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
);
1322 irq_release_resources(desc
);
1327 desc
->istate
&= ~(IRQS_AUTODETECT
| IRQS_SPURIOUS_DISABLED
| \
1328 IRQS_ONESHOT
| IRQS_WAITING
);
1329 irqd_clear(&desc
->irq_data
, IRQD_IRQ_INPROGRESS
);
1331 if (new->flags
& IRQF_PERCPU
) {
1332 irqd_set(&desc
->irq_data
, IRQD_PER_CPU
);
1333 irq_settings_set_per_cpu(desc
);
1336 if (new->flags
& IRQF_ONESHOT
)
1337 desc
->istate
|= IRQS_ONESHOT
;
1339 if (irq_settings_can_autoenable(desc
)) {
1340 irq_startup(desc
, true);
1343 * Shared interrupts do not go well with disabling
1344 * auto enable. The sharing interrupt might request
1345 * it while it's still disabled and then wait for
1346 * interrupts forever.
1348 WARN_ON_ONCE(new->flags
& IRQF_SHARED
);
1349 /* Undo nested disables: */
1353 /* Exclude IRQ from balancing if requested */
1354 if (new->flags
& IRQF_NOBALANCING
) {
1355 irq_settings_set_no_balancing(desc
);
1356 irqd_set(&desc
->irq_data
, IRQD_NO_BALANCING
);
1359 /* Set default affinity mask once everything is setup */
1360 setup_affinity(desc
, mask
);
1362 } else if (new->flags
& IRQF_TRIGGER_MASK
) {
1363 unsigned int nmsk
= new->flags
& IRQF_TRIGGER_MASK
;
1364 unsigned int omsk
= irqd_get_trigger_type(&desc
->irq_data
);
1367 /* hope the handler works with current trigger mode */
1368 pr_warn("irq %d uses trigger mode %u; requested %u\n",
1374 irq_pm_install_action(desc
, new);
1376 /* Reset broken irq detection when installing new handler */
1377 desc
->irq_count
= 0;
1378 desc
->irqs_unhandled
= 0;
1381 * Check whether we disabled the irq via the spurious handler
1382 * before. Reenable it and give it another chance.
1384 if (shared
&& (desc
->istate
& IRQS_SPURIOUS_DISABLED
)) {
1385 desc
->istate
&= ~IRQS_SPURIOUS_DISABLED
;
1389 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
1392 * Strictly no need to wake it up, but hung_task complains
1393 * when no hard interrupt wakes the thread up.
1396 wake_up_process(new->thread
);
1398 wake_up_process(new->secondary
->thread
);
1400 register_irq_proc(irq
, desc
);
1401 irq_add_debugfs_entry(irq
, desc
);
1403 register_handler_proc(irq
, new);
1404 free_cpumask_var(mask
);
1409 if (!(new->flags
& IRQF_PROBE_SHARED
)) {
1410 pr_err("Flags mismatch irq %d. %08x (%s) vs. %08x (%s)\n",
1411 irq
, new->flags
, new->name
, old
->flags
, old
->name
);
1412 #ifdef CONFIG_DEBUG_SHIRQ
1419 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
1420 free_cpumask_var(mask
);
1424 struct task_struct
*t
= new->thread
;
1430 if (new->secondary
&& new->secondary
->thread
) {
1431 struct task_struct
*t
= new->secondary
->thread
;
1433 new->secondary
->thread
= NULL
;
1438 module_put(desc
->owner
);
1443 * setup_irq - setup an interrupt
1444 * @irq: Interrupt line to setup
1445 * @act: irqaction for the interrupt
1447 * Used to statically setup interrupts in the early boot process.
1449 int setup_irq(unsigned int irq
, struct irqaction
*act
)
1452 struct irq_desc
*desc
= irq_to_desc(irq
);
1454 if (!desc
|| WARN_ON(irq_settings_is_per_cpu_devid(desc
)))
1457 retval
= irq_chip_pm_get(&desc
->irq_data
);
1461 chip_bus_lock(desc
);
1462 retval
= __setup_irq(irq
, desc
, act
);
1463 chip_bus_sync_unlock(desc
);
1466 irq_chip_pm_put(&desc
->irq_data
);
1470 EXPORT_SYMBOL_GPL(setup_irq
);
1473 * Internal function to unregister an irqaction - used to free
1474 * regular and special interrupts that are part of the architecture.
