diff options
| author | Bart Van Assche <bvanassche@acm.org> | 2019-07-01 08:47:29 -0700 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2019-07-02 21:03:27 -0600 |
| commit | c05f42206f4de12b6807270fc669b45472f1bdb7 (patch) | |
| tree | 82aaf5161958336f8ef635f9f7a8daaeddad7f64 /block/blk-mq.c | |
| parent | 417232880c8a646739dbf4666a231505a1917fcb (diff) | |
blk-mq: remove blk_mq_put_ctx()
No code that occurs between blk_mq_get_ctx() and blk_mq_put_ctx() depends
on preemption being disabled for its correctness. Since removing the CPU
preemption calls does not measurably affect performance, simplify the
blk-mq code by removing the blk_mq_put_ctx() function and also by not
disabling preemption in blk_mq_get_ctx().
Cc: Hannes Reinecke <hare@suse.com>
Cc: Omar Sandoval <osandov@fb.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block/blk-mq.c')
| -rw-r--r-- | block/blk-mq.c | 16 |
1 files changed, 3 insertions, 13 deletions
diff --git a/block/blk-mq.c b/block/blk-mq.c index d89383847d09..0cb1b152f320 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -355,13 +355,13 @@ static struct request *blk_mq_get_request(struct request_queue *q, struct elevator_queue *e = q->elevator; struct request *rq; unsigned int tag; - bool put_ctx_on_error = false; + bool clear_ctx_on_error = false; blk_queue_enter_live(q); data->q = q; if (likely(!data->ctx)) { data->ctx = blk_mq_get_ctx(q); - put_ctx_on_error = true; + clear_ctx_on_error = true; } if (likely(!data->hctx)) data->hctx = blk_mq_map_queue(q, data->cmd_flags, @@ -387,10 +387,8 @@ static struct request *blk_mq_get_request(struct request_queue *q, tag = blk_mq_get_tag(data); if (tag == BLK_MQ_TAG_FAIL) { - if (put_ctx_on_error) { - blk_mq_put_ctx(data->ctx); + if (clear_ctx_on_error) data->ctx = NULL; - } blk_queue_exit(q); return NULL; } @@ -427,8 +425,6 @@ struct request *blk_mq_alloc_request(struct request_queue *q, unsigned int op, if (!rq) return ERR_PTR(-EWOULDBLOCK); - blk_mq_put_ctx(alloc_data.ctx); - rq->__data_len = 0; rq->__sector = (sector_t) -1; rq->bio = rq->biotail = NULL; @@ -1977,7 +1973,6 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) plug = current->plug; if (unlikely(is_flush_fua)) { - blk_mq_put_ctx(data.ctx); blk_mq_bio_to_request(rq, bio, nr_segs); /* bypass scheduler for flush rq */ @@ -1991,7 +1986,6 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) unsigned int request_count = plug->rq_count; struct request *last = NULL; - blk_mq_put_ctx(data.ctx); blk_mq_bio_to_request(rq, bio, nr_segs); if (!request_count) @@ -2025,8 +2019,6 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) blk_add_rq_to_plug(plug, rq); trace_block_plug(q); - blk_mq_put_ctx(data.ctx); - if (same_queue_rq) { data.hctx = same_queue_rq->mq_hctx; trace_block_unplug(q, 1, true); @@ -2035,11 +2027,9 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) } } else if ((q->nr_hw_queues > 1 && is_sync) || (!q->elevator && !data.hctx->dispatch_busy)) { - blk_mq_put_ctx(data.ctx); blk_mq_bio_to_request(rq, bio, nr_segs); blk_mq_try_issue_directly(data.hctx, rq, &cookie); } else { - blk_mq_put_ctx(data.ctx); blk_mq_bio_to_request(rq, bio, nr_segs); blk_mq_sched_insert_request(rq, false, true, true); } |