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Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/**
2 * @file oprofile_files.c
3 *
4 * @remark Copyright 2002 OProfile authors
5 * @remark Read the file COPYING
6 *
7 * @author John Levon <levon@movementarian.org>
8 */
9
10#include <linux/fs.h>
11#include <linux/oprofile.h>
12
13#include "event_buffer.h"
14#include "oprofile_stats.h"
15#include "oprof.h"
16
17#define BUFFER_SIZE_DEFAULT 131072
18#define CPU_BUFFER_SIZE_DEFAULT 8192
19#define BUFFER_WATERSHED_DEFAULT 32768 /* FIXME: tune */
20
21unsigned long oprofile_buffer_size;
22unsigned long oprofile_cpu_buffer_size;
23unsigned long oprofile_buffer_watershed;
24
25static ssize_t depth_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
26{
27 return oprofilefs_ulong_to_user(oprofile_backtrace_depth, buf, count,
28 offset);
29}
30
31
32static ssize_t depth_write(struct file *file, char const __user *buf, size_t count, loff_t *offset)
33{
34 unsigned long val;
35 int retval;
36
37 if (*offset)
38 return -EINVAL;
39
40 retval = oprofilefs_ulong_from_user(&val, buf, count);
41 if (retval)
42 return retval;
43
44 retval = oprofile_set_backtrace(val);
45
46 if (retval)
47 return retval;
48 return count;
49}
50
51
52static const struct file_operations depth_fops = {
53 .read = depth_read,
54 .write = depth_write
55};
56
57
58static ssize_t pointer_size_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
59{
60 return oprofilefs_ulong_to_user(sizeof(void *), buf, count, offset);
61}
62
63
64static const struct file_operations pointer_size_fops = {
65 .read = pointer_size_read,
66};
67
68
69static ssize_t cpu_type_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
70{
71 return oprofilefs_str_to_user(oprofile_ops.cpu_type, buf, count, offset);
72}
73
74
75static const struct file_operations cpu_type_fops = {
76 .read = cpu_type_read,
77};
78
79
80static ssize_t enable_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
81{
82 return oprofilefs_ulong_to_user(oprofile_started, buf, count, offset);
83}
84
85
86static ssize_t enable_write(struct file *file, char const __user *buf, size_t count, loff_t *offset)
87{
88 unsigned long val;
89 int retval;
90
91 if (*offset)
92 return -EINVAL;
93
94 retval = oprofilefs_ulong_from_user(&val, buf, count);
95 if (retval)
96 return retval;
97
98 if (val)
99 retval = oprofile_start();
100 else
101 oprofile_stop();
102
103 if (retval)
104 return retval;
105 return count;
106}
107
108
109static const struct file_operations enable_fops = {
110 .read = enable_read,
111 .write = enable_write,
112};
113
114
115static ssize_t dump_write(struct file *file, char const __user *buf, size_t count, loff_t *offset)
116{
117 wake_up_buffer_waiter();
118 return count;
119}
120
121
122static const struct file_operations dump_fops = {
123 .write = dump_write,
124};
125
126void oprofile_create_files(struct super_block *sb, struct dentry *root)
127{
128 /* reinitialize default values */
129 oprofile_buffer_size = BUFFER_SIZE_DEFAULT;
130 oprofile_cpu_buffer_size = CPU_BUFFER_SIZE_DEFAULT;
131 oprofile_buffer_watershed = BUFFER_WATERSHED_DEFAULT;
132
133 oprofilefs_create_file(sb, root, "enable", &enable_fops);
134 oprofilefs_create_file_perm(sb, root, "dump", &dump_fops, 0666);
135 oprofilefs_create_file(sb, root, "buffer", &event_buffer_fops);
136 oprofilefs_create_ulong(sb, root, "buffer_size", &oprofile_buffer_size);
137 oprofilefs_create_ulong(sb, root, "buffer_watershed", &oprofile_buffer_watershed);
138 oprofilefs_create_ulong(sb, root, "cpu_buffer_size", &oprofile_cpu_buffer_size);
139 oprofilefs_create_file(sb, root, "cpu_type", &cpu_type_fops);
140 oprofilefs_create_file(sb, root, "backtrace_depth", &depth_fops);
141 oprofilefs_create_file(sb, root, "pointer_size", &pointer_size_fops);
142 oprofile_create_stats_files(sb, root);
143 if (oprofile_ops.create_files)
144 oprofile_ops.create_files(sb, root);
145}