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-rw-r--r--Documentation/kernel-parameters.txt2
-rw-r--r--arch/Kconfig3
-rw-r--r--arch/s390/Kconfig1
-rw-r--r--arch/s390/include/asm/mutex.h2
-rw-r--r--fs/proc/base.c79
-rw-r--r--include/linux/completion.h8
-rw-r--r--include/linux/init_task.h9
-rw-r--r--include/linux/mutex.h4
-rw-r--r--include/linux/sched.h36
-rw-r--r--init/Kconfig13
-rw-r--r--kernel/cpu.c18
-rw-r--r--kernel/fork.c7
-rw-r--r--kernel/irq/manage.c4
-rw-r--r--kernel/kthread.c2
-rw-r--r--kernel/mutex.c2
-rw-r--r--kernel/printk.c8
-rw-r--r--kernel/sched.c569
-rw-r--r--kernel/sched_autogroup.c238
-rw-r--r--kernel/sched_autogroup.h32
-rw-r--r--kernel/sched_clock.c2
-rw-r--r--kernel/sched_debug.c91
-rw-r--r--kernel/sched_fair.c322
-rw-r--r--kernel/sched_features.h2
-rw-r--r--kernel/sched_rt.c24
-rw-r--r--kernel/softirq.c4
-rw-r--r--kernel/sys.c4
-rw-r--r--kernel/sysctl.c37
-rw-r--r--kernel/trace/trace_selftest.c2
-rw-r--r--kernel/watchdog.c2
29 files changed, 930 insertions, 597 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 992cda68fa6..d6496fde618 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1614,6 +1614,8 @@ and is between 256 and 4096 characters. It is defined in the file
noapic [SMP,APIC] Tells the kernel to not make use of any
IOAPICs that may be present in the system.
+ noautogroup Disable scheduler automatic task group creation.
+
nobats [PPC] Do not use BATs for mapping kernel lowmem
on "Classic" PPC cores.
diff --git a/arch/Kconfig b/arch/Kconfig
index 8bf0fa652eb..f78c2be4242 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -175,4 +175,7 @@ config HAVE_PERF_EVENTS_NMI
config HAVE_ARCH_JUMP_LABEL
bool
+config HAVE_ARCH_MUTEX_CPU_RELAX
+ bool
+
source "kernel/gcov/Kconfig"
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index e0b98e71ff4..6c6d7b339aa 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -99,6 +99,7 @@ config S390
select HAVE_KERNEL_LZMA
select HAVE_KERNEL_LZO
select HAVE_GET_USER_PAGES_FAST
+ select HAVE_ARCH_MUTEX_CPU_RELAX
select ARCH_INLINE_SPIN_TRYLOCK
select ARCH_INLINE_SPIN_TRYLOCK_BH
select ARCH_INLINE_SPIN_LOCK
diff --git a/arch/s390/include/asm/mutex.h b/arch/s390/include/asm/mutex.h
index 458c1f7fbc1..688271f5f2e 100644
--- a/arch/s390/include/asm/mutex.h
+++ b/arch/s390/include/asm/mutex.h
@@ -7,3 +7,5 @@
*/
#include <asm-generic/mutex-dec.h>
+
+#define arch_mutex_cpu_relax() barrier()
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 182845147fe..08cba2c3b61 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -1407,6 +1407,82 @@ static const struct file_operations proc_pid_sched_operations = {
#endif
+#ifdef CONFIG_SCHED_AUTOGROUP
+/*
+ * Print out autogroup related information:
+ */
+static int sched_autogroup_show(struct seq_file *m, void *v)
+{
+ struct inode *inode = m->private;
+ struct task_struct *p;
+
+ p = get_proc_task(inode);
+ if (!p)
+ return -ESRCH;
+ proc_sched_autogroup_show_task(p, m);
+
+ put_task_struct(p);
+
+ return 0;
+}
+
+static ssize_t
+sched_autogroup_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *offset)
+{
+ struct inode *inode = file->f_path.dentry->d_inode;
+ struct task_struct *p;
+ char buffer[PROC_NUMBUF];
+ long nice;
+ int err;
+
+ memset(buffer, 0, sizeof(buffer));
+ if (count > sizeof(buffer) - 1)
+ count = sizeof(buffer) - 1;
+ if (copy_from_user(buffer, buf, count))
+ return -EFAULT;
+
+ err = strict_strtol(strstrip(buffer), 0, &nice);
+ if (err)
+ return -EINVAL;
+
+ p = get_proc_task(inode);
+ if (!p)
+ return -ESRCH;
+
+ err = nice;
+ err = proc_sched_autogroup_set_nice(p, &err);
+ if (err)
+ count = err;
+
+ put_task_struct(p);
+
+ return count;
+}
+
+static int sched_autogroup_open(struct inode *inode, struct file *filp)
+{
+ int ret;
+
+ ret = single_open(filp, sched_autogroup_show, NULL);
+ if (!ret) {
+ struct seq_file *m = filp->private_data;
+
+ m->private = inode;
+ }
+ return ret;
+}
+
+static const struct file_operations proc_pid_sched_autogroup_operations = {
+ .open = sched_autogroup_open,
+ .read = seq_read,
+ .write = sched_autogroup_write,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+#endif /* CONFIG_SCHED_AUTOGROUP */
+
static ssize_t comm_write(struct file *file, const char __user *buf,
size_t count, loff_t *offset)
{
@@ -2733,6 +2809,9 @@ static const struct pid_entry tgid_base_stuff[] = {
#ifdef CONFIG_SCHED_DEBUG
REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
#endif
+#ifdef CONFIG_SCHED_AUTOGROUP
+ REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations),
+#endif
REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
INF("syscall", S_IRUSR, proc_pid_syscall),
diff --git a/include/linux/completion.h b/include/linux/completion.h
index 36d57f74cd0..51494e6b554 100644
--- a/include/linux/completion.h
+++ b/include/linux/completion.h
@@ -81,10 +81,10 @@ extern int wait_for_completion_interruptible(struct completion *x);
extern int wait_for_completion_killable(struct completion *x);
extern unsigned long wait_for_completion_timeout(struct completion *x,
unsigned long timeout);
-extern unsigned long wait_for_completion_interruptible_timeout(
- struct completion *x, unsigned long timeout);
-extern unsigned long wait_for_completion_killable_timeout(
- struct completion *x, unsigned long timeout);
+extern long wait_for_completion_interruptible_timeout(
+ struct completion *x, unsigned long timeout);
+extern long wait_for_completion_killable_timeout(
+ struct completion *x, unsigned long timeout);
extern bool try_wait_for_completion(struct completion *x);
extern bool completion_done(struct completion *x);
diff --git a/include/linux/init_task.h b/include/linux/init_task.h
index 6b281fae114..caa151fbebb 100644
--- a/include/linux/init_task.h
+++ b/include/linux/init_task.h
@@ -12,6 +12,13 @@
#include <linux/securebits.h>
#include <net/net_namespace.h>
+#ifdef CONFIG_SMP
+# define INIT_PUSHABLE_TASKS(tsk) \
+ .pushable_tasks = PLIST_NODE_INIT(tsk.pushable_tasks, MAX_PRIO),
+#else
+# define INIT_PUSHABLE_TASKS(tsk)
+#endif
+
extern struct files_struct init_files;
extern struct fs_struct init_fs;
@@ -144,7 +151,7 @@ extern struct cred init_cred;
.nr_cpus_allowed = NR_CPUS, \
}, \
.tasks = LIST_HEAD_INIT(tsk.tasks), \
- .pushable_tasks = PLIST_NODE_INIT(tsk.pushable_tasks, MAX_PRIO), \
+ INIT_PUSHABLE_TASKS(tsk) \
.ptraced = LIST_HEAD_INIT(tsk.ptraced), \
.ptrace_entry = LIST_HEAD_INIT(tsk.ptrace_entry), \
.real_parent = &tsk, \
diff --git a/include/linux/mutex.h b/include/linux/mutex.h
index f363bc8fdc7..94b48bd40dd 100644
--- a/include/linux/mutex.h
+++ b/include/linux/mutex.h
@@ -160,4 +160,8 @@ extern int mutex_trylock(struct mutex *lock);
extern void mutex_unlock(struct mutex *lock);
extern int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock);
+#ifndef CONFIG_HAVE_ARCH_MUTEX_CPU_RELAX
+#define arch_mutex_cpu_relax() cpu_relax()
+#endif
+
#endif
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 48c409c279d..777cd01e240 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -513,6 +513,8 @@ struct thread_group_cputimer {
spinlock_t lock;
};
+struct autogroup;
+
/*
* NOTE! "signal_struct" does not have it's own
* locking, because a shared signal_struct always
@@ -580,6 +582,9 @@ struct signal_struct {
struct tty_struct *tty; /* NULL if no tty */
+#ifdef CONFIG_SCHED_AUTOGROUP
+ struct autogroup *autogroup;
+#endif
/*
* Cumulative resource counters for dead threads in the group,
* and for reaped dead child processes forked by this group.
@@ -1242,7 +1247,9 @@ struct task_struct {
#endif
struct list_head tasks;
+#ifdef CONFIG_SMP
struct plist_node pushable_tasks;
+#endif
struct mm_struct *mm, *active_mm;
#if defined(SPLIT_RSS_COUNTING)
@@ -1883,14 +1890,11 @@ extern void sched_clock_idle_sleep_event(void);
extern void sched_clock_idle_wakeup_event(u64 delta_ns);
#ifdef CONFIG_HOTPLUG_CPU
-extern void move_task_off_dead_cpu(int dead_cpu, struct task_struct *p);
extern void idle_task_exit(void);
#else
static inline void idle_task_exit(void) {}
#endif
-extern void sched_idle_next(void);
-
#if defined(CONFIG_NO_HZ) && defined(CONFIG_SMP)
extern void wake_up_idle_cpu(int cpu);
#else
@@ -1900,8 +1904,6 @@ static inline void wake_up_idle_cpu(int cpu) { }
extern unsigned int sysctl_sched_latency;
extern unsigned int sysctl_sched_min_granularity;
extern unsigned int sysctl_sched_wakeup_granularity;
-extern unsigned int sysctl_sched_shares_ratelimit;
-extern unsigned int sysctl_sched_shares_thresh;
extern unsigned int sysctl_sched_child_runs_first;
enum sched_tunable_scaling {
@@ -1917,6 +1919,7 @@ extern unsigned int sysctl_sched_migration_cost;
extern unsigned int sysctl_sched_nr_migrate;
extern unsigned int sysctl_sched_time_avg;
extern unsigned int sysctl_timer_migration;
+extern unsigned int sysctl_sched_shares_window;
int sched_proc_update_handler(struct ctl_table *table, int write,
void __user *buffer, size_t *length,
@@ -1942,6 +1945,24 @@ int sched_rt_handler(struct ctl_table *table, int write,
extern unsigned int sysctl_sched_compat_yield;
+#ifdef CONFIG_SCHED_AUTOGROUP
+extern unsigned int sysctl_sched_autogroup_enabled;
+
+extern void sched_autogroup_create_attach(struct task_struct *p);
+extern void sched_autogroup_detach(struct task_struct *p);
+extern void sched_autogroup_fork(struct signal_struct *sig);
+extern void sched_autogroup_exit(struct signal_struct *sig);
+#ifdef CONFIG_PROC_FS
+extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m);
+extern int proc_sched_autogroup_set_nice(struct task_struct *p, int *nice);
+#endif
+#else
+static inline void sched_autogroup_create_attach(struct task_struct *p) { }
+static inline void sched_autogroup_detach(struct task_struct *p) { }
+static inline void sched_autogroup_fork(struct signal_struct *sig) { }
+static inline void sched_autogroup_exit(struct signal_struct *sig) { }
+#endif
+
#ifdef CONFIG_RT_MUTEXES
extern int rt_mutex_getprio(struct task_struct *p);
extern void rt_mutex_setprio(struct task_struct *p, int prio);
@@ -1960,9 +1981,10 @@ extern int task_nice(const struct task_struct *p);
extern int can_nice(const struct task_struct *p, const int nice);
extern int task_curr(const struct task_struct *p);
extern int idle_cpu(int cpu);
-extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
+extern int sched_setscheduler(struct task_struct *, int,
+ const struct sched_param *);
extern int sched_setscheduler_nocheck(struct task_struct *, int,
- struct sched_param *);
+ const struct sched_param *);
extern struct task_struct *idle_task(int cpu);
extern struct task_struct *curr_task(int cpu);
extern void set_curr_task(int cpu, struct task_struct *p);
diff --git a/init/Kconfig b/init/Kconfig
index 526ec1c7456..8dfd094e687 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -794,6 +794,19 @@ config NET_NS
endif # NAMESPACES
+config SCHED_AUTOGROUP
+ bool "Automatic process group scheduling"
+ select EVENTFD
+ select CGROUPS
+ select CGROUP_SCHED
+ select FAIR_GROUP_SCHED
+ help
+ This option optimizes the scheduler for common desktop workloads by
+ automatically creating and populating task groups. This separation
+ of workloads isolates aggressive CPU burners (like build jobs) from
+ desktop applications. Task group autogeneration is currently based
+ upon task session.
