4 * Xen models interrupts with abstract event channels. Because each
5 * domain gets 1024 event channels, but NR_IRQ is not that large, we
6 * must dynamically map irqs<->event channels. The event channels
7 * interface with the rest of the kernel by defining a xen interrupt
8 * chip. When an event is recieved, it is mapped to an irq and sent
9 * through the normal interrupt processing path.
11 * There are four kinds of events which can be mapped to an event
14 * 1. Inter-domain notifications. This includes all the virtual
15 * device events, since they're driven by front-ends in another domain
17 * 2. VIRQs, typically used for timers. These are per-cpu events.
19 * 4. Hardware interrupts. Not supported at present.
21 * Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007
24 #include <linux/linkage.h>
25 #include <linux/interrupt.h>
26 #include <linux/irq.h>
27 #include <linux/module.h>
28 #include <linux/string.h>
30 #include <asm/ptrace.h>
32 #include <asm/sync_bitops.h>
33 #include <asm/xen/hypercall.h>
34 #include <asm/xen/hypervisor.h>
36 #include <xen/xen-ops.h>
37 #include <xen/events.h>
38 #include <xen/interface/xen.h>
39 #include <xen/interface/event_channel.h>
42 * This lock protects updates to the following mapping and reference-count
43 * arrays. The lock does not need to be acquired to read the mapping tables.
45 static DEFINE_SPINLOCK(irq_mapping_update_lock
);
47 /* IRQ <-> VIRQ mapping. */
48 static DEFINE_PER_CPU(int, virq_to_irq
[NR_VIRQS
]) = {[0 ... NR_VIRQS
-1] = -1};
50 /* IRQ <-> IPI mapping */
51 static DEFINE_PER_CPU(int, ipi_to_irq
[XEN_NR_IPIS
]) = {[0 ... XEN_NR_IPIS
-1] = -1};
53 /* Packed IRQ information: binding type, sub-type index, and event channel. */
56 unsigned short evtchn
;
61 static struct packed_irq irq_info
[NR_IRQS
];
72 /* Convenient shorthand for packed representation of an unbound IRQ. */
73 #define IRQ_UNBOUND mk_irq_info(IRQT_UNBOUND, 0, 0)
75 static int evtchn_to_irq
[NR_EVENT_CHANNELS
] = {
76 [0 ... NR_EVENT_CHANNELS
-1] = -1
78 static unsigned long cpu_evtchn_mask
[NR_CPUS
][NR_EVENT_CHANNELS
/BITS_PER_LONG
];
79 static u8 cpu_evtchn
[NR_EVENT_CHANNELS
];
81 /* Reference counts for bindings to IRQs. */
82 static int irq_bindcount
[NR_IRQS
];
84 /* Xen will never allocate port zero for any purpose. */
85 #define VALID_EVTCHN(chn) ((chn) != 0)
87 static struct irq_chip xen_dynamic_chip
;
89 /* Constructor for packed IRQ information. */
90 static inline struct packed_irq
mk_irq_info(u32 type
, u32 index
, u32 evtchn
)
92 return (struct packed_irq
) { evtchn
, index
, type
};
96 * Accessors for packed IRQ information.
