[Mesa-dev] [PATCH 00/31] Mesa: Moving from _NEW flags to NewDriverState

[Marek Olšák]

Hi,

This series only affects st/mesa, but other drivers can optionally
be switched to this.

I realized we don't need to flag _NEW flags for most states and we
also don't need to call _mesa_update_state in most cases.

Firstly, this series cleans up _mesa_update_state_locked. A lot of
the update functions in there are replaced with helper functions
called by drivers directly.

While doing that, the series replaces most occurences of _NEW_ flags
with NewDriverState |= ctx->DriverFlags.New*. This makes GL state
changes invoke exactly the update functions in drivers that are
affected by those changes.

The flags not touched are _NEW_BUFFERS, _NEW_PROGRAM, _NEW_TEXTURE_-
OBJECT, _NEW_POINT, and of course _NEW_ARRAY and _NEW_CURRENT_ATTRIB,
and a bunch of legacy ones. I think those are the only ones that should
invoke _mesa_update_state in the core profile.

There is a nice decrease in CPU overhead if the state changes only set
NewDriverState. If you add _NEW_TEXTURE or _NEW_PROGRAM, everything
else becomes just noise, because those two are the biggest ones.

The second patch shows some numbers as an example of what to expect.

The improvement with real apps is expected to be tiny.

Please review.

Thanks,
Marek