Merge tag 'rxrpc-next-20230208' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

David Howells says:

====================
rxrpc development

Here are some miscellaneous changes for rxrpc:

 (1) Use consume_skb() rather than kfree_skb_reason().

 (2) Fix unnecessary waking when poking and already-poked call.

 (3) Add ack.rwind to the rxrpc_tx_ack tracepoint as this indicates how
     many incoming DATA packets we're telling the peer that we are
     currently willing to accept on this call.

 (4) Reduce duplicate ACK transmission.  We send ACKs to let the peer know
     that we're increasing the receive window (ack.rwind) as we consume
     packets locally.  Normal ACK transmission is triggered in three places
     and that leads to duplicates being sent.
====================

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

5 files changed, 15 insertions, 9 deletions

diff --git a/net/rxrpc/call_object.c b/net/rxrpc/call_object.c
index 6eaffb0d8fdc..e9f1f49d18c2 100644
--- a/net/rxrpc/call_object.c
+++ b/net/rxrpc/call_object.c
@@ -54,12 +54,14 @@ void rxrpc_poke_call(struct rxrpc_call *call, enum rxrpc_call_poke_trace what)
 		spin_lock_bh(&local->lock);
 		busy = !list_empty(&call->attend_link);
 		trace_rxrpc_poke_call(call, busy, what);
+		if (!busy && !rxrpc_try_get_call(call, rxrpc_call_get_poke))
+			busy = true;
 		if (!busy) {
-			rxrpc_get_call(call, rxrpc_call_get_poke);
 			list_add_tail(&call->attend_link, &local->call_attend_q);
 		}
 		spin_unlock_bh(&local->lock);
-		rxrpc_wake_up_io_thread(local);
+		if (!busy)
+			rxrpc_wake_up_io_thread(local);
 	}
 }
 
diff --git a/net/rxrpc/conn_event.c b/net/rxrpc/conn_event.c
index 44414e724415..95f4bc206b3d 100644
--- a/net/rxrpc/conn_event.c
+++ b/net/rxrpc/conn_event.c
@@ -163,7 +163,7 @@ void rxrpc_conn_retransmit_call(struct rxrpc_connection *conn,
 		trace_rxrpc_tx_ack(chan->call_debug_id, serial,
 				   ntohl(pkt.ack.firstPacket),
 				   ntohl(pkt.ack.serial),
-				   pkt.ack.reason, 0);
+				   pkt.ack.reason, 0, rxrpc_rx_window_size);
 		break;
 
 	default:
diff --git a/net/rxrpc/output.c b/net/rxrpc/output.c
index 6b2022240076..5e53429c6922 100644
--- a/net/rxrpc/output.c
+++ b/net/rxrpc/output.c
@@ -80,7 +80,8 @@ static void rxrpc_set_keepalive(struct rxrpc_call *call)
  */
 static size_t rxrpc_fill_out_ack(struct rxrpc_connection *conn,
 				 struct rxrpc_call *call,
-				 struct rxrpc_txbuf *txb)
+				 struct rxrpc_txbuf *txb,
+				 u16 *_rwind)
 {
 	struct rxrpc_ackinfo ackinfo;
 	unsigned int qsize, sack, wrap, to;
@@ -124,6 +125,7 @@ static size_t rxrpc_fill_out_ack(struct rxrpc_connection *conn,
 	jmax = rxrpc_rx_jumbo_max;
 	qsize = (window - 1) - call->rx_consumed;
 	rsize = max_t(int, call->rx_winsize - qsize, 0);
+	*_rwind = rsize;
 	ackinfo.rxMTU		= htonl(rxrpc_rx_mtu);
 	ackinfo.maxMTU		= htonl(mtu);
 	ackinfo.rwind		= htonl(rsize);
@@ -190,6 +192,7 @@ int rxrpc_send_ack_packet(struct rxrpc_call *call, struct rxrpc_txbuf *txb)
 	rxrpc_serial_t serial;
 	size_t len, n;
 	int ret, rtt_slot = -1;
+	u16 rwind;
 
 	if (test_bit(RXRPC_CALL_DISCONNECTED, &call->flags))
 		return -ECONNRESET;
@@ -205,7 +208,7 @@ int rxrpc_send_ack_packet(struct rxrpc_call *call, struct rxrpc_txbuf *txb)
 	if (txb->ack.reason == RXRPC_ACK_PING)
 		txb->wire.flags |= RXRPC_REQUEST_ACK;
 
-	n = rxrpc_fill_out_ack(conn, call, txb);
+	n = rxrpc_fill_out_ack(conn, call, txb, &rwind);
 	if (n == 0)
 		return 0;
 
@@ -217,7 +220,8 @@ int rxrpc_send_ack_packet(struct rxrpc_call *call, struct rxrpc_txbuf *txb)
 	txb->wire.serial = htonl(serial);
 	trace_rxrpc_tx_ack(call->debug_id, serial,
 			   ntohl(txb->ack.firstPacket),
-			   ntohl(txb->ack.serial), txb->ack.reason, txb->ack.nAcks);
+			   ntohl(txb->ack.serial), txb->ack.reason, txb->ack.nAcks,
+			   rwind);
 
 	if (txb->ack.reason == RXRPC_ACK_PING)
 		rtt_slot = rxrpc_begin_rtt_probe(call, serial, rxrpc_rtt_tx_ping);
diff --git a/net/rxrpc/recvmsg.c b/net/rxrpc/recvmsg.c
index 50d263a6359d..76eb2b9cd936 100644
--- a/net/rxrpc/recvmsg.c
+++ b/net/rxrpc/recvmsg.c
@@ -137,7 +137,7 @@ static void rxrpc_rotate_rx_window(struct rxrpc_call *call)
 	/* Check to see if there's an ACK that needs sending. */
 	acked = atomic_add_return(call->rx_consumed - old_consumed,
 				  &call->ackr_nr_consumed);
-	if (acked > 2 &&
+	if (acked > 8 &&
 	    !test_and_set_bit(RXRPC_CALL_RX_IS_IDLE, &call->flags))
 		rxrpc_poke_call(call, rxrpc_call_poke_idle);
 }
diff --git a/net/rxrpc/skbuff.c b/net/rxrpc/skbuff.c
index 944320e65ea8..3bcd6ee80396 100644
--- a/net/rxrpc/skbuff.c
+++ b/net/rxrpc/skbuff.c
@@ -63,7 +63,7 @@ void rxrpc_free_skb(struct sk_buff *skb, enum rxrpc_skb_trace why)
 	if (skb) {
 		int n = atomic_dec_return(select_skb_count(skb));
 		trace_rxrpc_skb(skb, refcount_read(&skb->users), n, why);
-		kfree_skb_reason(skb, SKB_CONSUMED);
+		consume_skb(skb);
 	}
 }
 
@@ -78,6 +78,6 @@ void rxrpc_purge_queue(struct sk_buff_head *list)
 		int n = atomic_dec_return(select_skb_count(skb));
 		trace_rxrpc_skb(skb, refcount_read(&skb->users), n,
 				rxrpc_skb_put_purge);
-		kfree_skb_reason(skb, SKB_CONSUMED);
+		consume_skb(skb);
 	}
 }