sergiotarxz/nuttx
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

net/tcp: Minor design improvement to TCP delayed ACKs.

Browse Source
This commit is contained in:
Gregory Nutt 2019-12-08 14:17:55 -06:00
parent 66ef6d143a
commit 8cd5e04d53
1 changed files with 9 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

21
net/tcp/tcp_appsend.c
View File

@ -101,9 +101,13 @@ void tcp_appsend(FAR struct net_driver_s *dev, FAR struct tcp_conn_s *conn,
/* Per RFC 1122: "...there SHOULD be an ACK for at least every second /* Per RFC 1122: "...there SHOULD be an ACK for at least every second
* segment." * segment."
*
* NOTE: If there is a data payload or other flags to be sent with the
* outgoing packet, then we may as well include the ACK too.
*/ */
if (conn->rx_unackseg > 0) if (conn->rx_unackseg > 0 || dev->d_sndlen > 0 ||
result != TCP_SNDACK)
{ {
/* Reset the delayed ACK state and send the ACK with this packet. */ /* Reset the delayed ACK state and send the ACK with this packet. */
@ -111,20 +115,13 @@ void tcp_appsend(FAR struct net_driver_s *dev, FAR struct tcp_conn_s *conn,
} }
else else
{ {
/* Indicate that there is one un-ACKed segment and don't send the /* This is only an ACK and there is no pending delayed ACK and
* ACK on this pack. * no TX data is being sent. Indicate that there is one un-ACKed
* segment and don't send anything now.
*/ */
result &= ~TCP_SNDACK;
conn->rx_unackseg = 1; conn->rx_unackseg = 1;
return;
/* A special case is if there are not other flags and no TCP TX
* data payload. In this case, don't send anything.*/
if (result == 0 && dev->d_sndlen == 0)
{
return;
}
} }
} }
#endif #endif