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	 245a057fee
			
		
	
	
		245a057fee
		
	
	
	
	
		
			
			With the introduction of per-cpu wakeup devices that can be used in preference to the broadcast timer, print the name of such devices when they are available. Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20210524221818.15850-6-will@kernel.org
		
			
				
	
	
		
			360 lines
		
	
	
	
		
			8.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			360 lines
		
	
	
	
		
			8.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0
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| /*
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|  * List pending timers
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|  *
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|  * Copyright(C) 2006, Red Hat, Inc., Ingo Molnar
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|  */
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| 
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| #include <linux/proc_fs.h>
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| #include <linux/module.h>
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| #include <linux/spinlock.h>
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| #include <linux/sched.h>
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| #include <linux/seq_file.h>
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| #include <linux/kallsyms.h>
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| #include <linux/nmi.h>
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| 
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| #include <linux/uaccess.h>
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| 
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| #include "tick-internal.h"
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| 
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| struct timer_list_iter {
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| 	int cpu;
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| 	bool second_pass;
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| 	u64 now;
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| };
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| 
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| /*
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|  * This allows printing both to /proc/timer_list and
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|  * to the console (on SysRq-Q):
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|  */
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| __printf(2, 3)
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| static void SEQ_printf(struct seq_file *m, const char *fmt, ...)
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| {
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| 	va_list args;
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| 
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| 	va_start(args, fmt);
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| 
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| 	if (m)
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| 		seq_vprintf(m, fmt, args);
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| 	else
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| 		vprintk(fmt, args);
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| 
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| 	va_end(args);
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| }
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| 
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| static void
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| print_timer(struct seq_file *m, struct hrtimer *taddr, struct hrtimer *timer,
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| 	    int idx, u64 now)
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| {
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| 	SEQ_printf(m, " #%d: <%pK>, %ps", idx, taddr, timer->function);
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| 	SEQ_printf(m, ", S:%02x", timer->state);
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| 	SEQ_printf(m, "\n");
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| 	SEQ_printf(m, " # expires at %Lu-%Lu nsecs [in %Ld to %Ld nsecs]\n",
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| 		(unsigned long long)ktime_to_ns(hrtimer_get_softexpires(timer)),
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| 		(unsigned long long)ktime_to_ns(hrtimer_get_expires(timer)),
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| 		(long long)(ktime_to_ns(hrtimer_get_softexpires(timer)) - now),
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| 		(long long)(ktime_to_ns(hrtimer_get_expires(timer)) - now));
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| }
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| 
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| static void
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| print_active_timers(struct seq_file *m, struct hrtimer_clock_base *base,
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| 		    u64 now)
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| {
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| 	struct hrtimer *timer, tmp;
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| 	unsigned long next = 0, i;
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| 	struct timerqueue_node *curr;
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| 	unsigned long flags;
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| 
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| next_one:
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| 	i = 0;
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| 
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| 	touch_nmi_watchdog();
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| 
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| 	raw_spin_lock_irqsave(&base->cpu_base->lock, flags);
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| 
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| 	curr = timerqueue_getnext(&base->active);
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| 	/*
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| 	 * Crude but we have to do this O(N*N) thing, because
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| 	 * we have to unlock the base when printing:
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| 	 */
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| 	while (curr && i < next) {
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| 		curr = timerqueue_iterate_next(curr);
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| 		i++;
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| 	}
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| 
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| 	if (curr) {
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| 
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| 		timer = container_of(curr, struct hrtimer, node);
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| 		tmp = *timer;
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| 		raw_spin_unlock_irqrestore(&base->cpu_base->lock, flags);
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| 
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| 		print_timer(m, timer, &tmp, i, now);
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| 		next++;
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| 		goto next_one;
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| 	}
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| 	raw_spin_unlock_irqrestore(&base->cpu_base->lock, flags);
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| }
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| 
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| static void
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| print_base(struct seq_file *m, struct hrtimer_clock_base *base, u64 now)
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| {
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| 	SEQ_printf(m, "  .base:       %pK\n", base);
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| 	SEQ_printf(m, "  .index:      %d\n", base->index);
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| 
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| 	SEQ_printf(m, "  .resolution: %u nsecs\n", hrtimer_resolution);
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| 
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| 	SEQ_printf(m,   "  .get_time:   %ps\n", base->get_time);
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| #ifdef CONFIG_HIGH_RES_TIMERS
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| 	SEQ_printf(m, "  .offset:     %Lu nsecs\n",
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| 		   (unsigned long long) ktime_to_ns(base->offset));
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| #endif
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| 	SEQ_printf(m,   "active timers:\n");
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| 	print_active_timers(m, base, now + ktime_to_ns(base->offset));
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| }
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| 
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| static void print_cpu(struct seq_file *m, int cpu, u64 now)
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| {
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| 	struct hrtimer_cpu_base *cpu_base = &per_cpu(hrtimer_bases, cpu);
