[PATCH 5.17 632/772] bfq: Remove pointless bfq_init_rq() calls

Greg Kroah-Hartman
2022-06-07T21:37:46Z

From: Jan Kara <jack@suse.cz>

commit 5f550ede5edf846ecc0067be1ba80514e6fe7f8e upstream.

We call bfq_init_rq() from request merging functions where requests we
get should have already gone through bfq_init_rq() during insert and
anyway we want to do anything only if the request is already tracked by
BFQ. So replace calls to bfq_init_rq() with RQ_BFQQ() instead to simply
skip requests untracked by BFQ. We move bfq_init_rq() call in
bfq_insert_request() a bit earlier to cover request merging and thus
can transfer FIFO position in case of a merge.

CC: stable@vger.kernel.org
Tested-by: "yukuai (C)" <yukuai3@huawei.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220401102752.8599-6-jack@suse.cz
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
block/bfq-iosched.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

--- a/block/bfq-iosched.c
+++ b/block/bfq-iosched.c
@@ -2501,8 +2501,6 @@ static int bfq_request_merge(struct requ
return ELEVATOR_NO_MERGE;
}

-static struct bfq_queue *bfq_init_rq(struct request *rq);
-
static void bfq_request_merged(struct request_queue *q, struct request *req,
enum elv_merge type)
{
@@ -2511,7 +2509,7 @@ static void bfq_request_merged(struct re
blk_rq_pos(req) <
blk_rq_pos(container_of(rb_prev(&req->rb_node),
struct request, rb_node))) {
- struct bfq_queue *bfqq = bfq_init_rq(req);
+ struct bfq_queue *bfqq = RQ_BFQQ(req);
struct bfq_data *bfqd;
struct request *prev, *next_rq;

@@ -2563,8 +2561,8 @@ static void bfq_request_merged(struct re
static void bfq_requests_merged(struct request_queue *q, struct request *rq,
struct request *next)
{
- struct bfq_queue *bfqq = bfq_init_rq(rq),
- *next_bfqq = bfq_init_rq(next);
+ struct bfq_queue *bfqq = RQ_BFQQ(rq),
+ *next_bfqq = RQ_BFQQ(next);

if (!bfqq)
goto remove;
@@ -6133,6 +6131,8 @@ static inline void bfq_update_insert_sta
unsigned int cmd_flags) {}
#endif /* CONFIG_BFQ_CGROUP_DEBUG */

+static struct bfq_queue *bfq_init_rq(struct request *rq);
+
static void bfq_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq,
bool at_head)
{
@@ -6148,6 +6148,7 @@ static void bfq_insert_request(struct bl
bfqg_stats_update_legacy_io(q, rq);
#endif
spin_lock_irq(&bfqd->lock);
+ bfqq = bfq_init_rq(rq);
if (blk_mq_sched_try_insert_merge(q, rq, &free)) {
spin_unlock_irq(&bfqd->lock);
blk_mq_free_requests(&free);
@@ -6156,7 +6157,6 @@ static void bfq_insert_request(struct bl

trace_block_rq_insert(rq);

- bfqq = bfq_init_rq(rq);
if (!bfqq || at_head) {
if (at_head)
list_add(&rq->queuelist, &bfqd->dispatch);