[PATCH net-next 1/3] net:tracepoint: replace tcp_set_state tracepoint with sock_set_state tracepoint

From: Yafang Shao
Date: Sun Dec 10 2017 - 10:32:19 EST


As sk_state is a common field for struct sock, so the state
transition should not be a TCP specific feature.
So I rename tcp_set_state tracepoint to sock_set_state tracepoint with
some minor changes and move it into file trace/events/sock.h.

The minor changes against on the original tcp_set_state tracepoint:
- Protocol name is printed to distinguish which protocol it is belonging
to
- The macros defined in the file are undefed at the end of this file as
they are only used in this file

Two helpers are introduced to trace sk_state transition
- void sk_state_store(struct sock *sk, int state);
- void sk_set_state(struct sock *sk, int state);

As trace header should not be included in other header files,
so they are defined in sock.c.

The protocol such as SCTP maybe compiled as a ko, hence export
sk_set_state().

Signed-off-by: Yafang Shao <laoar.shao@xxxxxxxxx>
---
include/net/sock.h | 15 ++-----
include/trace/events/sock.h | 95 +++++++++++++++++++++++++++++++++++++++++
include/trace/events/tcp.h | 76 ---------------------------------
net/core/sock.c | 13 ++++++
net/ipv4/inet_connection_sock.c | 4 +-
net/ipv4/inet_hashtables.c | 2 +-
net/ipv4/tcp.c | 4 --
7 files changed, 114 insertions(+), 95 deletions(-)

diff --git a/include/net/sock.h b/include/net/sock.h
index 79e1a2c..b307b60 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -2348,18 +2348,9 @@ static inline int sk_state_load(const struct sock *sk)
return smp_load_acquire(&sk->sk_state);
}

-/**
- * sk_state_store - update sk->sk_state
- * @sk: socket pointer
- * @newstate: new state
- *
- * Paired with sk_state_load(). Should be used in contexts where
- * state change might impact lockless readers.
- */
-static inline void sk_state_store(struct sock *sk, int newstate)
-{
- smp_store_release(&sk->sk_state, newstate);
-}
+/* For sock_set_state tracepoint */
+void sk_state_store(struct sock *sk, int newstate);
+void sk_set_state(struct sock *sk, int state);

void sock_enable_timestamp(struct sock *sk, int flag);
int sock_get_timestamp(struct sock *, struct timeval __user *);
diff --git a/include/trace/events/sock.h b/include/trace/events/sock.h
index ec4dade..2728892 100644
--- a/include/trace/events/sock.h
+++ b/include/trace/events/sock.h
@@ -6,7 +6,33 @@
#define _TRACE_SOCK_H

#include <net/sock.h>
+#include <net/ipv6.h>
#include <linux/tracepoint.h>
+#include <linux/ipv6.h>
+#include <linux/tcp.h>
+
+#define inet_protocol_name(protocol) {IPPROTO_##protocol, #protocol}
+#define show_inet_protocol_name(val) \
+ __print_symbolic(val, \
+ inet_protocol_name(TCP), \
+ inet_protocol_name(DCCP), \
+ inet_protocol_name(SCTP))
+
+#define tcp_state_name(state) { state, #state }
+#define show_tcp_state_name(val) \
+ __print_symbolic(val, \
+ tcp_state_name(TCP_ESTABLISHED), \
+ tcp_state_name(TCP_SYN_SENT), \
+ tcp_state_name(TCP_SYN_RECV), \
+ tcp_state_name(TCP_FIN_WAIT1), \
+ tcp_state_name(TCP_FIN_WAIT2), \
+ tcp_state_name(TCP_TIME_WAIT), \
+ tcp_state_name(TCP_CLOSE), \
+ tcp_state_name(TCP_CLOSE_WAIT), \
+ tcp_state_name(TCP_LAST_ACK), \
+ tcp_state_name(TCP_LISTEN), \
+ tcp_state_name(TCP_CLOSING), \
+ tcp_state_name(TCP_NEW_SYN_RECV))

TRACE_EVENT(sock_rcvqueue_full,

@@ -63,6 +89,75 @@
__entry->rmem_alloc)
);

