From patchwork Tue Nov 13 09:56:52 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "jianchao.wang" X-Patchwork-Id: 10680161 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 6E47513B5 for ; Tue, 13 Nov 2018 09:58:07 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5E0442A28D for ; Tue, 13 Nov 2018 09:58:07 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 523052A2C6; Tue, 13 Nov 2018 09:58:07 +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 DB9312A28D for ; Tue, 13 Nov 2018 09:58:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731762AbeKMTy4 (ORCPT ); Tue, 13 Nov 2018 14:54:56 -0500 Received: from userp2130.oracle.com ([156.151.31.86]:46224 "EHLO userp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731528AbeKMTyz (ORCPT ); Tue, 13 Nov 2018 14:54:55 -0500 Received: from pps.filterd (userp2130.oracle.com [127.0.0.1]) by userp2130.oracle.com (8.16.0.22/8.16.0.22) with SMTP id wAD9sElA017838; Tue, 13 Nov 2018 09:57:32 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=KjtFBzl48kWHUaiGs45dIZaVO/sEyPqGFzaPjx5bZbs=; b=WoPLa08dFh70M75vP5o8Rk+bvqut0yF0Nr5sgjjfvRU+LyckU1JUWhTJjbjAfZkpR9ck kyJ2bf5w5s6u6ZjmS9tYO5/bLUGfs9v0dByABneAci4Z5YDixdUKX8GjCAZszGMShTER FWC/zHPeHxwCSEfi2zKy8YaYOlCK/EgjyhRFF5PR5staPCf37JPGrfQ3Qg3pFLYz33Ac 0uzmyVKbYTLBfZOub/2zsw/qFt3H53hD9ikWnq8IF3NVqJ0BMraX5qMwLlynyRYmCLUM NZNmwmKNpLmawy8IOtYSrflNifv+B3/Ehzajxda7CNThKYSNfh589J0H6KMo3zNN1cb5 0w== Received: from userv0022.oracle.com (userv0022.oracle.com [156.151.31.74]) by userp2130.oracle.com with ESMTP id 2nnwg19fxf-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 13 Nov 2018 09:57:32 +0000 Received: from aserv0122.oracle.com (aserv0122.oracle.com [141.146.126.236]) by userv0022.oracle.com (8.14.4/8.14.4) with ESMTP id wAD9vVtr023568 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 13 Nov 2018 09:57:32 GMT Received: from abhmp0020.oracle.com (abhmp0020.oracle.com [141.146.116.26]) by aserv0122.oracle.com (8.14.4/8.14.4) with ESMTP id wAD9vV1G032358; Tue, 13 Nov 2018 09:57:31 GMT Received: from will-ThinkCentre-M93p.cn.oracle.com (/10.182.70.234) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Tue, 13 Nov 2018 01:57:31 -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 V6 1/5] blk-mq: refactor the code of issue request directly Date: Tue, 13 Nov 2018 17:56:52 +0800 Message-Id: <1542103016-21037-2-git-send-email-jianchao.w.wang@oracle.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1542103016-21037-1-git-send-email-jianchao.w.wang@oracle.com> References: <1542103016-21037-1-git-send-email-jianchao.w.wang@oracle.com> X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=9075 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-1811130093 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 Merge blk_mq_try_issue_directly and __blk_mq_try_issue_directly into one interface to unify the interfaces to issue requests directly. The merged interface takes over the requests totally, it could insert, end or do nothing based on the return value of .queue_rq and 'bypass' parameter. Then caller needn't any other handling any more. Signed-off-by: Jianchao Wang --- block/blk-mq.c | 93 ++++++++++++++++++++++++++++------------------------------ 1 file changed, 45 insertions(+), 48 deletions(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 411be60..14b4d06 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1766,78 +1766,75 @@ static blk_status_t __blk_mq_issue_directly(struct blk_mq_hw_ctx *hctx, return ret; } -static blk_status_t __blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx, +static