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

Reinette Chatre
2020-05-14T20:12:04Z

Hi Babu,

On 5/14/2020 12:04 PM, Babu Moger wrote:
>
>
>> -----Original Message-----
>> From: Reinette Chatre <reinette.chatre@intel.com>
>> Sent: Wednesday, May 6, 2020 6:50 PM
>> To: tglx@linutronix.de; fenghua.yu@intel.com; bp@alien8.de;
>> tony.luck@intel.com
>> Cc: kuo-lang.tseng@intel.com; ravi.v.shankar@intel.com; mingo@redhat.com;
>> Moger, Babu <Babu.Moger@amd.com>; hpa@zytor.com; x86@kernel.org;
>> linux-kernel@vger.kernel.org; Reinette Chatre <reinette.chatre@intel.com>
>> Subject: [PATCH V3 2/4] x86/resctrl: Enumerate per-thread MBA
>>
>> From: Fenghua Yu <fenghua.yu@intel.com>
>>

...

>> 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.

Reinette