// SPDX-License-Identifier: GPL-2.0

  /*

   * List pending timers
   *
   * Copyright(C) 2006, Red Hat, Inc., Ingo Molnar

   */
  
  #include <linux/proc_fs.h>
  #include <linux/module.h>
  #include <linux/spinlock.h>
  #include <linux/sched.h>
  #include <linux/seq_file.h>
  #include <linux/kallsyms.h>

  #include <linux/nmi.h>

  #include <linux/uaccess.h>

  #include "tick-internal.h"

  
  struct timer_list_iter {
  	int cpu;
  	bool second_pass;
  	u64 now;
  };

  /*
   * This allows printing both to /proc/timer_list and
   * to the console (on SysRq-Q):
   */

  __printf(2, 3)
  static void SEQ_printf(struct seq_file *m, const char *fmt, ...)
  {
  	va_list args;
  
  	va_start(args, fmt);
  
  	if (m)
  		seq_vprintf(m, fmt, args);
  	else
  		vprintk(fmt, args);
  
  	va_end(args);
  }

  
  static void print_name_offset(struct seq_file *m, void *sym)
  {

  	char symname[KSYM_NAME_LEN];

  	if (lookup_symbol_name((unsigned long)sym, symname) < 0)

  		SEQ_printf(m, "<%pK>", sym);

  	else
  		SEQ_printf(m, "%s", symname);

  }
  
  static void

  print_timer(struct seq_file *m, struct hrtimer *taddr, struct hrtimer *timer,
  	    int idx, u64 now)

  {

  	SEQ_printf(m, " #%d: ", idx);

  	print_name_offset(m, taddr);

  	SEQ_printf(m, ", ");
  	print_name_offset(m, timer->function);

  	SEQ_printf(m, ", S:%02x", timer->state);

  	SEQ_printf(m, "
  ");

  	SEQ_printf(m, " # expires at %Lu-%Lu nsecs [in %Ld to %Ld nsecs]
  ",
  		(unsigned long long)ktime_to_ns(hrtimer_get_softexpires(timer)),

  		(unsigned long long)ktime_to_ns(hrtimer_get_expires(timer)),

  		(long long)(ktime_to_ns(hrtimer_get_softexpires(timer)) - now),

  		(long long)(ktime_to_ns(hrtimer_get_expires(timer)) - now));

  }
  
  static void
  print_active_timers(struct seq_file *m, struct hrtimer_clock_base *base,
  		    u64 now)
  {
  	struct hrtimer *timer, tmp;
  	unsigned long next = 0, i;

  	struct timerqueue_node *curr;

  	unsigned long flags;
  
  next_one:
  	i = 0;

  
  	touch_nmi_watchdog();

  	raw_spin_lock_irqsave(&base->cpu_base->lock, flags);

  	curr = timerqueue_getnext(&base->active);

  	/*
  	 * Crude but we have to do this O(N*N) thing, because
  	 * we have to unlock the base when printing:
  	 */
  	while (curr && i < next) {

  		curr = timerqueue_iterate_next(curr);

  		i++;
  	}
  
  	if (curr) {

  		timer = container_of(curr, struct hrtimer, node);

  		tmp = *timer;

  		raw_spin_unlock_irqrestore(&base->cpu_base->lock, flags);

  		print_timer(m, timer, &tmp, i, now);

  		next++;
  		goto next_one;
  	}

  	raw_spin_unlock_irqrestore(&base->cpu_base->lock, flags);

  }
  
  static void
  print_base(struct seq_file *m, struct hrtimer_clock_base *base, u64 now)
  {

  	SEQ_printf(m, "  .base:       %pK
  ", base);

  	SEQ_printf(m, "  .index:      %d
  ", base->index);

  	SEQ_printf(m, "  .resolution: %u nsecs
  ", hrtimer_resolution);

  	SEQ_printf(m,   "  .get_time:   ");
  	print_name_offset(m, base->get_time);
  	SEQ_printf(m,   "
  ");
  #ifdef CONFIG_HIGH_RES_TIMERS

  	SEQ_printf(m, "  .offset:     %Lu nsecs
  ",
  		   (unsigned long long) ktime_to_ns(base->offset));

  #endif
  	SEQ_printf(m,   "active timers:
  ");

  	print_active_timers(m, base, now + ktime_to_ns(base->offset));

  }
  
  static void print_cpu(struct seq_file *m, int cpu, u64 now)
  {
  	struct hrtimer_cpu_base *cpu_base = &per_cpu(hrtimer_bases, cpu);
  	int i;

