diff options
| -rw-r--r-- | block/blk-flush.c | 4 | ||||
| -rw-r--r-- | block/blk-mq-tag.c | 2 | ||||
| -rw-r--r-- | block/blk-mq.c | 12 | ||||
| -rw-r--r-- | block/blk.h | 31 | ||||
| -rw-r--r-- | include/linux/blk-mq.h | 2 |
5 files changed, 41 insertions, 10 deletions
diff --git a/block/blk-flush.c b/block/blk-flush.c index f78bb39e589e..e4df894189ce 100644 --- a/block/blk-flush.c +++ b/block/blk-flush.c @@ -229,7 +229,7 @@ static void flush_end_io(struct request *flush_rq, blk_status_t error) /* release the tag's ownership to the req cloned from */ spin_lock_irqsave(&fq->mq_flush_lock, flags); - if (!refcount_dec_and_test(&flush_rq->ref)) { + if (!req_ref_put_and_test(flush_rq)) { fq->rq_status = error; spin_unlock_irqrestore(&fq->mq_flush_lock, flags); return; @@ -349,7 +349,7 @@ static void blk_kick_flush(struct request_queue *q, struct blk_flush_queue *fq, * and READ flush_rq->end_io */ smp_wmb(); - refcount_set(&flush_rq->ref, 1); + req_ref_set(flush_rq, 1); blk_flush_queue_rq(flush_rq, false); } diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c index 995336abee33..380e2dd31bfc 100644 --- a/block/blk-mq-tag.c +++ b/block/blk-mq-tag.c @@ -228,7 +228,7 @@ static struct request *blk_mq_find_and_get_req(struct blk_mq_tags *tags, spin_lock_irqsave(&tags->lock, flags); rq = tags->rqs[bitnr]; - if (!rq || rq->tag != bitnr || !refcount_inc_not_zero(&rq->ref)) + if (!rq || rq->tag != bitnr || !req_ref_inc_not_zero(rq)) rq = NULL; spin_unlock_irqrestore(&tags->lock, flags); return rq; diff --git a/block/blk-mq.c b/block/blk-mq.c index fc4520e992b1..8c7cab75229e 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -394,7 +394,7 @@ static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data, INIT_LIST_HEAD(&rq->queuelist); /* tag was already set */ WRITE_ONCE(rq->deadline, 0); - refcount_set(&rq->ref, 1); + req_ref_set(rq, 1); if (rq->rq_flags & RQF_ELV) { struct elevator_queue *e = data->q->elevator; @@ -642,7 +642,7 @@ void blk_mq_free_request(struct request *rq) rq_qos_done(q, rq); WRITE_ONCE(rq->state, MQ_RQ_IDLE); - if (refcount_dec_and_test(&rq->ref)) + if (req_ref_put_and_test(rq)) __blk_mq_free_request(rq); } EXPORT_SYMBOL_GPL(blk_mq_free_request); @@ -938,7 +938,7 @@ void blk_mq_end_request_batch(struct io_comp_batch *iob) rq_qos_done(rq->q, rq); WRITE_ONCE(rq->state, MQ_RQ_IDLE); - if (!refcount_dec_and_test(&rq->ref)) + if (!req_ref_put_and_test(rq)) continue; blk_crypto_free_request(rq); @@ -1401,7 +1401,7 @@ void blk_mq_put_rq_ref(struct request *rq) { if (is_flush_rq(rq)) rq->end_io(rq, 0); - else if (refcount_dec_and_test(&rq->ref)) + else if (req_ref_put_and_test(rq)) __blk_mq_free_request(rq); } @@ -3049,7 +3049,7 @@ static void blk_mq_clear_rq_mapping(struct blk_mq_tags *drv_tags, unsigned long rq_addr = (unsigned long)rq; if (rq_addr >= start && rq_addr < end) { - WARN_ON_ONCE(refcount_read(&rq->ref) != 0); + WARN_ON_ONCE(req_ref_read(rq) != 0); cmpxchg(&drv_tags->rqs[i], rq, NULL); } } @@ -3383,7 +3383,7 @@ static void blk_mq_clear_flush_rq_mapping(struct blk_mq_tags *tags, if (!tags) return; - WARN_ON_ONCE(refcount_read(&flush_rq->ref) != 0); + WARN_ON_ONCE(req_ref_read(flush_rq) != 0); for (i = 0; i < queue_depth; i++) cmpxchg(&tags->rqs[i], flush_rq, NULL); diff --git a/block/blk.h b/block/blk.h index a55d82c3d1c2..24d8b333bb03 100644 --- a/block/blk.h +++ b/block/blk.h @@ -461,4 +461,35 @@ static inline bool should_fail_request(struct block_device *part, } #endif /* CONFIG_FAIL_MAKE_REQUEST */ +/* + * Optimized request reference counting. Ideally we'd make timeouts be more + * clever, as that's the only reason we need references at all... But until + * this happens, this is faster than using refcount_t. Also see: + * + * abc54d634334 ("io_uring: switch to atomic_t for io_kiocb reference count") + */ +#define req_ref_zero_or_close_to_overflow(req) \ + ((unsigned int) atomic_read(&(req->ref)) + 127u <= 127u) + +static inline bool req_ref_inc_not_zero(struct request *req) +{ + return atomic_inc_not_zero(&req->ref); +} + +static inline bool req_ref_put_and_test(struct request *req) +{ + WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req)); + return atomic_dec_and_test(&req->ref); +} + +static inline void req_ref_set(struct request *req, int value) +{ + atomic_set(&req->ref, value); +} + +static inline int req_ref_read(struct request *req) +{ + return atomic_read(&req->ref); +} + #endif /* BLK_INTERNAL_H */ diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index 1b87b7c8bbff..561beb5be7ec 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -139,7 +139,7 @@ struct request { unsigned short ioprio; enum mq_rq_state state; - refcount_t ref; + atomic_t ref; unsigned long deadline; |