On Wed, Oct 23, 2024 at 04:42:36PM -0700, Christoph Lameter (Ampere) wrote: > On Wed, 23 Oct 2024, Peter Zijlstra wrote: > > > > I doubt anybody will notice, and smp_load_acquire() is the future. Any > > > architecture that does badly on it just doesn't matter (and, as > > > mentioned, I don't think they even exist - "smp_rmb()" is generally at > > > least as expensive). > > > > Do we want to do the complementing patch and make write_seqcount_end() > > use smp_store_release() ? > > > > I think at least ARM (the 32bit thing) has wmb but uses mb for > > store_release. But I also think I don't really care about that. > > The proper instruction would be something like > > atomic_inc_release(&seqcount) It would not be, making the increment itself atomic would make the whole thing far more expensive.
