From patchwork Mon Sep 13 15:12:17 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Garry X-Patchwork-Id: 12489627 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=-11.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,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 75198C4332F for ; Mon, 13 Sep 2021 15:17:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5AE2560FE6 for ; Mon, 13 Sep 2021 15:17:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346099AbhIMPSq (ORCPT ); Mon, 13 Sep 2021 11:18:46 -0400 Received: from frasgout.his.huawei.com ([185.176.79.56]:3772 "EHLO frasgout.his.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345577AbhIMPSm (ORCPT ); Mon, 13 Sep 2021 11:18:42 -0400 Received: from fraeml745-chm.china.huawei.com (unknown [172.18.147.206]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4H7VQt12R9z67yyT; Mon, 13 Sep 2021 23:15:18 +0800 (CST) Received: from lhreml724-chm.china.huawei.com (10.201.108.75) by fraeml745-chm.china.huawei.com (10.206.15.226) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.8; Mon, 13 Sep 2021 17:17:22 +0200 Received: from localhost.localdomain (10.69.192.58) by lhreml724-chm.china.huawei.com (10.201.108.75) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.8; Mon, 13 Sep 2021 16:17:20 +0100 From: John Garry To: CC: , , , , John Garry Subject: [PATCH RESEND v3 00/13] blk-mq: Reduce static requests memory footprint for shared sbitmap Date: Mon, 13 Sep 2021 23:12:17 +0800 Message-ID: <1631545950-56586-1-git-send-email-john.garry@huawei.com> X-Mailer: git-send-email 2.8.1 MIME-Version: 1.0 X-Originating-IP: [10.69.192.58] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To lhreml724-chm.china.huawei.com (10.201.108.75) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Currently a full set of static requests are allocated per hw queue per tagset when shared sbitmap is used. However, only tagset->queue_depth number of requests may be active at any given time. As such, only tagset->queue_depth number of static requests are required. The same goes for using an IO scheduler, which allocates a full set of static requests per hw queue per request queue. This series changes shared sbitmap support by using a shared tags per tagset and request queue. Ming suggested something along those lines in v1 review. But we'll keep name "shared sbitmap" name as it is familiar. In using a shared tags, the static rqs also become shared, reducing the number of sets of static rqs, reducing memory usage. Patch "blk-mq: Use shared tags for shared sbitmap support" is a bit big, and could potentially be broken down. But then maintaining ability to bisect becomes harder and each sub-patch would get more convoluted. For megaraid sas driver on my 128-CPU arm64 system with 1x SATA disk, we save approx. 300MB(!) [370MB -> 60MB] Baseline is v5.15-rc1 This resend is just a rebase, which applied cleanly. Changes since v2: - Make blk_mq_clear_rq_mapping() static again - Various function renaming for conciseness and consistency - Add/refactor alloc/free map and rqs function - Drop the new blk_mq_ops init_request method in favour of passing an invalid HW queue index for shared sbitmap - Add patch to not clear rq mapping for driver tags - Remove blk_mq_init_bitmap_tags() - Add some more RB tags (thanks!) Changes since v1: - Switch to use blk_mq_tags for shared sbitmap - Add new blk_mq_ops init request callback - Add some RB tags (thanks!) John Garry (13): blk-mq: Change rqs check in blk_mq_free_rqs() block: Rename BLKDEV_MAX_RQ -> BLKDEV_DEFAULT_RQ blk-mq: Relocate shared sbitmap resize in blk_mq_update_nr_requests() blk-mq: Invert check in blk_mq_update_nr_requests() blk-mq-sched: Rename blk_mq_sched_alloc_{tags -> map_and_rqs}() blk-mq-sched: Rename blk_mq_sched_free_{requests -> rqs}() blk-mq: Pass driver tags to blk_mq_clear_rq_mapping() blk-mq: Don't clear driver tags own mapping blk-mq: Add blk_mq_tag_update_sched_shared_sbitmap() blk-mq: Add blk_mq_alloc_map_and_rqs() blk-mq: Refactor and rename blk_mq_free_map_and_{requests->rqs}() blk-mq: Use shared tags for shared sbitmap support blk-mq: Stop using pointers for blk_mq_tags bitmap tags block/bfq-iosched.c | 4 +- block/blk-core.c | 4 +- block/blk-mq-debugfs.c | 8 +- block/blk-mq-sched.c | 116 +++++++++++------------ block/blk-mq-sched.h | 4 +- block/blk-mq-tag.c | 125 +++++++++--------------- block/blk-mq-tag.h | 14 +-- block/blk-mq.c | 209 ++++++++++++++++++++++++----------------- block/blk-mq.h | 18 ++-- block/blk.h | 2 +- block/kyber-iosched.c | 4 +- block/mq-deadline.c | 2 +- drivers/block/rbd.c | 2 +- include/linux/blk-mq.h | 15 ++- include/linux/blkdev.h | 5 +- 15 files changed, 256 insertions(+), 276 deletions(-)