diff options
Diffstat (limited to 'drivers/idle')
| -rw-r--r-- | drivers/idle/intel_idle.c | 154 |
1 files changed, 75 insertions, 79 deletions
diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c index 5adc058c705d..e0332d567735 100644 --- a/drivers/idle/intel_idle.c +++ b/drivers/idle/intel_idle.c @@ -83,10 +83,6 @@ struct idle_cpu { static const struct idle_cpu *icpu; static struct cpuidle_device __percpu *intel_idle_cpuidle_devices; -static int intel_idle(struct cpuidle_device *dev, - struct cpuidle_driver *drv, int index); -static void intel_idle_s2idle(struct cpuidle_device *dev, - struct cpuidle_driver *drv, int index); static struct cpuidle_state *cpuidle_state_table; /* @@ -112,6 +108,81 @@ static struct cpuidle_state *cpuidle_state_table; #define flg2MWAIT(flags) (((flags) >> 24) & 0xFF) #define MWAIT2flg(eax) ((eax & 0xFF) << 24) +/** + * intel_idle - Ask the processor to enter the given idle state. + * @dev: cpuidle device of the target CPU. + * @drv: cpuidle driver (assumed to point to intel_idle_driver). + * @index: Target idle state index. + * + * Use the MWAIT instruction to notify the processor that the CPU represented by + * @dev is idle and it can try to enter the idle state corresponding to @index. + * + * If the local APIC timer is not known to be reliable in the target idle state, + * enable one-shot tick broadcasting for the target CPU before executing MWAIT. + * + * Optionally call leave_mm() for the target CPU upfront to avoid wakeups due to + * flushing user TLBs. + * + * Must be called under local_irq_disable(). + */ +static __cpuidle int intel_idle(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index) +{ + struct cpuidle_state *state = &drv->states[index]; + unsigned long eax = flg2MWAIT(state->flags); + unsigned long ecx = 1; /* break on interrupt flag */ + bool uninitialized_var(tick); + int cpu = smp_processor_id(); + + /* + * leave_mm() to avoid costly and often unnecessary wakeups + * for flushing the user TLB's associated with the active mm. + */ + if (state->flags & CPUIDLE_FLAG_TLB_FLUSHED) + leave_mm(cpu); + + if (!static_cpu_has(X86_FEATURE_ARAT) && !lapic_timer_always_reliable) { + /* + * Switch over to one-shot tick broadcast if the target C-state + * is deeper than C1. + */ + if ((eax >> MWAIT_SUBSTATE_SIZE) & MWAIT_CSTATE_MASK) { + tick = true; + tick_broadcast_enter(); + } else { + tick = false; + } + } + + mwait_idle_with_hints(eax, ecx); + + if (!static_cpu_has(X86_FEATURE_ARAT) && tick) + tick_broadcast_exit(); + + return index; +} + +/** + * intel_idle_s2idle - Ask the processor to enter the given idle state. + * @dev: cpuidle device of the target CPU. + * @drv: cpuidle driver (assumed to point to intel_idle_driver). + * @index: Target idle state index. + * + * Use the MWAIT instruction to notify the processor that the CPU represented by + * @dev is idle and it can try to enter the idle state corresponding to @index. + * + * Invoked as a suspend-to-idle callback routine with frozen user space, frozen + * scheduler tick and suspended scheduler clock on the target CPU. + */ +static __cpuidle void intel_idle_s2idle(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index) +{ + unsigned long eax = flg2MWAIT(drv->states[index].flags); + unsigned long ecx = 1; /* break on interrupt flag */ + + mwait_idle_with_hints(eax, ecx); +} + /* * States are indexed by the cstate number, * which is also the index into the MWAIT hint array. @@ -891,81 +962,6 @@ static struct cpuidle_state dnv_cstates[] = { .enter = NULL } }; -/** - * intel_idle - Ask the processor to enter the given idle state. - * @dev: cpuidle device of the target CPU. - * @drv: cpuidle driver (assumed to point to intel_idle_driver). - * @index: Target idle state index. - * - * Use the MWAIT instruction to notify the processor that the CPU represented by - * @dev is idle and it can try to enter the idle state corresponding to @index. - * - * If the local APIC timer is not known to be reliable in the target idle state, - * enable one-shot tick broadcasting for the target CPU before executing MWAIT. - * - * Optionally call leave_mm() for the target CPU upfront to avoid wakeups due to - * flushing user TLBs. - * - * Must be called under local_irq_disable(). - */ -static __cpuidle int intel_idle(struct cpuidle_device *dev, - struct cpuidle_driver *drv, int index) -{ - struct cpuidle_state *state = &drv->states[index]; - unsigned long eax = flg2MWAIT(state->flags); - unsigned long ecx = 1; /* break on interrupt flag */ - bool uninitialized_var(tick); - int cpu = smp_processor_id(); - - /* - * leave_mm() to avoid costly and often unnecessary wakeups - * for flushing the user TLB's associated with the active mm. - */ - if (state->flags & CPUIDLE_FLAG_TLB_FLUSHED) - leave_mm(cpu); - - if (!static_cpu_has(X86_FEATURE_ARAT) && !lapic_timer_always_reliable) { - /* - * Switch over to one-shot tick broadcast if the target C-state - * is deeper than C1. - */ - if ((eax >> MWAIT_SUBSTATE_SIZE) & MWAIT_CSTATE_MASK) { - tick = true; - tick_broadcast_enter(); - } else { - tick = false; - } - } - - mwait_idle_with_hints(eax, ecx); - - if (!static_cpu_has(X86_FEATURE_ARAT) && tick) - tick_broadcast_exit(); - - return index; -} - -/** - * intel_idle_s2idle - Ask the processor to enter the given idle state. - * @dev: cpuidle device of the target CPU. - * @drv: cpuidle driver (assumed to point to intel_idle_driver). - * @index: Target idle state index. - * - * Use the MWAIT instruction to notify the processor that the CPU represented by - * @dev is idle and it can try to enter the idle state corresponding to @index. - * - * Invoked as a suspend-to-idle callback routine with frozen user space, frozen - * scheduler tick and suspended scheduler clock on the target CPU. - */ -static __cpuidle void intel_idle_s2idle(struct cpuidle_device *dev, - struct cpuidle_driver *drv, int index) -{ - unsigned long eax = flg2MWAIT(drv->states[index].flags); - unsigned long ecx = 1; /* break on interrupt flag */ - - mwait_idle_with_hints(eax, ecx); -} - static const struct idle_cpu idle_cpu_nehalem = { .state_table = nehalem_cstates, .auto_demotion_disable_flags = NHM_C1_AUTO_DEMOTE | NHM_C3_AUTO_DEMOTE, |