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 int __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_set_thread_affinity - Notify irq threads to adjust affinity
138 * @desc: irq descriptor which has affitnity changed
140 * We just set IRQTF_AFFINITY and delegate the affinity setting
141 * to the interrupt thread itself. We can not call
142 * set_cpus_allowed_ptr() here as we hold desc->lock and this
143 * code can be called from hard interrupt context.
145 void irq_set_thread_affinity(struct irq_desc
*desc
)
147 struct irqaction
*action
= desc
->action
;
151 set_bit(IRQTF_AFFINITY
, &action
->thread_flags
);
152 action
= action
->next
;
156 #ifdef CONFIG_GENERIC_PENDING_IRQ
157 static inline bool irq_can_move_pcntxt(struct irq_data
*data
)
159 return irqd_can_move_in_process_context(data
);
161 static inline bool irq_move_pending(struct irq_data
*data
)
163 return irqd_is_setaffinity_pending(data
);
166 irq_copy_pending(struct irq_desc
*desc
, const struct cpumask
*mask
)
168 cpumask_copy(desc
->pending_mask
, mask
);
171 irq_get_pending(struct cpumask
*mask
, struct irq_desc
*desc
)
173 cpumask_copy(mask
, desc
->pending_mask
);
176 static inline bool irq_can_move_pcntxt(struct irq_data
*data
) { return true; }
177 static inline bool irq_move_pending(struct irq_data
*data
) { return false; }
179 irq_copy_pending(struct irq_desc
*desc
, const struct cpumask
*mask
) { }
181 irq_get_pending(struct cpumask
*mask
, struct irq_desc
*desc
) { }
184 int irq_do_set_affinity(struct irq_data
*data
, const struct cpumask
*mask
,
187 struct irq_desc
*desc
= irq_data_to_desc(data
);
188 struct irq_chip
*chip
= irq_data_get_irq_chip(data
);
191 ret
= chip
->irq_set_affinity(data
, mask
, force
);
193 case IRQ_SET_MASK_OK
:
194 case IRQ_SET_MASK_OK_DONE
:
195 cpumask_copy(data
->affinity
, mask
);
196 case IRQ_SET_MASK_OK_NOCOPY
:
197 irq_set_thread_affinity(desc
);
204 int irq_set_affinity_locked(struct irq_data
*data
, const struct cpumask
*mask
,
207 struct irq_chip
*chip
= irq_data_get_irq_chip(data
);
208 struct irq_desc
*desc
= irq_data_to_desc(data
);
211 if (!chip
|| !chip
->irq_set_affinity
)
214 if (irq_can_move_pcntxt(data
)) {
215 ret
= irq_do_set_affinity(data
, mask
, force
);
217 irqd_set_move_pending(data
);
218 irq_copy_pending(desc
, mask
);
221 if (desc
->affinity_notify
) {
222 kref_get(&desc
->affinity_notify
->kref
);
223 schedule_work(&desc
->affinity_notify
->work
);
225 irqd_set(data
, IRQD_AFFINITY_SET
);
230 int __irq_set_affinity(unsigned int irq
, const struct cpumask
*mask
, bool force
)
232 struct irq_desc
*desc
= irq_to_desc(irq
);
239 raw_spin_lock_irqsave(&desc
->lock
, flags
);
240 ret
= irq_set_affinity_locked(irq_desc_get_irq_data(desc
), mask
, force
);
241 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
245 int irq_set_affinity_hint(unsigned int irq
, const struct cpumask
*m
)
248 struct irq_desc
*desc
= irq_get_desc_lock(irq
, &flags
, IRQ_GET_DESC_CHECK_GLOBAL
);
252 desc
->affinity_hint
= m
;
253 irq_put_desc_unlock(desc
, flags
);
254 /* set the initial affinity to prevent every interrupt being on CPU0 */
256 __irq_set_affinity(irq
, m
, false);
259 EXPORT_SYMBOL_GPL(irq_set_affinity_hint
);
262 * irq_set_vcpu_affinity - Set vcpu affinity for the interrupt
263 * @irq: interrupt number to set affinity
264 * @vcpu_info: vCPU specific data
266 * This function uses the vCPU specific data to set the vCPU
267 * affinity for an irq. The vCPU specific data is passed from
268 * outside, such as KVM. One example code path is as below:
269 * KVM -> IOMMU -> irq_set_vcpu_affinity().
271 int irq_set_vcpu_affinity(unsigned int irq
, void *vcpu_info
)
274 struct irq_desc
*desc
= irq_get_desc_lock(irq
, &flags
, 0);
275 struct irq_data
*data
;
276 struct irq_chip
*chip
;
282 data
= irq_desc_get_irq_data(desc
);
283 chip
= irq_data_get_irq_chip(data
);
284 if (chip
&& chip
->irq_set_vcpu_affinity
)
285 ret
= chip
->irq_set_vcpu_affinity(data
, vcpu_info
);
286 irq_put_desc_unlock(desc
, flags
);
290 EXPORT_SYMBOL_GPL(irq_set_vcpu_affinity
);
292 static void irq_affinity_notify(struct work_struct
*work
)
294 struct irq_affinity_notify
*notify
=
295 container_of(work
, struct irq_affinity_notify
, work
);
296 struct irq_desc
*desc
= irq_to_desc(notify
->irq
);
297 cpumask_var_t cpumask
;
300 if (!desc
|| !alloc_cpumask_var(&cpumask
, GFP_KERNEL
))
303 raw_spin_lock_irqsave(&desc
->lock
, flags
);
304 if (irq_move_pending(&desc
->irq_data
))
305 irq_get_pending(cpumask
, desc
);
307 cpumask_copy(cpumask
, desc
->irq_data
.affinity
);
308 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
310 notify
->notify(notify
, cpumask
);
312 free_cpumask_var(cpumask
);
314 kref_put(¬ify
->kref
, notify
->release
);
318 * irq_set_affinity_notifier - control notification of IRQ affinity changes
319 * @irq: Interrupt for which to enable/disable notification
320 * @notify: Context for notification, or %NULL to disable
321 * notification. Function pointers must be initialised;
322 * the other fields will be initialised by this function.
324 * Must be called in process context. Notification may only be enabled
325 * after the IRQ is allocated and must be disabled before the IRQ is
326 * freed using free_irq().
