[Intel-gfx] [PATCH xf96-video-intel] DRI2GetMSC: Do not send a bogus ust when no drawable is not displayed

[Chris Wilson]

On Fri, Mar 29, 2013 at 01:54:37PM +0800, Daniel Kurtz wrote:
> According to the opengl glx_sync_control spec, the Unadjusted System Time
> (or UST) is a 64-bit monotonically increasing counter that is available
> throughout the system:
> http://www.opengl.org/registry/specs/OML/glx_sync_control.txt
> 
> Therefore, sending 0, even in this corner case, is out of spec.
> Instead, just return FALSE indicating that the operation could not be
> completed.

The problem is that ends up sending BadDrawable back to the client,
which ends up killing many clients and a compositor or two due to the
unexpected error.

Would you prefer querying pipe 0 in this case for the UST?
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre