On 3/3/26 14:34, Thomas Hellström wrote: > GPU use-cases for mmu_interval_notifiers with hmm often involve > starting a gpu operation and then waiting for it to complete. > These operations are typically context preemption or TLB flushing. > > With single-pass notifiers per GPU this doesn't scale in > multi-gpu scenarios. In those scenarios we'd want to first start > preemption- or TLB flushing on all GPUs and as a second pass wait > for them to complete. > > One can do this on per-driver basis multiplexing per-driver > notifiers but that would mean sharing the notifier "user" lock > across all GPUs and that doesn't scale well either, so adding support > for multi-pass in the core appears to be the right choice. > > Implement two-pass capability in the mmu_interval_notifier. Use a > linked list for the final passes to minimize the impact for > use-cases that don't need the multi-pass functionality by avoiding > a second interval tree walk, and to be able to easily pass data > between the two passes.
Please CC all maintainers+reviewers that MAINTAINERS recommends you to cc. -- Cheers, David
