linux-toradex.git/arch/sh/kernel/idle.c, branch v4.2.7

sched/idle, SH: Remove redundant cpuidle_idle_call()

2014-02-11T08:58:26+00:00

The core idle loop now takes care of it.

Signed-off-by: Nicolas Pitre 
Acked-by: Daniel Lezcano 
Cc: Preeti U Murthy 
Cc: Paul Mundt 
Cc: "Rafael J. Wysocki" 
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-sh@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Cc: Russell King 
Cc: linaro-kernel@lists.linaro.org
Cc: Benjamin Herrenschmidt 
Signed-off-by: Peter Zijlstra 
Link: http://lkml.kernel.org/n/tip-v2c3oswyd80xk2vh7fwmu6r8@git.kernel.org
Signed-off-by: Ingo Molnar

sh: Use generic idle loop

2013-04-08T15:39:28+00:00

Signed-off-by: Thomas Gleixner 
Cc: Linus Torvalds 
Cc: Rusty Russell 
Cc: Paul McKenney 
Cc: Peter Zijlstra 
Reviewed-by: Cc: Srivatsa S. Bhat 
Cc: Magnus Damm 
Cc: Paul Mundt 
Link: http://lkml.kernel.org/r/20130321215235.216323644@linutronix.de
Signed-off-by: Thomas Gleixner

sh idle: rename global pm_idle to static sh_idle

2013-02-18T04:34:59+00:00

SH idle code could use some simplification.
This patch enables that by guaranteeing
that "sh_idle" is local, and thus architecture specific.

Signed-off-by: Len Brown 
Cc: linux-sh@vger.kernel.org

sh: Remove cpu_idle_wait()

2012-05-08T10:35:07+00:00

cpuidle uses generic kick_all_cpus_sync() now. Remove the unused code.

Signed-off-by: Thomas Gleixner 
Cc: Peter Zijlstra 
Cc: Paul Mundt 
Link: http://lkml.kernel.org/r/20120507175652.461648208@linutronix.de

sh: fix up fallout from system.h disintegration.

2012-03-30T10:29:57+00:00

Quite a bit of fallout all over the place, nothing terribly exciting.

Signed-off-by: Paul Mundt

Disintegrate asm/system.h for SH

2012-03-28T17:30:03+00:00

Disintegrate asm/system.h for SH.

Signed-off-by: David Howells 
cc: linux-sh@vger.kernel.org

sched/rt: Use schedule_preempt_disabled()

2012-03-01T09:28:03+00:00

Coccinelle based conversion.

Signed-off-by: Thomas Gleixner 
Acked-by: Peter Zijlstra 
Link: http://lkml.kernel.org/n/tip-24swm5zut3h9c4a6s46x8rws@git.kernel.org
Signed-off-by: Ingo Molnar

nohz: Remove tick_nohz_idle_enter_norcu() / tick_nohz_idle_exit_norcu()

2011-12-11T18:31:57+00:00

Those two APIs were provided to optimize the calls of
tick_nohz_idle_enter() and rcu_idle_enter() into a single
irq disabled section. This way no interrupt happening in-between would
needlessly process any RCU job.

Now we are talking about an optimization for which benefits
have yet to be measured. Let's start simple and completely decouple
idle rcu and dyntick idle logics to simplify.

Signed-off-by: Frederic Weisbecker 
Cc: Ingo Molnar 
Cc: Thomas Gleixner 
Cc: Peter Zijlstra 
Reviewed-by: Josh Triplett 
Signed-off-by: Paul E. McKenney

nohz: Allow rcu extended quiescent state handling seperately from tick stop

2011-12-11T18:31:36+00:00

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 
Cc: Mike Frysinger 
Cc: Guan Xuetao 
Cc: David Miller 
Cc: Chris Metcalf 
Cc: Hans-Christian Egtvedt 
Cc: Ralf Baechle 
Cc: Paul E. McKenney 
Cc: Ingo Molnar 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: H. Peter Anvin 
Cc: Russell King 
Cc: Paul Mackerras 
Cc: Heiko Carstens 
Cc: Paul Mundt 
Signed-off-by: Paul E. McKenney

nohz: Separate out irq exit and idle loop dyntick logic

2011-12-11T18:31:35+00:00

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 
Cc: Mike Frysinger 
Cc: Guan Xuetao 
Cc: David Miller 
Cc: Chris Metcalf 
Cc: Hans-Christian Egtvedt 
Cc: Ralf Baechle 
Cc: Paul E. McKenney 
Cc: Ingo Molnar 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: H. Peter Anvin 
Cc: Russell King 
Cc: Paul Mackerras 
Cc: Heiko Carstens 
Cc: Paul Mundt 
Signed-off-by: Paul E. McKenney 
Reviewed-by: Josh Triplett