From 289f480af87e45f7a6de6ba9b4c061c2e259fe98 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Fri, 16 Feb 2007 01:28:15 -0800 Subject: [PATCH] [PATCH] Add debugging feature /proc/timer_list add /proc/timer_list, which prints all currently pending (high-res) timers, all clock-event sources and their parameters in a human-readable form. Sample output: Timer List Version: v0.1 HRTIMER_MAX_CLOCK_BASES: 2 now at 4246046273872 nsecs cpu: 0 clock 0: .index: 0 .resolution: 1 nsecs .get_time: ktime_get_real .offset: 1273998312645738432 nsecs active timers: clock 1: .index: 1 .resolution: 1 nsecs .get_time: ktime_get .offset: 0 nsecs active timers: #0: , hrtimer_sched_tick, hrtimer_stop_sched_tick, swapper/0 # expires at 4246432689566 nsecs [in 386415694 nsecs] #1: , hrtimer_wakeup, do_nanosleep, pcscd/2050 # expires at 4247018194689 nsecs [in 971920817 nsecs] #2: , hrtimer_wakeup, do_nanosleep, irqbalance/1909 # expires at 4247351358392 nsecs [in 1305084520 nsecs] #3: , hrtimer_wakeup, do_nanosleep, crond/2157 # expires at 4249097614968 nsecs [in 3051341096 nsecs] #4: , it_real_fn, do_setitimer, syslogd/1888 # expires at 4251329900926 nsecs [in 5283627054 nsecs] .expires_next : 4246432689566 nsecs .hres_active : 1 .check_clocks : 0 .nr_events : 31306 .idle_tick : 4246020791890 nsecs .tick_stopped : 1 .idle_jiffies : 986504 .idle_calls : 40700 .idle_sleeps : 36014 .idle_entrytime : 4246019418883 nsecs .idle_sleeptime : 4178181972709 nsecs cpu: 1 clock 0: .index: 0 .resolution: 1 nsecs .get_time: ktime_get_real .offset: 1273998312645738432 nsecs active timers: clock 1: .index: 1 .resolution: 1 nsecs .get_time: ktime_get .offset: 0 nsecs active timers: #0: , hrtimer_sched_tick, hrtimer_restart_sched_tick, swapper/0 # expires at 4246050084568 nsecs [in 3810696 nsecs] #1: , hrtimer_wakeup, do_nanosleep, atd/2227 # expires at 4261010635003 nsecs [in 14964361131 nsecs] #2: , hrtimer_wakeup, do_nanosleep, smartd/2332 # expires at 5469485798970 nsecs [in 1223439525098 nsecs] .expires_next : 4246050084568 nsecs .hres_active : 1 .check_clocks : 0 .nr_events : 24043 .idle_tick : 4246046084568 nsecs .tick_stopped : 0 .idle_jiffies : 986510 .idle_calls : 26360 .idle_sleeps : 22551 .idle_entrytime : 4246043874339 nsecs .idle_sleeptime : 4170763761184 nsecs tick_broadcast_mask: 00000003 event_broadcast_mask: 00000001 CPU#0's local event device: Clock Event Device: lapic capabilities: 0000000e max_delta_ns: 807385544 min_delta_ns: 1443 mult: 44624025 shift: 32 set_next_event: lapic_next_event set_mode: lapic_timer_setup event_handler: hrtimer_interrupt .installed: 1 .expires: 4246432689566 nsecs CPU#1's local event device: Clock Event Device: lapic capabilities: 0000000e max_delta_ns: 807385544 min_delta_ns: 1443 mult: 44624025 shift: 32 set_next_event: lapic_next_event set_mode: lapic_timer_setup event_handler: hrtimer_interrupt .installed: 1 .expires: 4246050084568 nsecs Clock Event Device: hpet capabilities: 00000007 max_delta_ns: 2147483647 min_delta_ns: 3352 mult: 61496110 shift: 32 set_next_event: hpet_next_event set_mode: hpet_set_mode event_handler: handle_nextevt_broadcast Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner Cc: john stultz Cc: Roman Zippel Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/tick.h | 11 ++ kernel/time/Makefile | 2 +- kernel/time/tick-broadcast.c | 21 +++ kernel/time/tick-common.c | 8 + kernel/time/tick-sched.c | 5 + kernel/time/timer_list.c | 287 +++++++++++++++++++++++++++++++++++ 6 files changed, 333 insertions(+), 1 deletion(-) create mode 100644 kernel/time/timer_list.c diff --git a/include/linux/tick.h b/include/linux/tick.h index cf435e45959..9a7252e089b 100644 --- a/include/linux/tick.h +++ b/include/linux/tick.h @@ -59,6 +59,7 @@ struct tick_sched { extern void __init tick_init(void); extern int tick_is_oneshot_available(void); +extern struct tick_device *tick_get_device(int cpu); # ifdef CONFIG_HIGH_RES_TIMERS extern int tick_init_highres(void); @@ -69,6 +70,16 @@ extern void tick_cancel_sched_timer(int cpu); static inline void tick_cancel_sched_timer(int cpu) { } # endif /* HIGHRES */ +# ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST +extern struct tick_device *tick_get_broadcast_device(void); +extern cpumask_t *tick_get_broadcast_mask(void); + +# ifdef CONFIG_TICK_ONESHOT +extern cpumask_t *tick_get_broadcast_oneshot_mask(void); +# endif + +# endif /* BROADCAST */ + # ifdef CONFIG_TICK_ONESHOT extern void tick_clock_notify(void); extern int tick_check_oneshot_change(int allow_nohz); diff --git a/kernel/time/Makefile b/kernel/time/Makefile index 252b4b5d9dd..93bccba1f26 100644 --- a/kernel/time/Makefile +++ b/kernel/time/Makefile @@ -1,4 +1,4 @@ -obj-y += ntp.o clocksource.o jiffies.o +obj-y += ntp.o clocksource.o jiffies.o timer_list.o obj-$(CONFIG_GENERIC_CLOCKEVENTS) += clockevents.o obj-$(CONFIG_GENERIC_CLOCKEVENTS) += tick-common.o diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c index 8314ecb32d3..12b3efeb9f6 100644 --- a/kernel/time/tick-broadcast.c +++ b/kernel/time/tick-broadcast.c @@ -31,6 +31,19 @@ struct tick_device tick_broadcast_device; static cpumask_t tick_broadcast_mask; static DEFINE_SPINLOCK(tick_broadcast_lock); +/* + * Debugging: see timer_list.c + */ +struct tick_device *tick_get_broadcast_device(void) +{ + return &tick_broadcast_device; +} + +cpumask_t *tick_get_broadcast_mask(void) +{ + return &tick_broadcast_mask; +} + /* * Start the device in periodic mode */ @@ -275,6 +288,14 @@ void tick_shutdown_broadcast(unsigned int *cpup) static cpumask_t tick_broadcast_oneshot_mask; +/* + * Debugging: see timer_list.c + */ +cpumask_t *tick_get_broadcast_oneshot_mask(void) +{ + return &tick_broadcast_oneshot_mask; +} + static int tick_broadcast_set_event(ktime_t expires, int force) { struct clock_event_device *bc = tick_broadcast_device.evtdev; diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c index c35d449be03..4500e347f1b 100644 --- a/kernel/time/tick-common.c +++ b/kernel/time/tick-common.c @@ -34,6 +34,14 @@ ktime_t tick_period; static int tick_do_timer_cpu = -1; DEFINE_SPINLOCK(tick_device_lock); +/* + * Debugging: see timer_list.c + */ +struct tick_device *tick_get_device(int cpu) +{ + return &per_cpu(tick_cpu_device, cpu); +} + /** * tick_is_oneshot_available - check for a oneshot capable event device */ diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index 99d35e2af18..95e41f7f850 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -33,6 +33,11 @@ static DEFINE_PER_CPU(struct tick_sched, tick_cpu_sched); */ static ktime_t last_jiffies_update; +struct tick_sched *tick_get_tick_sched(int