linux/kernel/time
Frederic Weisbecker 2bbb6817c0 nohz: Allow rcu extended quiescent state handling seperately from tick stop
It is assumed that rcu won't be used once we switch to tickless
mode and until we restart the tick. However this is not always
true, as in x86-64 where we dereference the idle notifiers after
the tick is stopped.

To prepare for fixing this, add two new APIs:
tick_nohz_idle_enter_norcu() and tick_nohz_idle_exit_norcu().

If no use of RCU is made in the idle loop between
tick_nohz_enter_idle() and tick_nohz_exit_idle() calls, the arch
must instead call the new *_norcu() version such that the arch doesn't
need to call rcu_idle_enter() and rcu_idle_exit().

Otherwise the arch must call tick_nohz_enter_idle() and
tick_nohz_exit_idle() and also call explicitly:

- rcu_idle_enter() after its last use of RCU before the CPU is put
to sleep.
- rcu_idle_exit() before the first use of RCU after the CPU is woken
up.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: David Miller <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-12-11 10:31:36 -08:00
..
alarmtimer.c alarmtimers: Fix time comparison 2011-12-06 11:38:32 +01:00
clockevents.c clockevents: Set noop handler in clockevents_exchange_device() 2011-12-02 16:07:23 +01:00
clocksource.c clocksource: Fix bug with max_deferment margin calculation 2011-12-01 15:50:00 -08:00
jiffies.c Fix common misspellings 2011-03-31 11:26:23 -03:00
Kconfig clockevents: Make minimum delay adjustments configurable 2011-09-08 11:10:56 +02:00
Makefile timers: Introduce in-kernel alarm-timer interface 2011-04-26 14:01:44 -07:00
ntp.c ntp: fix non privileged system time shifting 2011-04-04 08:31:23 -07:00
posix-clock.c kernel: Fix files explicitly needing EXPORT_SYMBOL infrastructure 2011-10-31 19:30:05 -04:00
tick-broadcast.c tick-broadcast: Stop active broadcast device when replacing it 2011-12-02 16:06:54 +01:00
tick-common.c clockevents: Make minimum delay adjustments configurable 2011-09-08 11:10:56 +02:00
tick-internal.h clockevents: Make minimum delay adjustments configurable 2011-09-08 11:10:56 +02:00
tick-oneshot.c clockevents: Make minimum delay adjustments configurable 2011-09-08 11:10:56 +02:00
tick-sched.c nohz: Allow rcu extended quiescent state handling seperately from tick stop 2011-12-11 10:31:36 -08:00
timecompare.c
timeconv.c
timekeeping.c timekeeping: add arch_offset hook to ktime_get functions 2011-11-17 14:57:19 -08:00
timer_list.c timer debug: Hide kernel addresses via %pK in /proc/timer_list 2011-02-12 14:11:56 +01:00
timer_stats.c locking, timer_stats: Annotate table_lock as raw 2011-09-13 11:12:00 +02:00