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authorLinus Torvalds <torvalds@linux-foundation.org>2013-02-24 16:06:13 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2013-02-24 16:18:31 -0800
commit77be36de8b07027a70fbc8f02703ccd76cd16d09 (patch)
treee2310718e39cb0dcfe93942d4c990df9154a7ecd /drivers/xen/events.c
parent89f883372fa60f604d136924baf3e89ff1870e9e (diff)
parentc81611c4e96f595a80d8be9367c385d2c116428b (diff)
Merge tag 'stable/for-linus-3.9-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
Pull Xen update from Konrad Rzeszutek Wilk: "This has two new ACPI drivers for Xen - a physical CPU offline/online and a memory hotplug. The way this works is that ACPI kicks the drivers and they make the appropiate hypercall to the hypervisor to tell it that there is a new CPU or memory. There also some changes to the Xen ARM ABIs and couple of fixes. One particularly nasty bug in the Xen PV spinlock code was fixed by Stefan Bader - and has been there since the 2.6.32! Features: - Xen ACPI memory and CPU hotplug drivers - allowing Xen hypervisor to be aware of new CPU and new DIMMs - Cleanups Bug-fixes: - Fixes a long-standing bug in the PV spinlock wherein we did not kick VCPUs that were in a tight loop. - Fixes in the error paths for the event channel machinery" Fix up a few semantic conflicts with the ACPI interface changes in drivers/xen/xen-acpi-{cpu,mem}hotplug.c. * tag 'stable/for-linus-3.9-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen: event channel arrays are xen_ulong_t and not unsigned long xen: Send spinlock IPI to all waiters xen: introduce xen_remap, use it instead of ioremap xen: close evtchn port if binding to irq fails xen-evtchn: correct comment and error output xen/tmem: Add missing %s in the printk statement. xen/acpi: move xen_acpi_get_pxm under CONFIG_XEN_DOM0 xen/acpi: ACPI cpu hotplug xen/acpi: Move xen_acpi_get_pxm to Xen's acpi.h xen/stub: driver for CPU hotplug xen/acpi: ACPI memory hotplug xen/stub: driver for memory hotplug xen: implement updated XENMEM_add_to_physmap_range ABI xen/smp: Move the common CPU init code a bit to prep for PVH patch.
Diffstat (limited to 'drivers/xen/events.c')
-rw-r--r--drivers/xen/events.c115
1 files changed, 67 insertions, 48 deletions
diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index 22f77c5f601..d17aa41a904 100644
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -120,7 +120,22 @@ static unsigned long *pirq_eoi_map;
#endif
static bool (*pirq_needs_eoi)(unsigned irq);
-static DEFINE_PER_CPU(unsigned long [NR_EVENT_CHANNELS/BITS_PER_LONG],
+/*
+ * Note sizeof(xen_ulong_t) can be more than sizeof(unsigned long). Be
+ * careful to only use bitops which allow for this (e.g
+ * test_bit/find_first_bit and friends but not __ffs) and to pass
+ * BITS_PER_EVTCHN_WORD as the bitmask length.
+ */
+#define BITS_PER_EVTCHN_WORD (sizeof(xen_ulong_t)*8)
+/*
+ * Make a bitmask (i.e. unsigned long *) of a xen_ulong_t
+ * array. Primarily to avoid long lines (hence the terse name).
