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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * List pending timers
4 *
5 * Copyright(C) 2006, Red Hat, Inc., Ingo Molnar
6 */
7
8#include <linux/proc_fs.h>
9#include <linux/module.h>
10#include <linux/spinlock.h>
11#include <linux/sched.h>
12#include <linux/seq_file.h>
13#include <linux/kallsyms.h>
14#include <linux/nmi.h>
15
16#include <linux/uaccess.h>
17
18#include "tick-internal.h"
19
20struct timer_list_iter {
21 int cpu;
22 bool second_pass;
23 u64 now;
24};
25
26/*
27 * This allows printing both to /proc/timer_list and
28 * to the console (on SysRq-Q):
29 */
30__printf(2, 3)
31static void SEQ_printf(struct seq_file *m, const char *fmt, ...)
32{
33 va_list args;
34
35 va_start(args, fmt);
36
37 if (m)
38 seq_vprintf(m, fmt, args);
39 else
40 vprintk(fmt, args);
41
42 va_end(args);
43}
44
45static void print_name_offset(struct seq_file *m, void *sym)
46{
47 char symname[KSYM_NAME_LEN];
48
49 if (lookup_symbol_name((unsigned long)sym, symname) < 0)
50 SEQ_printf(m, "<%pK>", sym);
51 else
52 SEQ_printf(m, "%s", symname);
53}
54
55static void
56print_timer(struct seq_file *m, struct hrtimer *taddr, struct hrtimer *timer,
57 int idx, u64 now)
58{
59 SEQ_printf(m, " #%d: ", idx);
60 print_name_offset(m, taddr);
61 SEQ_printf(m, ", ");
62 print_name_offset(m, timer->function);
63 SEQ_printf(m, ", S:%02x", timer->state);
64 SEQ_printf(m, "\n");
65 SEQ_printf(m, " # expires at %Lu-%Lu nsecs [in %Ld to %Ld nsecs]\n",
66 (unsigned long long)ktime_to_ns(hrtimer_get_softexpires(timer)),
67 (unsigned long long)ktime_to_ns(hrtimer_get_expires(timer)),
68 (long long)(ktime_to_ns(hrtimer_get_softexpires(timer)) - now),
69 (long long)(ktime_to_ns(hrtimer_get_expires(timer)) - now));
70}
71
72static void
73print_active_timers(struct seq_file *m, struct hrtimer_clock_base *base,
74 u64 now)
75{
76 struct hrtimer *timer, tmp;
77 unsigned long next = 0, i;
78 struct timerqueue_node *curr;
79 unsigned long flags;
80
81next_one:
82 i = 0;
83
84 touch_nmi_watchdog();
85
86 raw_spin_lock_irqsave(&base->cpu_base->lock, flags);
87
88 curr = timerqueue_getnext(&base->active);
89 /*
90 * Crude but we have to do this O(N*N) thing, because
91 * we have to unlock the base when printing:
92 */
93 while (curr && i < next) {
94 curr = timerqueue_iterate_next(curr);
95 i++;
96 }
97
98 if (curr) {
99
100 timer = container_of(curr, struct hrtimer, node);
101 tmp = *timer;
102 raw_spin_unlock_irqrestore(&base->cpu_base->lock, flags);
103
104 print_timer(m, timer, &tmp, i, now);
105 next++;
106 goto next_one;
107 }
108 raw_spin_unlock_irqrestore(&base->cpu_base->lock, flags);
109}
110
111static void
112print_base(struct seq_file *m, struct hrtimer_clock_base *base, u64 now)
113{
114 SEQ_printf(m, " .base: %pK\n", base);
115 SEQ_printf(m, " .index: %d\n", base->index);
116
117 SEQ_printf(m, " .resolution: %u nsecs\n", hrtimer_resolution);
118
119 SEQ_printf(m, " .get_time: ");
