static DEFINE_PER_CPU(atomic_t, perf_cgroup_events);
static DEFINE_PER_CPU(int, perf_sched_cb_usages);
+static DEFINE_PER_CPU(struct pmu_event_list, pmu_sb_events);
static atomic_t nr_mmap_events __read_mostly;
static atomic_t nr_comm_events __read_mostly;
if (ret || !write)
return ret;
+ /*
+ * If throttling is disabled don't allow the write:
+ */
+ if (sysctl_perf_cpu_time_max_percent == 100 ||
+ sysctl_perf_cpu_time_max_percent == 0)
+ return -EINVAL;
+
max_samples_per_tick = DIV_ROUND_UP(sysctl_perf_event_sample_rate, HZ);
perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate;
update_perf_cpu_limits();
static void ring_buffer_attach(struct perf_event *event,
struct ring_buffer *rb);
+static void detach_sb_event(struct perf_event *event)
+{
+ struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu);
+
+ raw_spin_lock(&pel->lock);
+ list_del_rcu(&event->sb_list);
+ raw_spin_unlock(&pel->lock);
+}
+
+static bool is_sb_event(struct perf_event *event)
+{
+ struct perf_event_attr *attr = &event->attr;
+
+ if (event->parent)
+ return false;
+
+ if (event->attach_state & PERF_ATTACH_TASK)
+ return false;
+
+ if (attr->mmap || attr->mmap_data || attr->mmap2 ||
+ attr->comm || attr->comm_exec ||
+ attr->task ||
+ attr->context_switch)
+ return true;
+ return false;
+}
+
+static void unaccount_pmu_sb_event(struct perf_event *event)
+{
+ if (is_sb_event(event))
+ detach_sb_event(event);
+}
+
static void unaccount_event_cpu(struct perf_event *event, int cpu)
{
if (event->parent)
}
unaccount_event_cpu(event, event->cpu);
+
+ unaccount_pmu_sb_event(event);
}
static void perf_sched_delayed(struct work_struct *work)
perf_output_end(&handle);
}
-typedef void (perf_event_aux_output_cb)(struct perf_event *event, void *data);
+typedef void (perf_iterate_f)(struct perf_event *event, void *data);
static void
-perf_event_aux_ctx(struct perf_event_context *ctx,
- perf_event_aux_output_cb output,
+perf_iterate_ctx(struct perf_event_context *ctx,
+ perf_iterate_f output,
void *data, bool all)
{
struct perf_event *event;
}
}
-static void
-perf_event_aux_task_ctx(perf_event_aux_output_cb output, void *data,
- struct perf_event_context *task_ctx)
+static void perf_iterate_sb_cpu(perf_iterate_f output, void *data)
{
- rcu_read_lock();
- preempt_disable();
- perf_event_aux_ctx(task_ctx, output, data, false);
- preempt_enable();
- rcu_read_unlock();
+ struct pmu_event_list *pel = this_cpu_ptr(&pmu_sb_events);
+ struct perf_event *event;
+
+ list_for_each_entry_rcu(event, &pel->list, sb_list) {
+ if (event->state < PERF_EVENT_STATE_INACTIVE)
+ continue;
+ if (!event_filter_match(event))
+ continue;
+ output(event, data);
+ }
}
+/*
+ * Iterate all events that need to receive side-band events.
+ *
+ * For new callers; ensure that account_pmu_sb_event() includes
+ * your event, otherwise it might not get delivered.
+ */
static void
-perf_event_aux(perf_event_aux_output_cb output, void *data,
+perf_iterate_sb(perf_iterate_f output, void *data,
struct perf_event_context *task_ctx)
{
- struct perf_cpu_context *cpuctx;
struct perf_event_context *ctx;
- struct pmu *pmu;
int ctxn;
+ rcu_read_lock();
+ preempt_disable();
+
/*
- * If we have task_ctx != NULL we only notify
- * the task context itself. The task_ctx is set
- * only for EXIT events before releasing task
+ * If we have task_ctx != NULL we only notify the task context itself.
+ * The task_ctx is set only for EXIT events before releasing task
* context.
