From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756722AbZIDIzh (ORCPT ); Fri, 4 Sep 2009 04:55:37 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756675AbZIDIze (ORCPT ); Fri, 4 Sep 2009 04:55:34 -0400 Received: from hera.kernel.org ([140.211.167.34]:36580 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753051AbZIDIzd (ORCPT ); Fri, 4 Sep 2009 04:55:33 -0400 Date: Fri, 4 Sep 2009 08:54:58 GMT From: tip-bot for Peter Zijlstra Cc: linux-kernel@vger.kernel.org, ego@in.ibm.com, hpa@zytor.com, mingo@redhat.com, andreas.herrmann3@amd.com, a.p.zijlstra@chello.nl, balbir@in.ibm.com, tglx@linutronix.de, mingo@elte.hu Reply-To: balbir@in.ibm.com, mingo@redhat.com, hpa@zytor.com, ego@in.ibm.com, linux-kernel@vger.kernel.org, a.p.zijlstra@chello.nl, andreas.herrmann3@amd.com, tglx@linutronix.de, mingo@elte.hu In-Reply-To: <20090901083825.810860576@chello.nl> References: <20090901083825.810860576@chello.nl> To: linux-tip-commits@vger.kernel.org Subject: [tip:sched/balancing] sched: Restore __cpu_power to a straight sum of power Message-ID: Git-Commit-ID: f93e65c186ab3c05ce2068733ca10e34fd00125e 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-4.0 (hera.kernel.org [127.0.0.1]); Fri, 04 Sep 2009 08:54:59 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: f93e65c186ab3c05ce2068733ca10e34fd00125e Gitweb: http://git.kernel.org/tip/f93e65c186ab3c05ce2068733ca10e34fd00125e Author: Peter Zijlstra AuthorDate: Tue, 1 Sep 2009 10:34:32 +0200 Committer: Ingo Molnar CommitDate: Fri, 4 Sep 2009 10:09:53 +0200 sched: Restore __cpu_power to a straight sum of power cpu_power is supposed to be a representation of the process capacity of the cpu, not a value to randomly tweak in order to affect placement. Remove the placement hacks. Signed-off-by: Peter Zijlstra Tested-by: Andreas Herrmann Acked-by: Andreas Herrmann Acked-by: Gautham R Shenoy Cc: Balbir Singh LKML-Reference: <20090901083825.810860576@chello.nl> Signed-off-by: Ingo Molnar --- kernel/sched.c | 28 ++++++++++++---------------- 1 files changed, 12 insertions(+), 16 deletions(-) diff --git a/kernel/sched.c b/kernel/sched.c index da1edc8..584a122 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -8464,15 +8464,13 @@ static void free_sched_groups(const struct cpumask *cpu_map, * there are asymmetries in the topology. If there are asymmetries, group * having more cpu_power will pickup more load compared to the group having * less cpu_power. - * - * cpu_power will be a multiple of SCHED_LOAD_SCALE. This multiple represents - * the maximum number of tasks a group can handle in the presence of other idle - * or lightly loaded groups in the same sched domain. */ static void init_sched_groups_power(int cpu, struct sched_domain *sd) { struct sched_domain *child; struct sched_group *group; + long power; + int weight; WARN_ON(!sd || !sd->groups); @@ -8483,22 +8481,20 @@ static void init_sched_groups_power(int cpu, struct sched_domain *sd) sd->groups->__cpu_power = 0; - /* - * For perf policy, if the groups in child domain share resources - * (for example cores sharing some portions of the cache hierarchy - * or SMT), then set this domain groups cpu_power such that each group - * can handle only one task, when there are other idle groups in the - * same sched domain. - */ - if (!child || (!(sd->flags & SD_POWERSAVINGS_BALANCE) && - (child->flags & - (SD_SHARE_CPUPOWER | SD_SHARE_PKG_RESOURCES)))) { - sg_inc_cpu_power(sd->groups, SCHED_LOAD_SCALE); + if (!child) { + power = SCHED_LOAD_SCALE; + weight = cpumask_weight(sched_domain_span(sd)); + /* + * SMT siblings share the power of a single core. + */ + if ((sd->flags & SD_SHARE_CPUPOWER) && weight > 1) + power /= weight; + sg_inc_cpu_power(sd->groups, power); return; } /* - * add cpu_power of each child group to this groups cpu_power + * Add cpu_power of each child group to this groups cpu_power. */ group = child->groups; do {