From patchwork Fri Sep 18 01:47:05 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yufen Yu X-Patchwork-Id: 11783827 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 34951112E for ; Fri, 18 Sep 2020 01:47:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1CF282137B for ; Fri, 18 Sep 2020 01:47:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726151AbgIRBre (ORCPT ); Thu, 17 Sep 2020 21:47:34 -0400 Received: from szxga05-in.huawei.com ([45.249.212.191]:13249 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726187AbgIRBre (ORCPT ); Thu, 17 Sep 2020 21:47:34 -0400 Received: from DGGEMS410-HUB.china.huawei.com (unknown [172.30.72.59]) by Forcepoint Email with ESMTP id 905CC8BBC7C06C9190FE; Fri, 18 Sep 2020 09:47:31 +0800 (CST) Received: from huawei.com (10.175.101.6) by DGGEMS410-HUB.china.huawei.com (10.3.19.210) with Microsoft SMTP Server id 14.3.487.0; Fri, 18 Sep 2020 09:47:23 +0800 From: Yufen Yu To: CC: , , , Subject: [PATCH 3/4] block: fix comment and add lockdep assert Date: Thu, 17 Sep 2020 21:47:05 -0400 Message-ID: <20200918014706.1962485-4-yuyufen@huawei.com> X-Mailer: git-send-email 2.25.4 In-Reply-To: <20200918014706.1962485-1-yuyufen@huawei.com> References: <20200918014706.1962485-1-yuyufen@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.101.6] X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org After commit b89f625e28d4 ("block: don't release queue's sysfs lock during switching elevator"), whole elevator register and unregister function are covered by sysfs_lock. So, remove wrong comment and add lockdep assert. Signed-off-by: Yufen Yu --- block/elevator.c | 14 ++++---------- 1 file changed, 4 insertions(+), 10 deletions(-) diff --git a/block/elevator.c b/block/elevator.c index 431a2a1c896e..293c5c81397a 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -479,16 +479,13 @@ static struct kobj_type elv_ktype = { .release = elevator_release, }; -/* - * elv_register_queue is called from either blk_register_queue or - * elevator_switch, elevator switch is prevented from being happen - * in the two paths, so it is safe to not hold q->sysfs_lock. - */ int elv_register_queue(struct request_queue *q, bool uevent) { struct elevator_queue *e = q->elevator; int error; + lockdep_assert_held(&q->sysfs_lock); + error = kobject_add(&e->kobj, &q->kobj, "%s", "iosched"); if (!error) { struct elv_fs_entry *attr = e->type->elevator_attrs; @@ -507,13 +504,10 @@ int elv_register_queue(struct request_queue *q, bool uevent) return error; } -/* - * elv_unregister_queue is called from either blk_unregister_queue or - * elevator_switch, elevator switch is prevented from being happen - * in the two paths, so it is safe to not hold q->sysfs_lock. - */ void elv_unregister_queue(struct request_queue *q) { + lockdep_assert_held(&q->sysfs_lock); + if (q) { struct elevator_queue *e = q->elevator;