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 check_irq_resend(desc
);
546 * enable_irq - enable handling of an irq
547 * @irq: Interrupt to enable
549 * Undoes the effect of one call to disable_irq(). If this
550 * matches the last disable, processing of interrupts on this
551 * IRQ line is re-enabled.
553 * This function may be called from IRQ context only when
554 * desc->irq_data.chip->bus_lock and desc->chip->bus_sync_unlock are NULL !
556 void enable_irq(unsigned int irq
)
559 struct irq_desc
*desc
= irq_get_desc_buslock(irq
, &flags
, IRQ_GET_DESC_CHECK_GLOBAL
);
563 if (WARN(!desc
->irq_data
.chip
,
564 KERN_ERR
"enable_irq before setup/request_irq: irq %u\n", irq
))
569 irq_put_desc_busunlock(desc
, flags
);
571 EXPORT_SYMBOL(enable_irq
);
573 static int set_irq_wake_real(unsigned int irq
, unsigned int on
)
575 struct irq_desc
*desc
= irq_to_desc(irq
);
578 if (irq_desc_get_chip(desc
)->flags
& IRQCHIP_SKIP_SET_WAKE
)
581 if (desc
->irq_data
.chip
->irq_set_wake
)
582 ret
= desc
->irq_data
.chip
->irq_set_wake(&desc
->irq_data
, on
);
588 * irq_set_irq_wake - control irq power management wakeup
589 * @irq: interrupt to control
590 * @on: enable/disable power management wakeup
592 * Enable/disable power management wakeup mode, which is
593 * disabled by default. Enables and disables must match,
594 * just as they match for non-wakeup mode support.
596 * Wakeup mode lets this IRQ wake the system from sleep
597 * states like "suspend to RAM".
599 int irq_set_irq_wake(unsigned int irq
, unsigned int on
)
602 struct irq_desc
*desc
= irq_get_desc_buslock(irq
, &flags
, IRQ_GET_DESC_CHECK_GLOBAL
);
608 /* wakeup-capable irqs can be shared between drivers that
609 * don't need to have the same sleep mode behaviors.
612 if (desc
->wake_depth
++ == 0) {
613 ret
= set_irq_wake_real(irq
, on
);
615 desc
->wake_depth
= 0;
617 irqd_set(&desc
->irq_data
, IRQD_WAKEUP_STATE
);
620 if (desc
->wake_depth
== 0) {
621 WARN(1, "Unbalanced IRQ %d wake disable\n", irq
);
622 } else if (--desc
->wake_depth
== 0) {
623 ret
= set_irq_wake_real(irq
, on
);
625 desc
->wake_depth
= 1;
627 irqd_clear(&desc
->irq_data
, IRQD_WAKEUP_STATE
);
630 irq_put_desc_busunlock(desc
, flags
);
633 EXPORT_SYMBOL(irq_set_irq_wake
);
636 * Internal function that tells the architecture code whether a
637 * particular irq has been exclusively allocated or is available
640 int can_request_irq(unsigned int irq
, unsigned long irqflags
)
643 struct irq_desc
*desc
= irq_get_desc_lock(irq
, &flags
, 0);
649 if (irq_settings_can_request(desc
)) {
651 irqflags
& desc
->action
->flags
& IRQF_SHARED
)
654 irq_put_desc_unlock(desc
, flags
);
658 int __irq_set_trigger(struct irq_desc
*desc
, unsigned long flags
)
660 struct irq_chip
*chip
= desc
->irq_data
.chip
;
663 if (!chip
|| !chip
->irq_set_type
) {
665 * IRQF_TRIGGER_* but the PIC does not support multiple
668 pr_debug("No set_type function for IRQ %d (%s)\n",
669 irq_desc_get_irq(desc
),
670 chip
? (chip
->name
? : "unknown") : "unknown");
674 if (chip
->flags
& IRQCHIP_SET_TYPE_MASKED
) {
675 if (!irqd_irq_masked(&desc
->irq_data
))
677 if (!irqd_irq_disabled(&desc
->irq_data
))
681 /* Mask all flags except trigger mode */
682 flags
&= IRQ_TYPE_SENSE_MASK
;
683 ret
= chip
->irq_set_type(&desc
->irq_data
, flags
);
686 case IRQ_SET_MASK_OK
:
687 case IRQ_SET_MASK_OK_DONE
:
688 irqd_clear(&desc
->irq_data
, IRQD_TRIGGER_MASK
);
689 irqd_set(&desc
->irq_data
, flags
);
691 case IRQ_SET_MASK_OK_NOCOPY
:
692 flags
= irqd_get_trigger_type(&desc
->irq_data
);
693 irq_settings_set_trigger_mask(desc
, flags
);
694 irqd_clear(&desc
->irq_data
, IRQD_LEVEL
);
695 irq_settings_clr_level(desc
);
696 if (flags
& IRQ_TYPE_LEVEL_MASK
) {
697 irq_settings_set_level(desc
);
698 irqd_set(&desc
->irq_data
, IRQD_LEVEL
);
704 pr_err("Setting trigger mode %lu for irq %u failed (%pF)\n",
705 flags
, irq_desc_get_irq(desc
), chip
->irq_set_type
);
712 #ifdef CONFIG_HARDIRQS_SW_RESEND
713 int irq_set_parent(int irq
, int parent_irq
)
716 struct irq_desc
*desc
= irq_get_desc_lock(irq
, &flags
, 0);
721 desc
->parent_irq
= parent_irq
;
723 irq_put_desc_unlock(desc
, flags
);
726 EXPORT_SYMBOL_GPL(irq_set_parent
);
730 * Default primary interrupt handler for threaded interrupts. Is
731 * assigned as primary handler when request_threaded_irq is called
732 * with handler == NULL. Useful for oneshot interrupts.
