* perf_sched_events : >0 events exist
* perf_cgroup_events: >0 per-cpu cgroup events exist on this cpu
*/
-struct jump_label_key perf_sched_events __read_mostly;
+struct jump_label_key_deferred perf_sched_events __read_mostly;
static DEFINE_PER_CPU(atomic_t, perf_cgroup_events);
static atomic_t nr_mmap_events __read_mostly;
if (!is_software_event(event))
cpuctx->active_oncpu--;
ctx->nr_active--;
+ if (event->attr.freq && event->attr.sample_freq)
+ ctx->nr_freq--;
if (event->attr.exclusive || !cpuctx->active_oncpu)
cpuctx->exclusive = 0;
}
}
raw_spin_unlock_irq(&ctx->lock);
}
+EXPORT_SYMBOL_GPL(perf_event_disable);
static void perf_set_shadow_time(struct perf_event *event,
struct perf_event_context *ctx,
if (!is_software_event(event))
cpuctx->active_oncpu++;
ctx->nr_active++;
+ if (event->attr.freq && event->attr.sample_freq)
+ ctx->nr_freq++;
if (event->attr.exclusive)
cpuctx->exclusive = 1;
* Note: this works for group members as well as group leaders
* since the non-leader members' sibling_lists will be empty.
*/
-static void __perf_event_mark_enabled(struct perf_event *event,
- struct perf_event_context *ctx)
+static void __perf_event_mark_enabled(struct perf_event *event)
{
struct perf_event *sub;
u64 tstamp = perf_event_time(event);
*/
perf_cgroup_set_timestamp(current, ctx);
- __perf_event_mark_enabled(event, ctx);
+ __perf_event_mark_enabled(event);
if (!event_filter_match(event)) {
if (is_cgroup_event(event))
retry:
if (!ctx->is_active) {
- __perf_event_mark_enabled(event, ctx);
+ __perf_event_mark_enabled(event);
goto out;
}
out:
raw_spin_unlock_irq(&ctx->lock);
}
+EXPORT_SYMBOL_GPL(perf_event_enable);
int perf_event_refresh(struct perf_event *event, int refresh)
{
u64 interrupts, now;
s64 delta;
+ if (!ctx->nr_freq)
+ return;
+
list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
if (event->state != PERF_EVENT_STATE_ACTIVE)
continue;
{
u64 interval = (u64)cpuctx->jiffies_interval * TICK_NSEC;
struct perf_event_context *ctx = NULL;
- int rotate = 0, remove = 1;
+ int rotate = 0, remove = 1, freq = 0;
if (cpuctx->ctx.nr_events) {
remove = 0;
if (cpuctx->ctx.nr_events != cpuctx->ctx.nr_active)
rotate = 1;
+ if (cpuctx->ctx.nr_freq)
+ freq = 1;
}
ctx = cpuctx->task_ctx;
remove = 0;
if (ctx->nr_events != ctx->nr_active)
rotate = 1;
+ if (ctx->nr_freq)
+ freq = 1;
}
+ if (!rotate && !freq)
+ goto done;
+
perf_ctx_lock(cpuctx, cpuctx->task_ctx);
perf_pmu_disable(cpuctx->ctx.pmu);
- perf_ctx_adjust_freq(&cpuctx->ctx, interval);
- if (ctx)
- perf_ctx_adjust_freq(ctx, interval);
- if (!rotate)
- goto done;
+ if (freq) {
+ perf_ctx_adjust_freq(&cpuctx->ctx, interval);
+ if (ctx)
+ perf_ctx_adjust_freq(ctx, interval);
+ }
- cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE);
- if (ctx)
- ctx_sched_out(ctx, cpuctx, EVENT_FLEXIBLE);
+ if (rotate) {
+ cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE);
+ if (ctx)
+ ctx_sched_out(ctx, cpuctx, EVENT_FLEXIBLE);
- rotate_ctx(&cpuctx->ctx);
- if (ctx)
- rotate_ctx(ctx);
+ rotate_ctx(&cpuctx->ctx);
+ if (ctx)
+ rotate_ctx(ctx);
- perf_event_sched_in(cpuctx, ctx, current);
+ perf_event_sched_in(cpuctx, ctx, current);
+ }
+
+ perf_pmu_enable(cpuctx->ctx.pmu);
+ perf_ctx_unlock(cpuctx, cpuctx->task_ctx);
done:
if (remove)
list_del_init(&cpuctx->rotation_list);
-
- perf_pmu_enable(cpuctx->ctx.pmu);
- perf_ctx_unlock(cpuctx, cpuctx->task_ctx);
}
void perf_event_task_tick(void)
if (event->state >= PERF_EVENT_STATE_INACTIVE)
return 0;
