Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
blk-mq-sched: add new parameter nr_requests in blk_mq_alloc_sched_tags()
This helper only support to allocate the default number of requests,
add a new parameter to support specific number of requests.
Prepare to fix potential deadlock in the case nr_requests grow.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
authored by
Yu Kuai
and committed by
Jens Axboe
6293e336
e6320040
+19
-11
+5
-9
block/blk-mq-sched.c
+5
-9
block/blk-mq-sched.c
···
454
454
}
455
455
456
456
struct elevator_tags *blk_mq_alloc_sched_tags(struct blk_mq_tag_set *set,
457
-
unsigned int nr_hw_queues)
457
+
unsigned int nr_hw_queues, unsigned int nr_requests)
458
458
{
459
459
unsigned int nr_tags;
460
460
int i;
···
470
470
nr_tags * sizeof(struct blk_mq_tags *), gfp);
471
471
if (!et)
472
472
return NULL;
473
-
/*
474
-
* Default to double of smaller one between hw queue_depth and
475
-
* 128, since we don't split into sync/async like the old code
476
-
* did. Additionally, this is a per-hw queue depth.
477
-
*/
478
-
et->nr_requests = 2 * min_t(unsigned int, set->queue_depth,
479
-
BLKDEV_DEFAULT_RQ);
473
+
474
+
et->nr_requests = nr_requests;
480
475
et->nr_hw_queues = nr_hw_queues;
481
476
482
477
if (blk_mq_is_shared_tags(set->flags)) {
···
516
521
* concurrently.
517
522
*/
518
523
if (q->elevator) {
519
-
et = blk_mq_alloc_sched_tags(set, nr_hw_queues);
524
+
et = blk_mq_alloc_sched_tags(set, nr_hw_queues,
525
+
blk_mq_default_nr_requests(set));
520
526
if (!et)
521
527
goto out_unwind;
522
528
if (xa_insert(et_table, q->id, et, gfp))
+1
-1
block/blk-mq-sched.h
+1
-1
block/blk-mq-sched.h
···
24
24
void blk_mq_sched_free_rqs(struct request_queue *q);
25
25
26
26
struct elevator_tags *blk_mq_alloc_sched_tags(struct blk_mq_tag_set *set,
27
-
unsigned int nr_hw_queues);
27
+
unsigned int nr_hw_queues, unsigned int nr_requests);
28
28
int blk_mq_alloc_sched_tags_batch(struct xarray *et_table,
29
29
struct blk_mq_tag_set *set, unsigned int nr_hw_queues);
30
30
void blk_mq_free_sched_tags(struct elevator_tags *et,
+11
block/blk-mq.h
+11
block/blk-mq.h
···
110
110
}
111
111
112
112
/*
113
+
* Default to double of smaller one between hw queue_depth and
114
+
* 128, since we don't split into sync/async like the old code
115
+
* did. Additionally, this is a per-hw queue depth.
116
+
*/
117
+
static inline unsigned int blk_mq_default_nr_requests(
118
+
struct blk_mq_tag_set *set)
119
+
{
120
+
return 2 * min_t(unsigned int, set->queue_depth, BLKDEV_DEFAULT_RQ);
121
+
}
122
+
123
+
/*
113
124
* sysfs helpers
114
125
*/
115
126
extern void blk_mq_sysfs_init(struct request_queue *q);
+2
-1
block/elevator.c
+2
-1
block/elevator.c
···
669
669
lockdep_assert_held(&set->update_nr_hwq_lock);
670
670
671
671
if (strncmp(ctx->name, "none", 4)) {
672
-
ctx->et = blk_mq_alloc_sched_tags(set, set->nr_hw_queues);
672
+
ctx->et = blk_mq_alloc_sched_tags(set, set->nr_hw_queues,
673
+
blk_mq_default_nr_requests(set));
673
674
if (!ctx->et)
674
675
return -ENOMEM;
675
676
}