1 /* 2 * kernel/time/timer_list.c 3 * 4 * List pending timers 5 * 6 * Copyright(C) 2006, Red Hat, Inc., Ingo Molnar 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License version 2 as 10 * published by the Free Software Foundation. 11 */ 12 13 #include <linux/proc_fs.h> 14 #include <linux/module.h> 15 #include <linux/spinlock.h> 16 #include <linux/sched.h> 17 #include <linux/seq_file.h> 18 #include <linux/kallsyms.h> 19 #include <linux/tick.h> 20 21 #include <asm/uaccess.h> 22 23 24 struct timer_list_iter { 25 int cpu; 26 bool second_pass; 27 u64 now; 28 }; 29 30 typedef void (*print_fn_t)(struct seq_file *m, unsigned int *classes); 31 32 DECLARE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases); 33 34 /* 35 * This allows printing both to /proc/timer_list and 36 * to the console (on SysRq-Q): 37 */ 38 #define SEQ_printf(m, x...) \ 39 do { \ 40 if (m) \ 41 seq_printf(m, x); \ 42 else \ 43 printk(x); \ 44 } while (0) 45 46 static void print_name_offset(struct seq_file *m, void *sym) 47 { 48 char symname[KSYM_NAME_LEN]; 49 50 if (lookup_symbol_name((unsigned long)sym, symname) < 0) 51 SEQ_printf(m, "<%pK>", sym); 52 else 53 SEQ_printf(m, "%s", symname); 54 } 55 56 static void 57 print_timer(struct seq_file *m, struct hrtimer *taddr, struct hrtimer *timer, 58 int idx, u64 now) 59 { 60 #ifdef CONFIG_TIMER_STATS 61 char tmp[TASK_COMM_LEN + 1]; 62 #endif 63 SEQ_printf(m, " #%d: ", idx); 64 print_name_offset(m, taddr); 65 SEQ_printf(m, ", "); 66 print_name_offset(m, timer->function); 67 SEQ_printf(m, ", S:%02lx", timer->state); 68 #ifdef CONFIG_TIMER_STATS 69 SEQ_printf(m, ", "); 70 print_name_offset(m, timer->start_site); 71 memcpy(tmp, timer->start_comm, TASK_COMM_LEN); 72 tmp[TASK_COMM_LEN] = 0; 73 SEQ_printf(m, ", %s/%d", tmp, timer->start_pid); 74 #endif 75 SEQ_printf(m, "\n"); 76 SEQ_printf(m, " # expires at %Lu-%Lu nsecs [in %Ld to %Ld nsecs]\n", 77 (unsigned long long)ktime_to_ns(hrtimer_get_softexpires(timer)), 78 (unsigned long long)ktime_to_ns(hrtimer_get_expires(timer)), 79 (long long)(ktime_to_ns(hrtimer_get_softexpires(timer)) - now), 80 (long long)(ktime_to_ns(hrtimer_get_expires(timer)) - now)); 81 } 82 83 static void 84 print_active_timers(struct seq_file *m, struct hrtimer_clock_base *base, 85 u64 now) 86 { 87 struct hrtimer *timer, tmp; 88 unsigned long next = 0, i; 89 struct timerqueue_node *curr; 90 unsigned long flags; 91 92 next_one: 93 i = 0; 94 raw_spin_lock_irqsave(&base->cpu_base->lock, flags); 95 96 curr = timerqueue_getnext(&base->active); 97 /* 98 * Crude but we have to do this O(N*N) thing, because 99 * we have to unlock the base when printing: 100 */ 101 while (curr && i < next) { 102 curr = timerqueue_iterate_next(curr); 103 i++; 104 } 105 106 if (curr) { 107 108 timer = container_of(curr, struct hrtimer, node); 109 tmp = *timer; 110 raw_spin_unlock_irqrestore(&base->cpu_base->lock, flags); 111 112 print_timer(m, timer, &tmp, i, now); 113 next++; 114 goto next_one; 115 } 116 raw_spin_unlock_irqrestore(&base->cpu_base->lock, flags); 117 } 118 119 static void 120 print_base(struct seq_file *m, struct hrtimer_clock_base *base, u64 now) 121 { 122 SEQ_printf(m, " .base: %pK\n", base); 123 SEQ_printf(m, " .index: %d\n", 124 base->index); 125 SEQ_printf(m, " .resolution: %Lu nsecs\n", 126 (unsigned long