diff options
Diffstat (limited to 'kernel/events')
| -rw-r--r-- | kernel/events/core.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/kernel/events/core.c b/kernel/events/core.c index 0940c8810be0..f48d38b55e7b 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -3204,10 +3204,21 @@ static void perf_event_context_sched_out(struct task_struct *task, int ctxn, raw_spin_lock(&ctx->lock); raw_spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING); if (context_equiv(ctx, next_ctx)) { + struct pmu *pmu = ctx->pmu; + WRITE_ONCE(ctx->task, next); WRITE_ONCE(next_ctx->task, task); - swap(ctx->task_ctx_data, next_ctx->task_ctx_data); + /* + * PMU specific parts of task perf context can require + * additional synchronization. As an example of such + * synchronization see implementation details of Intel + * LBR call stack data profiling; + */ + if (pmu->swap_task_ctx) + pmu->swap_task_ctx(ctx, next_ctx); + else + swap(ctx->task_ctx_data, next_ctx->task_ctx_data); /* * RCU_INIT_POINTER here is safe because we've not |