diff options
Diffstat (limited to 'kernel/irq/manage.c')
| -rw-r--r-- | kernel/irq/manage.c | 306 |
1 files changed, 195 insertions, 111 deletions
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index f9744853b656..0eebaeef317b 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -115,6 +115,14 @@ EXPORT_SYMBOL(synchronize_irq); #ifdef CONFIG_SMP cpumask_var_t irq_default_affinity; +static int __irq_can_set_affinity(struct irq_desc *desc) +{ + if (!desc || !irqd_can_balance(&desc->irq_data) || + !desc->irq_data.chip || !desc->irq_data.chip->irq_set_affinity) + return 0; + return 1; +} + /** * irq_can_set_affinity - Check if the affinity of a given irq can be set * @irq: Interrupt to check @@ -122,13 +130,7 @@ cpumask_var_t irq_default_affinity; */ int irq_can_set_affinity(unsigned int irq) { - struct irq_desc *desc = irq_to_desc(irq); - - if (!desc || !irqd_can_balance(&desc->irq_data) || - !desc->irq_data.chip || !desc->irq_data.chip->irq_set_affinity) - return 0; - - return 1; + return __irq_can_set_affinity(irq_to_desc(irq)); } /** @@ -190,7 +192,7 @@ int irq_do_set_affinity(struct irq_data *data, const struct cpumask *mask, switch (ret) { case IRQ_SET_MASK_OK: case IRQ_SET_MASK_OK_DONE: - cpumask_copy(data->affinity, mask); + cpumask_copy(desc->irq_common_data.affinity, mask); case IRQ_SET_MASK_OK_NOCOPY: irq_set_thread_affinity(desc); ret = 0; @@ -256,37 +258,6 @@ int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m) } EXPORT_SYMBOL_GPL(irq_set_affinity_hint); -/** - * irq_set_vcpu_affinity - Set vcpu affinity for the interrupt - * @irq: interrupt number to set affinity - * @vcpu_info: vCPU specific data - * - * This function uses the vCPU specific data to set the vCPU - * affinity for an irq. The vCPU specific data is passed from - * outside, such as KVM. One example code path is as below: - * KVM -> IOMMU -> irq_set_vcpu_affinity(). - */ -int irq_set_vcpu_affinity(unsigned int irq, void *vcpu_info) -{ - unsigned long flags; - struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0); - struct irq_data *data; - struct irq_chip *chip; - int ret = -ENOSYS; - - if (!desc) - return -EINVAL; - - data = irq_desc_get_irq_data(desc); - chip = irq_data_get_irq_chip(data); - if (chip && chip->irq_set_vcpu_affinity) - ret = chip->irq_set_vcpu_affinity(data, vcpu_info); - irq_put_desc_unlock(desc, flags); - - return ret; -} -EXPORT_SYMBOL_GPL(irq_set_vcpu_affinity); - static void irq_affinity_notify(struct work_struct *work) { struct irq_affinity_notify *notify = @@ -302,7 +273,7 @@ static void irq_affinity_notify(struct work_struct *work) if (irq_move_pending(&desc->irq_data)) irq_get_pending(cpumask, desc); else - cpumask_copy(cpumask, desc->irq_data.affinity); + cpumask_copy(cpumask, desc->irq_common_data.affinity); raw_spin_unlock_irqrestore(&desc->lock, flags); notify->notify(notify, cpumask); @@ -359,14 +330,13 @@ EXPORT_SYMBOL_GPL(irq_set_affinity_notifier); /* * Generic version of the affinity autoselector. */ -static int -setup_affinity(unsigned int irq, struct irq_desc *desc, struct cpumask *mask) +static int setup_affinity(struct irq_desc *desc, struct cpumask *mask) { struct cpumask *set = irq_default_affinity; int node = irq_desc_get_node(desc); /* Excludes PER_CPU and NO_BALANCE interrupts */ - if (!irq_can_set_affinity(irq)) + if (!