tipc: remove bearer_lock from tipc_bearer struct
After the earlier commits ("tipc: remove 'links' list from
tipc_bearer struct") and ("tipc: introduce new spinlock to protect
struct link_req"), there is no longer any need to protect struct
link_req or or any link list by use of bearer_lock. Furthermore,
we have eliminated the need for using bearer_lock during downcalls
(send) from the link to the bearer, since we have ensured that
bearers always have a longer life cycle that their associated links,
and always contain valid data.
So, the only need now for a lock protecting bearers is for guaranteeing
consistency of the bearer list itself. For this, it is sufficient, at
least for the time being, to continue applying 'net_lock´ in write mode.
By removing bearer_lock we also pre-empt introduction of issue b) descibed
in the previous commit "tipc: remove 'links' list from tipc_bearer struct":
"b) When the outer protection from net_lock is gone, taking
bearer_lock and node_lock in opposite order of method 1) and 2)
will become an obvious deadlock hazard".
Therefore, we now eliminate the bearer_lock spinlock.
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>
diff --git a/net/tipc/bearer.h b/net/tipc/bearer.h
index 647cb1d..425dd81 100644
--- a/net/tipc/bearer.h
+++ b/net/tipc/bearer.h
@@ -107,10 +107,8 @@
/**
* struct tipc_bearer - Generic TIPC bearer structure
- * @dev: ptr to associated network device
- * @usr_handle: pointer to additional media-specific information about bearer
+ * @media_ptr: pointer to additional media-specific information about bearer
* @mtu: max packet size bearer can support
- * @lock: spinlock for controlling access to bearer
* @addr: media-specific address associated with bearer
* @name: bearer name (format = media:interface)
* @media: ptr to media structure associated with bearer
@@ -133,7 +131,6 @@
u32 mtu; /* initalized by media */
struct tipc_media_addr addr; /* initalized by media */
char name[TIPC_MAX_BEARER_NAME];
- spinlock_t lock;
struct tipc_media *media;
struct tipc_media_addr bcast_addr;
u32 priority;