blob: e5162a64018b58e6f7133eef49a55fb652f89450 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
|
/**
* @file oprof.c
*
* @remark Copyright 2002 OProfile authors
* @remark Read the file COPYING
*
* @author John Levon <levon@movementarian.org>
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/oprofile.h>
#include <linux/moduleparam.h>
#include <asm/mutex.h>
#include "oprof.h"
#include "event_buffer.h"
#include "cpu_buffer.h"
#include "buffer_sync.h"
#include "oprofile_stats.h"
struct oprofile_operations oprofile_ops;
unsigned long oprofile_started;
unsigned long backtrace_depth;
static unsigned long is_setup;
static DEFINE_MUTEX(start_mutex);
/* timer
0 - use performance monitoring hardware if available
1 - use the timer int mechanism regardless
*/
static int timer = 0;
int oprofile_setup(void)
{
int err;
mutex_lock(&start_mutex);
if ((err = alloc_cpu_buffers()))
goto out;
if ((err = alloc_event_buffer()))
goto out1;
if (oprofile_ops.setup && (err = oprofile_ops.setup()))
goto out2;
/* Note even though this starts part of the
* profiling overhead, it's necessary to prevent
* us missing task deaths and eventually oopsing
* when trying to process the event buffer.
*/
if ((err = sync_start()))
goto out3;
is_setup = 1;
mutex_unlock(&start_mutex);
return 0;
out3:
if (oprofile_ops.shutdown)
oprofile_ops.shutdown();
out2:
free_event_buffer();
out1:
free_cpu_buffers();
out:
mutex_unlock(&start_mutex);
return err;
}
/* Actually start profiling (echo 1>/dev/oprofile/enable) */
int oprofile_start(void)
{
int err = -EINVAL;
mutex_lock(&start_mutex);
if (!is_setup)
goto out;
err = 0;
if (oprofile_started)
goto out;
oprofile_reset_stats();
if ((err = oprofile_ops.start()))
goto out;
oprofile_started = 1;
out:
mutex_unlock(&start_mutex);
return err;
}
/* echo 0>/dev/oprofile/enable */
void oprofile_stop(void)
{
mutex_lock(&start_mutex);
if (!oprofile_started)
goto out;
oprofile_ops.stop();
oprofile_started = 0;
/* wake up the daemon to read what remains */
wake_up_buffer_waiter();
out:
mutex_unlock(&start_mutex);
}
void oprofile_shutdown(void)
{
mutex_lock(&start_mutex);
sync_stop();
if (oprofile_ops.shutdown)
oprofile_ops.shutdown();
is_setup = 0;
free_event_buffer();
free_cpu_buffers();
mutex_unlock(&start_mutex);
}
int oprofile_set_backtrace(unsigned long val)
{
int err = 0;
mutex_lock(&start_mutex);
if (oprofile_started) {
err = -EBUSY;
goto out;
}
if (!oprofile_ops.backtrace) {
err = -EINVAL;
goto out;
}
backtrace_depth = val;
out:
mutex_unlock(&start_mutex);
return err;
}
static int __init oprofile_init(void)
{
int err;
err = oprofile_arch_init(&oprofile_ops);
if (err < 0 || timer) {
printk(KERN_INFO "oprofile: using timer interrupt.\n");
oprofile_timer_init(&oprofile_ops);
}
err = oprofilefs_register();
if (err)
oprofile_arch_exit();
return err;
}
static void __exit oprofile_exit(void)
{
oprofilefs_unregister();
oprofile_arch_exit();
}
module_init(oprofile_init);
module_exit(oprofile_exit);
module_param_named(timer, timer, int, 0644);
MODULE_PARM_DESC(timer, "force use of timer interrupt");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("John Levon <levon@movementarian.org>");
MODULE_DESCRIPTION("OProfile system profiler");
|
