From patchwork Wed Jul 12 12:54:47 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ming Lei X-Patchwork-Id: 13310332 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 590E0EB64D9 for ; Wed, 12 Jul 2023 12:55:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231520AbjGLMzv (ORCPT ); Wed, 12 Jul 2023 08:55:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34508 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229993AbjGLMzu (ORCPT ); Wed, 12 Jul 2023 08:55:50 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0A0311736 for ; Wed, 12 Jul 2023 05:55:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1689166505; 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=5CYqK3Y+IQKFaUkutdkJlO3sotphYax9MRe0AccKI2w=; b=NMF8elJOLN2B6Ld6/MIgP86eUw2w/r1OG6RR6S3xoOvniErJynIclF4R31wRyUTcy5WITq eMqOJ/QJzm1V8wOHMEDq4itk8IAyRTzhv3Uyh6qR5YC0lNL9G707hJYRvvhyuoH+Z+u3xc MRibskSX69dUCqWd1fGe34m6dg6xJ04= Received: from mimecast-mx02.redhat.com (66.187.233.73 [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-418-PESh_r3nPIO4H1zgny0CSw-1; Wed, 12 Jul 2023 08:55:03 -0400 X-MC-Unique: PESh_r3nPIO4H1zgny0CSw-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.rdu2.redhat.com [10.11.54.8]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 151EB3C0FC99; Wed, 12 Jul 2023 12:55:03 +0000 (UTC) Received: from localhost (ovpn-8-25.pek2.redhat.com [10.72.8.25]) by smtp.corp.redhat.com (Postfix) with ESMTP id E15D3C1ED96; Wed, 12 Jul 2023 12:55:01 +0000 (UTC) From: Ming Lei To: Jens Axboe , Christoph Hellwig , linux-nvme@lists.infradead.org, "Martin K . Petersen" , linux-scsi@vger.kernel.org Cc: linux-block@vger.kernel.org, Wen Xiong , Keith Busch , Ming Lei Subject: [PATCH 0/8] blk-mq: fix wrong queue mapping for kdump kernel Date: Wed, 12 Jul 2023 20:54:47 +0800 Message-Id: <20230712125455.1986455-1-ming.lei@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.8 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Hi, On arm and ppc64, 'maxcpus=1' is required for kdump kernel, see `Documentation/admin-guide/kdump/kdump.rst`, so num_possible_cpus() still returns all CPUs because 'maxcpus=1' just bring up one single cpu core during booting. blk-mq sees single queue in kdump kernel, and in driver's viewpoint there are still multiple queues, this inconsistency causes driver to apply wrong queue mapping for handling IO, and IO timeout is triggered. This issue is only triggered on managed irq in case of multiple hw queues. Some drivers takes online cpus into account for nr_hw_queues, and don't have such issue, such as nvme rdma/tcp. Meantime, single queue makes much less resource utilization, and reduce risk of kernel failure. Thanks, Ming Ming Lei (8): blk-mq: add blk_mq_max_nr_hw_queues() nvme-pci: use blk_mq_max_nr_hw_queues() to calculate io queues scsi: lpfc: use blk_mq_max_nr_hw_queues() to calculate io vectors scsi: hisi: take blk_mq_max_nr_hw_queues() into account for calculating io vectors scsi: mpi3mr: take blk_mq_max_nr_hw_queues() into account for calculating io vectors scsi: megaraid: take blk_mq_max_nr_hw_queues() into account for calculating io vectors scsi: mpt3sas: take blk_mq_max_nr_hw_queues() into account for calculating io vectors scsi: pm8001: take blk_mq_max_nr_hw_queues() into account for calculating io vectors block/blk-mq.c | 9 +++++++++ drivers/nvme/host/pci.c | 2 +- drivers/scsi/hisi_sas/hisi_sas_v3_hw.c | 3 +++ drivers/scsi/lpfc/lpfc_init.c | 1 + drivers/scsi/megaraid/megaraid_sas_base.c | 6 +++++- drivers/scsi/mpi3mr/mpi3mr_fw.c | 3 +++ drivers/scsi/mpt3sas/mpt3sas_base.c | 4 ++-- drivers/scsi/pm8001/pm8001_init.c | 4 +++- include/linux/blk-mq.h | 1 + 9 files changed, 28 insertions(+), 5 deletions(-)