[RFC PATCH v1 3/4] arm_mpam: resctrl: Add resctrl_arch_config_cntr() for ABMC use

Ben Horgan ben.horgan at arm.com
Wed Feb 25 12:54:35 PST 2026


From: James Morse <james.morse at arm.com>

ABMC has a helper resctrl_arch_config_cntr() for changing the mapping
between 'cntr_id' and a CLOSID/RMID pair.

Add the helper.

For MPAM this is done by updating the mon->mbwu_idx_to_mon[] array, and as
usual CDP means it needs doing in three different ways.

Reviewed-by: Jonathan Cameron <jonathan.cameron at huawei.com>
Signed-off-by: James Morse <james.morse at arm.com>
Signed-off-by: Ben Horgan <ben.horgan at arm.com>
---
 drivers/resctrl/mpam_resctrl.c | 43 +++++++++++++++++++++++++++++-----
 1 file changed, 37 insertions(+), 6 deletions(-)

diff --git a/drivers/resctrl/mpam_resctrl.c b/drivers/resctrl/mpam_resctrl.c
index 58fd3ee10fd2..18528210ba46 100644
--- a/drivers/resctrl/mpam_resctrl.c
+++ b/drivers/resctrl/mpam_resctrl.c
@@ -143,12 +143,6 @@ void resctrl_arch_reset_cntr(struct rdt_resource *r, struct rdt_l3_mon_domain *d
 {
 }
 
-void resctrl_arch_config_cntr(struct rdt_resource *r, struct rdt_l3_mon_domain *d,
-			      enum resctrl_event_id evtid, u32 rmid, u32 closid,
-			      u32 cntr_id, bool assign)
-{
-}
-
 int resctrl_arch_cntr_read(struct rdt_resource *r, struct rdt_l3_mon_domain *d,
 			   u32 unused, u32 rmid, int cntr_id,
 			   enum resctrl_event_id eventid, u64 *val)
@@ -1180,6 +1174,43 @@ static void mpam_resctrl_pick_counters(void)
 	}
 }
 
+static void __config_cntr(struct mpam_resctrl_mon *mon, u32 cntr_id,
+			  enum resctrl_conf_type cdp_type, u32 closid, u32 rmid,
+			  bool assign)
+{
+	u32 mbwu_idx, mon_idx = resctrl_get_config_index(cntr_id, cdp_type);
+
+	closid = resctrl_get_config_index(closid, cdp_type);
+	mbwu_idx = resctrl_arch_rmid_idx_encode(closid, rmid);
+	WARN_ON_ONCE(mon_idx > l3_num_allocated_mbwu);
+
+	if (assign)
+		mon->mbwu_idx_to_mon[mbwu_idx] = mon->assigned_counters[mon_idx];
+	else
+		mon->mbwu_idx_to_mon[mbwu_idx] = -1;
+}
+
+void resctrl_arch_config_cntr(struct rdt_resource *r, struct rdt_l3_mon_domain *d,
+			      enum resctrl_event_id evtid, u32 rmid, u32 closid,
+			      u32 cntr_id, bool assign)
+{
+	struct mpam_resctrl_mon *mon = &mpam_resctrl_counters[evtid];
+
+	if (!mon->mbwu_idx_to_mon || !mon->assigned_counters) {
+		pr_debug("monitor arrays not allocated\n");
+		return;
+	}
+
+	if (cdp_enabled) {
+		__config_cntr(mon, cntr_id, CDP_CODE, closid, rmid, assign);
+		__config_cntr(mon, cntr_id, CDP_DATA, closid, rmid, assign);
+	} else {
+		__config_cntr(mon, cntr_id, CDP_NONE, closid, rmid, assign);
+	}
+
+	resctrl_arch_reset_rmid(r, d, closid, rmid, evtid);
+}
+
 static int mpam_resctrl_control_init(struct mpam_resctrl_res *res)
 {
 	struct mpam_class *class = res->class;
-- 
2.43.0




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