1 /* 2 * List pending timers 3 * 4 * Copyright(C) 2006, Red Hat, Inc., Ingo Molnar 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License version 2 as 8 * published by the Free Software Foundation. 9 */ 10 11 #include <linux/proc_fs.h> 12 #include <linux/module.h> 13 #include <linux/spinlock.h> 14 #include <linux/sched.h> 15 #include <linux/seq_file.h> 16 #include <linux/kallsyms.h> 17 #include <linux/nmi.h> 18 19 #include <linux/uaccess.h> 20 21 #include "tick-internal.h" 22 23 struct timer_list_iter { 24 int cpu; 25 bool second_pass; 26 u64 now; 27 }; 28 29 /* 30 * This allows printing both to /proc/timer_list and 31 * to the console (on SysRq-Q): 32 */ 33 __printf(2, 3) 34 static void SEQ_printf(struct seq_file *m, const char *fmt, ...) 35 { 36 va_list args; 37 38 va_start(args, fmt); 39 40 if (m) 41 seq_vprintf(m, fmt, args); 42 else 43 vprintk(fmt, args); 44 45 va_end(args); 46 } 47 48 static void print_name_offset(struct seq_file *m, void *sym) 49 { 50 char symname[KSYM_NAME_LEN]; 51 52 if (lookup_symbol_name((unsigned long)sym, symname) < 0) 53 SEQ_printf(m, "<%pK>", sym); 54 else 55 SEQ_printf(m, "%s", symname); 56 } 57 58 static void 59 print_timer(struct seq_file *m, struct hrtimer *taddr, struct hrtimer *timer, 60 int idx, u64 now) 61 { 62 SEQ_printf(m, " #%d: ", idx); 63 print_name_offset(m, taddr); 64 SEQ_printf(m, ", "); 65 print_name_offset(m, timer->function); 66 SEQ_printf(m, ", S:%02x", timer->state); 67 SEQ_printf(m, "\n"); 68 SEQ_printf(m, " # expires at %Lu-%Lu nsecs [in %Ld to %Ld nsecs]\n", 69 (unsigned long long)ktime_to_ns(hrtimer_get_softexpires(timer)), 70 (unsigned long long)ktime_to_ns(hrtimer_get_expires(timer)), 71 (long long)(ktime_to_ns(hrtimer_get_softexpires(timer)) - now), 72 (long long)(ktime_to_ns(hrtimer_get_expires(timer)) - now)); 73 } 74 75 static void 76 print_active_timers(struct seq_file *m, struct hrtimer_clock_base *base, 77 u64 now) 78 { 79 struct hrtimer *timer, tmp; 80 unsigned long next = 0, i; 81 struct timerqueue_node *curr; 82 unsigned long flags; 83 84 next_one: 85 i = 0; 86 87 touch_nmi_watchdog(); 88 89 raw_spin_lock_irqsave(&base->cpu_base->lock, flags); 90 91 curr = timerqueue_getnext(&base->active); 92 /* 93 * Crude but we have to do this O(N*N) thing, because 94 * we have to unlock the base when printing: 95 */ 96 while (curr && i < next) { 97 curr = timerqueue_iterate_next(curr); 98 i++; 99 } 100 101 if (curr) { 102 103 timer = container_of(curr, struct hrtimer, node); 104 tmp = *timer; 105 raw_spin_unlock_irqrestore(&base->cpu_base->lock, flags); 106 107 print_timer(m, timer, &tmp, i, now); 108 next++; 109 goto next_one; 110 } 111 raw_spin_unlock_irqrestore(&base->cpu_base->lock, flags); 112 } 113 114 static void 115 print_base(struct seq_file *m, struct hrtimer_clock_base *base, u64 now) 116 { 117 SEQ_printf(m, " .base: %pK\n", base); 118 SEQ_printf(m, " .index: %d\n", base->index); 119 120 SEQ_printf(m, " .resolution: %u nsecs\n", hrtimer_resolution); 121 122 SEQ_printf(m, " .get_time: "); 123 print_name_offset(m, base->get_time); 124 SEQ_printf(m, "\n"); 125 #ifdef CONFIG_HIGH_RES_TIMERS 126 SEQ_printf(m, " .offset: %Lu nsecs\n", 127 (unsigned long long) ktime_to_ns(base->offset)); 128 #endif 129 SEQ_printf(m, "active timers:\n"); 130 print_active_timers(m, base, now + ktime_to_ns(base->offset)); 131 } 132 133 static void print_cpu(struct seq_file *m, int cpu, u64 now) 134 { 135 struct hrtimer_cpu_base *cpu_base = &per_cpu(hrtimer_bases, cpu); 136 int i; 137 138 SEQ_printf(m, "cpu: %d\n", cpu); 139 for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) { 140 SEQ_printf(m, " clock %d:\n", i); 141 print_base(m, cpu_base->clock_base + i, now); 142 } 143 #define P(x) \ 144 SEQ_printf(m, " .