734 static irqreturn_t
irq_default_primary_handler(int irq
, void *dev_id
)
736 return IRQ_WAKE_THREAD
;
740 * Primary handler for nested threaded interrupts. Should never be
743 static irqreturn_t
irq_nested_primary_handler(int irq
, void *dev_id
)
745 WARN(1, "Primary handler called for nested irq %d\n", irq
);
749 static irqreturn_t
irq_forced_secondary_handler(int irq
, void *dev_id
)
751 WARN(1, "Secondary action handler called for irq %d\n", irq
);
755 static int irq_wait_for_interrupt(struct irqaction
*action
)
757 set_current_state(TASK_INTERRUPTIBLE
);
759 while (!kthread_should_stop()) {
761 if (test_and_clear_bit(IRQTF_RUNTHREAD
,
762 &action
->thread_flags
)) {
763 __set_current_state(TASK_RUNNING
);
767 set_current_state(TASK_INTERRUPTIBLE
);
769 __set_current_state(TASK_RUNNING
);
774 * Oneshot interrupts keep the irq line masked until the threaded
775 * handler finished. unmask if the interrupt has not been disabled and
778 static void irq_finalize_oneshot(struct irq_desc
*desc
,
779 struct irqaction
*action
)
781 if (!(desc
->istate
& IRQS_ONESHOT
) ||
782 action
->handler
== irq_forced_secondary_handler
)
786 raw_spin_lock_irq(&desc
->lock
);
789 * Implausible though it may be we need to protect us against
790 * the following scenario:
792 * The thread is faster done than the hard interrupt handler
793 * on the other CPU. If we unmask the irq line then the
794 * interrupt can come in again and masks the line, leaves due
795 * to IRQS_INPROGRESS and the irq line is masked forever.
797 * This also serializes the state of shared oneshot handlers
798 * versus "desc->threads_onehsot |= action->thread_mask;" in
799 * irq_wake_thread(). See the comment there which explains the
802 if (unlikely(irqd_irq_inprogress(&desc
->irq_data
))) {
803 raw_spin_unlock_irq(&desc
->lock
);
804 chip_bus_sync_unlock(desc
);
810 * Now check again, whether the thread should run. Otherwise
811 * we would clear the threads_oneshot bit of this thread which
814 if (test_bit(IRQTF_RUNTHREAD
, &action
->thread_flags
))
817 desc
->threads_oneshot
&= ~action
->thread_mask
;
819 if (!desc
->threads_oneshot
&& !irqd_irq_disabled(&desc
->irq_data
) &&
820 irqd_irq_masked(&desc
->irq_data
))
821 unmask_threaded_irq(desc
);
824 raw_spin_unlock_irq(&desc
->lock
);
825 chip_bus_sync_unlock(desc
);
830 * Check whether we need to change the affinity of the interrupt thread.
833 irq_thread_check_affinity(struct irq_desc
*desc
, struct irqaction
*action
)
838 if (!test_and_clear_bit(IRQTF_AFFINITY
, &action
->thread_flags
))
842 * In case we are out of memory we set IRQTF_AFFINITY again and
843 * try again next time
845 if (!alloc_cpumask_var(&mask
, GFP_KERNEL
)) {
846 set_bit(IRQTF_AFFINITY
, &action
->thread_flags
);
850 raw_spin_lock_irq(&desc
->lock
);
852 * This code is triggered unconditionally. Check the affinity
853 * mask pointer. For CPU_MASK_OFFSTACK=n this is optimized out.
855 if (desc
->irq_common_data
.affinity
)
856 cpumask_copy(mask
, desc
->irq_common_data
.affinity
);
859 raw_spin_unlock_irq(&desc
->lock
);
862 set_cpus_allowed_ptr(current
, mask
);
863 free_cpumask_var(mask
);
867 irq_thread_check_affinity(struct irq_desc
*desc
, struct irqaction
*action
) { }
871 * Interrupts which are not explicitely requested as threaded
872 * interrupts rely on the implicit bh/preempt disable of the hard irq
873 * context. So we need to disable bh here to avoid deadlocks and other
877 irq_forced_thread_fn(struct irq_desc
*desc
, struct irqaction
*action
)
882 ret
= action
->thread_fn(action
->irq
, action
->dev_id
);
883 irq_finalize_oneshot(desc
, action
);
889 * Interrupts explicitly requested as threaded interrupts want to be
890 * preemtible - many of them need to sleep and wait for slow busses to
893 static irqreturn_t
irq_thread_fn(struct irq_desc
*desc
,
894 struct irqaction
*action
)
898 ret
= action
->thread_fn(action
->irq
, action
->dev_id
);
899 irq_finalize_oneshot(desc
, action
);
903 static void wake_threads_waitq(struct irq_desc
*desc
)
905 if (atomic_dec_and_test(&desc
->threads_active
))
906 wake_up(&desc
->wait_for_threads
);
909 static void irq_thread_dtor(struct callback_head
*unused
)
911 struct task_struct
*tsk
= current
;
912 struct irq_desc
*desc
;
913 struct irqaction
*action
;
915 if (WARN_ON_ONCE(!(current
->flags
& PF_EXITING
)))
918 action
= kthread_data(tsk
);
920 pr_err("exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n",
921 tsk
->comm
, tsk
->pid
, action
->irq
);
924 desc
= irq_to_desc(action
->irq
);
926 * If IRQTF_RUNTHREAD is set, we need to decrement
927 * desc->threads_active and wake possible waiters.
