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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 | /** * @file oprof.c * * @remark Copyright 2002 OProfile authors * @remark Read the file COPYING * * @author John Levon <levon@movementarian.org> */ #include <linux/kernel.h> #include <linux/module.h> #include <linux/init.h> #include <linux/oprofile.h> #include <linux/moduleparam.h> #include <linux/workqueue.h> #include <linux/time.h> #include <linux/mutex.h> #include "oprof.h" #include "event_buffer.h" #include "cpu_buffer.h" #include "buffer_sync.h" #include "oprofile_stats.h" struct oprofile_operations oprofile_ops; unsigned long oprofile_started; unsigned long oprofile_backtrace_depth; static unsigned long is_setup; static DEFINE_MUTEX(start_mutex); /* timer 0 - use performance monitoring hardware if available 1 - use the timer int mechanism regardless */ static int timer = 0; int oprofile_setup(void) { int err; mutex_lock(&start_mutex); if ((err = alloc_cpu_buffers())) goto out; if ((err = alloc_event_buffer())) goto out1; if (oprofile_ops.setup && (err = oprofile_ops.setup())) goto out2; /* Note even though this starts part of the * profiling overhead, it's necessary to prevent * us missing task deaths and eventually oopsing * when trying to process the event buffer. */ if (oprofile_ops.sync_start) { int sync_ret = oprofile_ops.sync_start(); switch (sync_ret) { case 0: goto post_sync; case 1: goto do_generic; case -1: goto out3; default: goto out3; } } do_generic: if ((err = sync_start())) goto out3; post_sync: is_setup = 1; mutex_unlock(&start_mutex); return 0; out3: if (oprofile_ops.shutdown) oprofile_ops.shutdown(); out2: free_event_buffer(); out1: free_cpu_buffers(); out: mutex_unlock(&start_mutex); return err; } #ifdef [31mCONFIG_OPROFILE_EVENT_MULTIPLEX[0m static void switch_worker(struct work_struct *work); static DECLARE_DELAYED_WORK(switch_work, switch_worker); static void start_switch_worker(void) { if (oprofile_ops.switch_events) schedule_delayed_work(&switch_work, oprofile_time_slice); } static void stop_switch_worker(void) { cancel_delayed_work_sync(&switch_work); } static void switch_worker(struct work_struct *work) { if (oprofile_ops.switch_events()) return; atomic_inc(&oprofile_stats.multiplex_counter); start_switch_worker(); } /* User inputs in ms, converts to jiffies */ int oprofile_set_timeout(unsigned long val_msec) { int err = 0; unsigned long time_slice; mutex_lock(&start_mutex); if (oprofile_started) { err = -EBUSY; goto out; } if (!oprofile_ops.switch_events) { err = -EINVAL; goto out; } time_slice = msecs_to_jiffies(val_msec); if (time_slice == MAX_JIFFY_OFFSET) { err = -EINVAL; goto out; } oprofile_time_slice = time_slice; out: mutex_unlock(&start_mutex); return err; } #else static inline void start_switch_worker(void) { } static inline void stop_switch_worker(void) { } #endif /* Actually start profiling (echo 1>/dev/oprofile/enable) */ int oprofile_start(void) { int err = -EINVAL; mutex_lock(&start_mutex); if (!is_setup) goto out; err = 0; if (oprofile_started) goto out; oprofile_reset_stats(); if ((err = oprofile_ops.start())) goto out; start_switch_worker(); oprofile_started = 1; out: mutex_unlock(&start_mutex); return err; } /* echo 0>/dev/oprofile/enable */ void oprofile_stop(void) { mutex_lock(&start_mutex); if (!oprofile_started) goto out; oprofile_ops.stop(); oprofile_started = 0; stop_switch_worker(); /* wake up the daemon to read what remains */ wake_up_buffer_waiter(); out: mutex_unlock(&start_mutex); } void oprofile_shutdown(void) { mutex_lock(&start_mutex); if (oprofile_ops.sync_stop) { int sync_ret = oprofile_ops.sync_stop(); switch (sync_ret) { case 0: goto post_sync; case 1: goto do_generic; default: goto post_sync; } } do_generic: sync_stop(); post_sync: if (oprofile_ops.shutdown) oprofile_ops.shutdown(); is_setup = 0; free_event_buffer(); free_cpu_buffers(); mutex_unlock(&start_mutex); } int oprofile_set_ulong(unsigned long *addr, unsigned long val) { int err = -EBUSY; mutex_lock(&start_mutex); if (!oprofile_started) { *addr = val; err = 0; } mutex_unlock(&start_mutex); return err; } static int timer_mode; static int __init oprofile_init(void) { int err; /* always init architecture to setup backtrace support */ timer_mode = 0; err = oprofile_arch_init(&oprofile_ops); if (!err) { if (!timer && !oprofilefs_register()) return 0; oprofile_arch_exit(); } /* setup timer mode: */ timer_mode = 1; /* no nmi timer mode if oprofile.timer is set */ if (timer || op_nmi_timer_init(&oprofile_ops)) { err = oprofile_timer_init(&oprofile_ops); if (err) return err; } return oprofilefs_register(); } static void __exit oprofile_exit(void) { oprofilefs_unregister(); if (!timer_mode) oprofile_arch_exit(); } module_init(oprofile_init); module_exit(oprofile_exit); module_param_named(timer, timer, int, 0644); MODULE_PARM_DESC(timer, "force use of timer interrupt"); MODULE_LICENSE("GPL"); MODULE_AUTHOR("John Levon <levon@movementarian.org>"); MODULE_DESCRIPTION("OProfile system profiler"); |