329 irq_set_affinity_notifier(unsigned int irq
, struct irq_affinity_notify
*notify
)
331 struct irq_desc
*desc
= irq_to_desc(irq
);
332 struct irq_affinity_notify
*old_notify
;
335 /* The release function is promised process context */
341 /* Complete initialisation of *notify */
344 kref_init(¬ify
->kref
);
345 INIT_WORK(¬ify
->work
, irq_affinity_notify
);
348 raw_spin_lock_irqsave(&desc
->lock
, flags
);
349 old_notify
= desc
->affinity_notify
;
350 desc
->affinity_notify
= notify
;
351 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
354 kref_put(&old_notify
->kref
, old_notify
->release
);
358 EXPORT_SYMBOL_GPL(irq_set_affinity_notifier
);
360 #ifndef CONFIG_AUTO_IRQ_AFFINITY
362 * Generic version of the affinity autoselector.
364 static int setup_affinity(struct irq_desc
*desc
, struct cpumask
*mask
)
366 struct cpumask
*set
= irq_default_affinity
;
367 int node
= irq_desc_get_node(desc
);
369 /* Excludes PER_CPU and NO_BALANCE interrupts */
370 if (!__irq_can_set_affinity(desc
))
374 * Preserve an userspace affinity setup, but make sure that
375 * one of the targets is online.
377 if (irqd_has_set(&desc
->irq_data
, IRQD_AFFINITY_SET
)) {
378 if (cpumask_intersects(desc
->irq_data
.affinity
,
380 set
= desc
->irq_data
.affinity
;
382 irqd_clear(&desc
->irq_data
, IRQD_AFFINITY_SET
);
385 cpumask_and(mask
, cpu_online_mask
, set
);
386 if (node
!= NUMA_NO_NODE
) {
387 const struct cpumask
*nodemask
= cpumask_of_node(node
);
389 /* make sure at least one of the cpus in nodemask is online */
390 if (cpumask_intersects(mask
, nodemask
))
391 cpumask_and(mask
, mask
, nodemask
);
393 irq_do_set_affinity(&desc
->irq_data
, mask
, false);
397 /* Wrapper for ALPHA specific affinity selector magic */
398 static inline int setup_affinity(struct irq_desc
*d
, struct cpumask
*mask
)
400 return irq_select_affinity(irq_desc_get_irq(d
));
405 * Called when affinity is set via /proc/irq
407 int irq_select_affinity_usr(unsigned int irq
, struct cpumask
*mask
)
409 struct irq_desc
*desc
= irq_to_desc(irq
);
413 raw_spin_lock_irqsave(&desc
->lock
, flags
);
414 ret
= setup_affinity(desc
, mask
);
415 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
421 setup_affinity(struct irq_desc
*desc
, struct cpumask
*mask
)
427 void __disable_irq(struct irq_desc
*desc
)
433 static int __disable_irq_nosync(unsigned int irq
)
436 struct irq_desc
*desc
= irq_get_desc_buslock(irq
, &flags
, IRQ_GET_DESC_CHECK_GLOBAL
);
441 irq_put_desc_busunlock(desc
, flags
);
446 * disable_irq_nosync - disable an irq without waiting
447 * @irq: Interrupt to disable
449 * Disable the selected interrupt line. Disables and Enables are
451 * Unlike disable_irq(), this function does not ensure existing
452 * instances of the IRQ handler have completed before returning.
454 * This function may be called from IRQ context.
456 void disable_irq_nosync(unsigned int irq
)
458 __disable_irq_nosync(irq
);
460 EXPORT_SYMBOL(disable_irq_nosync
);
463 * disable_irq - disable an irq and wait for completion
464 * @irq: Interrupt to disable
466 * Disable the selected interrupt line. Enables and Disables are
468 * This function waits for any pending IRQ handlers for this interrupt
469 * to complete before returning. If you use this function while
470 * holding a resource the IRQ handler may need you will deadlock.
472 * This function may be called - with care - from IRQ context.
474 void disable_irq(unsigned int irq
)
476 if (!__disable_irq_nosync(irq
))
477 synchronize_irq(irq
);
479 EXPORT_SYMBOL(disable_irq
);
482 * disable_hardirq - disables an irq and waits for hardirq completion
483 * @irq: Interrupt to disable
485 * Disable the selected interrupt line. Enables and Disables are
487 * This function waits for any pending hard IRQ handlers for this
488 * interrupt to complete before returning. If you use this function while
489 * holding a resource the hard IRQ handler may need you will deadlock.
491 * When used to optimistically disable an interrupt from atomic context
492 * the return value must be checked.
494 * Returns: false if a threaded handler is active.
496 * This function may be called - with care - from IRQ context.
498 bool disable_hardirq(unsigned int irq
)
500 if (!__disable_irq_nosync(irq
))
501 return synchronize_hardirq(irq
);
505 EXPORT_SYMBOL_GPL(disable_hardirq
);
507 void __enable_irq(struct irq_desc
*desc
)
509 switch (desc
->depth
) {
512 WARN(1, KERN_WARNING
"Unbalanced enable for IRQ %d\n",
513 irq_desc_get_irq(desc
));
516 if (desc
->istate
& IRQS_SUSPENDED
)
518 /* Prevent probing on this irq: */
519 irq_settings_set_noprobe(desc
);
521 check_irq_resend(desc
);
530 * enable_irq - enable handling of an irq
531 * @irq: Interrupt to enable
533 * Undoes the effect of one call to disable_irq(). If this
534 * matches the last disable, processing of interrupts on this
535 * IRQ line is re-enabled.
537 * This function may be called from IRQ context only when
538 * desc->irq_data.chip->bus_lock and desc->chip->bus_sync_unlock are NULL !
540 void enable_irq(unsigned int irq
)
543 struct irq_desc
*desc
= irq_get_desc_buslock(irq
, &flags
, IRQ_GET_DESC_CHECK_GLOBAL
);
547 if (WARN(!desc
->irq_data
.chip
,
548 KERN_ERR
"enable_irq before setup/request_irq: irq %u\n", irq
))
553 irq_put_desc_busunlock(desc
, flags
);
555 EXPORT_SYMBOL(enable_irq
);
557 static int set_irq_wake_real(unsigned int irq
, unsigned int on
)
559 struct irq_desc
*desc
= irq_to_desc(irq
);
562 if (irq_desc_get_chip(desc
)->flags
& IRQCHIP_SKIP_SET_WAKE
)
565 if (desc
->irq_data
.chip
->irq_set_wake
)
566 ret
= desc
->irq_data
.chip
->irq_set_wake(&desc
->irq_data
, on
);
572 * irq_set_irq_wake - control irq power management wakeup
573 * @irq: interrupt to control
574 * @on: enable/disable power management wakeup
576 * Enable/disable power management wakeup mode, which is
577 * disabled by default. Enables and disables must match,
578 * just as they match for non-wakeup mode support.
580 * Wakeup mode lets this IRQ wake the system from sleep
581 * states like "suspend to RAM".
