From mboxrd@z Thu Jan 1 00:00:00 1970 From: keith.busch@intel.com (Keith Busch) Date: Wed, 30 Dec 2015 10:27:49 -0700 Subject: [PATCH 3/5] NVMe: Remove queue freezing on resets In-Reply-To: <1451496471-29370-1-git-send-email-keith.busch@intel.com> References: <1451496471-29370-1-git-send-email-keith.busch@intel.com> Message-ID: <1451496471-29370-4-git-send-email-keith.busch@intel.com> NVMe submits all commands through the block layer now. This means we can let requests queue at the blk-mq hardware context since there is no path that bypasses this anymore. This means we don't need to freeze the queues anymore and simply stop the h/w queues from running during a reset. This also fixes a WARN in percpu_ref_reinit when the queue was unfrozen with requeued requests. Signed-off-by: Keith Busch --- drivers/nvme/host/pci.c | 15 ++++++--------- 1 file changed, 6 insertions(+), 9 deletions(-) diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index 3abcb3a..6fb65d4 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -1064,7 +1064,7 @@ static int nvme_suspend_queue(struct nvme_queue *nvmeq) spin_unlock_irq(&nvmeq->q_lock); if (!nvmeq->qid && nvmeq->dev->ctrl.admin_q) - blk_mq_freeze_queue_start(nvmeq->dev->ctrl.admin_q); + blk_mq_stop_hw_queues(nvmeq->dev->ctrl.admin_q); irq_set_affinity_hint(vector, NULL); free_irq(vector, nvmeq); @@ -1291,7 +1291,7 @@ static int nvme_alloc_admin_tags(struct nvme_dev *dev) return -ENODEV; } } else - blk_mq_unfreeze_queue(dev->ctrl.admin_q); + blk_mq_start_stopped_hw_queues(dev->ctrl.admin_q, true); return 0; } @@ -1903,13 +1903,11 @@ static void nvme_dev_list_remove(struct nvme_dev *dev) kthread_stop(tmp); } -static void nvme_freeze_queues(struct nvme_dev *dev) +static void nvme_stop_queues(struct nvme_dev *dev) { struct nvme_ns *ns; list_for_each_entry(ns, &dev->ctrl.namespaces, list) { - blk_mq_freeze_queue_start(ns->queue); - spin_lock_irq(ns->queue->queue_lock); queue_flag_set(QUEUE_FLAG_STOPPED, ns->queue); spin_unlock_irq(ns->queue->queue_lock); @@ -1919,13 +1917,12 @@ static void nvme_freeze_queues(struct nvme_dev *dev) } } -static void nvme_unfreeze_queues(struct nvme_dev *dev) +static void nvme_start_queues(struct nvme_dev *dev) { struct nvme_ns *ns; list_for_each_entry(ns, &dev->ctrl.namespaces, list) { queue_flag_clear_unlocked(QUEUE_FLAG_STOPPED, ns->queue); - blk_mq_unfreeze_queue(ns->queue); blk_mq_start_stopped_hw_queues(ns->queue, true); blk_mq_kick_requeue_list(ns->queue); } @@ -1940,7 +1937,7 @@ static void nvme_dev_shutdown(struct nvme_dev *dev) mutex_lock(&dev->shutdown_lock); if (dev->bar) { - nvme_freeze_queues(dev); + nvme_stop_queues(dev); csts = readl(dev->bar + NVME_REG_CSTS); } if (csts & NVME_CSTS_CFS || !(csts & NVME_CSTS_RDY)) { @@ -2049,7 +2046,7 @@ static void nvme_reset_work(struct work_struct *work) dev_warn(dev->dev, "IO queues not created\n"); nvme_remove_namespaces(&dev->ctrl); } else { - nvme_unfreeze_queues(dev); + nvme_start_queues(dev); nvme_dev_add(dev); } -- 2.6.2.307.g37023ba