[PATCH v7 08/22] cpuset: Don't use the cpu_possible_mask as a last resort for cgroup v1

[Will Deacon]

On Wed, May 26, 2021 at 05:02:20PM +0200, Peter Zijlstra wrote:
> On Tue, May 25, 2021 at 04:14:18PM +0100, Will Deacon wrote:
> >  void cpuset_cpus_allowed_fallback(struct task_struct *tsk)
> >  {
> > +	const struct cpumask *cs_mask;
> > +	const struct cpumask *possible_mask = task_cpu_possible_mask(tsk);
> > +
> >  	rcu_read_lock();
> > +	cs_mask = task_cs(tsk)->cpus_allowed;
> > +
> > +	if (!is_in_v2_mode() || !cpumask_subset(cs_mask, possible_mask))
> > +		goto unlock; /* select_fallback_rq will try harder */
> > +
> > +	do_set_cpus_allowed(tsk, cs_mask);
> > +unlock:
> 
> 	if (is_in_v2_mode() && cpumask_subset(cs_mask, possible_mask))
> 		do_set_cpus_allowed(tsk, cs_mask);
> 
> perhaps?

Absolutely.

Will