From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (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 E6DA6C8CE; Fri, 25 Aug 2023 14:20:53 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B30AF2718; Fri, 25 Aug 2023 07:20:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=rIMc/jDCj9ILMqoJd0dO659w/9cB73A1MIGl7MCNQc0=; b=oBoPRF9uQlcnzO+kvA9HXiHIxh 1BCZOYk+GNL3b9Hbl9e0kK321R7GUMuXBq5CnzZVygX8jax4dLYLnGd1XSzW1m9qVXov6cTXOpVyv sv5l1EBw3uu95Jxon5Sw3wlu1qTTRFkBQCTr+N8L/Prb1jdIi5jstgZjfRsnuOwWr9LDfkxjeCY5c UoI4nSwH2jPxj2QMMHZp0Wkb5xy7QvRuP3ObBs4CYLKVGqr6YBri4brVlX/zJEjbKcNGc0kRvuWzw 6Da7DA+BObM8TzfQI+r1SxtKCOrEiJNsg27vpqxgEagx4gi10g2HUFqfKuMQw4f6GgzpXJkYlNle8 RUhWro7w==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1qZXfd-00HYsg-Qa; Fri, 25 Aug 2023 14:20:17 +0000 Date: Fri, 25 Aug 2023 15:20:17 +0100 From: Matthew Wilcox To: Hao Xu Cc: io-uring@vger.kernel.org, Jens Axboe , Dominique Martinet , Pavel Begunkov , Christian Brauner , Alexander Viro , Stefan Roesch , Clay Harris , Dave Chinner , "Darrick J . Wong" , linux-fsdevel@vger.kernel.org, linux-xfs@vger.kernel.org, linux-ext4@vger.kernel.org, linux-cachefs@redhat.com, ecryptfs@vger.kernel.org, linux-nfs@vger.kernel.org, linux-unionfs@vger.kernel.org, bpf@vger.kernel.org, netdev@vger.kernel.org, linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, linux-btrfs@vger.kernel.org, codalist@coda.cs.cmu.edu, linux-f2fs-devel@lists.sourceforge.net, cluster-devel@redhat.com, linux-mm@kvack.org, linux-nilfs@vger.kernel.org, devel@lists.orangefs.org, linux-cifs@vger.kernel.org, samba-technical@lists.samba.org, linux-mtd@lists.infradead.org, Wanpeng Li Subject: Re: [PATCH 12/29] xfs: enforce GFP_NOIO implicitly during nowait time update Message-ID: References: <20230825135431.1317785-1-hao.xu@linux.dev> <20230825135431.1317785-13-hao.xu@linux.dev> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230825135431.1317785-13-hao.xu@linux.dev> X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_BLOCKED, SPF_HELO_NONE,SPF_NONE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net On Fri, Aug 25, 2023 at 09:54:14PM +0800, Hao Xu wrote: > +++ b/fs/xfs/xfs_iops.c > @@ -1037,6 +1037,8 @@ xfs_vn_update_time( > int log_flags = XFS_ILOG_TIMESTAMP; > struct xfs_trans *tp; > int error; > + int old_pflags; > + bool nowait = flags & S_NOWAIT; > > trace_xfs_update_time(ip); > > @@ -1049,13 +1051,18 @@ xfs_vn_update_time( > log_flags |= XFS_ILOG_CORE; > } > > + if (nowait) > + old_pflags = memalloc_noio_save(); > + > error = xfs_trans_alloc(mp, &M_RES(mp)->tr_fsyncts, 0, 0, 0, &tp); This is an abuse of the memalloc_noio_save() interface. You shouldn't be setting it around individual allocations; it's the part of the kernel which decides "I can't afford to do I/O" that should be setting it. In this case, it should probably be set by io_uring, way way way up at the top. But Jens didn't actually answer my question about that: https://lore.kernel.org/all/ZMhZh2EYPMH1wIXX@casper.infradead.org/