[apparmor] [RFC 9/9] apparmor: Switch unconfined and in tree labels to managed ref mode

[Neeraj Upadhyay]

Switch unconfined and in-tree labels to percpu managed
mode of percpu rcuref. This helps avoid memory contention
in ref get and put operations.

Signed-off-by: Neeraj Upadhyay <Neeraj.Upadhyay at amd.com>
---
 security/apparmor/label.c     | 1 +
 security/apparmor/policy_ns.c | 2 ++
 2 files changed, 3 insertions(+)

diff --git a/security/apparmor/label.c b/security/apparmor/label.c
index f28dec1c3e70..57fcd5b3e48a 100644
--- a/security/apparmor/label.c
+++ b/security/apparmor/label.c
@@ -710,6 +710,7 @@ static struct aa_label *__label_insert(struct aa_labelset *ls,
 	rb_link_node(&label->node, parent, new);
 	rb_insert_color(&label->node, &ls->root);
 	label->flags |= FLAG_IN_TREE;
+	percpu_rcuref_manage(&label->count);
 
 	return aa_get_label(label);
 }
diff --git a/security/apparmor/policy_ns.c b/security/apparmor/policy_ns.c
index 1f02cfe1d974..ff261b119c53 100644
--- a/security/apparmor/policy_ns.c
+++ b/security/apparmor/policy_ns.c
@@ -124,6 +124,7 @@ static struct aa_ns *alloc_ns(const char *prefix, const char *name)
 		goto fail_unconfined;
 	/* ns and ns->unconfined share ns->unconfined refcount */
 	ns->unconfined->ns = ns;
+	percpu_rcuref_manage(&ns->unconfined->label.count);
 
 	atomic_set(&ns->uniq_null, 0);
 
@@ -377,6 +378,7 @@ int __init aa_alloc_root_ns(void)
 	}
 	kernel_t = &kernel_p->label;
 	root_ns->unconfined->ns = aa_get_ns(root_ns);
+	percpu_rcuref_manage(&root_ns->unconfined->label.count);
 
 	return 0;
 }
-- 
2.34.1