- __perf_event_mark_enabled(event, ctx);
+ __perf_event_mark_enabled(event);
return 1;
}
raw_spin_lock(&ctx->lock);
task_ctx_sched_out(ctx);
- list_for_each_entry(event, &ctx->pinned_groups, group_entry) {
- ret = event_enable_on_exec(event, ctx);
- if (ret)
- enabled = 1;
- }
-
- list_for_each_entry(event, &ctx->flexible_groups, group_entry) {
+ list_for_each_entry(event, &ctx->event_list, event_entry) {
ret = event_enable_on_exec(event, ctx);
if (ret)
enabled = 1;
return perf_event_count(event);
}
-/*
- * Callchain support
- */
-
-struct callchain_cpus_entries {
- struct rcu_head rcu_head;
- struct perf_callchain_entry *cpu_entries[0];
-};
-
-static DEFINE_PER_CPU(int, callchain_recursion[PERF_NR_CONTEXTS]);
-static atomic_t nr_callchain_events;
-static DEFINE_MUTEX(callchain_mutex);
-struct callchain_cpus_entries *callchain_cpus_entries;
-
-
-__weak void perf_callchain_kernel(struct perf_callchain_entry *entry,
- struct pt_regs *regs)
-{
-}
-
-__weak void perf_callchain_user(struct perf_callchain_entry *entry,
- struct pt_regs *regs)
-{
-}
-
-static void release_callchain_buffers_rcu(struct rcu_head *head)
-{
- struct callchain_cpus_entries *entries;
- int cpu;
-
- entries = container_of(head, struct callchain_cpus_entries, rcu_head);
-
- for_each_possible_cpu(cpu)
- kfree(entries->cpu_entries[cpu]);
-
- kfree(entries);
-}
-
-static void release_callchain_buffers(void)
-{
- struct callchain_cpus_entries *entries;
-
- entries = callchain_cpus_entries;
- rcu_assign_pointer(callchain_cpus_entries, NULL);
- call_rcu(&entries->rcu_head, release_callchain_buffers_rcu);
-}
-
-static int alloc_callchain_buffers(void)
-{
- int cpu;
- int size;
- struct callchain_cpus_entries *entries;
-
- /*
- * We can't use the percpu allocation API for data that can be
- * accessed from NMI. Use a temporary manual per cpu allocation
- * until that gets sorted out.
- */
- size = offsetof(struct callchain_cpus_entries, cpu_entries[nr_cpu_ids]);
-
- entries = kzalloc(size, GFP_KERNEL);
- if (!entries)
- return -ENOMEM;
-
- size = sizeof(struct perf_callchain_entry) * PERF_NR_CONTEXTS;
-
- for_each_possible_cpu(cpu) {
- entries->cpu_entries[cpu] = kmalloc_node(size, GFP_KERNEL,
- cpu_to_node(cpu));
- if (!entries->cpu_entries[cpu])
- goto fail;
- }
-
- rcu_assign_pointer(callchain_cpus_entries, entries);
-
- return 0;
-
-fail:
- for_each_possible_cpu(cpu)
- kfree(entries->cpu_entries[cpu]);
- kfree(entries);
-
- return -ENOMEM;
-}
-
-static int get_callchain_buffers(void)
-{
- int err = 0;
- int count;
-
- mutex_lock(&callchain_mutex);
-
- count = atomic_inc_return(&nr_callchain_events);
- if (WARN_ON_ONCE(count < 1)) {
- err = -EINVAL;
- goto exit;
- }
-
- if (count > 1) {
- /* If the allocation failed, give up */
- if (!callchain_cpus_entries)
- err = -ENOMEM;
- goto exit;
- }
-
- err = alloc_callchain_buffers();
- if (err)
- release_callchain_buffers();
-exit:
- mutex_unlock(&callchain_mutex);
-
- return err;
-}
-
-static void put_callchain_buffers(void)
-{
- if (atomic_dec_and_mutex_lock(&nr_callchain_events, &callchain_mutex)) {
- release_callchain_buffers();
- mutex_unlock(&callchain_mutex);
- }
-}
-
-static int get_recursion_context(int *recursion)
-{
- int rctx;
-
- if (in_nmi())
- rctx = 3;
- else if (in_irq())
- rctx = 2;
- else if (in_softirq())
- rctx = 1;
- else
- rctx = 0;
-
- if (recursion[rctx])
- return -1;
-
- recursion[rctx]++;
- barrier();
-
- return rctx;
-}
-
-static inline void put_recursion_context(int *recursion, int rctx)
