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/task_work.h>
22 #include "internals.h"
24 #ifdef CONFIG_IRQ_FORCED_THREADING
25 __read_mostly
bool force_irqthreads
;
27 static int __init
setup_forced_irqthreads(char *arg
)
29 force_irqthreads
= true;
32 early_param("threadirqs", setup_forced_irqthreads
);
35 static void __synchronize_hardirq(struct irq_desc
*desc
)
43 * Wait until we're out of the critical section. This might
44 * give the wrong answer due to the lack of memory barriers.
46 while (irqd_irq_inprogress(&desc
->irq_data
))
49 /* Ok, that indicated we're done: double-check carefully. */
50 raw_spin_lock_irqsave(&desc
->lock
, flags
);
51 inprogress
= irqd_irq_inprogress(&desc
->irq_data
);
52 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
54 /* Oops, that failed? */
59 * synchronize_hardirq - wait for pending hard IRQ handlers (on other CPUs)
60 * @irq: interrupt number to wait for
62 * This function waits for any pending hard IRQ handlers for this
63 * interrupt to complete before returning. If you use this
64 * function while holding a resource the IRQ handler may need you
65 * will deadlock. It does not take associated threaded handlers
68 * Do not use this for shutdown scenarios where you must be sure
69 * that all parts (hardirq and threaded handler) have completed.
71 * Returns: false if a threaded handler is active.
73 * This function may be called - with care - from IRQ context.
75 bool synchronize_hardirq(unsigned int irq
)
77 struct irq_desc
*desc
= irq_to_desc(irq
);
80 __synchronize_hardirq(desc
);
81 return !atomic_read(&desc
->threads_active
);
86 EXPORT_SYMBOL(synchronize_hardirq
);
89 * synchronize_irq - wait for pending IRQ handlers (on other CPUs)
90 * @irq: interrupt number to wait for
92 * This function waits for any pending IRQ handlers for this interrupt
93 * to complete before returning. If you use this function while
94 * holding a resource the IRQ handler may need you will deadlock.
96 * This function may be called - with care - from IRQ context.
98 void synchronize_irq(unsigned int irq
)
100 struct irq_desc
*desc
= irq_to_desc(irq
);
103 __synchronize_hardirq(desc
);
105 * We made sure that no hardirq handler is
106 * running. Now verify that no threaded handlers are
109 wait_event(desc
->wait_for_threads
,
110 !atomic_read(&desc
->threads_active
));
113 EXPORT_SYMBOL(synchronize_irq
);
116 cpumask_var_t irq_default_affinity
;
118 static bool __irq_can_set_affinity(struct irq_desc
*desc
)
120 if (!desc
|| !irqd_can_balance(&desc
->irq_data
) ||
121 !desc
->irq_data
.chip
|| !desc
->irq_data
.chip
->irq_set_affinity
)
127 * irq_can_set_affinity - Check if the affinity of a given irq can be set
128 * @irq: Interrupt to check
131 int irq_can_set_affinity(unsigned int irq
)
133 return __irq_can_set_affinity(irq_to_desc(irq
));
137 * irq_can_set_affinity_usr - Check if affinity of a irq can be set from user space
138 * @irq: Interrupt to check
140 * Like irq_can_set_affinity() above, but additionally checks for the
141 * AFFINITY_MANAGED flag.
143 bool irq_can_set_affinity_usr(unsigned int irq
)
145 struct irq_desc
*desc
= irq_to_desc(irq
);
147 return __irq_can_set_affinity(desc
) &&
148 !irqd_affinity_is_managed(&desc
->irq_data
);
152 * irq_set_thread_affinity - Notify irq threads to adjust affinity
153 * @desc: irq descriptor which has affitnity changed
155 * We just set IRQTF_AFFINITY and delegate the affinity setting
156 * to the interrupt thread itself. We can not call
157 * set_cpus_allowed_ptr() here as we hold desc->lock and this
158 * code can be called from hard interrupt context.
160 void irq_set_thread_affinity(struct irq_desc
*desc
)
162 struct irqaction
*action
;
164 for_each_action_of_desc(desc
, action
)
166 set_bit(IRQTF_AFFINITY
, &action
->thread_flags
);
169 #ifdef CONFIG_GENERIC_PENDING_IRQ
170 static inline bool irq_can_move_pcntxt(struct irq_data
*data
)
172 return irqd_can_move_in_process_context(data
);
174 static inline bool irq_move_pending(struct irq_data
*data
)
176 return irqd_is_setaffinity_pending(data
);
179 irq_copy_pending(struct irq_desc
*desc
, const struct cpumask
*mask
)
181 cpumask_copy(desc
->pending_mask
, mask
);
184 irq_get_pending(struct cpumask
*mask
, struct irq_desc
*desc
)
186 cpumask_copy(mask
, desc
->pending_mask
);
189 static inline bool irq_can_move_pcntxt(struct irq_data
*data
) { return true; }
190 static inline bool irq_move_pending(struct irq_data
*data
) { return false; }
192 irq_copy_pending(struct irq_desc
*desc
, const struct cpumask
*mask
) { }
194 irq_get_pending(struct cpumask
*mask
, struct irq_desc
*desc
) { }
197 int irq_do_set_affinity(struct irq_data
*data
, const struct cpumask
*mask
,
200 struct irq_desc
*desc
= irq_data_to_desc(data
);
201 struct irq_chip
*chip
= irq_data_get_irq_chip(data
);
204 ret
= chip
->irq_set_affinity(data
, mask
, force
);
206 case IRQ_SET_MASK_OK
:
207 case IRQ_SET_MASK_OK_DONE
:
208 cpumask_copy(desc
->irq_common_data
.affinity
, mask
);
209 case IRQ_SET_MASK_OK_NOCOPY
:
210 irq_set_thread_affinity(desc
);
217 int irq_set_affinity_locked(struct irq_data
*data
, const struct cpumask
*mask
,
220 struct irq_chip
*chip
= irq_data_get_irq_chip(data
);
221 struct irq_desc
*desc
= irq_data_to_desc(data
);
224 if (!chip
|| !chip
->irq_set_affinity
)
227 if (irq_can_move_pcntxt(data
)) {
228 ret
= irq_do_set_affinity(data
, mask
, force
);
230 irqd_set_move_pending(data
);
231 irq_copy_pending(desc
, mask
);
234 if (desc
->affinity_notify
) {
235 kref_get(&desc
->affinity_notify
->kref
);
236 schedule_work(&desc
->affinity_notify
->work
);
238 irqd_set(data
, IRQD_AFFINITY_SET
);
243 int __irq_set_affinity(unsigned int irq
, const struct cpumask
*mask
, bool force
)
245 struct irq_desc
*desc
= irq_to_desc(irq
);
252 raw_spin_lock_irqsave(&desc
->lock
, flags
);
253 ret
= irq_set_affinity_locked(irq_desc_get_irq_data(desc
), mask
, force
);
254 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
258 int irq_set_affinity_hint(unsigned int irq
, const struct cpumask
*m
)
261 struct irq_desc
*desc
= irq_get_desc_lock(irq
, &flags
, IRQ_GET_DESC_CHECK_GLOBAL
);
265 desc
->affinity_hint
= m
;
266 irq_put_desc_unlock(desc
, flags
);
267 /* set the initial affinity to prevent every interrupt being on CPU0 */
269 __irq_set_affinity(irq
, m
, false);
272 EXPORT_SYMBOL_GPL(irq_set_affinity_hint
);
274 static void irq_affinity_notify(struct work_struct
*work
)
276 struct irq_affinity_notify
*notify
=
277 container_of(work
, struct irq_affinity_notify
, work
);
278 struct irq_desc
*desc
= irq_to_desc(notify
->irq
);
279 cpumask_var_t cpumask
;
282 if (!desc
|| !alloc_cpumask_var(&cpumask
, GFP_KERNEL
))
285 raw_spin_lock_irqsave(&desc
->lock
, flags
);
286 if (irq_move_pending(&desc
->irq_data
))
287 irq_get_pending(cpumask
, desc
);
289 cpumask_copy(cpumask
, desc
->irq_common_data
.affinity
);
290 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
292 notify
->notify(notify
, cpumask
);
294 free_cpumask_var(cpumask
);
296 kref_put(¬ify
->kref
, notify
->release
);
300 * irq_set_affinity_notifier - control notification of IRQ affinity changes
301 * @irq: Interrupt for which to enable/disable notification
302 * @notify: Context for notification, or %NULL to disable
303 * notification. Function pointers must be initialised;
304 * the other fields will be initialised by this function.
