[PATCH v3 2/8] x86/resctrl: Remove hard code of RDT_RESOURCE_L3 in monitor.c

From: Tony Luck
Date: Thu Jul 13 2023 - 12:32:38 EST


Scope of monitoring may be scoped at L3 cache granularity (legacy) or
at the node level (systems with Sub NUMA Cluster enabled).

Save the struct rdt_resource pointer that was used to initialize
the monitor sections of code and use that value instead of the
hard-coded RDT_RESOURCE_L3.

No functional change.

Signed-off-by: Tony Luck <tony.luck@xxxxxxxxx>
Reviewed-by: Peter Newman <peternewman@xxxxxxxxxx>
---
arch/x86/kernel/cpu/resctrl/monitor.c | 18 +++++++++++-------
1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index ded1fc7cb7cb..9be6ffdd01ae 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -30,6 +30,8 @@ struct rmid_entry {
struct list_head list;
};

+static struct rdt_resource *mon_resource;
+
/**
* @rmid_free_lru A least recently used list of free RMIDs
* These RMIDs are guaranteed to have an occupancy less than the
@@ -268,7 +270,7 @@ int resctrl_arch_rmid_read(struct rdt_resource *r, struct rdt_domain *d,
*/
void __check_limbo(struct rdt_domain *d, bool force_free)
{
- struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
+ struct rdt_resource *r = mon_resource;
struct rmid_entry *entry;
u32 crmid = 1, nrmid;
bool rmid_dirty;
@@ -333,7 +335,7 @@ int alloc_rmid(void)

static void add_rmid_to_limbo(struct rmid_entry *entry)
{
- struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
+ struct rdt_resource *r = mon_resource;
struct rdt_domain *d;
int cpu, err;
u64 val = 0;
@@ -645,7 +647,7 @@ void cqm_handle_limbo(struct work_struct *work)

mutex_lock(&rdtgroup_mutex);

- r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
+ r = mon_resource;
d = container_of(work, struct rdt_domain, cqm_limbo.work);

__check_limbo(d, false);
@@ -681,7 +683,7 @@ void mbm_handle_overflow(struct work_struct *work)
if (!static_branch_likely(&rdt_mon_enable_key))
goto out_unlock;

- r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
+ r = mon_resource;
d = container_of(work, struct rdt_domain, mbm_over.work);

list_for_each_entry(prgrp, &rdt_all_groups, rdtgroup_list) {
@@ -759,9 +761,9 @@ static struct mon_evt mbm_local_event = {
/*
* Initialize the event list for the resource.
*
- * Note that MBM events are also part of RDT_RESOURCE_L3 resource
- * because as per the SDM the total and local memory bandwidth
- * are enumerated as part of L3 monitoring.
+ * Monitor events can either be part of RDT_RESOURCE_L3 resource,
+ * or they may be per NUMA node on systems with sub-NUMA cluster
+ * enabled and are then in the RDT_RESOURCE_NODE resource.
*/
static void l3_mon_evt_init(struct rdt_resource *r)
{
@@ -773,6 +775,8 @@ static void l3_mon_evt_init(struct rdt_resource *r)
list_add_tail(&mbm_total_event.list, &r->evt_list);
if (is_mbm_local_enabled())
list_add_tail(&mbm_local_event.list, &r->evt_list);
+
+ mon_resource = r;
}

int __init rdt_get_mon_l3_config(struct rdt_resource *r)
--
2.40.1