blk_co_preadv and blk_co_pwritev calls bdrv_inc_in_flight and bdrv_dec_in_flight. But they calls correspondingly bdrv_co_preadv and bdrv_co_pwritev, which inc/dec in-flight count by themselves. Counting in-flight requests in blk_ layer is redundant, drop it.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com> --- Hi all! Is it a bug or a feature? Why do we call inc/dec twice for read/write? We don't do this for flush and discard.. (patch is called RFC, but it may be applied as is, if it is OK) block/block-backend.c | 11 ++--------- 1 file changed, 2 insertions(+), 9 deletions(-) diff --git a/block/block-backend.c b/block/block-backend.c index baef8e7abc..8219f59d93 100644 --- a/block/block-backend.c +++ b/block/block-backend.c @@ -1094,17 +1094,13 @@ int coroutine_fn blk_co_preadv(BlockBackend *blk, int64_t offset, return ret; } - bdrv_inc_in_flight(bs); - /* throttling disk I/O */ if (blk->public.throttle_group_member.throttle_state) { throttle_group_co_io_limits_intercept(&blk->public.throttle_group_member, bytes, false); } - ret = bdrv_co_preadv(blk->root, offset, bytes, qiov, flags); - bdrv_dec_in_flight(bs); - return ret; + return bdrv_co_preadv(blk->root, offset, bytes, qiov, flags); } int coroutine_fn blk_co_pwritev(BlockBackend *blk, int64_t offset, @@ -1121,7 +1117,6 @@ int coroutine_fn blk_co_pwritev(BlockBackend *blk, int64_t offset, return ret; } - bdrv_inc_in_flight(bs); /* throttling disk I/O */ if (blk->public.throttle_group_member.throttle_state) { throttle_group_co_io_limits_intercept(&blk->public.throttle_group_member, @@ -1132,9 +1127,7 @@ int coroutine_fn blk_co_pwritev(BlockBackend *blk, int64_t offset, flags |= BDRV_REQ_FUA; } - ret = bdrv_co_pwritev(blk->root, offset, bytes, qiov, flags); - bdrv_dec_in_flight(bs); - return ret; + return bdrv_co_pwritev(blk->root, offset, bytes, qiov, flags); } typedef struct BlkRwCo { -- 2.11.1