From a7056c5ba67ee6a956b42cf9ff9ba3a6a0bd9794 Mon Sep 17 00:00:00 2001 From: David Howells Date: Sat, 24 Sep 2016 18:05:27 +0100 Subject: rxrpc: Send an immediate ACK if we fill in a hole Send an immediate ACK if we fill in a hole in the buffer left by an out-of-sequence packet. This may allow the congestion management in the peer to avoid a retransmission if packets got reordered on the wire. Signed-off-by: David Howells --- net/rxrpc/input.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) (limited to 'net') diff --git a/net/rxrpc/input.c b/net/rxrpc/input.c index 349698d87ad1..757c16f033a0 100644 --- a/net/rxrpc/input.c +++ b/net/rxrpc/input.c @@ -331,8 +331,16 @@ next_subpacket: call->rxtx_annotations[ix] = annotation; smp_wmb(); call->rxtx_buffer[ix] = skb; - if (after(seq, call->rx_top)) + if (after(seq, call->rx_top)) { smp_store_release(&call->rx_top, seq); + } else if (before(seq, call->rx_top)) { + /* Send an immediate ACK if we fill in a hole */ + if (!ack) { + ack = RXRPC_ACK_DELAY; + ack_serial = serial; + } + immediate_ack = true; + } if (flags & RXRPC_LAST_PACKET) { set_bit(RXRPC_CALL_RX_LAST, &call->flags); trace_rxrpc_receive(call, rxrpc_receive_queue_last, serial, seq); -- cgit v1.2.3-55-g7522