On 15/04/21 10:59, Peter Zijlstra wrote:
> Can't make sense of what I did.. I've removed that hunk. Patch now looks
> like this.
>
Small nit below, but regardless feel free to apply to the whole lot:
Reviewed-by: Valentin Schneider <valentin.schnei...@arm.com>
@VincentD, ISTR you had tested the initial version of this with your fancy
shmancy hotplug rollback stresser. Feel like doing this
> So instead, make sure balance_push is enabled between
> sched_cpu_deactivate() and sched_cpu_activate() (eg. when
> !cpu_active()), and gate it's utility with cpu_dying().
I'd word that "is enabled below sched_cpu_activate()", since
sched_cpu_deactivate() is now out of the picture.
[...]
> @@ -7639,6 +7639,9 @@ static DEFINE_PER_CPU(struct cpu_stop_wo
>
> /*
> * Ensure we only run per-cpu kthreads once the CPU goes !active.
> + *
> + * This is active/set between sched_cpu_deactivate() / sched_cpu_activate().
Ditto
> + * But only effective when the hotplug motion is down.
> */
> static void balance_push(struct rq *rq)
> {
