2 * linux/kernel/irq/manage.c
4 * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
5 * Copyright (C) 2005-2006 Thomas Gleixner
7 * This file contains driver APIs to the irq subsystem.
10 #define pr_fmt(fmt) "genirq: " fmt
12 #include <linux/irq.h>
13 #include <linux/kthread.h>
14 #include <linux/module.h>
15 #include <linux/random.h>
16 #include <linux/interrupt.h>
17 #include <linux/slab.h>
18 #include <linux/sched.h>
19 #include <linux/sched/rt.h>
20 #include <linux/sched/task.h>
21 #include <uapi/linux/sched/types.h>
22 #include <linux/task_work.h>
24 #include "internals.h"
26 #ifdef CONFIG_IRQ_FORCED_THREADING
27 __read_mostly bool force_irqthreads;
29 static int __init setup_forced_irqthreads(char *arg)
31 force_irqthreads = true;
34 early_param("threadirqs", setup_forced_irqthreads);
37 static void __synchronize_hardirq(struct irq_desc *desc)
45 * Wait until we're out of the critical section. This might
46 * give the wrong answer due to the lack of memory barriers.
48 while (irqd_irq_inprogress(&desc->irq_data))
51 /* Ok, that indicated we're done: double-check carefully. */
52 raw_spin_lock_irqsave(&desc->lock, flags);
53 inprogress = irqd_irq_inprogress(&desc->irq_data);
54 raw_spin_unlock_irqrestore(&desc->lock, flags);
56 /* Oops, that failed? */
61 * synchronize_hardirq - wait for pending hard IRQ handlers (on other CPUs)
62 * @irq: interrupt number to wait for
64 * This function waits for any pending hard IRQ handlers for this
65 * interrupt to complete before returning. If you use this
66 * function while holding a resource the IRQ handler may need you
67 * will deadlock. It does not take associated threaded handlers
70 * Do not use this for shutdown scenarios where you must be sure
71 * that all parts (hardirq and threaded handler) have completed.
73 * Returns: false if a threaded handler is active.
75 * This function may be called - with care - from IRQ context.
77 bool synchronize_hardirq(unsigned int irq)
79 struct irq_desc *desc = irq_to_desc(irq);
82 __synchronize_hardirq(desc);
83 return !atomic_read(&desc->threads_active);
88 EXPORT_SYMBOL(synchronize_hardirq);
91 * synchronize_irq - wait for pending IRQ handlers (on other CPUs)
92 * @irq: interrupt number to wait for
94 * This function waits for any pending IRQ handlers for this interrupt
95 * to complete before returning. If you use this function while
96 * holding a resource the IRQ handler may need you will deadlock.
98 * This function may be called - with care - from IRQ context.
100 void synchronize_irq(unsigned int irq)
102 struct irq_desc *desc = irq_to_desc(irq);
105 __synchronize_hardirq(desc);
107 * We made sure that no hardirq handler is
108 * running. Now verify that no threaded handlers are
111 wait_event(desc->wait_for_threads,
112 !atomic_read(&desc->threads_active));
115 EXPORT_SYMBOL(synchronize_irq);
118 cpumask_var_t irq_default_affinity;
120 static bool __irq_can_set_affinity(struct irq_desc *desc)
122 if (!desc || !irqd_can_balance(&desc->irq_data) ||
123 !desc->irq_data.chip || !desc->irq_data.chip->irq_set_affinity)
129 * irq_can_set_affinity - Check if the affinity of a given irq can be set
130 * @irq: Interrupt to check
133 int irq_can_set_affinity(unsigned int irq)
135 return __irq_can_set_affinity(irq_to_desc(irq));
139 * irq_can_set_affinity_usr - Check if affinity of a irq can be set from user space
140 * @irq: Interrupt to check
142 * Like irq_can_set_affinity() above, but additionally checks for the
143 * AFFINITY_MANAGED flag.
145 bool irq_can_set_affinity_usr(unsigned int irq)
147 struct irq_desc *desc = irq_to_desc(irq);
149 return __irq_can_set_affinity(desc) &&
150 !irqd_affinity_is_managed(&desc->irq_data);
154 * irq_set_thread_affinity - Notify irq threads to adjust affinity
155 * @desc: irq descriptor which has affitnity changed
157 * We just set IRQTF_AFFINITY and delegate the affinity setting
158 * to the interrupt thread itself. We can not call
159 * set_cpus_allowed_ptr() here as we hold desc->lock and this
160 * code can be called from hard interrupt context.
162 void irq_set_thread_affinity(struct irq_desc *desc)
164 struct irqaction *action;
166 for_each_action_of_desc(desc, action)
168 set_bit(IRQTF_AFFINITY, &action->thread_flags);
171 #ifdef CONFIG_GENERIC_PENDING_IRQ
172 static inline bool irq_can_move_pcntxt(struct irq_data *data)
174 return irqd_can_move_in_process_context(data);
176 static inline bool irq_move_pending(struct irq_data *data)
178 return irqd_is_setaffinity_pending(data);
181 irq_copy_pending(struct irq_desc *desc, const struct cpumask *mask)
183 cpumask_copy(desc->pending_mask, mask);
186 irq_get_pending(struct cpumask *mask, struct irq_desc *desc)
188 cpumask_copy(mask, desc->pending_mask);
191 static inline bool irq_can_move_pcntxt(struct irq_data *data) { return true; }
192 static inline bool irq_move_pending(struct irq_data *data) { return false; }
194 irq_copy_pending(struct irq_desc *desc, const struct cpumask *mask) { }
196 irq_get_pending(struct cpumask *mask, struct irq_desc *desc) { }
199 int irq_do_set_affinity(struct irq_data *data, const struct cpumask *mask,
202 struct irq_desc *desc = irq_data_to_desc(data);
203 struct irq_chip *chip = irq_data_get_irq_chip(data);
206 ret = chip->irq_set_affinity(data, mask, force);
208 case IRQ_SET_MASK_OK:
209 case IRQ_SET_MASK_OK_DONE:
210 cpumask_copy(desc->irq_common_data.affinity, mask);
211 case IRQ_SET_MASK_OK_NOCOPY:
212 irq_set_thread_affinity(desc);
219 int irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask,
222 struct irq_chip *chip = irq_data_get_irq_chip(data);
223 struct irq_desc *desc = irq_data_to_desc(data);
226 if (!chip || !chip->irq_set_affinity)
229 if (irq_can_move_pcntxt(data)) {
230 ret = irq_do_set_affinity(data, mask, force);
232 irqd_set_move_pending(data);
233 irq_copy_pending(desc, mask);
236 if (desc->affinity_notify) {
237 kref_get(&desc->affinity_notify->kref);
238 schedule_work(&desc->affinity_notify->work);
240 irqd_set(data, IRQD_AFFINITY_SET);
245 int __irq_set_affinity(unsigned int irq, const struct cpumask *mask, bool force)
247 struct irq_desc *desc = irq_to_desc(irq);
254 raw_spin_lock_irqsave(&desc->lock, flags);
255 ret = irq_set_affinity_locked(irq_desc_get_irq_data(desc), mask, force);
256 raw_spin_unlock_irqrestore(&desc->lock, flags);
260 int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m)
263 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
267 desc->affinity_hint = m;
268 irq_put_desc_unlock(desc, flags);
269 /* set the initial affinity to prevent every interrupt being on CPU0 */
271 __irq_set_affinity(irq, m, false);
274 EXPORT_SYMBOL_GPL(irq_set_affinity_hint);
276 static void irq_affinity_notify(struct work_struct *work)
278 struct irq_affinity_notify *notify =
279 container_of(work, struct irq_affinity_notify, work);
280 struct irq_desc *desc = irq_to_desc(notify->irq);
281 cpumask_var_t cpumask;
284 if (!desc || !alloc_cpumask_var(&cpumask, GFP_KERNEL))
287 raw_spin_lock_irqsave(&desc->lock, flags);
288 if (irq_move_pending(&desc->irq_data))
289 irq_get_pending(cpumask, desc);
291 cpumask_copy(cpumask, desc->irq_common_data.affinity);
292 raw_spin_unlock_irqrestore(&desc->lock, flags);
294 notify->notify(notify, cpumask);
296 free_cpumask_var(cpumask);
298 kref_put(¬ify->kref, notify->release);
302 * irq_set_affinity_notifier - control notification of IRQ affinity changes
303 * @irq: Interrupt for which to enable/disable notification
304 * @notify: Context for notification, or %NULL to disable
305 * notification. Function pointers must be initialised;
306 * the other fields will be initialised by this function.
