From c5e5ec033c4ab25c53f1fd217849e75deb0bf7bf Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 19 May 2020 10:41:00 +0100 Subject: genirq: Add fasteoi IPI flow For irqchips using the fasteoi flow, IPIs are a bit special. They need to be EOI'd early (before calling the handler), as funny things may happen in the handler (they do not necessarily behave like a normal interrupt). Reviewed-by: Valentin Schneider Signed-off-by: Marc Zyngier --- kernel/irq/chip.c | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) (limited to 'kernel/irq') diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index 857f5f4c8098..bed517d5aa4d 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -944,6 +944,33 @@ void handle_percpu_devid_irq(struct irq_desc *desc) chip->irq_eoi(&desc->irq_data); } +/** + * handle_percpu_devid_fasteoi_ipi - Per CPU local IPI handler with per cpu + * dev ids + * @desc: the interrupt description structure for this irq + * + * The biggest difference with the IRQ version is that the interrupt is + * EOIed early, as the IPI could result in a context switch, and we need to + * make sure the IPI can fire again. We also assume that the arch code has + * registered an action. If not, we are positively doomed. + */ +void handle_percpu_devid_fasteoi_ipi(struct irq_desc *desc) +{ + struct irq_chip *chip = irq_desc_get_chip(desc); + struct irqaction *action = desc->action; + unsigned int irq = irq_desc_get_irq(desc); + irqreturn_t res; + + __kstat_incr_irqs_this_cpu(desc); + + if (chip->irq_eoi) + chip->irq_eoi(&desc->irq_data); + + trace_irq_handler_entry(irq, action); + res = action->handler(irq, raw_cpu_ptr(action->percpu_dev_id)); + trace_irq_handler_exit(irq, action, res); +} + /** * handle_percpu_devid_fasteoi_nmi - Per CPU local NMI handler with per cpu * dev ids -- cgit v1.2.3 From 83cfac95c01817819c2a51f0931d798d851f8a08 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 19 May 2020 14:58:13 +0100 Subject: genirq: Allow interrupts to be excluded from /proc/interrupts A number of architectures implement IPI statistics directly, duplicating the core kstat_irqs accounting. As we move IPIs to being actual IRQs, we would end-up with a confusing display in /proc/interrupts (where the IPIs would appear twice). In order to solve this, allow interrupts to be flagged as "hidden", which excludes them from /proc/interrupts. Reviewed-by: Valentin Schneider Signed-off-by: Marc Zyngier --- include/linux/irq.h | 4 +++- kernel/irq/debugfs.c | 1 + kernel/irq/proc.c | 2 +- kernel/irq/settings.h | 7 +++++++ 4 files changed, 12 insertions(+), 2 deletions(-) (limited to 'kernel/irq') diff --git a/include/linux/irq.h b/include/linux/irq.h index 57205bbf46bf..63b9d962ee67 100644 --- a/include/linux/irq.h +++ b/include/linux/irq.h @@ -71,6 +71,7 @@ enum irqchip_irq_state; * it from the spurious interrupt detection * mechanism and from core side polling. * IRQ_DISABLE_UNLAZY - Disable lazy irq disable + * IRQ_HIDDEN - Don't show up in /proc/interrupts */ enum { IRQ_TYPE_NONE = 0x00000000, @@ -97,13 +98,14 @@ enum { IRQ_PER_CPU_DEVID = (1 << 17), IRQ_IS_POLLED = (1 << 18), IRQ_DISABLE_UNLAZY = (1 << 19), + IRQ_HIDDEN = (1 << 20), }; #define IRQF_MODIFY_MASK \ (IRQ_TYPE_SENSE_MASK | IRQ_NOPROBE | IRQ_NOREQUEST | \ IRQ_NOAUTOEN | IRQ_MOVE_PCNTXT | IRQ_LEVEL | IRQ_NO_BALANCING | \ IRQ_PER_CPU | IRQ_NESTED_THREAD | IRQ_NOTHREAD | IRQ_PER_CPU_DEVID | \ - IRQ_IS_POLLED | IRQ_DISABLE_UNLAZY) + IRQ_IS_POLLED | IRQ_DISABLE_UNLAZY | IRQ_HIDDEN) #define IRQ_NO_BALANCING_MASK (IRQ_PER_CPU | IRQ_NO_BALANCING) diff --git a/kernel/irq/debugfs.c b/kernel/irq/debugfs.c index b95ff5d5f4bd..acabc0c0e46b 100644 --- a/kernel/irq/debugfs.c +++ b/kernel/irq/debugfs.c @@ -136,6 +136,7 @@ static const struct irq_bit_descr irqdesc_states[] = { BIT_MASK_DESCR(_IRQ_PER_CPU_DEVID), BIT_MASK_DESCR(_IRQ_IS_POLLED), BIT_MASK_DESCR(_IRQ_DISABLE_UNLAZY), + BIT_MASK_DESCR(_IRQ_HIDDEN), }; static const struct irq_bit_descr irqdesc_istates[] = { diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c index 32c071d7bc03..72513ed2a5fc 100644 --- a/kernel/irq/proc.c +++ b/kernel/irq/proc.c @@ -485,7 +485,7 @@ int show_interrupts(struct seq_file *p, void *v) rcu_read_lock(); desc = irq_to_desc(i); - if (!desc) + if (!desc || irq_settings_is_hidden(desc)) goto outsparse; if (desc->kstat_irqs) diff --git a/kernel/irq/settings.h b/kernel/irq/settings.h index e43795cd2ccf..403378b9947b 100644 --- a/kernel/irq/settings.h +++ b/kernel/irq/settings.h @@ -17,6 +17,7 @@ enum { _IRQ_PER_CPU_DEVID = IRQ_PER_CPU_DEVID, _IRQ_IS_POLLED = IRQ_IS_POLLED, _IRQ_DISABLE_UNLAZY = IRQ_DISABLE_UNLAZY, + _IRQ_HIDDEN = IRQ_HIDDEN, _IRQF_MODIFY_MASK = IRQF_MODIFY_MASK, }; @@ -31,6 +32,7 @@ enum { #define IRQ_PER_CPU_DEVID GOT_YOU_MORON #define IRQ_IS_POLLED GOT_YOU_MORON #define IRQ_DISABLE_UNLAZY GOT_YOU_MORON +#define IRQ_HIDDEN GOT_YOU_MORON #undef IRQF_MODIFY_MASK #define IRQF_MODIFY_MASK GOT_YOU_MORON @@ -167,3 +169,8 @@ static inline void irq_settings_clr_disable_unlazy(struct irq_desc *desc) { desc->status_use_accessors &= ~_IRQ_DISABLE_UNLAZY; } + +static inline bool irq_settings_is_hidden(struct irq_desc *desc) +{ + return desc->status_use_accessors & _IRQ_HIDDEN; +} -- cgit v1.2.3