config [31mCONFIG_DRM_I915_USERFAULT_AUTOSUSPEND[0m int "Runtime autosuspend delay for userspace GGTT mmaps (ms)" default 250 # milliseconds help On runtime suspend, as we suspend the device, we have to revoke userspace GGTT mmaps and force userspace to take a pagefault on their next access. The revocation and subsequent recreation of the GGTT mmap can be very slow and so we impose a small hysteris that complements the runtime-pm autosuspend and provides a lower floor on the autosuspend delay. May be 0 to disable the extra delay and solely use the device level runtime pm autosuspend delay tunable. config [31mCONFIG_DRM_I915_SPIN_REQUEST[0m int "Busywait for request completion (us)" default 5 # microseconds help Before sleeping waiting for a request (GPU operation) to complete, we may spend some time polling for its completion. As the IRQ may take a non-negligible time to setup, we do a short spin first to check if the request will complete in the time it would have taken us to enable the interrupt. May be 0 to disable the initial spin. In practice, we estimate the cost of enabling the interrupt (if currently disabled) to be a few microseconds. |