-{
- barrier();
- recursion[rctx]--;
-}
-
-static struct perf_callchain_entry *get_callchain_entry(int *rctx)
-{
- int cpu;
- struct callchain_cpus_entries *entries;
-
- *rctx = get_recursion_context(__get_cpu_var(callchain_recursion));
- if (*rctx == -1)
- return NULL;
-
- entries = rcu_dereference(callchain_cpus_entries);
- if (!entries)
- return NULL;
-
- cpu = smp_processor_id();
-
- return &entries->cpu_entries[cpu][*rctx];
-}
-
-static void
-put_callchain_entry(int rctx)
-{
- put_recursion_context(__get_cpu_var(callchain_recursion), rctx);
-}
-
-static struct perf_callchain_entry *perf_callchain(struct pt_regs *regs)
-{
- int rctx;
- struct perf_callchain_entry *entry;
-
-
- entry = get_callchain_entry(&rctx);
- if (rctx == -1)
- return NULL;
-
- if (!entry)
- goto exit_put;
-
- entry->nr = 0;
-
- if (!user_mode(regs)) {
- perf_callchain_store(entry, PERF_CONTEXT_KERNEL);
- perf_callchain_kernel(entry, regs);
- if (current->mm)
- regs = task_pt_regs(current);
- else
- regs = NULL;
- }
-
- if (regs) {
- perf_callchain_store(entry, PERF_CONTEXT_USER);
- perf_callchain_user(entry, regs);
- }
-
-exit_put:
- put_callchain_entry(rctx);
-
- return entry;
-}
-
/*
* Initialize the perf_event context in a task_struct:
*/
if (!event->parent) {
if (event->attach_state & PERF_ATTACH_TASK)
- jump_label_dec(&perf_sched_events);
+ jump_label_dec_deferred(&perf_sched_events);
if (event->attr.mmap || event->attr.mmap_data)
atomic_dec(&nr_mmap_events);
if (event->attr.comm)
put_callchain_buffers();
if (is_cgroup_event(event)) {
atomic_dec(&per_cpu(perf_cgroup_events, event->cpu));
- jump_label_dec(&perf_sched_events);
+ jump_label_dec_deferred(&perf_sched_events);
}
}
rcu_read_lock();
rb = rcu_dereference(event->rb);
- list_for_each_entry_rcu(event, &rb->event_list, rb_entry) {
+ if (!rb)
+ goto unlock;
+
+ list_for_each_entry_rcu(event, &rb->event_list, rb_entry)
wake_up_all(&event->waitq);
- }
+
+unlock:
rcu_read_unlock();
}
struct hw_perf_event *hwc = &event->hw;
int throttle = 0;
- data->period = event->hw.last_period;
if (!overflow)
overflow = perf_swevent_set_period(event);
if (!is_sampling_event(event))
return;
+ if ((event->attr.sample_type & PERF_SAMPLE_PERIOD) && !event->attr.freq) {
+ data->period = nr;
+ return perf_swevent_overflow(event, 1, data, regs);
+ } else
+ data->period = event->hw.last_period;
+
if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq)
return perf_swevent_overflow(event, 1, data, regs);
regs = get_irq_regs();
if (regs && !perf_exclude_event(event, regs)) {
- if (!(event->attr.exclude_idle && current->pid == 0))
+ if (!(event->attr.exclude_idle && is_idle_task(current)))
if (perf_event_overflow(event, &data, regs))
ret = HRTIMER_NORESTART;
}
if (!event->parent) {
if (event->attach_state & PERF_ATTACH_TASK)
- jump_label_inc(&perf_sched_events);
+ jump_label_inc(&perf_sched_events.key);
if (event->attr.mmap || event->attr.mmap_data)
atomic_inc(&nr_mmap_events);
if (event->attr.comm)
* - that may need work on context switch
*/
atomic_inc(&per_cpu(perf_cgroup_events, event->cpu));
- jump_label_inc(&perf_sched_events);
+ jump_label_inc(&perf_sched_events.key);
}
/*
ret = init_hw_breakpoint();
WARN(ret, "hw_breakpoint initialization failed with: %d", ret);
+
+ /* do not patch jump label more than once per second */
+ jump_label_rate_limit(&perf_sched_events, HZ);
}
static int __init perf_event_sysfs_init(void)
projects / cascardo / linux.git / blobdiff