[RFC][PATCH 01/10] sched: Change rt_task(prev) in pre_schedule_rt to likely

Steven Rostedt
2010-12-07T02:15:27Z

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From: Steven Rostedt <srostedt@redhat.com>

As found with the branch annotation profiler, the unlikely(rt_task(prev))
in pre_schedule_rt() is always wrong. In fact it should be likely due to
the fact that we got to this function because we used prev's scheduling
class (which had to be rt).

Change the unlikely(rt_task(prev)) to likely(rt_task(prev))

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Gregory Haskins <ghaskins@novell.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
kernel/sched_rt.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c
index bea7d79..7a5c4db 100644
--- a/kernel/sched_rt.c
+++ b/kernel/sched_rt.c
@@ -1474,7 +1474,7 @@ skip:
static void pre_schedule_rt(struct rq *rq, struct task_struct *prev)
{
/* Try to pull RT tasks here if we lower this rq's prio */
- if (unlikely(rt_task(prev)) && rq->rt.highest_prio.curr > prev->prio)
+ if (likely(rt_task(prev)) && rq->rt.highest_prio.curr > prev->prio)
pull_rt_task(rq);
}

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1.7.2.3