tipc: Fix port counter handling to correct congestion control
Modifies TIPC's congestion control between a connected port and its
peer so that it works as documented. The following changes have been
made:
1) The counter of the number of messages sent by a port now starts
at zero, rather than one. This prevents the port from reporting port
congestion one message earlier than it was supposed to.
2) The counter of the number of messages sent by a port is now
incremented only if a non-empty message is sent successfully.
This prevents the port from becoming permanently congested if
too many send attempts are unsuccessful because of congestion
(or other reasons). It also removes the risk that empty hand-
shaking messages used during connection setup might cause the
port to report congestion earlier than it was supposed to.
3) The counter of the number of unacknowledged messages received by
a port controlled by an internal TIPC service is now incremented
only if the message is non-empty, in order to be consistent with
the aforementioned changes.
Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
diff --git a/net/tipc/port.c b/net/tipc/port.c
index aff5dc0..3e5122c 100644
--- a/net/tipc/port.c
+++ b/net/tipc/port.c
@@ -234,7 +234,6 @@
tipc_msg_init(msg, importance, TIPC_NAMED_MSG, LONG_H_SIZE, 0);
msg_set_origport(msg, ref);
p_ptr->last_in_seqno = 41;
- p_ptr->sent = 1;
INIT_LIST_HEAD(&p_ptr->wait_list);
INIT_LIST_HEAD(&p_ptr->subscription.nodesub_list);
p_ptr->dispatcher = dispatcher;
@@ -732,6 +731,7 @@
tipc_conn_msg_event cb = up_ptr->conn_msg_cb;
u32 peer_port = port_peerport(p_ptr);
u32 peer_node = port_peernode(p_ptr);
+ u32 dsz;
tipc_port_unlock(p_ptr);
if (unlikely(!cb))
@@ -742,13 +742,14 @@
} else if ((msg_origport(msg) != peer_port) ||
(msg_orignode(msg) != peer_node))
goto reject;
- if (unlikely(++p_ptr->conn_unacked >=
- TIPC_FLOW_CONTROL_WIN))
+ dsz = msg_data_sz(msg);
+ if (unlikely(dsz &&
+ (++p_ptr->conn_unacked >=
+ TIPC_FLOW_CONTROL_WIN)))
tipc_acknowledge(dref,
p_ptr->conn_unacked);
skb_pull(buf, msg_hdr_sz(msg));
- cb(usr_handle, dref, &buf, msg_data(msg),
- msg_data_sz(msg));
+ cb(usr_handle, dref, &buf, msg_data(msg), dsz);
break;
}
case TIPC_DIRECT_MSG:{
@@ -1221,7 +1222,8 @@
if (likely(res != -ELINKCONG)) {
port_incr_out_seqno(p_ptr);
p_ptr->congested = 0;
- p_ptr->sent++;
+ if (res > 0)
+ p_ptr->sent++;
return res;
}
}
@@ -1263,13 +1265,17 @@
msg_set_destport(msg, destport);
if (likely(destport)) {
- p_ptr->sent++;
if (likely(destnode == tipc_own_addr))
- return tipc_port_recv_sections(p_ptr, num_sect, msg_sect);
- res = tipc_link_send_sections_fast(p_ptr, msg_sect, num_sect,
- destnode);
- if (likely(res != -ELINKCONG))
+ res = tipc_port_recv_sections(p_ptr, num_sect,
+ msg_sect);
+ else
+ res = tipc_link_send_sections_fast(p_ptr, msg_sect,
+ num_sect, destnode);
+ if (likely(res != -ELINKCONG)) {
+ if (res > 0)
+ p_ptr->sent++;
return res;
+ }
if (port_unreliable(p_ptr)) {
/* Just calculate msg length and return */
return tipc_msg_calc_data_size(msg_sect, num_sect);
@@ -1302,12 +1308,17 @@
msg_set_destnode(msg, dest->node);
msg_set_destport(msg, dest->ref);
msg_set_hdr_sz(msg, DIR_MSG_H_SIZE);
- p_ptr->sent++;
+
if (dest->node == tipc_own_addr)
- return tipc_port_recv_sections(p_ptr, num_sect, msg_sect);
- res = tipc_link_send_sections_fast(p_ptr, msg_sect, num_sect, dest->node);
- if (likely(res != -ELINKCONG))
+ res = tipc_port_recv_sections(p_ptr, num_sect, msg_sect);
+ else
+ res = tipc_link_send_sections_fast(p_ptr, msg_sect, num_sect,
+ dest->node);
+ if (likely(res != -ELINKCONG)) {
+ if (res > 0)
+ p_ptr->sent++;
return res;
+ }
if (port_unreliable(p_ptr)) {
/* Just calculate msg length and return */
return tipc_msg_calc_data_size(msg_sect, num_sect);
@@ -1343,12 +1354,16 @@
skb_push(buf, DIR_MSG_H_SIZE);
skb_copy_to_linear_data(buf, msg, DIR_MSG_H_SIZE);
- p_ptr->sent++;
+
if (dest->node == tipc_own_addr)
- return tipc_port_recv_msg(buf);
- res = tipc_send_buf_fast(buf, dest->node);
- if (likely(res != -ELINKCONG))
+ res = tipc_port_recv_msg(buf);
+ else
+ res = tipc_send_buf_fast(buf, dest->node);
+ if (likely(res != -ELINKCONG)) {
+ if (res > 0)
+ p_ptr->sent++;
return res;
+ }
if (port_unreliable(p_ptr))
return dsz;
return -ELINKCONG;