summaryrefslogtreecommitdiff
path: root/kernel
diff options
context:
space:
mode:
authorstable-bot for Steven Rostedt <srostedt@redhat.com>2011-02-10 10:21:08 +0100
committerGreg Kroah-Hartman <gregkh@suse.de>2011-02-17 15:37:21 -0800
commitf1d703449a981bb481fe31f37782e96d6098eaf4 (patch)
treeacf6c13ed686f6faf26a8d543f38614422b6a936 /kernel
parentf266611ef30837a9bff442e905c1a72eca218cef (diff)
sched: Give CPU bound RT tasks preference
From:: Steven Rostedt <srostedt@redhat.com> Commit: b3bc211cfe7d5fe94b310480d78e00bea96fbf2a upstream If a high priority task is waking up on a CPU that is running a lower priority task that is bound to a CPU, see if we can move the high RT task to another CPU first. Note, if all other CPUs are running higher priority tasks than the CPU bounded current task, then it will be preempted regardless. Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Gregory Haskins <ghaskins@novell.com> LKML-Reference: <20100921024138.888922071@goodmis.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Mike Galbraith <efault@gmx.de> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'kernel')
-rw-r--r--kernel/sched_rt.c8
1 files changed, 5 insertions, 3 deletions
diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c
index d2d481f53040..3782369ed6f5 100644
--- a/kernel/sched_rt.c
+++ b/kernel/sched_rt.c
@@ -965,7 +965,8 @@ select_task_rq_rt(struct rq *rq, struct task_struct *p, int sd_flag, int flags)
* For equal prio tasks, we just let the scheduler sort it out.
*/
if (unlikely(rt_task(rq->curr)) &&
- rq->curr->prio < p->prio &&
+ (rq->curr->rt.nr_cpus_allowed < 2 ||
+ rq->curr->prio < p->prio) &&
(p->rt.nr_cpus_allowed > 1)) {
int cpu = find_lowest_rq(p);
@@ -1493,9 +1494,10 @@ static void task_woken_rt(struct rq *rq, struct task_struct *p)
if (!task_running(rq, p) &&
!test_tsk_need_resched(rq->curr) &&
has_pushable_tasks(rq) &&
+ p->rt.nr_cpus_allowed > 1 &&
rt_task(rq->curr) &&
- rq->curr->prio < p->prio &&
- p->rt.nr_cpus_allowed > 1)
+ (rq->curr->rt.nr_cpus_allowed < 2 ||
+ rq->curr->prio < p->prio))
push_rt_tasks(rq);
}