https://bugs.freedesktop.org/show_bug.cgi?id=82050
--- Comment #14 from Andy Furniss adf.lists@gmail.com --- (In reply to comment #13)
Does reverting Mesa commit 150ac07b855b5c5f879bf6ce9ca421ccd1a6c938 help for Valley or pyrit with the latest kernel?
Yes, with that reverted perf is roughly back to "good" kernel for both.