linux/kernel/time
john stultz 74a03b69d1 clockevents: prevent endless loop in tick_handle_periodic()
tick_handle_periodic() can lock up hard when a one shot clock event
device is used in combination with jiffies clocksource.

Avoid an endless loop issue by requiring that a highres valid
clocksource be installed before we call tick_periodic() in a loop when
using ONESHOT mode. The result is we will only increment jiffies once
per interrupt until a continuous hardware clocksource is available.

Without this, we can run into a endless loop, where each cycle through
the loop, jiffies is updated which increments time by tick_period or
more (due to clock steering), which can cause the event programming to
think the next event was before the newly incremented time and fail
causing tick_periodic() to be called again and the whole process loops
forever.

[ Impact: prevent hard lock up ]

Signed-off-by: John Stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@kernel.org
2009-05-02 10:22:27 +02:00
..
clockevents.c clockevents: let set_mode() setup delta information 2009-01-16 12:27:39 +01:00
clocksource.c clocksource: pass clocksource to read() callback 2009-04-21 13:41:47 -07:00
jiffies.c clocksource: pass clocksource to read() callback 2009-04-21 13:41:47 -07:00
Kconfig Kconfig: eliminate "def_bool n" constructs 2008-10-16 11:21:31 -07:00
Makefile timecompare: generic infrastructure to map between two time bases 2009-02-15 22:43:32 -08:00
ntp.c time: ntp: fix bug in ntp_update_offset() & do_adjtimex(), fix 2009-02-26 19:39:47 +01:00
tick-broadcast.c cpumask: replace for_each_cpu_mask_nr with for_each_cpu in kernel/time/ 2009-01-01 10:12:29 +10:30
tick-common.c clockevents: prevent endless loop in tick_handle_periodic() 2009-05-02 10:22:27 +02:00
tick-internal.h NOHZ: restart tick device from irq_enter() 2008-10-17 18:13:38 +02:00
tick-oneshot.c clockevents: remove WARN_ON which was used to gather information 2008-09-09 22:20:01 +02:00
tick-sched.c time-sched.c: tick_nohz_update_jiffies should be static 2009-01-15 12:06:56 +01:00
timecompare.c timecompare: generic infrastructure to map between two time bases 2009-02-15 22:43:32 -08:00
timekeeping.c clocksource: add enable() and disable() callbacks 2009-04-21 13:41:47 -07:00
timer_list.c Merge branch 'timers/range-hrtimers' into v28-range-hrtimers-for-linus-v2 2008-10-22 09:48:06 +02:00
timer_stats.c