RE: [PATCH v9 07/13] x86/resctrl: Introduce data structure to support monitor configuration

[Moger, Babu]

[AMD Official Use Only - General]

Hi Reinette,

> -----Original Message-----
> From: Reinette Chatre <reinette.chatre@xxxxxxxxx>
> Sent: Thursday, December 15, 2022 11:19 AM
> To: Moger, Babu <Babu.Moger@xxxxxxx>; corbet@xxxxxxx;
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> Subject: Re: [PATCH v9 07/13] x86/resctrl: Introduce data structure to support
> monitor configuration
> 
> Hi Babu,
> 
> I do not see a new data structure introduced. Perhaps subject could just be:
> x86/resctrl: Support monitor configuration

Sure
> 
> On 12/1/2022 7:36 AM, Babu Moger wrote:
> > Add a new field in mon_evt to support Bandwidth Monitoring Event
> 
> "mon_evt" -> "struct mon_evt"
Ok
> 
> > Configuration(BMEC) and also update the "mon_features" display.
> >
> > The resctrl file "mon_features" will display the supported events and
> > files that can be used to configure those events if monitor
> > configuration is supported.
> >
> > Before the change.
> > 	$cat /sys/fs/resctrl/info/L3_MON/mon_features
> > 	llc_occupancy
> > 	mbm_total_bytes
> > 	mbm_local_bytes
> >
> > After the change when BMEC is supported.
> > 	$cat /sys/fs/resctrl/info/L3_MON/mon_features
> > 	llc_occupancy
> > 	mbm_total_bytes
> > 	mbm_total_bytes_config
> > 	mbm_local_bytes
> > 	mbm_local_bytes_config
> >
> > Signed-off-by: Babu Moger <babu.moger@xxxxxxx>
> > ---
> >  arch/x86/kernel/cpu/resctrl/internal.h |    2 ++
> >  arch/x86/kernel/cpu/resctrl/monitor.c  |    7 +++++++
> >  arch/x86/kernel/cpu/resctrl/rdtgroup.c |    5 ++++-
> >  3 files changed, 13 insertions(+), 1 deletion(-)
> >
> > diff --git a/arch/x86/kernel/cpu/resctrl/internal.h
> > b/arch/x86/kernel/cpu/resctrl/internal.h
> > index 7bbfc10094b6..b36750334deb 100644
> > --- a/arch/x86/kernel/cpu/resctrl/internal.h
> > +++ b/arch/x86/kernel/cpu/resctrl/internal.h
> > @@ -52,11 +52,13 @@ DECLARE_STATIC_KEY_FALSE(rdt_mon_enable_key);
> >   * struct mon_evt - Entry in the event list of a resource
> >   * @evtid:		event id
> >   * @name:		name of the event
> > + * @configurable:	true if the event is configurable
> >   * @list:		entry in &rdt_resource->evt_list
> >   */
> >  struct mon_evt {
> >  	enum resctrl_event_id	evtid;
> >  	char			*name;
> > +	bool			configurable;
> >  	struct list_head	list;
> >  };
> >
> > diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c
> > b/arch/x86/kernel/cpu/resctrl/monitor.c
> > index e33e8d8bd796..b39e0eca1879 100644
> > --- a/arch/x86/kernel/cpu/resctrl/monitor.c
> > +++ b/arch/x86/kernel/cpu/resctrl/monitor.c
> > @@ -783,6 +783,13 @@ int __init rdt_get_mon_l3_config(struct
> rdt_resource *r)
> >  	if (ret)
> >  		return ret;
> >
> > +	if (rdt_cpu_has(X86_FEATURE_BMEC)) {
> > +		if (rdt_cpu_has(X86_FEATURE_CQM_MBM_TOTAL))
> > +			mbm_total_event.configurable = true;
> > +		if (rdt_cpu_has(X86_FEATURE_CQM_MBM_LOCAL))
> > +			mbm_local_event.configurable = true;
> > +	}
> > +
> >  	l3_mon_evt_init(r);
> >
> >  	r->mon_capable = true;
> > diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> > b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> > index 8a3dafc0dbf7..8342feb54a7f 100644
> > --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> > +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> > @@ -1001,8 +1001,11 @@ static int rdt_mon_features_show(struct
> kernfs_open_file *of,
> >  	struct rdt_resource *r = of->kn->parent->priv;
> >  	struct mon_evt *mevt;
> >
> > -	list_for_each_entry(mevt, &r->evt_list, list)
> > +	list_for_each_entry(mevt, &r->evt_list, list) {
> >  		seq_printf(seq, "%s\n", mevt->name);
> > +		if (mevt->configurable)
> > +			seq_printf(seq, "%s_config\n", mevt->name);
> > +	}
> >
> >  	return 0;
> >  }
> >
> >
> 
> With subject and changelog changes:
> 
> Reviewed-by: Reinette Chatre <reinette.chatre@xxxxxxxxx>

Thanks
Babu
> 
> Reinette