__irq_can_set_affinity(desc)) return 0; /* @@ -374,9 +344,9 @@ setup_affinity(unsigned int irq, struct irq_desc *desc, struct cpumask *mask) * one of the targets is online. */ if (irqd_has_set(&desc->irq_data, IRQD_AFFINITY_SET)) { - if (cpumask_intersects(desc->irq_data.affinity, + if (cpumask_intersects(desc->irq_common_data.affinity, cpu_online_mask)) - set = desc->irq_data.affinity; + set = desc->irq_common_data.affinity; else irqd_clear(&desc->irq_data, IRQD_AFFINITY_SET); } @@ -393,10 +363,10 @@ setup_affinity(unsigned int irq, struct irq_desc *desc, struct cpumask *mask) return 0; } #else -static inline int -setup_affinity(unsigned int irq, struct irq_desc *d, struct cpumask *mask) +/* Wrapper for ALPHA specific affinity selector magic */ +static inline int setup_affinity(struct irq_desc *d, struct cpumask *mask) { - return irq_select_affinity(irq); + return irq_select_affinity(irq_desc_get_irq(d)); } #endif @@ -410,20 +380,51 @@ int irq_select_affinity_usr(unsigned int irq, struct cpumask *mask) int ret; raw_spin_lock_irqsave(&desc->lock, flags); - ret = setup_affinity(irq, desc, mask); + ret = setup_affinity(desc, mask); raw_spin_unlock_irqrestore(&desc->lock, flags); return ret; } #else static inline int -setup_affinity(unsigned int irq, struct irq_desc *desc, struct cpumask *mask) +setup_affinity(struct irq_desc *desc, struct cpumask *mask) { return 0; } #endif -void __disable_irq(struct irq_desc *desc, unsigned int irq) +/** + * irq_set_vcpu_affinity - Set vcpu affinity for the interrupt + * @irq: interrupt number to set affinity + * @vcpu_info: vCPU specific data + * + * This function uses the vCPU specific data to set the vCPU + * affinity for an irq. The vCPU specific data is passed from + * outside, such as KVM. One example code path is as below: + * KVM -> IOMMU -> irq_set_vcpu_affinity(). + */ +int irq_set_vcpu_affinity(unsigned int irq, void *vcpu_info) +{ + unsigned long flags; + struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0); + struct irq_data *data; + struct irq_chip *chip; + int ret = -ENOSYS; + + if (!desc) + return -EINVAL; + + data = irq_desc_get_irq_data(desc); + chip = irq_data_get_irq_chip(data); + if (chip && chip->irq_set_vcpu_affinity) + ret = chip->irq_set_vcpu_affinity(data, vcpu_info); + irq_put_desc_unlock(desc, flags); + + return ret; +} +EXPORT_SYMBOL_GPL(irq_set_vcpu_affinity); + +void __disable_irq(struct irq_desc *desc) { if (!desc->depth++) irq_disable(desc); @@ -436,7 +437,7 @@ static int __disable_irq_nosync(unsigned int irq) if (!desc) return -EINVAL; - __disable_irq(desc, irq); + __disable_irq(desc); irq_put_desc_busunlock(desc, flags); return 0; } @@ -503,12 +504,13 @@ bool disable_hardirq(unsigned int irq) } EXPORT_SYMBOL_GPL(disable_hardirq); -void __enable_irq(struct irq_desc *desc, unsigned int irq) +void __enable_irq(struct irq_desc *desc) { switch (desc->depth) { case 0: err_out: - WARN(1, KERN_WARNING "Unbalanced enable for IRQ %d\n", irq); + WARN(1, KERN_WARNING "Unbalanced enable for IRQ %d\n", + irq_desc_get_irq(desc)); break; case 1: { if (desc->istate & IRQS_SUSPENDED) @@ -516,7 +518,7 @@ void __enable_irq(struct irq_desc *desc, unsigned int irq) /* Prevent probing on this irq: */ irq_settings_set_noprobe(desc); irq_enable(desc); - check_irq_resend(desc, irq); + check_irq_resend(desc); /* fall-through */ } default: @@ -546,7 +548,7 @@ void enable_irq(unsigned int irq) KERN_ERR "enable_irq before setup/request_irq: irq %u\n", irq)) goto out; - __enable_irq(desc, irq); + __enable_irq(desc); out: irq_put_desc_busunlock(desc, flags); } @@ -637,8 +639,7 @@ int can_request_irq(unsigned int irq, unsigned long irqflags) return canrequest; } -int __irq_set_trigger(struct irq_desc *desc, unsigned int irq, - unsigned long flags) +int __irq_set_trigger(struct irq_desc *desc, unsigned long flags) { struct irq_chip *chip = desc->irq_data.chip; int ret, unmask = 0; @@ -648,7 +649,8 @@ int __irq_set_trigger(struct irq_desc *desc, unsigned int irq, * IRQF_TRIGGER_* but the PIC does not support multiple * flow-types? */ - pr_debug("No set_type function for IRQ %d (%s)\n", irq, + pr_debug("No set_type function for IRQ %d (%s)\n", + irq_desc_get_irq(desc), chip ? (chip->name ? : "unknown") : "unknown"); return 0; } @@ -685,7 +687,7 @@ int __irq_set_trigger(struct irq_desc *desc, unsigned int irq, break; default: pr_err("Setting trigger mode %lu for irq %u failed (%pF)\n", - flags, irq, chip->irq_set_type); + flags, irq_desc_get_irq(desc), chip->irq_set_type); } if (unmask) unmask_irq(desc); @@ -728,6 +730,12 @@ static irqreturn_t irq_nested_primary_handler(int irq, void *dev_id) return IRQ_NONE; } +static irqreturn_t irq_forced_secondary_handler(int irq, void *dev_id) +{ + WARN(1, "Secondary action handler called for irq %d\n", irq); + return IRQ_NONE; +} + static int irq_wait_for_interrupt(struct irqaction *action) { set_current_state(TASK_INTERRUPTIBLE); @@ -754,7 +762,8 @@ static int irq_wait_for_interrupt(struct irqaction *action) static void irq_finalize_oneshot(struct irq_desc *desc, struct irqaction *action) { - if (!(desc->istate & IRQS_ONESHOT)) + if (!(desc->istate & IRQS_ONESHOT) || + action->handler == irq_forced_secondary_handler) return; again: chip_bus_lock(desc); @@ -827,8 +836,8 @@ irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action) * This code is triggered unconditionally. Check the affinity * mask pointer. For CPU_MASK_OFFSTACK=n this is optimized out. */ - if (desc->irq_data.affinity) - cpumask_copy(mask, desc->irq_data.affinity); + if (desc->irq_common_data.affinity) + cpumask_copy(mask, desc->irq_common_data.affinity); else valid = false; raw_spin_unlock_irq(&desc->lock); @@ -908,6 +917,18 @@ static void irq_thread_dtor(struct callback_head *unused) irq_finalize_oneshot(desc, action); } +static void irq_wake_secondary(struct irq_desc *desc, struct irqaction *action) +{ + struct irqaction *secondary = action->secondary; + + if (WARN_ON_ONCE(!secondary)) + return; + + raw_spin_lock_irq(&desc->lock); + __irq_wake_thread(desc, secondary); + raw_spin_unlock_irq(&desc->lock); +} + /* * Interrupt handler thread */ @@ -938,6 +959,8 @@ static int irq_thread(void *data) action_ret = handler_fn(desc, action); if (action_ret == IRQ_HANDLED) atomic_inc(&desc->threads_handled); + if (action_ret == IRQ_WAKE_THREAD) + irq_wake_secondary(desc, action); wake_threads_waitq(desc); } @@ -982,20 +1005,36 @@ void irq_wake_thread(unsigned int irq, void *dev_id) } EXPORT_SYMBOL_GPL(irq_wake_thread); -static void irq_setup_forced_threading(struct irqaction *new) +static int irq_setup_forced_threading(struct irqaction *new) { if (!force_irqthreads) - return; + return 0; if (new->flags & (IRQF_NO_THREAD | IRQF_PERCPU | IRQF_ONESHOT)) - return; + return 0; new->flags |= IRQF_ONESHOT; - if (!new->thread_fn) { - set_bit(IRQTF_FORCED_THREAD, &new->thread_flags); - new->thread_fn = new->handler; - new->handler = irq_default_primary_handler; + /* + * Handle the case where we have a real primary handler and a + * thread handler. We force thread them as well by creating a + * secondary action. + */ + if (new->handler != irq_default_primary_handler && new->thread_fn) { + /* Allocate the secondary action */ + new->secondary = kzalloc(sizeof(struct irqaction), GFP_KERNEL); + if (!new->secondary) + return -ENOMEM; + new->secondary->handler = irq_forced_secondary_handler; + new->secondary->thread_fn = new->thread_fn; + new->secondary->dev_id = new->dev_id; + new->secondary->irq = new->irq; + new->secondary->name = new->name; } + /* Deal with the primary handler */ + set_bit(IRQTF_FORCED_THREAD, &new->thread_flags); + new->thread_fn = new->handler; + new->handler = irq_default_primary_handler; + return 0; } static int irq_request_resources(struct irq_desc *desc) @@ -1015,6 +1054,48 @@ static void irq_release_resources(struct irq_desc *desc) c->irq_release_resources(d); } +static int +setup_irq_thread(struct