rxrpc: Display stats about jumbo packets transmitted and received

In /proc/net/rxrpc/stats, display statistics about the numbers of different
sizes of jumbo packets transmitted and received, showing counts for 1
subpacket (ie. a non-jumbo packet), 2 subpackets, 3, ... to 8 and then 9+.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
Link: https://patch.msgid.link/20241204074710.990092-22-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

4 files changed, 37 insertions, 2 deletions

diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index 3e57cef7385f..840293f913a3 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -111,6 +111,8 @@ struct rxrpc_net {
 	atomic_t		stat_tx_ack_skip;
 	atomic_t		stat_tx_acks[256];
 	atomic_t		stat_rx_acks[256];
+	atomic_t		stat_tx_jumbo[10];
+	atomic_t		stat_rx_jumbo[10];
 
 	atomic_t		stat_why_req_ack[8];
 
diff --git a/net/rxrpc/input.c b/net/rxrpc/input.c
index b89fd0dee324..8d7ab4b9d7d0 100644
--- a/net/rxrpc/input.c
+++ b/net/rxrpc/input.c
@@ -568,7 +568,7 @@ static bool rxrpc_input_split_jumbo(struct rxrpc_call *call, struct sk_buff *skb
 	unsigned int offset = sizeof(struct rxrpc_wire_header);
 	unsigned int len = skb->len - offset;
 	bool notify = false;
-	int ack_reason = 0;
+	int ack_reason = 0, count = 1, stat_ix;
 
 	while (sp->hdr.flags & RXRPC_JUMBO_PACKET) {
 		if (len < RXRPC_JUMBO_SUBPKTLEN)
@@ -597,12 +597,16 @@ static bool rxrpc_input_split_jumbo(struct rxrpc_call *call, struct sk_buff *skb
 		sp->hdr.serial++;
 		offset += RXRPC_JUMBO_SUBPKTLEN;
 		len -= RXRPC_JUMBO_SUBPKTLEN;
+		count++;
 	}
 
 	sp->offset = offset;
 	sp->len    = len;
 	rxrpc_input_data_one(call, skb, &notify, &ack_serial, &ack_reason);
 
+	stat_ix = umin(count, ARRAY_SIZE(call->rxnet->stat_rx_jumbo)) - 1;
+	atomic_inc(&call->rxnet->stat_rx_jumbo[stat_ix]);
+
 	if (ack_reason > 0) {
 		rxrpc_send_ACK(call, ack_reason, ack_serial,
 			       rxrpc_propose_ack_input_data);
diff --git a/net/rxrpc/output.c b/net/rxrpc/output.c
index c2044d593237..3886777d1bb6 100644
--- a/net/rxrpc/output.c
+++ b/net/rxrpc/output.c
@@ -552,10 +552,13 @@ void rxrpc_send_data_packet(struct rxrpc_call *call, struct rxrpc_send_data_req
 	rxrpc_seq_t seq = req->seq;
 	size_t len;
 	bool new_call = test_bit(RXRPC_CALL_BEGAN_RX_TIMER, &call->flags);
-	int ret;
+	int ret, stat_ix;
 
 	_enter("%x,%x-%x", tq->qbase, seq, seq + req->n - 1);
 
+	stat_ix = umin(req->n, ARRAY_SIZE(call->rxnet->stat_tx_jumbo)) - 1;
+	atomic_inc(&call->rxnet->stat_tx_jumbo[stat_ix]);
+
 	len = rxrpc_prepare_data_packet(call, req);
 	txb = tq->bufs[seq & RXRPC_TXQ_MASK];
 
diff --git a/net/rxrpc/proc.c b/net/rxrpc/proc.c
index a8325b8e33c2..5f974ec13d69 100644
--- a/net/rxrpc/proc.c
+++ b/net/rxrpc/proc.c
@@ -530,6 +530,30 @@ int rxrpc_stats_show(struct seq_file *seq, void *v)
 		   atomic_read(&rxnet->stat_why_req_ack[rxrpc_reqack_slow_start]),
 		   atomic_read(&rxnet->stat_why_req_ack[rxrpc_reqack_small_txwin]));
 	seq_printf(seq,
+		   "Jumbo-Tx : %u,%u,%u,%u,%u,%u,%u,%u,%u,%u\n",
+		   atomic_read(&rxnet->stat_tx_jumbo[0]),
+		   atomic_read(&rxnet->stat_tx_jumbo[1]),
+		   atomic_read(&rxnet->stat_tx_jumbo[2]),
+		   atomic_read(&rxnet->stat_tx_jumbo[3]),
+		   atomic_read(&rxnet->stat_tx_jumbo[4]),
+		   atomic_read(&rxnet->stat_tx_jumbo[5]),
+		   atomic_read(&rxnet->stat_tx_jumbo[6]),
+		   atomic_read(&rxnet->stat_tx_jumbo[7]),
+		   atomic_read(&rxnet->stat_tx_jumbo[8]),
+		   atomic_read(&rxnet->stat_tx_jumbo[9]));
+	seq_printf(seq,
+		   "Jumbo-Rx : %u,%u,%u,%u,%u,%u,%u,%u,%u,%u\n",
+		   atomic_read(&rxnet->stat_rx_jumbo[0]),
+		   atomic_read(&rxnet->stat_rx_jumbo[1]),
+		   atomic_read(&rxnet->stat_rx_jumbo[2]),
+		   atomic_read(&rxnet->stat_rx_jumbo[3]),
+		   atomic_read(&rxnet->stat_rx_jumbo[4]),
+		   atomic_read(&rxnet->stat_rx_jumbo[5]),
+		   atomic_read(&rxnet->stat_rx_jumbo[6]),
+		   atomic_read(&rxnet->stat_rx_jumbo[7]),
+		   atomic_read(&rxnet->stat_rx_jumbo[8]),
+		   atomic_read(&rxnet->stat_rx_jumbo[9]));
+	seq_printf(seq,
 		   "Buffers  : txb=%u rxb=%u\n",
 		   atomic_read(&rxrpc_nr_txbuf),
 		   atomic_read(&rxrpc_n_rx_skbs));
@@ -566,6 +590,8 @@ int rxrpc_stats_clear(struct file *file, char *buf, size_t size)
 	atomic_set(&rxnet->stat_tx_ack_skip, 0);
 	memset(&rxnet->stat_tx_acks, 0, sizeof(rxnet->stat_tx_acks));
 	memset(&rxnet->stat_rx_acks, 0, sizeof(rxnet->stat_rx_acks));
+	memset(&rxnet->stat_tx_jumbo, 0, sizeof(rxnet->stat_tx_jumbo));
+	memset(&rxnet->stat_rx_jumbo, 0, sizeof(rxnet->stat_rx_jumbo));
 
 	memset(&rxnet->stat_why_req_ack, 0, sizeof(rxnet->stat_why_req_ack));