From patchwork Wed Sep 26 21:01:02 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bart Van Assche X-Patchwork-Id: 10616813 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 7CCCD174A for ; Wed, 26 Sep 2018 21:01:39 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6D29F2B801 for ; Wed, 26 Sep 2018 21:01:39 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 6B15A2B865; Wed, 26 Sep 2018 21:01:39 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.7 required=2.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6DF9B2B86A for ; Wed, 26 Sep 2018 21:01:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726727AbeI0DQZ (ORCPT ); Wed, 26 Sep 2018 23:16:25 -0400 Received: from out002.mailprotect.be ([83.217.72.86]:38457 "EHLO out002.mailprotect.be" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726107AbeI0DQZ (ORCPT ); Wed, 26 Sep 2018 23:16:25 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=mailprotect.be; s=mail; h=Content-Transfer-Encoding:MIME-Version:Message-Id :Date:Subject:Cc:To:From:reply-to:sender:bcc:in-reply-to:references: content-type; bh=+2Js1X/q45lEh+TGxQaVa25vNPyF8DA33QXsmsr+apA=; b=bS1yJt8ZssP8 TTKPa0k6PzfY2wr4AF9SmssQfs/Jo4yxXl/rLTLv+dQR+vCbSe6tIe3+p+sXAtPVicTpn+XapcFam h9zrfMkabtP7qqgf1XF7RCCMLaII3l1IbpVVHhrj0n8g6DbV/Iyu2RmuvUoJz5S+5iEjJzzEhSq7N mfvbvvTnVxx7wHYn4Nj5AvkelhuDr8GLYGPQJWKMT9Q5H0Tsmwa3K2ZiiKxn1jGtvcQ27LpV0I1Pr e3VMl6mbW6VCj0B+oN3jsVdnVOJTjGEULrqSAaBHu1cJ5cRHy1Zhkw3c2+L9LE3oGxDX1E1snbLW/ J3hp6hMiAfn9KWBqDGal4g==; Received: from smtp-auth.mailprotect.be ([178.208.39.159]) by com-mpt-out002.mailprotect.be with esmtp (Exim 4.89) (envelope-from ) id 1g5Gw9-000BlP-Gu; Wed, 26 Sep 2018 23:01:34 +0200 Received: from desktop-bart.svl.corp.google.com (unknown [104.133.8.89]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp-auth.mailprotect.be (Postfix) with ESMTPSA id BC317C0361; Wed, 26 Sep 2018 23:01:17 +0200 (CEST) From: Bart Van Assche To: Jens Axboe Cc: linux-block@vger.kernel.org, Christoph Hellwig , Bart Van Assche Subject: [PATCH v11 0/8] blk-mq: Implement runtime power management Date: Wed, 26 Sep 2018 14:01:02 -0700 Message-Id: <20180926210110.20362-1-bvanassche@acm.org> X-Mailer: git-send-email 2.19.0.605.g01d371f741-goog MIME-Version: 1.0 X-Originating-IP: 178.208.39.159 X-SpamExperts-Domain: mailprotect.be X-SpamExperts-Username: 178.208.39.128/27 Authentication-Results: mailprotect.be; auth=pass smtp.auth=178.208.39.128/27@mailprotect.be X-SpamExperts-Outgoing-Class: ham X-SpamExperts-Outgoing-Evidence: Combined (0.05) X-Recommended-Action: accept X-Filter-ID: EX5BVjFpneJeBchSMxfU5g9O/IyjeFfZmeEv1m+c/Bd602E9L7XzfQH6nu9C/Fh9KJzpNe6xgvOx q3u0UDjvO1tLifGj39bI0bcPyaJsYTaOqZpfO3PVJjdazu3l6Zm3CrxbKqqxVb1b/D8J7mjn9lDh ZuDehiH2YklRjLmWtDSmAEYI57h2mKAXM6QK99xqZOFbSD3u8HyLgGOQKCi94YeKZwfB8hlkn+RD yVPdu0/ilbHtbFYVmmyNP/jzd7CC6hBx0MWsIqDBZyeY119Okv3hl8yPfPdsT0UPQvdnVMOU8Zf+ B9qSJPzSsfZHWcrk0wiB5Hyfbd+MEJoOqabVUmvDy59pzP1iosV0DNWOAjtKmgPibyDvE1NrkqBr j5LVTAHvvK3wzc9xtICtqPlcxdKelFAlBm05iz5amJ7IrkWDVBIlfDzdqrCMCxk4PGeKWG7kK39p Pgyq7MfSXQHW36gux18SgkjQE1RDgqlo3I0LAao5RzCtd/nkTxNvxuZerjIfxK2tug+mEO2au1ST CTIzJvw9qxD5zQLggp7fQffzn6lW1kGYXc7LzqBLOOMBIK/1NH5THMtlYvyHAYGOGgjdb5hy4d8/ k+RlvkD7ATmoZ2kfng5rdXwjvpU4S+XAhVR1id1GLKHJBvyjlI1w1OhVceCu6itH4YpfzgAUZzko cSk62AlAgqFHvPoJ+2PmpQPYWZCscE5IQENYCi1G6UCc0RxCf9FkbFgnW+3iFcf0oNABzQxwob1u +dNdIjp/ccBbl1BHkCySY+bm8ly/DcLFbWytmZzGUc1tNu77kJRQazMn6WLsmpwGaTF7LH61QGmn /0s7yNORlJsMuxx5wjMyPubo19ws1mc9j52p1Wu/paDZu9BYXptV3Ba+EWiA7mO7tb9j5FCrlct0 NDRE/+HQ8cQ5+hWV5O0279/I1JPrjuU3A3io6xJmD59iFVkb+AU6q1UwDsMQCbPquATGabyZS7Sc T75RjnQYc6HoKp6uedK/Z3MvnAyDmuOaA5CG/FxvddG4mRHKJlnoc+LvLMw4Oh2LkwsmIC+tUiJA U2G2XhkGbmsUNPNkere1WheN5NhD8uPe57LIJ6DJCG96zHB7HfKjI1eYNYaA4ur2/Is= X-Report-Abuse-To: spam@com-mpt-mgt001.mailprotect.be Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Hello Jens, One of the pieces that is missing before blk-mq can be made the default is implementing runtime power management support for blk-mq. This patch series not only implements runtime power management for blk-mq but also fixes a starvation issue in the power management code for the legacy block layer. Please consider this patch series for the upstream kernel. Thanks, Bart. Changes compared to v10: - Added a comment