[CONNECTOR]: Use netlink_has_listeners() to avoind unnecessary allocations.

Return -ESRCH from cn_netlink_send() when there are not listeners,
just as it could be done by netlink_broadcast().  Propagate
netlink_broadcast() error back to the caller.

Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 3 insertions, 2 deletions

diff --git a/Documentation/connector/connector.txt b/Documentation/connector/connector.txt
index 57a314b14cf8..ad6e0ba7b38c 100644
--- a/Documentation/connector/connector.txt
+++ b/Documentation/connector/connector.txt
@@ -69,10 +69,11 @@ Unregisters new callback with connector core.
 
 struct cb_id *id                - unique connector's user identifier.
 
-void cn_netlink_send(struct cn_msg *msg, u32 __groups, int gfp_mask);
+int cn_netlink_send(struct cn_msg *msg, u32 __groups, int gfp_mask);
 
 Sends message to the specified groups.  It can be safely called from
-any context, but may silently fail under strong memory pressure.
+softirq context, but may silently fail under strong memory pressure.
+If there are no listeners for given group -ESRCH can be returned.
 
 struct cn_msg *                 - message header(with attached data).
 u32 __group                     - destination group.