tracing/ftrace: fix unexpected -EINVAL when longest tracer name is set
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / kernel / trace / trace_nop.c
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1/*
2 * nop tracer
3 *
4 * Copyright (C) 2008 Steven Noonan <steven@uplinklabs.net>
5 *
6 */
7
8#include <linux/module.h>
9#include <linux/fs.h>
10#include <linux/debugfs.h>
11#include <linux/ftrace.h>
12
13#include "trace.h"
14
15static struct trace_array *ctx_trace;
16
17static void start_nop_trace(struct trace_array *tr)
18{
19 /* Nothing to do! */
20}
21
22static void stop_nop_trace(struct trace_array *tr)
23{
24 /* Nothing to do! */
25}
26
27static void nop_trace_init(struct trace_array *tr)
28{
35cb5ed0 29 int cpu;
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30 ctx_trace = tr;
31
35cb5ed0 32 for_each_online_cpu(cpu)
3928a8a2 33 tracing_reset(tr, cpu);
35cb5ed0 34
c76f0694 35 start_nop_trace(tr);
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36}
37
38static void nop_trace_reset(struct trace_array *tr)
39{
c76f0694 40 stop_nop_trace(tr);
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41}
42
43a15386 43struct tracer nop_trace __read_mostly =
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44{
45 .name = "nop",
46 .init = nop_trace_init,
47 .reset = nop_trace_reset,
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48#ifdef CONFIG_FTRACE_SELFTEST
49 .selftest = trace_selftest_startup_nop,
50#endif
51};
52