NVMe: Fix nvmeq waitqueue entry initialization

We need to update the nvme queue's wait_queue_t entry during each
initialization since the nvme_thread may be ended and restarted when
the device is reset. If a device reset occurs during a large amount
of buffered IO, it would take a lot longer to complete the outstanding
requests due to the 1 second polling instead of waking up as completions
occur.

Fixes: b9afca3efb18a9b8392cb544a3e29e8b1168400c

Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

diff --git a/drivers/block/nvme-core.c b/drivers/block/nvme-core.c
index 3153692..16a886c 100644 (file)
--- a/drivers/block/nvme-core.c
+++ b/drivers/block/nvme-core.c
@@ -1333,7 +1333,6 @@ static struct nvme_queue *nvme_alloc_queue(struct nvme_dev *dev, int qid,
        nvmeq->cq_head = 0;
        nvmeq->cq_phase = 1;
        init_waitqueue_head(&nvmeq->sq_full);
-       init_waitqueue_entry(&nvmeq->sq_cong_wait, nvme_thread);
        bio_list_init(&nvmeq->sq_cong);
        INIT_LIST_HEAD(&nvmeq->iod_bio);
        nvmeq->q_db = &dev->dbs[qid * 2 * dev->db_stride];
@@ -1373,6 +1372,8 @@ static void nvme_init_queue(struct nvme_queue *nvmeq, u16 qid)
        struct nvme_dev *dev = nvmeq->dev;
        unsigned extra = nvme_queue_extra(nvmeq->q_depth);
 
+       spin_lock_irq(&nvmeq->q_lock);
+       init_waitqueue_entry(&nvmeq->sq_cong_wait, nvme_thread);
        nvmeq->sq_tail = 0;
        nvmeq->cq_head = 0;
        nvmeq->cq_phase = 1;
@@ -1382,6 +1383,7 @@ static void nvme_init_queue(struct nvme_queue *nvmeq, u16 qid)
        nvme_cancel_ios(nvmeq, false);
        nvmeq->q_suspended = 0;
        dev->online_queues++;
+       spin_unlock_irq(&nvmeq->q_lock);
 }
 
 static int nvme_create_queue(struct nvme_queue *nvmeq, int qid)
@@ -1401,10 +1403,7 @@ static int nvme_create_queue(struct nvme_queue *nvmeq, int qid)
        if (result < 0)
                goto release_sq;
 
-       spin_lock_irq(&nvmeq->q_lock);
        nvme_init_queue(nvmeq, qid);
-       spin_unlock_irq(&nvmeq->q_lock);
-
        return result;
 
  release_sq:
@@ -1543,9 +1542,6 @@ static int nvme_configure_admin_queue(struct nvme_dev *dev)
        if (result)
                return result;
 
-       spin_lock_irq(&nvmeq->q_lock);
-       nvme_init_queue(nvmeq, 0);
-       spin_unlock_irq(&nvmeq->q_lock);
        return result;
 }
 
@@ -2762,6 +2758,7 @@ static int nvme_dev_start(struct nvme_dev *dev)
                result = nvme_thread ? PTR_ERR(nvme_thread) : -EINTR;
                goto disable;
        }
+       nvme_init_queue(raw_nvmeq(dev, 0), 0);
 
        result = nvme_setup_io_queues(dev);
        if (result)