if (group_leader == event) {
struct list_head *list;
+ if (is_software_event(event))
+ event->group_flags |= PERF_GROUP_SOFTWARE;
+
list = ctx_group_list(event, ctx);
list_add_tail(&event->group_entry, list);
} else {
+ if (group_leader->group_flags & PERF_GROUP_SOFTWARE &&
+ !is_software_event(event))
+ group_leader->group_flags &= ~PERF_GROUP_SOFTWARE;
+
list_add_tail(&event->group_entry, &group_leader->sibling_list);
group_leader->nr_siblings++;
}
list = ctx_group_list(event, ctx);
list_move_tail(&sibling->group_entry, list);
sibling->group_leader = sibling;
+
+ /* Inherit group flags from the previous leader */
+ sibling->group_flags = event->group_flags;
}
}
}
/*
- * Return 1 for a group consisting entirely of software events,
- * 0 if the group contains any hardware events.
- */
-static int is_software_only_group(struct perf_event *leader)
-{
- struct perf_event *event;
-
- if (!is_software_event(leader))
- return 0;
-
- list_for_each_entry(event, &leader->sibling_list, group_entry)
- if (!is_software_event(event))
- return 0;
-
- return 1;
-}
-
-/*
* Work out whether we can put this event group on the CPU now.
*/
static int group_can_go_on(struct perf_event *event,
/*
* Groups consisting entirely of software events can always go on.
*/
- if (is_software_only_group(event))
+ if (event->group_flags & PERF_GROUP_SOFTWARE)
return 1;
/*
* If an exclusive group is already on, no other hardware
return 0;
}
-void __perf_event_sched_out(struct perf_event_context *ctx,
- struct perf_cpu_context *cpuctx)
+enum event_type_t {
+ EVENT_FLEXIBLE = 0x1,
+ EVENT_PINNED = 0x2,
+ EVENT_ALL = EVENT_FLEXIBLE | EVENT_PINNED,
+};
+
+static void ctx_sched_out(struct perf_event_context *ctx,
+ struct perf_cpu_context *cpuctx,
+ enum event_type_t event_type)
{
struct perf_event *event;
update_context_time(ctx);
perf_disable();
- if (ctx->nr_active) {
+ if (!ctx->nr_active)
+ goto out_enable;
+
+ if (event_type & EVENT_PINNED)
list_for_each_entry(event, &ctx->pinned_groups, group_entry)
group_sched_out(event, cpuctx, ctx);
+ if (event_type & EVENT_FLEXIBLE)
list_for_each_entry(event, &ctx->flexible_groups, group_entry)
group_sched_out(event, cpuctx, ctx);
- }
+
+ out_enable:
perf_enable();
out:
raw_spin_unlock(&ctx->lock);
rcu_read_unlock();
if (do_switch) {
- __perf_event_sched_out(ctx, cpuctx);
+ ctx_sched_out(ctx, cpuctx, EVENT_ALL);
cpuctx->task_ctx = NULL;
}
}
-/*
- * Called with IRQs disabled
- */
-static void __perf_event_task_sched_out(struct perf_event_context *ctx)
+static void task_ctx_sched_out(struct perf_event_context *ctx,
+ enum event_type_t event_type)
{
struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
if (WARN_ON_ONCE(ctx != cpuctx->task_ctx))
return;
- __perf_event_sched_out(ctx, cpuctx);
+ ctx_sched_out(ctx, cpuctx, event_type);
cpuctx->task_ctx = NULL;
}
/*
* Called with IRQs disabled
*/
-static void perf_event_cpu_sched_out(struct perf_cpu_context *cpuctx)
+static void __perf_event_task_sched_out(struct perf_event_context *ctx)
{
- __perf_event_sched_out(&cpuctx->ctx, cpuctx);
+ task_ctx_sched_out(ctx, EVENT_ALL);
+}
+
+/*
+ * Called with IRQs disabled
+ */
+static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx,
+ enum event_type_t event_type)
+{
+ ctx_sched_out(&cpuctx->ctx, cpuctx, event_type);
}
static void
-__perf_event_sched_in(struct perf_event_context *ctx,
- struct perf_cpu_context *cpuctx)
+ctx_pinned_sched_in(struct perf_event_context *ctx,
+ struct perf_cpu_context *cpuctx,
+ int cpu)
{
- int cpu = smp_processor_id();
struct perf_event *event;
- int can_add_hw = 1;
-
- raw_spin_lock(&ctx->lock);
- ctx->is_active = 1;
- if (likely(!ctx->nr_events))
- goto out;
-
- ctx->timestamp = perf_clock();
-
- perf_disable();
- /*
- * First go through the list and put on any pinned groups
- * in order to give them the best chance of going on.
