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=-11.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 6049AC433DB for ; Wed, 3 Feb 2021 11:16:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1C06964DDB for ; Wed, 3 Feb 2021 11:16:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234092AbhBCLPz (ORCPT ); Wed, 3 Feb 2021 06:15:55 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:50662 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234045AbhBCLPp (ORCPT ); Wed, 3 Feb 2021 06:15:45 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1612350859; 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=Oy4LdHHhpcx8PkVqXHlcQAPSxvy9bZPhze5Lo5BjGU4=; b=BC+E1T1VJ2/MdIkH8YZzaDZxz1EPvr7akvPbZ+/HPIenGpJHfc+DBar+BcfBaxYE4ut+NW IcEKOn/HwxasS5PQ6hDCkyCngjLvfVjZ9IPBQJKBsjtBAtXMrCp+F3rNtTlp66Wi4LaI2o 0WYd6N5c5gHTuaWGqf9BQdKRLDXp4Pk= 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-296-fHbtCcwgNbitdbPL1jypsg-1; Wed, 03 Feb 2021 06:14:18 -0500 X-MC-Unique: fHbtCcwgNbitdbPL1jypsg-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 8AA47DF8A7; Wed, 3 Feb 2021 11:14:16 +0000 (UTC) Received: from T590 (ovpn-12-143.pek2.redhat.com [10.72.12.143]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 1ECC93828; Wed, 3 Feb 2021 11:14:07 +0000 (UTC) Date: Wed, 3 Feb 2021 19:14:02 +0800 From: Ming Lei To: "Martin K. Petersen" Cc: Jens Axboe , linux-block@vger.kernel.org, linux-scsi@vger.kernel.org, Omar Sandoval , Kashyap Desai , Sumanesh Samanta , "Ewan D . Milne" , Hannes Reinecke Subject: Re: [PATCH V7 00/13] blk-mq/scsi: tracking device queue depth via sbitmap Message-ID: <20210203111402.GA1065845@T590> References: <20210122023317.687987-1-ming.lei@redhat.com> <20210131115245.GA1979183@T590> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Hi Martin, On Mon, Feb 01, 2021 at 05:33:52PM -0500, Martin K. Petersen wrote: > > Ming, > > > BTW, which tree are you based for applying this patchset? > > 5.12/scsi-queue > > > I apply the patchset against for-5.12/block, and run it on kvm with > > 'megasas' device(LSI MegaRAID SAS 1078), looks it works well, and not > > see the hang issue. > > I tried with for-5.12/block and it still breaks for me. Things work fine > up until: > > scsi: core: Replace sdev->device_busy with sbitmap > > After that patch is applied no disks are discovered on my SAS/FC hosts. I think the following patch should fix the issue, care to give a test? diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 7d9171e05b58..65807cac6228 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -1266,7 +1266,10 @@ static inline int scsi_dev_queue_ready(struct request_queue *q, token = sbitmap_get(&sdev->budget_map); if (atomic_read(&sdev->device_blocked)) { - if (token >= 0) + if (token < 0) + goto out; + + if (scsi_device_busy(sdev) > 1) goto out_dec; /* @@ -1282,6 +1285,7 @@ static inline int scsi_dev_queue_ready(struct request_queue *q, out_dec: if (token >= 0) sbitmap_put(&sdev->budget_map, token); +out: return -1; } -- Ming