mirror of
https://github.com/torvalds/linux
synced 2024-11-05 18:23:50 +00:00
3efb5f21a3
The creation of tracing files and directories is for the most part encapsulated in helper functions in trace.c. Other files do not need to include debugfs.h or fs.h, as they may have needed to in the past. Remove them from the files that do not need them. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
99 lines
2.2 KiB
C
99 lines
2.2 KiB
C
/*
|
|
* nop tracer
|
|
*
|
|
* Copyright (C) 2008 Steven Noonan <steven@uplinklabs.net>
|
|
*
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/ftrace.h>
|
|
|
|
#include "trace.h"
|
|
|
|
/* Our two options */
|
|
enum {
|
|
TRACE_NOP_OPT_ACCEPT = 0x1,
|
|
TRACE_NOP_OPT_REFUSE = 0x2
|
|
};
|
|
|
|
/* Options for the tracer (see trace_options file) */
|
|
static struct tracer_opt nop_opts[] = {
|
|
/* Option that will be accepted by set_flag callback */
|
|
{ TRACER_OPT(test_nop_accept, TRACE_NOP_OPT_ACCEPT) },
|
|
/* Option that will be refused by set_flag callback */
|
|
{ TRACER_OPT(test_nop_refuse, TRACE_NOP_OPT_REFUSE) },
|
|
{ } /* Always set a last empty entry */
|
|
};
|
|
|
|
static struct tracer_flags nop_flags = {
|
|
/* You can check your flags value here when you want. */
|
|
.val = 0, /* By default: all flags disabled */
|
|
.opts = nop_opts
|
|
};
|
|
|
|
static struct trace_array *ctx_trace;
|
|
|
|
static void start_nop_trace(struct trace_array *tr)
|
|
{
|
|
/* Nothing to do! */
|
|
}
|
|
|
|
static void stop_nop_trace(struct trace_array *tr)
|
|
{
|
|
/* Nothing to do! */
|
|
}
|
|
|
|
static int nop_trace_init(struct trace_array *tr)
|
|
{
|
|
ctx_trace = tr;
|
|
start_nop_trace(tr);
|
|
return 0;
|
|
}
|
|
|
|
static void nop_trace_reset(struct trace_array *tr)
|
|
{
|
|
stop_nop_trace(tr);
|
|
}
|
|
|
|
/* It only serves as a signal handler and a callback to
|
|
* accept or refuse tthe setting of a flag.
|
|
* If you don't implement it, then the flag setting will be
|
|
* automatically accepted.
|
|
*/
|
|
static int nop_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set)
|
|
{
|
|
/*
|
|
* Note that you don't need to update nop_flags.val yourself.
|
|
* The tracing Api will do it automatically if you return 0
|
|
*/
|
|
if (bit == TRACE_NOP_OPT_ACCEPT) {
|
|
printk(KERN_DEBUG "nop_test_accept flag set to %d: we accept."
|
|
" Now cat trace_options to see the result\n",
|
|
set);
|
|
return 0;
|
|
}
|
|
|
|
if (bit == TRACE_NOP_OPT_REFUSE) {
|
|
printk(KERN_DEBUG "nop_test_refuse flag set to %d: we refuse."
|
|
"Now cat trace_options to see the result\n",
|
|
set);
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
struct tracer nop_trace __read_mostly =
|
|
{
|
|
.name = "nop",
|
|
.init = nop_trace_init,
|
|
.reset = nop_trace_reset,
|
|
#ifdef CONFIG_FTRACE_SELFTEST
|
|
.selftest = trace_selftest_startup_nop,
|
|
#endif
|
|
.flags = &nop_flags,
|
|
.set_flag = nop_set_flag,
|
|
.allow_instances = true,
|
|
};
|
|
|