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 92F36CFD2FD for ; Fri, 11 Oct 2024 09:18:19 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 208686B0082; Fri, 11 Oct 2024 05:18:19 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 1B80D6B0088; Fri, 11 Oct 2024 05:18:19 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 031566B00AE; Fri, 11 Oct 2024 05:18:18 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id D856F6B00AB for ; Fri, 11 Oct 2024 05:18:18 -0400 (EDT) Received: from smtpin28.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 903FA40FB6 for ; Fri, 11 Oct 2024 09:18:15 +0000 (UTC) X-FDA: 82660770234.28.E4BD532 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) by imf15.hostedemail.com (Postfix) with ESMTP id 82891A0009 for ; Fri, 11 Oct 2024 09:18:13 +0000 (UTC) Authentication-Results: imf15.hostedemail.com; dkim=pass header.d=infradead.org header.s=bombadil.20210309 header.b=Quf8GJzg; spf=none (imf15.hostedemail.com: domain of BATV+0c28974be301e84ba5dc+7719+infradead.org+hch@bombadil.srs.infradead.org has no SPF policy when checking 198.137.202.133) smtp.mailfrom=BATV+0c28974be301e84ba5dc+7719+infradead.org+hch@bombadil.srs.infradead.org; dmarc=none ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1728638225; a=rsa-sha256; cv=none; b=kLCLXjT1dteY7yHzYoYly7czh/H252KXt54LdhJUs3bp/QO+J1dl12SV3ACA32qpGQRttm h6IB42yHHRSb0LBC0xzbXaHMxmll9Mr8NKX/94JKcm0jDIHliDB4R53glvFHBh3f7iKTvs Ac0hKw5tkT5HhNCciGcQSh1Gnz+34+A= ARC-Authentication-Results: i=1; imf15.hostedemail.com; dkim=pass header.d=infradead.org header.s=bombadil.20210309 header.b=Quf8GJzg; spf=none (imf15.hostedemail.com: domain of BATV+0c28974be301e84ba5dc+7719+infradead.org+hch@bombadil.srs.infradead.org has no SPF policy when checking 198.137.202.133) smtp.mailfrom=BATV+0c28974be301e84ba5dc+7719+infradead.org+hch@bombadil.srs.infradead.org; dmarc=none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1728638225; 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=lU4r4tbL0K3+5Mx7gnspEYb/vcINY3gT5cXeOgb5F4w=; b=7H0dd+hHCFpkdkmfEWI26/BAHa4pBr/QbUeI71Lj/VwU5Hc2PJK/EOEylBpCKctgbjyXwJ r34h9xGF3k/byZ/rrhTVtuK6sW+0wsH/ektQ+g7+gjdrG0hur24ZwhW8SpjVqPdKVRmCje mXqTzOznorns8DoztkX+KjznzkV4tCw= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; 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=lU4r4tbL0K3+5Mx7gnspEYb/vcINY3gT5cXeOgb5F4w=; b=Quf8GJzgeSqTUbUf2AO61bq2LU Vf+sqE1ISUAtcou7pFQzSVWv9InCaQKBoNd0afkNiv10L1mfVdLAfuZqdRMl/eVzwvg1LIjnPSgRK bKGLaoP6oKtAZ0+iIW2SuFuA9IX5rlhBRy2PApzCAuKxL5P39veXhGyuBZikJB5HCpCMvAy/RPwhk x+iQBynF6YG1b170b2ADWCDkmbV+l3SIixwMM+ABeReVdPFfffqfyxC8IpG4uEF7f5C0GB0e8yg9O ROhve62AuLOSgCtv0FBgCduv+2YocVTwKa+gGZ5aSE9GPjg+5J5xpstuLLxyrAoBK+jWMzLm2wGew PN1kCL1w==; Received: from hch by bombadil.infradead.org with local (Exim 4.98 #2 (Red Hat Linux)) id 1szBmb-0000000FnpU-3CEE; Fri, 11 Oct 2024 09:18:01 +0000 Date: Fri, 11 Oct 2024 02:18:01 -0700 From: Christoph Hellwig To: Qun-Wei Lin Cc: Jens Axboe , Minchan Kim , Sergey Senozhatsky , Vishal Verma , Dan Williams , Dave Jiang , Ira Weiny , Andrew Morton , Matthias Brugger , AngeloGioacchino Del Regno , "Huang, Ying" , Chris Li , Ryan Roberts , David Hildenbrand , Kairui Song , "Matthew Wilcox (Oracle)" , Dan Schatzberg , Barry Song , linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, nvdimm@lists.linux.dev, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, Casper Li , Chinwen Chang , Andrew Yang , John Hsu , wsd_upstream@mediatek.com Subject: Re: [PATCH] mm: Split BLK_FEAT_SYNCHRONOUS and SWP_SYNCHRONOUS_IO into separate read and write flags Message-ID: References: <20241011091133.28173-1-qun-wei.lin@mediatek.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20241011091133.28173-1-qun-wei.lin@mediatek.com> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html X-Stat-Signature: dh94z1t99dmfieqg44reoye76hdoawyx X-Rspamd-Queue-Id: 82891A0009 X-Rspam-User: X-Rspamd-Server: rspam10 X-HE-Tag: 1728638293-337612 X-HE-Meta: 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 Z3j67Swu 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 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: List-Subscribe: List-Unsubscribe: On Fri, Oct 11, 2024 at 05:11:33PM +0800, Qun-Wei Lin wrote: > This patch splits the BLK_FEAT_SYNCHRONOUS feature flag into two > separate flags: BLK_FEAT_READ_SYNCHRONOUS and > BLK_FEAT_WRITE_SYNCHRONOUS. Similarly, the SWP_SYNCHRONOUS_IO flag is > split into SWP_READ_SYNCHRONOUS_IO and SWP_WRITE_SYNCHRONOUS_IO. > > These changes are motivated by the need to better accommodate certain > swap devices that support synchronous read operations but asynchronous write > operations. > > The existing BLK_FEAT_SYNCHRONOUS and SWP_SYNCHRONOUS_IO flags are not > sufficient for these devices, as they enforce synchronous behavior for > both read and write operations. You're still failing to provide a user. Without that it is dead in the water from the very beginning.