98 static inline unsigned int evtchn_from_irq(int irq
)
100 return irq_info
[irq
].evtchn
;
103 static inline unsigned int index_from_irq(int irq
)
105 return irq_info
[irq
].index
;
108 static inline unsigned int type_from_irq(int irq
)
110 return irq_info
[irq
].type
;
113 static inline unsigned long active_evtchns(unsigned int cpu
,
114 struct shared_info
*sh
,
117 return (sh
->evtchn_pending
[idx
] &
118 cpu_evtchn_mask
[cpu
][idx
] &
119 ~sh
->evtchn_mask
[idx
]);
122 static void bind_evtchn_to_cpu(unsigned int chn
, unsigned int cpu
)
124 int irq
= evtchn_to_irq
[chn
];
128 irq_to_desc(irq
)->affinity
= cpumask_of_cpu(cpu
);
131 __clear_bit(chn
, cpu_evtchn_mask
[cpu_evtchn
[chn
]]);
132 __set_bit(chn
, cpu_evtchn_mask
[cpu
]);
134 cpu_evtchn
[chn
] = cpu
;
137 static void init_evtchn_cpu_bindings(void)
140 struct irq_desc
*desc
;
143 /* By default all event channels notify CPU#0. */
144 for_each_irq_desc(i
, desc
) {
148 desc
->affinity
= cpumask_of_cpu(0);
152 memset(cpu_evtchn
, 0, sizeof(cpu_evtchn
));
153 memset(cpu_evtchn_mask
[0], ~0, sizeof(cpu_evtchn_mask
[0]));
156 static inline unsigned int cpu_from_evtchn(unsigned int evtchn
)
158 return cpu_evtchn
[evtchn
];
161 static inline void clear_evtchn(int port
)
163 struct shared_info
*s
= HYPERVISOR_shared_info
;
164 sync_clear_bit(port
, &s
->evtchn_pending
[0]);
167 static inline void set_evtchn(int port
)
169 struct shared_info
*s
= HYPERVISOR_shared_info
;
170 sync_set_bit(port
, &s
->evtchn_pending
[0]);
173 static inline int test_evtchn(int port
)
175 struct shared_info
*s
= HYPERVISOR_shared_info
;
176 return sync_test_bit(port
, &s
->evtchn_pending
[0]);
181 * notify_remote_via_irq - send event to remote end of event channel via irq
182 * @irq: irq of event channel to send event to
184 * Unlike notify_remote_via_evtchn(), this is safe to use across
185 * save/restore. Notifications on a broken connection are silently
188 void notify_remote_via_irq(int irq
)
190 int evtchn
= evtchn_from_irq(irq
);
192 if (VALID_EVTCHN(evtchn
))
193 notify_remote_via_evtchn(evtchn
);
195 EXPORT_SYMBOL_GPL(notify_remote_via_irq
);
197 static void mask_evtchn(int port
)
199 struct shared_info
*s
= HYPERVISOR_shared_info
;
200 sync_set_bit(port
, &s
->evtchn_mask
[0]);
203 static void unmask_evtchn(int port
)
205 struct shared_info
*s
= HYPERVISOR_shared_info
;
206 unsigned int cpu
= get_cpu();
208 BUG_ON(!irqs_disabled());
210 /* Slow path (hypercall) if this is a non-local port. */
211 if (unlikely(cpu
!= cpu_from_evtchn(port
))) {
212 struct evtchn_unmask unmask
= { .port
= port
};
213 (void)HYPERVISOR_event_channel_op(EVTCHNOP_unmask
, &unmask
);
215 struct vcpu_info
*vcpu_info
= __get_cpu_var(xen_vcpu
);
217 sync_clear_bit(port
, &s
->evtchn_mask
[0]);
220 * The following is basically the equivalent of
221 * 'hw_resend_irq'. Just like a real IO-APIC we 'lose
222 * the interrupt edge' if the channel is masked.
224 if (sync_test_bit(port
, &s
->evtchn_pending
[0]) &&
