Many mfgpt timer interrupts with tickless kernel

[Chris Ball]

Hi Will,

   > I need to put a probe at a higher level to see what is run when the
   > timer fires. Is there something that can print out what is in the
   > clockevents_chain?

Not sure if you're aware that there are timer statistics available:

bash-3.1# echo 1 > /proc/timer_stats
bash-3.1# cat /proc/timer_stats
Timer Stats Version: v0.1
Sample period: 5.119 s
 512,     0 swapper          tick_nohz_restart_sched_tick (tick_sched_timer)
   1,  1511 python           schedule_timeout (process_timeout)
 401,  1462 python           schedule_timeout (process_timeout)
   1,  1395 X                do_setitimer (it_real_fn)
   1,     0 swapper          ehci_irq (ehci_watchdog)
 167,  1511 python           schedule_timeout (process_timeout)
  26,     4 events/0         fbcon_add_cursor_timer (cursor_timer_handler)
 107,  1395 X                do_setitimer (it_real_fn)
  26,  1228 dhcdbd           schedule_timeout (process_timeout)
  61,     0 swapper          ehci_irq (ehci_watchdog)
   1,  1201 modprobe         neigh_table_init_no_netlink (neigh_periodic_timer)
   8,  1414 wpa_supplicant   schedule_timeout (process_timeout)
   5,  1412 python           schedule_timeout (process_timeout)
   3,     1 swapper          neigh_table_init_no_netlink (neigh_periodic_timer)
   3,     1 swapper          queue_delayed_work_on (delayed_work_timer_fn)
   3,  1271 NetworkManager   schedule_timeout (process_timeout)
   1,     0 swapper          page_writeback_init (wb_timer_fn)
   1,  1414 wpa_supplicant   wlan_set_wap (delayed_work_timer_fn)
   5,  1201 modprobe         neigh_table_init_no_netlink (neigh_periodic_timer)
   1,     1 init             schedule_timeout (process_timeout)
   2,  1880 hald-addon-stor  do_nanosleep (hrtimer_wakeup)
   2,  1999 hald-addon-stor  do_nanosleep (hrtimer_wakeup)
  18,  1242 avahi-daemon     schedule_timeout (process_timeout)
   1,  1211 crond            do_nanosleep (hrtimer_wakeup)
   1,     0 swapper          neigh_update (neigh_timer_handler)
1358 total events, 271.265 events/sec
bash-3.1#

- Chris.
-- 
Chris Ball   <cjb at laptop.org>