Re: [RFC v2] arm,x86,fs/resctrl: Generic schema description Proof of Concept

[Luck, Tony]

On Wed, Aug 05, 2026 at 04:57:04PM -0700, Reinette Chatre wrote:
> Hi Ben,
> 
> On 8/5/26 9:59 AM, Ben Horgan wrote:
> > Just given a go at running this on a model with MPAM and I can mount resctrl with this
> > small patch to initialise the emulated_by lists so that list_empty() behaves.
> > 
> > diff --git a/drivers/resctrl/mpam_resctrl.c b/drivers/resctrl/mpam_resctrl.c
> > index 21dcbf5764cc..638095649151 100644
> > --- a/drivers/resctrl/mpam_resctrl.c
> > +++ b/drivers/resctrl/mpam_resctrl.c
> > @@ -1018,6 +1018,7 @@ static int mpam_resctrl_control_init(struct mpam_resctrl_res *res)
> >         case RDT_RESOURCE_L3:
> >                 mpam_ctrl->r_ctrl.type = RESCTRL_CTRL_BITMAP;
> >                 mpam_ctrl->r_ctrl.name = RESCTRL_CTRL_NAME_DEF;
> > +               INIT_LIST_HEAD(&mpam_ctrl->r_ctrl.emulated_by);
> >                 INIT_LIST_HEAD_RCU(&mpam_ctrl->r_ctrl.domains);
> >                 __set_bit(RESCTRL_BITMAP_FLAG_SPARSE, mpam_ctrl->r_ctrl.bitmap.flags);
> >                 mpam_ctrl->r_ctrl.bitmap.cbm_len = class->props.cpbm_wd;
> > @@ -1048,6 +1049,7 @@ static int mpam_resctrl_control_init(struct mpam_resctrl_res *res)
> >                 r->ctrl_scope = RESCTRL_L3_CACHE;
> >                 mpam_ctrl->r_ctrl.type = RESCTRL_CTRL_SCALAR;
> >                 mpam_ctrl->r_ctrl.name = RESCTRL_CTRL_NAME_DEF;
> > +               INIT_LIST_HEAD(&mpam_ctrl->r_ctrl.emulated_by);
> >                 INIT_LIST_HEAD_RCU(&mpam_ctrl->r_ctrl.domains);
> > 
> >                 r->bw_throttle_mode = THREAD_THROTTLE_UNDEFINED;
> 
> Thank you for this. Added this and it is now available in branch resctrl/controls_rfc_v2.1

Is same needed for x86? I don't see any initialization of the
"r_ctrl.emulated_by" lists in similar initialization functions.

-Tony