306 * Must be called in process context. Notification may only be enabled
307 * after the IRQ is allocated and must be disabled before the IRQ is
308 * freed using free_irq().
311 irq_set_affinity_notifier(unsigned int irq
, struct irq_affinity_notify
*notify
)
313 struct irq_desc
*desc
= irq_to_desc(irq
);
314 struct irq_affinity_notify
*old_notify
;
317 /* The release function is promised process context */
323 /* Complete initialisation of *notify */
326 kref_init(¬ify
->kref
);
327 INIT_WORK(¬ify
->work
, irq_affinity_notify
);
330 raw_spin_lock_irqsave(&desc
->lock
, flags
);
331 old_notify
= desc
->affinity_notify
;
332 desc
->affinity_notify
= notify
;
333 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
336 kref_put(&old_notify
->kref
, old_notify
->release
);
340 EXPORT_SYMBOL_GPL(irq_set_affinity_notifier
);
342 #ifndef CONFIG_AUTO_IRQ_AFFINITY
344 * Generic version of the affinity autoselector.
346 static int setup_affinity(struct irq_desc
*desc
, struct cpumask
*mask
)
348 struct cpumask
*set
= irq_default_affinity
;
349 int node
= irq_desc_get_node(desc
);
351 /* Excludes PER_CPU and NO_BALANCE interrupts */
352 if (!__irq_can_set_affinity(desc
))
356 * Preserve the managed affinity setting and an userspace affinity
357 * setup, but make sure that one of the targets is online.
359 if (irqd_affinity_is_managed(&desc
->irq_data
) ||
360 irqd_has_set(&desc
->irq_data
, IRQD_AFFINITY_SET
)) {
361 if (cpumask_intersects(desc
->irq_common_data
.affinity
,
363 set
= desc
->irq_common_data
.affinity
;
365 irqd_clear(&desc
->irq_data
, IRQD_AFFINITY_SET
);
368 cpumask_and(mask
, cpu_online_mask
, set
);
369 if (node
!= NUMA_NO_NODE
) {
370 const struct cpumask
*nodemask
= cpumask_of_node(node
);
372 /* make sure at least one of the cpus in nodemask is online */
373 if (cpumask_intersects(mask
, nodemask
))
374 cpumask_and(mask
, mask
, nodemask
);
376 irq_do_set_affinity(&desc
->irq_data
, mask
, false);
380 /* Wrapper for ALPHA specific affinity selector magic */
381 static inline int setup_affinity(struct irq_desc
*d
, struct cpumask
*mask
)
383 return irq_select_affinity(irq_desc_get_irq(d
));
388 * Called when affinity is set via /proc/irq
390 int irq_select_affinity_usr(unsigned int irq
, struct cpumask
*mask
)
392 struct irq_desc
*desc
= irq_to_desc(irq
);
396 raw_spin_lock_irqsave(&desc
->lock
, flags
);
397 ret
= setup_affinity(desc
, mask
);
398 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
404 setup_affinity(struct irq_desc
*desc
, struct cpumask
*mask
)
411 * irq_set_vcpu_affinity - Set vcpu affinity for the interrupt
412 * @irq: interrupt number to set affinity
413 * @vcpu_info: vCPU specific data
415 * This function uses the vCPU specific data to set the vCPU
416 * affinity for an irq. The vCPU specific data is passed from
417 * outside, such as KVM. One example code path is as below:
418 * KVM -> IOMMU -> irq_set_vcpu_affinity().
420 int irq_set_vcpu_affinity(unsigned int irq
, void *vcpu_info
)
423 struct irq_desc
*desc
= irq_get_desc_lock(irq
, &flags
, 0);
424 struct irq_data
*data
;
425 struct irq_chip
*chip
;
431 data
= irq_desc_get_irq_data(desc
);
432 chip
= irq_data_get_irq_chip(data
);
433 if (chip
&& chip
->irq_set_vcpu_affinity
)
434 ret
= chip
->irq_set_vcpu_affinity(data
, vcpu_info
);
435 irq_put_desc_unlock(desc
, flags
);
439 EXPORT_SYMBOL_GPL(irq_set_vcpu_affinity
);
441 void __disable_irq(struct irq_desc
*desc
)
447 static int __disable_irq_nosync(unsigned int irq
)
450 struct irq_desc
*desc
= irq_get_desc_buslock(irq
, &flags
, IRQ_GET_DESC_CHECK_GLOBAL
);
455 irq_put_desc_busunlock(desc
, flags
);
460 * disable_irq_nosync - disable an irq without waiting
461 * @irq: Interrupt to disable
463 * Disable the selected interrupt line. Disables and Enables are
465 * Unlike disable_irq(), this function does not ensure existing
466 * instances of the IRQ handler have completed before returning.
468 * This function may be called from IRQ context.
470 void disable_irq_nosync(unsigned int irq
)
472 __disable_irq_nosync(irq
);
474 EXPORT_SYMBOL(disable_irq_nosync
);
477 * disable_irq - disable an irq and wait for completion
478 * @irq: Interrupt to disable
480 * Disable the selected interrupt line. Enables and Disables are
482 * This function waits for any pending IRQ handlers for this interrupt
483 * to complete before returning. If you use this function while
484 * holding a resource the IRQ handler may need you will deadlock.
486 * This function may be called - with care - from IRQ context.
488 void disable_irq(unsigned int irq
)
490 if (!__disable_irq_nosync(irq
))
491 synchronize_irq(irq
);
493 EXPORT_SYMBOL(disable_irq
);
496 * disable_hardirq - disables an irq and waits for hardirq completion
497 * @irq: Interrupt to disable
499 * Disable the selected interrupt line. Enables and Disables are
501 * This function waits for any pending hard IRQ handlers for this
502 * interrupt to complete before returning. If you use this function while
503 * holding a resource the hard IRQ handler may need you will deadlock.
505 * When used to optimistically disable an interrupt from atomic context
506 * the return value must be checked.
508 * Returns: false if a threaded handler is active.
510 * This function may be called - with care - from IRQ context.
512 bool disable_hardirq(unsigned int irq
)
514 if (!__disable_irq_nosync(irq
))
515 return synchronize_hardirq(irq
);
519 EXPORT_SYMBOL_GPL(disable_hardirq
);
521 void __enable_irq(struct irq_desc
*desc
)
523 switch (desc
->depth
) {
526 WARN(1, KERN_WARNING
"Unbalanced enable for IRQ %d\n",
527 irq_desc_get_irq(desc
));
530 if (desc
->istate
& IRQS_SUSPENDED
)
532 /* Prevent probing on this irq: */
533 irq_settings_set_noprobe(desc
);
535 check_irq_resend(desc
);
544 * enable_irq - enable handling of an irq
545 * @irq: Interrupt to enable
547 * Undoes the effect of one call to disable_irq(). If this
548 * matches the last disable, processing of interrupts on this
549 * IRQ line is re-enabled.
