcu_state *rsp,
+ struct rcu_node *rnp,
+ int rnp_index)
+{
+ return 0;
+}
+
+#endif /* #else #ifdef CONFIG_RCU_BOOST */
+
#ifndef CONFIG_SMP
void synchronize_sched_expedited(void)
@@ -1187,8 +1513,8 @@ static DEFINE_PER_CPU(unsigned long, rcu_dyntick_holdoff);
*
* Because it is not legal to invoke rcu_process_callbacks() with irqs
* disabled, we do one pass of force_quiescent_state(), then do a
- * raise_softirq() to cause rcu_process_callbacks() to be invoked later.
- * The per-cpu rcu_dyntick_drain variable controls the sequencing.
+ * invoke_rcu_cpu_kthread() to cause rcu_process_callbacks() to be invoked
+ * later. The per-cpu rcu_dyntick_drain variable controls the sequencing.
*/
int rcu_needs_cpu(int cpu)
{
@@ -1239,7 +1565,7 @@ int rcu_needs_cpu(int cpu)
/* If RCU callbacks are still pending, RCU still needs this CPU. */
if (c)
- raise_softirq(RCU_SOFTIRQ);
+ invoke_rcu_cpu_kthread();
return c;
}
diff --git a/kernel/rcutree_trace.c b/kernel/rcutree_trace.c
index c8e97853b97..aa0fd72b4bc 100644
--- a/kernel/rcutree_trace.c
+++ b/kernel/rcutree_trace.c
@@ -46,6 +46,18 @@
#define RCU_TREE_NONCORE
#include "rcutree.h"
+DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_status);
+DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_cpu);
+DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_loops);
+DECLARE_PER_CPU(char, rcu_cpu_has_work);
+
+static char convert_kthread_status(unsigned int kthread_status)
+{
+ if (kthread_status > RCU_KTHREAD_MAX)
+ return '?';
+ return "SRWOY"[kthread_status];
+}
+
static void print_one_rcu_data(struct seq_file *m, struct rcu_data *rdp)
{
if (!rdp->beenonline)
@@ -64,7 +76,21 @@ static void print_one_rcu_data(struct seq_file *m, struct rcu_data *rdp)
rdp->dynticks_fqs);
#endif /* #ifdef CONFIG_NO_HZ */
seq_printf(m, " of=%lu ri=%lu", rdp->offline_fqs, rdp->resched_ipi);
- seq_printf(m, " ql=%ld b=%ld", rdp->qlen, rdp->blimit);
+ seq_printf(m, " ql=%ld qs=%c%c%c%c kt=%d/%c/%d ktl=%x b=%ld",
+ rdp->qlen,
+ ".N"[rdp->nxttail[RCU_NEXT_READY_TAIL] !=
+ rdp->nxttail[RCU_NEXT_TAIL]],
+ ".R"[rdp->nxttail[RCU_WAIT_TAIL] !=
+ rdp->nxttail[RCU_NEXT_READY_TAIL]],
+ ".W"[rdp->nxttail[RCU_DONE_TAIL] !=
+ rdp->nxttail[RCU_WAIT_TAIL]],
+ ".D"[&rdp->nxtlist != rdp->nxttail[RCU_DONE_TAIL]],
+ per_cpu(rcu_cpu_has_work, rdp->cpu),
+ convert_kthread_status(per_cpu(rcu_cpu_kthread_status,
+ rdp->cpu)),
+ per_cpu(rcu_cpu_kthread_cpu, rdp->cpu),
+ per_cpu(rcu_cpu_kthread_loops, rdp->cpu) & 0xffff,
+ rdp->blimit);
seq_printf(m, " ci=%lu co=%lu ca=%lu\n",
rdp->n_cbs_invoked, rdp->n_cbs_orphaned, rdp->n_cbs_adopted);
}
@@ -121,7 +147,18 @@ static void print_one_rcu_data_csv(struct seq_file *m, struct rcu_data *rdp)
rdp->dynticks_fqs);
#endif /* #ifdef CONFIG_NO_HZ */
seq_printf(m, ",%lu,%lu", rdp->offline_fqs, rdp->resched_ipi);
- seq_printf(m, ",%ld,%ld", rdp->qlen, rdp->blimit);
+ seq_printf(m, ",%ld,\"%c%c%c%c\",%d,\"%c\",%ld", rdp->qlen,
+ ".N"[rdp->nxttail[RCU_NEXT_READY_TAIL] !=
+ rdp->nxttail[RCU_NEXT_TAIL]],
+ ".R"[rdp->nxttail[RCU_WAIT_TAIL] !=
+ rdp->nxttail[RCU_NEXT_READY_TAIL]],
+ ".W"[rdp->nxttail[RCU_DONE_TAIL] !=
+ rdp->nxttail[RCU_WAIT_TAIL]],
+ ".D"[&rdp->nxtlist != rdp->nxttail[RCU_DONE_TAIL]],
+ per_cpu(rcu_cpu_has_work, rdp->cpu),
+ convert_kthread_status(per_cpu(rcu_cpu_kthread_status,
+ rdp->cpu)),
+ rdp->blimit);
seq_printf(m, ",%lu,%lu,%lu\n",
rdp->n_cbs_invoked, rdp->n_cbs_orphaned, rdp->n_cbs_adopted);
}
@@ -157,11 +194,76 @@ static const struct file_operations rcudata_csv_fops = {
.release = single_release,
};
+#ifdef CONFIG_RCU_BOOST
+
+static void print_one_rcu_node_boost(struct seq_file *m, struct rcu_node *rnp)
+{
+ seq_printf(m, "%d:%d tasks=%c%c%c%c kt=%c ntb=%lu neb=%lu nnb=%lu "
+ "j=%04x bt=%04x\n",
+ rnp->grplo, rnp->grphi,
+ "T."[list_empty(&rnp->blkd_tasks)],
+ "N."[!rnp->gp_tasks],
+ "E."[!rnp->exp_tasks],
+ "B."[!rnp->boost_tasks],
+ convert_kthread_status(rnp->boost_kthread_status),
+ rnp->n_tasks_boosted, rnp->n_exp_boosts,
+ rnp->n_normal_boosts,
+ (int)(jiffies & 0xffff),
+ (int)(rnp->boost_time & 0xffff));
+ seq_printf(m, "%s: nt=%lu egt=%lu bt=%lu nb=%lu ny=%lu nos=%lu\n",
+ " balk",
+ rnp->n_balk_blkd_tasks,
+ rnp->n_balk_exp_gp_tasks,
+ rnp->n_balk_boost_tasks,
+ rnp->n_balk_notblocked,
+ rnp->n_balk_notyet,
+ rnp->n_balk_nos);
+}
+
+static int show_rcu_node_boost(struct seq_file *m, void *unused)
+{
+ struct rcu_node *rnp;
+
+ rcu_for_each_leaf_node(&rcu_preempt_state, rnp)
+ print_one_rcu_node_boost(m, rnp);
+ return 0;
+}
+
+static int rcu_node_boost_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, show_rcu_node_boost, NULL);
+}
+
+static const struct file_operations rcu_node_boost_fops = {
+ .owner = THIS_MODULE,
+ .open = rcu_node_boost_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+/*
+ * Create the rcuboost debugfs entry. Standard error return.
+ */
+static int rcu_boost_trace_create_file(struct dentry *rcudir)
+{
+ return !debugfs_create_file("rcuboost", 0444, rcudir, NULL,
+ &rcu_node_boost_fops);
+}
+
+#else /* #ifdef CONFIG_RCU_BOOST */
+
+static int rcu_boost_trace_create_file(struct dentry *rcudir)
+{
+ return 0; /* There cannot be an error if we didn't create it! */
+}
+
+#endif /* #else #ifdef CONFIG_RCU_BOOST */
+
static void print_one_rcu_state(struct seq_file *m, struct rcu_state *rsp)
{
unsigned long gpnum;
int level = 0;
- int phase;
struct rcu_node *rnp;
gpnum = rsp->gpnum;
@@ -178,13 +280,11 @@ static void print_one_rcu_state(struct seq_file *m, struct rcu_state *rsp)
seq_puts(m, "\n");
level = rnp->level;
}
- phase = gpnum & 0x1;
- seq_printf(m, "%lx/%lx %c%c>%c%c %d:%d ^%d ",
+ seq_printf(m, "%lx/%lx %c%c>%c %d:%d ^%d ",
rnp->qsmask, rnp->qsmaskinit,
- "T."[list_empty(&rnp->blocked_tasks[phase])],
- "E."[list_empty(&rnp->blocked_tasks[phase + 2])],
- "T."[list_empty(&rnp->blocked_tasks[!phase])],
- "E."[list_empty(&rnp->blocked_tasks[!phase + 2])],
+ ".G"[rnp->gp_tasks != NULL],
+ ".E"[rnp->exp_tasks != NULL],
+ ".T"[!list_empty(&rnp->blkd_tasks)],
rnp->grplo, rnp->grphi, rnp->grpnum);
}
seq_puts(m, "\n");
@@ -216,16 +316,35 @@ static const struct file_operations rcuhier_fops = {
.release = single_release,
};
+static void show_one_rcugp(struct seq_file *m, struct rcu_state *rsp)
+{
+ unsigned long flags;
+ unsigned long completed;
+ unsigned long gpnum;
+ unsigned long gpage;
+ unsigned long gpmax;
+ struct rcu_node *rnp = &rsp->node[0];
+
+ raw_spin_lock_irqsave(&rnp->lock, flags);
+ completed = rsp->completed;
+ gpnum = rsp->gpnum;
+ if (rsp->completed == rsp->gpnum)
+ gpage = 0;
+ else
+ gpage = jiffies - rsp->gp_start;
+ gpmax = rsp->gp_max;
+ raw_spin_unlock_irqrestore(&rnp->lock, flags);
+ seq_printf(m, "%s: completed=%ld gpnum=%lu age=%ld max=%ld\n",
+ rsp->name, completed, gpnum, gpage, gpmax);
+}
+
static int show_rcugp(struct seq_file *m, void *unused)
{
#ifdef CONFIG_TREE_PREEMPT_RCU
- seq_printf(m, "rcu_preempt: completed=%ld gpnum=%lu\n",
- rcu_preempt_state.completed, rcu_preempt_state.gpnum);
+ show_one_rcugp(m, &rcu_preempt_state);
#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
- seq_printf(m, "rcu_sched: completed=%ld gpnum=%lu\n",
- rcu_sched_state.completed, rcu_sched_state.gpnum);
- seq_printf(m, "rcu_bh: completed=%ld gpnum=%lu\n",
- rcu_bh_state.completed, rcu_bh_state.gpnum);
+ show_one_rcugp(m, &rcu_sched_state);
+ show_one_rcugp(m, &rcu_bh_state);
return 0;
}
@@ -298,6 +417,29 @@ static const struct file_operations rcu_pending_fops = {
.release = single_release,
};
+static int show_rcutorture(struct seq_file *m, void *unused)
+{
+ seq_printf(m, "rcutorture test sequence: %lu %s\n",
+ rcutorture_testseq >> 1,
+ (rcutorture_testseq & 0x1) ? "(test in progress)" : "");
+ seq_printf(m, "rcutorture update version number: %lu\n",
+ rcutorture_vernum);
+ return 0;
+}
+
+static int rcutorture_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, show_rcutorture, NULL);
+}
+
+static const struct file_operations rcutorture_fops = {
+ .owner = THIS_MODULE,
+ .open = rcutorture_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
static struct dentry *rcudir;
static int __init rcutree_trace_init(void)
@@ -318,6 +460,9 @@ static int __init rcutree_trace_init(void)
if (!retval)
goto free_out;
+ if (rcu_boost_trace_create_file(rcudir))
+ goto free_out;
+
retval = debugfs_create_file("rcugp", 0444, rcudir, NULL, &rcugp_fops);
if (!retval)
goto free_out;
@@ -331,6 +476,11 @@ static int __init rcutree_trace_init(void)
NULL, &rcu_pending_fops);
if (!retval)
goto free_out;
+
+ retval = debugfs_create_file("rcutorture", 0444, rcudir,
+ NULL, &rcutorture_fops);
+ if (!retval)
+ goto free_out;
return 0;
free_out:
debugfs_remove_recursive(rcudir);
diff --git a/kernel/sched.c b/kernel/sched.c
index 312f8b95c2d..c62acf45d3b 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -231,7 +231,7 @@ static void destroy_rt_bandwidth(struct rt_bandwidth *rt_b)
#endif
/*
- * sched_domains_mutex serializes calls to arch_init_sched_domains,
+ * sched_domains_mutex serializes calls to init_sched_domains,
* detach_destroy_domains and partition_sched_domains.
*/
static DEFINE_MUTEX(sched_domains_mutex);
@@ -312,6 +312,9 @@ struct cfs_rq {
u64 exec_clock;
u64 min_vruntime;
+#ifndef CONFIG_64BIT
+ u64 min_vruntime_copy;
+#endif
struct rb_root tasks_timeline;
struct rb_node *rb_leftmost;
@@ -325,7 +328,9 @@ struct cfs_rq {
*/
struct sched_entity *curr, *next, *last, *skip;
+#ifdef CONFIG_SCHED_DEBUG
unsigned int nr_spread_over;
+#endif
#ifdef CONFIG_FAIR_GROUP_SCHED
struct rq *rq; /* cpu runqueue to which this cfs_rq is attached */
@@ -417,6 +422,7 @@ struct rt_rq {
*/
struct root_domain {
atomic_t refcount;
+ struct rcu_head rcu;
cpumask_var_t span;
cpumask_var_t online;
@@ -460,7 +466,7 @@ struct rq {
u64 nohz_stamp;
unsigned char nohz_balance_kick;
#endif
- unsigned int skip_clock_update;
+ int skip_clock_update;
/* capture load from *all* tasks on this cpu: */
struct load_weight load;
@@ -553,6 +559,10 @@ struct rq {
unsigned int ttwu_count;
unsigned int ttwu_local;
#endif
+
+#ifdef CONFIG_SMP
+ struct task_struct *wake_list;
+#endif
};
static DEFINE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
@@ -571,7 +581,7 @@ static inline int cpu_of(struct rq *rq)
#define rcu_dereference_check_sched_domain(p) \
rcu_dereference_check((p), \
- rcu_read_lock_sched_held() || \
+ rcu_read_lock_held() || \
lockdep_is_held(&sched_domains_mutex))
/*
@@ -596,7 +606,7 @@ static inline int cpu_of(struct rq *rq)
* Return the group to which this tasks belongs.
*
* We use task_subsys_state_check() and extend the RCU verification
- * with lockdep_is_held(&task_rq(p)->lock) because cpu_cgroup_attach()
+ * with lockdep_is_held(&p->pi_lock) because cpu_cgroup_attach()
* holds that lock for each task it moves into the cgroup. Therefore
* by holding that lock, we pin the task to the current cgroup.
*/
@@ -606,7 +616,7 @@ static inline struct task_group *task_group(struct task_struct *p)
struct cgroup_subsys_state *css;
css = task_subsys_state_check(p, cpu_cgroup_subsys_id,
- lockdep_is_held(&task_rq(p)->lock));
+ lockdep_is_held(&p->pi_lock));
tg = container_of(css, struct task_group, css);
return autogroup_task_group(p, tg);
@@ -642,7 +652,7 @@ static void update_rq_clock(struct rq *rq)
{
s64 delta;
- if (rq->skip_clock_update)
+ if (rq->skip_clock_update > 0)
return;
delta = sched_clock_cpu(cpu_of(rq)) - rq->clock;
@@ -838,18 +848,39 @@ static inline int task_current(struct rq *rq, struct task_struct *p)
return rq->curr == p;
}
-#ifndef __ARCH_WANT_UNLOCKED_CTXSW
static inline int task_running(struct rq *rq, struct task_struct *p)
{
+#ifdef CONFIG_SMP
+ return p->on_cpu;
+#else
return task_current(rq, p);
+#endif
}
+#ifndef __ARCH_WANT_UNLOCKED_CTXSW
static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next)
{
+#ifdef CONFIG_SMP
+ /*
+ * We can optimise this out completely for !SMP, because the
+ * SMP rebalancing from interrupt is the only thing that cares
+ * here.
+ */
+ next->on_cpu = 1;
+#endif
}
static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
{
+#ifdef CONFIG_SMP
+ /*
+ * After ->on_cpu is cleared, the task can be moved to a different CPU.
+ * We must ensure this doesn't happen until the switch is completely
+ * finished.
+ */
+ smp_wmb();
+ prev->on_cpu = 0;
+#endif
#ifdef CONFIG_DEBUG_SPINLOCK
/* this is a valid case when another task releases the spinlock */
rq->lock.owner = current;
@@ -865,15 +896,6 @@ static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
}
#else /* __ARCH_WANT_UNLOCKED_CTXSW */
-static inline int task_running(struct rq *rq, struct task_struct *p)
-{
-#ifdef CONFIG_SMP
- return p->oncpu;
-#else
- return task_current(rq, p);
-#endif
-}
-
static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next)
{
#ifdef CONFIG_SMP
@@ -882,7 +904,7 @@ static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next)
* SMP rebalancing from interrupt is the only thing that cares
* here.
*/
- next->oncpu = 1;
+ next->on_cpu = 1;
#endif
#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
raw_spin_unlock_irq(&rq->lock);
@@ -895,12 +917,12 @@ static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
{
#ifdef CONFIG_SMP
/*
- * After ->oncpu is cleared, the task can be moved to a different CPU.
+ * After ->on_cpu is cleared, the task can be moved to a different CPU.
* We must ensure this doesn't happen until the switch is completely
* finished.
*/
smp_wmb();
- prev->oncpu = 0;
+ prev->on_cpu = 0;
#endif
#ifndef __ARCH_WANT_INTERRUPTS_ON_CTXSW
local_irq_enable();
@@ -909,23 +931,15 @@ static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
#endif /* __ARCH_WANT_UNLOCKED_CTXSW */
/*
- * Check whether the task is waking, we use this to synchronize ->cpus_allowed
- * against ttwu().
- */
-static inline int task_is_waking(struct task_struct *p)
-{
- return unlikely(p->state == TASK_WAKING);
-}
-
-/*
- * __task_rq_lock - lock the runqueue a given task resides on.
- * Must be called interrupts disabled.
+ * __task_rq_lock - lock the rq @p resides on.
*/
static inline struct rq *__task_rq_lock(struct task_struct *p)
__acquires(rq->lock)
{
struct rq *rq;
+ lockdep_assert_held(&p->pi_lock);
+
for (;;) {
rq = task_rq(p);
raw_spin_lock(&rq->lock);
@@ -936,22 +950,22 @@ static inline struct rq *__task_rq_lock(struct task_struct *p)
}
/*
- * task_rq_lock - lock the runqueue a given task resides on and disable
- * interrupts. Note the ordering: we can safely lookup the task_rq without
- * explicitly disabling preemption.
+ * task_rq_lock - lock p->pi_lock and lock the rq @p resides on.
*/
static struct rq *task_rq_lock(struct task_struct *p, unsigned long *flags)
+ __acquires(p->pi_lock)
__acquires(rq->lock)
{
struct rq *rq;
for (;;) {
- local_irq_save(*flags);
+ raw_spin_lock_irqsave(&p->pi_lock, *flags);
rq = task_rq(p);
raw_spin_lock(&rq->lock);
if (likely(rq == task_rq(p)))
return rq;
- raw_spin_unlock_irqrestore(&rq->lock, *flags);
+ raw_spin_unlock(&rq->lock);
+ raw_spin_unlock_irqrestore(&p->pi_lock, *flags);
}
}
@@ -961,10 +975,13 @@ static void __task_rq_unlock(struct rq *rq)
raw_spin_unlock(&rq->lock);
}
-static inline void task_rq_unlock(struct rq *rq, unsigned long *flags)
+static inline void
+task_rq_unlock(struct rq *rq, struct task_struct *p, unsigned long *flags)
__releases(rq->lock)
+ __releases(p->pi_lock)
{
- raw_spin_unlock_irqrestore(&rq->lock, *flags);
+ raw_spin_unlock(&rq->lock);
+ raw_spin_unlock_irqrestore(&p->pi_lock, *flags);
}
/*
@@ -1193,11 +1210,17 @@ int get_nohz_timer_target(void)
int i;
struct sched_domain *sd;
+ rcu_read_lock();
for_each_domain(cpu, sd) {
- for_each_cpu(i, sched_domain_span(sd))
- if (!idle_cpu(i))
- return i;
+ for_each_cpu(i, sched_domain_span(sd)) {
+ if (!idle_cpu(i)) {
+ cpu = i;
+ goto unlock;
+ }
+ }
}
+unlock:
+ rcu_read_unlock();
return cpu;
}
/*
@@ -1307,15 +1330,15 @@ calc_delta_mine(unsigned long delta_exec, unsigned long weight,
{
u64 tmp;
+ tmp = (u64)delta_exec * weight;
+
if (!lw->inv_weight) {
if (BITS_PER_LONG > 32 && unlikely(lw->weight >= WMULT_CONST))
lw->inv_weight = 1;
else
- lw->inv_weight = 1 + (WMULT_CONST-lw->weight/2)
- / (lw->weight+1);
+ lw->inv_weight = WMULT_CONST / lw->weight;
}
- tmp = (u64)delta_exec * weight;
/*
* Check whether we'd overflow the 64-bit multiplication:
*/
@@ -1773,7 +1796,6 @@ static void enqueue_task(struct rq *rq, struct task_struct *p, int flags)
update_rq_clock(rq);
sched_info_queued(p);
p->sched_class->enqueue_task(rq, p, flags);
- p->se.on_rq = 1;
}
static void dequeue_task(struct rq *rq, struct task_struct *p, int flags)
@@ -1781,7 +1803,6 @@ static void dequeue_task(struct rq *rq, struct task_struct *p, int flags)
update_rq_clock(rq);
sched_info_dequeued(p);
p->sched_class->dequeue_task(rq, p, flags);
- p->se.on_rq = 0;
}
/*
@@ -2116,7 +2137,7 @@ static void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags)
* A queue event has occurred, and we're going to schedule. In
* this case, we can save a useless back to back clock update.
*/
- if (rq->curr->se.on_rq && test_tsk_need_resched(rq->curr))
+ if (rq->curr->on_rq && test_tsk_need_resched(rq->curr))
rq->skip_clock_update = 1;
}
@@ -2162,6 +2183,11 @@ void set_task_cpu(struct task_struct *p, unsigned int new_cpu)
*/
WARN_ON_ONCE(p->state != TASK_RUNNING && p->state != TASK_WAKING &&
!(task_thread_info(p)->preempt_count & PREEMPT_ACTIVE));
+
+#ifdef CONFIG_LOCKDEP
+ WARN_ON_ONCE(debug_locks && !(lockdep_is_held(&p->pi_lock) ||
+ lockdep_is_held(&task_rq(p)->lock)));
+#endif
#endif
trace_sched_migrate_task(p, new_cpu);
@@ -2182,19 +2208,6 @@ struct migration_arg {
static int migration_cpu_stop(void *data);
/*
- * The task's runqueue lock must be held.
- * Returns true if you have to wait for migration thread.
- */
-static bool migrate_task(struct task_struct *p, struct rq *rq)
-{
- /*
- * If the task is not on a runqueue (and not running), then
- * the next wake-up will properly place the task.
- */
- return p->se.on_rq || task_running(rq, p);
-}
-
-/*
* wait_task_inactive - wait for a thread to unschedule.
*
* If @match_state is nonzero, it's the @p->state value just checked and
@@ -2251,11 +2264,11 @@ unsigned long wait_task_inactive(struct task_struct *p, long match_state)
rq = task_rq_lock(p, &flags);
trace_sched_wait_task(p);
running = task_running(rq, p);
- on_rq = p->se.on_rq;
+ on_rq = p->on_rq;
ncsw = 0;
if (!match_state || p->state == match_state)
ncsw = p->nvcsw | LONG_MIN; /* sets MSB */
- task_rq_unlock(rq, &flags);
+ task_rq_unlock(rq, p, &flags);
/*
* If it changed from the expected state, bail out now.
@@ -2330,7 +2343,7 @@ EXPORT_SYMBOL_GPL(kick_process);
#ifdef CONFIG_SMP
/*
- * ->cpus_allowed is protected by either TASK_WAKING or rq->lock held.
+ * ->cpus_allowed is protected by both rq->lock and p->pi_lock
*/
static int select_fallback_rq(int cpu, struct task_struct *p)
{
@@ -2363,12 +2376,12 @@ static int select_fallback_rq(int cpu, struct task_struct *p)
}
/*
- * The caller (fork, wakeup) owns TASK_WAKING, ->cpus_allowed is stable.
+ * The caller (fork, wakeup) owns p->pi_lock, ->cpus_allowed is stable.
*/
static inline
-int select_task_rq(struct rq *rq, struct task_struct *p, int sd_flags, int wake_flags)
+int select_task_rq(struct task_struct *p, int sd_flags, int wake_flags)
{
- int cpu = p->sched_class->select_task_rq(rq, p, sd_flags, wake_flags);
+ int cpu = p->sched_class->select_task_rq(p, sd_flags, wake_flags);
/*
* In order not to call set_task_cpu() on a blocking task we need
@@ -2394,27 +2407,62 @@ static void update_avg(u64 *avg, u64 sample)
}
#endif
-static inline void ttwu_activate(struct task_struct *p, struct rq *rq,
- bool is_sync, bool is_migrate, bool is_local,
- unsigned long en_flags)
+static void
+ttwu_stat(struct task_struct *p, int cpu, int wake_flags)
{
+#ifdef CONFIG_SCHEDSTATS
+ struct rq *rq = this_rq();
+
+#ifdef CONFIG_SMP
+ int this_cpu = smp_processor_id();
+
+ if (cpu == this_cpu) {
+ schedstat_inc(rq, ttwu_local);
+ schedstat_inc(p, se.statistics.nr_wakeups_local);
+ } else {
+ struct sched_domain *sd;
+
+ schedstat_inc(p, se.statistics.nr_wakeups_remote);
+ rcu_read_lock();
+ for_each_domain(this_cpu, sd) {
+ if (cpumask_test_cpu(cpu, sched_domain_span(sd))) {
+ schedstat_inc(sd, ttwu_wake_remote);
+ break;
+ }
+ }
+ rcu_read_unlock();
+ }
+#endif /* CONFIG_SMP */
+
+ schedstat_inc(rq, ttwu_count);
schedstat_inc(p, se.statistics.nr_wakeups);
- if (is_sync)
+
+ if (wake_flags & WF_SYNC)
schedstat_inc(p, se.statistics.nr_wakeups_sync);
- if (is_migrate)
+
+ if (cpu != task_cpu(p))
schedstat_inc(p, se.statistics.nr_wakeups_migrate);
- if (is_local)
- schedstat_inc(p, se.statistics.nr_wakeups_local);
- else
- schedstat_inc(p, se.statistics.nr_wakeups_remote);
+#endif /* CONFIG_SCHEDSTATS */
+}
+
+static void ttwu_activate(struct rq *rq, struct task_struct *p, int en_flags)
+{
activate_task(rq, p, en_flags);
+ p->on_rq = 1;
+
+ /* if a worker is waking up, notify workqueue */
+ if (p->flags & PF_WQ_WORKER)
+ wq_worker_waking_up(p, cpu_of(rq));
}
-static inline void ttwu_post_activation(struct task_struct *p, struct rq *rq,
- int wake_flags, bool success)
+/*
+ * Mark the task runnable and perform wakeup-preemption.