+TRACE_EVENT(sock_set_state,
+
+ TP_PROTO(const struct sock *sk, const int oldstate, const int newstate),
+
+ TP_ARGS(sk, oldstate, newstate),
+
+ TP_STRUCT__entry(
+ __field(const void *, skaddr)
+ __field(int, oldstate)
+ __field(int, newstate)
+ __field(__u16, sport)
+ __field(__u16, dport)
+ __field(__u8, protocol);
+ __array(__u8, saddr, 4)
+ __array(__u8, daddr, 4)
+ __array(__u8, saddr_v6, 16)
+ __array(__u8, daddr_v6, 16)
+ ),
+
+ TP_fast_assign(
+ struct inet_sock *inet = inet_sk(sk);
+ struct in6_addr *pin6;
+ __be32 *p32;
+
+ __entry->skaddr = sk;
+ __entry->oldstate = oldstate;
+ __entry->newstate = newstate;
+
+ __entry->protocol = sk->sk_protocol;
+ __entry->sport = ntohs(inet->inet_sport);
+ __entry->dport = ntohs(inet->inet_dport);
+
+ p32 = (__be32 *) __entry->saddr;
+ *p32 = inet->inet_saddr;
+
+ p32 = (__be32 *) __entry->daddr;
+ *p32 = inet->inet_daddr;
+
+#if IS_ENABLED(CONFIG_IPV6)
+ if (sk->sk_family == AF_INET6) {
+ pin6 = (struct in6_addr *)__entry->saddr_v6;
+ *pin6 = sk->sk_v6_rcv_saddr;
+ pin6 = (struct in6_addr *)__entry->daddr_v6;
+ *pin6 = sk->sk_v6_daddr;
+ } else
+#endif
+ {
+ pin6 = (struct in6_addr *)__entry->saddr_v6;
+ ipv6_addr_set_v4mapped(inet->inet_saddr, pin6);
+ pin6 = (struct in6_addr *)__entry->daddr_v6;
+ ipv6_addr_set_v4mapped(inet->inet_daddr, pin6);
+ }
+ ),
+
+ TP_printk("protocol=%s sport=%hu dport=%hu saddr=%pI4 daddr=%pI4"
+ "saddrv6=%pI6c daddrv6=%pI6c oldstate=%s newstate=%s",
+ show_inet_protocol_name(__entry->protocol),
+ __entry->sport, __entry->dport,
+ __entry->saddr, __entry->daddr,
+ __entry->saddr_v6, __entry->daddr_v6,
+ show_tcp_state_name(__entry->oldstate),
+ show_tcp_state_name(__entry->newstate))
+);
+
+#undef show_tcp_state_name
+#undef tcp_state_name
+#undef show_inet_protocol_name
+#undef inet_protocol_name
+
#endif /* _TRACE_SOCK_H */

/* This part must be outside protection */
diff --git a/include/trace/events/tcp.h b/include/trace/events/tcp.h
index 07cccca..7399399 100644
--- a/include/trace/events/tcp.h
+++ b/include/trace/events/tcp.h
@@ -9,22 +9,6 @@
#include <linux/tracepoint.h>
#include <net/ipv6.h>

-#define tcp_state_name(state) { state, #state }
-#define show_tcp_state_name(val) \
- __print_symbolic(val, \
- tcp_state_name(TCP_ESTABLISHED), \
- tcp_state_name(TCP_SYN_SENT), \
- tcp_state_name(TCP_SYN_RECV), \
- tcp_state_name(TCP_FIN_WAIT1), \
- tcp_state_name(TCP_FIN_WAIT2), \
- tcp_state_name(TCP_TIME_WAIT), \
- tcp_state_name(TCP_CLOSE), \
- tcp_state_name(TCP_CLOSE_WAIT), \
- tcp_state_name(TCP_LAST_ACK), \
- tcp_state_name(TCP_LISTEN), \
- tcp_state_name(TCP_CLOSING), \
- tcp_state_name(TCP_NEW_SYN_RECV))
-
/*
* tcp event with arguments sk and skb
*
@@ -177,66 +161,6 @@
TP_ARGS(sk)
);

