summaryrefslogtreecommitdiff
path: root/kernel/exit.c
diff options
context:
space:
mode:
authorOleg Nesterov <oleg@redhat.com>2010-05-26 14:43:11 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2010-05-27 09:12:46 -0700
commitd344193a05da89c97e965da2c5cbf687d7385eae (patch)
tree6267b68c31c4547f1749acd35d2a5bfaff919839 /kernel/exit.c
parent09faef11df8c559a23e2405d123cb2683733a79a (diff)
downloadlwn-d344193a05da89c97e965da2c5cbf687d7385eae.tar.gz
lwn-d344193a05da89c97e965da2c5cbf687d7385eae.zip
exit: avoid sig->count in de_thread/__exit_signal synchronization
de_thread() and __exit_signal() use signal_struct->count/notify_count for synchronization. We can simplify the code and use ->notify_count only. Instead of comparing these two counters, we can change de_thread() to set ->notify_count = nr_of_sub_threads, then change __exit_signal() to dec-and-test this counter and notify group_exit_task. Note that __exit_signal() checks "notify_count > 0" just for symmetry with exit_notify(), we could just check it is != 0. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Roland McGrath <roland@redhat.com> Cc: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel/exit.c')
-rw-r--r--kernel/exit.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/exit.c b/kernel/exit.c
index 59a104c673f7..9220967f4256 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -97,7 +97,7 @@ static void __exit_signal(struct task_struct *tsk)
* If there is any task waiting for the group exit
* then notify it:
*/
- if (sig->group_exit_task && atomic_read(&sig->count) == sig->notify_count)
+ if (sig->notify_count > 0 && !--sig->notify_count)
wake_up_process(sig->group_exit_task);
if (tsk == sig->curr_target)