Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /** |
| 2 | * @file oprof.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/kernel.h> |
| 11 | #include <linux/module.h> |
| 12 | #include <linux/init.h> |
| 13 | #include <linux/oprofile.h> |
| 14 | #include <linux/moduleparam.h> |
Jason Yeh | 4d4036e | 2009-07-08 13:49:38 +0200 | [diff] [blame] | 15 | #include <linux/workqueue.h> |
| 16 | #include <linux/time.h> |
Anton Blanchard | b76a06e | 2011-05-08 19:32:36 -0400 | [diff] [blame] | 17 | #include <linux/mutex.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 18 | |
| 19 | #include "oprof.h" |
| 20 | #include "event_buffer.h" |
| 21 | #include "cpu_buffer.h" |
| 22 | #include "buffer_sync.h" |
| 23 | #include "oprofile_stats.h" |
Robert Richter | c92960f | 2008-09-05 17:12:36 +0200 | [diff] [blame] | 24 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 25 | struct oprofile_operations oprofile_ops; |
| 26 | |
| 27 | unsigned long oprofile_started; |
Robert Richter | bd2172f | 2008-12-16 16:19:54 +0100 | [diff] [blame] | 28 | unsigned long oprofile_backtrace_depth; |
Robert Richter | 4c168ea | 2008-09-24 11:08:52 +0200 | [diff] [blame] | 29 | static unsigned long is_setup; |
| 30 | static DEFINE_MUTEX(start_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 31 | |
| 32 | /* timer |
| 33 | 0 - use performance monitoring hardware if available |
| 34 | 1 - use the timer int mechanism regardless |
| 35 | */ |
| 36 | static int timer = 0; |
| 37 | |
| 38 | int oprofile_setup(void) |
| 39 | { |
| 40 | int err; |
Robert Richter | c92960f | 2008-09-05 17:12:36 +0200 | [diff] [blame] | 41 | |
Markus Armbruster | 59cc185 | 2006-06-25 05:47:33 -0700 | [diff] [blame] | 42 | mutex_lock(&start_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | |
| 44 | if ((err = alloc_cpu_buffers())) |
| 45 | goto out; |
| 46 | |
| 47 | if ((err = alloc_event_buffer())) |
| 48 | goto out1; |
Robert Richter | c92960f | 2008-09-05 17:12:36 +0200 | [diff] [blame] | 49 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 50 | if (oprofile_ops.setup && (err = oprofile_ops.setup())) |
| 51 | goto out2; |
Robert Richter | c92960f | 2008-09-05 17:12:36 +0200 | [diff] [blame] | 52 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 53 | /* Note even though this starts part of the |
| 54 | * profiling overhead, it's necessary to prevent |
| 55 | * us missing task deaths and eventually oopsing |
| 56 | * when trying to process the event buffer. |
| 57 | */ |
Bob Nelson | 1474855 | 2007-07-20 21:39:53 +0200 | [diff] [blame] | 58 | if (oprofile_ops.sync_start) { |
| 59 | int sync_ret = oprofile_ops.sync_start(); |
| 60 | switch (sync_ret) { |
| 61 | case 0: |
| 62 | goto post_sync; |
| 63 | case 1: |
| 64 | goto do_generic; |
| 65 | case -1: |
| 66 | goto out3; |
| 67 | default: |
| 68 | goto out3; |
| 69 | } |
| 70 | } |
| 71 | do_generic: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 72 | if ((err = sync_start())) |
| 73 | goto out3; |
| 74 | |
Bob Nelson | 1474855 | 2007-07-20 21:39:53 +0200 | [diff] [blame] | 75 | post_sync: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 76 | is_setup = 1; |
Markus Armbruster | 59cc185 | 2006-06-25 05:47:33 -0700 | [diff] [blame] | 77 | mutex_unlock(&start_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 78 | return 0; |
Robert Richter | c92960f | 2008-09-05 17:12:36 +0200 | [diff] [blame] | 79 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 80 | out3: |
| 81 | if (oprofile_ops.shutdown) |
| 82 | oprofile_ops.shutdown(); |
| 83 | out2: |
| 84 | free_event_buffer(); |
| 85 | out1: |
| 86 | free_cpu_buffers(); |
| 87 | out: |
