path: root/kernel/sched_autogroup.c
diff options
authorYong Zhang <yong.zhang0@gmail.com>2011-02-20 15:08:14 +0800
committerIngo Molnar <mingo@elte.hu>2011-02-23 11:33:59 +0100
commit800d4d30c8f20bd728e5741a3b77c4859a613f7c (patch)
tree1eb329fb8a1dce1c1432c07e19494a3e1fb68499 /kernel/sched_autogroup.c
parent1747b21fecbfb63fbf6b9624e8b92707960d5a97 (diff)
sched, autogroup: Stop going ahead if autogroup is disabled
when autogroup is disable from the beginning, sched_autogroup_create_attach() autogroup_move_group() <== 1 sched_move_task() <== 2 task_move_group_fair() set_task_rq() task_group() autogroup_task_group() We go the whole path without doing anything useful. Then stop going further if autogroup is disabled. But there will be a race window between 1 and 2, in which sysctl_sched_autogroup_enabled is enabled. This issue will be toke by following patch. Signed-off-by: Yong Zhang <yong.zhang0@gmail.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <1298185696-4403-4-git-send-email-yong.zhang0@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/sched_autogroup.c')
1 files changed, 4 insertions, 0 deletions
diff --git a/kernel/sched_autogroup.c b/kernel/sched_autogroup.c
index 9fb65628315..137a096ae9d 100644
--- a/kernel/sched_autogroup.c
+++ b/kernel/sched_autogroup.c
@@ -161,11 +161,15 @@ autogroup_move_group(struct task_struct *p, struct autogroup *ag)
p->signal->autogroup = autogroup_kref_get(ag);
+ if (!ACCESS_ONCE(sysctl_sched_autogroup_enabled))
+ goto out;
t = p;
do {
} while_each_thread(p, t);
unlock_task_sighand(p, &flags);