308 * Must be called in process context. Notification may only be enabled
309 * after the IRQ is allocated and must be disabled before the IRQ is
310 * freed using free_irq().
313 irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify)
315 struct irq_desc *desc = irq_to_desc(irq);
316 struct irq_affinity_notify *old_notify;
319 /* The release function is promised process context */
325 /* Complete initialisation of *notify */
328 kref_init(¬ify->kref);
329 INIT_WORK(¬ify->work, irq_affinity_notify);
332 raw_spin_lock_irqsave(&desc->lock, flags);
333 old_notify = desc->affinity_notify;
334 desc->affinity_notify = notify;
335 raw_spin_unlock_irqrestore(&desc->lock, flags);
338 kref_put(&old_notify->kref, old_notify->release);
342 EXPORT_SYMBOL_GPL(irq_set_affinity_notifier);
344 #ifndef CONFIG_AUTO_IRQ_AFFINITY
346 * Generic version of the affinity autoselector.
348 static int setup_affinity(struct irq_desc *desc, struct cpumask *mask)
350 struct cpumask *set = irq_default_affinity;
351 int node = irq_desc_get_node(desc);
353 /* Excludes PER_CPU and NO_BALANCE interrupts */
354 if (!__irq_can_set_affinity(desc))
358 * Preserve the managed affinity setting and a userspace affinity
359 * setup, but make sure that one of the targets is online.
361 if (irqd_affinity_is_managed(&desc->irq_data) ||
362 irqd_has_set(&desc->irq_data, IRQD_AFFINITY_SET)) {
363 if (cpumask_intersects(desc->irq_common_data.affinity,
365 set = desc->irq_common_data.affinity;
367 irqd_clear(&desc->irq_data, IRQD_AFFINITY_SET);
370 cpumask_and(mask, cpu_online_mask, set);
371 if (node != NUMA_NO_NODE) {
372 const struct cpumask *nodemask = cpumask_of_node(node);
374 /* make sure at least one of the cpus in nodemask is online */
375 if (cpumask_intersects(mask, nodemask))
376 cpumask_and(mask, mask, nodemask);
378 irq_do_set_affinity(&desc->irq_data, mask, false);
382 /* Wrapper for ALPHA specific affinity selector magic */
383 static inline int setup_affinity(struct irq_desc *d, struct cpumask *mask)
385 return irq_select_affinity(irq_desc_get_irq(d));
390 * Called when affinity is set via /proc/irq
392 int irq_select_affinity_usr(unsigned int irq, struct cpumask *mask)
394 struct irq_desc *desc = irq_to_desc(irq);
398 raw_spin_lock_irqsave(&desc->lock, flags);
399 ret = setup_affinity(desc, mask);
400 raw_spin_unlock_irqrestore(&desc->lock, flags);
406 setup_affinity(struct irq_desc *desc, struct cpumask *mask)
413 * irq_set_vcpu_affinity - Set vcpu affinity for the interrupt
414 * @irq: interrupt number to set affinity
415 * @vcpu_info: vCPU specific data
417 * This function uses the vCPU specific data to set the vCPU
418 * affinity for an irq. The vCPU specific data is passed from
419 * outside, such as KVM. One example code path is as below:
420 * KVM -> IOMMU -> irq_set_vcpu_affinity().
422 int irq_set_vcpu_affinity(unsigned int irq, void *vcpu_info)
425 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
426 struct irq_data *data;
427 struct irq_chip *chip;
433 data = irq_desc_get_irq_data(desc);
434 chip = irq_data_get_irq_chip(data);
435 if (chip && chip->irq_set_vcpu_affinity)
436 ret = chip->irq_set_vcpu_affinity(data, vcpu_info);
437 irq_put_desc_unlock(desc, flags);
441 EXPORT_SYMBOL_GPL(irq_set_vcpu_affinity);
443 void __disable_irq(struct irq_desc *desc)
449 static int __disable_irq_nosync(unsigned int irq)
452 struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
457 irq_put_desc_busunlock(desc, flags);
462 * disable_irq_nosync - disable an irq without waiting
463 * @irq: Interrupt to disable
465 * Disable the selected interrupt line. Disables and Enables are
467 * Unlike disable_irq(), this function does not ensure existing
468 * instances of the IRQ handler have completed before returning.
470 * This function may be called from IRQ context.
472 void disable_irq_nosync(unsigned int irq)
474 __disable_irq_nosync(irq);
476 EXPORT_SYMBOL(disable_irq_nosync);
479 * disable_irq - disable an irq and wait for completion
480 * @irq: Interrupt to disable
482 * Disable the selected interrupt line. Enables and Disables are
484 * This function waits for any pending IRQ handlers for this interrupt
485 * to complete before returning. If you use this function while
486 * holding a resource the IRQ handler may need you will deadlock.
488 * This function may be called - with care - from IRQ context.
490 void disable_irq(unsigned int irq)
492 if (!__disable_irq_nosync(irq))
493 synchronize_irq(irq);
495 EXPORT_SYMBOL(disable_irq);
498 * disable_hardirq - disables an irq and waits for hardirq completion
499 * @irq: Interrupt to disable
501 * Disable the selected interrupt line. Enables and Disables are
503 * This function waits for any pending hard IRQ handlers for this
504 * interrupt to complete before returning. If you use this function while
505 * holding a resource the hard IRQ handler may need you will deadlock.
507 * When used to optimistically disable an interrupt from atomic context
508 * the return value must be checked.
510 * Returns: false if a threaded handler is active.
512 * This function may be called - with care - from IRQ context.
514 bool disable_hardirq(unsigned int irq)
516 if (!__disable_irq_nosync(irq))
517 return synchronize_hardirq(irq);
521 EXPORT_SYMBOL_GPL(disable_hardirq);
523 void __enable_irq(struct irq_desc *desc)
525 switch (desc->depth) {
528 WARN(1, KERN_WARNING "Unbalanced enable for IRQ %d\n",
529 irq_desc_get_irq(desc));
532 if (desc->istate & IRQS_SUSPENDED)
534 /* Prevent probing on this irq: */
535 irq_settings_set_noprobe(desc);
537 * Call irq_startup() not irq_enable() here because the
538 * interrupt might be marked NOAUTOEN. So irq_startup()
539 * needs to be invoked when it gets enabled the first
540 * time. If it was already started up, then irq_startup()
541 * will invoke irq_enable() under the hood.
