From nobody Fri Dec 19 03:42:43 2025 Received: from mail-oi1-f170.google.com (mail-oi1-f170.google.com [209.85.167.170]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5EE4518D4DC for ; Tue, 30 Jul 2024 07:59:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.170 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722326360; cv=none; b=Z4WHNIJLl3RGEM4AVvNCciO3vQLBwOSYyapCuxCCXBMtWBLdhHcklzBI0uWjxYt1IdSJ5RAv5cJp1CLQXv0yZKhIIWAxSmolLIkCt9C6LI8rYQCk6e1h3Qm4Ihjs4nhkfdFDylmuFljAMi0lDAMLiGQZjH2Y1FfYGZG/R31MTeY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722326360; c=relaxed/simple; bh=GEPj04JmoCgXOe4WCmAyy3NgAbiGw36D79b9P5r4TRs=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=Xq9MI6cU0vSkLj/w4VILY6nKjAMrEju77OOixlxRhwyqZavuUTGobODfahOwGrWmF/ZLd0q25Ck8JZ1LW28bRdUH9O14JmehKytVWOUw4CKHuAhVSnfajYk8CTLg9ayFiyiDqi9RYIthD68SczTz1CltR4YZWmy8kX5/E/Im9Vg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=Dw64Tnq6; arc=none smtp.client-ip=209.85.167.170 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Dw64Tnq6" Received: by mail-oi1-f170.google.com with SMTP id 5614622812f47-3db18102406so3075418b6e.1 for ; Tue, 30 Jul 2024 00:59:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1722326357; x=1722931157; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=hsKrDsbFmiXtekqhMmrRnCYwYxG76SWUBxZQ5Lytsdw=; b=Dw64Tnq6Eh4UbgZhn+u/9j8NUNzrW4jspAHfrqp1fXwCHua5CmCC6BgWMYfNNLn7G8 Kq8m3TD3tejun8u+exB99P6wEWx/BaYdq0KRfyIMsxyZ4QjIZkDmaUF5KQno7kvCFjjY C4SnJ1MAiLdS1Vk8WZratQi/HR6B4n92BdqLvR+/QoCL7gh+FV9SkSnVOAavue1gFuIT 8UFhxIgK2aGwuwUPnGQC0rwynLrlFNJPx20zzi17IIMrQxwiUo8KpYgoPuuqMrRhHVI6 GLOI6yDkugWK0OzpONSmdw9o1adkAMn3CQpxF6m6DStyzJHWh3BbCbMSX1V8IpsYfAd4 1czg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1722326357; x=1722931157; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=hsKrDsbFmiXtekqhMmrRnCYwYxG76SWUBxZQ5Lytsdw=; b=L7iCmMh6rjOWd4/74IRAF6dMSu1lCcM+gnmwJj9+A590u7URE8P1rKk82NDwyZU+fu OXB9HLUfQA2W5bpztsauj5a9U8yVSsw4SbQtjHviTExkRsAtsTo28zRq0uc2cHvsi53g 7UIVcVq+uOvlcGPj+X6fT+X3467/cE5g9Ljc+WmVoB0JdU+D86YxTVG0EJ5wqN+tjvAL vKlkqYoAeCmL3OcXSbxaEG1MeQBwkZExOuPPDd+WkTre4cWjlxKieQe7ta/h4uAkkR3J 21NcHnKb8j7CkxkuIvr55M5NJB1cHIe3YnmoAlWh4ytHWcMTm0Ww6qIt7vfb7I0wjQHi Cl5w== X-Gm-Message-State: AOJu0Yw4q+gPs5iE25tVZrWrmSr3oUXRsA+e61xIjGD2lkFvRGngGLKM GbJfvjVgARYVc+tVtd5De+nRtLVoM3XK/yPAdPdotcATa37VVNKv X-Google-Smtp-Source: AGHT+IFxKFvFu3SsmFJtaeNIMKdg7DSpe5vNzLXHSgNZ50E+DMZCLOz0cLjsK9a2hwFT4s6Y+fYFFQ== X-Received: by 2002:a05:6870:d8c6:b0:254:a917:cb38 with SMTP id 586e51a60fabf-267d4d4fa1cmr10713833fac.27.1722326357245; Tue, 30 Jul 2024 00:59:17 -0700 (PDT) Received: from localhost.localdomain ([36.111.64.84]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-70ead715540sm7898813b3a.45.2024.07.30.00.59.14 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 30 Jul 2024 00:59:16 -0700 (PDT) From: wujing To: mingo@redhat.com, peterz@infradead.org Cc: linux-kernel@vger.kernel.org, dongml2@chinatelecom.cn, wujing , wujing , QiLiang Yuan Subject: [PATCH] sched/fair: Correct CPU selection from isolated domain Date: Tue, 30 Jul 2024 15:59:10 +0800 Message-ID: <20240730075910.573-1-realwujing@gmail.com> X-Mailer: git-send-email 2.45.2 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" We encountered an issue where the kernel thread `ksmd` runs on the PMD dedicated isolated core, leading to high latency in OVS packets. Upon analysis, we discovered that this is caused by the current select_idle_smt() function not taking the sched_domain mask into account. Kernel version: linux-4.19.y Signed-off-by: wujing Signed-off-by: QiLiang Yuan --- kernel/sched/fair.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 09f82c84474b..0950cabfc1d0 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -6171,7 +6171,8 @@ static int select_idle_smt(struct task_struct *p, str= uct sched_domain *sd, int t return -1; =20 for_each_cpu(cpu, cpu_smt_mask(target)) { - if (!cpumask_test_cpu(cpu, &p->cpus_allowed)) + if (!cpumask_test_cpu(cpu, &p->cpus_allowed) || + !cpumask_test_cpu(cpu, sched_domain_span(sd))) continue; if (available_idle_cpu(cpu)) return cpu; --=20 2.45.2