cpu) +{ + return &per_cpu(tick_cpu_sched, cpu); +} + /* * Must be called with interrupts disabled ! */ diff --git a/kernel/time/timer_list.c b/kernel/time/timer_list.c new file mode 100644 index 00000000000..f82c635c3d5 --- /dev/null +++ b/kernel/time/timer_list.c @@ -0,0 +1,287 @@ +/* + * kernel/time/timer_list.c + * + * List pending timers + * + * Copyright(C) 2006, Red Hat, Inc., Ingo Molnar + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include +#include +#include +#include +#include +#include +#include + +#include + +typedef void (*print_fn_t)(struct seq_file *m, unsigned int *classes); + +DECLARE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases); + +/* + * This allows printing both to /proc/timer_list and + * to the console (on SysRq-Q): + */ +#define SEQ_printf(m, x...) \ + do { \ + if (m) \ + seq_printf(m, x); \ + else \ + printk(x); \ + } while (0) + +static void print_name_offset(struct seq_file *m, void *sym) +{ + unsigned long addr = (unsigned long)sym; + char namebuf[KSYM_NAME_LEN+1]; + unsigned long size, offset; + const char *sym_name; + char *modname; + + sym_name = kallsyms_lookup(addr, &size, &offset, &modname, namebuf); + if (sym_name) + SEQ_printf(m, "%s", sym_name); + else + SEQ_printf(m, "<%p>", sym); +} + +static void +print_timer(struct seq_file *m, struct hrtimer *timer, int idx, u64 now) +{ +#ifdef CONFIG_TIMER_STATS + char tmp[TASK_COMM_LEN + 1]; +#endif + SEQ_printf(m, " #%d: ", idx); + print_name_offset(m, timer); + SEQ_printf(m, ", "); + print_name_offset(m, timer->function); + SEQ_printf(m, ", S:%02lx", timer->state); +#ifdef CONFIG_TIMER_STATS + SEQ_printf(m, ", "); + print_name_offset(m, timer->start_site); + memcpy(tmp, timer->start_comm, TASK_COMM_LEN); + tmp[TASK_COMM_LEN] = 0; + SEQ_printf(m, ", %s/%d", tmp, timer->start_pid); +#endif + SEQ_printf(m, "\n"); + SEQ_printf(m, " # expires at %Ld nsecs [in %Ld nsecs]\n", + (unsigned long long)ktime_to_ns(timer->expires), + (unsigned long long)(ktime_to_ns(timer->expires) - 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 rb_node *curr; + unsigned long flags; + +next_one: + i = 0; + spin_lock_irqsave(&base->cpu_base->lock, flags); + + curr = base->first; + /* + * 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 = rb_next(curr); + i++; + } + + if (curr) { + + timer = rb_entry(curr, struct hrtimer, node); + tmp = *timer; + spin_unlock_irqrestore(&base->cpu_base->lock, flags); + + print_timer(m, &tmp, i, now); + next++; + goto next_one; + } + 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, " .index: %d\n", + base->index); + SEQ_printf(m, " .resolution: %Ld nsecs\n", + (unsigned long long)ktime_to_ns(base->resolution)); + SEQ_printf(m, " .get_time: "); + print_name_offset(m, base->get_time); + SEQ_printf(m, "\n"); +#ifdef CONFIG_HIGH_RES_TIMERS + SEQ_printf(m, " .offset: %Ld nsecs\n", + ktime_to_ns(base->offset)); +#endif + SEQ_printf(m, "active timers:\n"); + print_active_timers(m, base, now); +} + +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, "\ncpu: %d\n", cpu); + for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) { + SEQ_printf(m, " clock %d:\n", i); + print_base(m, cpu_base->clock_base + i, now); + } +#define P(x) \ + SEQ_printf(m, " .%-15s: %Ld\n", #x, (u64)(cpu_base->x)) +#define P_ns(x) \ + SEQ_printf(m, " .