From patchwork Wed Dec 5 07:43:59 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "jianchao.wang" X-Patchwork-Id: 10713101 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 185DA13BF for ; Wed, 5 Dec 2018 07:44:48 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id EBAF52CC2D for ; Wed, 5 Dec 2018 07:44:47 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C5EEC2CC57; Wed, 5 Dec 2018 07:44:47 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6799A2CC2D for ; Wed, 5 Dec 2018 07:44:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726351AbeLEHoq (ORCPT ); Wed, 5 Dec 2018 02:44:46 -0500 Received: from userp2120.oracle.com ([156.151.31.85]:42996 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726102AbeLEHoq (ORCPT ); Wed, 5 Dec 2018 02:44:46 -0500 Received: from pps.filterd (userp2120.oracle.com [127.0.0.1]) by userp2120.oracle.com (8.16.0.22/8.16.0.22) with SMTP id wB57i48q129835; Wed, 5 Dec 2018 07:44:42 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id : in-reply-to : references; s=corp-2018-07-02; bh=B2zNxyNngGK6JzHyyb7FVpzffaYVgPFHJVpgTzXKJBc=; b=JG4JBfwN7u0lw5RuFiI8zYp6y1xK7j59W6eGoq4nSdoQv7N1M1xCBPbduBmSuTtoiroY /MutwyjE+hof4KvkXlHhNmsfjmOWbz76ds7whKltF2dEqb3EP8ls5xlVjmKuatfr1ErN WZ83t0JwbDlJd3LGBlGgsMvtSt9JewreEl1/O74PBt6lUxmCfQ+EyuhEp19cbqI7k5e6 1Tz1Mj8Vy5x6AVYfO4Iri7MMQa08m5jD1d08Cvn//m7IbYpvX45axKYr+6vNyUCMZrW9 gLJeRDJ3QxQF/OXyVzJN7c/QbDeFy+HZsRLMdhF/UsEmlZwFEUM3N5Rm4xMWpjGGLEzQ YQ== Received: from aserv0021.oracle.com (aserv0021.oracle.com [141.146.126.233]) by userp2120.oracle.com with ESMTP id 2p3jxrgpvj-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 05 Dec 2018 07:44:42 +0000 Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by aserv0021.oracle.com (8.14.4/8.14.4) with ESMTP id wB57ifUb002756 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 5 Dec 2018 07:44:41 GMT Received: from abhmp0011.oracle.com (abhmp0011.oracle.com [141.146.116.17]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id wB57ifi4025491; Wed, 5 Dec 2018 07:44:41 GMT Received: from will-ThinkCentre-M93p.cn.oracle.com (/10.182.70.234) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Tue, 04 Dec 2018 23:44:40 -0800 From: Jianchao Wang To: axboe@kernel.dk Cc: ming.lei@redhat.com, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH V9 1/4] blk-mq: insert to hctx dispatch list when bypass_insert is true Date: Wed, 5 Dec 2018 15:43:59 +0800 Message-Id: <1543995842-20704-2-git-send-email-jianchao.w.wang@oracle.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1543995842-20704-1-git-send-email-jianchao.w.wang@oracle.com> References: <1543995842-20704-1-git-send-email-jianchao.w.wang@oracle.com> X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=9097 signatures=668686 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=1 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-1812050072 Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP 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; + } + if (!blk_mq_get_dispatch_budget(hctx)) goto insert; @@ -1849,8 +1860,12 @@ static blk_status_t __blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx, return __blk_mq_issue_directly(hctx, rq, cookie, last); insert: - if (bypass_insert) + if (force) { + blk_mq_request_bypass_insert(rq, run_queue); + return BLK_STS_OK; + } else if (bypass_insert) { return BLK_STS_RESOURCE; + } blk_mq_sched_insert_request(rq, false, run_queue, false); return BLK_STS_OK;