Commit 547a9acd authored by David Howells's avatar David Howells Committed by Jakub Kicinski
Browse files

rxrpc: Tidy up the ACK parsing a bit 



Tidy up the ACK parsing in the following ways:

 (1) Put the serial number of the ACK packet into the rxrpc_ack_summary
     struct and access it from there whilst parsing an ACK.

 (2) Be consistent about using "if (summary.acked_serial)" rather than "if
     (summary.acked_serial != 0)".

Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent a2ea9a90

net/rxrpc/ar-internal.h

+1 −0
Original line number Diff line number Diff line
@@ -771,6 +771,7 @@ struct rxrpc_call { 
 * Summary of a new ACK and the changes it made to the Tx buffer packet states.

 */

struct rxrpc_ack_summary {

	rxrpc_serial_t	ack_serial;		/* Serial number of ACK */

	rxrpc_serial_t	acked_serial;		/* Serial number ACK'd */

	u16		in_flight;		/* Number of unreceived transmissions */

	u16		nr_new_hacks;		/* Number of rotated new ACKs */

net/rxrpc/input.c

+26 −29
Original line number Diff line number Diff line
@@ -198,11 +198,10 @@ void rxrpc_congestion_degrade(struct rxrpc_call *call) 
static void rxrpc_add_data_rtt_sample(struct rxrpc_call *call,

				      struct rxrpc_ack_summary *summary,

				      struct rxrpc_txqueue *tq,

				      int ix,

				      rxrpc_serial_t ack_serial)

				      int ix)

{

	rxrpc_peer_add_rtt(call, rxrpc_rtt_rx_data_ack, -1,

			   summary->acked_serial, ack_serial,

			   summary->acked_serial, summary->ack_serial,

			   ktime_add_us(tq->xmit_ts_base, tq->segment_xmit_ts[ix]),

			   call->acks_latest_ts);

	summary->rtt_sample_avail = false;
@@ -213,8 +212,7 @@ static void rxrpc_add_data_rtt_sample(struct rxrpc_call *call, 
 * Apply a hard ACK by advancing the Tx window.

 */

static bool rxrpc_rotate_tx_window(struct rxrpc_call *call, rxrpc_seq_t to,

				   struct rxrpc_ack_summary *summary,

				   rxrpc_serial_t ack_serial)

				   struct rxrpc_ack_summary *summary)

{

	struct rxrpc_txqueue *tq = call->tx_queue;

	rxrpc_seq_t seq = call->tx_bottom + 1;
@@ -255,7 +253,7 @@ static bool rxrpc_rotate_tx_window(struct rxrpc_call *call, rxrpc_seq_t to, 
		if (summary->rtt_sample_avail &&

		    summary->acked_serial == tq->segment_serial[ix] &&

		    test_bit(ix, &tq->rtt_samples))

			rxrpc_add_data_rtt_sample(call, summary, tq, ix, ack_serial);

			rxrpc_add_data_rtt_sample(call, summary, tq, ix);



		if (ix == tq->nr_reported_acks) {

			/* Packet directly hard ACK'd. */
@@ -369,7 +367,7 @@ static bool rxrpc_receiving_reply(struct rxrpc_call *call) 
	}



	if (!test_bit(RXRPC_CALL_TX_LAST, &call->flags)) {

		if (!rxrpc_rotate_tx_window(call, top, &summary, 0)) {

		if (!rxrpc_rotate_tx_window(call, top, &summary)) {

			rxrpc_proto_abort(call, top, rxrpc_eproto_early_reply);

			return false;

		}
@@ -826,12 +824,11 @@ static void rxrpc_input_ack_trailer(struct rxrpc_call *call, struct sk_buff *skb 
 */

static void rxrpc_input_soft_rtt(struct rxrpc_call *call,

				 struct rxrpc_ack_summary *summary,

				 struct rxrpc_txqueue *tq,

				 rxrpc_serial_t ack_serial)

				 struct rxrpc_txqueue *tq)

{

	for (int ix = 0; ix < RXRPC_NR_TXQUEUE; ix++)

		if (summary->acked_serial == tq->segment_serial[ix])

			return rxrpc_add_data_rtt_sample(call, summary, tq, ix, ack_serial);

			return rxrpc_add_data_rtt_sample(call, summary, tq, ix);

}



/*
@@ -944,7 +941,7 @@ static void rxrpc_input_soft_acks(struct rxrpc_call *call, 
		_debug("bound %16lx %u", extracted, nr);



		if (summary->rtt_sample_avail)

			rxrpc_input_soft_rtt(call, summary, tq, sp->hdr.serial);

			rxrpc_input_soft_rtt(call, summary, tq);

		rxrpc_input_soft_ack_tq(call, summary, tq, extracted, RXRPC_NR_TXQUEUE,

					seq - RXRPC_NR_TXQUEUE, &lowest_nak);

		extracted = ~0UL;
@@ -1016,7 +1013,6 @@ static void rxrpc_input_ack(struct rxrpc_call *call, struct sk_buff *skb) 
	struct rxrpc_ack_summary summary = { 0 };

	struct rxrpc_acktrailer trailer;