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| 	int i;
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| 
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| 	SEQ_printf(m, "cpu: %d\n", cpu);
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| 	for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) {
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| 		SEQ_printf(m, " clock %d:\n", i);
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| 		print_base(m, cpu_base->clock_base + i, now);
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| 	}
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| #define P(x) \
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| 	SEQ_printf(m, "  .%-15s: %Lu\n", #x, \
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| 		   (unsigned long long)(cpu_base->x))
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| #define P_ns(x) \
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| 	SEQ_printf(m, "  .%-15s: %Lu nsecs\n", #x, \
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| 		   (unsigned long long)(ktime_to_ns(cpu_base->x)))
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| 
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| #ifdef CONFIG_HIGH_RES_TIMERS
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| 	P_ns(expires_next);
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| 	P(hres_active);
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| 	P(nr_events);
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| 	P(nr_retries);
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| 	P(nr_hangs);
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| 	P(max_hang_time);
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| #endif
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| #undef P
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| #undef P_ns
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| 
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| #ifdef CONFIG_TICK_ONESHOT
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| # define P(x) \
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| 	SEQ_printf(m, "  .%-15s: %Lu\n", #x, \
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| 		   (unsigned long long)(ts->x))
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| # define P_ns(x) \
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| 	SEQ_printf(m, "  .%-15s: %Lu nsecs\n", #x, \
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| 		   (unsigned long long)(ktime_to_ns(ts->x)))
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| 	{
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| 		struct tick_sched *ts = tick_get_tick_sched(cpu);
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| 		P(nohz_mode);
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| 		P_ns(last_tick);
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| 		P(tick_stopped);
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| 		P(idle_jiffies);
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| 		P(idle_calls);
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| 		P(idle_sleeps);
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| 		P_ns(idle_entrytime);
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| 		P_ns(idle_waketime);
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| 		P_ns(idle_exittime);
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| 		P_ns(idle_sleeptime);
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| 		P_ns(iowait_sleeptime);
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| 		P(last_jiffies);
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| 		P(next_timer);
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| 		P_ns(idle_expires);
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| 		SEQ_printf(m, "jiffies: %Lu\n",
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| 			   (unsigned long long)jiffies);
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| 	}
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| #endif
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| 
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| #undef P
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| #undef P_ns
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| 	SEQ_printf(m, "\n");
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| }
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| 
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| #ifdef CONFIG_GENERIC_CLOCKEVENTS
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| static void
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| print_tickdevice(struct seq_file *m, struct tick_device *td, int cpu)
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| {
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| 	struct clock_event_device *dev = td->evtdev;
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| 
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| 	touch_nmi_watchdog();
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| 
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| 	SEQ_printf(m, "Tick Device: mode:     %d\n", td->mode);
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| 	if (cpu < 0)
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| 		SEQ_printf(m, "Broadcast device\n");
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| 	else
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| 		SEQ_printf(m, "Per CPU device: %d\n", cpu);
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| 
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| 	SEQ_printf(m, "Clock Event Device: ");
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| 	if (!dev) {
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| 		SEQ_printf(m, "<NULL>\n");
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| 		return;
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| 	}
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| 	SEQ_printf(m, "%s\n", dev->name);
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| 	SEQ_printf(m, " max_delta_ns:   %llu\n",
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| 		   (unsigned long long) dev->max_delta_ns);
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| 	SEQ_printf(m, " min_delta_ns:   %llu\n",
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| 		   (unsigned long long) dev->min_delta_ns);
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| 	SEQ_printf(m, " mult:           %u\n", dev->mult);
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| 	SEQ_printf(m, " shift:          %u\n", dev->shift);
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| 	SEQ_printf(m, " mode:           %d\n", clockevent_get_state(dev));
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| 	SEQ_printf(m, " next_event:     %Ld nsecs\n",
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| 		   (unsigned long long) ktime_to_ns(dev->next_event));
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| 
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| 	SEQ_printf(m, " set_next_event: %ps\n", dev->set_next_event);
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| 
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| 	if (dev->set_state_shutdown)
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| 		SEQ_printf(m, " shutdown:       %ps\n",
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| 			dev->set_state_shutdown);
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| 
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| 	if (dev->set_state_periodic)
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| 		SEQ_printf(m, " periodic:       %ps\n",
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| 			dev->set_state_periodic);
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| 
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| 	if (dev->set_state_oneshot)
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| 		SEQ_printf(m, " oneshot:        %ps\n",
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| 			dev->set_state_oneshot);
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| 
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| 	if (dev->set_state_oneshot_stopped)
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| 		SEQ_printf(m, " oneshot stopped: %ps\n",
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| 			dev->set_state_oneshot_stopped);
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| 
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| 	if (dev->tick_resume)
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| 		SEQ_printf(m, " resume:         %ps\n",
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| 			dev->tick_resume);
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| 
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| 	SEQ_printf(m, " event_handler:  %ps\n", dev->event_handler);
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| 	SEQ_printf(m, "\n");
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| 	SEQ_printf(m, " retries:        %lu\n", dev->retries);
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| 
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| #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
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| 	if (cpu >= 0) {
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| 		const struct clock_event_device *wd = tick_get_wakeup_device(cpu);
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| 
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| 		SEQ_printf(m, "Wakeup Device: %s\n", wd ? wd->name : "<NULL>");
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| 	}
