From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C15BDC433FE for ; Tue, 1 Nov 2022 17:27:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230249AbiKAR13 (ORCPT ); Tue, 1 Nov 2022 13:27:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56940 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230298AbiKAR10 (ORCPT ); Tue, 1 Nov 2022 13:27:26 -0400 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C74371BEA0; Tue, 1 Nov 2022 10:27:23 -0700 (PDT) Received: by verein.lst.de (Postfix, from userid 2407) id 616CC6732D; Tue, 1 Nov 2022 18:27:20 +0100 (CET) Date: Tue, 1 Nov 2022 18:27:20 +0100 From: Christoph Hellwig To: Jinlong Chen Cc: axboe@kernel.dk, hch@lst.de, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/4] blk-mq: update comment for blk_mq_quiesce_queue_nowait() Message-ID: <20221101172720.GA20526@lst.de> References: <489a9322eed1f95f8770752cc715084f1fa961d3.1667314759.git.nickyc975@zju.edu.cn> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <489a9322eed1f95f8770752cc715084f1fa961d3.1667314759.git.nickyc975@zju.edu.cn> User-Agent: Mutt/1.5.17 (2007-11-01) Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Tue, Nov 01, 2022 at 11:11:34PM +0800, Jinlong Chen wrote: > blk_mq_quiesce_queue_nowait() is now reasonably used by scsi_host_block() > to avoid calling synchronize_rcu() for each LUN. We should not consider to > remove it. I strongly disagree about this being a reasonable use. What SCSI did there is a horrible hack that should have never been merged. The right thing to do is the per-tag_set quiesce that we've been working on.