aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/oprofile/oprofile_files.c
blob: d8201998b0b7f8d93b5b7f1a654851374256dff9 (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
/**
 * @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 "event_buffer.h"
#include "oprofile_stats.h"
#include "oprof.h"

#define FS_BUFFER_SIZE_DEFAULT		131072
#define FS_CPU_BUFFER_SIZE_DEFAULT	8192
#define FS_BUFFER_WATERSHED_DEFAULT	32768	/* FIXME: tune */

unsigned long fs_buffer_size;
unsigned long fs_cpu_buffer_size;
unsigned long fs_buffer_watershed;

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

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

	retval = oprofile_set_backtrace(val);

	if (retval)
		return retval;
	return count;
}


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


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,
};


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,
};


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)
		return retval;

	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,
};


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,
};

void oprofile_create_files(struct super_block *sb, struct dentry *root)
{
	/* reinitialize default values */
	fs_buffer_size =	FS_BUFFER_SIZE_DEFAULT;
	fs_cpu_buffer_size =	FS_CPU_BUFFER_SIZE_DEFAULT;
	fs_buffer_watershed =	FS_BUFFER_WATERSHED_DEFAULT;

	oprofilefs_create_file(sb, root, "enable", &enable_fops);
	oprofilefs_create_file_perm(sb, root, "dump", &dump_fops, 0666);
	oprofilefs_create_file(sb, root, "buffer", &event_buffer_fops);
	oprofilefs_create_ulong(sb, root, "buffer_size", &fs_buffer_size);
	oprofilefs_create_ulong(sb, root, "buffer_watershed", &fs_buffer_watershed);
	oprofilefs_create_ulong(sb, root, "cpu_buffer_size", &fs_cpu_buffer_size);
	oprofilefs_create_file(sb, root, "cpu_type", &cpu_type_fops);
	oprofilefs_create_file(sb, root, "backtrace_depth", &depth_fops);
	oprofilefs_create_file(sb, root, "pointer_size", &pointer_size_fops);
	oprofile_create_stats_files(sb, root);
	if (oprofile_ops.create_files)
		oprofile_ops.create_files(sb, root);
}