long)ktime_to_ns(base->resolution)); 127 SEQ_printf(m, " .get_time: "); 128 print_name_offset(m, base->get_time); 129 SEQ_printf(m, "\n"); 130 #ifdef CONFIG_HIGH_RES_TIMERS 131 SEQ_printf(m, " .offset: %Lu nsecs\n", 132 (unsigned long long) ktime_to_ns(base->offset)); 133 #endif 134 SEQ_printf(m, "active timers:\n"); 135 print_active_timers(m, base, now); 136 } 137 138 static void print_cpu(struct seq_file *m, int cpu, u64 now) 139 { 140 struct hrtimer_cpu_base *cpu_base = &per_cpu(hrtimer_bases, cpu); 141 int i; 142 143 SEQ_printf(m, "cpu: %d\n", cpu); 144 for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) { 145 SEQ_printf(m, " clock %d:\n", i); 146 print_base(m, cpu_base->clock_base + i, now); 147 } 148 #define P(x) \ 149 SEQ_printf(m, " .%-15s: %Lu\n", #x, \ 150 (unsigned long long)(cpu_base->x)) 151 #define P_ns(x) \ 152 SEQ_printf(m, " .%-15s: %Lu nsecs\n", #x, \ 153 (unsigned long long)(ktime_to_ns(cpu_base->x))) 154 155 #ifdef CONFIG_HIGH_RES_TIMERS 156 P_ns(expires_next); 157 P(hres_active); 158 P(nr_events); 159 P(nr_retries); 160 P(nr_hangs); 161 P_ns(max_hang_time); 162 #endif 163 #undef P 164 #undef P_ns 165 166 #ifdef CONFIG_TICK_ONESHOT 167 # define P(x) \ 168 SEQ_printf(m, " .%-15s: %Lu\n", #x, \ 169 (unsigned long long)(ts->x)) 170 # define P_ns(x) \ 171 SEQ_printf(m, " .%-15s: %Lu nsecs\n", #x, \ 172 (unsigned long long)(ktime_to_ns(ts->x))) 173 { 174 struct tick_sched *ts = tick_get_tick_sched(cpu); 175 P(nohz_mode); 176 P_ns(last_tick); 177 P(tick_stopped); 178 P(idle_jiffies); 179 P(idle_calls); 180 P(idle_sleeps); 181 P_ns(idle_entrytime); 182 P_ns(idle_waketime); 183 P_ns(idle_exittime); 184 P_ns(idle_sleeptime); 185 P_ns(iowait_sleeptime); 186 P(last_jiffies); 187 P(next_jiffies); 188 P_ns(idle_expires); 189 SEQ_printf(m, "jiffies: %Lu\n", 190 (unsigned long long)jiffies); 191 } 192 #endif 193 194 #undef P 195 #undef P_ns 196 SEQ_printf(m, "\n"); 197 } 198 199 #ifdef CONFIG_GENERIC_CLOCKEVENTS 200 static void 201 print_tickdevice(struct seq_file *m, struct tick_device *td, int cpu) 202 { 203 struct clock_event_device *dev = td->evtdev; 204 205 SEQ_printf(m, "Tick Device: mode: %d\n", td->mode); 206 if (cpu < 0) 207 SEQ_printf(m, "Broadcast device\n"); 208 else 209 SEQ_printf(m, "Per CPU device: %d\n", cpu); 210 211 SEQ_printf(m, "Clock Event Device: "); 212 if (!dev) { 213 SEQ_printf(m, "<NULL>\n"); 214 return; 215 } 216 SEQ_printf(m, "%s\n", dev->name); 217 SEQ_printf(m, " max_delta_ns: %llu\n", 218 (unsigned long long) dev->max_delta_ns); 219 SEQ_printf(m, " min_delta_ns: %llu\n", 220 (unsigned long long) dev->min_delta_ns); 221 SEQ_printf(m, " mult: %u\n", dev->mult); 222 SEQ_printf(m, " shift: %u\n", dev->shift); 223 SEQ_printf(m, " mode: %d\n", dev->mode); 224 SEQ_printf(m, " next_event: %Ld nsecs\n", 225 (unsigned long long) ktime_to_ns(dev->next_event)); 226 227 SEQ_printf(m, " set_next_event: "); 228 print_name_offset(m, dev->set_next_event); 229 SEQ_printf(m, "\n"); 230 231 SEQ_printf(m, " set_mode: "); 232 print_name_offset(m, dev->set_mode); 233 SEQ_printf(m, "\n"); 234 235 SEQ_printf(m, " event_handler: "); 236 print_name_offset(m, dev->event_handler); 237 SEQ_printf(m, "\n"); 238 SEQ_printf(m, " retries: %lu\n", dev->retries); 239 SEQ_printf(m, "\n"); 240 } 241 242 static void timer_list_show_tickdevices_header(struct