+ */
+static void
+ttwu_do_wakeup(struct rq *rq, struct task_struct *p, int wake_flags)
{
- trace_sched_wakeup(p, success);
+ trace_sched_wakeup(p, true);
check_preempt_curr(rq, p, wake_flags);
p->state = TASK_RUNNING;
@@ -2433,9 +2481,99 @@ static inline void ttwu_post_activation(struct task_struct *p, struct rq *rq,
rq->idle_stamp = 0;
}
#endif
- /* if a worker is waking up, notify workqueue */
- if ((p->flags & PF_WQ_WORKER) && success)
- wq_worker_waking_up(p, cpu_of(rq));
+}
+
+static void
+ttwu_do_activate(struct rq *rq, struct task_struct *p, int wake_flags)
+{
+#ifdef CONFIG_SMP
+ if (p->sched_contributes_to_load)
+ rq->nr_uninterruptible--;
+#endif
+
+ ttwu_activate(rq, p, ENQUEUE_WAKEUP | ENQUEUE_WAKING);
+ ttwu_do_wakeup(rq, p, wake_flags);
+}
+
+/*
+ * Called in case the task @p isn't fully descheduled from its runqueue,
+ * in this case we must do a remote wakeup. Its a 'light' wakeup though,
+ * since all we need to do is flip p->state to TASK_RUNNING, since
+ * the task is still ->on_rq.
+ */
+static int ttwu_remote(struct task_struct *p, int wake_flags)
+{
+ struct rq *rq;
+ int ret = 0;
+
+ rq = __task_rq_lock(p);
+ if (p->on_rq) {
+ ttwu_do_wakeup(rq, p, wake_flags);
+ ret = 1;
+ }
+ __task_rq_unlock(rq);
+
+ return ret;
+}
+
+#ifdef CONFIG_SMP
+static void sched_ttwu_pending(void)
+{
+ struct rq *rq = this_rq();
+ struct task_struct *list = xchg(&rq->wake_list, NULL);
+
+ if (!list)
+ return;
+
+ raw_spin_lock(&rq->lock);
+
+ while (list) {
+ struct task_struct *p = list;
+ list = list->wake_entry;
+ ttwu_do_activate(rq, p, 0);
+ }
+
+ raw_spin_unlock(&rq->lock);
+}
+
+void scheduler_ipi(void)
+{
+ sched_ttwu_pending();
+}
+
+static void ttwu_queue_remote(struct task_struct *p, int cpu)
+{
+ struct rq *rq = cpu_rq(cpu);
+ struct task_struct *next = rq->wake_list;
+
+ for (;;) {
+ struct task_struct *old = next;
+
+ p->wake_entry = next;
+ next = cmpxchg(&rq->wake_list, old, p);
+ if (next == old)
+ break;
+ }
+
+ if (!next)
+ smp_send_reschedule(cpu);
+}
+#endif
+
+static void ttwu_queue(struct task_struct *p, int cpu)
+{
+ struct rq *rq = cpu_rq(cpu);
+
+#if defined(CONFIG_SMP) && defined(CONFIG_SCHED_TTWU_QUEUE)
+ if (sched_feat(TTWU_QUEUE) && cpu != smp_processor_id()) {
+ ttwu_queue_remote(p, cpu);
+ return;
+ }
+#endif
+
+ raw_spin_lock(&rq->lock);
+ ttwu_do_activate(rq, p, 0);
+ raw_spin_unlock(&rq->lock);
}
/**
@@ -2453,92 +2591,64 @@ static inline void ttwu_post_activation(struct task_struct *p, struct rq *rq,
* Returns %true if @p was woken up, %false if it was already running
* or @state didn't match @p's state.
*/
-static int try_to_wake_up(struct task_struct *p, unsigned int state,
- int wake_flags)
+static int
+try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
{
- int cpu, orig_cpu, this_cpu, success = 0;
unsigned long flags;
- unsigned long en_flags = ENQUEUE_WAKEUP;
- struct rq *rq;
-
- this_cpu = get_cpu();
+ int cpu, success = 0;
smp_wmb();
- rq = task_rq_lock(p, &flags);
+ raw_spin_lock_irqsave(&p->pi_lock, flags);
if (!(p->state & state))
goto out;
- if (p->se.on_rq)
- goto out_running;
-
+ success = 1; /* we're going to change ->state */
cpu = task_cpu(p);
- orig_cpu = cpu;
-#ifdef CONFIG_SMP
- if (unlikely(task_running(rq, p)))
- goto out_activate;
+ if (p->on_rq && ttwu_remote(p, wake_flags))
+ goto stat;
+#ifdef CONFIG_SMP
/*
- * In order to handle concurrent wakeups and release the rq->lock
- * we put the task in TASK_WAKING state.
- *
- * First fix up the nr_uninterruptible count:
+ * If the owning (remote) cpu is still in the middle of schedule() with
+ * this task as prev, wait until its done referencing the task.
*/
- if (task_contributes_to_load(p)) {
- if (likely(cpu_online(orig_cpu)))
- rq->nr_uninterruptible--;
- else
- this_rq()->nr_uninterruptible--;
- }
- p->state = TASK_WAKING;
-
- if (p->sched_class->task_waking) {
- p->sched_class->task_waking(rq, p);
- en_flags |= ENQUEUE_WAKING;
+ while (p->on_cpu) {
+#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
+ /*
+ * If called from interrupt context we could have landed in the
+ * middle of schedule(), in this case we should take care not
+ * to spin on ->on_cpu if p is current, since that would
+ * deadlock.
+ */
+ if (p == current) {
+ ttwu_queue(p, cpu);
+ goto stat;
+ }
+#endif
+ cpu_relax();
}
-
- cpu = select_task_rq(rq, p, SD_BALANCE_WAKE, wake_flags);
- if (cpu != orig_cpu)
- set_task_cpu(p, cpu);
- __task_rq_unlock(rq);
-
- rq = cpu_rq(cpu);
- raw_spin_lock(&rq->lock);
-
/*
- * We migrated the task without holding either rq->lock, however
- * since the task is not on the task list itself, nobody else
- * will try and migrate the task, hence the rq should match the
- * cpu we just moved it to.
+ * Pairs with the smp_wmb() in finish_lock_switch().
*/
- WARN_ON(task_cpu(p) != cpu);
- WARN_ON(p->state != TASK_WAKING);
+ smp_rmb();
-#ifdef CONFIG_SCHEDSTATS
- schedstat_inc(rq, ttwu_count);
- if (cpu == this_cpu)
- schedstat_inc(rq, ttwu_local);
- else {
- struct sched_domain *sd;
- for_each_domain(this_cpu, sd) {
- if (cpumask_test_cpu(cpu, sched_domain_span(sd))) {
- schedstat_inc(sd, ttwu_wake_remote);
- break;
- }
- }
- }
-#endif /* CONFIG_SCHEDSTATS */
+ p->sched_contributes_to_load = !!task_contributes_to_load(p);
+ p->state = TASK_WAKING;
+
+ if (p->sched_class->task_waking)
+ p->sched_class->task_waking(p);
-out_activate:
+ cpu = select_task_rq(p, SD_BALANCE_WAKE, wake_flags);
+ if (task_cpu(p) != cpu)
+ set_task_cpu(p, cpu);
#endif /* CONFIG_SMP */
- ttwu_activate(p, rq, wake_flags & WF_SYNC, orig_cpu != cpu,
- cpu == this_cpu, en_flags);
- success = 1;
-out_running:
- ttwu_post_activation(p, rq, wake_flags, success);
+
+ ttwu_queue(p, cpu);
+stat:
+ ttwu_stat(p, cpu, wake_flags);
out:
- task_rq_unlock(rq, &flags);
- put_cpu();
+ raw_spin_unlock_irqrestore(&p->pi_lock, flags);
return success;
}
@@ -2547,31 +2657,34 @@ out:
* try_to_wake_up_local - try to wake up a local task with rq lock held
* @p: the thread to be awakened
*
- * Put @p on the run-queue if it's not already there. The caller must
+ * Put @p on the run-queue if it's not already there. The caller must
* ensure that this_rq() is locked, @p is bound to this_rq() and not
- * the current task. this_rq() stays locked over invocation.
+ * the current task.
*/
static void try_to_wake_up_local(struct task_struct *p)
{
struct rq *rq = task_rq(p);
- bool success = false;
BUG_ON(rq != this_rq());
BUG_ON(p == current);
lockdep_assert_held(&rq->lock);
+ if (!raw_spin_trylock(&p->pi_lock)) {
+ raw_spin_unlock(&rq->lock);
+ raw_spin_lock(&p->pi_lock);
+ raw_spin_lock(&rq->lock);
+ }
+
if (!(p->state & TASK_NORMAL))
- return;
+ goto out;
- if (!p->se.on_rq) {
- if (likely(!task_running(rq, p))) {
- schedstat_inc(rq, ttwu_count);
- schedstat_inc(rq, ttwu_local);
- }
- ttwu_activate(p, rq, false, false, true, ENQUEUE_WAKEUP);
- success = true;
- }
- ttwu_post_activation(p, rq, 0, success);
+ if (!p->on_rq)
+ ttwu_activate(rq, p, ENQUEUE_WAKEUP);
+
+ ttwu_do_wakeup(rq, p, 0);
+ ttwu_stat(p, smp_processor_id(), 0);
+out:
+ raw_spin_unlock(&p->pi_lock);
}
/**
@@ -2604,19 +2717,21 @@ int wake_up_state(struct task_struct *p, unsigned int state)
*/
static void __sched_fork(struct task_struct *p)
{
+ p->on_rq = 0;
+
+ p->se.on_rq = 0;
p->se.exec_start = 0;
p->se.sum_exec_runtime = 0;
p->se.prev_sum_exec_runtime = 0;
p->se.nr_migrations = 0;
p->se.vruntime = 0;
+ INIT_LIST_HEAD(&p->se.group_node);
#ifdef CONFIG_SCHEDSTATS
memset(&p->se.statistics, 0, sizeof(p->se.statistics));
#endif
INIT_LIST_HEAD(&p->rt.run_list);
- p->se.on_rq = 0;
- INIT_LIST_HEAD(&p->se.group_node);
#ifdef CONFIG_PREEMPT_NOTIFIERS
INIT_HLIST_HEAD(&p->preempt_notifiers);
@@ -2626,8 +2741,9 @@ static void __sched_fork(struct task_struct *p)
/*
* fork()/clone()-time setup:
*/
-void sched_fork(struct task_struct *p, int clone_flags)
+void sched_fork(struct task_struct *p)
{
+ unsigned long flags;
int cpu = get_cpu();
__sched_fork(p);
@@ -2678,16 +2794,16 @@ void sched_fork(struct task_struct *p, int clone_flags)
*
* Silence PROVE_RCU.
*/
- rcu_read_lock();
+ raw_spin_lock_irqsave(&p->pi_lock, flags);
set_task_cpu(p, cpu);
- rcu_read_unlock();
+ raw_spin_unlock_irqrestore(&p->pi_lock, flags);
#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
if (likely(sched_info_on()))
memset(&p->sched_info, 0, sizeof(p->sched_info));
#endif
-#if defined(CONFIG_SMP) && defined(__ARCH_WANT_UNLOCKED_CTXSW)
- p->oncpu = 0;
+#if defined(CONFIG_SMP)
+ p->on_cpu = 0;
#endif
#ifdef CONFIG_PREEMPT
/* Want to start with kernel preemption disabled. */
@@ -2707,41 +2823,31 @@ void sched_fork(struct task_struct *p, int clone_flags)
* that must be done for every newly created context, then puts the task
* on the runqueue and wakes it.
*/
-void wake_up_new_task(struct task_struct *p, unsigned long clone_flags)
+void wake_up_new_task(struct task_struct *p)
{
unsigned long flags;
struct rq *rq;
- int cpu __maybe_unused = get_cpu();
+ raw_spin_lock_irqsave(&p->pi_lock, flags);
#ifdef CONFIG_SMP
- rq = task_rq_lock(p, &flags);
- p->state = TASK_WAKING;
-
/*
* Fork balancing, do it here and not earlier because:
* - cpus_allowed can change in the fork path
* - any previously selected cpu might disappear through hotplug
- *
- * We set TASK_WAKING so that select_task_rq() can drop rq->lock
- * without people poking at ->cpus_allowed.
*/
- cpu = select_task_rq(rq, p, SD_BALANCE_FORK, 0);
- set_task_cpu(p, cpu);
-
- p->state = TASK_RUNNING;
- task_rq_unlock(rq, &flags);
+ set_task_cpu(p, select_task_rq(p, SD_BALANCE_FORK, 0));
#endif
- rq = task_rq_lock(p, &flags);
+ rq = __task_rq_lock(p);
activate_task(rq, p, 0);
- trace_sched_wakeup_new(p, 1);
+ p->on_rq = 1;
+ trace_sched_wakeup_new(p, true);
check_preempt_curr(rq, p, WF_FORK);
#ifdef CONFIG_SMP
if (p->sched_class->task_woken)
p->sched_class->task_woken(rq, p);
#endif
- task_rq_unlock(rq, &flags);
- put_cpu();
+ task_rq_unlock(rq, p, &flags);
}
#ifdef CONFIG_PREEMPT_NOTIFIERS
@@ -3450,27 +3556,22 @@ void sched_exec(void)
{
struct task_struct *p = current;
unsigned long flags;
- struct rq *rq;
int dest_cpu;
- rq = task_rq_lock(p, &flags);
- dest_cpu = p->sched_class->select_task_rq(rq, p, SD_BALANCE_EXEC, 0);
+ raw_spin_lock_irqsave(&p->pi_lock, flags);
+ dest_cpu = p->sched_class->select_task_rq(p, SD_BALANCE_EXEC, 0);
if (dest_cpu == smp_processor_id())
goto unlock;
- /*
- * select_task_rq() can race against ->cpus_allowed
- */
- if (cpumask_test_cpu(dest_cpu, &p->cpus_allowed) &&
- likely(cpu_active(dest_cpu)) && migrate_task(p, rq)) {
+ if (likely(cpu_active(dest_cpu))) {
struct migration_arg arg = { p, dest_cpu };
- task_rq_unlock(rq, &flags);
- stop_one_cpu(cpu_of(rq), migration_cpu_stop, &arg);
+ raw_spin_unlock_irqrestore(&p->pi_lock, flags);
+ stop_one_cpu(task_cpu(p), migration_cpu_stop, &arg);
return;
}
unlock:
- task_rq_unlock(rq, &flags);
+ raw_spin_unlock_irqrestore(&p->pi_lock, flags);
}
#endif
@@ -3507,7 +3608,7 @@ unsigned long long task_delta_exec(struct task_struct *p)
rq = task_rq_lock(p, &flags);
ns = do_task_delta_exec(p, rq);
- task_rq_unlock(rq, &flags);
+ task_rq_unlock(rq, p, &flags);
return ns;
}
@@ -3525,7 +3626,7 @@ unsigned long long task_sched_runtime(struct task_struct *p)
rq = task_rq_lock(p, &flags);
ns = p->se.sum_exec_runtime + do_task_delta_exec(p, rq);
- task_rq_unlock(rq, &flags);
+ task_rq_unlock(rq, p, &flags);
return ns;
}
@@ -3549,7 +3650,7 @@ unsigned long long thread_group_sched_runtime(struct task_struct *p)
rq = task_rq_lock(p, &flags);
thread_group_cputime(p, &totals);
ns = totals.sum_exec_runtime + do_task_delta_exec(p, rq);
- task_rq_unlock(rq, &flags);
+ task_rq_unlock(rq, p, &flags);
return ns;
}
@@ -3903,9 +4004,6 @@ void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *st)
/*
* This function gets called by the timer code, with HZ frequency.
* We call it with interrupts disabled.
- *
- * It also gets called by the fork code, when changing the parent's
- * timeslices.
*/
void scheduler_tick(void)
{
@@ -4025,17 +4123,11 @@ static inline void schedule_debug(struct task_struct *prev)
profile_hit(SCHED_PROFILING, __builtin_return_address(0));
schedstat_inc(this_rq(), sched_count);
-#ifdef CONFIG_SCHEDSTATS
- if (unlikely(prev->lock_depth >= 0)) {
- schedstat_inc(this_rq(), rq_sched_info.bkl_count);
- schedstat_inc(prev, sched_info.bkl_count);
- }
-#endif
}
static void put_prev_task(struct rq *rq, struct task_struct *prev)
{
- if (prev->se.on_rq)
+ if (prev->on_rq || rq->skip_clock_update < 0)
update_rq_clock(rq);
prev->sched_class->put_prev_task(rq, prev);
}
@@ -4097,11 +4189,13 @@ need_resched:
if (unlikely(signal_pending_state(prev->state, prev))) {
prev->state = TASK_RUNNING;
} else {
+ deactivate_task(rq, prev, DEQUEUE_SLEEP);
+ prev->on_rq = 0;
+
/*
- * If a worker is going to sleep, notify and
- * ask workqueue whether it wants to wake up a
- * task to maintain concurrency. If so, wake
- * up the task.
+ * If a worker went to sleep, notify and ask workqueue
+ * whether it wants to wake up a task to maintain
+ * concurrency.
*/
if (prev->flags & PF_WQ_WORKER) {
struct task_struct *to_wakeup;
@@ -4110,11 +4204,10 @@ need_resched:
if (to_wakeup)
try_to_wake_up_local(to_wakeup);
}
- deactivate_task(rq, prev, DEQUEUE_SLEEP);
/*
- * If we are going to sleep and we have plugged IO queued, make
- * sure to submit it to avoid deadlocks.
+ * If we are going to sleep and we have plugged IO
+ * queued, make sure to submit it to avoid deadlocks.
*/
if (blk_needs_flush_plug(prev)) {
raw_spin_unlock(&rq->lock);
@@ -4161,70 +4254,53 @@ need_resched:
EXPORT_SYMBOL(schedule);
#ifdef CONFIG_MUTEX_SPIN_ON_OWNER
-/*
- * Look out! "owner" is an entirely speculative pointer
- * access and not reliable.
- */
-int mutex_spin_on_owner(struct mutex *lock, struct thread_info *owner)
-{
- unsigned int cpu;
- struct rq *rq;
- if (!sched_feat(OWNER_SPIN))
- return 0;
+static inline bool owner_running(struct mutex *lock, struct task_struct *owner)
+{
+ bool ret = false;
-#ifdef CONFIG_DEBUG_PAGEALLOC
- /*
- * Need to access the cpu field knowing that
- * DEBUG_PAGEALLOC could have unmapped it if
- * the mutex owner just released it and exited.
- */
- if (probe_kernel_address(&owner->cpu, cpu))
- return 0;
-#else
- cpu = owner->cpu;
-#endif
+ rcu_read_lock();
+ if (lock->owner != owner)
+ goto fail;
/*
- * Even if the access succeeded (likely case),
- * the cpu field may no longer be valid.
+ * Ensure we emit the owner->on_cpu, dereference _after_ checking
+ * lock->owner still matches owner, if that fails, owner might
+ * point to free()d memory, if it still matches, the rcu_read_lock()
+ * ensures the memory stays valid.
*/
- if (cpu >= nr_cpumask_bits)
- return 0;
+ barrier();
- /*
- * We need to validate that we can do a
- * get_cpu() and that we have the percpu area.
- */
- if (!cpu_online(cpu))
- return 0;
+ ret = owner->on_cpu;
+fail:
+ rcu_read_unlock();
- rq = cpu_rq(cpu);
+ return ret;
+}
- for (;;) {
- /*
- * Owner changed, break to re-assess state.
- */
- if (lock->owner != owner) {
- /*
- * If the lock has switched to a different owner,
- * we likely have heavy contention. Return 0 to quit
- * optimistic spinning and not contend further:
- */
- if (lock->owner)
- return 0;
- break;
- }
+/*
+ * Look out! "owner" is an entirely speculative pointer
+ * access and not reliable.
+ */
+int mutex_spin_on_owner(struct mutex *lock, struct task_struct *owner)
+{
+ if (!sched_feat(OWNER_SPIN))
+ return 0;
- /*
- * Is that owner really running on that cpu?
- */
- if (task_thread_info(rq->curr) != owner || need_resched())
+ while (owner_running(lock, owner)) {
+ if (need_resched())
return 0;
arch_mutex_cpu_relax();
}
+ /*
+ * If the owner changed to another task there is likely
+ * heavy contention, stop spinning.
+ */
+ if (lock->owner)
+ return 0;
+
return 1;
}
#endif
@@ -4684,19 +4760,18 @@ EXPORT_SYMBOL(sleep_on_timeout);
*/
void rt_mutex_setprio(struct task_struct *p, int prio)
{
- unsigned long flags;
int oldprio, on_rq, running;
struct rq *rq;
const struct sched_class *prev_class;
BUG_ON(prio < 0 || prio > MAX_PRIO);
- rq = task_rq_lock(p, &flags);
+ rq = __task_rq_lock(p);
trace_sched_pi_setprio(p, prio);
oldprio = p->prio;
prev_class = p->sched_class;
- on_rq = p->se.on_rq;
+ on_rq = p->on_rq;
running = task_current(rq, p);
if (on_rq)
dequeue_task(rq, p, 0);
@@ -4716,7 +4791,7 @@ void rt_mutex_setprio(struct task_struct *p, int prio)
enqueue_task(rq, p, oldprio < prio ? ENQUEUE_HEAD : 0);
check_class_changed(rq, p, prev_class, oldprio);
- task_rq_unlock(rq, &flags);
+ __task_rq_unlock(rq);
}
#endif
@@ -4744,7 +4819,7 @@ void set_user_nice(struct task_struct *p, long nice)
p->static_prio = NICE_TO_PRIO(nice);
goto out_unlock;
}
- on_rq = p->se.on_rq;
+ on_rq = p->on_rq;
if (on_rq)
dequeue_task(rq, p, 0);
@@ -4764,7 +4839,7 @@ void set_user_nice(struct task_struct *p, long nice)
resched_task(rq->curr);
}
out_unlock:
- task_rq_unlock(rq, &flags);
+ task_rq_unlock(rq, p, &flags);
}
EXPORT_SYMBOL(set_user_nice);
@@ -4878,8 +4953,6 @@ static struct task_struct *find_process_by_pid(pid_t pid)
static void
__setscheduler(struct rq *rq, struct task_struct *p, int policy, int prio)
{
- BUG_ON(p->se.on_rq);
-
p->policy = policy;
p->rt_priority = prio;
p->normal_prio = normal_prio(p);
@@ -4994,20 +5067,17 @@ recheck:
/*
* make sure no PI-waiters arrive (or leave) while we are
* changing the priority of the task:
- */
- raw_spin_lock_irqsave(&p->pi_lock, flags);
- /*
+ *
* To be able to change p->policy safely, the appropriate
* runqueue lock must be held.
*/
- rq = __task_rq_lock(p);
+ rq = task_rq_lock(p, &flags);
/*
* Changing the policy of the stop threads its a very bad idea
*/
if (p == rq->stop) {
- __task_rq_unlock(rq);
- raw_spin_unlock_irqrestore(&p->pi_lock, flags);
+ task_rq_unlock(rq, p, &flags);
return -EINVAL;
}
@@ -5031,8 +5101,7 @@ recheck:
if (rt_bandwidth_enabled() && rt_policy(policy) &&
task_group(p)->rt_bandwidth.rt_runtime == 0 &&
!task_group_is_autogroup(task_group(p))) {
- __task_rq_unlock(rq);
- raw_spin_unlock_irqrestore(&p->pi_lock, flags);
+ task_rq_unlock(rq, p, &flags);
return -EPERM;
}
}
@@ -5041,11 +5110,10 @@ recheck:
/* recheck policy now with rq lock held */
if (unlikely(oldpolicy != -1 && oldpolicy != p->policy)) {
policy = oldpolicy = -1;
- __task_rq_unlock(rq);
- raw_spin_unlock_irqrestore(&p->pi_lock, flags);
+ task_rq_unlock(rq, p, &flags);
goto recheck;
}
- on_rq = p->se.on_rq;
+ on_rq = p->on_rq;
running = task_current(rq, p);
if (on_rq)
deactivate_task(rq, p, 0);
@@ -5064,8 +5132,7 @@ recheck:
activate_task(rq, p, 0);
check_class_changed(rq, p, prev_class, oldprio);
- __task_rq_unlock(rq);
- raw_spin_unlock_irqrestore(&p->pi_lock, flags);
+ task_rq_unlock(rq, p, &flags);
rt_mutex_adjust_pi(p);
@@ -5316,7 +5383,6 @@ long sched_getaffinity(pid_t pid, struct cpumask *mask)
{
struct task_struct *p;
unsigned long flags;
- struct rq *rq;
int retval;
get_online_cpus();
@@ -5331,9 +5397,9 @@ long sched_getaffinity(pid_t pid, struct cpumask *mask)
if (retval)
goto out_unlock;
- rq = task_rq_lock(p, &flags);
+ raw_spin_lock_irqsave(&p->pi_lock, flags);
cpumask_and(mask, &p->cpus_allowed, cpu_online_mask);
- task_rq_unlock(rq, &flags);
+ raw_spin_unlock_irqrestore(&p->pi_lock, flags);
out_unlock:
rcu_read_unlock();
@@ -5658,7 +5724,7 @@ SYSCALL_DEFINE2(sched_rr_get_interval, pid_t, pid,
rq = task_rq_lock(p, &flags);
time_slice = p->sched_class->get_rr_interval(rq, p);
- task_rq_unlock(rq, &flags);
+ task_rq_unlock(rq, p, &flags);
rcu_read_unlock();
jiffies_to_timespec(time_slice, &t);
@@ -5776,17 +5842,14 @@ void __cpuinit init_idle(struct task_struct *idle, int cpu)
rcu_read_unlock();
rq->curr = rq->idle = idle;
-#if defined(CONFIG_SMP) && defined(__ARCH_WANT_UNLOCKED_CTXSW)
- idle->oncpu = 1;
+#if defined(CONFIG_SMP)
+ idle->on_cpu = 1;
#endif
raw_spin_unlock_irqrestore(&rq->lock, flags);
/* Set the preempt count _outside_ the spinlocks! */
-#if defined(CONFIG_PREEMPT)
- task_thread_info(idle)->preempt_count = (idle->lock_depth >= 0);
-#else
task_thread_info(idle)->preempt_count = 0;
-#endif
+
/*
* The idle tasks have their own, simple scheduling class:
*/
@@ -5881,26 +5944,17 @@ int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
unsigned int dest_cpu;
int ret = 0;
- /*
- * Serialize against TASK_WAKING so that ttwu() and wunt() can
- * drop the rq->lock and still rely on ->cpus_allowed.
