From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mta1.migadu.com (out-205.mta1.migadu.com [95.215.58.205]) (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 D8C913BC668 for ; Tue, 22 Sep 2026 03:22:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.205 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790047346; cv=none; b=sIKUugz8RW5aKkARsul80tgFDKB13z3WvSB5R/50zUpfi3ZL/cAsIjDDoSbRnFIlnB+kV57faBsuI8UzutBa0mk/mFZmcmlTfoeMfW99VyS4ZC2b7Y/qUFtUG3bBiO9UMzIUHkW8M/jb14JxU2udlLcGR951N0qmfncO+LKN8zw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790047346; c=relaxed/simple; bh=pauak53psAXKLYl2w6xPdGBF4uRbBTPOApr/KH0j4F0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=DVb7YljdYOM1I9bFolyrYAESPUhUWhtvCyiRGQvWgx04KVJAj+p2MvGI92ObcxLUh9e0hSnjD8+dpDmonfcP6amsmogO3RlaOP0XNXVmiai/3JE3KBlxiJ5Los2nMnNlAQLY25bYLxU9h+jycw1JTxHSYHTZmpfyj8K/htSRLSc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=C49OkL7L; arc=none smtp.client-ip=95.215.58.205 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="C49OkL7L" X-Envelope-To: linux-kernel@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=pauak53psAXKLYl2w6xPdGBF4uRbBTPOApr/KH0j4F0=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1790047342; v=1; x=1790652142; b=C49OkL7LFYddJEhZEUbvcbZ7weqRfBRST96EE5phGSn+Y4HpyVtwmBauz/6M93+u3U8P1zGx jogztmXF0UczPe6VC6xW4KiqW/+z+3kkd03OdZEe+bjJDFhrZBLTdDWAL0fwciqPoVkPsx0LWKh wvtSPaHaBstwm2iFC1DbVQ2s= X-Envelope-To: linux-kernel@vger.kernel.org Received: by smtp.migadu.com with ESMTPS id ebad361c0570f0a0; Tue, 22 Sep 2026 03:22:22 +0000 X-Mizu-Trace-ID: ebad361c0570f0a0 X-Migadu-Flow: FLOW_OUT From: Guopeng Zhang To: Waiman Long , Ridong Chen Cc: Tejun Heo , Johannes Weiner , =?UTF-8?q?Michal=20Koutn=C3=BD?= , Jonathan Corbet , Shuah Khan , cgroups@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, Guopeng Zhang Subject: [PATCH v2 1/2] docs: cgroup-v2: Describe boot-isolated CPUs in cpuset.cpus.isolated Date: Tue, 22 Sep 2026 11:21:29 +0800 Message-ID: <20260922032130.33777-2-guopeng.zhang@linux.dev> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260922032130.33777-1-guopeng.zhang@linux.dev> References: <20260922032130.33777-1-guopeng.zhang@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Guopeng Zhang cpuset.cpus.isolated is documented as empty when no isolated partition exists. This is not true when CPUs are isolated at boot with isolcpus=domain. cpuset_init() adds those CPUs to the isolated mask, and isolcpus= uses domain isolation by default. They remain listed after a partition using them is released. Document the boot-isolated CPUs as well. Suggested-by: Ridong Chen Reviewed-by: Ridong Chen Signed-off-by: Guopeng Zhang --- Documentation/admin-guide/cgroup-v2.rst | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst index 2ec582985b5b..18a01ce4c334 100644 --- a/Documentation/admin-guide/cgroup-v2.rst +++ b/Documentation/admin-guide/cgroup-v2.rst @@ -2626,8 +2626,9 @@ Cpuset Interface Files A read-only and root cgroup only multiple values file. This file shows the set of all isolated CPUs used in existing - isolated partitions. It will be empty if no isolated partition - is created. + isolated partitions or isolated at boot time via the "domain" + flag of "isolcpus". The latter remain listed even after any + partition using them is released. cpuset.cpus.partition A read-write single value file which exists on non-root -- 2.43.0