commit 5702dbab687e19792102200b085108f00ab820c9
author Jon Paul Maloy <jon.maloy@ericsson.com> Tue Dec 10 20:45:39 2013 -0800
committer David S. Miller <davem@davemloft.net> Wed Dec 11 00:17:42 2013 -0500
tree a3f19fccfbaf4043d0de34a76fd476efe9219920
parent d77b3831f7d59d69aa49d5d1df10bbe56671dc5d

tipc: initiate media type array at compile time

Communication media types are abstracted through the struct 'tipc_media',
one per media type. These structs are allocated statically inside their
respective media file.

Furthermore, in order to be able to reach all instances from a central
location, we keep a static array with pointers to these structs. This
array is currently initialized at runtime, under protection of
tipc_net_lock. However, since the contents of the array itself never
changes after initialization, we can just as well initialize it at
compile time and make it 'const', at the same time making it obvious
that no lock protection is needed here.

This commit makes the array constant and removes the redundant lock
protection.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/tipc/bearer.c

diff --git a/net/tipc/bearer.c b/net/tipc/bearer.c
index c2101c0..826aa9f 100644
--- a/net/tipc/bearer.c
+++ b/net/tipc/bearer.c
@@ -1,7 +1,7 @@
 /*
  * net/tipc/bearer.c: TIPC bearer code
  *
- * Copyright (c) 1996-2006, Ericsson AB
+ * Copyright (c) 1996-2006, 2013, Ericsson AB
  * Copyright (c) 2004-2006, 2010-2011, Wind River Systems
  * All rights reserved.
  *
@@ -41,8 +41,13 @@
 
 #define MAX_ADDR_STR 60
 
-static struct tipc_media *media_list[MAX_MEDIA];
-static u32 media_count;
+static struct tipc_media * const media_list[] = {
+	&eth_media_info,
+#ifdef CONFIG_TIPC_MEDIA_IB
+	&ib_media_info,
+#endif
+	NULL
+};
 
 struct tipc_bearer tipc_bearers[MAX_BEARERS];
 
@@ -55,11 +60,11 @@
 {
 	u32 i;
 
-	for (i = 0; i < media_count; i++) {
+	for (i = 0; media_list[i] != NULL; i++) {
 		if (!strcmp(media_list[i]->name, name))
-			return media_list[i];
+			break;
 	}
-	return NULL;
+	return media_list[i];
 }
 
 /**
@@ -69,44 +74,11 @@
 {
 	u32 i;
 
-	for (i = 0; i < media_count; i++) {
+	for (i = 0; media_list[i] != NULL; i++) {
 		if (media_list[i]->type_id == type)
-			return media_list[i];
+			break;
 	}
-	return NULL;
-}
-
-/**
- * tipc_register_media - register a media type
- *
- * Bearers for this media type must be activated separately at a later stage.
- */
-int tipc_register_media(struct tipc_media *m_ptr)
-{
-	int res = -EINVAL;
-
-	write_lock_bh(&tipc_net_lock);
-
-	if ((strlen(m_ptr->name) + 1) > TIPC_MAX_MEDIA_NAME)
-		goto exit;
-	if (m_ptr->priority > TIPC_MAX_LINK_PRI)
-		goto exit;
-	if ((m_ptr->tolerance < TIPC_MIN_LINK_TOL) ||
-	    (m_ptr->tolerance > TIPC_MAX_LINK_TOL))
-		goto exit;
-	if (media_count >= MAX_MEDIA)
-		goto exit;
-	if (tipc_media_find(m_ptr->name) || media_find_id(m_ptr->type_id))
-		goto exit;
-
-	media_list[media_count] = m_ptr;
-	media_count++;
-	res = 0;
-exit:
-	write_unlock_bh(&tipc_net_lock);
-	if (res)
-		pr_warn("Media <%s> registration error\n", m_ptr->name);
-	return res;
+	return media_list[i];
 }
 
 /**
@@ -144,13 +116,11 @@
 	if (!buf)
 		return NULL;
 
-	read_lock_bh(&tipc_net_lock);
-	for (i = 0; i < media_count; i++) {
+	for (i = 0; media_list[i] != NULL; i++) {
 		tipc_cfg_append_tlv(buf, TIPC_TLV_MEDIA_NAME,
 				    media_list[i]->name,
 				    strlen(media_list[i]->name) + 1);
 	}
-	read_unlock_bh(&tipc_net_lock);
 	return buf;
 }
 
@@ -247,7 +217,7 @@
 		return NULL;
 
 	read_lock_bh(&tipc_net_lock);
-	for (i = 0; i < media_count; i++) {
+	for (i = 0; media_list[i] != NULL; i++) {
 		for (j = 0; j < MAX_BEARERS; j++) {
 			b_ptr = &tipc_bearers[j];
 			if (b_ptr->active && (b_ptr->media == media_list[i])) {
@@ -472,5 +442,4 @@
 		if (tipc_bearers[i].active)
 			bearer_disable(&tipc_bearers[i]);
 	}
-	media_count = 0;
 }