+
config MM_OWNER
bool
diff --git a/kernel/cpu.c b/kernel/cpu.c
index f6e726f1849..cb7a1efa9c2 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -189,7 +189,6 @@ static inline void check_for_tasks(int cpu)
}
struct take_cpu_down_param {
- struct task_struct *caller;
unsigned long mod;
void *hcpu;
};
@@ -198,7 +197,6 @@ struct take_cpu_down_param {
static int __ref take_cpu_down(void *_param)
{
struct take_cpu_down_param *param = _param;
- unsigned int cpu = (unsigned long)param->hcpu;
int err;
/* Ensure this CPU doesn't handle any more interrupts. */
@@ -208,11 +206,6 @@ static int __ref take_cpu_down(void *_param)
cpu_notify(CPU_DYING | param->mod, param->hcpu);
- if (task_cpu(param->caller) == cpu)
- move_task_off_dead_cpu(cpu, param->caller);
- /* Force idle task to run as soon as we yield: it should
- immediately notice cpu is offline and die quickly. */
- sched_idle_next();
return 0;
}
@@ -223,7 +216,6 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
void *hcpu = (void *)(long)cpu;
unsigned long mod = tasks_frozen ? CPU_TASKS_FROZEN : 0;
struct take_cpu_down_param tcd_param = {
- .caller = current,
.mod = mod,
.hcpu = hcpu,
};
@@ -253,9 +245,15 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
}
BUG_ON(cpu_online(cpu));
- /* Wait for it to sleep (leaving idle task). */
+ /*
+ * The migration_call() CPU_DYING callback will have removed all
+ * runnable tasks from the cpu, there's only the idle task left now
+ * that the migration thread is done doing the stop_machine thing.
+ *
+ * Wait for the stop thread to go away.
+ */
while (!idle_cpu(cpu))
- yield();
+ cpu_relax();
/* This actually kills the CPU. */
__cpu_die(cpu);
diff --git a/kernel/fork.c b/kernel/fork.c
index 5447dc7defa..7d164e25b0f 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -174,8 +174,10 @@ static inline void free_signal_struct(struct signal_struct *sig)
static inline void put_signal_struct(struct signal_struct *sig)
{
- if (atomic_dec_and_test(&sig->sigcnt))
+ if (atomic_dec_and_test(&sig->sigcnt)) {
+ sched_autogroup_exit(sig);
free_signal_struct(sig);
+ }
}
void __put_task_struct(struct task_struct *tsk)
@@ -905,6 +907,7 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
posix_cpu_timers_init_group(sig);
tty_audit_fork(sig);
+ sched_autogroup_fork(sig);
sig->oom_adj = current->signal->oom_adj;
sig->oom_score_adj = current->signal->oom_score_adj;
@@ -1315,7 +1318,7 @@ bad_fork_cleanup_mm:
}
bad_fork_cleanup_signal:
if (!(clone_flags & CLONE_THREAD))
- free_signal_struct(p->signal);
+ put_signal_struct(p->signal);
bad_fork_cleanup_sighand:
__cleanup_sighand(p->sighand);
bad_fork_cleanup_fs:
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 5f92acc5f95..91a5fa25054 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -577,7 +577,9 @@ irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action) { }
*/
static int irq_thread(void *data)
{
- struct sched_param param = { .sched_priority = MAX_USER_RT_PRIO/2, };
+ static struct sched_param param = {
+ .sched_priority = MAX_USER_RT_PRIO/2,
+ };
struct irqaction *action = data;
struct irq_desc *desc = irq_to_desc(action->irq);
int wake, oneshot = desc->status & IRQ_ONESHOT;
diff --git a/kernel/kthread.c b/kernel/kthread.c
index ca61bbdd44b..5355cfd44a3 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -148,7 +148,7 @@ struct task_struct *kthread_create(int (*threadfn)(void *data),
wait_for_completion(&create.done);
if (!IS_ERR(create.result)) {
- struct sched_param param = { .sched_priority = 0 };
+ static struct sched_param param = { .sched_priority = 0 };
va_list args;
va_start(args, namefmt);
diff --git a/kernel/mutex.c b/kernel/mutex.c
index 200407c1502..a5889fb28ec 100644
--- a/kernel/mutex.c
+++ b/kernel/mutex.c
@@ -199,7 +199,7 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
* memory barriers as we'll eventually observe the right
* values at the cost of a few extra spins.
*/
- cpu_relax();
+ arch_mutex_cpu_relax();
}
#endif
spin_lock_mutex(&lock->wait_lock, flags);
diff --git a/kernel/printk.c b/kernel/printk.c
index a23315dc449..ab3ffc5b3b6 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -1074,17 +1074,17 @@ static DEFINE_PER_CPU(int, printk_pending);
void printk_tick(void)
{
- if (__get_cpu_var(printk_pending)) {
- __get_cpu_var(printk_pending) = 0;
+ if (__this_cpu_read(printk_pending)) {
+ __this_cpu_write(printk_pending, 0);
wake_up_interruptible(&log_wait);
}
}
int printk_needs_cpu(int cpu)
{
- if (unlikely(cpu_is_offline(cpu)))
+ if (cpu_is_offline(cpu))
printk_tick();
- return per_cpu(printk_pending, cpu);
+ return __this_cpu_read(printk_pending);
}
void wake_up_klogd(void)
diff --git a/kernel/sched.c b/kernel/sched.c
index 260132961a9..04949089e76 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -75,9 +75,11 @@
#include <asm/tlb.h>
#include <asm/irq_regs.h>
+#include <asm/mutex.h>
#include "sched_cpupri.h"
#include "workqueue_sched.h"
+#include "sched_autogroup.h"
#define CREATE_TRACE_POINTS
#include <trace/events/sched.h>
@@ -253,6 +255,8 @@ struct task_group {
/* runqueue "owned" by this group on each cpu */
struct cfs_rq **cfs_rq;
unsigned long shares;
+
+ atomic_t load_weight;
#endif
#ifdef CONFIG_RT_GROUP_SCHED
@@ -268,24 +272,19 @@ struct task_group {
struct task_group *parent;
struct list_head siblings;
struct list_head children;
+
+#ifdef CONFIG_SCHED_AUTOGROUP
+ struct autogroup *autogroup;
+#endif
};
#define root_task_group init_task_group
-/* task_group_lock serializes add/remove of task groups and also changes to
- * a task group's cpu shares.
- */
+/* task_group_lock serializes the addition/removal of task groups */
static DEFINE_SPINLOCK(task_group_lock);
#ifdef CONFIG_FAIR_GROUP_SCHED
-#ifdef CONFIG_SMP
-static int root_task_group_empty(void)
-{
- return list_empty(&root_task_group.children);
-}
-#endif
-
# define INIT_TASK_GROUP_LOAD NICE_0_LOAD
/*
@@ -342,6 +341,7 @@ struct cfs_rq {
* leaf_cfs_rq_list ties together list of leaf cfs_rq's in a cpu. This
* list is used during load balance.
*/
+ int on_list;
struct list_head leaf_cfs_rq_list;
struct task_group *tg; /* group that "owns" this runqueue */
@@ -360,14 +360,17 @@ struct cfs_rq {
unsigned long h_load;
/*
- * this cpu's part of tg->shares
+ * Maintaining per-cpu shares distribution for group scheduling
+ *
+ * load_stamp is the last time we updated the load average
+ * load_last is the last time we updated the load average and saw load
+ * load_unacc_exec_time is currently unaccounted execution time
*/
- unsigned long shares;
+ u64 load_avg;
+ u64 load_period;
+ u64 load_stamp, load_last, load_unacc_exec_time;
- /*
- * load.weight at the time we set shares
- */
- unsigned long rq_weight;
+ unsigned long load_contribution;
#endif
#endif
};
@@ -605,11 +608,14 @@ static inline int cpu_of(struct rq *rq)
*/
static inline struct task_group *task_group(struct task_struct *p)
{
+ struct task_group *tg;
struct cgroup_subsys_state *css;
css = task_subsys_state_check(p, cpu_cgroup_subsys_id,
lockdep_is_held(&task_rq(p)->lock));
- return container_of(css, struct task_group, css);
+ tg = container_of(css, struct task_group, css);
+
+ return autogroup_task_group(p, tg);
}
/* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
@@ -793,20 +799,6 @@ late_initcall(sched_init_debug);
const_debug unsigned int sysctl_sched_nr_migrate = 32;
/*
- * ratelimit for updating the group shares.
- * default: 0.25ms
- */
-unsigned int sysctl_sched_shares_ratelimit = 250000;
-unsigned int normalized_sysctl_sched_shares_ratelimit = 250000;
-
-/*
- * Inject some fuzzyness into changing the per-cpu group shares
- * this avoids remote rq-locks at the expense of fairness.
- * default: 4
- */
-unsigned int sysctl_sched_shares_thresh = 4;
-
-/*
* period over which we average the RT time consumption, measured
* in ms.
*
@@ -1355,6 +1347,12 @@ static inline void update_load_sub(struct load_weight *lw, unsigned long dec)
lw->inv_weight = 0;
}
+static inline void update_load_set(struct load_weight *lw, unsigned long w)
+{
+ lw->weight = w;
+ lw->inv_weight = 0;
+}
+
/*
* To aid in avoiding the subversion of "niceness" due to uneven distribution
* of tasks with abnormal "nice" values across CPUs the contribution that
@@ -1543,101 +1541,6 @@ static unsigned long cpu_avg_load_per_task(int cpu)
#ifdef CONFIG_FAIR_GROUP_SCHED
-static __read_mostly unsigned long __percpu *update_shares_data;
-
-static void __set_se_shares(struct sched_entity *se, unsigned long shares);
-
-/*
- * Calculate and set the cpu's group shares.