- */
-again:
- while (task_is_waking(p))
- cpu_relax();
rq = task_rq_lock(p, &flags);
- if (task_is_waking(p)) {
- task_rq_unlock(rq, &flags);
- goto again;
- }
+
+ if (cpumask_equal(&p->cpus_allowed, new_mask))
+ goto out;
if (!cpumask_intersects(new_mask, cpu_active_mask)) {
ret = -EINVAL;
goto out;
}
- if (unlikely((p->flags & PF_THREAD_BOUND) && p != current &&
- !cpumask_equal(&p->cpus_allowed, new_mask))) {
+ if (unlikely((p->flags & PF_THREAD_BOUND) && p != current)) {
ret = -EINVAL;
goto out;
}
@@ -5917,16 +5971,16 @@ again:
goto out;
dest_cpu = cpumask_any_and(cpu_active_mask, new_mask);
- if (migrate_task(p, rq)) {
+ if (p->on_rq) {
struct migration_arg arg = { p, dest_cpu };
/* Need help from migration thread: drop lock and wait. */
- task_rq_unlock(rq, &flags);
+ task_rq_unlock(rq, p, &flags);
stop_one_cpu(cpu_of(rq), migration_cpu_stop, &arg);
tlb_migrate_finish(p->mm);
return 0;
}
out:
- task_rq_unlock(rq, &flags);
+ task_rq_unlock(rq, p, &flags);
return ret;
}
@@ -5954,6 +6008,7 @@ static int __migrate_task(struct task_struct *p, int src_cpu, int dest_cpu)
rq_src = cpu_rq(src_cpu);
rq_dest = cpu_rq(dest_cpu);
+ raw_spin_lock(&p->pi_lock);
double_rq_lock(rq_src, rq_dest);
/* Already moved. */
if (task_cpu(p) != src_cpu)
@@ -5966,7 +6021,7 @@ static int __migrate_task(struct task_struct *p, int src_cpu, int dest_cpu)
* If we're not on a rq, the next wake-up will ensure we're
* placed properly.
*/
- if (p->se.on_rq) {
+ if (p->on_rq) {
deactivate_task(rq_src, p, 0);
set_task_cpu(p, dest_cpu);
activate_task(rq_dest, p, 0);
@@ -5976,6 +6031,7 @@ done:
ret = 1;
fail:
double_rq_unlock(rq_src, rq_dest);
+ raw_spin_unlock(&p->pi_lock);
return ret;
}
@@ -6316,6 +6372,7 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
#ifdef CONFIG_HOTPLUG_CPU
case CPU_DYING:
+ sched_ttwu_pending();
/* Update our root-domain */
raw_spin_lock_irqsave(&rq->lock, flags);
if (rq->rd) {
@@ -6394,6 +6451,8 @@ early_initcall(migration_init);
#ifdef CONFIG_SMP
+static cpumask_var_t sched_domains_tmpmask; /* sched_domains_mutex */
+
#ifdef CONFIG_SCHED_DEBUG
static __read_mostly int sched_domain_debug_enabled;
@@ -6489,7 +6548,6 @@ static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level,
static void sched_domain_debug(struct sched_domain *sd, int cpu)
{
- cpumask_var_t groupmask;
int level = 0;
if (!sched_domain_debug_enabled)
@@ -6502,20 +6560,14 @@ static void sched_domain_debug(struct sched_domain *sd, int cpu)
printk(KERN_DEBUG "CPU%d attaching sched-domain:\n", cpu);
- if (!alloc_cpumask_var(&groupmask, GFP_KERNEL)) {
- printk(KERN_DEBUG "Cannot load-balance (out of memory)\n");
- return;
- }
-
for (;;) {
- if (sched_domain_debug_one(sd, cpu, level, groupmask))
+ if (sched_domain_debug_one(sd, cpu, level, sched_domains_tmpmask))
break;
level++;
sd = sd->parent;
if (!sd)
break;
}
- free_cpumask_var(groupmask);
}
#else /* !CONFIG_SCHED_DEBUG */
# define sched_domain_debug(sd, cpu) do { } while (0)
@@ -6572,12 +6624,11 @@ sd_parent_degenerate(struct sched_domain *sd, struct sched_domain *parent)
return 1;
}
-static void free_rootdomain(struct root_domain *rd)
+static void free_rootdomain(struct rcu_head *rcu)
{
- synchronize_sched();
+ struct root_domain *rd = container_of(rcu, struct root_domain, rcu);
cpupri_cleanup(&rd->cpupri);
-
free_cpumask_var(rd->rto_mask);
free_cpumask_var(rd->online);
free_cpumask_var(rd->span);
@@ -6618,7 +6669,7 @@ static void rq_attach_root(struct rq *rq, struct root_domain *rd)
raw_spin_unlock_irqrestore(&rq->lock, flags);
if (old_rd)
- free_rootdomain(old_rd);
+ call_rcu_sched(&old_rd->rcu, free_rootdomain);
}
static int init_rootdomain(struct root_domain *rd)
@@ -6669,6 +6720,25 @@ static struct root_domain *alloc_rootdomain(void)
return rd;
}
+static void free_sched_domain(struct rcu_head *rcu)
+{
+ struct sched_domain *sd = container_of(rcu, struct sched_domain, rcu);
+ if (atomic_dec_and_test(&sd->groups->ref))
+ kfree(sd->groups);
+ kfree(sd);
+}
+
+static void destroy_sched_domain(struct sched_domain *sd, int cpu)
+{
+ call_rcu(&sd->rcu, free_sched_domain);
+}
+
+static void destroy_sched_domains(struct sched_domain *sd, int cpu)
+{
+ for (; sd; sd = sd->parent)
+ destroy_sched_domain(sd, cpu);
+}
+
/*
* Attach the domain 'sd' to 'cpu' as its base domain. Callers must
* hold the hotplug lock.
@@ -6679,9 +6749,6 @@ cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu)
struct rq *rq = cpu_rq(cpu);
struct sched_domain *tmp;
- for (tmp = sd; tmp; tmp = tmp->parent)
- tmp->span_weight = cpumask_weight(sched_domain_span(tmp));
-
/* Remove the sched domains which do not contribute to scheduling. */
for (tmp = sd; tmp; ) {
struct sched_domain *parent = tmp->parent;
@@ -6692,12 +6759,15 @@ cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu)
tmp->parent = parent->parent;
if (parent->parent)
parent->parent->child = tmp;
+ destroy_sched_domain(parent, cpu);
} else
tmp = tmp->parent;
}
if (sd && sd_degenerate(sd)) {
+ tmp = sd;
sd = sd->parent;
+ destroy_sched_domain(tmp, cpu);
if (sd)
sd->child = NULL;
}
@@ -6705,7 +6775,9 @@ cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu)
sched_domain_debug(sd, cpu);
rq_attach_root(rq, rd);
+ tmp = rq->sd;
rcu_assign_pointer(rq->sd, sd);
+ destroy_sched_domains(tmp, cpu);
}
/* cpus with isolated domains */
@@ -6721,56 +6793,6 @@ static int __init isolated_cpu_setup(char *str)
__setup("isolcpus=", isolated_cpu_setup);
-/*
- * init_sched_build_groups takes the cpumask we wish to span, and a pointer
- * to a function which identifies what group(along with sched group) a CPU
- * belongs to. The return value of group_fn must be a >= 0 and < nr_cpu_ids
- * (due to the fact that we keep track of groups covered with a struct cpumask).
- *
- * init_sched_build_groups will build a circular linked list of the groups
- * covered by the given span, and will set each group's ->cpumask correctly,
- * and ->cpu_power to 0.
- */
-static void
-init_sched_build_groups(const struct cpumask *span,
- const struct cpumask *cpu_map,
- int (*group_fn)(int cpu, const struct cpumask *cpu_map,
- struct sched_group **sg,
- struct cpumask *tmpmask),
- struct cpumask *covered, struct cpumask *tmpmask)
-{
- struct sched_group *first = NULL, *last = NULL;
- int i;
-
- cpumask_clear(covered);
-
- for_each_cpu(i, span) {
- struct sched_group *sg;
- int group = group_fn(i, cpu_map, &sg, tmpmask);
- int j;
-
- if (cpumask_test_cpu(i, covered))
- continue;
-
- cpumask_clear(sched_group_cpus(sg));
- sg->cpu_power = 0;
-
- for_each_cpu(j, span) {
- if (group_fn(j, cpu_map, NULL, tmpmask) != group)
- continue;
-
- cpumask_set_cpu(j, covered);
- cpumask_set_cpu(j, sched_group_cpus(sg));
- }
- if (!first)
- first = sg;
- if (last)
- last->next = sg;
- last = sg;
- }
- last->next = first;
-}
-
#define SD_NODES_PER_DOMAIN 16
#ifdef CONFIG_NUMA
@@ -6787,7 +6809,7 @@ init_sched_build_groups(const struct cpumask *span,
*/
static int find_next_best_node(int node, nodemask_t *used_nodes)
{
- int i, n, val, min_val, best_node = 0;
+ int i, n, val, min_val, best_node = -1;
min_val = INT_MAX;
@@ -6811,7 +6833,8 @@ static int find_next_best_node(int node, nodemask_t *used_nodes)
}
}
- node_set(best_node, *used_nodes);
+ if (best_node != -1)
+ node_set(best_node, *used_nodes);
return best_node;
}
@@ -6837,315 +6860,130 @@ static void sched_domain_node_span(int node, struct cpumask *span)
for (i = 1; i < SD_NODES_PER_DOMAIN; i++) {
int next_node = find_next_best_node(node, &used_nodes);
-
+ if (next_node < 0)
+ break;
cpumask_or(span, span, cpumask_of_node(next_node));
}
}
+
+static const struct cpumask *cpu_node_mask(int cpu)
+{
+ lockdep_assert_held(&sched_domains_mutex);
+
+ sched_domain_node_span(cpu_to_node(cpu), sched_domains_tmpmask);
+
+ return sched_domains_tmpmask;
+}
+
+static const struct cpumask *cpu_allnodes_mask(int cpu)
+{
+ return cpu_possible_mask;
+}
#endif /* CONFIG_NUMA */
-int sched_smt_power_savings = 0, sched_mc_power_savings = 0;
+static const struct cpumask *cpu_cpu_mask(int cpu)
+{
+ return cpumask_of_node(cpu_to_node(cpu));
+}
-/*
- * The cpus mask in sched_group and sched_domain hangs off the end.
- *
- * ( See the the comments in include/linux/sched.h:struct sched_group
- * and struct sched_domain. )
- */
-struct static_sched_group {
- struct sched_group sg;
- DECLARE_BITMAP(cpus, CONFIG_NR_CPUS);
-};
+int sched_smt_power_savings = 0, sched_mc_power_savings = 0;
-struct static_sched_domain {
- struct sched_domain sd;
- DECLARE_BITMAP(span, CONFIG_NR_CPUS);
+struct sd_data {
+ struct sched_domain **__percpu sd;
+ struct sched_group **__percpu sg;
};
struct s_data {
-#ifdef CONFIG_NUMA
- int sd_allnodes;
- cpumask_var_t domainspan;
- cpumask_var_t covered;
- cpumask_var_t notcovered;
-#endif
- cpumask_var_t nodemask;
- cpumask_var_t this_sibling_map;
- cpumask_var_t this_core_map;
- cpumask_var_t this_book_map;
- cpumask_var_t send_covered;
- cpumask_var_t tmpmask;
- struct sched_group **sched_group_nodes;
+ struct sched_domain ** __percpu sd;
struct root_domain *rd;
};
enum s_alloc {
- sa_sched_groups = 0,
sa_rootdomain,
- sa_tmpmask,
- sa_send_covered,
- sa_this_book_map,
- sa_this_core_map,
- sa_this_sibling_map,
- sa_nodemask,
- sa_sched_group_nodes,
-#ifdef CONFIG_NUMA
- sa_notcovered,
- sa_covered,
- sa_domainspan,
-#endif
+ sa_sd,
+ sa_sd_storage,
sa_none,
};
-/*
- * SMT sched-domains:
- */
-#ifdef CONFIG_SCHED_SMT
-static DEFINE_PER_CPU(struct static_sched_domain, cpu_domains);
-static DEFINE_PER_CPU(struct static_sched_group, sched_groups);
+struct sched_domain_topology_level;
-static int
-cpu_to_cpu_group(int cpu, const struct cpumask *cpu_map,
- struct sched_group **sg, struct cpumask *unused)
-{
- if (sg)
- *sg = &per_cpu(sched_groups, cpu).sg;
- return cpu;
-}
-#endif /* CONFIG_SCHED_SMT */
+typedef struct sched_domain *(*sched_domain_init_f)(struct sched_domain_topology_level *tl, int cpu);
+typedef const struct cpumask *(*sched_domain_mask_f)(int cpu);
-/*
- * multi-core sched-domains:
- */
-#ifdef CONFIG_SCHED_MC
-static DEFINE_PER_CPU(struct static_sched_domain, core_domains);
-static DEFINE_PER_CPU(struct static_sched_group, sched_group_core);
-
-static int
-cpu_to_core_group(int cpu, const struct cpumask *cpu_map,
- struct sched_group **sg, struct cpumask *mask)
-{
- int group;
-#ifdef CONFIG_SCHED_SMT
- cpumask_and(mask, topology_thread_cpumask(cpu), cpu_map);
- group = cpumask_first(mask);
-#else
- group = cpu;
-#endif
- if (sg)
- *sg = &per_cpu(sched_group_core, group).sg;
- return group;
-}
-#endif /* CONFIG_SCHED_MC */
+struct sched_domain_topology_level {
+ sched_domain_init_f init;
+ sched_domain_mask_f mask;
+ struct sd_data data;
+};
/*
- * book sched-domains:
+ * Assumes the sched_domain tree is fully constructed
*/
-#ifdef CONFIG_SCHED_BOOK
-static DEFINE_PER_CPU(struct static_sched_domain, book_domains);
-static DEFINE_PER_CPU(struct static_sched_group, sched_group_book);
-
-static int
-cpu_to_book_group(int cpu, const struct cpumask *cpu_map,
- struct sched_group **sg, struct cpumask *mask)
+static int get_group(int cpu, struct sd_data *sdd, struct sched_group **sg)
{
- int group = cpu;
-#ifdef CONFIG_SCHED_MC
- cpumask_and(mask, cpu_coregroup_mask(cpu), cpu_map);
- group = cpumask_first(mask);
-#elif defined(CONFIG_SCHED_SMT)
- cpumask_and(mask, topology_thread_cpumask(cpu), cpu_map);
- group = cpumask_first(mask);
-#endif
- if (sg)
- *sg = &per_cpu(sched_group_book, group).sg;
- return group;
-}
-#endif /* CONFIG_SCHED_BOOK */
+ struct sched_domain *sd = *per_cpu_ptr(sdd->sd, cpu);
+ struct sched_domain *child = sd->child;
-static DEFINE_PER_CPU(struct static_sched_domain, phys_domains);
-static DEFINE_PER_CPU(struct static_sched_group, sched_group_phys);
+ if (child)
+ cpu = cpumask_first(sched_domain_span(child));
-static int
-cpu_to_phys_group(int cpu, const struct cpumask *cpu_map,
- struct sched_group **sg, struct cpumask *mask)
-{
- int group;
-#ifdef CONFIG_SCHED_BOOK
- cpumask_and(mask, cpu_book_mask(cpu), cpu_map);
- group = cpumask_first(mask);
-#elif defined(CONFIG_SCHED_MC)
- cpumask_and(mask, cpu_coregroup_mask(cpu), cpu_map);
- group = cpumask_first(mask);
-#elif defined(CONFIG_SCHED_SMT)
- cpumask_and(mask, topology_thread_cpumask(cpu), cpu_map);
- group = cpumask_first(mask);
-#else
- group = cpu;
-#endif
if (sg)
- *sg = &per_cpu(sched_group_phys, group).sg;
- return group;
+ *sg = *per_cpu_ptr(sdd->sg, cpu);
+
+ return cpu;
}
-#ifdef CONFIG_NUMA
/*
- * The init_sched_build_groups can't handle what we want to do with node
- * groups, so roll our own. Now each node has its own list of groups which
- * gets dynamically allocated.
+ * build_sched_groups takes the cpumask we wish to span, and a pointer
+ * to a function which identifies what group(along with sched group) a CPU
+ * belongs to. The return value of group_fn must be a >= 0 and < nr_cpu_ids
+ * (due to the fact that we keep track of groups covered with a struct cpumask).
+ *
+ * build_sched_groups will build a circular linked list of the groups
+ * covered by the given span, and will set each group's ->cpumask correctly,
+ * and ->cpu_power to 0.
*/
-static DEFINE_PER_CPU(struct static_sched_domain, node_domains);
-static struct sched_group ***sched_group_nodes_bycpu;
-
-static DEFINE_PER_CPU(struct static_sched_domain, allnodes_domains);
-static DEFINE_PER_CPU(struct static_sched_group, sched_group_allnodes);
-
-static int cpu_to_allnodes_group(int cpu, const struct cpumask *cpu_map,
- struct sched_group **sg,
- struct cpumask *nodemask)
-{
- int group;
-
- cpumask_and(nodemask, cpumask_of_node(cpu_to_node(cpu)), cpu_map);
- group = cpumask_first(nodemask);
-
- if (sg)
- *sg = &per_cpu(sched_group_allnodes, group).sg;
- return group;
-}
-
-static void init_numa_sched_groups_power(struct sched_group *group_head)
-{
- struct sched_group *sg = group_head;
- int j;
-
- if (!sg)
- return;
- do {
- for_each_cpu(j, sched_group_cpus(sg)) {
- struct sched_domain *sd;
-
- sd = &per_cpu(phys_domains, j).sd;
- if (j != group_first_cpu(sd->groups)) {
- /*
- * Only add "power" once for each
- * physical package.
- */
- continue;
- }
-
- sg->cpu_power += sd->groups->cpu_power;
- }
- sg = sg->next;
- } while (sg != group_head);
-}
-
-static int build_numa_sched_groups(struct s_data *d,
- const struct cpumask *cpu_map, int num)
+static void
+build_sched_groups(struct sched_domain *sd)
{
- struct sched_domain *sd;
- struct sched_group *sg, *prev;
- int n, j;
-
- cpumask_clear(d->covered);
- cpumask_and(d->nodemask, cpumask_of_node(num), cpu_map);
- if (cpumask_empty(d->nodemask)) {
- d->sched_group_nodes[num] = NULL;
- goto out;
- }
-
- sched_domain_node_span(num, d->domainspan);
- cpumask_and(d->domainspan, d->domainspan, cpu_map);
-
- sg = kmalloc_node(sizeof(struct sched_group) + cpumask_size(),
- GFP_KERNEL, num);
- if (!sg) {
- printk(KERN_WARNING "Can not alloc domain group for node %d\n",
- num);
- return -ENOMEM;
- }
- d->sched_group_nodes[num] = sg;
-
- for_each_cpu(j, d->nodemask) {
- sd = &per_cpu(node_domains, j).sd;
- sd->groups = sg;
- }
-
- sg->cpu_power = 0;
- cpumask_copy(sched_group_cpus(sg), d->nodemask);
- sg->next = sg;
- cpumask_or(d->covered, d->covered, d->nodemask);
+ struct sched_group *first = NULL, *last = NULL;
+ struct sd_data *sdd = sd->private;
+ const struct cpumask *span = sched_domain_span(sd);
+ struct cpumask *covered;
+ int i;
- prev = sg;
- for (j = 0; j < nr_node_ids; j++) {
- n = (num + j) % nr_node_ids;
- cpumask_complement(d->notcovered, d->covered);
- cpumask_and(d->tmpmask, d->notcovered, cpu_map);
- cpumask_and(d->tmpmask, d->tmpmask, d->domainspan);
- if (cpumask_empty(d->tmpmask))
- break;
- cpumask_and(d->tmpmask, d->tmpmask, cpumask_of_node(n));
- if (cpumask_empty(d->tmpmask))
- continue;
- sg = kmalloc_node(sizeof(struct sched_group) + cpumask_size(),
- GFP_KERNEL, num);
- if (!sg) {
- printk(KERN_WARNING
- "Can not alloc domain group for node %d\n", j);
- return -ENOMEM;
- }
- sg->cpu_power = 0;
- cpumask_copy(sched_group_cpus(sg), d->tmpmask);
- sg->next = prev->next;
- cpumask_or(d->covered, d->covered, d->tmpmask);
- prev->next = sg;
- prev = sg;
- }
-out:
- return 0;
-}
-#endif /* CONFIG_NUMA */
+ lockdep_assert_held(&sched_domains_mutex);
+ covered = sched_domains_tmpmask;
-#ifdef CONFIG_NUMA
-/* Free memory allocated for various sched_group structures */
-static void free_sched_groups(const struct cpumask *cpu_map,
- struct cpumask *nodemask)
-{
- int cpu, i;
+ cpumask_clear(covered);
- for_each_cpu(cpu, cpu_map) {
- struct sched_group **sched_group_nodes
- = sched_group_nodes_bycpu[cpu];
+ for_each_cpu(i, span) {
+ struct sched_group *sg;
+ int group = get_group(i, sdd, &sg);
+ int j;
- if (!sched_group_nodes)
+ if (cpumask_test_cpu(i, covered))
continue;
- for (i = 0; i < nr_node_ids; i++) {
- struct sched_group *oldsg, *sg = sched_group_nodes[i];
+ cpumask_clear(sched_group_cpus(sg));
+ sg->cpu_power = 0;
- cpumask_and(nodemask, cpumask_of_node(i), cpu_map);
- if (cpumask_empty(nodemask))
+ for_each_cpu(j, span) {
+ if (get_group(j, sdd, NULL) != group)
continue;
- if (sg == NULL)
- continue;
- sg = sg->next;
-next_sg:
- oldsg = sg;
- sg = sg->next;
- kfree(oldsg);
- if (oldsg != sched_group_nodes[i])
- goto next_sg;
+ cpumask_set_cpu(j, covered);
+ cpumask_set_cpu(j, sched_group_cpus(sg));
}
- kfree(sched_group_nodes);
- sched_group_nodes_bycpu[cpu] = NULL;
+
+ if (!first)
+ first = sg;
+ if (last)
+ last->next = sg;
+ last = sg;
}
+ last->next = first;
}
-#else /* !CONFIG_NUMA */
-static void free_sched_groups(const struct cpumask *cpu_map,
- struct cpumask *nodemask)
-{
-}
-#endif /* CONFIG_NUMA */
/*
* Initialize sched groups cpu_power.
@@ -7159,11 +6997,6 @@ static void free_sched_groups(const struct cpumask *cpu_map,
*/
static void init_sched_groups_power(int cpu, struct sched_domain *sd)
{
- struct sched_domain *child;
- struct sched_group *group;
- long power;
- int weight;
-
WARN_ON(!sd || !sd->groups);
if (cpu != group_first_cpu(sd->groups))
@@ -7171,36 +7004,7 @@ static void init_sched_groups_power(int cpu, struct sched_domain *sd)
sd->groups->group_weight = cpumask_weight(sched_group_cpus(sd->groups));
- child = sd->child;
-
- sd->groups->cpu_power = 0;
-
- if (!child) {
- power = SCHED_LOAD_SCALE;
- weight = cpumask_weight(sched_domain_span(sd));
- /*
- * SMT siblings share the power of a single core.
- * Usually multiple threads get a better yield out of
- * that one core than a single thread would have,
- * reflect that in sd->smt_gain.
- */
- if ((sd->flags & SD_SHARE_CPUPOWER) && weight > 1) {
- power *= sd->smt_gain;
- power /= weight;
- power >>= SCHED_LOAD_SHIFT;
- }
- sd->groups->cpu_power += power;
- return;
- }
-
- /*
- * Add cpu_power of each child group to this groups cpu_power.
- */
- group = child->groups;
- do {
- sd->groups->cpu_power += group->cpu_power;
- group = group->next;
- } while (group != child->groups);
+ update_group_power(sd, cpu);
}
/*
@@ -7214,15 +7018,15 @@ static void init_sched_groups_power(int cpu, struct sched_domain *sd)
# define SD_INIT_NAME(sd, type) do { } while (0)
#endif
-#define SD_INIT(sd, type) sd_init_##type(sd)
-
-#define SD_INIT_FUNC(type) \
-static noinline void sd_init_##type(struct sched_domain *sd) \
-{ \
- memset(sd, 0, sizeof(*sd)); \
- *sd = SD_##type##_INIT; \
- sd->level = SD_LV_##type; \
- SD_INIT_NAME(sd, type); \
+#define SD_INIT_FUNC(type) \
+static noinline struct sched_domain * \
+sd_init_##type(struct sched_domain_topology_level *tl, int cpu) \
+{ \
+ struct sched_domain *sd = *per_cpu_ptr(tl->data.sd, cpu); \
+ *sd = SD_##type##_INIT; \
+ SD_INIT_NAME(sd, type); \
+ sd->private = &tl->data; \
+ return sd; \
}
SD_INIT_FUNC(CPU)
@@ -7241,13 +7045,14 @@ SD_INIT_FUNC(CPU)
#endif
static int default_relax_domain_level = -1;
+int sched_domain_level_max;
static int __init setup_relax_domain_level(char *str)
{
unsigned long val;
val = simple_strtoul(str, NULL, 0);
- if (val < SD_LV_MAX)
+ if (val < sched_domain_level_max)
default_relax_domain_level = val;
return 1;
@@ -7275,37 +7080,20 @@ static void set_domain_attribute(struct sched_domain *sd,
}
}
+static void __sdt_free(const struct cpumask *cpu_map);
+static int __sdt_alloc(const struct cpumask *cpu_map);
+
static void __free_domain_allocs(struct s_data *d, enum s_alloc what,
const struct cpumask *cpu_map)
{
switch (what) {
- case sa_sched_groups:
- free_sched_groups(cpu_map, d->tmpmask); /* fall through */
- d->sched_group_nodes = NULL;
case sa_rootdomain:
- free_rootdomain(d->rd); /* fall through */
- case sa_tmpmask:
- free_cpumask_var(d->tmpmask); /* fall through */
- case sa_send_covered:
- free_cpumask_var(d->send_covered); /* fall through */
- case sa_this_book_map:
- free_cpumask_var(d->this_book_map); /* fall through */
- case sa_this_core_map:
- free_cpumask_var(d->this_core_map); /* fall through */
- case sa_this_sibling_map:
- free_cpumask_var(d->this_sibling_map); /* fall through */
- case sa_nodemask:
- free_cpumask_var(d->nodemask); /* fall through */
- case sa_sched_group_nodes:
-#ifdef CONFIG_NUMA
- kfree(d->sched_group_nodes); /* fall through */
- case sa_notcovered:
- free_cpumask_var(d->notcovered); /* fall through */
- case sa_covered:
- free_cpumask_var(d->covered); /* fall through */
- case sa_domainspan:
- free_cpumask_var(d->domainspan); /* fall through */
-#endif
+ if (!atomic_read(&d->rd->refcount))
+ free_rootdomain(&d->rd->rcu); /* fall through */
+ case sa_sd:
+ free_percpu(d->sd); /* fall through */
+ case sa_sd_storage:
+ __sdt_free(cpu_map); /* fall through */
case sa_none:
break;
}
@@ -7314,308 +7102,212 @@ static void __free_domain_allocs(struct s_data *d, enum s_alloc what,
static enum s_alloc __visit_domain_allocation_hell(struct s_data *d,
const struct cpumask *cpu_map)
{
-#ifdef CONFIG_NUMA
- if (!alloc_cpumask_var(&d->domainspan, GFP_KERNEL))
- return sa_none;
- if (!alloc_cpumask_var(&d->covered, GFP_KERNEL))
- return sa_domainspan;
- if (!alloc_cpumask_var(&d->notcovered, GFP_KERNEL))
- return sa_covered;
- /* Allocate the per-node list of sched groups */
- d->sched_group_nodes = kcalloc(nr_node_ids,
- sizeof(struct sched_group *), GFP_KERNEL);
- if (!d->sched_group_nodes) {
- printk(KERN_WARNING "Can not alloc sched group node list\n");
- return sa_notcovered;
- }
- sched_group_nodes_bycpu[cpumask_first(cpu_map)] = d->sched_group_nodes;
-#endif
- if (!alloc_cpumask_var(&d->nodemask, GFP_KERNEL))
- return sa_sched_group_nodes;
- if (!alloc_cpumask_var(&d->this_sibling_map, GFP_KERNEL))
- return sa_nodemask;
- if (!alloc_cpumask_var(&d->this_core_map, GFP_KERNEL))
- return sa_this_sibling_map;
- if (!alloc_cpumask_var(&d->this_book_map, GFP_KERNEL))
- return sa_this_core_map;
- if (!alloc_cpumask_var(&d->send_covered, GFP_KERNEL))
- return sa_this_book_map;
- if (!alloc_cpumask_var(&d->tmpmask, GFP_KERNEL))
- return sa_send_covered;
+ memset(d, 0, sizeof(*d));
+
+ if (__sdt_alloc(cpu_map))
+ return sa_sd_storage;
+ d->sd = alloc_percpu(struct sched_domain *);
+ if (!d->sd)
+ return sa_sd_storage;
d->rd = alloc_rootdomain();
- if (!d->rd) {
- printk(KERN_WARNING "Cannot alloc root domain\n");
- return sa_tmpmask;
- }
+ if (!d->rd)
+ return sa_sd;
return sa_rootdomain;
}
-static struct sched_domain *__build_numa_sched_domains(struct s_data *d,
- const struct cpumask *cpu_map, struct sched_domain_attr *attr, int i)
+/*
+ * NULL the sd_data elements we've used to build the sched_domain and
+ * sched_group structure so that the subsequent __free_domain_allocs()
+ * will not free the data we're using.
