SUNRPC: add a handful of per-xprt counters

Monitor generic transport events.  Add a transport switch callout to
format transport counters for export to user-land.

Test plan:
Compile kernel with CONFIG_NFS enabled.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 48 insertions, 0 deletions

diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
index c458f8d..6766b7f 100644
--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -1114,6 +1114,8 @@ static void xs_tcp_connect_worker(void *args)
 	}
 
 	/* Tell the socket layer to start connecting... */
+	xprt->stat.connect_count++;
+	xprt->stat.connect_start = jiffies;
 	status = sock->ops->connect(sock, (struct sockaddr *) &xprt->addr,
 			sizeof(xprt->addr), O_NONBLOCK);
 	dprintk("RPC: %p  connect status %d connected %d sock state %d\n",
@@ -1177,6 +1179,50 @@ static void xs_connect(struct rpc_task *task)
 	}
 }
 
+/**
+ * xs_udp_print_stats - display UDP socket-specifc stats
+ * @xprt: rpc_xprt struct containing statistics
+ * @seq: output file
+ *
+ */
+static void xs_udp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
+{
+	seq_printf(seq, "\txprt:\tudp %u %lu %lu %lu %lu %Lu %Lu\n",
+			xprt->port,
+			xprt->stat.bind_count,
+			xprt->stat.sends,
+			xprt->stat.recvs,
+			xprt->stat.bad_xids,
+			xprt->stat.req_u,
+			xprt->stat.bklog_u);
+}
+
+/**
+ * xs_tcp_print_stats - display TCP socket-specifc stats
+ * @xprt: rpc_xprt struct containing statistics
+ * @seq: output file
+ *
+ */
+static void xs_tcp_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
+{
+	long idle_time = 0;
+
+	if (xprt_connected(xprt))
+		idle_time = (long)(jiffies - xprt->last_used) / HZ;
+
+	seq_printf(seq, "\txprt:\ttcp %u %lu %lu %lu %ld %lu %lu %lu %Lu %Lu\n",
+			xprt->port,
+			xprt->stat.bind_count,
+			xprt->stat.connect_count,
+			xprt->stat.connect_time,
+			idle_time,
+			xprt->stat.sends,
+			xprt->stat.recvs,
+			xprt->stat.bad_xids,
+			xprt->stat.req_u,
+			xprt->stat.bklog_u);
+}
+
 static struct rpc_xprt_ops xs_udp_ops = {
 	.set_buffer_size	= xs_udp_set_buffer_size,
 	.reserve_xprt		= xprt_reserve_xprt_cong,
@@ -1191,6 +1237,7 @@ static struct rpc_xprt_ops xs_udp_ops = {
 	.release_request	= xprt_release_rqst_cong,
 	.close			= xs_close,
 	.destroy		= xs_destroy,
+	.print_stats		= xs_udp_print_stats,
 };
 
 static struct rpc_xprt_ops xs_tcp_ops = {
@@ -1204,6 +1251,7 @@ static struct rpc_xprt_ops xs_tcp_ops = {
 	.set_retrans_timeout	= xprt_set_retrans_timeout_def,
 	.close			= xs_close,
 	.destroy		= xs_destroy,
+	.print_stats		= xs_tcp_print_stats,
 };
 
 /**