225 !sync_test_and_set_bit(port
/ BITS_PER_LONG
,
226 &vcpu_info
->evtchn_pending_sel
))
227 vcpu_info
->evtchn_upcall_pending
= 1;
233 static int find_unbound_irq(void)
237 /* Only allocate from dynirq range */
238 for (irq
= 0; irq
< nr_irqs
; irq
++)
239 if (irq_bindcount
[irq
] == 0)
243 panic("No available IRQ to bind to: increase nr_irqs!\n");
248 int bind_evtchn_to_irq(unsigned int evtchn
)
252 spin_lock(&irq_mapping_update_lock
);
254 irq
= evtchn_to_irq
[evtchn
];
257 irq
= find_unbound_irq();
259 dynamic_irq_init(irq
);
260 set_irq_chip_and_handler_name(irq
, &xen_dynamic_chip
,
261 handle_level_irq
, "event");
263 evtchn_to_irq
[evtchn
] = irq
;
264 irq_info
[irq
] = mk_irq_info(IRQT_EVTCHN
, 0, evtchn
);
267 irq_bindcount
[irq
]++;
269 spin_unlock(&irq_mapping_update_lock
);
273 EXPORT_SYMBOL_GPL(bind_evtchn_to_irq
);
275 static int bind_ipi_to_irq(unsigned int ipi
, unsigned int cpu
)
277 struct evtchn_bind_ipi bind_ipi
;
280 spin_lock(&irq_mapping_update_lock
);
282 irq
= per_cpu(ipi_to_irq
, cpu
)[ipi
];
284 irq
= find_unbound_irq();
288 dynamic_irq_init(irq
);
289 set_irq_chip_and_handler_name(irq
, &xen_dynamic_chip
,
290 handle_level_irq
, "ipi");
293 if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_ipi
,
296 evtchn
= bind_ipi
.port
;
298 evtchn_to_irq
[evtchn
] = irq
;
299 irq_info
[irq
] = mk_irq_info(IRQT_IPI
, ipi
, evtchn
);
301 per_cpu(ipi_to_irq
, cpu
)[ipi
] = irq
;
303 bind_evtchn_to_cpu(evtchn
, cpu
);
306 irq_bindcount
[irq
]++;
309 spin_unlock(&irq_mapping_update_lock
);
314 static int bind_virq_to_irq(unsigned int virq
, unsigned int cpu
)
316 struct evtchn_bind_virq bind_virq
;
319 spin_lock(&irq_mapping_update_lock
);
321 irq
= per_cpu(virq_to_irq
, cpu
)[virq
];
324 bind_virq
.virq
= virq
;
325 bind_virq
.vcpu
= cpu
;
326 if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_virq
,
329 evtchn
= bind_virq
.port
;
331 irq
= find_unbound_irq();
333 dynamic_irq_init(irq
);
334 set_irq_chip_and_handler_name(irq
, &xen_dynamic_chip
,
335 handle_level_irq
, "virq");
337 evtchn_to_irq
[evtchn
] = irq
;
338 irq_info
[irq
] = mk_irq_info(IRQT_VIRQ
, virq
, evtchn
);
340 per_cpu(virq_to_irq
, cpu
)[virq
] = irq
;
342 bind_evtchn_to_cpu(evtchn
, cpu
);
345 irq_bindcount
[irq
]++;
347 spin_unlock(&irq_mapping_update_lock
);
352 static void unbind_from_irq(unsigned int irq
)
354 struct evtchn_close close
;
355 int evtchn
= evtchn_from_irq(irq
);
357 spin_lock(&irq_mapping_update_lock
);
359 if ((--irq_bindcount
[irq
] == 0) && VALID_EVTCHN(evtchn
)) {
361 if (HYPERVISOR_event_channel_op(EVTCHNOP_close
, &close
) != 0)
364 switch (type_from_irq(irq
)) {
366 per_cpu(virq_to_irq
, cpu_from_evtchn(evtchn
))
367 [index_from_irq(irq
)] = -1;
370 per_cpu(ipi_to_irq
, cpu_from_evtchn(evtchn
))
371 [index_from_irq(irq
)] = -1;
377 /* Closed ports are implicitly re-bound to VCPU0. */
378 bind_evtchn_to_cpu(evtchn
, 0);
380 evtchn_to_irq
[evtchn
] = -1;
381 irq_info
[irq
] = IRQ_UNBOUND
;
