[PATCH v2 3/4] block/mq-deadline: Introduce deadline_first_rq_past_pos()

Bart Van Assche
2023-12-18T21:14:17Z

Prepare for introducing a second caller.

Cc: Damien Le Moal <dlemoal@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
---
block/mq-deadline.c | 35 ++++++++++++++++++++++++-----------
1 file changed, 24 insertions(+), 11 deletions(-)

diff --git a/block/mq-deadline.c b/block/mq-deadline.c
index a5341a37c840..c0f92cc729ca 100644
--- a/block/mq-deadline.c
+++ b/block/mq-deadline.c
@@ -147,6 +147,28 @@ deadline_latter_request(struct request *rq)
return NULL;
}

+/*
+ * Return the first request with the given priority, data direction and for
+ * which blk_rq_pos() >= @pos.
+ */
+static struct request *deadline_first_rq_past_pos(struct dd_per_prio *per_prio,
+ enum dd_data_dir data_dir, sector_t pos)
+{
+ struct rb_node *node = per_prio->sort_list[data_dir].rb_node;
+ struct request *rq, *res = NULL;
+
+ while (node) {
+ rq = rb_entry_rq(node);
+ if (blk_rq_pos(rq) >= pos) {
+ res = rq;
+ node = node->rb_left;
+ } else {
+ node = node->rb_right;
+ }
+ }
+ return res;
+}
+
/*
* Return the first request for which blk_rq_pos() >= @pos. For zoned devices,
* return the first request after the start of the zone containing @pos.
@@ -155,7 +177,7 @@ static inline struct request *deadline_from_pos(struct dd_per_prio *per_prio,
enum dd_data_dir data_dir, sector_t pos)
{
struct rb_node *node = per_prio->sort_list[data_dir].rb_node;
- struct request *rq, *res = NULL;
+ struct request *rq;

if (!node)
return NULL;
@@ -169,16 +191,7 @@ static inline struct request *deadline_from_pos(struct dd_per_prio *per_prio,
if (blk_rq_is_seq_zoned_write(rq))
pos = round_down(pos, rq->q->limits.chunk_sectors);

- while (node) {
- rq = rb_entry_rq(node);
- if (blk_rq_pos(rq) >= pos) {
- res = rq;
- node = node->rb_left;
- } else {
- node = node->rb_right;
- }
- }
- return res;
+ return deadline_first_rq_past_pos(per_prio, data_dir, pos);
}

/*