Markus Armbruster | 59cc185 | 2006-06-25 05:47:33 -0700 | [diff] [blame] | 88 | mutex_unlock(&start_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 89 | return err; |
| 90 | } |
| 91 | |
Jason Yeh | 4d4036e | 2009-07-08 13:49:38 +0200 | [diff] [blame] | 92 | #ifdef CONFIG_OPROFILE_EVENT_MULTIPLEX |
| 93 | |
Robert Richter | a5659d1 | 2009-06-19 16:45:34 +0200 | [diff] [blame] | 94 | static void switch_worker(struct work_struct *work); |
| 95 | static DECLARE_DELAYED_WORK(switch_work, switch_worker); |
| 96 | |
Jason Yeh | 4d4036e | 2009-07-08 13:49:38 +0200 | [diff] [blame] | 97 | static void start_switch_worker(void) |
| 98 | { |
Robert Richter | a5659d1 | 2009-06-19 16:45:34 +0200 | [diff] [blame] | 99 | if (oprofile_ops.switch_events) |
| 100 | schedule_delayed_work(&switch_work, oprofile_time_slice); |
| 101 | } |
| 102 | |
| 103 | static void stop_switch_worker(void) |
| 104 | { |
| 105 | cancel_delayed_work_sync(&switch_work); |
Jason Yeh | 4d4036e | 2009-07-08 13:49:38 +0200 | [diff] [blame] | 106 | } |
| 107 | |
| 108 | static void switch_worker(struct work_struct *work) |
| 109 | { |
Robert Richter | 1b294f5 | 2009-07-09 14:56:25 +0200 | [diff] [blame] | 110 | if (oprofile_ops.switch_events()) |
| 111 | return; |
| 112 | |
| 113 | atomic_inc(&oprofile_stats.multiplex_counter); |
| 114 | start_switch_worker(); |
Jason Yeh | 4d4036e | 2009-07-08 13:49:38 +0200 | [diff] [blame] | 115 | } |
| 116 | |
Jason Yeh | 4d4036e | 2009-07-08 13:49:38 +0200 | [diff] [blame] | 117 | /* User inputs in ms, converts to jiffies */ |
| 118 | int oprofile_set_timeout(unsigned long val_msec) |
| 119 | { |
| 120 | int err = 0; |
Robert Richter | 2051cad | 2009-07-15 15:44:18 +0200 | [diff] [blame] | 121 | unsigned long time_slice; |
Jason Yeh | 4d4036e | 2009-07-08 13:49:38 +0200 | [diff] [blame] | 122 | |
| 123 | mutex_lock(&start_mutex); |
| 124 | |
| 125 | if (oprofile_started) { |
| 126 | err = -EBUSY; |
| 127 | goto out; |
| 128 | } |
| 129 | |
| 130 | if (!oprofile_ops.switch_events) { |
| 131 | err = -EINVAL; |
| 132 | goto out; |
| 133 | } |
| 134 | |
Robert Richter | 2051cad | 2009-07-15 15:44:18 +0200 | [diff] [blame] | 135 | time_slice = msecs_to_jiffies(val_msec); |
| 136 | if (time_slice == MAX_JIFFY_OFFSET) { |
| 137 | err = -EINVAL; |
| 138 | goto out; |
| 139 | } |
| 140 | |
Robert Richter | afe1b50f | 2009-07-15 15:19:29 +0200 | [diff] [blame] | 141 | oprofile_time_slice = time_slice; |
Jason Yeh | 4d4036e | 2009-07-08 13:49:38 +0200 | [diff] [blame] | 142 | |
| 143 | out: |
| 144 | mutex_unlock(&start_mutex); |
| 145 | return err; |
| 146 | |
| 147 | } |
| 148 | |
Robert Richter | a5659d1 | 2009-06-19 16:45:34 +0200 | [diff] [blame] | 149 | #else |
| 150 | |
| 151 | static inline void start_switch_worker(void) { } |
| 152 | static inline void stop_switch_worker(void) { } |
| 153 | |
Jason Yeh | 4d4036e | 2009-07-08 13:49:38 +0200 | [diff] [blame] | 154 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 155 | |
Robert Richter | a5659d1 | 2009-06-19 16:45:34 +0200 | [diff] [blame] | 156 | /* Actually start profiling (echo 1>/dev/oprofile/enable) */ |
| 157 | int oprofile_start(void) |
| 158 | { |
| 159 | int err = -EINVAL; |
| 160 | |
| 161 | mutex_lock(&start_mutex); |
| 162 | |
| 163 | if (!is_setup) |
| 164 | goto out; |
| 165 | |
| 166 | err = 0; |
| 167 | |
| 168 | if (oprofile_started) |
| 169 | goto out; |
| 170 | |
| 171 | oprofile_reset_stats(); |
| 172 | |
| 173 | if ((err = oprofile_ops.start())) |
| 174 | goto out; |
| 175 | |
| 176 | start_switch_worker(); |
| 177 | |
| 178 | oprofile_started = 1; |
| 179 | out: |
| 180 | mutex_unlock(&start_mutex); |
| 181 | return err; |
| 182 | } |
| 183 | |
| 184 | |
| 185 | /* echo 0>/dev/oprofile/enable */ |
| 186 | void oprofile_stop(void) |
| 187 | { |
