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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 96167C4332F for ; Fri, 21 Oct 2022 01:14:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=x0x7La/KJwWUwTRhdc113nlLBaY7LHMOa3RNzKxynnI=; b=sNuKCB+CcPItQBb5zF59yONc3Q U1ce9Aqlg9i8+dWjV7x/v4jaqT7B+/N69yi7blFFZOEydVvRiPbJ61YThAiEUzv07XWlf2PUDwk1P zG6ZYawHgQ2M1x2/j924MW9cTzn0BsrYXCW5VAH1Izzi2DWZaQHBGz4yzjJFkTH4K8187FDawTW/r vGibS87thOJ10XGYDKowWd4mpmqqsadoaxQR2loL+n/WvsbQDwcZICLdUMv0Ua5RF2RT787D9wicS ursPG1LWH21G3uPdXhUCTW3RKwrnBR/mTe89qt7+6Rw5rWXjZA6PmHFuMXidqwqqvJz4YewNJ37J+ CAMkK6yw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1olgbp-003QdC-UH; Fri, 21 Oct 2022 01:14:01 +0000 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1olgbn-003Qba-BK for linux-nvme@lists.infradead.org; Fri, 21 Oct 2022 01:14:00 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1666314838; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=x0x7La/KJwWUwTRhdc113nlLBaY7LHMOa3RNzKxynnI=; b=hhxpfZMrfULYMogzmjHj3YnjUvzwuZBgGlEIsbOJVYzyPt0jUPdooaSdjAE+VyIFDyMv2g 0U4nV+kN6BMN7a7f5Z+CNZVeGi75QVfGkAIwxtP/+djPySrS9OGTuWRkU/NpvVio7Ad6DS r8LBrqVLvQlwj8lI4rwFsfaXJt4PwbU= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-148-eDA5xFHcP06FD__MNwUdQg-1; Thu, 20 Oct 2022 21:13:54 -0400 X-MC-Unique: eDA5xFHcP06FD__MNwUdQg-1 Received: from smtp.corp.redhat.com (int-mx10.intmail.prod.int.rdu2.redhat.com [10.11.54.10]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 69E14800186; Fri, 21 Oct 2022 01:13:48 +0000 (UTC) Received: from T590 (ovpn-8-24.pek2.redhat.com [10.72.8.24]) by smtp.corp.redhat.com (Postfix) with ESMTPS id A7486426205; Fri, 21 Oct 2022 01:13:36 +0000 (UTC) Date: Fri, 21 Oct 2022 09:13:29 +0800 From: Ming Lei To: Christoph Hellwig Cc: Jens Axboe , Keith Busch , Sagi Grimberg , Chao Leng , linux-nvme@lists.infradead.org, linux-block@vger.kernel.org Subject: Re: [PATCH 2/8] blk-mq: skip non-mq queues in blk_mq_quiesce_queue Message-ID: References: <20221020105608.1581940-1-hch@lst.de> <20221020105608.1581940-3-hch@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20221020105608.1581940-3-hch@lst.de> X-Scanned-By: MIMEDefang 3.1 on 10.11.54.10 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221020_181359_474511_997B4298 X-CRM114-Status: GOOD ( 20.38 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On Thu, Oct 20, 2022 at 12:56:02PM +0200, Christoph Hellwig wrote: > For submit_bio based queues there is no (S)RCU critical section during > I/O submission and thus nothing to wait for in blk_mq_wait_quiesce_done, > so skip doing any synchronization. > > Signed-off-by: Christoph Hellwig > --- > block/blk-mq.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/block/blk-mq.c b/block/blk-mq.c > index 33292c01875d5..df967c8af9fee 100644 > --- a/block/blk-mq.c > +++ b/block/blk-mq.c > @@ -280,7 +280,9 @@ EXPORT_SYMBOL_GPL(blk_mq_wait_quiesce_done); > void blk_mq_quiesce_queue(struct request_queue *q) > { > blk_mq_quiesce_queue_nowait(q); > - blk_mq_wait_quiesce_done(q); > + /* nothing to wait for non-mq queues */ > + if (queue_is_mq(q)) > + blk_mq_wait_quiesce_done(q); This interface can't work as expected for bio drivers, the only user should be del_gendisk(), but anyway the patch is fine: Reviewed-by: Ming Lei thanks, Ming