551 * This function may be called from IRQ context only when
552 * desc->irq_data.chip->bus_lock and desc->chip->bus_sync_unlock are NULL !
554 void enable_irq(unsigned int irq
)
557 struct irq_desc
*desc
= irq_get_desc_buslock(irq
, &flags
, IRQ_GET_DESC_CHECK_GLOBAL
);
561 if (WARN(!desc
->irq_data
.chip
,
562 KERN_ERR
"enable_irq before setup/request_irq: irq %u\n", irq
))
567 irq_put_desc_busunlock(desc
, flags
);
569 EXPORT_SYMBOL(enable_irq
);
571 static int set_irq_wake_real(unsigned int irq
, unsigned int on
)
573 struct irq_desc
*desc
= irq_to_desc(irq
);
576 if (irq_desc_get_chip(desc
)->flags
& IRQCHIP_SKIP_SET_WAKE
)
579 if (desc
->irq_data
.chip
->irq_set_wake
)
580 ret
= desc
->irq_data
.chip
->irq_set_wake(&desc
->irq_data
, on
);
586 * irq_set_irq_wake - control irq power management wakeup
587 * @irq: interrupt to control
588 * @on: enable/disable power management wakeup
590 * Enable/disable power management wakeup mode, which is
591 * disabled by default. Enables and disables must match,
592 * just as they match for non-wakeup mode support.
594 * Wakeup mode lets this IRQ wake the system from sleep
595 * states like "suspend to RAM".
597 int irq_set_irq_wake(unsigned int irq
, unsigned int on
)
600 struct irq_desc
*desc
= irq_get_desc_buslock(irq
, &flags
, IRQ_GET_DESC_CHECK_GLOBAL
);
606 /* wakeup-capable irqs can be shared between drivers that
607 * don't need to have the same sleep mode behaviors.
610 if (desc
->wake_depth
++ == 0) {
611 ret
= set_irq_wake_real(irq
, on
);
613 desc
->wake_depth
= 0;
615 irqd_set(&desc
->irq_data
, IRQD_WAKEUP_STATE
);
618 if (desc
->wake_depth
== 0) {
619 WARN(1, "Unbalanced IRQ %d wake disable\n", irq
);
620 } else if (--desc
->wake_depth
== 0) {
621 ret
= set_irq_wake_real(irq
, on
);
623 desc
->wake_depth
= 1;
625 irqd_clear(&desc
->irq_data
, IRQD_WAKEUP_STATE
);
628 irq_put_desc_busunlock(desc
, flags
);
631 EXPORT_SYMBOL(irq_set_irq_wake
);
634 * Internal function that tells the architecture code whether a
635 * particular irq has been exclusively allocated or is available
638 int can_request_irq(unsigned int irq
, unsigned long irqflags
)
641 struct irq_desc
*desc
= irq_get_desc_lock(irq
, &flags
, 0);
647 if (irq_settings_can_request(desc
)) {
649 irqflags
& desc
->action
->flags
& IRQF_SHARED
)
652 irq_put_desc_unlock(desc
, flags
);
656 int __irq_set_trigger(struct irq_desc
*desc
, unsigned long flags
)
658 struct irq_chip
*chip
= desc
->irq_data
.chip
;
661 if (!chip
|| !chip
->irq_set_type
) {
663 * IRQF_TRIGGER_* but the PIC does not support multiple
666 pr_debug("No set_type function for IRQ %d (%s)\n",
667 irq_desc_get_irq(desc
),
668 chip
? (chip
->name
? : "unknown") : "unknown");
672 if (chip
->flags
& IRQCHIP_SET_TYPE_MASKED
) {
673 if (!irqd_irq_masked(&desc
->irq_data
))
675 if (!irqd_irq_disabled(&desc
->irq_data
))
679 /* Mask all flags except trigger mode */
680 flags
&= IRQ_TYPE_SENSE_MASK
;
681 ret
= chip
->irq_set_type(&desc
->irq_data
, flags
);
684 case IRQ_SET_MASK_OK
:
685 case IRQ_SET_MASK_OK_DONE
:
686 irqd_clear(&desc
->irq_data
, IRQD_TRIGGER_MASK
);
687 irqd_set(&desc
->irq_data
, flags
);
689 case IRQ_SET_MASK_OK_NOCOPY
:
690 flags
= irqd_get_trigger_type(&desc
->irq_data
);
691 irq_settings_set_trigger_mask(desc
, flags
);
692 irqd_clear(&desc
->irq_data
, IRQD_LEVEL
);
693 irq_settings_clr_level(desc
);
694 if (flags
& IRQ_TYPE_LEVEL_MASK
) {
695 irq_settings_set_level(desc
);
696 irqd_set(&desc
->irq_data
, IRQD_LEVEL
);
702 pr_err("Setting trigger mode %lu for irq %u failed (%pF)\n",
703 flags
, irq_desc_get_irq(desc
), chip
->irq_set_type
);
710 #ifdef CONFIG_HARDIRQS_SW_RESEND
711 int irq_set_parent(int irq
, int parent_irq
)
714 struct irq_desc
*desc
= irq_get_desc_lock(irq
, &flags
, 0);
719 desc
->parent_irq
= parent_irq
;
721 irq_put_desc_unlock(desc
, flags
);
727 * Default primary interrupt handler for threaded interrupts. Is
728 * assigned as primary handler when request_threaded_irq is called
729 * with handler == NULL. Useful for oneshot interrupts.
731 static irqreturn_t
irq_default_primary_handler(int irq
, void *dev_id
)
733 return IRQ_WAKE_THREAD
;
737 * Primary handler for nested threaded interrupts. Should never be
740 static irqreturn_t
irq_nested_primary_handler(int irq
, void *dev_id
)
742 WARN(1, "Primary handler called for nested irq %d\n", irq
);
746 static irqreturn_t
irq_forced_secondary_handler(int irq
, void *dev_id
)
748 WARN(1, "Secondary action handler called for irq %d\n", irq
);
752 static int irq_wait_for_interrupt(struct irqaction
*action
)
754 set_current_state(TASK_INTERRUPTIBLE
);
756 while (!kthread_should_stop()) {
758 if (test_and_clear_bit(IRQTF_RUNTHREAD
,
759 &action
->thread_flags
)) {
760 __set_current_state(TASK_RUNNING
);
764 set_current_state(TASK_INTERRUPTIBLE
);
766 __set_current_state(TASK_RUNNING
);
771 * Oneshot interrupts keep the irq line masked until the threaded
772 * handler finished. unmask if the interrupt has not been disabled and
775 static void irq_finalize_oneshot(struct irq_desc
*desc
,
776 struct irqaction
*action
)
778 if (!(desc
->istate
& IRQS_ONESHOT
) ||
779 action
->handler
== irq_forced_secondary_handler
)
783 raw_spin_lock_irq(&desc
->lock
);
786 * Implausible though it may be we need to protect us against
787 * the following scenario:
789 * The thread is faster done than the hard interrupt handler
790 * on the other CPU. If we unmask the irq line then the
791 * interrupt can come in again and masks the line, leaves due
792 * to IRQS_INPROGRESS and the irq line is masked forever.
794 * This also serializes the state of shared oneshot handlers
795 * versus "desc->threads_onehsot |= action->thread_mask;" in
796 * irq_wake_thread(). See the comment there which explains the
799 if (unlikely(irqd_irq_inprogress(&desc
->irq_data
))) {
800 raw_spin_unlock_irq(&desc
->lock
);
801 chip_bus_sync_unlock(desc
);
807 * Now check again, whether the thread should run. Otherwise
808 * we would clear the threads_oneshot bit of this thread which
811 if (test_bit(IRQTF_RUNTHREAD
, &action
->thread_flags
))
814 desc
->threads_oneshot
&= ~action
->thread_mask
;
816 if (!desc
->threads_oneshot
&& !irqd_irq_disabled(&desc
->irq_data
) &&
817 irqd_irq_masked(&desc
->irq_data
))
818 unmask_threaded_irq(desc
);
821 raw_spin_unlock_irq(&desc
->lock
);
822 chip_bus_sync_unlock(desc
);
827 * Check whether we need to change the affinity of the interrupt thread.