583 int irq_set_irq_wake(unsigned int irq
, unsigned int on
)
586 struct irq_desc
*desc
= irq_get_desc_buslock(irq
, &flags
, IRQ_GET_DESC_CHECK_GLOBAL
);
592 /* wakeup-capable irqs can be shared between drivers that
593 * don't need to have the same sleep mode behaviors.
596 if (desc
->wake_depth
++ == 0) {
597 ret
= set_irq_wake_real(irq
, on
);
599 desc
->wake_depth
= 0;
601 irqd_set(&desc
->irq_data
, IRQD_WAKEUP_STATE
);
604 if (desc
->wake_depth
== 0) {
605 WARN(1, "Unbalanced IRQ %d wake disable\n", irq
);
606 } else if (--desc
->wake_depth
== 0) {
607 ret
= set_irq_wake_real(irq
, on
);
609 desc
->wake_depth
= 1;
611 irqd_clear(&desc
->irq_data
, IRQD_WAKEUP_STATE
);
614 irq_put_desc_busunlock(desc
, flags
);
617 EXPORT_SYMBOL(irq_set_irq_wake
);
620 * Internal function that tells the architecture code whether a
621 * particular irq has been exclusively allocated or is available
624 int can_request_irq(unsigned int irq
, unsigned long irqflags
)
627 struct irq_desc
*desc
= irq_get_desc_lock(irq
, &flags
, 0);
633 if (irq_settings_can_request(desc
)) {
635 irqflags
& desc
->action
->flags
& IRQF_SHARED
)
638 irq_put_desc_unlock(desc
, flags
);
642 int __irq_set_trigger(struct irq_desc
*desc
, unsigned long flags
)
644 struct irq_chip
*chip
= desc
->irq_data
.chip
;
647 if (!chip
|| !chip
->irq_set_type
) {
649 * IRQF_TRIGGER_* but the PIC does not support multiple
652 pr_debug("No set_type function for IRQ %d (%s)\n",
653 irq_desc_get_irq(desc
),
654 chip
? (chip
->name
? : "unknown") : "unknown");
658 flags
&= IRQ_TYPE_SENSE_MASK
;
660 if (chip
->flags
& IRQCHIP_SET_TYPE_MASKED
) {
661 if (!irqd_irq_masked(&desc
->irq_data
))
663 if (!irqd_irq_disabled(&desc
->irq_data
))
667 /* caller masked out all except trigger mode flags */
668 ret
= chip
->irq_set_type(&desc
->irq_data
, flags
);
671 case IRQ_SET_MASK_OK
:
672 case IRQ_SET_MASK_OK_DONE
:
673 irqd_clear(&desc
->irq_data
, IRQD_TRIGGER_MASK
);
674 irqd_set(&desc
->irq_data
, flags
);
676 case IRQ_SET_MASK_OK_NOCOPY
:
677 flags
= irqd_get_trigger_type(&desc
->irq_data
);
678 irq_settings_set_trigger_mask(desc
, flags
);
679 irqd_clear(&desc
->irq_data
, IRQD_LEVEL
);
680 irq_settings_clr_level(desc
);
681 if (flags
& IRQ_TYPE_LEVEL_MASK
) {
682 irq_settings_set_level(desc
);
683 irqd_set(&desc
->irq_data
, IRQD_LEVEL
);
689 pr_err("Setting trigger mode %lu for irq %u failed (%pF)\n",
690 flags
, irq_desc_get_irq(desc
), chip
->irq_set_type
);
697 #ifdef CONFIG_HARDIRQS_SW_RESEND
698 int irq_set_parent(int irq
, int parent_irq
)
701 struct irq_desc
*desc
= irq_get_desc_lock(irq
, &flags
, 0);
706 desc
->parent_irq
= parent_irq
;
708 irq_put_desc_unlock(desc
, flags
);
714 * Default primary interrupt handler for threaded interrupts. Is
715 * assigned as primary handler when request_threaded_irq is called
716 * with handler == NULL. Useful for oneshot interrupts.
718 static irqreturn_t
irq_default_primary_handler(int irq
, void *dev_id
)
720 return IRQ_WAKE_THREAD
;
724 * Primary handler for nested threaded interrupts. Should never be
727 static irqreturn_t
irq_nested_primary_handler(int irq
, void *dev_id
)
729 WARN(1, "Primary handler called for nested irq %d\n", irq
);
733 static int irq_wait_for_interrupt(struct irqaction
*action
)
735 set_current_state(TASK_INTERRUPTIBLE
);
737 while (!kthread_should_stop()) {
739 if (test_and_clear_bit(IRQTF_RUNTHREAD
,
740 &action
->thread_flags
)) {
741 __set_current_state(TASK_RUNNING
);
745 set_current_state(TASK_INTERRUPTIBLE
);
747 __set_current_state(TASK_RUNNING
);
752 * Oneshot interrupts keep the irq line masked until the threaded
753 * handler finished. unmask if the interrupt has not been disabled and
756 static void irq_finalize_oneshot(struct irq_desc
*desc
,
757 struct irqaction
*action
)
759 if (!(desc
->istate
& IRQS_ONESHOT
))
763 raw_spin_lock_irq(&desc
->lock
);
766 * Implausible though it may be we need to protect us against
767 * the following scenario:
769 * The thread is faster done than the hard interrupt handler
770 * on the other CPU. If we unmask the irq line then the
771 * interrupt can come in again and masks the line, leaves due
772 * to IRQS_INPROGRESS and the irq line is masked forever.
774 * This also serializes the state of shared oneshot handlers
775 * versus "desc->threads_onehsot |= action->thread_mask;" in
776 * irq_wake_thread(). See the comment there which explains the
779 if (unlikely(irqd_irq_inprogress(&desc
->irq_data
))) {
780 raw_spin_unlock_irq(&desc
->lock
);
781 chip_bus_sync_unlock(desc
);
787 * Now check again, whether the thread should run. Otherwise
788 * we would clear the threads_oneshot bit of this thread which
791 if (test_bit(IRQTF_RUNTHREAD
, &action
->thread_flags
))
794 desc
->threads_oneshot
&= ~action
->thread_mask
;
796 if (!desc
->threads_oneshot
&& !irqd_irq_disabled(&desc
->irq_data
) &&
797 irqd_irq_masked(&desc
->irq_data
))
798 unmask_threaded_irq(desc
);
801 raw_spin_unlock_irq(&desc
->lock
);
802 chip_bus_sync_unlock(desc
);
807 * Check whether we need to change the affinity of the interrupt thread.