- */
-static void update_group_shares_cpu(struct task_group *tg, int cpu,
- unsigned long sd_shares,
- unsigned long sd_rq_weight,
- unsigned long *usd_rq_weight)
-{
- unsigned long shares, rq_weight;
- int boost = 0;
-
- rq_weight = usd_rq_weight[cpu];
- if (!rq_weight) {
- boost = 1;
- rq_weight = NICE_0_LOAD;
- }
-
- /*
- * \Sum_j shares_j * rq_weight_i
- * shares_i = -----------------------------
- * \Sum_j rq_weight_j
- */
- shares = (sd_shares * rq_weight) / sd_rq_weight;
- shares = clamp_t(unsigned long, shares, MIN_SHARES, MAX_SHARES);
-
- if (abs(shares - tg->se[cpu]->load.weight) >
- sysctl_sched_shares_thresh) {
- struct rq *rq = cpu_rq(cpu);
- unsigned long flags;
-
- raw_spin_lock_irqsave(&rq->lock, flags);
- tg->cfs_rq[cpu]->rq_weight = boost ? 0 : rq_weight;
- tg->cfs_rq[cpu]->shares = boost ? 0 : shares;
- __set_se_shares(tg->se[cpu], shares);
- raw_spin_unlock_irqrestore(&rq->lock, flags);
- }
-}
-
-/*
- * Re-compute the task group their per cpu shares over the given domain.
- * This needs to be done in a bottom-up fashion because the rq weight of a
- * parent group depends on the shares of its child groups.
- */
-static int tg_shares_up(struct task_group *tg, void *data)
-{
- unsigned long weight, rq_weight = 0, sum_weight = 0, shares = 0;
- unsigned long *usd_rq_weight;
- struct sched_domain *sd = data;
- unsigned long flags;
- int i;
-
- if (!tg->se[0])
- return 0;
-
- local_irq_save(flags);
- usd_rq_weight = per_cpu_ptr(update_shares_data, smp_processor_id());
-
- for_each_cpu(i, sched_domain_span(sd)) {
- weight = tg->cfs_rq[i]->load.weight;
- usd_rq_weight[i] = weight;
-
- rq_weight += weight;
- /*
- * If there are currently no tasks on the cpu pretend there
- * is one of average load so that when a new task gets to
- * run here it will not get delayed by group starvation.
- */
- if (!weight)
- weight = NICE_0_LOAD;
-
- sum_weight += weight;
- shares += tg->cfs_rq[i]->shares;
- }
-
- if (!rq_weight)
- rq_weight = sum_weight;
-
- if ((!shares && rq_weight) || shares > tg->shares)
- shares = tg->shares;
-
- if (!sd->parent || !(sd->parent->flags & SD_LOAD_BALANCE))
- shares = tg->shares;
-
- for_each_cpu(i, sched_domain_span(sd))
- update_group_shares_cpu(tg, i, shares, rq_weight, usd_rq_weight);
-
- local_irq_restore(flags);
-
- return 0;
-}
-
/*
* Compute the cpu's hierarchical load factor for each task group.
* This needs to be done in a top-down fashion because the load of a child
@@ -1652,7 +1555,7 @@ static int tg_load_down(struct task_group *tg, void *data)
load = cpu_rq(cpu)->load.weight;
} else {
load = tg->parent->cfs_rq[cpu]->h_load;
- load *= tg->cfs_rq[cpu]->shares;
+ load *= tg->se[cpu]->load.weight;
load /= tg->parent->cfs_rq[cpu]->load.weight + 1;
}
@@ -1661,34 +1564,11 @@ static int tg_load_down(struct task_group *tg, void *data)
return 0;
}
-static void update_shares(struct sched_domain *sd)
-{
- s64 elapsed;
- u64 now;
-
- if (root_task_group_empty())
- return;
-
- now = local_clock();
- elapsed = now - sd->last_update;
-
- if (elapsed >= (s64)(u64)sysctl_sched_shares_ratelimit) {
- sd->last_update = now;
- walk_tg_tree(tg_nop, tg_shares_up, sd);
- }
-}
-
static void update_h_load(long cpu)
{
walk_tg_tree(tg_load_down, tg_nop, (void *)cpu);
}
-#else
-
-static inline void update_shares(struct sched_domain *sd)
-{
-}
-
#endif
#ifdef CONFIG_PREEMPT
@@ -1810,15 +1690,6 @@ static void double_rq_unlock(struct rq *rq1, struct rq *rq2)
#endif
-#ifdef CONFIG_FAIR_GROUP_SCHED
-static void cfs_rq_set_shares(struct cfs_rq *cfs_rq, unsigned long shares)
-{
-#ifdef CONFIG_SMP
- cfs_rq->shares = shares;
-#endif
-}
-#endif
-
static void calc_load_account_idle(struct rq *this_rq);
static void update_sysctl(void);
static int get_update_sysctl_factor(void);
@@ -2063,6 +1934,7 @@ static void update_rq_clock_task(struct rq *rq, s64 delta)
#include "sched_idletask.c"
#include "sched_fair.c"
#include "sched_rt.c"
+#include "sched_autogroup.c"
#include "sched_stoptask.c"
#ifdef CONFIG_SCHED_DEBUG
# include "sched_debug.c"
@@ -2255,10 +2127,8 @@ 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, int dest_cpu)
+static bool migrate_task(struct task_struct *p, struct rq *rq)
{
- struct rq *rq = task_rq(p);
-
/*
* If the task is not on a runqueue (and not running), then
* the next wake-up will properly place the task.
@@ -2438,18 +2308,15 @@ static int select_fallback_rq(int cpu, struct task_struct *p)
return dest_cpu;
/* No more Mr. Nice Guy. */
- if (unlikely(dest_cpu >= nr_cpu_ids)) {
- dest_cpu = cpuset_cpus_allowed_fallback(p);
- /*
- * Don't tell them about moving exiting tasks or
- * kernel threads (both mm NULL), since they never
- * leave kernel.
- */
- if (p->mm && printk_ratelimit()) {
- printk(KERN_INFO "process %d (%s) no "
- "longer affine to cpu%d\n",
- task_pid_nr(p), p->comm, cpu);
- }
+ dest_cpu = cpuset_cpus_allowed_fallback(p);
+ /*
+ * Don't tell them about moving exiting tasks or
+ * kernel threads (both mm NULL), since they never
+ * leave kernel.
+ */
+ if (p->mm && printk_ratelimit()) {
+ printk(KERN_INFO "process %d (%s) no longer affine to cpu%d\n",
+ task_pid_nr(p), p->comm, cpu);
}
return dest_cpu;
@@ -2785,7 +2652,9 @@ void sched_fork(struct task_struct *p, int clone_flags)
/* Want to start with kernel preemption disabled. */
task_thread_info(p)->preempt_count = 1;
#endif
+#ifdef CONFIG_SMP
plist_node_init(&p->pushable_tasks, MAX_PRIO);
+#endif
put_cpu();
}
@@ -3549,7 +3418,7 @@ void sched_exec(void)
* 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, dest_cpu)) {
+ likely(cpu_active(dest_cpu)) && migrate_task(p, rq)) {
struct migration_arg arg = { p, dest_cpu };
task_rq_unlock(rq, &flags);
@@ -4214,7 +4083,7 @@ int mutex_spin_on_owner(struct mutex *lock, struct thread_info *owner)
if (task_thread_info(rq->curr) != owner || need_resched())
return 0;
- cpu_relax();
+ arch_mutex_cpu_relax();
}
return 1;
@@ -4526,7 +4395,7 @@ EXPORT_SYMBOL(wait_for_completion_interruptible);
* This waits for either a completion of a specific task to be signaled or for a
* specified timeout to expire. It is interruptible. The timeout is in jiffies.
*/
-unsigned long __sched
+long __sched
wait_for_completion_interruptible_timeout(struct completion *x,
unsigned long timeout)
{
@@ -4559,7 +4428,7 @@ EXPORT_SYMBOL(wait_for_completion_killable);
* signaled or for a specified timeout to expire. It can be
* interrupted by a kill signal. The timeout is in jiffies.
*/
-unsigned long __sched
+long __sched
wait_for_completion_killable_timeout(struct completion *x,
unsigned long timeout)
{
@@ -4901,7 +4770,7 @@ static bool check_same_owner(struct task_struct *p)
}
static int __sched_setscheduler(struct task_struct *p, int policy,
- struct sched_param *param, bool user)
+ const struct sched_param *param, bool user)
{
int retval, oldprio, oldpolicy = -1, on_rq, running;
unsigned long flags;
@@ -5056,7 +4925,7 @@ recheck:
* NOTE that the task may be already dead.
*/
int sched_setscheduler(struct task_struct *p, int policy,
- struct sched_param *param)
+ const struct sched_param *param)
{
return __sched_setscheduler(p, policy, param, true);
}
@@ -5074,7 +4943,7 @@ EXPORT_SYMBOL_GPL(sched_setscheduler);
* but our caller might not have that capability.
*/
int sched_setscheduler_nocheck(struct task_struct *p, int policy,
- struct sched_param *param)
+ const struct sched_param *param)
{
return __sched_setscheduler(p, policy, param, false);
}
@@ -5590,7 +5459,7 @@ void sched_show_task(struct task_struct *p)
unsigned state;
state = p->state ? __ffs(p->state) + 1 : 0;
- printk(KERN_INFO "%-13.13s %c", p->comm,
+ printk(KERN_INFO "%-15.15s %c", p->comm,
state < sizeof(stat_nam) - 1 ? stat_nam[state] : '?');
#if BITS_PER_LONG == 32
if (state == TASK_RUNNING)
@@ -5754,7 +5623,6 @@ static void update_sysctl(void)
SET_SYSCTL(sched_min_granularity);
SET_SYSCTL(sched_latency);
SET_SYSCTL(sched_wakeup_granularity);
- SET_SYSCTL(sched_shares_ratelimit);
#undef SET_SYSCTL
}
@@ -5830,7 +5698,7 @@ again:
goto out;
dest_cpu = cpumask_any_and(cpu_active_mask, new_mask);
- if (migrate_task(p, dest_cpu)) {
+ if (migrate_task(p, rq)) {
struct migration_arg arg = { p, dest_cpu };
/* Need help from migration thread: drop lock and wait. */
task_rq_unlock(rq, &flags);
@@ -5912,29 +5780,20 @@ static int migration_cpu_stop(void *data)
}
#ifdef CONFIG_HOTPLUG_CPU
+
/*
- * Figure out where task on dead CPU should go, use force if necessary.
+ * Ensures that the idle task is using init_mm right before its cpu goes
+ * offline.
*/
-void move_task_off_dead_cpu(int dead_cpu, struct task_struct *p)
+void idle_task_exit(void)
{
- struct rq *rq = cpu_rq(dead_cpu);
- int needs_cpu, uninitialized_var(dest_cpu);
- unsigned long flags;
+ struct mm_struct *mm = current->active_mm;
- local_irq_save(flags);
+ BUG_ON(cpu_online(smp_processor_id()));
- raw_spin_lock(&rq->lock);
- needs_cpu = (task_cpu(p) == dead_cpu) && (p->state != TASK_WAKING);
- if (needs_cpu)
- dest_cpu = select_fallback_rq(dead_cpu, p);
- raw_spin_unlock(&rq->lock);
- /*
- * It can only fail if we race with set_cpus_allowed(),
- * in the racer should migrate the task anyway.
