From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756068AbdJJLET (ORCPT ); Tue, 10 Oct 2017 07:04:19 -0400 Received: from terminus.zytor.com ([65.50.211.136]:45497 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755998AbdJJLEO (ORCPT ); Tue, 10 Oct 2017 07:04:14 -0400 Date: Tue, 10 Oct 2017 03:59:30 -0700 From: tip-bot for Brendan Jackman Message-ID: Cc: vincent.guittot@linaro.org, jbacik@fb.com, tglx@linutronix.de, efault@gmx.de, hpa@zytor.com, dietmar.eggemann@arm.com, mingo@kernel.org, linux-kernel@vger.kernel.org, morten.rasmussen@arm.com, torvalds@linux-foundation.org, josef@toxicpanda.com, brendan.jackman@arm.com, peterz@infradead.org Reply-To: josef@toxicpanda.com, brendan.jackman@arm.com, peterz@infradead.org, hpa@zytor.com, dietmar.eggemann@arm.com, linux-kernel@vger.kernel.org, torvalds@linux-foundation.org, morten.rasmussen@arm.com, mingo@kernel.org, efault@gmx.de, jbacik@fb.com, vincent.guittot@linaro.org, tglx@linutronix.de In-Reply-To: <20171005114516.18617-2-brendan.jackman@arm.com> References: <20171005114516.18617-2-brendan.jackman@arm.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:sched/core] sched/fair: Move select_task_rq_fair() slow-path into its own function Git-Commit-ID: 18bd1b4bd53aba81d76d55e91a68310a227dc187 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 18bd1b4bd53aba81d76d55e91a68310a227dc187 Gitweb: https://git.kernel.org/tip/18bd1b4bd53aba81d76d55e91a68310a227dc187 Author: Brendan Jackman AuthorDate: Thu, 5 Oct 2017 12:45:12 +0100 Committer: Ingo Molnar CommitDate: Tue, 10 Oct 2017 11:45:33 +0200 sched/fair: Move select_task_rq_fair() slow-path into its own function In preparation for changes that would otherwise require adding a new level of indentation to the while(sd) loop, create a new function find_idlest_cpu() which contains this loop, and rename the existing find_idlest_cpu() to find_idlest_group_cpu(). Code inside the while(sd) loop is unchanged. @new_cpu is added as a variable in the new function, with the same initial value as the @new_cpu in select_task_rq_fair(). Suggested-by: Peter Zijlstra Signed-off-by: Brendan Jackman Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Josef Bacik Reviewed-by: Vincent Guittot Cc: Dietmar Eggemann Cc: Josef Bacik Cc: Linus Torvalds Cc: Mike Galbraith Cc: Morten Rasmussen Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/20171005114516.18617-2-brendan.jackman@arm.com Signed-off-by: Ingo Molnar --- kernel/sched/fair.c | 83 +++++++++++++++++++++++++++++++---------------------- 1 file changed, 48 insertions(+), 35 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index cf3e816..dd4f253 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -5859,10 +5859,10 @@ skip_spare: } /* - * find_idlest_cpu - find the idlest cpu among the cpus in group. + * find_idlest_group_cpu - find the idlest cpu among the cpus in group. */ static int -find_idlest_cpu(struct sched_group *group, struct task_struct *p, int this_cpu) +find_idlest_group_cpu(struct sched_group *group, struct task_struct *p, int this_cpu) { unsigned long load, min_load = ULONG_MAX; unsigned int min_exit_latency = UINT_MAX; @@ -5911,6 +5911,50 @@ find_idlest_cpu(struct sched_group *group, struct task_struct *p, int this_cpu) return shallowest_idle_cpu != -1 ? shallowest_idle_cpu : least_loaded_cpu; } +static inline int find_idlest_cpu(struct sched_domain *sd, struct task_struct *p, + int cpu, int prev_cpu, int sd_flag) +{ + int new_cpu = prev_cpu; + + while (sd) { + struct sched_group *group; + struct sched_domain *tmp; + int weight; + + if (!(sd->flags & sd_flag)) { + sd = sd->child; + continue; + } + + group = find_idlest_group(sd, p, cpu, sd_flag); + if (!group) { + sd = sd->child; + continue; + } + + new_cpu = find_idlest_group_cpu(group, p, cpu); + if (new_cpu == -1 || new_cpu == cpu) { + /* Now try balancing at a lower domain level of cpu */ + sd = sd->child; + continue; + } + + /* Now try balancing at a lower domain level of new_cpu */ + cpu = new_cpu; + weight = sd->span_weight; + sd = NULL; + for_each_domain(cpu, tmp) { + if (weight <= tmp->span_weight) + break; + if (tmp->flags & sd_flag) + sd = tmp; + } + /* while loop will break here if sd == NULL */ + } + + return new_cpu; +} + #ifdef CONFIG_SCHED_SMT static inline void set_idle_cores(int cpu, int val) @@ -6277,39 +6321,8 @@ pick_cpu: if (sd_flag & SD_BALANCE_WAKE) /* XXX always ? */ new_cpu = select_idle_sibling(p, prev_cpu, new_cpu); - } else while (sd) { - struct sched_group *group; - int weight; - - if (!(sd->flags & sd_flag)) { - sd = sd->child; - continue; - } - - group = find_idlest_group(sd, p, cpu, sd_flag); - if (!group) { - sd = sd->child; - continue; - } - - new_cpu = find_idlest_cpu(group, p, cpu); - if (new_cpu == -1 || new_cpu == cpu) { - /* Now try balancing at a lower domain level of cpu */ - sd = sd->child; - continue; - } - - /* Now try balancing at a lower domain level of new_cpu */ - cpu = new_cpu; - weight = sd->span_weight; - sd = NULL; - for_each_domain(cpu, tmp) { - if (weight <= tmp->span_weight) - break; - if (tmp->flags & sd_flag) - sd = tmp; - } - /* while loop will break here if sd == NULL */ + } else { + new_cpu = find_idlest_cpu(sd, p, cpu, prev_cpu, sd_flag); } rcu_read_unlock();