+ */
+static void claim_allocations(int cpu, struct sched_domain *sd)
{
- struct sched_domain *sd = NULL;
-#ifdef CONFIG_NUMA
- struct sched_domain *parent;
-
- d->sd_allnodes = 0;
- if (cpumask_weight(cpu_map) >
- SD_NODES_PER_DOMAIN * cpumask_weight(d->nodemask)) {
- sd = &per_cpu(allnodes_domains, i).sd;
- SD_INIT(sd, ALLNODES);
- set_domain_attribute(sd, attr);
- cpumask_copy(sched_domain_span(sd), cpu_map);
- cpu_to_allnodes_group(i, cpu_map, &sd->groups, d->tmpmask);
- d->sd_allnodes = 1;
- }
- parent = sd;
-
- sd = &per_cpu(node_domains, i).sd;
- SD_INIT(sd, NODE);
- set_domain_attribute(sd, attr);
- sched_domain_node_span(cpu_to_node(i), sched_domain_span(sd));
- sd->parent = parent;
- if (parent)
- parent->child = sd;
- cpumask_and(sched_domain_span(sd), sched_domain_span(sd), cpu_map);
-#endif
- return sd;
-}
+ struct sd_data *sdd = sd->private;
+ struct sched_group *sg = sd->groups;
-static struct sched_domain *__build_cpu_sched_domain(struct s_data *d,
- const struct cpumask *cpu_map, struct sched_domain_attr *attr,
- struct sched_domain *parent, int i)
-{
- struct sched_domain *sd;
- sd = &per_cpu(phys_domains, i).sd;
- SD_INIT(sd, CPU);
- set_domain_attribute(sd, attr);
- cpumask_copy(sched_domain_span(sd), d->nodemask);
- sd->parent = parent;
- if (parent)
- parent->child = sd;
- cpu_to_phys_group(i, cpu_map, &sd->groups, d->tmpmask);
- return sd;
-}
+ WARN_ON_ONCE(*per_cpu_ptr(sdd->sd, cpu) != sd);
+ *per_cpu_ptr(sdd->sd, cpu) = NULL;
-static struct sched_domain *__build_book_sched_domain(struct s_data *d,
- const struct cpumask *cpu_map, struct sched_domain_attr *attr,
- struct sched_domain *parent, int i)
-{
- struct sched_domain *sd = parent;
-#ifdef CONFIG_SCHED_BOOK
- sd = &per_cpu(book_domains, i).sd;
- SD_INIT(sd, BOOK);
- set_domain_attribute(sd, attr);
- cpumask_and(sched_domain_span(sd), cpu_map, cpu_book_mask(i));
- sd->parent = parent;
- parent->child = sd;
- cpu_to_book_group(i, cpu_map, &sd->groups, d->tmpmask);
-#endif
- return sd;
+ if (cpu == cpumask_first(sched_group_cpus(sg))) {
+ WARN_ON_ONCE(*per_cpu_ptr(sdd->sg, cpu) != sg);
+ *per_cpu_ptr(sdd->sg, cpu) = NULL;
+ }
}
-static struct sched_domain *__build_mc_sched_domain(struct s_data *d,
- const struct cpumask *cpu_map, struct sched_domain_attr *attr,
- struct sched_domain *parent, int i)
+#ifdef CONFIG_SCHED_SMT
+static const struct cpumask *cpu_smt_mask(int cpu)
{
- struct sched_domain *sd = parent;
-#ifdef CONFIG_SCHED_MC
- sd = &per_cpu(core_domains, i).sd;
- SD_INIT(sd, MC);
- set_domain_attribute(sd, attr);
- cpumask_and(sched_domain_span(sd), cpu_map, cpu_coregroup_mask(i));
- sd->parent = parent;
- parent->child = sd;
- cpu_to_core_group(i, cpu_map, &sd->groups, d->tmpmask);
-#endif
- return sd;
+ return topology_thread_cpumask(cpu);
}
-
-static struct sched_domain *__build_smt_sched_domain(struct s_data *d,
- const struct cpumask *cpu_map, struct sched_domain_attr *attr,
- struct sched_domain *parent, int i)
-{
- struct sched_domain *sd = parent;
-#ifdef CONFIG_SCHED_SMT
- sd = &per_cpu(cpu_domains, i).sd;
- SD_INIT(sd, SIBLING);
- set_domain_attribute(sd, attr);
- cpumask_and(sched_domain_span(sd), cpu_map, topology_thread_cpumask(i));
- sd->parent = parent;
- parent->child = sd;
- cpu_to_cpu_group(i, cpu_map, &sd->groups, d->tmpmask);
#endif
- return sd;
-}
-static void build_sched_groups(struct s_data *d, enum sched_domain_level l,
- const struct cpumask *cpu_map, int cpu)
-{
- switch (l) {
+/*
+ * Topology list, bottom-up.
+ */
+static struct sched_domain_topology_level default_topology[] = {
#ifdef CONFIG_SCHED_SMT
- case SD_LV_SIBLING: /* set up CPU (sibling) groups */
- cpumask_and(d->this_sibling_map, cpu_map,
- topology_thread_cpumask(cpu));
- if (cpu == cpumask_first(d->this_sibling_map))
- init_sched_build_groups(d->this_sibling_map, cpu_map,
- &cpu_to_cpu_group,
- d->send_covered, d->tmpmask);
- break;
+ { sd_init_SIBLING, cpu_smt_mask, },
#endif
#ifdef CONFIG_SCHED_MC
- case SD_LV_MC: /* set up multi-core groups */
- cpumask_and(d->this_core_map, cpu_map, cpu_coregroup_mask(cpu));
- if (cpu == cpumask_first(d->this_core_map))
- init_sched_build_groups(d->this_core_map, cpu_map,
- &cpu_to_core_group,
- d->send_covered, d->tmpmask);
- break;
+ { sd_init_MC, cpu_coregroup_mask, },
#endif
#ifdef CONFIG_SCHED_BOOK
- case SD_LV_BOOK: /* set up book groups */
- cpumask_and(d->this_book_map, cpu_map, cpu_book_mask(cpu));
- if (cpu == cpumask_first(d->this_book_map))
- init_sched_build_groups(d->this_book_map, cpu_map,
- &cpu_to_book_group,
- d->send_covered, d->tmpmask);
- break;
+ { sd_init_BOOK, cpu_book_mask, },
#endif
- case SD_LV_CPU: /* set up physical groups */
- cpumask_and(d->nodemask, cpumask_of_node(cpu), cpu_map);
- if (!cpumask_empty(d->nodemask))
- init_sched_build_groups(d->nodemask, cpu_map,
- &cpu_to_phys_group,
- d->send_covered, d->tmpmask);
- break;
+ { sd_init_CPU, cpu_cpu_mask, },
#ifdef CONFIG_NUMA
- case SD_LV_ALLNODES:
- init_sched_build_groups(cpu_map, cpu_map, &cpu_to_allnodes_group,
- d->send_covered, d->tmpmask);
- break;
+ { sd_init_NODE, cpu_node_mask, },
+ { sd_init_ALLNODES, cpu_allnodes_mask, },
#endif
- default:
- break;
+ { NULL, },
+};
+
+static struct sched_domain_topology_level *sched_domain_topology = default_topology;
+
+static int __sdt_alloc(const struct cpumask *cpu_map)
+{
+ struct sched_domain_topology_level *tl;
+ int j;
+
+ for (tl = sched_domain_topology; tl->init; tl++) {
+ struct sd_data *sdd = &tl->data;
+
+ sdd->sd = alloc_percpu(struct sched_domain *);
+ if (!sdd->sd)
+ return -ENOMEM;
+
+ sdd->sg = alloc_percpu(struct sched_group *);
+ if (!sdd->sg)
+ return -ENOMEM;
+
+ for_each_cpu(j, cpu_map) {
+ struct sched_domain *sd;
+ struct sched_group *sg;
+
+ sd = kzalloc_node(sizeof(struct sched_domain) + cpumask_size(),
+ GFP_KERNEL, cpu_to_node(j));
+ if (!sd)
+ return -ENOMEM;
+
+ *per_cpu_ptr(sdd->sd, j) = sd;
+
+ sg = kzalloc_node(sizeof(struct sched_group) + cpumask_size(),
+ GFP_KERNEL, cpu_to_node(j));
+ if (!sg)
+ return -ENOMEM;
+
+ *per_cpu_ptr(sdd->sg, j) = sg;
+ }
+ }
+
+ return 0;
+}
+
+static void __sdt_free(const struct cpumask *cpu_map)
+{
+ struct sched_domain_topology_level *tl;
+ int j;
+
+ for (tl = sched_domain_topology; tl->init; tl++) {
+ struct sd_data *sdd = &tl->data;
+
+ for_each_cpu(j, cpu_map) {
+ kfree(*per_cpu_ptr(sdd->sd, j));
+ kfree(*per_cpu_ptr(sdd->sg, j));
+ }
+ free_percpu(sdd->sd);
+ free_percpu(sdd->sg);
+ }
+}
+
+struct sched_domain *build_sched_domain(struct sched_domain_topology_level *tl,
+ struct s_data *d, const struct cpumask *cpu_map,
+ struct sched_domain_attr *attr, struct sched_domain *child,
+ int cpu)
+{
+ struct sched_domain *sd = tl->init(tl, cpu);
+ if (!sd)
+ return child;
+
+ set_domain_attribute(sd, attr);
+ cpumask_and(sched_domain_span(sd), cpu_map, tl->mask(cpu));
+ if (child) {
+ sd->level = child->level + 1;
+ sched_domain_level_max = max(sched_domain_level_max, sd->level);
+ child->parent = sd;
}
+ sd->child = child;
+
+ return sd;
}
/*
* Build sched domains for a given set of cpus and attach the sched domains
* to the individual cpus
*/
-static int __build_sched_domains(const struct cpumask *cpu_map,
- struct sched_domain_attr *attr)
+static int build_sched_domains(const struct cpumask *cpu_map,
+ struct sched_domain_attr *attr)
{
enum s_alloc alloc_state = sa_none;
- struct s_data d;
struct sched_domain *sd;
- int i;
-#ifdef CONFIG_NUMA
- d.sd_allnodes = 0;
-#endif
+ struct s_data d;
+ int i, ret = -ENOMEM;
alloc_state = __visit_domain_allocation_hell(&d, cpu_map);
if (alloc_state != sa_rootdomain)
goto error;
- alloc_state = sa_sched_groups;
- /*
- * Set up domains for cpus specified by the cpu_map.
- */
+ /* Set up domains for cpus specified by the cpu_map. */
for_each_cpu(i, cpu_map) {
- cpumask_and(d.nodemask, cpumask_of_node(cpu_to_node(i)),
- cpu_map);
+ struct sched_domain_topology_level *tl;
- sd = __build_numa_sched_domains(&d, cpu_map, attr, i);
- sd = __build_cpu_sched_domain(&d, cpu_map, attr, sd, i);
- sd = __build_book_sched_domain(&d, cpu_map, attr, sd, i);
- sd = __build_mc_sched_domain(&d, cpu_map, attr, sd, i);
- sd = __build_smt_sched_domain(&d, cpu_map, attr, sd, i);
- }
-
- for_each_cpu(i, cpu_map) {
- build_sched_groups(&d, SD_LV_SIBLING, cpu_map, i);
- build_sched_groups(&d, SD_LV_BOOK, cpu_map, i);
- build_sched_groups(&d, SD_LV_MC, cpu_map, i);
- }
-
- /* Set up physical groups */
- for (i = 0; i < nr_node_ids; i++)
- build_sched_groups(&d, SD_LV_CPU, cpu_map, i);
+ sd = NULL;
+ for (tl = sched_domain_topology; tl->init; tl++)
+ sd = build_sched_domain(tl, &d, cpu_map, attr, sd, i);
-#ifdef CONFIG_NUMA
- /* Set up node groups */
- if (d.sd_allnodes)
- build_sched_groups(&d, SD_LV_ALLNODES, cpu_map, 0);
-
- for (i = 0; i < nr_node_ids; i++)
- if (build_numa_sched_groups(&d, cpu_map, i))
- goto error;
-#endif
+ while (sd->child)
+ sd = sd->child;
- /* Calculate CPU power for physical packages and nodes */
-#ifdef CONFIG_SCHED_SMT
- for_each_cpu(i, cpu_map) {
- sd = &per_cpu(cpu_domains, i).sd;
- init_sched_groups_power(i, sd);
- }
-#endif
-#ifdef CONFIG_SCHED_MC
- for_each_cpu(i, cpu_map) {
- sd = &per_cpu(core_domains, i).sd;
- init_sched_groups_power(i, sd);
+ *per_cpu_ptr(d.sd, i) = sd;
}
-#endif
-#ifdef CONFIG_SCHED_BOOK
- for_each_cpu(i, cpu_map) {
- sd = &per_cpu(book_domains, i).sd;
- init_sched_groups_power(i, sd);
- }
-#endif
+ /* Build the groups for the domains */
for_each_cpu(i, cpu_map) {
- sd = &per_cpu(phys_domains, i).sd;
- init_sched_groups_power(i, sd);
- }
+ for (sd = *per_cpu_ptr(d.sd, i); sd; sd = sd->parent) {
+ sd->span_weight = cpumask_weight(sched_domain_span(sd));
+ get_group(i, sd->private, &sd->groups);
+ atomic_inc(&sd->groups->ref);
-#ifdef CONFIG_NUMA
- for (i = 0; i < nr_node_ids; i++)
- init_numa_sched_groups_power(d.sched_group_nodes[i]);
+ if (i != cpumask_first(sched_domain_span(sd)))
+ continue;
- if (d.sd_allnodes) {
- struct sched_group *sg;
+ build_sched_groups(sd);
+ }
+ }
- cpu_to_allnodes_group(cpumask_first(cpu_map), cpu_map, &sg,
- d.tmpmask);
- init_numa_sched_groups_power(sg);
+ /* Calculate CPU power for physical packages and nodes */
+ for (i = nr_cpumask_bits-1; i >= 0; i--) {
+ if (!cpumask_test_cpu(i, cpu_map))
+ continue;
+
+ for (sd = *per_cpu_ptr(d.sd, i); sd; sd = sd->parent) {
+ claim_allocations(i, sd);
+ init_sched_groups_power(i, sd);
+ }
}
-#endif
/* Attach the domains */
+ rcu_read_lock();
for_each_cpu(i, cpu_map) {
-#ifdef CONFIG_SCHED_SMT
- sd = &per_cpu(cpu_domains, i).sd;
-#elif defined(CONFIG_SCHED_MC)
- sd = &per_cpu(core_domains, i).sd;
-#elif defined(CONFIG_SCHED_BOOK)
- sd = &per_cpu(book_domains, i).sd;
-#else
- sd = &per_cpu(phys_domains, i).sd;
-#endif
+ sd = *per_cpu_ptr(d.sd, i);
cpu_attach_domain(sd, d.rd, i);
}
+ rcu_read_unlock();
- d.sched_group_nodes = NULL; /* don't free this we still need it */
- __free_domain_allocs(&d, sa_tmpmask, cpu_map);
- return 0;
-
+ ret = 0;
error:
__free_domain_allocs(&d, alloc_state, cpu_map);
- return -ENOMEM;
-}
-
-static int build_sched_domains(const struct cpumask *cpu_map)
-{
- return __build_sched_domains(cpu_map, NULL);
+ return ret;
}
static cpumask_var_t *doms_cur; /* current sched domains */
@@ -7670,7 +7362,7 @@ void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms)
* For now this just excludes isolated cpus, but could be used to
* exclude other special cases in the future.
*/
-static int arch_init_sched_domains(const struct cpumask *cpu_map)
+static int init_sched_domains(const struct cpumask *cpu_map)
{
int err;
@@ -7681,32 +7373,24 @@ static int arch_init_sched_domains(const struct cpumask *cpu_map)
doms_cur = &fallback_doms;
cpumask_andnot(doms_cur[0], cpu_map, cpu_isolated_map);
dattr_cur = NULL;
- err = build_sched_domains(doms_cur[0]);
+ err = build_sched_domains(doms_cur[0], NULL);
register_sched_domain_sysctl();
return err;
}
-static void arch_destroy_sched_domains(const struct cpumask *cpu_map,
- struct cpumask *tmpmask)
-{
- free_sched_groups(cpu_map, tmpmask);
-}
-
/*
* Detach sched domains from a group of cpus specified in cpu_map
* These cpus will now be attached to the NULL domain
*/
static void detach_destroy_domains(const struct cpumask *cpu_map)
{
- /* Save because hotplug lock held. */
- static DECLARE_BITMAP(tmpmask, CONFIG_NR_CPUS);
int i;
+ rcu_read_lock();
for_each_cpu(i, cpu_map)
cpu_attach_domain(NULL, &def_root_domain, i);
- synchronize_sched();
- arch_destroy_sched_domains(cpu_map, to_cpumask(tmpmask));
+ rcu_read_unlock();
}
/* handle null as "default" */
@@ -7795,8 +7479,7 @@ match1:
goto match2;
}
/* no match - add a new doms_new */
- __build_sched_domains(doms_new[i],
- dattr_new ? dattr_new + i : NULL);
+ build_sched_domains(doms_new[i], dattr_new ? dattr_new + i : NULL);
match2:
;
}
@@ -7815,7 +7498,7 @@ match2:
}
#if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT)
-static void arch_reinit_sched_domains(void)
+static void reinit_sched_domains(void)
{
get_online_cpus();
@@ -7848,7 +7531,7 @@ static ssize_t sched_power_savings_store(const char *buf, size_t count, int smt)
else
sched_mc_power_savings = level;
- arch_reinit_sched_domains();
+ reinit_sched_domains();
return count;
}
@@ -7967,14 +7650,9 @@ void __init sched_init_smp(void)
alloc_cpumask_var(&non_isolated_cpus, GFP_KERNEL);
alloc_cpumask_var(&fallback_doms, GFP_KERNEL);
-#if defined(CONFIG_NUMA)
- sched_group_nodes_bycpu = kzalloc(nr_cpu_ids * sizeof(void **),
- GFP_KERNEL);
- BUG_ON(sched_group_nodes_bycpu == NULL);
-#endif
get_online_cpus();
mutex_lock(&sched_domains_mutex);
- arch_init_sched_domains(cpu_active_mask);
+ init_sched_domains(cpu_active_mask);
cpumask_andnot(non_isolated_cpus, cpu_possible_mask, cpu_isolated_map);
if (cpumask_empty(non_isolated_cpus))
cpumask_set_cpu(smp_processor_id(), non_isolated_cpus);
@@ -8281,6 +7959,7 @@ void __init sched_init(void)
/* Allocate the nohz_cpu_mask if CONFIG_CPUMASK_OFFSTACK */
zalloc_cpumask_var(&nohz_cpu_mask, GFP_NOWAIT);
#ifdef CONFIG_SMP
+ zalloc_cpumask_var(&sched_domains_tmpmask, GFP_NOWAIT);
#ifdef CONFIG_NO_HZ
zalloc_cpumask_var(&nohz.idle_cpus_mask, GFP_NOWAIT);
alloc_cpumask_var(&nohz.grp_idle_mask, GFP_NOWAIT);
@@ -8340,7 +8019,7 @@ static void normalize_task(struct rq *rq, struct task_struct *p)
int old_prio = p->prio;
int on_rq;
- on_rq = p->se.on_rq;
+ on_rq = p->on_rq;
if (on_rq)
deactivate_task(rq, p, 0);
__setscheduler(rq, p, SCHED_NORMAL, 0);
@@ -8553,7 +8232,6 @@ int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent)
{
struct rt_rq *rt_rq;
struct sched_rt_entity *rt_se;
- struct rq *rq;
int i;
tg->rt_rq = kzalloc(sizeof(rt_rq) * nr_cpu_ids, GFP_KERNEL);
@@ -8567,8 +8245,6 @@ int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent)
ktime_to_ns(def_rt_bandwidth.rt_period), 0);
for_each_possible_cpu(i) {
- rq = cpu_rq(i);
-
rt_rq = kzalloc_node(sizeof(struct rt_rq),
GFP_KERNEL, cpu_to_node(i));
if (!rt_rq)
@@ -8683,7 +8359,7 @@ void sched_move_task(struct task_struct *tsk)
rq = task_rq_lock(tsk, &flags);
running = task_current(rq, tsk);
- on_rq = tsk->se.on_rq;
+ on_rq = tsk->on_rq;
if (on_rq)
dequeue_task(rq, tsk, 0);
@@ -8702,7 +8378,7 @@ void sched_move_task(struct task_struct *tsk)
if (on_rq)
enqueue_task(rq, tsk, 0);
- task_rq_unlock(rq, &flags);
+ task_rq_unlock(rq, tsk, &flags);
}
#endif /* CONFIG_CGROUP_SCHED */
diff --git a/kernel/sched_debug.c b/kernel/sched_debug.c
index 7bacd83a415..a6710a112b4 100644
--- a/kernel/sched_debug.c
+++ b/kernel/sched_debug.c
@@ -152,7 +152,7 @@ static void print_rq(struct seq_file *m, struct rq *rq, int rq_cpu)
read_lock_irqsave(&tasklist_lock, flags);
do_each_thread(g, p) {
- if (!p->se.on_rq || task_cpu(p) != rq_cpu)
+ if (!p->on_rq || task_cpu(p) != rq_cpu)
continue;
print_task(m, rq, p);
@@ -296,9 +296,6 @@ static void print_cpu(struct seq_file *m, int cpu)
P(ttwu_count);
P(ttwu_local);
- SEQ_printf(m, " .%-30s: %d\n", "bkl_count",
- rq->rq_sched_info.bkl_count);
-
#undef P
#undef P64
#endif
@@ -441,7 +438,6 @@ void proc_sched_show_task(struct task_struct *p, struct seq_file *m)
P(se.statistics.wait_count);
PN(se.statistics.iowait_sum);
P(se.statistics.iowait_count);
- P(sched_info.bkl_count);
P(se.nr_migrations);
P(se.statistics.nr_migrations_cold);
P(se.statistics.nr_failed_migrations_affine);
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 6fa833ab2cb..37f22626225 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -358,6 +358,10 @@ static void update_min_vruntime(struct cfs_rq *cfs_rq)
}
cfs_rq->min_vruntime = max_vruntime(cfs_rq->min_vruntime, vruntime);
+#ifndef CONFIG_64BIT
+ smp_wmb();
+ cfs_rq->min_vruntime_copy = cfs_rq->min_vruntime;
+#endif
}
/*
@@ -1340,6 +1344,8 @@ enqueue_task_fair(struct rq *rq, struct task_struct *p, int flags)
hrtick_update(rq);
}
+static void set_next_buddy(struct sched_entity *se);
+
/*
* The dequeue_task method is called before nr_running is
* decreased. We remove the task from the rbtree and
@@ -1349,14 +1355,22 @@ static void dequeue_task_fair(struct rq *rq, struct task_struct *p, int flags)
{
struct cfs_rq *cfs_rq;
struct sched_entity *se = &p->se;
+ int task_sleep = flags & DEQUEUE_SLEEP;
for_each_sched_entity(se) {
cfs_rq = cfs_rq_of(se);
dequeue_entity(cfs_rq, se, flags);
/* Don't dequeue parent if it has other entities besides us */
- if (cfs_rq->load.weight)
+ if (cfs_rq->load.weight) {
+ /*
+ * Bias pick_next to pick a task from this cfs_rq, as
+ * p is sleeping when it is within its sched_slice.
+ */
+ if (task_sleep && parent_entity(se))
+ set_next_buddy(parent_entity(se));
break;
+ }
flags |= DEQUEUE_SLEEP;
}
@@ -1372,12 +1386,25 @@ static void dequeue_task_fair(struct rq *rq, struct task_struct *p, int flags)
#ifdef CONFIG_SMP
-static void task_waking_fair(struct rq *rq, struct task_struct *p)
+static void task_waking_fair(struct task_struct *p)
{
struct sched_entity *se = &p->se;
struct cfs_rq *cfs_rq = cfs_rq_of(se);
+ u64 min_vruntime;
- se->vruntime -= cfs_rq->min_vruntime;
+#ifndef CONFIG_64BIT
+ u64 min_vruntime_copy;
+
+ do {
+ min_vruntime_copy = cfs_rq->min_vruntime_copy;
+ smp_rmb();
+ min_vruntime = cfs_rq->min_vruntime;
+ } while (min_vruntime != min_vruntime_copy);
+#else
+ min_vruntime = cfs_rq->min_vruntime;
+#endif
+
+ se->vruntime -= min_vruntime;
}
#ifdef CONFIG_FAIR_GROUP_SCHED
@@ -1622,6 +1649,7 @@ static int select_idle_sibling(struct task_struct *p, int target)
/*
* Otherwise, iterate the domains and find an elegible idle cpu.
*/
+ rcu_read_lock();
for_each_domain(target, sd) {
if (!(sd->flags & SD_SHARE_PKG_RESOURCES))
break;
@@ -1641,6 +1669,7 @@ static int select_idle_sibling(struct task_struct *p, int target)
cpumask_test_cpu(prev_cpu, sched_domain_span(sd)))
break;
}
+ rcu_read_unlock();
return target;
}
@@ -1657,7 +1686,7 @@ static int select_idle_sibling(struct task_struct *p, int target)
* preempt must be disabled.
*/
static int
-select_task_rq_fair(struct rq *rq, struct task_struct *p, int sd_flag, int wake_flags)
+select_task_rq_fair(struct task_struct *p, int sd_flag, int wake_flags)
{
struct sched_domain *tmp, *affine_sd = NULL, *sd = NULL;
int cpu = smp_processor_id();
@@ -1673,6 +1702,7 @@ select_task_rq_fair(struct rq *rq, struct task_struct *p, int sd_flag, int wake_
new_cpu = prev_cpu;
}
+ rcu_read_lock();
for_each_domain(cpu, tmp) {
if (!(tmp->flags & SD_LOAD_BALANCE))
continue;
@@ -1723,9 +1753,10 @@ select_task_rq_fair(struct rq *rq, struct task_struct *p, int sd_flag, int wake_
if (affine_sd) {
if (cpu == prev_cpu || wake_affine(affine_sd, p, sync))
- return select_idle_sibling(p, cpu);
- else
- return select_idle_sibling(p, prev_cpu);
+ prev_cpu = cpu;
+
+ new_cpu = select_idle_sibling(p, prev_cpu);
+ goto unlock;
}
while (sd) {
@@ -1766,6 +1797,8 @@ select_task_rq_fair(struct rq *rq, struct task_struct *p, int sd_flag, int wake_
}
/* while loop will break here if sd == NULL */
}
+unlock:
+ rcu_read_unlock();
return new_cpu;
}
@@ -1789,10 +1822,7 @@ wakeup_gran(struct sched_entity *curr, struct sched_entity *se)
* This is especially important for buddies when the leftmost
* task is higher priority than the buddy.
