From patchwork Wed Jul 26 09:40:18 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ming Lei X-Patchwork-Id: 707467 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 3AEF6C001E0 for ; Wed, 26 Jul 2023 09:41:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233184AbjGZJld (ORCPT ); Wed, 26 Jul 2023 05:41:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57966 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233057AbjGZJl3 (ORCPT ); Wed, 26 Jul 2023 05:41:29 -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 28552B6 for ; Wed, 26 Jul 2023 02:40:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1690364440; 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=qw3JY1fSFkCDbqzWrwPQL1ow2KshJKSV3fmVfeQPZXE=; b=Is3rzyZ00VZyex6RIhnuxWFXO4BhOy/XG4U9/Fx3lxpsHBLeMgc/WHUaWk4TvTR1ptYfZd SR2t3aIeu9AagHmv1uIzBLg7rC9s+jQAIzdH15iNjC5XxEDeHewBXGPrWwcuB7k5mq16hx TSIECs8NYpl10ASUVjvKR5Yry2pXeEk= 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-208-nPty-3TXN5CPhkgu8OlO_A-1; Wed, 26 Jul 2023 05:40:36 -0400 X-MC-Unique: nPty-3TXN5CPhkgu8OlO_A-1 Received: from smtp.corp.redhat.com (int-mx10.intmail.prod.int.rdu2.redhat.com [10.11.54.10]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 2AB713C01BA1; Wed, 26 Jul 2023 09:40:36 +0000 (UTC) Received: from localhost (unknown [10.72.120.4]) by smtp.corp.redhat.com (Postfix) with ESMTP id C90C0492C13; Wed, 26 Jul 2023 09:40:34 +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 V2 0/9] blk-mq: fix wrong queue mapping for kdump kernel Date: Wed, 26 Jul 2023 17:40:18 +0800 Message-Id: <20230726094027.535126-1-ming.lei@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.10 Precedence: bulk List-ID: X-Mailing-List: linux-scsi@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. V2: - add helper of scsi_max_nr_hw_queues() for avoiding potential build failure because scsi driver often doesn't deal with blk-mq directly - apply scsi_max_nr_hw_queues() for all scsi changes - move lpfc's change into managed irq code path Thanks, Ming Ming Lei (9): blk-mq: add blk_mq_max_nr_hw_queues() nvme-pci: use blk_mq_max_nr_hw_queues() to calculate io queues scsi: core: add helper of scsi_max_nr_hw_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 | 16 ++++++++++++++++ drivers/nvme/host/pci.c | 2 +- drivers/scsi/hisi_sas/hisi_sas_v3_hw.c | 3 +++ drivers/scsi/lpfc/lpfc_init.c | 2 ++ 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 + include/scsi/scsi_host.h | 5 +++++ 10 files changed, 41 insertions(+), 5 deletions(-)