From patchwork Mon Oct 29 08:33:31 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "jianchao.wang" X-Patchwork-Id: 10658837 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 4EA20174F for ; Mon, 29 Oct 2018 08:34:33 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3BE1128B00 for ; Mon, 29 Oct 2018 08:34:33 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 2D5A0295FA; Mon, 29 Oct 2018 08:34:33 +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 BFD23295FA for ; Mon, 29 Oct 2018 08:34:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726036AbeJ2RVw (ORCPT ); Mon, 29 Oct 2018 13:21:52 -0400 Received: from aserp2120.oracle.com ([141.146.126.78]:37816 "EHLO aserp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729436AbeJ2RVu (ORCPT ); Mon, 29 Oct 2018 13:21:50 -0400 Received: from pps.filterd (aserp2120.oracle.com [127.0.0.1]) by aserp2120.oracle.com (8.16.0.22/8.16.0.22) with SMTP id w9T8TTwq013617; Mon, 29 Oct 2018 08:34:09 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=ljr1AVEDeyqNV2z//1XrWvkspXgCo1lAbTrhPYSDkVY=; b=4iZysp28Gnx43sHBnyCb1jPyW2Q+9mlOOb+NLiAnv5O93edK8fZS4uxX6lICXNRZ/3Az ju0C1wmIyzndC4jgIDtj/zM/IJ9qjPiwt5gM3JBN6d8w3zQwFE1cFUXu82ELSs+O46nR L82pRQbh8iYAF1nMK7VEz2qQpqa0i9e5mqkjZoGzX+RpZh/sTgaR7R3NfF7Oe74R3xwj 56XyPvR/ZrZ1alXCPB7pgULf6As+yjj2lvZj3QGNQ2DX513/TlY7SKuCzRsE2M0cwpaY DgGNuTeFqBSIhxnUgyt4O4lDWoBGxNuxi3Ay/bS3bebAuuW5V4UJrRP2Ov2Rt/IJn3gg nw== Received: from userv0021.oracle.com (userv0021.oracle.com [156.151.31.71]) by aserp2120.oracle.com with ESMTP id 2ncfypm5vd-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 29 Oct 2018 08:34:09 +0000 Received: from userv0122.oracle.com (userv0122.oracle.com [156.151.31.75]) by userv0021.oracle.com (8.14.4/8.14.4) with ESMTP id w9T8Y8jt013068 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 29 Oct 2018 08:34:08 GMT Received: from abhmp0007.oracle.com (abhmp0007.oracle.com [141.146.116.13]) by userv0122.oracle.com (8.14.4/8.14.4) with ESMTP id w9T8Y8ud010591; Mon, 29 Oct 2018 08:34:08 GMT Received: from will-ThinkCentre-M93p.cn.oracle.com (/10.182.70.234) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Mon, 29 Oct 2018 01:34:08 -0700 From: Jianchao Wang To: axboe@kernel.dk Cc: ming.lei@redhat.com, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH V3 2/4] blk-mq: insert request without involving any io scheduler Date: Mon, 29 Oct 2018 16:33:31 +0800 Message-Id: <1540802013-2921-3-git-send-email-jianchao.w.wang@oracle.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1540802013-2921-1-git-send-email-jianchao.w.wang@oracle.com> References: <1540802013-2921-1-git-send-email-jianchao.w.wang@oracle.com> X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=9060 signatures=668683 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=8.0.1-1807170000 definitions=main-1810290082 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 When try to issue request directly, if the queue is stopped or quiesced, 'bypass_insert' will be ignored and return BLK_STS_OK to caller to avoid it dispatch request again. Then the request will be inserted with blk_mq_sched_insert_request. This is not correct for dm-rq case where we should avoid to pass through the underlying paths' io scheduler. To fix it, use blk_mq_request_bypass_insert to insert the request into hctx->dispatch directly. Signed-off-by: Jianchao Wang --- block/blk-mq.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 0f6328b..e0aa068 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1729,13 +1729,14 @@ static blk_status_t __blk_mq_issue_directly(struct blk_mq_hw_ctx *hctx, } enum mq_decision { + MQ_INSERT_DISPATCH, MQ_INSERT_QUEUE, MQ_END_REQUEST, MQ_DO_NOTHING, }; static inline enum mq_decision - blk_mq_make_dicision(blk_status_t ret, bool bypass_insert) + blk_mq_make_dicision(blk_status_t ret, bool bypass_insert, bool force) { enum mq_decision dec; @@ -1745,7 +1746,10 @@ static inline enum mq_decision break; case BLK_STS_DEV_RESOURCE: case BLK_STS_RESOURCE: - dec = bypass_insert ? MQ_DO_NOTHING : MQ_INSERT_QUEUE; + if (force) + dec = bypass_insert ? MQ_INSERT_DISPATCH : MQ_INSERT_QUEUE; + else + dec = bypass_insert ? MQ_DO_NOTHING : MQ_INSERT_QUEUE; break; default: dec = bypass_insert ? MQ_DO_NOTHING : MQ_END_REQUEST; @@ -1761,7 +1765,7 @@ static blk_status_t blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx, bool bypass_insert) { struct request_queue *q = rq->q; - bool run_queue = true; + bool run_queue = true, force = false; enum mq_decision dec; blk_status_t ret = BLK_STS_RESOURCE; int srcu_idx; @@ -1776,7 +1780,7 @@ static blk_status_t blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx, */ if (blk_mq_hctx_stopped(hctx) || blk_queue_quiesced(q)) { run_queue = false; - bypass_insert = false; + force = true; goto out_unlock; } @@ -1795,8 +1799,11 @@ static blk_status_t blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx, out_unlock: hctx_unlock(hctx, srcu_idx); - dec = blk_mq_make_dicision(ret, bypass_insert); + dec = blk_mq_make_dicision(ret, bypass_insert, force); switch(dec) { + case MQ_INSERT_DISPATCH: + blk_mq_request_bypass_insert(rq, run_queue); + break; case MQ_INSERT_QUEUE: blk_mq_sched_insert_request(rq, false, run_queue, false); break;