  	SEQ_printf(m, "cpu: %d
  ", cpu);

  	for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) {
  		SEQ_printf(m, " clock %d:
  ", i);
  		print_base(m, cpu_base->clock_base + i, now);
  	}
  #define P(x) \

  	SEQ_printf(m, "  .%-15s: %Lu
  ", #x, \
  		   (unsigned long long)(cpu_base->x))

  #define P_ns(x) \

  	SEQ_printf(m, "  .%-15s: %Lu nsecs
  ", #x, \
  		   (unsigned long long)(ktime_to_ns(cpu_base->x)))

  
  #ifdef CONFIG_HIGH_RES_TIMERS
  	P_ns(expires_next);
  	P(hres_active);
  	P(nr_events);

  	P(nr_retries);
  	P(nr_hangs);

  	P(max_hang_time);

  #endif
  #undef P
  #undef P_ns
  
  #ifdef CONFIG_TICK_ONESHOT
  # define P(x) \

  	SEQ_printf(m, "  .%-15s: %Lu
  ", #x, \
  		   (unsigned long long)(ts->x))

  # define P_ns(x) \

  	SEQ_printf(m, "  .%-15s: %Lu nsecs
  ", #x, \
  		   (unsigned long long)(ktime_to_ns(ts->x)))

  	{
  		struct tick_sched *ts = tick_get_tick_sched(cpu);
  		P(nohz_mode);

  		P_ns(last_tick);

  		P(tick_stopped);
  		P(idle_jiffies);
  		P(idle_calls);
  		P(idle_sleeps);
  		P_ns(idle_entrytime);

  		P_ns(idle_waketime);
  		P_ns(idle_exittime);

  		P_ns(idle_sleeptime);

  		P_ns(iowait_sleeptime);

  		P(last_jiffies);

  		P(next_timer);

  		P_ns(idle_expires);

  		SEQ_printf(m, "jiffies: %Lu
  ",
  			   (unsigned long long)jiffies);

  	}
  #endif
  
  #undef P
  #undef P_ns

  	SEQ_printf(m, "
  ");

  }
  
  #ifdef CONFIG_GENERIC_CLOCKEVENTS
  static void

  print_tickdevice(struct seq_file *m, struct tick_device *td, int cpu)

  {
  	struct clock_event_device *dev = td->evtdev;

  	touch_nmi_watchdog();

  	SEQ_printf(m, "Tick Device: mode:     %d
  ", td->mode);

  	if (cpu < 0)
  		SEQ_printf(m, "Broadcast device
  ");
  	else
  		SEQ_printf(m, "Per CPU device: %d
  ", cpu);

  
  	SEQ_printf(m, "Clock Event Device: ");
  	if (!dev) {
  		SEQ_printf(m, "<NULL>
  ");
  		return;
  	}
  	SEQ_printf(m, "%s
  ", dev->name);

  	SEQ_printf(m, " max_delta_ns:   %llu
  ",
  		   (unsigned long long) dev->max_delta_ns);
  	SEQ_printf(m, " min_delta_ns:   %llu
  ",
  		   (unsigned long long) dev->min_delta_ns);

  	SEQ_printf(m, " mult:           %u
  ", dev->mult);
  	SEQ_printf(m, " shift:          %u
  ", dev->shift);

  	SEQ_printf(m, " mode:           %d
  ", clockevent_get_state(dev));

  	SEQ_printf(m, " next_event:     %Ld nsecs
  ",
  		   (unsigned long long) ktime_to_ns(dev->next_event));
  
  	SEQ_printf(m, " set_next_event: ");
  	print_name_offset(m, dev->set_next_event);
  	SEQ_printf(m, "
  ");

  	if (dev->set_state_shutdown) {
  		SEQ_printf(m, " shutdown: ");
  		print_name_offset(m, dev->set_state_shutdown);
  		SEQ_printf(m, "
  ");
  	}
  
  	if (dev->set_state_periodic) {
  		SEQ_printf(m, " periodic: ");
  		print_name_offset(m, dev->set_state_periodic);
  		SEQ_printf(m, "
  ");
  	}
  
  	if (dev->set_state_oneshot) {
  		SEQ_printf(m, " oneshot:  ");
  		print_name_offset(m, dev->set_state_oneshot);
  		SEQ_printf(m, "
  ");
  	}
  
  	if (dev->set_state_oneshot_stopped) {
  		SEQ_printf(m, " oneshot stopped: ");
  		print_name_offset(m, dev->set_state_oneshot_stopped);
  		SEQ_printf(m, "
  ");
  	}
  
  	if (dev->tick_resume) {
  		SEQ_printf(m, " resume:   ");
  		print_name_offset(m, dev->tick_resume);

