From: Geneviève Bastien <gbastien@versatic.net>
Date: Wed, 19 Jun 2019 19:03:49 +0000 (-0400)
Subject: net: Add entry/exit tracepoints for all receive paths
X-Git-Tag: v2.12.0-pre~18
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=e9d818b9d564b1ca885fc0b8a6d08b0d205c606f;p=lttng-modules.git

net: Add entry/exit tracepoints for all receive paths

In the linux kernel, there are entry and exit tracepoints on
the various paths of network reception.

Those tracepoints are useful to bound the network reception such that
all events happening between the entry and exit can be linked to this
network reception (for example, wakeups). They can also be used to
perform network stack latency analysis.

Acked-by: Julien Desfossez <jdesfossez@digitalocean.com>
Signed-off-by: Geneviève Bastien <gbastien@versatic.net>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
---

diff --git a/instrumentation/events/lttng-module/net.h b/instrumentation/events/lttng-module/net.h
index bfa14fc6..7dd68957 100644
--- a/instrumentation/events/lttng-module/net.h
+++ b/instrumentation/events/lttng-module/net.h
@@ -553,6 +553,175 @@ LTTNG_TRACEPOINT_EVENT_INSTANCE_MAP(net_dev_template,
 
 	TP_ARGS(skb)
 )
+
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,14,0))
+
+/* Trace events for the receive entry points */
+LTTNG_TRACEPOINT_EVENT_CLASS(net_dev_receive_entry_template,
+
+	TP_PROTO(const struct sk_buff *skb),
+
+	TP_ARGS(skb),
+
+	TP_FIELDS(
+		ctf_integer_hex(const void *, skbaddr, skb)
+	)
+)
+
+LTTNG_TRACEPOINT_EVENT_INSTANCE_MAP(net_dev_receive_entry_template,
+
+	napi_gro_frags_entry,
+
+	net_napi_gro_frags_entry,
+
+	TP_PROTO(const struct sk_buff *skb),
+
+	TP_ARGS(skb)
+)
+
+LTTNG_TRACEPOINT_EVENT_INSTANCE_MAP(net_dev_receive_entry_template,
+
+	napi_gro_receive_entry,
+
+	net_napi_gro_receive_entry,
+
+	TP_PROTO(const struct sk_buff *skb),
+
+	TP_ARGS(skb)
+)
+
+LTTNG_TRACEPOINT_EVENT_INSTANCE_MAP(net_dev_receive_entry_template,
+
+	netif_receive_skb_entry,
+
+	net_if_receive_skb_entry,
+
+	TP_PROTO(const struct sk_buff *skb),
+
+	TP_ARGS(skb)
+)
+
+LTTNG_TRACEPOINT_EVENT_INSTANCE_MAP(net_dev_receive_entry_template,
+
+	netif_rx_entry,
+
+	net_if_rx_entry,
+
+	TP_PROTO(const struct sk_buff *skb),
+
+	TP_ARGS(skb)
+)
+
+LTTNG_TRACEPOINT_EVENT_INSTANCE_MAP(net_dev_receive_entry_template,
+
+	netif_rx_ni_entry,
+
+	net_if_rx_ni_entry,
+
+	TP_PROTO(const struct sk_buff *skb),
+
+	TP_ARGS(skb)
+)
+
+#endif /* kernel > 3.14 */
+
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,19,0))
+
+LTTNG_TRACEPOINT_EVENT_INSTANCE_MAP(net_dev_receive_entry_template,
+
+	netif_receive_skb_list_entry,
+
+	net_if_receive_skb_list_entry,
+
+	TP_PROTO(const struct sk_buff *skb),
+
+	TP_ARGS(skb)
+)
+
+#endif /* kernel > 4.19 */
+
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,0,0))
+
+/* Trace events for the receive exit points */
+LTTNG_TRACEPOINT_EVENT_CLASS(net_dev_receive_exit_template,
+
+	TP_PROTO(int ret),
+
+	TP_ARGS(ret),
+
+	TP_FIELDS(
+		ctf_integer(int, ret, ret)
+	)
+)
+
+LTTNG_TRACEPOINT_EVENT_INSTANCE_MAP(net_dev_receive_exit_template,
+
+	napi_gro_frags_exit,
+
+	net_napi_gro_frags_exit,
+
+	TP_PROTO(int ret),
+
+	TP_ARGS(ret)
+)
+
+LTTNG_TRACEPOINT_EVENT_INSTANCE_MAP(net_dev_receive_exit_template,
+
+	napi_gro_receive_exit,
+
+	net_napi_gro_receive_exit,
+
+	TP_PROTO(int ret),
+
+	TP_ARGS(ret)
+)
+
+LTTNG_TRACEPOINT_EVENT_INSTANCE_MAP(net_dev_receive_exit_template,
+
+	netif_receive_skb_exit,
+
+	net_if_receive_skb_exit,
+
+	TP_PROTO(int ret),
+
+	TP_ARGS(ret)
+)
+
+LTTNG_TRACEPOINT_EVENT_INSTANCE_MAP(net_dev_receive_exit_template,
+
+	netif_rx_exit,
+
+	net_if_rx_exit,
+
+	TP_PROTO(int ret),
+
+	TP_ARGS(ret)
+)
+
+LTTNG_TRACEPOINT_EVENT_INSTANCE_MAP(net_dev_receive_exit_template,
+
+	netif_rx_ni_exit,
+
+	net_if_rx_ni_exit,
+
+	TP_PROTO(int ret),
+
+	TP_ARGS(ret)
+)
+
+LTTNG_TRACEPOINT_EVENT_INSTANCE_MAP(net_dev_receive_exit_template,
+
+	netif_receive_skb_list_exit,
+
+	net_if_receive_skb_list_exit,
+
+	TP_PROTO(int ret),
+
+	TP_ARGS(ret)
+)
+
+#endif /* kernel > 5.0.0 */
+
 #endif /* LTTNG_TRACE_NET_H */
 
 /* This part must be outside protection */