1476 static struct irqaction
*__free_irq(unsigned int irq
, void *dev_id
)
1478 struct irq_desc
*desc
= irq_to_desc(irq
);
1479 struct irqaction
*action
, **action_ptr
;
1480 unsigned long flags
;
1482 WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq
);
1487 chip_bus_lock(desc
);
1488 raw_spin_lock_irqsave(&desc
->lock
, flags
);
1491 * There can be multiple actions per IRQ descriptor, find the right
1492 * one based on the dev_id:
1494 action_ptr
= &desc
->action
;
1496 action
= *action_ptr
;
1499 WARN(1, "Trying to free already-free IRQ %d\n", irq
);
1500 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
1501 chip_bus_sync_unlock(desc
);
1505 if (action
->dev_id
== dev_id
)
1507 action_ptr
= &action
->next
;
1510 /* Found it - now remove it from the list of entries: */
1511 *action_ptr
= action
->next
;
1513 irq_pm_remove_action(desc
, action
);
1515 /* If this was the last handler, shut down the IRQ line: */
1516 if (!desc
->action
) {
1517 irq_settings_clr_disable_unlazy(desc
);
1519 irq_release_resources(desc
);
1523 /* make sure affinity_hint is cleaned up */
1524 if (WARN_ON_ONCE(desc
->affinity_hint
))
1525 desc
->affinity_hint
= NULL
;
1528 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
1529 chip_bus_sync_unlock(desc
);
1531 unregister_handler_proc(irq
, action
);
1533 /* Make sure it's not being used on another CPU: */
1534 synchronize_irq(irq
);
1536 #ifdef CONFIG_DEBUG_SHIRQ
1538 * It's a shared IRQ -- the driver ought to be prepared for an IRQ
1539 * event to happen even now it's being freed, so let's make sure that
1540 * is so by doing an extra call to the handler ....
1542 * ( We do this after actually deregistering it, to make sure that a
1543 * 'real' IRQ doesn't run in * parallel with our fake. )
1545 if (action
->flags
& IRQF_SHARED
) {
1546 local_irq_save(flags
);
1547 action
->handler(irq
, dev_id
);
1548 local_irq_restore(flags
);
1552 if (action
->thread
) {
1553 kthread_stop(action
->thread
);
1554 put_task_struct(action
->thread
);
1555 if (action
->secondary
&& action
->secondary
->thread
) {
1556 kthread_stop(action
->secondary
->thread
);
1557 put_task_struct(action
->secondary
->thread
);
1561 irq_chip_pm_put(&desc
->irq_data
);
1562 module_put(desc
->owner
);
1563 kfree(action
->secondary
);
1568 * remove_irq - free an interrupt
1569 * @irq: Interrupt line to free
1570 * @act: irqaction for the interrupt
1572 * Used to remove interrupts statically setup by the early boot process.
1574 void remove_irq(unsigned int irq
, struct irqaction
*act
)
1576 struct irq_desc
*desc
= irq_to_desc(irq
);
1578 if (desc
&& !WARN_ON(irq_settings_is_per_cpu_devid(desc
)))
1579 __free_irq(irq
, act
->dev_id
);
1581 EXPORT_SYMBOL_GPL(remove_irq
);
1584 * free_irq - free an interrupt allocated with request_irq
1585 * @irq: Interrupt line to free
1586 * @dev_id: Device identity to free
1588 * Remove an interrupt handler. The handler is removed and if the
1589 * interrupt line is no longer in use by any driver it is disabled.
1590 * On a shared IRQ the caller must ensure the interrupt is disabled
1591 * on the card it drives before calling this function. The function
1592 * does not return until any executing interrupts for this IRQ
1595 * This function must not be called from interrupt context.
1597 * Returns the devname argument passed to request_irq.
