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=-0.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY autolearn=no 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 594E5CA9EA0 for ; Fri, 18 Oct 2019 21:46:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 28FF920700 for ; Fri, 18 Oct 2019 21:46:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="Bkuzr4nW" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2403776AbfJRVqe (ORCPT ); Fri, 18 Oct 2019 17:46:34 -0400 Received: from aserp2120.oracle.com ([141.146.126.78]:34462 "EHLO aserp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2394511AbfJRVqe (ORCPT ); Fri, 18 Oct 2019 17:46:34 -0400 Received: from pps.filterd (aserp2120.oracle.com [127.0.0.1]) by aserp2120.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x9ILhumN080377; Fri, 18 Oct 2019 21:44:50 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=to : cc : subject : from : references : date : in-reply-to : message-id : mime-version : content-type; s=corp-2019-08-05; bh=2F0XOCRHLUkak6GPRfTWsz3EwXt23ecGMafjjNpfWYY=; b=Bkuzr4nW/kSxEKqbOyYc4twMeEEHIV97OiiQE1jCMyYnZLuundyJTBEcaTAs1oKF0xtc buQ+3GM5YgMa5Z6PVV8IK/X1CxKaGOgos/ZjltgjjG7FjxGmp6sG9QP5aumZLIaCDBCu ukQSfuY44MNgZy0bNo/ndLvfVfDxe5iK+LutSfgr+g61jL1PS09lpiHBedqs3l+b5C7u D1mk+nAIcToi7HtaxVWN70Qy/7TZSKuUz4vzs+5BCg/nOtUbdncTSKEGkLXIBHhHmD19 IQgOmCjG74RZnJdf2nA3FkwuMU3y1PMIDUmTbPLE00P1KoZISxLxa1NuORNtsxVaqypU Cg== Received: from aserp3020.oracle.com (aserp3020.oracle.com [141.146.126.70]) by aserp2120.oracle.com with ESMTP id 2vq0q468pn-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 18 Oct 2019 21:44:49 +0000 Received: from pps.filterd (aserp3020.oracle.com [127.0.0.1]) by aserp3020.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x9ILhBvi070410; Fri, 18 Oct 2019 21:44:49 GMT Received: from userv0122.oracle.com (userv0122.oracle.com [156.151.31.75]) by aserp3020.oracle.com with ESMTP id 2vq0eewhur-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 18 Oct 2019 21:44:49 +0000 Received: from abhmp0009.oracle.com (abhmp0009.oracle.com [141.146.116.15]) by userv0122.oracle.com (8.14.4/8.14.4) with ESMTP id x9ILilhD006030; Fri, 18 Oct 2019 21:44:47 GMT Received: from ca-mkp.ca.oracle.com (/10.159.214.123) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Fri, 18 Oct 2019 21:44:47 +0000 To: Hannes Reinecke Cc: "Martin K. Petersen" , Christoph Hellwig , James Bottomley , linux-scsi@vger.kernel.org, Hannes Reinecke Subject: Re: [PATCH] scsi_dh_alua: Do not run STPG for implicit ALUA From: "Martin K. Petersen" Organization: Oracle Corporation References: <20191018135537.69462-1-hare@suse.de> Date: Fri, 18 Oct 2019 17:44:44 -0400 In-Reply-To: <20191018135537.69462-1-hare@suse.de> (Hannes Reinecke's message of "Fri, 18 Oct 2019 15:55:37 +0200") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1.92 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9414 signatures=668684 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=947 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1910180191 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9414 signatures=668684 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1910180191 Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org Hannes, > If a target only supports implicit ALUA sending a SET TARGET PORT > GROUPS command is not only pointless, but might actually cause issues. We already have a conditional in alua_stpg(): if (!(pg->tpgs & TPGS_MODE_EXPLICIT)) { /* Only implicit ALUA supported, retry */ return SCSI_DH_RETRY; } > @@ -832,6 +832,10 @@ static void alua_rtpg_work(struct work_struct *work) > if (err != SCSI_DH_OK) > pg->flags &= ~ALUA_PG_RUN_STPG; > } > + /* Do not run STPG if only implicit ALUA is supported */ > + if (scsi_device_tpgs(sdev) == TPGS_MODE_IMPLICIT) > + pg->flags &= ~ALUA_PG_RUN_STPG; > + > if (pg->flags & ALUA_PG_RUN_STPG) { > pg->flags &= ~ALUA_PG_RUN_STPG; > spin_unlock_irqrestore(&pg->lock, flags); Instead of checking for EXPLICIT one place and checking for !IMPLICIT another, can we consolidate the two and maybe do: if (pg->flags & ALUA_PG_RUN_STPG && scsi_device_tpgs(sdev) == TPGS_MODE_EXPLICIT) { [...] and then remove the redundant check in alua_stpg()? -- Martin K. Petersen Oracle Linux Engineering