810 irq_thread_check_affinity(struct irq_desc
*desc
, struct irqaction
*action
)
815 if (!test_and_clear_bit(IRQTF_AFFINITY
, &action
->thread_flags
))
819 * In case we are out of memory we set IRQTF_AFFINITY again and
820 * try again next time
822 if (!alloc_cpumask_var(&mask
, GFP_KERNEL
)) {
823 set_bit(IRQTF_AFFINITY
, &action
->thread_flags
);
827 raw_spin_lock_irq(&desc
->lock
);
829 * This code is triggered unconditionally. Check the affinity
830 * mask pointer. For CPU_MASK_OFFSTACK=n this is optimized out.
832 if (desc
->irq_data
.affinity
)
833 cpumask_copy(mask
, desc
->irq_data
.affinity
);
836 raw_spin_unlock_irq(&desc
->lock
);
839 set_cpus_allowed_ptr(current
, mask
);
840 free_cpumask_var(mask
);
844 irq_thread_check_affinity(struct irq_desc
*desc
, struct irqaction
*action
) { }
848 * Interrupts which are not explicitely requested as threaded
849 * interrupts rely on the implicit bh/preempt disable of the hard irq
850 * context. So we need to disable bh here to avoid deadlocks and other
854 irq_forced_thread_fn(struct irq_desc
*desc
, struct irqaction
*action
)
859 ret
= action
->thread_fn(action
->irq
, action
->dev_id
);
860 irq_finalize_oneshot(desc
, action
);
866 * Interrupts explicitly requested as threaded interrupts want to be
867 * preemtible - many of them need to sleep and wait for slow busses to
870 static irqreturn_t
irq_thread_fn(struct irq_desc
*desc
,
871 struct irqaction
*action
)
875 ret
= action
->thread_fn(action
->irq
, action
->dev_id
);
876 irq_finalize_oneshot(desc
, action
);
880 static void wake_threads_waitq(struct irq_desc
*desc
)
882 if (atomic_dec_and_test(&desc
->threads_active
))
883 wake_up(&desc
->wait_for_threads
);
886 static void irq_thread_dtor(struct callback_head
*unused
)
888 struct task_struct
*tsk
= current
;
889 struct irq_desc
*desc
;
890 struct irqaction
*action
;
892 if (WARN_ON_ONCE(!(current
->flags
& PF_EXITING
)))
895 action
= kthread_data(tsk
);
897 pr_err("exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n",
898 tsk
->comm
, tsk
->pid
, action
->irq
);
901 desc
= irq_to_desc(action
->irq
);
903 * If IRQTF_RUNTHREAD is set, we need to decrement
904 * desc->threads_active and wake possible waiters.
906 if (test_and_clear_bit(IRQTF_RUNTHREAD
, &action
->thread_flags
))
907 wake_threads_waitq(desc
);
909 /* Prevent a stale desc->threads_oneshot */
910 irq_finalize_oneshot(desc
, action
);
914 * Interrupt handler thread
916 static int irq_thread(void *data
)
918 struct callback_head on_exit_work
;
919 struct irqaction
*action
= data
;
920 struct irq_desc
*desc
= irq_to_desc(action
->irq
);
921 irqreturn_t (*handler_fn
)(struct irq_desc
*desc
,
922 struct irqaction
*action
);
924 if (force_irqthreads
&& test_bit(IRQTF_FORCED_THREAD
,
925 &action
->thread_flags
))
926 handler_fn
= irq_forced_thread_fn
;
928 handler_fn
= irq_thread_fn
;
930 init_task_work(&on_exit_work
, irq_thread_dtor
);
931 task_work_add(current
, &on_exit_work
, false);
933 irq_thread_check_affinity(desc
, action
);
935 while (!irq_wait_for_interrupt(action
)) {
936 irqreturn_t action_ret
;
938 irq_thread_check_affinity(desc
, action
);
940 action_ret
= handler_fn(desc
, action
);
941 if (action_ret
== IRQ_HANDLED
)
942 atomic_inc(&desc
->threads_handled
);
944 wake_threads_waitq(desc
);
948 * This is the regular exit path. __free_irq() is stopping the
949 * thread via kthread_stop() after calling
950 * synchronize_irq(). So neither IRQTF_RUNTHREAD nor the
951 * oneshot mask bit can be set. We cannot verify that as we
952 * cannot touch the oneshot mask at this point anymore as
953 * __setup_irq() might have given out currents thread_mask
956 task_work_cancel(current
, irq_thread_dtor
);
961 * irq_wake_thread - wake the irq thread for the action identified by dev_id
962 * @irq: Interrupt line
963 * @dev_id: Device identity for which the thread should be woken
966 void irq_wake_thread(unsigned int irq
, void *dev_id
)
968 struct irq_desc
*desc
= irq_to_desc(irq
);
969 struct irqaction
*action
;
972 if (!desc
|| WARN_ON(irq_settings_is_per_cpu_devid(desc
)))
975 raw_spin_lock_irqsave(&desc
->lock
, flags
);
976 for (action
= desc
->action
; action
; action
= action
->next
) {
977 if (action
->dev_id
== dev_id
) {
979 __irq_wake_thread(desc
, action
);
983 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
985 EXPORT_SYMBOL_GPL(irq_wake_thread
);
987 static void irq_setup_forced_threading(struct irqaction
*new)
989 if (!force_irqthreads
)
991 if (new->flags
& (IRQF_NO_THREAD
| IRQF_PERCPU
| IRQF_ONESHOT
))
994 new->flags
|= IRQF_ONESHOT
;
996 if (!new->thread_fn
) {
997 set_bit(IRQTF_FORCED_THREAD
, &new->thread_flags
);
998 new->thread_fn
= new->handler
;
999 new->handler
= irq_default_primary_handler
;
1003 static int irq_request_resources(struct irq_desc
*desc
)
1005 struct irq_data
*d
= &desc
->irq_data
;
1006 struct irq_chip
*c
= d
->chip
;
1008 return c
->irq_request_resources
? c
->irq_request_resources(d
) : 0;
1011 static void irq_release_resources(struct irq_desc
*desc
)
1013 struct irq_data
*d
= &desc
->irq_data
;
1014 struct irq_chip
*c
= d
->chip
;
1016 if (c
->irq_release_resources
)
1017 c
->irq_release_resources(d
);
1021 * Internal function to register an irqaction - typically used to
1022 * allocate special interrupts that are part of the architecture.
1025 __setup_irq(unsigned int irq
, struct irq_desc
*desc
, struct irqaction
*new)
1027 struct irqaction
*old
, **old_ptr
;
1028 unsigned long flags
, thread_mask
= 0;
1029 int ret
, nested
, shared
= 0;
1035 if (desc
->irq_data
.chip
== &no_irq_chip
)
1037 if (!try_module_get(desc
->owner
))
1041 * Check whether the interrupt nests into another interrupt
1044 nested
= irq_settings_is_nested_thread(desc
);
1046 if (!new->thread_fn
) {
1051 * Replace the primary handler which was provided from
1052 * the driver for non nested interrupt handling by the
1053 * dummy function which warns when called.