929 if (test_and_clear_bit(IRQTF_RUNTHREAD
, &action
->thread_flags
))
930 wake_threads_waitq(desc
);
932 /* Prevent a stale desc->threads_oneshot */
933 irq_finalize_oneshot(desc
, action
);
936 static void irq_wake_secondary(struct irq_desc
*desc
, struct irqaction
*action
)
938 struct irqaction
*secondary
= action
->secondary
;
940 if (WARN_ON_ONCE(!secondary
))
943 raw_spin_lock_irq(&desc
->lock
);
944 __irq_wake_thread(desc
, secondary
);
945 raw_spin_unlock_irq(&desc
->lock
);
949 * Interrupt handler thread
951 static int irq_thread(void *data
)
953 struct callback_head on_exit_work
;
954 struct irqaction
*action
= data
;
955 struct irq_desc
*desc
= irq_to_desc(action
->irq
);
956 irqreturn_t (*handler_fn
)(struct irq_desc
*desc
,
957 struct irqaction
*action
);
959 if (force_irqthreads
&& test_bit(IRQTF_FORCED_THREAD
,
960 &action
->thread_flags
))
961 handler_fn
= irq_forced_thread_fn
;
963 handler_fn
= irq_thread_fn
;
965 init_task_work(&on_exit_work
, irq_thread_dtor
);
966 task_work_add(current
, &on_exit_work
, false);
968 irq_thread_check_affinity(desc
, action
);
970 while (!irq_wait_for_interrupt(action
)) {
971 irqreturn_t action_ret
;
973 irq_thread_check_affinity(desc
, action
);
975 action_ret
= handler_fn(desc
, action
);
976 if (action_ret
== IRQ_HANDLED
)
977 atomic_inc(&desc
->threads_handled
);
978 if (action_ret
== IRQ_WAKE_THREAD
)
979 irq_wake_secondary(desc
, action
);
981 wake_threads_waitq(desc
);
985 * This is the regular exit path. __free_irq() is stopping the
986 * thread via kthread_stop() after calling
987 * synchronize_irq(). So neither IRQTF_RUNTHREAD nor the
988 * oneshot mask bit can be set. We cannot verify that as we
989 * cannot touch the oneshot mask at this point anymore as
990 * __setup_irq() might have given out currents thread_mask
993 task_work_cancel(current
, irq_thread_dtor
);
998 * irq_wake_thread - wake the irq thread for the action identified by dev_id
999 * @irq: Interrupt line
1000 * @dev_id: Device identity for which the thread should be woken
1003 void irq_wake_thread(unsigned int irq
, void *dev_id
)
1005 struct irq_desc
*desc
= irq_to_desc(irq
);
1006 struct irqaction
*action
;
1007 unsigned long flags
;
1009 if (!desc
|| WARN_ON(irq_settings_is_per_cpu_devid(desc
)))
1012 raw_spin_lock_irqsave(&desc
->lock
, flags
);
1013 for_each_action_of_desc(desc
, action
) {
1014 if (action
->dev_id
== dev_id
) {
1016 __irq_wake_thread(desc
, action
);
1020 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
1022 EXPORT_SYMBOL_GPL(irq_wake_thread
);
1024 static int irq_setup_forced_threading(struct irqaction
*new)
1026 if (!force_irqthreads
)
1028 if (new->flags
& (IRQF_NO_THREAD
| IRQF_PERCPU
| IRQF_ONESHOT
))
1031 new->flags
|= IRQF_ONESHOT
;
1034 * Handle the case where we have a real primary handler and a
1035 * thread handler. We force thread them as well by creating a
1038 if (new->handler
!= irq_default_primary_handler
&& new->thread_fn
) {
1039 /* Allocate the secondary action */
1040 new->secondary
= kzalloc(sizeof(struct irqaction
), GFP_KERNEL
);
1041 if (!new->secondary
)
1043 new->secondary
->handler
= irq_forced_secondary_handler
;
1044 new->secondary
->thread_fn
= new->thread_fn
;
1045 new->secondary
->dev_id
= new->dev_id
;
1046 new->secondary
->irq
= new->irq
;
1047 new->secondary
->name
= new->name
;
1049 /* Deal with the primary handler */
1050 set_bit(IRQTF_FORCED_THREAD
, &new->thread_flags
);
1051 new->thread_fn
= new->handler
;
1052 new->handler
= irq_default_primary_handler
;
1056 static int irq_request_resources(struct irq_desc
*desc
)
1058 struct irq_data
*d
= &desc
->irq_data
;
1059 struct irq_chip
*c
= d
->chip
;
1061 return c
->irq_request_resources
? c
->irq_request_resources(d
) : 0;
1064 static void irq_release_resources(struct irq_desc
*desc
)
1066 struct irq_data
*d
= &desc
->irq_data
;
1067 struct irq_chip
*c
= d
->chip
;
1069 if (c
->irq_release_resources
)
1070 c
->irq_release_resources(d
);
1074 setup_irq_thread(struct irqaction
*new, unsigned int irq
, bool secondary
)
1076 struct task_struct
*t
;
1077 struct sched_param param
= {
1078 .sched_priority
= MAX_USER_RT_PRIO
/2,
1082 t
= kthread_create(irq_thread
, new, "irq/%d-%s", irq
,
1085 t
= kthread_create(irq_thread
, new, "irq/%d-s-%s", irq
,
1087 param
.sched_priority
-= 1;
1093 sched_setscheduler_nocheck(t
, SCHED_FIFO
, ¶m
);
1096 * We keep the reference to the task struct even if
1097 * the thread dies to avoid that the interrupt code
1098 * references an already freed task_struct.
1103 * Tell the thread to set its affinity. This is
1104 * important for shared interrupt handlers as we do
1105 * not invoke setup_affinity() for the secondary
1106 * handlers as everything is already set up. Even for
1107 * interrupts marked with IRQF_NO_BALANCE this is
1108 * correct as we want the thread to move to the cpu(s)
1109 * on which the requesting code placed the interrupt.
1111 set_bit(IRQTF_AFFINITY
, &new->thread_flags
);
1116 * Internal function to register an irqaction - typically used to
1117 * allocate special interrupts that are part of the architecture.
