Merge tag 'rxrpc-rewrite-20160930' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

David Howells says:

====================
rxrpc: More fixes and adjustments

This set of patches contains some more fixes and adjustments:

 (1) Actually display the retransmission indication previously added to the
     tx_data trace.

 (2) Switch to Congestion Avoidance mode properly at cwnd==ssthresh rather
     than relying on detection during an overshoot and correction.

 (3) Reduce ssthresh to the peer's declared receive window.

 (4) The offset field in rxrpc_skb_priv can be dispensed with and the error
     field is no longer used.  Get rid of them.

 (5) Keep the call timeouts as ktimes rather than jiffies to make it easier
     to deal with RTT-based timeout values in future.  Rounding to jiffies
     is still necessary when the system timer is set.

 (6) Fix the call timer handling to avoid retriggering of expired timeout
     actions.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 19 insertions, 15 deletions

diff --git a/net/rxrpc/input.c b/net/rxrpc/input.c
index 1461d30583c9..3ad9f75031e3 100644
--- a/net/rxrpc/input.c
+++ b/net/rxrpc/input.c
@@ -57,7 +57,7 @@ static void rxrpc_congestion_management(struct rxrpc_call *call,
 		call->cong_ssthresh = max_t(unsigned int,
 					    summary->flight_size / 2, 2);
 		cwnd = 1;
-		if (cwnd > call->cong_ssthresh &&
+		if (cwnd >= call->cong_ssthresh &&
 		    call->cong_mode == RXRPC_CALL_SLOW_START) {
 			call->cong_mode = RXRPC_CALL_CONGEST_AVOIDANCE;
 			call->cong_tstamp = skb->tstamp;
@@ -82,7 +82,7 @@ static void rxrpc_congestion_management(struct rxrpc_call *call,
 			goto packet_loss_detected;
 		if (summary->cumulative_acks > 0)
 			cwnd += 1;
-		if (cwnd > call->cong_ssthresh) {
+		if (cwnd >= call->cong_ssthresh) {
 			call->cong_mode = RXRPC_CALL_CONGEST_AVOIDANCE;
 			call->cong_tstamp = skb->tstamp;
 		}
@@ -161,7 +161,7 @@ resume_normality:
 	call->cong_dup_acks = 0;
 	call->cong_extra = 0;
 	call->cong_tstamp = skb->tstamp;
-	if (cwnd <= call->cong_ssthresh)
+	if (cwnd < call->cong_ssthresh)
 		call->cong_mode = RXRPC_CALL_SLOW_START;
 	else
 		call->cong_mode = RXRPC_CALL_CONGEST_AVOIDANCE;
@@ -328,7 +328,8 @@ static bool rxrpc_receiving_reply(struct rxrpc_call *call)
 		call->resend_at = call->expire_at;
 		call->ack_at = call->expire_at;
 		spin_unlock_bh(&call->lock);
-		rxrpc_set_timer(call, rxrpc_timer_init_for_reply);
+		rxrpc_set_timer(call, rxrpc_timer_init_for_reply,
+				ktime_get_real());
 	}
 
 	if (!test_bit(RXRPC_CALL_TX_LAST, &call->flags))
@@ -358,7 +359,7 @@ static bool rxrpc_receiving_reply(struct rxrpc_call *call)
 static bool rxrpc_validate_jumbo(struct sk_buff *skb)
 {
 	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
-	unsigned int offset = sp->offset;
+	unsigned int offset = sizeof(struct rxrpc_wire_header);
 	unsigned int len = skb->len;
 	int nr_jumbo = 1;
 	u8 flags = sp->hdr.flags;
@@ -419,7 +420,7 @@ static void rxrpc_input_data(struct rxrpc_call *call, struct sk_buff *skb,
 			     u16 skew)
 {
 	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
-	unsigned int offset = sp->offset;
+	unsigned int offset = sizeof(struct rxrpc_wire_header);
 	unsigned int ix;
 	rxrpc_serial_t serial = sp->hdr.serial, ack_serial = 0;
 	rxrpc_seq_t seq = sp->hdr.seq, hard_ack;
@@ -658,6 +659,8 @@ static void rxrpc_input_ackinfo(struct rxrpc_call *call, struct sk_buff *skb,
 	if (rwind > RXRPC_RXTX_BUFF_SIZE - 1)
 		rwind = RXRPC_RXTX_BUFF_SIZE - 1;
 	call->tx_winsize = rwind;
+	if (call->cong_ssthresh > rwind)
+		call->cong_ssthresh = rwind;
 
 	mtu = min(ntohl(ackinfo->rxMTU), ntohl(ackinfo->maxMTU));
 