543 irq_startup(desc, true);
552 * enable_irq - enable handling of an irq
553 * @irq: Interrupt to enable
555 * Undoes the effect of one call to disable_irq(). If this
556 * matches the last disable, processing of interrupts on this
557 * IRQ line is re-enabled.
559 * This function may be called from IRQ context only when
560 * desc->irq_data.chip->bus_lock and desc->chip->bus_sync_unlock are NULL !
562 void enable_irq(unsigned int irq)
565 struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
569 if (WARN(!desc->irq_data.chip,
570 KERN_ERR "enable_irq before setup/request_irq: irq %u\n", irq))
575 irq_put_desc_busunlock(desc, flags);
577 EXPORT_SYMBOL(enable_irq);
579 static int set_irq_wake_real(unsigned int irq, unsigned int on)
581 struct irq_desc *desc = irq_to_desc(irq);
584 if (irq_desc_get_chip(desc)->flags & IRQCHIP_SKIP_SET_WAKE)
587 if (desc->irq_data.chip->irq_set_wake)
588 ret = desc->irq_data.chip->irq_set_wake(&desc->irq_data, on);
594 * irq_set_irq_wake - control irq power management wakeup
595 * @irq: interrupt to control
596 * @on: enable/disable power management wakeup
598 * Enable/disable power management wakeup mode, which is
599 * disabled by default. Enables and disables must match,
600 * just as they match for non-wakeup mode support.
602 * Wakeup mode lets this IRQ wake the system from sleep
603 * states like "suspend to RAM".
605 int irq_set_irq_wake(unsigned int irq, unsigned int on)
608 struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
614 /* wakeup-capable irqs can be shared between drivers that
615 * don't need to have the same sleep mode behaviors.
618 if (desc->wake_depth++ == 0) {
619 ret = set_irq_wake_real(irq, on);
621 desc->wake_depth = 0;
623 irqd_set(&desc->irq_data, IRQD_WAKEUP_STATE);
626 if (desc->wake_depth == 0) {
627 WARN(1, "Unbalanced IRQ %d wake disable\n", irq);
628 } else if (--desc->wake_depth == 0) {
629 ret = set_irq_wake_real(irq, on);
631 desc->wake_depth = 1;
633 irqd_clear(&desc->irq_data, IRQD_WAKEUP_STATE);
636 irq_put_desc_busunlock(desc, flags);
639 EXPORT_SYMBOL(irq_set_irq_wake);
642 * Internal function that tells the architecture code whether a
643 * particular irq has been exclusively allocated or is available
646 int can_request_irq(unsigned int irq, unsigned long irqflags)
649 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
655 if (irq_settings_can_request(desc)) {
657 irqflags & desc->action->flags & IRQF_SHARED)
660 irq_put_desc_unlock(desc, flags);
664 int __irq_set_trigger(struct irq_desc *desc, unsigned long flags)
666 struct irq_chip *chip = desc->irq_data.chip;
669 if (!chip || !chip->irq_set_type) {
671 * IRQF_TRIGGER_* but the PIC does not support multiple
674 pr_debug("No set_type function for IRQ %d (%s)\n",
675 irq_desc_get_irq(desc),
676 chip ? (chip->name ? : "unknown") : "unknown");
680 if (chip->flags & IRQCHIP_SET_TYPE_MASKED) {
681 if (!irqd_irq_masked(&desc->irq_data))
683 if (!irqd_irq_disabled(&desc->irq_data))
687 /* Mask all flags except trigger mode */
688 flags &= IRQ_TYPE_SENSE_MASK;
689 ret = chip->irq_set_type(&desc->irq_data, flags);
692 case IRQ_SET_MASK_OK:
693 case IRQ_SET_MASK_OK_DONE:
694 irqd_clear(&desc->irq_data, IRQD_TRIGGER_MASK);
695 irqd_set(&desc->irq_data, flags);
697 case IRQ_SET_MASK_OK_NOCOPY:
698 flags = irqd_get_trigger_type(&desc->irq_data);
699 irq_settings_set_trigger_mask(desc, flags);
700 irqd_clear(&desc->irq_data, IRQD_LEVEL);
701 irq_settings_clr_level(desc);
702 if (flags & IRQ_TYPE_LEVEL_MASK) {
703 irq_settings_set_level(desc);
704 irqd_set(&desc->irq_data, IRQD_LEVEL);
710 pr_err("Setting trigger mode %lu for irq %u failed (%pF)\n",
711 flags, irq_desc_get_irq(desc), chip->irq_set_type);
718 #ifdef CONFIG_HARDIRQS_SW_RESEND
719 int irq_set_parent(int irq, int parent_irq)
722 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
727 desc->parent_irq = parent_irq;
729 irq_put_desc_unlock(desc, flags);
732 EXPORT_SYMBOL_GPL(irq_set_parent);
736 * Default primary interrupt handler for threaded interrupts. Is
737 * assigned as primary handler when request_threaded_irq is called
738 * with handler == NULL. Useful for oneshot interrupts.
740 static irqreturn_t irq_default_primary_handler(int irq, void *dev_id)
742 return IRQ_WAKE_THREAD;
746 * Primary handler for nested threaded interrupts. Should never be
749 static irqreturn_t irq_nested_primary_handler(int irq, void *dev_id)
751 WARN(1, "Primary handler called for nested irq %d\n", irq);
755 static irqreturn_t irq_forced_secondary_handler(int irq, void *dev_id)
757 WARN(1, "Secondary action handler called for irq %d\n", irq);
761 static int irq_wait_for_interrupt(struct irqaction *action)
763 set_current_state(TASK_INTERRUPTIBLE);
765 while (!kthread_should_stop()) {
767 if (test_and_clear_bit(IRQTF_RUNTHREAD,
768 &action->thread_flags)) {
769 __set_current_state(TASK_RUNNING);
773 set_current_state(TASK_INTERRUPTIBLE);
775 __set_current_state(TASK_RUNNING);
780 * Oneshot interrupts keep the irq line masked until the threaded
781 * handler finished. unmask if the interrupt has not been disabled and
784 static void irq_finalize_oneshot(struct irq_desc *desc,
785 struct irqaction *action)
787 if (!(desc->istate & IRQS_ONESHOT) ||
788 action->handler == irq_forced_secondary_handler)
792 raw_spin_lock_irq(&desc->lock);
795 * Implausible though it may be we need to protect us against
796 * the following scenario:
798 * The thread is faster done than the hard interrupt handler
799 * on the other CPU. If we unmask the irq line then the
800 * interrupt can come in again and masks the line, leaves due
801 * to IRQS_INPROGRESS and the irq line is masked forever.
