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=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 7E124C43461 for ; Tue, 13 Apr 2021 13:19:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5AB3C613AB for ; Tue, 13 Apr 2021 13:19:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345995AbhDMNTa (ORCPT ); Tue, 13 Apr 2021 09:19:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43678 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345980AbhDMNTY (ORCPT ); Tue, 13 Apr 2021 09:19:24 -0400 Received: from mail-oi1-x22a.google.com (mail-oi1-x22a.google.com [IPv6:2607:f8b0:4864:20::22a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 09F35C061574 for ; Tue, 13 Apr 2021 06:19:05 -0700 (PDT) Received: by mail-oi1-x22a.google.com with SMTP id x2so16955587oiv.2 for ; Tue, 13 Apr 2021 06:19:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=+lMWYPNRgjHfGJ2IGynOc/e2UwksaNHcfV33RwyFvJc=; b=MLovbU708M86ukdmzujhwKR2SfF/Kewm/N7w2ooqHqcICoeeDsN0mvEF8lIdDWF6jx jTASP6qAuAPkXVVP5kRdC4y7IuXIGhORnP44X7D2WktQgRCZCBoNKr7WR8yDojonIHrF mK0RFQSxYe8ZUHGnhSE6FTLFl0y7HXSIHDD4jnrHoinGB5ZKNBdjuA/Jg1ZkxB+m8wDD PG5WP3X6quMzfOaoEc6y/VEmWsbwLxbFXU7oGJD/NBdX2lGCFy+SEoIaDRVG89dYm9iH Od6CnjqrqyLfGO0ANRbBPLT20VmGtfbWXtHi4R3IxPgSYv8PRQ9z7Es58w7PYerLLxod BnzA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=+lMWYPNRgjHfGJ2IGynOc/e2UwksaNHcfV33RwyFvJc=; b=Q5/WFKXIkdIFnFbQhhQO59tX+/YKznJ7o8Zs8r/dSSCeXKF8kln5sds10qr8nedmuO 2KgdKQK9YGhLRQ+5kPd++8Va70Bspxqfbl20a8maQL4AACflMsIjlDgGTd40RmGsgrKY vYjHvFy4AiWn1/zRumiQbaNpghgTKk7wFkwfg65sZHF2nkH+W05OtFZs4yadlwVCiRg7 Uaci1HZ64C3QHTozMFq50pG9dgSNVLColNFVxjbO8UV4WRI+91RO5Xs7uP2NNGN1gabH SuElc1mQwIYpBk3O9ccAssd9mX3BM6xa4MsQGC/okWK6rT85LtwJZ1ZaG9ApIBPIvnBP UWPA== X-Gm-Message-State: AOAM531Esdg4GJsCMaCSRBsHMERvnTjSuTfqUOQLKMC41Cycz31od+Ca jhp4GZGUTRtEwkmT83q7MBA= X-Google-Smtp-Source: ABdhPJzRvTvT7S7M8GS+Uom/UCGNj2bqytIgONGBxPcyXrd5SArrwFHF091BOUOIBK7LKp/I8pg39g== X-Received: by 2002:aca:39d6:: with SMTP id g205mr3282295oia.81.1618319944420; Tue, 13 Apr 2021 06:19:04 -0700 (PDT) Received: from localhost.localdomain ([50.236.19.102]) by smtp.gmail.com with ESMTPSA id v1sm2854207ooh.3.2021.04.13.06.18.59 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Tue, 13 Apr 2021 06:19:03 -0700 (PDT) From: qianjun.kernel@gmail.com To: mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de Cc: linux-kernel@vger.kernel.org, jun qian Subject: [PATCH 1/1] sched/fair:Reduce unnecessary check preempt in the sched tick Date: Tue, 13 Apr 2021 21:18:42 +0800 Message-Id: <20210413131842.44430-1-qianjun.kernel@gmail.com> X-Mailer: git-send-email 2.20.1 (Apple Git-117) MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: jun qian If it has been determined that the current cpu need resched in the early stage of for_each_sched_entity, then there is no need to check preempt in the subsequent se->parent entity_tick. Signed-off-by: jun qian --- kernel/sched/fair.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 1a68a0536add..c0d135100d54 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -4352,8 +4352,13 @@ check_preempt_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr) { unsigned long ideal_runtime, delta_exec; struct sched_entity *se; + struct rq *rq = rq_of(cfs_rq); s64 delta; + /* If the TIF_NEED_RESCHED has been set, it is no need to check again */ + if (test_tsk_need_resched(rq->curr)) + return; + ideal_runtime = sched_slice(cfs_rq, curr); delta_exec = curr->sum_exec_runtime - curr->prev_sum_exec_runtime; if (delta_exec > ideal_runtime) { -- 2.18.2