| 188 | mutex_lock(&start_mutex); |
| 189 | if (!oprofile_started) |
| 190 | goto out; |
| 191 | oprofile_ops.stop(); |
| 192 | oprofile_started = 0; |
| 193 | |
| 194 | stop_switch_worker(); |
| 195 | |
| 196 | /* wake up the daemon to read what remains */ |
| 197 | wake_up_buffer_waiter(); |
| 198 | out: |
| 199 | mutex_unlock(&start_mutex); |
| 200 | } |
| 201 | |
| 202 | |
| 203 | void oprofile_shutdown(void) |
| 204 | { |
| 205 | mutex_lock(&start_mutex); |
| 206 | if (oprofile_ops.sync_stop) { |
| 207 | int sync_ret = oprofile_ops.sync_stop(); |
| 208 | switch (sync_ret) { |
| 209 | case 0: |
| 210 | goto post_sync; |
| 211 | case 1: |
| 212 | goto do_generic; |
| 213 | default: |
| 214 | goto post_sync; |
| 215 | } |
| 216 | } |
| 217 | do_generic: |
| 218 | sync_stop(); |
| 219 | post_sync: |
| 220 | if (oprofile_ops.shutdown) |
| 221 | oprofile_ops.shutdown(); |
| 222 | is_setup = 0; |
| 223 | free_event_buffer(); |
| 224 | free_cpu_buffers(); |
| 225 | mutex_unlock(&start_mutex); |
| 226 | } |
| 227 | |
Robert Richter | 7df01d9 | 2010-10-04 21:09:36 +0200 | [diff] [blame] | 228 | int oprofile_set_ulong(unsigned long *addr, unsigned long val) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 229 | { |
Robert Richter | 7df01d9 | 2010-10-04 21:09:36 +0200 | [diff] [blame] | 230 | int err = -EBUSY; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 231 | |
Markus Armbruster | 59cc185 | 2006-06-25 05:47:33 -0700 | [diff] [blame] | 232 | mutex_lock(&start_mutex); |
Robert Richter | 7df01d9 | 2010-10-04 21:09:36 +0200 | [diff] [blame] | 233 | if (!oprofile_started) { |
| 234 | *addr = val; |
| 235 | err = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 236 | } |
Markus Armbruster | 59cc185 | 2006-06-25 05:47:33 -0700 | [diff] [blame] | 237 | mutex_unlock(&start_mutex); |
Robert Richter | 7df01d9 | 2010-10-04 21:09:36 +0200 | [diff] [blame] | 238 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 239 | return err; |
| 240 | } |
| 241 | |
| 242 | static int __init oprofile_init(void) |
| 243 | { |
| 244 | int err; |
| 245 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 246 | err = oprofile_arch_init(&oprofile_ops); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 247 | if (err < 0 || timer) { |
| 248 | printk(KERN_INFO "oprofile: using timer interrupt.\n"); |
Martin Schwidefsky | bc078e4 | 2010-03-02 16:01:10 +0100 | [diff] [blame] | 249 | err = oprofile_timer_init(&oprofile_ops); |
| 250 | if (err) |
Will Deacon | 979048e | 2010-08-29 14:51:59 -0400 | [diff] [blame] | 251 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 252 | } |
Will Deacon | 979048e | 2010-08-29 14:51:59 -0400 | [diff] [blame] | 253 | return oprofilefs_register(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 254 | } |
| 255 | |
| 256 | |
| 257 | static void __exit oprofile_exit(void) |
| 258 | { |
Martin Schwidefsky | bc078e4 | 2010-03-02 16:01:10 +0100 | [diff] [blame] | 259 | oprofile_timer_exit(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 260 | oprofilefs_unregister(); |
| 261 | oprofile_arch_exit(); |
| 262 | } |
| 263 | |
Robert Richter | c92960f | 2008-09-05 17:12:36 +0200 | [diff] [blame] | 264 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 265 | module_init(oprofile_init); |
| 266 | module_exit(oprofile_exit); |
| 267 | |
| 268 | module_param_named(timer, timer, int, 0644); |
| 269 | MODULE_PARM_DESC(timer, "force use of timer interrupt"); |
Robert Richter | c92960f | 2008-09-05 17:12:36 +0200 | [diff] [blame] | 270 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 271 | MODULE_LICENSE("GPL"); |
| 272 | MODULE_AUTHOR("John Levon <levon@movementarian.org>"); |
| 273 | MODULE_DESCRIPTION("OProfile system profiler"); |