Re: [RFC][PATCH 6/7] freelist: Lock less freelist

From: Cameron
Date: Thu Aug 27 2020 - 15:57:43 EST


On Thu, Aug 27, 2020 at 3:08 PM Boqun Feng <boqun.feng@xxxxxxxxx> wrote:
> So if try_cmpxchg_acquire() fails, we don't have ACQUIRE semantics on
> read of the new list->head, right? Then probably a
> smp_mb__after_atomic() is needed in that case?

Yes, there needs to be an acquire on the head after a failed cmpxchg;
does the atomic_fetch_add following that not have acquire semantics?

Cameron