On 05/07/2018 14:22, Raslan, KarimAllah wrote: >> They don't support atomics on double-word data. > But they support atomics on single words. Of which there are two. > We don't need atomic updates of the whole 64-bit quantity (a là > cmpxchg). Do we strictly need this to be atomic accross the 64-bit? > > Looking at the use cases for "requests": > > kvm_clear_request > kvm_test_request > kvm_request_pending > kvm_check_request > > ... and all of them would still work if the atomicity is only at the > word level, right? > Good point! Then yes, requests can be made 64 bit wide. Paolo