- */
- if (needs_cpu)
- __migrate_task(p, dead_cpu, dest_cpu);
- local_irq_restore(flags);
+ if (mm != &init_mm)
+ switch_mm(mm, &init_mm, current);
+ mmdrop(mm);
}
/*
@@ -5947,128 +5806,69 @@ void move_task_off_dead_cpu(int dead_cpu, struct task_struct *p)
static void migrate_nr_uninterruptible(struct rq *rq_src)
{
struct rq *rq_dest = cpu_rq(cpumask_any(cpu_active_mask));
- unsigned long flags;
- local_irq_save(flags);
- double_rq_lock(rq_src, rq_dest);
rq_dest->nr_uninterruptible += rq_src->nr_uninterruptible;
rq_src->nr_uninterruptible = 0;
- double_rq_unlock(rq_src, rq_dest);
- local_irq_restore(flags);
-}
-
-/* Run through task list and migrate tasks from the dead cpu. */
-static void migrate_live_tasks(int src_cpu)
-{
- struct task_struct *p, *t;
-
- read_lock(&tasklist_lock);
-
- do_each_thread(t, p) {
- if (p == current)
- continue;
-
- if (task_cpu(p) == src_cpu)
- move_task_off_dead_cpu(src_cpu, p);
- } while_each_thread(t, p);
-
- read_unlock(&tasklist_lock);
}
/*
- * Schedules idle task to be the next runnable task on current CPU.
- * It does so by boosting its priority to highest possible.
- * Used by CPU offline code.
+ * remove the tasks which were accounted by rq from calc_load_tasks.
*/
-void sched_idle_next(void)
+static void calc_global_load_remove(struct rq *rq)
{
- int this_cpu = smp_processor_id();
- struct rq *rq = cpu_rq(this_cpu);
- struct task_struct *p = rq->idle;
- unsigned long flags;
-
- /* cpu has to be offline */
- BUG_ON(cpu_online(this_cpu));
-
- /*
- * Strictly not necessary since rest of the CPUs are stopped by now
- * and interrupts disabled on the current cpu.
- */
- raw_spin_lock_irqsave(&rq->lock, flags);
-
- __setscheduler(rq, p, SCHED_FIFO, MAX_RT_PRIO-1);
-
- activate_task(rq, p, 0);
-
- raw_spin_unlock_irqrestore(&rq->lock, flags);
+ atomic_long_sub(rq->calc_load_active, &calc_load_tasks);
+ rq->calc_load_active = 0;
}
/*
- * Ensures that the idle task is using init_mm right before its cpu goes
- * offline.
+ * Migrate all tasks from the rq, sleeping tasks will be migrated by
+ * try_to_wake_up()->select_task_rq().
+ *
+ * Called with rq->lock held even though we'er in stop_machine() and
+ * there's no concurrency possible, we hold the required locks anyway
+ * because of lock validation efforts.
*/
-void idle_task_exit(void)
-{
- struct mm_struct *mm = current->active_mm;
-
- BUG_ON(cpu_online(smp_processor_id()));
-
- if (mm != &init_mm)
- switch_mm(mm, &init_mm, current);
- mmdrop(mm);
-}
-
-/* called under rq->lock with disabled interrupts */
-static void migrate_dead(unsigned int dead_cpu, struct task_struct *p)
+static void migrate_tasks(unsigned int dead_cpu)
{
struct rq *rq = cpu_rq(dead_cpu);
-
- /* Must be exiting, otherwise would be on tasklist. */
- BUG_ON(!p->exit_state);
-
- /* Cannot have done final schedule yet: would have vanished. */
- BUG_ON(p->state == TASK_DEAD);
-
- get_task_struct(p);
+ struct task_struct *next, *stop = rq->stop;
+ int dest_cpu;
/*
- * Drop lock around migration; if someone else moves it,
- * that's OK. No task can be added to this CPU, so iteration is
- * fine.
+ * Fudge the rq selection such that the below task selection loop
+ * doesn't get stuck on the currently eligible stop task.
+ *
+ * We're currently inside stop_machine() and the rq is either stuck
+ * in the stop_machine_cpu_stop() loop, or we're executing this code,
+ * either way we should never end up calling schedule() until we're
+ * done here.
*/
- raw_spin_unlock_irq(&rq->lock);
- move_task_off_dead_cpu(dead_cpu, p);
- raw_spin_lock_irq(&rq->lock);
-
- put_task_struct(p);
-}
-
-/* release_task() removes task from tasklist, so we won't find dead tasks. */
-static void migrate_dead_tasks(unsigned int dead_cpu)
-{
- struct rq *rq = cpu_rq(dead_cpu);
- struct task_struct *next;
+ rq->stop = NULL;
for ( ; ; ) {
- if (!rq->nr_running)
+ /*
+ * There's this thread running, bail when that's the only
+ * remaining thread.
+ */
+ if (rq->nr_running == 1)
break;
+
next = pick_next_task(rq);
- if (!next)
- break;
+ BUG_ON(!next);
next->sched_class->put_prev_task(rq, next);
- migrate_dead(dead_cpu, next);
+ /* Find suitable destination for @next, with force if needed. */
+ dest_cpu = select_fallback_rq(dead_cpu, next);
+ raw_spin_unlock(&rq->lock);
+
+ __migrate_task(next, dead_cpu, dest_cpu);
+
+ raw_spin_lock(&rq->lock);
}
-}
-/*
- * remove the tasks which were accounted by rq from calc_load_tasks.
- */
-static void calc_global_load_remove(struct rq *rq)
-{
- atomic_long_sub(rq->calc_load_active, &calc_load_tasks);
- rq->calc_load_active = 0;
+ rq->stop = stop;
}
+
#endif /* CONFIG_HOTPLUG_CPU */
#if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_SYSCTL)
@@ -6278,15 +6078,13 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
unsigned long flags;
struct rq *rq = cpu_rq(cpu);
- switch (action) {
+ switch (action & ~CPU_TASKS_FROZEN) {
case CPU_UP_PREPARE:
- case CPU_UP_PREPARE_FROZEN:
rq->calc_load_update = calc_load_update;
break;
case CPU_ONLINE:
- case CPU_ONLINE_FROZEN:
/* Update our root-domain */
raw_spin_lock_irqsave(&rq->lock, flags);
if (rq->rd) {
@@ -6298,30 +6096,19 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
break;
#ifdef CONFIG_HOTPLUG_CPU
- case CPU_DEAD:
- case CPU_DEAD_FROZEN:
- migrate_live_tasks(cpu);
- /* Idle task back to normal (off runqueue, low prio) */
- raw_spin_lock_irq(&rq->lock);
- deactivate_task(rq, rq->idle, 0);
- __setscheduler(rq, rq->idle, SCHED_NORMAL, 0);
- rq->idle->sched_class = &idle_sched_class;
- migrate_dead_tasks(cpu);
- raw_spin_unlock_irq(&rq->lock);
- migrate_nr_uninterruptible(rq);
- BUG_ON(rq->nr_running != 0);
- calc_global_load_remove(rq);
- break;
-
case CPU_DYING:
- case CPU_DYING_FROZEN:
/* Update our root-domain */
raw_spin_lock_irqsave(&rq->lock, flags);
if (rq->rd) {
BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span));
set_rq_offline(rq);
}
+ migrate_tasks(cpu);
+ BUG_ON(rq->nr_running != 1); /* the migration thread */
raw_spin_unlock_irqrestore(&rq->lock, flags);
+
+ migrate_nr_uninterruptible(rq);
+ calc_global_load_remove(rq);
break;
#endif
}
@@ -8052,15 +7839,13 @@ static void init_rt_rq(struct rt_rq *rt_rq, struct rq *rq)
#ifdef CONFIG_FAIR_GROUP_SCHED
static void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
- struct sched_entity *se, int cpu, int add,
+ struct sched_entity *se, int cpu,
struct sched_entity *parent)
{
struct rq *rq = cpu_rq(cpu);
tg->cfs_rq[cpu] = cfs_rq;
init_cfs_rq(cfs_rq, rq);
cfs_rq->tg = tg;
- if (add)
- list_add(&cfs_rq->leaf_cfs_rq_list, &rq->leaf_cfs_rq_list);
tg->se[cpu] = se;
/* se could be NULL for init_task_group */
@@ -8073,15 +7858,14 @@ static void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
se->cfs_rq = parent->my_q;
se->my_q = cfs_rq;
- se->load.weight = tg->shares;
- se->load.inv_weight = 0;
+ update_load_set(&se->load, 0);
se->parent = parent;
}
#endif
#ifdef CONFIG_RT_GROUP_SCHED
static void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
- struct sched_rt_entity *rt_se, int cpu, int add,
+ struct sched_rt_entity *rt_se, int cpu,
struct sched_rt_entity *parent)
{
struct rq *rq = cpu_rq(cpu);
@@ -8090,8 +7874,6 @@ static void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
init_rt_rq(rt_rq, rq);
rt_rq->tg = tg;
rt_rq->rt_runtime = tg->rt_bandwidth.rt_runtime;
- if (add)
- list_add(&rt_rq->leaf_rt_rq_list, &rq->leaf_rt_rq_list);
tg->rt_se[cpu] = rt_se;
if (!rt_se)
@@ -8164,13 +7946,9 @@ void __init sched_init(void)
#ifdef CONFIG_CGROUP_SCHED
list_add(&init_task_group.list, &task_groups);
INIT_LIST_HEAD(&init_task_group.children);
-
+ autogroup_init(&init_task);
#endif /* CONFIG_CGROUP_SCHED */
-#if defined CONFIG_FAIR_GROUP_SCHED && defined CONFIG_SMP
- update_shares_data = __alloc_percpu(nr_cpu_ids * sizeof(unsigned long),
- __alignof__(unsigned long));
-#endif
for_each_possible_cpu(i) {
struct rq *rq;
@@ -8184,7 +7962,6 @@ void __init sched_init(void)
#ifdef CONFIG_FAIR_GROUP_SCHED
init_task_group.shares = init_task_group_load;
INIT_LIST_HEAD(&rq->leaf_cfs_rq_list);
-#ifdef CONFIG_CGROUP_SCHED
/*
* How much cpu bandwidth does init_task_group get?
*
@@ -8204,16 +7981,13 @@ void __init sched_init(void)
* We achieve this by letting init_task_group's tasks sit
* directly in rq->cfs (i.e init_task_group->se[] = NULL).
*/
- init_tg_cfs_entry(&init_task_group, &rq->cfs, NULL, i, 1, NULL);
-#endif
+ init_tg_cfs_entry(&init_task_group, &rq->cfs, NULL, i, NULL);
#endif /* CONFIG_FAIR_GROUP_SCHED */
rq->rt.rt_runtime = def_rt_bandwidth.rt_runtime;
#ifdef CONFIG_RT_GROUP_SCHED
INIT_LIST_HEAD(&rq->leaf_rt_rq_list);
-#ifdef CONFIG_CGROUP_SCHED
- init_tg_rt_entry(&init_task_group, &rq->rt, NULL, i, 1, NULL);
-#endif
+ init_tg_rt_entry(&init_task_group, &rq->rt, NULL, i, NULL);
#endif
for (j = 0; j < CPU_LOAD_IDX_MAX; j++)
@@ -8486,7 +8260,7 @@ int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent)
if (!se)
goto err_free_rq;
- init_tg_cfs_entry(tg, cfs_rq, se, i, 0, parent->se[i]);
+ init_tg_cfs_entry(tg, cfs_rq, se, i, parent->se[i]);
}
return 1;
@@ -8497,15 +8271,21 @@ err:
return 0;
}
-static inline void register_fair_sched_group(struct task_group *tg, int cpu)
-{
- list_add_rcu(&tg->cfs_rq[cpu]->leaf_cfs_rq_list,
- &cpu_rq(cpu)->leaf_cfs_rq_list);
-}
-
static inline void unregister_fair_sched_group(struct task_group *tg, int cpu)
{
- list_del_rcu(&tg->cfs_rq[cpu]->leaf_cfs_rq_list);
+ struct rq *rq = cpu_rq(cpu);
+ unsigned long flags;
+
+ /*
+ * Only empty task groups can be destroyed; so we can speculatively
+ * check on_list without danger of it being re-added.