120 print_name_offset(m, base->get_time);
121 SEQ_printf(m, "\n");
122#ifdef CONFIG_HIGH_RES_TIMERS
123 SEQ_printf(m, " .offset: %Lu nsecs\n",
124 (unsigned long long) ktime_to_ns(base->offset));
125#endif
126 SEQ_printf(m, "active timers:\n");
127 print_active_timers(m, base, now + ktime_to_ns(base->offset));
128}
129
130static void print_cpu(struct seq_file *m, int cpu, u64 now)
131{
132 struct hrtimer_cpu_base *cpu_base = &per_cpu(hrtimer_bases, cpu);
133 int i;
134
135 SEQ_printf(m, "cpu: %d\n", cpu);
136 for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) {
137 SEQ_printf(m, " clock %d:\n", i);
138 print_base(m, cpu_base->clock_base + i, now);
139 }
140#define P(x) \
141 SEQ_printf(m, " .%-15s: %Lu\n", #x, \
142 (unsigned long long)(cpu_base->x))
143#define P_ns(x) \
144 SEQ_printf(m, " .%-15s: %Lu nsecs\n", #x, \
145 (unsigned long long)(ktime_to_ns(cpu_base->x)))
146
147#ifdef CONFIG_HIGH_RES_TIMERS
148 P_ns(expires_next);
149 P(hres_active);
150 P(nr_events);
151 P(nr_retries);
152 P(nr_hangs);
153 P(max_hang_time);
154#endif
155#undef P
156#undef P_ns
157
158#ifdef CONFIG_TICK_ONESHOT
159# define P(x) \
160 SEQ_printf(m, " .%-15s: %Lu\n", #x, \
161 (unsigned long long)(ts->x))
162# define P_ns(x) \
163 SEQ_printf(m, " .%-15s: %Lu nsecs\n", #x, \
164 (unsigned long long)(ktime_to_ns(ts->x)))
165 {
166 struct tick_sched *ts = tick_get_tick_sched(cpu);
167 P(nohz_mode);
168 P_ns(last_tick);
169 P(tick_stopped);
170 P(idle_jiffies);
171 P(idle_calls);
172 P(idle_sleeps);
173 P_ns(idle_entrytime);
174 P_ns(idle_waketime);
175 P_ns(idle_exittime);
176 P_ns(idle_sleeptime);
177 P_ns(iowait_sleeptime);
178 P(last_jiffies);
179 P(next_timer);
180 P_ns(idle_expires);
181 SEQ_printf(m, "jiffies: %Lu\n",
182 (unsigned long long)jiffies);
183 }
184#endif
185
186#undef P
187#undef P_ns
188 SEQ_printf(m, "\n");
189}
190
191#ifdef CONFIG_GENERIC_CLOCKEVENTS
192static void
193print_tickdevice(struct seq_file *m, struct tick_device *td, int cpu)
194{
195 struct clock_event_device *dev = td->evtdev;
196
197 touch_nmi_watchdog();
198
199 SEQ_printf(m, "Tick Device: mode: %d\n", td->mode);
200 if (cpu < 0)
201 SEQ_printf(m, "Broadcast device\n");
202 else
203 SEQ_printf(m, "Per CPU device: %d\n", cpu);
204
205 SEQ_printf(m, "Clock Event Device: ");
206 if (!dev) {
207 SEQ_printf(m, "<NULL>\n");
208 return;
209 }
210 SEQ_printf(m, "%s\n", dev->name);
211 SEQ_printf(m, " max_delta_ns: %llu\n",
212 (unsigned long long) dev->max_delta_ns);
213 SEQ_printf(m, " min_delta_ns: %llu\n",
214 (unsigned long long) dev->min_delta_ns);
215 SEQ_printf(m, " mult: %u\n", dev->mult);
216 SEQ_printf(m, " shift: %u\n", dev->shift);
217 SEQ_printf(m, " mode: %d\n", clockevent_get_state(dev));
218 SEQ_printf(m, " next_event: %Ld nsecs\n",
219 (unsigned long long) ktime_to_ns(dev->next_event));
220
221 SEQ_printf(m, " set_next_event: ");
222 print_name_offset(m, dev->set_next_event);
223 SEQ_printf(m, "\n");
224
225 if (dev->set_state_shutdown) {
226 SEQ_printf(m, " shutdown: ");