1055 new->handler
= irq_nested_primary_handler
;
1057 if (irq_settings_can_thread(desc
))
1058 irq_setup_forced_threading(new);
1062 * Create a handler thread when a thread function is supplied
1063 * and the interrupt does not nest into another interrupt
1066 if (new->thread_fn
&& !nested
) {
1067 struct task_struct
*t
;
1068 static const struct sched_param param
= {
1069 .sched_priority
= MAX_USER_RT_PRIO
/2,
1072 t
= kthread_create(irq_thread
, new, "irq/%d-%s", irq
,
1079 sched_setscheduler_nocheck(t
, SCHED_FIFO
, ¶m
);
1082 * We keep the reference to the task struct even if
1083 * the thread dies to avoid that the interrupt code
1084 * references an already freed task_struct.
1089 * Tell the thread to set its affinity. This is
1090 * important for shared interrupt handlers as we do
1091 * not invoke setup_affinity() for the secondary
1092 * handlers as everything is already set up. Even for
1093 * interrupts marked with IRQF_NO_BALANCE this is
1094 * correct as we want the thread to move to the cpu(s)
1095 * on which the requesting code placed the interrupt.
1097 set_bit(IRQTF_AFFINITY
, &new->thread_flags
);
1100 if (!alloc_cpumask_var(&mask
, GFP_KERNEL
)) {
1106 * Drivers are often written to work w/o knowledge about the
1107 * underlying irq chip implementation, so a request for a
1108 * threaded irq without a primary hard irq context handler
1109 * requires the ONESHOT flag to be set. Some irq chips like
1110 * MSI based interrupts are per se one shot safe. Check the
1111 * chip flags, so we can avoid the unmask dance at the end of
1112 * the threaded handler for those.
1114 if (desc
->irq_data
.chip
->flags
& IRQCHIP_ONESHOT_SAFE
)
1115 new->flags
&= ~IRQF_ONESHOT
;
1118 * The following block of code has to be executed atomically
1120 raw_spin_lock_irqsave(&desc
->lock
, flags
);
1121 old_ptr
= &desc
->action
;
1125 * Can't share interrupts unless both agree to and are
1126 * the same type (level, edge, polarity). So both flag
1127 * fields must have IRQF_SHARED set and the bits which
1128 * set the trigger type must match. Also all must
1131 if (!((old
->flags
& new->flags
) & IRQF_SHARED
) ||
1132 ((old
->flags
^ new->flags
) & IRQF_TRIGGER_MASK
) ||
1133 ((old
->flags
^ new->flags
) & IRQF_ONESHOT
))
1136 /* All handlers must agree on per-cpuness */
1137 if ((old
->flags
& IRQF_PERCPU
) !=
1138 (new->flags
& IRQF_PERCPU
))
1141 /* add new interrupt at end of irq queue */
1144 * Or all existing action->thread_mask bits,
1145 * so we can find the next zero bit for this
1148 thread_mask
|= old
->thread_mask
;
1149 old_ptr
= &old
->next
;
1156 * Setup the thread mask for this irqaction for ONESHOT. For
1157 * !ONESHOT irqs the thread mask is 0 so we can avoid a
1158 * conditional in irq_wake_thread().
1160 if (new->flags
& IRQF_ONESHOT
) {
1162 * Unlikely to have 32 resp 64 irqs sharing one line,
1165 if (thread_mask
== ~0UL) {
1170 * The thread_mask for the action is or'ed to
1171 * desc->thread_active to indicate that the
1172 * IRQF_ONESHOT thread handler has been woken, but not
1173 * yet finished. The bit is cleared when a thread
1174 * completes. When all threads of a shared interrupt
1175 * line have completed desc->threads_active becomes
1176 * zero and the interrupt line is unmasked. See
1177 * handle.c:irq_wake_thread() for further information.
1179 * If no thread is woken by primary (hard irq context)
1180 * interrupt handlers, then desc->threads_active is
1181 * also checked for zero to unmask the irq line in the
1182 * affected hard irq flow handlers
1183 * (handle_[fasteoi|level]_irq).
1185 * The new action gets the first zero bit of
1186 * thread_mask assigned. See the loop above which or's
1187 * all existing action->thread_mask bits.
1189 new->thread_mask
= 1 << ffz(thread_mask
);
1191 } else if (new->handler
== irq_default_primary_handler
&&
1192 !(desc
->irq_data
.chip
->flags
& IRQCHIP_ONESHOT_SAFE
)) {
1194 * The interrupt was requested with handler = NULL, so
1195 * we use the default primary handler for it. But it
1196 * does not have the oneshot flag set. In combination
1197 * with level interrupts this is deadly, because the
1198 * default primary handler just wakes the thread, then
1199 * the irq lines is reenabled, but the device still
1200 * has the level irq asserted. Rinse and repeat....
1202 * While this works for edge type interrupts, we play
1203 * it safe and reject unconditionally because we can't
1204 * say for sure which type this interrupt really
1205 * has. The type flags are unreliable as the
1206 * underlying chip implementation can override them.
1208 pr_err("Threaded irq requested with handler=NULL and !ONESHOT for irq %d\n",
1215 ret
= irq_request_resources(desc
);
1217 pr_err("Failed to request resources for %s (irq %d) on irqchip %s\n",
1218 new->name
, irq
, desc
->irq_data
.chip
->name
);
1222 init_waitqueue_head(&desc
->wait_for_threads
);
1224 /* Setup the type (level, edge polarity) if configured: */
1225 if (new->flags
& IRQF_TRIGGER_MASK
) {
1226 ret
= __irq_set_trigger(desc
,
1227 new->flags
& IRQF_TRIGGER_MASK
);
1233 desc
->istate
&= ~(IRQS_AUTODETECT
| IRQS_SPURIOUS_DISABLED
| \
1234 IRQS_ONESHOT
| IRQS_WAITING
);
1235 irqd_clear(&desc
->irq_data
, IRQD_IRQ_INPROGRESS
);
1237 if (new->flags
& IRQF_PERCPU
) {
1238 irqd_set(&desc
->irq_data
, IRQD_PER_CPU
);
1239 irq_settings_set_per_cpu(desc
);
1242 if (new->flags
& IRQF_ONESHOT
)
1243 desc
->istate
|= IRQS_ONESHOT
;
1245 if (irq_settings_can_autoenable(desc
))
1246 irq_startup(desc
, true);
1248 /* Undo nested disables: */
1251 /* Exclude IRQ from balancing if requested */
1252 if (new->flags
& IRQF_NOBALANCING
) {
1253 irq_settings_set_no_balancing(desc
);
1254 irqd_set(&desc
->irq_data
, IRQD_NO_BALANCING
);
1257 /* Set default affinity mask once everything is setup */
1258 setup_affinity(desc
, mask
);
1260 } else if (new->flags
& IRQF_TRIGGER_MASK
) {
1261 unsigned int nmsk
= new->flags
& IRQF_TRIGGER_MASK
;
1262 unsigned int omsk
= irq_settings_get_trigger_mask(desc
);
1265 /* hope the handler works with current trigger mode */
1266 pr_warning("irq %d uses trigger mode %u; requested %u\n",
1273 irq_pm_install_action(desc
, new);
1275 /* Reset broken irq detection when installing new handler */
1276 desc
->irq_count
= 0;
1277 desc
->irqs_unhandled
= 0;
1280 * Check whether we disabled the irq via the spurious handler
1281 * before. Reenable it and give it another chance.
