[PATCH V2 16/20] block: move actual bio merge code into __elv_merge

Ming Lei
2017-08-05T06:58:13Z

So that we can reuse __elv_merge() to merge bio
into requests from sw queue in the following patches.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
---
block/elevator.c | 19 +++++++++++++------
1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/block/elevator.c b/block/elevator.c
index 7423e9c9cb27..2fd2f777127b 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -409,8 +409,9 @@ void elv_dispatch_add_tail(struct request_queue *q, struct request *rq)
}
EXPORT_SYMBOL(elv_dispatch_add_tail);

-enum elv_merge elv_merge(struct request_queue *q, struct request **req,
- struct bio *bio)
+static inline enum elv_merge __elv_merge(struct request_queue *q,
+ struct request **req, struct bio *bio,
+ struct hlist_head *hash, struct request *last_merge)
{
struct elevator_queue *e = q->elevator;
struct request *__rq;
@@ -427,11 +428,11 @@ enum elv_merge elv_merge(struct request_queue *q, struct request **req,
/*
* First try one-hit cache.
*/
- if (q->last_merge && elv_bio_merge_ok(q->last_merge, bio)) {
- enum elv_merge ret = blk_try_merge(q->last_merge, bio);
+ if (last_merge && elv_bio_merge_ok(last_merge, bio)) {
+ enum elv_merge ret = blk_try_merge(last_merge, bio);

if (ret != ELEVATOR_NO_MERGE) {
- *req = q->last_merge;
+ *req = last_merge;
return ret;
}
}
@@ -442,7 +443,7 @@ enum elv_merge elv_merge(struct request_queue *q, struct request **req,
/*
* See if our hash lookup can find a potential backmerge.
*/
- __rq = elv_rqhash_find(q, bio->bi_iter.bi_sector);
+ __rq = rqhash_find(hash, bio->bi_iter.bi_sector);
if (__rq && elv_bio_merge_ok(__rq, bio)) {
*req = __rq;
return ELEVATOR_BACK_MERGE;
@@ -456,6 +457,12 @@ enum elv_merge elv_merge(struct request_queue *q, struct request **req,
return ELEVATOR_NO_MERGE;
}

+enum elv_merge elv_merge(struct request_queue *q, struct request **req,
+ struct bio *bio)
+{
+ return __elv_merge(q, req, bio, q->elevator->hash, q->last_merge);
+}
+
/*
* Attempt to do an insertion back merge. Only check for the case where
* we can append 'rq' to an existing request, so we can throw 'rq' away
--
2.9.4