On Mon, Dec 14, 2020 at 06:25:34PM +0100, Peter Zijlstra wrote:
> On Mon, Dec 14, 2020 at 11:54:49PM +0800, Lai Jiangshan wrote:
> > From: Lai Jiangshan <la...@linux.alibaba.com>
> >
> > There might be other CPU online. The workers losing binding on its CPU
> > should have chance to work on those later onlined CPUs.
> >
> > Fixes: 06249738a41a ("workqueue: Manually break affinity on hotplug")
> > Signed-off-by: Lai Jiangshan <la...@linux.alibaba.com>
> > ---
> > kernel/workqueue.c | 3 ++-
> > 1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/kernel/workqueue.c b/kernel/workqueue.c
> > index aba71ab359dd..1f5b8385c0cf 100644
> > --- a/kernel/workqueue.c
> > +++ b/kernel/workqueue.c
> > @@ -4909,8 +4909,9 @@ static void unbind_workers(int cpu)
> >
> > raw_spin_unlock_irq(&pool->lock);
> >
> > + /* don't rely on the scheduler to force break affinity for us.
> > */
> > for_each_pool_worker(worker, pool)
> > - WARN_ON_ONCE(set_cpus_allowed_ptr(worker->task,
> > cpu_active_mask) < 0);
> > + WARN_ON_ONCE(set_cpus_allowed_ptr(worker->task,
> > cpu_possible_mask) < 0);
>
> Please explain this one.. it's not making sense. Also the Changelog
> doesn't seem remotely related to the actual change.
>
> Afaict this is actively wrong.
I think I was too tired, I see what you're doing now and it should work
fine, I still think the changelog could use help though.