803 * This also serializes the state of shared oneshot handlers
804 * versus "desc->threads_onehsot |= action->thread_mask;" in
805 * irq_wake_thread(). See the comment there which explains the
808 if (unlikely(irqd_irq_inprogress(&desc->irq_data))) {
809 raw_spin_unlock_irq(&desc->lock);
810 chip_bus_sync_unlock(desc);
816 * Now check again, whether the thread should run. Otherwise
817 * we would clear the threads_oneshot bit of this thread which
820 if (test_bit(IRQTF_RUNTHREAD, &action->thread_flags))
823 desc->threads_oneshot &= ~action->thread_mask;
825 if (!desc->threads_oneshot && !irqd_irq_disabled(&desc->irq_data) &&
826 irqd_irq_masked(&desc->irq_data))
827 unmask_threaded_irq(desc);
830 raw_spin_unlock_irq(&desc->lock);
831 chip_bus_sync_unlock(desc);
836 * Check whether we need to change the affinity of the interrupt thread.
839 irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action)
844 if (!test_and_clear_bit(IRQTF_AFFINITY, &action->thread_flags))
848 * In case we are out of memory we set IRQTF_AFFINITY again and
849 * try again next time
851 if (!alloc_cpumask_var(&mask, GFP_KERNEL)) {
852 set_bit(IRQTF_AFFINITY, &action->thread_flags);
856 raw_spin_lock_irq(&desc->lock);
858 * This code is triggered unconditionally. Check the affinity
859 * mask pointer. For CPU_MASK_OFFSTACK=n this is optimized out.
861 if (cpumask_available(desc->irq_common_data.affinity))
862 cpumask_copy(mask, desc->irq_common_data.affinity);
865 raw_spin_unlock_irq(&desc->lock);
868 set_cpus_allowed_ptr(current, mask);
869 free_cpumask_var(mask);
873 irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action) { }
877 * Interrupts which are not explicitely requested as threaded
878 * interrupts rely on the implicit bh/preempt disable of the hard irq
879 * context. So we need to disable bh here to avoid deadlocks and other
883 irq_forced_thread_fn(struct irq_desc *desc, struct irqaction *action)
888 ret = action->thread_fn(action->irq, action->dev_id);
889 irq_finalize_oneshot(desc, action);
895 * Interrupts explicitly requested as threaded interrupts want to be
896 * preemtible - many of them need to sleep and wait for slow busses to
899 static irqreturn_t irq_thread_fn(struct irq_desc *desc,
900 struct irqaction *action)
904 ret = action->thread_fn(action->irq, action->dev_id);
905 irq_finalize_oneshot(desc, action);
909 static void wake_threads_waitq(struct irq_desc *desc)
911 if (atomic_dec_and_test(&desc->threads_active))
912 wake_up(&desc->wait_for_threads);
915 static void irq_thread_dtor(struct callback_head *unused)
917 struct task_struct *tsk = current;
918 struct irq_desc *desc;
919 struct irqaction *action;
921 if (WARN_ON_ONCE(!(current->flags & PF_EXITING)))
924 action = kthread_data(tsk);
926 pr_err("exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n",
927 tsk->comm, tsk->pid, action->irq);
930 desc = irq_to_desc(action->irq);
932 * If IRQTF_RUNTHREAD is set, we need to decrement
933 * desc->threads_active and wake possible waiters.
935 if (test_and_clear_bit(IRQTF_RUNTHREAD, &action->thread_flags))
936 wake_threads_waitq(desc);
938 /* Prevent a stale desc->threads_oneshot */
939 irq_finalize_oneshot(desc, action);
942 static void irq_wake_secondary(struct irq_desc *desc, struct irqaction *action)
944 struct irqaction *secondary = action->secondary;
946 if (WARN_ON_ONCE(!secondary))
949 raw_spin_lock_irq(&desc->lock);
950 __irq_wake_thread(desc, secondary);
951 raw_spin_unlock_irq(&desc->lock);
955 * Interrupt handler thread
957 static int irq_thread(void *data)
959 struct callback_head on_exit_work;
960 struct irqaction *action = data;
961 struct irq_desc *desc = irq_to_desc(action->irq);
962 irqreturn_t (*handler_fn)(struct irq_desc *desc,
963 struct irqaction *action);
965 if (force_irqthreads && test_bit(IRQTF_FORCED_THREAD,
966 &action->thread_flags))
967 handler_fn = irq_forced_thread_fn;
969 handler_fn = irq_thread_fn;
971 init_task_work(&on_exit_work, irq_thread_dtor);
972 task_work_add(current, &on_exit_work, false);
974 irq_thread_check_affinity(desc, action);
976 while (!irq_wait_for_interrupt(action)) {
977 irqreturn_t action_ret;
979 irq_thread_check_affinity(desc, action);
981 action_ret = handler_fn(desc, action);
982 if (action_ret == IRQ_HANDLED)
983 atomic_inc(&desc->threads_handled);
984 if (action_ret == IRQ_WAKE_THREAD)
985 irq_wake_secondary(desc, action);
987 wake_threads_waitq(desc);
991 * This is the regular exit path. __free_irq() is stopping the
992 * thread via kthread_stop() after calling
993 * synchronize_irq(). So neither IRQTF_RUNTHREAD nor the
994 * oneshot mask bit can be set. We cannot verify that as we
995 * cannot touch the oneshot mask at this point anymore as
996 * __setup_irq() might have given out currents thread_mask
999 task_work_cancel(current, irq_thread_dtor);
1004 * irq_wake_thread - wake the irq thread for the action identified by dev_id
1005 * @irq: Interrupt line
1006 * @dev_id: Device identity for which the thread should be woken
1009 void irq_wake_thread(unsigned int irq, void *dev_id)
1011 struct irq_desc *desc = irq_to_desc(irq);
1012 struct irqaction *action;
1013 unsigned long flags;
1015 if (!desc || WARN_ON(irq_settings_is_per_cpu_devid(desc)))
1018 raw_spin_lock_irqsave(&desc->lock, flags);
1019 for_each_action_of_desc(desc, action) {
1020 if (action->dev_id == dev_id) {
1022 __irq_wake_thread(desc, action);
1026 raw_spin_unlock_irqrestore(&desc->lock, flags);
1028 EXPORT_SYMBOL_GPL(irq_wake_thread);
1030 static int irq_setup_forced_threading(struct irqaction *new)
1032 if (!force_irqthreads)
1034 if (new->flags & (IRQF_NO_THREAD | IRQF_PERCPU | IRQF_ONESHOT))
1037 new->flags |= IRQF_ONESHOT;
1040 * Handle the case where we have a real primary handler and a
1041 * thread handler. We force thread them as well by creating a
1044 if (new->handler != irq_default_primary_handler && new->thread_fn) {
1045 /* Allocate the secondary action */
1046 new->secondary = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
1047 if (!new->secondary)
1049 new->secondary->handler = irq_forced_secondary_handler;
1050 new->secondary->thread_fn = new->thread_fn;
1051 new->secondary->dev_id = new->dev_id;
1052 new->secondary->irq = new->irq;
1053 new->secondary->name = new->name;
1055 /* Deal with the primary handler */
1056 set_bit(IRQTF_FORCED_THREAD, &new->thread_flags);
1057 new->thread_fn = new->handler;
1058 new->handler = irq_default_primary_handler;
1062 static int irq_request_resources(struct irq_desc *desc)
1064 struct irq_data *d = &desc->irq_data;
1065 struct irq_chip *c = d->chip;
1067 return c->irq_request_resources ? c->irq_request_resources(d) : 0;
1070 static void irq_release_resources(struct irq_desc *desc)
1072 struct irq_data *d = &desc->irq_data;
1073 struct irq_chip *c = d->chip;
1075 if (c->irq_release_resources)
1076 c->irq_release_resources(d);
1080 setup_irq_thread(struct irqaction *new, unsigned int irq, bool secondary)
1082 struct task_struct *t;
1083 struct sched_param param = {
1084 .sched_priority = MAX_USER_RT_PRIO/2,
1088 t = kthread_create(irq_thread, new, "irq/%d-%s", irq,
1091 t = kthread_create(irq_thread, new, "irq/%d-s-%s", irq,
1093 param.sched_priority -= 1;
1099 sched_setscheduler_nocheck(t, SCHED_FIFO, ¶m);
1102 * We keep the reference to the task struct even if
1103 * the thread dies to avoid that the interrupt code
1104 * references an already freed task_struct.
