From: David Howells Date: Mon, 23 Jul 2018 16:18:37 +0000 (+0100) Subject: rxrpc: Propose, but don't immediately transmit, the final ACK for a call X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=a71a2651bdd3ad9ccae7d8e8c6782727c7ecba98;p=linux.git rxrpc: Propose, but don't immediately transmit, the final ACK for a call The final ACK that closes out an rxrpc call needs to be transmitted by the client unless we're going to follow up with a DATA packet for a new call on the same channel (which implicitly ACK's the previous call, thereby saving an ACK). Currently, we don't do that, so if no follow on call is immediately forthcoming, the server will resend the last DATA packet - at which point rxrpc_conn_retransmit_call() will be triggered and will (re)send the final ACK. But the server has to hold on to the last packet until the ACK is received, thereby holding up its resources. Fix the client side to propose a delayed final ACK, to be transmitted after a short delay, assuming the call isn't superseded by a new one. Signed-off-by: David Howells --- diff --git a/net/rxrpc/recvmsg.c b/net/rxrpc/recvmsg.c index 7bff716e911ea..02f1f768e16a7 100644 --- a/net/rxrpc/recvmsg.c +++ b/net/rxrpc/recvmsg.c @@ -144,13 +144,11 @@ static void rxrpc_end_rx_phase(struct rxrpc_call *call, rxrpc_serial_t serial) trace_rxrpc_receive(call, rxrpc_receive_end, 0, call->rx_top); ASSERTCMP(call->rx_hard_ack, ==, call->rx_top); -#if 0 // TODO: May want to transmit final ACK under some circumstances anyway if (call->state == RXRPC_CALL_CLIENT_RECV_REPLY) { - rxrpc_propose_ACK(call, RXRPC_ACK_IDLE, 0, serial, true, false, + rxrpc_propose_ACK(call, RXRPC_ACK_IDLE, 0, serial, false, true, rxrpc_propose_ack_terminal_ack); - rxrpc_send_ack_packet(call, false, NULL); + //rxrpc_send_ack_packet(call, false, NULL); } -#endif write_lock_bh(&call->state_lock);