830 irq_thread_check_affinity(struct irq_desc
*desc
, struct irqaction
*action
)
835 if (!test_and_clear_bit(IRQTF_AFFINITY
, &action
->thread_flags
))
839 * In case we are out of memory we set IRQTF_AFFINITY again and
840 * try again next time
842 if (!alloc_cpumask_var(&mask
, GFP_KERNEL
)) {
843 set_bit(IRQTF_AFFINITY
, &action
->thread_flags
);
847 raw_spin_lock_irq(&desc
->lock
);
849 * This code is triggered unconditionally. Check the affinity
850 * mask pointer. For CPU_MASK_OFFSTACK=n this is optimized out.
852 if (desc
->irq_common_data
.affinity
)
853 cpumask_copy(mask
, desc
->irq_common_data
.affinity
);
856 raw_spin_unlock_irq(&desc
->lock
);
859 set_cpus_allowed_ptr(current
, mask
);
860 free_cpumask_var(mask
);
864 irq_thread_check_affinity(struct irq_desc
*desc
, struct irqaction
*action
) { }
868 * Interrupts which are not explicitely requested as threaded
869 * interrupts rely on the implicit bh/preempt disable of the hard irq
870 * context. So we need to disable bh here to avoid deadlocks and other
874 irq_forced_thread_fn(struct irq_desc
*desc
, struct irqaction
*action
)
879 ret
= action
->thread_fn(action
->irq
, action
->dev_id
);
880 irq_finalize_oneshot(desc
, action
);
886 * Interrupts explicitly requested as threaded interrupts want to be
887 * preemtible - many of them need to sleep and wait for slow busses to
890 static irqreturn_t
irq_thread_fn(struct irq_desc
*desc
,
891 struct irqaction
*action
)
895 ret
= action
->thread_fn(action
->irq
, action
->dev_id
);
896 irq_finalize_oneshot(desc
, action
);
900 static void wake_threads_waitq(struct irq_desc
*desc
)
902 if (atomic_dec_and_test(&desc
->threads_active
))
903 wake_up(&desc
->wait_for_threads
);
906 static void irq_thread_dtor(struct callback_head
*unused
)
908 struct task_struct
*tsk
= current
;
909 struct irq_desc
*desc
;
910 struct irqaction
*action
;
912 if (WARN_ON_ONCE(!(current
->flags
& PF_EXITING
)))
915 action
= kthread_data(tsk
);
917 pr_err("exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n",
918 tsk
->comm
, tsk
->pid
, action
->irq
);
921 desc
= irq_to_desc(action
->irq
);
923 * If IRQTF_RUNTHREAD is set, we need to decrement
924 * desc->threads_active and wake possible waiters.
926 if (test_and_clear_bit(IRQTF_RUNTHREAD
, &action
->thread_flags
))
927 wake_threads_waitq(desc
);
929 /* Prevent a stale desc->threads_oneshot */
930 irq_finalize_oneshot(desc
, action
);
933 static void irq_wake_secondary(struct irq_desc
*desc
, struct irqaction
*action
)
935 struct irqaction
*secondary
= action
->secondary
;
937 if (WARN_ON_ONCE(!secondary
))
940 raw_spin_lock_irq(&desc
->lock
);
941 __irq_wake_thread(desc
, secondary
);
942 raw_spin_unlock_irq(&desc
->lock
);
946 * Interrupt handler thread
948 static int irq_thread(void *data
)
950 struct callback_head on_exit_work
;
951 struct irqaction
*action
= data
;
952 struct irq_desc
*desc
= irq_to_desc(action
->irq
);
953 irqreturn_t (*handler_fn
)(struct irq_desc
*desc
,
954 struct irqaction
*action
);
956 if (force_irqthreads
&& test_bit(IRQTF_FORCED_THREAD
,
957 &action
->thread_flags
))
958 handler_fn
= irq_forced_thread_fn
;
960 handler_fn
= irq_thread_fn
;
962 init_task_work(&on_exit_work
, irq_thread_dtor
);
963 task_work_add(current
, &on_exit_work
, false);
965 irq_thread_check_affinity(desc
, action
);
967 while (!irq_wait_for_interrupt(action
)) {
968 irqreturn_t action_ret
;
970 irq_thread_check_affinity(desc
, action
);
972 action_ret
= handler_fn(desc
, action
);
973 if (action_ret
== IRQ_HANDLED
)
974 atomic_inc(&desc
->threads_handled
);
975 if (action_ret
== IRQ_WAKE_THREAD
)
976 irq_wake_secondary(desc
, action
);
978 wake_threads_waitq(desc
);
982 * This is the regular exit path. __free_irq() is stopping the
983 * thread via kthread_stop() after calling
984 * synchronize_irq(). So neither IRQTF_RUNTHREAD nor the
985 * oneshot mask bit can be set. We cannot verify that as we
986 * cannot touch the oneshot mask at this point anymore as
987 * __setup_irq() might have given out currents thread_mask
990 task_work_cancel(current
, irq_thread_dtor
);
995 * irq_wake_thread - wake the irq thread for the action identified by dev_id
996 * @irq: Interrupt line
997 * @dev_id: Device identity for which the thread should be woken
1000 void irq_wake_thread(unsigned int irq
, void *dev_id
)
1002 struct irq_desc
*desc
= irq_to_desc(irq
);
1003 struct irqaction
*action
;
1004 unsigned long flags
;
1006 if (!desc
|| WARN_ON(irq_settings_is_per_cpu_devid(desc
)))
1009 raw_spin_lock_irqsave(&desc
->lock
, flags
);
1010 for_each_action_of_desc(desc
, action
) {
1011 if (action
->dev_id
== dev_id
) {
1013 __irq_wake_thread(desc
, action
);
1017 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
1019 EXPORT_SYMBOL_GPL(irq_wake_thread
);
1021 static int irq_setup_forced_threading(struct irqaction
*new)
1023 if (!force_irqthreads
)
1025 if (new->flags
& (IRQF_NO_THREAD
| IRQF_PERCPU
| IRQF_ONESHOT
))
1028 new->flags
|= IRQF_ONESHOT
;
1031 * Handle the case where we have a real primary handler and a
1032 * thread handler. We force thread them as well by creating a
1035 if (new->handler
!= irq_default_primary_handler
&& new->thread_fn
) {
1036 /* Allocate the secondary action */
1037 new->secondary
= kzalloc(sizeof(struct irqaction
), GFP_KERNEL
);
1038 if (!new->secondary
)
1040 new->secondary
->handler
= irq_forced_secondary_handler
;
1041 new->secondary
->thread_fn
= new->thread_fn
;
1042 new->secondary
->dev_id
= new->dev_id
;
1043 new->secondary
->irq
= new->irq
;
1044 new->secondary
->name
= new->name
;
1046 /* Deal with the primary handler */
1047 set_bit(IRQTF_FORCED_THREAD
, &new->thread_flags
);
1048 new->thread_fn
= new->handler
;
1049 new->handler
= irq_default_primary_handler
;
1053 static int irq_request_resources(struct irq_desc
*desc
)
1055 struct irq_data
*d
= &desc
->irq_data
;
1056 struct irq_chip
*c
= d
->chip
;
1058 return c
->irq_request_resources
? c
->irq_request_resources(d
) : 0;
1061 static void irq_release_resources(struct irq_desc
*desc
)
1063 struct irq_data
*d
= &desc
->irq_data
;
1064 struct irq_chip
*c
= d
->chip
;
1066 if (c
->irq_release_resources
)
1067 c
->irq_release_resources(d
);
1071 setup_irq_thread(struct irqaction
*new, unsigned int irq
, bool secondary
)
1073 struct task_struct
*t
;
1074 struct sched_param param
= {
1075 .sched_priority
= MAX_USER_RT_PRIO
/2,
1079 t
= kthread_create(irq_thread
, new, "irq/%d-%s", irq
,
1082 t
= kthread_create(irq_thread
, new, "irq/%d-s-%s", irq
,
1084 param
.sched_priority
-= 1;
1090 sched_setscheduler_nocheck(t
, SCHED_FIFO
, ¶m
);
1093 * We keep the reference to the task struct even if
1094 * the thread dies to avoid that the interrupt code
1095 * references an already freed task_struct.