+ */
+#define BM(x) (unsigned long *)(x)
+/* Find the first set bit in a evtchn mask */
+#define EVTCHN_FIRST_BIT(w) find_first_bit(BM(&(w)), BITS_PER_EVTCHN_WORD)
+
+static DEFINE_PER_CPU(xen_ulong_t [NR_EVENT_CHANNELS/BITS_PER_EVTCHN_WORD],
cpu_evtchn_mask);
/* Xen will never allocate port zero for any purpose. */
@@ -294,9 +309,9 @@ static bool pirq_needs_eoi_flag(unsigned irq)
return info->u.pirq.flags & PIRQ_NEEDS_EOI;
}
-static inline unsigned long active_evtchns(unsigned int cpu,
- struct shared_info *sh,
- unsigned int idx)
+static inline xen_ulong_t active_evtchns(unsigned int cpu,
+ struct shared_info *sh,
+ unsigned int idx)
{
return sh->evtchn_pending[idx] &
per_cpu(cpu_evtchn_mask, cpu)[idx] &
@@ -312,8 +327,8 @@ static void bind_evtchn_to_cpu(unsigned int chn, unsigned int cpu)
cpumask_copy(irq_to_desc(irq)->irq_data.affinity, cpumask_of(cpu));
#endif
- clear_bit(chn, per_cpu(cpu_evtchn_mask, cpu_from_irq(irq)));
- set_bit(chn, per_cpu(cpu_evtchn_mask, cpu));
+ clear_bit(chn, BM(per_cpu(cpu_evtchn_mask, cpu_from_irq(irq))));
+ set_bit(chn, BM(per_cpu(cpu_evtchn_mask, cpu)));
info_for_irq(irq)->cpu = cpu;
}
@@ -339,19 +354,19 @@ static void init_evtchn_cpu_bindings(void)
static inline void clear_evtchn(int port)
{
struct shared_info *s = HYPERVISOR_shared_info;
- sync_clear_bit(port, &s->evtchn_pending[0]);
+ sync_clear_bit(port, BM(&s->evtchn_pending[0]));
}
static inline void set_evtchn(int port)
{
struct shared_info *s = HYPERVISOR_shared_info;
- sync_set_bit(port, &s->evtchn_pending[0]);
+ sync_set_bit(port, BM(&s->evtchn_pending[0]));
}
static inline int test_evtchn(int port)
{
struct shared_info *s = HYPERVISOR_shared_info;
- return sync_test_bit(port, &s->evtchn_pending[0]);
+ return sync_test_bit(port, BM(&s->evtchn_pending[0]));
}
@@ -375,7 +390,7 @@ EXPORT_SYMBOL_GPL(notify_remote_via_irq);
static void mask_evtchn(int port)
{
struct shared_info *s = HYPERVISOR_shared_info;
- sync_set_bit(port, &s->evtchn_mask[0]);
+ sync_set_bit(port, BM(&s->evtchn_mask[0]));
}
static void unmask_evtchn(int port)
@@ -389,7 +404,7 @@ static void unmask_evtchn(int port)
if (unlikely((cpu != cpu_from_evtchn(port))))
do_hypercall = 1;
else
- evtchn_pending = sync_test_bit(port, &s->evtchn_pending[0]);
+ evtchn_pending = sync_test_bit(port, BM(&s->evtchn_pending[0]));
if (unlikely(evtchn_pending && xen_hvm_domain()))
do_hypercall = 1;
@@ -403,7 +418,7 @@ static void unmask_evtchn(int port)
} else {
struct vcpu_info *vcpu_info = __this_cpu_read(xen_vcpu);
- sync_clear_bit(port, &s->evtchn_mask[0]);
+ sync_clear_bit(port, BM(&s->evtchn_mask[0]));
/*
* The following is basically the equivalent of
@@ -411,8 +426,8 @@ static void unmask_evtchn(int port)
* the interrupt edge' if the channel is masked.
*/
if (evtchn_pending &&
- !sync_test_and_set_bit(port / BITS_PER_LONG,
- &vcpu_info->evtchn_pending_sel))
+ !sync_test_and_set_bit(port / BITS_PER_EVTCHN_WORD,
+ BM(&vcpu_info->evtchn_pending_sel)))
vcpu_info->evtchn_upcall_pending = 1;
}
@@ -1189,7 +1204,7 @@ irqreturn_t xen_debug_interrupt(int irq, void *dev_id)
{
struct shared_info *sh = HYPERVISOR_shared_info;
int cpu = smp_processor_id();
- unsigned long *cpu_evtchn = per_cpu(cpu_evtchn_mask, cpu);
+ xen_ulong_t *cpu_evtchn = per_cpu(cpu_evtchn_mask, cpu);
int i;
unsigned long flags;
static DEFINE_SPINLOCK(debug_lock);
@@ -1205,7 +1220,7 @@ irqreturn_t xen_debug_interrupt(int irq, void *dev_id)
pending = (get_irq_regs() && i == cpu)