blk_status_t blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx, struct request *rq, blk_qc_t *cookie, - bool bypass_insert) + bool bypass) { struct request_queue *q = rq->q; bool run_queue = true; + blk_status_t ret = BLK_STS_RESOURCE; + int srcu_idx; + hctx_lock(hctx, &srcu_idx); /* - * RCU or SRCU read lock is needed before checking quiesced flag. + * hctx_lock is needed before checking quiesced flag. * - * When queue is stopped or quiesced, ignore 'bypass_insert' from - * blk_mq_request_issue_directly(), and return BLK_STS_OK to caller, - * and avoid driver to try to dispatch again. + * When queue is stopped or quiesced, ignore 'bypass', insert + * and return BLK_STS_OK to caller, and avoid driver to try to + * dispatch again. */ - if (blk_mq_hctx_stopped(hctx) || blk_queue_quiesced(q)) { + if (unlikely(blk_mq_hctx_stopped(hctx) || blk_queue_quiesced(q))) { run_queue = false; - bypass_insert = false; - goto insert; + bypass = false; + goto out_unlock; } - if (q->elevator && !bypass_insert) - goto insert; + /* + * Bypass the potential scheduler on the bottom device. + */ + if (unlikely(q->elevator && !bypass)) + goto out_unlock; - if (!blk_mq_get_dispatch_budget(hctx)) - goto insert; + if (unlikely(!blk_mq_get_dispatch_budget(hctx))) + goto out_unlock; - if (!blk_mq_get_driver_tag(rq)) { + if (unlikely(!blk_mq_get_driver_tag(rq))) { blk_mq_put_dispatch_budget(hctx); - goto insert; + goto out_unlock; } - return __blk_mq_issue_directly(hctx, rq, cookie); -insert: - if (bypass_insert) - return BLK_STS_RESOURCE; - - blk_mq_sched_insert_request(rq, false, run_queue, false); - return BLK_STS_OK; -} - -static void blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx, - struct request *rq, blk_qc_t *cookie) -{ - blk_status_t ret; - int srcu_idx; - - might_sleep_if(hctx->flags & BLK_MQ_F_BLOCKING); + ret = __blk_mq_issue_directly(hctx, rq, cookie); - hctx_lock(hctx, &srcu_idx); +out_unlock: + hctx_unlock(hctx, srcu_idx); - ret = __blk_mq_try_issue_directly(hctx, rq, cookie, false); - if (ret == BLK_STS_RESOURCE || ret == BLK_STS_DEV_RESOURCE) - blk_mq_sched_insert_request(rq, false, true, false); - else if (ret != BLK_STS_OK) - blk_mq_end_request(rq, ret); + switch (ret) { + case BLK_STS_OK: + break; + case BLK_STS_DEV_RESOURCE: + case BLK_STS_RESOURCE: + if (!bypass) { + blk_mq_sched_insert_request(rq, false, run_queue, false); + ret = BLK_STS_OK; + } + break; + default: + if (!bypass) { + blk_mq_end_request(rq, ret); + ret = BLK_STS_OK; + } + break; + } - hctx_unlock(hctx, srcu_idx); + return ret; } blk_status_t blk_mq_request_issue_directly(struct request *rq) { - blk_status_t ret; - int srcu_idx; blk_qc_t unused_cookie; - struct blk_mq_hw_ctx *hctx = rq->mq_hctx; - hctx_lock(hctx, &srcu_idx); - ret = __blk_mq_try_issue_directly(hctx, rq, &unused_cookie, true); - hctx_unlock(hctx, srcu_idx); - - return ret; + return blk_mq_try_issue_directly(rq->mq_hctx, rq, &unused_cookie, true); } void blk_mq_try_issue_list_directly(struct blk_mq_hw_ctx *hctx, @@ -1958,13 +1955,13 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) if (same_queue_rq) { data.hctx = same_queue_rq->mq_hctx; blk_mq_try_issue_directly(data.hctx, same_queue_rq, - &cookie); + &cookie, false); } } else if ((q->nr_hw_queues > 1 && is_sync) || (!q->elevator && !data.hctx->dispatch_busy)) { blk_mq_put_ctx(data.ctx); blk_mq_bio_to_request(rq, bio); - blk_mq_try_issue_directly(data.hctx, rq, &cookie); + blk_mq_try_issue_directly(data.hctx, rq, &cookie, false); } else { blk_mq_put_ctx(data.ctx); blk_mq_bio_to_request(rq, bio);