linux/arch/sh
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
..
boards Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media 2011-11-04 07:58:25 -07:00
boot sh: kexec: Add PHYSICAL_START 2011-10-28 15:03:43 +09:00
cchips sh: Convert to new function names 2011-03-29 14:48:13 +02:00
configs sh: fix compile error using sh7757lcr_defconfig 2011-06-21 17:40:42 +09:00
drivers Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
include sh: Wire up process_vm syscalls. 2011-11-11 10:58:16 +09:00
kernel nohz: Allow rcu extended quiescent state handling seperately from tick stop 2011-12-11 10:31:36 -08:00
lib sh: Ensure ST40-300 BogoMIPS value is consistent 2011-02-15 16:24:05 +09:00
lib64 Fix common misspellings 2011-03-31 11:26:23 -03:00
math-emu perf: Remove the nmi parameter from the swevent and overflow interface 2011-07-01 11:06:35 +02:00
mm Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
oprofile sh: remove warning and warning_symbol from struct stacktrace_ops 2011-05-23 14:42:15 +09:00
tools sh: Add support for AP-SH4AD-0A board. 2011-01-13 18:36:21 +09:00
Kconfig sh: kexec: Add PHYSICAL_START 2011-10-28 15:03:43 +09:00
Kconfig.cpu sh: Turn on speculative return for SH7785 and SH7786 2010-02-18 18:54:18 +09:00
Kconfig.debug lib: consolidate DEBUG_STACK_USAGE option 2011-05-25 08:39:54 -07:00
Makefile sh: Add default uImage rule for sh7757lcr 2011-11-01 16:01:12 +09:00