tipc: Optimize detection of duplicate media registration

Streamlines the detection of an attempt to register a TIPC media structure
using an already registered name or type identifier. The revised logic now
reuses an existing routine to detect an existing name and no longer
unnecessarily manipulates the media type counter during an unsuccessful
registration attempt.

Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

1 files changed, 21 insertions, 19 deletions

diff --git a/net/tipc/bearer.c b/net/tipc/bearer.c
index 75af271b9cf..9ff89207846 100644
--- a/net/tipc/bearer.c
+++ b/net/tipc/bearer.c
@@ -81,6 +81,21 @@ static struct media *media_find(const char *name)
 }
 
 /**
+ * media_find_id - locates specified media object by type identifier
+ */
+
+static struct media *media_find_id(u8 type)
+{
+	u32 i;
+
+	for (i = 0; i < media_count; i++) {
+		if (media_list[i].type_id == type)
+			return &media_list[i];
+	}
+	return NULL;
+}
+
+/**
  * tipc_register_media - register a media type
  *
  * Bearers for this media type must be activated separately at a later stage.
@@ -88,8 +103,6 @@ static struct media *media_find(const char *name)
 
 int  tipc_register_media(struct media *m_ptr)
 {
-	u32 media_id;
-	u32 i;
 	int res = -EINVAL;
 
 	write_lock_bh(&tipc_net_lock);
@@ -121,29 +134,18 @@ int  tipc_register_media(struct media *m_ptr)
 		goto exit;
 	}
 
-	media_id = media_count++;
-	if (media_id >= MAX_MEDIA) {
+	if (media_count >= MAX_MEDIA) {
 		warn("Media <%s> rejected, media limit reached (%u)\n",
 		     m_ptr->name, MAX_MEDIA);
-		media_count--;
 		goto exit;
 	}
-	for (i = 0; i < media_id; i++) {
-		if (media_list[i].type_id == m_ptr->type_id) {
-			warn("Media <%s> rejected, duplicate type (%u)\n",
-			     m_ptr->name, m_ptr->type_id);
-			media_count--;
-			goto exit;
-		}
-		if (!strcmp(m_ptr->name, media_list[i].name)) {
-			warn("Media <%s> rejected, duplicate name\n",
-			     m_ptr->name);
-			media_count--;
-			goto exit;
-		}
+	if (media_find(m_ptr->name) || media_find_id(m_ptr->type_id)) {
+		warn("Media <%s> rejected, already registered\n", m_ptr->name);
+		goto exit;
 	}
 
-	media_list[media_id] = *m_ptr;
+	media_list[media_count] = *m_ptr;
+	media_count++;
 	res = 0;
 exit:
 	write_unlock_bh(&tipc_net_lock);