1100 * Tell the thread to set its affinity. This is
1101 * important for shared interrupt handlers as we do
1102 * not invoke setup_affinity() for the secondary
1103 * handlers as everything is already set up. Even for
1104 * interrupts marked with IRQF_NO_BALANCE this is
1105 * correct as we want the thread to move to the cpu(s)
1106 * on which the requesting code placed the interrupt.
1108 set_bit(IRQTF_AFFINITY
, &new->thread_flags
);
1113 * Internal function to register an irqaction - typically used to
1114 * allocate special interrupts that are part of the architecture.
1117 __setup_irq(unsigned int irq
, struct irq_desc
*desc
, struct irqaction
*new)
1119 struct irqaction
*old
, **old_ptr
;
1120 unsigned long flags
, thread_mask
= 0;
1121 int ret
, nested
, shared
= 0;
1127 if (desc
->irq_data
.chip
== &no_irq_chip
)
1129 if (!try_module_get(desc
->owner
))
1135 * If the trigger type is not specified by the caller,
1136 * then use the default for this interrupt.
1138 if (!(new->flags
& IRQF_TRIGGER_MASK
))
1139 new->flags
|= irqd_get_trigger_type(&desc
->irq_data
);
1142 * Check whether the interrupt nests into another interrupt
1145 nested
= irq_settings_is_nested_thread(desc
);
1147 if (!new->thread_fn
) {
1152 * Replace the primary handler which was provided from
1153 * the driver for non nested interrupt handling by the
1154 * dummy function which warns when called.
1156 new->handler
= irq_nested_primary_handler
;
1158 if (irq_settings_can_thread(desc
)) {
1159 ret
= irq_setup_forced_threading(new);
1166 * Create a handler thread when a thread function is supplied
1167 * and the interrupt does not nest into another interrupt
1170 if (new->thread_fn
&& !nested
) {
1171 ret
= setup_irq_thread(new, irq
, false);
1174 if (new->secondary
) {
1175 ret
= setup_irq_thread(new->secondary
, irq
, true);
1181 if (!alloc_cpumask_var(&mask
, GFP_KERNEL
)) {
1187 * Drivers are often written to work w/o knowledge about the
1188 * underlying irq chip implementation, so a request for a
1189 * threaded irq without a primary hard irq context handler
1190 * requires the ONESHOT flag to be set. Some irq chips like
1191 * MSI based interrupts are per se one shot safe. Check the
1192 * chip flags, so we can avoid the unmask dance at the end of
1193 * the threaded handler for those.
1195 if (desc
->irq_data
.chip
->flags
& IRQCHIP_ONESHOT_SAFE
)
1196 new->flags
&= ~IRQF_ONESHOT
;
1199 * The following block of code has to be executed atomically
1201 raw_spin_lock_irqsave(&desc
->lock
, flags
);
1202 old_ptr
= &desc
->action
;
1206 * Can't share interrupts unless both agree to and are
1207 * the same type (level, edge, polarity). So both flag
1208 * fields must have IRQF_SHARED set and the bits which
1209 * set the trigger type must match. Also all must
1212 if (!((old
->flags
& new->flags
) & IRQF_SHARED
) ||
1213 ((old
->flags
^ new->flags
) & IRQF_TRIGGER_MASK
) ||
1214 ((old
->flags
^ new->flags
) & IRQF_ONESHOT
))
1217 /* All handlers must agree on per-cpuness */
1218 if ((old
->flags
& IRQF_PERCPU
) !=
1219 (new->flags
& IRQF_PERCPU
))
1222 /* add new interrupt at end of irq queue */
1225 * Or all existing action->thread_mask bits,
1226 * so we can find the next zero bit for this
1229 thread_mask
|= old
->thread_mask
;
1230 old_ptr
= &old
->next
;
1237 * Setup the thread mask for this irqaction for ONESHOT. For
1238 * !ONESHOT irqs the thread mask is 0 so we can avoid a
1239 * conditional in irq_wake_thread().
1241 if (new->flags
& IRQF_ONESHOT
) {
1243 * Unlikely to have 32 resp 64 irqs sharing one line,
1246 if (thread_mask
== ~0UL) {
1251 * The thread_mask for the action is or'ed to
1252 * desc->thread_active to indicate that the
1253 * IRQF_ONESHOT thread handler has been woken, but not
1254 * yet finished. The bit is cleared when a thread
1255 * completes. When all threads of a shared interrupt
1256 * line have completed desc->threads_active becomes
1257 * zero and the interrupt line is unmasked. See
1258 * handle.c:irq_wake_thread() for further information.
1260 * If no thread is woken by primary (hard irq context)
1261 * interrupt handlers, then desc->threads_active is
1262 * also checked for zero to unmask the irq line in the
1263 * affected hard irq flow handlers
1264 * (handle_[fasteoi|level]_irq).
1266 * The new action gets the first zero bit of
1267 * thread_mask assigned. See the loop above which or's
1268 * all existing action->thread_mask bits.
1270 new->thread_mask
= 1 << ffz(thread_mask
);
1272 } else if (new->handler
== irq_default_primary_handler
&&
1273 !(desc
->irq_data
.chip
->flags
& IRQCHIP_ONESHOT_SAFE
)) {
1275 * The interrupt was requested with handler = NULL, so
1276 * we use the default primary handler for it. But it
1277 * does not have the oneshot flag set. In combination
1278 * with level interrupts this is deadly, because the
1279 * default primary handler just wakes the thread, then
1280 * the irq lines is reenabled, but the device still
1281 * has the level irq asserted. Rinse and repeat....
1283 * While this works for edge type interrupts, we play
1284 * it safe and reject unconditionally because we can't
1285 * say for sure which type this interrupt really
1286 * has. The type flags are unreliable as the
1287 * underlying chip implementation can override them.
