tcp: Export to userspace the TCP state names for the trace events

The TCP trace events (specifically tcp_set_state), maps emums to symbol
names via __print_symbolic(). But this only works for reading trace events
from the tracefs trace files. If perf or trace-cmd were to record these
events, the event format file does not convert the enum names into numbers,
and you get something like:

__print_symbolic(REC->oldstate,
    { TCP_ESTABLISHED, "TCP_ESTABLISHED" },
    { TCP_SYN_SENT, "TCP_SYN_SENT" },
    { TCP_SYN_RECV, "TCP_SYN_RECV" },
    { TCP_FIN_WAIT1, "TCP_FIN_WAIT1" },
    { TCP_FIN_WAIT2, "TCP_FIN_WAIT2" },
    { TCP_TIME_WAIT, "TCP_TIME_WAIT" },
    { TCP_CLOSE, "TCP_CLOSE" },
    { TCP_CLOSE_WAIT, "TCP_CLOSE_WAIT" },
    { TCP_LAST_ACK, "TCP_LAST_ACK" },
    { TCP_LISTEN, "TCP_LISTEN" },
    { TCP_CLOSING, "TCP_CLOSING" },
    { TCP_NEW_SYN_RECV, "TCP_NEW_SYN_RECV" })

Where trace-cmd and perf do not know the values of those enums.

Use the TRACE_DEFINE_ENUM() macros that will have the trace events convert
the enum strings into their values at system boot. This will allow perf and
trace-cmd to see actual numbers and not enums:

__print_symbolic(REC->oldstate,
    { 1, "TCP_ESTABLISHED" },
    { 2, "TCP_SYN_SENT" },
    { 3, "TCP_SYN_RECV" },
    { 4, "TCP_FIN_WAIT1" },
    { 5, "TCP_FIN_WAIT2" },
    { 6, "TCP_TIME_WAIT" },
    { 7, "TCP_CLOSE" },
    { 8, "TCP_CLOSE_WAIT" },
    { 9, "TCP_LAST_ACK" },
    { 10, "TCP_LISTEN" },
    { 11, "TCP_CLOSING" },
    { 12, "TCP_NEW_SYN_RECV" })

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Steven Rostedt (VMware) 2017-12-20 11:12:50 +08:00 committed by David S. Miller
parent 9ee1942cb3
commit d7b850a7de
1 changed files with 28 additions and 13 deletions

View File

@ -9,21 +9,36 @@
#include <linux/tracepoint.h>
#include <net/ipv6.h>
#define tcp_state_names \
EM(TCP_ESTABLISHED) \
EM(TCP_SYN_SENT) \
EM(TCP_SYN_RECV) \
EM(TCP_FIN_WAIT1) \
EM(TCP_FIN_WAIT2) \
EM(TCP_TIME_WAIT) \
EM(TCP_CLOSE) \
EM(TCP_CLOSE_WAIT) \
EM(TCP_LAST_ACK) \
EM(TCP_LISTEN) \
EM(TCP_CLOSING) \
EMe(TCP_NEW_SYN_RECV) \
/* enums need to be exported to user space */
#undef EM
#undef EMe
#define EM(a) TRACE_DEFINE_ENUM(a);
#define EMe(a) TRACE_DEFINE_ENUM(a);
tcp_state_names
#undef EM
#undef EMe
#define EM(a) tcp_state_name(a),
#define EMe(a) tcp_state_name(a)
#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))
__print_symbolic(val, tcp_state_names)
/*
* tcp event with arguments sk and skb