Re: [PATCH v1 2/5] perf/x86/intel/pt: IP filtering register/cpuid bits

From: Peter Zijlstra
Date: Thu Apr 21 2016 - 15:17:16 EST


On Thu, Apr 21, 2016 at 08:55:38PM +0200, Thomas Gleixner wrote:
> On Thu, 21 Apr 2016, Borislav Petkov wrote:
> > > +#define MSR_IA32_RTIT_ADDR0_A 0x00000580
> > > +#define MSR_IA32_RTIT_ADDR0_B 0x00000581
> > > +#define MSR_IA32_RTIT_ADDR1_A 0x00000582
> > > +#define MSR_IA32_RTIT_ADDR1_B 0x00000583
> > > +#define MSR_IA32_RTIT_ADDR2_A 0x00000584
> > > +#define MSR_IA32_RTIT_ADDR2_B 0x00000585
> > > +#define MSR_IA32_RTIT_ADDR3_A 0x00000586
> > > +#define MSR_IA32_RTIT_ADDR3_B 0x00000587
> >
> > So can we not turn msr-index.h a dumping ground for MSRs pls?
> >
> > If those are only PT-relevant, why not define them all in pt.h?
>
> I have to disagree here. The MSRs itself can really go into msr-index.h while
> the bit definitions might go elsewhere. What's wrong with having all MSRs at a
> central place?

So I agree with Thomas; the risk of not doing this is that we'll
introduce the same MSR again, in another file, under another name.

That's confusion we can do without.