[PATCH v3 21/26] fs-x86/resctrl: Handle RDT_RESOURCE_PERF_PKG in domain create/delete

[Tony Luck]

Add a new rdt_perf_pkg_mon_domain structure. This only consists of
the common rdt_domain_hdr as there is no need for any per-domain
data structures.

Use as much as possible of the existing domain setup and tear down
infrastructure. In many cases the RDT_RESOURCE_PERF_PKG uses the
same functions but just skips over the pieces it does not need.

Signed-off-by: Tony Luck <tony.luck@xxxxxxxxx>
---
 include/linux/resctrl.h            |  8 ++++++++
 arch/x86/kernel/cpu/resctrl/core.c | 32 ++++++++++++++++++++++++++++++
 fs/resctrl/rdtgroup.c              | 11 ++++++++--
 3 files changed, 49 insertions(+), 2 deletions(-)

diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index c03e7dc1f009..6f598a64b192 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -169,6 +169,14 @@ struct rdt_mon_domain {
 	int				cqm_work_cpu;
 };
 
+/**
+ * struct rdt_perf_pkg_mon_domain - CPUs sharing an Intel-PMT-scoped resctrl monitor resource
+ * @hdr:               common header for different domain types
+ */
+struct rdt_perf_pkg_mon_domain {
+	struct rdt_domain_hdr   hdr;
+};
+
 /**
  * struct resctrl_cache - Cache allocation related data
  * @cbm_len:		Length of the cache bit mask
diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 9578d9c7260c..6f5d52a8219b 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -542,6 +542,29 @@ static void setup_l3_mon_domain(int cpu, int id, struct rdt_resource *r, struct
 	}
 }
 
+static void setup_intel_aet_mon_domain(int cpu, int id, struct rdt_resource *r,
+				       struct list_head *add_pos)
+{
+	struct rdt_perf_pkg_mon_domain *d;
+	int err;
+
+	d = kzalloc_node(sizeof(*d), GFP_KERNEL, cpu_to_node(cpu));
+	if (!d)
+		return;
+
+	d->hdr.id = id;
+	d->hdr.type = DOMTYPE(r->rid, DOMTYPE_MON);
+	cpumask_set_cpu(cpu, &d->hdr.cpu_mask);
+	list_add_tail_rcu(&d->hdr.list, add_pos);
+
+	err = resctrl_online_mon_domain(r, &d->hdr);
+	if (err) {
+		list_del_rcu(&d->hdr.list);
+		synchronize_rcu();
+		kfree(d);
+	}
+}
+
 static void domain_add_cpu_mon(int cpu, struct rdt_resource *r)
 {
 	int id = get_domain_id_from_scope(cpu, r->mon_scope);
@@ -571,6 +594,9 @@ static void domain_add_cpu_mon(int cpu, struct rdt_resource *r)
 	case RDT_RESOURCE_L3:
 		setup_l3_mon_domain(cpu, id, r, add_pos);
 		break;
+	case RDT_RESOURCE_PERF_PKG:
+		setup_intel_aet_mon_domain(cpu, id, r, add_pos);
+		break;
 	default:
 		WARN_ON_ONCE(1);
 	}
@@ -668,6 +694,12 @@ static void domain_remove_cpu_mon(int cpu, struct rdt_resource *r)
 		synchronize_rcu();
 		mon_domain_free(hw_dom);
 		break;
+	case RDT_RESOURCE_PERF_PKG:
+		resctrl_offline_mon_domain(r, d);
+		list_del_rcu(&hdr->list);
+		synchronize_rcu();
+		kfree(container_of(hdr, struct rdt_perf_pkg_mon_domain, hdr));
+		break;
 	}
 }
 
diff --git a/fs/resctrl/rdtgroup.c b/fs/resctrl/rdtgroup.c
index 5ca6de6a6e5c..34fcd20f8dd7 100644
--- a/fs/resctrl/rdtgroup.c
+++ b/fs/resctrl/rdtgroup.c
@@ -4020,6 +4020,9 @@ void resctrl_offline_mon_domain(struct rdt_resource *r, struct rdt_mon_domain *d
 	if (resctrl_mounted && resctrl_arch_mon_capable())
 		rmdir_mondata_subdir_allrdtgrp(r, &d->hdr);
 
+	if (r->rid == RDT_RESOURCE_PERF_PKG)
+		goto done;
+
 	if (resctrl_is_mbm_enabled())
 		cancel_delayed_work(&d->mbm_over);
 	if (resctrl_arch_is_llc_occupancy_enabled() && has_busy_rmid(d)) {
@@ -4036,7 +4039,7 @@ void resctrl_offline_mon_domain(struct rdt_resource *r, struct rdt_mon_domain *d
 	}
 
 	domain_destroy_mon_state(d);
-
+done:
 	mutex_unlock(&rdtgroup_mutex);
 }
 
@@ -4104,12 +4107,15 @@ int resctrl_online_ctrl_domain(struct rdt_resource *r, struct rdt_ctrl_domain *d
 int resctrl_online_mon_domain(struct rdt_resource *r, struct rdt_domain_hdr *hdr)
 {
 	struct rdt_mon_domain *d;
-	int err;
+	int err = 0;
 
 	WARN_ON_ONCE(hdr->type != DOMTYPE(r->rid, DOMTYPE_MON));
 	d = container_of(hdr, struct rdt_mon_domain, hdr);
 	mutex_lock(&rdtgroup_mutex);
 
+	if (r->rid == RDT_RESOURCE_PERF_PKG)
+		goto do_mkdir;
+
 	err = domain_setup_mon_state(r, d);
 	if (err)
 		goto out_unlock;
@@ -4123,6 +4129,7 @@ int resctrl_online_mon_domain(struct rdt_resource *r, struct rdt_domain_hdr *hdr
 	if (resctrl_arch_is_llc_occupancy_enabled())
 		INIT_DELAYED_WORK(&d->cqm_limbo, cqm_handle_limbo);
 
+do_mkdir:
 	/*
 	 * If the filesystem is not mounted then only the default resource group
 	 * exists. Creation of its directories is deferred until mount time
-- 
2.48.1