Re: FW: [PATCH 4/6] hwmon: amd_energy: let user enable/disable the sw accumulation

Guenter Roeck
2020-09-08T16:36:38Z

On Tue, Sep 08, 2020 at 09:51:23PM +0530, Naveen Krishna Ch wrote:
> Hi Guenter
>
> On Tue, 8 Sep 2020 at 21:42, Chatradhi, Naveen Krishna
> <NaveenKrishna.Chatradhi@amd.com> wrote:
> >
> > [AMD Public Use]
> >
> > [CAUTION: External Email]
> >
> > On 9/5/20 8:17 AM, Guenter Roeck wrote:
> > > On 9/5/20 7:32 AM, Naveen Krishna Chatradhi wrote:
> > >> Provide an option "accumulator_status" via sysfs to enable/disable
> > >> the software accumulation of energy counters.
> > >>
> > >> Signed-off-by: Naveen Krishna Chatradhi <nchatrad@amd.com>
> > >
> > > I am quite substantially opposed to this. I'd be willing to accept a
> > > module parameter. However, the code is there, and it is enabled by
> > > default, and it should stay enabled by default.
> Sure, I will change it back.
>
> > > I don't want to have to deal with people complaining that it suddenly
> > > no longer works.
> Understood.
> > >
> > > Also, there needs to be an explanation for why this is needed.
> > >
> >
> > No, wait, without accumulator this driver has zero value.
> > Users should just not load the driver if they don't want the overhead associated with accumulation.
>
> The use case we have is to provide an interface to enable/disable
> accumulation by the admins, without having to reboot or install
> something.
> A userspace API is provided which will be used by the applications.
>

Really, that should not be done. If accumulation is not wanted, the
driver is pointless and should be unloaded (or not be loaded to start
with).

Guenter