drm_hwcomposer: limit maximum depth of display composition queue

SurfaceFlinger will destroy our layer handles if we don't use them after about
a second. To get around this issue, we block SurfaceFlinger on hwc_set if the
display composition queue is getting too large. This often happens during
the init of the GLWorker or during heavy GPU usage.

Change-Id: Idb4a3a81e0d3a2caf7f94e5515a19ec16a1c67e3
1 file changed