Commit 0d967960 authored by David Howells's avatar David Howells
Browse files

rxrpc: Schedule an ACK if the reply to a client call appears overdue 



If we've sent all the request data in a client call but haven't seen any
sign of the reply data yet, schedule an ACK to be sent to the server to
find out if the reply data got lost.

If the server hasn't yet hard-ACK'd the request data, we send a PING ACK to
demand a response to find out whether we need to retransmit.

If the server says it has received all of the data, we send an IDLE ACK to
tell the server that we haven't received anything in the receive phase as
yet.

To make this work, a non-immediate PING ACK must carry a delay.  I've chosen
the same as the IDLE ACK for the moment.

Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
parent 31a1b989

net/rxrpc/ar-internal.h

+2 −0
Original line number Diff line number Diff line
@@ -707,7 +707,9 @@ enum rxrpc_timer_trace { 
extern const char rxrpc_timer_traces[rxrpc_timer__nr_trace][8];



enum rxrpc_propose_ack_trace {

	rxrpc_propose_ack_client_tx_end,

	rxrpc_propose_ack_input_data,

	rxrpc_propose_ack_ping_for_lost_reply,

	rxrpc_propose_ack_ping_for_params,

	rxrpc_propose_ack_respond_to_ack,

	rxrpc_propose_ack_respond_to_ping,

net/rxrpc/call_event.c

+1 −0
Original line number Diff line number Diff line
@@ -100,6 +100,7 @@ static void __rxrpc_propose_ACK(struct rxrpc_call *call, u8 ack_reason, 
			expiry = rxrpc_soft_ack_delay;

		break;



	case RXRPC_ACK_PING:

	case RXRPC_ACK_IDLE:

		if (rxrpc_idle_ack_delay < expiry)

			expiry = rxrpc_idle_ack_delay;

net/rxrpc/input.c

+8 −0
Original line number Diff line number Diff line
@@ -138,6 +138,8 @@ static bool rxrpc_end_tx_phase(struct rxrpc_call *call, bool reply_begun, 


	write_unlock(&call->state_lock);

	if (call->state == RXRPC_CALL_CLIENT_AWAIT_REPLY) {

		rxrpc_propose_ACK(call, RXRPC_ACK_IDLE, 0, 0, false, true,

				  rxrpc_propose_ack_client_tx_end);

		trace_rxrpc_transmit(call, rxrpc_transmit_await_reply);

	} else {

		trace_rxrpc_transmit(call, rxrpc_transmit_end);
@@ -684,6 +686,12 @@ static void rxrpc_input_ack(struct rxrpc_call *call, struct sk_buff *skb, 
		return;

	}



	if (call->rxtx_annotations[call->tx_top & RXRPC_RXTX_BUFF_MASK] &

	    RXRPC_TX_ANNO_LAST &&

	    summary.nr_acks == call->tx_top - hard_ack)

		rxrpc_propose_ACK(call, RXRPC_ACK_PING, skew, sp->hdr.serial,

				  false, true,

				  rxrpc_propose_ack_ping_for_lost_reply);

}



/*

net/rxrpc/misc.c

+2 −0
Original line number Diff line number Diff line
@@ -198,7 +198,9 @@ const char rxrpc_timer_traces[rxrpc_timer__nr_trace][8] = { 
};



const char rxrpc_propose_ack_traces[rxrpc_propose_ack__nr_trace][8] = {

	[rxrpc_propose_ack_client_tx_end]	= "ClTxEnd",

	[rxrpc_propose_ack_input_data]		= "DataIn ",

	[rxrpc_propose_ack_ping_for_lost_reply]	= "LostRpl",

	[rxrpc_propose_ack_ping_for_params]	= "Params ",

	[rxrpc_propose_ack_respond_to_ack]	= "Rsp2Ack",

	[rxrpc_propose_ack_respond_to_ping]	= "Rsp2Png",

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