From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: mingo@elte.hu, efault@gmx.de
Cc: linux-kernel@vger.kernel.org, Peter Zijlstra <a.p.zijlstra@chello.nl>
Subject: [PATCH 2/3] sched: optimize update_curr()
Date: Tue, 16 Dec 2008 08:45:31 +0100 [thread overview]
Message-ID: <20081216074636.090411199@chello.nl> (raw)
In-Reply-To: 20081216074529.570706654@chello.nl
[-- Attachment #1: sched-opt-update_curr_fair.patch --]
[-- Type: text/plain, Size: 640 bytes --]
Skip the hard work when there is none.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Mike Galbraith <efault@gmx.de>
---
kernel/sched_fair.c | 2 ++
1 file changed, 2 insertions(+)
Index: linux-2.6/kernel/sched_fair.c
===================================================================
--- linux-2.6.orig/kernel/sched_fair.c
+++ linux-2.6/kernel/sched_fair.c
@@ -492,6 +492,8 @@ static void update_curr(struct cfs_rq *c
* overflow on 32 bits):
*/
delta_exec = (unsigned long)(now - curr->exec_start);
+ if (!delta_exec)
+ return;
__update_curr(cfs_rq, curr, delta_exec);
curr->exec_start = now;
--
next prev parent reply other threads:[~2008-12-16 7:48 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-12-16 7:45 [PATCH 0/3] scheduler patches Peter Zijlstra
2008-12-16 7:45 ` [PATCH 1/3] From: Mike Galbraith <efault@gmx.de> Peter Zijlstra
2008-12-16 7:54 ` Peter Zijlstra
2008-12-16 7:45 ` Peter Zijlstra [this message]
2008-12-16 7:45 ` [PATCH 3/3] sched: prefer wakers Peter Zijlstra
2008-12-16 9:05 ` Mike Galbraith
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