From c3d7acd0273edf0ee50ccf85167acd7ae0759eda Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Fri, 29 Aug 2014 13:46:08 +0200 Subject: genirq: Distangle edge handler entry If the interrupt is disabled or has no action, then we should not call the poll check. Separate the checks. Signed-off-by: Thomas Gleixner Signed-off-by: Rafael J. Wysocki --- kernel/irq/chip.c | 39 +++++++++++++++++++++++++++++---------- 1 file changed, 29 insertions(+), 10 deletions(-) (limited to 'kernel/irq/chip.c') diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index a2b28a2fd7b1..f10c2e58a786 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -540,19 +540,29 @@ handle_edge_irq(unsigned int irq, struct irq_desc *desc) raw_spin_lock(&desc->lock); desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING); + /* - * If we're currently running this IRQ, or its disabled, - * we shouldn't process the IRQ. Mark it pending, handle - * the necessary masking and go out + * If the handler is currently running, mark it pending, + * handle the necessary masking and go out */ - if (unlikely(irqd_irq_disabled(&desc->irq_data) || - irqd_irq_inprogress(&desc->irq_data) || !desc->action)) { + if (unlikely(irqd_irq_inprogress(&desc->irq_data))) { if (!irq_check_poll(desc)) { desc->istate |= IRQS_PENDING; mask_ack_irq(desc); goto out_unlock; } } + + /* + * If its disabled or no action available then mask it and get + * out of here. + */ + if (irqd_irq_disabled(&desc->irq_data) || !desc->action) { + desc->istate |= IRQS_PENDING; + mask_ack_irq(desc); + goto out_unlock; + } + kstat_incr_irqs_this_cpu(irq, desc); /* Start handling the irq */ @@ -601,18 +611,27 @@ void handle_edge_eoi_irq(unsigned int irq, struct irq_desc *desc) raw_spin_lock(&desc->lock); desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING); + /* - * If we're currently running this IRQ, or its disabled, - * we shouldn't process the IRQ. Mark it pending, handle - * the necessary masking and go out + * If the handler is currently running, mark it pending, + * handle the necessary masking and go out */ - if (unlikely(irqd_irq_disabled(&desc->irq_data) || - irqd_irq_inprogress(&desc->irq_data) || !desc->action)) { + if (unlikely(irqd_irq_inprogress(&desc->irq_data))) { if (!irq_check_poll(desc)) { desc->istate |= IRQS_PENDING; goto out_eoi; } } + + /* + * If its disabled or no action available then mask it and get + * out of here. + */ + if (irqd_irq_disabled(&desc->irq_data) || !desc->action) { + desc->istate |= IRQS_PENDING; + goto out_eoi; + } + kstat_incr_irqs_this_cpu(irq, desc); do { -- cgit v1.2.3 From c7bd3ec0531aa636ad57ed9f27e637cbd247e64a Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Fri, 29 Aug 2014 13:39:37 +0200 Subject: genirq: Create helper for flow handler entry check All flow handlers - except the per cpu ones - check for an interrupt in progress and an eventual concurrent polling on another cpu. Create a helper function for the repeated code pattern. Signed-off-by: Thomas Gleixner Signed-off-by: Rafael J. Wysocki --- kernel/irq/chip.c | 48 ++++++++++++++++++++---------------------------- 1 file changed, 20 insertions(+), 28 deletions(-) (limited to 'kernel/irq/chip.c') diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index f10c2e58a786..6baf86085571 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -342,6 +342,13 @@ static bool irq_check_poll(struct irq_desc *desc) return irq_wait_for_poll(desc); } +static bool irq_may_run(struct irq_desc *desc) +{ + if (!irqd_irq_inprogress(&desc->irq_data)) + return true; + return irq_check_poll(desc); +} + /** * handle_simple_irq - Simple and software-decoded IRQs. * @irq: the interrupt number @@ -359,9 +366,8 @@ handle_simple_irq(unsigned int irq, struct irq_desc *desc) { raw_spin_lock(&desc->lock); - if (unlikely(irqd_irq_inprogress(&desc->irq_data))) - if (!irq_check_poll(desc)) - goto out_unlock; + if (!irq_may_run(desc)) + goto out_unlock; desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING); kstat_incr_irqs_this_cpu(irq, desc); @@ -412,9 +418,8 @@ handle_level_irq(unsigned int irq, struct