[PATCH 16/23] arm_mpam: Include all MSC components during domain setup
From: Fenghua Yu
Date: Thu Jul 16 2026 - 17:09:55 EST
Iterate all MSC components per CPU when creating and looking up control
and monitor domains on the controls branch. Key monitor domains by
component, support MBA mon_capable lookup, and report mon capability
from any L3 or MBA monitor resource.
Signed-off-by: Fenghua Yu <fenghuay@xxxxxxxxxx>
---
drivers/resctrl/mpam_resctrl.c | 197 +++++++++++++++++++--------------
1 file changed, 112 insertions(+), 85 deletions(-)
diff --git a/drivers/resctrl/mpam_resctrl.c b/drivers/resctrl/mpam_resctrl.c
index 86458a56a526..f67647d95bbe 100644
--- a/drivers/resctrl/mpam_resctrl.c
+++ b/drivers/resctrl/mpam_resctrl.c
@@ -95,11 +95,27 @@ static bool mpam_class_memory(struct mpam_class *class)
bool resctrl_arch_mon_capable(void)
{
- struct mpam_resctrl_res *res = &mpam_resctrl_controls[RDT_RESOURCE_L3];
- struct rdt_resource *l3 = &res->resctrl_res;
+ enum resctrl_event_id eventid;
+ struct mpam_resctrl_mon *mon;
+ struct mpam_resctrl_res *res;
+ struct rdt_resource *r;
+
+ for_each_mpam_resctrl_mon(mon, eventid) {
+ if (!mon->class)
+ continue; // dummy resource
+
+ if (mpam_class_memory(mon->class))
+ res = &mpam_resctrl_controls[RDT_RESOURCE_MBA];
+ else
+ res = &mpam_resctrl_controls[RDT_RESOURCE_L3];
+
+ r = &res->resctrl_res;
- /* All monitors are presented as being on the L3 cache */
- return l3->mon_capable;
+ if (r->mon_capable)
+ return true;
+ }
+
+ return false;
}
bool resctrl_arch_is_evt_configurable(enum resctrl_event_id evt)
@@ -1719,13 +1735,12 @@ static struct mpam_component *find_component(struct mpam_class *class, int cpu)
static struct mpam_resctrl_dom *
mpam_resctrl_alloc_ctrl_domain(unsigned int cpu, struct mpam_resctrl_res *res,
- struct resctrl_ctrl *ctrl)
+ struct resctrl_ctrl *ctrl,
+ struct mpam_component *comp)
{
int err;
struct mpam_resctrl_dom *dom;
struct rdt_ctrl_domain *ctrl_d;
- struct mpam_class *class = res->class;
- struct mpam_component *comp_iter, *ctrl_comp;
struct rdt_resource *r = &res->resctrl_res;
lockdep_assert_held(&domain_list_lock);
@@ -1733,28 +1748,17 @@ mpam_resctrl_alloc_ctrl_domain(unsigned int cpu, struct mpam_resctrl_res *res,
if (!r->alloc_capable)
return ERR_PTR(-EINVAL);
- ctrl_comp = NULL;
- guard(srcu)(&mpam_srcu);
- list_for_each_entry_srcu(comp_iter, &class->components, class_list,
- srcu_read_lock_held(&mpam_srcu)) {
- if (cpumask_test_cpu(cpu, &comp_iter->affinity)) {
- ctrl_comp = comp_iter;
- break;
- }
- }
-
- /* class has no component for this CPU */
- if (WARN_ON_ONCE(!ctrl_comp))
+ if (WARN_ON_ONCE(!comp))
return ERR_PTR(-EINVAL);
dom = kzalloc_node(sizeof(*dom), GFP_KERNEL, cpu_to_node(cpu));
if (!dom)
return ERR_PTR(-ENOMEM);
- dom->ctrl_comp = ctrl_comp;
+ dom->ctrl_comp = comp;
ctrl_d = &dom->resctrl_ctrl_dom;
- mpam_resctrl_domain_hdr_init(cpu, ctrl_comp, r->rid, &ctrl_d->hdr);
+ mpam_resctrl_domain_hdr_init(cpu, comp, r->rid, &ctrl_d->hdr);
ctrl_d->hdr.type = RESCTRL_CTRL_DOMAIN;
err = resctrl_online_ctrl_domain(r, ctrl, ctrl_d);
if (err)
@@ -1772,13 +1776,12 @@ mpam_resctrl_alloc_ctrl_domain(unsigned int cpu, struct mpam_resctrl_res *res,
}
static struct mpam_resctrl_dom *
-mpam_resctrl_alloc_mon_domain(unsigned int cpu, struct mpam_resctrl_res *res)
+mpam_resctrl_alloc_mon_domain(unsigned int cpu, struct mpam_resctrl_res *res,
+ struct mpam_component *comp)
{
int err;