*/
- if (unlikely(se->load.weight != NICE_0_LOAD))
- gran = calc_delta_fair(gran, se);
-
- return gran;
+ return calc_delta_fair(gran, se);
}
/*
@@ -1826,26 +1856,26 @@ wakeup_preempt_entity(struct sched_entity *curr, struct sched_entity *se)
static void set_last_buddy(struct sched_entity *se)
{
- if (likely(task_of(se)->policy != SCHED_IDLE)) {
- for_each_sched_entity(se)
- cfs_rq_of(se)->last = se;
- }
+ if (entity_is_task(se) && unlikely(task_of(se)->policy == SCHED_IDLE))
+ return;
+
+ for_each_sched_entity(se)
+ cfs_rq_of(se)->last = se;
}
static void set_next_buddy(struct sched_entity *se)
{
- if (likely(task_of(se)->policy != SCHED_IDLE)) {
- for_each_sched_entity(se)
- cfs_rq_of(se)->next = se;
- }
+ if (entity_is_task(se) && unlikely(task_of(se)->policy == SCHED_IDLE))
+ return;
+
+ for_each_sched_entity(se)
+ cfs_rq_of(se)->next = se;
}
static void set_skip_buddy(struct sched_entity *se)
{
- if (likely(task_of(se)->policy != SCHED_IDLE)) {
- for_each_sched_entity(se)
- cfs_rq_of(se)->skip = se;
- }
+ for_each_sched_entity(se)
+ cfs_rq_of(se)->skip = se;
}
/*
@@ -1857,12 +1887,15 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int wake_
struct sched_entity *se = &curr->se, *pse = &p->se;
struct cfs_rq *cfs_rq = task_cfs_rq(curr);
int scale = cfs_rq->nr_running >= sched_nr_latency;
+ int next_buddy_marked = 0;
if (unlikely(se == pse))
return;
- if (sched_feat(NEXT_BUDDY) && scale && !(wake_flags & WF_FORK))
+ if (sched_feat(NEXT_BUDDY) && scale && !(wake_flags & WF_FORK)) {
set_next_buddy(pse);
+ next_buddy_marked = 1;
+ }
/*
* We can come here with TIF_NEED_RESCHED already set from new task
@@ -1890,8 +1923,15 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int wake_
update_curr(cfs_rq);
find_matching_se(&se, &pse);
BUG_ON(!pse);
- if (wakeup_preempt_entity(se, pse) == 1)
+ if (wakeup_preempt_entity(se, pse) == 1) {
+ /*
+ * Bias pick_next to pick the sched entity that is
+ * triggering this preemption.
+ */
+ if (!next_buddy_marked)
+ set_next_buddy(pse);
goto preempt;
+ }
return;
@@ -2102,7 +2142,7 @@ static unsigned long
balance_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest,
unsigned long max_load_move, struct sched_domain *sd,
enum cpu_idle_type idle, int *all_pinned,
- int *this_best_prio, struct cfs_rq *busiest_cfs_rq)
+ struct cfs_rq *busiest_cfs_rq)
{
int loops = 0, pulled = 0;
long rem_load_move = max_load_move;
@@ -2140,9 +2180,6 @@ balance_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest,
*/
if (rem_load_move <= 0)
break;
-
- if (p->prio < *this_best_prio)
- *this_best_prio = p->prio;
}
out:
/*
@@ -2202,7 +2239,7 @@ static unsigned long
load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
unsigned long max_load_move,
struct sched_domain *sd, enum cpu_idle_type idle,
- int *all_pinned, int *this_best_prio)
+ int *all_pinned)
{
long rem_load_move = max_load_move;
int busiest_cpu = cpu_of(busiest);
@@ -2227,7 +2264,7 @@ load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
rem_load = div_u64(rem_load, busiest_h_load + 1);
moved_load = balance_tasks(this_rq, this_cpu, busiest,
- rem_load, sd, idle, all_pinned, this_best_prio,
+ rem_load, sd, idle, all_pinned,
busiest_cfs_rq);
if (!moved_load)
@@ -2253,11 +2290,11 @@ static unsigned long
load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
unsigned long max_load_move,
struct sched_domain *sd, enum cpu_idle_type idle,
- int *all_pinned, int *this_best_prio)
+ int *all_pinned)
{
return balance_tasks(this_rq, this_cpu, busiest,
max_load_move, sd, idle, all_pinned,
- this_best_prio, &busiest->cfs);
+ &busiest->cfs);
}
#endif
@@ -2274,12 +2311,11 @@ static int move_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest,
int *all_pinned)
{
unsigned long total_load_moved = 0, load_moved;
- int this_best_prio = this_rq->curr->prio;
do {
load_moved = load_balance_fair(this_rq, this_cpu, busiest,
max_load_move - total_load_moved,
- sd, idle, all_pinned, &this_best_prio);
+ sd, idle, all_pinned);
total_load_moved += load_moved;
@@ -2648,7 +2684,7 @@ fix_small_capacity(struct sched_domain *sd, struct sched_group *group)
/*
* Only siblings can have significantly less than SCHED_LOAD_SCALE
*/
- if (sd->level != SD_LV_SIBLING)
+ if (!(sd->flags & SD_SHARE_CPUPOWER))
return 0;
/*
@@ -3465,6 +3501,7 @@ static void idle_balance(int this_cpu, struct rq *this_rq)
raw_spin_unlock(&this_rq->lock);
update_shares(this_cpu);
+ rcu_read_lock();
for_each_domain(this_cpu, sd) {
unsigned long interval;
int balance = 1;
@@ -3486,6 +3523,7 @@ static void idle_balance(int this_cpu, struct rq *this_rq)
break;
}
}
+ rcu_read_unlock();
raw_spin_lock(&this_rq->lock);
@@ -3534,6 +3572,7 @@ static int active_load_balance_cpu_stop(void *data)
double_lock_balance(busiest_rq, target_rq);
/* Search for an sd spanning us and the target CPU. */
+ rcu_read_lock();
for_each_domain(target_cpu, sd) {
if ((sd->flags & SD_LOAD_BALANCE) &&
cpumask_test_cpu(busiest_cpu, sched_domain_span(sd)))
@@ -3549,6 +3588,7 @@ static int active_load_balance_cpu_stop(void *data)
else
schedstat_inc(sd, alb_failed);
}
+ rcu_read_unlock();
double_unlock_balance(busiest_rq, target_rq);
out_unlock:
busiest_rq->active_balance = 0;
@@ -3675,6 +3715,7 @@ static int find_new_ilb(int cpu)
{
struct sched_domain *sd;
struct sched_group *ilb_group;
+ int ilb = nr_cpu_ids;
/*
* Have idle load balancer selection from semi-idle packages only
@@ -3690,20 +3731,25 @@ static int find_new_ilb(int cpu)
if (cpumask_weight(nohz.idle_cpus_mask) < 2)
goto out_done;
+ rcu_read_lock();
for_each_flag_domain(cpu, sd, SD_POWERSAVINGS_BALANCE) {
ilb_group = sd->groups;
do {
- if (is_semi_idle_group(ilb_group))
- return cpumask_first(nohz.grp_idle_mask);
+ if (is_semi_idle_group(ilb_group)) {
+ ilb = cpumask_first(nohz.grp_idle_mask);
+ goto unlock;
+ }
ilb_group = ilb_group->next;
} while (ilb_group != sd->groups);
}
+unlock:
+ rcu_read_unlock();
out_done:
- return nr_cpu_ids;
+ return ilb;
}
#else /* (CONFIG_SCHED_MC || CONFIG_SCHED_SMT) */
static inline int find_new_ilb(int call_cpu)
@@ -3848,6 +3894,7 @@ static void rebalance_domains(int cpu, enum cpu_idle_type idle)
update_shares(cpu);
+ rcu_read_lock();
for_each_domain(cpu, sd) {
if (!(sd->flags & SD_LOAD_BALANCE))
continue;
@@ -3893,6 +3940,7 @@ out:
if (!balance)
break;
}
+ rcu_read_unlock();
/*
* next_balance will be updated only when there is a need.
diff --git a/kernel/sched_features.h b/kernel/sched_features.h
index 68e69acc29b..be40f7371ee 100644
--- a/kernel/sched_features.h
+++ b/kernel/sched_features.h
@@ -64,3 +64,9 @@ SCHED_FEAT(OWNER_SPIN, 1)
* Decrement CPU power based on irq activity
*/
SCHED_FEAT(NONIRQ_POWER, 1)
+
+/*
+ * Queue remote wakeups on the target CPU and process them
+ * using the scheduler IPI. Reduces rq->lock contention/bounces.
+ */
+SCHED_FEAT(TTWU_QUEUE, 1)
diff --git a/kernel/sched_idletask.c b/kernel/sched_idletask.c
index a776a639642..0a51882534e 100644
--- a/kernel/sched_idletask.c
+++ b/kernel/sched_idletask.c
@@ -7,7 +7,7 @@
#ifdef CONFIG_SMP
static int
-select_task_rq_idle(struct rq *rq, struct task_struct *p, int sd_flag, int flags)
+select_task_rq_idle(struct task_struct *p, int sd_flag, int flags)
{
return task_cpu(p); /* IDLE tasks as never migrated */
}
diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c
index e7cebdc65f8..64b2a37c07d 100644
--- a/kernel/sched_rt.c
+++ b/kernel/sched_rt.c
@@ -183,6 +183,14 @@ static inline u64 sched_rt_period(struct rt_rq *rt_rq)
return ktime_to_ns(rt_rq->tg->rt_bandwidth.rt_period);
}
+typedef struct task_group *rt_rq_iter_t;
+
+#define for_each_rt_rq(rt_rq, iter, rq) \
+ for (iter = list_entry_rcu(task_groups.next, typeof(*iter), list); \
+ (&iter->list != &task_groups) && \
+ (rt_rq = iter->rt_rq[cpu_of(rq)]); \
+ iter = list_entry_rcu(iter->list.next, typeof(*iter), list))
+
static inline void list_add_leaf_rt_rq(struct rt_rq *rt_rq)
{
list_add_rcu(&rt_rq->leaf_rt_rq_list,
@@ -288,6 +296,11 @@ static inline u64 sched_rt_period(struct rt_rq *rt_rq)
return ktime_to_ns(def_rt_bandwidth.rt_period);
}
+typedef struct rt_rq *rt_rq_iter_t;
+
+#define for_each_rt_rq(rt_rq, iter, rq) \
+ for ((void) iter, rt_rq = &rq->rt; rt_rq; rt_rq = NULL)
+
static inline void list_add_leaf_rt_rq(struct rt_rq *rt_rq)
{
}
@@ -402,12 +415,13 @@ next:
static void __disable_runtime(struct rq *rq)
{
struct root_domain *rd = rq->rd;
+ rt_rq_iter_t iter;
struct rt_rq *rt_rq;
if (unlikely(!scheduler_running))
return;
- for_each_leaf_rt_rq(rt_rq, rq) {
+ for_each_rt_rq(rt_rq, iter, rq) {
struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq);
s64 want;
int i;
@@ -487,6 +501,7 @@ static void disable_runtime(struct rq *rq)
static void __enable_runtime(struct rq *rq)
{
+ rt_rq_iter_t iter;
struct rt_rq *rt_rq;
if (unlikely(!scheduler_running))
@@ -495,7 +510,7 @@ static void __enable_runtime(struct rq *rq)
/*
* Reset each runqueue's bandwidth settings
*/
- for_each_leaf_rt_rq(rt_rq, rq) {
+ for_each_rt_rq(rt_rq, iter, rq) {
struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq);
raw_spin_lock(&rt_b->rt_runtime_lock);
@@ -562,6 +577,13 @@ static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun)
if (rt_rq->rt_throttled && rt_rq->rt_time < runtime) {
rt_rq->rt_throttled = 0;
enqueue = 1;
+
+ /*
+ * Force a clock update if the CPU was idle,
+ * lest wakeup -> unthrottle time accumulate.
+ */
+ if (rt_rq->rt_nr_running && rq->curr == rq->idle)
+ rq->skip_clock_update = -1;
}
if (rt_rq->rt_time || rt_rq->rt_nr_running)
idle = 0;
@@ -977,13 +999,23 @@ static void yield_task_rt(struct rq *rq)
static int find_lowest_rq(struct task_struct *task);
static int
-select_task_rq_rt(struct rq *rq, struct task_struct *p, int sd_flag, int flags)
+select_task_rq_rt(struct task_struct *p, int sd_flag, int flags)
{
+ struct task_struct *curr;
+ struct rq *rq;
+ int cpu;
+
if (sd_flag != SD_BALANCE_WAKE)
return smp_processor_id();
+ cpu = task_cpu(p);
+ rq = cpu_rq(cpu);
+
+ rcu_read_lock();
+ curr = ACCESS_ONCE(rq->curr); /* unlocked access */
+
/*
- * If the current task is an RT task, then
+ * If the current task on @p's runqueue is an RT task, then
* try to see if we can wake this RT task up on another
* runqueue. Otherwise simply start this RT task
* on its current runqueue.
@@ -997,21 +1029,25 @@ select_task_rq_rt(struct rq *rq, struct task_struct *p, int sd_flag, int flags)
* lock?
*
* For equal prio tasks, we just let the scheduler sort it out.
+ *
+ * Otherwise, just let it ride on the affined RQ and the
+ * post-schedule router will push the preempted task away
+ *
+ * This test is optimistic, if we get it wrong the load-balancer
+ * will have to sort it out.
*/
- if (unlikely(rt_task(rq->curr)) &&
- (rq->curr->rt.nr_cpus_allowed < 2 ||
- rq->curr->prio < p->prio) &&
+ if (curr && unlikely(rt_task(curr)) &&
+ (curr->rt.nr_cpus_allowed < 2 ||
+ curr->prio < p->prio) &&
(p->rt.nr_cpus_allowed > 1)) {
- int cpu = find_lowest_rq(p);
+ int target = find_lowest_rq(p);
- return (cpu == -1) ? task_cpu(p) : cpu;
+ if (target != -1)
+ cpu = target;
}
+ rcu_read_unlock();
- /*
- * Otherwise, just let it ride on the affined RQ and the
- * post-schedule router will push the preempted task away
- */
- return task_cpu(p);
+ return cpu;
}
static void check_preempt_equal_prio(struct rq *rq, struct task_struct *p)
@@ -1136,7 +1172,7 @@ static void put_prev_task_rt(struct rq *rq, struct task_struct *p)
* The previous task needs to be made eligible for pushing
* if it is still active
*/
- if (p->se.on_rq && p->rt.nr_cpus_allowed > 1)
+ if (on_rt_rq(&p->rt) && p->rt.nr_cpus_allowed > 1)
enqueue_pushable_task(rq, p);
}
@@ -1287,7 +1323,7 @@ static struct rq *find_lock_lowest_rq(struct task_struct *task, struct rq *rq)
!cpumask_test_cpu(lowest_rq->cpu,
&task->cpus_allowed) ||
task_running(rq, task) ||
- !task->se.on_rq)) {
+ !task->on_rq)) {
raw_spin_unlock(&lowest_rq->lock);
lowest_rq = NULL;
@@ -1321,7 +1357,7 @@ static struct task_struct *pick_next_pushable_task(struct rq *rq)
BUG_ON(task_current(rq, p));
BUG_ON(p->rt.nr_cpus_allowed <= 1);
- BUG_ON(!p->se.on_rq);
+ BUG_ON(!p->on_rq);
BUG_ON(!rt_task(p));
return p;
@@ -1467,7 +1503,7 @@ static int pull_rt_task(struct rq *this_rq)
*/
if (p && (p->prio < this_rq->rt.highest_prio.curr)) {
WARN_ON(p == src_rq->curr);
- WARN_ON(!p->se.on_rq);
+ WARN_ON(!p->on_rq);
/*
* There's a chance that p is higher in priority
@@ -1538,7 +1574,7 @@ static void set_cpus_allowed_rt(struct task_struct *p,
* Update the migration status of the RQ if we have an RT task
* which is running AND changing its weight value.
*/
- if (p->se.on_rq && (weight != p->rt.nr_cpus_allowed)) {
+ if (p->on_rq && (weight != p->rt.nr_cpus_allowed)) {
struct rq *rq = task_rq(p);
if (!task_current(rq, p)) {
@@ -1608,7 +1644,7 @@ static void switched_from_rt(struct rq *rq, struct task_struct *p)
* we may need to handle the pulling of RT tasks
* now.
*/
- if (p->se.on_rq && !rq->rt.rt_nr_running)
+ if (p->on_rq && !rq->rt.rt_nr_running)
pull_rt_task(rq);
}
@@ -1638,7 +1674,7 @@ static void switched_to_rt(struct rq *rq, struct task_struct *p)
* If that current running task is also an RT task
* then see if we can move to another run queue.
*/
- if (p->se.on_rq && rq->curr != p) {
+ if (p->on_rq && rq->curr != p) {
#ifdef CONFIG_SMP
if (rq->rt.overloaded && push_rt_task(rq) &&
/* Don't resched if we changed runqueues */
@@ -1657,7 +1693,7 @@ static void switched_to_rt(struct rq *rq, struct task_struct *p)
static void
prio_changed_rt(struct rq *rq, struct task_struct *p, int oldprio)
{
- if (!p->se.on_rq)
+ if (!p->on_rq)
return;
if (rq->curr == p) {
@@ -1796,10 +1832,11 @@ extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq);
static void print_rt_stats(struct seq_file *m, int cpu)
{
+ rt_rq_iter_t iter;
struct rt_rq *rt_rq;
rcu_read_lock();
- for_each_leaf_rt_rq(rt_rq, cpu_rq(cpu))
+ for_each_rt_rq(rt_rq, iter, cpu_rq(cpu))
print_rt_rq(m, cpu, rt_rq);
rcu_read_unlock();
}
diff --git a/kernel/sched_stoptask.c b/kernel/sched_stoptask.c
index 1ba2bd40fda..6f437632afa 100644
--- a/kernel/sched_stoptask.c
+++ b/kernel/sched_stoptask.c
@@ -9,8 +9,7 @@
#ifdef CONFIG_SMP
static int
-select_task_rq_stop(struct rq *rq, struct task_struct *p,
- int sd_flag, int flags)
+select_task_rq_stop(struct task_struct *p, int sd_flag, int flags)
{
return task_cpu(p); /* stop tasks as never migrate */
}
@@ -26,7 +25,7 @@ static struct task_struct *pick_next_task_stop(struct rq *rq)
{
struct task_struct *stop = rq->stop;
- if (stop && stop->se.on_rq)
+ if (stop && stop->on_rq)
return stop;
return NULL;
diff --git a/kernel/softirq.c b/kernel/softirq.c
index 174f976c287..13960170cad 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -58,7 +58,7 @@ DEFINE_PER_CPU(struct task_struct *, ksoftirqd);
char *softirq_to_name[NR_SOFTIRQS] = {
"HI", "TIMER", "NET_TX", "NET_RX", "BLOCK", "BLOCK_IOPOLL",
- "TASKLET", "SCHED", "HRTIMER", "RCU"
+ "TASKLET", "SCHED", "HRTIMER"
};
/*
diff --git a/kernel/sys.c b/kernel/sys.c
index af468edf096..e4128b278f2 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -314,8 +314,8 @@ void kernel_restart_prepare(char *cmd)
{
blocking_notifier_call_chain(&reboot_notifier_list, SYS_RESTART, cmd);
system_state = SYSTEM_RESTART;
+ usermodehelper_disable();
device_shutdown();
- sysdev_shutdown();
syscore_shutdown();
}
@@ -344,6 +344,7 @@ static void kernel_shutdown_prepare(enum system_states state)
blocking_notifier_call_chain(&reboot_notifier_list,
(state == SYSTEM_HALT)?SYS_HALT:SYS_POWER_OFF, NULL);
system_state = state;
+ usermodehelper_disable();
device_shutdown();
}
/**
@@ -354,7 +355,6 @@ static void kernel_shutdown_prepare(enum system_states state)
void kernel_halt(void)
{
kernel_shutdown_prepare(SYSTEM_HALT);
- sysdev_shutdown();
syscore_shutdown();
printk(KERN_EMERG "System halted.\n");
kmsg_dump(KMSG_DUMP_HALT);
@@ -374,7 +374,6 @@ void kernel_power_off(void)
if (pm_power_off_prepare)
pm_power_off_prepare();
disable_nonboot_cpus();
- sysdev_shutdown();
syscore_shutdown();
printk(KERN_EMERG "Power down.\n");
kmsg_dump(KMSG_DUMP_POWEROFF);
diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c
index 0d74b9ba90c..c027d4f602f 100644
--- a/kernel/time/clockevents.c
+++ b/kernel/time/clockevents.c
@@ -194,6 +194,70 @@ void clockevents_register_device(struct clock_event_device *dev)
}
EXPORT_SYMBOL_GPL(clockevents_register_device);
+static void clockevents_config(struct clock_event_device *dev,
+ u32 freq)
+{
+ u64 sec;
+
+ if (!(dev->features & CLOCK_EVT_FEAT_ONESHOT))
+ return;
+
+ /*
+ * Calculate the maximum number of seconds we can sleep. Limit
+ * to 10 minutes for hardware which can program more than
+ * 32bit ticks so we still get reasonable conversion values.
+ */
+ sec = dev->max_delta_ticks;
+ do_div(sec, freq);
+ if (!sec)
+ sec = 1;
+ else if (sec > 600 && dev->max_delta_ticks > UINT_MAX)
+ sec = 600;
+
+ clockevents_calc_mult_shift(dev, freq, sec);
+ dev->min_delta_ns = clockevent_delta2ns(dev->min_delta_ticks, dev);
+ dev->max_delta_ns = clockevent_delta2ns(dev->max_delta_ticks, dev);
+}
+
+/**
+ * clockevents_config_and_register - Configure and register a clock event device
+ * @dev: device to register
+ * @freq: The clock frequency
+ * @min_delta: The minimum clock ticks to program in oneshot mode
+ * @max_delta: The maximum clock ticks to program in oneshot mode
+ *
+ * min/max_delta can be 0 for devices which do not support oneshot mode.
+ */
+void clockevents_config_and_register(struct clock_event_device *dev,
+ u32 freq, unsigned long min_delta,
+ unsigned long max_delta)
+{
+ dev->min_delta_ticks = min_delta;
+ dev->max_delta_ticks = max_delta;
+ clockevents_config(dev, freq);
+ clockevents_register_device(dev);
+}
+
+/**
+ * clockevents_update_freq - Update frequency and reprogram a clock event device.
+ * @dev: device to modify
+ * @freq: new device frequency
+ *
+ * Reconfigure and reprogram a clock event device in oneshot
+ * mode. Must be called on the cpu for which the device delivers per
+ * cpu timer events with interrupts disabled! Returns 0 on success,
+ * -ETIME when the event is in the past.
+ */
+int clockevents_update_freq(struct clock_event_device *dev, u32 freq)
+{
+ clockevents_config(dev, freq);
+
+ if (dev->mode != CLOCK_EVT_MODE_ONESHOT)
+ return 0;
+
+ return clockevents_program_event(dev, dev->next_event, ktime_get());
+}
+
/*
* Noop handler when we shut down an event device
*/
diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
index 6519cf62d9c..1c95fd67732 100644
--- a/kernel/time/clocksource.c
+++ b/kernel/time/clocksource.c
@@ -626,19 +626,6 @@ static void clocksource_enqueue(struct clocksource *cs)
list_add(&cs->list, entry);
}
-
-/*
- * Maximum time we expect to go between ticks. This includes idle
- * tickless time. It provides the trade off between selecting a
- * mult/shift pair that is very precise but can only handle a short
- * period of time, vs. a mult/shift pair that can handle long periods
- * of time but isn't as precise.
- *
- * This is a subsystem constant, and actual hardware limitations
- * may override it (ie: clocksources that wrap every 3 seconds).
- */
-#define MAX_UPDATE_LENGTH 5 /* Seconds */
-
/**
* __clocksource_updatefreq_scale - Used update clocksource with new freq
* @t: clocksource to be registered
@@ -652,15 +639,28 @@ static void clocksource_enqueue(struct clocksource *cs)
*/
void __clocksource_updatefreq_scale(struct clocksource *cs, u32 scale, u32 freq)
{
+ u64 sec;
+
/*
- * Ideally we want to use some of the limits used in
- * clocksource_max_deferment, to provide a more informed
- * MAX_UPDATE_LENGTH. But for now this just gets the
- * register interface working properly.
+ * Calc the maximum number of seconds which we can run before
+ * wrapping around. For clocksources which have a mask > 32bit
+ * we need to limit the max sleep time to have a good
+ * conversion precision. 10 minutes is still a reasonable
+ * amount. That results in a shift value of 24 for a
+ * clocksource with mask >= 40bit and f >= 4GHz. That maps to
+ * ~ 0.06ppm granularity for NTP. We apply the same 12.5%
+ * margin as we do in clocksource_max_deferment()
*/
+ sec = (cs->mask - (cs->mask >> 5));
+ do_div(sec, freq);
+ do_div(sec, scale);
+ if (!sec)
+ sec = 1;
+ else if (sec > 600 && cs->mask > UINT_MAX)
+ sec = 600;
+
clocks_calc_mult_shift(&cs->mult, &cs->shift, freq,
- NSEC_PER_SEC/scale,
- MAX_UPDATE_LENGTH*scale);
+ NSEC_PER_SEC / scale, sec * scale);
cs->max_idle_ns = clocksource_max_deferment(cs);
}
EXPORT_SYMBOL_GPL(__clocksource_updatefreq_scale);
@@ -685,8 +685,8 @@ int __clocksource_register_scale(struct clocksource *cs, u32 scale, u32 freq)
/* Add clocksource to the clcoksource list */
mutex_lock(&clocksource_mutex);
clocksource_enqueue(cs);
- clocksource_select();
clocksource_enqueue_watchdog(cs);
+ clocksource_select();
mutex_unlock(&clocksource_mutex);
return 0;
}
@@ -706,8 +706,8 @@ int clocksource_register(struct clocksource *cs)
mutex_lock(&clocksource_mutex);
clocksource_enqueue(cs);
- clocksource_select();
clocksource_enqueue_watchdog(cs);
+ clocksource_select();
mutex_unlock(&clocksource_mutex);
return 0;
}
diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c
index 827e0f862da..c7218d13273 100644
--- a/kernel/time/tick-broadcast.c
+++ b/kernel/time/tick-broadcast.c
@@ -524,10 +524,11 @@ static void tick_broadcast_init_next_event(struct cpumask *mask,
*/
void tick_broadcast_setup_oneshot(struct clock_event_device *bc)
{
+ int cpu = smp_processor_id();
+
/* Set it up only once ! */
if (bc->event_handler != tick_handle_oneshot_broadcast) {
int was_periodic = bc->mode == CLOCK_EVT_MODE_PERIODIC;
- int cpu = smp_processor_id();
bc->event_handler = tick_handle_oneshot_broadcast;
clockevents_set_mode(bc, CLOCK_EVT_MODE_ONESHOT);
@@ -553,6 +554,15 @@ void tick_broadcast_setup_oneshot(struct clock_event_device *bc)
tick_broadcast_set_event(tick_next_period, 1);
} else
bc->next_event.tv64 = KTIME_MAX;
+ } else {
+ /*
+ * The first cpu which switches to oneshot mode sets
+ * the bit for all other cpus which are in the general
+ * (periodic) broadcast mask. So the bit is set and
+ * would prevent the first broadcast enter after this
+ * to program the bc device.
