From patchwork Wed Sep 23 01:33:27 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ming Lei X-Patchwork-Id: 11793691 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 14DA71668 for ; Wed, 23 Sep 2020 01:34:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ECB6E2371F for ; Wed, 23 Sep 2020 01:33:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Wokdz69e" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726757AbgIWBd7 (ORCPT ); Tue, 22 Sep 2020 21:33:59 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:24051 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726685AbgIWBd6 (ORCPT ); Tue, 22 Sep 2020 21:33:58 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1600824837; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=WZsa2J1lbITIf4ZEunkyJeKTHGH9lL5atd3ZfUlUbVE=; b=Wokdz69ep7ZlMKp6YJ7zRaMwV5UL5WbVH+kFfNwB3Uyd7qw8totpmDPE0rYCsIuIRH+nRI vB0HAnywTK4EqPXsVCDHK+ogNDCXLpSIfAkTkTcAKr6JxEHjaFdtJ67gn8ZXu6LNmOq3DJ nyan/2Yw5nXFBP/UjZIoAuEYzo0RP7w= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-159-raePR-ECPwe0fp_E-AQzfQ-1; Tue, 22 Sep 2020 21:33:53 -0400 X-MC-Unique: raePR-ECPwe0fp_E-AQzfQ-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 792A81074641; Wed, 23 Sep 2020 01:33:51 +0000 (UTC) Received: from localhost (ovpn-12-168.pek2.redhat.com [10.72.12.168]) by smtp.corp.redhat.com (Postfix) with ESMTP id F234F614F5; Wed, 23 Sep 2020 01:33:46 +0000 (UTC) From: Ming Lei To: Jens Axboe , linux-block@vger.kernel.org, "Martin K . Petersen" , linux-scsi@vger.kernel.org Cc: Ming Lei , Omar Sandoval , Kashyap Desai , Sumanesh Samanta , "Ewan D . Milne" , Hannes Reinecke Subject: [PATCH V3 for 5.11 00/12] blk-mq/scsi: tracking device queue depth via sbitmap Date: Wed, 23 Sep 2020 09:33:27 +0800 Message-Id: <20200923013339.1621784-1-ming.lei@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org Hi, scsi uses one global atomic variable to track queue depth for each LUN/request queue. This way can't scale well when there is lots of CPU cores and the disk is very fast. Broadcom guys has complained that their high end HBA can't reach top performance because .device_busy is operated in IO path. Replace the atomic variable sdev->device_busy with sbitmap for tracking scsi device queue depth. Test on scsi_debug shows this way improve IOPS > 20%. Meantime the IOPS difference is just ~1% compared with bypassing .device_busy on scsi_debug via patches[1] The 1st 6 patches moves percpu allocation hint into sbitmap, since the improvement by doing percpu allocation hint on sbitmap is observable. Meantime export helpers for SCSI. Patch 7 and 8 prepares for the conversion by returning budget token from .get_budget callback, meantime passes the budget token to driver via 'struct blk_mq_queue_data' in .queue_rq(). The last four patches changes SCSI for switching to track device queue depth via sbitmap. The patchset have been tested by Broadcom, and obvious performance boost can be observed. Given it is based on both for-5.10/block and 5.10/scsi-queue, the target is for v5.11. And it is posted out just for getting full/enough review. Please comment and review! V3: - rebase on both for-5.10/block and 5.10/scsi-queue. V2: - fix one build failure Ming Lei (12): sbitmap: remove sbitmap_clear_bit_unlock sbitmap: maintain allocation round_robin in sbitmap sbitmap: add helpers for updating allocation hint sbitmap: move allocation hint into sbitmap sbitmap: export sbitmap_weight sbitmap: add helper of sbitmap_calculate_shift blk-mq: add callbacks for storing & retrieving budget token blk-mq: return budget token from .get_budget callback scsi: put hot fields of scsi_host_template into one cacheline scsi: add scsi_device_busy() to read sdev->device_busy scsi: make sure sdev->queue_depth is <= shost->can_queue scsi: replace sdev->device_busy with sbitmap block/blk-mq-sched.c | 17 ++- block/blk-mq.c | 38 +++-- block/blk-mq.h | 25 +++- block/kyber-iosched.c | 3 +- drivers/message/fusion/mptsas.c | 2 +- drivers/scsi/mpt3sas/mpt3sas_scsih.c | 2 +- drivers/scsi/scsi.c | 4 + drivers/scsi/scsi_lib.c | 69 ++++++--- drivers/scsi/scsi_priv.h | 1 + drivers/scsi/scsi_scan.c | 22 ++- drivers/scsi/scsi_sysfs.c | 4 +- drivers/scsi/sg.c | 2 +- include/linux/blk-mq.h | 13 +- include/linux/sbitmap.h | 84 +++++++---- include/scsi/scsi_cmnd.h | 2 + include/scsi/scsi_device.h | 8 +- include/scsi/scsi_host.h | 72 ++++----- lib/sbitmap.c | 213 +++++++++++++++------------ 18 files changed, 376 insertions(+), 205 deletions(-) Cc: Omar Sandoval Cc: Kashyap Desai Cc: Sumanesh Samanta Cc: Ewan D. Milne Cc: Hannes Reinecke Tested-by: Sumanesh Samanta