227 print_name_offset(m, dev->set_state_shutdown);
228 SEQ_printf(m, "\n");
229 }
230
231 if (dev->set_state_periodic) {
232 SEQ_printf(m, " periodic: ");
233 print_name_offset(m, dev->set_state_periodic);
234 SEQ_printf(m, "\n");
235 }
236
237 if (dev->set_state_oneshot) {
238 SEQ_printf(m, " oneshot: ");
239 print_name_offset(m, dev->set_state_oneshot);
240 SEQ_printf(m, "\n");
241 }
242
243 if (dev->set_state_oneshot_stopped) {
244 SEQ_printf(m, " oneshot stopped: ");
245 print_name_offset(m, dev->set_state_oneshot_stopped);
246 SEQ_printf(m, "\n");
247 }
248
249 if (dev->tick_resume) {
250 SEQ_printf(m, " resume: ");
251 print_name_offset(m, dev->tick_resume);
252 SEQ_printf(m, "\n");
253 }
254
255 SEQ_printf(m, " event_handler: ");
256 print_name_offset(m, dev->event_handler);
257 SEQ_printf(m, "\n");
258 SEQ_printf(m, " retries: %lu\n", dev->retries);
259 SEQ_printf(m, "\n");
260}
261
262static void timer_list_show_tickdevices_header(struct seq_file *m)
263{
264#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
265 print_tickdevice(m, tick_get_broadcast_device(), -1);
266 SEQ_printf(m, "tick_broadcast_mask: %*pb\n",
267 cpumask_pr_args(tick_get_broadcast_mask()));
268#ifdef CONFIG_TICK_ONESHOT
269 SEQ_printf(m, "tick_broadcast_oneshot_mask: %*pb\n",
270 cpumask_pr_args(tick_get_broadcast_oneshot_mask()));
271#endif
272 SEQ_printf(m, "\n");
273#endif
274}
275#endif
276
277static inline void timer_list_header(struct seq_file *m, u64 now)
278{
279 SEQ_printf(m, "Timer List Version: v0.8\n");
280 SEQ_printf(m, "HRTIMER_MAX_CLOCK_BASES: %d\n", HRTIMER_MAX_CLOCK_BASES);
281 SEQ_printf(m, "now at %Ld nsecs\n", (unsigned long long)now);
282 SEQ_printf(m, "\n");
283}
284
285void sysrq_timer_list_show(void)
286{
287 u64 now = ktime_to_ns(ktime_get());
288 int cpu;
289
290 timer_list_header(NULL, now);
291
292 for_each_online_cpu(cpu)
293 print_cpu(NULL, cpu, now);
294
295#ifdef CONFIG_GENERIC_CLOCKEVENTS
296 timer_list_show_tickdevices_header(NULL);
297 for_each_online_cpu(cpu)
298 print_tickdevice(NULL, tick_get_device(cpu), cpu);
299#endif
300 return;
301}
302
303#ifdef CONFIG_PROC_FS
304static int timer_list_show(struct seq_file *m, void *v)
305{
306 struct timer_list_iter *iter = v;
307
308 if (iter->cpu == -1 && !iter->second_pass)
309 timer_list_header(m, iter->now);
310 else if (!iter->second_pass)
311 print_cpu(m, iter->cpu, iter->now);
312#ifdef CONFIG_GENERIC_CLOCKEVENTS
313 else if (iter->cpu == -1 && iter->second_pass)
314 timer_list_show_tickdevices_header(m);
315 else
316 print_tickdevice(m, tick_get_device(iter->cpu), iter->cpu);
317#endif
318 return 0;
319}
320
321static void *move_iter(struct timer_list_iter *iter, loff_t offset)
322{
323 for (; offset; offset--) {
324 iter->cpu = cpumask_next(iter->cpu, cpu_online_mask);
325 if (iter->cpu >= nr_cpu_ids) {
326#ifdef CONFIG_GENERIC_CLOCKEVENTS
327 if (!iter->second_pass) {
328 iter->cpu = -1;
329 iter->second_pass = true;
330 } else