- */
list_for_each_entry(event, &ctx->pinned_groups, group_entry) {
if (event->state <= PERF_EVENT_STATE_OFF)
continue;
event->state = PERF_EVENT_STATE_ERROR;
}
}
+}
+
+static void
+ctx_flexible_sched_in(struct perf_event_context *ctx,
+ struct perf_cpu_context *cpuctx,
+ int cpu)
+{
+ struct perf_event *event;
+ int can_add_hw = 1;
list_for_each_entry(event, &ctx->flexible_groups, group_entry) {
/* Ignore events in OFF or ERROR state */
if (group_sched_in(event, cpuctx, ctx, cpu))
can_add_hw = 0;
}
+}
+
+static void
+ctx_sched_in(struct perf_event_context *ctx,
+ struct perf_cpu_context *cpuctx,
+ enum event_type_t event_type)
+{
+ int cpu = smp_processor_id();
+
+ raw_spin_lock(&ctx->lock);
+ ctx->is_active = 1;
+ if (likely(!ctx->nr_events))
+ goto out;
+
+ ctx->timestamp = perf_clock();
+
+ perf_disable();
+
+ /*
+ * First go through the list and put on any pinned groups
+ * in order to give them the best chance of going on.
+ */
+ if (event_type & EVENT_PINNED)
+ ctx_pinned_sched_in(ctx, cpuctx, cpu);
+
+ /* Then walk through the lower prio flexible groups */
+ if (event_type & EVENT_FLEXIBLE)
+ ctx_flexible_sched_in(ctx, cpuctx, cpu);
+
perf_enable();
out:
raw_spin_unlock(&ctx->lock);
}
+static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx,
+ enum event_type_t event_type)
+{
+ struct perf_event_context *ctx = &cpuctx->ctx;
+
+ ctx_sched_in(ctx, cpuctx, event_type);
+}
+
+static void task_ctx_sched_in(struct task_struct *task,
+ enum event_type_t event_type)
+{
+ struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
+ struct perf_event_context *ctx = task->perf_event_ctxp;
+
+ if (likely(!ctx))
+ return;
+ if (cpuctx->task_ctx == ctx)
+ return;
+ ctx_sched_in(ctx, cpuctx, event_type);
+ cpuctx->task_ctx = ctx;
+}
/*
* Called from scheduler to add the events of the current task
* with interrupts disabled.
if (likely(!ctx))
return;
+
if (cpuctx->task_ctx == ctx)
return;
- __perf_event_sched_in(ctx, cpuctx);
- cpuctx->task_ctx = ctx;
-}
-static void perf_event_cpu_sched_in(struct perf_cpu_context *cpuctx)
-{
- struct perf_event_context *ctx = &cpuctx->ctx;
+ /*
+ * We want to keep the following priority order:
+ * cpu pinned (that don't need to move), task pinned,
+ * cpu flexible, task flexible.