+ */
+ if (!tg->cfs_rq[cpu]->on_list)
+ return;
+
+ raw_spin_lock_irqsave(&rq->lock, flags);
+ list_del_leaf_cfs_rq(tg->cfs_rq[cpu]);
+ raw_spin_unlock_irqrestore(&rq->lock, flags);
}
#else /* !CONFG_FAIR_GROUP_SCHED */
static inline void free_fair_sched_group(struct task_group *tg)
@@ -8518,10 +8298,6 @@ int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent)
return 1;
}
-static inline void register_fair_sched_group(struct task_group *tg, int cpu)
-{
-}
-
static inline void unregister_fair_sched_group(struct task_group *tg, int cpu)
{
}
@@ -8576,7 +8352,7 @@ int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent)
if (!rt_se)
goto err_free_rq;
- init_tg_rt_entry(tg, rt_rq, rt_se, i, 0, parent->rt_se[i]);
+ init_tg_rt_entry(tg, rt_rq, rt_se, i, parent->rt_se[i]);
}
return 1;
@@ -8586,17 +8362,6 @@ err_free_rq:
err:
return 0;
}
-
-static inline void register_rt_sched_group(struct task_group *tg, int cpu)
-{
- list_add_rcu(&tg->rt_rq[cpu]->leaf_rt_rq_list,
- &cpu_rq(cpu)->leaf_rt_rq_list);
-}
-
-static inline void unregister_rt_sched_group(struct task_group *tg, int cpu)
-{
- list_del_rcu(&tg->rt_rq[cpu]->leaf_rt_rq_list);
-}
#else /* !CONFIG_RT_GROUP_SCHED */
static inline void free_rt_sched_group(struct task_group *tg)
{
@@ -8607,14 +8372,6 @@ int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent)
{
return 1;
}
-
-static inline void register_rt_sched_group(struct task_group *tg, int cpu)
-{
-}
-
-static inline void unregister_rt_sched_group(struct task_group *tg, int cpu)
-{
-}
#endif /* CONFIG_RT_GROUP_SCHED */
#ifdef CONFIG_CGROUP_SCHED
@@ -8630,7 +8387,6 @@ struct task_group *sched_create_group(struct task_group *parent)
{
struct task_group *tg;
unsigned long flags;
- int i;
tg = kzalloc(sizeof(*tg), GFP_KERNEL);
if (!tg)
@@ -8643,10 +8399,6 @@ struct task_group *sched_create_group(struct task_group *parent)
goto err;
spin_lock_irqsave(&task_group_lock, flags);
- for_each_possible_cpu(i) {
- register_fair_sched_group(tg, i);
- register_rt_sched_group(tg, i);
- }
list_add_rcu(&tg->list, &task_groups);
WARN_ON(!parent); /* root should already exist */
@@ -8676,11 +8428,11 @@ void sched_destroy_group(struct task_group *tg)
unsigned long flags;
int i;
- spin_lock_irqsave(&task_group_lock, flags);
- for_each_possible_cpu(i) {
+ /* end participation in shares distribution */
+ for_each_possible_cpu(i)
unregister_fair_sched_group(tg, i);
- unregister_rt_sched_group(tg, i);
- }
+
+ spin_lock_irqsave(&task_group_lock, flags);
list_del_rcu(&tg->list);
list_del_rcu(&tg->siblings);
spin_unlock_irqrestore(&task_group_lock, flags);
@@ -8727,33 +8479,6 @@ void sched_move_task(struct task_struct *tsk)
#endif /* CONFIG_CGROUP_SCHED */
#ifdef CONFIG_FAIR_GROUP_SCHED
-static void __set_se_shares(struct sched_entity *se, unsigned long shares)
-{
- struct cfs_rq *cfs_rq = se->cfs_rq;
- int on_rq;
-
- on_rq = se->on_rq;
- if (on_rq)
- dequeue_entity(cfs_rq, se, 0);
-
- se->load.weight = shares;
- se->load.inv_weight = 0;
-
- if (on_rq)
- enqueue_entity(cfs_rq, se, 0);
-}
-
-static void set_se_shares(struct sched_entity *se, unsigned long shares)
-{
- struct cfs_rq *cfs_rq = se->cfs_rq;
- struct rq *rq = cfs_rq->rq;
- unsigned long flags;
-
- raw_spin_lock_irqsave(&rq->lock, flags);
- __set_se_shares(se, shares);
- raw_spin_unlock_irqrestore(&rq->lock, flags);
-}
-
static DEFINE_MUTEX(shares_mutex);
int sched_group_set_shares(struct task_group *tg, unsigned long shares)
@@ -8776,37 +8501,19 @@ int sched_group_set_shares(struct task_group *tg, unsigned long shares)
if (tg->shares == shares)
goto done;
- spin_lock_irqsave(&task_group_lock, flags);
- for_each_possible_cpu(i)
- unregister_fair_sched_group(tg, i);
- list_del_rcu(&tg->siblings);
- spin_unlock_irqrestore(&task_group_lock, flags);
-
- /* wait for any ongoing reference to this group to finish */
- synchronize_sched();
-
- /*
- * Now we are free to modify the group's share on each cpu
- * w/o tripping rebalance_share or load_balance_fair.
- */
tg->shares = shares;
for_each_possible_cpu(i) {
- /*
- * force a rebalance
- */
- cfs_rq_set_shares(tg->cfs_rq[i], 0);
- set_se_shares(tg->se[i], shares);
+ struct rq *rq = cpu_rq(i);
+ struct sched_entity *se;
+
+ se = tg->se[i];
+ /* Propagate contribution to hierarchy */
+ raw_spin_lock_irqsave(&rq->lock, flags);
+ for_each_sched_entity(se)
+ update_cfs_shares(group_cfs_rq(se), 0);
+ raw_spin_unlock_irqrestore(&rq->lock, flags);
}
- /*
- * Enable load balance activity on this group, by inserting it back on
- * each cpu's rq->leaf_cfs_rq_list.
- */
- spin_lock_irqsave(&task_group_lock, flags);
- for_each_possible_cpu(i)
- register_fair_sched_group(tg, i);
- list_add_rcu(&tg->siblings, &tg->parent->children);
- spin_unlock_irqrestore(&task_group_lock, flags);
done:
mutex_unlock(&shares_mutex);
return 0;
diff --git a/kernel/sched_autogroup.c b/kernel/sched_autogroup.c
new file mode 100644
index 00000000000..c80fedcd476
--- /dev/null
+++ b/kernel/sched_autogroup.c
@@ -0,0 +1,238 @@
+#ifdef CONFIG_SCHED_AUTOGROUP
+
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/kallsyms.h>
+#include <linux/utsname.h>
+
+unsigned int __read_mostly sysctl_sched_autogroup_enabled = 1;
+static struct autogroup autogroup_default;
+static atomic_t autogroup_seq_nr;
+
+static void autogroup_init(struct task_struct *init_task)
+{
+ autogroup_default.tg = &init_task_group;
+ init_task_group.autogroup = &autogroup_default;
+ kref_init(&autogroup_default.kref);
+ init_rwsem(&autogroup_default.lock);
+ init_task->signal->autogroup = &autogroup_default;
+}
+
+static inline void autogroup_free(struct task_group *tg)
+{
+ kfree(tg->autogroup);
+}
+
+static inline void autogroup_destroy(struct kref *kref)
+{
+ struct autogroup *ag = container_of(kref, struct autogroup, kref);
+
+ sched_destroy_group(ag->tg);
+}
+
+static inline void autogroup_kref_put(struct autogroup *ag)
+{
+ kref_put(&ag->kref, autogroup_destroy);
+}
+
+static inline struct autogroup *autogroup_kref_get(struct autogroup *ag)
+{
+ kref_get(&ag->kref);
+ return ag;
+}
+
+static inline struct autogroup *autogroup_task_get(struct task_struct *p)
+{
+ struct autogroup *ag;
+ unsigned long flags;
+
+ if (!lock_task_sighand(p, &flags))
+ return autogroup_kref_get(&autogroup_default);
+
+ ag = autogroup_kref_get(p->signal->autogroup);
+ unlock_task_sighand(p, &flags);
+
+ return ag;
+}
+
+static inline struct autogroup *autogroup_create(void)
+{
+ struct autogroup *ag = kzalloc(sizeof(*ag), GFP_KERNEL);
+ struct task_group *tg;
+
+ if (!ag)
+ goto out_fail;
+
+ tg = sched_create_group(&init_task_group);
+
+ if (IS_ERR(tg))
+ goto out_free;
+
+ kref_init(&ag->kref);
+ init_rwsem(&ag->lock);
+ ag->id = atomic_inc_return(&autogroup_seq_nr);
+ ag->tg = tg;
+ tg->autogroup = ag;
+
+ return ag;
+
+out_free:
+ kfree(ag);
+out_fail:
+ if (printk_ratelimit()) {
+ printk(KERN_WARNING "autogroup_create: %s failure.\n",
+ ag ? "sched_create_group()" : "kmalloc()");
+ }
+
+ return autogroup_kref_get(&autogroup_default);
+}
+
+static inline bool
+task_wants_autogroup(struct task_struct *p, struct task_group *tg)
+{
+ if (tg != &root_task_group)
+ return false;
+
+ if (p->sched_class != &fair_sched_class)
+ return false;
+
+ /*
+ * We can only assume the task group can't go away on us if
+ * autogroup_move_group() can see us on ->thread_group list.
