diff options
| author | Konstantin Khlebnikov <khlebnikov@openvz.org> | 2012-05-31 16:26:21 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-05-31 17:49:29 -0700 |
| commit | f7505d64f2db5da2d7d94873ddf2cd2524847061 (patch) | |
| tree | a10aee9604306826816e8e5fc689201f49d7a6d0 | |
| parent | bca15543736f9be6d84e0bbc262ea7069076b9e6 (diff) | |
fork: call complete_vfork_done() after clearing child_tid and flushing rss-counters
Child should wake up the parent from vfork() only after finishing all
operations with shared mm. There is no sense in using
CLONE_CHILD_CLEARTID together with CLONE_VFORK, but it looks more accurate
now.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Markus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | kernel/fork.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/kernel/fork.c b/kernel/fork.c index 017fb23d598..2254fbf2356 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -787,9 +787,6 @@ void mm_release(struct task_struct *tsk, struct mm_struct *mm) /* Get rid of any cached register state */ deactivate_mm(tsk, mm); - if (tsk->vfork_done) - complete_vfork_done(tsk); - /* * If we're exiting normally, clear a user-space tid field if * requested. We leave this alone when dying by signal, to leave @@ -810,6 +807,13 @@ void mm_release(struct task_struct *tsk, struct mm_struct *mm) } tsk->clear_child_tid = NULL; } + + /* + * All done, finally we can wake up parent and return this mm to him. + * Also kthread_stop() uses this completion for synchronization. + */ + if (tsk->vfork_done) + complete_vfork_done(tsk); } /* |