RE: [PATCH v7 12/13] selftests/resctrl: Disable MBA and MBM tests for AMD

From: Yu, Fenghua
Date: Fri May 10 2019 - 15:31:18 EST

> On Friday, May 10, 2019 10:40 AM
> Andre Przywara [mailto:andre.przywara@xxxxxxx] wrote:
> To: Yu, Fenghua <fenghua.yu@xxxxxxxxx>
> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>; Ingo Molnar
> <mingo@xxxxxxxxxx>; Borislav Petkov <bp@xxxxxxxxx>; H Peter Anvin
> <hpa@xxxxxxxxx>; Luck, Tony <tony.luck@xxxxxxxxx>; Chatre, Reinette
> <reinette.chatre@xxxxxxxxx>; Shankar, Ravi V <ravi.v.shankar@xxxxxxxxx>;
> Shen, Xiaochen <xiaochen.shen@xxxxxxxxx>; Pathan, Arshiya Hayatkhan
> <arshiya.hayatkhan.pathan@xxxxxxxxx>; Prakhya, Sai Praneeth
> <sai.praneeth.prakhya@xxxxxxxxx>; Babu Moger <babu.moger@xxxxxxx>;
> linux-kernel <linux-kernel@xxxxxxxxxxxxxxx>; James Morse
> <James.Morse@xxxxxxx>
> Subject: Re: [PATCH v7 12/13] selftests/resctrl: Disable MBA and MBM tests
> for AMD
> On Sat, 9 Feb 2019 18:50:41 -0800
> Fenghua Yu <fenghua.yu@xxxxxxxxx> wrote:
> Hi,
> > From: Babu Moger <babu.moger@xxxxxxx>
> >
> > For now, disable MBA and MBM tests for AMD. Deciding test pass/fail is
> > not clear right now. We can enable when we have some clarity.
> I don't think this is the right way. The availability of features should be
> queryable, for instance by looking into /sys/fs/resctrl/info. Checking for a
> certain vendor to skip tests just sounds wrong to me, and is definitely not
> scalable or future proof.
> We should really check the availability of a feature, then skip the whole
> subsystem test in resctrl_tests.c.

Babu may correct if I'm wrong: AMD does support the MBA and MBM features. So if querying the info directory, the features are there. But AMD doesn't want to support the testing for the features in the current patch set. They may support the testing in the future.