Re: [Nouveau] [PATCH 06/38] x86/mmiotrace: Replace deprecated CPU-hotplug functions.

From: Karol Herbst
Date: Tue Aug 03 2021 - 11:03:54 EST


On Tue, Aug 3, 2021 at 4:25 PM Sebastian Andrzej Siewior
<bigeasy@xxxxxxxxxxxxx> wrote:
>
> The functions get_online_cpus() and put_online_cpus() have been
> deprecated during the CPU hotplug rework. They map directly to
> cpus_read_lock() and cpus_read_unlock().
>
> Replace deprecated CPU-hotplug functions with the official version.
> The behavior remains unchanged.
>
> Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
> Cc: Ingo Molnar <mingo@xxxxxxxxxx>
> Cc: Karol Herbst <karolherbst@xxxxxxxxx>
> Cc: Pekka Paalanen <ppaalanen@xxxxxxxxx>
> Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
> Cc: Andy Lutomirski <luto@xxxxxxxxxx>
> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> Cc: Borislav Petkov <bp@xxxxxxxxx>
> Cc: x86@xxxxxxxxxx
> Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
> Cc: nouveau@xxxxxxxxxxxxxxxxxxxxx
> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
> ---
> arch/x86/mm/mmio-mod.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/arch/x86/mm/mmio-mod.c b/arch/x86/mm/mmio-mod.c
> index cd768dafca9e9..933a2ebad471b 100644
> --- a/arch/x86/mm/mmio-mod.c
> +++ b/arch/x86/mm/mmio-mod.c
> @@ -376,12 +376,12 @@ static void enter_uniprocessor(void)
> goto out;
> }
>
> - get_online_cpus();
> + cpus_read_lock();
> cpumask_copy(downed_cpus, cpu_online_mask);
> cpumask_clear_cpu(cpumask_first(cpu_online_mask), downed_cpus);
> if (num_online_cpus() > 1)
> pr_notice("Disabling non-boot CPUs...\n");
> - put_online_cpus();
> + cpus_read_unlock();
>
> for_each_cpu(cpu, downed_cpus) {
> err = remove_cpu(cpu);
> --
> 2.32.0
>

Reviewed-by: Karol Herbst <kherbst@xxxxxxxxxx>