[PATCH 6.18.y 1/6] fs/resctrl: Split L3 dependent parts out of __mon_event_count()

[Sasha Levin <sashal@kernel.org>]

From: Tony Luck <tony.luck@intel.com>

[ Upstream commit ad5c2ff75e0c53d2588dfc10eb87458e759b6bbe ]

Carve out the L3 resource specific event reading code into a separate helper
to support reading event data from a new monitoring resource.

Suggested-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Link: https://lore.kernel.org/20251217172121.12030-1-tony.luck@intel.com
Stable-dep-of: 52fce648607e ("fs/resctrl: Fix use-after-free during unmount")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/resctrl/monitor.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/fs/resctrl/monitor.c b/fs/resctrl/monitor.c
index 7012a75814ac36..cdd5070d9ec71d 100644
--- a/fs/resctrl/monitor.c
+++ b/fs/resctrl/monitor.c
@@ -418,7 +418,7 @@ static void mbm_cntr_free(struct rdt_mon_domain *d, int cntr_id)
 	memset(&d->cntr_cfg[cntr_id], 0, sizeof(*d->cntr_cfg));
 }
 
-static int __mon_event_count(struct rdtgroup *rdtgrp, struct rmid_read *rr)
+static int __l3_mon_event_count(struct rdtgroup *rdtgrp, struct rmid_read *rr)
 {
 	int cpu = smp_processor_id();
 	u32 closid = rdtgrp->closid;
@@ -499,6 +499,17 @@ static int __mon_event_count(struct rdtgroup *rdtgrp, struct rmid_read *rr)
 	return ret;
 }
 
+static int __mon_event_count(struct rdtgroup *rdtgrp, struct rmid_read *rr)
+{
+	switch (rr->r->rid) {
+	case RDT_RESOURCE_L3:
+		return __l3_mon_event_count(rdtgrp, rr);
+	default:
+		rr->err = -EINVAL;
+		return -EINVAL;
+	}
+}
+
 /*
  * mbm_bw_count() - Update bw count from values previously read by
  *		    __mon_event_count().
-- 
2.53.0