[PATCH] coredump_wait() cleanup
This patch deletes pointless code from coredump_wait().
1. It does useless mm->core_waiters inc/dec under mm->mmap_sem,
but any changes to ->core_waiters have no effect until we drop
->mmap_sem.
2. It calls yield() for absolutely unknown reason.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/exec.c b/fs/exec.c
index fc02dad..6d95216 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1417,19 +1417,16 @@
static void coredump_wait(struct mm_struct *mm)
{
DECLARE_COMPLETION(startup_done);
+ int core_waiters;
- mm->core_waiters++; /* let other threads block */
mm->core_startup_done = &startup_done;
- /* give other threads a chance to run: */
- yield();
-
zap_threads(mm);
- if (--mm->core_waiters) {
- up_write(&mm->mmap_sem);
+ core_waiters = mm->core_waiters;
+ up_write(&mm->mmap_sem);
+
+ if (core_waiters)
wait_for_completion(&startup_done);
- } else
- up_write(&mm->mmap_sem);
BUG_ON(mm->core_waiters);
}