From c80081b9209713e0fe86d3def395a9fc66503c58 Mon Sep 17 00:00:00 2001 From: Daniel Lezcano Date: Thu, 6 Jul 2017 14:29:04 +0200 Subject: genirq: Allow to pass the IRQF_TIMER flag with percpu irq request The irq timings infrastructure tracks when interrupts occur in order to statistically predict te next interrupt event. There is no point to track timer interrupts and try to predict them because the next expiration time is already known. This can be avoided via the IRQF_TIMER flag which is passed by timer drivers in request_irq(). It marks the interrupt as timer based which alloes to ignore these interrupts in the timings code. Per CPU interrupts which are requested via request_percpu_+irq() have no flag argument, so marking per cpu timer interrupts is not possible and they get tracked pointlessly. Add __request_percpu_irq() as a variant of request_percpu_irq() with a flags argument and make request_percpu_irq() an inline wrapper passing flags = 0. The flag parameter is restricted to IRQF_TIMER as all other IRQF_ flags make no sense for per cpu interrupts. The next step is to convert all existing users of request_percpu_irq() and then remove the wrapper and the underscores. [ tglx: Massaged changelog ] Signed-off-by: Daniel Lezcano Signed-off-by: Thomas Gleixner Cc: peterz@infradead.org Cc: nicolas.pitre@linaro.org Cc: vincent.guittot@linaro.org Cc: rafael@kernel.org Link: http://lkml.kernel.org/r/1499344144-3964-1-git-send-email-daniel.lezcano@linaro.org --- kernel/irq/manage.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) (limited to 'kernel/irq/manage.c') diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index 91e1f2390752..5624b2dd6b58 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -1950,9 +1950,10 @@ int setup_percpu_irq(unsigned int irq, struct irqaction *act) } /** - * request_percpu_irq - allocate a percpu interrupt line + * __request_percpu_irq - allocate a percpu interrupt line * @irq: Interrupt line to allocate * @handler: Function to be called when the IRQ occurs. + * @flags: Interrupt type flags (IRQF_TIMER only) * @devname: An ascii name for the claiming device * @dev_id: A percpu cookie passed back to the handler function * @@ -1965,8 +1966,9 @@ int setup_percpu_irq(unsigned int irq, struct irqaction *act) * the handler gets called with the interrupted CPU's instance of * that variable. */ -int request_percpu_irq(unsigned int irq, irq_handler_t handler, - const char *devname, void __percpu *dev_id) +int __request_percpu_irq(unsigned int irq, irq_handler_t handler, + unsigned long flags, const char *devname, + void __percpu *dev_id) { struct irqaction *action; struct irq_desc *desc; @@ -1980,12 +1982,15 @@ int request_percpu_irq(unsigned int irq, irq_handler_t handler, !irq_settings_is_per_cpu_devid(desc)) return -EINVAL; + if (flags && flags != IRQF_TIMER) + return -EINVAL; + action = kzalloc(sizeof(struct irqaction), GFP_KERNEL); if (!action) return -ENOMEM; action->handler = handler; - action->flags = IRQF_PERCPU | IRQF_NO_SUSPEND; + action->flags = flags | IRQF_PERCPU | IRQF_NO_SUSPEND; action->name = devname; action->percpu_dev_id = dev_id; @@ -2004,7 +2009,7 @@ int request_percpu_irq(unsigned int irq, irq_handler_t handler, return retval; } -EXPORT_SYMBOL_GPL(request_percpu_irq); +EXPORT_SYMBOL_GPL(__request_percpu_irq); /** * irq_get_irqchip_state - returns the irqchip state of a interrupt. -- cgit v1.2.3