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

From: Reinette Chatre
Date: Thu Dec 15 2022 - 12:19:51 EST


Hi Babu,

I do not see a new data structure introduced. Perhaps subject
could just be:
x86/resctrl: Support monitor configuration

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"

> 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>

Reinette