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=-8.8 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_PASS autolearn=unavailable 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 91C38C07E85 for ; Thu, 6 Dec 2018 01:11:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 57088214C1 for ; Thu, 6 Dec 2018 01:11:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="SHdrCm3L" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 57088214C1 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=oracle.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728880AbeLFBLc (ORCPT ); Wed, 5 Dec 2018 20:11:32 -0500 Received: from aserp2130.oracle.com ([141.146.126.79]:46994 "EHLO aserp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727575AbeLFBLb (ORCPT ); Wed, 5 Dec 2018 20:11:31 -0500 Received: from pps.filterd (aserp2130.oracle.com [127.0.0.1]) by aserp2130.oracle.com (8.16.0.22/8.16.0.22) with SMTP id wB619idc001560; Thu, 6 Dec 2018 01:11:27 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-2018-07-02; bh=BpHNERcP+usiB6ijW7Vv6qJrTws/14F5ApTXtGpapeo=; b=SHdrCm3LZgYtqOOjHSBm/0pPxuV6jwPuifnTPMd9n1rN+qJRt3b9EqL8d72tgcbVrXmF 3z9YvRQcIYlqEACOmHH8edFXPqmf2cpamCiQu6gIgWE4r1glSpbn/8SORz0g9cE++v4j LvTzAXJyJ7sBC1ICp/jfaxfRICejKjBIXT3aQr6Qz1aQi7iQArOA7MjO/W0+QogtMjVH jjKbGi/PV6rK3AofgdZi6tuS3nyWaLo01b0K6B6kVBYU5Co+2AHQhOEt6/mGV00PyDxh fhPYYoS9sFzwhw6DjQfrLcbt8o1wpJNUdQpn1yQ6JjHJv1vKK4Gzbpyv3GDETg9/3Njn hg== Received: from userv0022.oracle.com (userv0022.oracle.com [156.151.31.74]) by aserp2130.oracle.com with ESMTP id 2p3ftf9keb-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 06 Dec 2018 01:11:27 +0000 Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by userv0022.oracle.com (8.14.4/8.14.4) with ESMTP id wB61BLB9006459 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 6 Dec 2018 01:11:21 GMT Received: from abhmp0020.oracle.com (abhmp0020.oracle.com [141.146.116.26]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id wB61BL70011296; Thu, 6 Dec 2018 01:11:21 GMT Received: from [10.182.71.8] (/10.182.71.8) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 06 Dec 2018 01:11:21 +0000 Subject: Re: [PATCH V9 1/4] blk-mq: insert to hctx dispatch list when bypass_insert is true To: Jens Axboe Cc: ming.lei@redhat.com, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org References: <1543995842-20704-1-git-send-email-jianchao.w.wang@oracle.com> <1543995842-20704-2-git-send-email-jianchao.w.wang@oracle.com> <54c7377f-e8e6-92cf-eced-6c76297afd52@kernel.dk> From: "jianchao.wang" Message-ID: <99339021-4d05-8dff-bee4-a6af2eaf3e21@oracle.com> Date: Thu, 6 Dec 2018 09:12:02 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.2.1 MIME-Version: 1.0 In-Reply-To: <54c7377f-e8e6-92cf-eced-6c76297afd52@kernel.dk> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=9098 signatures=668679 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1812060007 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/6/18 12:25 AM, Jens Axboe wrote: > On 12/5/18 12:43 AM, Jianchao Wang wrote: >> We don't allow direct dispatch of anything but regular reads/writes >> and insert all of non-read-write requests. However, this is not >> correct for 'bypass_insert == true' case where inserting is ignored >> and BLK_STS_RESOURCE is returned. The caller will fail forever. >> >> Fix it with inserting the non-read-write request to hctx dispatch >> list to avoid to involve merge and io scheduler when bypass_insert >> is true. >> >> Signed-off-by: Jianchao Wang >> --- >> block/blk-mq.c | 19 +++++++++++++++++-- >> 1 file changed, 17 insertions(+), 2 deletions(-) >> >> diff --git a/block/blk-mq.c b/block/blk-mq.c >> index 9005505..153af90 100644 >> --- a/block/blk-mq.c >> +++ b/block/blk-mq.c >> @@ -1822,6 +1822,7 @@ static blk_status_t __blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx, >> { >> struct request_queue *q = rq->q; >> bool run_queue = true; >> + bool force = false; >> >> /* >> * RCU or SRCU read lock is needed before checking quiesced flag. >> @@ -1836,9 +1837,19 @@ static blk_status_t __blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx, >> goto insert; >> } >> >> - if (!blk_rq_can_direct_dispatch(rq) || (q->elevator && !bypass_insert)) >> + if (q->elevator && !bypass_insert) >> goto insert; >> >> + if (!blk_rq_can_direct_dispatch(rq)) { >> + /* >> + * For 'bypass_insert == true' case, insert request into hctx >> + * dispatch list. >> + */ >> + if (bypass_insert) >> + force = true; >> + goto insert; >> + } > > Just do force = bypass_insert, no need for the if. > Yes, I will do it. Thanks Jianchao