383 dynamic_irq_cleanup(irq
);
386 spin_unlock(&irq_mapping_update_lock
);
389 int bind_evtchn_to_irqhandler(unsigned int evtchn
,
390 irq_handler_t handler
,
391 unsigned long irqflags
,
392 const char *devname
, void *dev_id
)
397 irq
= bind_evtchn_to_irq(evtchn
);
398 retval
= request_irq(irq
, handler
, irqflags
, devname
, dev_id
);
400 unbind_from_irq(irq
);
406 EXPORT_SYMBOL_GPL(bind_evtchn_to_irqhandler
);
408 int bind_virq_to_irqhandler(unsigned int virq
, unsigned int cpu
,
409 irq_handler_t handler
,
410 unsigned long irqflags
, const char *devname
, void *dev_id
)
415 irq
= bind_virq_to_irq(virq
, cpu
);
416 retval
= request_irq(irq
, handler
, irqflags
, devname
, dev_id
);
418 unbind_from_irq(irq
);
424 EXPORT_SYMBOL_GPL(bind_virq_to_irqhandler
);
426 int bind_ipi_to_irqhandler(enum ipi_vector ipi
,
428 irq_handler_t handler
,
429 unsigned long irqflags
,
435 irq
= bind_ipi_to_irq(ipi
, cpu
);
439 retval
= request_irq(irq
, handler
, irqflags
, devname
, dev_id
);
441 unbind_from_irq(irq
);
448 void unbind_from_irqhandler(unsigned int irq
, void *dev_id
)
450 free_irq(irq
, dev_id
);
451 unbind_from_irq(irq
);
453 EXPORT_SYMBOL_GPL(unbind_from_irqhandler
);
455 void xen_send_IPI_one(unsigned int cpu
, enum ipi_vector vector
)
457 int irq
= per_cpu(ipi_to_irq
, cpu
)[vector
];
459 notify_remote_via_irq(irq
);
462 irqreturn_t
xen_debug_interrupt(int irq
, void *dev_id
)
464 struct shared_info
*sh
= HYPERVISOR_shared_info
;
465 int cpu
= smp_processor_id();
468 static DEFINE_SPINLOCK(debug_lock
);
470 spin_lock_irqsave(&debug_lock
, flags
);
472 printk("vcpu %d\n ", cpu
);
474 for_each_online_cpu(i
) {
475 struct vcpu_info
*v
= per_cpu(xen_vcpu
, i
);
476 printk("%d: masked=%d pending=%d event_sel %08lx\n ", i
,
477 (get_irq_regs() && i
== cpu
) ? xen_irqs_disabled(get_irq_regs()) : v
->evtchn_upcall_mask
,
478 v
->evtchn_upcall_pending
,
479 v
->evtchn_pending_sel
);
481 printk("pending:\n ");
482 for(i
= ARRAY_SIZE(sh
->evtchn_pending
)-1; i
>= 0; i
--)
483 printk("%08lx%s", sh
->evtchn_pending
[i
],
484 i
% 8 == 0 ? "\n " : " ");
485 printk("\nmasks:\n ");
486 for(i
= ARRAY_SIZE(sh
->evtchn_mask
)-1; i
>= 0; i
--)
487 printk("%08lx%s", sh
->evtchn_mask
[i
],
488 i
% 8 == 0 ? "\n " : " ");
490 printk("\nunmasked:\n ");
491 for(i
= ARRAY_SIZE(sh
->evtchn_mask
)-1; i
>= 0; i
--)
492 printk("%08lx%s", sh
->evtchn_pending
[i
] & ~sh
->evtchn_mask
[i
],
493 i
% 8 == 0 ? "\n " : " ");
495 printk("\npending list:\n");
496 for(i
= 0; i
< NR_EVENT_CHANNELS
; i
++) {
497 if (sync_test_bit(i
, sh
->evtchn_pending
)) {
498 printk(" %d: event %d -> irq %d\n",
504 spin_unlock_irqrestore(&debug_lock
, flags
);
511 * Search the CPUs pending events bitmasks. For each one found, map
512 * the event number to an irq, and feed it into do_IRQ() for
515 * Xen uses a two-level bitmap to speed searching. The first level is
516 * a bitset of words which contain pending event bits. The second
517 * level is a bitset of pending events themselves.