1599 const void *free_irq(unsigned int irq
, void *dev_id
)
1601 struct irq_desc
*desc
= irq_to_desc(irq
);
1602 struct irqaction
*action
;
1603 const char *devname
;
1605 if (!desc
|| WARN_ON(irq_settings_is_per_cpu_devid(desc
)))
1609 if (WARN_ON(desc
->affinity_notify
))
1610 desc
->affinity_notify
= NULL
;
1613 action
= __free_irq(irq
, dev_id
);
1614 devname
= action
->name
;
1618 EXPORT_SYMBOL(free_irq
);
1621 * request_threaded_irq - allocate an interrupt line
1622 * @irq: Interrupt line to allocate
1623 * @handler: Function to be called when the IRQ occurs.
1624 * Primary handler for threaded interrupts
1625 * If NULL and thread_fn != NULL the default
1626 * primary handler is installed
1627 * @thread_fn: Function called from the irq handler thread
1628 * If NULL, no irq thread is created
1629 * @irqflags: Interrupt type flags
1630 * @devname: An ascii name for the claiming device
1631 * @dev_id: A cookie passed back to the handler function
1633 * This call allocates interrupt resources and enables the
1634 * interrupt line and IRQ handling. From the point this
1635 * call is made your handler function may be invoked. Since
1636 * your handler function must clear any interrupt the board
1637 * raises, you must take care both to initialise your hardware
1638 * and to set up the interrupt handler in the right order.
1640 * If you want to set up a threaded irq handler for your device
1641 * then you need to supply @handler and @thread_fn. @handler is
1642 * still called in hard interrupt context and has to check
1643 * whether the interrupt originates from the device. If yes it
1644 * needs to disable the interrupt on the device and return
1645 * IRQ_WAKE_THREAD which will wake up the handler thread and run
1646 * @thread_fn. This split handler design is necessary to support
1647 * shared interrupts.
1649 * Dev_id must be globally unique. Normally the address of the
1650 * device data structure is used as the cookie. Since the handler
1651 * receives this value it makes sense to use it.
1653 * If your interrupt is shared you must pass a non NULL dev_id
1654 * as this is required when freeing the interrupt.
1658 * IRQF_SHARED Interrupt is shared
1659 * IRQF_TRIGGER_* Specify active edge(s) or level
1662 int request_threaded_irq(unsigned int irq
, irq_handler_t handler
,
1663 irq_handler_t thread_fn
, unsigned long irqflags
,
1664 const char *devname
, void *dev_id
)
1666 struct irqaction
*action
;
1667 struct irq_desc
*desc
;
1670 if (irq
== IRQ_NOTCONNECTED
)
1674 * Sanity-check: shared interrupts must pass in a real dev-ID,
1675 * otherwise we'll have trouble later trying to figure out
1676 * which interrupt is which (messes up the interrupt freeing
1679 * Also IRQF_COND_SUSPEND only makes sense for shared interrupts and
1680 * it cannot be set along with IRQF_NO_SUSPEND.
1682 if (((irqflags
& IRQF_SHARED
) && !dev_id
) ||
1683 (!(irqflags
& IRQF_SHARED
) && (irqflags
& IRQF_COND_SUSPEND
)) ||
1684 ((irqflags
& IRQF_NO_SUSPEND
) && (irqflags
& IRQF_COND_SUSPEND
)))
1687 desc
= irq_to_desc(irq
);
1691 if (!irq_settings_can_request(desc
) ||
1692 WARN_ON(irq_settings_is_per_cpu_devid(desc
)))
1698 handler
= irq_default_primary_handler
;
1701 action
= kzalloc(sizeof(struct irqaction
), GFP_KERNEL
);
1705 action
->handler
= handler
;
1706 action
->thread_fn
= thread_fn
;
1707 action
->flags
= irqflags
;
1708 action
->name
= devname
;
1709 action
->dev_id
= dev_id
;
1711 retval
= irq_chip_pm_get(&desc
->irq_data
);
1717 chip_bus_lock(desc
);
1718 retval
= __setup_irq(irq
, desc
, action
);
1719 chip_bus_sync_unlock(desc
);
1722 irq_chip_pm_put(&desc
->irq_data
);
1723 kfree(action
->secondary
);
1727 #ifdef CONFIG_DEBUG_SHIRQ_FIXME
1728 if (!retval
&& (irqflags
& IRQF_SHARED
)) {
1730 * It's a shared IRQ -- the driver ought to be prepared for it
1731 * to happen immediately, so let's make sure....
