x86/resctrl: Introduce interface to list monitor states of all the groups

ANBZ: #9790

cherry-picked from https://lore.kernel.org/all/cover.1722981659.git.babu.moger@amd.com/

Provide the interface to list the monitor states of all the resctrl
groups in ABMC mode.

Example:
$cat /sys/fs/resctrl/info/L3_MON/mbm_control

List follows the following format:

"<CTRL_MON group>/<MON group>/<domain_id>=<flags>"

Format for specific type of groups:

- Default CTRL_MON group:
  "//<domain_id>=<flags>"

- Non-default CTRL_MON group:
  "<CTRL_MON group>//<domain_id>=<flags>"

- Child MON group of default CTRL_MON group:
  "/<MON group>/<domain_id>=<flags>"

- Child MON group of non-default CTRL_MON group:
  "<CTRL_MON group>/<MON group>/<domain_id>=<flags>"

Flags can be one of the following:
t  MBM total event is enabled
l  MBM local event is enabled
tl Both total and local MBM events are enabled
_  None of the MBM events are enabled

Signed-off-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Kun(llfl) <llfl@linux.alibaba.com>
Reviewed-by: Artie Ding <artie.ding@linux.alibaba.com>
Link: https://gitee.com/anolis/cloud-kernel/pulls/3731

Documentation/x86/resctrl.rst

@@ -317,6 +317,50 @@ with the following files:
 	the counter is not assigned to the event when read. Users need to assign a
 	counter manually to read the events.
 
+"mbm_control":
+	Reports the resctrl group and monitor status of each group.
+
+	List follows the following format:
+		"<CTRL_MON group>/<MON group>/<domain_id>=<flags>"
+
+	Format for specific type of groups:
+
+	* Default CTRL_MON group:
+		"//<domain_id>=<flags>"
+
+	* Non-default CTRL_MON group:
+		"<CTRL_MON group>//<domain_id>=<flags>"
+
+	* Child MON group of default CTRL_MON group:
+		"/<MON group>/<domain_id>=<flags>"
+
+	* Child MON group of non-default CTRL_MON group:
+		"<CTRL_MON group>/<MON group>/<domain_id>=<flags>"
+
+	Flags can be one of the following:
+	::
+
+	 t  MBM total event is enabled.
+	 l  MBM local event is enabled.
+	 tl Both total and local MBM events are enabled.
+	 _  None of the MBM events are enabled.
+
+	Examples:
+	::
+
+	 # mkdir /sys/fs/resctrl/mon_groups/child_default_mon_grp
+	 # mkdir /sys/fs/resctrl/non_default_ctrl_mon_grp
+	 # mkdir /sys/fs/resctrl/non_default_ctrl_mon_grp/mon_groups/child_non_default_mon_grp
+
+	 # cat /sys/fs/resctrl/info/L3_MON/mbm_control
+	 non_default_ctrl_mon_grp//0=tl;1=tl;
+	 non_default_ctrl_mon_grp/child_non_default_mon_grp/0=tl;1=tl;
+	 //0=tl;1=tl;
+	 /child_default_mon_grp/0=tl;1=tl;
+
+	 There are four resctrl groups. All the groups have total and local MBM events
+	 enabled on domain 0 and 1.
+
 "max_threshold_occupancy":
 		Read/write file provides the largest value (in
 		bytes) at which a previously used LLC_occupancy

arch/x86/include/asm/resctrl.h

@@ -231,6 +231,7 @@ bool resctrl_arch_get_abmc_enabled(void);
 
 int resctrl_arch_mbm_cntr_assign_enable(void);
 void resctrl_arch_mbm_cntr_assign_disable(void);
+bool resctrl_arch_get_mbm_cntr_assign_enable(void);
 
 void resctrl_arch_event_config_set(void *info);
 u32 resctrl_arch_event_config_get(void *dom,

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

@@ -237,6 +237,14 @@ void resctrl_arch_mbm_cntr_assign_disable(void)
 	}
 }
 
+bool resctrl_arch_get_mbm_cntr_assign_enable(void)
+{
+	struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
+	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
+
+	return hw_res->mbm_cntr_assign_enabled;
+}
+
 static void rdtgroup_abmc_cfg(void *info)
 {
 	u64 *msrval = info;

fs/resctrl/monitor.c

@@ -748,8 +748,10 @@ static void l3_mon_evt_init(struct rdt_resource *r)
 					 RF_MON_INFO | RFTYPE_RES_CACHE);
 	}
 
