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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 32C46C43334 for ; Sat, 9 Jul 2022 15:16:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229648AbiGIPQH (ORCPT ); Sat, 9 Jul 2022 11:16:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51092 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229564AbiGIPPv (ORCPT ); Sat, 9 Jul 2022 11:15:51 -0400 Received: from mail-pg1-x533.google.com (mail-pg1-x533.google.com [IPv6:2607:f8b0:4864:20::533]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4F4004AD42 for ; Sat, 9 Jul 2022 08:15:49 -0700 (PDT) Received: by mail-pg1-x533.google.com with SMTP id s27so1254962pga.13 for ; Sat, 09 Jul 2022 08:15:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20210112.gappssmtp.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=r3mxdMtzYN4EG2h1+j1zeQY1fxjwsNicM4bDMcwOEsI=; b=7u0xD4mTqOLbBezgkWkuZtIRvBOqah++R4agGmLSbq+QuvxRnkEM15nWPvShqHXPBT NXQR1TJTEcVa3HYCFAWE4K65/6HCS0vDdKqXXZR1QhVwr3Q3cHujwPgg1h9MKVFkgv8Z Ry/Qg2qTfh3M6wP2x3hr3YhASxgQZNwUn4Fxb2ToWQCK/tcylUUhVAmh06CSN6CITDsL Le/O3eyZn3EFB9bsP1xaa3WTFKAf2NVN4+Lt5WsVdfMEZPmfFy2+kQCC5ZwPlAT/gves iFB3QfJXmNmOL/8HJkLK1BwISr6zRdUJXcOtlPEvp8YKsEgSGS9abdjmuJx6/+Otp+h8 fRHg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=r3mxdMtzYN4EG2h1+j1zeQY1fxjwsNicM4bDMcwOEsI=; b=WZd/4iy/5n3SjiZMr1YCjCwHVo+od1ixEHms7BgCi5X5BAAvDMrKDuzJj7KgG3CMd6 6j6X7CHjM6cvEUriBU4DnLbHEAdxHoP2tyi706JQzx3ja4FDrT2Jwrh1PGEyrZNXKCQS sk+NsvA3Aiz88OntvyweWE1+hFy3An3pwgzz1/mSpeZeqIQQ19ODYhTYodlwFrsJIQq5 pr1XKpeuefTDkmiJRiuqgHTekGNbYbQ/hC75UwTBvkm+FLk0sTZhhFCWKU9Oqdc8tcj6 ei+EDZJHRUP3u/a3zf0kTH9c7ORZpUPexgn+3exaPyQyKpaDd3MaaogNbOTgosFFS+hR UkFw== X-Gm-Message-State: AJIora+FVuamCSfKA3zph6KSuPJc48+jMNOToLzgpG2dL4mxwJ+LLdv/ +YGSM/AmPPfii5OTXELZyz7wKA== X-Google-Smtp-Source: AGRyM1u4ITSSIedQ0QLA9OhiYdi+G3XG/9XwxCU/ntryEEx2YnWFoXG+saoGBggSt2zY0XLwLiairA== X-Received: by 2002:aa7:8186:0:b0:528:c344:ed6e with SMTP id g6-20020aa78186000000b00528c344ed6emr9281105pfi.35.1657379748820; Sat, 09 Jul 2022 08:15:48 -0700 (PDT) Received: from localhost.localdomain ([2409:8a28:e63:e730:5493:aabd:e56d:65e6]) by smtp.gmail.com with ESMTPSA id bo20-20020a17090b091400b001ef8d2f72fesm1295709pjb.45.2022.07.09.08.15.42 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 09 Jul 2022 08:15:48 -0700 (PDT) From: Chengming Zhou To: mingo@redhat.com, peterz@infradead.org, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, vschneid@redhat.com Cc: linux-kernel@vger.kernel.org, Chengming Zhou Subject: [PATCH 6/8] sched/fair: stop load tracking when task switched_from_fair() Date: Sat, 9 Jul 2022 23:13:51 +0800 Message-Id: <20220709151353.32883-7-zhouchengming@bytedance.com> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220709151353.32883-1-zhouchengming@bytedance.com> References: <20220709151353.32883-1-zhouchengming@bytedance.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The same reason as the previous commit, if we don't reset the sched_avg last_update_time to 0, after a while in switched_to_fair(): switched_to_fair attach_task_cfs_rq attach_entity_cfs_rq update_load_avg __update_load_avg_se(now, cfs_rq, se) The delta (now - sa->last_update_time) will wrongly contribute/decay sched_avg depends on the task running/runnable status at that time. This patch reset it's sched_avg last_update_time to 0, stop load tracking for !fair task, later in switched_to_fair() -> update_load_avg(), we can use its saved sched_avg. Signed-off-by: Chengming Zhou --- kernel/sched/fair.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 153a2c6c1069..ca714eedeec5 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -11563,6 +11563,11 @@ static void attach_task_cfs_rq(struct task_struct *p) static void switched_from_fair(struct rq *rq, struct task_struct *p) { detach_task_cfs_rq(p); + +#ifdef CONFIG_SMP + /* Stop load tracking for !fair task */ + p->se.avg.last_update_time = 0; +#endif } static void switched_to_fair(struct rq *rq, struct task_struct *p) -- 2.36.1