ccf099e684a46e90e53bcb17ad72536cdc42a4de
[linux-2.6.git] / drivers / oprofile / oprofile_files.c
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 #include <linux/jiffies.h>
13
14 #include "event_buffer.h"
15 #include "oprofile_stats.h"
16 #include "oprof.h"
17
18 #define BUFFER_SIZE_DEFAULT             131072
19 #define CPU_BUFFER_SIZE_DEFAULT         8192
20 #define BUFFER_WATERSHED_DEFAULT        32768   /* FIXME: tune */
21 #define TIME_SLICE_DEFAULT              1
22
23 unsigned long oprofile_buffer_size;
24 unsigned long oprofile_cpu_buffer_size;
25 unsigned long oprofile_buffer_watershed;
26 unsigned long oprofile_time_slice;
27
28 #ifdef CONFIG_OPROFILE_EVENT_MULTIPLEX
29
30 static ssize_t timeout_read(struct file *file, char __user *buf,
31                 size_t count, loff_t *offset)
32 {
33         return oprofilefs_ulong_to_user(jiffies_to_msecs(oprofile_time_slice),
34                                         buf, count, offset);
35 }
36
37
38 static ssize_t timeout_write(struct file *file, char const __user *buf,
39                 size_t count, loff_t *offset)
40 {
41         unsigned long val;
42         int retval;
43
44         if (*offset)
45                 return -EINVAL;
46
47         retval = oprofilefs_ulong_from_user(&val, buf, count);
48         if (retval)
49                 return retval;
50
51         retval = oprofile_set_timeout(val);
52
53         if (retval)
54                 return retval;
55         return count;
56 }
57
58
59 static const struct file_operations timeout_fops = {
60         .read           = timeout_read,
61         .write          = timeout_write,
62 };
63
64 #endif
65
66
67 static ssize_t depth_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
68 {
69         return oprofilefs_ulong_to_user(oprofile_backtrace_depth, buf, count,
70                                         offset);
71 }
72
73
74 static ssize_t depth_write(struct file *file, char const __user *buf, size_t count, loff_t *offset)
75 {
76         unsigned long val;
77         int retval;
78
79         if (*offset)
80                 return -EINVAL;
81
82         if (!oprofile_ops.backtrace)
83                 return -EINVAL;
84
85         retval = oprofilefs_ulong_from_user(&val, buf, count);
86         if (retval)
87                 return retval;
88
89         retval = oprofile_set_ulong(&oprofile_backtrace_depth, val);
90         if (retval)
91                 return retval;
92
93         return count;
94 }
95
96
97 static const struct file_operations depth_fops = {
98         .read           = depth_read,
99         .write          = depth_write
100 };
101
102
103 static ssize_t pointer_size_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
104 {
105         return oprofilefs_ulong_to_user(sizeof(void *), buf, count, offset);
106 }
107
108
109 static const struct file_operations pointer_size_fops = {
110         .read           = pointer_size_read,
111 };
112
113
114 static ssize_t cpu_type_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
115 {
116         return oprofilefs_str_to_user(oprofile_ops.cpu_type, buf, count, offset);
117 }
118
119
120 static const struct file_operations cpu_type_fops = {
121         .read           = cpu_type_read,
122 };
123
124
125 static ssize_t enable_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
126 {
127         return oprofilefs_ulong_to_user(oprofile_started, buf, count, offset);
128 }
129
130
131 static ssize_t enable_write(struct file *file, char const __user *buf, size_t count, loff_t *offset)
132 {
133         unsigned long val;
134         int retval;
135
136         if (*offset)
137                 return -EINVAL;
138
139         retval = oprofilefs_ulong_from_user(&val, buf, count);
140         if (retval)
141                 return retval;
142
143         if (val)
144                 retval = oprofile_start();
145         else
146                 oprofile_stop();
147
148         if (retval)
149                 return retval;
150         return count;
151 }
152
153
154 static const struct file_operations enable_fops = {
155         .read           = enable_read,
156         .write          = enable_write,
157 };
158
159
160 static ssize_t dump_write(struct file *file, char const __user *buf, size_t count, loff_t *offset)
161 {
162         wake_up_buffer_waiter();
163         return count;
164 }
165
166
167 static const struct file_operations dump_fops = {
168         .write          = dump_write,
169 };
170
171 void oprofile_create_files(struct super_block *sb, struct dentry *root)
172 {
173         /* reinitialize default values */
174         oprofile_buffer_size =          BUFFER_SIZE_DEFAULT;
175         oprofile_cpu_buffer_size =      CPU_BUFFER_SIZE_DEFAULT;
176         oprofile_buffer_watershed =     BUFFER_WATERSHED_DEFAULT;
177         oprofile_time_slice =           msecs_to_jiffies(TIME_SLICE_DEFAULT);
178
179         oprofilefs_create_file(sb, root, "enable", &enable_fops);
180         oprofilefs_create_file_perm(sb, root, "dump", &dump_fops, 0666);
181         oprofilefs_create_file(sb, root, "buffer", &event_buffer_fops);
182         oprofilefs_create_ulong(sb, root, "buffer_size", &oprofile_buffer_size);
183         oprofilefs_create_ulong(sb, root, "buffer_watershed", &oprofile_buffer_watershed);
184         oprofilefs_create_ulong(sb, root, "cpu_buffer_size", &oprofile_cpu_buffer_size);
185         oprofilefs_create_file(sb, root, "cpu_type", &cpu_type_fops);
186         oprofilefs_create_file(sb, root, "backtrace_depth", &depth_fops);
187         oprofilefs_create_file(sb, root, "pointer_size", &pointer_size_fops);
188 #ifdef CONFIG_OPROFILE_EVENT_MULTIPLEX
189         oprofilefs_create_file(sb, root, "time_slice", &timeout_fops);
190 #endif
191         oprofile_create_stats_files(sb, root);
192         if (oprofile_ops.create_files)
193                 oprofile_ops.create_files(sb, root);
194 }