| Message ID | 20190322144818.987-3-yuyufen@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | blk-mq: convert atomic_t to refcount_t | expand |
On Fri, Mar 22, 2019 at 10:48:18PM +0800, Yufen Yu wrote: > We convert 'active_queues' from atomic_t to newly provied > refcount_t type and API, which can prevent accidental counter > overflows and underflows. There is no initialization using refcount_set(), which leads me to believe we're 0 initialized and then it's broken again. > Signed-off-by: Yufen Yu <yuyufen@huawei.com> > --- > block/blk-mq-debugfs.c | 2 +- > block/blk-mq-tag.c | 6 +++--- > block/blk-mq-tag.h | 2 +- > 3 files changed, 5 insertions(+), 5 deletions(-) > > diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c > index 81536b7201be..48f0cc2c90ba 100644 > --- a/block/blk-mq-debugfs.c > +++ b/block/blk-mq-debugfs.c > @@ -473,7 +473,7 @@ static void blk_mq_debugfs_tags_show(struct seq_file *m, > seq_printf(m, "nr_tags=%u\n", tags->nr_tags); > seq_printf(m, "nr_reserved_tags=%u\n", tags->nr_reserved_tags); > seq_printf(m, "active_queues=%d\n", > - atomic_read(&tags->active_queues)); > + refcount_read(&tags->active_queues)); > > seq_puts(m, "\nbitmap_tags:\n"); > sbitmap_queue_show(&tags->bitmap_tags, m); > diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c > index 3fcb15fa6398..1d713f221bf7 100644 > --- a/block/blk-mq-tag.c > +++ b/block/blk-mq-tag.c > @@ -31,7 +31,7 @@ bool __blk_mq_tag_busy(struct blk_mq_hw_ctx *hctx) > { > if (!test_bit(BLK_MQ_S_TAG_ACTIVE, &hctx->state) && > !test_and_set_bit(BLK_MQ_S_TAG_ACTIVE, &hctx->state)) > - atomic_inc(&hctx->tags->active_queues); > + refcount_inc(&hctx->tags->active_queues); > > return true; > } > @@ -57,7 +57,7 @@ void __blk_mq_tag_idle(struct blk_mq_hw_ctx *hctx) > if (!test_and_clear_bit(BLK_MQ_S_TAG_ACTIVE, &hctx->state)) > return; > > - atomic_dec(&tags->active_queues); > + refcount_dec(&tags->active_queues); > > blk_mq_tag_wakeup_all(tags, false); > } > @@ -82,7 +82,7 @@ static inline bool hctx_may_queue(struct blk_mq_hw_ctx *hctx, > if (bt->sb.depth == 1) > return true; > > - users = atomic_read(&hctx->tags->active_queues); > + users = refcount_read(&hctx->tags->active_queues); > if (!users) > return true; > > diff --git a/block/blk-mq-tag.h b/block/blk-mq-tag.h > index 61deab0b5a5a..e948b4833a2a 100644 > --- a/block/blk-mq-tag.h > +++ b/block/blk-mq-tag.h > @@ -11,7 +11,7 @@ struct blk_mq_tags { > unsigned int nr_tags; > unsigned int nr_reserved_tags; > > - atomic_t active_queues; > + refcount_t active_queues; > > struct sbitmap_queue bitmap_tags; > struct sbitmap_queue breserved_tags; > -- > 2.16.2.dirty >
diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c index 81536b7201be..48f0cc2c90ba 100644 --- a/block/blk-mq-debugfs.c +++ b/block/blk-mq-debugfs.c @@ -473,7 +473,7 @@ static void blk_mq_debugfs_tags_show(struct seq_file *m, seq_printf(m, "nr_tags=%u\n", tags->nr_tags); seq_printf(m, "nr_reserved_tags=%u\n", tags->nr_reserved_tags); seq_printf(m, "active_queues=%d\n", - atomic_read(&tags->active_queues)); + refcount_read(&tags->active_queues)); seq_puts(m, "\nbitmap_tags:\n"); sbitmap_queue_show(&tags->bitmap_tags, m); diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c index 3fcb15fa6398..1d713f221bf7 100644 --- a/block/blk-mq-tag.c +++ b/block/blk-mq-tag.c @@ -31,7 +31,7 @@ bool __blk_mq_tag_busy(struct blk_mq_hw_ctx *hctx) { if (!test_bit(BLK_MQ_S_TAG_ACTIVE, &hctx->state) && !test_and_set_bit(BLK_MQ_S_TAG_ACTIVE, &hctx->state)) - atomic_inc(&hctx->tags->active_queues); + refcount_inc(&hctx->tags->active_queues); return true; } @@ -57,7 +57,7 @@ void __blk_mq_tag_idle(struct blk_mq_hw_ctx *hctx) if (!test_and_clear_bit(BLK_MQ_S_TAG_ACTIVE, &hctx->state)) return; - atomic_dec(&tags->active_queues); + refcount_dec(&tags->active_queues); blk_mq_tag_wakeup_all(tags, false); } @@ -82,7 +82,7 @@ static inline bool hctx_may_queue(struct blk_mq_hw_ctx *hctx, if (bt->sb.depth == 1) return true; - users = atomic_read(&hctx->tags->active_queues); + users = refcount_read(&hctx->tags->active_queues); if (!users) return true; diff --git a/block/blk-mq-tag.h b/block/blk-mq-tag.h index 61deab0b5a5a..e948b4833a2a 100644 --- a/block/blk-mq-tag.h +++ b/block/blk-mq-tag.h @@ -11,7 +11,7 @@ struct blk_mq_tags { unsigned int nr_tags; unsigned int nr_reserved_tags; - atomic_t active_queues; + refcount_t active_queues; struct sbitmap_queue bitmap_tags; struct sbitmap_queue breserved_tags;
We convert 'active_queues' from atomic_t to newly provied refcount_t type and API, which can prevent accidental counter overflows and underflows. Signed-off-by: Yufen Yu <yuyufen@huawei.com> --- block/blk-mq-debugfs.c | 2 +- block/blk-mq-tag.c | 6 +++--- block/blk-mq-tag.h | 2 +- 3 files changed, 5 insertions(+), 5 deletions(-)