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=-7.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 6A35AC432BE for ; Mon, 23 Aug 2021 08:51:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 430856102A for ; Mon, 23 Aug 2021 08:51:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235680AbhHWIwd (ORCPT ); Mon, 23 Aug 2021 04:52:33 -0400 Received: from frasgout.his.huawei.com ([185.176.79.56]:3678 "EHLO frasgout.his.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235643AbhHWIwa (ORCPT ); Mon, 23 Aug 2021 04:52:30 -0400 Received: from fraeml745-chm.china.huawei.com (unknown [172.18.147.207]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4GtQtc0Jvbz67nHL; Mon, 23 Aug 2021 16:50:32 +0800 (CST) Received: from lhreml724-chm.china.huawei.com (10.201.108.75) by fraeml745-chm.china.huawei.com (10.206.15.226) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.8; Mon, 23 Aug 2021 10:51:43 +0200 Received: from [10.47.87.96] (10.47.87.96) by lhreml724-chm.china.huawei.com (10.201.108.75) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.8; Mon, 23 Aug 2021 09:51:43 +0100 Subject: Re: [PATCH v2 10/11] blk-mq: Use shared tags for shared sbitmap support To: Ming Lei CC: "axboe@kernel.dk" , "jejb@linux.ibm.com" , "martin.petersen@oracle.com" , "linux-block@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-scsi@vger.kernel.org" , "kashyap.desai@broadcom.com" , "hare@suse.de" References: <1628519378-211232-1-git-send-email-john.garry@huawei.com> <1628519378-211232-11-git-send-email-john.garry@huawei.com> From: John Garry Message-ID: Date: Mon, 23 Aug 2021 09:55:44 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.12.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8"; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.47.87.96] X-ClientProxiedBy: lhreml719-chm.china.huawei.com (10.201.108.70) To lhreml724-chm.china.huawei.com (10.201.108.75) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 18/08/2021 09:16, Ming Lei wrote: >> ret = blk_mq_alloc_rqs(set, tags, 0, set->queue_depth); >> + if (ret) { >> + blk_mq_exit_sched_shared_sbitmap(queue); >> + return ret; > There are two such patterns for allocate rq map and request pool > together, please put them into one helper(such as blk_mq_alloc_map_and_rqs) > which can return the allocated tags and handle failure inline. Also we may > convert current users into this helper. > >> } Hi Ming, Do you have a preference for the API: int blk_mq_alloc_map_and_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags **tags, unsigned int hctx_idx, unsigned int depth); void blk_mq_free_map_and_requests(struct blk_mq_tag_set *set, struct blk_mq_tags **tags, unsigned int hctx_idx); or struct blk_mq_tags *blk_mq_alloc_map_and_rqs(struct blk_mq_tag_set *set, unsigned int hctx_idx, unsigned int depth); void blk_mq_free_map_and_requests(struct blk_mq_tag_set *set, struct blk_mq_tags *tags, unsigned int hctx_idx); The advantage of the first is that we don't need the pattern: blk_mq_free_map_and_requests(tags) tags = NULL; But then passing struct blk_mq_tags ** is a bit overly complicated. Thanks, John