On Tue, Aug 23, 2022 at 09:38:10AM +0800, Yu Kuai wrote:
> From: Yu Kuai <yukuai3@xxxxxxxxxx>
>
> Now that throtl_dequeue_tg() is called when the last bio is dispatched,
> there is no need to check the flag THROTL_TG_PENDING, since it's ensured
> to be set when bio is throttled.
>
> There are no functional changes.
>
> Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx>
> ---
> block/blk-throttle.c | 11 ++++-------
> 1 file changed, 4 insertions(+), 7 deletions(-)
>
> diff --git a/block/blk-throttle.c b/block/blk-throttle.c
> index 47142a1dd102..e47506a8ef47 100644
> --- a/block/blk-throttle.c
> +++ b/block/blk-throttle.c
> @@ -570,14 +570,11 @@ static void throtl_enqueue_tg(struct throtl_grp *tg)
>
> static void throtl_dequeue_tg(struct throtl_grp *tg)
> {
> - if (tg->flags & THROTL_TG_PENDING) {
> - struct throtl_service_queue *parent_sq =
> - tg->service_queue.parent_sq;
> + struct throtl_service_queue *parent_sq = tg->service_queue.parent_sq;
>
> - throtl_rb_erase(&tg->rb_node, parent_sq);
> - --parent_sq->nr_pending;
> - tg->flags &= ~THROTL_TG_PENDING;
> - }
> + throtl_rb_erase(&tg->rb_node, parent_sq);
> + --parent_sq->nr_pending;
> + tg->flags &= ~THROTL_TG_PENDING;
Yeah, I don't know about this one. This breaks the symmetry with
throtl_enqueue_tg() and it's a bit odd that we aren't at least
WARN_ON_ONCE() on the flag given what the flag tracks. If you want to do
this, I think the prev approach of just removing the flag is better as that
was symmetric at least.
Thanks.
--
tejun