-	if (resctrl_arch_get_abmc_enabled())
+	if (resctrl_arch_get_abmc_enabled()) {
 		resctrl_file_fflags_init("num_mbm_cntrs", RF_MON_INFO);
+		resctrl_file_fflags_init("mbm_control", RF_MON_INFO);
+	}
 
 	if (resctrl_arch_is_llc_occupancy_enabled())
 		list_add_tail(&llc_occupancy_event.list, &r->mon.evt_list);

fs/resctrl/rdtgroup.c

@@ -887,6 +887,74 @@ static int rdtgroup_num_mbm_cntrs_show(struct kernfs_open_file *of,
 	return 0;
 }
 
+static char *rdtgroup_mon_state_to_str(struct rdtgroup *rdtgrp,
+				       struct rdt_domain *d, char *str)
+{
+	char *tmp = str;
+	int index;
+
+	/*
+	 * Query the monitor state for the domain.
+	 * Index 0 for evtid == QOS_L3_MBM_TOTAL_EVENT_ID
+	 * Index 1 for evtid == QOS_L3_MBM_LOCAL_EVENT_ID
+	 */
+	index = mon_event_config_index_get(QOS_L3_MBM_TOTAL_EVENT_ID);
+	if (rdtgrp->mon.cntr_id[index] != MON_CNTR_UNSET &&
+	    test_bit(rdtgrp->mon.cntr_id[index], d->mbm_cntr_map))
+		*tmp++ = 't';
+
+	index = mon_event_config_index_get(QOS_L3_MBM_LOCAL_EVENT_ID);
+	if (rdtgrp->mon.cntr_id[index] != MON_CNTR_UNSET &&
+	    test_bit(rdtgrp->mon.cntr_id[index], d->mbm_cntr_map))
+		*tmp++ = 'l';
+
+	if (tmp == str)
+		*tmp++ = '_';
+
+	*tmp = '\0';
+	return str;
+}
+
+static int rdtgroup_mbm_control_show(struct kernfs_open_file *of,
+				     struct seq_file *s, void *v)
+{
+	struct rdt_resource *r = of->kn->parent->priv;
+	struct rdt_domain *dom;
+	struct rdtgroup *rdtg;
+	char str[10];
+
+	if (!resctrl_arch_get_mbm_cntr_assign_enable()) {
+		rdt_last_cmd_puts("ABMC feature is not enabled\n");
+		return -EINVAL;
+	}
+
+	mutex_lock(&rdtgroup_mutex);
+
+	list_for_each_entry(rdtg, &rdt_all_groups, rdtgroup_list) {
+		struct rdtgroup *crg;
+
+		seq_printf(s, "%s//", rdtg->kn->name);
+
+		list_for_each_entry(dom, &r->domains, list)
+			seq_printf(s, "%d=%s;", dom->id,
+				   rdtgroup_mon_state_to_str(rdtg, dom, str));
+		seq_putc(s, '\n');
+
+		list_for_each_entry(crg, &rdtg->mon.crdtgrp_list,
+				    mon.crdtgrp_list) {
+			seq_printf(s, "%s/%s/", rdtg->kn->name, crg->kn->name);
+
+			list_for_each_entry(dom, &r->domains, list)
+				seq_printf(s, "%d=%s;", dom->id,
+					   rdtgroup_mon_state_to_str(crg, dom, str));
+			seq_putc(s, '\n');
+		}
+	}
+
+	mutex_unlock(&rdtgroup_mutex);
+	return 0;
+}
+
 #ifdef CONFIG_PROC_CPU_RESCTRL
 
 /*
@@ -2066,6 +2134,12 @@ static struct rftype res_common_files[] = {
 		.kf_ops		= &rdtgroup_kf_single_ops,
 		.seq_show	= rdtgroup_num_mbm_cntrs_show,
 	},
+	{
+		.name		= "mbm_control",
+		.mode		= 0444,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= rdtgroup_mbm_control_show,
+	},
 	{
 		.name		= "cpus_list",
 		.mode		= 0644,

include/linux/arm_mpam.h

@@ -126,6 +126,11 @@ static inline int resctrl_arch_mbm_cntr_assign_enable(void)
 
 static inline void resctrl_arch_mbm_cntr_assign_disable(void) { }
 
+static inline bool resctrl_arch_get_mbm_cntr_assign_enable(void)
+{
+	return false;
+}
+
 static inline void resctrl_arch_event_config_set(void *info) { }
 static inline u32 resctrl_arch_event_config_get(void *dom,
 						enum resctrl_event_id eventid)