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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id A5B30C83F16 for ; Tue, 29 Aug 2023 11:53:53 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 0DDC18E0027; Tue, 29 Aug 2023 07:53:53 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 08E648E001A; Tue, 29 Aug 2023 07:53:53 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E976C8E0027; Tue, 29 Aug 2023 07:53:52 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id DA7088E001A for ; Tue, 29 Aug 2023 07:53:52 -0400 (EDT) Received: from smtpin13.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id A5BF2C0723 for ; Tue, 29 Aug 2023 11:53:52 +0000 (UTC) X-FDA: 81176983104.13.CA3E348 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf19.hostedemail.com (Postfix) with ESMTP id 2C5191A001B for ; Tue, 29 Aug 2023 11:53:48 +0000 (UTC) Authentication-Results: imf19.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=kNMS0YeY; dmarc=none; spf=none (imf19.hostedemail.com: domain of willy@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=willy@infradead.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1693310030; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=YZxpYOTF14BVcouqFhbahruwZXBLTSy2TCKsEoryGgA=; b=BsxYz0JA4s1l6B0hQe2R1L0awT4nyr2rEcsB0OUg5JFvoQOKxPZz8VEg/GMcR+3TGSY1Xt PRiFJPgUp1mDMT/lKQQkbbKwJj1Q7KJIN0D8HIk+43vohYnWOrGnREs4bcKRfHB1SqTuYZ bLC1+Vwchy/z5jYikZ2Vxzm4yeFreRM= ARC-Authentication-Results: i=1; imf19.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=kNMS0YeY; dmarc=none; spf=none (imf19.hostedemail.com: domain of willy@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=willy@infradead.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1693310030; a=rsa-sha256; cv=none; b=ti6WNIdhLpw36M+glu3w4M3q/k1gUeAALExz9/DCk+8bMEtRgaNFw5/amd1i5/+7uXxNzX 2Sq4b9biz9YLI9E5LlEpzf6sBzHp7Rz5J6GB00Fl0Nhvor+WQz0lT4QY69UWD9xRusJ1ZM QAyxe/5zRwnTT5h+B4lxomy6OP0LOrY= 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=YZxpYOTF14BVcouqFhbahruwZXBLTSy2TCKsEoryGgA=; b=kNMS0YeYJE43XRXxkVUmLf2G+X 0F+Ci8x/vmTvip6eYnQqjlZo85hPiq+1XBtqpwy24WfkqxJcN3oDroYdU0hmUGTZO8DmOvrKcLnsA I7wiz/QgNWUfJcZJ1P+jwtCGJuvaBfIm6i+nYBm4G4q1TzqZrEd8vmeeXhUF+nfDcEVXWTUFH8hQX gmgzKK6rDBAyLZFUyKz32+/IHnRsGl+xYuxNBS8JVzpCmXVMJxm/LAsn2AL2YmcWHqJedjjw347sz rnlxqkUfOTw1wHOoS2VuCxy8fDxR1A9rikvDXoQ9fhtzraRL7eHJTnjVX6n6aHUnUp8GZkipnoXzv 988YMF3g==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1qaxHQ-006P4x-1X; Tue, 29 Aug 2023 11:53:08 +0000 Date: Tue, 29 Aug 2023 12:53:07 +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 07/11] vfs: add nowait parameter for file_accessed() Message-ID: References: <20230827132835.1373581-1-hao.xu@linux.dev> <20230827132835.1373581-8-hao.xu@linux.dev> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Queue-Id: 2C5191A001B X-Rspam-User: X-Rspamd-Server: rspam02 X-Stat-Signature: ppkx9cwmgopi5hs7tk1hc71ci89mskfu X-HE-Tag: 1693310028-302139 X-HE-Meta: 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 iJKCAQC2 3y2BuU+ALIpKlk6n6R9f0jaPE7QVdSODty4quSmYzWVYNj6yBjEOZ60BFhjYR5ZmdFqshsec5NJ/OVo5J7i9yBvK/2HWvwBQegDCZaFRo98bC2/6Ge7smZk2aHhlVWCBbkTjirLNk8g30iQMTD63UHFRIHn74CD3bMCxiARm2nGeUE05z44FSeApEaweeK9D7tJvHYW4fBqxNOBO/m3D4xGF8ijin6x4bXPwR0/S5e874TWVrOlCjcywBvlrtsyYY4BKJD9lAwdgZqyjxW0xRKgqN78r7GYYucXgf8lQdRY5DidMTWnBRSJqrrqVSI3/QARXB X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, Aug 29, 2023 at 03:46:13PM +0800, Hao Xu wrote: > On 8/28/23 05:32, Matthew Wilcox wrote: > > On Sun, Aug 27, 2023 at 09:28:31PM +0800, Hao Xu wrote: > > > From: Hao Xu > > > > > > Add a boolean parameter for file_accessed() to support nowait semantics. > > > Currently it is true only with io_uring as its initial caller. > > > > So why do we need to do this as part of this series? Apparently it > > hasn't caused any problems for filemap_read(). > > > > We need this parameter to indicate if nowait semantics should be enforced in > touch_atime(), There are locks and maybe IOs in it. That's not my point. We currently call file_accessed() and touch_atime() for nowait reads and nowait writes. You haven't done anything to fix those. I suspect you can trim this patchset down significantly by avoiding fixing the file_accessed() problem. And then come back with a later patchset that fixes it for all nowait i/o. Or do a separate prep series first that fixes it for the existing nowait users, and then a second series to do all the directory stuff. I'd do the first thing. Just ignore the problem. Directory atime updates cause I/O so rarely that you can afford to ignore it. Almost everyone uses relatime or nodiratime.