+ */
+ if (p->flags & PF_EXITING)
+ return false;
+
+ return true;
+}
+
+static inline struct task_group *
+autogroup_task_group(struct task_struct *p, struct task_group *tg)
+{
+ int enabled = ACCESS_ONCE(sysctl_sched_autogroup_enabled);
+
+ if (enabled && task_wants_autogroup(p, tg))
+ return p->signal->autogroup->tg;
+
+ return tg;
+}
+
+static void
+autogroup_move_group(struct task_struct *p, struct autogroup *ag)
+{
+ struct autogroup *prev;
+ struct task_struct *t;
+ unsigned long flags;
+
+ BUG_ON(!lock_task_sighand(p, &flags));
+
+ prev = p->signal->autogroup;
+ if (prev == ag) {
+ unlock_task_sighand(p, &flags);
+ return;
+ }
+
+ p->signal->autogroup = autogroup_kref_get(ag);
+
+ t = p;
+ do {
+ sched_move_task(t);
+ } while_each_thread(p, t);
+
+ unlock_task_sighand(p, &flags);
+ autogroup_kref_put(prev);
+}
+
+/* Allocates GFP_KERNEL, cannot be called under any spinlock */
+void sched_autogroup_create_attach(struct task_struct *p)
+{
+ struct autogroup *ag = autogroup_create();
+
+ autogroup_move_group(p, ag);
+ /* drop extra refrence added by autogroup_create() */
+ autogroup_kref_put(ag);
+}
+EXPORT_SYMBOL(sched_autogroup_create_attach);
+
+/* Cannot be called under siglock. Currently has no users */
+void sched_autogroup_detach(struct task_struct *p)
+{
+ autogroup_move_group(p, &autogroup_default);
+}
+EXPORT_SYMBOL(sched_autogroup_detach);
+
+void sched_autogroup_fork(struct signal_struct *sig)
+{
+ sig->autogroup = autogroup_task_get(current);
+}
+
+void sched_autogroup_exit(struct signal_struct *sig)
+{
+ autogroup_kref_put(sig->autogroup);
+}
+
+static int __init setup_autogroup(char *str)
+{
+ sysctl_sched_autogroup_enabled = 0;
+
+ return 1;
+}
+
+__setup("noautogroup", setup_autogroup);
+
+#ifdef CONFIG_PROC_FS
+
+int proc_sched_autogroup_set_nice(struct task_struct *p, int *nice)
+{
+ static unsigned long next = INITIAL_JIFFIES;
+ struct autogroup *ag;
+ int err;
+
+ if (*nice < -20 || *nice > 19)
+ return -EINVAL;
+
+ err = security_task_setnice(current, *nice);
+ if (err)
+ return err;
+
+ if (*nice < 0 && !can_nice(current, *nice))
+ return -EPERM;
+
+ /* this is a heavy operation taking global locks.. */
+ if (!capable(CAP_SYS_ADMIN) && time_before(jiffies, next))
+ return -EAGAIN;
+
+ next = HZ / 10 + jiffies;
+ ag = autogroup_task_get(p);
+
+ down_write(&ag->lock);
+ err = sched_group_set_shares(ag->tg, prio_to_weight[*nice + 20]);
+ if (!err)
+ ag->nice = *nice;
+ up_write(&ag->lock);
+
+ autogroup_kref_put(ag);
+
+ return err;
+}
+
+void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m)
+{
+ struct autogroup *ag = autogroup_task_get(p);
+
+ down_read(&ag->lock);
+ seq_printf(m, "/autogroup-%ld nice %d\n", ag->id, ag->nice);
+ up_read(&ag->lock);
+
+ autogroup_kref_put(ag);
+}
+#endif /* CONFIG_PROC_FS */
+
+#ifdef CONFIG_SCHED_DEBUG
+static inline int autogroup_path(struct task_group *tg, char *buf, int buflen)
+{
+ return snprintf(buf, buflen, "%s-%ld", "/autogroup", tg->autogroup->id);
+}
+#endif /* CONFIG_SCHED_DEBUG */
+
+#endif /* CONFIG_SCHED_AUTOGROUP */
diff --git a/kernel/sched_autogroup.h b/kernel/sched_autogroup.h
new file mode 100644
index 00000000000..5358e241cb2
--- /dev/null
+++ b/kernel/sched_autogroup.h
@@ -0,0 +1,32 @@
+#ifdef CONFIG_SCHED_AUTOGROUP
+
+struct autogroup {
+ struct kref kref;
+ struct task_group *tg;
+ struct rw_semaphore lock;
+ unsigned long id;
+ int nice;
+};
+
+static inline struct task_group *
+autogroup_task_group(struct task_struct *p, struct task_group *tg);
+
+#else /* !CONFIG_SCHED_AUTOGROUP */
+
+static inline void autogroup_init(struct task_struct *init_task) { }
+static inline void autogroup_free(struct task_group *tg) { }
+
+static inline struct task_group *
+autogroup_task_group(struct task_struct *p, struct task_group *tg)
+{
+ return tg;
+}
+
+#ifdef CONFIG_SCHED_DEBUG
+static inline int autogroup_path(struct task_group *tg, char *buf, int buflen)
+{
+ return 0;
+}
+#endif
+
+#endif /* CONFIG_SCHED_AUTOGROUP */
diff --git a/kernel/sched_clock.c b/kernel/sched_clock.c
index 52f1a149bfb..9d8af0b3fb6 100644
--- a/kernel/sched_clock.c
+++ b/kernel/sched_clock.c
@@ -79,7 +79,7 @@ unsigned long long __attribute__((weak)) sched_clock(void)
}
EXPORT_SYMBOL_GPL(sched_clock);
-static __read_mostly int sched_clock_running;
+__read_mostly int sched_clock_running;
#ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
__read_mostly int sched_clock_stable;
diff --git a/kernel/sched_debug.c b/kernel/sched_debug.c
index 2e1b0d17dd9..1dfae3d014b 100644
--- a/kernel/sched_debug.c
+++ b/kernel/sched_debug.c
@@ -54,8 +54,7 @@ static unsigned long nsec_low(unsigned long long nsec)
#define SPLIT_NS(x) nsec_high(x), nsec_low(x)
#ifdef CONFIG_FAIR_GROUP_SCHED
-static void print_cfs_group_stats(struct seq_file *m, int cpu,
- struct task_group *tg)
+static void print_cfs_group_stats(struct seq_file *m, int cpu, struct task_group *tg)
{
struct sched_entity *se = tg->se[cpu];
if (!se)
@@ -110,16 +109,6 @@ print_task(struct seq_file *m, struct rq *rq, struct task_struct *p)
0LL, 0LL, 0LL, 0L, 0LL, 0L, 0LL, 0L);
#endif
-#ifdef CONFIG_CGROUP_SCHED
- {
- char path[64];
-
- rcu_read_lock();
- cgroup_path(task_group(p)->css.cgroup, path, sizeof(path));
- rcu_read_unlock();
- SEQ_printf(m, " %s", path);
- }
-#endif
SEQ_printf(m, "\n");
}
@@ -147,19 +136,6 @@ static void print_rq(struct seq_file *m, struct rq *rq, int rq_cpu)
read_unlock_irqrestore(&tasklist_lock, flags);
}
-#if defined(CONFIG_CGROUP_SCHED) && \
- (defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED))
-static void task_group_path(struct task_group *tg, char *buf, int buflen)
-{
- /* may be NULL if the underlying cgroup isn't fully-created yet */
- if (!tg->css.cgroup) {
- buf[0] = '\0';
- return;
- }
- cgroup_path(tg->css.cgroup, buf, buflen);
-}
-#endif
-
void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
{
s64 MIN_vruntime = -1, min_vruntime, max_vruntime = -1,
@@ -168,16 +144,7 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
struct sched_entity *last;
unsigned long flags;
-#if defined(CONFIG_CGROUP_SCHED) && defined(CONFIG_FAIR_GROUP_SCHED)
- char path[128];
- struct task_group *tg = cfs_rq->tg;
-
- task_group_path(tg, path, sizeof(path));
-
- SEQ_printf(m, "\ncfs_rq[%d]:%s\n", cpu, path);
-#else
SEQ_printf(m, "\ncfs_rq[%d]:\n", cpu);
-#endif
SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "exec_clock",
SPLIT_NS(cfs_rq->exec_clock));
@@ -202,32 +169,29 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
spread0 = min_vruntime - rq0_min_vruntime;
SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "spread0",
SPLIT_NS(spread0));
- SEQ_printf(m, " .%-30s: %ld\n", "nr_running", cfs_rq->nr_running);
- SEQ_printf(m, " .%-30s: %ld\n", "load", cfs_rq->load.weight);
-
SEQ_printf(m, " .%-30s: %d\n", "nr_spread_over",
cfs_rq->nr_spread_over);
+ SEQ_printf(m, " .%-30s: %ld\n", "nr_running", cfs_rq->nr_running);
+ SEQ_printf(m, " .%-30s: %ld\n", "load", cfs_rq->load.weight);
#ifdef CONFIG_FAIR_GROUP_SCHED
#ifdef CONFIG_SMP
- SEQ_printf(m, " .%-30s: %lu\n", "shares", cfs_rq->shares);
+ SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "load_avg",
+ SPLIT_NS(cfs_rq->load_avg));
+ SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "load_period",
+ SPLIT_NS(cfs_rq->load_period));
+ SEQ_printf(m, " .%-30s: %ld\n", "load_contrib",
+ cfs_rq->load_contribution);
+ SEQ_printf(m, " .%-30s: %d\n", "load_tg",
+ atomic_read(&cfs_rq->tg->load_weight));
#endif
+
print_cfs_group_stats(m, cpu, cfs_rq->tg);
#endif
}
void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq)
{
-#if defined(CONFIG_CGROUP_SCHED) && defined(CONFIG_RT_GROUP_SCHED)
- char path[128];
- struct task_group *tg = rt_rq->tg;
-
- task_group_path(tg, path, sizeof(path));
-
- SEQ_printf(m, "\nrt_rq[%d]:%s\n", cpu, path);
-#else
SEQ_printf(m, "\nrt_rq[%d]:\n", cpu);
-#endif
-
#define P(x) \
SEQ_printf(m, " .%-30s: %Ld\n", #x, (long long)(rt_rq->x))
@@ -243,6 +207,8 @@ void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq)
#undef P
}
+extern __read_mostly int sched_clock_running;
+
static void print_cpu(struct seq_file *m, int cpu)
{
struct rq *rq = cpu_rq(cpu);
@@ -314,21 +280,42 @@ static const char *sched_tunable_scaling_names[] = {
static int sched_debug_show(struct seq_file *m, void *v)
{
- u64 now = ktime_to_ns(ktime_get());
+ u64 ktime, sched_clk, cpu_clk;
+ unsigned long flags;
int cpu;
- SEQ_printf(m, "Sched Debug Version: v0.09, %s %.*s\n",
+ local_irq_save(flags);
+ ktime = ktime_to_ns(ktime_get());
+ sched_clk = sched_clock();
+ cpu_clk = local_clock();
+ local_irq_restore(flags);
+
+ SEQ_printf(m, "Sched Debug Version: v0.10, %s %.*s\n",
init_utsname()->release,
(int)strcspn(init_utsname()->version, " "),
init_utsname()->version);
- SEQ_printf(m, "now at %Lu.%06ld msecs\n", SPLIT_NS(now));
+#define P(x) \
+ SEQ_printf(m, "%-40s: %Ld\n", #x, (long long)(x))
+#define PN(x) \
+ SEQ_printf(m, "%-40s: %Ld.%06ld\n", #x, SPLIT_NS(x))
+ PN(ktime);
+ PN(sched_clk);
+ PN(cpu_clk);
+ P(jiffies);
+#ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
+ P(sched_clock_stable);
+#endif
+#undef PN
+#undef P
+
+ SEQ_printf(m, "\n");
+ SEQ_printf(m, "sysctl_sched\n");
#define P(x) \
SEQ_printf(m, " .%-40s: %Ld\n", #x, (long long)(x))
#define PN(x) \
SEQ_printf(m, " .%-40s: %Ld.%06ld\n", #x, SPLIT_NS(x))
- P(jiffies);
PN(sysctl_sched_latency);
PN(sysctl_sched_min_granularity);
PN(sysctl_sched_wakeup_granularity);
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 00ebd768667..c62ebae65cf 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -89,6 +89,13 @@ unsigned int normalized_sysctl_sched_wakeup_granularity = 1000000UL;
const_debug unsigned int sysctl_sched_migration_cost = 500000UL;
+/*
+ * The exponential sliding window over which load is averaged for shares
+ * distribution.
+ * (default: 10msec)
+ */
+unsigned int __read_mostly sysctl_sched_shares_window = 10000000UL;
+
static const struct sched_class fair_sched_class;
/**************************************************************
@@ -143,6 +150,36 @@ static inline struct cfs_rq *cpu_cfs_rq(struct cfs_rq *cfs_rq, int this_cpu)
return cfs_rq->tg->cfs_rq[this_cpu];
}
+static inline void list_add_leaf_cfs_rq(struct cfs_rq *cfs_rq)
+{
+ if (!cfs_rq->on_list) {
+ /*
+ * Ensure we either appear before our parent (if already
+ * enqueued) or force our parent to appear after us when it is
+ * enqueued. The fact that we always enqueue bottom-up
+ * reduces this to two cases.
