iris: reduce redundant tile cache flushes
We are flushing tile cache more often than is necessary. In
unified cache mode, tile cache flushing is expensive, evicting all
depth/pixel data from the L3$. This is only need for a handful of
cases, such as: making cpu or gpu changes globally visible
(e.g. map), fast color clears, or slow depth clears. Tile cache
flushing is a gen12+ feature.
Remove blanket flushing of tile cache on all depth/RT flushes.
Replace with selective tile cache flushing.
Improves performance in several workloads:
AztecRuins.ogl-high-offscreen-1440p 1%
UnigineValley.ogl-g2 1%
Dota 2 (replay Jul 2020).ogl-g2 1%
Counter-Strike GO.ogl-g2 1%
Manhattan.ogl-Off-19x10 2%
CarChase.ogl-Off-19x10 1%
Bioshock Infinite.ogl-g2 1%
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/10217>