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Diffstat (limited to 'arch/arm/kernel/perf_event.c')
-rw-r--r--arch/arm/kernel/perf_event.c242
1 files changed, 117 insertions, 125 deletions
diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c
index de12536d687..49643b1467e 100644
--- a/arch/arm/kernel/perf_event.c
+++ b/arch/arm/kernel/perf_event.c
@@ -123,6 +123,12 @@ armpmu_get_max_events(void)
}
EXPORT_SYMBOL_GPL(armpmu_get_max_events);
+int perf_num_counters(void)
+{
+ return armpmu_get_max_events();
+}
+EXPORT_SYMBOL_GPL(perf_num_counters);
+
#define HW_OP_UNSUPPORTED 0xFFFF
#define C(_x) \
@@ -164,20 +170,20 @@ armpmu_event_set_period(struct perf_event *event,
struct hw_perf_event *hwc,
int idx)
{
- s64 left = atomic64_read(&hwc->period_left);
+ s64 left = local64_read(&hwc->period_left);
s64 period = hwc->sample_period;
int ret = 0;
if (unlikely(left <= -period)) {
left = period;
- atomic64_set(&hwc->period_left, left);
+ local64_set(&hwc->period_left, left);
hwc->last_period = period;
ret = 1;
}
if (unlikely(left <= 0)) {
left += period;
- atomic64_set(&hwc->period_left, left);
+ local64_set(&hwc->period_left, left);
hwc->last_period = period;
ret = 1;
}
@@ -185,7 +191,7 @@ armpmu_event_set_period(struct perf_event *event,
if (left > (s64)armpmu->max_period)
left = armpmu->max_period;
- atomic64_set(&hwc->prev_count, (u64)-left);
+ local64_set(&hwc->prev_count, (u64)-left);
armpmu->write_counter(idx, (u64)(-left) & 0xffffffff);
@@ -204,63 +210,73 @@ armpmu_event_update(struct perf_event *event,
u64 delta;
again:
- prev_raw_count = atomic64_read(&hwc->prev_count);
+ prev_raw_count = local64_read(&hwc->prev_count);
new_raw_count = armpmu->read_counter(idx);
- if (atomic64_cmpxchg(&hwc->prev_count, prev_raw_count,
+ if (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
new_raw_count) != prev_raw_count)
goto again;
delta = (new_raw_count << shift) - (prev_raw_count << shift);
delta >>= shift;
- atomic64_add(delta, &event->count);
- atomic64_sub(delta, &hwc->period_left);
+ local64_add(delta, &event->count);
+ local64_sub(delta, &hwc->period_left);
return new_raw_count;
}
static void
-armpmu_disable(struct perf_event *event)
+armpmu_read(struct perf_event *event)
{
- struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
struct hw_perf_event *hwc = &event->hw;
- int idx = hwc->idx;
-
- WARN_ON(idx < 0);
-
- clear_bit(idx, cpuc->active_mask);
- armpmu->disable(hwc, idx);
-
- barrier();
- armpmu_event_update(event, hwc, idx);
- cpuc->events[idx] = NULL;
- clear_bit(idx, cpuc->used_mask);
+ /* Don't read disabled counters! */
+ if (hwc->idx < 0)
+ return;
- perf_event_update_userpage(event);
+ armpmu_event_update(event, hwc, hwc->idx);
}
static void
-armpmu_read(struct perf_event *event)
+armpmu_stop(struct perf_event *event, int flags)
{
struct hw_perf_event *hwc = &event->hw;
- /* Don't read disabled counters! */
- if (hwc->idx < 0)
+ if (!armpmu)
return;
- armpmu_event_update(event, hwc, hwc->idx);
+ /*
+ * ARM pmu always has to update the counter, so ignore
+ * PERF_EF_UPDATE, see comments in armpmu_start().
+ */
+ if (!(hwc->state & PERF_HES_STOPPED)) {
+ armpmu->disable(hwc, hwc->idx);
+ barrier(); /* why? */
+ armpmu_event_update(event, hwc, hwc->idx);
+ hwc->state |= PERF_HES_STOPPED | PERF_HES_UPTODATE;
+ }
}
static void
-armpmu_unthrottle(struct perf_event *event)
+armpmu_start(struct perf_event *event, int flags)
{
struct hw_perf_event *hwc = &event->hw;
+ if (!armpmu)
+ return;
+
+ /*
+ * ARM pmu always has to reprogram the period, so ignore
+ * PERF_EF_RELOAD, see the comment below.