1732 * We disable the irq to make sure that a 'real' IRQ doesn't
1733 * run in parallel with our fake.
1735 unsigned long flags
;
1738 local_irq_save(flags
);
1740 handler(irq
, dev_id
);
1742 local_irq_restore(flags
);
1748 EXPORT_SYMBOL(request_threaded_irq
);
1751 * request_any_context_irq - allocate an interrupt line
1752 * @irq: Interrupt line to allocate
1753 * @handler: Function to be called when the IRQ occurs.
1754 * Threaded handler for threaded interrupts.
1755 * @flags: Interrupt type flags
1756 * @name: An ascii name for the claiming device
1757 * @dev_id: A cookie passed back to the handler function
1759 * This call allocates interrupt resources and enables the
1760 * interrupt line and IRQ handling. It selects either a
1761 * hardirq or threaded handling method depending on the
1764 * On failure, it returns a negative value. On success,
1765 * it returns either IRQC_IS_HARDIRQ or IRQC_IS_NESTED.
1767 int request_any_context_irq(unsigned int irq
, irq_handler_t handler
,
1768 unsigned long flags
, const char *name
, void *dev_id
)
1770 struct irq_desc
*desc
;
1773 if (irq
== IRQ_NOTCONNECTED
)
1776 desc
= irq_to_desc(irq
);
1780 if (irq_settings_is_nested_thread(desc
)) {
1781 ret
= request_threaded_irq(irq
, NULL
, handler
,
1782 flags
, name
, dev_id
);
1783 return !ret
? IRQC_IS_NESTED
: ret
;
1786 ret
= request_irq(irq
, handler
, flags
, name
, dev_id
);
1787 return !ret
? IRQC_IS_HARDIRQ
: ret
;
1789 EXPORT_SYMBOL_GPL(request_any_context_irq
);
1791 void enable_percpu_irq(unsigned int irq
, unsigned int type
)
1793 unsigned int cpu
= smp_processor_id();
1794 unsigned long flags
;
1795 struct irq_desc
*desc
= irq_get_desc_lock(irq
, &flags
, IRQ_GET_DESC_CHECK_PERCPU
);
1801 * If the trigger type is not specified by the caller, then
1802 * use the default for this interrupt.
1804 type
&= IRQ_TYPE_SENSE_MASK
;
1805 if (type
== IRQ_TYPE_NONE
)
1806 type
= irqd_get_trigger_type(&desc
->irq_data
);
1808 if (type
!= IRQ_TYPE_NONE
) {
1811 ret
= __irq_set_trigger(desc
, type
);
1814 WARN(1, "failed to set type for IRQ%d\n", irq
);
1819 irq_percpu_enable(desc
, cpu
);
1821 irq_put_desc_unlock(desc
, flags
);
1823 EXPORT_SYMBOL_GPL(enable_percpu_irq
);
1826 * irq_percpu_is_enabled - Check whether the per cpu irq is enabled
1827 * @irq: Linux irq number to check for
1829 * Must be called from a non migratable context. Returns the enable
1830 * state of a per cpu interrupt on the current cpu.
1832 bool irq_percpu_is_enabled(unsigned int irq
)
1834 unsigned int cpu
= smp_processor_id();
1835 struct irq_desc
*desc
;
1836 unsigned long flags
;
1839 desc
= irq_get_desc_lock(irq
, &flags
, IRQ_GET_DESC_CHECK_PERCPU
);
1843 is_enabled
= cpumask_test_cpu(cpu
, desc
->percpu_enabled
);
1844 irq_put_desc_unlock(desc
, flags
);
1848 EXPORT_SYMBOL_GPL(irq_percpu_is_enabled
);
1850 void disable_percpu_irq(unsigned int irq
)
1852 unsigned int cpu
= smp_processor_id();
1853 unsigned long flags
;
1854 struct irq_desc
*desc
= irq_get_desc_lock(irq
, &flags
, IRQ_GET_DESC_CHECK_PERCPU
);
1859 irq_percpu_disable(desc
, cpu
);
1860 irq_put_desc_unlock(desc
, flags
);
1862 EXPORT_SYMBOL_GPL(disable_percpu_irq
);
1865 * Internal function to unregister a percpu irqaction.
