Merge branch 'net-tls-add-ctrl-path-tracing-and-statistics'

Jakub Kicinski says:

====================
net/tls: add ctrl path tracing and statistics

This set adds trace events related to TLS offload and basic MIB stats
for TLS.

First patch contains the TLS offload related trace points. Those are
helpful in troubleshooting offload issues, especially around the
resync paths.

Second patch adds a tracepoint to the fastpath of device offload,
it's separated out in case there will be objections to adding
fast path tracepoints. Again, it's quite useful for debugging
offload issues.

Next four patches add MIB statistics. The statistics are implemented
as per-cpu per-netns counters. Since there are currently no fast path
statistics we could move to atomic variables. Per-CPU seem more common.

Most basic statistics are number of created and live sessions, broken
out to offloaded and non-offloaded. Users seem to like those a lot.

Next there is a statistic for decryption errors. These are primarily
useful for device offload debug, in normal deployments decryption
errors should not be common.

Last but not least a counter for device RX resync.
====================

Reviewed-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 56 insertions, 4 deletions

diff --git a/net/tls/tls_main.c b/net/tls/tls_main.c
index 237e58e4928a..f144b965704e 100644
--- a/net/tls/tls_main.c
+++ b/net/tls/tls_main.c
@@ -41,6 +41,7 @@
 #include <linux/inetdevice.h>
 #include <linux/inet_diag.h>
 
+#include <net/snmp.h>
 #include <net/tls.h>
 #include <net/tls_toe.h>
 
@@ -285,14 +286,19 @@ static void tls_sk_proto_cleanup(struct sock *sk,
 		kfree(ctx->tx.rec_seq);
 		kfree(ctx->tx.iv);
 		tls_sw_release_resources_tx(sk);
+		TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXSW);
 	} else if (ctx->tx_conf == TLS_HW) {
 		tls_device_free_resources_tx(sk);
+		TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXDEVICE);
 	}
 
-	if (ctx->rx_conf == TLS_SW)
+	if (ctx->rx_conf == TLS_SW) {
 		tls_sw_release_resources_rx(sk);
-	else if (ctx->rx_conf == TLS_HW)
+		TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXSW);
+	} else if (ctx->rx_conf == TLS_HW) {
 		tls_device_offload_cleanup_rx(sk);
+		TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXDEVICE);
+	}
 }
 
 static void tls_sk_proto_close(struct sock *sk, long timeout)
@@ -533,19 +539,29 @@ static int do_tls_setsockopt_conf(struct sock *sk, char __user *optval,
 	if (tx) {
 		rc = tls_set_device_offload(sk, ctx);
 		conf = TLS_HW;
-		if (rc) {
+		if (!rc) {
+			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSTXDEVICE);
+			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXDEVICE);
+		} else {
 			rc = tls_set_sw_offload(sk, ctx, 1);
 			if (rc)
 				goto err_crypto_info;
+			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSTXSW);
+			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXSW);
 			conf = TLS_SW;
 		}
 	} else {
 		rc = tls_set_device_offload_rx(sk, ctx);
 		conf = TLS_HW;
-		if (rc) {
+		if (!rc) {
+			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXDEVICE);
+			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXDEVICE);
+		} else {
 			rc = tls_set_sw_offload(sk, ctx, 0);
 			if (rc)
 				goto err_crypto_info;
+			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXSW);
+			TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXSW);
 			conf = TLS_SW;
 		}
 		tls_sw_strparser_arm(sk, ctx);
@@ -795,6 +811,35 @@ static size_t tls_get_info_size(const struct sock *sk)
 	return size;
 }
 
+static int __net_init tls_init_net(struct net *net)
+{
+	int err;
+
+	net->mib.tls_statistics = alloc_percpu(struct linux_tls_mib);
+	if (!net->mib.tls_statistics)
+		return -ENOMEM;
+
+	err = tls_proc_init(net);
+	if (err)
+		goto err_free_stats;
+
+	return 0;
+err_free_stats:
+	free_percpu(net->mib.tls_statistics);
+	return err;
+}
+
+static void __net_exit tls_exit_net(struct net *net)
+{
+	tls_proc_fini(net);
+	free_percpu(net->mib.tls_statistics);
+}
+
+static struct pernet_operations tls_proc_ops = {
+	.init = tls_init_net,
+	.exit = tls_exit_net,
+};
+
 static struct tcp_ulp_ops tcp_tls_ulp_ops __read_mostly = {
 	.name			= "tls",
 	.owner			= THIS_MODULE,
@@ -806,6 +851,12 @@ static struct tcp_ulp_ops tcp_tls_ulp_ops __read_mostly = {
 
 static int __init tls_register(void)
 {
+	int err;
+
+	err = register_pernet_subsys(&tls_proc_ops);
+	if (err)
+		return err;
+
 	tls_sw_proto_ops = inet_stream_ops;
 	tls_sw_proto_ops.splice_read = tls_sw_splice_read;
 
@@ -819,6 +870,7 @@ static void __exit tls_unregister(void)
 {
 	tcp_unregister_ulp(&tcp_tls_ulp_ops);
 	tls_device_cleanup();
+	unregister_pernet_subsys(&tls_proc_ops);
 }
 
 module_init(tls_register);