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+1];
42
43	if (lookup_symbol_name((unsigned long)sym, symname) < 0)
44		SEQ_printf(m, "<%p>", sym);
45	else
46		SEQ_printf(m, "%s", symname);
47}
48
49static void
50print_timer(struct seq_file *m, struct hrtimer *timer, int idx, u64 now)
51{
52#ifdef CONFIG_TIMER_STATS
53	char tmp[TASK_COMM_LEN + 1];
54#endif
55	SEQ_printf(m, " #%d: ", idx);
56	print_name_offset(m, timer);
57	SEQ_printf(m, ", ");
58	print_name_offset(m, timer->function);
59	SEQ_printf(m, ", S:%02lx", timer->state);
60#ifdef CONFIG_TIMER_STATS
61	SEQ_printf(m, ", ");
62	print_name_offset(m, timer->start_site);
63	memcpy(tmp, timer->start_comm, TASK_COMM_LEN);
64	tmp[TASK_COMM_LEN] = 0;
65	SEQ_printf(m, ", %s/%d", tmp, timer->start_pid);
66#endif
67	SEQ_printf(m, "\n");
68	SEQ_printf(m, " # expires at %Lu nsecs [in %Lu nsecs]\n",
69		(unsigned long long)ktime_to_ns(timer->expires),
70		(unsigned long long)(ktime_to_ns(timer->expires) - now));
71}
72
73static void
74print_active_timers(struct seq_file *m, struct hrtimer_clock_base *base,
75		    u64 now)
76{
77	struct hrtimer *timer, tmp;
78	unsigned long next = 0, i;
79	struct rb_node *curr;
80	unsigned long flags;
81
82next_one:
83	i = 0;
84	spin_lock_irqsave(&base->cpu_base->lock, flags);
85
86	curr = base->first;
87	/*
88	 * Crude but we have to do this O(N*N) thing, because
89	 * we have to unlock the base when printing:
90	 */
91	while (curr && i < next) {
92		curr = rb_next(curr);
93		i++;
94	}
95
96	if (curr) {
97
98		timer = rb_entry(curr, struct hrtimer, node);
99		tmp = *timer;
100		spin_unlock_irqrestore(&base->cpu_base->lock, flags);
101
102		print_timer(m, &tmp, i, now);
103		next++;
104		goto next_one;
105	}
106	spin_unlock_irqrestore(&base->cpu_base->lock, flags);
107}
108
109static void
110print_base(struct seq_file *m, struct hrtimer_clock_base *base, u64 now)
111{
112	SEQ_printf(m, "  .index:      %d\n",
113			base->index);
114	SEQ_printf(m, "  .resolution: %Lu nsecs\n",
115			(unsigned long long)ktime_to_ns(base->resolution));
116	SEQ_printf(m,   "  .get_time:   ");
117	print_name_offset(m, base->get_time);
118	SEQ_printf(m,   "\n");
119#ifdef CONFIG_HIGH_RES_TIMERS
120	SEQ_printf(m, "  .offset:     %Lu nsecs\n",
121		   (unsigned long long) ktime_to_ns(base->offset));
122#endif
123	SEQ_printf(m,   "active timers:\n");
124	print_active_timers(m, base, now);
125}
126
127static void print_cpu(struct seq_file *m, int cpu, u64 now)
128{
129	struct hrtimer_cpu_base *cpu_base = &per_cpu(hrtimer_bases, cpu);
130	int i;
131
132	SEQ_printf(m, "\ncpu: %d\n", cpu);
133	for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) {
134		SEQ_printf(m, " clock %d:\n", i);
135		print_base(m, cpu_base->clock_base + i, now);
136	}
137#define P(x) \
138	SEQ_printf(m, "  .%-15s: %Lu\n", #x, \
139		   (unsigned long long)(cpu_base->x))
140#define P_ns(x) \
141	SEQ_printf(m, "  .%-15s: %Lu nsecs\n", #x, \
142		   (unsigned long long)(ktime_to_ns(cpu_base->x)))
143
144#ifdef CONFIG_HIGH_RES_TIMERS
145	P_ns(expires_next);
146	P(hres_active);
147	P(nr_events);
148#endif
149#undef P
150#undef P_ns
151
152#ifdef CONFIG_TICK_ONESHOT
153# define P(x) \
154	SEQ_printf(m, "  .%-15s: %Lu\n", #x, \
155		   (unsigned long long)(ts->x))
156# define P_ns(x) \
157	SEQ_printf(m, "  .%-15s: %Lu nsecs\n", #x, \
158		   (unsigned long long)(ktime_to_ns(ts->x)))
159	{
