NVMe: Remove queue freezing on resets

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 so we don't need to freeze the queues
anymore. The driver can simply stop the h/w queues from running during
a reset instead.

This also fixes a WARN in percpu_ref_reinit when the queue was unfrozen
with requeued requests.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This commit is contained in:
Keith Busch 2016-01-04 09:10:57 -07:00 committed by Jens Axboe
parent 1d49c38c48
commit 25646264e1
3 changed files with 8 additions and 11 deletions

View file

@ -1372,14 +1372,12 @@ int nvme_init_ctrl(struct nvme_ctrl *ctrl, struct device *dev,
return ret;
}
void nvme_freeze_queues(struct nvme_ctrl *ctrl)
void nvme_stop_queues(struct nvme_ctrl *ctrl)
{
struct nvme_ns *ns;
mutex_lock(&ctrl->namespaces_mutex);
list_for_each_entry(ns, &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);
@ -1390,14 +1388,13 @@ void nvme_freeze_queues(struct nvme_ctrl *ctrl)
mutex_unlock(&ctrl->namespaces_mutex);
}
void nvme_unfreeze_queues(struct nvme_ctrl *ctrl)
void nvme_start_queues(struct nvme_ctrl *ctrl)
{
struct nvme_ns *ns;
mutex_lock(&ctrl->namespaces_mutex);
list_for_each_entry(ns, &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);
}

View file

@ -238,8 +238,8 @@ int nvme_init_identify(struct nvme_ctrl *ctrl);
void nvme_scan_namespaces(struct nvme_ctrl *ctrl);
void nvme_remove_namespaces(struct nvme_ctrl *ctrl);
void nvme_freeze_queues(struct nvme_ctrl *ctrl);
void nvme_unfreeze_queues(struct nvme_ctrl *ctrl);
void nvme_stop_queues(struct nvme_ctrl *ctrl);
void nvme_start_queues(struct nvme_ctrl *ctrl);
struct request *nvme_alloc_request(struct request_queue *q,
struct nvme_command *cmd, unsigned int flags);

View file

@ -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);
@ -1296,7 +1296,7 @@ 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;
}
@ -1917,7 +1917,7 @@ static void nvme_dev_shutdown(struct nvme_dev *dev)
mutex_lock(&dev->shutdown_lock);
if (dev->bar) {
nvme_freeze_queues(&dev->ctrl);
nvme_stop_queues(&dev->ctrl);
csts = readl(dev->bar + NVME_REG_CSTS);
}
if (csts & NVME_CSTS_CFS || !(csts & NVME_CSTS_RDY)) {
@ -2026,7 +2026,7 @@ 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->ctrl);
nvme_start_queues(&dev->ctrl);
nvme_dev_add(dev);
}