331 return NULL;
332#else
333 return NULL;
334#endif
335 }
336 }
337 return iter;
338}
339
340static void *timer_list_start(struct seq_file *file, loff_t *offset)
341{
342 struct timer_list_iter *iter = file->private;
343
344 if (!*offset)
345 iter->now = ktime_to_ns(ktime_get());
346 iter->cpu = -1;
347 iter->second_pass = false;
348 return move_iter(iter, *offset);
349}
350
351static void *timer_list_next(struct seq_file *file, void *v, loff_t *offset)
352{
353 struct timer_list_iter *iter = file->private;
354 ++*offset;
355 return move_iter(iter, 1);
356}
357
358static void timer_list_stop(struct seq_file *seq, void *v)
359{
360}
361
362static const struct seq_operations timer_list_sops = {
363 .start = timer_list_start,
364 .next = timer_list_next,
365 .stop = timer_list_stop,
366 .show = timer_list_show,
367};
368
369static int __init init_timer_list_procfs(void)
370{
371 struct proc_dir_entry *pe;
372
373 pe = proc_create_seq_private("timer_list", 0400, NULL, &timer_list_sops,
374 sizeof(struct timer_list_iter), NULL);
375 if (!pe)
376 return -ENOMEM;
377 return 0;
378}
379__initcall(init_timer_list_procfs);
380#endif
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
23typedef void (*print_fn_t)(struct seq_file *m, unsigned int *classes);
24
25DECLARE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases);
26
27/*
28 * This allows printing both to /proc/timer_list and
29 * to the console (on SysRq-Q):
30 */
31#define SEQ_printf(m, x...) \
32 do { \
33 if (m) \
34 seq_printf(m, x); \
35 else \
36 printk(x); \
37 } while (0)
38
39static void print_name_offset(struct seq_file *m, void *sym)
40{
41 char symname[KSYM_NAME_LEN];
42
43 if (lookup_symbol_name((unsigned long)sym, symname) < 0)
44 SEQ_printf(m, "<%pK>", sym);
45 else
46 SEQ_printf(m, "%s", symname);
47}
48
49static void
50print_timer(struct seq_file *m, struct hrtimer *taddr, struct hrtimer *timer,
51 int idx, u64 now)
52{
53#ifdef CONFIG_TIMER_STATS
54 char tmp[TASK_COMM_LEN + 1];
55#endif
56 SEQ_printf(m, " #%d: ", idx);
57 print_name_offset(m, taddr);
58 SEQ_printf(m, ", ");
59 print_name_offset(m, timer->function);
60 SEQ_printf(m, ", S:%02lx", timer->state);
61#ifdef CONFIG_TIMER_STATS
62 SEQ_printf(m, ", ");
63 print_name_offset(m, timer->start_site);
64 memcpy(tmp, timer->start_comm, TASK_COMM_LEN);
65 tmp[TASK_COMM_LEN] = 0;
66 SEQ_printf(m, ", %s/%d", tmp, timer->start_pid);
67#endif
68 SEQ_printf(m, "\n");
69 SEQ_printf(m, " # expires at %Lu-%Lu nsecs [in %Ld to %Ld nsecs]\n",
70 (unsigned long long)ktime_to_ns(hrtimer_get_softexpires(timer)),
71 (unsigned long long)ktime_to_ns(hrtimer_get_expires(timer)),
72 (long long)(ktime_to_ns(hrtimer_get_softexpires(timer)) - now),
73 (long long)(ktime_to_ns(hrtimer_get_expires(timer)) - now));
74}
75
76static void
77print_active_timers(struct seq_file *m, struct hrtimer_clock_base *base,
78 u64 now)
79{
80 struct hrtimer *timer, tmp;
81 unsigned long next = 0, i;
82 struct timerqueue_node *curr;