? xen_irqs_disabled(get_irq_regs())
: v->evtchn_upcall_mask;
- printk("%d: masked=%d pending=%d event_sel %0*lx\n ", i,
+ printk("%d: masked=%d pending=%d event_sel %0*"PRI_xen_ulong"\n ", i,
pending, v->evtchn_upcall_pending,
(int)(sizeof(v->evtchn_pending_sel)*2),
v->evtchn_pending_sel);
@@ -1214,49 +1229,52 @@ irqreturn_t xen_debug_interrupt(int irq, void *dev_id)
printk("\npending:\n ");
for (i = ARRAY_SIZE(sh->evtchn_pending)-1; i >= 0; i--)
- printk("%0*lx%s", (int)sizeof(sh->evtchn_pending[0])*2,
+ printk("%0*"PRI_xen_ulong"%s",
+ (int)sizeof(sh->evtchn_pending[0])*2,
sh->evtchn_pending[i],
i % 8 == 0 ? "\n " : " ");
printk("\nglobal mask:\n ");
for (i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--)
- printk("%0*lx%s",
+ printk("%0*"PRI_xen_ulong"%s",
(int)(sizeof(sh->evtchn_mask[0])*2),
sh->evtchn_mask[i],
i % 8 == 0 ? "\n " : " ");
printk("\nglobally unmasked:\n ");
for (i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--)
- printk("%0*lx%s", (int)(sizeof(sh->evtchn_mask[0])*2),
+ printk("%0*"PRI_xen_ulong"%s",
+ (int)(sizeof(sh->evtchn_mask[0])*2),
sh->evtchn_pending[i] & ~sh->evtchn_mask[i],
i % 8 == 0 ? "\n " : " ");
printk("\nlocal cpu%d mask:\n ", cpu);
- for (i = (NR_EVENT_CHANNELS/BITS_PER_LONG)-1; i >= 0; i--)
- printk("%0*lx%s", (int)(sizeof(cpu_evtchn[0])*2),
+ for (i = (NR_EVENT_CHANNELS/BITS_PER_EVTCHN_WORD)-1; i >= 0; i--)
+ printk("%0*"PRI_xen_ulong"%s", (int)(sizeof(cpu_evtchn[0])*2),
cpu_evtchn[i],
i % 8 == 0 ? "\n " : " ");
printk("\nlocally unmasked:\n ");
for (i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--) {
- unsigned long pending = sh->evtchn_pending[i]
+ xen_ulong_t pending = sh->evtchn_pending[i]
& ~sh->evtchn_mask[i]
& cpu_evtchn[i];
- printk("%0*lx%s", (int)(sizeof(sh->evtchn_mask[0])*2),
+ printk("%0*"PRI_xen_ulong"%s",
+ (int)(sizeof(sh->evtchn_mask[0])*2),
pending, i % 8 == 0 ? "\n " : " ");
}
printk("\npending list:\n");
for (i = 0; i < NR_EVENT_CHANNELS; i++) {
- if (sync_test_bit(i, sh->evtchn_pending)) {
- int word_idx = i / BITS_PER_LONG;
+ if (sync_test_bit(i, BM(sh->evtchn_pending))) {
+ int word_idx = i / BITS_PER_EVTCHN_WORD;
printk(" %d: event %d -> irq %d%s%s%s\n",
cpu_from_evtchn(i), i,
evtchn_to_irq[i],
- sync_test_bit(word_idx, &v->evtchn_pending_sel)
+ sync_test_bit(word_idx, BM(&v->evtchn_pending_sel))
? "" : " l2-clear",
- !sync_test_bit(i, sh->evtchn_mask)
+ !sync_test_bit(i, BM(sh->evtchn_mask))
? "" : " globally-masked",
- sync_test_bit(i, cpu_evtchn)
+ sync_test_bit(i, BM(cpu_evtchn))
? "" : " locally-masked");
}
}
@@ -1273,7 +1291,7 @@ static DEFINE_PER_CPU(unsigned int, current_bit_idx);
/*
* Mask out the i least significant bits of w
*/
-#define MASK_LSBS(w, i) (w & ((~0UL) << i))
+#define MASK_LSBS(w, i) (w & ((~((xen_ulong_t)0UL)) << i))
/*
* Search the CPUs pending events bitmasks. For each one found, map
@@ -1295,18 +1313,19 @@ static void __xen_evtchn_do_upcall(void)
unsigned count;
do {
- unsigned long pending_words;
+ xen_ulong_t pending_words;
vcpu_info->evtchn_upcall_pending = 0;
if (__this_cpu_inc_return(xed_nesting_count) - 1)
goto out;
-#ifndef CONFIG_X86 /* No need for a barrier -- XCHG is a barrier on x86. */
- /* Clear master flag /before/ clearing selector flag. */
- wmb();
-#endif
- pending_words = xchg(&vcpu_info->evtchn_pending_sel, 0);
+ /*
+ * Master flag must be cleared /before/ clearing
+ * selector flag. xchg_xen_ulong must contain an
+ * appropriate barrier.