seq_file *m) 243 { 244 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST 245 print_tickdevice(m, tick_get_broadcast_device(), -1); 246 SEQ_printf(m, "tick_broadcast_mask: %08lx\n", 247 cpumask_bits(tick_get_broadcast_mask())[0]); 248 #ifdef CONFIG_TICK_ONESHOT 249 SEQ_printf(m, "tick_broadcast_oneshot_mask: %08lx\n", 250 cpumask_bits(tick_get_broadcast_oneshot_mask())[0]); 251 #endif 252 SEQ_printf(m, "\n"); 253 #endif 254 } 255 #endif 256 257 static inline void timer_list_header(struct seq_file *m, u64 now) 258 { 259 SEQ_printf(m, "Timer List Version: v0.7\n"); 260 SEQ_printf(m, "HRTIMER_MAX_CLOCK_BASES: %d\n", HRTIMER_MAX_CLOCK_BASES); 261 SEQ_printf(m, "now at %Ld nsecs\n", (unsigned long long)now); 262 SEQ_printf(m, "\n"); 263 } 264 265 static int timer_list_show(struct seq_file *m, void *v) 266 { 267 struct timer_list_iter *iter = v; 268 u64 now = ktime_to_ns(ktime_get()); 269 270 if (iter->cpu == -1 && !iter->second_pass) 271 timer_list_header(m, now); 272 else if (!iter->second_pass) 273 print_cpu(m, iter->cpu, iter->now); 274 #ifdef CONFIG_GENERIC_CLOCKEVENTS 275 else if (iter->cpu == -1 && iter->second_pass) 276 timer_list_show_tickdevices_header(m); 277 else 278 print_tickdevice(m, tick_get_device(iter->cpu), iter->cpu); 279 #endif 280 return 0; 281 } 282 283 void sysrq_timer_list_show(void) 284 { 285 u64 now = ktime_to_ns(ktime_get()); 286 int cpu; 287 288 timer_list_header(NULL, now); 289 290 for_each_online_cpu(cpu) 291 print_cpu(NULL, cpu, now); 292 293 #ifdef CONFIG_GENERIC_CLOCKEVENTS 294 timer_list_show_tickdevices_header(NULL); 295 for_each_online_cpu(cpu) 296 print_tickdevice(NULL, tick_get_device(cpu), cpu); 297 #endif 298 return; 299 } 300 301 static void *timer_list_start(struct seq_file *file, loff_t *offset) 302 { 303 struct timer_list_iter *iter = file->private; 304 305 if (!*offset) { 306 iter->cpu = -1; 307 iter->now = ktime_to_ns(ktime_get()); 308 } else if (iter->cpu >= nr_cpu_ids) { 309 #ifdef CONFIG_GENERIC_CLOCKEVENTS 310 if (!iter->second_pass) { 311 iter->cpu = -1; 312 iter->second_pass = true; 313 } else 314 return NULL; 315 #else 316 return NULL; 317 #endif 318 } 319 return iter; 320 } 321 322 static void *timer_list_next(struct seq_file *file, void *v, loff_t *offset) 323 { 324 struct timer_list_iter *iter = file->private; 325 iter->cpu = cpumask_next(iter->cpu, cpu_online_mask); 326 ++*offset; 327 return timer_list_start(file, offset); 328 } 329 330 static void timer_list_stop(struct seq_file *seq, void *v) 331 { 332 } 333 334 static const struct seq_operations timer_list_sops = { 335 .start = timer_list_start, 336 .next = timer_list_next, 337 .stop = timer_list_stop, 338 .show = timer_list_show, 339 }; 340 341 static int timer_list_open(struct inode *inode, struct file *filp) 342 { 343 return seq_open_private(filp, &timer_list_sops, 344 sizeof(struct timer_list_iter)); 345 } 346 347 static const struct file_operations timer_list_fops = { 348 .open = timer_list_open, 349 .read = seq_read, 350 .llseek = seq_lseek, 351 .release = seq_release_private, 352 }; 353 354 static int __init init_timer_list_procfs(void) 355 { 356 struct proc_dir_entry *pe; 357 358 pe = proc_create("timer_list", 0444, NULL, &timer_list_fops); 359 if (!pe) 360 return -ENOMEM; 361 return 0; 362 } 363 __initcall(init_timer_list_procfs); 364