On Wed, Oct 25, 2023 at 02:46:53PM +0200, Peter Newman wrote:
> Hi Tony,
>
> On Tue, Oct 24, 2023 at 8:16 PM Tony Luck <tony.luck@xxxxxxxxx> wrote:
> > --- a/arch/x86/kernel/cpu/resctrl/monitor.c
> > +++ b/arch/x86/kernel/cpu/resctrl/monitor.c
> > @@ -418,6 +418,14 @@ static int __mon_event_count(u32 rmid, struct rmid_read *rr)
> > return 0;
> > }
> >
> > +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?"
I could add a s/w defined "event" to the enum resctrl_event_id and
extend get_mbm_state() like this:
static struct mbm_state *get_mbm_state(struct rdt_domain *d, u32 rmid,
enum resctrl_event_id evtid)
{
switch (evtid) {
case QOS_L3_MBM_TOTAL_EVENT_ID:
return &d->mbm_total[rmid];
case QOS_L3_MBM_LOCAL_EVENT_ID:
return &d->mbm_local[rmid];
+ case QOS_L3_MBM_LOCAL_OR_TOTAL_EVENT_ID:
+ if (is_mbm_local_enabled())
+ return &d->mbm_local[rmid];
+ if (is_mbm_total_enabled())
+ return &d->mbm_total[rmid];
+ fallthrough;
default:
return NULL;
}
}
Is this the direction you are thinking of?
Callers then look like:
static void mbm_bw_count(u32 rmid, struct rmid_read *rr)
{
struct mbm_state *m = get_mbm_state(rr->d, rmid, QOS_L3_MBM_LOCAL_OR_TOTAL_EVENT_ID);
u64 cur_bw, bytes, cur_bytes;
similar for the other three places where this is needed.
Any suggestions on how "QOS_L3_MBM_LOCAL_OR_TOTAL_EVENT_ID" could be
abbreviated, or just have some different, but descriptive, name?
-Tony
