WSL2-Linux-Kernel/kernel/time
Stephen Boyd a272dcca18 tick: broadcast: Check broadcast mode on CPU hotplug
On ARM systems the dummy clockevent is registered with the cpu
hotplug notifier chain before any other per-cpu clockevent. This
has the side-effect of causing the dummy clockevent to be
registered first in every hotplug sequence. Because the dummy is
first, we'll try to turn the broadcast source on but the code in
tick_device_uses_broadcast() assumes the broadcast source is in
periodic mode and calls tick_broadcast_start_periodic()
unconditionally.

On boot this isn't a problem because we typically haven't
switched into oneshot mode yet (if at all). During hotplug, if
the broadcast source isn't in periodic mode we'll replace the
broadcast oneshot handler with the broadcast periodic handler and
start emulating oneshot mode when we shouldn't. Due to the way
the broadcast oneshot handler programs the next_event it's
possible for it to contain KTIME_MAX and cause us to hang the
system when the periodic handler tries to program the next tick.
Fix this by using the appropriate function to start the broadcast
source.

Reported-by: Stephen Warren <swarren@nvidia.com>
Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Cc: Mark Rutland <Mark.Rutland@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: ARM kernel mailing list <linux-arm-kernel@lists.infradead.org>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Joseph Lo <josephl@nvidia.com>
Link: http://lkml.kernel.org/r/20130711140059.GA27430@codeaurora.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-07-12 12:35:40 +02:00
..
Kconfig Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-05-15 14:05:17 -07:00
Makefile sched_clock: Make ARM's sched_clock generic for all architectures 2013-06-12 14:02:13 -07:00
alarmtimer.c alarmtimer: Export symbols of functions declared in linux/alarmtimer.h 2013-06-12 14:02:12 -07:00
clockevents.c clockevents: Implement unbind functionality 2013-05-16 11:09:18 +02:00
clocksource.c clocksource: Reselect clocksource when watchdog validated high-res capability 2013-07-05 11:09:28 +02:00
jiffies.c time: Kill xtime_lock, replacing it with jiffies_lock 2012-11-13 14:08:23 -05:00
ntp.c ntp: Remove unused variable flags in __hardpps 2013-05-28 13:45:19 -07:00
ntp_internal.h ntp: Rework do_adjtimex to take timespec and tai arguments 2013-04-04 13:18:15 -07:00
posix-clock.c kernel: Fix files explicitly needing EXPORT_SYMBOL infrastructure 2011-10-31 19:30:05 -04:00
sched_clock.c ARM: sched_clock: Load cycle count after epoch stabilizes 2013-06-17 15:56:11 -07:00
tick-broadcast.c tick: broadcast: Check broadcast mode on CPU hotplug 2013-07-12 12:35:40 +02:00
tick-common.c tick: Sanitize broadcast control logic 2013-07-02 14:26:45 +02:00
tick-internal.h clockevents: Define CS_NAME_LEN unconditionally 2013-05-28 09:28:02 +02:00
tick-oneshot.c clockevents: Make minimum delay adjustments configurable 2011-09-08 11:10:56 +02:00
tick-sched.c Merge branch 'timers/core' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks into timers/urgent 2013-07-10 10:43:25 +02:00
timeconv.c time: add function to convert between calendar time and broken-down time for universal use 2009-09-24 07:20:56 -07:00
timekeeping.c Merge branch 'timers/posix-cpu-timers-for-tglx' of 2013-07-04 23:11:22 +02:00
timekeeping_debug.c power: Add option to log time spent in suspend 2013-05-29 12:57:34 -07:00
timekeeping_internal.h power: Add option to log time spent in suspend 2013-05-29 12:57:34 -07:00
timer_list.c timer_list: Convert timer list to be a proper seq_file 2013-04-17 20:51:02 +02:00
timer_stats.c locking, timer_stats: Annotate table_lock as raw 2011-09-13 11:12:00 +02:00