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