+ */
+ if (flags & PERF_EF_RELOAD)
+ WARN_ON_ONCE(!(hwc->state & PERF_HES_UPTODATE));
+
+ hwc->state = 0;
/*
* Set the period again. Some counters can't be stopped, so when we
- * were throttled we simply disabled the IRQ source and the counter
+ * were stopped we simply disabled the IRQ source and the counter
* may have been left counting. If we don't do this step then we may
* get an interrupt too soon or *way* too late if the overflow has
* happened since disabling.
@@ -269,14 +285,33 @@ armpmu_unthrottle(struct perf_event *event)
armpmu->enable(hwc, hwc->idx);
}
+static void
+armpmu_del(struct perf_event *event, int flags)
+{
+ struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
+ struct hw_perf_event *hwc = &event->hw;
+ int idx = hwc->idx;
+
+ WARN_ON(idx < 0);
+
+ clear_bit(idx, cpuc->active_mask);
+ armpmu_stop(event, PERF_EF_UPDATE);
+ cpuc->events[idx] = NULL;
+ clear_bit(idx, cpuc->used_mask);
+
+ perf_event_update_userpage(event);
+}
+
static int
-armpmu_enable(struct perf_event *event)
+armpmu_add(struct perf_event *event, int flags)
{
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
struct hw_perf_event *hwc = &event->hw;
int idx;
int err = 0;
+ perf_pmu_disable(event->pmu);
+
/* If we don't have a space for the counter then finish early. */
idx = armpmu->get_event_idx(cpuc, hwc);
if (idx < 0) {
@@ -293,25 +328,19 @@ armpmu_enable(struct perf_event *event)
cpuc->events[idx] = event;
set_bit(idx, cpuc->active_mask);
- /* Set the period for the event. */
- armpmu_event_set_period(event, hwc, idx);
-
- /* Enable the event. */
- armpmu->enable(hwc, idx);
+ hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
+ if (flags & PERF_EF_START)
+ armpmu_start(event, PERF_EF_RELOAD);
/* Propagate our changes to the userspace mapping. */
perf_event_update_userpage(event);
out:
+ perf_pmu_enable(event->pmu);
return err;
}
-static struct pmu pmu = {
- .enable = armpmu_enable,
- .disable = armpmu_disable,
- .unthrottle = armpmu_unthrottle,
- .read = armpmu_read,
-};
+static struct pmu pmu;
static int
validate_event(struct cpu_hw_events *cpuc,
@@ -319,8 +348,8 @@ validate_event(struct cpu_hw_events *cpuc,
{
struct hw_perf_event fake_event = event->hw;
- if (event->pmu && event->pmu != &pmu)
- return 0;
+ if (event->pmu != &pmu || event->state <= PERF_EVENT_STATE_OFF)
+ return 1;
return armpmu->get_event_idx(cpuc, &fake_event) >= 0;
}
@@ -478,7 +507,7 @@ __hw_perf_event_init(struct perf_event *event)
if (!hwc->sample_period) {
hwc->sample_period = armpmu->max_period;
hwc->last_period = hwc->sample_period;
- atomic64_set(&hwc->period_left, hwc->sample_period);
+ local64_set(&hwc->period_left, hwc->sample_period);
}
err = 0;
@@ -491,20 +520,29 @@ __hw_perf_event_init(struct perf_event *event)
