From: Christoph Hellwig <hch@lst.de>
Date: Fri, 29 May 2020 15:53:09 +0200
Subject: [PATCH] blk-mq: simplify the blk_mq_get_request calling convention
Git-commit: e6e7abffe386b614a194ec32457a00c304c980f4
Patch-mainline: v5.8-rc1
References: bsc#1175995,jsc#SLE-15608
The bio argument is entirely unused, and the request_queue can be passed
through the alloc_data, given that it needs to be filled out for the
low-level tag allocation anyway. Also rename the function to
__blk_mq_alloc_request as the switch between get and alloc in the call
chains is rather confusing.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Acked-by: Hannes Reinecke <hare@suse.com>
---
block/blk-mq.c | 36 ++++++++++++++++++++++--------------
1 file changed, 22 insertions(+), 14 deletions(-)
diff --git a/block/blk-mq.c b/block/blk-mq.c
index f15722cbfac6..74ebab41f7d2 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -332,10 +332,9 @@ static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data,
return rq;
}
-static struct request *blk_mq_get_request(struct request_queue *q,
- struct bio *bio,
- struct blk_mq_alloc_data *data)
+static struct request *__blk_mq_alloc_request(struct blk_mq_alloc_data *data)
{
+ struct request_queue *q = data->q;
struct elevator_queue *e = q->elevator;
struct request *rq;
unsigned int tag;
@@ -346,7 +345,6 @@ static struct request *blk_mq_get_request(struct request_queue *q,
if (blk_queue_rq_alloc_time(q))
alloc_time_ns = ktime_get_ns();
- data->q = q;
if (likely(!data->ctx)) {
data->ctx = blk_mq_get_ctx(q);
clear_ctx_on_error = true;
@@ -398,7 +396,11 @@ static struct request *blk_mq_get_request(struct request_queue *q,
struct request *blk_mq_alloc_request(struct request_queue *q, unsigned int op,
blk_mq_req_flags_t flags)
{
- struct blk_mq_alloc_data alloc_data = { .flags = flags, .cmd_flags = op };
+ struct blk_mq_alloc_data data = {
+ .q = q,
+ .flags = flags,
+ .cmd_flags = op,
+ };
struct request *rq;
int ret;
@@ -406,7 +408,7 @@ struct request *blk_mq_alloc_request(struct request_queue *q, unsigned int op,
if (ret)
return ERR_PTR(ret);
- rq = blk_mq_get_request(q, NULL, &alloc_data);
+ rq = __blk_mq_alloc_request(&data);
if (!rq)
goto out_queue_exit;
rq->__data_len = 0;
@@ -422,7 +424,11 @@ EXPORT_SYMBOL(blk_mq_alloc_request);
struct request *blk_mq_alloc_request_hctx(struct request_queue *q,
unsigned int op, blk_mq_req_flags_t flags, unsigned int hctx_idx)
{
- struct blk_mq_alloc_data alloc_data = { .flags = flags, .cmd_flags = op };
+ struct blk_mq_alloc_data data = {
+ .q = q,
+ .flags = flags,
+ .cmd_flags = op,
+ };
struct request *rq;
unsigned int cpu;
int ret;
@@ -448,14 +454,14 @@ struct request *blk_mq_alloc_request_hctx(struct request_queue *q,
* If not tell the caller that it should skip this queue.
*/
ret = -EXDEV;
- alloc_data.hctx = q->queue_hw_ctx[hctx_idx];
- if (!blk_mq_hw_queue_mapped(alloc_data.hctx))
+ data.hctx = q->queue_hw_ctx[hctx_idx];
+ if (!blk_mq_hw_queue_mapped(data.hctx))
goto out_queue_exit;
- cpu = cpumask_first_and(alloc_data.hctx->cpumask, cpu_online_mask);
- alloc_data.ctx = __blk_mq_get_ctx(q, cpu);
+ cpu = cpumask_first_and(data.hctx->cpumask, cpu_online_mask);
+ data.ctx = __blk_mq_get_ctx(q, cpu);
ret = -EWOULDBLOCK;
- rq = blk_mq_get_request(q, NULL, &alloc_data);
+ rq = __blk_mq_alloc_request(&data);
if (!rq)
goto out_queue_exit;
return rq;
@@ -2027,7 +2033,9 @@ blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)
{
const int is_sync = op_is_sync(bio->bi_opf);
const int is_flush_fua = op_is_flush(bio->bi_opf);
- struct blk_mq_alloc_data data = { .flags = 0};
+ struct blk_mq_alloc_data data = {
+ .q = q,
+ };
struct request *rq;
struct blk_plug *plug;
struct request *same_queue_rq = NULL;
@@ -2051,7 +2059,7 @@ blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)
rq_qos_throttle(q, bio);
data.cmd_flags = bio->bi_opf;
- rq = blk_mq_get_request(q, bio, &data);
+ rq = __blk_mq_alloc_request(&data);
if (unlikely(!rq)) {
rq_qos_cleanup(q, bio);
if (bio->bi_opf & REQ_NOWAIT)
--
2.16.4