3 files changed, 68 insertions, 7 deletions

diff --git a/arch/x86/kernel/cpu/resctrl/intel_aet.c b/arch/x86/kernel/cpu/resctrl/intel_aet.c
index 8e042b530c91..7d0bd7b070a7 100644
--- a/arch/x86/kernel/cpu/resctrl/intel_aet.c
+++ b/arch/x86/kernel/cpu/resctrl/intel_aet.c
@@ -16,9 +16,11 @@
 #include <linux/init.h>
 #include <linux/intel_pmt_features.h>
 #include <linux/intel_vsec.h>
+#include <linux/printk.h>
 #include <linux/resctrl.h>
 #include <linux/resctrl_types.h>
 #include <linux/stddef.h>
+#include <linux/topology.h>
 #include <linux/types.h>
 
 #include "internal.h"
@@ -110,12 +112,69 @@ static struct event_group *known_event_groups[] = {
 	     _peg < &known_event_groups[ARRAY_SIZE(known_event_groups)];	\
 	     _peg++)
 
-/* Stub for now */
-static bool enable_events(struct event_group *e, struct pmt_feature_group *p)
+static bool skip_telem_region(struct telemetry_region *tr, struct event_group *e)
 {
+	if (tr->guid != e->guid)
+		return true;
+	if (tr->plat_info.package_id >= topology_max_packages()) {
+		pr_warn("Bad package %u in guid 0x%x\n", tr->plat_info.package_id,
+			tr->guid);
+		return true;
+	}
+	if (tr->size != e->mmio_size) {
+		pr_warn("MMIO space wrong size (%zu bytes) for guid 0x%x. Expected %zu bytes.\n",
+			tr->size, e->guid, e->mmio_size);
+		return true;
+	}
+
 	return false;
 }
 
+static bool group_has_usable_regions(struct event_group *e, struct pmt_feature_group *p)
+{
+	bool usable_regions = false;
+
+	for (int i = 0; i < p->count; i++) {
+		if (skip_telem_region(&p->regions[i], e)) {
+			/*
+			 * Clear the address field of regions that did not pass the checks in
+			 * skip_telem_region() so they will not be used by intel_aet_read_event().
+			 * This is safe to do because intel_pmt_get_regions_by_feature() allocates
+			 * a new pmt_feature_group structure to return to each caller and only makes
+			 * use of the pmt_feature_group::kref field when intel_pmt_put_feature_group()
+			 * returns the structure.
+			 */
+			p->regions[i].addr = NULL;
+
+			continue;
+		}
+		usable_regions = true;
+	}
+
+	return usable_regions;
+}
+
+static bool enable_events(struct event_group *e, struct pmt_feature_group *p)
+{
+	struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_PERF_PKG].r_resctrl;
+	int skipped_events = 0;
+
+	if (!group_has_usable_regions(e, p))
+		return false;
+
+	for (int j = 0; j < e->num_events; j++) {
+		if (!resctrl_enable_mon_event(e->evts[j].id, true,
+					      e->evts[j].bin_bits, &e->evts[j]))
+			skipped_events++;
+	}
+	if (e->num_events == skipped_events) {
+		pr_info("No events enabled in %s %s:0x%x\n", r->name, e->pfname, e->guid);
+		return false;
+	}
+
+	return true;
+}
+
 static enum pmt_feature_id lookup_pfid(const char *pfname)
 {
 	if (!strcmp(pfname, "energy"))
diff --git a/fs/resctrl/monitor.c b/fs/resctrl/monitor.c
index af43a33ce4cb..9af08b673e39 100644
--- a/fs/resctrl/monitor.c
+++ b/fs/resctrl/monitor.c
@@ -997,25 +997,27 @@ struct mon_evt mon_event_all[QOS_NUM_EVENTS] = {
 	MON_EVENT(PMT_EVENT_UOPS_RETIRED,		"uops_retired",		RDT_RESOURCE_PERF_PKG,	false),
 };
 
-void resctrl_enable_mon_event(enum resctrl_event_id eventid, bool any_cpu,
+bool resctrl_enable_mon_event(enum resctrl_event_id eventid, bool any_cpu,
 			      unsigned int binary_bits, void *arch_priv)
 {
 	if (WARN_ON_ONCE(eventid < QOS_FIRST_EVENT || eventid >= QOS_NUM_EVENTS ||
 			 binary_bits > MAX_BINARY_BITS))
-		return;
+		return false;
 	if (mon_event_all[eventid].enabled) {
 		pr_warn("Duplicate enable for event %d\n", eventid);
-		return;
+		return false;
 	}
 	if (binary_bits && !mon_event_all[eventid].is_floating_point) {
 		pr_warn("Event %d may not be floating point\n", eventid);
-		return;
+		return false;
 	}
 
 	mon_event_all[eventid].any_cpu = any_cpu;
 	mon_event_all[eventid].binary_bits = binary_bits;
 	mon_event_all[eventid].arch_priv = arch_priv;
 	mon_event_all[eventid].enabled = true;
+
+	return true;
 }
 
 bool resctrl_is_mon_event_enabled(enum resctrl_event_id eventid)
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 2c64a43a36db..451eb45e44f8 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -414,7 +414,7 @@ u32 resctrl_arch_get_num_closid(struct rdt_resource *r);
 u32 resctrl_arch_system_num_rmid_idx(void);
 int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid);
 
-void resctrl_enable_mon_event(enum resctrl_event_id eventid, bool any_cpu,
+bool resctrl_enable_mon_event(enum resctrl_event_id eventid, bool any_cpu,
 			      unsigned int binary_bits, void *arch_priv);
 
 bool resctrl_is_mon_event_enabled(enum resctrl_event_id eventid);