On Mon, Jun 26, 2023 at 10:59:40AM -0700, Alexei Starovoitov wrote:
> On Mon, Jun 26, 2023 at 10:55 AM David Vernet <void@xxxxxxxxxxxxx> wrote:
> >
> > > > > +
> > > > > + migrate_disable();
> > > > > + bpf_mem_cache_free_rcu(&bpf_cpumask_ma, cpumask);
> > > > > + migrate_enable();
> > > >
> > > > The fact that callers have to disable migration like this in order to
> > > > safely free the memory feels a bit leaky. Is there any reason we can't
> > > > move this into bpf_mem_{cache_}free_rcu()?
> > >
> > > migrate_disable/enable() are actually not necessary here.
> > > We can call bpf_mem_cache_free_rcu() directly from any kfunc.
> >
> > Could you please clarify why? Can't we migrate if the kfunc is called
> > from a sleepable struct_ops callback?
>
> migration is disabled for all bpf progs including sleepable.
Fair enough :-) Then yep, let's remove these. Feel free to do so when
you send v2, and keep my Ack. Otherwise I'm happy to send a follow-on
patch after this series is merged.
