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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F1D36C433F5 for ; Wed, 3 Nov 2021 03:44:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DA1F9610CA for ; Wed, 3 Nov 2021 03:44:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230232AbhKCDqu (ORCPT ); Tue, 2 Nov 2021 23:46:50 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:59073 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229506AbhKCDqu (ORCPT ); Tue, 2 Nov 2021 23:46:50 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1635911054; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=4e1SOw0qm99517HgL8VV+WSt1ycW8ms5ogP7+32Qx68=; b=CTsyV3K07eTsY/AmGngbsSno+74ZQ5EXITUWexKm92xRIvvyVXlM/LBLtNU4QjWpNJhW3u SkWafPbWkHPYj3oT/55sJQhlzrV7kuqwZ2PCmA5HWnSxBWod356iHQhqkvSylnkdMyWWwD wdk+e6NiYKmbHJfRqAY1LkPlYHKSYhY= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-7-1nJ8Rd40PcqfPNNTw9fxzg-1; Tue, 02 Nov 2021 23:44:11 -0400 X-MC-Unique: 1nJ8Rd40PcqfPNNTw9fxzg-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id A5B83871807; Wed, 3 Nov 2021 03:44:09 +0000 (UTC) Received: from localhost (ovpn-8-17.pek2.redhat.com [10.72.8.17]) by smtp.corp.redhat.com (Postfix) with ESMTP id 8F6C55C232; Wed, 3 Nov 2021 03:44:00 +0000 (UTC) From: Ming Lei To: Jens Axboe Cc: Yi Zhang , linux-block@vger.kernel.org, linux-nvme@lists.infradead.org, "Martin K . Petersen" , linux-scsi@vger.kernel.org, James Bottomley , Ming Lei Subject: [PATCH 2/4] scsi: avoid to quiesce sdev->request_queue two times Date: Wed, 3 Nov 2021 11:43:03 +0800 Message-Id: <20211103034305.3691555-3-ming.lei@redhat.com> In-Reply-To: <20211103034305.3691555-1-ming.lei@redhat.com> References: <20211103034305.3691555-1-ming.lei@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org For fixing queue quiesce race between driver and block layer(elevator switch, update nr_requests, ...), we need to support concurrent quiesce and unquiesce, which requires the two to be balanced. blk_mq_quiesce_queue() calls blk_mq_quiesce_queue_nowait() for updating quiesce depth and marking the flag, then scsi_internal_device_block() calls blk_mq_quiesce_queue_nowait() two times actually. Fix the double quiesce and keep quiesce and unquiesce balanced. Reported-by: Yi Zhang Fixes: e70feb8b3e68 ("blk-mq: support concurrent queue quiesce/unquiesce") Signed-off-by: Ming Lei --- drivers/scsi/scsi_lib.c | 29 ++++++++++++++--------------- 1 file changed, 14 insertions(+), 15 deletions(-) diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 9c2b99e12ce3..1cd3ef9056d5 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -2645,6 +2645,14 @@ scsi_target_resume(struct scsi_target *starget) } EXPORT_SYMBOL(scsi_target_resume); +static int __scsi_internal_device_block_nowait(struct scsi_device *sdev) +{ + if (scsi_device_set_state(sdev, SDEV_BLOCK)) + return scsi_device_set_state(sdev, SDEV_CREATED_BLOCK); + + return 0; +} + /** * scsi_internal_device_block_nowait - try to transition to the SDEV_BLOCK state * @sdev: device to block @@ -2661,24 +2669,16 @@ EXPORT_SYMBOL(scsi_target_resume); */ int scsi_internal_device_block_nowait(struct scsi_device *sdev) { - struct request_queue *q = sdev->request_queue; - int err = 0; - - err = scsi_device_set_state(sdev, SDEV_BLOCK); - if (err) { - err = scsi_device_set_state(sdev, SDEV_CREATED_BLOCK); - - if (err) - return err; - } + int ret = __scsi_internal_device_block_nowait(sdev); /* * The device has transitioned to SDEV_BLOCK. Stop the * block layer from calling the midlayer with this device's * request queue. */ - blk_mq_quiesce_queue_nowait(q); - return 0; + if (!ret) + blk_mq_quiesce_queue_nowait(sdev->request_queue); + return ret; } EXPORT_SYMBOL_GPL(scsi_internal_device_block_nowait); @@ -2699,13 +2699,12 @@ EXPORT_SYMBOL_GPL(scsi_internal_device_block_nowait); */ static int scsi_internal_device_block(struct scsi_device *sdev) { - struct request_queue *q = sdev->request_queue; int err; mutex_lock(&sdev->state_mutex); - err = scsi_internal_device_block_nowait(sdev); + err = __scsi_internal_device_block_nowait(sdev); if (err == 0) - blk_mq_quiesce_queue(q); + blk_mq_quiesce_queue(sdev->request_queue); mutex_unlock(&sdev->state_mutex); return err; -- 2.31.1