| Date | Tue, 30 Jul 2019 09:22:40 -0400 | From | Steven Rostedt <> | Subject | Re: [RFC][PATCH 02/13] stop_machine: Fix stop_cpus_in_progress ordering |
| |
On Fri, 26 Jul 2019 16:54:11 +0200 Peter Zijlstra <peterz@infradead.org> wrote:
> Make sure the entire for loop has stop_cpus_in_progress set.
> kernel/stop_machine.c | 2 ++ > 1 file changed, 2 insertions(+) > > --- a/kernel/stop_machine.c > +++ b/kernel/stop_machine.c > @@ -383,6 +383,7 @@ static bool queue_stop_cpus_work(const s > */ > preempt_disable(); > stop_cpus_in_progress = true; > + barrier();
Like smp_mb() shouldn't barrier() have a comment to what is being ordered and why?
-- Steve
> for_each_cpu(cpu, cpumask) { > work = &per_cpu(cpu_stopper.stop_work, cpu); > work->fn = fn; > @@ -391,6 +392,7 @@ static bool queue_stop_cpus_work(const s > if (cpu_stop_queue_work(cpu, work)) > queued = true; > } > + barrier(); > stop_cpus_in_progress = false; > preempt_enable(); > >
|