struct mpam_resctrl_dom *dom;
struct rdt_l3_mon_domain *mon_d;
- struct mpam_class *class = res->class;
- struct mpam_component *comp_iter, *ctrl_comp;
struct rdt_resource *r = &res->resctrl_res;
struct mpam_component *any_mon_comp = NULL;
struct mpam_resctrl_mon *mon;
@@ -1789,24 +1792,14 @@ mpam_resctrl_alloc_mon_domain(unsigned int cpu, struct mpam_resctrl_res *res)
if (!r->mon_capable)
return ERR_PTR(-EINVAL);
- ctrl_comp = NULL;
- guard(srcu)(&mpam_srcu);
- list_for_each_entry_srcu(comp_iter, &class->components, class_list,
- srcu_read_lock_held(&mpam_srcu)) {
- if (cpumask_test_cpu(cpu, &comp_iter->affinity)) {
- ctrl_comp = comp_iter;
- break;
- }
- }
-
- /* class has no component for this CPU */
- if (WARN_ON_ONCE(!ctrl_comp))
+ if (WARN_ON_ONCE(!comp))
return ERR_PTR(-EINVAL);
dom = kzalloc_node(sizeof(*dom), GFP_KERNEL, cpu_to_node(cpu));
if (!dom)
return ERR_PTR(-ENOMEM);
+ dom->ctrl_comp = comp;
/*
* Even if the monitor domain is backed by a different
@@ -1821,7 +1814,7 @@ mpam_resctrl_alloc_mon_domain(unsigned int cpu, struct mpam_resctrl_res *res)
if (!mon->class)
continue; // dummy resource
- mon_comp = find_component(mon->class, cpu);
+ mon_comp = comp ? comp : find_component(mon->class, cpu);
dom->mon_comp[eventid] = mon_comp;
if (mon_comp)
any_mon_comp = mon_comp;
@@ -1858,25 +1851,32 @@ mpam_resctrl_alloc_mon_domain(unsigned int cpu, struct mpam_resctrl_res *res)
* for anything that is not a cache.
*/
static struct mpam_resctrl_dom *
-mpam_resctrl_get_mon_domain_from_cpu(int cpu, struct mpam_resctrl_res *res)
+mpam_resctrl_get_mon_domain_from_cpu(int cpu, struct mpam_resctrl_res *res,
+ struct mpam_component *comp)
{
- int cache_id;
struct mpam_resctrl_dom *dom;
struct rdt_resource *r = &res->resctrl_res;
+ int id;
lockdep_assert_cpus_held();
- if (r->rid != RDT_RESOURCE_L3)
- return ERR_PTR(-EINVAL);
+ if (!r->mon_capable || !res->class || !comp)
+ return NULL;
- if (!res->class)
- return ERR_PTR(-EINVAL);
- cache_id = get_cpu_cacheinfo_id(cpu, 3);
- if (cache_id < 0)
- return ERR_PTR(-EINVAL);
+ if (r->rid == RDT_RESOURCE_L3) {
+ id = get_cpu_cacheinfo_id(cpu, 3);
+ if (id < 0)
+ return NULL;
+ } else if (r->rid == RDT_RESOURCE_MBA) {
+ id = comp->comp_id;
+ } else {
+ return NULL;
+ }
- list_for_each_entry_rcu(dom, &res->resctrl_res.mon_domains, resctrl_mon_dom.hdr.list) {
- if (dom->resctrl_mon_dom.hdr.id == cache_id)
+ list_for_each_entry_rcu(dom, &r->mon_domains, resctrl_mon_dom.hdr.list) {
+ if (dom->ctrl_comp != comp)
+ continue;
+ if (dom->resctrl_mon_dom.hdr.id == id)
return dom;
}
@@ -1884,14 +1884,19 @@ mpam_resctrl_get_mon_domain_from_cpu(int cpu, struct mpam_resctrl_res *res)
}
static struct mpam_resctrl_dom *
-mpam_resctrl_get_ctrl_domain_from_cpu(int cpu, struct resctrl_ctrl *ctrl)
+mpam_resctrl_get_ctrl_domain_from_cpu(int cpu, struct mpam_resctrl_res *res,
+ struct resctrl_ctrl *ctrl,
+ struct mpam_component *comp)
{
struct mpam_resctrl_dom *dom;
lockdep_assert_cpus_held();
+ if (!comp)
+ return NULL;
+
list_for_each_entry_rcu(dom, &ctrl->domains, resctrl_ctrl_dom.hdr.list) {
- if (cpumask_test_cpu(cpu, &dom->ctrl_comp->affinity))
+ if (dom->ctrl_comp == comp)
return dom;
}
@@ -1902,6 +1907,7 @@ int mpam_resctrl_online_cpu(unsigned int cpu)
{
struct mpam_resctrl_res *res;
enum resctrl_res_level rid;
+ struct mpam_component *comp;
guard(mutex)(&domain_list_lock);
for_each_mpam_resctrl_control(res, rid) {
@@ -1912,30 +1918,40 @@ int mpam_resctrl_online_cpu(unsigned int cpu)
if (!res->class)
continue; // dummy_resource;
- if (r->alloc_capable) {
- for_each_resource_ctrl(ctrl, r) {
- dom = mpam_resctrl_get_ctrl_domain_from_cpu(cpu, ctrl);
- if (!dom) {
- dom = mpam_resctrl_alloc_ctrl_domain(cpu, res, ctrl);
+ guard(srcu)(&mpam_srcu);
+ list_for_each_entry_srcu(comp, &res->class->components, class_list,
+ srcu_read_lock_held(&mpam_srcu)) {
+ if (!cpumask_test_cpu(cpu, &comp->affinity))
+ continue;
+
+ if (r->alloc_capable) {
+ for_each_resource_ctrl(ctrl, r) {
+ dom = mpam_resctrl_get_ctrl_domain_from_cpu(cpu, res,
+ ctrl, comp);
+ if (!dom) {
+ dom = mpam_resctrl_alloc_ctrl_domain(cpu, res,
+ ctrl, comp);
+ } else {
+ struct rdt_ctrl_domain *ctrl_d =
+ &dom->resctrl_ctrl_dom;
+
+ mpam_resctrl_online_domain_hdr(cpu, &ctrl_d->hdr);
+ }
if (IS_ERR(dom))
return PTR_ERR(dom);
+ }
+ }
+ if (r->mon_capable) {
+ dom = mpam_resctrl_get_mon_domain_from_cpu(cpu, res, comp);
+ if (!dom) {
+ dom = mpam_resctrl_alloc_mon_domain(cpu, res, comp);
} else {
- struct rdt_ctrl_domain *ctrl_d = &dom->resctrl_ctrl_dom;
+ struct rdt_l3_mon_domain *mon_d = &dom->resctrl_mon_dom;
- mpam_resctrl_online_domain_hdr(cpu, &ctrl_d->hdr);
+ mpam_resctrl_online_domain_hdr(cpu, &mon_d->hdr);
}
- }
- }
- if (r->mon_capable) {
- dom = mpam_resctrl_get_mon_domain_from_cpu(cpu, res);
- if (!dom) {
- dom = mpam_resctrl_alloc_mon_domain(cpu, res);
if (IS_ERR(dom))
return PTR_ERR(dom);
- } else {
- struct rdt_l3_mon_domain *mon_d = &dom->resctrl_mon_dom;
-
- mpam_resctrl_online_domain_hdr(cpu, &mon_d->hdr);
}
}
}
@@ -1949,6 +1965,7 @@ void mpam_resctrl_offline_cpu(unsigned int cpu)
{
struct mpam_resctrl_res *res;
enum resctrl_res_level rid;
+ struct mpam_component *comp;
resctrl_offline_cpu(cpu);
@@ -1964,31 +1981,41 @@ void mpam_resctrl_offline_cpu(unsigned int cpu)
if (!res->class)
continue; // dummy resource
- if (r->alloc_capable) {
- for_each_resource_ctrl(ctrl, r) {
- dom = mpam_resctrl_get_ctrl_domain_from_cpu(cpu, ctrl);
+ guard(srcu)(&mpam_srcu);
+ list_for_each_entry_srcu(comp, &res->class->components, class_list,
+ srcu_read_lock_held(&mpam_srcu)) {
+ if (!cpumask_test_cpu(cpu, &comp->affinity))
+ continue;
+
+ if (r->alloc_capable) {
+ for_each_resource_ctrl(ctrl, r) {
+ dom = mpam_resctrl_get_ctrl_domain_from_cpu(cpu, res,
+ ctrl, comp);
+ if (WARN_ON_ONCE(!dom))
+ continue;
+ ctrl_d = &dom->resctrl_ctrl_dom;
+ dom_empty = mpam_resctrl_offline_domain_hdr(cpu,
+ &ctrl_d->hdr);
+ if (dom_empty) {
+ resctrl_offline_ctrl_domain(&res->resctrl_res, ctrl,
+ ctrl_d);
+ kfree(dom);
+ }
+ }
+ }
+
+ if (r->mon_capable) {
+ dom = mpam_resctrl_get_mon_domain_from_cpu(cpu, res, comp);
if (WARN_ON_ONCE(!dom))
continue;
- ctrl_d = &dom->resctrl_ctrl_dom;
- dom_empty = mpam_resctrl_offline_domain_hdr(cpu, &ctrl_d->hdr);
+ mon_d = &dom->resctrl_mon_dom;
+ dom_empty = mpam_resctrl_offline_domain_hdr(cpu, &mon_d->hdr);
if (dom_empty) {
- resctrl_offline_ctrl_domain(&res->resctrl_res, ctrl, ctrl_d);
+ resctrl_offline_mon_domain(&res->resctrl_res, &mon_d->hdr);
kfree(dom);
}
}
}
-
- if (r->mon_capable) {
- dom = mpam_resctrl_get_mon_domain_from_cpu(cpu, res);
- if (WARN_ON_ONCE(!dom))
- continue;
- mon_d = &dom->resctrl_mon_dom;
- dom_empty = mpam_resctrl_offline_domain_hdr(cpu, &mon_d->hdr);
- if (dom_empty) {
- resctrl_offline_mon_domain(&res->resctrl_res, &mon_d->hdr);
- kfree(dom);
- }
- }
}
}
--
2.43.0