[mirror_ubuntu-bionic-kernel.git] / kernel / irq / spurious.c

/*
 * linux/kernel/irq/spurious.c
 *
 * Copyright (C) 1992, 1998-2004 Linus Torvalds, Ingo Molnar
 *
 * This file contains spurious interrupt handling.
 */

#include <linux/jiffies.h>
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/kallsyms.h>
#include <linux/interrupt.h>
#include <linux/moduleparam.h>
#include <linux/timer.h>

#include "internals.h"

static int irqfixup __read_mostly;

#define POLL_SPURIOUS_IRQ_INTERVAL (HZ/10)
static void poll_spurious_irqs(unsigned long dummy);
static DEFINE_TIMER(poll_spurious_irq_timer, poll_spurious_irqs, 0, 0);
static int irq_poll_cpu;
static atomic_t irq_poll_active;

/*
 * We wait here for a poller to finish.
 *
 * If the poll runs on this CPU, then we yell loudly and return
 * false. That will leave the interrupt line disabled in the worst
 * case, but it should never happen.
 *
 * We wait until the poller is done and then recheck disabled and
 * action (about to be disabled). Only if it's still active, we return
 * true and let the handler run.
 */
bool irq_wait_for_poll(struct irq_desc *desc)
{
	if (WARN_ONCE(irq_poll_cpu == smp_processor_id(),
		      "irq poll in progress on cpu %d for irq %d\n",
		      smp_processor_id(), desc->irq_data.irq))
		return false;

#ifdef CONFIG_SMP
	do {
		raw_spin_unlock(&desc->lock);
		while (desc->istate & IRQS_INPROGRESS)
			cpu_relax();
		raw_spin_lock(&desc->lock);
	} while (desc->istate & IRQS_INPROGRESS);
	/* Might have been disabled in meantime */
	return !(desc->istate & IRQS_DISABLED) && desc->action;
#else
	return false;
#endif
}


/*
 * Recovery handler for misrouted interrupts.
 */
static int try_one_irq(int irq, struct irq_desc *desc, bool force)
{
	irqreturn_t ret = IRQ_NONE;
	struct irqaction *action;

	raw_spin_lock(&desc->lock);

	/* PER_CPU and nested thread interrupts are never polled */
	if (irq_settings_is_per_cpu(desc) || irq_settings_is_nested_thread(desc))
		goto out;

	/*
	 * Do not poll disabled interrupts unless the spurious
	 * disabled poller asks explicitely.
	 */
	if ((desc->istate & IRQS_DISABLED) && !force)
		goto out;

	/*
	 * All handlers must agree on IRQF_SHARED, so we test just the
	 * first. Check for action->next as well.
	 */
	action = desc->action;
	if (!action || !(action->flags & IRQF_SHARED) ||
	    (action->flags & __IRQF_TIMER) || !action->next)
		goto out;

	/* Already running on another processor */
	if (desc->istate & IRQS_INPROGRESS) {
		/*
		 * Already running: If it is shared get the other
		 * CPU to go looking for our mystery interrupt too
		 */
		irq_compat_set_pending(desc);
		desc->istate |= IRQS_PENDING;
		goto out;
	}

	/* Mark it poll in progress */
	desc->istate |= IRQS_POLL_INPROGRESS;
	do {
		if (handle_irq_event(desc) == IRQ_HANDLED)
			ret = IRQ_HANDLED;
		action = desc->action;
	} while ((desc->istate & IRQS_PENDING) && action);
	desc->istate &= ~IRQS_POLL_INPROGRESS;
out:
	raw_spin_unlock(&desc->lock);
	return ret == IRQ_HANDLED;
}

static int misrouted_irq(int irq)
{
	struct irq_desc *desc;
	int i, ok = 0;

	if (atomic_inc_return(&irq_poll_active) == 1)
		goto out;

	irq_poll_cpu = smp_processor_id();

	for_each_irq_desc(i, desc) {
		if (!i)
			 continue;

		if (i == irq)	/* Already tried */
			continue;

		if (try_one_irq(i, desc, false))
			ok = 1;
	}
out:
	atomic_dec(&irq_poll_active);
	/* So the caller can adjust the irq error counts */
	return ok;
}

static void poll_spurious_irqs(unsigned long dummy)
{
	struct irq_desc *desc;
	int i;

	if (atomic_inc_return(&irq_poll_active) != 1)
		goto out;
	irq_poll_cpu = smp_processor_id();

	for_each_irq_desc(i, desc) {
		unsigned int state;

		if (!i)
			 continue;