1120 __setup_irq(unsigned int irq
, struct irq_desc
*desc
, struct irqaction
*new)
1122 struct irqaction
*old
, **old_ptr
;
1123 unsigned long flags
, thread_mask
= 0;
1124 int ret
, nested
, shared
= 0;
1130 if (desc
->irq_data
.chip
== &no_irq_chip
)
1132 if (!try_module_get(desc
->owner
))
1138 * If the trigger type is not specified by the caller,
1139 * then use the default for this interrupt.
1141 if (!(new->flags
& IRQF_TRIGGER_MASK
))
1142 new->flags
|= irqd_get_trigger_type(&desc
->irq_data
);
1145 * Check whether the interrupt nests into another interrupt
1148 nested
= irq_settings_is_nested_thread(desc
);
1150 if (!new->thread_fn
) {
1155 * Replace the primary handler which was provided from
1156 * the driver for non nested interrupt handling by the
1157 * dummy function which warns when called.
1159 new->handler
= irq_nested_primary_handler
;
1161 if (irq_settings_can_thread(desc
)) {
1162 ret
= irq_setup_forced_threading(new);
1169 * Create a handler thread when a thread function is supplied
1170 * and the interrupt does not nest into another interrupt
1173 if (new->thread_fn
&& !nested
) {
1174 ret
= setup_irq_thread(new, irq
, false);
1177 if (new->secondary
) {
1178 ret
= setup_irq_thread(new->secondary
, irq
, true);
1184 if (!alloc_cpumask_var(&mask
, GFP_KERNEL
)) {
1190 * Drivers are often written to work w/o knowledge about the
1191 * underlying irq chip implementation, so a request for a
1192 * threaded irq without a primary hard irq context handler
1193 * requires the ONESHOT flag to be set. Some irq chips like
1194 * MSI based interrupts are per se one shot safe. Check the
1195 * chip flags, so we can avoid the unmask dance at the end of
1196 * the threaded handler for those.
1198 if (desc
->irq_data
.chip
->flags
& IRQCHIP_ONESHOT_SAFE
)
1199 new->flags
&= ~IRQF_ONESHOT
;
1202 * The following block of code has to be executed atomically
1204 raw_spin_lock_irqsave(&desc
->lock
, flags
);
1205 old_ptr
= &desc
->action
;
1209 * Can't share interrupts unless both agree to and are
1210 * the same type (level, edge, polarity). So both flag
1211 * fields must have IRQF_SHARED set and the bits which
1212 * set the trigger type must match. Also all must
1215 if (!((old
->flags
& new->flags
) & IRQF_SHARED
) ||
1216 ((old
->flags
^ new->flags
) & IRQF_TRIGGER_MASK
) ||
1217 ((old
->flags
^ new->flags
) & IRQF_ONESHOT
))
1220 /* All handlers must agree on per-cpuness */
1221 if ((old
->flags
& IRQF_PERCPU
) !=
1222 (new->flags
& IRQF_PERCPU
))
1225 /* add new interrupt at end of irq queue */
1228 * Or all existing action->thread_mask bits,
1229 * so we can find the next zero bit for this
1232 thread_mask
|= old
->thread_mask
;
1233 old_ptr
= &old
->next
;
1240 * Setup the thread mask for this irqaction for ONESHOT. For
1241 * !ONESHOT irqs the thread mask is 0 so we can avoid a
1242 * conditional in irq_wake_thread().
1244 if (new->flags
& IRQF_ONESHOT
) {
1246 * Unlikely to have 32 resp 64 irqs sharing one line,
1249 if (thread_mask
== ~0UL) {
1254 * The thread_mask for the action is or'ed to
1255 * desc->thread_active to indicate that the
1256 * IRQF_ONESHOT thread handler has been woken, but not
1257 * yet finished. The bit is cleared when a thread
1258 * completes. When all threads of a shared interrupt
1259 * line have completed desc->threads_active becomes
1260 * zero and the interrupt line is unmasked. See
1261 * handle.c:irq_wake_thread() for further information.
1263 * If no thread is woken by primary (hard irq context)
1264 * interrupt handlers, then desc->threads_active is
1265 * also checked for zero to unmask the irq line in the
1266 * affected hard irq flow handlers
1267 * (handle_[fasteoi|level]_irq).
1269 * The new action gets the first zero bit of
1270 * thread_mask assigned. See the loop above which or's
1271 * all existing action->thread_mask bits.
1273 new->thread_mask
= 1 << ffz(thread_mask
);
1275 } else if (new->handler
== irq_default_primary_handler
&&
1276 !(desc
->irq_data
.chip
->flags
& IRQCHIP_ONESHOT_SAFE
)) {
1278 * The interrupt was requested with handler = NULL, so
1279 * we use the default primary handler for it. But it
1280 * does not have the oneshot flag set. In combination
1281 * with level interrupts this is deadly, because the
1282 * default primary handler just wakes the thread, then
1283 * the irq lines is reenabled, but the device still
1284 * has the level irq asserted. Rinse and repeat....
1286 * While this works for edge type interrupts, we play
1287 * it safe and reject unconditionally because we can't
1288 * say for sure which type this interrupt really
1289 * has. The type flags are unreliable as the
1290 * underlying chip implementation can override them.
