/proc/timer_list 节点可以dump出当前系统中的hrtimer和tick device。
代码实现在 kernel/time/timer_list.c 中。
主要包括三部分信息：
1、 每个CPU的hrtimer base，每个base的clock base，每个clock base的timerqueue 2、 全局tick broadcast device 3、 每个CPU的tick device
其中，数据结构详情见hrtimer_bases全局变量。
Timer List Version: v0.9
HRTIMER_MAX_CLOCK_BASES: 8 # clock base for each hrtimer base
now at 47959154304 nsecs # boot time (CLOCK_MONOTONIC)
================= Per CPU hrtimer base / clock base / timerqueue =================
cpu: 0 # CPU
clock 0: # clock base 0
.base: 00000000bfe65cc8 # clock base variable address pointer
.index: 0 # internal enum index
.resolution: 1 nsecs # resolution
.get_time: ktime_get # clock get function
.offset: 0 nsecs
active timers: # timers in clock base 0
#0: <0000000006828050>, tick_sched_timer, S:01 # timer 0, handler, expires
# expires at 47964000000-47964000000 nsecs [in 4845696 to 4845696 nsecs]
#1: <00000000808cda1d>, sched_clock_poll, S:01 # timer 1, handler, expires
# expires at 4398054511096-4398054511096 nsecs [in 4350095356792 to 4350095356792 nsecs]
--------------- other clock base ---------------
clock 1:
.base: 00000000522d7a38
.index: 1
.resolution: 1 nsecs
.get_time: ktime_get_real
.offset: 1667996150000023072 nsecs
active timers:
clock 2:
.base: 0000000088d84c6c
.index: 2
.resolution: 1 nsecs
.get_time: ktime_get_boottime
.offset: 0 nsecs
active timers:
clock 3:
.base: 00000000ed610d9f
.index: 3
.resolution: 1 nsecs
.get_time: ktime_get_clocktai
.offset: 1667996150000023072 nsecs
active timers:
clock 4:
.base: 0000000049b42597
.index: 4
.resolution: 1 nsecs
.get_time: ktime_get
.offset: 0 nsecs
active timers:
clock 5:
.base: 00000000f2bc6e99
.index: 5
.resolution: 1 nsecs
.get_time: ktime_get_real
.offset: 1667996150000023072 nsecs
active timers:
clock 6:
.base: 000000002a6bd0e6
.index: 6
.resolution: 1 nsecs
.get_time: ktime_get_boottime
.offset: 0 nsecs
active timers:
clock 7:
.base: 000000005c04e6b8
.index: 7
.resolution: 1 nsecs
.get_time: ktime_get_clocktai
.offset: 1667996150000023072 nsecs
active timers:
.expires_next : 125916000000 nsecs
.hres_active : 1
.nr_events : 831
.nr_retries : 0
.nr_hangs : 0
.max_hang_time : 0
.nohz_mode : 2
.last_tick : 47964000000 nsecs
.tick_stopped : 1
.idle_jiffies : 4294904287
.idle_calls : 537
.idle_sleeps : 305
.idle_entrytime : 47960627648 nsecs
.idle_waketime : 47959759056 nsecs
.idle_exittime : 47959778576 nsecs
.idle_sleeptime : 45019336528 nsecs
.iowait_sleeptime: 0 nsecs
.last_jiffies : 4294904287
.next_timer : 125916000000
.idle_expires : 125916000000 nsecs
--------------- other clock base end ---------------
jiffies: 4294904287 # jiffies
<... Other CPU ...>
================= Tick Broadcast Device =================
Tick Device: mode: 1
Broadcast device
Clock Event Device: bc_hrtimer
max_delta_ns: 9223372036854775807
min_delta_ns: 1
mult: 1
shift: 0
mode: 1
next_event: 9223372036854775807 nsecs
set_next_event: 0x0
shutdown: bc_shutdown
event_handler: tick_handle_oneshot_broadcast
retries: 0
tick_broadcast_mask: 0
tick_broadcast_oneshot_mask: 0
================= Per CPU tick device =================
Tick Device: mode: 1 # is on
Per CPU device: 0 # cpu
Clock Event Device: arch_sys_timer # clock event device
max_delta_ns: 2199023255551
min_delta_ns: 1000
mult: 8388608
shift: 27
mode: 3
next_event: 125916000000 nsecs # next event time
set_next_event: arch_timer_set_next_event_virt
shutdown: arch_timer_shutdown_virt
oneshot stopped: arch_timer_shutdown_virt
event_handler: hrtimer_interrupt # tick device handler
retries: 0
Wakeup Device: <NULL>
<... Other CPU ...>