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=-16.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,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 9938AC433DB for ; Wed, 3 Mar 2021 11:44:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4959364ED7 for ; Wed, 3 Mar 2021 11:44:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233196AbhCCLjY (ORCPT ); Wed, 3 Mar 2021 06:39:24 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42270 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1352585AbhCCD4n (ORCPT ); Tue, 2 Mar 2021 22:56:43 -0500 Received: from mail-pf1-x430.google.com (mail-pf1-x430.google.com [IPv6:2607:f8b0:4864:20::430]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6B4F3C061224 for ; Tue, 2 Mar 2021 19:47:20 -0800 (PST) Received: by mail-pf1-x430.google.com with SMTP id j12so15266494pfj.12 for ; Tue, 02 Mar 2021 19:47:20 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=mikBinDMbyRpVEpCpcCv+zMSrFXfTIIjvNTlhZImavg=; b=Qbyu2CCXt/1FVCjpDjFCpFvzcKzHY5Z7YgcF/qgD3DrEeMeawUr5TPGj1IMyjJRksE 4eoAjTfV9HKa68N0RTZZ3shWU7hFo4XZncMAnGQpAw3Q6uK6PIfKtgjAGi+68i8u9b13 F1ne2HTfX7PU4qcRLtRWXjVKQ/Jmu0N2vgcG66xjrS01JkfFrtaUwQ6pkhdDkVEt8H09 ejXqmSgL1ZU7tcwpcfpJwdHObvUbxHc4rcbHCevr7/BXszsrHk//5fblMYPFS3nbi0MO +YunGA0VtvzbQVtqKS0MZWHaH9jjvtlyhB0URhmelj0LU/8bBiCPBbjuvUhSJ1H3FCff FL1Q== 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:in-reply-to :references:mime-version:content-transfer-encoding; bh=mikBinDMbyRpVEpCpcCv+zMSrFXfTIIjvNTlhZImavg=; b=tSffYxbx8ff0Ehl/pSZM+9/I+7gOdH7GLGW6Ul+na0Fpe+q2PrD64zbqhpOwcyU1Ef fHPdvA77Afe+ufQI3iL+UayLjWsD8Ts23vjw5PnUmzugxSmw3DifrnsLcecKn0YNQvH7 I+hFW5JMWbFYVsF0dvX13vCktQQK5J4F2AADRT7oNiLTIgDwq352OSxQUhL2wnOqidvc 7Wj5liAG3FqDef25FDXEXaz0SXHkukIaHJHh+/q5jnPgkcrYpRgY76KpNlCRx7/GWX2I v0ggQ3LJCde2PB18MHB0enhvg9fWiaxShikqefalPLAmv+91wAxu2C16fr7gHRM8tMTW 3A3Q== X-Gm-Message-State: AOAM5316SR6+Yl08jovC4kXoZyJL1EA4QZhdR529dvW0k/vtra5nHI3A N2UozDg76pDZ9JJ5sigQQdr0Lw== X-Google-Smtp-Source: ABdhPJyMO5Hy0y3mxK60JsHtrzWWdevaVgfI3jIIyNzo8rAmyg4HT/aGQpOLa9w2vxoHu4g6sK7DnA== X-Received: by 2002:aa7:92c7:0:b029:1ee:75b2:2dab with SMTP id k7-20020aa792c70000b02901ee75b22dabmr1376199pfa.61.1614743240055; Tue, 02 Mar 2021 19:47:20 -0800 (PST) Received: from C02CV1DAMD6P.bytedance.net ([139.177.225.246]) by smtp.gmail.com with ESMTPSA id p26sm23029703pfn.127.2021.03.02.19.47.16 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Tue, 02 Mar 2021 19:47:19 -0800 (PST) From: Chengming Zhou To: hannes@cmpxchg.org, mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org Cc: linux-kernel@vger.kernel.org, songmuchun@bytedance.com, zhouchengming@bytedance.com Subject: [PATCH v2 3/4] psi: pressure states are unlikely Date: Wed, 3 Mar 2021 11:46:58 +0800 Message-Id: <20210303034659.91735-4-zhouchengming@bytedance.com> X-Mailer: git-send-email 2.24.3 (Apple Git-128) In-Reply-To: <20210303034659.91735-1-zhouchengming@bytedance.com> References: <20210303034659.91735-1-zhouchengming@bytedance.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Johannes Weiner Move the unlikely branches out of line. This eliminates undesirable jumps during wakeup and sleeps for workloads that aren't under any sort of resource pressure. Signed-off-by: Johannes Weiner --- kernel/sched/psi.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/kernel/sched/psi.c b/kernel/sched/psi.c index 0fe6ff6a6a15..3907a6b847aa 100644 --- a/kernel/sched/psi.c +++ b/kernel/sched/psi.c @@ -219,17 +219,17 @@ static bool test_state(unsigned int *tasks, enum psi_states state) { switch (state) { case PSI_IO_SOME: - return tasks[NR_IOWAIT]; + return unlikely(tasks[NR_IOWAIT]); case PSI_IO_FULL: - return tasks[NR_IOWAIT] && !tasks[NR_RUNNING]; + return unlikely(tasks[NR_IOWAIT] && !tasks[NR_RUNNING]); case PSI_MEM_SOME: - return tasks[NR_MEMSTALL]; + return unlikely(tasks[NR_MEMSTALL]); case PSI_MEM_FULL: - return tasks[NR_MEMSTALL] && !tasks[NR_RUNNING]; + return unlikely(tasks[NR_MEMSTALL] && !tasks[NR_RUNNING]); case PSI_CPU_SOME: - return tasks[NR_RUNNING] > tasks[NR_ONCPU]; + return unlikely(tasks[NR_RUNNING] > tasks[NR_ONCPU]); case PSI_CPU_FULL: - return tasks[NR_RUNNING] && !tasks[NR_ONCPU]; + return unlikely(tasks[NR_RUNNING] && !tasks[NR_ONCPU]); case PSI_NONIDLE: return tasks[NR_IOWAIT] || tasks[NR_MEMSTALL] || tasks[NR_RUNNING]; @@ -729,7 +729,7 @@ static void psi_group_change(struct psi_group *group, int cpu, * task in a cgroup is in_memstall, the corresponding groupc * on that cpu is in PSI_MEM_FULL state. */ - if (groupc->tasks[NR_ONCPU] && cpu_curr(cpu)->in_memstall) + if (unlikely(groupc->tasks[NR_ONCPU] && cpu_curr(cpu)->in_memstall)) state_mask |= (1 << PSI_MEM_FULL); groupc->state_mask = state_mask; -- 2.11.0