Does gbm_bo_map() implicitly synchronise?

[Pierre Ossman]

On 15/06/2024 13:35, Marek Olšák wrote:
> It's probably driver-specific. Some drivers might need glFlush before
> you use gbm_bo_map because gbm might only wait for work that has been
> flushed.
> 

That would be needed on the "writing" side, right? So if I'm seeing 
issues when mapping for reading, then it would indicate a bug in the 
other peer? Which would be gnome-shell in my case.

Any way I could test this? Can I force extra syncs/flushes in some way 
and see if the issue goes away?

I tried adding a sleep of 10ms before reading the data, but did not see 
any improvement. Which would make sense if the commands are still 
sitting in an application buffer somewhere, rather than with the GPU.

Regards
-- 
Pierre Ossman           Software Development
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