- Use refcount(9) API to manage node and hook refcounting.

- Make ng_unref_node() void, since caller shouldn't be
  interested in whether node is valid after call or not,
  since it can't be guaranteed to be valid. [1]

Ok from:	julian [1]

2 files changed, 10 insertions, 18 deletions

diff --git a/sys/netgraph/netgraph.h b/sys/netgraph/netgraph.h
index 8dbf0b5..51fe440 100644
--- a/sys/netgraph/netgraph.h
+++ b/sys/netgraph/netgraph.h
@@ -53,6 +53,7 @@
 #include <sys/malloc.h>
 #include <sys/module.h>
 #include <sys/mutex.h>
+#include <sys/refcount.h>
 
 #ifdef HAVE_KERNEL_OPTION_HEADERS
 #include "opt_netgraph.h"
@@ -137,7 +138,7 @@ struct ng_hook {
  * If you can't do it with these you probably shouldn;t be doing it.
  */
 void ng_unref_hook(hook_p hook); /* don't move this */
-#define	_NG_HOOK_REF(hook)	atomic_add_int(&(hook)->hk_refs, 1)
+#define	_NG_HOOK_REF(hook)	refcount_acquire(&(hook)->hk_refs)
 #define _NG_HOOK_NAME(hook)	((hook)->hk_name)
 #define _NG_HOOK_UNREF(hook)	ng_unref_hook(hook)
 #define	_NG_HOOK_SET_PRIVATE(hook, val)	do {(hook)->hk_private = val;} while (0)
@@ -396,11 +397,11 @@ struct ng_node {
  * Public methods for nodes.
  * If you can't do it with these you probably shouldn't be doing it.
  */
-int	ng_unref_node(node_p node); /* don't move this */
+void	ng_unref_node(node_p node); /* don't move this */
 #define _NG_NODE_NAME(node)	((node)->nd_name + 0)
 #define _NG_NODE_HAS_NAME(node)	((node)->nd_name[0] + 0)
 #define _NG_NODE_ID(node)	((node)->nd_ID + 0)
-#define	_NG_NODE_REF(node)	atomic_add_int(&(node)->nd_refs, 1)
+#define	_NG_NODE_REF(node)	refcount_acquire(&(node)->nd_refs)
 #define	_NG_NODE_UNREF(node)	ng_unref_node(node)
 #define	_NG_NODE_SET_PRIVATE(node, val)	do {(node)->nd_private = val;} while (0)
 #define	_NG_NODE_PRIVATE(node)	((node)->nd_private)
diff --git a/sys/netgraph/ng_base.c b/sys/netgraph/ng_base.c
index f67f247f..0918193 100644
--- a/sys/netgraph/ng_base.c
+++ b/sys/netgraph/ng_base.c
@@ -772,18 +772,14 @@ ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3)
  * Remove a reference to the node, possibly the last.
  * deadnode always acts as it it were the last.
  */
-int
+void
 ng_unref_node(node_p node)
 {
-	int v;
-
-	if (node == &ng_deadnode) {
-		return (0);
-	}
 
-	v = atomic_fetchadd_int(&node->nd_refs, -1);
+	if (node == &ng_deadnode)
+		return;
 
-	if (v == 1) { /* we were the last */
+	if (refcount_release(&node->nd_refs)) { /* we were the last */
 
 		mtx_lock(&ng_namehash_mtx);
 		node->nd_type->refs--; /* XXX maybe should get types lock? */
@@ -797,7 +793,6 @@ ng_unref_node(node_p node)
 		mtx_destroy(&node->nd_input_queue.q_mtx);
 		NG_FREE_NODE(node);
 	}
-	return (v - 1);
 }
 
 /************************************************************************
@@ -963,15 +958,11 @@ ng_unname(node_p node)
 void
 ng_unref_hook(hook_p hook)
 {
-	int v;
 
-	if (hook == &ng_deadhook) {
+	if (hook == &ng_deadhook)
 		return;
-	}
-
-	v = atomic_fetchadd_int(&hook->hk_refs, -1);
 
-	if (v == 1) { /* we were the last */
+	if (refcount_release(&hook->hk_refs)) { /* we were the last */
 		if (_NG_HOOK_NODE(hook)) /* it'll probably be ng_deadnode */
 			_NG_NODE_UNREF((_NG_HOOK_NODE(hook)));
 		NG_FREE_HOOK(hook);