From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F0378C433EF for ; Sat, 11 Sep 2021 01:19:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D1A066113A for ; Sat, 11 Sep 2021 01:19:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235138AbhIKBUe (ORCPT ); Fri, 10 Sep 2021 21:20:34 -0400 Received: from mga18.intel.com ([134.134.136.126]:21358 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234991AbhIKBUU (ORCPT ); Fri, 10 Sep 2021 21:20:20 -0400 X-IronPort-AV: E=McAfee;i="6200,9189,10103"; a="208325815" X-IronPort-AV: E=Sophos;i="5.85,284,1624345200"; d="scan'208";a="208325815" Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Sep 2021 18:19:07 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.85,284,1624345200"; d="scan'208";a="695261622" Received: from ranerica-svr.sc.intel.com ([172.25.110.23]) by fmsmga006.fm.intel.com with ESMTP; 10 Sep 2021 18:19:07 -0700 From: Ricardo Neri To: "Peter Zijlstra (Intel)" , Ingo Molnar , Juri Lelli , Vincent Guittot Cc: Srikar Dronamraju , Nicholas Piggin , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Len Brown , Srinivas Pandruvada , Tim Chen , Aubrey Li , "Ravi V. Shankar" , Ricardo Neri , Quentin Perret , "Joel Fernandes (Google)" , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, Ricardo Neri , Aubrey Li , Daniel Bristot de Oliveira , "Rafael J . Wysocki" Subject: [PATCH v5 2/6] sched/topology: Introduce sched_group::flags Date: Fri, 10 Sep 2021 18:18:15 -0700 Message-Id: <20210911011819.12184-3-ricardo.neri-calderon@linux.intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210911011819.12184-1-ricardo.neri-calderon@linux.intel.com> References: <20210911011819.12184-1-ricardo.neri-calderon@linux.intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org There exist situations in which the load balance needs to know the properties of the CPUs in a scheduling group. When using asymmetric packing, for instance, the load balancer needs to know not only the state of dst_cpu but also of its SMT siblings, if any. Use the flags of the child scheduling domains to initialize scheduling group flags. This will reflect the properties of the CPUs in the group. A subsequent changeset will make use of these new flags. No functional changes are introduced. Cc: Aubrey Li Cc: Ben Segall Cc: Daniel Bristot de Oliveira Cc: Dietmar Eggemann Cc: Mel Gorman Cc: Quentin Perret Cc: Rafael J. Wysocki Cc: Srinivas Pandruvada Cc: Steven Rostedt Cc: Tim Chen Reviewed-by: Joel Fernandes (Google) Reviewed-by: Len Brown Originally-by: Peter Zijlstra (Intel) Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Ricardo Neri --- Changes since v4: * None Changes since v3: * Clear the flags of the scheduling groups of a domain if its child is destroyed. * Minor rewording of the commit message. Changes since v2: * Introduced this patch. Changes since v1: * N/A --- kernel/sched/sched.h | 1 + kernel/sched/topology.c | 21 ++++++++++++++++++--- 2 files changed, 19 insertions(+), 3 deletions(-) diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 3d3e5793e117..86ab33ce529d 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -1809,6 +1809,7 @@ struct sched_group { unsigned int group_weight; struct sched_group_capacity *sgc; int asym_prefer_cpu; /* CPU of highest priority in group */ + int flags; /* * The CPUs this group covers. diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c index 4e8698e62f07..c56faae461d9 100644 --- a/kernel/sched/topology.c +++ b/kernel/sched/topology.c @@ -716,8 +716,20 @@ cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu) tmp = sd; sd = sd->parent; destroy_sched_domain(tmp); - if (sd) + if (sd) { + struct sched_group *sg = sd->groups; + + /* + * sched groups hold the flags of the child sched + * domain for convenience. Clear such flags since + * the child is being destroyed. + */ + do { + sg->flags = 0; + } while (sg != sd->groups); + sd->child = NULL; + } } for (tmp = sd; tmp; tmp = tmp->parent) @@ -916,10 +928,12 @@ build_group_from_child_sched_domain(struct sched_domain *sd, int cpu) return NULL; sg_span = sched_group_span(sg); - if (sd->child) + if (sd->child) { cpumask_copy(sg_span, sched_domain_span(sd->child)); - else + sg->flags = sd->child->flags; + } else { cpumask_copy(sg_span, sched_domain_span(sd)); + } atomic_inc(&sg->ref); return sg; @@ -1169,6 +1183,7 @@ static struct sched_group *get_group(int cpu, struct sd_data *sdd) if (child) { cpumask_copy(sched_group_span(sg), sched_domain_span(child)); cpumask_copy(group_balance_mask(sg), sched_group_span(sg)); + sg->flags = child->flags; } else { cpumask_set_cpu(cpu, sched_group_span(sg)); cpumask_set_cpu(cpu, group_balance_mask(sg)); -- 2.17.1