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-rw-r--r--net/tipc/socket.c48
1 files changed, 1 insertions, 47 deletions
diff --git a/net/tipc/socket.c b/net/tipc/socket.c
index 22d92f0ec5ac..4916d8fea328 100644
--- a/net/tipc/socket.c
+++ b/net/tipc/socket.c
@@ -1,7 +1,7 @@
/*
* net/tipc/socket.c: TIPC socket API
*
- * Copyright (c) 2001-2007, 2012-2015, Ericsson AB
+ * Copyright (c) 2001-2007, 2012-2016, Ericsson AB
* Copyright (c) 2004-2008, 2010-2013, Wind River Systems
* All rights reserved.
*
@@ -127,54 +127,8 @@ static const struct proto_ops packet_ops;
static const struct proto_ops stream_ops;
static const struct proto_ops msg_ops;
static struct proto tipc_proto;
-
static const struct rhashtable_params tsk_rht_params;
-/*
- * Revised TIPC socket locking policy:
- *
- * Most socket operations take the standard socket lock when they start
- * and hold it until they finish (or until they need to sleep). Acquiring
- * this lock grants the owner exclusive access to the fields of the socket
- * data structures, with the exception of the backlog queue. A few socket
- * operations can be done without taking the socket lock because they only
- * read socket information that never changes during the life of the socket.
- *
- * Socket operations may acquire the lock for the associated TIPC port if they
- * need to perform an operation on the port. If any routine needs to acquire
- * both the socket lock and the port lock it must take the socket lock first
- * to avoid the risk of deadlock.
- *
- * The dispatcher handling incoming messages cannot grab the socket lock in
- * the standard fashion, since invoked it runs at the BH level and cannot block.
- * Instead, it checks to see if the socket lock is currently owned by someone,
- * and either handles the message itself or adds it to the socket's backlog
- * queue; in the latter case the queued message is processed once the process
- * owning the socket lock releases it.
- *
- * NOTE: Releasing the socket lock while an operation is sleeping overcomes
- * the problem of a blocked socket operation preventing any other operations
- * from occurring. However, applications must be careful if they have
- * multiple threads trying to send (or receive) on the same socket, as these
- * operations might interfere with each other. For example, doing a connect
- * and a receive at the same time might allow the receive to consume the
- * ACK message meant for the connect. While additional work could be done
- * to try and overcome this, it doesn't seem to be worthwhile at the present.
- *
- * NOTE: Releasing the socket lock while an operation is sleeping also ensures
- * that another operation that must be performed in a non-blocking manner is
- * not delayed for very long because the lock has already been taken.
- *
- * NOTE: This code assumes that certain fields of a port/socket pair are
- * constant over its lifetime; such fields can be examined without taking
- * the socket lock and/or port lock, and do not need to be re-read even
- * after resuming processing after waiting. These fields include:
- * - socket type
- * - pointer to socket sk structure (aka tipc_sock structure)
- * - pointer to port structure
- * - port reference
- */
-
static u32 tsk_own_node(struct tipc_sock *tsk)
{
return msg_prevnode(&tsk->phdr);