RE: [PATCH V3 2/4] x86/resctrl: Enumerate per-thread MBA

[Babu Moger]

> -----Original Message-----
> From: Reinette Chatre <reinette.chatre@xxxxxxxxx>
> Sent: Thursday, May 14, 2020 3:12 PM
> To: Moger, Babu <Babu.Moger@xxxxxxx>; tglx@xxxxxxxxxxxxx;
> fenghua.yu@xxxxxxxxx; bp@xxxxxxxxx; tony.luck@xxxxxxxxx
> Cc: kuo-lang.tseng@xxxxxxxxx; ravi.v.shankar@xxxxxxxxx; mingo@xxxxxxxxxx;
> hpa@xxxxxxxxx; x86@xxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH V3 2/4] x86/resctrl: Enumerate per-thread MBA
> 
> Hi Babu,
> 
> On 5/14/2020 12:04 PM, Babu Moger wrote:
> >
> >
> >> -----Original Message-----
> >> From: Reinette Chatre <reinette.chatre@xxxxxxxxx>
> >> Sent: Wednesday, May 6, 2020 6:50 PM
> >> To: tglx@xxxxxxxxxxxxx; fenghua.yu@xxxxxxxxx; bp@xxxxxxxxx;
> >> tony.luck@xxxxxxxxx
> >> Cc: kuo-lang.tseng@xxxxxxxxx; ravi.v.shankar@xxxxxxxxx;
> mingo@xxxxxxxxxx;
> >> Moger, Babu <Babu.Moger@xxxxxxx>; hpa@xxxxxxxxx; x86@xxxxxxxxxx;
> >> linux-kernel@xxxxxxxxxxxxxxx; Reinette Chatre <reinette.chatre@xxxxxxxxx>
> >> Subject: [PATCH V3 2/4] x86/resctrl: Enumerate per-thread MBA
> >>
> >> From: Fenghua Yu <fenghua.yu@xxxxxxxxx>
> >>
> 
> ...
> 
> >> diff --git a/arch/x86/kernel/cpu/scattered.c
> b/arch/x86/kernel/cpu/scattered.c
> >> index 62b137c3c97a..bccfc9ff3cc1 100644
> >> --- a/arch/x86/kernel/cpu/scattered.c
> >> +++ b/arch/x86/kernel/cpu/scattered.c
> >> @@ -35,6 +35,7 @@ static const struct cpuid_bit cpuid_bits[] = {
> >>  	{ X86_FEATURE_CDP_L3,		CPUID_ECX,  2, 0x00000010, 1
> >> },
> >>  	{ X86_FEATURE_CDP_L2,		CPUID_ECX,  2, 0x00000010, 2
> >> },
> >>  	{ X86_FEATURE_MBA,		CPUID_EBX,  3, 0x00000010, 0 },
> >> +	{ X86_FEATURE_PER_THREAD_MBA,	CPUID_ECX,  0, 0x00000010, 3
> >> },
> >
> > This is a CPUID feature. You can actually detect this feature without
> > checking vendor model in patch @1. This patch looks good to me.
> >
> 
> This feature is different from the feature introduced in patch 1.

Ok.  I mis-understood that.