We convert 'nr_active' from atomic_t to newly provied refcount_t type and API, which can prevent accidental counter overflows and underflows.
Signed-off-by: Yufen Yu <[email protected]> --- block/blk-mq-debugfs.c | 2 +- block/blk-mq-tag.c | 2 +- block/blk-mq.c | 8 ++++---- block/blk-mq.h | 2 +- include/linux/blk-mq.h | 2 +- 5 files changed, 8 insertions(+), 8 deletions(-) diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c index ec1d18cb643c..81536b7201be 100644 --- a/block/blk-mq-debugfs.c +++ b/block/blk-mq-debugfs.c @@ -637,7 +637,7 @@ static int hctx_active_show(void *data, struct seq_file *m) { struct blk_mq_hw_ctx *hctx = data; - seq_printf(m, "%d\n", atomic_read(&hctx->nr_active)); + seq_printf(m, "%d\n", refcount_read(&hctx->nr_active)); return 0; } diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c index a4931fc7be8a..3fcb15fa6398 100644 --- a/block/blk-mq-tag.c +++ b/block/blk-mq-tag.c @@ -90,7 +90,7 @@ static inline bool hctx_may_queue(struct blk_mq_hw_ctx *hctx, * Allow at least some tags */ depth = max((bt->sb.depth + users - 1) / users, 4U); - return atomic_read(&hctx->nr_active) < depth; + return refcount_read(&hctx->nr_active) < depth; } static int __blk_mq_get_tag(struct blk_mq_alloc_data *data, diff --git a/block/blk-mq.c b/block/blk-mq.c index ea01c23b58a3..004773378209 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -300,7 +300,7 @@ static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data, } else { if (data->hctx->flags & BLK_MQ_F_TAG_SHARED) { rq_flags = RQF_MQ_INFLIGHT; - atomic_inc(&data->hctx->nr_active); + refcount_inc(&data->hctx->nr_active); } rq->tag = tag; rq->internal_tag = -1; @@ -514,7 +514,7 @@ void blk_mq_free_request(struct request *rq) ctx->rq_completed[rq_is_sync(rq)]++; if (rq->rq_flags & RQF_MQ_INFLIGHT) - atomic_dec(&hctx->nr_active); + refcount_dec(&hctx->nr_active); if (unlikely(laptop_mode && !blk_rq_is_passthrough(rq))) laptop_io_completion(q->backing_dev_info); @@ -1055,7 +1055,7 @@ bool blk_mq_get_driver_tag(struct request *rq) if (rq->tag >= 0) { if (shared) { rq->rq_flags |= RQF_MQ_INFLIGHT; - atomic_inc(&data.hctx->nr_active); + refcount_inc(&data.hctx->nr_active); } data.hctx->tags->rqs[rq->tag] = rq; } @@ -2710,7 +2710,7 @@ static struct blk_mq_hw_ctx *blk_mq_alloc_and_init_hctx( return NULL; } - atomic_set(&hctx->nr_active, 0); + refcount_set(&hctx->nr_active, 0); hctx->numa_node = node; hctx->queue_num = hctx_idx; diff --git a/block/blk-mq.h b/block/blk-mq.h index 60698b4c25a2..26089d7679a2 100644 --- a/block/blk-mq.h +++ b/block/blk-mq.h @@ -218,7 +218,7 @@ static inline void __blk_mq_put_driver_tag(struct blk_mq_hw_ctx *hctx, if (rq->rq_flags & RQF_MQ_INFLIGHT) { rq->rq_flags &= ~RQF_MQ_INFLIGHT; - atomic_dec(&hctx->nr_active); + refcount_dec(&hctx->nr_active); } } diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index b0c814bcc7e3..8868e56d7532 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -56,7 +56,7 @@ struct blk_mq_hw_ctx { unsigned int numa_node; unsigned int queue_num; - atomic_t nr_active; + refcount_t nr_active; unsigned int nr_expired; struct hlist_node cpuhp_dead; -- 2.16.2.dirty
