From patchwork Fri Apr 30 05:55:21 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 12232365 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=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,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 0C361C43461 for ; Fri, 30 Apr 2021 05:55:24 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id B360E61462 for ; Fri, 30 Apr 2021 05:55:23 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B360E61462 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 589816B00AE; Fri, 30 Apr 2021 01:55:23 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 513D06B00AF; Fri, 30 Apr 2021 01:55:23 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 38D656B00B0; Fri, 30 Apr 2021 01:55:23 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0003.hostedemail.com [216.40.44.3]) by kanga.kvack.org (Postfix) with ESMTP id 17BFF6B00AE for ; Fri, 30 Apr 2021 01:55:23 -0400 (EDT) Received: from smtpin20.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id D912A181AF5C3 for ; Fri, 30 Apr 2021 05:55:22 +0000 (UTC) X-FDA: 78087970884.20.83D1909 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf04.hostedemail.com (Postfix) with ESMTP id 70FEB3C6 for ; Fri, 30 Apr 2021 05:55:18 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id 89D7461466; Fri, 30 Apr 2021 05:55:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1619762121; bh=ZJzsqEPxdBwxeD2jUY1X6y10A3iwrzdYXJcRtkgJY9M=; h=Date:From:To:Subject:In-Reply-To:From; b=R8/xsWCvE3L5tcV4CcPm4Ysic6FiDaNpPvQlLM7VfAIg1IRqGuLDohlafU7i8r4Hv +lWwTFSf0pwmlEKzff4Im78MLz8roCVyDEH1/b9XhPAHxD4BCY+c/w5O5GWXqkvA2Y eQqKSk8vV5pftGT9WYqEwyw434bbbEmLD7XZuj2A= Date: Thu, 29 Apr 2021 22:55:21 -0700 From: Andrew Morton To: akpm@linux-foundation.org, axboe@kernel.dk, jack@suse.cz, linux-mm@kvack.org, mm-commits@vger.kernel.org, torvalds@linux-foundation.org, willy@infradead.org Subject: [patch 042/178] mm: use filemap_range_needs_writeback() for O_DIRECT reads Message-ID: <20210430055521.9-3zLBs9H%akpm@linux-foundation.org> In-Reply-To: <20210429225251.02b6386d21b69255b4f6c163@linux-foundation.org> User-Agent: s-nail v14.8.16 Authentication-Results: imf04.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b="R8/xsWCv"; dmarc=none; spf=pass (imf04.hostedemail.com: domain of akpm@linux-foundation.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org X-Stat-Signature: wphspcw3q83uuszn4toiut6coxs34pib X-Rspamd-Queue-Id: 70FEB3C6 X-Rspamd-Server: rspam05 Received-SPF: none (linux-foundation.org>: No applicable sender policy available) receiver=imf04; identity=mailfrom; envelope-from=""; helo=mail.kernel.org; client-ip=198.145.29.99 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1619762118-257361 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: From: Jens Axboe Subject: mm: use filemap_range_needs_writeback() for O_DIRECT reads 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). Link: https://lkml.kernel.org/r/20210224164455.1096727-3-axboe@kernel.dk Signed-off-by: Jens Axboe Reviewed-by: Matthew Wilcox (Oracle) Reviewed-by: Jan Kara Signed-off-by: Andrew Morton --- mm/filemap.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/mm/filemap.c~mm-use-filemap_range_needs_writeback-for-o_direct-reads +++ a/mm/filemap.c @@ -2681,8 +2681,8 @@ generic_file_read_iter(struct kiocb *ioc size = i_size_read(inode); if (iocb->ki_flags & IOCB_NOWAIT) { - if (filemap_range_has_page(mapping, iocb->ki_pos, - iocb->ki_pos + count - 1)) + if (filemap_range_needs_writeback(mapping, iocb->ki_pos, + iocb->ki_pos + count - 1)) return -EAGAIN; } else { retval = filemap_write_and_wait_range(mapping,