		/* Racy but it doesn't matter */
		state = desc->istate;
		barrier();
		if (!(state & IRQS_SPURIOUS_DISABLED))
			continue;

		local_irq_disable();
		try_one_irq(i, desc, true);
		local_irq_enable();
	}
out:
	atomic_dec(&irq_poll_active);
	mod_timer(&poll_spurious_irq_timer,
		  jiffies + POLL_SPURIOUS_IRQ_INTERVAL);
}

/*
 * If 99,900 of the previous 100,000 interrupts have not been handled
 * then assume that the IRQ is stuck in some manner. Drop a diagnostic
 * and try to turn the IRQ off.
 *
 * (The other 100-of-100,000 interrupts may have been a correctly
 *  functioning device sharing an IRQ with the failing one)
 */
static void
__report_bad_irq(unsigned int irq, struct irq_desc *desc,
		 irqreturn_t action_ret)
{
	struct irqaction *action;
	unsigned long flags;

	if (action_ret != IRQ_HANDLED && action_ret != IRQ_NONE) {
		printk(KERN_ERR "irq event %d: bogus return value %x\n",
				irq, action_ret);
	} else {
		printk(KERN_ERR "irq %d: nobody cared (try booting with "
				"the \"irqpoll\" option)\n", irq);
	}
	dump_stack();
	printk(KERN_ERR "handlers:\n");

	/*
	 * We need to take desc->lock here. note_interrupt() is called
	 * w/o desc->lock held, but IRQ_PROGRESS set. We might race
	 * with something else removing an action. It's ok to take
	 * desc->lock here. See synchronize_irq().
	 */
	raw_spin_lock_irqsave(&desc->lock, flags);
	action = desc->action;
	while (action) {
		printk(KERN_ERR "[<%p>]", action->handler);
		print_symbol(" (%s)",
			(unsigned long)action->handler);
		printk("\n");
		action = action->next;
	}
	raw_spin_unlock_irqrestore(&desc->lock, flags);
}

static void
report_bad_irq(unsigned int irq, struct irq_desc *desc, irqreturn_t action_ret)
{
	static int count = 100;

	if (count > 0) {
		count--;
		__report_bad_irq(irq, desc, action_ret);
	}
}

static inline int
try_misrouted_irq(unsigned int irq, struct irq_desc *desc,
		  irqreturn_t action_ret)
{
	struct irqaction *action;

	if (!irqfixup)
		return 0;

	/* We didn't actually handle the IRQ - see if it was misrouted? */
	if (action_ret == IRQ_NONE)
		return 1;

	/*
	 * But for 'irqfixup == 2' we also do it for handled interrupts if
	 * they are marked as IRQF_IRQPOLL (or for irq zero, which is the
	 * traditional PC timer interrupt.. Legacy)
	 */
	if (irqfixup < 2)
		return 0;

	if (!irq)
		return 1;

	/*
	 * Since we don't get the descriptor lock, "action" can
	 * change under us.  We don't really care, but we don't
	 * want to follow a NULL pointer. So tell the compiler to
	 * just load it once by using a barrier.
	 */
	action = desc->action;
	barrier();
	return action && (action->flags & IRQF_IRQPOLL);
}

void note_interrupt(unsigned int irq, struct irq_desc *desc,
		    irqreturn_t action_ret)
{
	if (desc->istate & IRQS_POLL_INPROGRESS)
		return;

	if (unlikely(action_ret != IRQ_HANDLED)) {
		/*
		 * If we are seeing only the odd spurious IRQ caused by
		 * bus asynchronicity then don't eventually trigger an error,
		 * otherwise the counter becomes a doomsday timer for otherwise
		 * working systems
		 */
		if (time_after(jiffies, desc->last_unhandled + HZ/10))
			desc->irqs_unhandled = 1;
		else
			desc->irqs_unhandled++;
		desc->last_unhandled = jiffies;
		if (unlikely(action_ret != IRQ_NONE))
			report_bad_irq(irq, desc, action_ret);
	}

	if (unlikely(try_misrouted_irq(irq, desc, action_ret))) {
		int ok = misrouted_irq(irq);
		if (action_ret == IRQ_NONE)
			desc->irqs_unhandled -= ok;
	}

	desc->irq_count++;
	if (likely(desc->irq_count < 100000))
		return;

