tracing: add ftrace headers to event format files

This patch includes the ftrace header to the event formats files:

 # cat /debug/tracing/events/sched/sched_switch/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:pid_t prev_pid;   offset:12;      size:4;
        field:int prev_prio;    offset:16;      size:4;
        field special:char next_comm[TASK_COMM_LEN];    offset:20;      size:16;
        field:pid_t next_pid;   offset:36;      size:4;
        field:int next_prio;    offset:40;      size:4;

A blank line is used as a deliminator between the ftrace header and the
trace point fields.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
This commit is contained in:
Steven Rostedt 2009-03-02 15:03:01 -05:00
parent 981d081ec8
commit 91729ef966

View file

@ -13,7 +13,7 @@
#include <linux/module.h>
#include <linux/ctype.h>
#include "trace.h"
#include "trace_output.h"
#define TRACE_SYSTEM "TRACE_SYSTEM"
@ -447,6 +447,28 @@ event_available_types_read(struct file *filp, char __user *ubuf, size_t cnt,
return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
}
#undef FIELD
#define FIELD(type, name) \
#type, #name, offsetof(typeof(field), name), sizeof(field.name)
static int trace_write_header(struct trace_seq *s)
{
struct trace_entry field;
/* struct trace_entry */
return trace_seq_printf(s,
"\tfield:%s %s;\toffset:%lu;\tsize:%lu;\n"
"\tfield:%s %s;\toffset:%lu;\tsize:%lu;\n"
"\tfield:%s %s;\toffset:%lu;\tsize:%lu;\n"
"\tfield:%s %s;\toffset:%lu;\tsize:%lu;\n"
"\tfield:%s %s;\toffset:%lu;\tsize:%lu;\n"
"\n",
FIELD(unsigned char, type),
FIELD(unsigned char, flags),
FIELD(unsigned char, preempt_count),
FIELD(int, pid),
FIELD(int, tgid));
}
static ssize_t
event_format_read(struct file *filp, char __user *ubuf, size_t cnt,
loff_t *ppos)
@ -465,6 +487,9 @@ event_format_read(struct file *filp, char __user *ubuf, size_t cnt,
if (*ppos)
return 0;
/* If this fails, so will the show_format. */
trace_write_header(s);
r = call->show_format(s);
if (!r) {
/*