diff options
| -rw-r--r-- | kernel/events/core.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/kernel/events/core.c b/kernel/events/core.c index f48d38b55e7b..ea70ca614987 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -2666,6 +2666,25 @@ perf_install_in_context(struct perf_event_context *ctx, */ smp_store_release(&event->ctx, ctx); + /* + * perf_event_attr::disabled events will not run and can be initialized + * without IPI. Except when this is the first event for the context, in + * that case we need the magic of the IPI to set ctx->is_active. + * + * The IOC_ENABLE that is sure to follow the creation of a disabled + * event will issue the IPI and reprogram the hardware. + */ + if (__perf_effective_state(event) == PERF_EVENT_STATE_OFF && ctx->nr_events) { + raw_spin_lock_irq(&ctx->lock); + if (ctx->task == TASK_TOMBSTONE) { + raw_spin_unlock_irq(&ctx->lock); + return; + } + add_event_to_ctx(event, ctx); + raw_spin_unlock_irq(&ctx->lock); + return; + } + if (!task) { cpu_function_call(cpu, __perf_install_in_context, event); return; |