@@ -744,15 +747,16 @@ static void rxrpc_input_ack(struct rxrpc_call *call, struct sk_buff *skb,
 	} buf;
 	rxrpc_serial_t acked_serial;
 	rxrpc_seq_t first_soft_ack, hard_ack;
-	int nr_acks, offset;
+	int nr_acks, offset, ioffset;
 
 	_enter("");
 
-	if (skb_copy_bits(skb, sp->offset, &buf.ack, sizeof(buf.ack)) < 0) {
+	offset = sizeof(struct rxrpc_wire_header);
+	if (skb_copy_bits(skb, offset, &buf.ack, sizeof(buf.ack)) < 0) {
 		_debug("extraction failure");
 		return rxrpc_proto_abort("XAK", call, 0);
 	}
-	sp->offset += sizeof(buf.ack);
+	offset += sizeof(buf.ack);
 
 	acked_serial = ntohl(buf.ack.serial);
 	first_soft_ack = ntohl(buf.ack.firstPacket);
@@ -790,9 +794,9 @@ static void rxrpc_input_ack(struct rxrpc_call *call, struct sk_buff *skb,
 				  rxrpc_propose_ack_respond_to_ack);
 	}
 
-	offset = sp->offset + nr_acks + 3;
-	if (skb->len >= offset + sizeof(buf.info)) {
-		if (skb_copy_bits(skb, offset, &buf.info, sizeof(buf.info)) < 0)
+	ioffset = offset + nr_acks + 3;
+	if (skb->len >= ioffset + sizeof(buf.info)) {
+		if (skb_copy_bits(skb, ioffset, &buf.info, sizeof(buf.info)) < 0)
 			return rxrpc_proto_abort("XAI", call, 0);
 		rxrpc_input_ackinfo(call, skb, &buf.info);
 	}
@@ -830,7 +834,7 @@ static void rxrpc_input_ack(struct rxrpc_call *call, struct sk_buff *skb,
 		rxrpc_rotate_tx_window(call, hard_ack, &summary);
 
 	if (nr_acks > 0) {
-		if (skb_copy_bits(skb, sp->offset, buf.acks, nr_acks) < 0)
+		if (skb_copy_bits(skb, offset, buf.acks, nr_acks) < 0)
 			return rxrpc_proto_abort("XSA", call, 0);
 		rxrpc_input_soft_acks(call, buf.acks, first_soft_ack, nr_acks,
 				      &summary);
@@ -878,7 +882,8 @@ static void rxrpc_input_abort(struct rxrpc_call *call, struct sk_buff *skb)
 	_enter("");
 
 	if (skb->len >= 4 &&
-	    skb_copy_bits(skb, sp->offset, &wtmp, sizeof(wtmp)) >= 0)
+	    skb_copy_bits(skb, sizeof(struct rxrpc_wire_header),
+			  &wtmp, sizeof(wtmp)) >= 0)
 		abort_code = ntohl(wtmp);
 
 	_proto("Rx ABORT %%%u { %x }", sp->hdr.serial, abort_code);
@@ -994,7 +999,6 @@ int rxrpc_extract_header(struct rxrpc_skb_priv *sp, struct sk_buff *skb)
 	sp->hdr.securityIndex	= whdr.securityIndex;
 	sp->hdr._rsvd		= ntohs(whdr._rsvd);
 	sp->hdr.serviceId	= ntohs(whdr.serviceId);
-	sp->offset = sizeof(whdr);
 	return 0;
 }