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=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, UNPARSEABLE_RELAY,USER_AGENT_GIT 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 7625EC433DF for ; Mon, 25 May 2020 10:48:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 57F1820787 for ; Mon, 25 May 2020 10:48:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389522AbgEYKss (ORCPT ); Mon, 25 May 2020 06:48:48 -0400 Received: from out30-132.freemail.mail.aliyun.com ([115.124.30.132]:49355 "EHLO out30-132.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389484AbgEYKss (ORCPT ); Mon, 25 May 2020 06:48:48 -0400 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R411e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e01355;MF=jiufei.xue@linux.alibaba.com;NM=1;PH=DS;RN=3;SR=0;TI=SMTPD_---0TzaHfUT_1590403724; Received: from localhost(mailfrom:jiufei.xue@linux.alibaba.com fp:SMTPD_---0TzaHfUT_1590403724) by smtp.aliyun-inc.com(127.0.0.1); Mon, 25 May 2020 18:48:44 +0800 From: Jiufei Xue To: io-uring@vger.kernel.org Cc: axboe@kernel.dk, joseph.qi@linux.alibaba.com Subject: [PATCH] io_uring: don't set REQ_F_NOWAIT if the file was opened O_NONBLOCK Date: Mon, 25 May 2020 18:48:44 +0800 Message-Id: <1590403724-57101-1-git-send-email-jiufei.xue@linux.alibaba.com> X-Mailer: git-send-email 1.8.3.1 Sender: io-uring-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org When read from an ondisk file that was opened O_NONBLOCK, it will always return EAGAIN to the user if the page is not cached. It is not compatible with interfaces such as aio_read() and normal sys_read(). Files that care about this flag (eg. pipe, eventfd) will deal with it on their own. So I don't think we should set REQ_F_NOWAIT in io_prep_rw() to provent from queueing the async work. Signed-off-by: Jiufei Xue --- fs/io_uring.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index bb25e39..65ae59b 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -2080,8 +2080,7 @@ static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe, kiocb->ki_ioprio = get_current_ioprio(); /* don't allow async punt if RWF_NOWAIT was requested */ - if ((kiocb->ki_flags & IOCB_NOWAIT) || - (req->file->f_flags & O_NONBLOCK)) + if (kiocb->ki_flags & IOCB_NOWAIT) req->flags |= REQ_F_NOWAIT; if (force_nonblock) -- 1.8.3.1