1289 pr_err("Threaded irq requested with handler=NULL and !ONESHOT for irq %d\n",
1296 ret
= irq_request_resources(desc
);
1298 pr_err("Failed to request resources for %s (irq %d) on irqchip %s\n",
1299 new->name
, irq
, desc
->irq_data
.chip
->name
);
1303 init_waitqueue_head(&desc
->wait_for_threads
);
1305 /* Setup the type (level, edge polarity) if configured: */
1306 if (new->flags
& IRQF_TRIGGER_MASK
) {
1307 ret
= __irq_set_trigger(desc
,
1308 new->flags
& IRQF_TRIGGER_MASK
);
1314 desc
->istate
&= ~(IRQS_AUTODETECT
| IRQS_SPURIOUS_DISABLED
| \
1315 IRQS_ONESHOT
| IRQS_WAITING
);
1316 irqd_clear(&desc
->irq_data
, IRQD_IRQ_INPROGRESS
);
1318 if (new->flags
& IRQF_PERCPU
) {
1319 irqd_set(&desc
->irq_data
, IRQD_PER_CPU
);
1320 irq_settings_set_per_cpu(desc
);
1323 if (new->flags
& IRQF_ONESHOT
)
1324 desc
->istate
|= IRQS_ONESHOT
;
1326 if (irq_settings_can_autoenable(desc
))
1327 irq_startup(desc
, true);
1329 /* Undo nested disables: */
1332 /* Exclude IRQ from balancing if requested */
1333 if (new->flags
& IRQF_NOBALANCING
) {
1334 irq_settings_set_no_balancing(desc
);
1335 irqd_set(&desc
->irq_data
, IRQD_NO_BALANCING
);
1338 /* Set default affinity mask once everything is setup */
1339 setup_affinity(desc
, mask
);
1341 } else if (new->flags
& IRQF_TRIGGER_MASK
) {
1342 unsigned int nmsk
= new->flags
& IRQF_TRIGGER_MASK
;
1343 unsigned int omsk
= irq_settings_get_trigger_mask(desc
);
1346 /* hope the handler works with current trigger mode */
1347 pr_warn("irq %d uses trigger mode %u; requested %u\n",
1353 irq_pm_install_action(desc
, new);
1355 /* Reset broken irq detection when installing new handler */
1356 desc
->irq_count
= 0;
1357 desc
->irqs_unhandled
= 0;
1360 * Check whether we disabled the irq via the spurious handler
1361 * before. Reenable it and give it another chance.
1363 if (shared
&& (desc
->istate
& IRQS_SPURIOUS_DISABLED
)) {
1364 desc
->istate
&= ~IRQS_SPURIOUS_DISABLED
;
1368 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
1371 * Strictly no need to wake it up, but hung_task complains
1372 * when no hard interrupt wakes the thread up.
1375 wake_up_process(new->thread
);
1377 wake_up_process(new->secondary
->thread
);
1379 register_irq_proc(irq
, desc
);
1381 register_handler_proc(irq
, new);
1382 free_cpumask_var(mask
);
1387 if (!(new->flags
& IRQF_PROBE_SHARED
)) {
1388 pr_err("Flags mismatch irq %d. %08x (%s) vs. %08x (%s)\n",
1389 irq
, new->flags
, new->name
, old
->flags
, old
->name
);
1390 #ifdef CONFIG_DEBUG_SHIRQ
1397 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
1398 free_cpumask_var(mask
);
1402 struct task_struct
*t
= new->thread
;
1408 if (new->secondary
&& new->secondary
->thread
) {
1409 struct task_struct
*t
= new->secondary
->thread
;
1411 new->secondary
->thread
= NULL
;
1416 module_put(desc
->owner
);
1421 * setup_irq - setup an interrupt
1422 * @irq: Interrupt line to setup
1423 * @act: irqaction for the interrupt
1425 * Used to statically setup interrupts in the early boot process.
1427 int setup_irq(unsigned int irq
, struct irqaction
*act
)
1430 struct irq_desc
*desc
= irq_to_desc(irq
);
1432 if (!desc
|| WARN_ON(irq_settings_is_per_cpu_devid(desc
)))
1435 retval
= irq_chip_pm_get(&desc
->irq_data
);
1439 chip_bus_lock(desc
);
1440 retval
= __setup_irq(irq
, desc
, act
);
1441 chip_bus_sync_unlock(desc
);
1444 irq_chip_pm_put(&desc
->irq_data
);
1448 EXPORT_SYMBOL_GPL(setup_irq
);
1451 * Internal function to unregister an irqaction - used to free
1452 * regular and special interrupts that are part of the architecture.
1454 static struct irqaction
*__free_irq(unsigned int irq
, void *dev_id
)
1456 struct irq_desc
*desc
= irq_to_desc(irq
);
1457 struct irqaction
*action
, **action_ptr
;
1458 unsigned long flags
;
1460 WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq
);
1465 chip_bus_lock(desc
);
1466 raw_spin_lock_irqsave(&desc
->lock
, flags
);
1469 * There can be multiple actions per IRQ descriptor, find the right
1470 * one based on the dev_id:
1472 action_ptr
= &desc
->action
;
1474 action
= *action_ptr
;
1477 WARN(1, "Trying to free already-free IRQ %d\n", irq
);
1478 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
1479 chip_bus_sync_unlock(desc
);
1483 if (action
->dev_id
== dev_id
)
1485 action_ptr
= &action
->next
;
1488 /* Found it - now remove it from the list of entries: */
1489 *action_ptr
= action
->next
;
1491 irq_pm_remove_action(desc
, action
);
1493 /* If this was the last handler, shut down the IRQ line: */
1494 if (!desc
->action
) {
1495 irq_settings_clr_disable_unlazy(desc
);
1497 irq_release_resources(desc
);
1501 /* make sure affinity_hint is cleaned up */
1502 if (WARN_ON_ONCE(desc
->affinity_hint
))
1503 desc
->affinity_hint
= NULL
;
1506 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
1507 chip_bus_sync_unlock(desc
);
1509 unregister_handler_proc(irq
, action
);
1511 /* Make sure it's not being used on another CPU: */
1512 synchronize_irq(irq
);
1514 #ifdef CONFIG_DEBUG_SHIRQ
1516 * It's a shared IRQ -- the driver ought to be prepared for an IRQ
1517 * event to happen even now it's being freed, so let's make sure that
1518 * is so by doing an extra call to the handler ....
1520 * ( We do this after actually deregistering it, to make sure that a
1521 * 'real' IRQ doesn't run in * parallel with our fake. )
1523 if (action
->flags
& IRQF_SHARED
) {
1524 local_irq_save(flags
);
1525 action
->handler(irq
, dev_id
);
1526 local_irq_restore(flags
);
1530 if (action
->thread
) {
1531 kthread_stop(action
->thread
);
1532 put_task_struct(action
->thread
);
1533 if (action
->secondary
&& action
->secondary
->thread
) {
1534 kthread_stop(action
->secondary
->thread
);
1535 put_task_struct(action
->secondary
->thread
);
1539 irq_chip_pm_put(&desc
->irq_data
);
1540 module_put(desc
->owner
);
1541 kfree(action
->secondary
);
1546 * remove_irq - free an interrupt
1547 * @irq: Interrupt line to free
1548 * @act: irqaction for the interrupt
1550 * Used to remove interrupts statically setup by the early boot process.
1552 void remove_irq(unsigned int irq
, struct irqaction
*act
)
1554 struct irq_desc
*desc
= irq_to_desc(irq
);
1556 if (desc
&& !WARN_ON(irq_settings_is_per_cpu_devid(desc
)))
1557 __free_irq(irq
, act
->dev_id
);
1559 EXPORT_SYMBOL_GPL(remove_irq
);
1562 * free_irq - free an interrupt allocated with request_irq
1563 * @irq: Interrupt line to free
1564 * @dev_id: Device identity to free
1566 * Remove an interrupt handler. The handler is removed and if the
1567 * interrupt line is no longer in use by any driver it is disabled.
1568 * On a shared IRQ the caller must ensure the interrupt is disabled
1569 * on the card it drives before calling this function. The function
1570 * does not return until any executing interrupts for this IRQ
1573 * This function must not be called from interrupt context.
1575 void free_irq(unsigned int irq
, void *dev_id
)
1577 struct irq_desc
*desc
= irq_to_desc(irq
);
1579 if (!desc
|| WARN_ON(irq_settings_is_per_cpu_devid(desc
)))
1583 if (WARN_ON(desc
->affinity_notify
))
1584 desc
->affinity_notify
= NULL
;
1587 kfree(__free_irq(irq
, dev_id
));
1589 EXPORT_SYMBOL(free_irq
);
1592 * request_threaded_irq - allocate an interrupt line
1593 * @irq: Interrupt line to allocate
1594 * @handler: Function to be called when the IRQ occurs.