83 unsigned long flags;
84
85next_one:
86 i = 0;
87 raw_spin_lock_irqsave(&base->cpu_base->lock, flags);
88
89 curr = timerqueue_getnext(&base->active);
90 /*
91 * Crude but we have to do this O(N*N) thing, because
92 * we have to unlock the base when printing:
93 */
94 while (curr && i < next) {
95 curr = timerqueue_iterate_next(curr);
96 i++;
97 }
98
99 if (curr) {
100
101 timer = container_of(curr, struct hrtimer, node);
102 tmp = *timer;
103 raw_spin_unlock_irqrestore(&base->cpu_base->lock, flags);
104
105 print_timer(m, timer, &tmp, i, now);
106 next++;
107 goto next_one;
108 }
109 raw_spin_unlock_irqrestore(&base->cpu_base->lock, flags);
110}
111
112static void
113print_base(struct seq_file *m, struct hrtimer_clock_base *base, u64 now)
114{
115 SEQ_printf(m, " .base: %pK\n", base);
116 SEQ_printf(m, " .index: %d\n",
117 base->index);
118 SEQ_printf(m, " .resolution: %Lu nsecs\n",
119 (unsigned long long)ktime_to_ns(base->resolution));
120 SEQ_printf(m, " .get_time: ");
121 print_name_offset(m, base->get_time);
122 SEQ_printf(m, "\n");
123#ifdef CONFIG_HIGH_RES_TIMERS
124 SEQ_printf(m, " .offset: %Lu nsecs\n",
125 (unsigned long long) ktime_to_ns(base->offset));
126#endif
127 SEQ_printf(m, "active timers:\n");
128 print_active_timers(m, base, now);
129}
130
131static void print_cpu(struct seq_file *m, int cpu, u64 now)
132{
133 struct hrtimer_cpu_base *cpu_base = &per_cpu(hrtimer_bases, cpu);
134 int i;
135
136 SEQ_printf(m, "\n");
137 SEQ_printf(m, "cpu: %d\n", cpu);
138 for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) {
139 SEQ_printf(m, " clock %d:\n", i);
140 print_base(m, cpu_base->clock_base + i, now);
141 }
142#define P(x) \
143 SEQ_printf(m, " .%-15s: %Lu\n", #x, \
144 (unsigned long long)(cpu_base->x))
145#define P_ns(x) \
146 SEQ_printf(m, " .%-15s: %Lu nsecs\n", #x, \
147 (unsigned long long)(ktime_to_ns(cpu_base->x)))
148
149#ifdef CONFIG_HIGH_RES_TIMERS
150 P_ns(expires_next);
151 P(hres_active);
152 P(nr_events);
153 P(nr_retries);
154 P(nr_hangs);
155 P_ns(max_hang_time);
156#endif
157#undef P
158#undef P_ns
159
160#ifdef CONFIG_TICK_ONESHOT
161# define P(x) \
162 SEQ_printf(m, " .%-15s: %Lu\n", #x, \
163 (unsigned long long)(ts->x))
164# define P_ns(x) \
165 SEQ_printf(m, " .%-15s: %Lu nsecs\n", #x, \
166 (unsigned long long)(ktime_to_ns(ts->x)))
167 {
168 struct tick_sched *ts = tick_get_tick_sched(cpu);
169 P(nohz_mode);
170 P_ns(idle_tick);
171 P(tick_stopped);
172 P(idle_jiffies);
173 P(idle_calls);
174 P(idle_sleeps);
175 P_ns(idle_entrytime);
176 P_ns(idle_waketime);
177 P_ns(idle_exittime);
178 P_ns(idle_sleeptime);
179 P_ns(iowait_sleeptime);
180 P(last_jiffies);
181 P(next_jiffies);
182 P_ns(idle_expires);
183 SEQ_printf(m, "jiffies: %Lu\n",
184 (unsigned long long)jiffies);
185 }
186#endif
187
188#undef P
189#undef P_ns
190}
191
192#ifdef CONFIG_GENERIC_CLOCKEVENTS
193static void
194print_tickdevice(struct seq_file *m, struct tick_device *td, int cpu)
195{
196 struct clock_event_device *dev = td->evtdev;