+ */
+ cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE);
- __perf_event_sched_in(ctx, cpuctx);
+ ctx_sched_in(ctx, cpuctx, EVENT_PINNED);
+ cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE);
+ ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE);
+
+ cpuctx->task_ctx = ctx;
}
#define MAX_INTERRUPTS (~0ULL)
static void perf_log_throttle(struct perf_event *event, int enable);
-static void perf_adjust_period(struct perf_event *event, u64 events)
+static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count)
+{
+ u64 frequency = event->attr.sample_freq;
+ u64 sec = NSEC_PER_SEC;
+ u64 divisor, dividend;
+
+ int count_fls, nsec_fls, frequency_fls, sec_fls;
+
+ count_fls = fls64(count);
+ nsec_fls = fls64(nsec);
+ frequency_fls = fls64(frequency);
+ sec_fls = 30;
+
+ /*
+ * We got @count in @nsec, with a target of sample_freq HZ
+ * the target period becomes:
+ *
+ * @count * 10^9
+ * period = -------------------
+ * @nsec * sample_freq
+ *
+ */
+
+ /*
+ * Reduce accuracy by one bit such that @a and @b converge
+ * to a similar magnitude.
+ */
+#define REDUCE_FLS(a, b) \
+do { \
+ if (a##_fls > b##_fls) { \
+ a >>= 1; \
+ a##_fls--; \
+ } else { \
+ b >>= 1; \
+ b##_fls--; \
+ } \
+} while (0)
+
+ /*
+ * Reduce accuracy until either term fits in a u64, then proceed with
+ * the other, so that finally we can do a u64/u64 division.
+ */
+ while (count_fls + sec_fls > 64 && nsec_fls + frequency_fls > 64) {
+ REDUCE_FLS(nsec, frequency);
+ REDUCE_FLS(sec, count);
+ }
+
+ if (count_fls + sec_fls > 64) {
+ divisor = nsec * frequency;
+
+ while (count_fls + sec_fls > 64) {
+ REDUCE_FLS(count, sec);
+ divisor >>= 1;
+ }
+
+ dividend = count * sec;
+ } else {
+ dividend = count * sec;
+
+ while (nsec_fls + frequency_fls > 64) {
+ REDUCE_FLS(nsec, frequency);
+ dividend >>= 1;
+ }
+
+ divisor = nsec * frequency;
+ }
+
+ return div64_u64(dividend, divisor);
+}
+
+static void perf_adjust_period(struct perf_event *event, u64 nsec, u64 count)
{
struct hw_perf_event *hwc = &event->hw;
u64 period, sample_period;
s64 delta;
- events *= hwc->sample_period;
- period = div64_u64(events, event->attr.sample_freq);
+ period = perf_calculate_period(event, nsec, count);
delta = (s64)(period - hwc->sample_period);
delta = (delta + 7) / 8; /* low pass filter */
sample_period = 1;
hwc->sample_period = sample_period;
+
+ if (atomic64_read(&hwc->period_left) > 8*sample_period) {
+ perf_disable();
+ event->pmu->disable(event);
+ atomic64_set(&hwc->period_left, 0);
+ event->pmu->enable(event);
+ perf_enable();
+ }
}
static void perf_ctx_adjust_freq(struct perf_event_context *ctx)
{
struct perf_event *event;
struct hw_perf_event *hwc;
- u64 interrupts, freq;
+ u64 interrupts, now;
+ s64 delta;
raw_spin_lock(&ctx->lock);
list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
if (interrupts == MAX_INTERRUPTS) {
perf_log_throttle(event, 1);
event->pmu->unthrottle(event);
- interrupts = 2*sysctl_perf_event_sample_rate/HZ;
}
if (!event->attr.freq || !event->attr.sample_freq)
continue;
- /*
- * if the specified freq < HZ then we need to skip ticks
- */
- if (event->attr.sample_freq < HZ) {
- freq = event->attr.sample_freq;
-
- hwc->freq_count += freq;
- hwc->freq_interrupts += interrupts;
-
- if (hwc->freq_count < HZ)
- continue;
-
- interrupts = hwc->freq_interrupts;
- hwc->freq_interrupts = 0;
- hwc->freq_count -= HZ;
- } else
- freq = HZ;
-
- perf_adjust_period(event, freq * interrupts);
+ event->pmu->read(event);
+ now = atomic64_read(&event->count);
+ delta = now - hwc->freq_count_stamp;
+ hwc->freq_count_stamp = now;
- /*
- * In order to avoid being stalled by an (accidental) huge
- * sample period, force reset the sample period if we didn't
- * get any events in this freq period.
