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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 484C7ECAAA2 for ; Fri, 26 Aug 2022 01:27:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244449AbiHZB1L (ORCPT ); Thu, 25 Aug 2022 21:27:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53622 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244409AbiHZB1J (ORCPT ); Thu, 25 Aug 2022 21:27:09 -0400 Received: from out30-57.freemail.mail.aliyun.com (out30-57.freemail.mail.aliyun.com [115.124.30.57]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 50ABEA7225; Thu, 25 Aug 2022 18:27:02 -0700 (PDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R491e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018045168;MF=liusong@linux.alibaba.com;NM=1;PH=DS;RN=3;SR=0;TI=SMTPD_---0VNGOONg_1661477190; Received: from localhost(mailfrom:liusong@linux.alibaba.com fp:SMTPD_---0VNGOONg_1661477190) by smtp.aliyun-inc.com; Fri, 26 Aug 2022 09:27:00 +0800 From: Liu Song To: axboe@kernel.dk Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] blk-mq: determine in advance whether batch alloc can be performed Date: Fri, 26 Aug 2022 09:26:30 +0800 Message-Id: <1661477190-86862-1-git-send-email-liusong@linux.alibaba.com> X-Mailer: git-send-email 1.8.3.1 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org From: Liu Song Some conditions for judging whether batch alloc can be performed are included in "blk_mq_get_tags", and this function is only used by "__blk_mq_alloc_requests_batch". This patch introduced a helper "can_do_batch_alloc" to prepend the judgment condition and avoid unnecessary function calls. Signed-off-by: Liu Song --- block/blk-mq-tag.c | 3 --- block/blk-mq.c | 11 ++++++++++- 2 files changed, 10 insertions(+), 4 deletions(-) diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c index 8e3b36d..cda3987 100644 --- a/block/blk-mq-tag.c +++ b/block/blk-mq-tag.c @@ -115,9 +115,6 @@ unsigned long blk_mq_get_tags(struct blk_mq_alloc_data *data, int nr_tags, struct sbitmap_queue *bt = &tags->bitmap_tags; unsigned long ret; - if (data->shallow_depth ||data->flags & BLK_MQ_REQ_RESERVED || - data->hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED) - return 0; ret = __sbitmap_queue_get_batch(bt, nr_tags, offset); *offset += tags->nr_reserved_tags; return ret; diff --git a/block/blk-mq.c b/block/blk-mq.c index 3c1e6b6..330c618 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -437,6 +437,15 @@ static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data, return rq_list_pop(data->cached_rq); } +static inline bool can_do_batch_alloc(struct blk_mq_alloc_data *data) +{ + if (data->nr_tags > 1 && !(data->shallow_depth || + data->flags & BLK_MQ_REQ_RESERVED || + data->hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED)) + return true; + return false; +} + static struct request *__blk_mq_alloc_requests(struct blk_mq_alloc_data *data) { struct request_queue *q = data->q; @@ -480,7 +489,7 @@ static struct request *__blk_mq_alloc_requests(struct blk_mq_alloc_data *data) /* * Try batched alloc if we want more than 1 tag. */ - if (data->nr_tags > 1) { + if (can_do_batch_alloc(data)) { rq = __blk_mq_alloc_requests_batch(data, alloc_time_ns); if (rq) return rq; -- 1.8.3.1