%-15s: %Ld nsecs\n", #x, \ + (u64)(ktime_to_ns(cpu_base->x))) + +#ifdef CONFIG_HIGH_RES_TIMERS + P_ns(expires_next); + P(hres_active); + P(nr_events); +#endif +#undef P +#undef P_ns + +#ifdef CONFIG_TICK_ONESHOT +# define P(x) \ + SEQ_printf(m, " .%-15s: %Ld\n", #x, (u64)(ts->x)) +# define P_ns(x) \ + SEQ_printf(m, " .%-15s: %Ld nsecs\n", #x, \ + (u64)(ktime_to_ns(ts->x))) + { + struct tick_sched *ts = tick_get_tick_sched(cpu); + P(nohz_mode); + P_ns(idle_tick); + P(tick_stopped); + P(idle_jiffies); + P(idle_calls); + P(idle_sleeps); + P_ns(idle_entrytime); + P_ns(idle_sleeptime); + P(last_jiffies); + P(next_jiffies); + P_ns(idle_expires); + SEQ_printf(m, "jiffies: %Ld\n", (u64)jiffies); + } +#endif + +#undef P +#undef P_ns +} + +#ifdef CONFIG_GENERIC_CLOCKEVENTS +static void +print_tickdevice(struct seq_file *m, struct tick_device *td) +{ + struct clock_event_device *dev = td->evtdev; + + SEQ_printf(m, "\nTick Device: mode: %d\n", td->mode); + + SEQ_printf(m, "Clock Event Device: "); + if (!dev) { + SEQ_printf(m, "\n"); + return; + } + SEQ_printf(m, "%s\n", dev->name); + SEQ_printf(m, " max_delta_ns: %ld\n", dev->max_delta_ns); + SEQ_printf(m, " min_delta_ns: %ld\n", dev->min_delta_ns); + SEQ_printf(m, " mult: %ld\n", dev->mult); + SEQ_printf(m, " shift: %d\n", dev->shift); + SEQ_printf(m, " mode: %d\n", dev->mode); + SEQ_printf(m, " next_event: %Ld nsecs\n", + (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, "\n"); + + SEQ_printf(m, " set_mode: "); + print_name_offset(m, dev->set_mode); + SEQ_printf(m, "\n"); + + SEQ_printf(m, " event_handler: "); + print_name_offset(m, dev->event_handler); + SEQ_printf(m, "\n"); +} + +static void timer_list_show_tickdevices(struct seq_file *m) +{ + int cpu; + +#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST + print_tickdevice(m, tick_get_broadcast_device()); + SEQ_printf(m, "tick_broadcast_mask: %08lx\n", + tick_get_broadcast_mask()->bits[0]); +#ifdef CONFIG_TICK_ONESHOT + SEQ_printf(m, "tick_broadcast_oneshot_mask: %08lx\n", + tick_get_broadcast_oneshot_mask()->bits[0]); +#endif + SEQ_printf(m, "\n"); +#endif + for_each_online_cpu(cpu) + print_tickdevice(m, tick_get_device(cpu)); + SEQ_printf(m, "\n"); +} +#else +static void timer_list_show_tickdevices(struct seq_file *m) { } +#endif + +static int timer_list_show(struct seq_file *m, void *v) +{ + u64 now = ktime_to_ns(ktime_get()); + int cpu; + + SEQ_printf(m, "Timer List Version: v0.3\n"); + SEQ_printf(m, "HRTIMER_MAX_CLOCK_BASES: %d\n", HRTIMER_MAX_CLOCK_BASES); + SEQ_printf(m, "now at %Ld nsecs\n", (unsigned long long)now); + + for_each_online_cpu(cpu) + print_cpu(m, cpu, now); + + SEQ_printf(m, "\n"); + timer_list_show_tickdevices(m); + + return 0; +} + +void sysrq_timer_list_show(void) +{ + timer_list_show(NULL, NULL); +} + +static int timer_list_open(struct inode *inode, struct file *filp) +{ + return single_open(filp, timer_list_show, NULL); +} + +static struct file_operations timer_list_fops = { + .open = timer_list_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, +}; + +static int __init init_timer_list_procfs(void) +{ + struct proc_dir_entry *pe; + + pe = create_proc_entry("timer_list", 0644, NULL); + if (!pe) + return -ENOMEM; + + pe->proc_fops = &timer_list_fops; + + return 0; +} +__initcall(init_timer_list_procfs); -- 2.41.1