NVMe: Set affinity after allocating request queues

The asynchronous namespace scanning caused affinity hints to be set before
its tagset initialized, so there was no cpu mask to set the hint. This
patch moves the affinity hint setting to after namespaces are scanned.

Reported-by: 김경산 <ks0204.kim@samsung.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

drivers/block/nvme-core.c

@@ -2439,6 +2439,22 @@ static void nvme_scan_namespaces(struct nvme_dev *dev, unsigned nn)
 	list_sort(NULL, &dev->namespaces, ns_cmp);
 }
 
+static void nvme_set_irq_hints(struct nvme_dev *dev)
+{
+	struct nvme_queue *nvmeq;
+	int i;
+
+	for (i = 0; i < dev->online_queues; i++) {
+		nvmeq = dev->queues[i];
+
+		if (!nvmeq->tags || !(*nvmeq->tags))
+			continue;
+
+		irq_set_affinity_hint(dev->entry[nvmeq->cq_vector].vector,
+					blk_mq_tags_cpumask(*nvmeq->tags));
+	}
+}
+
 static void nvme_dev_scan(struct work_struct *work)
 {
 	struct nvme_dev *dev = container_of(work, struct nvme_dev, scan_work);
@@ -2450,6 +2466,7 @@ static void nvme_dev_scan(struct work_struct *work)
 		return;
 	nvme_scan_namespaces(dev, le32_to_cpup(&ctrl->nn));
 	kfree(ctrl);
+	nvme_set_irq_hints(dev);
 }
 
 /*
@@ -2953,22 +2970,6 @@ static const struct file_operations nvme_dev_fops = {
 	.compat_ioctl	= nvme_dev_ioctl,
 };
 
-static void nvme_set_irq_hints(struct nvme_dev *dev)
-{
-	struct nvme_queue *nvmeq;
-	int i;
-
-	for (i = 0; i < dev->online_queues; i++) {
-		nvmeq = dev->queues[i];
-
-		if (!nvmeq->tags || !(*nvmeq->tags))
-			continue;
-
-		irq_set_affinity_hint(dev->entry[nvmeq->cq_vector].vector,
-					blk_mq_tags_cpumask(*nvmeq->tags));
-	}
-}
-
 static int nvme_dev_start(struct nvme_dev *dev)
 {
 	int result;
@@ -3010,8 +3011,6 @@ static int nvme_dev_start(struct nvme_dev *dev)
 	if (result)
 		goto free_tags;
 
-	nvme_set_irq_hints(dev);
-
 	dev->event_limit = 1;
 	return result;
 
@@ -3062,7 +3061,6 @@ static int nvme_dev_resume(struct nvme_dev *dev)
 	} else {
 		nvme_unfreeze_queues(dev);
 		nvme_dev_add(dev);
-		nvme_set_irq_hints(dev);
 	}
 	return 0;
 }