| 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 <= 0) |
| 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 | .llseek = default_llseek, |
| 63 | }; |
| 64 | |
| 65 | #endif |
| 66 | |
| 67 | |
| 68 | static ssize_t depth_read(struct file *file, char __user *buf, size_t count, loff_t *offset) |
| 69 | { |
| 70 | return oprofilefs_ulong_to_user(oprofile_backtrace_depth, buf, count, |
| 71 | offset); |
| 72 | } |
| 73 | |
| 74 | |
| 75 | static ssize_t depth_write(struct file *file, char const __user *buf, size_t count, loff_t *offset) |
| 76 | { |
| 77 | unsigned long val; |
| 78 | int retval; |
| 79 | |
| 80 | if (*offset) |
| 81 | return -EINVAL; |
| 82 | |
| 83 | if (!oprofile_ops.backtrace) |
| 84 | return -EINVAL; |
| 85 | |
| 86 | retval = oprofilefs_ulong_from_user(&val, buf, count); |
| 87 | if (retval <= 0) |
| 88 | return retval; |
| 89 | |
| 90 | retval = oprofile_set_ulong(&oprofile_backtrace_depth, val); |
| 91 | if (retval) |
| 92 | return retval; |
| 93 | |
| 94 | return count; |
| 95 | } |
| 96 | |
| 97 | |
| 98 | static const struct file_operations depth_fops = { |
| 99 | .read = depth_read, |
| 100 | .write = depth_write, |
| 101 | .llseek = default_llseek, |
| 102 | }; |
| 103 | |
| 104 | |
| 105 | static ssize_t pointer_size_read(struct file *file, char __user *buf, size_t count, loff_t *offset) |
| 106 | { |
| 107 | return oprofilefs_ulong_to_user(sizeof(void *), buf, count, offset); |
| 108 | } |
| 109 | |
| 110 | |
| 111 | static const struct file_operations pointer_size_fops = { |
| 112 | .read = pointer_size_read, |
| 113 | .llseek = default_llseek, |
| 114 | }; |
| 115 | |
| 116 | |
| 117 | static ssize_t cpu_type_read(struct file *file, char __user *buf, size_t count, loff_t *offset) |
| 118 | { |
| 119 | return oprofilefs_str_to_user(oprofile_ops.cpu_type, buf, count, offset); |
| 120 | } |
| 121 | |
| 122 | |
| 123 | static const struct file_operations cpu_type_fops = { |
| 124 | .read = cpu_type_read, |
| 125 | .llseek = default_llseek, |
| 126 | }; |
| 127 | |
| 128 | |
| 129 | static ssize_t enable_read(struct file *file, char __user *buf, size_t count, loff_t *offset) |
| 130 | { |
| 131 | return oprofilefs_ulong_to_user(oprofile_started, buf, count, offset); |
| 132 | } |
| 133 | |
| 134 | |
| 135 | static ssize_t enable_write(struct file *file, char const __user *buf, size_t count, loff_t *offset) |
| 136 | { |
| 137 | unsigned long val; |
| 138 | int retval; |
| 139 | |
| 140 | if (*offset) |
| 141 | return -EINVAL; |
| 142 | |
| 143 | retval = oprofilefs_ulong_from_user(&val, buf, count); |
| 144 | if (retval <= 0) |
| 145 | return retval; |
| 146 | |
| 147 | retval = 0; |
| 148 | if (val) |
| 149 | retval = oprofile_start(); |
| 150 | else |
| 151 | oprofile_stop(); |
| 152 | |
| 153 | if (retval) |
| 154 | return retval; |
| 155 | return count; |
| 156 | } |
| 157 | |
| 158 | |
| 159 | static const struct file_operations enable_fops = { |
| 160 | .read = enable_read, |
| 161 | .write = enable_write, |
| 162 | .llseek = default_llseek, |
| 163 | }; |
| 164 | |
| 165 | |
| 166 | static ssize_t dump_write(struct file *file, char const __user *buf, size_t count, loff_t *offset) |
| 167 | { |
| 168 | wake_up_buffer_waiter(); |
| 169 | return count; |
| 170 | } |
| 171 | |
| 172 | |
| 173 | static const struct file_operations dump_fops = { |
| 174 | .write = dump_write, |
| 175 | .llseek = noop_llseek, |
| 176 | }; |
| 177 | |
| 178 | void oprofile_create_files(struct super_block *sb, struct dentry *root) |
| 179 | { |
| 180 | /* reinitialize default values */ |
| 181 | oprofile_buffer_size = BUFFER_SIZE_DEFAULT; |
| 182 | oprofile_cpu_buffer_size = CPU_BUFFER_SIZE_DEFAULT; |
| 183 | oprofile_buffer_watershed = BUFFER_WATERSHED_DEFAULT; |
| 184 | oprofile_time_slice = msecs_to_jiffies(TIME_SLICE_DEFAULT); |
| 185 | |
| 186 | oprofilefs_create_file(sb, root, "enable", &enable_fops); |
| 187 | oprofilefs_create_file_perm(sb, root, "dump", &dump_fops, 0666); |
| 188 | oprofilefs_create_file(sb, root, "buffer", &event_buffer_fops); |
| 189 | oprofilefs_create_ulong(sb, root, "buffer_size", &oprofile_buffer_size); |
| 190 | oprofilefs_create_ulong(sb, root, "buffer_watershed", &oprofile_buffer_watershed); |
| 191 | oprofilefs_create_ulong(sb, root, "cpu_buffer_size", &oprofile_cpu_buffer_size); |
| 192 | oprofilefs_create_file(sb, root, "cpu_type", &cpu_type_fops); |
| 193 | oprofilefs_create_file(sb, root, "backtrace_depth", &depth_fops); |
| 194 | oprofilefs_create_file(sb, root, "pointer_size", &pointer_size_fops); |
| 195 | #ifdef CONFIG_OPROFILE_EVENT_MULTIPLEX |
| 196 | oprofilefs_create_file(sb, root, "time_slice", &timeout_fops); |
| 197 | #endif |
| 198 | oprofile_create_stats_files(sb, root); |
| 199 | if (oprofile_ops.create_files) |
| 200 | oprofile_ops.create_files(sb, root); |
| 201 | } |