[PATCH V3 1/6] blk-mq: figure out correct numa node for hw queue

[Ming Lei <ming.lei@xxxxxxxxxx>]

The current code always uses default queue map and hw queue index
for figuring out the numa node for hw queue, this way isn't correct
because blk-mq supports three queue maps, and the correct queue map
should be used for the specified hw queue.

Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx>
---
 block/blk-mq.c | 36 ++++++++++++++++++++++++++++++------
 1 file changed, 30 insertions(+), 6 deletions(-)

diff --git a/block/blk-mq.c b/block/blk-mq.c
index a05ce7725031..5d25abf9e551 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -3107,15 +3107,41 @@ void blk_mq_free_rq_map(struct blk_mq_tags *tags)
 	blk_mq_free_tags(tags);
 }
 
+static enum hctx_type hctx_idx_to_type(struct blk_mq_tag_set *set,
+		unsigned int hctx_idx)
+{
+	int i;
+
+	for (i = 0; i < set->nr_maps; i++) {
+		unsigned int start = set->map[i].queue_offset;
+		unsigned int end = start + set->map[i].nr_queues;
+
+		if (hctx_idx >= start && hctx_idx < end)
+			break;
+	}
+
+	if (i >= set->nr_maps)
+		i = HCTX_TYPE_DEFAULT;
+
+	return i;
+}
+
+static int blk_mq_get_hctx_node(struct blk_mq_tag_set *set,
+		unsigned int hctx_idx)
+{
+	enum hctx_type type = hctx_idx_to_type(set, hctx_idx);
+
+	return blk_mq_hw_queue_to_node(&set->map[type], hctx_idx);
+}
+
 static struct blk_mq_tags *blk_mq_alloc_rq_map(struct blk_mq_tag_set *set,
 					       unsigned int hctx_idx,
 					       unsigned int nr_tags,
 					       unsigned int reserved_tags)
 {
+	int node = blk_mq_get_hctx_node(set, hctx_idx);
 	struct blk_mq_tags *tags;
-	int node;
 
-	node = blk_mq_hw_queue_to_node(&set->map[HCTX_TYPE_DEFAULT], hctx_idx);
 	if (node == NUMA_NO_NODE)
 		node = set->numa_node;
 
@@ -3164,10 +3190,9 @@ static int blk_mq_alloc_rqs(struct blk_mq_tag_set *set,
 			    unsigned int hctx_idx, unsigned int depth)
 {
 	unsigned int i, j, entries_per_page, max_order = 4;
+	int node = blk_mq_get_hctx_node(set, hctx_idx);
 	size_t rq_size, left;
-	int node;
 
-	node = blk_mq_hw_queue_to_node(&set->map[HCTX_TYPE_DEFAULT], hctx_idx);
 	if (node == NUMA_NO_NODE)
 		node = set->numa_node;
 
@@ -3941,10 +3966,9 @@ static void blk_mq_realloc_hw_ctxs(struct blk_mq_tag_set *set,
 	/* protect against switching io scheduler  */
 	mutex_lock(&q->sysfs_lock);
 	for (i = 0; i < set->nr_hw_queues; i++) {
-		int node;
+		int node = blk_mq_get_hctx_node(set, i);
 		struct blk_mq_hw_ctx *hctx;
 
-		node = blk_mq_hw_queue_to_node(&set->map[HCTX_TYPE_DEFAULT], i);
 		/*
 		 * If the hw queue has been mapped to another numa node,
 		 * we need to realloc the hctx. If allocation fails, fallback
-- 
2.31.1