From nobody Sat Apr 11 19:53:11 2026 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 EC4AAC00140 for ; Mon, 8 Aug 2022 12:59:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243249AbiHHM7Q (ORCPT ); Mon, 8 Aug 2022 08:59:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42724 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243155AbiHHM6u (ORCPT ); Mon, 8 Aug 2022 08:58:50 -0400 Received: from mail-pf1-x42a.google.com (mail-pf1-x42a.google.com [IPv6:2607:f8b0:4864:20::42a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A26D2FD0A for ; Mon, 8 Aug 2022 05:58:37 -0700 (PDT) Received: by mail-pf1-x42a.google.com with SMTP id z187so7994497pfb.12 for ; Mon, 08 Aug 2022 05:58:37 -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=0S4/uQg7L4l7ka3/Aeqj7n7hkrnKAJNq6+H/S+7bfUs=; b=TtKbF2yVWmPUjJZAKRkNmDD2Rx3GAjkV5oDtXp/5pqozM7Yt4zKH1NdY8OUn+ytGAG Zf5n2QIsAlBGD762sAXWh+BwQ26kuv41OF6+//UrSZNKBjpkhQfQPJmTIRkaLyowiNMv laT+ky+EunvlCBfcrkMd5J05galqhlY9S7FL5IMFj8gL8VkrMTC3xfgBVxwyIrdIFQfy oR7xBXokgV2/CHcm3mUJCgtfLSSN6vtg7CA7K0WMyqMj/ugv8/G3lnZzNiZLBXbdPLFB SItmorAtTPJHTp6vEBs95yK+TDAwctBYomAMDNXXHPvkGRixIQpa557BSf71vZueAalQ NmHg== 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=0S4/uQg7L4l7ka3/Aeqj7n7hkrnKAJNq6+H/S+7bfUs=; b=o4I65brbenL2MJIDb0Fs3mJenA4pfiCIYobWlDeJHYt7jQLZ3NllCagXWgJKJA/tZS zn4adMK15S/sMWkKMVrbkdfLvwr5jVO8fQ6l87UrHfiEi2raIxbTQAlTxoUBF8s8wknE FpFnN1BXzbQ4Z/gA5mzVcygFZvGK7Hca6d1aYf1NC0/PTuA5Nu5nYO5kouHMqwXFmOEE p/o3hPDGC5nMf7ifUFujACS3X/iB7aFNqTp1erkwi6Y3T1iFLzkP9qtmN+gOI8lr0V8i rbPuStwVRr2Z1ZbqWmrkM+YqHL11Wt1yZOs+/WZ5v0wswBLYqIamtz9/jbVdtsARXx3u GAGQ== X-Gm-Message-State: ACgBeo3o0H4W3egqet8/6lPOMSMpPbTpmjSNy2K3qtkOFL+urV94vWL9 +gImgC2d/K5f20R497X3YoAQug== X-Google-Smtp-Source: AA6agR5XJ94BdTwgi+yCsDLTSQQxveikvUrql5X8ZTtWNAoRismFWu9BP/Ixul6SqvEMtWOsjoI21g== X-Received: by 2002:a65:5683:0:b0:41c:b103:6037 with SMTP id v3-20020a655683000000b0041cb1036037mr15169870pgs.367.1659963517359; Mon, 08 Aug 2022 05:58:37 -0700 (PDT) Received: from C02CV1DAMD6P.bytedance.net ([139.177.225.240]) by smtp.gmail.com with ESMTPSA id d14-20020a17090ae28e00b001f4ebd47ae7sm8057722pjz.54.2022.08.08.05.58.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 08 Aug 2022 05:58:36 -0700 (PDT) From: Chengming Zhou 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, vschneid@redhat.com Cc: linux-kernel@vger.kernel.org, Chengming Zhou Subject: [PATCH v4 8/9] sched/fair: defer task sched_avg attach to enqueue_entity() Date: Mon, 8 Aug 2022 20:57:44 +0800 Message-Id: <20220808125745.22566-9-zhouchengming@bytedance.com> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220808125745.22566-1-zhouchengming@bytedance.com> References: <20220808125745.22566-1-zhouchengming@bytedance.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" When wake_up_new_task(), we would use post_init_entity_util_avg() to init util_avg/runnable_avg based on cpu's util_avg at that time, then attach task sched_avg to cfs_rq. Since enqueue_entity() would always attach any unattached task entity, so we can defer this work to enqueue_entity(). post_init_entity_util_avg(p) attach_entity_cfs_rq() --> (1) activate_task(rq, p) enqueue_task() :=3D enqueue_task_fair() enqueue_entity() update_load_avg(cfs_rq, se, UPDATE_TG | DO_ATTACH) if (!se->avg.last_update_time && (flags & DO_ATTACH)) attach_entity_load_avg() --> (2) This patch defer attach from (1) to (2) Signed-off-by: Chengming Zhou --- kernel/sched/fair.c | 4 ---- 1 file changed, 4 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 90aba33a3780..2063e30b2a8f 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -799,8 +799,6 @@ void init_entity_runnable_average(struct sched_entity *= se) /* when this task enqueue'ed, it will contribute to its cfs_rq's load_avg= */ } =20 -static void attach_entity_cfs_rq(struct sched_entity *se); - /* * With new tasks being created, their initial util_avgs are extrapolated * based on the cfs_rq's current util_avg: @@ -863,8 +861,6 @@ void post_init_entity_util_avg(struct task_struct *p) se->avg.last_update_time =3D cfs_rq_clock_pelt(cfs_rq); return; } - - attach_entity_cfs_rq(se); } =20 #else /* !CONFIG_SMP */ --=20 2.36.1