in the percpu-refcount patch in this series as Tejun asked. - Updated Acked-by / Reviewed-by tags. Changes compared to v9: - Left out the patches that document the functions that iterate over requests and also the patch that introduces blk_mq_queue_rq_iter(). - Simplified blk_pre_runtime_suspend(): left out the check whether no requests are in progress. - Fixed the race between blk_queue_enter(), queue freezing and runtime power management that Ming had identified. - Added a new patch that introduces percpu_ref_resurrect(). Changes compared to v8: - Fixed the race that was reported by Jianchao. - Fixed another spelling issue in a source code comment. Changes compared to v7: - Addressed Jianchao's feedback about patch "Make blk_get_request() block for non-PM requests while suspended". - Added two new patches - one that documents the functions that iterate over requests and one that introduces a new function that iterates over all requests associated with a queue. Changes compared to v6: - Left out the patches that split RQF_PREEMPT in three flags. - Left out the patch that introduces the SCSI device state SDEV_SUSPENDED. - Left out the patch that introduces blk_pm_runtime_exit(). - Restored the patch that changes the PREEMPT_ONLY flag into a counter. Changes compared to v5: - Introduced a new flag RQF_DV that replaces RQF_PREEMPT for SCSI domain validation. - Introduced a new request queue state QUEUE_FLAG_DV_ONLY for SCSI domain validation. - Instead of using SDEV_QUIESCE for both runtime suspend and SCSI domain validation, use that state for domain validation only and introduce a new state for runtime suspend, namely SDEV_QUIESCE. - Reallow system suspend during SCSI domain validation. - Moved the runtime resume call from the request allocation code into blk_queue_enter(). - Instead of relying on q_usage_counter, iterate over the tag set to determine whether or not any requests are in flight. Changes compared to v4: - Dropped the patches "Give RQF_PREEMPT back its original meaning" and "Serialize queue freezing and blk_pre_runtime_suspend()". - Replaced "percpu_ref_read()" with "percpu_is_in_use()". - Inserted pm_request_resume() calls in the block layer request allocation code such that the context that submits a request no longer has to call pm_runtime_get(). Changes compared to v3: - Avoid adverse interactions between system-wide suspend/resume and runtime power management by changing the PREEMPT_ONLY flag into a counter. - Give RQF_PREEMPT back its original meaning, namely that it is only set for ide_preempt requests. - Remove the flag BLK_MQ_REQ_PREEMPT. - Removed the pm_request_resume() call. Changes compared to v2: - Fixed the build for CONFIG_BLOCK=n. - Added a patch that introduces percpu_ref_read() in the percpu-counter code. - Added a patch that makes it easier to detect missing pm_runtime_get*() calls. - Addressed Jianchao's feedback including the comment about runtime overhead of switching a per-cpu counter to atomic mode. Changes compared to v1: - Moved the runtime power management code into a separate file. - Addressed Ming's feedback. Bart Van Assche (8): block: Move power management code into a new source file block, scsi: Change the preempt-only flag into a counter block: Split blk_pm_add_request() and blk_pm_put_request() block: Schedule runtime resume earlier percpu-refcount: Introduce percpu_ref_resurrect() block: Allow unfreezing of a queue while requests are in progress block: Make blk_get_request() block for non-PM requests while suspended blk-mq: Enable support for runtime power management block/Kconfig | 3 + block/Makefile | 1 + block/blk-core.c | 270 ++++---------------------------- block/blk-mq-debugfs.c | 10 +- block/blk-mq.c | 4 +- block/blk-pm.c | 216 +++++++++++++++++++++++++ block/blk-pm.h | 69 ++++++++ block/elevator.c | 22 +-- drivers/scsi/scsi_lib.c | 11 +- drivers/scsi/scsi_pm.c | 1 + drivers/scsi/sd.c | 1 + drivers/scsi/sr.c | 1 + include/linux/blk-pm.h | 24 +++ include/linux/blkdev.h | 37 ++--- include/linux/percpu-refcount.h | 1 + lib/percpu-refcount.c | 28 +++- 16 files changed, 401 insertions(+), 298 deletions(-) create mode 100644 block/blk-pm.c create mode 100644 block/blk-pm.h create mode 100644 include/linux/blk-pm.h