[PATCH v8 15/25] x86/resctrl: Introduce cntr_id in mongroup for assignments

[Babu Moger]

mbm_cntr_assign feature provides an option to the user to assign a counter
to an RMID, event pair and monitor the bandwidth as long as the counter is
assigned. There can be two counters per monitor group, one for MBM total
event and another for MBM local event.

Introduce cntr_id to manage the assignments.

Signed-off-by: Babu Moger <babu.moger@xxxxxxx>
---
v8: Minor commit message update.

v7: Minor comment update for cntr_id.

v6: New patch.
    Separated FS and arch bits.
---
 arch/x86/kernel/cpu/resctrl/internal.h | 7 +++++++
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 6 ++++++
 2 files changed, 13 insertions(+)

diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index de397468b945..58298db9034f 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -62,6 +62,11 @@
 /* Setting bit 0 in L3_QOS_EXT_CFG enables the ABMC feature. */
 #define ABMC_ENABLE_BIT			0
 
+/* Maximum assignable counters per resctrl group */
+#define MAX_CNTRS			2
+
+#define MON_CNTR_UNSET			U32_MAX
+
 /**
  * cpumask_any_housekeeping() - Choose any CPU in @mask, preferring those that
  *			        aren't marked nohz_full
@@ -231,12 +236,14 @@ enum rdtgrp_mode {
  * @parent:			parent rdtgrp
  * @crdtgrp_list:		child rdtgroup node list
  * @rmid:			rmid for this rdtgroup
+ * @cntr_id:			IDs of hardware counters assigned to monitor group
  */
 struct mongroup {
 	struct kernfs_node	*mon_data_kn;
 	struct rdtgroup		*parent;
 	struct list_head	crdtgrp_list;
 	u32			rmid;
+	u32			cntr_id[MAX_CNTRS];
 };
 
 /**
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 610eae64b13a..03b670b95c49 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -3530,6 +3530,9 @@ static int mkdir_rdt_prepare_rmid_alloc(struct rdtgroup *rdtgrp)
 	}
 	rdtgrp->mon.rmid = ret;
 
+	rdtgrp->mon.cntr_id[0] = MON_CNTR_UNSET;
+	rdtgrp->mon.cntr_id[1] = MON_CNTR_UNSET;
+
 	ret = mkdir_mondata_all(rdtgrp->kn, rdtgrp, &rdtgrp->mon.mon_data_kn);
 	if (ret) {
 		rdt_last_cmd_puts("kernfs subdir error\n");
@@ -4084,6 +4087,9 @@ static void __init rdtgroup_setup_default(void)
 	rdtgroup_default.closid = RESCTRL_RESERVED_CLOSID;
 	rdtgroup_default.mon.rmid = RESCTRL_RESERVED_RMID;
 	rdtgroup_default.type = RDTCTRL_GROUP;
+	rdtgroup_default.mon.cntr_id[0] = MON_CNTR_UNSET;
+	rdtgroup_default.mon.cntr_id[1] = MON_CNTR_UNSET;
+
 	INIT_LIST_HEAD(&rdtgroup_default.mon.crdtgrp_list);
 
 	list_add(&rdtgroup_default.rdtgroup_list, &rdt_all_groups);
-- 
2.34.1