1867 static struct irqaction
*__free_percpu_irq(unsigned int irq
, void __percpu
*dev_id
)
1869 struct irq_desc
*desc
= irq_to_desc(irq
);
1870 struct irqaction
*action
;
1871 unsigned long flags
;
1873 WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq
);
1878 raw_spin_lock_irqsave(&desc
->lock
, flags
);
1880 action
= desc
->action
;
1881 if (!action
|| action
->percpu_dev_id
!= dev_id
) {
1882 WARN(1, "Trying to free already-free IRQ %d\n", irq
);
1886 if (!cpumask_empty(desc
->percpu_enabled
)) {
1887 WARN(1, "percpu IRQ %d still enabled on CPU%d!\n",
1888 irq
, cpumask_first(desc
->percpu_enabled
));
1892 /* Found it - now remove it from the list of entries: */
1893 desc
->action
= NULL
;
1895 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
1897 unregister_handler_proc(irq
, action
);
1899 irq_chip_pm_put(&desc
->irq_data
);
1900 module_put(desc
->owner
);
1904 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
1909 * remove_percpu_irq - free a per-cpu interrupt
1910 * @irq: Interrupt line to free
1911 * @act: irqaction for the interrupt
1913 * Used to remove interrupts statically setup by the early boot process.
1915 void remove_percpu_irq(unsigned int irq
, struct irqaction
*act
)
1917 struct irq_desc
*desc
= irq_to_desc(irq
);
1919 if (desc
&& irq_settings_is_per_cpu_devid(desc
))
1920 __free_percpu_irq(irq
, act
->percpu_dev_id
);
1924 * free_percpu_irq - free an interrupt allocated with request_percpu_irq
1925 * @irq: Interrupt line to free
1926 * @dev_id: Device identity to free
1928 * Remove a percpu interrupt handler. The handler is removed, but
1929 * the interrupt line is not disabled. This must be done on each
1930 * CPU before calling this function. The function does not return
1931 * until any executing interrupts for this IRQ have completed.
1933 * This function must not be called from interrupt context.
1935 void free_percpu_irq(unsigned int irq
, void __percpu
*dev_id
)
1937 struct irq_desc
*desc
= irq_to_desc(irq
);
1939 if (!desc
|| !irq_settings_is_per_cpu_devid(desc
))
1942 chip_bus_lock(desc
);
1943 kfree(__free_percpu_irq(irq
, dev_id
));
1944 chip_bus_sync_unlock(desc
);
1946 EXPORT_SYMBOL_GPL(free_percpu_irq
);
1949 * setup_percpu_irq - setup a per-cpu interrupt
1950 * @irq: Interrupt line to setup
1951 * @act: irqaction for the interrupt
1953 * Used to statically setup per-cpu interrupts in the early boot process.
1955 int setup_percpu_irq(unsigned int irq
, struct irqaction
*act
)
1957 struct irq_desc
*desc
= irq_to_desc(irq
);
1960 if (!desc
|| !irq_settings_is_per_cpu_devid(desc
))
1963 retval
= irq_chip_pm_get(&desc
->irq_data
);
1967 chip_bus_lock(desc
);
1968 retval
= __setup_irq(irq
, desc
, act
);
1969 chip_bus_sync_unlock(desc
);
1972 irq_chip_pm_put(&desc
->irq_data
);
1978 * request_percpu_irq - allocate a percpu interrupt line
1979 * @irq: Interrupt line to allocate
1980 * @handler: Function to be called when the IRQ occurs.
