perf/core: Simplify perf_event_free_task()

We have ctx->event_list that contains all events; no need to
repeatedly iterate the group lists to find them all.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: fweisbec@gmail.com
Link: http://lkml.kernel.org/r/20170316125823.239678244@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/kernel/events/core.c b/kernel/events/core.c
index fc7c9a85944d65524facd1c60c8c5294b61f6156..5f21e5e09ba411c8585a169eda207a7c583a3398 100644 (file)
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -10426,21 +10426,11 @@ void perf_event_free_task(struct task_struct *task)
                WRITE_ONCE(ctx->task, TASK_TOMBSTONE);
                put_task_struct(task); /* cannot be last */
                raw_spin_unlock_irq(&ctx->lock);
-again:
-               list_for_each_entry_safe(event, tmp, &ctx->pinned_groups,
-                               group_entry)
-                       perf_free_event(event, ctx);
 
-               list_for_each_entry_safe(event, tmp, &ctx->flexible_groups,
-                               group_entry)
+               list_for_each_entry_safe(event, tmp, &ctx->event_list, event_entry)
                        perf_free_event(event, ctx);
 
-               if (!list_empty(&ctx->pinned_groups) ||
-                               !list_empty(&ctx->flexible_groups))
-                       goto again;
-
                mutex_unlock(&ctx->mutex);
-
                put_ctx(ctx);
        }
 }