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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id B487DC54E4A for ; Fri, 8 Mar 2024 15:21:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=DUdweC4GDAyOiPhdZj7J9g6BZ4MwdI+RnObnmDW0L9I=; b=mKrGbGWYHxFY1fqyTN2p76HqTt FRa6ZlREQzSwcpwAEr23TtiUc9LPkzIEP+2XQJ/yX1iczHiiWI8JWiTQ42y7IHJ75trFK8zesN/iP mTxMwD96Skmv/CXq9/5v2T6xlBlpBqmyCNuBT6PHdU/ZihairqtWCaOhypVjjUcuYuEhDJyxTJ89P KKQwrNUEXkRGfaWXEoIMBVHqt6+lb62dgMn5M5jSE9GRNgXmWbTQdVPUsRToXTJjMXbladqf1MkM4 k6/Z+nSu+tavxa/Y+10Kc9B1Ia+YoWsH15Nj4WtdBqebiZ7GU2AzQWFeOj0y6R816JaxkD+pcG32c +l37lWGw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1ric2H-00000009p6U-1oY4; Fri, 08 Mar 2024 15:21:25 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1ric2E-00000009p3a-22Ab for linux-nvme@lists.infradead.org; Fri, 08 Mar 2024 15:21:23 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 4CA3C68BEB; Fri, 8 Mar 2024 16:21:13 +0100 (CET) Date: Fri, 8 Mar 2024 16:21:12 +0100 From: Christoph Hellwig To: Keith Busch Cc: Christoph Hellwig , Jens Axboe , Chandan Babu R , linux-block@vger.kernel.org, linux-nvme@lists.infradead.org, linux-xfs@vger.kernel.org Subject: Re: [PATCH 06/10] ext4: switch to using blk_next_discard_bio directly Message-ID: <20240308152112.GA11963@lst.de> References: <20240307151157.466013-1-hch@lst.de> <20240307151157.466013-7-hch@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240308_072122_691900_547DE339 X-CRM114-Status: GOOD ( 17.94 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On Thu, Mar 07, 2024 at 09:13:01AM -0700, Keith Busch wrote: > On Thu, Mar 07, 2024 at 08:11:53AM -0700, Christoph Hellwig wrote: > > @@ -3840,12 +3840,16 @@ static inline int ext4_issue_discard(struct super_block *sb, > > trace_ext4_discard_blocks(sb, > > (unsigned long long) discard_block, count); > > if (biop) { > > Does this 'if' case even need to exist? It looks unreachable since there > are only two callers of ext4_issue_discard(), and they both set 'biop' > to NULL. It looks like the last remaining caller using 'biop' was > removed with 55cdd0af2bc5ffc ("ext4: get discard out of jbd2 commit > kthread contex") Yeah. I didn't really want to dig so far into code I don't know well for this series, though :) > > + while (blk_next_discard_bio(sb->s_bdev, biop, §or, > > + &nr_sects, GFP_NOFS)) > > + ; > > This pattern is repeated often in this series, so perhaps a helper > function for this common use case. Well, it's 2-3 lines vs 1 line for a much better interface.