summaryrefslogtreecommitdiff
path: root/kernel/sched.c
diff options
context:
space:
mode:
authorYong Zhang <yong.zhang0@gmail.com>2011-05-09 22:07:05 +0800
committerIngo Molnar <mingo@elte.hu>2011-05-16 11:01:18 +0200
commitdb44fc017d5989302713ab4e7f9e922b648f4b59 (patch)
treea6b8830b580fe5ebf7b0ff2f271c59173b15bc9b /kernel/sched.c
parent61eadef6a9bde9ea62fda724a9cb501ce9bc925a (diff)
sched: Avoid going ahead if ->cpus_allowed is not changed
If cpumask_equal(&p->cpus_allowed, new_mask) is true, seems there is no reason to prevent set_cpus_allowed_ptr() return directly. Signed-off-by: Yong Zhang <yong.zhang0@gmail.com> Acked-by: Hillf Danton <dhillf@gmail.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20110509140705.GA2219@zhy Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/sched.c')
-rw-r--r--kernel/sched.c6
1 files changed, 4 insertions, 2 deletions
diff --git a/kernel/sched.c b/kernel/sched.c
index b8b9a7dac9b0..70bec4f1edbb 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -5946,13 +5946,15 @@ int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
rq = task_rq_lock(p, &flags);
+ if (cpumask_equal(&p->cpus_allowed, new_mask))
+ goto out;
+
if (!cpumask_intersects(new_mask, cpu_active_mask)) {
ret = -EINVAL;
goto out;
}
- if (unlikely((p->flags & PF_THREAD_BOUND) && p != current &&
- !cpumask_equal(&p->cpus_allowed, new_mask))) {
+ if (unlikely((p->flags & PF_THREAD_BOUND) && p != current)) {
ret = -EINVAL;
goto out;
}