	desc->irq_count = 0;
	if (unlikely(desc->irqs_unhandled > 99900)) {
		/*
		 * The interrupt is stuck
		 */
		__report_bad_irq(irq, desc, action_ret);
		/*
		 * Now kill the IRQ
		 */
		printk(KERN_EMERG "Disabling IRQ #%d\n", irq);
		desc->istate |= IRQS_SPURIOUS_DISABLED;
		desc->depth++;
		irq_disable(desc);

		mod_timer(&poll_spurious_irq_timer,
			  jiffies + POLL_SPURIOUS_IRQ_INTERVAL);
	}
	desc->irqs_unhandled = 0;
}

int noirqdebug __read_mostly;

int noirqdebug_setup(char *str)
{
	noirqdebug = 1;
	printk(KERN_INFO "IRQ lockup detection disabled\n");

	return 1;
}

__setup("noirqdebug", noirqdebug_setup);
module_param(noirqdebug, bool, 0644);
MODULE_PARM_DESC(noirqdebug, "Disable irq lockup detection when true");

static int __init irqfixup_setup(char *str)
{
	irqfixup = 1;
	printk(KERN_WARNING "Misrouted IRQ fixup support enabled.\n");
	printk(KERN_WARNING "This may impact system performance.\n");

	return 1;
}

__setup("irqfixup", irqfixup_setup);
module_param(irqfixup, int, 0644);

static int __init irqpoll_setup(char *str)
{
	irqfixup = 2;
	printk(KERN_WARNING "Misrouted IRQ fixup and polling support "
				"enabled\n");
	printk(KERN_WARNING "This may significantly impact system "
				"performance\n");
	return 1;
}