+ */
+ if (cfs_rq->tg->parent &&
+ cfs_rq->tg->parent->cfs_rq[cpu_of(rq_of(cfs_rq))]->on_list) {
+ list_add_rcu(&cfs_rq->leaf_cfs_rq_list,
+ &rq_of(cfs_rq)->leaf_cfs_rq_list);
+ } else {
+ list_add_tail_rcu(&cfs_rq->leaf_cfs_rq_list,
+ &rq_of(cfs_rq)->leaf_cfs_rq_list);
+ }
+
+ cfs_rq->on_list = 1;
+ }
+}
+
+static inline void list_del_leaf_cfs_rq(struct cfs_rq *cfs_rq)
+{
+ if (cfs_rq->on_list) {
+ list_del_rcu(&cfs_rq->leaf_cfs_rq_list);
+ cfs_rq->on_list = 0;
+ }
+}
+
/* Iterate thr' all leaf cfs_rq's on a runqueue */
#define for_each_leaf_cfs_rq(rq, cfs_rq) \
list_for_each_entry_rcu(cfs_rq, &rq->leaf_cfs_rq_list, leaf_cfs_rq_list)
@@ -246,6 +283,14 @@ static inline struct cfs_rq *cpu_cfs_rq(struct cfs_rq *cfs_rq, int this_cpu)
return &cpu_rq(this_cpu)->cfs;
}
+static inline void list_add_leaf_cfs_rq(struct cfs_rq *cfs_rq)
+{
+}
+
+static inline void list_del_leaf_cfs_rq(struct cfs_rq *cfs_rq)
+{
+}
+
#define for_each_leaf_cfs_rq(rq, cfs_rq) \
for (cfs_rq = &rq->cfs; cfs_rq; cfs_rq = NULL)
@@ -417,7 +462,6 @@ int sched_proc_update_handler(struct ctl_table *table, int write,
WRT_SYSCTL(sched_min_granularity);
WRT_SYSCTL(sched_latency);
WRT_SYSCTL(sched_wakeup_granularity);
- WRT_SYSCTL(sched_shares_ratelimit);
#undef WRT_SYSCTL
return 0;
@@ -495,6 +539,9 @@ static u64 sched_vslice(struct cfs_rq *cfs_rq, struct sched_entity *se)
return calc_delta_fair(sched_slice(cfs_rq, se), se);
}
+static void update_cfs_load(struct cfs_rq *cfs_rq, int global_update);
+static void update_cfs_shares(struct cfs_rq *cfs_rq, long weight_delta);
+
/*
* Update the current task's runtime statistics. Skip current tasks that
* are not in our scheduling class.
@@ -514,6 +561,10 @@ __update_curr(struct cfs_rq *cfs_rq, struct sched_entity *curr,
curr->vruntime += delta_exec_weighted;
update_min_vruntime(cfs_rq);
+
+#if defined CONFIG_SMP && defined CONFIG_FAIR_GROUP_SCHED
+ cfs_rq->load_unacc_exec_time += delta_exec;
+#endif
}
static void update_curr(struct cfs_rq *cfs_rq)
@@ -633,7 +684,6 @@ account_entity_enqueue(struct cfs_rq *cfs_rq, struct sched_entity *se)
list_add(&se->group_node, &cfs_rq->tasks);
}
cfs_rq->nr_running++;
- se->on_rq = 1;
}
static void
@@ -647,9 +697,140 @@ account_entity_dequeue(struct cfs_rq *cfs_rq, struct sched_entity *se)
list_del_init(&se->group_node);
}
cfs_rq->nr_running--;
- se->on_rq = 0;
}
+#if defined CONFIG_SMP && defined CONFIG_FAIR_GROUP_SCHED
+static void update_cfs_rq_load_contribution(struct cfs_rq *cfs_rq,
+ int global_update)
+{
+ struct task_group *tg = cfs_rq->tg;
+ long load_avg;
+
+ load_avg = div64_u64(cfs_rq->load_avg, cfs_rq->load_period+1);
+ load_avg -= cfs_rq->load_contribution;
+
+ if (global_update || abs(load_avg) > cfs_rq->load_contribution / 8) {
+ atomic_add(load_avg, &tg->load_weight);
+ cfs_rq->load_contribution += load_avg;
+ }
+}
+
+static void update_cfs_load(struct cfs_rq *cfs_rq, int global_update)
+{
+ u64 period = sysctl_sched_shares_window;
+ u64 now, delta;
+ unsigned long load = cfs_rq->load.weight;
+
+ if (!cfs_rq)
+ return;
+
+ now = rq_of(cfs_rq)->clock;
+ delta = now - cfs_rq->load_stamp;
+
+ /* truncate load history at 4 idle periods */
+ if (cfs_rq->load_stamp > cfs_rq->load_last &&
+ now - cfs_rq->load_last > 4 * period) {
+ cfs_rq->load_period = 0;
+ cfs_rq->load_avg = 0;
+ }
+
+ cfs_rq->load_stamp = now;
+ cfs_rq->load_unacc_exec_time = 0;
+ cfs_rq->load_period += delta;
+ if (load) {
+ cfs_rq->load_last = now;
+ cfs_rq->load_avg += delta * load;
+ }
+
+ /* consider updating load contribution on each fold or truncate */
+ if (global_update || cfs_rq->load_period > period
+ || !cfs_rq->load_period)
+ update_cfs_rq_load_contribution(cfs_rq, global_update);
+
+ while (cfs_rq->load_period > period) {
+ /*
+ * Inline assembly required to prevent the compiler
+ * optimising this loop into a divmod call.
+ * See __iter_div_u64_rem() for another example of this.
+ */
+ asm("" : "+rm" (cfs_rq->load_period));
+ cfs_rq->load_period /= 2;
+ cfs_rq->load_avg /= 2;
+ }
+
+ if (!cfs_rq->curr && !cfs_rq->nr_running && !cfs_rq->load_avg)
+ list_del_leaf_cfs_rq(cfs_rq);
+}
+
+static void reweight_entity(struct cfs_rq *cfs_rq, struct sched_entity *se,
+ unsigned long weight)
+{
+ if (se->on_rq) {
+ /* commit outstanding execution time */
+ if (cfs_rq->curr == se)
+ update_curr(cfs_rq);
+ account_entity_dequeue(cfs_rq, se);
+ }
+
+ update_load_set(&se->load, weight);
+
+ if (se->on_rq)
+ account_entity_enqueue(cfs_rq, se);
+}
+
+static void update_cfs_shares(struct cfs_rq *cfs_rq, long weight_delta)
+{
+ struct task_group *tg;
+ struct sched_entity *se;
+ long load_weight, load, shares;
+
+ if (!cfs_rq)
+ return;
+
+ tg = cfs_rq->tg;
+ se = tg->se[cpu_of(rq_of(cfs_rq))];
+ if (!se)
+ return;
+
+ load = cfs_rq->load.weight + weight_delta;
+
+ load_weight = atomic_read(&tg->load_weight);
+ load_weight -= cfs_rq->load_contribution;
+ load_weight += load;
+
+ shares = (tg->shares * load);
+ if (load_weight)
+ shares /= load_weight;
+
+ if (shares < MIN_SHARES)
+ shares = MIN_SHARES;
+ if (shares > tg->shares)
+ shares = tg->shares;
+
+ reweight_entity(cfs_rq_of(se), se, shares);
+}
+
+static void update_entity_shares_tick(struct cfs_rq *cfs_rq)
+{
+ if (cfs_rq->load_unacc_exec_time > sysctl_sched_shares_window) {
+ update_cfs_load(cfs_rq, 0);
+ update_cfs_shares(cfs_rq, 0);
+ }
+}
+#else /* CONFIG_FAIR_GROUP_SCHED */
+static void update_cfs_load(struct cfs_rq *cfs_rq, int global_update)
+{
+}
+
+static inline void update_cfs_shares(struct cfs_rq *cfs_rq, long weight_delta)
+{
+}
+
+static inline void update_entity_shares_tick(struct cfs_rq *cfs_rq)
+{
+}
+#endif /* CONFIG_FAIR_GROUP_SCHED */
+
static void enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
#ifdef CONFIG_SCHEDSTATS
@@ -771,6 +952,8 @@ enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags)
* Update run-time statistics of the 'current'.
*/
update_curr(cfs_rq);
+ update_cfs_load(cfs_rq, 0);
+ update_cfs_shares(cfs_rq, se->load.weight);
account_entity_enqueue(cfs_rq, se);
if (flags & ENQUEUE_WAKEUP) {
@@ -782,6 +965,10 @@ enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags)
check_spread(cfs_rq, se);
if (se != cfs_rq->curr)
__enqueue_entity(cfs_rq, se);
+ se->on_rq = 1;
+
+ if (cfs_rq->nr_running == 1)
+ list_add_leaf_cfs_rq(cfs_rq);
}
static void __clear_buddies(struct cfs_rq *cfs_rq, struct sched_entity *se)
@@ -825,8 +1012,11 @@ dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags)
if (se != cfs_rq->curr)
__dequeue_entity(cfs_rq, se);
+ se->on_rq = 0;
+ update_cfs_load(cfs_rq, 0);
account_entity_dequeue(cfs_rq, se);
update_min_vruntime(cfs_rq);
+ update_cfs_shares(cfs_rq, 0);
/*
* Normalize the entity after updating the min_vruntime because the
@@ -955,6 +1145,11 @@ entity_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr, int queued)
*/
update_curr(cfs_rq);
+ /*
+ * Update share accounting for long-running entities.
+ */
+ update_entity_shares_tick(cfs_rq);
+
#ifdef CONFIG_SCHED_HRTICK
/*
* queued ticks are scheduled to match the slice, so don't bother
@@ -1055,6 +1250,13 @@ enqueue_task_fair(struct rq *rq, struct task_struct *p, int flags)
flags = ENQUEUE_WAKEUP;
}
+ for_each_sched_entity(se) {
+ struct cfs_rq *cfs_rq = cfs_rq_of(se);
+
+ update_cfs_load(cfs_rq, 0);
+ update_cfs_shares(cfs_rq, 0);
+ }
+
hrtick_update(rq);
}
@@ -1071,12 +1273,20 @@ static void dequeue_task_fair(struct rq *rq, struct task_struct *p, int flags)
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)
break;
flags |= DEQUEUE_SLEEP;
}
+ for_each_sched_entity(se) {
+ struct cfs_rq *cfs_rq = cfs_rq_of(se);
+
+ update_cfs_load(cfs_rq, 0);
+ update_cfs_shares(cfs_rq, 0);
+ }
+
hrtick_update(rq);
}
@@ -1143,51 +1353,20 @@ static void task_waking_fair(struct rq *rq, struct task_struct *p)
* Adding load to a group doesn't make a group heavier, but can cause movement
* of group shares between cpus. Assuming the shares were perfectly aligned one
* can calculate the shift in shares.
- *
- * The problem is that perfectly aligning the shares is rather expensive, hence
- * we try to avoid doing that too often - see update_shares(), which ratelimits
- * this change.
- *
- * We compensate this by not only taking the current delta into account, but
- * also considering the delta between when the shares were last adjusted and
- * now.
- *
- * We still saw a performance dip, some tracing learned us that between
- * cgroup:/ and cgroup:/foo balancing the number of affine wakeups increased
- * significantly. Therefore try to bias the error in direction of failing
- * the affine wakeup.
- *
*/
-static long effective_load(struct task_group *tg, int cpu,
- long wl, long wg)
+static long effective_load(struct task_group *tg, int cpu, long wl, long wg)
{
struct sched_entity *se = tg->se[cpu];
if (!tg->parent)
return wl;
- /*
- * By not taking the decrease of shares on the other cpu into
- * account our error leans towards reducing the affine wakeups.
- */
- if (!wl && sched_feat(ASYM_EFF_LOAD))
- return wl;
-
for_each_sched_entity(se) {
long S, rw, s, a, b;
- long more_w;
-
- /*
- * Instead of using this increment, also add the difference
- * between when the shares were last updated and now.