%-15s: %Lu\n", #x, \ 145 (unsigned long long)(cpu_base->x)) 146 #define P_ns(x) \ 147 SEQ_printf(m, " .%-15s: %Lu nsecs\n", #x, \ 148 (unsigned long long)(ktime_to_ns(cpu_base->x))) 149 150 #ifdef CONFIG_HIGH_RES_TIMERS 151 P_ns(expires_next); 152 P(hres_active); 153 P(nr_events); 154 P(nr_retries); 155 P(nr_hangs); 156 P(max_hang_time); 157 #endif 158 #undef P 159 #undef P_ns 160 161 #ifdef CONFIG_TICK_ONESHOT 162 # define P(x) \ 163 SEQ_printf(m, " .%-15s: %Lu\n", #x, \ 164 (unsigned long long)(ts->x)) 165 # define P_ns(x) \ 166 SEQ_printf(m, " .%-15s: %Lu nsecs\n", #x, \ 167 (unsigned long long)(ktime_to_ns(ts->x))) 168 { 169 struct tick_sched *ts = tick_get_tick_sched(cpu); 170 P(nohz_mode); 171 P_ns(last_tick); 172 P(tick_stopped); 173 P(idle_jiffies); 174 P(idle_calls); 175 P(idle_sleeps); 176 P_ns(idle_entrytime); 177 P_ns(idle_waketime); 178 P_ns(idle_exittime); 179 P_ns(idle_sleeptime); 180 P_ns(iowait_sleeptime); 181 P(last_jiffies); 182 P(next_timer); 183 P_ns(idle_expires); 184 SEQ_printf(m, "jiffies: %Lu\n", 185 (unsigned long long)jiffies); 186 } 187 #endif 188 189 #undef P 190 #undef P_ns 191 SEQ_printf(m, "\n"); 192 } 193 194 #ifdef CONFIG_GENERIC_CLOCKEVENTS 195 static void 196 print_tickdevice(struct seq_file *m, struct tick_device *td, int cpu) 197 { 198 struct clock_event_device *dev = td->evtdev; 199 200 touch_nmi_watchdog(); 201 202 SEQ_printf(m, "Tick Device: mode: %d\n", td->mode); 203 if (cpu < 0) 204 SEQ_printf(m, "Broadcast device\n"); 205 else 206 SEQ_printf(m, "Per CPU device: %d\n", cpu); 207 208 SEQ_printf(m, "Clock Event Device: "); 209 if (!dev) { 210 SEQ_printf(m, "<NULL>\n"); 211 return; 212 } 213 SEQ_printf(m, "%s\n", dev->name); 214 SEQ_printf(m, " max_delta_ns: %llu\n", 215 (unsigned long long) dev->max_delta_ns); 216 SEQ_printf(m, " min_delta_ns: %llu\n", 217 (unsigned long long) dev->min_delta_ns); 218 SEQ_printf(m, " mult: %u\n", dev->mult); 219 SEQ_printf(m, " shift: %u\n", dev->shift); 220 SEQ_printf(m, " mode: %d\n", clockevent_get_state(dev)); 221 SEQ_printf(m, " next_event: %Ld nsecs\n", 222 (unsigned long long) ktime_to_ns(dev->next_event)); 223 224 SEQ_printf(m, " set_next_event: "); 225 print_name_offset(m, dev->set_next_event); 226 SEQ_printf(m, "\n"); 227 228 if (dev->set_state_shutdown) { 229 SEQ_printf(m, " shutdown: "); 230 print_name_offset(m, dev->set_state_shutdown); 231 SEQ_printf(m, "\n"); 232 } 233 234 if (dev->set_state_periodic) { 235 SEQ_printf(m, " periodic: "); 236 print_name_offset(m, dev->set_state_periodic); 237 SEQ_printf(m, "\n"); 238 } 239 240 if (dev->set_state_oneshot) { 241 SEQ_printf(m, " oneshot: "); 242 print_name_offset(m, dev->set_state_oneshot); 243 SEQ_printf(m, "\n"); 244 } 245 246 if (dev->set_state_oneshot_stopped) { 247 SEQ_printf(m, " oneshot stopped: "); 248 print_name_offset(m, dev->set_state_oneshot_stopped); 249 SEQ_printf(m, "\n"); 250 } 251 252 if (dev->tick_resume) { 253 SEQ_printf(m, " resume: "); 254 print_name_offset(m, dev->tick_resume); 255 SEQ_printf(m, "\n"); 256 } 257 258 