diff options
-rw-r--r-- | MAINTAINERS | 8 | ||||
-rw-r--r-- | arch/arm/mach-mvebu/armada-370-xp.h | 2 | ||||
-rw-r--r-- | arch/arm/mach-mvebu/platsmp.c | 8 | ||||
-rw-r--r-- | drivers/irqchip/irq-armada-370-xp.c | 24 | ||||
-rw-r--r-- | drivers/irqchip/irq-orion.c | 4 | ||||
-rw-r--r-- | include/linux/interrupt.h | 5 | ||||
-rw-r--r-- | include/linux/irqdesc.h | 4 | ||||
-rw-r--r-- | kernel/irq/manage.c | 4 | ||||
-rw-r--r-- | kernel/irq/spurious.c | 106 |
9 files changed, 145 insertions, 20 deletions
diff --git a/MAINTAINERS b/MAINTAINERS index 51ebb779c5f3..b85f6451044f 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -4818,6 +4818,14 @@ L: linux-kernel@vger.kernel.org S: Maintained T: git git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git irq/core F: kernel/irq/ + +IRQCHIP DRIVERS +M: Thomas Gleixner <tglx@linutronix.de> +M: Jason Cooper <jason@lakedaemon.net> +L: linux-kernel@vger.kernel.org +S: Maintained +T: git git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git irq/core +T: git git://git.infradead.org/users/jcooper/linux.git irqchip/core F: drivers/irqchip/ IRQ DOMAINS (IRQ NUMBER MAPPING LIBRARY) diff --git a/arch/arm/mach-mvebu/armada-370-xp.h b/arch/arm/mach-mvebu/armada-370-xp.h index 237c86b83390..c3465f5b1250 100644 --- a/arch/arm/mach-mvebu/armada-370-xp.h +++ b/arch/arm/mach-mvebu/armada-370-xp.h @@ -20,8 +20,6 @@ #define ARMADA_XP_MAX_CPUS 4 -void armada_mpic_send_doorbell(const struct cpumask *mask, unsigned int irq); -void armada_xp_mpic_smp_cpu_init(void); void armada_xp_secondary_startup(void); extern struct smp_operations armada_xp_smp_ops; #endif diff --git a/arch/arm/mach-mvebu/platsmp.c b/arch/arm/mach-mvebu/platsmp.c index a6da03f5b24e..e43727f391f7 100644 --- a/arch/arm/mach-mvebu/platsmp.c +++ b/arch/arm/mach-mvebu/platsmp.c @@ -70,11 +70,6 @@ static void __init set_secondary_cpus_clock(void) } } -static void armada_xp_secondary_init(unsigned int cpu) -{ - armada_xp_mpic_smp_cpu_init(); -} - static int armada_xp_boot_secondary(unsigned int cpu, struct task_struct *idle) { pr_info("Booting CPU %d\n", cpu); @@ -90,8 +85,6 @@ static void __init armada_xp_smp_init_cpus(void) if (ncores == 0 || ncores > ARMADA_XP_MAX_CPUS) panic("Invalid number of CPUs in DT\n"); - - set_smp_cross_call(armada_mpic_send_doorbell); } static void __init armada_xp_smp_prepare_cpus(unsigned int max_cpus) @@ -124,7 +117,6 @@ static void __init armada_xp_smp_prepare_cpus(unsigned int max_cpus) struct smp_operations armada_xp_smp_ops __initdata = { .smp_init_cpus = armada_xp_smp_init_cpus, .smp_prepare_cpus = armada_xp_smp_prepare_cpus, - .smp_secondary_init = armada_xp_secondary_init, .smp_boot_secondary = armada_xp_boot_secondary, #ifdef CONFIG_HOTPLUG_CPU .cpu_die = armada_xp_cpu_die, diff --git a/drivers/irqchip/irq-armada-370-xp.c b/drivers/irqchip/irq-armada-370-xp.c index 3899ba7821c5..c887e6eebc41 100644 --- a/drivers/irqchip/irq-armada-370-xp.c +++ b/drivers/irqchip/irq-armada-370-xp.c @@ -19,6 +19,7 @@ #include <linux/irq.h> #include <linux/interrupt.h> #include <linux/irqchip/chained_irq.h> +#include <linux/cpu.h> #include <linux/io.h> #include <linux/of_address.h> #include <linux/of_irq.h> @@ -310,7 +311,8 @@ static int armada_370_xp_mpic_irq_map(struct irq_domain *h, } #ifdef CONFIG_SMP -void armada_mpic_send_doorbell(const struct cpumask *mask, unsigned int irq) +static void armada_mpic_send_doorbell(const struct cpumask *mask, + unsigned int irq) { int cpu; unsigned long map = 0; @@ -330,7 +332,7 @@ void armada_mpic_send_doorbell(const struct cpumask *mask, unsigned int irq) ARMADA_370_XP_SW_TRIG_INT_OFFS); } -void armada_xp_mpic_smp_cpu_init(void) +static void armada_xp_mpic_smp_cpu_init(void) { /* Clear pending IPIs */ writel(0, per_cpu_int_base + ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS); @@ -342,6 +344,20 @@ void armada_xp_mpic_smp_cpu_init(void) /* Unmask