Re: [lttng-dev] [PATCH v2 05/12] urcu/uatomic: Add CMM memory model
"Paul E. McKenney via lttng-dev" <[email protected]>
| Newsgroups | org.lttng.lists.lttng-dev |
|---|---|
| Message-ID | <5a440c51-43d3-4be6-ba5a-215c9d3e960f@paulmck-laptop> |
On Thu, Jun 29, 2023 at 12:49:00PM -0400, Olivier Dion wrote: > On Wed, 21 Jun 2023, "Paul E. McKenney" <[email protected]> wrote: > > On Wed, Jun 07, 2023 at 02:53:52PM -0400, Olivier Dion wrote: > >> -#ifdef __URCU_DEREFERENCE_USE_ATOMIC_CONSUME > >> -# define _rcu_dereference(p) __extension__ ({ \ > >> - __typeof__(__extension__ ({ \ > >> - __typeof__(p) __attribute__((unused)) _________p0 = { 0 }; \ > >> - _________p0; \ > >> - })) _________p1; \ > >> - __atomic_load(&(p), &_________p1, __ATOMIC_CONSUME); \ > > > > There is talk of getting rid of memory_order_consume. But for the moment, > > it is what there is. Another alternative is to use a volatile load, > > similar to old-style CMM_LOAD_SHARED() or in-kernel READ_ONCE(). > > I think we can stick to __ATOMIC_CONSUME for now. Hopefully getting rid > of it means it will be an alias for __ATOMIC_ACQUIRE for ever. That seems emininently reasonable to me! Thanx, Paul _______________________________________________ lttng-dev mailing list [email protected] https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev