[PATCH RFC v3 08/15] arm_mpam: Include all MSC components during domain setup

[Fenghua Yu <fenghuay@nvidia.com>]

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.

A memory-class MSC keeps control_mode legacy and names its control NODE,
so the schemata line is MB_NODE in both legacy and native mode. A cache
MSC keeps the MB line.

Signed-off-by: Fenghua Yu <fenghuay@nvidia.com>
---
 drivers/resctrl/mpam_resctrl.c | 209 +++++++++++++++++++--------------
 fs/resctrl/ctrlmondata.c       |   1 +
 include/linux/resctrl.h        |   3 +
 3 files changed, 127 insertions(+), 86 deletions(-)

diff --git a/drivers/resctrl/mpam_resctrl.c b/drivers/resctrl/mpam_resctrl.c
index 72302f6021d7..ac0c488abe12 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;
+
+		if (r->mon_capable)
+			return true;
+	}
 
-	/* All monitors are presented as being on the L3 cache */
-	return l3->mon_capable;
+	return false;
 }
 
 bool resctrl_arch_is_evt_configurable(enum resctrl_event_id evt)
@@ -1293,8 +1309,18 @@ static int mpam_resctrl_control_init(struct mpam_resctrl_res *res)
 		break;
 	case RDT_RESOURCE_MBA:
 		r->ctrl_scope = RESCTRL_L3_CACHE;
+		/*
+		 * control_mode stays legacy. emulated_by is left empty so
+		 * legacy and native mode expose the same schemata line.
+		 * A memory-class MSC is node-scoped, so that line is
+		 * MB_NODE. A cache MSC keeps the MB line.
+		 */
+		r->ctrl_mode = RESCTRL_CTRL_MODE_LEGACY;
 		mpam_ctrl->r_ctrl.type = RESCTRL_CTRL_SCALAR;
-		mpam_ctrl->r_ctrl.name = RESCTRL_CTRL_NAME_DEF;
+		if (mpam_class_memory(class))
+			mpam_ctrl->r_ctrl.name = RESCTRL_CTRL_NAME_NODE;
+		else
+			mpam_ctrl->r_ctrl.name = RESCTRL_CTRL_NAME_DEF;
 		INIT_LIST_HEAD_RCU(&mpam_ctrl->r_ctrl.domains);
 		INIT_LIST_HEAD(&mpam_ctrl->r_ctrl.emulated_by);
 
@@ -1731,13 +1757,12 @@ 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);
@@ -1745,28 +1770,17 @@ 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)
@@ -1784,13 +1798,12 @@ 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;
@@ -1801,24 +1814,14 @@ 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
@@ -1833,7 +1836,7 @@ 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;
@@ -1870,25 +1873,32 @@ 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;
 	}
 
@@ -1896,14 +1906,19 @@ 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;
 	}
 
@@ -1914,6 +1929,7 @@ 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) {
@@ -1924,30 +1940,40 @@ 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);
 			}
 		}
 	}
@@ -1961,6 +1987,7 @@ 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);
 
@@ -1976,31 +2003,41 @@ 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);
-			}
-		}
 	}
 }
 
diff --git a/fs/resctrl/ctrlmondata.c b/fs/resctrl/ctrlmondata.c
index 4bc7090ad0c7..77a2f2e877a6 100644
--- a/fs/resctrl/ctrlmondata.c
+++ b/fs/resctrl/ctrlmondata.c
@@ -359,6 +359,7 @@ static const char * const resctrl_ctrl_name[] = {
 	[RESCTRL_CTRL_NAME_DEF]		= "",
 	[RESCTRL_CTRL_NAME_MIN]		= "MIN",
 	[RESCTRL_CTRL_NAME_MAX]		= "MAX",
+	[RESCTRL_CTRL_NAME_NODE]	= "NODE",
 	[RESCTRL_CTRL_NAME_REGION0_MIN]		= "REGION0_MIN",
 	[RESCTRL_CTRL_NAME_REGION0_MAX]		= "REGION0_MAX",
 };
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 195c0948b26d..3c4675656b51 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -398,6 +398,8 @@ struct resctrl_mon {
  *				has the same name as the resource.
  * @RESCTRL_CTRL_NAME_MIN:	"MIN"
  * @RESCTRL_CTRL_NAME_MAX:	"MAX"
+ * @RESCTRL_CTRL_NAME_NODE:	"NODE". With resource name "MB" the schemata
+ *				line is "MB_NODE".
  * @RESCTRL_CTRL_NAME_REGION0_MIN:	"REGION0_MIN"
  * @RESCTRL_CTRL_NAME_REGION0_MAX:	"REGION0_MAX"
  */
@@ -405,6 +407,7 @@ enum resctrl_ctrl_name {
 	RESCTRL_CTRL_NAME_DEF,
 	RESCTRL_CTRL_NAME_MIN,
 	RESCTRL_CTRL_NAME_MAX,
+	RESCTRL_CTRL_NAME_NODE,
 	RESCTRL_CTRL_NAME_REGION0_MIN,
 	RESCTRL_CTRL_NAME_REGION0_MAX,
 	RESCTRL_CTRL_NAME_LAST = RESCTRL_CTRL_NAME_REGION0_MAX
-- 
2.53.0