__setup("irqpoll", irqpoll_setup);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/kernel/irq/spurious.c
	3	*
	4	* Copyright (C) 1992, 1998-2004 Linus Torvalds, Ingo Molnar
	5	*
	6	* This file contains spurious interrupt handling.
	7	*/
	8
188fd89d	9	#include <linux/jiffies.h>
1da177e4 LT	10	#include <linux/irq.h>
	11	#include <linux/module.h>
	12	#include <linux/kallsyms.h>
	13	#include <linux/interrupt.h>
9e094c17	14	#include <linux/moduleparam.h>
f84dbb91	15	#include <linux/timer.h>
1da177e4	16
bd151412 TG	17	#include "internals.h"
bd151412 TG	18
83d4e6e7	19	static int irqfixup __read_mostly;
200803df	20
f84dbb91 EB	21	#define POLL_SPURIOUS_IRQ_INTERVAL (HZ/10)
	22	static void poll_spurious_irqs(unsigned long dummy);
	23	static DEFINE_TIMER(poll_spurious_irq_timer, poll_spurious_irqs, 0, 0);
d05c65ff TG	24	static int irq_poll_cpu;
d05c65ff TG	25	static atomic_t irq_poll_active;
f84dbb91	26
fe200ae4 TG	27	/*
	28	* We wait here for a poller to finish.
	29	*
	30	* If the poll runs on this CPU, then we yell loudly and return
	31	* false. That will leave the interrupt line disabled in the worst
	32	* case, but it should never happen.
	33	*
	34	* We wait until the poller is done and then recheck disabled and
	35	* action (about to be disabled). Only if it's still active, we return
	36	* true and let the handler run.
	37	*/
	38	bool irq_wait_for_poll(struct irq_desc *desc)
	39	{
	40	if (WARN_ONCE(irq_poll_cpu == smp_processor_id(),
	41	"irq poll in progress on cpu %d for irq %d\n",
	42	smp_processor_id(), desc->irq_data.irq))
	43	return false;
	44
	45	#ifdef CONFIG_SMP
	46	do {
	47	raw_spin_unlock(&desc->lock);
009b4c3b	48	while (desc->istate & IRQS_INPROGRESS)
fe200ae4 TG	49	cpu_relax();
fe200ae4 TG	50	raw_spin_lock(&desc->lock);
009b4c3b	51	} while (desc->istate & IRQS_INPROGRESS);
fe200ae4	52	/* Might have been disabled in meantime */
c1594b77	53	return !(desc->istate & IRQS_DISABLED) && desc->action;
fe200ae4 TG	54	#else
	55	return false;
	56	#endif
	57	}
	58
0877d662	59
200803df AC	60	/*
	61	* Recovery handler for misrouted interrupts.
	62	*/
c7259cd7	63	static int try_one_irq(int irq, struct irq_desc *desc, bool force)
200803df	64	{
0877d662	65	irqreturn_t ret = IRQ_NONE;
f84dbb91	66	struct irqaction *action;
200803df	67
239007b8	68	raw_spin_lock(&desc->lock);
c7259cd7 TG	69
c7259cd7 TG	70	/* PER_CPU and nested thread interrupts are never polled */
1ccb4e61	71	if (irq_settings_is_per_cpu(desc) \|\| irq_settings_is_nested_thread(desc))
c7259cd7 TG	72	goto out;
	73
	74	/*
	75	* Do not poll disabled interrupts unless the spurious
	76	* disabled poller asks explicitely.
	77	*/
c1594b77	78	if ((desc->istate & IRQS_DISABLED) && !force)
c7259cd7 TG	79	goto out;
	80
	81	/*
	82	* All handlers must agree on IRQF_SHARED, so we test just the
	83	* first. Check for action->next as well.
	84	*/
	85	action = desc->action;
	86	if (!action \|\| !(action->flags & IRQF_SHARED) \|\|
	87	(action->flags & __IRQF_TIMER) \|\| !action->next)
	88	goto out;
	89
f84dbb91	90	/* Already running on another processor */
009b4c3b	91	if (desc->istate & IRQS_INPROGRESS) {
f84dbb91 EB	92	/*
	93	* Already running: If it is shared get the other
	94	* CPU to go looking for our mystery interrupt too
	95	*/
2a0d6fb3 TG	96	irq_compat_set_pending(desc);
2a0d6fb3 TG	97	desc->istate \|= IRQS_PENDING;
fa27271b	98	goto out;
c7259cd7	99	}
fa27271b	100
0877d662	101	/* Mark it poll in progress */
6954b75b	102	desc->istate \|= IRQS_POLL_INPROGRESS;
fa27271b	103	do {
0877d662 TG	104	if (handle_irq_event(desc) == IRQ_HANDLED)
0877d662 TG	105	ret = IRQ_HANDLED;
fa27271b	106	action = desc->action;
2a0d6fb3	107	} while ((desc->istate & IRQS_PENDING) && action);
6954b75b	108	desc->istate &= ~IRQS_POLL_INPROGRESS;
fa27271b TG	109	out:
fa27271b TG	110	raw_spin_unlock(&desc->lock);
0877d662	111	return ret == IRQ_HANDLED;
f84dbb91 EB	112	}
	113
	114	static int misrouted_irq(int irq)
	115	{
e00585bb	116	struct irq_desc *desc;
d3c60047	117	int i, ok = 0;
f84dbb91	118
d05c65ff TG	119	if (atomic_inc_return(&irq_poll_active) == 1)
	120	goto out;
	121
	122	irq_poll_cpu = smp_processor_id();
	123
e00585bb YL	124	for_each_irq_desc(i, desc) {
	125	if (!i)
	126	continue;
f84dbb91 EB	127
	128	if (i == irq) /* Already tried */
	129	continue;
	130
c7259cd7	131	if (try_one_irq(i, desc, false))
f84dbb91	132	ok = 1;
200803df	133	}