1292 pr_err("Threaded irq requested with handler=NULL and !ONESHOT for irq %d\n",
1299 ret
= irq_request_resources(desc
);
1301 pr_err("Failed to request resources for %s (irq %d) on irqchip %s\n",
1302 new->name
, irq
, desc
->irq_data
.chip
->name
);
1306 init_waitqueue_head(&desc
->wait_for_threads
);
1308 /* Setup the type (level, edge polarity) if configured: */
1309 if (new->flags
& IRQF_TRIGGER_MASK
) {
1310 ret
= __irq_set_trigger(desc
,
1311 new->flags
& IRQF_TRIGGER_MASK
);
1317 desc
->istate
&= ~(IRQS_AUTODETECT
| IRQS_SPURIOUS_DISABLED
| \
1318 IRQS_ONESHOT
| IRQS_WAITING
);
1319 irqd_clear(&desc
->irq_data
, IRQD_IRQ_INPROGRESS
);
1321 if (new->flags
& IRQF_PERCPU
) {
1322 irqd_set(&desc
->irq_data
, IRQD_PER_CPU
);
1323 irq_settings_set_per_cpu(desc
);
1326 if (new->flags
& IRQF_ONESHOT
)
1327 desc
->istate
|= IRQS_ONESHOT
;
1329 if (irq_settings_can_autoenable(desc
))
1330 irq_startup(desc
, true);
1332 /* Undo nested disables: */
1335 /* Exclude IRQ from balancing if requested */
1336 if (new->flags
& IRQF_NOBALANCING
) {
1337 irq_settings_set_no_balancing(desc
);
1338 irqd_set(&desc
->irq_data
, IRQD_NO_BALANCING
);
1341 /* Set default affinity mask once everything is setup */
1342 setup_affinity(desc
, mask
);
1344 } else if (new->flags
& IRQF_TRIGGER_MASK
) {
1345 unsigned int nmsk
= new->flags
& IRQF_TRIGGER_MASK
;
1346 unsigned int omsk
= irqd_get_trigger_type(&desc
->irq_data
);
1349 /* hope the handler works with current trigger mode */
1350 pr_warn("irq %d uses trigger mode %u; requested %u\n",
1356 irq_pm_install_action(desc
, new);
1358 /* Reset broken irq detection when installing new handler */
1359 desc
->irq_count
= 0;
1360 desc
->irqs_unhandled
= 0;
1363 * Check whether we disabled the irq via the spurious handler
1364 * before. Reenable it and give it another chance.
1366 if (shared
&& (desc
->istate
& IRQS_SPURIOUS_DISABLED
)) {
1367 desc
->istate
&= ~IRQS_SPURIOUS_DISABLED
;
1371 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
1374 * Strictly no need to wake it up, but hung_task complains
1375 * when no hard interrupt wakes the thread up.
1378 wake_up_process(new->thread
);
1380 wake_up_process(new->secondary
->thread
);
1382 register_irq_proc(irq
, desc
);
1384 register_handler_proc(irq
, new);
1385 free_cpumask_var(mask
);
1390 if (!(new->flags
& IRQF_PROBE_SHARED
)) {
1391 pr_err("Flags mismatch irq %d. %08x (%s) vs. %08x (%s)\n",
1392 irq
, new->flags
, new->name
, old
->flags
, old
->name
);
1393 #ifdef CONFIG_DEBUG_SHIRQ
1400 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
1401 free_cpumask_var(mask
);
1405 struct task_struct
*t
= new->thread
;
1411 if (new->secondary
&& new->secondary
->thread
) {
1412 struct task_struct
*t
= new->secondary
->thread
;
1414 new->secondary
->thread
= NULL
;
1419 module_put(desc
->owner
);
1424 * setup_irq - setup an interrupt
1425 * @irq: Interrupt line to setup
1426 * @act: irqaction for the interrupt
1428 * Used to statically setup interrupts in the early boot process.
1430 int setup_irq(unsigned int irq
, struct irqaction
*act
)
1433 struct irq_desc
*desc
= irq_to_desc(irq
);
1435 if (!desc
|| WARN_ON(irq_settings_is_per_cpu_devid(desc
)))
1438 retval
= irq_chip_pm_get(&desc
->irq_data
);
1442 chip_bus_lock(desc
);
1443 retval
= __setup_irq(irq
, desc
, act
);
1444 chip_bus_sync_unlock(desc
);
1447 irq_chip_pm_put(&desc
->irq_data
);
1451 EXPORT_SYMBOL_GPL(setup_irq
);
1454 * Internal function to unregister an irqaction - used to free
1455 * regular and special interrupts that are part of the architecture.
1457 static struct irqaction
*__free_irq(unsigned int irq
, void *dev_id
)
1459 struct irq_desc
*desc
= irq_to_desc(irq
);
1460 struct irqaction
*action
, **action_ptr
;
1461 unsigned long flags
;
1463 WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq
);
1468 chip_bus_lock(desc
);
1469 raw_spin_lock_irqsave(&desc
->lock
, flags
);
1472 * There can be multiple actions per IRQ descriptor, find the right
1473 * one based on the dev_id:
1475 action_ptr
= &desc
->action
;
1477 action
= *action_ptr
;
1480 WARN(1, "Trying to free already-free IRQ %d\n", irq
);
1481 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
1482 chip_bus_sync_unlock(desc
);
1486 if (action
->dev_id
== dev_id
)
1488 action_ptr
= &action
->next
;
1491 /* Found it - now remove it from the list of entries: */
1492 *action_ptr
= action
->next
;
1494 irq_pm_remove_action(desc
, action
);
1496 /* If this was the last handler, shut down the IRQ line: */
1497 if (!desc
->action
) {
1498 irq_settings_clr_disable_unlazy(desc
);
1500 irq_release_resources(desc
);
1504 /* make sure affinity_hint is cleaned up */
1505 if (WARN_ON_ONCE(desc
->affinity_hint
))
1506 desc
->affinity_hint
= NULL
;
1509 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
1510 chip_bus_sync_unlock(desc
);
1512 unregister_handler_proc(irq
, action
);
1514 /* Make sure it's not being used on another CPU: */
1515 synchronize_irq(irq
);
1517 #ifdef CONFIG_DEBUG_SHIRQ
1519 * It's a shared IRQ -- the driver ought to be prepared for an IRQ
1520 * event to happen even now it's being freed, so let's make sure that
1521 * is so by doing an extra call to the handler ....
