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From:   Peter Newman <peternewman@google.com>
Date:   Wed, 25 Oct 2023 23:06:20 +0200
Message-ID: <CALPaoCj72V=o60tqsFMRzaeUw-1+rN7pyhsdCyVEV=0tN_CZ7A@mail.gmail.com>
Subject: Re: [PATCH] x86/resctrl: mba_MBps: Fall back to total b/w if local
 b/w unavailable
To:     Tony Luck <tony.luck@intel.com>
Cc:     Fenghua Yu <fenghua.yu@intel.com>,
        Reinette Chatre <reinette.chatre@intel.com>,
        Jonathan Corbet <corbet@lwn.net>,
        Shuah Khan <skhan@linuxfoundation.org>, x86@kernel.org,
        Shaopeng Tan <tan.shaopeng@fujitsu.com>,
        James Morse <james.morse@arm.com>,
        Jamie Iles <quic_jiles@quicinc.com>,
        Babu Moger <babu.moger@amd.com>,
        Randy Dunlap <rdunlap@infradead.org>,
        linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org,
        patches@lists.linux.dev
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Hi Tony,

On Wed, Oct 25, 2023, 21:38 Tony Luck <tony.luck@intel.com> wrote:
>
> On Wed, Oct 25, 2023 at 02:46:53PM +0200, Peter Newman wrote:
>
> > > +static struct mbm_state *get_mbm_data(struct rdt_domain *dom_mbm, int rmid)
> > > +{
> > > +       if (is_mbm_local_enabled())
> > > +               return &dom_mbm->mbm_local[rmid];
> > > +
> > > +       return &dom_mbm->mbm_total[rmid];
> > > +}
> >
> > That looks very similar to the get_mbm_state() function I added to
> > this same file recently:
> >
> > https://lore.kernel.org/all/20221220164132.443083-2-peternewman%40google.com
> >
> > I think the name you picked is misleadingly general. "local if
> > available, otherwise total" seems to be a choice specific to the mbps
> > controller. I think these functions should be reconciled a little
> > better.
> >
>
> Peter (and Babu, who made the same point about get_mbm_state().
>
> Do you want to see your function extended to do the "pick an MBM event?"

What I meant was I think it would be enough to just give the function
you added a name that's more specific to the Mbps controller use case.
For example, get_mba_sc_mbm_state().

It's only problematic that you added a function with an equivalent
name to an existing function that does something different.

-Peter