IPI interrupt */ writel(0, per_cpu_int_base + ARMADA_370_XP_INT_CLEAR_MASK_OFFS); } + +static int armada_xp_mpic_secondary_init(struct notifier_block *nfb, + unsigned long action, void *hcpu) +{ + if (action == CPU_STARTING || action == CPU_STARTING_FROZEN) + armada_xp_mpic_smp_cpu_init(); + return NOTIFY_OK; +} + +static struct notifier_block armada_370_xp_mpic_cpu_notifier = { + .notifier_call = armada_xp_mpic_secondary_init, + .priority = 100, +}; + #endif /* CONFIG_SMP */ static struct irq_domain_ops armada_370_xp_mpic_irq_ops = { @@ -497,6 +513,10 @@ static int __init armada_370_xp_mpic_of_init(struct device_node *node, if (parent_irq <= 0) { irq_set_default_host(armada_370_xp_mpic_domain); set_handle_irq(armada_370_xp_handle_irq); +#ifdef CONFIG_SMP + set_smp_cross_call(armada_mpic_send_doorbell); + register_cpu_notifier(&armada_370_xp_mpic_cpu_notifier); +#endif } else { irq_set_chained_handler(parent_irq, armada_370_xp_mpic_handle_cascade_irq); diff --git a/drivers/irqchip/irq-orion.c b/drivers/irqchip/irq-orion.c index e25f246cd2fb..34d18b48bb78 100644 --- a/drivers/irqchip/irq-orion.c +++ b/drivers/irqchip/irq-orion.c @@ -42,7 +42,7 @@ __exception_irq_entry orion_handle_irq(struct pt_regs *regs) u32 stat = readl_relaxed(gc->reg_base + ORION_IRQ_CAUSE) & gc->mask_cache; while (stat) { - u32 hwirq = ffs(stat) - 1; + u32 hwirq = __fls(stat); u32 irq = irq_find_mapping(orion_irq_domain, gc->irq_base + hwirq); handle_IRQ(irq, regs); @@ -117,7 +117,7 @@ static void orion_bridge_irq_handler(unsigned int irq, struct irq_desc *desc) gc->mask_cache; while (stat) { - u32 hwirq = ffs(stat) - 1; + u32 hwirq = __fls(stat); generic_handle_irq(irq_find_mapping(d, gc->irq_base + hwirq)); stat &= ~(1 << hwirq); diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h index 97ac926c78a7..051c85032f48 100644 --- a/include/linux/interrupt.h +++ b/include/linux/interrupt.h @@ -272,6 +272,11 @@ static inline int irq_set_affinity(unsigned int irq, const struct cpumask *m) return -EINVAL; } +static inline int irq_force_affinity(unsigned int irq, const struct cpumask *cpumask) +{ + return 0; +} + static inline int irq_can_set_affinity(unsigned int irq) { return 0; diff --git a/include/linux/irqdesc.h b/include/linux/irqdesc.h index 26e2661d3935..472c021a2d4f 100644 --- a/include/linux/irqdesc.h +++ b/include/linux/irqdesc.h @@ -27,6 +27,8 @@ struct irq_desc; * @irq_count: stats field to detect stalled irqs * @last_unhandled: aging timer for unhandled count * @irqs_unhandled: stats field for spurious unhandled interrupts + * @threads_handled: stats field for deferred spurious detection of threaded handlers + * @threads_handled_last: comparator field for deferred spurious detection of theraded handlers * @lock: locking for SMP * @affinity_hint: hint to user space for preferred irq affinity * @affinity_notify: context for notification of affinity changes @@ -52,6 +54,8 @@ struct irq_desc { unsigned int irq_count; /* For detecting broken IRQs */ unsigned long last_unhandled; /* Aging timer for unhandled count */ unsigned int irqs_unhandled; + atomic_t threads_handled; + int threads_handled_last; raw_spinlock_t lock; struct cpumask *percpu_enabled; #ifdef CONFIG_SMP diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index d34131ca372b..3dc6a61bf06a 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -886,8 +886,8 @@ static int irq_thread(void *data) irq_thread_check_affinity(desc, action); action_ret = handler_fn(desc, action); - if (!noirqdebug) - note_interrupt(action->irq, desc, action_ret); + if (action_ret == IRQ_HANDLED) + atomic_inc(&desc->threads_handled); wake_threads_waitq(desc); } diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c index a1d8cc63b56e..e2514b0e439e 100644 --- a/kernel/irq/spurious.c +++ b/kernel/irq/spurious.c @@ -270,6 +270,8 @@ try_misrouted_irq(unsigned