Commit 8637abaa authored Nov 24, 2017 by David Howells

rxrpc: Don't transmit DELAY ACKs immediately on proposal



Don't transmit a DELAY ACK immediately on proposal when the Rx window is
rotated, but rather defer it to the work function.  This means that we have
a chance to queue/consume more received packets before we actually send the
DELAY ACK, or even cancel it entirely, thereby reducing the number of
packets transmitted.

We do, however, want to continue sending other types of packet immediately,
particularly REQUESTED ACKs, as they may be used for RTT calculation by the
other side.

Signed-off-by: David Howells <dhowells@redhat.com>

parent a158bdd3

net/rxrpc/recvmsg.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -219,9 +219,9 @@ static void rxrpc_rotate_rx_window(struct rxrpc_call *call)
		after_eq(top, call->ackr_seen + 2) \|\|
		(hard_ack == top && after(hard_ack, call->ackr_consumed)))
		rxrpc_propose_ACK(call, RXRPC_ACK_DELAY, 0, serial,
		true, false,
		true, true,
		rxrpc_propose_ack_rotate_rx);
		if (call->ackr_reason)
		if (call->ackr_reason && call->ackr_reason != RXRPC_ACK_DELAY)
		rxrpc_send_ack_packet(call, false);
		}
		}

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