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=-3.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, 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 B8334C65BAE for ; Fri, 14 Dec 2018 01:29:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 739E52075B for ; Fri, 14 Dec 2018 01:29:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="j0glL3we" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 739E52075B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=oracle.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728920AbeLNB31 (ORCPT ); Thu, 13 Dec 2018 20:29:27 -0500 Received: from userp2120.oracle.com ([156.151.31.85]:42992 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728811AbeLNB3Y (ORCPT ); Thu, 13 Dec 2018 20:29:24 -0500 Received: from pps.filterd (userp2120.oracle.com [127.0.0.1]) by userp2120.oracle.com (8.16.0.22/8.16.0.22) with SMTP id wBE1Ofu6158695; Fri, 14 Dec 2018 01:29:21 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id; s=corp-2018-07-02; bh=JPT9cM6aCRThbzpbJrmOUw+5N4eXdYrAZJTlOqeaoEg=; b=j0glL3werKZRY3tCu1OnIMivG+OWeuPwl2qwuN3hsjVQvkWV0knYE3OaMThAMgmAxCSq YjC0pXeHazOQQpAYpIbPvSxvurUnWe+HKkYHoZ2VQi62NAEL6v9StxhRpvJFX1nwZ03m UrBnLxKa/xoJ5IctrCxUHfxdsZ3TbGd9C0X8KJUsa1V9bzqD+S3VAlAiAUKZMp0uhdld WZDXYYWdfX13C8edX4DF83QZr7cmwXpxnhj79t8vBSowedzldfpBBmJkeZwbv8Qb0BYn MK+t81xJpYcUy9F7sSokK9KdthSX4j+2SROfWkk0WnP1mwF/JECbJ7jN0xBJ6HXfhEc9 5Q== Received: from aserv0021.oracle.com (aserv0021.oracle.com [141.146.126.233]) by userp2120.oracle.com with ESMTP id 2pb7tf77kf-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 14 Dec 2018 01:29:21 +0000 Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by aserv0021.oracle.com (8.14.4/8.14.4) with ESMTP id wBE1TFW3012813 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 14 Dec 2018 01:29:15 GMT Received: from abhmp0013.oracle.com (abhmp0013.oracle.com [141.146.116.19]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id wBE1TEQd012304; Fri, 14 Dec 2018 01:29:15 GMT Received: from will-ThinkCentre-M93p.cn.oracle.com (/10.182.70.234) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 13 Dec 2018 17:29:14 -0800 From: Jianchao Wang To: axboe@kernel.dk Cc: ming.lei@redhat.com, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH V14 0/3] blk-mq: refactor and fix the code of issue directly Date: Fri, 14 Dec 2018 09:28:17 +0800 Message-Id: <1544750900-1549-1-git-send-email-jianchao.w.wang@oracle.com> X-Mailer: git-send-email 2.7.4 X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=9106 signatures=668679 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=1 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1812140011 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Jens After commit c616cbee ( blk-mq: punt failed direct issue to dispatch list ), we always insert request to hctx dispatch list whenever get a BLK_STS_RESOURCE or BLK_STS_DEV_RESOURCE, this is overkill and will harm the merging. We just need to do that for the requests that has been through .queue_rq. This patch set fixes the issue above and refactors the code of issue request directly to unify the interface and make the code clearer and more readable. Please consider this patchset for 4.21. The 1st patch refactors the code of issue request directly to unify the helper interface which could handle all the cases. And also it does more reasonable decision about how to insert the requests. The 2nd patch make blk_mq_sched_insert_requests issue requests directly with 'bypass' false, then it needn't to handle the non-issued requests any more. The 3rd patch replace and kill the blk_mq_request_issue_directly. V14: - change some comment V13: - remove the unused tag 'out' (1/3) V12: - remove the original 1st patch/ - rebase other 3 patches on newest for-4.21/block - add some comment V11: - insert request to dispatch list when .queue_rq return BLK_STS_RESOURCE/BLK_STS_DEV_RESOURCE. (2/4) - stop to attempt direct-issue and insert the reset when meet non-ok case (3/4). V10: - address Jen's comment. - let blk_mq_try_issue_directly return actual result for case 'bypass == false'. (2/4) - use return value of blk_mq_try_issue_directly to identify whether the request is direct-issued successfully. (3/4) V9: - rebase on recent for-4.21/block - add 1st patch V8: - drop the original 2nd patch which try to insert requests into hctx->dispatch if quiesced or stopped. - remove two wrong 'unlikely' V7: - drop the original 3rd patch which try to ensure hctx to be ran on its mapped cpu in issueing directly path. V6: - drop original 1st patch to address Jen's comment - discard the enum mq_issue_decision and blk_mq_make_decision and use BLK_STS_* return values directly to address Jen's comment. (1/5) - add 'unlikely' in blk_mq_try_issue_directly (1/5) - refactor the 2nd and 3rd patch based on the new 1st patch. - reserve the unused_cookie in 4th and 5th patch V5: - rebase against Jens' for-4.21/block branch - adjust the order of patch04 and patch05 - add patch06 to replace and kill the one line blk_mq_request_bypass_insert - comment changes V4: - split the original patch 1 into two patches, 1st and 2nd patch currently - rename the mq_decision to mq_issue_decision - comment changes V3: - Correct the code about the case bypass_insert is true and io scheduler attached. The request still need to be issued in case above. (1/4) - Refactor the code to make code clearer. blk_mq_make_request is introduced to decide insert, end or just return based on the return value of .queue_rq and bypass_insert (1/4) - Add the 2nd patch. It introduce a new decision result which indicates to insert request with blk_mq_request_bypass_insert. - Modify the code to adapt the new patch 1. V2: - Add 1st and 2nd patch to refactor the code. Jianchao Wang (3) blk-mq: refactor the code of issue request directly blk-mq: issue directly with bypass 'false' in blk-mq: replace and kill blk_mq_request_issue_directly block/blk-core.c | 4 +++- block/blk-mq-sched.c | 8 +++---- block/blk-mq.c | 122 ++++++++++++++++++++++++++++++++++++++++++++++++--------------------------------------------------- block/blk-mq.h | 6 +++-- 4 files changed, 69 insertions(+), 71 deletions(-) Thanks Jianchao