From nobody Sun Feb 8 11:49:50 2026 Received: from out203-205-221-245.mail.qq.com (out203-205-221-245.mail.qq.com [203.205.221.245]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3FF9C150981 for ; Tue, 30 Jul 2024 07:11:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=203.205.221.245 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722323482; cv=none; b=WrdFSLm0Rh0RiizivrmGyOQkJK6sO+/ljGcUBAMqflXP1Zshzzd4s5xKJ2RkTDrF9MSxVIPUHHkxwS6r37a+ONX7yfumOFlg7pjEKVFvZrhcuSunRch77DCZuZ8JTrlhgP5UX5S31wlQP8yjsmizguwJSnqBf9/1hzmy1Babbvs= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722323482; c=relaxed/simple; bh=GEPj04JmoCgXOe4WCmAyy3NgAbiGw36D79b9P5r4TRs=; h=Message-ID:From:To:Cc:Subject:Date:MIME-Version; b=mF85GU7OH52MoZmxr0vP3dijMQUzqTQTAFldRT2UPrqHUj74qBljRQR/vHtwuTlYfkE+ZwPaM6Y5/1iYtZF9SN2u8cx1wtoFH4CPDOi5aq2OSukohVIPbSEOiqlyC9LPEpwQRmLm5AMF3jLZZP7cv2wSREyLMoHSHNLAzmfDQSc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=qq.com; spf=pass smtp.mailfrom=qq.com; dkim=pass (1024-bit key) header.d=qq.com header.i=@qq.com header.b=fnk/43Go; arc=none smtp.client-ip=203.205.221.245 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=qq.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=qq.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=qq.com header.i=@qq.com header.b="fnk/43Go" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=qq.com; s=s201512; t=1722323476; bh=hsKrDsbFmiXtekqhMmrRnCYwYxG76SWUBxZQ5Lytsdw=; h=From:To:Cc:Subject:Date; b=fnk/43GonYvpvTb8rHb2R/U6oStODxa4DaVbfqUHUsSEDOY2Wu0r8eP9qwMwvu3B2 4Y0F0f6ujKuyDXHg1PPHO0Xbj9QUx69cgAe1TH6uHhfyOlyy9/7BoCVxVXUVfe9Nl/ xYVunzwE3U/h2UQww9G3zY6rBsK0iulrKXaumTRk= Received: from localhost.localdomain ([36.111.64.84]) by newxmesmtplogicsvrszb16-1.qq.com (NewEsmtp) with SMTP id 2CD88887; Tue, 30 Jul 2024 15:11:13 +0800 X-QQ-mid: xmsmtpt1722323473t9w32s7wc Message-ID: X-QQ-XMAILINFO: NAtipnnbTPea/lPgy65sokbF3GvXJm4tAMsp4fpZ/fjMmk0+iSyOefNnLNX+Or 8aFm017/+YZ8//41ds5NwMYcvX3EPMABaIF/wU8qrq607WNke7B2BGvFzLJLe3+bRv9n02QVWqEj e7eTcJEB+V4RyqQYLWQ/W0cofRQmo3hRWi1GlzC9+x5mrLAP0RgkLhOv2h7t+R1YWUm3rXoqdjOy LNa7u2ZBVlaAZYCvG9OL5KaOEPU+sxER/iQLVR6f57Zt4NPbYdeXkEMhPukNt5lG7aAdO46mOjH/ 6SxcVtOosmy4/MOWyYRc/wo7If5DrgHaxNU0WHg7nSa8bvTXod7PdaEO3WjT4lF2WG+Smvp0gUBW ttxENTjZKDJH67QAeS4PlDQkV4fPCbeJcaHcDVFOLU1hQBsWgRRAMIye9CoJh17yVmpEyHV9gmXv AAFHNyMX0IuQuboPnGDTiQeoKoFfP93cJAvbNYlpJB/QEWExPhV+Yrsf9bMvTlS37Dray8a+aGGk U0Sa6nIK+I+1i7MLti7H1Kmj++x1wRU6blEhGec6ARZPFHj4fheYK6Qvx4pl+DR5QyxeyuwKg/DR iAoFDt3zClvxCkanhcv/q0JmptM0UtsWobUmgfoRdG3Pg+8rZx2NbyX1yPZg1sEOK4cPDXcnW3f4 qzxcvqAwJLj8M3etLO98VuiOat9wBBRE1am8esMVgyADv1S4Jwp29+QMaS2kSLE8gABwCHPTiLzQ VPr+/BO2AF6r9I+sXBmzRQfRlBlJFVTR5kn7c3F5/BSnuOOS6lvSxq3HnkUON717ZJ/303Q40VeD FdBrRcrAv+u2wZY5MuUC3JEOSp47/YBhOTKkGP5J07562Jky2sExwMzek2amB+vEvuCKeFz6utj4 o6ARJyyYL2yFl+ddL0Z9UshckWdEuWYz7igO9mVwRyt8LpaOO8wENdiOoAnQxXQouyzwmYQ77Ix+ xjOqu1oK3Wg0YSbtL62RVZp/MUULoWzJFGq4AJrlreAL7iEb7NEg== X-QQ-XMRINFO: NS+P29fieYNw95Bth2bWPxk= From: wujing To: mingo@redhat.com, peterz@infradead.org Cc: linux-kernel@vger.kernel.org, dongml2@chinatelecom.cn, wujing , QiLiang Yuan Subject: [PATCH] sched/fair: Correct CPU selection from isolated domain Date: Tue, 30 Jul 2024 15:10:50 +0800 X-OQ-MSGID: <20240730071050.78478-1-realwujing@qq.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