Re: [PATCH 1/2] amd: uncore: Rename cpufeatures macro for cache counters

[Natarajan, Janakarajan]

On 6/6/2017 11:31 AM, Borislav Petkov wrote:
> On Mon, Jun 05, 2017 at 11:13:18AM -0500, Janakarajan Natarajan wrote:
> > In Family 17h, L3 is the last level cache as opposed to L2 in previous
> > families. Avoid this name confusion and rename X86_FEATURE_PERFCT_L2 to
> > X86_FEATURE_PERFCTR_LLC to indicate the performance counter on the last
> > level of cache.
> >
> > Signed-off-by: Janakarajan Natarajan <Janakarajan.Natarajan@xxxxxxx>
> > ---
> >   arch/x86/events/amd/uncore.c       | 2 +-
> >   arch/x86/include/asm/cpufeatures.h | 2 +-
> >   2 files changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/arch/x86/events/amd/uncore.c b/arch/x86/events/amd/uncore.c
> > index 4d1f7f2d..8fea711 100644
> > --- a/arch/x86/events/amd/uncore.c
> > +++ b/arch/x86/events/amd/uncore.c
> > @@ -569,7 +569,7 @@ static int __init amd_uncore_init(void)
> >   		ret = 0;
> >   	}
> >   
> > -	if (boot_cpu_has(X86_FEATURE_PERFCTR_L2)) {
> > +	if (boot_cpu_has(X86_FEATURE_PERFCTR_LLC)) {
> >   		amd_uncore_llc = alloc_percpu(struct amd_uncore *);
> >   		if (!amd_uncore_llc) {
> >   			ret = -ENOMEM;
> > diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
> > index b04bb6d..da422d6 100644
> > --- a/arch/x86/include/asm/cpufeatures.h
> > +++ b/arch/x86/include/asm/cpufeatures.h
> > @@ -177,7 +177,7 @@
> >   #define X86_FEATURE_PERFCTR_NB  ( 6*32+24) /* NB performance counter extensions */
> >   #define X86_FEATURE_BPEXT	(6*32+26) /* data breakpoint extension */
> >   #define X86_FEATURE_PTSC	( 6*32+27) /* performance time-stamp counter */
> > -#define X86_FEATURE_PERFCTR_L2	( 6*32+28) /* L2 performance counter extensions */
> > +#define X86_FEATURE_PERFCTR_LLC	( 6*32+28) /* Last Level Cache performance counter extensions */
> Bah, the Zen PPR calls this PerfCtrExtL3 now. And F16h BKDG calls it
> PerfCtrExtL2I.
>
> Can this be fixed to be PerfCtrExtLLC in the docs so that there is no
> more confusion?

The PerfCtrExtL3 will be changed to PerfCtrExtLLC in the next PPR update.