On 2024-04-01 11:29 PM, James Houghton wrote: > This patchset adds a fast path in KVM to test and clear access bits on > sptes without taking the mmu_lock. It also adds support for using a > bitmap to (1) test the access bits for many sptes in a single call to > mmu_notifier_test_young, and to (2) clear the access bits for many ptes > in a single call to mmu_notifier_clear_young. How much improvement would we get if we _just_ made test/clear_young lockless on x86 and hold the read-lock on arm64? And then how much benefit does the bitmap look-around add on top of that?