int irq, struct irq_desc *desc, return action && (action->flags & IRQF_IRQPOLL); } +#define SPURIOUS_DEFERRED 0x80000000 + void note_interrupt(unsigned int irq, struct irq_desc *desc, irqreturn_t action_ret) { @@ -277,15 +279,111 @@ void note_interrupt(unsigned int irq, struct irq_desc *desc, irq_settings_is_polled(desc)) return; - /* we get here again via the threaded handler */ - if (action_ret == IRQ_WAKE_THREAD) - return; - if (bad_action_ret(action_ret)) { report_bad_irq(irq, desc, action_ret); return; } + /* + * We cannot call note_interrupt from the threaded handler + * because we need to look at the compound of all handlers + * (primary and threaded). Aside of that in the threaded + * shared case we have no serialization against an incoming + * hardware interrupt while we are dealing with a threaded + * result. + * + * So in case a thread is woken, we just note the fact and + * defer the analysis to the next hardware interrupt. + * + * The threaded handlers store whether they sucessfully + * handled an interrupt and we check whether that number + * changed versus the last invocation. + * + * We could handle all interrupts with the delayed by one + * mechanism, but for the non forced threaded case we'd just + * add pointless overhead to the straight hardirq interrupts + * for the sake of a few lines less code. + */ + if (action_ret & IRQ_WAKE_THREAD) { + /* + * There is a thread woken. Check whether one of the + * shared primary handlers returned IRQ_HANDLED. If + * not we defer the spurious detection to the next + * interrupt. + */ + if (action_ret == IRQ_WAKE_THREAD) { + int handled; + /* + * We use bit 31 of thread_handled_last to + * denote the deferred spurious detection + * active. No locking necessary as + * thread_handled_last is only accessed here + * and we have the guarantee that hard + * interrupts are not reentrant. + */ + if (!(desc->threads_handled_last & SPURIOUS_DEFERRED)) { + desc->threads_handled_last |= SPURIOUS_DEFERRED; + return; + } + /* + * Check whether one of the threaded handlers + * returned IRQ_HANDLED since the last + * interrupt happened. + * + * For simplicity we just set bit 31, as it is + * set in threads_handled_last as well. So we + * avoid extra masking. And we really do not + * care about the high bits of the handled + * count. We just care about the count being + * different than the one we saw before. + */ + handled = atomic_read(&desc->threads_handled); + handled |= SPURIOUS_DEFERRED; + if (handled != desc->threads_handled_last) { + action_ret = IRQ_HANDLED; + /* + * Note: We keep the SPURIOUS_DEFERRED + * bit set. We are handling the + * previous invocation right now. + * Keep it for the current one, so the + * next hardware interrupt will + * account for it. + */ + desc->threads_handled_last = handled; + } else { + /* + * None of the threaded handlers felt + * responsible for the last interrupt + * + * We keep the SPURIOUS_DEFERRED bit + * set in threads_handled_last as we + * need to account for the current + * interrupt as well. + */ + action_ret = IRQ_NONE; + } + } else { + /* + * One of the primary handlers returned + * IRQ_HANDLED. So we don't care about the + * threaded handlers on the same line. Clear + * the deferred detection bit. + * + * In theory we could/should check whether the + * deferred bit is set and take the result of + * the previous run into account here as + * well. But it's really not worth the + * trouble. If every other interrupt is + * handled we never trigger the spurious + * detector. And if this is just the one out + * of 100k unhandled ones which is handled + * then we merily delay the spurious detection + * by one hard interrupt. Not a real problem. + */ + desc->threads_handled_last &= ~SPURIOUS_DEFERRED; + } + } + if (unlikely(action_ret == IRQ_NONE)) { /* * If we are seeing only the odd spurious IRQ caused by |