Frederic Weisbecker 280f06774a nohz: Separate out irq exit and idle loop dyntick logic ... The tick_nohz_stop_sched_tick() function, which tries to delay the next timer tick as long as possible, can be called from two places: - From the idle loop to start the dytick idle mode - From interrupt exit if we have interrupted the dyntick idle mode, so that we reprogram the next tick event in case the irq changed some internal state that requires this action. There are only few minor differences between both that are handled by that function, driven by the ts->inidle cpu variable and the inidle parameter. The whole guarantees that we only update the dyntick mode on irq exit if we actually interrupted the dyntick idle mode, and that we enter in RCU extended quiescent state from idle loop entry only. Split this function into: - tick_nohz_idle_enter(), which sets ts->inidle to 1, enters dynticks idle mode unconditionally if it can, and enters into RCU extended quiescent state. - tick_nohz_irq_exit() which only updates the dynticks idle mode when ts->inidle is set (ie: if tick_nohz_idle_enter() has been called). To maintain symmetry, tick_nohz_restart_sched_tick() has been renamed into tick_nohz_idle_exit(). This simplifies the code and micro-optimize the irq exit path (no need for local_irq_save there). This also prepares for the split between dynticks and rcu extended quiescent state logics. We'll need this split to further fix illegal uses of RCU in extended quiescent states in the idle loop. 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> Reviewed-by: Josh Triplett <josh@joshtriplett.org>		2011-12-11 10:31:35 -08:00
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alpha
arm	nohz: Separate out irq exit and idle loop dyntick logic	2011-12-11 10:31:35 -08:00
avr32	nohz: Separate out irq exit and idle loop dyntick logic	2011-12-11 10:31:35 -08:00
blackfin	nohz: Separate out irq exit and idle loop dyntick logic	2011-12-11 10:31:35 -08:00
cris
frv
h8300
hexagon
ia64
m32r
m68k	m68k: Wire up process_vm_{read,write}v	2011-12-06 20:37:58 +01:00
microblaze	nohz: Separate out irq exit and idle loop dyntick logic	2011-12-11 10:31:35 -08:00
mips	nohz: Separate out irq exit and idle loop dyntick logic	2011-12-11 10:31:35 -08:00
mn10300
openrisc	nohz: Separate out irq exit and idle loop dyntick logic	2011-12-11 10:31:35 -08:00
parisc
powerpc	nohz: Separate out irq exit and idle loop dyntick logic	2011-12-11 10:31:35 -08:00
s390	nohz: Separate out irq exit and idle loop dyntick logic	2011-12-11 10:31:35 -08:00
score
sh	nohz: Separate out irq exit and idle loop dyntick logic	2011-12-11 10:31:35 -08:00
sparc	nohz: Separate out irq exit and idle loop dyntick logic	2011-12-11 10:31:35 -08:00
tile	nohz: Separate out irq exit and idle loop dyntick logic	2011-12-11 10:31:35 -08:00
um	nohz: Separate out irq exit and idle loop dyntick logic	2011-12-11 10:31:35 -08:00
unicore32	nohz: Separate out irq exit and idle loop dyntick logic	2011-12-11 10:31:35 -08:00
x86	nohz: Separate out irq exit and idle loop dyntick logic	2011-12-11 10:31:35 -08:00
xtensa
.gitignore
Kconfig