From 558abc7e3f895049faa46b08656be4c60dc6e9fd Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 7 Aug 2024 13:29:27 +0200 Subject: [PATCH] perf: Fix event_function_call() locking All the event_function/@func call context already uses perf_ctx_lock() except for the !ctx->is_active case. Make it all consistent. Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Kan Liang Reviewed-by: Namhyung Kim Link: https://lore.kernel.org/r/20240807115550.138301094@infradead.org --- kernel/events/core.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index eb03c9ab16700..ab49deae6e6f3 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -263,6 +263,7 @@ unlock: static void event_function_call(struct perf_event *event, event_f func, void *data) { struct perf_event_context *ctx = event->ctx; + struct perf_cpu_context *cpuctx = this_cpu_ptr(&perf_cpu_context); struct task_struct *task = READ_ONCE(ctx->task); /* verified in event_function */ struct event_function_struct efs = { .event = event, @@ -291,22 +292,22 @@ again: if (!task_function_call(task, event_function, &efs)) return; - raw_spin_lock_irq(&ctx->lock); + perf_ctx_lock(cpuctx, ctx); /* * Reload the task pointer, it might have been changed by * a concurrent perf_event_context_sched_out(). */ task = ctx->task; if (task == TASK_TOMBSTONE) { - raw_spin_unlock_irq(&ctx->lock); + perf_ctx_unlock(cpuctx, ctx); return; } if (ctx->is_active) { - raw_spin_unlock_irq(&ctx->lock); + perf_ctx_unlock(cpuctx, ctx); goto again; } func(event, NULL, ctx, data); - raw_spin_unlock_irq(&ctx->lock); + perf_ctx_unlock(cpuctx, ctx); } /* -- 2.39.5