We need to throttle swaps here in addition to when the context is made
current to avoid causing problems with clients that just swap.
Throttling here also ensures our swaps get ordered as long as we block
the client occasionally.
Reported-by: Mario Kleiner <mario.kleiner@tuebingen.mpg.de>
Reviewed-by: Mario Kleiner <mario.kleiner@tuebingen.mpg.de>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
0294ff2a5c