irq_desc *desc) raw_spin_lock(&desc->lock); mask_ack_irq(desc); - if (unlikely(irqd_irq_inprogress(&desc->irq_data))) - if (!irq_check_poll(desc)) - goto out_unlock; + if (!irq_may_run(desc)) + goto out_unlock; desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING); kstat_incr_irqs_this_cpu(irq, desc); @@ -485,9 +490,8 @@ handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc) raw_spin_lock(&desc->lock); - if (unlikely(irqd_irq_inprogress(&desc->irq_data))) - if (!irq_check_poll(desc)) - goto out; + if (!irq_may_run(desc)) + goto out; desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING); kstat_incr_irqs_this_cpu(irq, desc); @@ -541,16 +545,10 @@ handle_edge_irq(unsigned int irq, struct irq_desc *desc) desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING); - /* - * If the handler is currently running, mark it pending, - * handle the necessary masking and go out - */ - if (unlikely(irqd_irq_inprogress(&desc->irq_data))) { - if (!irq_check_poll(desc)) { - desc->istate |= IRQS_PENDING; - mask_ack_irq(desc); - goto out_unlock; - } + if (!irq_may_run(desc)) { + desc->istate |= IRQS_PENDING; + mask_ack_irq(desc); + goto out_unlock; } /* @@ -612,15 +610,9 @@ void handle_edge_eoi_irq(unsigned int irq, struct irq_desc *desc) desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING); - /* - * If the handler is currently running, mark it pending, - * handle the necessary masking and go out - */ - if (unlikely(irqd_irq_inprogress(&desc->irq_data))) { - if (!irq_check_poll(desc)) { - desc->istate |= IRQS_PENDING; - goto out_eoi; - } + if (!irq_may_run(desc)) { + desc->istate |= IRQS_PENDING; + goto out_eoi; } /* -- cgit v1.2.3 From 9ce7a25849e80cfb264f4995f832b932c1987e1a Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Fri, 29 Aug 2014 14:00:16 +0200 Subject: genirq: Simplify wakeup mechanism Currently we suspend wakeup interrupts by lazy disabling them and check later whether the interrupt has fired, but that's not sufficient for suspend to idle as there is no way to check that once we transitioned into the CPU idle state. So we change the mechanism in the following way: 1) Leave the wakeup interrupts enabled across suspend 2) Add a check to irq_may_run() which is called at the beginning of each flow handler whether the interrupt is an armed wakeup source. This check is basically free as it just extends the existing check for IRQD_IRQ_INPROGRESS. So no new conditional in the hot path. If the IRQD_WAKEUP_ARMED flag is set, then the interrupt is disabled, marked as pending/suspended and the pm core is notified about the wakeup event. Signed-off-by: Thomas Gleixner [ rjw: syscore.c and put irq_pm_check_wakeup() into pm.c ] Signed-off-by: Rafael J. Wysocki --- drivers/base/syscore.c | 7 +++--- include/linux/interrupt.h | 5 ----- kernel/irq/chip.c | 20 ++++++++++++++++- kernel/irq/internals.h | 2 ++ kernel/irq/pm.c | 55 +++++++++++++++++++++++++---------------------- 5 files changed, 53 insertions(+), 36 deletions(-) (limited to 'kernel/irq/chip.c') diff --git a/drivers/base/syscore.c b/drivers/base/syscore.c index dbb8350ea8dc..8d98a329f6ea 100644 --- a/drivers/base/syscore.c +++ b/drivers/base/syscore.c @@ -9,7 +9,7 @@ #include #include #include -#include +#include #include static LIST_HEAD(syscore_ops_list); @@ -54,9 +54,8 @@ int syscore_suspend(void) pr_debug("Checking wakeup interrupts\n"); /* Return error code if there are any wakeup interrupts pending. */ - ret = check_wakeup_irqs(); - if (ret) - return ret; + if (pm_wakeup_pending()) + return -EBUSY; WARN_ONCE(!irqs_disabled(), "Interrupts enabled before system core suspend.