Re: [PATCH] blk-wbt: wake up all when we scale up, not down

On 10/11/18 1:29 PM, Josef Bacik wrote:

Tetsuo brought to my attention that I screwed up the scale_up/scale_down helpers when I factored out the rq-qos code. We need to wake up all the waiters when we add slots for requests to make, not when we shrink the slots. Otherwise we'll end up things waiting forever. This was a mistake and simply puts everything back the way it was.

I'll apply this for 4.19. I haven't hit this in testing, I'm guessing the jitter when going up and down hides the issue.