Re: [PATCH] x86/split_lock: Enumerate split lock feature on Sapphire Rapids

From: Peter Zijlstra
Date: Thu Jul 16 2020 - 15:50:29 EST


On Thu, Jul 16, 2020 at 12:37:00PM -0700, Fenghua Yu wrote:
> Hi, Thomas, Boris, Ingo,
>
> On Fri, Jun 26, 2020 at 02:55:34PM -0700, Fenghua Yu wrote:
> > Add Sapphire Rapids processor to CPU list to enumerate split lock
> > feature.
> >
> > Signed-off-by: Fenghua Yu <fenghua.yu@xxxxxxxxx>
> > Reviewed-by: Tony Luck <tony.luck@xxxxxxxxx>
> > ---
> > arch/x86/kernel/cpu/intel.c | 1 +
> > 1 file changed, 1 insertion(+)
> >
> > diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
> > index c25a67a34bd3..dca069ad6671 100644
> > --- a/arch/x86/kernel/cpu/intel.c
> > +++ b/arch/x86/kernel/cpu/intel.c
> > @@ -1148,6 +1148,7 @@ static const struct x86_cpu_id split_lock_cpu_ids[] __initconst = {
> > X86_MATCH_INTEL_FAM6_MODEL(ATOM_TREMONT_L, 1),
> > X86_MATCH_INTEL_FAM6_MODEL(TIGERLAKE_L, 1),
> > X86_MATCH_INTEL_FAM6_MODEL(TIGERLAKE, 1),
> > + X86_MATCH_INTEL_FAM6_MODEL(SAPPHIRERAPIDS_X, 1),
> > {}
> > };
>
> Any comment on this patch?

The only comment I have is that us needing it is ludicrous :/ What's the
bloody point of having it 'enumerated' if you then still have to use FMS
lists.

There's nowhere near enough cursing in the comment that goes with that
list.