From mboxrd@z Thu Jan 1 00:00:00 1970 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E9049C433F5 for ; Wed, 29 Sep 2021 04:17:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CC55D613D1 for ; Wed, 29 Sep 2021 04:17:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232244AbhI2ESt (ORCPT ); Wed, 29 Sep 2021 00:18:49 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:60884 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232353AbhI2ESt (ORCPT ); Wed, 29 Sep 2021 00:18:49 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1632889028; 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: in-reply-to:in-reply-to:references:references; bh=78Fsgf1h+RTfDgrnE/nQEe6tYqMqnM7d0kWUC6K8lx0=; b=FVDt8sF7IevfrineaYGRIMVADFvHgYqbbaEOrP4siljWMIlP/kiBALrqHbVSNMriedx1ok I/kZwxTzmt5LbQ6s/BAQ1kk5rmB9w01oFYgrFSM/RLACKet2ahmQs7W233JXo50hgGZzBu oLSbG8H4bbToWUI/MZn2PFjElweZsZU= 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-39-V4ec62t6MJq9enBSN7ieYg-1; Wed, 29 Sep 2021 00:17:06 -0400 X-MC-Unique: V4ec62t6MJq9enBSN7ieYg-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 117C5802921; Wed, 29 Sep 2021 04:17:05 +0000 (UTC) Received: from localhost (ovpn-8-18.pek2.redhat.com [10.72.8.18]) by smtp.corp.redhat.com (Postfix) with ESMTP id 6CE6A5C1D5; Wed, 29 Sep 2021 04:16:56 +0000 (UTC) From: Ming Lei To: Jens Axboe , Christoph Hellwig , linux-block@vger.kernel.org Cc: Sagi Grimberg , linux-nvme@lists.infradead.org, Keith Busch , Ming Lei Subject: [PATCH 4/5] nvme: paring quiesce/unquiesce Date: Wed, 29 Sep 2021 12:15:58 +0800 Message-Id: <20210929041559.701102-5-ming.lei@redhat.com> In-Reply-To: <20210929041559.701102-1-ming.lei@redhat.com> References: <20210929041559.701102-1-ming.lei@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org The current blk_mq_quiesce_queue() and blk_mq_unquiesce_queue() always stops and starts the queue unconditionally. And there can be concurrent quiesce/unquiesce coming from different unrelated code paths, so unquiesce may come unexpectedly and start queue too early. Prepare for supporting nested / concurrent quiesce/unquiesce, so that we can address the above issue. NVMe has very complicated quiesce/unquiesce use pattern, add one mutex and queue stopped state in nvme_ctrl, so that we can make sure that quiece/unquiesce is called in pair. Signed-off-by: Ming Lei --- drivers/nvme/host/core.c | 51 ++++++++++++++++++++++++++++++++++++---- drivers/nvme/host/nvme.h | 4 ++++ 2 files changed, 50 insertions(+), 5 deletions(-) diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index 23fb746a8970..5d0b2eb38e43 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -4375,6 +4375,7 @@ int nvme_init_ctrl(struct nvme_ctrl *ctrl, struct device *dev, clear_bit(NVME_CTRL_FAILFAST_EXPIRED, &ctrl->flags); spin_lock_init(&ctrl->lock); mutex_init(&ctrl->scan_lock); + mutex_init(&ctrl->queues_stop_lock); INIT_LIST_HEAD(&ctrl->namespaces); xa_init(&ctrl->cels); init_rwsem(&ctrl->namespaces_rwsem); @@ -4450,14 +4451,44 @@ int nvme_init_ctrl(struct nvme_ctrl *ctrl, struct device *dev, } EXPORT_SYMBOL_GPL(nvme_init_ctrl); +static void __nvme_stop_admin_queue(struct nvme_ctrl *ctrl) +{ + lockdep_assert_held(&ctrl->queues_stop_lock); + + if (!ctrl->admin_queue_stopped) { + blk_mq_quiesce_queue(ctrl->admin_q); + ctrl->admin_queue_stopped = true; + } +} + +static void __nvme_start_admin_queue(struct nvme_ctrl *ctrl) +{ + lockdep_assert_held(&ctrl->queues_stop_lock); + + if (ctrl->admin_queue_stopped) { + blk_mq_unquiesce_queue(ctrl->admin_q); + ctrl->admin_queue_stopped = false; + } +} + static void nvme_start_ns_queue(struct nvme_ns *ns) { - blk_mq_unquiesce_queue(ns->queue); + lockdep_assert_held(&ns->ctrl->queues_stop_lock); + + if (test_bit(NVME_NS_STOPPED, &ns->flags)) { + blk_mq_unquiesce_queue(ns->queue); + clear_bit(NVME_NS_STOPPED, &ns->flags); + } } static void nvme_stop_ns_queue(struct nvme_ns *ns) { - blk_mq_quiesce_queue(ns->queue); + lockdep_assert_held(&ns->ctrl->queues_stop_lock); + + if (!test_bit(NVME_NS_STOPPED, &ns->flags)) { + blk_mq_quiesce_queue(ns->queue); + set_bit(NVME_NS_STOPPED, &ns->flags); + } } /* @@ -4490,16 +4521,18 @@ void nvme_kill_queues(struct nvme_ctrl *ctrl) { struct nvme_ns *ns; + mutex_lock(&ctrl->queues_stop_lock); down_read(&ctrl->namespaces_rwsem); /* Forcibly unquiesce queues to avoid blocking dispatch */ if (ctrl->admin_q && !blk_queue_dying(ctrl->admin_q)) - nvme_start_admin_queue(ctrl); + __nvme_start_admin_queue(ctrl); list_for_each_entry(ns, &ctrl->namespaces, list) nvme_set_queue_dying(ns); up_read(&ctrl->namespaces_rwsem); + mutex_unlock(&ctrl->queues_stop_lock); } EXPORT_SYMBOL_GPL(nvme_kill_queues); @@ -4555,10 +4588,12 @@ void nvme_stop_queues(struct nvme_ctrl *ctrl) { struct nvme_ns *ns; + mutex_lock(&ctrl->queues_stop_lock); down_read(&ctrl->namespaces_rwsem); list_for_each_entry(ns, &ctrl->namespaces, list) nvme_stop_ns_queue(ns); up_read(&ctrl->namespaces_rwsem); + mutex_unlock(&ctrl->queues_stop_lock); } EXPORT_SYMBOL_GPL(nvme_stop_queues); @@ -4566,22 +4601,28 @@ void nvme_start_queues(struct nvme_ctrl *ctrl) { struct nvme_ns *ns; + mutex_lock(&ctrl->queues_stop_lock); down_read(&ctrl->namespaces_rwsem); list_for_each_entry(ns, &ctrl->namespaces, list) nvme_start_ns_queue(ns); up_read(&ctrl->namespaces_rwsem); + mutex_unlock(&ctrl->queues_stop_lock); } EXPORT_SYMBOL_GPL(nvme_start_queues); void nvme_stop_admin_queue(struct nvme_ctrl *ctrl) { - blk_mq_quiesce_queue(ctrl->admin_q); + mutex_lock(&ctrl->queues_stop_lock); + __nvme_stop_admin_queue(ctrl); + mutex_unlock(&ctrl->queues_stop_lock); } EXPORT_SYMBOL_GPL(nvme_stop_admin_queue); void nvme_start_admin_queue(struct nvme_ctrl *ctrl) { - blk_mq_unquiesce_queue(ctrl->admin_q); + mutex_lock(&ctrl->queues_stop_lock); + __nvme_start_admin_queue(ctrl); + mutex_unlock(&ctrl->queues_stop_lock); } EXPORT_SYMBOL_GPL(nvme_start_admin_queue); diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h index 47877a5f1515..3a02a370f025 100644 --- a/drivers/nvme/host/nvme.h +++ b/drivers/nvme/host/nvme.h @@ -341,6 +341,9 @@ struct nvme_ctrl { struct page *discard_page; unsigned long discard_page_busy; + bool admin_queue_stopped; + struct mutex queues_stop_lock; + struct nvme_fault_inject fault_inject; }; @@ -457,6 +460,7 @@ struct nvme_ns { #define NVME_NS_ANA_PENDING 2 #define NVME_NS_FORCE_RO 3 #define NVME_NS_READY 4 +#define NVME_NS_STOPPED 5 struct cdev cdev; struct device cdev_device; -- 2.31.1