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=-8.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 D480ECA9ECB for ; Fri, 1 Nov 2019 02:15:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A69EB208CB for ; Fri, 1 Nov 2019 02:15:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="ROpihfoo" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728538AbfKACPD (ORCPT ); Thu, 31 Oct 2019 22:15:03 -0400 Received: from userp2120.oracle.com ([156.151.31.85]:39100 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727492AbfKACPC (ORCPT ); Thu, 31 Oct 2019 22:15:02 -0400 Received: from pps.filterd (userp2120.oracle.com [127.0.0.1]) by userp2120.oracle.com (8.16.0.27/8.16.0.27) with SMTP id xA12DiUV140621; Fri, 1 Nov 2019 02:14:49 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=subject : to : cc : references : from : message-id : date : mime-version : in-reply-to : content-type : content-transfer-encoding; s=corp-2019-08-05; bh=+D5uZVrrm2UUwBzgJZjbEAL/lxOpZVzPX8fBvNBqg+8=; b=ROpihfooAfUBgl605qGxVr1Uam3xdsvmJemdAWh9+EOZ+jP+GrJ3XMloQVwGsNJ97Uck YrajK3+qtmbYBXzxGse7amlxYr+vfsERdAeDz1292F/YxZ5VdkQBHRGgKekBHbC0DzOs 3CYKbcAfZApLhszMYvp2vaA8CjBAnJMpo55F0CWo7OZ9liOSotQBty054zVCgqAWDn5+ /PvWxPD+ttL5aOR+ddcF9GTCYoND3rzQThyk+sdnJqExSmI7irSYzjSpswmaJDuFN8Co OwgvxdZIKgbtdWUlm4dUMLQzEqChyELPAeEKFN+kO+o8L6H60KabGItwvjQyNnSFerKT kQ== Received: from aserp3020.oracle.com (aserp3020.oracle.com [141.146.126.70]) by userp2120.oracle.com with ESMTP id 2vxwhfxvww-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 01 Nov 2019 02:14:49 +0000 Received: from pps.filterd (aserp3020.oracle.com [127.0.0.1]) by aserp3020.oracle.com (8.16.0.27/8.16.0.27) with SMTP id xA12EL2n076724; Fri, 1 Nov 2019 02:14:49 GMT Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by aserp3020.oracle.com with ESMTP id 2vysbvyd2r-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 01 Nov 2019 02:14:48 +0000 Received: from abhmp0007.oracle.com (abhmp0007.oracle.com [141.146.116.13]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id xA12Ekig026521; Fri, 1 Nov 2019 02:14:46 GMT Received: from [192.168.1.14] (/114.88.246.185) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 31 Oct 2019 19:14:46 -0700 Subject: Re: [PATCH] io_uring: set -EINTR directly when a signal wakes up in io_cqring_wait To: Jackie Liu , axboe@kernel.dk Cc: linux-block@vger.kernel.org References: <1572319002-9943-1-git-send-email-liuyun01@kylinos.cn> From: Bob Liu Message-ID: Date: Fri, 1 Nov 2019 10:14:43 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.5.1 MIME-Version: 1.0 In-Reply-To: <1572319002-9943-1-git-send-email-liuyun01@kylinos.cn> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9427 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=18 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1911010020 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9427 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=18 phishscore=0 bulkscore=0 spamscore=0 clxscore=1011 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1911010020 Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On 10/29/19 11:16 AM, Jackie Liu wrote: > We didn't use -ERESTARTSYS to tell the application layer to restart the > system call, but instead return -EINTR. we can set -EINTR directly when > wakeup by the signal, which can help us save an assignment operation and > comparison operation. > > Signed-off-by: Jackie Liu Looks good to me. Reviewed-by: Bob Liu > --- > fs/io_uring.c | 9 +++------ > 1 file changed, 3 insertions(+), 6 deletions(-) > > diff --git a/fs/io_uring.c b/fs/io_uring.c > index a30c4f6..63eee7e 100644 > --- a/fs/io_uring.c > +++ b/fs/io_uring.c > @@ -2878,7 +2878,7 @@ static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events, > .to_wait = min_events, > }; > struct io_rings *rings = ctx->rings; > - int ret; > + int ret = 0; > > if (io_cqring_events(rings) >= min_events) > return 0; > @@ -2896,7 +2896,6 @@ static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events, > return ret; > } > > - ret = 0; > iowq.nr_timeouts = atomic_read(&ctx->cq_timeouts); > do { > prepare_to_wait_exclusive(&ctx->wait, &iowq.wq, > @@ -2905,15 +2904,13 @@ static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events, > break; > schedule(); > if (signal_pending(current)) { > - ret = -ERESTARTSYS; > + ret = -EINTR; > break; > } > } while (1); > finish_wait(&ctx->wait, &iowq.wq); > > - restore_saved_sigmask_unless(ret == -ERESTARTSYS); > - if (ret == -ERESTARTSYS) > - ret = -EINTR; > + restore_saved_sigmask_unless(ret == -EINTR); > > return READ_ONCE(rings->cq.head) == READ_ONCE(rings->cq.tail) ? ret : 0; > } >