From patchwork Wed May 31 12:37:04 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ming Lei X-Patchwork-Id: 9756815 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id ED1DE60390 for ; Wed, 31 May 2017 12:38:46 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id DA449283C4 for ; Wed, 31 May 2017 12:38:46 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id CC72F283FF; Wed, 31 May 2017 12:38:46 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6FFDB283C4 for ; Wed, 31 May 2017 12:38:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751161AbdEaMii (ORCPT ); Wed, 31 May 2017 08:38:38 -0400 Received: from mx1.redhat.com ([209.132.183.28]:38216 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751038AbdEaMih (ORCPT ); Wed, 31 May 2017 08:38:37 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 5F55C2D9FC6; Wed, 31 May 2017 12:38:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 5F55C2D9FC6 Authentication-Results: ext-mx06.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx06.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=ming.lei@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 5F55C2D9FC6 Received: from localhost (ovpn-12-119.pek2.redhat.com [10.72.12.119]) by smtp.corp.redhat.com (Postfix) with ESMTP id 190AE51C69; Wed, 31 May 2017 12:38:25 +0000 (UTC) From: Ming Lei To: Jens Axboe , linux-block@vger.kernel.org, Christoph Hellwig Cc: Bart Van Assche , Ming Lei Subject: [PATCH v3 7/9] blk-mq: don't stop queue for quiescing Date: Wed, 31 May 2017 20:37:04 +0800 Message-Id: <20170531123706.20885-8-ming.lei@redhat.com> In-Reply-To: <20170531123706.20885-1-ming.lei@redhat.com> References: <20170531123706.20885-1-ming.lei@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.30]); Wed, 31 May 2017 12:38:37 +0000 (UTC) Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Queue can be started by other blk-mq APIs and can be used in different cases, this limits uses of blk_mq_quiesce_queue() if it is based on stopping queue, and make its usage very difficult, especially users have to use the stop queue APIs carefully for avoiding to break blk_mq_quiesce_queue(). We have applied the QUIESCED flag for draining and blocking dispatch, so it isn't necessary to stop queue any more. After stopping queue is removed, blk_mq_quiesce_queue() can be used safely and easily, then users won't worry about queue restarting during quiescing at all. Signed-off-by: Ming Lei --- block/blk-mq.c | 4 ---- 1 file changed, 4 deletions(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 1faddaf005e2..bcff1b184bbb 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -169,8 +169,6 @@ void blk_mq_quiesce_queue(struct request_queue *q) unsigned int i; bool rcu = false; - __blk_mq_stop_hw_queues(q, true); - spin_lock_irq(q->queue_lock); queue_flag_set(QUEUE_FLAG_QUIESCED, q); spin_unlock_irq(q->queue_lock); @@ -199,8 +197,6 @@ void blk_mq_unquiesce_queue(struct request_queue *q) queue_flag_clear(QUEUE_FLAG_QUIESCED, q); spin_unlock_irq(q->queue_lock); - blk_mq_start_stopped_hw_queues(q, true); - wake_up_all(&q->quiesce_wq); } EXPORT_SYMBOL_GPL(blk_mq_unquiesce_queue);