From 4fa20439a80c008d33f2865b0db94dcb5da467e2 Mon Sep 17 00:00:00 2001 From: Nicolas Pitre Date: Mon, 1 Aug 2011 17:25:06 -0400 Subject: [PATCH] ARM: clean up idle handlers Let's factor out the need_resched() check instead of having it duplicated in every pm_idle implementations to avoid inconsistencies (omap2_pm_idle is missing it already). The forceful re-enablement of IRQs after pm_idle has returned can go. The warning certainly doesn't trigger for existing users. To get rid of the pm_idle calling convention oddity, let's introduce arm_pm_idle() allowing for the local_irq_enable() to be factored out from SOC specific implementations. The default pm_idle function becomes a wrapper for arm_pm_idle and it takes care of enabling IRQs closer to where they are initially disabled. And finally move the comment explaining the reason for that turning off of IRQs to a more proper location. Signed-off-by: Nicolas Pitre Acked-and-tested-by: Jamie Iles --- arch/arm/include/asm/system.h | 1 + arch/arm/kernel/process.c | 23 +++++++++++++++-------- 2 files changed, 16 insertions(+), 8 deletions(-) diff --git a/arch/arm/include/asm/system.h b/arch/arm/include/asm/system.h index e4c96cc6ec0c..424aa458c487 100644 --- a/arch/arm/include/asm/system.h +++ b/arch/arm/include/asm/system.h @@ -110,6 +110,7 @@ extern void cpu_init(void); void soft_restart(unsigned long); extern void (*arm_pm_restart)(char str, const char *cmd); +extern void (*arm_pm_idle)(void); #define UDBG_UNDEFINED (1 << 0) #define UDBG_SYSCALL (1 << 1) diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index 971d65c253a9..ba9e7ef92bec 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -181,12 +181,16 @@ void cpu_idle_wait(void) EXPORT_SYMBOL_GPL(cpu_idle_wait); /* - * This is our default idle handler. We need to disable - * interrupts here to ensure we don't miss a wakeup call. + * This is our default idle handler. */ + +void (*arm_pm_idle)(void); + static void default_idle(void) { - if (!need_resched()) + if (arm_pm_idle) + arm_pm_idle(); + else arch_idle(); local_irq_enable(); } @@ -215,6 +219,10 @@ void cpu_idle(void) cpu_die(); #endif + /* + * We need to disable interrupts here + * to ensure we don't miss a wakeup call. + */ local_irq_disable(); #ifdef CONFIG_PL310_ERRATA_769419 wmb(); @@ -222,19 +230,18 @@ void cpu_idle(void) if (hlt_counter) { local_irq_enable(); cpu_relax(); - } else { + } else if (!need_resched()) { stop_critical_timings(); if (cpuidle_idle_call()) pm_idle(); start_critical_timings(); /* - * This will eventually be removed - pm_idle - * functions should always return with IRQs - * enabled. + * pm_idle functions must always + * return with IRQs enabled. */ WARN_ON(irqs_disabled()); + } else local_irq_enable(); - } } leds_event(led_idle_end); rcu_idle_exit(); -- 2.20.1