Re: [RFC PATCH 03/19] fs/resctrl: Add new interface max_bandwidth

[Moger, Babu]

Hi Reinette,

Thanks for the comments. Will try to respond one by one.

On 2/6/2026 5:58 PM, Reinette Chatre wrote:
> Hi Babu,
>
> On 1/21/26 1:12 PM, Babu Moger wrote:
> > While min_bandwidth is exposed for each resource under
> > /sys/fs/resctrl, the maximum supported bandwidth is not currently shown.
> >
> > Add max_bandwidth to report the maximum bandwidth permitted for a resource.
> > This helps users understand the limits of the associated resource control
> > group.
> >
> > Signed-off-by: Babu Moger <babu.moger@xxxxxxx>
> > ---
>
> With resctrl fs being used by several architectures we should take care that
> interface changes take all planned usages into account.
>
> As shared at LPC [1] and email [2] we are already trying to create an interface
> that works for everybody and it already contains a way to expose the maximum
> bandwidth to user space. You attended that LPC session and [2] directed to you
> received no response. This submission with a different interface is unexpected.

Thanks for pointing this out. Yes. I missed that thread.

> Reinette
>
> [1] https://lpc.events/event/19/contributions/2093/attachments/1958/4172/resctrl%20Microconference%20LPC%202025%20Tokyo.pdf
> [2] https://lore.kernel.org/lkml/fb1e2686-237b-4536-acd6-15159abafcba@xxxxxxxxx/

I need to look into this much closely. Our current plan is to support MB 
and GMBA with L3 scope. So, with that in mind, I am not seeing a use 
case in that context for now. I can remove exposing max_bandwidth until 
we have a unified approach.

Thanks
Babu