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| #endif
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| 	SEQ_printf(m, "\n");
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| }
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| 
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| static void timer_list_show_tickdevices_header(struct seq_file *m)
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| {
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| #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
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| 	print_tickdevice(m, tick_get_broadcast_device(), -1);
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| 	SEQ_printf(m, "tick_broadcast_mask: %*pb\n",
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| 		   cpumask_pr_args(tick_get_broadcast_mask()));
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| #ifdef CONFIG_TICK_ONESHOT
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| 	SEQ_printf(m, "tick_broadcast_oneshot_mask: %*pb\n",
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| 		   cpumask_pr_args(tick_get_broadcast_oneshot_mask()));
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| #endif
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| 	SEQ_printf(m, "\n");
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| #endif
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| }
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| #endif
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| 
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| static inline void timer_list_header(struct seq_file *m, u64 now)
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| {
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| 	SEQ_printf(m, "Timer List Version: v0.9\n");
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| 	SEQ_printf(m, "HRTIMER_MAX_CLOCK_BASES: %d\n", HRTIMER_MAX_CLOCK_BASES);
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| 	SEQ_printf(m, "now at %Ld nsecs\n", (unsigned long long)now);
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| 	SEQ_printf(m, "\n");
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| }
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| 
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| void sysrq_timer_list_show(void)
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| {
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| 	u64 now = ktime_to_ns(ktime_get());
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| 	int cpu;
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| 
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| 	timer_list_header(NULL, now);
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| 
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| 	for_each_online_cpu(cpu)
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| 		print_cpu(NULL, cpu, now);
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| 
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| #ifdef CONFIG_GENERIC_CLOCKEVENTS
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| 	timer_list_show_tickdevices_header(NULL);
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| 	for_each_online_cpu(cpu)
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| 		print_tickdevice(NULL, tick_get_device(cpu), cpu);
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| #endif
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| 	return;
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| }
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| 
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| #ifdef CONFIG_PROC_FS
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| static int timer_list_show(struct seq_file *m, void *v)
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| {
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| 	struct timer_list_iter *iter = v;
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| 
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| 	if (iter->cpu == -1 && !iter->second_pass)
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| 		timer_list_header(m, iter->now);
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| 	else if (!iter->second_pass)
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| 		print_cpu(m, iter->cpu, iter->now);
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| #ifdef CONFIG_GENERIC_CLOCKEVENTS
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| 	else if (iter->cpu == -1 && iter->second_pass)
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| 		timer_list_show_tickdevices_header(m);
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| 	else
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| 		print_tickdevice(m, tick_get_device(iter->cpu), iter->cpu);
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| #endif
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| 	return 0;
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| }
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| 
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| static void *move_iter(struct timer_list_iter *iter, loff_t offset)
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| {
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| 	for (; offset; offset--) {
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| 		iter->cpu = cpumask_next(iter->cpu, cpu_online_mask);
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| 		if (iter->cpu >= nr_cpu_ids) {
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| #ifdef CONFIG_GENERIC_CLOCKEVENTS
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| 			if (!iter->second_pass) {
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| 				iter->cpu = -1;
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| 				iter->second_pass = true;
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| 			} else
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| 				return NULL;
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| #else
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| 			return NULL;
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| #endif
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| 		}
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| 	}
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| 	return iter;
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| }
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| 
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| static void *timer_list_start(struct seq_file *file, loff_t *offset)
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| {
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| 	struct timer_list_iter *iter = file->private;
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| 
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| 	if (!*offset)
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| 		iter->now = ktime_to_ns(ktime_get());
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| 	iter->cpu = -1;
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| 	iter->second_pass = false;
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| 	return move_iter(iter, *offset);
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| }
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| 
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| static void *timer_list_next(struct seq_file *file, void *v, loff_t *offset)
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| {
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| 	struct timer_list_iter *iter = file->private;
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| 	++*offset;
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| 	return move_iter(iter, 1);
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| }
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| 
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| static void timer_list_stop(struct seq_file *seq, void *v)
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| {
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| }
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| 
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| static const struct seq_operations timer_list_sops = {
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| 	.start = timer_list_start,
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| 	.next = timer_list_next,
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| 	.stop = timer_list_stop,
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| 	.show = timer_list_show,
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| };
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| 
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| static int __init init_timer_list_procfs(void)
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| {
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| 	struct proc_dir_entry *pe;
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| 
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| 	pe = proc_create_seq_private("timer_list", 0400, NULL, &timer_list_sops,
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| 			sizeof(struct timer_list_iter), NULL);
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| 	if (!pe)
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| 		return -ENOMEM;
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| 	return 0;
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| }
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| __initcall(init_timer_list_procfs);
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| #endif
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