blk-mq: bitmap tag: fix races in bt_get() function
This update fixes few issues in bt_get() function:
- list_empty(&wait.task_list) check is not protected;
- was_empty check is always true which results in *every* thread
entering the loop resets bt_wait_state::wait_cnt counter rather
than every bt->wake_cnt'th thread;
- 'bt_wait_state::wait_cnt' counter update is redundant, since
it also gets reset in bt_clear_tag() function;
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Ming Lei <tom.leiming@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
1 file changed