1109 * Tell the thread to set its affinity. This is
1110 * important for shared interrupt handlers as we do
1111 * not invoke setup_affinity() for the secondary
1112 * handlers as everything is already set up. Even for
1113 * interrupts marked with IRQF_NO_BALANCE this is
1114 * correct as we want the thread to move to the cpu(s)
1115 * on which the requesting code placed the interrupt.
1117 set_bit(IRQTF_AFFINITY, &new->thread_flags);
1122 * Internal function to register an irqaction - typically used to
1123 * allocate special interrupts that are part of the architecture.
1126 __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
1128 struct irqaction *old, **old_ptr;
1129 unsigned long flags, thread_mask = 0;
1130 int ret, nested, shared = 0;
1136 if (desc->irq_data.chip == &no_irq_chip)
1138 if (!try_module_get(desc->owner))
1144 * If the trigger type is not specified by the caller,
1145 * then use the default for this interrupt.
1147 if (!(new->flags & IRQF_TRIGGER_MASK))
1148 new->flags |= irqd_get_trigger_type(&desc->irq_data);
1151 * Check whether the interrupt nests into another interrupt
1154 nested = irq_settings_is_nested_thread(desc);
1156 if (!new->thread_fn) {
1161 * Replace the primary handler which was provided from
1162 * the driver for non nested interrupt handling by the
1163 * dummy function which warns when called.
1165 new->handler = irq_nested_primary_handler;
1167 if (irq_settings_can_thread(desc)) {
1168 ret = irq_setup_forced_threading(new);
1175 * Create a handler thread when a thread function is supplied
1176 * and the interrupt does not nest into another interrupt
1179 if (new->thread_fn && !nested) {
1180 ret = setup_irq_thread(new, irq, false);
1183 if (new->secondary) {
1184 ret = setup_irq_thread(new->secondary, irq, true);
1190 if (!alloc_cpumask_var(&mask, GFP_KERNEL)) {
1196 * Drivers are often written to work w/o knowledge about the
1197 * underlying irq chip implementation, so a request for a
1198 * threaded irq without a primary hard irq context handler
1199 * requires the ONESHOT flag to be set. Some irq chips like
1200 * MSI based interrupts are per se one shot safe. Check the
1201 * chip flags, so we can avoid the unmask dance at the end of
1202 * the threaded handler for those.
1204 if (desc->irq_data.chip->flags & IRQCHIP_ONESHOT_SAFE)
1205 new->flags &= ~IRQF_ONESHOT;
1208 * The following block of code has to be executed atomically
1210 raw_spin_lock_irqsave(&desc->lock, flags);
1211 old_ptr = &desc->action;
1215 * Can't share interrupts unless both agree to and are
1216 * the same type (level, edge, polarity). So both flag
1217 * fields must have IRQF_SHARED set and the bits which
1218 * set the trigger type must match. Also all must
1221 unsigned int oldtype = irqd_get_trigger_type(&desc->irq_data);
1223 if (!((old->flags & new->flags) & IRQF_SHARED) ||
1224 (oldtype != (new->flags & IRQF_TRIGGER_MASK)) ||
1225 ((old->flags ^ new->flags) & IRQF_ONESHOT))
1228 /* All handlers must agree on per-cpuness */
1229 if ((old->flags & IRQF_PERCPU) !=
1230 (new->flags & IRQF_PERCPU))
1233 /* add new interrupt at end of irq queue */
1236 * Or all existing action->thread_mask bits,
1237 * so we can find the next zero bit for this
1240 thread_mask |= old->thread_mask;
1241 old_ptr = &old->next;
1248 * Setup the thread mask for this irqaction for ONESHOT. For
1249 * !ONESHOT irqs the thread mask is 0 so we can avoid a
1250 * conditional in irq_wake_thread().
1252 if (new->flags & IRQF_ONESHOT) {
1254 * Unlikely to have 32 resp 64 irqs sharing one line,
1257 if (thread_mask == ~0UL) {
1262 * The thread_mask for the action is or'ed to
1263 * desc->thread_active to indicate that the
1264 * IRQF_ONESHOT thread handler has been woken, but not
1265 * yet finished. The bit is cleared when a thread
1266 * completes. When all threads of a shared interrupt
1267 * line have completed desc->threads_active becomes
1268 * zero and the interrupt line is unmasked. See
1269 * handle.c:irq_wake_thread() for further information.
1271 * If no thread is woken by primary (hard irq context)
1272 * interrupt handlers, then desc->threads_active is
1273 * also checked for zero to unmask the irq line in the
1274 * affected hard irq flow handlers
1275 * (handle_[fasteoi|level]_irq).
1277 * The new action gets the first zero bit of
1278 * thread_mask assigned. See the loop above which or's
1279 * all existing action->thread_mask bits.
1281 new->thread_mask = 1 << ffz(thread_mask);
1283 } else if (new->handler == irq_default_primary_handler &&
1284 !(desc->irq_data.chip->flags & IRQCHIP_ONESHOT_SAFE)) {
1286 * The interrupt was requested with handler = NULL, so
1287 * we use the default primary handler for it. But it
1288 * does not have the oneshot flag set. In combination
1289 * with level interrupts this is deadly, because the
1290 * default primary handler just wakes the thread, then
1291 * the irq lines is reenabled, but the device still
1292 * has the level irq asserted. Rinse and repeat....
1294 * While this works for edge type interrupts, we play
1295 * it safe and reject unconditionally because we can't
1296 * say for sure which type this interrupt really
1297 * has. The type flags are unreliable as the
1298 * underlying chip implementation can override them.
1300 pr_err("Threaded irq requested with handler=NULL and !ONESHOT for irq %d\n",
1307 ret = irq_request_resources(desc);
1309 pr_err("Failed to request resources for %s (irq %d) on irqchip %s\n",
1310 new->name, irq, desc->irq_data.chip->name);
1314 init_waitqueue_head(&desc->wait_for_threads);
1316 /* Setup the type (level, edge polarity) if configured: */
1317 if (new->flags & IRQF_TRIGGER_MASK) {
1318 ret = __irq_set_trigger(desc,
1319 new->flags & IRQF_TRIGGER_MASK);
1325 desc->istate &= ~(IRQS_AUTODETECT | IRQS_SPURIOUS_DISABLED | \
1326 IRQS_ONESHOT | IRQS_WAITING);
1327 irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS);
1329 if (new->flags & IRQF_PERCPU) {
1330 irqd_set(&desc->irq_data, IRQD_PER_CPU);
1331 irq_settings_set_per_cpu(desc);
1334 if (new->flags & IRQF_ONESHOT)
1335 desc->istate |= IRQS_ONESHOT;
1337 if (irq_settings_can_autoenable(desc)) {
1338 irq_startup(desc, true);
1341 * Shared interrupts do not go well with disabling
1342 * auto enable. The sharing interrupt might request
1343 * it while it's still disabled and then wait for
1344 * interrupts forever.