- */
- more_w = se->my_q->load.weight - se->my_q->rq_weight;
- wl += more_w;
- wg += more_w;
S = se->my_q->tg->shares;
- s = se->my_q->shares;
- rw = se->my_q->rq_weight;
+ s = se->load.weight;
+ rw = se->my_q->load.weight;
a = S*(rw + wl);
b = S*rw + s*wg;
@@ -1508,23 +1687,6 @@ select_task_rq_fair(struct rq *rq, struct task_struct *p, int sd_flag, int wake_
sd = tmp;
}
-#ifdef CONFIG_FAIR_GROUP_SCHED
- if (sched_feat(LB_SHARES_UPDATE)) {
- /*
- * Pick the largest domain to update shares over
- */
- tmp = sd;
- if (affine_sd && (!tmp || affine_sd->span_weight > sd->span_weight))
- tmp = affine_sd;
-
- if (tmp) {
- raw_spin_unlock(&rq->lock);
- update_shares(tmp);
- raw_spin_lock(&rq->lock);
- }
- }
-#endif
-
if (affine_sd) {
if (cpu == prev_cpu || wake_affine(affine_sd, p, sync))
return select_idle_sibling(p, cpu);
@@ -1909,6 +2071,48 @@ out:
}
#ifdef CONFIG_FAIR_GROUP_SCHED
+/*
+ * update tg->load_weight by folding this cpu's load_avg
+ */
+static int update_shares_cpu(struct task_group *tg, int cpu)
+{
+ struct cfs_rq *cfs_rq;
+ unsigned long flags;
+ struct rq *rq;
+
+ if (!tg->se[cpu])
+ return 0;
+
+ rq = cpu_rq(cpu);
+ cfs_rq = tg->cfs_rq[cpu];
+
+ raw_spin_lock_irqsave(&rq->lock, flags);
+
+ update_rq_clock(rq);
+ update_cfs_load(cfs_rq, 1);
+
+ /*
+ * We need to update shares after updating tg->load_weight in
+ * order to adjust the weight of groups with long running tasks.
+ */
+ update_cfs_shares(cfs_rq, 0);
+
+ raw_spin_unlock_irqrestore(&rq->lock, flags);
+
+ return 0;
+}
+
+static void update_shares(int cpu)
+{
+ struct cfs_rq *cfs_rq;
+ struct rq *rq = cpu_rq(cpu);
+
+ rcu_read_lock();
+ for_each_leaf_cfs_rq(rq, cfs_rq)
+ update_shares_cpu(cfs_rq->tg, cpu);
+ rcu_read_unlock();
+}
+
static unsigned long
load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
unsigned long max_load_move,
@@ -1956,6 +2160,10 @@ load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
return max_load_move - rem_load_move;
}
#else
+static inline void update_shares(int cpu)
+{
+}
+
static unsigned long
load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
unsigned long max_load_move,
@@ -3032,7 +3240,6 @@ static int load_balance(int this_cpu, struct rq *this_rq,
schedstat_inc(sd, lb_count[idle]);
redo:
- update_shares(sd);
group = find_busiest_group(sd, this_cpu, &imbalance, idle, &sd_idle,
cpus, balance);
@@ -3174,8 +3381,6 @@ out_one_pinned:
else
ld_moved = 0;
out:
- if (ld_moved)
- update_shares(sd);
return ld_moved;
}
@@ -3199,6 +3404,7 @@ static void idle_balance(int this_cpu, struct rq *this_rq)
*/
raw_spin_unlock(&this_rq->lock);
+ update_shares(this_cpu);
for_each_domain(this_cpu, sd) {
unsigned long interval;
int balance = 1;
@@ -3569,6 +3775,8 @@ static void rebalance_domains(int cpu, enum cpu_idle_type idle)
int update_next_balance = 0;
int need_serialize;
+ update_shares(cpu);
+
for_each_domain(cpu, sd) {
if (!(sd->flags & SD_LOAD_BALANCE))
continue;
diff --git a/kernel/sched_features.h b/kernel/sched_features.h
index 185f920ec1a..68e69acc29b 100644
--- a/kernel/sched_features.h
+++ b/kernel/sched_features.h
@@ -52,8 +52,6 @@ SCHED_FEAT(ARCH_POWER, 0)
SCHED_FEAT(HRTICK, 0)
SCHED_FEAT(DOUBLE_TICK, 0)
SCHED_FEAT(LB_BIAS, 1)
-SCHED_FEAT(LB_SHARES_UPDATE, 1)
-SCHED_FEAT(ASYM_EFF_LOAD, 1)
/*
* Spin-wait on mutex acquisition when the mutex owner is running on
diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c
index bea7d79f7e9..c914ec747ca 100644
--- a/kernel/sched_rt.c
+++ b/kernel/sched_rt.c
@@ -183,6 +183,17 @@ static inline u64 sched_rt_period(struct rt_rq *rt_rq)
return ktime_to_ns(rt_rq->tg->rt_bandwidth.rt_period);
}
+static inline void list_add_leaf_rt_rq(struct rt_rq *rt_rq)
+{
+ list_add_rcu(&rt_rq->leaf_rt_rq_list,
+ &rq_of_rt_rq(rt_rq)->leaf_rt_rq_list);
+}
+
+static inline void list_del_leaf_rt_rq(struct rt_rq *rt_rq)
+{
+ list_del_rcu(&rt_rq->leaf_rt_rq_list);
+}
+
#define for_each_leaf_rt_rq(rt_rq, rq) \
list_for_each_entry_rcu(rt_rq, &rq->leaf_rt_rq_list, leaf_rt_rq_list)
@@ -276,6 +287,14 @@ static inline u64 sched_rt_period(struct rt_rq *rt_rq)
return ktime_to_ns(def_rt_bandwidth.rt_period);
}
+static inline void list_add_leaf_rt_rq(struct rt_rq *rt_rq)
+{
+}
+
+static inline void list_del_leaf_rt_rq(struct rt_rq *rt_rq)
+{
+}
+
#define for_each_leaf_rt_rq(rt_rq, rq) \
for (rt_rq = &rq->rt; rt_rq; rt_rq = NULL)
@@ -825,6 +844,9 @@ static void __enqueue_rt_entity(struct sched_rt_entity *rt_se, bool head)
if (group_rq && (rt_rq_throttled(group_rq) || !group_rq->rt_nr_running))
return;
+ if (!rt_rq->rt_nr_running)
+ list_add_leaf_rt_rq(rt_rq);
+
if (head)
list_add(&rt_se->run_list, queue);
else
@@ -844,6 +866,8 @@ static void __dequeue_rt_entity(struct sched_rt_entity *rt_se)
__clear_bit(rt_se_prio(rt_se), array->bitmap);
dec_rt_tasks(rt_se, rt_rq);
+ if (!rt_rq->rt_nr_running)
+ list_del_leaf_rt_rq(rt_rq);
}
/*
diff --git a/kernel/softirq.c b/kernel/softirq.c
index 18f4be0d5fe..d4d918a9188 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -853,7 +853,9 @@ static int __cpuinit cpu_callback(struct notifier_block *nfb,
cpumask_any(cpu_online_mask));
case CPU_DEAD:
case CPU_DEAD_FROZEN: {
- struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 };
+ static struct sched_param param = {
+ .sched_priority = MAX_RT_PRIO-1
+ };
p = per_cpu(ksoftirqd, hotcpu);
per_cpu(ksoftirqd, hotcpu) = NULL;
diff --git a/kernel/sys.c b/kernel/sys.c
index 7f5a0cd296a..2745dcdb6c6 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -1080,8 +1080,10 @@ SYSCALL_DEFINE0(setsid)
err = session;
out:
write_unlock_irq(&tasklist_lock);
- if (err > 0)
+ if (err > 0) {
proc_sid_connector(group_leader);
+ sched_autogroup_create_attach(group_leader);
+ }
return err;
}
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 46404414d8a..ae5cbb1e3ce 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -259,8 +259,6 @@ static int min_wakeup_granularity_ns; /* 0 usecs */
static int max_wakeup_granularity_ns = NSEC_PER_SEC; /* 1 second */
static int min_sched_tunable_scaling = SCHED_TUNABLESCALING_NONE;
static int max_sched_tunable_scaling = SCHED_TUNABLESCALING_END-1;
-static int min_sched_shares_ratelimit = 100000; /* 100 usec */
-static int max_sched_shares_ratelimit = NSEC_PER_SEC; /* 1 second */
#endif
#ifdef CONFIG_COMPACTION
@@ -305,15 +303,6 @@ static struct ctl_table kern_table[] = {
.extra2 = &max_wakeup_granularity_ns,
},
{
- .procname = "sched_shares_ratelimit",
- .data = &sysctl_sched_shares_ratelimit,
- .maxlen = sizeof(unsigned int),
- .mode = 0644,
- .proc_handler = sched_proc_update_handler,
- .extra1 = &min_sched_shares_ratelimit,
- .extra2 = &max_sched_shares_ratelimit,
- },
- {
.procname = "sched_tunable_scaling",
.data = &sysctl_sched_tunable_scaling,
.maxlen = sizeof(enum sched_tunable_scaling),
@@ -323,14 +312,6 @@ static struct ctl_table kern_table[] = {
.extra2 = &max_sched_tunable_scaling,
},
{
- .procname = "sched_shares_thresh",
- .data = &sysctl_sched_shares_thresh,
- .maxlen = sizeof(unsigned int),
- .mode = 0644,
- .proc_handler = proc_dointvec_minmax,
- .extra1 = &zero,
- },
- {
.procname = "sched_migration_cost",
.data = &sysctl_sched_migration_cost,
.maxlen = sizeof(unsigned int),
@@ -352,6 +333,13 @@ static struct ctl_table kern_table[] = {
.proc_handler = proc_dointvec,
},
{
+ .procname = "sched_shares_window",
+ .data = &sysctl_sched_shares_window,
+ .maxlen = sizeof(unsigned int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec,
+ },
+ {
.procname = "timer_migration",
.data = &sysctl_timer_migration,
.maxlen = sizeof(unsigned int),
@@ -382,6 +370,17 @@ static struct ctl_table kern_table[] = {
.mode = 0644,
.proc_handler = proc_dointvec,
},
+#ifdef CONFIG_SCHED_AUTOGROUP
+ {
+ .procname = "sched_autogroup_enabled",
+ .data = &sysctl_sched_autogroup_enabled,
+ .maxlen = sizeof(unsigned int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec,
+ .extra1 = &zero,
+ .extra2 = &one,
+ },
+#endif
#ifdef CONFIG_PROVE_LOCKING
{
.procname = "prove_locking",
diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index 155a415b320..562c56e048f 100644
--- a/kernel/trace/trace_selftest.c
+++ b/kernel/trace/trace_selftest.c
@@ -558,7 +558,7 @@ trace_selftest_startup_nop(struct tracer *trace, struct trace_array *tr)
static int trace_wakeup_test_thread(void *data)
{
/* Make this a RT thread, doesn't need to be too high */
- struct sched_param param = { .sched_priority = 5 };
+ static struct sched_param param = { .sched_priority = 5 };
struct completion *x = data;
sched_setscheduler(current, SCHED_FIFO, &param);
diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index aaa8dae0823..6e7b575ac33 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -309,7 +309,7 @@ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer)
*/
static int watchdog(void *unused)
{
- struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 };
+ static struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 };
struct hrtimer *hrtimer = &__raw_get_cpu_var(watchdog_hrtimer);
sched_setscheduler(current, SCHED_FIFO, &param);