[PATCH net-next v6 5/6] net: dccp: Add DCCP sendmsg trace event

From: Masami Hiramatsu
Date: Thu Dec 28 2017 - 01:13:01 EST


Add DCCP sendmsg trace event (dccp/dccp_probe) for
replacing dccpprobe. User can trace this event via
ftrace or perftools.

Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
---
Changes in v5
- Fix to add local directory to include for trace.h.
Thanks Steven!
---
net/dccp/Makefile | 3 ++
net/dccp/proto.c | 5 +++
net/dccp/trace.h | 105 +++++++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 113 insertions(+)
create mode 100644 net/dccp/trace.h

diff --git a/net/dccp/Makefile b/net/dccp/Makefile
index 2e7b56097bc4..4215f13a63af 100644
--- a/net/dccp/Makefile
+++ b/net/dccp/Makefile
@@ -27,3 +27,6 @@ dccp-$(CONFIG_SYSCTL) += sysctl.o

dccp_diag-y := diag.o
dccp_probe-y := probe.o
+
+# build with local directory for trace.h
+CFLAGS_proto.o := -I$(src)
diff --git a/net/dccp/proto.c b/net/dccp/proto.c
index 7a75a1d3568b..fa7e92e08920 100644
--- a/net/dccp/proto.c
+++ b/net/dccp/proto.c
@@ -38,6 +38,9 @@
#include "dccp.h"
#include "feat.h"

+#define CREATE_TRACE_POINTS
+#include "trace.h"
+
DEFINE_SNMP_STAT(struct dccp_mib, dccp_statistics) __read_mostly;

EXPORT_SYMBOL_GPL(dccp_statistics);
@@ -761,6 +764,8 @@ int dccp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
int rc, size;
long timeo;

+ trace_dccp_probe(sk, len);
+
if (len > dp->dccps_mss_cache)
return -EMSGSIZE;

diff --git a/net/dccp/trace.h b/net/dccp/trace.h
new file mode 100644
index 000000000000..aa01321a6c37
--- /dev/null
+++ b/net/dccp/trace.h
@@ -0,0 +1,105 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM dccp
+
+#if !defined(_TRACE_DCCP_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_DCCP_H
+
+#include <net/sock.h>
+#include "dccp.h"
+#include "ccids/ccid3.h"
+#include <linux/tracepoint.h>
+
+TRACE_EVENT(dccp_probe,
+
+ TP_PROTO(struct sock *sk, size_t size),
+
+ TP_ARGS(sk, size),
+
+ TP_STRUCT__entry(
+ /* sockaddr_in6 is always bigger than sockaddr_in */
+ __array(__u8, saddr, sizeof(struct sockaddr_in6))
+ __array(__u8, daddr, sizeof(struct sockaddr_in6))
+ __field(__u16, sport)
+ __field(__u16, dport)
+ __field(__u16, size)
+ __field(__u16, tx_s)
+ __field(__u32, tx_rtt)
+ __field(__u32, tx_p)
+ __field(__u32, tx_x_calc)
+ __field(__u64, tx_x_recv)
+ __field(__u64, tx_x)
+ __field(__u32, tx_t_ipi)
+ ),
+
+ TP_fast_assign(
+ const struct inet_sock *inet = inet_sk(sk);
+ struct ccid3_hc_tx_sock *hc = NULL;
+
+ if (ccid_get_current_tx_ccid(dccp_sk(sk)) == DCCPC_CCID3)
+ hc = ccid3_hc_tx_sk(sk);
+
+ memset(__entry->saddr, 0, sizeof(struct sockaddr_in6));
+ memset(__entry->daddr, 0, sizeof(struct sockaddr_in6));
+
+ if (sk->sk_family == AF_INET) {
+ struct sockaddr_in *v4 = (void *)__entry->saddr;
+
+ v4->sin_family = AF_INET;
+ v4->sin_port = inet->inet_sport;
+ v4->sin_addr.s_addr = inet->inet_saddr;
+ v4 = (void *)__entry->daddr;
+ v4->sin_family = AF_INET;
+ v4->sin_port = inet->inet_dport;
+ v4->sin_addr.s_addr = inet->inet_daddr;
+#if IS_ENABLED(CONFIG_IPV6)
+ } else if (sk->sk_family == AF_INET6) {
+ struct sockaddr_in6 *v6 = (void *)__entry->saddr;
+
+ v6->sin6_family = AF_INET6;
+ v6->sin6_port = inet->inet_sport;
+ v6->sin6_addr = inet6_sk(sk)->saddr;
+ v6 = (void *)__entry->daddr;
+ v6->sin6_family = AF_INET6;
+ v6->sin6_port = inet->inet_dport;
+ v6->sin6_addr = sk->sk_v6_daddr;
+#endif
+ }
+
+ /* For filtering use */
+ __entry->sport = ntohs(inet->inet_sport);
+ __entry->dport = ntohs(inet->inet_dport);
+
+ __entry->size = size;
+ if (hc) {
+ __entry->tx_s = hc->tx_s;
+ __entry->tx_rtt = hc->tx_rtt;
+ __entry->tx_p = hc->tx_p;
+ __entry->tx_x_calc = hc->tx_x_calc;
+ __entry->tx_x_recv = hc->tx_x_recv >> 6;
+ __entry->tx_x = hc->tx_x >> 6;
+ __entry->tx_t_ipi = hc->tx_t_ipi;
+ } else {
+ __entry->tx_s = 0;
+ memset(&__entry->tx_rtt, 0, (void *)&__entry->tx_t_ipi -
+ (void *)&__entry->tx_rtt +
+ sizeof(__entry->tx_t_ipi));
+ }
+ ),
+
+ TP_printk("src=%pISpc dest=%pISpc size=%d tx_s=%d tx_rtt=%d "
+ "tx_p=%d tx_x_calc=%u tx_x_recv=%llu tx_x=%llu tx_t_ipi=%d",
+ __entry->saddr, __entry->daddr, __entry->size,
+ __entry->tx_s, __entry->tx_rtt, __entry->tx_p,
+ __entry->tx_x_calc, __entry->tx_x_recv, __entry->tx_x,
+ __entry->tx_t_ipi)
+);
+
+#endif /* _TRACE_TCP_H */
+
+/* This part must be outside protection */
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH .
+#undef TRACE_INCLUDE_FILE
+#define TRACE_INCLUDE_FILE trace
+#include <trace/define_trace.h>