1283 if (shared
&& (desc
->istate
& IRQS_SPURIOUS_DISABLED
)) {
1284 desc
->istate
&= ~IRQS_SPURIOUS_DISABLED
;
1288 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
1291 * Strictly no need to wake it up, but hung_task complains
1292 * when no hard interrupt wakes the thread up.
1295 wake_up_process(new->thread
);
1297 register_irq_proc(irq
, desc
);
1299 register_handler_proc(irq
, new);
1300 free_cpumask_var(mask
);
1305 if (!(new->flags
& IRQF_PROBE_SHARED
)) {
1306 pr_err("Flags mismatch irq %d. %08x (%s) vs. %08x (%s)\n",
1307 irq
, new->flags
, new->name
, old
->flags
, old
->name
);
1308 #ifdef CONFIG_DEBUG_SHIRQ
1315 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
1316 free_cpumask_var(mask
);
1320 struct task_struct
*t
= new->thread
;
1327 module_put(desc
->owner
);
1332 * setup_irq - setup an interrupt
1333 * @irq: Interrupt line to setup
1334 * @act: irqaction for the interrupt
1336 * Used to statically setup interrupts in the early boot process.
1338 int setup_irq(unsigned int irq
, struct irqaction
*act
)
1341 struct irq_desc
*desc
= irq_to_desc(irq
);
1343 if (WARN_ON(irq_settings_is_per_cpu_devid(desc
)))
1345 chip_bus_lock(desc
);
1346 retval
= __setup_irq(irq
, desc
, act
);
1347 chip_bus_sync_unlock(desc
);
1351 EXPORT_SYMBOL_GPL(setup_irq
);
1354 * Internal function to unregister an irqaction - used to free
1355 * regular and special interrupts that are part of the architecture.
1357 static struct irqaction
*__free_irq(unsigned int irq
, void *dev_id
)
1359 struct irq_desc
*desc
= irq_to_desc(irq
);
1360 struct irqaction
*action
, **action_ptr
;
1361 unsigned long flags
;
1363 WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq
);
1368 raw_spin_lock_irqsave(&desc
->lock
, flags
);
1371 * There can be multiple actions per IRQ descriptor, find the right
1372 * one based on the dev_id:
1374 action_ptr
= &desc
->action
;
1376 action
= *action_ptr
;
1379 WARN(1, "Trying to free already-free IRQ %d\n", irq
);
1380 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
1385 if (action
->dev_id
== dev_id
)
1387 action_ptr
= &action
->next
;
1390 /* Found it - now remove it from the list of entries: */
1391 *action_ptr
= action
->next
;
1393 irq_pm_remove_action(desc
, action
);
1395 /* If this was the last handler, shut down the IRQ line: */
1396 if (!desc
->action
) {
1398 irq_release_resources(desc
);
1402 /* make sure affinity_hint is cleaned up */
1403 if (WARN_ON_ONCE(desc
->affinity_hint
))
1404 desc
->affinity_hint
= NULL
;
1407 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
1409 unregister_handler_proc(irq
, action
);
1411 /* Make sure it's not being used on another CPU: */
1412 synchronize_irq(irq
);
1414 #ifdef CONFIG_DEBUG_SHIRQ
1416 * It's a shared IRQ -- the driver ought to be prepared for an IRQ
1417 * event to happen even now it's being freed, so let's make sure that
1418 * is so by doing an extra call to the handler ....
1420 * ( We do this after actually deregistering it, to make sure that a
1421 * 'real' IRQ doesn't run in * parallel with our fake. )
1423 if (action
->flags
& IRQF_SHARED
) {
1424 local_irq_save(flags
);
1425 action
->handler(irq
, dev_id
);
1426 local_irq_restore(flags
);
1430 if (action
->thread
) {
1431 kthread_stop(action
->thread
);
1432 put_task_struct(action
->thread
);
1435 module_put(desc
->owner
);
1440 * remove_irq - free an interrupt
1441 * @irq: Interrupt line to free
1442 * @act: irqaction for the interrupt
1444 * Used to remove interrupts statically setup by the early boot process.
1446 void remove_irq(unsigned int irq
, struct irqaction
*act
)
1448 struct irq_desc
*desc
= irq_to_desc(irq
);
1450 if (desc
&& !WARN_ON(irq_settings_is_per_cpu_devid(desc
)))
1451 __free_irq(irq
, act
->dev_id
);
1453 EXPORT_SYMBOL_GPL(remove_irq
);
1456 * free_irq - free an interrupt allocated with request_irq
1457 * @irq: Interrupt line to free
1458 * @dev_id: Device identity to free
1460 * Remove an interrupt handler. The handler is removed and if the
1461 * interrupt line is no longer in use by any driver it is disabled.
1462 * On a shared IRQ the caller must ensure the interrupt is disabled
1463 * on the card it drives before calling this function. The function
1464 * does not return until any executing interrupts for this IRQ
1467 * This function must not be called from interrupt context.
1469 void free_irq(unsigned int irq
, void *dev_id
)
1471 struct irq_desc
*desc
= irq_to_desc(irq
);
1473 if (!desc
|| WARN_ON(irq_settings_is_per_cpu_devid(desc
)))
1477 if (WARN_ON(desc
->affinity_notify
))
1478 desc
->affinity_notify
= NULL
;
1481 chip_bus_lock(desc
);
1482 kfree(__free_irq(irq
, dev_id
));
1483 chip_bus_sync_unlock(desc
);
1485 EXPORT_SYMBOL(free_irq
);
1488 * request_threaded_irq - allocate an interrupt line
1489 * @irq: Interrupt line to allocate
1490 * @handler: Function to be called when the IRQ occurs.
