From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from m16.mail.163.com (m16.mail.163.com [220.197.31.4]) (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 912EF3BB135; Thu, 10 Sep 2026 06:17:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=220.197.31.4 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789021034; cv=none; b=STxpswzehNT8FBQQ3gc3tjOpaeyEafUngJZUtECikGSuhQ08LF62JE1fUzlMsytK6Mr53YBSLNGD9khu82UdhjwBHRcEx+CcdHBDr4Z6qlpBBkYmR8nZV0oDhua6IOTB7diGwHr5Z4JsgkBjpcvmBrNZsok5k8mu6v0RCmEmHT8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789021034; c=relaxed/simple; bh=W5n1szKTlD2UUANHlXzPnHSKm2VVYA14OjCDAdDsGfo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=BNXtGZKEua2DoiOyh6aX9r0ueg3mt9A+/zBxMQfFnyCh/WCaKhyHe6xd2HBTC59snT8HMSm5ZMfvKGOE5A67zKuptrnDKl4Qb+CWaoNywIG3q08YL4fMzwwaLwYBkvxQGeTWpPbGx0JdUMu4Wvl7qH3g9KHduHbd+UkZscJQu+g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com; spf=pass smtp.mailfrom=163.com; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b=MyEFahQy; arc=none smtp.client-ip=220.197.31.4 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=163.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b="MyEFahQy" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:To:Subject:Date:Message-ID:MIME-Version; bh=W5 n1szKTlD2UUANHlXzPnHSKm2VVYA14OjCDAdDsGfo=; b=MyEFahQymaFAFSk6Zp ZXIFTwPjpqXBMJUriw7hN4naGzL4bh97QwEQaREyyJsRJqg5VJ6QnoznPJkg4ABU Mj/JpwWyNq/IjLWzZixhyV3lUWzxZXpfnmWUhCt7FV6wGsElqPjilCLaw5Q71Tj9 n1AGYQ9wJRmtM/lDAzxEEgtd4= Received: from sky.localdomain (unknown []) by gzga-smtp-mtada-g0-4 (Coremail) with SMTP id _____wD3_5krS6JqpT+PBw--.37361S2; Thu, 10 Sep 2026 14:16:12 +0800 (CST) From: Junnan Zhang To: tj@kernel.org Cc: cgroups@vger.kernel.org, hannes@cmpxchg.org, linux-kernel@vger.kernel.org, mkoutny@suse.com, ridong.chen@linux.dev, sunshx@chinatelecom.cn, zhangjn_dev@163.com Subject: Re: [PATCH v3] cgroup: avoid flushing global workqueue in cgroup1_pidlist_destroy_all Date: Thu, 10 Sep 2026 14:16:10 +0800 Message-ID: <20260910061610.91209-1-zhangjn_dev@163.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: References: Precedence: bulk X-Mailing-List: cgroups@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CM-TRANSID:_____wD3_5krS6JqpT+PBw--.37361S2 X-Coremail-Antispam: 1Uf129KBjDUn29KB7ZKAUJUUUUU529EdanIXcx71UUUUU7v73 VFW2AGmfu7bjvjm3AaLaJ3UbIYCTnIWIevJa73UjIFyTuYvjTRRc_aDUUUU X-CM-SenderInfo: x2kd0wxmqbvvry6rljoofrz/xtbC7QwhtmqiSywFxQAA3Z Hi Tejun, Thanks for the clarification -- agreed that the 120s stall needs to be convincingly attributed before this can count as a minimal fix. I'll put together a reproducer that drives only cgroup churn plus cgroup.procs readers on an otherwise idle machine, with measured cgroup1_pidlist_destroy_all() latencies (and a lowered hung_task_timeout_secs to catch actual splats), and report back with the numbers. It'll take me a few days to set up. Thanks, Junnan