- */
- if (!interrupts) {
- perf_disable();
- event->pmu->disable(event);
- atomic64_set(&hwc->period_left, 0);
- event->pmu->enable(event);
- perf_enable();
- }
+ if (delta > 0)
+ perf_adjust_period(event, TICK_NSEC, delta);
}
raw_spin_unlock(&ctx->lock);
}
*/
static void rotate_ctx(struct perf_event_context *ctx)
{
- struct perf_event *event;
-
if (!ctx->nr_events)
return;
raw_spin_lock(&ctx->lock);
- /*
- * Rotate the first entry last (works just fine for group events too):
- */
- perf_disable();
- list_for_each_entry(event, &ctx->pinned_groups, group_entry) {
- list_move_tail(&event->group_entry, &ctx->pinned_groups);
- break;
- }
- list_for_each_entry(event, &ctx->flexible_groups, group_entry) {
- list_move_tail(&event->group_entry, &ctx->flexible_groups);
- break;
- }
- perf_enable();
+ /* Rotate the first entry last of non-pinned groups */
+ list_rotate_left(&ctx->flexible_groups);
raw_spin_unlock(&ctx->lock);
}
cpuctx = &__get_cpu_var(perf_cpu_context);
ctx = curr->perf_event_ctxp;
+ perf_disable();
+
perf_ctx_adjust_freq(&cpuctx->ctx);
if (ctx)
perf_ctx_adjust_freq(ctx);
- perf_event_cpu_sched_out(cpuctx);
+ cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE);
if (ctx)
- __perf_event_task_sched_out(ctx);
+ task_ctx_sched_out(ctx, EVENT_FLEXIBLE);
rotate_ctx(&cpuctx->ctx);
if (ctx)
rotate_ctx(ctx);
- perf_event_cpu_sched_in(cpuctx);
+ cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE);
if (ctx)
- perf_event_task_sched_in(curr);
+ task_ctx_sched_in(curr, EVENT_FLEXIBLE);
+
+ perf_enable();
}
static int event_enable_on_exec(struct perf_event *event,
static int perf_event_task_match(struct perf_event *event)
{
+ if (event->state != PERF_EVENT_STATE_ACTIVE)
+ return 0;
+
if (event->cpu != -1 && event->cpu != smp_processor_id())
return 0;
static int perf_event_comm_match(struct perf_event *event)
{
+ if (event->state != PERF_EVENT_STATE_ACTIVE)
+ return 0;
+
if (event->cpu != -1 && event->cpu != smp_processor_id())
return 0;
static int perf_event_mmap_match(struct perf_event *event,
struct perf_mmap_event *mmap_event)
{
+ if (event->state != PERF_EVENT_STATE_ACTIVE)
+ return 0;
+
if (event->cpu != -1 && event->cpu != smp_processor_id())
return 0;
if (event->attr.freq) {
u64 now = perf_clock();
- s64 delta = now - hwc->freq_stamp;
+ s64 delta = now - hwc->freq_time_stamp;
- hwc->freq_stamp = now;
+ hwc->freq_time_stamp = now;
- if (delta > 0 && delta < TICK_NSEC)
- perf_adjust_period(event, NSEC_PER_SEC / (int)delta);
+ if (delta > 0 && delta < 2*TICK_NSEC)
+ perf_adjust_period(event, delta, hwc->last_period);
}
/*
else
child_event->state = PERF_EVENT_STATE_OFF;
- if (parent_event->attr.freq)
- child_event->hw.sample_period = parent_event->hw.sample_period;
+ if (parent_event->attr.freq) {
+ u64 sample_period = parent_event->hw.sample_period;
+ struct hw_perf_event *hwc = &child_event->hw;
+
+ hwc->sample_period = sample_period;
+ hwc->last_period = sample_period;
+
+ atomic64_set(&hwc->period_left, sample_period);
+ }
child_event->overflow_handler = parent_event->overflow_handler;
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff