Re: [patch v3 18/36] [patch V2 18/38] cpu/hotplug: Add CPU state tracking and synchronization

Peter Zijlstra
2023-05-09T11:09:07Z

On Mon, May 08, 2023 at 09:43:55PM +0200, Thomas Gleixner wrote:

> +static inline void cpuhp_ap_update_sync_state(enum cpuhp_sync_state state)
> +{
> + atomic_t *st = this_cpu_ptr(&cpuhp_state.ap_sync_state);
> + int sync = atomic_read(st);
> +
> + while (!atomic_try_cmpxchg(st, &sync, state));
> +}

Why isn't:

atomic_set(st, state);

any good?