[PATCH v4 08/13] x86/resctrl : Introduce data structure to support monitor configuration

[Babu Moger]

Add couple of fields in mon_evt to support Bandwidth Monitoring Event
Configuratio (BMEC) and also update the "mon_features".

The sysfs file "mon_features" will display the monitor configuration if
supported.

Before the change.
	$cat /sys/fs/resctrl/info/L3_MON/mon_features
	llc_occupancy
	mbm_total_bytes
	mbm_local_bytes

After the change if BMEC is supported.
	$cat /sys/fs/resctrl/info/L3_MON/mon_features
	llc_occupancy
	mbm_total_bytes
	mbm_total_config
	mbm_local_bytes
	mbm_local_config

Signed-off-by: Babu Moger <babu.moger@xxxxxxx>
---
 arch/x86/kernel/cpu/resctrl/core.c     |    3 ++-
 arch/x86/kernel/cpu/resctrl/internal.h |    6 +++++-
 arch/x86/kernel/cpu/resctrl/monitor.c  |    9 ++++++++-
 arch/x86/kernel/cpu/resctrl/rdtgroup.c |    5 ++++-
 4 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 56c96607259c..513e6a00f58e 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -849,6 +849,7 @@ static __init bool get_rdt_alloc_resources(void)
 static __init bool get_rdt_mon_resources(void)
 {
 	struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
+	bool mon_configurable = rdt_cpu_has(X86_FEATURE_BMEC);
 
 	if (rdt_cpu_has(X86_FEATURE_CQM_OCCUP_LLC))
 		rdt_mon_features |= (1 << QOS_L3_OCCUP_EVENT_ID);
@@ -860,7 +861,7 @@ static __init bool get_rdt_mon_resources(void)
 	if (!rdt_mon_features)
 		return false;
 
-	return !rdt_get_mon_l3_config(r);
+	return !rdt_get_mon_l3_config(r, mon_configurable);
 }
 
 static __init void __check_quirks_intel(void)
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index c049a274383c..45923eb4022f 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -72,11 +72,15 @@ 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
+ * @config_name:	sysfs file name of the event if configurable
  * @list:		entry in &rdt_resource->evt_list
  */
 struct mon_evt {
 	u32			evtid;
 	char			*name;
+	bool 			configurable;
+	char			*config_name;
 	struct list_head	list;
 };
 
@@ -529,7 +533,7 @@ int closids_supported(void);
 void closid_free(int closid);
 int alloc_rmid(void);
 void free_rmid(u32 rmid);
-int rdt_get_mon_l3_config(struct rdt_resource *r);
+int rdt_get_mon_l3_config(struct rdt_resource *r, bool configurable);
 void mon_event_count(void *info);
 int rdtgroup_mondata_show(struct seq_file *m, void *arg);
 void rmdir_mondata_subdir_allrdtgrp(struct rdt_resource *r,
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index eaf25a234ff5..dc97aa7a3b3d 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -656,11 +656,13 @@ static struct mon_evt llc_occupancy_event = {
 static struct mon_evt mbm_total_event = {
 	.name		= "mbm_total_bytes",
 	.evtid		= QOS_L3_MBM_TOTAL_EVENT_ID,
+	.config_name	= "mbm_total_config",
 };
 
 static struct mon_evt mbm_local_event = {
 	.name		= "mbm_local_bytes",
 	.evtid		= QOS_L3_MBM_LOCAL_EVENT_ID,
+	.config_name	= "mbm_local_config",
 };
 
 /*
@@ -682,7 +684,7 @@ static void l3_mon_evt_init(struct rdt_resource *r)
 		list_add_tail(&mbm_local_event.list, &r->evt_list);
 }
 
-int rdt_get_mon_l3_config(struct rdt_resource *r)
+int rdt_get_mon_l3_config(struct rdt_resource *r, bool configurable)
 {
 	unsigned int mbm_offset = boot_cpu_data.x86_cache_mbm_width_offset;
 	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
@@ -714,6 +716,11 @@ int rdt_get_mon_l3_config(struct rdt_resource *r)
 	if (ret)
 		return ret;
 
+	if (configurable) {
+		mbm_total_event.configurable = true;
+		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 fc5286067201..f55a693fa958 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\n", mevt->config_name);
+	}
 
 	return 0;
 }