	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);

	rxrpc_serial_t ack_serial;

	rxrpc_seq_t first_soft_ack, hard_ack, prev_pkt;

	int nr_acks, offset, ioffset;
@@ -1024,7 +1020,7 @@ static void rxrpc_input_ack(struct rxrpc_call *call, struct sk_buff *skb) 


	offset = sizeof(struct rxrpc_wire_header) + sizeof(struct rxrpc_ackpacket);



	ack_serial	= sp->hdr.serial;

	summary.ack_serial	= sp->hdr.serial;

	first_soft_ack		= sp->ack.first_ack;

	prev_pkt		= sp->ack.prev_ack;

	nr_acks			= sp->ack.nr_acks;
@@ -1066,7 +1062,7 @@ static void rxrpc_input_ack(struct rxrpc_call *call, struct sk_buff *skb) 


	/* Discard any out-of-order or duplicate ACKs (outside lock). */

	if (!rxrpc_is_ack_valid(call, hard_ack, prev_pkt)) {

		trace_rxrpc_rx_discard_ack(call, ack_serial, hard_ack, prev_pkt);

		trace_rxrpc_rx_discard_ack(call, summary.ack_serial, hard_ack, prev_pkt);

		goto send_response;

	}
@@ -1100,10 +1096,10 @@ static void rxrpc_input_ack(struct rxrpc_call *call, struct sk_buff *skb) 
	if (hard_ack + 1 == 0)

		return rxrpc_proto_abort(call, 0, rxrpc_eproto_ackr_zero);



	if (summary.acked_serial != 0) {

	if (summary.acked_serial) {

		if (summary.ack_reason == RXRPC_ACK_PING_RESPONSE)

			rxrpc_complete_rtt_probe(call, call->acks_latest_ts,

						 summary.acked_serial, ack_serial,

						 summary.acked_serial, summary.ack_serial,

						 rxrpc_rtt_rx_ping_response);

		else

			summary.rtt_sample_avail = true;
@@ -1127,7 +1123,7 @@ static void rxrpc_input_ack(struct rxrpc_call *call, struct sk_buff *skb) 
		return rxrpc_proto_abort(call, 0, rxrpc_eproto_ackr_sack_overflow);



	if (after(hard_ack, call->tx_bottom)) {

		if (rxrpc_rotate_tx_window(call, hard_ack, &summary, ack_serial)) {

		if (rxrpc_rotate_tx_window(call, hard_ack, &summary)) {

			rxrpc_end_tx_phase(call, false, rxrpc_eproto_unexpected_ack);

			goto send_response;

		}
@@ -1142,19 +1138,20 @@ static void rxrpc_input_ack(struct rxrpc_call *call, struct sk_buff *skb) 
	if (test_bit(RXRPC_CALL_TX_LAST, &call->flags) &&

	    call->acks_nr_sacks == call->tx_top - hard_ack &&

	    rxrpc_is_client_call(call))

		rxrpc_propose_ping(call, ack_serial,

		rxrpc_propose_ping(call, summary.ack_serial,

				   rxrpc_propose_ack_ping_for_lost_reply);



	rxrpc_congestion_management(call, &summary);

	if (summary.need_retransmit)

		rxrpc_resend(call, ack_serial, summary.ack_reason == RXRPC_ACK_PING_RESPONSE);

		rxrpc_resend(call, summary.ack_serial,

			     summary.ack_reason == RXRPC_ACK_PING_RESPONSE);



send_response:

	if (summary.ack_reason == RXRPC_ACK_PING)

		rxrpc_send_ACK(call, RXRPC_ACK_PING_RESPONSE, ack_serial,

		rxrpc_send_ACK(call, RXRPC_ACK_PING_RESPONSE, summary.ack_serial,

			       rxrpc_propose_ack_respond_to_ping);

	else if (sp->hdr.flags & RXRPC_REQUEST_ACK)

		rxrpc_send_ACK(call, RXRPC_ACK_REQUESTED, ack_serial,

		rxrpc_send_ACK(call, RXRPC_ACK_REQUESTED, summary.ack_serial,

			       rxrpc_propose_ack_respond_to_ack);

}
@@ -1165,7 +1162,7 @@ static void rxrpc_input_ackall(struct rxrpc_call *call, struct sk_buff *skb) 
{

	struct rxrpc_ack_summary summary = { 0 };



	if (rxrpc_rotate_tx_window(call, call->tx_top, &summary, 0))

	if (rxrpc_rotate_tx_window(call, call->tx_top, &summary))

		rxrpc_end_tx_phase(call, false, rxrpc_eproto_unexpected_ackall);

}