  		SEQ_printf(m, "
  ");

  	}

  
  	SEQ_printf(m, " event_handler:  ");
  	print_name_offset(m, dev->event_handler);
  	SEQ_printf(m, "
  ");

  	SEQ_printf(m, " retries:        %lu
  ", dev->retries);

  	SEQ_printf(m, "
  ");

  }

  static void timer_list_show_tickdevices_header(struct seq_file *m)

  {

  #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST

  	print_tickdevice(m, tick_get_broadcast_device(), -1);

  	SEQ_printf(m, "tick_broadcast_mask: %*pb
  ",
  		   cpumask_pr_args(tick_get_broadcast_mask()));

  #ifdef CONFIG_TICK_ONESHOT

  	SEQ_printf(m, "tick_broadcast_oneshot_mask: %*pb
  ",
  		   cpumask_pr_args(tick_get_broadcast_oneshot_mask()));

  #endif
  	SEQ_printf(m, "
  ");
  #endif

  }

  #endif

  static inline void timer_list_header(struct seq_file *m, u64 now)

  {

  	SEQ_printf(m, "Timer List Version: v0.8
  ");

  	SEQ_printf(m, "HRTIMER_MAX_CLOCK_BASES: %d
  ", HRTIMER_MAX_CLOCK_BASES);
  	SEQ_printf(m, "now at %Ld nsecs
  ", (unsigned long long)now);

  	SEQ_printf(m, "
  ");

  }

  void sysrq_timer_list_show(void)
  {
  	u64 now = ktime_to_ns(ktime_get());
  	int cpu;
  
  	timer_list_header(NULL, now);

  
  	for_each_online_cpu(cpu)

  		print_cpu(NULL, cpu, now);

  #ifdef CONFIG_GENERIC_CLOCKEVENTS

  	timer_list_show_tickdevices_header(NULL);

  	for_each_online_cpu(cpu)

  		print_tickdevice(NULL, tick_get_device(cpu), cpu);

  #endif

  	return;
  }

  #ifdef CONFIG_PROC_FS
  static int timer_list_show(struct seq_file *m, void *v)
  {
  	struct timer_list_iter *iter = v;
  
  	if (iter->cpu == -1 && !iter->second_pass)
  		timer_list_header(m, iter->now);
  	else if (!iter->second_pass)
  		print_cpu(m, iter->cpu, iter->now);
  #ifdef CONFIG_GENERIC_CLOCKEVENTS
  	else if (iter->cpu == -1 && iter->second_pass)
  		timer_list_show_tickdevices_header(m);
  	else
  		print_tickdevice(m, tick_get_device(iter->cpu), iter->cpu);
  #endif
  	return 0;
  }

  static void *move_iter(struct timer_list_iter *iter, loff_t offset)

  {

  	for (; offset; offset--) {
  		iter->cpu = cpumask_next(iter->cpu, cpu_online_mask);
  		if (iter->cpu >= nr_cpu_ids) {

  #ifdef CONFIG_GENERIC_CLOCKEVENTS

  			if (!iter->second_pass) {
  				iter->cpu = -1;
  				iter->second_pass = true;
  			} else
  				return NULL;

  #else

  			return NULL;

  #endif

  		}

  	}
  	return iter;

  }

  static void *timer_list_start(struct seq_file *file, loff_t *offset)
  {
  	struct timer_list_iter *iter = file->private;
  
  	if (!*offset)
  		iter->now = ktime_to_ns(ktime_get());
  	iter->cpu = -1;
  	iter->second_pass = false;
  	return move_iter(iter, *offset);
  }

  static void *timer_list_next(struct seq_file *file, void *v, loff_t *offset)

  {

  	struct timer_list_iter *iter = file->private;

  	++*offset;

  	return move_iter(iter, 1);

  }

  static void timer_list_stop(struct seq_file *seq, void *v)
  {
  }
  
  static const struct seq_operations timer_list_sops = {
  	.start = timer_list_start,
  	.next = timer_list_next,
  	.stop = timer_list_stop,
  	.show = timer_list_show,
  };

  static int __init init_timer_list_procfs(void)
  {
  	struct proc_dir_entry *pe;

  	pe = proc_create_seq_private("timer_list", 0400, NULL, &timer_list_sops,
  			sizeof(struct timer_list_iter), NULL);

  	if (!pe)
  		return -ENOMEM;

  	return 0;
  }
  __initcall(init_timer_list_procfs);

  #endif