[Glamor] glamor with current xserver Git

[Michel Dänzer]

On Mon, 2012-09-17 at 15:51 +0800, He Junyan wrote: 
> Hi:
> 
> I think we need to discuss this problem.
> 
> I trace this problem and find that this problem caused by the glx 
> extension of xserver.
> In the code of glx extension, it re-defines the symbols:
> 
> PUBLIC void _glapi_set_context(void *context)
> PUBLIC void *_glapi_get_context(void)
> PUBLIC void _glapi_set_dispatch(struct _glapi_table *dispatch)
> PUBLIC struct _glapi_table *_glapi_get_dispatch(void)
> PUBLIC int _glapi_add_dispatch(const char *const *function_names, const 
> char *parameter_signature)
> ....
> 
> These symbols can be found both in glx and mapi and collide with each 
> other,  and which one is called
> really depends on the loading sequence of libglx.so and libglapi.so .
> 
> Both glx and egl will call the APIs of  __DRIdri2Extension and 
> __DRIcoreExtension of dri drivers to create
> the screen and context, so the screen and context struct seems compatible.
> But for the getting the gl functions' address, they are not compatible.
> eglGetProcAddress will depend a gl function's stub which is established 
> by _glapi_add_dispatch, and the stub
> will call the really gl function in _glapi_table.  But 
> _glapi_add_dispatch in glx no not do this.
> glx use another manner to call functions in the _glapi_table.
> So in glamor, eglGetProcAddress just get invalid function address and 
> have error when call gl function.
> 
> I am creating the glx wrapper layer to fix this, but find glx define 
> another the _glapi_table struct and different
> from it in mapi.  This means call glx's gl function may be mapped to 
> wrong really gl function in mesa, so we still
> seem have some risk by this manner.

Hmm. I don't know enough about the dispatch mechanism to suggest a
solution. Can you bring this up on the xorg-devel mailing list?

Thanks for looking into it!


-- 
Earthling Michel Dänzer           |                   http://www.amd.com
Libre software enthusiast         |          Debian, X and DRI developer