irqaction *new, unsigned int irq, bool secondary) +{ + struct task_struct *t; + struct sched_param param = { + .sched_priority = MAX_USER_RT_PRIO/2, + }; + + if (!secondary) { + t = kthread_create(irq_thread, new, "irq/%d-%s", irq, + new->name); + } else { + t = kthread_create(irq_thread, new, "irq/%d-s-%s", irq, + new->name); + param.sched_priority -= 1; + } + + if (IS_ERR(t)) + return PTR_ERR(t); + + sched_setscheduler_nocheck(t, SCHED_FIFO, ¶m); + + /* + * We keep the reference to the task struct even if + * the thread dies to avoid that the interrupt code + * references an already freed task_struct. + */ + get_task_struct(t); + new->thread = t; + /* + * Tell the thread to set its affinity. This is + * important for shared interrupt handlers as we do + * not invoke setup_affinity() for the secondary + * handlers as everything is already set up. Even for + * interrupts marked with IRQF_NO_BALANCE this is + * correct as we want the thread to move to the cpu(s) + * on which the requesting code placed the interrupt. + */ + set_bit(IRQTF_AFFINITY, &new->thread_flags); + return 0; +} + /* * Internal function to register an irqaction - typically used to * allocate special interrupts that are part of the architecture. @@ -1035,6 +1116,8 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) if (!try_module_get(desc->owner)) return -ENODEV; + new->irq = irq; + /* * Check whether the interrupt nests into another interrupt * thread. @@ -1052,8 +1135,11 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) */ new->handler = irq_nested_primary_handler; } else { - if (irq_settings_can_thread(desc)) - irq_setup_forced_threading(new); + if (irq_settings_can_thread(desc)) { + ret = irq_setup_forced_threading(new); + if (ret) + goto out_mput; + } } /* @@ -1062,37 +1148,14 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) * thread. */ if (new->thread_fn && !nested) { - struct task_struct *t; - static const struct sched_param param = { - .sched_priority = MAX_USER_RT_PRIO/2, - }; - - t = kthread_create(irq_thread, new, "irq/%d-%s", irq, - new->name); - if (IS_ERR(t)) { - ret = PTR_ERR(t); + ret = setup_irq_thread(new, irq, false); + if (ret) goto out_mput; + if (new->secondary) { + ret = setup_irq_thread(new->secondary, irq, true); + if (ret) + goto out_thread; } - - sched_setscheduler_nocheck(t, SCHED_FIFO, ¶m); - - /* - * We keep the reference to the task struct even if - * the thread dies to avoid that the interrupt code - * references an already freed task_struct. - */ - get_task_struct(t); - new->thread = t; - /* - * Tell the thread to set its affinity. This is - * important for shared interrupt handlers as we do - * not invoke setup_affinity() for the secondary - * handlers as everything is already set up. Even for - * interrupts marked with IRQF_NO_BALANCE this is - * correct as we want the thread to move to the cpu(s) - * on which the requesting code placed the interrupt. - */ - set_bit(IRQTF_AFFINITY, &new->thread_flags); } if (!alloc_cpumask_var(&mask, GFP_KERNEL)) { @@ -1221,8 +1284,8 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) /* Setup the type (level, edge polarity) if configured: */ if (new->flags & IRQF_TRIGGER_MASK) { - ret = __irq_set_trigger(desc, irq, - new->flags & IRQF_TRIGGER_MASK); + ret = __irq_set_trigger(desc, + new->flags & IRQF_TRIGGER_MASK); if (ret) goto out_mask; @@ -1253,7 +1316,7 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) } /* Set default affinity mask once everything is setup */ - setup_affinity(irq, desc, mask); + setup_affinity(desc, mask); } else if (new->flags & IRQF_TRIGGER_MASK) { unsigned int nmsk = new->flags & IRQF_TRIGGER_MASK; @@ -1265,7 +1328,6 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) irq, nmsk, omsk); } - new->irq = irq; *old_ptr = new; irq_pm_install_action(desc, new); @@ -1280,7 +1342,7 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) */ if (shared && (desc->istate & IRQS_SPURIOUS_DISABLED)) { desc->istate &= ~IRQS_SPURIOUS_DISABLED; - __enable_irq(desc, irq); + __enable_irq(desc); } raw_spin_unlock_irqrestore(&desc->lock, flags); @@ -1291,6 +1353,8 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) */ if (new->thread) wake_up_process(new->thread); + if (new->secondary) + wake_up_process(new->secondary->thread); register_irq_proc(irq, desc); new->dir = NULL; @@ -1321,6 +1385,13 @@ out_thread: kthread_stop(t); put_task_struct(t); } + if (new->secondary && new->secondary->thread) { + struct task_struct *t = new->secondary->thread; + + new->secondary->thread = NULL; + kthread_stop(t); + put_task_struct(t); + } out_mput: module_put(desc->owner); return ret; @@ -1392,6 +1463,7 @@ static struct irqaction *__free_irq(unsigned int irq, void *dev_id) /* If this was the last handler, shut down the IRQ line: */ if (!desc->action) { + irq_settings_clr_disable_unlazy(desc); irq_shutdown(desc); irq_release_resources(desc); } @@ -1428,9 +1500,14 @@ static struct irqaction *__free_irq(unsigned int irq, void *dev_id) if (action->thread) { kthread_stop(action->thread); put_task_struct(action->thread); + if (action->secondary && action->secondary->thread) { + kthread_stop(action->secondary->thread); + put_task_struct(action->secondary->thread); + } } module_put(desc->owner); + kfree(action->secondary); return action; } @@ -1574,8 +1651,10 @@ int request_threaded_irq(unsigned int irq, irq_handler_t handler, retval = __setup_irq(irq, desc, action); chip_bus_sync_unlock(desc); - if (retval) + if (retval) { + kfree(action->secondary); kfree(action); + } #ifdef CONFIG_DEBUG_SHIRQ_FIXME if (!retval && (irqflags & IRQF_SHARED)) { @@ -1650,7 +1729,7 @@ void enable_percpu_irq(unsigned int irq, unsigned int type) if (type != IRQ_TYPE_NONE) { int ret; - ret = __irq_set_trigger(desc, irq, type); + ret = __irq_set_trigger(desc, type); if (ret) { WARN(1, "failed to set type for IRQ%d\n", irq); @@ -1759,6 +1838,7 @@ void free_percpu_irq(unsigned int irq, void __percpu *dev_id) kfree(__free_percpu_irq(irq, dev_id)); chip_bus_sync_unlock(desc); } +EXPORT_SYMBOL_GPL(free_percpu_irq); /** * setup_percpu_irq - setup a per-cpu interrupt @@ -1788,9 +1868,10 @@ int setup_percpu_irq(unsigned int irq, struct irqaction *act) * @devname: An ascii name for the claiming device * @dev_id: A percpu cookie passed back to the handler function * - * This call allocates interrupt resources, but doesn't - * automatically enable the interrupt. It has to be done on each - * CPU using enable_percpu_irq(). + * This call allocates interrupt resources and enables the + * interrupt on the local CPU. If the interrupt is supposed to be + * enabled on other CPUs, it has to be done on each CPU using + * enable_percpu_irq(). * * Dev_id must be globally unique. It is a per-cpu variable, and * the handler gets called with the interrupted CPU's instance of @@ -1829,6 +1910,7 @@ int request_percpu_irq(unsigned int irq, irq_handler_t handler, return retval; } +EXPORT_SYMBOL_GPL(request_percpu_irq); /** * irq_get_irqchip_state - returns the irqchip state of a interrupt. @@ -1875,6 +1957,7 @@ int irq_get_irqchip_state(unsigned int irq, enum irqchip_irq_state which, irq_put_desc_busunlock(desc, flags); return err; } +EXPORT_SYMBOL_GPL(irq_get_irqchip_state); /** * irq_set_irqchip_state - set the state of a forwarded interrupt. @@ -1920,3 +2003,4 @@ int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which, irq_put_desc_busunlock(desc, flags); return err; } +EXPORT_SYMBOL_GPL(irq_set_irqchip_state); |