197
198 SEQ_printf(m, "\n");
199 SEQ_printf(m, "Tick Device: mode: %d\n", td->mode);
200 if (cpu < 0)
201 SEQ_printf(m, "Broadcast device\n");
202 else
203 SEQ_printf(m, "Per CPU device: %d\n", cpu);
204
205 SEQ_printf(m, "Clock Event Device: ");
206 if (!dev) {
207 SEQ_printf(m, "<NULL>\n");
208 return;
209 }
210 SEQ_printf(m, "%s\n", dev->name);
211 SEQ_printf(m, " max_delta_ns: %llu\n",
212 (unsigned long long) dev->max_delta_ns);
213 SEQ_printf(m, " min_delta_ns: %llu\n",
214 (unsigned long long) dev->min_delta_ns);
215 SEQ_printf(m, " mult: %u\n", dev->mult);
216 SEQ_printf(m, " shift: %u\n", dev->shift);
217 SEQ_printf(m, " mode: %d\n", dev->mode);
218 SEQ_printf(m, " next_event: %Ld nsecs\n",
219 (unsigned long long) ktime_to_ns(dev->next_event));
220
221 SEQ_printf(m, " set_next_event: ");
222 print_name_offset(m, dev->set_next_event);
223 SEQ_printf(m, "\n");
224
225 SEQ_printf(m, " set_mode: ");
226 print_name_offset(m, dev->set_mode);
227 SEQ_printf(m, "\n");
228
229 SEQ_printf(m, " event_handler: ");
230 print_name_offset(m, dev->event_handler);
231 SEQ_printf(m, "\n");
232 SEQ_printf(m, " retries: %lu\n", dev->retries);
233}
234
235static void timer_list_show_tickdevices(struct seq_file *m)
236{
237 int cpu;
238
239#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
240 print_tickdevice(m, tick_get_broadcast_device(), -1);
241 SEQ_printf(m, "tick_broadcast_mask: %08lx\n",
242 cpumask_bits(tick_get_broadcast_mask())[0]);
243#ifdef CONFIG_TICK_ONESHOT
244 SEQ_printf(m, "tick_broadcast_oneshot_mask: %08lx\n",
245 cpumask_bits(tick_get_broadcast_oneshot_mask())[0]);
246#endif
247 SEQ_printf(m, "\n");
248#endif
249 for_each_online_cpu(cpu)
250 print_tickdevice(m, tick_get_device(cpu), cpu);
251 SEQ_printf(m, "\n");
252}
253#else
254static void timer_list_show_tickdevices(struct seq_file *m) { }
255#endif
256
257static int timer_list_show(struct seq_file *m, void *v)
258{
259 u64 now = ktime_to_ns(ktime_get());
260 int cpu;
261
262 SEQ_printf(m, "Timer List Version: v0.6\n");
263 SEQ_printf(m, "HRTIMER_MAX_CLOCK_BASES: %d\n", HRTIMER_MAX_CLOCK_BASES);
264 SEQ_printf(m, "now at %Ld nsecs\n", (unsigned long long)now);
265
266 for_each_online_cpu(cpu)
267 print_cpu(m, cpu, now);
268
269 SEQ_printf(m, "\n");
270 timer_list_show_tickdevices(m);
271
272 return 0;
273}
274
275void sysrq_timer_list_show(void)
276{
277 timer_list_show(NULL, NULL);
278}
279
280static int timer_list_open(struct inode *inode, struct file *filp)
281{
282 return single_open(filp, timer_list_show, NULL);
283}
284
285static const struct file_operations timer_list_fops = {
286 .open = timer_list_open,
287 .read = seq_read,
288 .llseek = seq_lseek,
289 .release = single_release,
290};
291
292static int __init init_timer_list_procfs(void)
293{
294 struct proc_dir_entry *pe;
295
296 pe = proc_create("timer_list", 0444, NULL, &timer_list_fops);
297 if (!pe)
298 return -ENOMEM;
299 return 0;
300}
301__initcall(init_timer_list_procfs);