On 19/02/2016 16:04, Radim Krčmář wrote: >> > >> > ... so in patch 7 concurrent _writes_ of reinject are protected by the >> > lock, but reads are done outside it (in pit_timer_fn). WDYT about >> > making reinject an atomic_t? > There was/is no harm in having reinject non-atomic. This patch added > notifiers, which is the reason for re-introducing a mutex. > > Userspace can (and SHOULDN'T) call this function multiple times, > concurrently, so the mutex prevents a situations where, e.g. only one > notifier is registered in the end.
Yes, I understand why you added the mutex here; good catch indeed. The atomic_t is just to show that it's okay to read it outside the lock. It's just for a bit of extra documentation. Paolo