519 void xen_evtchn_do_upcall(struct pt_regs
*regs
)
522 struct shared_info
*s
= HYPERVISOR_shared_info
;
523 struct vcpu_info
*vcpu_info
= __get_cpu_var(xen_vcpu
);
524 static DEFINE_PER_CPU(unsigned, nesting_count
);
528 unsigned long pending_words
;
530 vcpu_info
->evtchn_upcall_pending
= 0;
532 if (__get_cpu_var(nesting_count
)++)
535 #ifndef CONFIG_X86 /* No need for a barrier -- XCHG is a barrier on x86. */
536 /* Clear master flag /before/ clearing selector flag. */
539 pending_words
= xchg(&vcpu_info
->evtchn_pending_sel
, 0);
540 while (pending_words
!= 0) {
541 unsigned long pending_bits
;
542 int word_idx
= __ffs(pending_words
);
543 pending_words
&= ~(1UL << word_idx
);
545 while ((pending_bits
= active_evtchns(cpu
, s
, word_idx
)) != 0) {
546 int bit_idx
= __ffs(pending_bits
);
547 int port
= (word_idx
* BITS_PER_LONG
) + bit_idx
;
548 int irq
= evtchn_to_irq
[port
];
551 xen_do_IRQ(irq
, regs
);
555 BUG_ON(!irqs_disabled());
557 count
= __get_cpu_var(nesting_count
);
558 __get_cpu_var(nesting_count
) = 0;
565 /* Rebind a new event channel to an existing irq. */
566 void rebind_evtchn_irq(int evtchn
, int irq
)
568 /* Make sure the irq is masked, since the new event channel
569 will also be masked. */
572 spin_lock(&irq_mapping_update_lock
);
574 /* After resume the irq<->evtchn mappings are all cleared out */
575 BUG_ON(evtchn_to_irq
[evtchn
] != -1);
576 /* Expect irq to have been bound before,
577 so the bindcount should be non-0 */
578 BUG_ON(irq_bindcount
[irq
] == 0);
580 evtchn_to_irq
[evtchn
] = irq
;
581 irq_info
[irq
] = mk_irq_info(IRQT_EVTCHN
, 0, evtchn
);
583 spin_unlock(&irq_mapping_update_lock
);
585 /* new event channels are always bound to cpu 0 */
586 irq_set_affinity(irq
, cpumask_of_cpu(0));
588 /* Unmask the event channel. */
592 /* Rebind an evtchn so that it gets delivered to a specific cpu */
593 static void rebind_irq_to_cpu(unsigned irq
, unsigned tcpu
)
595 struct evtchn_bind_vcpu bind_vcpu
;
596 int evtchn
= evtchn_from_irq(irq
);
598 if (!VALID_EVTCHN(evtchn
))
601 /* Send future instances of this interrupt to other vcpu. */
602 bind_vcpu
.port
= evtchn
;
603 bind_vcpu
.vcpu
= tcpu
;
606 * If this fails, it usually just indicates that we're dealing with a
607 * virq or IPI channel, which don't actually need to be rebound. Ignore
608 * it, but don't do the xenlinux-level rebind in that case.
610 if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_vcpu
, &bind_vcpu
) >= 0)
611 bind_evtchn_to_cpu(evtchn
, tcpu
);
615 static void set_affinity_irq(unsigned irq
, cpumask_t dest
)
617 unsigned tcpu
= first_cpu(dest
);
618 rebind_irq_to_cpu(irq
, tcpu
);
621 int resend_irq_on_evtchn(unsigned int irq
)
623 int masked
, evtchn
= evtchn_from_irq(irq
);
624 struct shared_info
*s
= HYPERVISOR_shared_info
;
626 if (!VALID_EVTCHN(evtchn
))
629 masked
= sync_test_and_set_bit(evtchn
, s
->evtchn_mask
);
630 sync_set_bit(evtchn
, s
->evtchn_pending
);
632 unmask_evtchn(evtchn
);
637 static void enable_dynirq(unsigned int irq
)
639 int evtchn
= evtchn_from_irq(irq
);
641 if (VALID_EVTCHN(evtchn
))
642 unmask_evtchn(evtchn
);
645 static void disable_dynirq(unsigned int irq
)
647 int evtchn
= evtchn_from_irq(irq
);
649 if (VALID_EVTCHN(evtchn
))
653 static void ack_dynirq(unsigned int irq
)
655 int evtchn
= evtchn_from_irq(irq
);
657 move_native_irq(irq
);
659 if (VALID_EVTCHN(evtchn
))
660 clear_evtchn(evtchn
);
663 static int retrigger_dynirq(unsigned int irq
)
665 int evtchn
= evtchn_from_irq(irq
);
666 struct shared_info