return err;
}
-const struct pmu *
-hw_perf_event_init(struct perf_event *event)
+static int armpmu_event_init(struct perf_event *event)
{
int err = 0;
+ switch (event->attr.type) {
+ case PERF_TYPE_RAW:
+ case PERF_TYPE_HARDWARE:
+ case PERF_TYPE_HW_CACHE:
+ break;
+
+ default:
+ return -ENOENT;
+ }
+
if (!armpmu)
- return ERR_PTR(-ENODEV);
+ return -ENODEV;
event->destroy = hw_perf_event_destroy;
if (!atomic_inc_not_zero(&active_events)) {
- if (atomic_read(&active_events) > perf_max_events) {
+ if (atomic_read(&active_events) > armpmu->num_events) {
atomic_dec(&active_events);
- return ERR_PTR(-ENOSPC);
+ return -ENOSPC;
}
mutex_lock(&pmu_reserve_mutex);
@@ -518,17 +556,16 @@ hw_perf_event_init(struct perf_event *event)
}
if (err)
- return ERR_PTR(err);
+ return err;
err = __hw_perf_event_init(event);
if (err)
hw_perf_event_destroy(event);
- return err ? ERR_PTR(err) : &pmu;
+ return err;
}
-void
-hw_perf_enable(void)
+static void armpmu_enable(struct pmu *pmu)
{
/* Enable all of the perf events on hardware. */
int idx;
@@ -549,13 +586,23 @@ hw_perf_enable(void)
armpmu->start();
}
-void
-hw_perf_disable(void)
+static void armpmu_disable(struct pmu *pmu)
{
if (armpmu)
armpmu->stop();
}
+static struct pmu pmu = {
+ .pmu_enable = armpmu_enable,
+ .pmu_disable = armpmu_disable,
+ .event_init = armpmu_event_init,
+ .add = armpmu_add,
+ .del = armpmu_del,
+ .start = armpmu_start,
+ .stop = armpmu_stop,
+ .read = armpmu_read,
+};
+
/*
* ARMv6 Performance counter handling code.
*
@@ -1041,11 +1088,11 @@ armv6pmu_handle_irq(int irq_num,
/*
* Handle the pending perf events.
*
- * Note: this call *must* be run with interrupts enabled. For
- * platforms that can have the PMU interrupts raised as a PMI, this
+ * Note: this call *must* be run with interrupts disabled. For
+ * platforms that can have the PMU interrupts raised as an NMI, this
* will not work.
*/
- perf_event_do_pending();
+ irq_work_run();
return IRQ_HANDLED;
}
@@ -2017,11 +2064,11 @@ static irqreturn_t armv7pmu_handle_irq(int irq_num, void *dev)
/*
* Handle the pending perf events.
*
- * Note: this call *must* be run with interrupts enabled. For
- * platforms that can have the PMU interrupts raised as a PMI, this
+ * Note: this call *must* be run with interrupts disabled. For
+ * platforms that can have the PMU interrupts raised as an NMI, this
* will not work.
*/
- perf_event_do_pending();
+ irq_work_run();
return IRQ_HANDLED;
}
@@ -2389,7 +2436,7 @@ xscale1pmu_handle_irq(int irq_num, void *dev)
armpmu->disable(hwc, idx);
}
- perf_event_do_pending();
+ irq_work_run();
/*
* Re-enable the PMU.
@@ -2716,7 +2763,7 @@ xscale2pmu_handle_irq(int irq_num, void *dev)
armpmu->disable(hwc, idx);
}
- perf_event_do_pending();
+ irq_work_run();
/*
* Re-enable the PMU.