-TRACE_EVENT(tcp_set_state,
-
- TP_PROTO(const struct sock *sk, const int oldstate, const int newstate),
-
- TP_ARGS(sk, oldstate, newstate),
-
- TP_STRUCT__entry(
- __field(const void *, skaddr)
- __field(int, oldstate)
- __field(int, newstate)
- __field(__u16, sport)
- __field(__u16, dport)
- __array(__u8, saddr, 4)
- __array(__u8, daddr, 4)
- __array(__u8, saddr_v6, 16)
- __array(__u8, daddr_v6, 16)
- ),
-
- TP_fast_assign(
- struct inet_sock *inet = inet_sk(sk);
- struct in6_addr *pin6;
- __be32 *p32;
-
- __entry->skaddr = sk;
- __entry->oldstate = oldstate;
- __entry->newstate = newstate;
-
- __entry->sport = ntohs(inet->inet_sport);
- __entry->dport = ntohs(inet->inet_dport);
-
- p32 = (__be32 *) __entry->saddr;
- *p32 = inet->inet_saddr;
-
- p32 = (__be32 *) __entry->daddr;
- *p32 = inet->inet_daddr;
-
-#if IS_ENABLED(CONFIG_IPV6)
- if (sk->sk_family == AF_INET6) {
- pin6 = (struct in6_addr *)__entry->saddr_v6;
- *pin6 = sk->sk_v6_rcv_saddr;
- pin6 = (struct in6_addr *)__entry->daddr_v6;
- *pin6 = sk->sk_v6_daddr;
- } else
-#endif
- {
- pin6 = (struct in6_addr *)__entry->saddr_v6;
- ipv6_addr_set_v4mapped(inet->inet_saddr, pin6);
- pin6 = (struct in6_addr *)__entry->daddr_v6;
- ipv6_addr_set_v4mapped(inet->inet_daddr, pin6);
- }
- ),
-
- TP_printk("sport=%hu dport=%hu saddr=%pI4 daddr=%pI4 saddrv6=%pI6c daddrv6=%pI6c oldstate=%s newstate=%s",
- __entry->sport, __entry->dport,
- __entry->saddr, __entry->daddr,
- __entry->saddr_v6, __entry->daddr_v6,
- show_tcp_state_name(__entry->oldstate),
- show_tcp_state_name(__entry->newstate))
-);
-
TRACE_EVENT(tcp_retransmit_synack,

TP_PROTO(const struct sock *sk, const struct request_sock *req),
diff --git a/net/core/sock.c b/net/core/sock.c
index c0b5b2f..ee0c1bc 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -2859,6 +2859,19 @@ int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
}
EXPORT_SYMBOL(sock_get_timestampns);

+void sk_state_store(struct sock *sk, int state)
+{
+ trace_sock_set_state(sk, sk->sk_state, state);
+ smp_store_release(&sk->sk_state, state);
+}
+
+void sk_set_state(struct sock *sk, int state)
+{
+ trace_sock_set_state(sk, sk->sk_state, state);
+ sk->sk_state = state;
+}
+EXPORT_SYMBOL(sk_set_state);
+
void sock_enable_timestamp(struct sock *sk, int flag)
{
if (!sock_flag(sk, flag)) {
diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c
index 4ca46dc..001f7b0 100644
--- a/net/ipv4/inet_connection_sock.c
+++ b/net/ipv4/inet_connection_sock.c
@@ -783,7 +783,7 @@ struct sock *inet_csk_clone_lock(const struct sock *sk,
if (newsk) {
struct inet_connection_sock *newicsk = inet_csk(newsk);

- newsk->sk_state = TCP_SYN_RECV;
+ sk_set_state(newsk, TCP_SYN_RECV);
newicsk->icsk_bind_hash = NULL;

inet_sk(newsk)->inet_dport = inet_rsk(req)->ir_rmt_port;
@@ -888,7 +888,7 @@ int inet_csk_listen_start(struct sock *sk, int backlog)
return 0;
}

- sk->sk_state = TCP_CLOSE;
+ sk_set_state(sk, TCP_CLOSE);
return err;
}
EXPORT_SYMBOL_GPL(inet_csk_listen_start);
diff --git a/net/ipv4/inet_hashtables.c b/net/ipv4/inet_hashtables.c
index f6f5810..5973693 100644
--- a/net/ipv4/inet_hashtables.c
+++ b/net/ipv4/inet_hashtables.c
@@ -544,7 +544,7 @@ bool inet_ehash_nolisten(struct sock *sk, struct sock *osk)
sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
} else {
percpu_counter_inc(sk->sk_prot->orphan_count);
- sk->sk_state = TCP_CLOSE;
+ sk_set_state(sk, TCP_CLOSE);
sock_set_flag(sk, SOCK_DEAD);
inet_csk_destroy_sock(sk);
}
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 1803116..000504f 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -283,8 +283,6 @@
#include <asm/ioctls.h>
#include <net/busy_poll.h>

-#include <trace/events/tcp.h>
-
struct percpu_counter tcp_orphan_count;
EXPORT_SYMBOL_GPL(tcp_orphan_count);

@@ -2040,8 +2038,6 @@ void tcp_set_state(struct sock *sk, int state)
{
int oldstate = sk->sk_state;

- trace_tcp_set_state(sk, oldstate, state);
-
switch (state) {
case TCP_ESTABLISHED:
if (oldstate != TCP_ESTABLISHED)
--
1.8.3.1