From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=95.215.58.173 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794237671; b=27Ab5QEwfv5koLf24ZXwfTQPZqvjE4WA5/tIFD8OvdAgJTWbqsIgjIOk7VM2qbYYdwc0 PTfgSaF+S2rvoW+HZ6rHR9j2HvQi3B8YnZYiAyDCveDqmOYCMZPjoLmWQAWLVWkSWcJfV Vzav+oGJcdQgrwiFktxqUX9AtOGw+a8WS2BYGsezTs4CUjgw84/JGwVOcHNuVjdwjXSM0 szXBSxcbDVDetKvfGvXJHpChGp6EUMFuhLfdWXxjhybmJy3P/bj4ZSLutlUhVcFj+mHco sMrRV5ZhfIq4Sl167H5d3tTVPPubdXmzbGSXV0E74IY509YMcX46plrdxlGIukEN6tw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794237671; h=DMARC-Filter:X-Envelope-To:DKIM-Signature:X-Envelope-To:Received: X-Mizu-Trace-ID:X-Migadu-Flow:Message-ID:Date:MIME-Version:User-Agent: Subject:To:Cc:References:Content-Language:From:In-Reply-To: Content-Type:Content-Transfer-Encoding; bh=OEaMkvm58VQCFxWgZiNZttKo9RWAkrg2Jpi3EFl1TRY=; b=xZZt+qYhlsNzo3gtneFldEqbUTn7iXXI2wQaqfoVKTOm7AdP8R/0q/WasdThwjtnBYl2 lYb2iQQ8i7KzDcK5QtKVqp9LflUR0Lj+P0ltWHMf4cMVXkfl+hpVyALfrtswyOUnCb4ju P7PbhVNqU8wVmAunx2nhV8xt3lpYnQOjtpk0Fu2naUW1yqvvYi3iwnjbZsAivtIYQXGPg BRO8wYR38QwIncaBS5/9Neh/MRiLIxKbrV8dTI4SGqFhauSyJAWcipvbKMNx9pYg6YYp5 4PwuRjQ4n33+gCEbDJ3qCUgcYIa2SjoN1wmt1Kt5gwX0o3GkCPly37xsp2JkXT0k3Ng== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; arc=none smtp.remote-ip=95.215.58.173 Received: from mta1.migadu.com (out-173.mta1.migadu.com [95.215.58.173]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 15653606A321 for ; Mon, 9 Nov 2026 15:21:03 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 15653606A321 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 X-Envelope-To: linux-kernel@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=kKN1FrR88/XC1lM8GArCouvp/sFgokTYp7hs6x2CE6E=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1794237661; v=1; x=1794842461; b=hzKzNuukR/bLfPSEESlfqIPRohJP6/oZvgw4/qj4TEKohZ4CqfAypR4+ThZoVCV2HrveS0kV IVm+EbUqTbnyTGkmYSjsTpbiwcR9ysoXMp8gOk0ovaRCKzbmqLLDSIGJtcNzZK3BL8YXhGLcw6u ruyRT6LdZJqOU4b+4KnrUMRc= X-Envelope-To: linux-kernel@vger.kernel.org Received: by smtp.migadu.com with ESMTPS id 14f7012e0815e2fe; Mon, 09 Nov 2026 15:21:01 +0000 X-Mizu-Trace-ID: 14f7012e0815e2fe X-Migadu-Flow: FLOW_OUT Message-ID: Date: Mon, 9 Nov 2026 23:20:53 +0800 X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3 3/4] cpuset: settle isolation state when CPUs are given back to parent To: Ridong Chen , Waiman Long , Tejun Heo , Johannes Weiner , =?UTF-8?Q?Michal_Koutn=C3=BD?= , Shuah Khan Cc: Chen Ridong , cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, Sashiko , Guopeng Zhang , Ridong Chen References: <20261107120100.3587595-1-ridong.chen@linux.dev> <20261107120100.3587595-4-ridong.chen@linux.dev> Content-Language: en-US From: Guopeng Zhang In-Reply-To: <20261107120100.3587595-4-ridong.chen@linux.dev> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 在 2026/11/7 20:00, Ridong Chen 写道: > From: Ridong Chen > > partition_xcpus_del() only updates isolated_cpus when the partition that > gives back the CPUs has a different state than its parent. CPUs that were > further distributed to descendant isolated partitions are not taken into > account, so isolated_cpus_release() has to be called afterwards in > several places to walk up the ancestors and fix isolated_cpus. > > Make partition_xcpus_del() always set the isolation state of the given > back CPUs to the state of the parent that receives them. As the > effective_xcpus of a partition covers the CPUs distributed to its > descendants, the isolation state of those CPUs is settled at the same > time. Boot-time isolated CPUs are still preserved by isolated_cpu_update(). > > compute_partition_effective_cpumask() invalidates a child partition > without going through partition_xcpus_del(), so do the same there: the > CPUs of the invalidated child take the isolation state of its parent. > > As the parent may be shrunk and its effective_xcpus not updated yet, > only do so for the CPUs the parent still owns. This is to keep the > isolation state correct for now, the in-place invalidation here will be > removed later in the partition rework. > > isolated_cpus_update() assumes the old and new states are different, > which no longer holds now that partition_xcpus_del() proceeds regardless > of the states. Drop its @old_prs argument and the WARN_ON_ONCE() so that > it simply sets the isolation state of the given CPUs, and use it > everywhere. The state check in partition_xcpus_add() is dropped as well, > as setting the state is a no-op when the states are the same. > > isolated_cpus_release() is no longer needed and is removed. > Hi Ridong, Would it be worth briefly mentioning in the commit message that this patch also fixes the issue described here? https://lore.kernel.org/all/20261105130344.664336-4-guopeng.zhang@linux.dev/ Thanks, Guopeng