Make it easier to understand the purpose of the functions that iterate
over requests by documenting their purpose. Fix three minor spelling
mistakes in comments in these functions.
Signed-off-by: Bart Van Assche <bvanassche@xxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Ming Lei <ming.lei@xxxxxxxxxx>
Cc: Jianchao Wang <jianchao.w.wang@xxxxxxxxxx>
Cc: Hannes Reinecke <hare@xxxxxxxx>
Cc: Johannes Thumshirn <jthumshirn@xxxxxxx>
---
block/blk-mq-tag.c | 30 +++++++++++++++++++++++++++---
1 file changed, 27 insertions(+), 3 deletions(-)
diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c
index 94e1ed667b6e..cb5db0c3cc32 100644
--- a/block/blk-mq-tag.c
+++ b/block/blk-mq-tag.c
@@ -232,13 +232,19 @@ static bool bt_iter(struct sbitmap *bitmap, unsigned int bitnr, void *data)
/*
* We can hit rq == NULL here, because the tagging functions
- * test and set the bit before assining ->rqs[].
+ * test and set the bit before assigning ->rqs[].
*/
if (rq && rq->q == hctx->queue)
iter_data->fn(hctx, rq, iter_data->data, reserved);
return true;
}
+/*
+ * Call function @fn(@hctx, rq, @data, @reserved) for each request queued on
+ * @hctx that has been assigned a driver tag. @reserved indicates whether @bt
+ * is the breserved_tags member or the bitmap_tags member of struct
+ * blk_mq_tags.
+ */
static void bt_for_each(struct blk_mq_hw_ctx *hctx, struct sbitmap_queue *bt,
busy_iter_fn *fn, void *data, bool reserved)
{
@@ -280,6 +286,11 @@ static bool bt_tags_iter(struct sbitmap *bitmap, unsigned int bitnr, void *data)
return true;
}
+/*
+ * Call function @fn(rq, @data, @reserved) for each request in @tags that has
+ * been started. @reserved indicates whether @bt is the breserved_tags member
+ * or the bitmap_tags member of struct blk_mq_tags.
+ */
static void bt_tags_for_each(struct blk_mq_tags *tags, struct sbitmap_queue *bt,
busy_tag_iter_fn *fn, void *data, bool reserved)
{
@@ -294,6 +305,10 @@ static void bt_tags_for_each(struct blk_mq_tags *tags, struct sbitmap_queue *bt,
sbitmap_for_each_set(&bt->sb, bt_tags_iter, &iter_data);
}
+/*
+ * Call @fn(rq, @priv, reserved) for each started request in @tags. 'reserved'
+ * indicates whether or not 'rq' is a reserved request.
+ */
static void blk_mq_all_tag_busy_iter(struct blk_mq_tags *tags,
busy_tag_iter_fn *fn, void *priv)
{
@@ -302,6 +317,10 @@ static void blk_mq_all_tag_busy_iter(struct blk_mq_tags *tags,
bt_tags_for_each(tags, &tags->bitmap_tags, fn, priv, false);
}
+/*
+ * Call @fn(rq, @priv, reserved) for each request in @tagset. 'reserved'
+ * indicates whether or not 'rq' is a reserved request.
+ */
void blk_mq_tagset_busy_iter(struct blk_mq_tag_set *tagset,
busy_tag_iter_fn *fn, void *priv)
{
@@ -314,6 +333,11 @@ void blk_mq_tagset_busy_iter(struct blk_mq_tag_set *tagset,
}
EXPORT_SYMBOL(blk_mq_tagset_busy_iter);
+/*
+ * Call @fn(rq, @priv, reserved) for each request associated with request
+ * queue @q or any queue it shares tags with and that has been assigned a
+ * driver tag. 'reserved' indicates whether or not 'rq' is a reserved request.
+ */
void blk_mq_queue_tag_busy_iter(struct request_queue *q, busy_iter_fn *fn,
void *priv)
{
@@ -323,7 +347,7 @@ void blk_mq_queue_tag_busy_iter(struct request_queue *q, busy_iter_fn *fn,
/*
* __blk_mq_update_nr_hw_queues will update the nr_hw_queues and
* queue_hw_ctx after freeze the queue. So we could use q_usage_counter
- * to avoid race with it. __blk_mq_update_nr_hw_queues will users
+ * to avoid race with it. __blk_mq_update_nr_hw_queues will use
* synchronize_rcu to ensure all of the users go out of the critical
* section below and see zeroed q_usage_counter.
*/
@@ -337,7 +361,7 @@ void blk_mq_queue_tag_busy_iter(struct request_queue *q, busy_iter_fn *fn,
struct blk_mq_tags *tags = hctx->tags;
/*
- * If not software queues are currently mapped to this
+ * If no software queues are currently mapped to this
* hardware queue, there's nothing to check
*/
if (!blk_mq_hw_queue_mapped(hctx))
--
2.19.0.397.gdd90340f6a-goog
