Re: [PATCH v1 09/20] x86/resctrl: Abstract and use supports_mba_mbps()

From: James Morse
Date: Fri Oct 01 2021 - 12:01:40 EST


Hi Shaopeng Tan,

On 24/09/2021 07:23, tan.shaopeng@xxxxxxxxxxx wrote:
>> To determine whether the mba_mbps option to resctrl should be supported,
>> resctrl tests the boot cpus' x86_vendor.
>>
>> This isn't portable, and needs abstracting behind a helper so this check can be
>> part of the filesystem code that moves to /fs/.
>>
>> Re-use the tests set_mba_sc() does to determine if the mba_sc is supported
>> on this system. An 'alloc_capable' test is added so that this property isn't
>> implied by 'linear'.

>> diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
>> b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
>> index e321ea5de562..4388685548a0 100644
>> --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
>> +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
>> @@ -2317,7 +2326,7 @@ static int rdt_parse_param(struct fs_context *fc,
>> struct fs_parameter *param)
>> ctx->enable_cdpl2 = true;
>> return 0;
>> case Opt_mba_mbps:
>> - if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
>> + if (supports_mba_mbps())
>> return -EINVAL;
> I think if(!supports_mba_mbps()) is correct, isn't it?

Ooops!

(looks like I messed this up when fixing the name)


Thanks,

James