\n"); diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h index 698ad053d064..69517a24bc50 100644 --- a/include/linux/interrupt.h +++ b/include/linux/interrupt.h @@ -193,11 +193,6 @@ extern void irq_wake_thread(unsigned int irq, void *dev_id); /* The following three functions are for the core kernel use only. */ extern void suspend_device_irqs(void); extern void resume_device_irqs(void); -#ifdef CONFIG_PM_SLEEP -extern int check_wakeup_irqs(void); -#else -static inline int check_wakeup_irqs(void) { return 0; } -#endif /** * struct irq_affinity_notify - context for notification of IRQ affinity changes diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index 6baf86085571..e7917ff8a486 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -344,8 +344,26 @@ static bool irq_check_poll(struct irq_desc *desc) static bool irq_may_run(struct irq_desc *desc) { - if (!irqd_irq_inprogress(&desc->irq_data)) + unsigned int mask = IRQD_IRQ_INPROGRESS | IRQD_WAKEUP_ARMED; + + /* + * If the interrupt is not in progress and is not an armed + * wakeup interrupt, proceed. + */ + if (!irqd_has_set(&desc->irq_data, mask)) return true; + + /* + * If the interrupt is an armed wakeup source, mark it pending + * and suspended, disable it and notify the pm core about the + * event. + */ + if (irq_pm_check_wakeup(desc)) + return false; + + /* + * Handle a potential concurrent poll on a different core. + */ return irq_check_poll(desc); } diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h index c402502a5111..4332d766619d 100644 --- a/kernel/irq/internals.h +++ b/kernel/irq/internals.h @@ -196,9 +196,11 @@ static inline void kstat_incr_irqs_this_cpu(unsigned int irq, struct irq_desc *d } #ifdef CONFIG_PM_SLEEP +bool irq_pm_check_wakeup(struct irq_desc *desc); void irq_pm_install_action(struct irq_desc *desc, struct irqaction *action); void irq_pm_remove_action(struct irq_desc *desc, struct irqaction *action); #else +static inline bool irq_pm_check_wakeup(struct irq_desc *desc) { return false; } static inline void irq_pm_install_action(struct irq_desc *desc, struct irqaction *action) { } static inline void diff --git a/kernel/irq/pm.c b/kernel/irq/pm.c index 766930eaeed9..3ca532592704 100644 --- a/kernel/irq/pm.c +++ b/kernel/irq/pm.c @@ -9,10 +9,24 @@ #include #include #include +#include #include #include "internals.h" +bool irq_pm_check_wakeup(struct irq_desc *desc) +{ + if (irqd_is_wakeup_armed(&desc->irq_data)) { + irqd_clear(&desc->irq_data, IRQD_WAKEUP_ARMED); + desc->istate |= IRQS_SUSPENDED | IRQS_PENDING; + desc->depth++; + irq_disable(desc); + pm_system_wakeup(); + return true; + } + return false; +} + /* * Called from __setup_irq() with desc->lock held after @action has * been installed in the action chain. @@ -54,8 +68,16 @@ static bool suspend_device_irq(struct irq_desc *desc, int irq) if (!desc->action || desc->no_suspend_depth) return false; - if (irqd_is_wakeup_set(&desc->irq_data)) + if (irqd_is_wakeup_set(&desc->irq_data)) { irqd_set(&desc->irq_data, IRQD_WAKEUP_ARMED); + /* + * We return true here to force the caller to issue + * synchronize_irq(). We need to make sure that the + * IRQD_WAKEUP_ARMED is visible before we return from + * suspend_device_irqs(). + */ + return true; + } desc->istate |= IRQS_SUSPENDED; __disable_irq(desc, irq); @@ -79,9 +101,13 @@ static bool suspend_device_irq(struct irq_desc *desc, int irq) * for this purpose. * * So we disable all interrupts and mark them IRQS_SUSPENDED except - * for those which are unused and those which are marked as not + * for those which are unused, those which are marked as not * suspendable via an interrupt request with the flag IRQF_NO_SUSPEND - * set. + * set and those which are marked as active wakeup sources. + * + * The active wakeup sources are handled by the flow handler entry + * code which checks for the IRQD_WAKEUP_ARMED flag, suspends the + * interrupt and notifies the pm core about the wakeup. */ void suspend_device_irqs(void) { @@ -173,26 +199,3 @@ void resume_device_irqs(void) resume_irqs(false); } EXPORT_SYMBOL_GPL(resume_device_irqs); - -/** - * check_wakeup_irqs - check if any wake-up interrupts are pending - */ -int check_wakeup_irqs(void) -{ - struct irq_desc *desc; - int irq; - - for_each_irq_desc(irq, desc) { - /* - * Only interrupts which are marked as wakeup source - * and have not been disabled before the suspend check - * can abort suspend. - */ - if (irqd_is_wakeup_set(&desc->irq_data)) { - if (desc->depth == 1 && desc->istate & IRQS_PENDING) - return -EBUSY; - } - } - - return 0; -} -- cgit v1.2.3