On Fri, Jan 28, 2022 at 04:45:21PM +0800, Yu Kuai wrote:
> If the new flag is set, then the throtl_grp will stop throttling bios.
> Prepare to canceling all throttled bios if the disk is gone.
>
> Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx>
> ---
> block/blk-throttle.c | 17 +++++++++++++----
> 1 file changed, 13 insertions(+), 4 deletions(-)
>
> diff --git a/block/blk-throttle.c b/block/blk-throttle.c
> index 7c462c006b26..abc5e506c72d 100644
> --- a/block/blk-throttle.c
> +++ b/block/blk-throttle.c
> @@ -43,8 +43,12 @@
> static struct workqueue_struct *kthrotld_workqueue;
>
> enum tg_state_flags {
> - THROTL_TG_PENDING = 1 << 0, /* on parent's pending tree */
> - THROTL_TG_WAS_EMPTY = 1 << 1, /* bio_lists[] became non-empty */
> + /* on parent's pending tree */
> + THROTL_TG_PENDING = 1 << 0,
> + /* bio_lists[] became non-empty */
> + THROTL_TG_WAS_EMPTY = 1 << 1,
> + /* starts to cancel all bios, will be set if the disk is deleted */
> + THROTL_TG_CANCELING = 1 << 2,
> };
>
> #define rb_entry_tg(node) rb_entry((node), struct throtl_grp, rb_node)
> @@ -871,7 +875,8 @@ static bool tg_may_dispatch(struct throtl_grp *tg, struct bio *bio,
> bio != throtl_peek_queued(&tg->service_queue.queued[rw]));
>
> /* If tg->bps = -1, then BW is unlimited */
> - if (bps_limit == U64_MAX && iops_limit == UINT_MAX) {
> + if ((bps_limit == U64_MAX && iops_limit == UINT_MAX) ||
> + tg->flags & THROTL_TG_CANCELING) {
> if (wait)
> *wait = 0;
> return true;
> @@ -974,6 +979,9 @@ static void tg_update_disptime(struct throtl_grp *tg)
> unsigned long read_wait = -1, write_wait = -1, min_wait = -1, disptime;
> struct bio *bio;
>
> + if (tg->flags & THROTL_TG_CANCELING)
> + goto update;
> +
The above change and the following one in tg_update_disptime() isn't
needed actually.
Also I'd suggest to fold the two into one patch.
Thanks,
Ming