+ */
+ tick_broadcast_clear_oneshot(cpu);
}
}
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index ee24fa1935a..d017c2c82c4 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -39,20 +39,26 @@
#include "trace_stat.h"
#define FTRACE_WARN_ON(cond) \
- do { \
- if (WARN_ON(cond)) \
+ ({ \
+ int ___r = cond; \
+ if (WARN_ON(___r)) \
ftrace_kill(); \
- } while (0)
+ ___r; \
+ })
#define FTRACE_WARN_ON_ONCE(cond) \
- do { \
- if (WARN_ON_ONCE(cond)) \
+ ({ \
+ int ___r = cond; \
+ if (WARN_ON_ONCE(___r)) \
ftrace_kill(); \
- } while (0)
+ ___r; \
+ })
/* hash bits for specific function selection */
#define FTRACE_HASH_BITS 7
#define FTRACE_FUNC_HASHSIZE (1 << FTRACE_HASH_BITS)
+#define FTRACE_HASH_DEFAULT_BITS 10
+#define FTRACE_HASH_MAX_BITS 12
/* ftrace_enabled is a method to turn ftrace on or off */
int ftrace_enabled __read_mostly;
@@ -81,23 +87,29 @@ static struct ftrace_ops ftrace_list_end __read_mostly =
.func = ftrace_stub,
};
-static struct ftrace_ops *ftrace_list __read_mostly = &ftrace_list_end;
+static struct ftrace_ops *ftrace_global_list __read_mostly = &ftrace_list_end;
+static struct ftrace_ops *ftrace_ops_list __read_mostly = &ftrace_list_end;
ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub;
ftrace_func_t __ftrace_trace_function __read_mostly = ftrace_stub;
ftrace_func_t ftrace_pid_function __read_mostly = ftrace_stub;
+static struct ftrace_ops global_ops;
+
+static void
+ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip);
/*
- * Traverse the ftrace_list, invoking all entries. The reason that we
+ * Traverse the ftrace_global_list, invoking all entries. The reason that we
* can use rcu_dereference_raw() is that elements removed from this list
* are simply leaked, so there is no need to interact with a grace-period
* mechanism. The rcu_dereference_raw() calls are needed to handle
- * concurrent insertions into the ftrace_list.
+ * concurrent insertions into the ftrace_global_list.
*
* Silly Alpha and silly pointer-speculation compiler optimizations!
*/
-static void ftrace_list_func(unsigned long ip, unsigned long parent_ip)
+static void ftrace_global_list_func(unsigned long ip,
+ unsigned long parent_ip)
{
- struct ftrace_ops *op = rcu_dereference_raw(ftrace_list); /*see above*/
+ struct ftrace_ops *op = rcu_dereference_raw(ftrace_global_list); /*see above*/
while (op != &ftrace_list_end) {
op->func(ip, parent_ip);
@@ -147,46 +159,69 @@ static void ftrace_test_stop_func(unsigned long ip, unsigned long parent_ip)
}
#endif
-static int __register_ftrace_function(struct ftrace_ops *ops)
+static void update_global_ops(void)
{
- ops->next = ftrace_list;
+ ftrace_func_t func;
+
/*
- * We are entering ops into the ftrace_list but another
- * CPU might be walking that list. We need to make sure
- * the ops->next pointer is valid before another CPU sees
- * the ops pointer included into the ftrace_list.
+ * If there's only one function registered, then call that
+ * function directly. Otherwise, we need to iterate over the
+ * registered callers.
*/
- rcu_assign_pointer(ftrace_list, ops);
+ if (ftrace_global_list == &ftrace_list_end ||
+ ftrace_global_list->next == &ftrace_list_end)
+ func = ftrace_global_list->func;
+ else
+ func = ftrace_global_list_func;
- if (ftrace_enabled) {
- ftrace_func_t func;
+ /* If we filter on pids, update to use the pid function */
+ if (!list_empty(&ftrace_pids)) {
+ set_ftrace_pid_function(func);
+ func = ftrace_pid_func;
+ }
- if (ops->next == &ftrace_list_end)
- func = ops->func;
- else
- func = ftrace_list_func;
+ global_ops.func = func;
+}
- if (!list_empty(&ftrace_pids)) {
- set_ftrace_pid_function(func);
- func = ftrace_pid_func;
- }
+static void update_ftrace_function(void)
+{
+ ftrace_func_t func;
+
+ update_global_ops();
+
+ /*
+ * If we are at the end of the list and this ops is
+ * not dynamic, then have the mcount trampoline call
+ * the function directly
+ */
+ if (ftrace_ops_list == &ftrace_list_end ||
+ (ftrace_ops_list->next == &ftrace_list_end &&
+ !(ftrace_ops_list->flags & FTRACE_OPS_FL_DYNAMIC)))
+ func = ftrace_ops_list->func;
+ else
+ func = ftrace_ops_list_func;
- /*
- * For one func, simply call it directly.
- * For more than one func, call the chain.
- */
#ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST
- ftrace_trace_function = func;
+ ftrace_trace_function = func;
#else
- __ftrace_trace_function = func;
- ftrace_trace_function = ftrace_test_stop_func;
+ __ftrace_trace_function = func;
+ ftrace_trace_function = ftrace_test_stop_func;
#endif
- }
+}
- return 0;
+static void add_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops)
+{
+ ops->next = *list;
+ /*
+ * We are entering ops into the list but another
+ * CPU might be walking that list. We need to make sure
+ * the ops->next pointer is valid before another CPU sees
+ * the ops pointer included into the list.
+ */
+ rcu_assign_pointer(*list, ops);
}
-static int __unregister_ftrace_function(struct ftrace_ops *ops)
+static int remove_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops)
{
struct ftrace_ops **p;
@@ -194,13 +229,12 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops)
* If we are removing the last function, then simply point
* to the ftrace_stub.
*/
- if (ftrace_list == ops && ops->next == &ftrace_list_end) {
- ftrace_trace_function = ftrace_stub;
- ftrace_list = &ftrace_list_end;
+ if (*list == ops && ops->next == &ftrace_list_end) {
+ *list = &ftrace_list_end;
return 0;
}
- for (p = &ftrace_list; *p != &ftrace_list_end; p = &(*p)->next)
+ for (p = list; *p != &ftrace_list_end; p = &(*p)->next)
if (*p == ops)
break;
@@ -208,53 +242,83 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops)
return -1;
*p = (*p)->next;
+ return 0;
+}
- if (ftrace_enabled) {
- /* If we only have one func left, then call that directly */
- if (ftrace_list->next == &ftrace_list_end) {
- ftrace_func_t func = ftrace_list->func;
+static int __register_ftrace_function(struct ftrace_ops *ops)
+{
+ if (ftrace_disabled)
+ return -ENODEV;
- if (!list_empty(&ftrace_pids)) {
- set_ftrace_pid_function(func);
- func = ftrace_pid_func;
- }
-#ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST
- ftrace_trace_function = func;
-#else
- __ftrace_trace_function = func;
-#endif
- }
- }
+ if (FTRACE_WARN_ON(ops == &global_ops))
+ return -EINVAL;
+
+ if (WARN_ON(ops->flags & FTRACE_OPS_FL_ENABLED))
+ return -EBUSY;
+
+ if (!core_kernel_data((unsigned long)ops))
+ ops->flags |= FTRACE_OPS_FL_DYNAMIC;
+
+ if (ops->flags & FTRACE_OPS_FL_GLOBAL) {
+ int first = ftrace_global_list == &ftrace_list_end;
+ add_ftrace_ops(&ftrace_global_list, ops);
+ ops->flags |= FTRACE_OPS_FL_ENABLED;
+ if (first)
+ add_ftrace_ops(&ftrace_ops_list, &global_ops);
+ } else
+ add_ftrace_ops(&ftrace_ops_list, ops);
+
+ if (ftrace_enabled)
+ update_ftrace_function();
return 0;
}
-static void ftrace_update_pid_func(void)
+static int __unregister_ftrace_function(struct ftrace_ops *ops)
{
- ftrace_func_t func;
+ int ret;
- if (ftrace_trace_function == ftrace_stub)
- return;
+ if (ftrace_disabled)
+ return -ENODEV;
-#ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST
- func = ftrace_trace_function;
-#else
- func = __ftrace_trace_function;
-#endif
+ if (WARN_ON(!(ops->flags & FTRACE_OPS_FL_ENABLED)))
+ return -EBUSY;
- if (!list_empty(&ftrace_pids)) {
- set_ftrace_pid_function(func);
- func = ftrace_pid_func;
- } else {
- if (func == ftrace_pid_func)
- func = ftrace_pid_function;
- }
+ if (FTRACE_WARN_ON(ops == &global_ops))
+ return -EINVAL;
-#ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST
- ftrace_trace_function = func;
-#else
- __ftrace_trace_function = func;
-#endif
+ if (ops->flags & FTRACE_OPS_FL_GLOBAL) {
+ ret = remove_ftrace_ops(&ftrace_global_list, ops);
+ if (!ret && ftrace_global_list == &ftrace_list_end)
+ ret = remove_ftrace_ops(&ftrace_ops_list, &global_ops);
+ if (!ret)
+ ops->flags &= ~FTRACE_OPS_FL_ENABLED;
+ } else
+ ret = remove_ftrace_ops(&ftrace_ops_list, ops);
+
+ if (ret < 0)
+ return ret;
+
+ if (ftrace_enabled)
+ update_ftrace_function();
+
+ /*
+ * Dynamic ops may be freed, we must make sure that all
+ * callers are done before leaving this function.
+ */
+ if (ops->flags & FTRACE_OPS_FL_DYNAMIC)
+ synchronize_sched();
+
+ return 0;
+}
+
+static void ftrace_update_pid_func(void)
+{
+ /* Only do something if we are tracing something */
+ if (ftrace_trace_function == ftrace_stub)
+ return;
+
+ update_ftrace_function();
}
#ifdef CONFIG_FUNCTION_PROFILER
@@ -888,8 +952,35 @@ enum {
FTRACE_START_FUNC_RET = (1 << 3),
FTRACE_STOP_FUNC_RET = (1 << 4),
};
+struct ftrace_func_entry {
+ struct hlist_node hlist;
+ unsigned long ip;
+};
-static int ftrace_filtered;
+struct ftrace_hash {
+ unsigned long size_bits;
+ struct hlist_head *buckets;
+ unsigned long count;
+ struct rcu_head rcu;
+};
+
+/*
+ * We make these constant because no one should touch them,
+ * but they are used as the default "empty hash", to avoid allocating
+ * it all the time. These are in a read only section such that if
+ * anyone does try to modify it, it will cause an exception.
+ */
+static const struct hlist_head empty_buckets[1];
+static const struct ftrace_hash empty_hash = {
+ .buckets = (struct hlist_head *)empty_buckets,
+};
+#define EMPTY_HASH ((struct ftrace_hash *)&empty_hash)
+
+static struct ftrace_ops global_ops = {
+ .func = ftrace_stub,
+ .notrace_hash = EMPTY_HASH,
+ .filter_hash = EMPTY_HASH,
+};
static struct dyn_ftrace *ftrace_new_addrs;
@@ -912,6 +1003,269 @@ static struct ftrace_page *ftrace_pages;
static struct dyn_ftrace *ftrace_free_records;
+static struct ftrace_func_entry *
+ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip)
+{
+ unsigned long key;
+ struct ftrace_func_entry *entry;
+ struct hlist_head *hhd;
+ struct hlist_node *n;
+
+ if (!hash->count)
+ return NULL;
+
+ if (hash->size_bits > 0)
+ key = hash_long(ip, hash->size_bits);
+ else
+ key = 0;
+
+ hhd = &hash->buckets[key];
+
+ hlist_for_each_entry_rcu(entry, n, hhd, hlist) {
+ if (entry->ip == ip)
+ return entry;
+ }
+ return NULL;
+}
+
+static void __add_hash_entry(struct ftrace_hash *hash,
+ struct ftrace_func_entry *entry)
+{
+ struct hlist_head *hhd;
+ unsigned long key;
+
+ if (hash->size_bits)
+ key = hash_long(entry->ip, hash->size_bits);
+ else
+ key = 0;
+
+ hhd = &hash->buckets[key];
+ hlist_add_head(&entry->hlist, hhd);
+ hash->count++;
+}
+
+static int add_hash_entry(struct ftrace_hash *hash, unsigned long ip)
+{
+ struct ftrace_func_entry *entry;
+
+ entry = kmalloc(sizeof(*entry), GFP_KERNEL);
+ if (!entry)
+ return -ENOMEM;
+
+ entry->ip = ip;
+ __add_hash_entry(hash, entry);
+
+ return 0;
+}
+
+static void
+free_hash_entry(struct ftrace_hash *hash,
+ struct ftrace_func_entry *entry)
+{
+ hlist_del(&entry->hlist);
+ kfree(entry);
+ hash->count--;
+}
+
+static void
+remove_hash_entry(struct ftrace_hash *hash,
+ struct ftrace_func_entry *entry)
+{
+ hlist_del(&entry->hlist);
+ hash->count--;
+}
+
+static void ftrace_hash_clear(struct ftrace_hash *hash)
+{
+ struct hlist_head *hhd;
+ struct hlist_node *tp, *tn;
+ struct ftrace_func_entry *entry;
+ int size = 1 << hash->size_bits;
+ int i;
+
+ if (!hash->count)
+ return;
+
+ for (i = 0; i < size; i++) {
+ hhd = &hash->buckets[i];
+ hlist_for_each_entry_safe(entry, tp, tn, hhd, hlist)
+ free_hash_entry(hash, entry);
+ }
+ FTRACE_WARN_ON(hash->count);
+}
+
+static void free_ftrace_hash(struct ftrace_hash *hash)
+{
+ if (!hash || hash == EMPTY_HASH)
+ return;
+ ftrace_hash_clear(hash);
+ kfree(hash->buckets);
+ kfree(hash);
+}
+
+static void __free_ftrace_hash_rcu(struct rcu_head *rcu)
+{
+ struct ftrace_hash *hash;
+
+ hash = container_of(rcu, struct ftrace_hash, rcu);
+ free_ftrace_hash(hash);
+}
+
+static void free_ftrace_hash_rcu(struct ftrace_hash *hash)
+{
+ if (!hash || hash == EMPTY_HASH)
+ return;
+ call_rcu_sched(&hash->rcu, __free_ftrace_hash_rcu);
+}
+
+static struct ftrace_hash *alloc_ftrace_hash(int size_bits)
+{
+ struct ftrace_hash *hash;
+ int size;
+
+ hash = kzalloc(sizeof(*hash), GFP_KERNEL);
+ if (!hash)
+ return NULL;
+
+ size = 1 << size_bits;
+ hash->buckets = kzalloc(sizeof(*hash->buckets) * size, GFP_KERNEL);
+
+ if (!hash->buckets) {
+ kfree(hash);
+ return NULL;
+ }
+
+ hash->size_bits = size_bits;
+
+ return hash;
+}
+
+static struct ftrace_hash *
+alloc_and_copy_ftrace_hash(int size_bits, struct ftrace_hash *hash)
+{
+ struct ftrace_func_entry *entry;
+ struct ftrace_hash *new_hash;
+ struct hlist_node *tp;
+ int size;
+ int ret;
+ int i;
+
+ new_hash = alloc_ftrace_hash(size_bits);
+ if (!new_hash)
+ return NULL;
+
+ /* Empty hash? */
+ if (!hash || !hash->count)
+ return new_hash;
+
+ size = 1 << hash->size_bits;
+ for (i = 0; i < size; i++) {
+ hlist_for_each_entry(entry, tp, &hash->buckets[i], hlist) {
+ ret = add_hash_entry(new_hash, entry->ip);
+ if (ret < 0)
+ goto free_hash;
+ }
+ }
+
+ FTRACE_WARN_ON(new_hash->count != hash->count);
+
+ return new_hash;
+
+ free_hash:
+ free_ftrace_hash(new_hash);
+ return NULL;
+}
+
+static int
+ftrace_hash_move(struct ftrace_hash **dst, struct ftrace_hash *src)
+{
+ struct ftrace_func_entry *entry;
+ struct hlist_node *tp, *tn;
+ struct hlist_head *hhd;
+ struct ftrace_hash *old_hash;
+ struct ftrace_hash *new_hash;
+ unsigned long key;
+ int size = src->count;
+ int bits = 0;
+ int i;
+
+ /*
+ * If the new source is empty, just free dst and assign it
+ * the empty_hash.
+ */
+ if (!src->count) {
+ free_ftrace_hash_rcu(*dst);
+ rcu_assign_pointer(*dst, EMPTY_HASH);
+ return 0;
+ }
+
+ /*
+ * Make the hash size about 1/2 the # found
+ */
+ for (size /= 2; size; size >>= 1)
+ bits++;
+
+ /* Don't allocate too much */
+ if (bits > FTRACE_HASH_MAX_BITS)
+ bits = FTRACE_HASH_MAX_BITS;
+
+ new_hash = alloc_ftrace_hash(bits);
+ if (!new_hash)
+ return -ENOMEM;
+
+ size = 1 << src->size_bits;
+ for (i = 0; i < size; i++) {
+ hhd = &src->buckets[i];
+ hlist_for_each_entry_safe(entry, tp, tn, hhd, hlist) {
+ if (bits > 0)
+ key = hash_long(entry->ip, bits);
+ else
+ key = 0;
+ remove_hash_entry(src, entry);
+ __add_hash_entry(new_hash, entry);
+ }
+ }
+
+ old_hash = *dst;
+ rcu_assign_pointer(*dst, new_hash);
+ free_ftrace_hash_rcu(old_hash);
+
+ return 0;
+}
+
+/*
+ * Test the hashes for this ops to see if we want to call
+ * the ops->func or not.
+ *
+ * It's a match if the ip is in the ops->filter_hash or
+ * the filter_hash does not exist or is empty,
+ * AND
+ * the ip is not in the ops->notrace_hash.
+ *
+ * This needs to be called with preemption disabled as
+ * the hashes are freed with call_rcu_sched().
+ */
+static int
+ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip)
+{
+ struct ftrace_hash *filter_hash;
+ struct ftrace_hash *notrace_hash;
+ int ret;
+
+ filter_hash = rcu_dereference_raw(ops->filter_hash);
+ notrace_hash = rcu_dereference_raw(ops->notrace_hash);
+
+ if ((!filter_hash || !filter_hash->count ||
+ ftrace_lookup_ip(filter_hash, ip)) &&
+ (!notrace_hash || !notrace_hash->count ||
+ !ftrace_lookup_ip(notrace_hash, ip)))
+ ret = 1;
+ else
+ ret = 0;
+
+ return ret;
+}
+
/*
* This is a double for. Do not use 'break' to break out of the loop,
* you must use a goto.
@@ -926,6 +1280,105 @@ static struct dyn_ftrace *ftrace_free_records;
} \
}
+static void __ftrace_hash_rec_update(struct ftrace_ops *ops,
+ int filter_hash,
+ bool inc)
+{
+ struct ftrace_hash *hash;
+ struct ftrace_hash *other_hash;
+ struct ftrace_page *pg;
+ struct dyn_ftrace *rec;
+ int count = 0;
+ int all = 0;
+
+ /* Only update if the ops has been registered */
+ if (!(ops->flags & FTRACE_OPS_FL_ENABLED))
+ return;
+
+ /*
+ * In the filter_hash case:
+ * If the count is zero, we update all records.
+ * Otherwise we just update the items in the hash.
+ *
+ * In the notrace_hash case:
+ * We enable the update in the hash.
+ * As disabling notrace means enabling the tracing,
+ * and enabling notrace means disabling, the inc variable
+ * gets inversed.
+ */
+ if (filter_hash) {
+ hash = ops->filter_hash;
+ other_hash = ops->notrace_hash;
+ if (!hash || !hash->count)
+ all = 1;
+ } else {
+ inc = !inc;
+ hash = ops->notrace_hash;
+ other_hash = ops->filter_hash;
+ /*
+ * If the notrace hash has no items,
+ * then there's nothing to do.
+ */
+ if (hash && !hash->count)
+ return;
+ }
+
+ do_for_each_ftrace_rec(pg, rec) {
+ int in_other_hash = 0;
+ int in_hash = 0;
+ int match = 0;
+
+ if (all) {
+ /*
+ * Only the filter_hash affects all records.
+ * Update if the record is not in the notrace hash.
+ */
+ if (!other_hash || !ftrace_lookup_ip(other_hash, rec->ip))
+ match = 1;
+ } else {
+ in_hash = hash && !!ftrace_lookup_ip(hash, rec->ip);
+ in_other_hash = other_hash && !!ftrace_lookup_ip(other_hash, rec->ip);
+
+ /*
+ *
+ */
+ if (filter_hash && in_hash && !in_other_hash)
+ match = 1;
+ else if (!filter_hash && in_hash &&
+ (in_other_hash || !other_hash->count))
+ match = 1;
+ }
+ if (!match)
+ continue;
+
+ if (inc) {
+ rec->flags++;
+ if (FTRACE_WARN_ON((rec->flags & ~FTRACE_FL_MASK) == FTRACE_REF_MAX))
+ return;
+ } else {
+ if (FTRACE_WARN_ON((rec->flags & ~FTRACE_FL_MASK) == 0))
+ return;
+ rec->flags--;
+ }
+ count++;
+ /* Shortcut, if we handled all records, we are done. */
+ if (!all && count == hash->count)
+ return;
+ } while_for_each_ftrace_rec();
+}
+
+static void ftrace_hash_rec_disable(struct ftrace_ops *ops,
+ int filter_hash)
+{
+ __ftrace_hash_rec_update(ops, filter_hash, 0);
+}
+
+static void ftrace_hash_rec_enable(struct ftrace_ops *ops,
+ int filter_hash)
+{
+ __ftrace_hash_rec_update(ops, filter_hash, 1);
+}
+
static void ftrace_free_rec(struct dyn_ftrace *rec)
{
rec->freelist = ftrace_free_records;
@@ -1047,18 +1500,18 @@ __ftrace_replace_code(struct dyn_ftrace *rec, int enable)
ftrace_addr = (unsigned long)FTRACE_ADDR;
/*
- * If this record is not to be traced or we want to disable it,
- * then disable it.
+ * If we are enabling tracing:
+ *
+ * If the record has a ref count, then we need to enable it
+ * because someone is using it.
*
- * If we want to enable it and filtering is off, then enable it.
+ * Otherwise we make sure its disabled.
*
- * If we want to enable it and filtering is on, enable it only if
- * it's filtered
+ * If we are disabling tracing, then disable all records that
+ * are enabled.
*/
- if (enable && !(rec->flags & FTRACE_FL_NOTRACE)) {
- if (!ftrace_filtered || (rec->flags & FTRACE_FL_FILTER))
- flag = FTRACE_FL_ENABLED;
- }
+ if (enable && (rec->flags & ~FTRACE_FL_MASK))
+ flag = FTRACE_FL_ENABLED;
/* If the state of this record hasn't changed, then do nothing */
if ((rec->flags & FTRACE_FL_ENABLED) == flag)
@@ -1079,19 +1532,16 @@ static void ftrace_replace_code(int enable)
struct ftrace_page *pg;
int failed;
+ if (unlikely(ftrace_disabled))
+ return;
+
do_for_each_ftrace_rec(pg, rec) {
- /*
- * Skip over free records, records that have
- * failed and not converted.
- */
- if (rec->flags & FTRACE_FL_FREE ||
- rec->flags & FTRACE_FL_FAILED ||
- !(rec->flags & FTRACE_FL_CONVERTED))
+ /* Skip over free records */
+ if (rec->flags & FTRACE_FL_FREE)
continue;
failed = __ftrace_replace_code(rec, enable);
if (failed) {
- rec->flags |= FTRACE_FL_FAILED;
ftrace_bug(failed, rec->ip);
/* Stop processing */
return;
@@ -1107,10 +1557,12 @@ ftrace_code_disable(struct module *mod, struct dyn_ftrace *rec)
ip = rec->ip;
+ if (unlikely(ftrace_disabled))
+ return 0;
+
ret = ftrace_make_nop(mod, rec, MCOUNT_ADDR);
if (ret) {
ftrace_bug(ret, ip);
- rec->flags |= FTRACE_FL_FAILED;
return 0;
}
return 1;
@@ -1171,6 +1623,7 @@ static void ftrace_run_update_code(int command)
static ftrace_func_t saved_ftrace_func;
static int ftrace_start_up;
+static int global_start_up;
static void ftrace_startup_enable(int command)
{
@@ -1185,19 +1638,36 @@ static void ftrace_startup_enable(int command)
ftrace_run_update_code(command);
}
-static void ftrace_startup(int command)
+static void ftrace_startup(struct ftrace_ops *ops, int command)
{
+ bool hash_enable = true;
+
if (unlikely(ftrace_disabled))
return;
ftrace_start_up++;
command |= FTRACE_ENABLE_CALLS;
+ /* ops marked global share the filter hashes */
+ if (ops->flags & FTRACE_OPS_FL_GLOBAL) {
+ ops = &global_ops;
+ /* Don't update hash if global is already set */
+ if (global_start_up)
+ hash_enable = false;
+ global_start_up++;
+ }
+
+ ops->flags |= FTRACE_OPS_FL_ENABLED;
+ if (hash_enable)
+ ftrace_hash_rec_enable(ops, 1);
+
ftrace_startup_enable(command);
}
-static void ftrace_shutdown(int command)
+static void ftrace_shutdown(struct ftrace_ops *ops, int command)
{
+ bool hash_disable = true;
+
if (unlikely(ftrace_disabled))
return;
@@ -1209,6 +1679,23 @@ static void ftrace_shutdown(int command)
*/
WARN_ON_ONCE(ftrace_start_up < 0);
+ if (ops->flags & FTRACE_OPS_FL_GLOBAL) {
+ ops = &global_ops;
+ global_start_up--;
+ WARN_ON_ONCE(global_start_up < 0);
+ /* Don't update hash if global still has users */
+ if (global_start_up) {
+ WARN_ON_ONCE(!ftrace_start_up);
+ hash_disable = false;
+ }
+ }
+
+ if (hash_disable)
+ ftrace_hash_rec_disable(ops, 1);
+
+ if (ops != &global_ops || !global_start_up)
+ ops->flags &= ~FTRACE_OPS_FL_ENABLED;
+
if (!ftrace_start_up)
command |= FTRACE_DISABLE_CALLS;
@@ -1273,10 +1760,10 @@ static int ftrace_update_code(struct module *mod)
*/
if (!ftrace_code_disable(mod, p)) {
ftrace_free_rec(p);
- continue;
+ /* Game over */
+ break;
}
- p->flags |= FTRACE_FL_CONVERTED;
ftrace_update_cnt++;
/*
@@ -1351,9 +1838,9 @@ static int __init ftrace_dyn_table_alloc(unsigned long num_to_init)
enum {
FTRACE_ITER_FILTER = (1 << 0),
FTRACE_ITER_NOTRACE = (1 << 1),
- FTRACE_ITER_FAILURES = (1 << 2),
- FTRACE_ITER_PRINTALL = (1 << 3),
- FTRACE_ITER_HASH = (1 << 4),
+ FTRACE_ITER_PRINTALL = (1 << 2),
+ FTRACE_ITER_HASH = (1 << 3),
+ FTRACE_ITER_ENABLED = (1 << 4),
};
#define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */
@@ -1365,6 +1852,8 @@ struct ftrace_iterator {
struct dyn_ftrace *func;
struct ftrace_func_probe *probe;
struct trace_parser parser;
+ struct ftrace_hash *hash;
+ struct ftrace_ops *ops;
int hidx;
int idx;
unsigned flags;
@@ -1461,8 +1950,12 @@ static void *
t_next(struct seq_file *m, void *v, loff_t *pos)
{
struct ftrace_iterator *iter = m->private;
+ struct ftrace_ops *ops = &global_ops;
struct dyn_ftrace *rec = NULL;
+ if (unlikely(ftrace_disabled))
+ return NULL;
+
if (iter->flags & FTRACE_ITER_HASH)
return t_hash_next(m, pos);
@@ -1483,17 +1976,15 @@ t_next(struct seq_file *m, void *v, loff_t *pos)
rec = &iter->pg->records[iter->idx++];
if ((rec->flags & FTRACE_FL_FREE) ||
- (!(iter->flags & FTRACE_ITER_FAILURES) &&
- (rec->flags & FTRACE_FL_FAILED)) ||
-
- ((iter->flags & FTRACE_ITER_FAILURES) &&
- !(rec->flags & FTRACE_FL_FAILED)) ||
-
((iter->flags & FTRACE_ITER_FILTER) &&
- !(rec->flags & FTRACE_FL_FILTER)) ||
+ !(ftrace_lookup_ip(ops->filter_hash, rec->ip))) ||
((iter->flags & FTRACE_ITER_NOTRACE) &&
- !(rec->flags & FTRACE_FL_NOTRACE))) {
+ !ftrace_lookup_ip(ops->notrace_hash, rec->ip)) ||
+
+ ((iter->flags & FTRACE_ITER_ENABLED) &&
+ !(rec->flags & ~FTRACE_FL_MASK))) {
+
rec = NULL;
goto retry;
}
@@ -1517,10 +2008,15 @@ static void reset_iter_read(struct ftrace_iterator *iter)
static void *t_start(struct seq_file *m, loff_t *pos)
{
struct ftrace_iterator *iter = m->private;
+ struct ftrace_ops *ops = &global_ops;
void *p = NULL;
loff_t l;
mutex_lock(&ftrace_lock);
+
+ if (unlikely(ftrace_disabled))
+ return NULL;
+
/*
* If an lseek was done, then reset and start from beginning.
