Re: [PATCH] blk-throttle: fix zero wait time for iops throttled group
From: Jens Axboe
Date: Wed Jul 10 2019 - 10:00:45 EST
On 7/8/19 9:29 AM, Konstantin Khlebnikov wrote:
> After commit 991f61fe7e1d ("Blk-throttle: reduce tail io latency when iops
> limit is enforced") wait time could be zero even if group is throttled and
> cannot issue requests right now. As a result throtl_select_dispatch() turns
> into busy-loop under irq-safe queue spinlock.
>
> Fix is simple: always round up target time to the next throttle slice.
Applied, thanks. In the future, please break lines at 72 chars in
commit messages, I fixed it up.
--
Jens Axboe