From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758940Ab3AQFsc (ORCPT ); Thu, 17 Jan 2013 00:48:32 -0500 Received: from e23smtp02.au.ibm.com ([202.81.31.144]:58451 "EHLO e23smtp02.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750905Ab3AQFsb (ORCPT ); Thu, 17 Jan 2013 00:48:31 -0500 Message-ID: <50F790A5.10107@linux.vnet.ibm.com> Date: Thu, 17 Jan 2013 13:48:21 +0800 From: Michael Wang User-Agent: Mozilla/5.0 (X11; Linux i686; rv:16.0) Gecko/20121011 Thunderbird/16.0.1 MIME-Version: 1.0 To: LKML CC: Ingo Molnar , Peter Zijlstra , Paul Turner , Mike Galbraith , Andrew Morton , Tejun Heo , "Nikunj A. Dadhania" , Namhyung Kim , Ram Pai Subject: [RFC PATCH v2 2/3] sched: build schedule balance map References: <50F79047.1080907@linux.vnet.ibm.com> In-Reply-To: <50F79047.1080907@linux.vnet.ibm.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13011705-5490-0000-0000-000002D28DE2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch will build schedule balance map as designed, now cpu_sbm->sd[f][l] can directly locate the sd of cpu on level 'l' with flag 'f' supported. In order to quickly locate the lower sd while changing the base cpu, the level with empty sd in map will be filled with the lower sd. Signed-off-by: Michael Wang --- kernel/sched/core.c | 70 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 70 insertions(+), 0 deletions(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 092c801..0c63303 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -5578,6 +5578,62 @@ static void update_top_cache_domain(int cpu) static int sbm_max_level; DEFINE_PER_CPU_SHARED_ALIGNED(struct sched_balance_map, sbm_array); +static void build_sched_balance_map(int cpu) +{ + struct sched_balance_map *sbm = &per_cpu(sbm_array, cpu); + struct sched_domain *sd = cpu_rq(cpu)->sd; + struct sched_domain *top_sd = NULL; + int i, type, level = 0; + + memset(sbm->top_level, 0, sizeof((*sbm).top_level)); + memset(sbm->affine_map, 0, sizeof((*sbm).affine_map)); + for (type = 0; type < SBM_MAX_TYPE; type++) { + memset(sbm->sd[type], 0, + sizeof(struct sched_domain *) * sbm_max_level); + } + + while (sd) { + if (!(sd->flags & SD_LOAD_BALANCE)) + continue; + + if (sd->flags & SD_BALANCE_EXEC) { + sbm->top_level[SBM_EXEC_TYPE] = sd->level; + sbm->sd[SBM_EXEC_TYPE][sd->level] = sd; + } + + if (sd->flags & SD_BALANCE_FORK) { + sbm->top_level[SBM_FORK_TYPE] = sd->level; + sbm->sd[SBM_FORK_TYPE][sd->level] = sd; + } + + if (sd->flags & SD_BALANCE_WAKE) { + sbm->top_level[SBM_WAKE_TYPE] = sd->level; + sbm->sd[SBM_WAKE_TYPE][sd->level] = sd; + } + + if (sd->flags & SD_WAKE_AFFINE) { + for_each_cpu(i, sched_domain_span(sd)) { + if (!sbm->affine_map[i]) + sbm->affine_map[i] = sd; + } + } + + sd = sd->parent; + } + + /* + * fill the hole to get lower level sd easily. + */ + for (type = 0; type < SBM_MAX_TYPE; type++) { + level = sbm->top_level[type]; + top_sd = sbm->sd[type][level]; + if ((++level != sbm_max_level) && top_sd) { + for (; level < sbm_max_level; level++) + sbm->sd[type][level] = top_sd; + } + } +} + /* * Attach the domain 'sd' to 'cpu' as its base domain. Callers must * hold the hotplug lock. @@ -5587,6 +5643,9 @@ cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu) { struct rq *rq = cpu_rq(cpu); struct sched_domain *tmp; + struct sched_balance_map *sbm = &per_cpu(sbm_array, cpu); + + rcu_assign_pointer(rq->sbm, NULL); /* Remove the sched domains which do not contribute to scheduling. */ for (tmp = sd; tmp; ) { @@ -5619,6 +5678,17 @@ cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu) destroy_sched_domains(tmp, cpu); update_top_cache_domain(cpu); + + /* disable sbm if initialization failed or sd detached. */ + if (!sbm_max_level || !sd) + return; + + /* + * synchronize_rcu() is unnecessary here since + * destroy_sched_domains() already do the work. + */ + build_sched_balance_map(cpu); + rcu_assign_pointer(rq->sbm, sbm); } /* cpus with isolated domains */ -- 1.7.4.1