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 X-Spam-Level: X-Spam-Status: No, score=-8.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E110FC433E0 for ; Wed, 24 Feb 2021 16:58:13 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 4FFC364F04 for ; Wed, 24 Feb 2021 16:58:13 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4FFC364F04 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id BACE46B0006; Wed, 24 Feb 2021 11:58:12 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id B5CA56B006C; Wed, 24 Feb 2021 11:58:12 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A73176B0070; Wed, 24 Feb 2021 11:58:12 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0121.hostedemail.com [216.40.44.121]) by kanga.kvack.org (Postfix) with ESMTP id 8DE9E6B0006 for ; Wed, 24 Feb 2021 11:58:12 -0500 (EST) Received: from smtpin25.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 4DE4D1801D2EE for ; Wed, 24 Feb 2021 16:58:12 +0000 (UTC) X-FDA: 77853769224.25.ED5DCC6 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf29.hostedemail.com (Postfix) with ESMTP id 779C5E4 for ; Wed, 24 Feb 2021 16:58:11 +0000 (UTC) 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=PfWCmza47JW+IbRVssMx5/wjrLqy2TFMYziwljasB28=; b=YXbmDRERPh7zav8Sh+zSYo4nSV 89ODAQ3f3F1VgFBrZs0EQzknFKdwZYGFkn/vsp0kCxSeJG4lJxKNrbLk6trDujiVZIBAbVuh1b/Ek 52BMp54ALNHrU/FMAaBy1gS0zbe0OBBZMZomKKIn/doB3HulY/0KbRQeQAlBtfC7FFdqtDrdPfe6a ZPLztUdiB7PReoMw9H1S6A15W5HccrhvXmEx8/TLXwNhHrP/XiAv1mk6mctSCjUaqmCglSwCG89Fk E/PdQJBouGPd4/cL5zpB2SXyo+6JaWjqt6tC0dgh6hCzgTgpipldmGBTvi4EgpdfwT7tKWDLdWEk9 kgnlHd6w==; Received: from willy by casper.infradead.org with local (Exim 4.94 #2 (Red Hat Linux)) id 1lExTw-009eED-Q2; Wed, 24 Feb 2021 16:57:52 +0000 Date: Wed, 24 Feb 2021 16:57:48 +0000 From: Matthew Wilcox To: Jens Axboe Cc: linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, akpm@linux-foundation.org Subject: Re: [PATCH 2/3] mm: use filemap_range_needs_writeback() for O_DIRECT reads Message-ID: <20210224165748.GS2858050@casper.infradead.org> References: <20210224164455.1096727-1-axboe@kernel.dk> <20210224164455.1096727-3-axboe@kernel.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210224164455.1096727-3-axboe@kernel.dk> X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 779C5E4 X-Stat-Signature: r919gjw3hf6g6rdw3rcda3xe6ud6pyot Received-SPF: none (infradead.org>: No applicable sender policy available) receiver=imf29; identity=mailfrom; envelope-from=""; helo=casper.infradead.org; client-ip=90.155.50.34 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1614185891-753452 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 Wed, Feb 24, 2021 at 09:44:54AM -0700, Jens Axboe wrote: > For the generic page cache read helper, use the better variant of checking > for the need to call filemap_write_and_wait_range() when doing O_DIRECT > reads. This avoids falling back to the slow path for IOCB_NOWAIT, if there > are no pages to wait for (or write out). > > Signed-off-by: Jens Axboe Reviewed-by: Matthew Wilcox (Oracle)