From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from 013.lax.mailroute.net (013.lax.mailroute.net [199.89.1.16]) (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 103D0286D63; Thu, 4 Dec 2025 19:07:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=199.89.1.16 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764875230; cv=none; b=IHCWsqXfLEb5mkUVFnRSEKhNPnSlS7PdAOtAcg3Z7xsls7BssOnNqP5nTdMN3QDrnoG/qieuH8tEEyvT+y48xmpPHurrMMK6Uh1wQOC36gcBdaYGOa39heTcDgWdbgAvw4n4feLRb98Tvnnz5Up7tJjuBMTv7q6+NT8v492X2+M= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764875230; c=relaxed/simple; bh=9z9kLeY5DYOVlHM9zpdwcoUUCBdXdLFLwQESdtgXMjg=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=IiMosRWLgynvI0JoRYMfSik5VahdvcnEGdMySIK+PFJ2x4tPn+ApcvDDKUpcyhE3kfffa/+E096beqxlcZe7/criZ7gzbxhf+8ciz+axtoneZTRRi0mBQL66o2heST9G2/K/GbtKIplLsKoYVdFYDLLMfhhK9N+H9dbcReCC54Q= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=acm.org; spf=pass smtp.mailfrom=acm.org; dkim=pass (2048-bit key) header.d=acm.org header.i=@acm.org header.b=aA1XOYX6; arc=none smtp.client-ip=199.89.1.16 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=acm.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=acm.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=acm.org header.i=@acm.org header.b="aA1XOYX6" Received: from localhost (localhost [127.0.0.1]) by 013.lax.mailroute.net (Postfix) with ESMTP id 4dMkX86PqhzlxWdb; Thu, 4 Dec 2025 19:07:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=acm.org; h= content-transfer-encoding:content-type:content-type:in-reply-to :from:from:content-language:references:subject:subject :user-agent:mime-version:date:date:message-id:received:received; s=mr01; t=1764875221; x=1767467222; bh=Sxd/Aif4YOWMwisvLZs1jz8U DO3+wD2UJitwu5+0+40=; b=aA1XOYX6RSpT8owyMnR+f1C+LVSP+WXgI1mbf7U1 VrBv+EyKudu3LzWT4/8cbIKwlh5fDVdw9JAWqpGAmJTBVTsgMcLy9OmdUu//t++O qjwyEI44j0fwfKecnwTZRVmDsQevOKrqPHi1pV0RsCZZTQZG7QcR/p8FlnKVbPd8 vq7V9h+fib6qOGIjfhcDa85m4m6HGtw5vQGhg5qshMz68C8SCSqBWQHAoGM4x6cY ax6373nIg3XTHMBkuKRag5EdcTFxv/i2HEs0+hAGdTesyeR+7x6EXBzta8aJfKkH Op1rg+VbxTry6veh8LgpD52p85pKpxLUs+AHfpRsK4YiQw== X-Virus-Scanned: by MailRoute Received: from 013.lax.mailroute.net ([127.0.0.1]) by localhost (013.lax [127.0.0.1]) (mroute_mailscanner, port 10029) with LMTP id JGOgnh3WSgQO; Thu, 4 Dec 2025 19:07:01 +0000 (UTC) Received: from [10.22.10.72] (syn-098-153-230-237.biz.spectrum.com [98.153.230.237]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: bvanassche@acm.org) by 013.lax.mailroute.net (Postfix) with ESMTPSA id 4dMkWt4TLVzlfdfW; Thu, 4 Dec 2025 19:06:49 +0000 (UTC) Message-ID: <71e9950f-ace7-4570-a604-ceca347eea20@acm.org> Date: Thu, 4 Dec 2025 09:06:47 -1000 Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 1/1] block: Use RCU in blk_mq_[un]quiesce_tagset() instead of set->tag_list_lock To: Mohamed Khalfella Cc: Chaitanya Kulkarni , Christoph Hellwig , Jens Axboe , Keith Busch , Sagi Grimberg , Casey Chen , Yuanyuan Zhong , Hannes Reinecke , Ming Lei , Waiman Long , Hillf Danton , linux-nvme@lists.infradead.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org References: <20251204181212.1484066-1-mkhalfella@purestorage.com> <20251204181212.1484066-2-mkhalfella@purestorage.com> <5450d3fa-3f00-40ae-ac95-1f08886de3b6@acm.org> <20251204184243.GZ337106-mkhalfella@purestorage.com> Content-Language: en-US From: Bart Van Assche In-Reply-To: <20251204184243.GZ337106-mkhalfella@purestorage.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 12/4/25 8:42 AM, Mohamed Khalfella wrote: > Is blk_mq_del_queue_tag_set() performance sensitive such that it can not > take synchronize_rcu()? It is not in IO codepath, right? Introducing a new synchronize_rcu() call almost always slows down some workload so it should be avoided if possible. > I can not think of an easy way to do that. Suggestions are welcomed. I can't find the implementation of nvme_dev_disable_locked(). What kernel tree does your patch apply to? $ git grep -w nvme_dev_disable_locked axboe-block/for-next | wc -l 0 Thanks, Bart.