*/
@@ -1532,7 +2028,7 @@ static void *t_start(struct seq_file *m, loff_t *pos)
* off, we can short cut and just print out that all
* functions are enabled.
*/
- if (iter->flags & FTRACE_ITER_FILTER && !ftrace_filtered) {
+ if (iter->flags & FTRACE_ITER_FILTER && !ops->filter_hash->count) {
if (*pos > 0)
return t_hash_start(m, pos);
iter->flags |= FTRACE_ITER_PRINTALL;
@@ -1590,7 +2086,11 @@ static int t_show(struct seq_file *m, void *v)
if (!rec)
return 0;
- seq_printf(m, "%ps\n", (void *)rec->ip);
+ seq_printf(m, "%ps", (void *)rec->ip);
+ if (iter->flags & FTRACE_ITER_ENABLED)
+ seq_printf(m, " (%ld)",
+ rec->flags & ~FTRACE_FL_MASK);
+ seq_printf(m, "\n");
return 0;
}
@@ -1630,44 +2130,46 @@ ftrace_avail_open(struct inode *inode, struct file *file)
}
static int
-ftrace_failures_open(struct inode *inode, struct file *file)
+ftrace_enabled_open(struct inode *inode, struct file *file)
{
- int ret;
- struct seq_file *m;
struct ftrace_iterator *iter;
+ int ret;
+
+ if (unlikely(ftrace_disabled))
+ return -ENODEV;
+
+ iter = kzalloc(sizeof(*iter), GFP_KERNEL);
+ if (!iter)
+ return -ENOMEM;
+
+ iter->pg = ftrace_pages_start;
+ iter->flags = FTRACE_ITER_ENABLED;
- ret = ftrace_avail_open(inode, file);
+ ret = seq_open(file, &show_ftrace_seq_ops);
if (!ret) {
- m = file->private_data;
- iter = m->private;
- iter->flags = FTRACE_ITER_FAILURES;
+ struct seq_file *m = file->private_data;
+
+ m->private = iter;
+ } else {
+ kfree(iter);
}
return ret;
}
-
-static void ftrace_filter_reset(int enable)
+static void ftrace_filter_reset(struct ftrace_hash *hash)
{
- struct ftrace_page *pg;
- struct dyn_ftrace *rec;
- unsigned long type = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
-
mutex_lock(&ftrace_lock);
- if (enable)
- ftrace_filtered = 0;
- do_for_each_ftrace_rec(pg, rec) {
- if (rec->flags & FTRACE_FL_FAILED)
- continue;
- rec->flags &= ~type;
- } while_for_each_ftrace_rec();
+ ftrace_hash_clear(hash);
mutex_unlock(&ftrace_lock);
}
static int
-ftrace_regex_open(struct inode *inode, struct file *file, int enable)
+ftrace_regex_open(struct ftrace_ops *ops, int flag,
+ struct inode *inode, struct file *file)
{
struct ftrace_iterator *iter;
+ struct ftrace_hash *hash;
int ret = 0;
if (unlikely(ftrace_disabled))
@@ -1682,21 +2184,42 @@ ftrace_regex_open(struct inode *inode, struct file *file, int enable)
return -ENOMEM;
}
+ if (flag & FTRACE_ITER_NOTRACE)
+ hash = ops->notrace_hash;
+ else
+ hash = ops->filter_hash;
+
+ iter->ops = ops;
+ iter->flags = flag;
+
+ if (file->f_mode & FMODE_WRITE) {
+ mutex_lock(&ftrace_lock);
+ iter->hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, hash);
+ mutex_unlock(&ftrace_lock);
+
+ if (!iter->hash) {
+ trace_parser_put(&iter->parser);
+ kfree(iter);
+ return -ENOMEM;
+ }
+ }
+
mutex_lock(&ftrace_regex_lock);
+
if ((file->f_mode & FMODE_WRITE) &&
(file->f_flags & O_TRUNC))
- ftrace_filter_reset(enable);
+ ftrace_filter_reset(iter->hash);
if (file->f_mode & FMODE_READ) {
iter->pg = ftrace_pages_start;
- iter->flags = enable ? FTRACE_ITER_FILTER :
- FTRACE_ITER_NOTRACE;
ret = seq_open(file, &show_ftrace_seq_ops);
if (!ret) {
struct seq_file *m = file->private_data;
m->private = iter;
} else {
+ /* Failed */
+ free_ftrace_hash(iter->hash);
trace_parser_put(&iter->parser);
kfree(iter);
}
@@ -1710,13 +2233,15 @@ ftrace_regex_open(struct inode *inode, struct file *file, int enable)
static int
ftrace_filter_open(struct inode *inode, struct file *file)
{
- return ftrace_regex_open(inode, file, 1);
+ return ftrace_regex_open(&global_ops, FTRACE_ITER_FILTER,
+ inode, file);
}
static int
ftrace_notrace_open(struct inode *inode, struct file *file)
{
- return ftrace_regex_open(inode, file, 0);
+ return ftrace_regex_open(&global_ops, FTRACE_ITER_NOTRACE,
+ inode, file);
}
static loff_t
@@ -1761,86 +2286,99 @@ static int ftrace_match(char *str, char *regex, int len, int type)
}
static int
-ftrace_match_record(struct dyn_ftrace *rec, char *regex, int len, int type)
+enter_record(struct ftrace_hash *hash, struct dyn_ftrace *rec, int not)
+{
+ struct ftrace_func_entry *entry;
+ int ret = 0;
+
+ entry = ftrace_lookup_ip(hash, rec->ip);
+ if (not) {
+ /* Do nothing if it doesn't exist */
+ if (!entry)
+ return 0;
+
+ free_hash_entry(hash, entry);
+ } else {
+ /* Do nothing if it exists */
+ if (entry)
+ return 0;
+
+ ret = add_hash_entry(hash, rec->ip);
+ }
+ return ret;
+}
+
+static int
+ftrace_match_record(struct dyn_ftrace *rec, char *mod,
+ char *regex, int len, int type)
{
char str[KSYM_SYMBOL_LEN];
+ char *modname;
+
+ kallsyms_lookup(rec->ip, NULL, NULL, &modname, str);
+
+ if (mod) {
+ /* module lookup requires matching the module */
+ if (!modname || strcmp(modname, mod))
+ return 0;
+
+ /* blank search means to match all funcs in the mod */
+ if (!len)
+ return 1;
+ }
- kallsyms_lookup(rec->ip, NULL, NULL, NULL, str);
return ftrace_match(str, regex, len, type);
}
-static int ftrace_match_records(char *buff, int len, int enable)
+static int
+match_records(struct ftrace_hash *hash, char *buff,
+ int len, char *mod, int not)
{
- unsigned int search_len;
+ unsigned search_len = 0;
struct ftrace_page *pg;
struct dyn_ftrace *rec;
- unsigned long flag;
- char *search;
- int type;
- int not;
+ int type = MATCH_FULL;
+ char *search = buff;
int found = 0;
+ int ret;
- flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
- type = filter_parse_regex(buff, len, &search, &not);
-
- search_len = strlen(search);
+ if (len) {
+ type = filter_parse_regex(buff, len, &search, &not);
+ search_len = strlen(search);
+ }
mutex_lock(&ftrace_lock);
- do_for_each_ftrace_rec(pg, rec) {
- if (rec->flags & FTRACE_FL_FAILED)
- continue;
+ if (unlikely(ftrace_disabled))
+ goto out_unlock;
- if (ftrace_match_record(rec, search, search_len, type)) {
- if (not)
- rec->flags &= ~flag;
- else
- rec->flags |= flag;
+ do_for_each_ftrace_rec(pg, rec) {
+
+ if (ftrace_match_record(rec, mod, search, search_len, type)) {
+ ret = enter_record(hash, rec, not);
+ if (ret < 0) {
+ found = ret;
+ goto out_unlock;
+ }
found = 1;
}
- /*
- * Only enable filtering if we have a function that
- * is filtered on.
- */
- if (enable && (rec->flags & FTRACE_FL_FILTER))
- ftrace_filtered = 1;
} while_for_each_ftrace_rec();
+ out_unlock:
mutex_unlock(&ftrace_lock);
return found;
}
static int
-ftrace_match_module_record(struct dyn_ftrace *rec, char *mod,
- char *regex, int len, int type)
+ftrace_match_records(struct ftrace_hash *hash, char *buff, int len)
{
- char str[KSYM_SYMBOL_LEN];
- char *modname;
-
- kallsyms_lookup(rec->ip, NULL, NULL, &modname, str);
-
- if (!modname || strcmp(modname, mod))
- return 0;
-
- /* blank search means to match all funcs in the mod */
- if (len)
- return ftrace_match(str, regex, len, type);
- else
- return 1;
+ return match_records(hash, buff, len, NULL, 0);
}
-static int ftrace_match_module_records(char *buff, char *mod, int enable)
+static int
+ftrace_match_module_records(struct ftrace_hash *hash, char *buff, char *mod)
{
- unsigned search_len = 0;
- struct ftrace_page *pg;
- struct dyn_ftrace *rec;
- int type = MATCH_FULL;
- char *search = buff;
- unsigned long flag;
int not = 0;
- int found = 0;
-
- flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
/* blank or '*' mean the same */
if (strcmp(buff, "*") == 0)
@@ -1852,32 +2390,7 @@ static int ftrace_match_module_records(char *buff, char *mod, int enable)
not = 1;
}
- if (strlen(buff)) {
- type = filter_parse_regex(buff, strlen(buff), &search, &not);
- search_len = strlen(search);
- }
-
- mutex_lock(&ftrace_lock);
- do_for_each_ftrace_rec(pg, rec) {
-
- if (rec->flags & FTRACE_FL_FAILED)
- continue;
-
- if (ftrace_match_module_record(rec, mod,
- search, search_len, type)) {
- if (not)
- rec->flags &= ~flag;
- else
- rec->flags |= flag;
- found = 1;
- }
- if (enable && (rec->flags & FTRACE_FL_FILTER))
- ftrace_filtered = 1;
-
- } while_for_each_ftrace_rec();
- mutex_unlock(&ftrace_lock);
-
- return found;
+ return match_records(hash, buff, strlen(buff), mod, not);
}
/*
@@ -1888,7 +2401,10 @@ static int ftrace_match_module_records(char *buff, char *mod, int enable)
static int
ftrace_mod_callback(char *func, char *cmd, char *param, int enable)
{
+ struct ftrace_ops *ops = &global_ops;
+ struct ftrace_hash *hash;
char *mod;
+ int ret = -EINVAL;
/*
* cmd == 'mod' because we only registered this func
@@ -1900,15 +2416,24 @@ ftrace_mod_callback(char *func, char *cmd, char *param, int enable)
/* we must have a module name */
if (!param)
- return -EINVAL;
+ return ret;
mod = strsep(&param, ":");
if (!strlen(mod))
- return -EINVAL;
+ return ret;
- if (ftrace_match_module_records(func, mod, enable))
- return 0;
- return -EINVAL;
+ if (enable)
+ hash = ops->filter_hash;
+ else
+ hash = ops->notrace_hash;
+
+ ret = ftrace_match_module_records(hash, func, mod);
+ if (!ret)
+ ret = -EINVAL;
+ if (ret < 0)
+ return ret;
+
+ return 0;
}
static struct ftrace_func_command ftrace_mod_cmd = {
@@ -1959,6 +2484,7 @@ static int ftrace_probe_registered;
static void __enable_ftrace_function_probe(void)
{
+ int ret;
int i;
if (ftrace_probe_registered)
@@ -1973,13 +2499,16 @@ static void __enable_ftrace_function_probe(void)
if (i == FTRACE_FUNC_HASHSIZE)
return;
- __register_ftrace_function(&trace_probe_ops);
- ftrace_startup(0);
+ ret = __register_ftrace_function(&trace_probe_ops);
+ if (!ret)
+ ftrace_startup(&trace_probe_ops, 0);
+
ftrace_probe_registered = 1;
}
static void __disable_ftrace_function_probe(void)
{
+ int ret;
int i;
if (!ftrace_probe_registered)
@@ -1992,8 +2521,10 @@ static void __disable_ftrace_function_probe(void)
}
/* no more funcs left */
- __unregister_ftrace_function(&trace_probe_ops);
- ftrace_shutdown(0);
+ ret = __unregister_ftrace_function(&trace_probe_ops);
+ if (!ret)
+ ftrace_shutdown(&trace_probe_ops, 0);
+
ftrace_probe_registered = 0;
}
@@ -2029,12 +2560,13 @@ register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
return -EINVAL;
mutex_lock(&ftrace_lock);
- do_for_each_ftrace_rec(pg, rec) {
- if (rec->flags & FTRACE_FL_FAILED)
- continue;
+ if (unlikely(ftrace_disabled))
+ goto out_unlock;
+
+ do_for_each_ftrace_rec(pg, rec) {
- if (!ftrace_match_record(rec, search, len, type))
+ if (!ftrace_match_record(rec, NULL, search, len, type))
continue;
entry = kmalloc(sizeof(*entry), GFP_KERNEL);
@@ -2195,18 +2727,22 @@ int unregister_ftrace_command(struct ftrace_func_command *cmd)
return ret;
}
-static int ftrace_process_regex(char *buff, int len, int enable)
+static int ftrace_process_regex(struct ftrace_hash *hash,
+ char *buff, int len, int enable)
{
char *func, *command, *next = buff;
struct ftrace_func_command *p;
- int ret = -EINVAL;
+ int ret;
func = strsep(&next, ":");
if (!next) {
- if (ftrace_match_records(func, len, enable))
- return 0;
- return ret;
+ ret = ftrace_match_records(hash, func, len);
+ if (!ret)
+ ret = -EINVAL;
+ if (ret < 0)
+ return ret;
+ return 0;
}
/* command found */
@@ -2239,6 +2775,10 @@ ftrace_regex_write(struct file *file, const char __user *ubuf,
mutex_lock(&ftrace_regex_lock);
+ ret = -ENODEV;
+ if (unlikely(ftrace_disabled))
+ goto out_unlock;
+
if (file->f_mode & FMODE_READ) {
struct seq_file *m = file->private_data;
iter = m->private;
@@ -2250,7 +2790,7 @@ ftrace_regex_write(struct file *file, const char __user *ubuf,
if (read >= 0 && trace_parser_loaded(parser) &&
!trace_parser_cont(parser)) {
- ret = ftrace_process_regex(parser->buffer,
+ ret = ftrace_process_regex(iter->hash, parser->buffer,
parser->idx, enable);
trace_parser_clear(parser);
if (ret)
@@ -2278,22 +2818,49 @@ ftrace_notrace_write(struct file *file, const char __user *ubuf,
return ftrace_regex_write(file, ubuf, cnt, ppos, 0);
}
-static void
-ftrace_set_regex(unsigned char *buf, int len, int reset, int enable)
+static int
+ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len,
+ int reset, int enable)
{
+ struct ftrace_hash **orig_hash;
+ struct ftrace_hash *hash;
+ int ret;
+
+ /* All global ops uses the global ops filters */
+ if (ops->flags & FTRACE_OPS_FL_GLOBAL)
+ ops = &global_ops;
+
if (unlikely(ftrace_disabled))
- return;
+ return -ENODEV;
+
+ if (enable)
+ orig_hash = &ops->filter_hash;
+ else
+ orig_hash = &ops->notrace_hash;
+
+ hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash);
+ if (!hash)
+ return -ENOMEM;
mutex_lock(&ftrace_regex_lock);
if (reset)
- ftrace_filter_reset(enable);
+ ftrace_filter_reset(hash);
if (buf)
- ftrace_match_records(buf, len, enable);
+ ftrace_match_records(hash, buf, len);
+
+ mutex_lock(&ftrace_lock);
+ ret = ftrace_hash_move(orig_hash, hash);
+ mutex_unlock(&ftrace_lock);
+
mutex_unlock(&ftrace_regex_lock);
+
+ free_ftrace_hash(hash);
+ return ret;
}
/**
* ftrace_set_filter - set a function to filter on in ftrace
+ * @ops - the ops to set the filter with
* @buf - the string that holds the function filter text.
* @len - the length of the string.
* @reset - non zero to reset all filters before applying this filter.
@@ -2301,13 +2868,16 @@ ftrace_set_regex(unsigned char *buf, int len, int reset, int enable)
* Filters denote which functions should be enabled when tracing is enabled.
* If @buf is NULL and reset is set, all functions will be enabled for tracing.
*/
-void ftrace_set_filter(unsigned char *buf, int len, int reset)
+void ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
+ int len, int reset)
{
- ftrace_set_regex(buf, len, reset, 1);
+ ftrace_set_regex(ops, buf, len, reset, 1);
}
+EXPORT_SYMBOL_GPL(ftrace_set_filter);
/**
* ftrace_set_notrace - set a function to not trace in ftrace
+ * @ops - the ops to set the notrace filter with
* @buf - the string that holds the function notrace text.
* @len - the length of the string.
* @reset - non zero to reset all filters before applying this filter.
@@ -2316,10 +2886,44 @@ void ftrace_set_filter(unsigned char *buf, int len, int reset)
* is enabled. If @buf is NULL and reset is set, all functions will be enabled
* for tracing.
*/
-void ftrace_set_notrace(unsigned char *buf, int len, int reset)
+void ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
+ int len, int reset)
{
- ftrace_set_regex(buf, len, reset, 0);
+ ftrace_set_regex(ops, buf, len, reset, 0);
}
+EXPORT_SYMBOL_GPL(ftrace_set_notrace);
+/**
+ * ftrace_set_filter - set a function to filter on in ftrace
+ * @ops - the ops to set the filter with
+ * @buf - the string that holds the function filter text.
+ * @len - the length of the string.
+ * @reset - non zero to reset all filters before applying this filter.
+ *
+ * Filters denote which functions should be enabled when tracing is enabled.
+ * If @buf is NULL and reset is set, all functions will be enabled for tracing.
+ */
+void ftrace_set_global_filter(unsigned char *buf, int len, int reset)
+{
+ ftrace_set_regex(&global_ops, buf, len, reset, 1);
+}
+EXPORT_SYMBOL_GPL(ftrace_set_global_filter);
+
+/**
+ * ftrace_set_notrace - set a function to not trace in ftrace
+ * @ops - the ops to set the notrace filter with
+ * @buf - the string that holds the function notrace text.
+ * @len - the length of the string.
+ * @reset - non zero to reset all filters before applying this filter.
+ *
+ * Notrace Filters denote which functions should not be enabled when tracing
+ * is enabled. If @buf is NULL and reset is set, all functions will be enabled
+ * for tracing.
+ */
+void ftrace_set_global_notrace(unsigned char *buf, int len, int reset)
+{
+ ftrace_set_regex(&global_ops, buf, len, reset, 0);
+}
+EXPORT_SYMBOL_GPL(ftrace_set_global_notrace);
/*
* command line interface to allow users to set filters on boot up.
@@ -2370,22 +2974,23 @@ static void __init set_ftrace_early_graph(char *buf)
}
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
-static void __init set_ftrace_early_filter(char *buf, int enable)
+static void __init
+set_ftrace_early_filter(struct ftrace_ops *ops, char *buf, int enable)
{
char *func;
while (buf) {
func = strsep(&buf, ",");
- ftrace_set_regex(func, strlen(func), 0, enable);
+ ftrace_set_regex(ops, func, strlen(func), 0, enable);
}
}
static void __init set_ftrace_early_filters(void)
{
if (ftrace_filter_buf[0])
- set_ftrace_early_filter(ftrace_filter_buf, 1);
+ set_ftrace_early_filter(&global_ops, ftrace_filter_buf, 1);
if (ftrace_notrace_buf[0])
- set_ftrace_early_filter(ftrace_notrace_buf, 0);
+ set_ftrace_early_filter(&global_ops, ftrace_notrace_buf, 0);
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
if (ftrace_graph_buf[0])
set_ftrace_early_graph(ftrace_graph_buf);
@@ -2393,11 +2998,14 @@ static void __init set_ftrace_early_filters(void)
}
static int
-ftrace_regex_release(struct inode *inode, struct file *file, int enable)
+ftrace_regex_release(struct inode *inode, struct file *file)
{
struct seq_file *m = (struct seq_file *)file->private_data;
struct ftrace_iterator *iter;
+ struct ftrace_hash **orig_hash;
struct trace_parser *parser;
+ int filter_hash;
+ int ret;
mutex_lock(&ftrace_regex_lock);
if (file->f_mode & FMODE_READ) {
@@ -2410,33 +3018,41 @@ ftrace_regex_release(struct inode *inode, struct file *file, int enable)
parser = &iter->parser;
if (trace_parser_loaded(parser)) {
parser->buffer[parser->idx] = 0;
- ftrace_match_records(parser->buffer, parser->idx, enable);
+ ftrace_match_records(iter->hash, parser->buffer, parser->idx);
}
- mutex_lock(&ftrace_lock);
- if (ftrace_start_up && ftrace_enabled)
- ftrace_run_update_code(FTRACE_ENABLE_CALLS);
- mutex_unlock(&ftrace_lock);
-
trace_parser_put(parser);
+
+ if (file->f_mode & FMODE_WRITE) {
+ filter_hash = !!(iter->flags & FTRACE_ITER_FILTER);
+
+ if (filter_hash)
+ orig_hash = &iter->ops->filter_hash;
+ else
+ orig_hash = &iter->ops->notrace_hash;
+
+ mutex_lock(&ftrace_lock);
+ /*
+ * Remove the current set, update the hash and add
+ * them back.
+ */
+ ftrace_hash_rec_disable(iter->ops, filter_hash);
+ ret = ftrace_hash_move(orig_hash, iter->hash);
+ if (!ret) {
+ ftrace_hash_rec_enable(iter->ops, filter_hash);
+ if (iter->ops->flags & FTRACE_OPS_FL_ENABLED
+ && ftrace_enabled)
+ ftrace_run_update_code(FTRACE_ENABLE_CALLS);
+ }
+ mutex_unlock(&ftrace_lock);
+ }
+ free_ftrace_hash(iter->hash);
kfree(iter);
mutex_unlock(&ftrace_regex_lock);
return 0;
}
-static int
-ftrace_filter_release(struct inode *inode, struct file *file)
-{
- return ftrace_regex_release(inode, file, 1);
-}
-
-static int
-ftrace_notrace_release(struct inode *inode, struct file *file)
-{
- return ftrace_regex_release(inode, file, 0);
-}
-
static const struct file_operations ftrace_avail_fops = {
.open = ftrace_avail_open,
.read = seq_read,
@@ -2444,8 +3060,8 @@ static const struct file_operations ftrace_avail_fops = {
.release = seq_release_private,
};
-static const struct file_operations ftrace_failures_fops = {
- .open = ftrace_failures_open,
+static const struct file_operations ftrace_enabled_fops = {
+ .open = ftrace_enabled_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release_private,
@@ -2456,7 +3072,7 @@ static const struct file_operations ftrace_filter_fops = {
.read = seq_read,
.write = ftrace_filter_write,
.llseek = ftrace_regex_lseek,
- .release = ftrace_filter_release,
+ .release = ftrace_regex_release,
};
static const struct file_operations ftrace_notrace_fops = {
@@ -2464,7 +3080,7 @@ static const struct file_operations ftrace_notrace_fops = {
.read = seq_read,
.write = ftrace_notrace_write,
.llseek = ftrace_regex_lseek,
- .release = ftrace_notrace_release,
+ .release = ftrace_regex_release,
};
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
@@ -2573,9 +3189,6 @@ ftrace_set_func(unsigned long *array, int *idx, char *buffer)
bool exists;
int i;
- if (ftrace_disabled)
- return -ENODEV;
-
/* decode regex */
type = filter_parse_regex(buffer, strlen(buffer), &search, &not);
if (!not && *idx >= FTRACE_GRAPH_MAX_FUNCS)
@@ -2584,12 +3197,18 @@ ftrace_set_func(unsigned long *array, int *idx, char *buffer)
search_len = strlen(search);
mutex_lock(&ftrace_lock);
+
+ if (unlikely(ftrace_disabled)) {
+ mutex_unlock(&ftrace_lock);
+ return -ENODEV;
+ }
+
do_for_each_ftrace_rec(pg, rec) {
- if (rec->flags & (FTRACE_FL_FAILED | FTRACE_FL_FREE))
+ if (rec->flags & FTRACE_FL_FREE)
continue;
- if (ftrace_match_record(rec, search, search_len, type)) {
+ if (ftrace_match_record(rec, NULL, search, search_len, type)) {
/* if it is in the array */
exists = false;
for (i = 0; i < *idx; i++) {
@@ -2679,8 +3298,8 @@ static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer)
trace_create_file("available_filter_functions", 0444,
d_tracer, NULL, &ftrace_avail_fops);
- trace_create_file("failures", 0444,
- d_tracer, NULL, &ftrace_failures_fops);
+ trace_create_file("enabled_functions", 0444,
+ d_tracer, NULL, &ftrace_enabled_fops);
trace_create_file("set_ftrace_filter", 0644, d_tracer,
NULL, &ftrace_filter_fops);
@@ -2703,7 +3322,6 @@ static int ftrace_process_locs(struct module *mod,
{
unsigned long *p;
unsigned long addr;
- unsigned long flags;
mutex_lock(&ftrace_lock);
p = start;
@@ -2720,10 +3338,7 @@ static int ftrace_process_locs(struct module *mod,
ftrace_record_ip(addr);
}
- /* disable interrupts to prevent kstop machine */
- local_irq_save(flags);
ftrace_update_code(mod);
- local_irq_restore(flags);
mutex_unlock(&ftrace_lock);
return 0;
@@ -2735,10 +3350,11 @@ void ftrace_release_mod(struct module *mod)
struct dyn_ftrace *rec;
struct ftrace_page *pg;
+ mutex_lock(&ftrace_lock);
+
if (ftrace_disabled)
- return;
+ goto out_unlock;
- mutex_lock(&ftrace_lock);
do_for_each_ftrace_rec(pg, rec) {
if (within_module_core(rec->ip, mod)) {
/*
@@ -2749,6 +3365,7 @@ void ftrace_release_mod(struct module *mod)
ftrace_free_rec(rec);
}
} while_for_each_ftrace_rec();
+ out_unlock:
mutex_unlock(&ftrace_lock);
}
@@ -2835,6 +3452,10 @@ void __init ftrace_init(void)
#else
+static struct ftrace_ops global_ops = {
+ .func = ftrace_stub,
+};
+
static int __init ftrace_nodyn_init(void)
{
ftrace_enabled = 1;
@@ -2845,12 +3466,38 @@ device_initcall(ftrace_nodyn_init);
static inline int ftrace_init_dyn_debugfs(struct dentry *d_tracer) { return 0; }
static inline void ftrace_startup_enable(int command) { }
/* Keep as macros so we do not need to define the commands */
-# define ftrace_startup(command) do { } while (0)
-# define ftrace_shutdown(command) do { } while (0)
+# define ftrace_startup(ops, command) do { } while (0)
+# define ftrace_shutdown(ops, command) do { } while (0)
# define ftrace_startup_sysctl() do { } while (0)
# define ftrace_shutdown_sysctl() do { } while (0)
+
+static inline int
+ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip)
+{
+ return 1;
+}
+
#endif /* CONFIG_DYNAMIC_FTRACE */
+static void
+ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip)
+{
+ struct ftrace_ops *op;
+
+ /*
+ * Some of the ops may be dynamically allocated,
+ * they must be freed after a synchronize_sched().
