aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/oprofile/oprofile_files.c
blob: ee2cfce358b9810b5d1f06e28d18e86e1dec0a98 (plain) (blame)
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
189
190
191
192
193
194
195
196
197
198
199
200
201
/**
 * @file oprofile_files.c
 *
 * @remark Copyright 2002 OProfile authors
 * @remark Read the file COPYING
 *
 * @author John Levon <levon@movementarian.org>
 */

#include <linux/fs.h>
#include <linux/oprofile.h>
#include <linux/jiffies.h>

#include "event_buffer.h"
#include "oprofile_stats.h"
#include "oprof.h"

#define BUFFER_SIZE_DEFAULT		131072
#define CPU_BUFFER_SIZE_DEFAULT		8192
#define BUFFER_WATERSHED_DEFAULT	32768	/* FIXME: tune */
#define TIME_SLICE_DEFAULT		1

unsigned long oprofile_buffer_size;
unsigned long oprofile_cpu_buffer_size;
unsigned long oprofile_buffer_watershed;
unsigned long oprofile_time_slice;

#ifdef CONFIG_OPROFILE_EVENT_MULTIPLEX

static ssize_t timeout_read(struct file *file, char __user *buf,
		size_t count, loff_t *offset)
{
	return oprofilefs_ulong_to_user(jiffies_to_msecs(oprofile_time_slice),
					buf, count, offset);
}


static ssize_t timeout_write(struct file *file, char const __user *buf,
		size_t count, loff_t *offset)
{
	unsigned long val;
	int retval;

	if (*offset)
		return -EINVAL;

	retval = oprofilefs_ulong_from_user(&val, buf, count);
	if (retval <= 0)
		return retval;

	retval = oprofile_set_timeout(val);

	if (retval)
		return retval;
	return count;
}


static const struct file_operations timeout_fops = {
	.read		= timeout_read,
	.write		= timeout_write,
	.llseek		= default_llseek,
};

#endif


static ssize_t depth_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
{
	return oprofilefs_ulong_to_user(oprofile_backtrace_depth, buf, count,
					offset);
}


static ssize_t depth_write(struct file *file, char const __user *buf, size_t count, loff_t *offset)
{
	unsigned long val;
	int retval;

	if (*offset)
		return -EINVAL;

	if (!oprofile_ops.backtrace)
		return -EINVAL;

	retval = oprofilefs_ulong_from_user(&val, buf, count);
	if (retval <= 0)
		return retval;

	retval = oprofile_set_ulong(&oprofile_backtrace_depth, val);
	if (retval)
		return retval;

	return count;
}


static const struct file_operations depth_fops = {
	.read		= depth_read,
	.write		= depth_write,
	.llseek		= default_llseek,
};


static ssize_t pointer_size_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
{
	return oprofilefs_ulong_to_user(sizeof(void *), buf, count, offset);
}


static const struct file_operations pointer_size_fops = {
	.read		= pointer_size_read,
	.llseek		= default_llseek,
};


static ssize_t cpu_type_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
{
	return oprofilefs_str_to_user(oprofile_ops.cpu_type, buf, count, offset);
}


static const struct file_operations cpu_type_fops = {
	.read		= cpu_type_read,
	.llseek		= default_llseek,
};


static ssize_t enable_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
{
	return oprofilefs_ulong_to_user(oprofile_started, buf, count, offset);
}


static ssize_t enable_write(struct file *file, char const __user *buf, size_t count, loff_t *offset)
{
	unsigned long val;
	int retval;

	if (*offset)
		return -EINVAL;

	retval = oprofilefs_ulong_from_user(&val, buf, count);
	if (retval <= 0)
		return retval;

	retval = 0;
	if (val)
		retval = oprofile_start();
	else
		oprofile_stop();

	if (retval)
		return retval;
	return count;
}


static const struct file_operations enable_fops = {
	.read		= enable_read,
	.write		= enable_write,
	.llseek		= default_llseek,
};


static ssize_t dump_write(struct file *file, char const __user *buf, size_t count, loff_t *offset)
{
	wake_up_buffer_waiter();
	return count;
}


static const struct file_operations dump_fops = {
	.write		= dump_write,
	.llseek		= noop_llseek,
};

void oprofile_create_files(struct dentry *root)
{
	/* reinitialize default values */
	oprofile_buffer_size =		BUFFER_SIZE_DEFAULT;
	oprofile_cpu_buffer_size =	CPU_BUFFER_SIZE_DEFAULT;
	oprofile_buffer_watershed =	BUFFER_WATERSHED_DEFAULT;
	oprofile_time_slice =		msecs_to_jiffies(TIME_SLICE_DEFAULT);

	oprofilefs_create_file(root, "enable", &enable_fops);
	oprofilefs_create_file_perm(root, "dump", &dump_fops, 0666);
	oprofilefs_create_file(root, "buffer", &event_buffer_fops);
	oprofilefs_create_ulong(root, "buffer_size", &oprofile_buffer_size);
	oprofilefs_create_ulong(root, "buffer_watershed", &oprofile_buffer_watershed);
	oprofilefs_create_ulong(root, "cpu_buffer_size", &oprofile_cpu_buffer_size);
	oprofilefs_create_file(root, "cpu_type", &cpu_type_fops);
	oprofilefs_create_file(root, "backtrace_depth", &depth_fops);
	oprofilefs_create_file(root, "pointer_size", &pointer_size_fops);
#ifdef CONFIG_OPROFILE_EVENT_MULTIPLEX
	oprofilefs_create_file(root, "time_slice", &timeout_fops);
#endif
	oprofile_create_stats_files(root);
	if (oprofile_ops.create_files)
		oprofile_ops.create_files(root);
}