Re: [PATCH] cgroup, cleanup: Delete PF_EXITING checks from cgroup_exit() callbacks

[Peter Zijlstra <peterz@infradead.org>]

I made that two patches, like:

---
Subject: perf: Delete PF_EXITING checks from perf_cgroup_exit() callback
From: Kirill Tkhai <ktkhai@odin.com>
Date: Mon, 31 Aug 2015 15:12:56 +0300

cgroup_exit() is not called from copy_process() after commit:

  e8604cb43690 ("cgroup: fix spurious lockdep warning in cgroup_exit()")

from do_exit(). So this check is useless and the comment is obsolete.

Signed-off-by: Kirill Tkhai <ktkhai@odin.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/55E444C8.3020402@odin.com
---
 kernel/events/core.c |    8 --------
 1 file changed, 8 deletions(-)

--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -9219,14 +9219,6 @@ static void perf_cgroup_exit(struct cgro
 			     struct cgroup_subsys_state *old_css,
 			     struct task_struct *task)
 {
-	/*
-	 * cgroup_exit() is called in the copy_process() failure path.
-	 * Ignore this case since the task hasn't ran yet, this avoids
-	 * trying to poke a half freed task state from generic code.
-	 */
-	if (!(task->flags & PF_EXITING))
-		return;
-
 	task_function_call(task, __perf_cgroup_move, task);
 }