+ */
+ preempt_disable_notrace();
+ op = rcu_dereference_raw(ftrace_ops_list);
+ while (op != &ftrace_list_end) {
+ if (ftrace_ops_test(op, ip))
+ op->func(ip, parent_ip);
+ op = rcu_dereference_raw(op->next);
+ };
+ preempt_enable_notrace();
+}
+
static void clear_ftrace_swapper(void)
{
struct task_struct *p;
@@ -3143,19 +3790,23 @@ void ftrace_kill(void)
*/
int register_ftrace_function(struct ftrace_ops *ops)
{
- int ret;
-
- if (unlikely(ftrace_disabled))
- return -1;
+ int ret = -1;
mutex_lock(&ftrace_lock);
+ if (unlikely(ftrace_disabled))
+ goto out_unlock;
+
ret = __register_ftrace_function(ops);
- ftrace_startup(0);
+ if (!ret)
+ ftrace_startup(ops, 0);
+
+ out_unlock:
mutex_unlock(&ftrace_lock);
return ret;
}
+EXPORT_SYMBOL_GPL(register_ftrace_function);
/**
* unregister_ftrace_function - unregister a function for profiling.
@@ -3169,25 +3820,27 @@ int unregister_ftrace_function(struct ftrace_ops *ops)
mutex_lock(&ftrace_lock);
ret = __unregister_ftrace_function(ops);
- ftrace_shutdown(0);
+ if (!ret)
+ ftrace_shutdown(ops, 0);
mutex_unlock(&ftrace_lock);
return ret;
}
+EXPORT_SYMBOL_GPL(unregister_ftrace_function);
int
ftrace_enable_sysctl(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp,
loff_t *ppos)
{
- int ret;
-
- if (unlikely(ftrace_disabled))
- return -ENODEV;
+ int ret = -ENODEV;
mutex_lock(&ftrace_lock);
- ret = proc_dointvec(table, write, buffer, lenp, ppos);
+ if (unlikely(ftrace_disabled))
+ goto out;
+
+ ret = proc_dointvec(table, write, buffer, lenp, ppos);
if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled))
goto out;
@@ -3199,11 +3852,11 @@ ftrace_enable_sysctl(struct ctl_table *table, int write,
ftrace_startup_sysctl();
/* we are starting ftrace again */
- if (ftrace_list != &ftrace_list_end) {
- if (ftrace_list->next == &ftrace_list_end)
- ftrace_trace_function = ftrace_list->func;
+ if (ftrace_ops_list != &ftrace_list_end) {
+ if (ftrace_ops_list->next == &ftrace_list_end)
+ ftrace_trace_function = ftrace_ops_list->func;
else
- ftrace_trace_function = ftrace_list_func;
+ ftrace_trace_function = ftrace_ops_list_func;
}
} else {
@@ -3392,7 +4045,7 @@ int register_ftrace_graph(trace_func_graph_ret_t retfunc,
ftrace_graph_return = retfunc;
ftrace_graph_entry = entryfunc;
- ftrace_startup(FTRACE_START_FUNC_RET);
+ ftrace_startup(&global_ops, FTRACE_START_FUNC_RET);
out:
mutex_unlock(&ftrace_lock);
@@ -3409,7 +4062,7 @@ void unregister_ftrace_graph(void)
ftrace_graph_active--;
ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub;
ftrace_graph_entry = ftrace_graph_entry_stub;
- ftrace_shutdown(FTRACE_STOP_FUNC_RET);
+ ftrace_shutdown(&global_ops, FTRACE_STOP_FUNC_RET);
unregister_pm_notifier(&ftrace_suspend_notifier);
unregister_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL);
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index d38c16a06a6..ee9c921d7f2 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1110,6 +1110,7 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags,
entry->preempt_count = pc & 0xff;
entry->pid = (tsk) ? tsk->pid : 0;
+ entry->padding = 0;
entry->flags =
#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
(irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) |
@@ -2013,9 +2014,10 @@ enum print_line_t print_trace_line(struct trace_iterator *iter)
{
enum print_line_t ret;
- if (iter->lost_events)
- trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n",
- iter->cpu, iter->lost_events);
+ if (iter->lost_events &&
+ !trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n",
+ iter->cpu, iter->lost_events))
+ return TRACE_TYPE_PARTIAL_LINE;
if (iter->trace && iter->trace->print_line) {
ret = iter->trace->print_line(iter);
@@ -3229,6 +3231,14 @@ waitagain:
if (iter->seq.len >= cnt)
break;
+
+ /*
+ * Setting the full flag means we reached the trace_seq buffer
+ * size and we should leave by partial output condition above.
+ * One of the trace_seq_* functions is not used properly.
+ */
+ WARN_ONCE(iter->seq.full, "full flag set for trace type %d",
+ iter->ent->type);
}
trace_access_unlock(iter->cpu_file);
trace_event_read_unlock();
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 5e9dfc6286d..6b69c4bd306 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -419,6 +419,8 @@ extern void trace_find_cmdline(int pid, char comm[]);
extern unsigned long ftrace_update_tot_cnt;
#define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
extern int DYN_FTRACE_TEST_NAME(void);
+#define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
+extern int DYN_FTRACE_TEST_NAME2(void);
#endif
extern int ring_buffer_expanded;
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index e88f74fe1d4..2fe11034135 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -116,6 +116,7 @@ static int trace_define_common_fields(void)
__common_field(unsigned char, flags);
__common_field(unsigned char, preempt_count);
__common_field(int, pid);
+ __common_field(int, padding);
return ret;
}
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index 16aee4d44e8..8d0e1cc4e97 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -149,11 +149,13 @@ function_stack_trace_call(unsigned long ip, unsigned long parent_ip)
static struct ftrace_ops trace_ops __read_mostly =
{
.func = function_trace_call,
+ .flags = FTRACE_OPS_FL_GLOBAL,
};
static struct ftrace_ops trace_stack_ops __read_mostly =
{
.func = function_stack_trace_call,
+ .flags = FTRACE_OPS_FL_GLOBAL,
};
/* Our two options */
diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c
index a4969b47afc..c77424be284 100644
--- a/kernel/trace/trace_irqsoff.c
+++ b/kernel/trace/trace_irqsoff.c
@@ -153,6 +153,7 @@ irqsoff_tracer_call(unsigned long ip, unsigned long parent_ip)
static struct ftrace_ops trace_ops __read_mostly =
{
.func = irqsoff_tracer_call,
+ .flags = FTRACE_OPS_FL_GLOBAL,
};
#endif /* CONFIG_FUNCTION_TRACER */
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 35d55a38614..f925c45f0af 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -53,7 +53,6 @@ const char *reserved_field_names[] = {
"common_preempt_count",
"common_pid",
"common_tgid",
- "common_lock_depth",
FIELD_STRING_IP,
FIELD_STRING_RETIP,
FIELD_STRING_FUNC,
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index 456be9063c2..cf535ccedc8 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -830,6 +830,9 @@ EXPORT_SYMBOL_GPL(unregister_ftrace_event);
enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags,
struct trace_event *event)
{
+ if (!trace_seq_printf(&iter->seq, "type: %d\n", iter->ent->type))
+ return TRACE_TYPE_PARTIAL_LINE;
+
return TRACE_TYPE_HANDLED;
}
diff --git a/kernel/trace/trace_printk.c b/kernel/trace/trace_printk.c
index 2547d8813cf..dff763b7baf 100644
--- a/kernel/trace/trace_printk.c
+++ b/kernel/trace/trace_printk.c
@@ -32,7 +32,7 @@ static DEFINE_MUTEX(btrace_mutex);
struct trace_bprintk_fmt {
struct list_head list;
- char fmt[0];
+ const char *fmt;
};
static inline struct trace_bprintk_fmt *lookup_format(const char *fmt)
@@ -49,6 +49,7 @@ static
void hold_module_trace_bprintk_format(const char **start, const char **end)
{
const char **iter;
+ char *fmt;
mutex_lock(&btrace_mutex);
for (iter = start; iter < end; iter++) {
@@ -58,14 +59,18 @@ void hold_module_trace_bprintk_format(const char **start, const char **end)
continue;
}
- tb_fmt = kmalloc(offsetof(struct trace_bprintk_fmt, fmt)
- + strlen(*iter) + 1, GFP_KERNEL);
- if (tb_fmt) {
+ tb_fmt = kmalloc(sizeof(*tb_fmt), GFP_KERNEL);
+ if (tb_fmt)
+ fmt = kmalloc(strlen(*iter) + 1, GFP_KERNEL);
+ if (tb_fmt && fmt) {
list_add_tail(&tb_fmt->list, &trace_bprintk_fmt_list);
- strcpy(tb_fmt->fmt, *iter);
+ strcpy(fmt, *iter);
+ tb_fmt->fmt = fmt;
*iter = tb_fmt->fmt;
- } else
+ } else {
+ kfree(tb_fmt);
*iter = NULL;
+ }
}
mutex_unlock(&btrace_mutex);
}
@@ -84,6 +89,76 @@ static int module_trace_bprintk_format_notify(struct notifier_block *self,
return 0;
}
+/*
+ * The debugfs/tracing/printk_formats file maps the addresses with
+ * the ASCII formats that are used in the bprintk events in the
+ * buffer. For userspace tools to be able to decode the events from
+ * the buffer, they need to be able to map the address with the format.
+ *
+ * The addresses of the bprintk formats are in their own section
+ * __trace_printk_fmt. But for modules we copy them into a link list.
+ * The code to print the formats and their addresses passes around the
+ * address of the fmt string. If the fmt address passed into the seq
+ * functions is within the kernel core __trace_printk_fmt section, then
+ * it simply uses the next pointer in the list.
+ *
+ * When the fmt pointer is outside the kernel core __trace_printk_fmt
+ * section, then we need to read the link list pointers. The trick is
+ * we pass the address of the string to the seq function just like
+ * we do for the kernel core formats. To get back the structure that
+ * holds the format, we simply use containerof() and then go to the
+ * next format in the list.
+ */
+static const char **
+find_next_mod_format(int start_index, void *v, const char **fmt, loff_t *pos)
+{
+ struct trace_bprintk_fmt *mod_fmt;
+
+ if (list_empty(&trace_bprintk_fmt_list))
+ return NULL;
+
+ /*
+ * v will point to the address of the fmt record from t_next
+ * v will be NULL from t_start.
+ * If this is the first pointer or called from start
+ * then we need to walk the list.
+ */
+ if (!v || start_index == *pos) {
+ struct trace_bprintk_fmt *p;
+
+ /* search the module list */
+ list_for_each_entry(p, &trace_bprintk_fmt_list, list) {
+ if (start_index == *pos)
+ return &p->fmt;
+ start_index++;
+ }
+ /* pos > index */
+ return NULL;
+ }
+
+ /*
+ * v points to the address of the fmt field in the mod list
+ * structure that holds the module print format.
+ */
+ mod_fmt = container_of(v, typeof(*mod_fmt), fmt);
+ if (mod_fmt->list.next == &trace_bprintk_fmt_list)
+ return NULL;
+
+ mod_fmt = container_of(mod_fmt->list.next, typeof(*mod_fmt), list);
+
+ return &mod_fmt->fmt;
+}
+
+static void format_mod_start(void)
+{
+ mutex_lock(&btrace_mutex);
+}
+
+static void format_mod_stop(void)
+{
+ mutex_unlock(&btrace_mutex);
+}
+
#else /* !CONFIG_MODULES */
__init static int
module_trace_bprintk_format_notify(struct notifier_block *self,
@@ -91,6 +166,13 @@ module_trace_bprintk_format_notify(struct notifier_block *self,
{
return 0;
}
+static inline const char **
+find_next_mod_format(int start_index, void *v, const char **fmt, loff_t *pos)
+{
+ return NULL;
+}
+static inline void format_mod_start(void) { }
+static inline void format_mod_stop(void) { }
#endif /* CONFIG_MODULES */
@@ -153,20 +235,33 @@ int __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap)
}
EXPORT_SYMBOL_GPL(__ftrace_vprintk);
+static const char **find_next(void *v, loff_t *pos)
+{
+ const char **fmt = v;
+ int start_index;
+
+ if (!fmt)
+ fmt = __start___trace_bprintk_fmt + *pos;
+
+ start_index = __stop___trace_bprintk_fmt - __start___trace_bprintk_fmt;
+
+ if (*pos < start_index)
+ return fmt;
+
+ return find_next_mod_format(start_index, v, fmt, pos);
+}
+
static void *
t_start(struct seq_file *m, loff_t *pos)
{
- const char **fmt = __start___trace_bprintk_fmt + *pos;
-
- if ((unsigned long)fmt >= (unsigned long)__stop___trace_bprintk_fmt)
- return NULL;
- return fmt;
+ format_mod_start();
+ return find_next(NULL, pos);
}
static void *t_next(struct seq_file *m, void * v, loff_t *pos)
{
(*pos)++;
- return t_start(m, pos);
+ return find_next(v, pos);
}
static int t_show(struct seq_file *m, void *v)
@@ -205,6 +300,7 @@ static int t_show(struct seq_file *m, void *v)
static void t_stop(struct seq_file *m, void *p)
{
+ format_mod_stop();
}
static const struct seq_operations show_format_seq_ops = {
diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c
index 7319559ed59..f029dd4fd2c 100644
--- a/kernel/trace/trace_sched_wakeup.c
+++ b/kernel/trace/trace_sched_wakeup.c
@@ -129,6 +129,7 @@ wakeup_tracer_call(unsigned long ip, unsigned long parent_ip)
static struct ftrace_ops trace_ops __read_mostly =
{
.func = wakeup_tracer_call,
+ .flags = FTRACE_OPS_FL_GLOBAL,
};
#endif /* CONFIG_FUNCTION_TRACER */
diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index 659732eba07..288541f977f 100644
--- a/kernel/trace/trace_selftest.c
+++ b/kernel/trace/trace_selftest.c
@@ -101,6 +101,206 @@ static inline void warn_failed_init_tracer(struct tracer *trace, int init_ret)
#ifdef CONFIG_DYNAMIC_FTRACE
+static int trace_selftest_test_probe1_cnt;
+static void trace_selftest_test_probe1_func(unsigned long ip,
+ unsigned long pip)
+{
+ trace_selftest_test_probe1_cnt++;
+}
+
+static int trace_selftest_test_probe2_cnt;
+static void trace_selftest_test_probe2_func(unsigned long ip,
+ unsigned long pip)
+{
+ trace_selftest_test_probe2_cnt++;
+}
+
+static int trace_selftest_test_probe3_cnt;
+static void trace_selftest_test_probe3_func(unsigned long ip,
+ unsigned long pip)
+{
+ trace_selftest_test_probe3_cnt++;
+}
+
+static int trace_selftest_test_global_cnt;
+static void trace_selftest_test_global_func(unsigned long ip,
+ unsigned long pip)
+{
+ trace_selftest_test_global_cnt++;
+}
+
+static int trace_selftest_test_dyn_cnt;
+static void trace_selftest_test_dyn_func(unsigned long ip,
+ unsigned long pip)
+{
+ trace_selftest_test_dyn_cnt++;
+}
+
+static struct ftrace_ops test_probe1 = {
+ .func = trace_selftest_test_probe1_func,
+};
+
+static struct ftrace_ops test_probe2 = {
+ .func = trace_selftest_test_probe2_func,
+};
+
+static struct ftrace_ops test_probe3 = {
+ .func = trace_selftest_test_probe3_func,
+};
+
+static struct ftrace_ops test_global = {
+ .func = trace_selftest_test_global_func,
+ .flags = FTRACE_OPS_FL_GLOBAL,
+};
+
+static void print_counts(void)
+{
+ printk("(%d %d %d %d %d) ",
+ trace_selftest_test_probe1_cnt,
+ trace_selftest_test_probe2_cnt,
+ trace_selftest_test_probe3_cnt,
+ trace_selftest_test_global_cnt,
+ trace_selftest_test_dyn_cnt);
+}
+
+static void reset_counts(void)
+{
+ trace_selftest_test_probe1_cnt = 0;
+ trace_selftest_test_probe2_cnt = 0;
+ trace_selftest_test_probe3_cnt = 0;
+ trace_selftest_test_global_cnt = 0;
+ trace_selftest_test_dyn_cnt = 0;
+}
+
+static int trace_selftest_ops(int cnt)
+{
+ int save_ftrace_enabled = ftrace_enabled;
+ struct ftrace_ops *dyn_ops;
+ char *func1_name;
+ char *func2_name;
+ int len1;
+ int len2;
+ int ret = -1;
+
+ printk(KERN_CONT "PASSED\n");
+ pr_info("Testing dynamic ftrace ops #%d: ", cnt);
+
+ ftrace_enabled = 1;
+ reset_counts();
+
+ /* Handle PPC64 '.' name */
+ func1_name = "*" __stringify(DYN_FTRACE_TEST_NAME);
+ func2_name = "*" __stringify(DYN_FTRACE_TEST_NAME2);
+ len1 = strlen(func1_name);
+ len2 = strlen(func2_name);
+
+ /*
+ * Probe 1 will trace function 1.
+ * Probe 2 will trace function 2.
+ * Probe 3 will trace functions 1 and 2.
+ */
+ ftrace_set_filter(&test_probe1, func1_name, len1, 1);
+ ftrace_set_filter(&test_probe2, func2_name, len2, 1);
+ ftrace_set_filter(&test_probe3, func1_name, len1, 1);
+ ftrace_set_filter(&test_probe3, func2_name, len2, 0);
+
+ register_ftrace_function(&test_probe1);
+ register_ftrace_function(&test_probe2);
+ register_ftrace_function(&test_probe3);
+ register_ftrace_function(&test_global);
+
+ DYN_FTRACE_TEST_NAME();
+
+ print_counts();
+
+ if (trace_selftest_test_probe1_cnt != 1)
+ goto out;
+ if (trace_selftest_test_probe2_cnt != 0)
+ goto out;
+ if (trace_selftest_test_probe3_cnt != 1)
+ goto out;
+ if (trace_selftest_test_global_cnt == 0)
+ goto out;
+
+ DYN_FTRACE_TEST_NAME2();
+
+ print_counts();
+
+ if (trace_selftest_test_probe1_cnt != 1)
+ goto out;
+ if (trace_selftest_test_probe2_cnt != 1)
+ goto out;
+ if (trace_selftest_test_probe3_cnt != 2)
+ goto out;
+
+ /* Add a dynamic probe */
+ dyn_ops = kzalloc(sizeof(*dyn_ops), GFP_KERNEL);
+ if (!dyn_ops) {
+ printk("MEMORY ERROR ");
+ goto out;
+ }
+
+ dyn_ops->func = trace_selftest_test_dyn_func;
+
+ register_ftrace_function(dyn_ops);
+
+ trace_selftest_test_global_cnt = 0;
+
+ DYN_FTRACE_TEST_NAME();
+
+ print_counts();
+
+ if (trace_selftest_test_probe1_cnt != 2)
+ goto out_free;
+ if (trace_selftest_test_probe2_cnt != 1)
+ goto out_free;
+ if (trace_selftest_test_probe3_cnt != 3)
+ goto out_free;
+ if (trace_selftest_test_global_cnt == 0)
+ goto out;
+ if (trace_selftest_test_dyn_cnt == 0)
+ goto out_free;
+
+ DYN_FTRACE_TEST_NAME2();
+
+ print_counts();
+
+ if (trace_selftest_test_probe1_cnt != 2)
+ goto out_free;
+ if (trace_selftest_test_probe2_cnt != 2)
+ goto out_free;
+ if (trace_selftest_test_probe3_cnt != 4)
+ goto out_free;
+
+ ret = 0;
+ out_free:
+ unregister_ftrace_function(dyn_ops);
+ kfree(dyn_ops);
+
+ out:
+ /* Purposely unregister in the same order */
+ unregister_ftrace_function(&test_probe1);
+ unregister_ftrace_function(&test_probe2);
+ unregister_ftrace_function(&test_probe3);
+ unregister_ftrace_function(&test_global);
+
+ /* Make sure everything is off */
+ reset_counts();
+ DYN_FTRACE_TEST_NAME();
+ DYN_FTRACE_TEST_NAME();
+
+ if (trace_selftest_test_probe1_cnt ||
+ trace_selftest_test_probe2_cnt ||
+ trace_selftest_test_probe3_cnt ||
+ trace_selftest_test_global_cnt ||
+ trace_selftest_test_dyn_cnt)
+ ret = -1;
+
+ ftrace_enabled = save_ftrace_enabled;
+
+ return ret;
+}
+
/* Test dynamic code modification and ftrace filters */
int trace_selftest_startup_dynamic_tracing(struct tracer *trace,
struct trace_array *tr,
@@ -131,7 +331,7 @@ int trace_selftest_startup_dynamic_tracing(struct tracer *trace,
func_name = "*" __stringify(DYN_FTRACE_TEST_NAME);
/* filter only on our function */
- ftrace_set_filter(func_name, strlen(func_name), 1);
+ ftrace_set_global_filter(func_name, strlen(func_name), 1);
/* enable tracing */
ret = tracer_init(trace, tr);
@@ -166,22 +366,30 @@ int trace_selftest_startup_dynamic_tracing(struct tracer *trace,
/* check the trace buffer */
ret = trace_test_buffer(tr, &count);
- trace->reset(tr);
tracing_start();
/* we should only have one item */
if (!ret && count != 1) {
+ trace->reset(tr);
printk(KERN_CONT ".. filter failed count=%ld ..", count);
ret = -1;
goto out;
}
+ /* Test the ops with global tracing running */
+ ret = trace_selftest_ops(1);
+ trace->reset(tr);
+
out:
ftrace_enabled = save_ftrace_enabled;
tracer_enabled = save_tracer_enabled;
/* Enable tracing on all functions again */
- ftrace_set_filter(NULL, 0, 1);
+ ftrace_set_global_filter(NULL, 0, 1);
+
+ /* Test the ops with global tracing off */
+ if (!ret)
+ ret = trace_selftest_ops(2);
return ret;
}
diff --git a/kernel/trace/trace_selftest_dynamic.c b/kernel/trace/trace_selftest_dynamic.c
index 54dd77cce5b..b4c475a0a48 100644
--- a/kernel/trace/trace_selftest_dynamic.c
+++ b/kernel/trace/trace_selftest_dynamic.c
@@ -5,3 +5,9 @@ int DYN_FTRACE_TEST_NAME(void)
/* used to call mcount */
return 0;
}
+
+int DYN_FTRACE_TEST_NAME2(void)
+{
+ /* used to call mcount */
+ return 0;
+}
diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c
index 4c5dead0c23..b0b53b8e4c2 100644
--- a/kernel/trace/trace_stack.c
+++ b/kernel/trace/trace_stack.c
@@ -133,6 +133,7 @@ stack_trace_call(unsigned long ip, unsigned long parent_ip)
static struct ftrace_ops trace_ops __read_mostly =
{
.func = stack_trace_call,
+ .flags = FTRACE_OPS_FL_GLOBAL,
};
static ssize_t
diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c
index 68187af4889..b219f1449c5 100644
--- a/kernel/tracepoint.c
+++ b/kernel/tracepoint.c
@@ -251,9 +251,9 @@ static void set_tracepoint(struct tracepoint_entry **entry,
{
WARN_ON(strcmp((*entry)->name, elem->name) != 0);
- if (elem->regfunc && !elem->state && active)
+ if (elem->regfunc && !jump_label_enabled(&elem->key) && active)
elem->regfunc();
- else if (elem->unregfunc && elem->state && !active)
+ else if (elem->unregfunc && jump_label_enabled(&elem->key) && !active)
elem->unregfunc();
/*
@@ -264,13 +264,10 @@ static void set_tracepoint(struct tracepoint_entry **entry,
* is used.
*/
rcu_assign_pointer(elem->funcs, (*entry)->funcs);
- if (!elem->state && active) {
- jump_label_enable(&elem->state);
- elem->state = active;
- } else if (elem->state && !active) {
- jump_label_disable(&elem->state);
- elem->state = active;
- }
+ if (active && !jump_label_enabled(&elem->key))
+ jump_label_inc(&elem->key);
+ else if (!active && jump_label_enabled(&elem->key))
+ jump_label_dec(&elem->key);
}
/*
@@ -281,13 +278,11 @@ static void set_tracepoint(struct tracepoint_entry **entry,
*/
static void disable_tracepoint(struct tracepoint *elem)
{
- if (elem->unregfunc && elem->state)
+ if (elem->unregfunc && jump_label_enabled(&elem->key))
elem->unregfunc();
- if (elem->state) {
- jump_label_disable(&elem->state);
- elem->state = 0;
- }
+ if (jump_label_enabled(&elem->key))
+ jump_label_dec(&elem->key);
rcu_assign_pointer(elem->funcs, NULL);
}