1346 WARN_ON_ONCE(new->flags & IRQF_SHARED);
1347 /* Undo nested disables: */
1351 /* Exclude IRQ from balancing if requested */
1352 if (new->flags & IRQF_NOBALANCING) {
1353 irq_settings_set_no_balancing(desc);
1354 irqd_set(&desc->irq_data, IRQD_NO_BALANCING);
1357 /* Set default affinity mask once everything is setup */
1358 setup_affinity(desc, mask);
1360 } else if (new->flags & IRQF_TRIGGER_MASK) {
1361 unsigned int nmsk = new->flags & IRQF_TRIGGER_MASK;
1362 unsigned int omsk = irqd_get_trigger_type(&desc->irq_data);
1365 /* hope the handler works with current trigger mode */
1366 pr_warn("irq %d uses trigger mode %u; requested %u\n",
1372 irq_pm_install_action(desc, new);
1374 /* Reset broken irq detection when installing new handler */
1375 desc->irq_count = 0;
1376 desc->irqs_unhandled = 0;
1379 * Check whether we disabled the irq via the spurious handler
1380 * before. Reenable it and give it another chance.
1382 if (shared && (desc->istate & IRQS_SPURIOUS_DISABLED)) {
1383 desc->istate &= ~IRQS_SPURIOUS_DISABLED;
1387 raw_spin_unlock_irqrestore(&desc->lock, flags);
1390 * Strictly no need to wake it up, but hung_task complains
1391 * when no hard interrupt wakes the thread up.
1394 wake_up_process(new->thread);
1396 wake_up_process(new->secondary->thread);
1398 register_irq_proc(irq, desc);
1400 register_handler_proc(irq, new);
1401 free_cpumask_var(mask);
1406 if (!(new->flags & IRQF_PROBE_SHARED)) {
1407 pr_err("Flags mismatch irq %d. %08x (%s) vs. %08x (%s)\n",
1408 irq, new->flags, new->name, old->flags, old->name);
1409 #ifdef CONFIG_DEBUG_SHIRQ
1416 raw_spin_unlock_irqrestore(&desc->lock, flags);
1417 free_cpumask_var(mask);
1421 struct task_struct *t = new->thread;
1427 if (new->secondary && new->secondary->thread) {
1428 struct task_struct *t = new->secondary->thread;
1430 new->secondary->thread = NULL;
1435 module_put(desc->owner);
1440 * setup_irq - setup an interrupt
1441 * @irq: Interrupt line to setup
1442 * @act: irqaction for the interrupt
1444 * Used to statically setup interrupts in the early boot process.
1446 int setup_irq(unsigned int irq, struct irqaction *act)
1449 struct irq_desc *desc = irq_to_desc(irq);
1451 if (!desc || WARN_ON(irq_settings_is_per_cpu_devid(desc)))
1454 retval = irq_chip_pm_get(&desc->irq_data);
1458 chip_bus_lock(desc);
1459 retval = __setup_irq(irq, desc, act);
1460 chip_bus_sync_unlock(desc);
1463 irq_chip_pm_put(&desc->irq_data);
1467 EXPORT_SYMBOL_GPL(setup_irq);
1470 * Internal function to unregister an irqaction - used to free
1471 * regular and special interrupts that are part of the architecture.
1473 static struct irqaction *__free_irq(unsigned int irq, void *dev_id)
1475 struct irq_desc *desc = irq_to_desc(irq);
1476 struct irqaction *action, **action_ptr;
1477 unsigned long flags;
1479 WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);
1484 chip_bus_lock(desc);
1485 raw_spin_lock_irqsave(&desc->lock, flags);
1488 * There can be multiple actions per IRQ descriptor, find the right
1489 * one based on the dev_id:
1491 action_ptr = &desc->action;
1493 action = *action_ptr;
1496 WARN(1, "Trying to free already-free IRQ %d\n", irq);
1497 raw_spin_unlock_irqrestore(&desc->lock, flags);
1498 chip_bus_sync_unlock(desc);
1502 if (action->dev_id == dev_id)
1504 action_ptr = &action->next;
1507 /* Found it - now remove it from the list of entries: */
1508 *action_ptr = action->next;
1510 irq_pm_remove_action(desc, action);
1512 /* If this was the last handler, shut down the IRQ line: */
1513 if (!desc->action) {
1514 irq_settings_clr_disable_unlazy(desc);
1516 irq_release_resources(desc);
1520 /* make sure affinity_hint is cleaned up */
1521 if (WARN_ON_ONCE(desc->affinity_hint))
1522 desc->affinity_hint = NULL;
1525 raw_spin_unlock_irqrestore(&desc->lock, flags);
1526 chip_bus_sync_unlock(desc);
1528 unregister_handler_proc(irq, action);
1530 /* Make sure it's not being used on another CPU: */
1531 synchronize_irq(irq);
1533 #ifdef CONFIG_DEBUG_SHIRQ
1535 * It's a shared IRQ -- the driver ought to be prepared for an IRQ
1536 * event to happen even now it's being freed, so let's make sure that
1537 * is so by doing an extra call to the handler ....
1539 * ( We do this after actually deregistering it, to make sure that a
1540 * 'real' IRQ doesn't run in * parallel with our fake. )
1542 if (action->flags & IRQF_SHARED) {
1543 local_irq_save(flags);
1544 action->handler(irq, dev_id);
1545 local_irq_restore(flags);
1549 if (action->thread) {
1550 kthread_stop(action->thread);
1551 put_task_struct(action->thread);
1552 if (action->secondary && action->secondary->thread) {
1553 kthread_stop(action->secondary->thread);
1554 put_task_struct(action->secondary->thread);
1558 irq_chip_pm_put(&desc->irq_data);
1559 module_put(desc->owner);
1560 kfree(action->secondary);
1565 * remove_irq - free an interrupt
1566 * @irq: Interrupt line to free
1567 * @act: irqaction for the interrupt
1569 * Used to remove interrupts statically setup by the early boot process.
1571 void remove_irq(unsigned int irq, struct irqaction *act)
1573 struct irq_desc *desc = irq_to_desc(irq);
1575 if (desc && !WARN_ON(irq_settings_is_per_cpu_devid(desc)))
1576 __free_irq(irq, act->dev_id);
1578 EXPORT_SYMBOL_GPL(remove_irq);
1581 * free_irq - free an interrupt allocated with request_irq
1582 * @irq: Interrupt line to free
1583 * @dev_id: Device identity to free
1585 * Remove an interrupt handler. The handler is removed and if the
1586 * interrupt line is no longer in use by any driver it is disabled.
1587 * On a shared IRQ the caller must ensure the interrupt is disabled
1588 * on the card it drives before calling this function. The function
1589 * does not return until any executing interrupts for this IRQ
1592 * This function must not be called from interrupt context.
1594 * Returns the devname argument passed to request_irq.