1491 * Primary handler for threaded interrupts
1492 * If NULL and thread_fn != NULL the default
1493 * primary handler is installed
1494 * @thread_fn: Function called from the irq handler thread
1495 * If NULL, no irq thread is created
1496 * @irqflags: Interrupt type flags
1497 * @devname: An ascii name for the claiming device
1498 * @dev_id: A cookie passed back to the handler function
1500 * This call allocates interrupt resources and enables the
1501 * interrupt line and IRQ handling. From the point this
1502 * call is made your handler function may be invoked. Since
1503 * your handler function must clear any interrupt the board
1504 * raises, you must take care both to initialise your hardware
1505 * and to set up the interrupt handler in the right order.
1507 * If you want to set up a threaded irq handler for your device
1508 * then you need to supply @handler and @thread_fn. @handler is
1509 * still called in hard interrupt context and has to check
1510 * whether the interrupt originates from the device. If yes it
1511 * needs to disable the interrupt on the device and return
1512 * IRQ_WAKE_THREAD which will wake up the handler thread and run
1513 * @thread_fn. This split handler design is necessary to support
1514 * shared interrupts.
1516 * Dev_id must be globally unique. Normally the address of the
1517 * device data structure is used as the cookie. Since the handler
1518 * receives this value it makes sense to use it.
1520 * If your interrupt is shared you must pass a non NULL dev_id
1521 * as this is required when freeing the interrupt.
1525 * IRQF_SHARED Interrupt is shared
1526 * IRQF_TRIGGER_* Specify active edge(s) or level
1529 int request_threaded_irq(unsigned int irq
, irq_handler_t handler
,
1530 irq_handler_t thread_fn
, unsigned long irqflags
,
1531 const char *devname
, void *dev_id
)
1533 struct irqaction
*action
;
1534 struct irq_desc
*desc
;
1538 * Sanity-check: shared interrupts must pass in a real dev-ID,
1539 * otherwise we'll have trouble later trying to figure out
1540 * which interrupt is which (messes up the interrupt freeing
1543 * Also IRQF_COND_SUSPEND only makes sense for shared interrupts and
1544 * it cannot be set along with IRQF_NO_SUSPEND.
1546 if (((irqflags
& IRQF_SHARED
) && !dev_id
) ||
1547 (!(irqflags
& IRQF_SHARED
) && (irqflags
& IRQF_COND_SUSPEND
)) ||
1548 ((irqflags
& IRQF_NO_SUSPEND
) && (irqflags
& IRQF_COND_SUSPEND
)))
1551 desc
= irq_to_desc(irq
);
1555 if (!irq_settings_can_request(desc
) ||
1556 WARN_ON(irq_settings_is_per_cpu_devid(desc
)))
1562 handler
= irq_default_primary_handler
;
1565 action
= kzalloc(sizeof(struct irqaction
), GFP_KERNEL
);
1569 action
->handler
= handler
;
1570 action
->thread_fn
= thread_fn
;
1571 action
->flags
= irqflags
;
1572 action
->name
= devname
;
1573 action
->dev_id
= dev_id
;
1575 chip_bus_lock(desc
);
1576 retval
= __setup_irq(irq
, desc
, action
);
1577 chip_bus_sync_unlock(desc
);
1582 #ifdef CONFIG_DEBUG_SHIRQ_FIXME
1583 if (!retval
&& (irqflags
& IRQF_SHARED
)) {
1585 * It's a shared IRQ -- the driver ought to be prepared for it
1586 * to happen immediately, so let's make sure....
1587 * We disable the irq to make sure that a 'real' IRQ doesn't
1588 * run in parallel with our fake.
1590 unsigned long flags
;
1593 local_irq_save(flags
);
1595 handler(irq
, dev_id
);
1597 local_irq_restore(flags
);
1603 EXPORT_SYMBOL(request_threaded_irq
);
1606 * request_any_context_irq - allocate an interrupt line
1607 * @irq: Interrupt line to allocate
1608 * @handler: Function to be called when the IRQ occurs.
1609 * Threaded handler for threaded interrupts.
1610 * @flags: Interrupt type flags
1611 * @name: An ascii name for the claiming device
1612 * @dev_id: A cookie passed back to the handler function
1614 * This call allocates interrupt resources and enables the
1615 * interrupt line and IRQ handling. It selects either a
1616 * hardirq or threaded handling method depending on the
1619 * On failure, it returns a negative value. On success,
1620 * it returns either IRQC_IS_HARDIRQ or IRQC_IS_NESTED.
1622 int request_any_context_irq(unsigned int irq
, irq_handler_t handler
,
1623 unsigned long flags
, const char *name
, void *dev_id
)
1625 struct irq_desc
*desc
= irq_to_desc(irq
);
1631 if (irq_settings_is_nested_thread(desc
)) {
1632 ret
= request_threaded_irq(irq
, NULL
, handler
,
1633 flags
, name
, dev_id
);
1634 return !ret
? IRQC_IS_NESTED
: ret
;
1637 ret
= request_irq(irq
, handler
, flags
, name
, dev_id
);
1638 return !ret
? IRQC_IS_HARDIRQ
: ret
;
1640 EXPORT_SYMBOL_GPL(request_any_context_irq
);
1642 void enable_percpu_irq(unsigned int irq
, unsigned int type
)
1644 unsigned int cpu
= smp_processor_id();
1645 unsigned long flags
;
1646 struct irq_desc
*desc
= irq_get_desc_lock(irq
, &flags
, IRQ_GET_DESC_CHECK_PERCPU
);
1651 type
&= IRQ_TYPE_SENSE_MASK
;
1652 if (type
!= IRQ_TYPE_NONE
) {
1655 ret
= __irq_set_trigger(desc
, type
);
1658 WARN(1, "failed to set type for IRQ%d\n", irq
);
1663 irq_percpu_enable(desc
, cpu
);
1665 irq_put_desc_unlock(desc
, flags
);
1667 EXPORT_SYMBOL_GPL(enable_percpu_irq
);
1669 void disable_percpu_irq(unsigned int irq
)
1671 unsigned int cpu
= smp_processor_id();
1672 unsigned long flags
;
1673 struct irq_desc
*desc
= irq_get_desc_lock(irq
, &flags
, IRQ_GET_DESC_CHECK_PERCPU
);
1678 irq_percpu_disable(desc
, cpu
);
1679 irq_put_desc_unlock(desc
, flags
);
1681 EXPORT_SYMBOL_GPL(disable_percpu_irq
);
1684 * Internal function to unregister a percpu irqaction.
