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blk-mq: pass hctx to blk_mq_dispatch_rq_list

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All requests in the 'list' of blk_mq_dispatch_rq_list belong to same
hctx, so it is better to pass hctx instead of request queue, because
blk-mq's dispatch target is hctx instead of request queue.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Tested-by: Baolin Wang <baolin.wang7@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Cc: Sagi Grimberg <sagi@grimberg.me>
Cc: Baolin Wang <baolin.wang7@gmail.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Ming Lei
2020-06-30 18:24:57 +08:00
committed by Jens Axboe
parent 65c7636943
commit 445874e89f
3 changed files with 10 additions and 12 deletions
Download Patch File Download Diff File Expand all files Collapse all files

14
block/blk-mq-sched.c
View File

@ -96,10 +96,9 @@ static int blk_mq_do_dispatch_sched(struct blk_mq_hw_ctx *hctx)
struct elevator_queue *e = q->elevator; struct elevator_queue *e = q->elevator;
LIST_HEAD(rq_list); LIST_HEAD(rq_list);
int ret = 0; int ret = 0;
struct request *rq;
do { do {
struct request *rq;
if (e->type->ops.has_work && !e->type->ops.has_work(hctx)) if (e->type->ops.has_work && !e->type->ops.has_work(hctx))
break; break;
@ -131,7 +130,7 @@ static int blk_mq_do_dispatch_sched(struct blk_mq_hw_ctx *hctx)
* in blk_mq_dispatch_rq_list(). * in blk_mq_dispatch_rq_list().
*/ */
list_add(&rq->queuelist, &rq_list); list_add(&rq->queuelist, &rq_list);
} while (blk_mq_dispatch_rq_list(q, &rq_list, true)); } while (blk_mq_dispatch_rq_list(rq->mq_hctx, &rq_list, true));
return ret; return ret;
} }
@ -161,10 +160,9 @@ static int blk_mq_do_dispatch_ctx(struct blk_mq_hw_ctx *hctx)
LIST_HEAD(rq_list); LIST_HEAD(rq_list);
struct blk_mq_ctx *ctx = READ_ONCE(hctx->dispatch_from); struct blk_mq_ctx *ctx = READ_ONCE(hctx->dispatch_from);
int ret = 0; int ret = 0;
struct request *rq;
do { do {
struct request *rq;
if (!list_empty_careful(&hctx->dispatch)) { if (!list_empty_careful(&hctx->dispatch)) {
ret = -EAGAIN; ret = -EAGAIN;
break; break;
@ -200,7 +198,7 @@ static int blk_mq_do_dispatch_ctx(struct blk_mq_hw_ctx *hctx)
/* round robin for fair dispatch */ /* round robin for fair dispatch */
ctx = blk_mq_next_ctx(hctx, rq->mq_ctx); ctx = blk_mq_next_ctx(hctx, rq->mq_ctx);
} while (blk_mq_dispatch_rq_list(q, &rq_list, true)); } while (blk_mq_dispatch_rq_list(rq->mq_hctx, &rq_list, true));
WRITE_ONCE(hctx->dispatch_from, ctx); WRITE_ONCE(hctx->dispatch_from, ctx);
return ret; return ret;
@ -240,7 +238,7 @@ static int __blk_mq_sched_dispatch_requests(struct blk_mq_hw_ctx *hctx)
*/ */
if (!list_empty(&rq_list)) { if (!list_empty(&rq_list)) {
blk_mq_sched_mark_restart_hctx(hctx); blk_mq_sched_mark_restart_hctx(hctx);
if (blk_mq_dispatch_rq_list(q, &rq_list, false)) { if (blk_mq_dispatch_rq_list(hctx, &rq_list, false)) {
if (has_sched_dispatch) if (has_sched_dispatch)
ret = blk_mq_do_dispatch_sched(hctx); ret = blk_mq_do_dispatch_sched(hctx);
else else
@ -253,7 +251,7 @@ static int __blk_mq_sched_dispatch_requests(struct blk_mq_hw_ctx *hctx)
ret = blk_mq_do_dispatch_ctx(hctx); ret = blk_mq_do_dispatch_ctx(hctx);
} else { } else {
blk_mq_flush_busy_ctxs(hctx, &rq_list); blk_mq_flush_busy_ctxs(hctx, &rq_list);
blk_mq_dispatch_rq_list(q, &rq_list, false); blk_mq_dispatch_rq_list(hctx, &rq_list, false);
} }
return ret; return ret;

6
block/blk-mq.c
View File

@ -1258,10 +1258,10 @@ static void blk_mq_handle_zone_resource(struct request *rq,
/* /*
* Returns true if we did some work AND can potentially do more. * Returns true if we did some work AND can potentially do more.
*/ */
bool blk_mq_dispatch_rq_list(struct request_queue *q, struct list_head *list, bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *hctx, struct list_head *list,
bool got_budget) bool got_budget)
{ {
struct blk_mq_hw_ctx *hctx; struct request_queue *q = hctx->queue;
struct request *rq, *nxt; struct request *rq, *nxt;
bool no_tag = false; bool no_tag = false;
int errors, queued; int errors, queued;
@ -1283,7 +1283,7 @@ bool blk_mq_dispatch_rq_list(struct request_queue *q, struct list_head *list,
rq = list_first_entry(list, struct request, queuelist); rq = list_first_entry(list, struct request, queuelist);
hctx = rq->mq_hctx; WARN_ON_ONCE(hctx != rq->mq_hctx);
if (!got_budget && !blk_mq_get_dispatch_budget(q)) { if (!got_budget && !blk_mq_get_dispatch_budget(q)) {
blk_mq_put_driver_tag(rq); blk_mq_put_driver_tag(rq);
no_budget_avail = true; no_budget_avail = true;

2
block/blk-mq.h
View File

@ -40,7 +40,7 @@ struct blk_mq_ctx {
void blk_mq_exit_queue(struct request_queue *q); void blk_mq_exit_queue(struct request_queue *q);
int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr); int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr);
void blk_mq_wake_waiters(struct request_queue *q); void blk_mq_wake_waiters(struct request_queue *q);
bool blk_mq_dispatch_rq_list(struct request_queue *, struct list_head *, bool); bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *hctx, struct list_head *, bool);
void blk_mq_add_to_requeue_list(struct request *rq, bool at_head, void blk_mq_add_to_requeue_list(struct request *rq, bool at_head,
bool kick_requeue_list); bool kick_requeue_list);
void blk_mq_flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list); void blk_mq_flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list);