> On Jul 19, 2019, at 11:48 AM, Dave Hansen <dave.han...@intel.com> wrote: > > On 7/19/19 11:43 AM, Nadav Amit wrote: >> Andy said that for the lazy tlb optimizations there might soon be more >> shared state. If you prefer, I can move is_lazy outside of tlb_state, and >> not set it in any alternative struct. > > I just wanted to make sure that we capture these rules: > > 1. If the data is only ever accessed on the "owning" CPU via > this_cpu_*(), put it in 'tlb_state'. > 2. If the data is read by other CPUs, put it in 'tlb_state_shared'. > > I actually like the idea of having two structs.
Yes, that’s exactly the idea. In the (1) case, we may even be able to mark the struct with __thread qualifier, which IIRC would prevent memory barriers from causing these values being reread.
