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=-8.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,T_DKIMWL_WL_HIGH,UNPARSEABLE_RELAY,USER_AGENT_GIT 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 DE4BDC32789 for ; Fri, 2 Nov 2018 07:10:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A3BFD20831 for ; Fri, 2 Nov 2018 07:10:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="TjIm469n" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A3BFD20831 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 S1728501AbeKBQQb (ORCPT ); Fri, 2 Nov 2018 12:16:31 -0400 Received: from aserp2120.oracle.com ([141.146.126.78]:49894 "EHLO aserp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728223AbeKBQQa (ORCPT ); Fri, 2 Nov 2018 12:16:30 -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 wA279JpJ054289; Fri, 2 Nov 2018 07:10:17 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=vP9NZTogfxTR9G3rvMIz+J5V3m/qpmKyl4aDVJu3Rhg=; b=TjIm469nK6xaJBacIOHBd2Op4nI2dNcGiZtsln/30mE5UNW1hxLT4v5MrEVCo84VvrUZ 4NOrbNHCeR/QAcQOAmc5xwvvEHU0+1DC0QZCI6WmRBtmt7qUXshDbzJHmjmJyh/deVa4 3LV7/NunkfKlBNTVY49mFOdA2FxShpOxK7FD93kPi/hmFBGklMjwD2cwgRxloWVyXZmf tMczZUnHshAVH34bpVFX5sPM8paSoxJ9Z0rgHDKC8PY1eZJr0W7CyGfOtkAtyJfeXbfe lCJyzz/T556TOsKx+VTXIwWyn7Ptlyy89f8S4sy9ZMLjJ3nJOg21QbXCoklRMJcTJCwY TQ== Received: from userv0022.oracle.com (userv0022.oracle.com [156.151.31.74]) by aserp2120.oracle.com with ESMTP id 2ncfyqctvr-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 02 Nov 2018 07:10:17 +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 wA27AGtm019751 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 2 Nov 2018 07:10:16 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 wA27AFN9003253; Fri, 2 Nov 2018 07:10:16 GMT Received: from will-ThinkCentre-M93p.cn.oracle.com (/10.182.70.234) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Fri, 02 Nov 2018 00:10:15 -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 V4 2/5] blk-mq: refactor the code of issue request directly Date: Fri, 2 Nov 2018 15:08:53 +0800 Message-Id: <1541142536-1431-3-git-send-email-jianchao.w.wang@oracle.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1541142536-1431-1-git-send-email-jianchao.w.wang@oracle.com> References: <1541142536-1431-1-git-send-email-jianchao.w.wang@oracle.com> X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=9064 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-1811020067 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Merge blk_mq_try_issue_directly and __blk_mq_try_issue_directly into one interface which is able to handle the return value from .queue_rq callback. To make the code clearer, introduce new helpers enum mq_issue_decision and blk_mq_make_decision to decide how to handle the non-issued requests. Signed-off-by: Jianchao Wang --- block/blk-mq.c | 104 +++++++++++++++++++++++++++++++++------------------------ 1 file changed, 61 insertions(+), 43 deletions(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index af5b591..962fdfc 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1729,78 +1729,96 @@ 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, +enum mq_issue_decision { + MQ_ISSUE_INSERT_QUEUE, + MQ_ISSUE_END_REQUEST, + MQ_ISSUE_DO_NOTHING, +}; + +static inline enum mq_issue_decision + blk_mq_make_dicision(blk_status_t ret, bool bypass) +{ + enum mq_issue_decision dec; + + switch(ret) { + case BLK_STS_OK: + dec = MQ_ISSUE_DO_NOTHING; + break; + case BLK_STS_DEV_RESOURCE: + case BLK_STS_RESOURCE: + dec = bypass ? MQ_ISSUE_DO_NOTHING : MQ_ISSUE_INSERT_QUEUE; + break; + default: + dec = bypass ? MQ_ISSUE_DO_NOTHING : MQ_ISSUE_END_REQUEST; + break; + } + + return dec; +} + +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; + enum mq_issue_decision dec; + 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)) { run_queue = false; - bypass_insert = false; - goto insert; + bypass = false; + goto out_unlock; } - if (q->elevator && !bypass_insert) - goto insert; + if (q->elevator && !bypass) + goto out_unlock; if (!blk_mq_get_dispatch_budget(hctx)) - goto insert; + goto out_unlock; if (!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; + ret = __blk_mq_issue_directly(hctx, rq, cookie); - 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); - - 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) + dec = blk_mq_make_dicision(ret, bypass); + switch(dec) { + case MQ_ISSUE_INSERT_QUEUE: + blk_mq_sched_insert_request(rq, false, run_queue, false); + break; + case MQ_ISSUE_END_REQUEST: blk_mq_end_request(rq, ret); + break; + default: + return ret; + } - hctx_unlock(hctx, srcu_idx); + return BLK_STS_OK; } blk_status_t blk_mq_request_issue_directly(struct request *rq) { - blk_status_t ret; - int srcu_idx; struct blk_mq_ctx *ctx = rq->mq_ctx; struct blk_mq_hw_ctx *hctx = blk_mq_map_queue(rq->q, ctx->cpu); - hctx_lock(hctx, &srcu_idx); - ret = __blk_mq_try_issue_directly(hctx, rq, NULL, true); - hctx_unlock(hctx, srcu_idx); - - return ret; + return blk_mq_try_issue_directly(hctx, rq, NULL, true); } void blk_mq_try_issue_list_directly(struct blk_mq_hw_ctx *hctx, @@ -1922,13 +1940,13 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) data.hctx = blk_mq_map_queue(q, same_queue_rq->mq_ctx->cpu); 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); -- 2.7.4