Re: [RFC PATCH 00/20] x86/intel_rdt: Start abstraction for a second arch

From: James Morse
Date: Fri Nov 30 2018 - 14:23:46 EST


Hi Yury,

On 27/11/2018 12:33, Yury Norov wrote:
> On Fri, Aug 24, 2018 at 11:44:59AM +0100, James Morse wrote:
>> ARM have some upcoming CPU features that are similar to Intel RDT. Resctrl
>> is the defacto ABI for this sort of thing, but it lives under arch/x86.
>>
>> To get existing software working, we need to make resctrl work with arm64.
>> This series is the first chunk of that. The aim is to move the filesystem/ABI
>> parts into /fs/resctrl, and implement a second arch backend.
>>
>>
>> What are the ARM features?
>> Future ARM SoCs may have a feature called MPAM: Memory Partitioning and
>> Monitoring. This is an umbrella term like RDT, and covers a range of controls
>> (like CAT) and monitors (like MBM, CMT).

>> This series is based on v4.18, and can be retrieved from:
>> git://linux-arm.org/linux-jm.git -b mpam/resctrl_rework/rfc_1
>
> Thank you a lot for this work on cache allocation.
>
> We are very interested in enabling CAT on Cavium / Marvell devices.
> Could you please share another two series you mentioned above?

I'm working on assembling the whole thing as Fenghua asked, there should be a
tree that shows the shape of the whole thing soon.


> Do you have a working ARM64 CAT driver? It will much help us in our
> experimenting.

For moving the arch-independent parts to /fs/, I'm afraid its all-or-nothing.
Abstracting just the 'CAT' parts will generate much more churn for both
architectures.


Thanks,

James