1596 const void *free_irq(unsigned int irq, void *dev_id)
1598 struct irq_desc *desc = irq_to_desc(irq);
1599 struct irqaction *action;
1600 const char *devname;
1602 if (!desc || WARN_ON(irq_settings_is_per_cpu_devid(desc)))
1606 if (WARN_ON(desc->affinity_notify))
1607 desc->affinity_notify = NULL;
1610 action = __free_irq(irq, dev_id);
1611 devname = action->name;
1615 EXPORT_SYMBOL(free_irq);
1618 * request_threaded_irq - allocate an interrupt line
1619 * @irq: Interrupt line to allocate
1620 * @handler: Function to be called when the IRQ occurs.
1621 * Primary handler for threaded interrupts
1622 * If NULL and thread_fn != NULL the default
1623 * primary handler is installed
1624 * @thread_fn: Function called from the irq handler thread
1625 * If NULL, no irq thread is created
1626 * @irqflags: Interrupt type flags
1627 * @devname: An ascii name for the claiming device
1628 * @dev_id: A cookie passed back to the handler function
1630 * This call allocates interrupt resources and enables the
1631 * interrupt line and IRQ handling. From the point this
1632 * call is made your handler function may be invoked. Since
1633 * your handler function must clear any interrupt the board
1634 * raises, you must take care both to initialise your hardware
1635 * and to set up the interrupt handler in the right order.
1637 * If you want to set up a threaded irq handler for your device
1638 * then you need to supply @handler and @thread_fn. @handler is
1639 * still called in hard interrupt context and has to check
1640 * whether the interrupt originates from the device. If yes it
1641 * needs to disable the interrupt on the device and return
1642 * IRQ_WAKE_THREAD which will wake up the handler thread and run
1643 * @thread_fn. This split handler design is necessary to support
1644 * shared interrupts.
1646 * Dev_id must be globally unique. Normally the address of the
1647 * device data structure is used as the cookie. Since the handler
1648 * receives this value it makes sense to use it.
1650 * If your interrupt is shared you must pass a non NULL dev_id
1651 * as this is required when freeing the interrupt.
1655 * IRQF_SHARED Interrupt is shared
1656 * IRQF_TRIGGER_* Specify active edge(s) or level
1659 int request_threaded_irq(unsigned int irq, irq_handler_t handler,
1660 irq_handler_t thread_fn, unsigned long irqflags,
1661 const char *devname, void *dev_id)
1663 struct irqaction *action;
1664 struct irq_desc *desc;
1667 if (irq == IRQ_NOTCONNECTED)
1671 * Sanity-check: shared interrupts must pass in a real dev-ID,
1672 * otherwise we'll have trouble later trying to figure out
1673 * which interrupt is which (messes up the interrupt freeing
1676 * Also IRQF_COND_SUSPEND only makes sense for shared interrupts and
1677 * it cannot be set along with IRQF_NO_SUSPEND.
1679 if (((irqflags & IRQF_SHARED) && !dev_id) ||
1680 (!(irqflags & IRQF_SHARED) && (irqflags & IRQF_COND_SUSPEND)) ||
1681 ((irqflags & IRQF_NO_SUSPEND) && (irqflags & IRQF_COND_SUSPEND)))
1684 desc = irq_to_desc(irq);
1688 if (!irq_settings_can_request(desc) ||
1689 WARN_ON(irq_settings_is_per_cpu_devid(desc)))
1695 handler = irq_default_primary_handler;
1698 action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
1702 action->handler = handler;
1703 action->thread_fn = thread_fn;
1704 action->flags = irqflags;
1705 action->name = devname;
1706 action->dev_id = dev_id;
1708 retval = irq_chip_pm_get(&desc->irq_data);
1714 chip_bus_lock(desc);
1715 retval = __setup_irq(irq, desc, action);
1716 chip_bus_sync_unlock(desc);
1719 irq_chip_pm_put(&desc->irq_data);
1720 kfree(action->secondary);
1724 #ifdef CONFIG_DEBUG_SHIRQ_FIXME
1725 if (!retval && (irqflags & IRQF_SHARED)) {
1727 * It's a shared IRQ -- the driver ought to be prepared for it
1728 * to happen immediately, so let's make sure....
1729 * We disable the irq to make sure that a 'real' IRQ doesn't
1730 * run in parallel with our fake.
1732 unsigned long flags;
1735 local_irq_save(flags);
1737 handler(irq, dev_id);
1739 local_irq_restore(flags);
1745 EXPORT_SYMBOL(request_threaded_irq);
1748 * request_any_context_irq - allocate an interrupt line
1749 * @irq: Interrupt line to allocate
1750 * @handler: Function to be called when the IRQ occurs.
1751 * Threaded handler for threaded interrupts.
1752 * @flags: Interrupt type flags
1753 * @name: An ascii name for the claiming device
1754 * @dev_id: A cookie passed back to the handler function
1756 * This call allocates interrupt resources and enables the
1757 * interrupt line and IRQ handling. It selects either a
1758 * hardirq or threaded handling method depending on the
1761 * On failure, it returns a negative value. On success,
1762 * it returns either IRQC_IS_HARDIRQ or IRQC_IS_NESTED.
1764 int request_any_context_irq(unsigned int irq, irq_handler_t handler,
1765 unsigned long flags, const char *name, void *dev_id)
1767 struct irq_desc *desc;
1770 if (irq == IRQ_NOTCONNECTED)
1773 desc = irq_to_desc(irq);
1777 if (irq_settings_is_nested_thread(desc)) {
1778 ret = request_threaded_irq(irq, NULL, handler,
1779 flags, name, dev_id);
1780 return !ret ? IRQC_IS_NESTED : ret;
1783 ret = request_irq(irq, handler, flags, name, dev_id);
1784 return !ret ? IRQC_IS_HARDIRQ : ret;
1786 EXPORT_SYMBOL_GPL(request_any_context_irq);
1788 void enable_percpu_irq(unsigned int irq, unsigned int type)
1790 unsigned int cpu = smp_processor_id();
1791 unsigned long flags;
1792 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);
1798 * If the trigger type is not specified by the caller, then
1799 * use the default for this interrupt.
1801 type &= IRQ_TYPE_SENSE_MASK;
1802 if (type == IRQ_TYPE_NONE)
1803 type = irqd_get_trigger_type(&desc->irq_data);
1805 if (type != IRQ_TYPE_NONE) {
1808 ret = __irq_set_trigger(desc, type);
1811 WARN(1, "failed to set type for IRQ%d\n", irq);
1816 irq_percpu_enable(desc, cpu);
1818 irq_put_desc_unlock(desc, flags);
1820 EXPORT_SYMBOL_GPL(enable_percpu_irq);
1823 * irq_percpu_is_enabled - Check whether the per cpu irq is enabled
1824 * @irq: Linux irq number to check for
1826 * Must be called from a non migratable context. Returns the enable
1827 * state of a per cpu interrupt on the current cpu.
1829 bool irq_percpu_is_enabled(unsigned int irq)
1831 unsigned int cpu = smp_processor_id();
1832 struct irq_desc *desc;
1833 unsigned long flags;
1836 desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);
1840 is_enabled = cpumask_test_cpu(cpu, desc->percpu_enabled);
1841 irq_put_desc_unlock(desc, flags);
1845 EXPORT_SYMBOL_GPL(irq_percpu_is_enabled);
1847 void disable_percpu_irq(unsigned int irq)
1849 unsigned int cpu = smp_processor_id();
1850 unsigned long flags;
1851 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);
1856 irq_percpu_disable(desc, cpu);
1857 irq_put_desc_unlock(desc, flags);
1859 EXPORT_SYMBOL_GPL(disable_percpu_irq);
1862 * Internal function to unregister a percpu irqaction.
