From nobody Mon Apr 6 09:43:16 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 B5F5CECAAD5 for ; Thu, 8 Sep 2022 08:07:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231224AbiIHIH0 (ORCPT ); Thu, 8 Sep 2022 04:07:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53854 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231255AbiIHIHV (ORCPT ); Thu, 8 Sep 2022 04:07:21 -0400 Received: from mail-pj1-x1030.google.com (mail-pj1-x1030.google.com [IPv6:2607:f8b0:4864:20::1030]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B3E98D5724 for ; Thu, 8 Sep 2022 01:07:19 -0700 (PDT) Received: by mail-pj1-x1030.google.com with SMTP id z9-20020a17090a468900b001ffff693b27so1584942pjf.2 for ; Thu, 08 Sep 2022 01:07:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20210112.gappssmtp.com; s=20210112; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date; bh=YzUytPikcty1WYKrU+7GKiUQs4mtIiNZsb2UDVO2dPA=; b=cWcRXPvbteaUu350jbBJ1g/PJSCGwmK82zACgnDHTH5LgubfzIPeGbysldTJLebFKZ GGq2u+8LRM9actV9+0IkIdAqtvm9R8s+AQc3fyMX1h2b5iyEMFYHdlvenBmtXyPUc8gn O1f1sjGXGbvpDMy761SXvQ0fwBdY0/lvAWSIV2nOYX1yYbzqPaH3jizZDE5vWlNabKSv QX9RHyGJoFHyS5KsfjzSj+7ffrgB0BslhJcHiRSCAK8oVtSOFbRWSNilEPKVB3Tu7zCI hND64WxV5ut8VPa2KGYwD1z6gDfMaUK3ypOXJJGJGUAQQaSg5NzyeyGcoUQl8i1mUDlf e60g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date; bh=YzUytPikcty1WYKrU+7GKiUQs4mtIiNZsb2UDVO2dPA=; b=wEqbBpw+CDUUNLSsZcN39ZgFaNbU+unMBtjCg4fPvtf4Yin1wuMadXK5pCdIzndJ5w R5tUDdW/oHVXL0n5pKefvbv6ONthl2Od7W95n+dZF8gk1lf2ivDgO7DkNW+tT15z0kHT jFmMRFv6j7ZDBNsqZmMwkI8KS6SmrTeJ4v8N58XfLz/Yhi6219kI575dOuhV1pOkbX9U gM/CfHnqbUQsQ9LqZw4ENw07JZrf0zCrKijmpY1jKcPmT8Czpvk7KpVlUAYeyN2TEV12 l/diy8RccfuGd6H2/h3V0+YZRzIDbNLQZiaLqqElfv80jhSrHImAz4knHINH2GWuXec+ SC5Q== X-Gm-Message-State: ACgBeo12SpcrPCyCjDkqvSUHvuJ4xeayvQAOyAcuDEOexwHdtqAqPfDS v/VIt2/+vOYJ/tLDomG18NBHoA== X-Google-Smtp-Source: AA6agR6oCoelnac7U+zYnru+A9arygx//pWUK1YKaWD/Aum5XbxpdRdj3vrRoHUzTEViWitAe/W2Jg== X-Received: by 2002:a17:90a:74c5:b0:200:2d89:ef13 with SMTP id p5-20020a17090a74c500b002002d89ef13mr2898386pjl.81.1662624439235; Thu, 08 Sep 2022 01:07:19 -0700 (PDT) Received: from C02DV8HUMD6R.bytedance.net ([139.177.225.235]) by smtp.gmail.com with ESMTPSA id c23-20020aa79537000000b0053bbaab3511sm2146067pfp.172.2022.09.08.01.07.16 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Thu, 08 Sep 2022 01:07:19 -0700 (PDT) From: Abel Wu To: Peter Zijlstra , Mel Gorman , Vincent Guittot Cc: Rohit Jain , Ingo Molnar , linux-kernel@vger.kernel.org, Abel Wu Subject: [PATCH] sched/fair: Fix misuse of available_idle_cpu() Date: Thu, 8 Sep 2022 16:07:02 +0800 Message-Id: <20220908080702.58938-1-wuyun.abel@bytedance.com> X-Mailer: git-send-email 2.37.3 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" The function available_idle_cpu() was introduced to distinguish between the code paths that cares if the vCPU is preempted and the ones don't care. In general, available_idle_cpu() is used in selecting cpus for immediate use, e.g. ttwu. While idle_cpu() is used in the paths that only cares about the cpu is idle or not, and __update_idle_core() is one of them. Use idle_cpu() instead in the idle path to make has_idle_core a better hint. Fixes: 943d355d7fee (sched/core: Distinguish between idle_cpu() calls based= on desired effect, introduce available_idle_cpu()) Signed-off-by: Abel Wu Acked-by: Mel Gorman --- kernel/sched/fair.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index efceb670e755..5a76d814f8bc 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -6302,7 +6302,7 @@ void __update_idle_core(struct rq *rq) if (cpu =3D=3D core) continue; =20 - if (!available_idle_cpu(cpu)) + if (!idle_cpu(cpu)) goto unlock; } =20 --=20 2.37.3