1523 * ( We do this after actually deregistering it, to make sure that a
1524 * 'real' IRQ doesn't run in * parallel with our fake. )
1526 if (action
->flags
& IRQF_SHARED
) {
1527 local_irq_save(flags
);
1528 action
->handler(irq
, dev_id
);
1529 local_irq_restore(flags
);
1533 if (action
->thread
) {
1534 kthread_stop(action
->thread
);
1535 put_task_struct(action
->thread
);
1536 if (action
->secondary
&& action
->secondary
->thread
) {
1537 kthread_stop(action
->secondary
->thread
);
1538 put_task_struct(action
->secondary
->thread
);
1542 irq_chip_pm_put(&desc
->irq_data
);
1543 module_put(desc
->owner
);
1544 kfree(action
->secondary
);
1549 * remove_irq - free an interrupt
1550 * @irq: Interrupt line to free
1551 * @act: irqaction for the interrupt
1553 * Used to remove interrupts statically setup by the early boot process.
1555 void remove_irq(unsigned int irq
, struct irqaction
*act
)
1557 struct irq_desc
*desc
= irq_to_desc(irq
);
1559 if (desc
&& !WARN_ON(irq_settings_is_per_cpu_devid(desc
)))
1560 __free_irq(irq
, act
->dev_id
);
1562 EXPORT_SYMBOL_GPL(remove_irq
);
1565 * free_irq - free an interrupt allocated with request_irq
1566 * @irq: Interrupt line to free
1567 * @dev_id: Device identity to free
1569 * Remove an interrupt handler. The handler is removed and if the
1570 * interrupt line is no longer in use by any driver it is disabled.
1571 * On a shared IRQ the caller must ensure the interrupt is disabled
1572 * on the card it drives before calling this function. The function
1573 * does not return until any executing interrupts for this IRQ
1576 * This function must not be called from interrupt context.
1578 void free_irq(unsigned int irq
, void *dev_id
)
1580 struct irq_desc
*desc
= irq_to_desc(irq
);
1582 if (!desc
|| WARN_ON(irq_settings_is_per_cpu_devid(desc
)))
1586 if (WARN_ON(desc
->affinity_notify
))
1587 desc
->affinity_notify
= NULL
;
1590 kfree(__free_irq(irq
, dev_id
));
1592 EXPORT_SYMBOL(free_irq
);
1595 * request_threaded_irq - allocate an interrupt line
1596 * @irq: Interrupt line to allocate
1597 * @handler: Function to be called when the IRQ occurs.
1598 * Primary handler for threaded interrupts
1599 * If NULL and thread_fn != NULL the default
1600 * primary handler is installed
1601 * @thread_fn: Function called from the irq handler thread
1602 * If NULL, no irq thread is created
1603 * @irqflags: Interrupt type flags
1604 * @devname: An ascii name for the claiming device
1605 * @dev_id: A cookie passed back to the handler function
1607 * This call allocates interrupt resources and enables the
1608 * interrupt line and IRQ handling. From the point this
1609 * call is made your handler function may be invoked. Since
1610 * your handler function must clear any interrupt the board
1611 * raises, you must take care both to initialise your hardware
1612 * and to set up the interrupt handler in the right order.
1614 * If you want to set up a threaded irq handler for your device
1615 * then you need to supply @handler and @thread_fn. @handler is
1616 * still called in hard interrupt context and has to check
1617 * whether the interrupt originates from the device. If yes it
1618 * needs to disable the interrupt on the device and return
1619 * IRQ_WAKE_THREAD which will wake up the handler thread and run
1620 * @thread_fn. This split handler design is necessary to support
1621 * shared interrupts.
1623 * Dev_id must be globally unique. Normally the address of the
1624 * device data structure is used as the cookie. Since the handler
1625 * receives this value it makes sense to use it.
1627 * If your interrupt is shared you must pass a non NULL dev_id
1628 * as this is required when freeing the interrupt.
1632 * IRQF_SHARED Interrupt is shared
1633 * IRQF_TRIGGER_* Specify active edge(s) or level
1636 int request_threaded_irq(unsigned int irq
, irq_handler_t handler
,
1637 irq_handler_t thread_fn
, unsigned long irqflags
,
1638 const char *devname
, void *dev_id
)
1640 struct irqaction
*action
;
1641 struct irq_desc
*desc
;
1644 if (irq
== IRQ_NOTCONNECTED
)
1648 * Sanity-check: shared interrupts must pass in a real dev-ID,
1649 * otherwise we'll have trouble later trying to figure out
1650 * which interrupt is which (messes up the interrupt freeing
1653 * Also IRQF_COND_SUSPEND only makes sense for shared interrupts and
1654 * it cannot be set along with IRQF_NO_SUSPEND.
1656 if (((irqflags
& IRQF_SHARED
) && !dev_id
) ||
1657 (!(irqflags
& IRQF_SHARED
) && (irqflags
& IRQF_COND_SUSPEND
)) ||
1658 ((irqflags
& IRQF_NO_SUSPEND
) && (irqflags
& IRQF_COND_SUSPEND
)))
1661 desc
= irq_to_desc(irq
);
1665 if (!irq_settings_can_request(desc
) ||
1666 WARN_ON(irq_settings_is_per_cpu_devid(desc
)))
1672 handler
= irq_default_primary_handler
;
1675 action
= kzalloc(sizeof(struct irqaction
), GFP_KERNEL
);
1679 action
->handler
= handler
;
1680 action
->thread_fn
= thread_fn
;
1681 action
->flags
= irqflags
;
1682 action
->name
= devname
;
1683 action
->dev_id
= dev_id
;
1685 retval
= irq_chip_pm_get(&desc
->irq_data
);
1691 chip_bus_lock(desc
);
1692 retval
= __setup_irq(irq
, desc
, action
);
1693 chip_bus_sync_unlock(desc
);
1696 irq_chip_pm_put(&desc
->irq_data
);
1697 kfree(action
->secondary
);
1701 #ifdef CONFIG_DEBUG_SHIRQ_FIXME
1702 if (!retval
&& (irqflags
& IRQF_SHARED
)) {
1704 * It's a shared IRQ -- the driver ought to be prepared for it
1705 * to happen immediately, so let's make sure....