1595 * Primary handler for threaded interrupts
1596 * If NULL and thread_fn != NULL the default
1597 * primary handler is installed
1598 * @thread_fn: Function called from the irq handler thread
1599 * If NULL, no irq thread is created
1600 * @irqflags: Interrupt type flags
1601 * @devname: An ascii name for the claiming device
1602 * @dev_id: A cookie passed back to the handler function
1604 * This call allocates interrupt resources and enables the
1605 * interrupt line and IRQ handling. From the point this
1606 * call is made your handler function may be invoked. Since
1607 * your handler function must clear any interrupt the board
1608 * raises, you must take care both to initialise your hardware
1609 * and to set up the interrupt handler in the right order.
1611 * If you want to set up a threaded irq handler for your device
1612 * then you need to supply @handler and @thread_fn. @handler is
1613 * still called in hard interrupt context and has to check
1614 * whether the interrupt originates from the device. If yes it
1615 * needs to disable the interrupt on the device and return
1616 * IRQ_WAKE_THREAD which will wake up the handler thread and run
1617 * @thread_fn. This split handler design is necessary to support
1618 * shared interrupts.
1620 * Dev_id must be globally unique. Normally the address of the
1621 * device data structure is used as the cookie. Since the handler
1622 * receives this value it makes sense to use it.
1624 * If your interrupt is shared you must pass a non NULL dev_id
1625 * as this is required when freeing the interrupt.
1629 * IRQF_SHARED Interrupt is shared
1630 * IRQF_TRIGGER_* Specify active edge(s) or level
1633 int request_threaded_irq(unsigned int irq
, irq_handler_t handler
,
1634 irq_handler_t thread_fn
, unsigned long irqflags
,
1635 const char *devname
, void *dev_id
)
1637 struct irqaction
*action
;
1638 struct irq_desc
*desc
;
1641 if (irq
== IRQ_NOTCONNECTED
)
1645 * Sanity-check: shared interrupts must pass in a real dev-ID,
1646 * otherwise we'll have trouble later trying to figure out
1647 * which interrupt is which (messes up the interrupt freeing
1650 * Also IRQF_COND_SUSPEND only makes sense for shared interrupts and
1651 * it cannot be set along with IRQF_NO_SUSPEND.
1653 if (((irqflags
& IRQF_SHARED
) && !dev_id
) ||
1654 (!(irqflags
& IRQF_SHARED
) && (irqflags
& IRQF_COND_SUSPEND
)) ||
1655 ((irqflags
& IRQF_NO_SUSPEND
) && (irqflags
& IRQF_COND_SUSPEND
)))
1658 desc
= irq_to_desc(irq
);
1662 if (!irq_settings_can_request(desc
) ||
1663 WARN_ON(irq_settings_is_per_cpu_devid(desc
)))
1669 handler
= irq_default_primary_handler
;
1672 action
= kzalloc(sizeof(struct irqaction
), GFP_KERNEL
);
1676 action
->handler
= handler
;
1677 action
->thread_fn
= thread_fn
;
1678 action
->flags
= irqflags
;
1679 action
->name
= devname
;
1680 action
->dev_id
= dev_id
;
1682 retval
= irq_chip_pm_get(&desc
->irq_data
);
1688 chip_bus_lock(desc
);
1689 retval
= __setup_irq(irq
, desc
, action
);
1690 chip_bus_sync_unlock(desc
);
1693 irq_chip_pm_put(&desc
->irq_data
);
1694 kfree(action
->secondary
);
1698 #ifdef CONFIG_DEBUG_SHIRQ_FIXME
1699 if (!retval
&& (irqflags
& IRQF_SHARED
)) {
1701 * It's a shared IRQ -- the driver ought to be prepared for it
1702 * to happen immediately, so let's make sure....
1703 * We disable the irq to make sure that a 'real' IRQ doesn't
1704 * run in parallel with our fake.
1706 unsigned long flags
;
1709 local_irq_save(flags
);
1711 handler(irq
, dev_id
);
1713 local_irq_restore(flags
);
1719 EXPORT_SYMBOL(request_threaded_irq
);
1722 * request_any_context_irq - allocate an interrupt line
1723 * @irq: Interrupt line to allocate
1724 * @handler: Function to be called when the IRQ occurs.
1725 * Threaded handler for threaded interrupts.
1726 * @flags: Interrupt type flags
1727 * @name: An ascii name for the claiming device
1728 * @dev_id: A cookie passed back to the handler function
1730 * This call allocates interrupt resources and enables the
1731 * interrupt line and IRQ handling. It selects either a
1732 * hardirq or threaded handling method depending on the
1735 * On failure, it returns a negative value. On success,
1736 * it returns either IRQC_IS_HARDIRQ or IRQC_IS_NESTED.
1738 int request_any_context_irq(unsigned int irq
, irq_handler_t handler
,
1739 unsigned long flags
, const char *name
, void *dev_id
)
1741 struct irq_desc
*desc
;
1744 if (irq
== IRQ_NOTCONNECTED
)
1747 desc
= irq_to_desc(irq
);
1751 if (irq_settings_is_nested_thread(desc
)) {
1752 ret
= request_threaded_irq(irq
, NULL
, handler
,
1753 flags
, name
, dev_id
);
1754 return !ret
? IRQC_IS_NESTED
: ret
;
1757 ret
= request_irq(irq
, handler
, flags
, name
, dev_id
);
1758 return !ret
? IRQC_IS_HARDIRQ
: ret
;
1760 EXPORT_SYMBOL_GPL(request_any_context_irq
);
1762 void enable_percpu_irq(unsigned int irq
, unsigned int type
)
1764 unsigned int cpu
= smp_processor_id();
1765 unsigned long flags
;
1766 struct irq_desc
*desc
= irq_get_desc_lock(irq
, &flags
, IRQ_GET_DESC_CHECK_PERCPU
);
1772 * If the trigger type is not specified by the caller, then
1773 * use the default for this interrupt.
1775 type
&= IRQ_TYPE_SENSE_MASK
;
1776 if (type
== IRQ_TYPE_NONE
)
1777 type
= irqd_get_trigger_type(&desc
->irq_data
);
1779 if (type
!= IRQ_TYPE_NONE
) {
1782 ret
= __irq_set_trigger(desc
, type
);
1785 WARN(1, "failed to set type for IRQ%d\n", irq
);
1790 irq_percpu_enable(desc
, cpu
);
1792 irq_put_desc_unlock(desc
, flags
);
1794 EXPORT_SYMBOL_GPL(enable_percpu_irq
);
1797 * irq_percpu_is_enabled - Check whether the per cpu irq is enabled
1798 * @irq: Linux irq number to check for
1800 * Must be called from a non migratable context. Returns the enable
1801 * state of a per cpu interrupt on the current cpu.
1803 bool irq_percpu_is_enabled(unsigned int irq
)
1805 unsigned int cpu
= smp_processor_id();
1806 struct irq_desc
*desc
;
1807 unsigned long flags
;
1810 desc
= irq_get_desc_lock(irq
, &flags
, IRQ_GET_DESC_CHECK_PERCPU
);
1814 is_enabled
= cpumask_test_cpu(cpu
, desc
->percpu_enabled
);
1815 irq_put_desc_unlock(desc
, flags
);
1819 EXPORT_SYMBOL_GPL(irq_percpu_is_enabled
);
1821 void disable_percpu_irq(unsigned int irq
)
1823 unsigned int cpu
= smp_processor_id();
1824 unsigned long flags
;
1825 struct irq_desc
*desc
= irq_get_desc_lock(irq
, &flags
, IRQ_GET_DESC_CHECK_PERCPU
);
1830 irq_percpu_disable(desc
, cpu
);
1831 irq_put_desc_unlock(desc
, flags
);
1833 EXPORT_SYMBOL_GPL(disable_percpu_irq
);
1836 * Internal function to unregister a percpu irqaction.