1686 static struct irqaction
*__free_percpu_irq(unsigned int irq
, void __percpu
*dev_id
)
1688 struct irq_desc
*desc
= irq_to_desc(irq
);
1689 struct irqaction
*action
;
1690 unsigned long flags
;
1692 WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq
);
1697 raw_spin_lock_irqsave(&desc
->lock
, flags
);
1699 action
= desc
->action
;
1700 if (!action
|| action
->percpu_dev_id
!= dev_id
) {
1701 WARN(1, "Trying to free already-free IRQ %d\n", irq
);
1705 if (!cpumask_empty(desc
->percpu_enabled
)) {
1706 WARN(1, "percpu IRQ %d still enabled on CPU%d!\n",
1707 irq
, cpumask_first(desc
->percpu_enabled
));
1711 /* Found it - now remove it from the list of entries: */
1712 desc
->action
= NULL
;
1714 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
1716 unregister_handler_proc(irq
, action
);
1718 module_put(desc
->owner
);
1722 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
1727 * remove_percpu_irq - free a per-cpu interrupt
1728 * @irq: Interrupt line to free
1729 * @act: irqaction for the interrupt
1731 * Used to remove interrupts statically setup by the early boot process.
1733 void remove_percpu_irq(unsigned int irq
, struct irqaction
*act
)
1735 struct irq_desc
*desc
= irq_to_desc(irq
);
1737 if (desc
&& irq_settings_is_per_cpu_devid(desc
))
1738 __free_percpu_irq(irq
, act
->percpu_dev_id
);
1742 * free_percpu_irq - free an interrupt allocated with request_percpu_irq
1743 * @irq: Interrupt line to free
1744 * @dev_id: Device identity to free
1746 * Remove a percpu interrupt handler. The handler is removed, but
1747 * the interrupt line is not disabled. This must be done on each
1748 * CPU before calling this function. The function does not return
1749 * until any executing interrupts for this IRQ have completed.
1751 * This function must not be called from interrupt context.
1753 void free_percpu_irq(unsigned int irq
, void __percpu
*dev_id
)
1755 struct irq_desc
*desc
= irq_to_desc(irq
);
1757 if (!desc
|| !irq_settings_is_per_cpu_devid(desc
))
1760 chip_bus_lock(desc
);
1761 kfree(__free_percpu_irq(irq
, dev_id
));
1762 chip_bus_sync_unlock(desc
);
1766 * setup_percpu_irq - setup a per-cpu interrupt
1767 * @irq: Interrupt line to setup
1768 * @act: irqaction for the interrupt
1770 * Used to statically setup per-cpu interrupts in the early boot process.
1772 int setup_percpu_irq(unsigned int irq
, struct irqaction
*act
)
1774 struct irq_desc
*desc
= irq_to_desc(irq
);
1777 if (!desc
|| !irq_settings_is_per_cpu_devid(desc
))
1779 chip_bus_lock(desc
);
1780 retval
= __setup_irq(irq
, desc
, act
);
1781 chip_bus_sync_unlock(desc
);
1787 * request_percpu_irq - allocate a percpu interrupt line
1788 * @irq: Interrupt line to allocate
1789 * @handler: Function to be called when the IRQ occurs.
1790 * @devname: An ascii name for the claiming device
1791 * @dev_id: A percpu cookie passed back to the handler function
1793 * This call allocates interrupt resources, but doesn't
1794 * automatically enable the interrupt. It has to be done on each
1795 * CPU using enable_percpu_irq().
1797 * Dev_id must be globally unique. It is a per-cpu variable, and
1798 * the handler gets called with the interrupted CPU's instance of
1801 int request_percpu_irq(unsigned int irq
, irq_handler_t handler
,
1802 const char *devname
, void __percpu
*dev_id
)
1804 struct irqaction
*action
;
1805 struct irq_desc
*desc
;
1811 desc
= irq_to_desc(irq
);
1812 if (!desc
|| !irq_settings_can_request(desc
) ||
1813 !irq_settings_is_per_cpu_devid(desc
))
1816 action
= kzalloc(sizeof(struct irqaction
), GFP_KERNEL
);
1820 action
->handler
= handler
;
1821 action
->flags
= IRQF_PERCPU
| IRQF_NO_SUSPEND
;
1822 action
->name
= devname
;
1823 action
->percpu_dev_id
= dev_id
;
1825 chip_bus_lock(desc
);
1826 retval
= __setup_irq(irq
, desc
, action
);
1827 chip_bus_sync_unlock(desc
);
1836 * irq_get_irqchip_state - returns the irqchip state of a interrupt.
1837 * @irq: Interrupt line that is forwarded to a VM
1838 * @which: One of IRQCHIP_STATE_* the caller wants to know about
1839 * @state: a pointer to a boolean where the state is to be storeed
1841 * This call snapshots the internal irqchip state of an
1842 * interrupt, returning into @state the bit corresponding to
1845 * This function should be called with preemption disabled if the
1846 * interrupt controller has per-cpu registers.
1848 int irq_get_irqchip_state(unsigned int irq
, enum irqchip_irq_state which
,
1851 struct irq_desc
*desc
;
1852 struct irq_data
*data
;
1853 struct irq_chip
*chip
;
1854 unsigned long flags
;
1857 desc
= irq_get_desc_buslock(irq
, &flags
, 0);
1861 data
= irq_desc_get_irq_data(desc
);
1864 chip
= irq_data_get_irq_chip(data
);
1865 if (chip
->irq_get_irqchip_state
)
1867 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1868 data
= data
->parent_data
;
1875 err
= chip
->irq_get_irqchip_state(data
, which
, state
);
1877 irq_put_desc_busunlock(desc
, flags
);
1880 EXPORT_SYMBOL_GPL(irq_get_irqchip_state
);
1883 * irq_set_irqchip_state - set the state of a forwarded interrupt.
1884 * @irq: Interrupt line that is forwarded to a VM
1885 * @which: State to be restored (one of IRQCHIP_STATE_*)
1886 * @val: Value corresponding to @which
1888 * This call sets the internal irqchip state of an interrupt,
1889 * depending on the value of @which.
1891 * This function should be called with preemption disabled if the
1892 * interrupt controller has per-cpu registers.
1894 int irq_set_irqchip_state(unsigned int irq
, enum irqchip_irq_state which
,
1897 struct irq_desc
*desc
;
1898 struct irq_data
*data
;
1899 struct irq_chip
*chip
;
1900 unsigned long flags
;
1903 desc
= irq_get_desc_buslock(irq
, &flags
, 0);
1907 data
= irq_desc_get_irq_data(desc
);
1910 chip
= irq_data_get_irq_chip(data
);
1911 if (chip
->irq_set_irqchip_state
)
1913 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1914 data
= data
->parent_data
;
1921 err
= chip
->irq_set_irqchip_state(data
, which
, val
);
1923 irq_put_desc_busunlock(desc
, flags
);
1926 EXPORT_SYMBOL_GPL(irq_set_irqchip_state
);