[PATCH 05/10] x86/resctrl: Add parent/child information to rdt_resource and rdt_domain

[Tony Luck]

The L3 resource is a "parent" to the SUBL3 resource in that each of the
domains in L3 is subdivided into two or more SUBL3 domains.

Add parent/child pointers to the rdt_resource structure and a
parent domain id number to the rdt_domain structure.

Signed-off-by: Tony Luck <tony.luck@xxxxxxxxx>
---
 include/linux/resctrl.h                |  6 ++++++
 arch/x86/kernel/cpu/resctrl/core.c     | 12 ++++++++++++
 arch/x86/kernel/cpu/resctrl/rdtgroup.c |  4 +++-
 3 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index dea79f6a8122..b7ade7627e08 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -70,6 +70,7 @@ struct resctrl_staged_config {
  * @cqm_limbo:		worker to periodically read CQM h/w counters
  * @mbm_work_cpu:	worker CPU for MBM h/w counters
  * @cqm_work_cpu:	worker CPU for CQM h/w counters
+ * @parent:		parent domain number in parent resource
  * @plr:		pseudo-locked region (if any) associated with domain
  * @staged_config:	parsed configuration to be applied
  * @mbps_val:		When mba_sc is enabled, this holds the array of user
@@ -87,6 +88,7 @@ struct rdt_domain {
 	struct delayed_work		cqm_limbo;
 	int				mbm_work_cpu;
 	int				cqm_work_cpu;
+	int				parent;
 	struct pseudo_lock_region	*plr;
 	struct resctrl_staged_config	staged_config[CDP_NUM_TYPES];
 	u32				*mbps_val;
@@ -173,6 +175,8 @@ enum resctrl_scope {
  * @format_str:		Per resource format string to show domain value
  * @parse_ctrlval:	Per resource function pointer to parse control values
  * @evt_list:		List of monitoring events
+ * @parent:		Parent of this resource
+ * @child:		Child of this resource
  * @fflags:		flags to choose base and info files
  * @cdp_capable:	Is the CDP feature available on this resource
  */
@@ -194,6 +198,8 @@ struct rdt_resource {
 						 struct resctrl_schema *s,
 						 struct rdt_domain *d);
 	struct list_head	evt_list;
+	struct rdt_resource	*parent;
+	struct rdt_resource	*child;
 	unsigned long		fflags;
 	bool			cdp_capable;
 };
diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 2fa04375da8c..1f5d7ee0096e 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -552,6 +552,18 @@ static void domain_add_cpu(int cpu, struct rdt_resource *r)
 	d->id = id;
 	cpumask_set_cpu(cpu, &d->cpu_mask);
 
+	if (r->parent) {
+		struct rdt_domain *pd;
+
+		list_for_each_entry(pd, &r->parent->domains, list)
+			if (cpumask_test_cpu(cpu, &pd->cpu_mask))
+				goto found;
+		WARN_ON_ONCE(1);
+		return;
+found:
+		d->parent = pd->id;
+	}
+
 	rdt_domain_reconfigure_cdp(r);
 
 	if (r->alloc_capable && domain_setup_ctrlval(r, d)) {
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index a2ebd7e051bb..f2af58a791a4 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -1107,9 +1107,11 @@ static int rdt_mon_features_show(struct kernfs_open_file *of,
 				 struct seq_file *seq, void *v)
 {
 	struct rdt_resource *r = of->kn->parent->priv;
+	struct list_head *evt_list;
 	struct mon_evt *mevt;
 
-	list_for_each_entry(mevt, &r->evt_list, list) {
+	evt_list = r->child ? &r->child->evt_list : &r->evt_list;
+	list_for_each_entry(mevt, evt_list, list) {
 		seq_printf(seq, "%s\n", mevt->name);
 		if (mevt->configurable)
 			seq_printf(seq, "%s_config\n", mevt->name);
-- 
2.44.0