linux-kernel - Re: [PATCH v6 13/14] Documentation/x86: Rename and update intel_rdt

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Message-ID: <88595cc1-804f-c697-9cba-be40b9df7e39@amd.com>
Date:   Tue, 6 Nov 2018 19:03:01 +0000
From:   "Moger, Babu" <Babu.Moger@....com>
To:     Matthew Wilcox <willy@...radead.org>
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Subject: Re: [PATCH v6 13/14] Documentation/x86: Rename and update
 intel_rdt_ui.txt

Hi Matthew,

On 11/6/18 11:41 AM, Matthew Wilcox wrote:
> On Tue, Nov 06, 2018 at 07:53:05AM -0800, Matthew Wilcox wrote:
>>> -This feature is enabled by the CONFIG_INTEL_RDT Kconfig and the
>>> -X86 /proc/cpuinfo flag bits:
>>> +This feature is enabled by the CONFIG_INTEL_RDT Kconfig(for Intel) or
>>> +CONFIG_AMD_QOS(for AMD) and the X86 /proc/cpuinfo flag bits:
>>
>> Now I'm curious why we have two different Kconfig options for the same
>> feature.  I should go and read the other patches, I suppose.
> 
> Now that I've read through them, I find nowhere that the choices:
> 
> AMQ_QOS=y INTEL_RDT=n
> AMD_QOS=n INTEL_RDT=y
> AMD_QOS=y INTEL_RDT=y
> 
> have any difference to the resulting code.  Thus, this looks like a
> vanity config option; please don't do this.  Rename the config option
> to be vendor-neutral if you must, but please no new options unless
> absolutely necessary.
> 

Yes. That is right. Code does not change with any of these combinations.
We can go with only one neutral parameter which is config RESCTRL. I will
remove AMD_QOS and INTEL_RDT. This also requires some text changes to
cover both Intel and AMD. Will send the updated patches.