1706 * We disable the irq to make sure that a 'real' IRQ doesn't
1707 * run in parallel with our fake.
1709 unsigned long flags
;
1712 local_irq_save(flags
);
1714 handler(irq
, dev_id
);
1716 local_irq_restore(flags
);
1722 EXPORT_SYMBOL(request_threaded_irq
);
1725 * request_any_context_irq - allocate an interrupt line
1726 * @irq: Interrupt line to allocate
1727 * @handler: Function to be called when the IRQ occurs.
1728 * Threaded handler for threaded interrupts.
1729 * @flags: Interrupt type flags
1730 * @name: An ascii name for the claiming device
1731 * @dev_id: A cookie passed back to the handler function
1733 * This call allocates interrupt resources and enables the
1734 * interrupt line and IRQ handling. It selects either a
1735 * hardirq or threaded handling method depending on the
1738 * On failure, it returns a negative value. On success,
1739 * it returns either IRQC_IS_HARDIRQ or IRQC_IS_NESTED.
1741 int request_any_context_irq(unsigned int irq
, irq_handler_t handler
,
1742 unsigned long flags
, const char *name
, void *dev_id
)
1744 struct irq_desc
*desc
;
1747 if (irq
== IRQ_NOTCONNECTED
)
1750 desc
= irq_to_desc(irq
);
1754 if (irq_settings_is_nested_thread(desc
)) {
1755 ret
= request_threaded_irq(irq
, NULL
, handler
,
1756 flags
, name
, dev_id
);
1757 return !ret
? IRQC_IS_NESTED
: ret
;
1760 ret
= request_irq(irq
, handler
, flags
, name
, dev_id
);
1761 return !ret
? IRQC_IS_HARDIRQ
: ret
;
1763 EXPORT_SYMBOL_GPL(request_any_context_irq
);
1765 void enable_percpu_irq(unsigned int irq
, unsigned int type
)
1767 unsigned int cpu
= smp_processor_id();
1768 unsigned long flags
;
1769 struct irq_desc
*desc
= irq_get_desc_lock(irq
, &flags
, IRQ_GET_DESC_CHECK_PERCPU
);
1775 * If the trigger type is not specified by the caller, then
1776 * use the default for this interrupt.
1778 type
&= IRQ_TYPE_SENSE_MASK
;
1779 if (type
== IRQ_TYPE_NONE
)
1780 type
= irqd_get_trigger_type(&desc
->irq_data
);
1782 if (type
!= IRQ_TYPE_NONE
) {
1785 ret
= __irq_set_trigger(desc
, type
);
1788 WARN(1, "failed to set type for IRQ%d\n", irq
);
1793 irq_percpu_enable(desc
, cpu
);
1795 irq_put_desc_unlock(desc
, flags
);
1797 EXPORT_SYMBOL_GPL(enable_percpu_irq
);
1800 * irq_percpu_is_enabled - Check whether the per cpu irq is enabled
1801 * @irq: Linux irq number to check for
1803 * Must be called from a non migratable context. Returns the enable
1804 * state of a per cpu interrupt on the current cpu.
1806 bool irq_percpu_is_enabled(unsigned int irq
)
1808 unsigned int cpu
= smp_processor_id();
1809 struct irq_desc
*desc
;
1810 unsigned long flags
;
1813 desc
= irq_get_desc_lock(irq
, &flags
, IRQ_GET_DESC_CHECK_PERCPU
);
1817 is_enabled
= cpumask_test_cpu(cpu
, desc
->percpu_enabled
);
1818 irq_put_desc_unlock(desc
, flags
);
1822 EXPORT_SYMBOL_GPL(irq_percpu_is_enabled
);
1824 void disable_percpu_irq(unsigned int irq
)
1826 unsigned int cpu
= smp_processor_id();
1827 unsigned long flags
;
1828 struct irq_desc
*desc
= irq_get_desc_lock(irq
, &flags
, IRQ_GET_DESC_CHECK_PERCPU
);
1833 irq_percpu_disable(desc
, cpu
);
1834 irq_put_desc_unlock(desc
, flags
);
1836 EXPORT_SYMBOL_GPL(disable_percpu_irq
);
1839 * Internal function to unregister a percpu irqaction.
1841 static struct irqaction
*__free_percpu_irq(unsigned int irq
, void __percpu
*dev_id
)
1843 struct irq_desc
*desc
= irq_to_desc(irq
);
1844 struct irqaction
*action
;
1845 unsigned long flags
;
1847 WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq
);
1852 raw_spin_lock_irqsave(&desc
->lock
, flags
);
1854 action
= desc
->action
;
1855 if (!action
|| action
->percpu_dev_id
!= dev_id
) {
1856 WARN(1, "Trying to free already-free IRQ %d\n", irq
);
1860 if (!cpumask_empty(desc
->percpu_enabled
)) {
1861 WARN(1, "percpu IRQ %d still enabled on CPU%d!\n",
1862 irq
, cpumask_first(desc
->percpu_enabled
));
1866 /* Found it - now remove it from the list of entries: */
1867 desc
->action
= NULL
;
1869 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
1871 unregister_handler_proc(irq
, action
);
1873 irq_chip_pm_put(&desc
->irq_data
);
1874 module_put(desc
->owner
);
1878 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
1883 * remove_percpu_irq - free a per-cpu interrupt
1884 * @irq: Interrupt line to free
1885 * @act: irqaction for the interrupt
1887 * Used to remove interrupts statically setup by the early boot process.
1889 void remove_percpu_irq(unsigned int irq
, struct irqaction
*act
)
1891 struct irq_desc
*desc
= irq_to_desc(irq
);
1893 if (desc
&& irq_settings_is_per_cpu_devid(desc
))
1894 __free_percpu_irq(irq
, act
->percpu_dev_id
);
1898 * free_percpu_irq - free an interrupt allocated with request_percpu_irq
1899 * @irq: Interrupt line to free
1900 * @dev_id: Device identity to free
1902 * Remove a percpu interrupt handler. The handler is removed, but
1903 * the interrupt line is not disabled. This must be done on each
1904 * CPU before calling this function. The function does not return
1905 * until any executing interrupts for this IRQ have completed.
