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 typedef void (*print_fn_t)(struct seq_file *m, unsigned int *classes);
24
25 DECLARE_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
print_name_offset(struct seq_file * m,void * sym)39 static 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
49 static void
print_timer(struct seq_file * m,struct hrtimer * taddr,struct hrtimer * timer,int idx,u64 now)50 print_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
76 static void
print_active_timers(struct seq_file * m,struct hrtimer_clock_base * base,u64 now)77 print_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
85 next_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
112 static void
print_base(struct seq_file * m,struct hrtimer_clock_base * base,u64 now)113 print_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
print_cpu(struct seq_file * m,int cpu,u64 now)131 static 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
193 static void
print_tickdevice(struct seq_file * m,struct tick_device * td,int cpu)194 print_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
timer_list_show_tickdevices(struct seq_file * m)235 static 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
timer_list_show_tickdevices(struct seq_file * m)254 static void timer_list_show_tickdevices(struct seq_file *m) { }
255 #endif
256
timer_list_show(struct seq_file * m,void * v)257 static 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
sysrq_timer_list_show(void)275 void sysrq_timer_list_show(void)
276 {
277 timer_list_show(NULL, NULL);
278 }
279
timer_list_open(struct inode * inode,struct file * filp)280 static int timer_list_open(struct inode *inode, struct file *filp)
281 {
282 return single_open(filp, timer_list_show, NULL);
283 }
284
285 static 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
init_timer_list_procfs(void)292 static 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);
302