On 23/06/2022 11:27, Tvrtko Ursulin
wrote:
After a vm_unbind, UMD can re-bind to same VA range against an active VM.
Though I am not sue with Mesa usecase if that new mapping is required for
running GPU job or it will be for the next submission. But ensuring the
tlb flush upon unbind, KMD can ensure correctness.
Isn't that their problem? If they re-bind for submitting _new_ work then they get the flush as part of batch buffer pre-amble.
In the non sparse case, if a VA range is unbound, it is invalid to use that range for anything until it has been rebound by something else.
We'll take the fence provided by vm_bind and put it as a wait fence on the next execbuffer.
It might be safer in case of memory over fetching?
TLB flush will have to happen at some point right?
What's the alternative to do it in unbind?
-Lionel