+ */
+ pending_words = xchg_xen_ulong(&vcpu_info->evtchn_pending_sel, 0);
start_word_idx = __this_cpu_read(current_word_idx);
start_bit_idx = __this_cpu_read(current_bit_idx);
@@ -1314,8 +1333,8 @@ static void __xen_evtchn_do_upcall(void)
word_idx = start_word_idx;
for (i = 0; pending_words != 0; i++) {
- unsigned long pending_bits;
- unsigned long words;
+ xen_ulong_t pending_bits;
+ xen_ulong_t words;
words = MASK_LSBS(pending_words, word_idx);
@@ -1327,7 +1346,7 @@ static void __xen_evtchn_do_upcall(void)
bit_idx = 0;
continue;
}
- word_idx = __ffs(words);
+ word_idx = EVTCHN_FIRST_BIT(words);
pending_bits = active_evtchns(cpu, s, word_idx);
bit_idx = 0; /* usually scan entire word from start */
@@ -1342,7 +1361,7 @@ static void __xen_evtchn_do_upcall(void)
}
do {
- unsigned long bits;
+ xen_ulong_t bits;
int port, irq;
struct irq_desc *desc;
@@ -1352,10 +1371,10 @@ static void __xen_evtchn_do_upcall(void)
if (bits == 0)
break;
- bit_idx = __ffs(bits);
+ bit_idx = EVTCHN_FIRST_BIT(bits);
/* Process port. */
- port = (word_idx * BITS_PER_LONG) + bit_idx;
+ port = (word_idx * BITS_PER_EVTCHN_WORD) + bit_idx;
irq = evtchn_to_irq[port];
if (irq != -1) {
@@ -1364,12 +1383,12 @@ static void __xen_evtchn_do_upcall(void)
generic_handle_irq_desc(irq, desc);
}
- bit_idx = (bit_idx + 1) % BITS_PER_LONG;
+ bit_idx = (bit_idx + 1) % BITS_PER_EVTCHN_WORD;
/* Next caller starts at last processed + 1 */
__this_cpu_write(current_word_idx,
bit_idx ? word_idx :
- (word_idx+1) % BITS_PER_LONG);
+ (word_idx+1) % BITS_PER_EVTCHN_WORD);
__this_cpu_write(current_bit_idx, bit_idx);
} while (bit_idx != 0);
@@ -1377,7 +1396,7 @@ static void __xen_evtchn_do_upcall(void)
if ((word_idx != start_word_idx) || (i != 0))
pending_words &= ~(1UL << word_idx);
- word_idx = (word_idx + 1) % BITS_PER_LONG;
+ word_idx = (word_idx + 1) % BITS_PER_EVTCHN_WORD;
}
BUG_ON(!irqs_disabled());
@@ -1487,8 +1506,8 @@ int resend_irq_on_evtchn(unsigned int irq)
if (!VALID_EVTCHN(evtchn))
return 1;
- masked = sync_test_and_set_bit(evtchn, s->evtchn_mask);
- sync_set_bit(evtchn, s->evtchn_pending);
+ masked = sync_test_and_set_bit(evtchn, BM(s->evtchn_mask));
+ sync_set_bit(evtchn, BM(s->evtchn_pending));
if (!masked)
unmask_evtchn(evtchn);
@@ -1536,8 +1555,8 @@ static int retrigger_dynirq(struct irq_data *data)
if (VALID_EVTCHN(evtchn)) {
int masked;
- masked = sync_test_and_set_bit(evtchn, sh->evtchn_mask);
- sync_set_bit(evtchn, sh->evtchn_pending);
+ masked = sync_test_and_set_bit(evtchn, BM(sh->evtchn_mask));
+ sync_set_bit(evtchn, BM(sh->evtchn_pending));
if (!masked)
unmask_evtchn(evtchn);
ret = 1;