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=-13.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 EFA19C433E0 for ; Tue, 28 Jul 2020 13:29:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D4F4120759 for ; Tue, 28 Jul 2020 13:29:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729991AbgG1N3z (ORCPT ); Tue, 28 Jul 2020 09:29:55 -0400 Received: from mx2.suse.de ([195.135.220.15]:38378 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729044AbgG1N3y (ORCPT ); Tue, 28 Jul 2020 09:29:54 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 3B832B67A; Tue, 28 Jul 2020 13:30:04 +0000 (UTC) From: Daniel Wagner To: Jens Axboe Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, Daniel Wagner , Ming Lei Subject: [PATCH] block: Use non _rcu version of list functions for tag_set_list Date: Tue, 28 Jul 2020 15:29:51 +0200 Message-Id: <20200728132951.29459-1-dwagner@suse.de> X-Mailer: git-send-email 2.16.4 Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org tag_set_list is only accessed under the tag_set_lock lock. There is no need for using the _rcu list functions. The _rcu list function were introduced to allow read access to the tag_set_list protected under RCU, see 705cda97ee3a ("blk-mq: Make it safe to use RCU to iterate over blk_mq_tag_set.tag_list") and 05b79413946d ("Revert "blk-mq: don't handle TAG_SHARED in restart""). Those changes got reverted later but the cleanup commit missed a couple of places to undo the changes. Fixes: 97889f9ac24f ("blk-mq: remove synchronize_rcu() from blk_mq_del_queue_tag_set()" Cc: Ming Lei Signed-off-by: Daniel Wagner --- block/blk-mq.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index e32cb0217135..14ee7506f32f 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2792,7 +2792,7 @@ static void blk_mq_del_queue_tag_set(struct request_queue *q) struct blk_mq_tag_set *set = q->tag_set; mutex_lock(&set->tag_list_lock); - list_del_rcu(&q->tag_set_list); + list_del(&q->tag_set_list); if (list_is_singular(&set->tag_list)) { /* just transitioned to unshared */ set->flags &= ~BLK_MQ_F_TAG_SHARED; @@ -2819,7 +2819,7 @@ static void blk_mq_add_queue_tag_set(struct blk_mq_tag_set *set, } if (set->flags & BLK_MQ_F_TAG_SHARED) queue_set_hctx_shared(q, true); - list_add_tail_rcu(&q->tag_set_list, &set->tag_list); + list_add_tail(&q->tag_set_list, &set->tag_list); mutex_unlock(&set->tag_list_lock); } -- 2.16.4