*/
if (task_ctx) {
- perf_event_aux_task_ctx(output, data, task_ctx);
- return;
+ perf_iterate_ctx(task_ctx, output, data, false);
+ goto done;
}
- rcu_read_lock();
- list_for_each_entry_rcu(pmu, &pmus, entry) {
- cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);
- if (cpuctx->unique_pmu != pmu)
- goto next;
- perf_event_aux_ctx(&cpuctx->ctx, output, data, false);
- ctxn = pmu->task_ctx_nr;
- if (ctxn < 0)
- goto next;
+ perf_iterate_sb_cpu(output, data);
+
+ for_each_task_context_nr(ctxn) {
ctx = rcu_dereference(current->perf_event_ctxp[ctxn]);
if (ctx)
- perf_event_aux_ctx(ctx, output, data, false);
-next:
- put_cpu_ptr(pmu->pmu_cpu_context);
+ perf_iterate_ctx(ctx, output, data, false);
}
+done:
+ preempt_enable();
rcu_read_unlock();
}
perf_event_enable_on_exec(ctxn);
- perf_event_aux_ctx(ctx, perf_event_addr_filters_exec, NULL,
+ perf_iterate_ctx(ctx, perf_event_addr_filters_exec, NULL,
true);
}
rcu_read_unlock();
};
rcu_read_lock();
- perf_event_aux_ctx(&cpuctx->ctx, __perf_event_output_stop, &ro, false);
+ perf_iterate_ctx(&cpuctx->ctx, __perf_event_output_stop, &ro, false);
if (cpuctx->task_ctx)
- perf_event_aux_ctx(cpuctx->task_ctx, __perf_event_output_stop,
+ perf_iterate_ctx(cpuctx->task_ctx, __perf_event_output_stop,
&ro, false);
rcu_read_unlock();
},
};
- perf_event_aux(perf_event_task_output,
+ perf_iterate_sb(perf_event_task_output,
&task_event,
task_ctx);
}
comm_event->event_id.header.size = sizeof(comm_event->event_id) + size;
- perf_event_aux(perf_event_comm_output,
+ perf_iterate_sb(perf_event_comm_output,
comm_event,
NULL);
}
mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size;
- perf_event_aux(perf_event_mmap_output,
+ perf_iterate_sb(perf_event_mmap_output,
mmap_event,
NULL);
if (!ctx)
continue;
- perf_event_aux_ctx(ctx, __perf_addr_filters_adjust, vma, true);
+ perf_iterate_ctx(ctx, __perf_addr_filters_adjust, vma, true);
}
rcu_read_unlock();
}
},
};
- perf_event_aux(perf_event_switch_output,
+ perf_iterate_sb(perf_event_switch_output,
&switch_event,
NULL);
}
return pmu;
}
+static void attach_sb_event(struct perf_event *event)
+{
+ struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu);
+
+ raw_spin_lock(&pel->lock);
+ list_add_rcu(&event->sb_list, &pel->list);
+ raw_spin_unlock(&pel->lock);
+}
+
+/*
+ * We keep a list of all !task (and therefore per-cpu) events
+ * that need to receive side-band records.
+ *
+ * This avoids having to scan all the various PMU per-cpu contexts
+ * looking for them.
+ */
+static void account_pmu_sb_event(struct perf_event *event)
+{
+ if (is_sb_event(event))
+ attach_sb_event(event);
+}
+
static void account_event_cpu(struct perf_event *event, int cpu)
{
if (event->parent)
enabled:
account_event_cpu(event, event->cpu);
+
+ account_pmu_sb_event(event);
}
/*
if (!event->parent) {
if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) {
- err = get_callchain_buffers();
+ err = get_callchain_buffers(attr->sample_max_stack);
if (err)
goto err_addr_filters;
}
return -EINVAL;
}
+ if (!attr.sample_max_stack)
+ attr.sample_max_stack = sysctl_perf_event_max_stack;
+
/*
* In cgroup mode, the pid argument is used to pass the fd
* opened to the cgroup directory in cgroupfs. The cpu argument
if (is_sampling_event(event)) {
if (event->pmu->capabilities & PERF_PMU_CAP_NO_INTERRUPT) {
- err = -ENOTSUPP;
+ err = -EOPNOTSUPP;
goto err_alloc;
}
}
swhash = &per_cpu(swevent_htable, cpu);
mutex_init(&swhash->hlist_mutex);
INIT_LIST_HEAD(&per_cpu(active_ctx_list, cpu));
+
+ INIT_LIST_HEAD(&per_cpu(pmu_sb_events.list, cpu));
+ raw_spin_lock_init(&per_cpu(pmu_sb_events.lock, cpu));
}
}