From patchwork Tue Dec 1 21:29:41 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mike Christie X-Patchwork-Id: 11943845 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=-10.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,USER_AGENT_GIT 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 A7D75C83013 for ; Tue, 1 Dec 2020 21:31:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5158C2085B for ; Tue, 1 Dec 2020 21:31:20 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="zpUeM56E" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729454AbgLAVbE (ORCPT ); Tue, 1 Dec 2020 16:31:04 -0500 Received: from userp2130.oracle.com ([156.151.31.86]:46718 "EHLO userp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729347AbgLAVbD (ORCPT ); Tue, 1 Dec 2020 16:31:03 -0500 Received: from pps.filterd (userp2130.oracle.com [127.0.0.1]) by userp2130.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 0B1LTN7a018840; Tue, 1 Dec 2020 21:30:12 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : subject : date : message-id; s=corp-2020-01-29; bh=7EgUkcoHKcec2MRQDgbuTkzcavb0i9ajumZYYK+MyDo=; b=zpUeM56E2dvusRAKcSjlaeX7Jc4Wvz5Ljfq26TO3a4hah62HXdHCruELgeVj8mIHCwFf rUtBfgKsisr/71cdtg7j+V+O66KuyJ1uzI13qv+8a3ou0LZiZN1O0jKRtyfyrgzn1L3h q7CXWaVSr+mwzGnt1L3crOv/dWEa5EPhNsf5zumaLsq6+IClDjxAz7XE8cmaFDJQRGEI 7nk4xIZVbfSl7IZRBMFFdrqc0YJ8xf66m2X17yak0ws3hxdCdwsR74NGkYySVkXE//sN qd1q1KNsLjAof+U9M2K4eFpIYgj5LOAKEGfWKC+JVj51arOrEXAvUwP21drEwbXEVewI SA== Received: from aserp3020.oracle.com (aserp3020.oracle.com [141.146.126.70]) by userp2130.oracle.com with ESMTP id 353dyqmy25-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Tue, 01 Dec 2020 21:30:12 +0000 Received: from pps.filterd (aserp3020.oracle.com [127.0.0.1]) by aserp3020.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 0B1LU7oA105721; Tue, 1 Dec 2020 21:30:11 GMT Received: from aserv0122.oracle.com (aserv0122.oracle.com [141.146.126.236]) by aserp3020.oracle.com with ESMTP id 3540eyh8tk-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 01 Dec 2020 21:30:11 +0000 Received: from abhmp0017.oracle.com (abhmp0017.oracle.com [141.146.116.23]) by aserv0122.oracle.com (8.14.4/8.14.4) with ESMTP id 0B1LU4Dg020956; Tue, 1 Dec 2020 21:30:09 GMT Received: from ol2.localdomain (/73.88.28.6) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Tue, 01 Dec 2020 13:30:04 -0800 From: Mike Christie To: subbu.seetharaman@broadcom.com, ketan.mukadam@broadcom.com, jitendra.bhivare@broadcom.com, lduncan@suse.com, cleech@redhat.com, njavali@marvell.com, mrangankar@marvell.com, GR-QLogic-Storage-Upstream@marvell.com, varun@chelsio.com, martin.petersen@oracle.com, linux-scsi@vger.kernel.org, james.bottomley@hansenpartnership.com Subject: [RFC PATCH 00/15] libiscsi: lock clean ups Date: Tue, 1 Dec 2020 15:29:41 -0600 Message-Id: <1606858196-5421-1-git-send-email-michael.christie@oracle.com> X-Mailer: git-send-email 1.8.3.1 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9822 signatures=668682 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxscore=0 malwarescore=0 phishscore=0 suspectscore=0 bulkscore=0 spamscore=0 adultscore=0 mlxlogscore=999 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2012010130 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9822 signatures=668682 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 malwarescore=0 bulkscore=0 clxscore=1015 mlxscore=0 spamscore=0 priorityscore=1501 mlxlogscore=999 suspectscore=0 lowpriorityscore=0 phishscore=0 adultscore=0 impostorscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2012010130 Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org The following patches made over Linus's current tree cleanup the locking in libiscsi so we again, for the main IO path, have the frwd lock only used in the xmit/queue path and the back lock used in the completion path and no taskqueuelock. The EH paths still use both the frwd/back lock though. These patches are not ready for merging. I have only tested iscsi_tcp. Also, even though the changes to the offload drivers look like minimal API use changes, I wanted to try and get some tests done as the changes affect the main IO and error paths. Also, I wanted to try and track down any offload maintainers that are still doing development on their drivers. After this batch of patches is merged we can go one step further and remove the frwd lock from queuecommand for at least the iscsi xmit wq based drivers by switching to some per task locking or lllists. And if we can figure out if the offload cards manage their own cmdsn window then we could drop the frwd lock for them too and we could do some optimizatons with the back lock for them.