x86/resctrl: Add interface to read mbm_local_bytes_config

The event configuration can be viewed by the user by reading the configuration
file /sys/fs/resctrl/info/L3_MON/mbm_local_bytes_config. The event
configuration settings are domain specific and will affect all the CPUs in the
domain.

Following are the types of events supported:

==== ===========================================================
Bits Description
==== ===========================================================
6 Dirty Victims from the QOS domain to all types of memory
5 Reads to slow memory in the non-local NUMA domain
4 Reads to slow memory in the local NUMA domain
3 Non-temporal writes to non-local NUMA domain
2 Non-temporal writes to local NUMA domain
1 Reads to memory in the non-local NUMA domain
0 Reads to memory in the local NUMA domain
==== ===========================================================

By default, the mbm_local_bytes_config is set to 0x15 to count all the local
event types.

For example:

$cat /sys/fs/resctrl/info/L3_MON/mbm_local_bytes_config
0=0x15;1=0x15;2=0x15;3=0x15

In this case, the event mbm_local_bytes is configured with 0x15 on
domains 0 to 3.

Signed-off-by: Babu Moger <[e-mail]>
Signed-off-by: Borislav Petkov (AMD) <[e-mail]>
Reviewed-by: Reinette Chatre <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]

arch/x86/kernel/cpu/resctrl/monitor.c

···
 			mbm_total_event.configurable = true;
 			mbm_config_rftype_init("mbm_total_bytes_config");
 		}
-		if (rdt_cpu_has(X86_FEATURE_CQM_MBM_LOCAL))
+		if (rdt_cpu_has(X86_FEATURE_CQM_MBM_LOCAL)) {
 			mbm_local_event.configurable = true;
+			mbm_config_rftype_init("mbm_local_bytes_config");
+		}
 	}
 
 	l3_mon_evt_init(r);

arch/x86/kernel/cpu/resctrl/rdtgroup.c

···
 	return 0;
 }
 
+static int mbm_local_bytes_config_show(struct kernfs_open_file *of,
+				       struct seq_file *seq, void *v)
+{
+	struct rdt_resource *r = of->kn->parent->priv;
+
+	mbm_config_show(seq, r, QOS_L3_MBM_LOCAL_EVENT_ID);
+
+	return 0;
+}
+
 /* rdtgroup information files for one cache resource. */
 static struct rftype res_common_files[] = {
 	{
···
 		.mode		= 0444,
 		.kf_ops		= &rdtgroup_kf_single_ops,
 		.seq_show	= mbm_total_bytes_config_show,
+	},
+	{
+		.name		= "mbm_local_bytes_config",
+		.mode		= 0444,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= mbm_local_bytes_config_show,
 	},
 	{
 		.name		= "cpus",