SEQ_printf(m, " event_handler: "); 259 print_name_offset(m, dev->event_handler); 260 SEQ_printf(m, "\n"); 261 SEQ_printf(m, " retries: %lu\n", dev->retries); 262 SEQ_printf(m, "\n"); 263 } 264 265 static void timer_list_show_tickdevices_header(struct seq_file *m) 266 { 267 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST 268 print_tickdevice(m, tick_get_broadcast_device(), -1); 269 SEQ_printf(m, "tick_broadcast_mask: %*pb\n", 270 cpumask_pr_args(tick_get_broadcast_mask())); 271 #ifdef CONFIG_TICK_ONESHOT 272 SEQ_printf(m, "tick_broadcast_oneshot_mask: %*pb\n", 273 cpumask_pr_args(tick_get_broadcast_oneshot_mask())); 274 #endif 275 SEQ_printf(m, "\n"); 276 #endif 277 } 278 #endif 279 280 static inline void timer_list_header(struct seq_file *m, u64 now) 281 { 282 SEQ_printf(m, "Timer List Version: v0.8\n"); 283 SEQ_printf(m, "HRTIMER_MAX_CLOCK_BASES: %d\n", HRTIMER_MAX_CLOCK_BASES); 284 SEQ_printf(m, "now at %Ld nsecs\n", (unsigned long long)now); 285 SEQ_printf(m, "\n"); 286 } 287 288 static int timer_list_show(struct seq_file *m, void *v) 289 { 290 struct timer_list_iter *iter = v; 291 292 if (iter->cpu == -1 && !iter->second_pass) 293 timer_list_header(m, iter->now); 294 else if (!iter->second_pass) 295 print_cpu(m, iter->cpu, iter->now); 296 #ifdef CONFIG_GENERIC_CLOCKEVENTS 297 else if (iter->cpu == -1 && iter->second_pass) 298 timer_list_show_tickdevices_header(m); 299 else 300 print_tickdevice(m, tick_get_device(iter->cpu), iter->cpu); 301 #endif 302 return 0; 303 } 304 305 void sysrq_timer_list_show(void) 306 { 307 u64 now = ktime_to_ns(ktime_get()); 308 int cpu; 309 310 timer_list_header(NULL, now); 311 312 for_each_online_cpu(cpu) 313 print_cpu(NULL, cpu, now); 314 315 #ifdef CONFIG_GENERIC_CLOCKEVENTS 316 timer_list_show_tickdevices_header(NULL); 317 for_each_online_cpu(cpu) 318 print_tickdevice(NULL, tick_get_device(cpu), cpu); 319 #endif 320 return; 321 } 322 323 static void *move_iter(struct timer_list_iter *iter, loff_t offset) 324 { 325 for (; offset; offset--) { 326 iter->cpu = cpumask_next(iter->cpu, cpu_online_mask); 327 if (iter->cpu >= nr_cpu_ids) { 328 #ifdef CONFIG_GENERIC_CLOCKEVENTS 329 if (!iter->second_pass) { 330 iter->cpu = -1; 331 iter->second_pass = true; 332 } else 333 return NULL; 334 #else 335 return NULL; 336 #endif 337 } 338 } 339 return iter; 340 } 341 342 static void *timer_list_start(struct seq_file *file, loff_t *offset) 343 { 344 struct timer_list_iter *iter = file->private; 345 346 if (!*offset) 347 iter->now = ktime_to_ns(ktime_get()); 348 iter->cpu = -1; 349 iter->second_pass = false; 350 return move_iter(iter, *offset); 351 } 352 353 static void *timer_list_next(struct seq_file *file, void *v, loff_t *offset) 354 { 355 struct timer_list_iter *iter = file->private; 356 ++*offset; 357 return move_iter(iter, 1); 358 } 359 360 static void timer_list_stop(struct seq_file *seq, void *v) 361 { 362 } 363 364 static const struct seq_operations timer_list_sops = { 365 .start = timer_list_start, 366 .next = timer_list_next, 367 .stop = timer_list_stop, 368 .show = timer_list_show, 369 }; 370 371 static int __init init_timer_list_procfs(void) 372 { 373 struct proc_dir_entry *pe; 374 375 pe = proc_create_seq_private("timer_list", 0400, NULL, &timer_list_sops, 376 sizeof(struct timer_list_iter), NULL); 377 if (!pe) 378 return -ENOMEM; 379 return 0; 380 } 381 __initcall(init_timer_list_procfs); 382