*sh
= HYPERVISOR_shared_info
;
669 if (VALID_EVTCHN(evtchn
)) {
672 masked
= sync_test_and_set_bit(evtchn
, sh
->evtchn_mask
);
673 sync_set_bit(evtchn
, sh
->evtchn_pending
);
675 unmask_evtchn(evtchn
);
682 static void restore_cpu_virqs(unsigned int cpu
)
684 struct evtchn_bind_virq bind_virq
;
685 int virq
, irq
, evtchn
;
687 for (virq
= 0; virq
< NR_VIRQS
; virq
++) {
688 if ((irq
= per_cpu(virq_to_irq
, cpu
)[virq
]) == -1)
691 BUG_ON(irq_info
[irq
].type
!= IRQT_VIRQ
);
692 BUG_ON(irq_info
[irq
].index
!= virq
);
694 /* Get a new binding from Xen. */
695 bind_virq
.virq
= virq
;
696 bind_virq
.vcpu
= cpu
;
697 if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_virq
,
700 evtchn
= bind_virq
.port
;
702 /* Record the new mapping. */
703 evtchn_to_irq
[evtchn
] = irq
;
704 irq_info
[irq
] = mk_irq_info(IRQT_VIRQ
, virq
, evtchn
);
705 bind_evtchn_to_cpu(evtchn
, cpu
);
708 unmask_evtchn(evtchn
);
712 static void restore_cpu_ipis(unsigned int cpu
)
714 struct evtchn_bind_ipi bind_ipi
;
715 int ipi
, irq
, evtchn
;
717 for (ipi
= 0; ipi
< XEN_NR_IPIS
; ipi
++) {
718 if ((irq
= per_cpu(ipi_to_irq
, cpu
)[ipi
]) == -1)
721 BUG_ON(irq_info
[irq
].type
!= IRQT_IPI
);
722 BUG_ON(irq_info
[irq
].index
!= ipi
);
724 /* Get a new binding from Xen. */
726 if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_ipi
,
729 evtchn
= bind_ipi
.port
;
731 /* Record the new mapping. */
732 evtchn_to_irq
[evtchn
] = irq
;
733 irq_info
[irq
] = mk_irq_info(IRQT_IPI
, ipi
, evtchn
);
734 bind_evtchn_to_cpu(evtchn
, cpu
);
737 unmask_evtchn(evtchn
);
742 /* Clear an irq's pending state, in preparation for polling on it */
743 void xen_clear_irq_pending(int irq
)
745 int evtchn
= evtchn_from_irq(irq
);
747 if (VALID_EVTCHN(evtchn
))
748 clear_evtchn(evtchn
);
751 void xen_set_irq_pending(int irq
)
753 int evtchn
= evtchn_from_irq(irq
);
755 if (VALID_EVTCHN(evtchn
))
759 bool xen_test_irq_pending(int irq
)
761 int evtchn
= evtchn_from_irq(irq
);
764 if (VALID_EVTCHN(evtchn
))
765 ret
= test_evtchn(evtchn
);
770 /* Poll waiting for an irq to become pending. In the usual case, the
771 irq will be disabled so it won't deliver an interrupt. */
772 void xen_poll_irq(int irq
)
774 evtchn_port_t evtchn
= evtchn_from_irq(irq
);
776 if (VALID_EVTCHN(evtchn
)) {
777 struct sched_poll poll
;
781 set_xen_guest_handle(poll
.ports
, &evtchn
);
783 if (HYPERVISOR_sched_op(SCHEDOP_poll
, &poll
) != 0)
788 void xen_irq_resume(void)
790 unsigned int cpu
, irq
, evtchn
;
792 init_evtchn_cpu_bindings();
794 /* New event-channel space is not 'live' yet. */
795 for (evtchn
= 0; evtchn
< NR_EVENT_CHANNELS
; evtchn
++)
798 /* No IRQ <-> event-channel mappings. */
799 for (irq
= 0; irq
< nr_irqs
; irq
++)
800 irq_info
[irq
].evtchn
= 0; /* zap event-channel binding */
802 for (evtchn
= 0; evtchn
< NR_EVENT_CHANNELS
; evtchn
++)
803 evtchn_to_irq
[evtchn
] = -1;
805 for_each_possible_cpu(cpu
) {
806 restore_cpu_virqs(cpu
);
807 restore_cpu_ipis(cpu
);
811 static struct irq_chip xen_dynamic_chip __read_mostly
= {
813 .mask
= disable_dynirq
,
814 .unmask
= enable_dynirq
,
816 .set_affinity
= set_affinity_irq
,
817 .retrigger
= retrigger_dynirq
,
820 void __init
xen_init_IRQ(void)
824 init_evtchn_cpu_bindings();
826 /* No event channels are 'live' right now. */
827 for (i
= 0; i
< NR_EVENT_CHANNELS
; i
++)
830 /* Dynamic IRQ space is currently unbound. Zero the refcnts. */
831 for (i
= 0; i
< nr_irqs
; i
++)
832 irq_bindcount
[i
] = 0;
834 irq_ctx_init(smp_processor_id());