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=-13.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 02DE8C433E0 for ; Fri, 31 Jul 2020 12:05:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D13E120663 for ; Fri, 31 Jul 2020 12:05:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733087AbgGaMFR (ORCPT ); Fri, 31 Jul 2020 08:05:17 -0400 Received: from foss.arm.com ([217.140.110.172]:56238 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732965AbgGaMFN (ORCPT ); Fri, 31 Jul 2020 08:05:13 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 39A66106F; Fri, 31 Jul 2020 05:05:13 -0700 (PDT) Received: from e113632-lin.cambridge.arm.com (e113632-lin.cambridge.arm.com [10.1.194.46]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 173113F71F; Fri, 31 Jul 2020 05:05:11 -0700 (PDT) From: Valentin Schneider To: linux-kernel@vger.kernel.org Cc: mingo@kernel.org, peterz@infradead.org, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, morten.rasmussen@arm.com, Quentin Perret Subject: [PATCH v4 07/10] sched/topology: Add more flags to the SD degeneration mask Date: Fri, 31 Jul 2020 12:54:59 +0100 Message-Id: <20200731115502.12954-8-valentin.schneider@arm.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200731115502.12954-1-valentin.schneider@arm.com> References: <20200731115502.12954-1-valentin.schneider@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org I don't think it is going to change much in practice, but we were missing those: o SD_BALANCE_WAKE: Used just like the other SD_BALANCE_* flags, so also needs > 1 group. o SD_ASYM_PACKING: Hinges on load balancing (periodic / wakeup), thus needs > 1 group to happen o SD_OVERLAP: Describes domains with overlapping groups; can't have overlaps with a single group. SD_PREFER_SIBLING is as always the odd one out: we currently consider it in sd_parent_degenerate() but not in sd_degenerate(). It too hinges on load balancing, and thus won't have any effect when set on a domain with a single group. Add it to the sd_degenerate() groups mask. Signed-off-by: Valentin Schneider --- kernel/sched/topology.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c index cda02507aebf..93a7ff52335b 100644 --- a/kernel/sched/topology.c +++ b/kernel/sched/topology.c @@ -161,11 +161,15 @@ static int sd_degenerate(struct sched_domain *sd) /* Following flags need at least 2 groups */ if (sd->flags & (SD_BALANCE_NEWIDLE | + SD_BALANCE_WAKE | SD_BALANCE_FORK | SD_BALANCE_EXEC | + SD_ASYM_PACKING | SD_SHARE_CPUCAPACITY | SD_ASYM_CPUCAPACITY | - SD_SHARE_PKG_RESOURCES)) { + SD_SHARE_PKG_RESOURCES | + SD_OVERLAP | + SD_PREFER_SIBLING)) { if (sd->groups != sd->groups->next) return 0; } @@ -191,11 +195,14 @@ sd_parent_degenerate(struct sched_domain *sd, struct sched_domain *parent) /* Flags needing groups don't count if only 1 group in parent */ if (parent->groups == parent->groups->next) { pflags &= ~(SD_BALANCE_NEWIDLE | + SD_BALANCE_WAKE | SD_BALANCE_FORK | SD_BALANCE_EXEC | + SD_ASYM_PACKING | SD_ASYM_CPUCAPACITY | SD_SHARE_CPUCAPACITY | SD_SHARE_PKG_RESOURCES | + SD_OVERLAP | SD_PREFER_SIBLING); if (nr_node_ids == 1) pflags &= ~SD_SERIALIZE; -- 2.27.0