Quoting Mika Kuoppala (2017-08-16 15:45:54) > Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> writes: > > > Part of the attraction of using a recursive batch is that it is > > hard on the system (executing the "function" call is apparently > > quite expensive). However, the GPU may hog the entire system for > > a few minutes, preventing even NMI. Quite why this is so is unclear, > > but presumably it relates to the PM_INTRMSK workaround on gen6/gen7. > > If we give the system a break by having the GPU execute a few nops > > between function calls, that appears enough to keep SNB out of > > trouble. > > > > Can we trip into the same pit with igt_hang? It has tight > recurse. Adding few noops makes the hangcheck sampler > to hit more sparsely and slow the verdict of hang. And a few others. The reason we stuck the invalid op in there in the first place was because we didn't have the PM_INTRMSK w/a in place and we could take out the system. It's that I fear is going wrong, but we always call gen6_sanitize_rps_pm_mask() now. Ville says that I915_WRITE(GEN6_RP_CONTROL, 0) is just as fatal. So we may have to rethink gen6_disable_rps(). -Chris _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
