Follow the pattern what we have in bio_alloc() to set the structure
members in the structure allocation function in alloc_cmd() and pass
bio to initialize newly allocated cmd->bio member.
Follow the pattern in copy_to_nullb() to use result of one function call
(null_cache_active()) to be used as a parameter to another function call
(null_insert_page()), use result of alloc_cmd() as a first parameter to
the null_handle_cmd() in null_submit_bio() function. This allow us to
remove the local variable cmd on stack in null_submit_bio() that is in
fast path.
Signed-off-by: Chaitanya Kulkarni <kch@xxxxxxxxxx>
---
drivers/block/null_blk/main.c | 12 +++++-------
1 file changed, 5 insertions(+), 7 deletions(-)
diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c
index d78fc3edb22e..e19340f686a8 100644
--- a/drivers/block/null_blk/main.c
+++ b/drivers/block/null_blk/main.c
@@ -719,7 +719,7 @@ static struct nullb_cmd *__alloc_cmd(struct nullb_queue *nq)
return NULL;
}
-static struct nullb_cmd *alloc_cmd(struct nullb_queue *nq)
+static struct nullb_cmd *alloc_cmd(struct nullb_queue *nq, struct bio *bio)
{
struct nullb_cmd *cmd;
DEFINE_WAIT(wait);
@@ -730,8 +730,10 @@ static struct nullb_cmd *alloc_cmd(struct nullb_queue *nq)
* __alloc_cmd() and a fast path call to prepare_to_wait().
*/
cmd = __alloc_cmd(nq);
- if (cmd)
+ if (cmd) {
+ cmd->bio = bio;
return cmd;
+ }
prepare_to_wait(&nq->wait, &wait, TASK_UNINTERRUPTIBLE);
io_schedule();
finish_wait(&nq->wait, &wait);
@@ -1473,12 +1475,8 @@ static void null_submit_bio(struct bio *bio)
sector_t nr_sectors = bio_sectors(bio);
struct nullb *nullb = bio->bi_bdev->bd_disk->private_data;
struct nullb_queue *nq = nullb_to_queue(nullb);
- struct nullb_cmd *cmd;
-
- cmd = alloc_cmd(nq);
- cmd->bio = bio;
- null_handle_cmd(cmd, sector, nr_sectors, bio_op(bio));
+ null_handle_cmd(alloc_cmd(nq, bio), sector, nr_sectors, bio_op(bio));
}
static bool should_timeout_request(struct request *rq)
--
2.29.0
