From 20ff51a36b2cd25ee7eb3216b6d02b68935435ba Mon Sep 17 00:00:00 2001 From: Colin Cross Date: Mon, 7 May 2012 17:57:42 -0700 Subject: cpuidle: coupled: add parallel barrier function Adds cpuidle_coupled_parallel_barrier, which can be used by coupled cpuidle state enter functions to handle resynchronization after determining if any cpu needs to abort. The normal use case will be: static bool abort_flag; static atomic_t abort_barrier; int arch_cpuidle_enter(struct cpuidle_device *dev, ...) { if (arch_turn_off_irq_controller()) { /* returns an error if an irq is pending and would be lost if idle continued and turned off power */ abort_flag = true; } cpuidle_coupled_parallel_barrier(dev, &abort_barrier); if (abort_flag) { /* One of the cpus didn't turn off it's irq controller */ arch_turn_on_irq_controller(); return -EINTR; } /* continue with idle */ ... } This will cause all cpus to abort idle together if one of them needs to abort. Reviewed-by: Santosh Shilimkar Tested-by: Santosh Shilimkar Reviewed-by: Kevin Hilman Tested-by: Kevin Hilman Signed-off-by: Colin Cross Signed-off-by: Len Brown --- include/linux/cpuidle.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'include/linux/cpuidle.h') diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h index 603844835bc7..5ab7183313ce 100644 --- a/include/linux/cpuidle.h +++ b/include/linux/cpuidle.h @@ -183,6 +183,10 @@ static inline int cpuidle_play_dead(void) {return -ENODEV; } #endif +#ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED +void cpuidle_coupled_parallel_barrier(struct cpuidle_device *dev, atomic_t *a); +#endif + /****************************** * CPUIDLE GOVERNOR INTERFACE * ******************************/ -- cgit v1.2.1