[igt-dev] [PATCH i-g-t] tests/perf: Fix timeout for RC6 re-enabling

[Chris Wilson]

Quoting Imre Deak (2019-04-16 14:51:35)
> After closing the perf stream the parking the GPU engines may easily
> take more than 1 second: releasing the FD itself results in a new
> request submission via i915_perf_release()->i915_oa_stream_destroy()->
> gen8_disable_metric_set(). That means a >1sec delay for the delayed
> unpark to be called due to the delay from

igt_drop_caches_set(DROP_IDLE);

flushes the idle work handler immediately, though you will probably want
DROP_ACTIVE | DROP_RETIRE to complete the picture, see
gem_quiescent_gpu().
-Chris