So with compiz on Intel hw with fake bufmgr, opening 4 firefox windows at 1680x1050 and hitting alt-tab, could cause the batchbuffer to try and reference more than the 32MB of RAM allocated.
Fix 1:
Fix 1 is to pre-verify the list of buffers against the current batchbuffer and if it can't possibly fit in the aperture to flush the batchbuffer to the hardware
and try again. If the buffers still can't fit well then you are hosed as I'm not sure there is a nice way to tell anyone.
Fix 2:
Next problem was that even with a simple check for total < aperture, we ran
into fragmentation issues, this meant that half way down a set of buffers,
we would fail as no blocks were available. Fix this by nuking the memory
manager from orbit and letting it start again and relayout the blocks in a
manner that fits.
Fix 3:
Finally the initial problem we were seeing was a memcpy to a NULL backing store.
We seem to end up with a texture at some point that never gets mapped but ends up with data in it. compiz al-tab icons have this property. So I created a card dirty bit that memcpy's any buffer that is !static and is written to back to memory. This probably is wrong but it makes compiz work for now.
Caveats:
965 support is still fail.
due to the two read ports limit into temp memory may need the MAD_2 instruction
for the second instruction of the decomposed XPD.
While here, also try to avoid MAD_2 for MAD if all 3 inputs are temps but the
temps aren't actually distinct.
Fixes compiz with direct rendering when both GLX_TEXTURE_2D_EXT and
GLX_TEXTURE_RECTANGLE_EXT are supported for a GLXPixmap and the
application didn't specify the texture target as a GLX drawable attribute
when creating the GLX drawable.
The autoconf macro AC_PATH_PROGS handles the case of searching for
multiple program names already, so we don't need to open code it. Also
changed the search to AC_CHECK_PROGS so that it doesn't set the full
path unless the user specified. Finally, report back the found value at
the end for what the user should run.
Add DRI2 direct rendering support to libGL and add DRI2 client side
protocol code. Extend the GLX 1.3 create drawable functions in
glx_pbuffer.c to call into the DRI driver when possible.
Introduce __DRIconfig, opaque struct that represents a DRI driver
configuration. Get's rid of the open coded __GLcontextModes in the
DRI driver interface and the context modes create and destroy
functions that the loader was requires to provide. glcore.h is no
longer part of the DRI driver interface. The DRI config is GL binding
agnostic, that is, not specific to GLX, EGL or other bindings.
The core API is now also an extension, and the driver exports a list
of extensions as the symbol __driDriverExtensions, which the loader
must dlsym() for. The list of extension will always include the DRI
core extension, which allows creating and manipulating DRI screens,
drawables and contexts. The DRI legacy extension, when available,
provides alternative entry points for creating the DRI objects that
work with the XF86DRI infrastructure.
Change DRI2 client code to not use drm drawables or contexts. We
never used drm_drawable_t's and the only use for drm_context_t was as
a unique identifier when taking the lock. We now just allocate a
unique lock ID out of the DRILock sarea block. Once we get rid of the
lock entirely, we can drop this hack.
Change the interface between dri_util.c and the drivers, so that the
drivers now export the DriverAPI struct as driDriverAPI instead of the
InitScreen entry point. This lets us avoid dlsym()'ing for the DRI2
init screen function to see if DRI2 is supported by the driver.