160		struct tick_sched *ts = tick_get_tick_sched(cpu);
161		P(nohz_mode);
162		P_ns(idle_tick);
163		P(tick_stopped);
164		P(idle_jiffies);
165		P(idle_calls);
166		P(idle_sleeps);
167		P_ns(idle_entrytime);
168		P_ns(idle_sleeptime);
169		P(last_jiffies);
170		P(next_jiffies);
171		P_ns(idle_expires);
172		SEQ_printf(m, "jiffies: %Lu\n",
173			   (unsigned long long)jiffies);
174	}
175#endif
176
177#undef P
178#undef P_ns
179}
180
181#ifdef CONFIG_GENERIC_CLOCKEVENTS
182static void
183print_tickdevice(struct seq_file *m, struct tick_device *td)
184{
185	struct clock_event_device *dev = td->evtdev;
186
187	SEQ_printf(m, "\nTick Device: mode:     %d\n", td->mode);
188
189	SEQ_printf(m, "Clock Event Device: ");
190	if (!dev) {
191		SEQ_printf(m, "<NULL>\n");
192		return;
193	}
194	SEQ_printf(m, "%s\n", dev->name);
195	SEQ_printf(m, " max_delta_ns:   %lu\n", dev->max_delta_ns);
196	SEQ_printf(m, " min_delta_ns:   %lu\n", dev->min_delta_ns);
197	SEQ_printf(m, " mult:           %lu\n", dev->mult);
198	SEQ_printf(m, " shift:          %d\n", dev->shift);
199	SEQ_printf(m, " mode:           %d\n", dev->mode);
200	SEQ_printf(m, " next_event:     %Ld nsecs\n",
201		   (unsigned long long) ktime_to_ns(dev->next_event));
202
203	SEQ_printf(m, " set_next_event: ");
204	print_name_offset(m, dev->set_next_event);
205	SEQ_printf(m, "\n");
206
207	SEQ_printf(m, " set_mode:       ");
208	print_name_offset(m, dev->set_mode);
209	SEQ_printf(m, "\n");
210
211	SEQ_printf(m, " event_handler:  ");
212	print_name_offset(m, dev->event_handler);
213	SEQ_printf(m, "\n");
214}
215
216static void timer_list_show_tickdevices(struct seq_file *m)
217{
218	int cpu;
219
220#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
221	print_tickdevice(m, tick_get_broadcast_device());
222	SEQ_printf(m, "tick_broadcast_mask: %08lx\n",
223		   tick_get_broadcast_mask()->bits[0]);
224#ifdef CONFIG_TICK_ONESHOT
225	SEQ_printf(m, "tick_broadcast_oneshot_mask: %08lx\n",
226		   tick_get_broadcast_oneshot_mask()->bits[0]);
227#endif
228	SEQ_printf(m, "\n");
229#endif
230	for_each_online_cpu(cpu)
231		   print_tickdevice(m, tick_get_device(cpu));
232	SEQ_printf(m, "\n");
233}
234#else
235static void timer_list_show_tickdevices(struct seq_file *m) { }
236#endif
237
238static int timer_list_show(struct seq_file *m, void *v)
239{
240	u64 now = ktime_to_ns(ktime_get());
241	int cpu;
242
243	SEQ_printf(m, "Timer List Version: v0.3\n");
244	SEQ_printf(m, "HRTIMER_MAX_CLOCK_BASES: %d\n", HRTIMER_MAX_CLOCK_BASES);
245	SEQ_printf(m, "now at %Ld nsecs\n", (unsigned long long)now);
246
247	for_each_online_cpu(cpu)
248		print_cpu(m, cpu, now);
249
250	SEQ_printf(m, "\n");
251	timer_list_show_tickdevices(m);
252
253	return 0;
254}
255
256void sysrq_timer_list_show(void)
257{
258	timer_list_show(NULL, NULL);
259}
260
261static int timer_list_open(struct inode *inode, struct file *filp)
262{
263	return single_open(filp, timer_list_show, NULL);
264}
265
266static struct file_operations timer_list_fops = {
267	.open		= timer_list_open,
268	.read		= seq_read,
269	.llseek		= seq_lseek,
270	.release	= seq_release,
271};
272
273static int __init init_timer_list_procfs(void)
274{
275	struct proc_dir_entry *pe;
276
277	pe = create_proc_entry("timer_list", 0644, NULL);
278	if (!pe)
279		return -ENOMEM;
280
281	pe->proc_fops = &timer_list_fops;
282
283	return 0;
284}
285__initcall(init_timer_list_procfs);
286