[PATCH 1/4] blk-mq-tag: support queue filter in bt_tags_iter()

chengming.zhou
2023-08-21T07:41:44Z

From: Chengming Zhou <zhouchengming@bytedance.com>

The only user of bt_for_each() is blk_mq_queue_tag_busy_iter(), which
need to filter queue when iterate the tags. In preparation of removing
bt_for_each(), support queue filter in bt_tags_iter().

The new created __blk_mq_tagset_busy_iter() will be used by the next
patch to iterate requests of only one specified queue.

Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
---
block/blk-mq-tag.c | 45 ++++++++++++++++++++++++++++++---------------
1 file changed, 30 insertions(+), 15 deletions(-)

diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c
index cc57e2dd9a0b..75b33ae6acef 100644
--- a/block/blk-mq-tag.c
+++ b/block/blk-mq-tag.c
@@ -329,6 +329,7 @@ struct bt_tags_iter_data {
busy_tag_iter_fn *fn;
void *data;
unsigned int flags;
+ struct request_queue *q;
};

#define BT_TAG_ITER_RESERVED (1 << 0)
@@ -357,9 +358,13 @@ static bool bt_tags_iter(struct sbitmap *bitmap, unsigned int bitnr, void *data)
if (!rq)
return true;

+ if (iter_data->q && iter_data->q != rq->q)
+ goto out;
+
if (!(iter_data->flags & BT_TAG_ITER_STARTED) ||
blk_mq_request_started(rq))
ret = iter_data->fn(rq, iter_data->data);
+out:
if (!iter_static_rqs)
blk_mq_put_rq_ref(rq);
return ret;
@@ -378,13 +383,15 @@ static bool bt_tags_iter(struct sbitmap *bitmap, unsigned int bitnr, void *data)
* @flags: BT_TAG_ITER_*
*/
static void bt_tags_for_each(struct blk_mq_tags *tags, struct sbitmap_queue *bt,
- busy_tag_iter_fn *fn, void *data, unsigned int flags)
+ busy_tag_iter_fn *fn, void *data, unsigned int flags,
+ struct request_queue *q)
{
struct bt_tags_iter_data iter_data = {
.tags = tags,
.fn = fn,
.data = data,
.flags = flags,
+ .q = q,
};

if (tags->rqs)
@@ -392,14 +399,15 @@ static void bt_tags_for_each(struct blk_mq_tags *tags, struct sbitmap_queue *bt,
}

static void __blk_mq_all_tag_iter(struct blk_mq_tags *tags,
- busy_tag_iter_fn *fn, void *priv, unsigned int flags)
+ busy_tag_iter_fn *fn, void *priv, unsigned int flags,
+ struct request_queue *q)
{
WARN_ON_ONCE(flags & BT_TAG_ITER_RESERVED);

if (tags->nr_reserved_tags)
bt_tags_for_each(tags, &tags->breserved_tags, fn, priv,
- flags | BT_TAG_ITER_RESERVED);
- bt_tags_for_each(tags, &tags->bitmap_tags, fn, priv, flags);
+ flags | BT_TAG_ITER_RESERVED, q);
+ bt_tags_for_each(tags, &tags->bitmap_tags, fn, priv, flags, q);
}

/**
@@ -417,7 +425,23 @@ static void __blk_mq_all_tag_iter(struct blk_mq_tags *tags,
void blk_mq_all_tag_iter(struct blk_mq_tags *tags, busy_tag_iter_fn *fn,
void *priv)
{
- __blk_mq_all_tag_iter(tags, fn, priv, BT_TAG_ITER_STATIC_RQS);
+ __blk_mq_all_tag_iter(tags, fn, priv, BT_TAG_ITER_STATIC_RQS, NULL);
+}
+
+static void __blk_mq_tagset_busy_iter(struct blk_mq_tag_set *tagset,
+ busy_tag_iter_fn *fn, void *priv,
+ struct request_queue *q)
+{
+ unsigned int flags = tagset->flags;
+ int i, nr_tags;
+
+ nr_tags = blk_mq_is_shared_tags(flags) ? 1 : tagset->nr_hw_queues;
+
+ for (i = 0; i < nr_tags; i++) {
+ if (tagset->tags && tagset->tags[i])
+ __blk_mq_all_tag_iter(tagset->tags[i], fn, priv,
+ BT_TAG_ITER_STARTED, q);
+ }
}

/**
@@ -436,16 +460,7 @@ void blk_mq_all_tag_iter(struct blk_mq_tags *tags, busy_tag_iter_fn *fn,
void blk_mq_tagset_busy_iter(struct blk_mq_tag_set *tagset,
busy_tag_iter_fn *fn, void *priv)
{
- unsigned int flags = tagset->flags;
- int i, nr_tags;
-
- nr_tags = blk_mq_is_shared_tags(flags) ? 1 : tagset->nr_hw_queues;
-
- for (i = 0; i < nr_tags; i++) {
- if (tagset->tags && tagset->tags[i])
- __blk_mq_all_tag_iter(tagset->tags[i], fn, priv,
- BT_TAG_ITER_STARTED);
- }
+ __blk_mq_tagset_busy_iter(tagset, fn, priv, NULL);
}
EXPORT_SYMBOL(blk_mq_tagset_busy_iter);

--
2.41.0