1981 * @devname: An ascii name for the claiming device
1982 * @dev_id: A percpu cookie passed back to the handler function
1984 * This call allocates interrupt resources and enables the
1985 * interrupt on the local CPU. If the interrupt is supposed to be
1986 * enabled on other CPUs, it has to be done on each CPU using
1987 * enable_percpu_irq().
1989 * Dev_id must be globally unique. It is a per-cpu variable, and
1990 * the handler gets called with the interrupted CPU's instance of
1993 int request_percpu_irq(unsigned int irq
, irq_handler_t handler
,
1994 const char *devname
, void __percpu
*dev_id
)
1996 struct irqaction
*action
;
1997 struct irq_desc
*desc
;
2003 desc
= irq_to_desc(irq
);
2004 if (!desc
|| !irq_settings_can_request(desc
) ||
2005 !irq_settings_is_per_cpu_devid(desc
))
2008 action
= kzalloc(sizeof(struct irqaction
), GFP_KERNEL
);
2012 action
->handler
= handler
;
2013 action
->flags
= IRQF_PERCPU
| IRQF_NO_SUSPEND
;
2014 action
->name
= devname
;
2015 action
->percpu_dev_id
= dev_id
;
2017 retval
= irq_chip_pm_get(&desc
->irq_data
);
2023 chip_bus_lock(desc
);
2024 retval
= __setup_irq(irq
, desc
, action
);
2025 chip_bus_sync_unlock(desc
);
2028 irq_chip_pm_put(&desc
->irq_data
);
2034 EXPORT_SYMBOL_GPL(request_percpu_irq
);
2037 * irq_get_irqchip_state - returns the irqchip state of a interrupt.
2038 * @irq: Interrupt line that is forwarded to a VM
2039 * @which: One of IRQCHIP_STATE_* the caller wants to know about
2040 * @state: a pointer to a boolean where the state is to be storeed
2042 * This call snapshots the internal irqchip state of an
2043 * interrupt, returning into @state the bit corresponding to
2046 * This function should be called with preemption disabled if the
2047 * interrupt controller has per-cpu registers.
2049 int irq_get_irqchip_state(unsigned int irq
, enum irqchip_irq_state which
,
2052 struct irq_desc
*desc
;
2053 struct irq_data
*data
;
2054 struct irq_chip
*chip
;
2055 unsigned long flags
;
2058 desc
= irq_get_desc_buslock(irq
, &flags
, 0);
2062 data
= irq_desc_get_irq_data(desc
);
2065 chip
= irq_data_get_irq_chip(data
);
2066 if (chip
->irq_get_irqchip_state
)
2068 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
2069 data
= data
->parent_data
;
2076 err
= chip
->irq_get_irqchip_state(data
, which
, state
);
2078 irq_put_desc_busunlock(desc
, flags
);
2081 EXPORT_SYMBOL_GPL(irq_get_irqchip_state
);
2084 * irq_set_irqchip_state - set the state of a forwarded interrupt.
2085 * @irq: Interrupt line that is forwarded to a VM
2086 * @which: State to be restored (one of IRQCHIP_STATE_*)
2087 * @val: Value corresponding to @which
2089 * This call sets the internal irqchip state of an interrupt,
2090 * depending on the value of @which.
2092 * This function should be called with preemption disabled if the
2093 * interrupt controller has per-cpu registers.
2095 int irq_set_irqchip_state(unsigned int irq
, enum irqchip_irq_state which
,
2098 struct irq_desc
*desc
;
2099 struct irq_data
*data
;
2100 struct irq_chip
*chip
;
2101 unsigned long flags
;
2104 desc
= irq_get_desc_buslock(irq
, &flags
, 0);
2108 data
= irq_desc_get_irq_data(desc
);
2111 chip
= irq_data_get_irq_chip(data
);
2112 if (chip
->irq_set_irqchip_state
)
2114 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
2115 data
= data
->parent_data
;
2122 err
= chip
->irq_set_irqchip_state(data
, which
, val
);
2124 irq_put_desc_busunlock(desc
, flags
);
2127 EXPORT_SYMBOL_GPL(irq_set_irqchip_state
);