From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757515Ab0JRTXd (ORCPT ); Mon, 18 Oct 2010 15:23:33 -0400 Received: from hera.kernel.org ([140.211.167.34]:35183 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755879Ab0JRTXc (ORCPT ); Mon, 18 Oct 2010 15:23:32 -0400 Date: Mon, 18 Oct 2010 19:23:02 GMT From: tip-bot for Nikhil Rao Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@redhat.com, a.p.zijlstra@chello.nl, ncrao@google.com, tglx@linutronix.de, mingo@elte.hu Reply-To: mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, ncrao@google.com, a.p.zijlstra@chello.nl, tglx@linutronix.de, mingo@elte.hu In-Reply-To: <1287173550-30365-2-git-send-email-ncrao@google.com> References: <1287173550-30365-2-git-send-email-ncrao@google.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:sched/core] sched: Do not consider SCHED_IDLE tasks to be cache hot Message-ID: Git-Commit-ID: ef8002f6848236de5adc613063ebeabddea8a6fb X-Mailer: tip-git-log-daemon MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.3 (hera.kernel.org [127.0.0.1]); Mon, 18 Oct 2010 19:23:03 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: ef8002f6848236de5adc613063ebeabddea8a6fb Gitweb: http://git.kernel.org/tip/ef8002f6848236de5adc613063ebeabddea8a6fb Author: Nikhil Rao AuthorDate: Wed, 13 Oct 2010 12:09:35 -0700 Committer: Ingo Molnar CommitDate: Mon, 18 Oct 2010 20:52:15 +0200 sched: Do not consider SCHED_IDLE tasks to be cache hot This patch adds a check in task_hot to return if the task has SCHED_IDLE policy. SCHED_IDLE tasks have very low weight, and when run with regular workloads, are typically scheduled many milliseconds apart. There is no need to consider these tasks hot for load balancing. Signed-off-by: Nikhil Rao Signed-off-by: Peter Zijlstra LKML-Reference: <1287173550-30365-2-git-send-email-ncrao@google.com> Signed-off-by: Ingo Molnar --- kernel/sched.c | 3 +++ 1 files changed, 3 insertions(+), 0 deletions(-) diff --git a/kernel/sched.c b/kernel/sched.c index 728081a..771b518 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -2025,6 +2025,9 @@ task_hot(struct task_struct *p, u64 now, struct sched_domain *sd) if (p->sched_class != &fair_sched_class) return 0; + if (unlikely(p->policy == SCHED_IDLE)) + return 0; + /* * Buddy candidates are cache hot: */