[PATCH] riscv: cpu-hotplug: clear cpu from numa map when teardown

[Pingfan Liu]

On Wed, Feb 9, 2022 at 9:13 AM Palmer Dabbelt <palmer at dabbelt.com> wrote:
>
> On Sun, 23 Jan 2022 04:13:52 PST (-0800), kernelfans at gmail.com wrote:
> > There is numa_add_cpu() when cpus online, accordingly, there should be
> > numa_remove_cpu() when cpus offline.
> >
> > Signed-off-by: Pingfan Liu <kernelfans at gmail.com>
> > Cc: Paul Walmsley <paul.walmsley at sifive.com>
> > Cc: Palmer Dabbelt <palmer at dabbelt.com>
> > Cc: Albert Ou <aou at eecs.berkeley.edu>
> > Cc: Jisheng Zhang <jszhang at kernel.org>
> > To: linux-riscv at lists.infradead.org
> > ---
> >  arch/riscv/kernel/cpu-hotplug.c | 1 +
> >  1 file changed, 1 insertion(+)
> >
> > diff --git a/arch/riscv/kernel/cpu-hotplug.c b/arch/riscv/kernel/cpu-hotplug.c
> > index be7f05b542bb..78d156a359ef 100644
> > --- a/arch/riscv/kernel/cpu-hotplug.c
> > +++ b/arch/riscv/kernel/cpu-hotplug.c
> > @@ -40,6 +40,7 @@ int __cpu_disable(void)
> >               return ret;
> >
> >       remove_cpu_topology(cpu);
> > +     numa_remove_cpu(cpu);
> >       set_cpu_online(cpu, false);
> >       irq_migrate_all_off_this_cpu();
>
> Thanks, this is on fixes.  I don't really have any NUMA-related test
> setups, but if someone has a QEMU-based config that's meaningful then
> I'm happy to add it.

Sorry that I have no such things even riscv machine. I did some
hotplug stuff, compared arm/arm64/riscv, and found the difference.

But since the code path should be symmetric, I think the hot-removing
path should revert the hot-adding path.

Thanks,

Pingfan