1838 static struct irqaction
*__free_percpu_irq(unsigned int irq
, void __percpu
*dev_id
)
1840 struct irq_desc
*desc
= irq_to_desc(irq
);
1841 struct irqaction
*action
;
1842 unsigned long flags
;
1844 WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq
);
1849 raw_spin_lock_irqsave(&desc
->lock
, flags
);
1851 action
= desc
->action
;
1852 if (!action
|| action
->percpu_dev_id
!= dev_id
) {
1853 WARN(1, "Trying to free already-free IRQ %d\n", irq
);
1857 if (!cpumask_empty(desc
->percpu_enabled
)) {
1858 WARN(1, "percpu IRQ %d still enabled on CPU%d!\n",
1859 irq
, cpumask_first(desc
->percpu_enabled
));
1863 /* Found it - now remove it from the list of entries: */
1864 desc
->action
= NULL
;
1866 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
1868 unregister_handler_proc(irq
, action
);
1870 irq_chip_pm_put(&desc
->irq_data
);
1871 module_put(desc
->owner
);
1875 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
1880 * remove_percpu_irq - free a per-cpu interrupt
1881 * @irq: Interrupt line to free
1882 * @act: irqaction for the interrupt
1884 * Used to remove interrupts statically setup by the early boot process.
1886 void remove_percpu_irq(unsigned int irq
, struct irqaction
*act
)
1888 struct irq_desc
*desc
= irq_to_desc(irq
);
1890 if (desc
&& irq_settings_is_per_cpu_devid(desc
))
1891 __free_percpu_irq(irq
, act
->percpu_dev_id
);
1895 * free_percpu_irq - free an interrupt allocated with request_percpu_irq
1896 * @irq: Interrupt line to free
1897 * @dev_id: Device identity to free
1899 * Remove a percpu interrupt handler. The handler is removed, but
1900 * the interrupt line is not disabled. This must be done on each
1901 * CPU before calling this function. The function does not return
1902 * until any executing interrupts for this IRQ have completed.
1904 * This function must not be called from interrupt context.
1906 void free_percpu_irq(unsigned int irq
, void __percpu
*dev_id
)
1908 struct irq_desc
*desc
= irq_to_desc(irq
);
1910 if (!desc
|| !irq_settings_is_per_cpu_devid(desc
))
1913 chip_bus_lock(desc
);
1914 kfree(__free_percpu_irq(irq
, dev_id
));
1915 chip_bus_sync_unlock(desc
);
1917 EXPORT_SYMBOL_GPL(free_percpu_irq
);
1920 * setup_percpu_irq - setup a per-cpu interrupt
1921 * @irq: Interrupt line to setup
1922 * @act: irqaction for the interrupt
1924 * Used to statically setup per-cpu interrupts in the early boot process.
1926 int setup_percpu_irq(unsigned int irq
, struct irqaction
*act
)
1928 struct irq_desc
*desc
= irq_to_desc(irq
);
1931 if (!desc
|| !irq_settings_is_per_cpu_devid(desc
))
1934 retval
= irq_chip_pm_get(&desc
->irq_data
);
1938 chip_bus_lock(desc
);
1939 retval
= __setup_irq(irq
, desc
, act
);
1940 chip_bus_sync_unlock(desc
);
1943 irq_chip_pm_put(&desc
->irq_data
);
1949 * request_percpu_irq - allocate a percpu interrupt line
1950 * @irq: Interrupt line to allocate
1951 * @handler: Function to be called when the IRQ occurs.
1952 * @devname: An ascii name for the claiming device
1953 * @dev_id: A percpu cookie passed back to the handler function
1955 * This call allocates interrupt resources and enables the
1956 * interrupt on the local CPU. If the interrupt is supposed to be
1957 * enabled on other CPUs, it has to be done on each CPU using
1958 * enable_percpu_irq().
1960 * Dev_id must be globally unique. It is a per-cpu variable, and
1961 * the handler gets called with the interrupted CPU's instance of
1964 int request_percpu_irq(unsigned int irq
, irq_handler_t handler
,
1965 const char *devname
, void __percpu
*dev_id
)
1967 struct irqaction
*action
;
1968 struct irq_desc
*desc
;
1974 desc
= irq_to_desc(irq
);
1975 if (!desc
|| !irq_settings_can_request(desc
) ||
1976 !irq_settings_is_per_cpu_devid(desc
))
1979 action
= kzalloc(sizeof(struct irqaction
), GFP_KERNEL
);
1983 action
->handler
= handler
;
1984 action
->flags
= IRQF_PERCPU
| IRQF_NO_SUSPEND
;
1985 action
->name
= devname
;
1986 action
->percpu_dev_id
= dev_id
;
1988 retval
= irq_chip_pm_get(&desc
->irq_data
);
1994 chip_bus_lock(desc
);
1995 retval
= __setup_irq(irq
, desc
, action
);
1996 chip_bus_sync_unlock(desc
);
1999 irq_chip_pm_put(&desc
->irq_data
);
2005 EXPORT_SYMBOL_GPL(request_percpu_irq
);
2008 * irq_get_irqchip_state - returns the irqchip state of a interrupt.
2009 * @irq: Interrupt line that is forwarded to a VM
2010 * @which: One of IRQCHIP_STATE_* the caller wants to know about
2011 * @state: a pointer to a boolean where the state is to be storeed
2013 * This call snapshots the internal irqchip state of an
2014 * interrupt, returning into @state the bit corresponding to
2017 * This function should be called with preemption disabled if the
2018 * interrupt controller has per-cpu registers.
2020 int irq_get_irqchip_state(unsigned int irq
, enum irqchip_irq_state which
,
2023 struct irq_desc
*desc
;
2024 struct irq_data
*data
;
2025 struct irq_chip
*chip
;
2026 unsigned long flags
;
2029 desc
= irq_get_desc_buslock(irq
, &flags
, 0);
2033 data
= irq_desc_get_irq_data(desc
);
2036 chip
= irq_data_get_irq_chip(data
);
2037 if (chip
->irq_get_irqchip_state
)
2039 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
2040 data
= data
->parent_data
;
2047 err
= chip
->irq_get_irqchip_state(data
, which
, state
);
2049 irq_put_desc_busunlock(desc
, flags
);
2052 EXPORT_SYMBOL_GPL(irq_get_irqchip_state
);
2055 * irq_set_irqchip_state - set the state of a forwarded interrupt.
2056 * @irq: Interrupt line that is forwarded to a VM
2057 * @which: State to be restored (one of IRQCHIP_STATE_*)
2058 * @val: Value corresponding to @which
2060 * This call sets the internal irqchip state of an interrupt,
2061 * depending on the value of @which.
2063 * This function should be called with preemption disabled if the
2064 * interrupt controller has per-cpu registers.
2066 int irq_set_irqchip_state(unsigned int irq
, enum irqchip_irq_state which
,
2069 struct irq_desc
*desc
;
2070 struct irq_data
*data
;
2071 struct irq_chip
*chip
;
2072 unsigned long flags
;
2075 desc
= irq_get_desc_buslock(irq
, &flags
, 0);
2079 data
= irq_desc_get_irq_data(desc
);
2082 chip
= irq_data_get_irq_chip(data
);
2083 if (chip
->irq_set_irqchip_state
)
2085 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
2086 data
= data
->parent_data
;
2093 err
= chip
->irq_set_irqchip_state(data
, which
, val
);
2095 irq_put_desc_busunlock(desc
, flags
);
2098 EXPORT_SYMBOL_GPL(irq_set_irqchip_state
);