kernel-fxtec-pro1x/kernel/trace/trace_export.c
Steven Rostedt 770cb24345 tracing: add format files for ftrace default entries
Impact: allow user apps to read binary format of basic ftrace entries

Currently, only defined raw events export their formats so a binary
reader can parse them. There's no reason that the default ftrace entries
can't export their formats.

This patch adds a subsystem called "ftrace" in the events directory
that includes the ftrace entries for basic ftrace recorded items.

These only have three files in the events directory:

 type             : printf
 available_types  : printf
 format           : format for the event entry

For example:

 # cat /debug/tracing/events/ftrace/wakeup/format
name: wakeup
ID: 3
format:
        field:unsigned char type;       offset:0;       size:1;
        field:unsigned char flags;      offset:1;       size:1;
        field:unsigned char preempt_count;      offset:2;       size:1;
        field:int pid;  offset:4;       size:4;
        field:int tgid; offset:8;       size:4;

        field:unsigned int prev_pid;    offset:12;      size:4;
        field:unsigned char prev_prio;  offset:16;      size:1;
        field:unsigned char prev_state; offset:17;      size:1;
        field:unsigned int next_pid;    offset:20;      size:4;
        field:unsigned char next_prio;  offset:24;      size:1;
        field:unsigned char next_state; offset:25;      size:1;
        field:unsigned int next_cpu;    offset:28;      size:4;

print fmt: "%u:%u:%u  ==+ %u:%u:%u [%03u]"

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
2009-03-05 21:46:44 -05:00

81 lines
1.9 KiB
C

/*
* trace_export.c - export basic ftrace utilities to user space
*
* Copyright (C) 2009 Steven Rostedt <srostedt@redhat.com>
*/
#include <linux/stringify.h>
#include <linux/kallsyms.h>
#include <linux/seq_file.h>
#include <linux/debugfs.h>
#include <linux/uaccess.h>
#include <linux/ftrace.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/fs.h>
#include "trace_output.h"
#include "trace_format.h"
#undef TRACE_FIELD_ZERO_CHAR
#define TRACE_FIELD_ZERO_CHAR(item) \
ret = trace_seq_printf(s, "\tfield: char " #item ";\t" \
"offset:%lu;\tsize:0;\n", \
offsetof(typeof(field), item)); \
if (!ret) \
return 0;
#undef TPRAWFMT
#define TPRAWFMT(args...) args
#undef TRACE_EVENT_FORMAT
#define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt) \
static int \
ftrace_format_##call(struct trace_seq *s) \
{ \
struct args field; \
int ret; \
\
tstruct; \
\
trace_seq_printf(s, "\nprint fmt: \"%s\"\n", tpfmt); \
\
return ret; \
}
#include "trace_event_types.h"
#undef TRACE_ZERO_CHAR
#define TRACE_ZERO_CHAR(arg)
#undef TRACE_FIELD
#define TRACE_FIELD(type, item, assign)\
entry->item = assign;
#undef TRACE_FIELD
#define TRACE_FIELD(type, item, assign)\
entry->item = assign;
#undef TPCMD
#define TPCMD(cmd...) cmd
#undef TRACE_ENTRY
#define TRACE_ENTRY entry
#undef TRACE_FIELD_SPECIAL
#define TRACE_FIELD_SPECIAL(type_item, item, cmd) \
cmd;
#undef TRACE_EVENT_FORMAT
#define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt) \
\
static struct ftrace_event_call __used \
__attribute__((__aligned__(4))) \
__attribute__((section("_ftrace_events"))) event_##call = { \
.name = #call, \
.id = proto, \
.system = __stringify(TRACE_SYSTEM), \
.show_format = ftrace_format_##call, \
}
#include "trace_event_types.h"