From 2e906655baf1c6f6fccd212fc9e6499dc6928b80 Mon Sep 17 00:00:00 2001 From: "venkatesh.pallipadi@intel.com" Date: Thu, 31 Jan 2008 17:35:03 -0800 Subject: [PATCH] ACPI: idle: Fix acpi_safe_halt usages and interrupt enabling/disabling acpi_safe_halt() needs interrupts to be disabled for atomic need_resched check and safe halt. Otherwise we may miss an interrupt and go into halt. acpi_safe_halt() also does not enable interrupts on all return paths. So the callers should handle enable and disable interrupts around it. Signed-off-by: Venkatesh Pallipadi Signed-off-by: Len Brown --- drivers/acpi/processor_idle.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c index 199ea2146153..106a22948aa9 100644 --- a/drivers/acpi/processor_idle.c +++ b/drivers/acpi/processor_idle.c @@ -201,6 +201,10 @@ static inline u32 ticks_elapsed_in_us(u32 t1, u32 t2) return PM_TIMER_TICKS_TO_US((0xFFFFFFFF - t1) + t2); } +/* + * Callers should disable interrupts before the call and enable + * interrupts after return. + */ static void acpi_safe_halt(void) { current_thread_info()->status &= ~TS_POLLING; @@ -413,6 +417,8 @@ static void acpi_processor_idle(void) pm_idle_save(); else acpi_safe_halt(); + + local_irq_enable(); return; } @@ -521,6 +527,7 @@ static void acpi_processor_idle(void) * skew otherwise. */ sleep_ticks = 0xFFFFFFFF; + local_irq_enable(); break; case ACPI_STATE_C2: @@ -1403,11 +1410,13 @@ static int acpi_idle_enter_c1(struct cpuidle_device *dev, if (unlikely(!pr)) return 0; + local_irq_disable(); if (pr->flags.bm_check) acpi_idle_update_bm_rld(pr, cx); acpi_safe_halt(); + local_irq_enable(); cx->usage++; return 0; @@ -1517,7 +1526,9 @@ static int acpi_idle_enter_bm(struct cpuidle_device *dev, if (dev->safe_state) { return dev->safe_state->enter(dev, dev->safe_state); } else { + local_irq_disable(); acpi_safe_halt(); + local_irq_enable(); return 0; } } -- 2.30.2