Re: [PATCH net-next 1/3] net:tracepoint: replace tcp_set_state tracepoint with sock_set_state tracepoint
From: Song Liu
Date: Tue Dec 12 2017 - 20:20:12 EST
> On Dec 10, 2017, at 7:31 AM, Yafang Shao <laoar.shao@xxxxxxxxx> wrote:
>
> 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))
Please include Steven's fix to export names to user space:
https://patchwork.kernel.org/patch/10052201/
> 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);
These two functions are short. Can we keep this in sock.h?
Thanks,
Song
> +
> 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
>