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-rw-r--r--kernel/events/core.c22
1 files changed, 1 insertions, 21 deletions
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 98c862a..f1e53e8 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -3758,19 +3758,7 @@ int perf_event_release_kernel(struct perf_event *event)
if (!is_kernel_event(event))
perf_remove_from_owner(event);
- /*
- * There are two ways this annotation is useful:
- *
- * 1) there is a lock recursion from perf_event_exit_task
- * see the comment there.
- *
- * 2) there is a lock-inversion with mmap_sem through
- * perf_read_group(), which takes faults while
- * holding ctx->mutex, however this is called after
- * the last filedesc died, so there is no possibility
- * to trigger the AB-BA case.
- */
- ctx = perf_event_ctx_lock_nested(event, SINGLE_DEPTH_NESTING);
+ ctx = perf_event_ctx_lock(event);
WARN_ON_ONCE(ctx->parent_ctx);
perf_remove_from_context(event, DETACH_GROUP | DETACH_STATE);
perf_event_ctx_unlock(event, ctx);
@@ -8759,14 +8747,6 @@ static void perf_event_exit_task_context(struct task_struct *child, int ctxn)
* perf_event_create_kernel_count() which does find_get_context()
* without ctx::mutex (it cannot because of the move_group double mutex
* lock thing). See the comments in perf_install_in_context().
- *
- * We can recurse on the same lock type through:
- *
- * perf_event_exit_event()
- * put_event()
- * mutex_lock(&ctx->mutex)
- *
- * But since its the parent context it won't be the same instance.
*/
mutex_lock(&child_ctx->mutex);
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