@@ -2933,14 +2980,12 @@ init_hw_perf_events(void)
armpmu = &armv6pmu;
memcpy(armpmu_perf_cache_map, armv6_perf_cache_map,
sizeof(armv6_perf_cache_map));
- perf_max_events = armv6pmu.num_events;
break;
case 0xB020: /* ARM11mpcore */
armpmu = &armv6mpcore_pmu;
memcpy(armpmu_perf_cache_map,
armv6mpcore_perf_cache_map,
sizeof(armv6mpcore_perf_cache_map));
- perf_max_events = armv6mpcore_pmu.num_events;
break;
case 0xC080: /* Cortex-A8 */
armv7pmu.id = ARM_PERF_PMU_ID_CA8;
@@ -2952,7 +2997,6 @@ init_hw_perf_events(void)
/* Reset PMNC and read the nb of CNTx counters
supported */
armv7pmu.num_events = armv7_reset_read_pmnc();
- perf_max_events = armv7pmu.num_events;
break;
case 0xC090: /* Cortex-A9 */
armv7pmu.id = ARM_PERF_PMU_ID_CA9;
@@ -2964,7 +3008,6 @@ init_hw_perf_events(void)
/* Reset PMNC and read the nb of CNTx counters
supported */
armv7pmu.num_events = armv7_reset_read_pmnc();
- perf_max_events = armv7pmu.num_events;
break;
}
/* Intel CPUs [xscale]. */
@@ -2975,13 +3018,11 @@ init_hw_perf_events(void)
armpmu = &xscale1pmu;
memcpy(armpmu_perf_cache_map, xscale_perf_cache_map,
sizeof(xscale_perf_cache_map));
- perf_max_events = xscale1pmu.num_events;
break;
case 2:
armpmu = &xscale2pmu;
memcpy(armpmu_perf_cache_map, xscale_perf_cache_map,
sizeof(xscale_perf_cache_map));
- perf_max_events = xscale2pmu.num_events;
break;
}
}
@@ -2991,9 +3032,10 @@ init_hw_perf_events(void)
arm_pmu_names[armpmu->id], armpmu->num_events);
} else {
pr_info("no hardware support available\n");
- perf_max_events = -1;
}
+ perf_pmu_register(&pmu);
+
return 0;
}
arch_initcall(init_hw_perf_events);
@@ -3001,13 +3043,6 @@ arch_initcall(init_hw_perf_events);
/*
* Callchain handling code.
*/
-static inline void
-callchain_store(struct perf_callchain_entry *entry,
- u64 ip)
-{
- if (entry->nr < PERF_MAX_STACK_DEPTH)
- entry->ip[entry->nr++] = ip;
-}
/*
* The registers we're interested in are at the end of the variable
@@ -3039,7 +3074,7 @@ user_backtrace(struct frame_tail *tail,
if (__copy_from_user_inatomic(&buftail, tail, sizeof(buftail)))
return NULL;
- callchain_store(entry, buftail.lr);
+ perf_callchain_store(entry, buftail.lr);
/*
* Frame pointers should strictly progress back up the stack
@@ -3051,16 +3086,11 @@ user_backtrace(struct frame_tail *tail,
return buftail.fp - 1;
}
-static void
-perf_callchain_user(struct pt_regs *regs,
- struct perf_callchain_entry *entry)
+void
+perf_callchain_user(struct perf_callchain_entry *entry, struct pt_regs *regs)
{
struct frame_tail *tail;
- callchain_store(entry, PERF_CONTEXT_USER);
-
- if (!user_mode(regs))
- regs = task_pt_regs(current);
tail = (struct frame_tail *)regs->ARM_fp - 1;
@@ -3078,56 +3108,18 @@ callchain_trace(struct stackframe *fr,
void *data)
{
struct perf_callchain_entry *entry = data;
- callchain_store(entry, fr->pc);
+ perf_callchain_store(entry, fr->pc);
return 0;
}
-static void
-perf_callchain_kernel(struct pt_regs *regs,
- struct perf_callchain_entry *entry)
+void
+perf_callchain_kernel(struct perf_callchain_entry *entry, struct pt_regs *regs)
{
struct stackframe fr;
- callchain_store(entry, PERF_CONTEXT_KERNEL);
fr.fp = regs->ARM_fp;
fr.sp = regs->ARM_sp;
fr.lr = regs->ARM_lr;
fr.pc = regs->ARM_pc;
walk_stackframe(&fr, callchain_trace, entry);
}
-
-static void
-perf_do_callchain(struct pt_regs *regs,
- struct perf_callchain_entry *entry)
-{
- int is_user;
-
- if (!regs)
- return;
-
- is_user = user_mode(regs);
-
- if (!current || !current->pid)
- return;
-
- if (is_user && current->state != TASK_RUNNING)
- return;
-
- if (!is_user)
- perf_callchain_kernel(regs, entry);
-
- if (current->mm)
- perf_callchain_user(regs, entry);
-}
-
-static DEFINE_PER_CPU(struct perf_callchain_entry, pmc_irq_entry);
-
-struct perf_callchain_entry *
-perf_callchain(struct pt_regs *regs)
-{
- struct perf_callchain_entry *entry = &__get_cpu_var(pmc_irq_entry);
-
- entry->nr = 0;
- perf_do_callchain(regs, entry);
- return entry;
-}