1864 static struct irqaction *__free_percpu_irq(unsigned int irq, void __percpu *dev_id)
1866 struct irq_desc *desc = irq_to_desc(irq);
1867 struct irqaction *action;
1868 unsigned long flags;
1870 WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);
1875 raw_spin_lock_irqsave(&desc->lock, flags);
1877 action = desc->action;
1878 if (!action || action->percpu_dev_id != dev_id) {
1879 WARN(1, "Trying to free already-free IRQ %d\n", irq);
1883 if (!cpumask_empty(desc->percpu_enabled)) {
1884 WARN(1, "percpu IRQ %d still enabled on CPU%d!\n",
1885 irq, cpumask_first(desc->percpu_enabled));
1889 /* Found it - now remove it from the list of entries: */
1890 desc->action = NULL;
1892 raw_spin_unlock_irqrestore(&desc->lock, flags);
1894 unregister_handler_proc(irq, action);
1896 irq_chip_pm_put(&desc->irq_data);
1897 module_put(desc->owner);
1901 raw_spin_unlock_irqrestore(&desc->lock, flags);
1906 * remove_percpu_irq - free a per-cpu interrupt
1907 * @irq: Interrupt line to free
1908 * @act: irqaction for the interrupt
1910 * Used to remove interrupts statically setup by the early boot process.
1912 void remove_percpu_irq(unsigned int irq, struct irqaction *act)
1914 struct irq_desc *desc = irq_to_desc(irq);
1916 if (desc && irq_settings_is_per_cpu_devid(desc))
1917 __free_percpu_irq(irq, act->percpu_dev_id);
1921 * free_percpu_irq - free an interrupt allocated with request_percpu_irq
1922 * @irq: Interrupt line to free
1923 * @dev_id: Device identity to free
1925 * Remove a percpu interrupt handler. The handler is removed, but
1926 * the interrupt line is not disabled. This must be done on each
1927 * CPU before calling this function. The function does not return
1928 * until any executing interrupts for this IRQ have completed.
1930 * This function must not be called from interrupt context.
1932 void free_percpu_irq(unsigned int irq, void __percpu *dev_id)
1934 struct irq_desc *desc = irq_to_desc(irq);
1936 if (!desc || !irq_settings_is_per_cpu_devid(desc))
1939 chip_bus_lock(desc);
1940 kfree(__free_percpu_irq(irq, dev_id));
1941 chip_bus_sync_unlock(desc);
1943 EXPORT_SYMBOL_GPL(free_percpu_irq);
1946 * setup_percpu_irq - setup a per-cpu interrupt
1947 * @irq: Interrupt line to setup
1948 * @act: irqaction for the interrupt
1950 * Used to statically setup per-cpu interrupts in the early boot process.
1952 int setup_percpu_irq(unsigned int irq, struct irqaction *act)
1954 struct irq_desc *desc = irq_to_desc(irq);
1957 if (!desc || !irq_settings_is_per_cpu_devid(desc))
1960 retval = irq_chip_pm_get(&desc->irq_data);
1964 chip_bus_lock(desc);
1965 retval = __setup_irq(irq, desc, act);
1966 chip_bus_sync_unlock(desc);
1969 irq_chip_pm_put(&desc->irq_data);
1975 * request_percpu_irq - allocate a percpu interrupt line
1976 * @irq: Interrupt line to allocate
1977 * @handler: Function to be called when the IRQ occurs.
1978 * @devname: An ascii name for the claiming device
1979 * @dev_id: A percpu cookie passed back to the handler function
1981 * This call allocates interrupt resources and enables the
1982 * interrupt on the local CPU. If the interrupt is supposed to be
1983 * enabled on other CPUs, it has to be done on each CPU using
1984 * enable_percpu_irq().
1986 * Dev_id must be globally unique. It is a per-cpu variable, and
1987 * the handler gets called with the interrupted CPU's instance of
1990 int request_percpu_irq(unsigned int irq, irq_handler_t handler,
1991 const char *devname, void __percpu *dev_id)
1993 struct irqaction *action;
1994 struct irq_desc *desc;
2000 desc = irq_to_desc(irq);
2001 if (!desc || !irq_settings_can_request(desc) ||
2002 !irq_settings_is_per_cpu_devid(desc))
2005 action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
2009 action->handler = handler;
2010 action->flags = IRQF_PERCPU | IRQF_NO_SUSPEND;
2011 action->name = devname;
2012 action->percpu_dev_id = dev_id;
2014 retval = irq_chip_pm_get(&desc->irq_data);
2020 chip_bus_lock(desc);
2021 retval = __setup_irq(irq, desc, action);
2022 chip_bus_sync_unlock(desc);
2025 irq_chip_pm_put(&desc->irq_data);
2031 EXPORT_SYMBOL_GPL(request_percpu_irq);
2034 * irq_get_irqchip_state - returns the irqchip state of a interrupt.
2035 * @irq: Interrupt line that is forwarded to a VM
2036 * @which: One of IRQCHIP_STATE_* the caller wants to know about
2037 * @state: a pointer to a boolean where the state is to be storeed
2039 * This call snapshots the internal irqchip state of an
2040 * interrupt, returning into @state the bit corresponding to
2043 * This function should be called with preemption disabled if the
2044 * interrupt controller has per-cpu registers.
2046 int irq_get_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
2049 struct irq_desc *desc;
2050 struct irq_data *data;
2051 struct irq_chip *chip;
2052 unsigned long flags;
2055 desc = irq_get_desc_buslock(irq, &flags, 0);
2059 data = irq_desc_get_irq_data(desc);
2062 chip = irq_data_get_irq_chip(data);
2063 if (chip->irq_get_irqchip_state)
2065 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
2066 data = data->parent_data;
2073 err = chip->irq_get_irqchip_state(data, which, state);
2075 irq_put_desc_busunlock(desc, flags);
2078 EXPORT_SYMBOL_GPL(irq_get_irqchip_state);
2081 * irq_set_irqchip_state - set the state of a forwarded interrupt.
2082 * @irq: Interrupt line that is forwarded to a VM
2083 * @which: State to be restored (one of IRQCHIP_STATE_*)
2084 * @val: Value corresponding to @which
2086 * This call sets the internal irqchip state of an interrupt,
2087 * depending on the value of @which.
2089 * This function should be called with preemption disabled if the
2090 * interrupt controller has per-cpu registers.
2092 int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
2095 struct irq_desc *desc;
2096 struct irq_data *data;
2097 struct irq_chip *chip;
2098 unsigned long flags;
2101 desc = irq_get_desc_buslock(irq, &flags, 0);
2105 data = irq_desc_get_irq_data(desc);
2108 chip = irq_data_get_irq_chip(data);
2109 if (chip->irq_set_irqchip_state)
2111 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
2112 data = data->parent_data;
2119 err = chip->irq_set_irqchip_state(data, which, val);
2121 irq_put_desc_busunlock(desc, flags);
2124 EXPORT_SYMBOL_GPL(irq_set_irqchip_state);