tipc: extract bundled buffers by cloning instead of copying
When we currently extract a bundled buffer from a message bundle in
the function tipc_msg_extract(), we allocate a new buffer and explicitly
copy the linear data area.
This is unnecessary, since we can just clone the buffer and do
skb_pull() on the clone to move the data pointer to the correct
position.
This is what we do in this commit.
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-by: Ying Xue <ying.xue@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/link.c b/net/tipc/link.c
index 8c6639d..56c39b1 100644
--- a/net/tipc/link.c
+++ b/net/tipc/link.c
@@ -1,7 +1,7 @@
/*
* net/tipc/link.c: TIPC link code
*
- * Copyright (c) 1996-2007, 2012-2014, Ericsson AB
+ * Copyright (c) 1996-2007, 2012-2015, Ericsson AB
* Copyright (c) 2004-2007, 2010-2013, Wind River Systems
* All rights reserved.
*
@@ -1117,7 +1117,7 @@
ackd = msg_ack(msg);
/* Release acked messages */
- if (n_ptr->bclink.recv_permitted)
+ if (likely(n_ptr->bclink.recv_permitted))
tipc_bclink_acknowledge(n_ptr, msg_bcast_ack(msg));
released = 0;
@@ -1712,45 +1712,24 @@
}
}
-/**
- * buf_extract - extracts embedded TIPC message from another message
- * @skb: encapsulating message buffer
- * @from_pos: offset to extract from
- *
- * Returns a new message buffer containing an embedded message. The
- * encapsulating buffer is left unchanged.
- */
-static struct sk_buff *buf_extract(struct sk_buff *skb, u32 from_pos)
-{
- struct tipc_msg *msg = (struct tipc_msg *)(skb->data + from_pos);
- u32 size = msg_size(msg);
- struct sk_buff *eb;
-
- eb = tipc_buf_acquire(size);
- if (eb)
- skb_copy_to_linear_data(eb, msg, size);
- return eb;
-}
-
/* tipc_link_dup_rcv(): Receive a tunnelled DUPLICATE_MSG packet.
* Owner node is locked.
*/
-static void tipc_link_dup_rcv(struct tipc_link *l_ptr,
- struct sk_buff *t_buf)
+static void tipc_link_dup_rcv(struct tipc_link *link,
+ struct sk_buff *skb)
{
- struct sk_buff *buf;
+ struct sk_buff *iskb;
+ int pos = 0;
- if (!tipc_link_is_up(l_ptr))
+ if (!tipc_link_is_up(link))
return;
- buf = buf_extract(t_buf, INT_H_SIZE);
- if (buf == NULL) {
+ if (!tipc_msg_extract(skb, &iskb, &pos)) {
pr_warn("%sfailed to extract inner dup pkt\n", link_co_err);
return;
}
-
- /* Add buffer to deferred queue, if applicable: */
- link_handle_out_of_seq_msg(l_ptr, buf);
+ /* Append buffer to deferred queue, if applicable: */
+ link_handle_out_of_seq_msg(link, iskb);
}
/* tipc_link_failover_rcv(): Receive a tunnelled ORIGINAL_MSG packet
@@ -1762,6 +1741,7 @@
struct tipc_msg *t_msg = buf_msg(t_buf);
struct sk_buff *buf = NULL;
struct tipc_msg *msg;
+ int pos = 0;
if (tipc_link_is_up(l_ptr))
tipc_link_reset(l_ptr);
@@ -1773,8 +1753,7 @@
/* Should there be an inner packet? */
if (l_ptr->exp_msg_count) {
l_ptr->exp_msg_count--;
- buf = buf_extract(t_buf, INT_H_SIZE);
- if (buf == NULL) {
+ if (!tipc_msg_extract(t_buf, &buf, &pos)) {
pr_warn("%sno inner failover pkt\n", link_co_err);
goto exit;
}