1907 * This function must not be called from interrupt context.
1909 void free_percpu_irq(unsigned int irq
, void __percpu
*dev_id
)
1911 struct irq_desc
*desc
= irq_to_desc(irq
);
1913 if (!desc
|| !irq_settings_is_per_cpu_devid(desc
))
1916 chip_bus_lock(desc
);
1917 kfree(__free_percpu_irq(irq
, dev_id
));
1918 chip_bus_sync_unlock(desc
);
1920 EXPORT_SYMBOL_GPL(free_percpu_irq
);
1923 * setup_percpu_irq - setup a per-cpu interrupt
1924 * @irq: Interrupt line to setup
1925 * @act: irqaction for the interrupt
1927 * Used to statically setup per-cpu interrupts in the early boot process.
1929 int setup_percpu_irq(unsigned int irq
, struct irqaction
*act
)
1931 struct irq_desc
*desc
= irq_to_desc(irq
);
1934 if (!desc
|| !irq_settings_is_per_cpu_devid(desc
))
1937 retval
= irq_chip_pm_get(&desc
->irq_data
);
1941 chip_bus_lock(desc
);
1942 retval
= __setup_irq(irq
, desc
, act
);
1943 chip_bus_sync_unlock(desc
);
1946 irq_chip_pm_put(&desc
->irq_data
);
1952 * request_percpu_irq - allocate a percpu interrupt line
1953 * @irq: Interrupt line to allocate
1954 * @handler: Function to be called when the IRQ occurs.
1955 * @devname: An ascii name for the claiming device
1956 * @dev_id: A percpu cookie passed back to the handler function
1958 * This call allocates interrupt resources and enables the
1959 * interrupt on the local CPU. If the interrupt is supposed to be
1960 * enabled on other CPUs, it has to be done on each CPU using
1961 * enable_percpu_irq().
1963 * Dev_id must be globally unique. It is a per-cpu variable, and
1964 * the handler gets called with the interrupted CPU's instance of
1967 int request_percpu_irq(unsigned int irq
, irq_handler_t handler
,
1968 const char *devname
, void __percpu
*dev_id
)
1970 struct irqaction
*action
;
1971 struct irq_desc
*desc
;
1977 desc
= irq_to_desc(irq
);
1978 if (!desc
|| !irq_settings_can_request(desc
) ||
1979 !irq_settings_is_per_cpu_devid(desc
))
1982 action
= kzalloc(sizeof(struct irqaction
), GFP_KERNEL
);
1986 action
->handler
= handler
;
1987 action
->flags
= IRQF_PERCPU
| IRQF_NO_SUSPEND
;
1988 action
->name
= devname
;
1989 action
->percpu_dev_id
= dev_id
;
1991 retval
= irq_chip_pm_get(&desc
->irq_data
);
1997 chip_bus_lock(desc
);
1998 retval
= __setup_irq(irq
, desc
, action
);
1999 chip_bus_sync_unlock(desc
);
2002 irq_chip_pm_put(&desc
->irq_data
);
2008 EXPORT_SYMBOL_GPL(request_percpu_irq
);
2011 * irq_get_irqchip_state - returns the irqchip state of a interrupt.
2012 * @irq: Interrupt line that is forwarded to a VM
2013 * @which: One of IRQCHIP_STATE_* the caller wants to know about
2014 * @state: a pointer to a boolean where the state is to be storeed
2016 * This call snapshots the internal irqchip state of an
2017 * interrupt, returning into @state the bit corresponding to
2020 * This function should be called with preemption disabled if the
2021 * interrupt controller has per-cpu registers.
2023 int irq_get_irqchip_state(unsigned int irq
, enum irqchip_irq_state which
,
2026 struct irq_desc
*desc
;
2027 struct irq_data
*data
;
2028 struct irq_chip
*chip
;
2029 unsigned long flags
;
2032 desc
= irq_get_desc_buslock(irq
, &flags
, 0);
2036 data
= irq_desc_get_irq_data(desc
);
2039 chip
= irq_data_get_irq_chip(data
);
2040 if (chip
->irq_get_irqchip_state
)
2042 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
2043 data
= data
->parent_data
;
2050 err
= chip
->irq_get_irqchip_state(data
, which
, state
);
2052 irq_put_desc_busunlock(desc
, flags
);
2055 EXPORT_SYMBOL_GPL(irq_get_irqchip_state
);
2058 * irq_set_irqchip_state - set the state of a forwarded interrupt.
2059 * @irq: Interrupt line that is forwarded to a VM
2060 * @which: State to be restored (one of IRQCHIP_STATE_*)
2061 * @val: Value corresponding to @which
2063 * This call sets the internal irqchip state of an interrupt,
2064 * depending on the value of @which.
2066 * This function should be called with preemption disabled if the
2067 * interrupt controller has per-cpu registers.
2069 int irq_set_irqchip_state(unsigned int irq
, enum irqchip_irq_state which
,
2072 struct irq_desc
*desc
;
2073 struct irq_data
*data
;
2074 struct irq_chip
*chip
;
2075 unsigned long flags
;
2078 desc
= irq_get_desc_buslock(irq
, &flags
, 0);
2082 data
= irq_desc_get_irq_data(desc
);
2085 chip
= irq_data_get_irq_chip(data
);
2086 if (chip
->irq_set_irqchip_state
)
2088 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
2089 data
= data
->parent_data
;
2096 err
= chip
->irq_set_irqchip_state(data
, which
, val
);
2098 irq_put_desc_busunlock(desc
, flags
);
2101 EXPORT_SYMBOL_GPL(irq_set_irqchip_state
);