d05c65ff TG	134	out:
d05c65ff TG	135	atomic_dec(&irq_poll_active);
200803df AC	136	/* So the caller can adjust the irq error counts */
	137	return ok;
	138	}
	139
663e6959	140	static void poll_spurious_irqs(unsigned long dummy)
f84dbb91	141	{
e00585bb	142	struct irq_desc *desc;
d3c60047	143	int i;
e00585bb	144
d05c65ff TG	145	if (atomic_inc_return(&irq_poll_active) != 1)
	146	goto out;
	147	irq_poll_cpu = smp_processor_id();
	148
e00585bb	149	for_each_irq_desc(i, desc) {
7acdd53e	150	unsigned int state;
f84dbb91	151
e00585bb YL	152	if (!i)
	153	continue;
	154
f84dbb91	155	/* Racy but it doesn't matter */
7acdd53e	156	state = desc->istate;
f84dbb91	157	barrier();
7acdd53e	158	if (!(state & IRQS_SPURIOUS_DISABLED))
f84dbb91 EB	159	continue;
f84dbb91 EB	160
e7e7e0c0	161	local_irq_disable();
c7259cd7	162	try_one_irq(i, desc, true);
e7e7e0c0	163	local_irq_enable();
f84dbb91	164	}
d05c65ff TG	165	out:
d05c65ff TG	166	atomic_dec(&irq_poll_active);
d3c60047 TG	167	mod_timer(&poll_spurious_irq_timer,
d3c60047 TG	168	jiffies + POLL_SPURIOUS_IRQ_INTERVAL);
f84dbb91 EB	169	}
f84dbb91 EB	170
1da177e4 LT	171	/*
	172	* If 99,900 of the previous 100,000 interrupts have not been handled
	173	* then assume that the IRQ is stuck in some manner. Drop a diagnostic
	174	* and try to turn the IRQ off.
	175	*
	176	* (The other 100-of-100,000 interrupts may have been a correctly
	177	* functioning device sharing an IRQ with the failing one)
1da177e4	178	*/
1da177e4	179	static void
34ffdb72 IM	180	__report_bad_irq(unsigned int irq, struct irq_desc *desc,
34ffdb72 IM	181	irqreturn_t action_ret)
1da177e4 LT	182	{
1da177e4 LT	183	struct irqaction *action;
1082687e	184	unsigned long flags;
1da177e4 LT	185
	186	if (action_ret != IRQ_HANDLED && action_ret != IRQ_NONE) {
	187	printk(KERN_ERR "irq event %d: bogus return value %x\n",
	188	irq, action_ret);
	189	} else {
200803df AC	190	printk(KERN_ERR "irq %d: nobody cared (try booting with "
200803df AC	191	"the \"irqpoll\" option)\n", irq);
1da177e4 LT	192	}
	193	dump_stack();
	194	printk(KERN_ERR "handlers:\n");
06fcb0c6	195
1082687e TG	196	/*
	197	* We need to take desc->lock here. note_interrupt() is called
	198	* w/o desc->lock held, but IRQ_PROGRESS set. We might race
	199	* with something else removing an action. It's ok to take
	200	* desc->lock here. See synchronize_irq().
	201	*/
	202	raw_spin_lock_irqsave(&desc->lock, flags);
1da177e4 LT	203	action = desc->action;
	204	while (action) {
	205	printk(KERN_ERR "[<%p>]", action->handler);
	206	print_symbol(" (%s)",
	207	(unsigned long)action->handler);
	208	printk("\n");
	209	action = action->next;
	210	}
1082687e	211	raw_spin_unlock_irqrestore(&desc->lock, flags);
1da177e4 LT	212	}
1da177e4 LT	213
06fcb0c6	214	static void
34ffdb72	215	report_bad_irq(unsigned int irq, struct irq_desc *desc, irqreturn_t action_ret)
1da177e4 LT	216	{
	217	static int count = 100;
	218
	219	if (count > 0) {
	220	count--;
	221	__report_bad_irq(irq, desc, action_ret);
	222	}
	223	}
	224
d3c60047 TG	225	static inline int
	226	try_misrouted_irq(unsigned int irq, struct irq_desc *desc,
	227	irqreturn_t action_ret)
92ea7727 LT	228	{
	229	struct irqaction *action;
	230
	231	if (!irqfixup)
	232	return 0;
	233
	234	/* We didn't actually handle the IRQ - see if it was misrouted? */
	235	if (action_ret == IRQ_NONE)
	236	return 1;
	237
	238	/*
	239	* But for 'irqfixup == 2' we also do it for handled interrupts if
	240	* they are marked as IRQF_IRQPOLL (or for irq zero, which is the
	241	* traditional PC timer interrupt.. Legacy)
	242	*/
	243	if (irqfixup < 2)
	244	return 0;
	245
	246	if (!irq)
	247	return 1;
	248
	249	/*
	250	* Since we don't get the descriptor lock, "action" can
	251	* change under us. We don't really care, but we don't
	252	* want to follow a NULL pointer. So tell the compiler to
	253	* just load it once by using a barrier.
	254	*/
	255	action = desc->action;
	256	barrier();
	257	return action && (action->flags & IRQF_IRQPOLL);
	258	}
	259
34ffdb72	260	void note_interrupt(unsigned int irq, struct irq_desc *desc,
7d12e780	261	irqreturn_t action_ret)
1da177e4	262	{
6954b75b	263	if (desc->istate & IRQS_POLL_INPROGRESS)
fe200ae4 TG	264	return;
fe200ae4 TG	265
83d4e6e7	266	if (unlikely(action_ret != IRQ_HANDLED)) {
4f27c00b AC	267	/*
	268	* If we are seeing only the odd spurious IRQ caused by
	269	* bus asynchronicity then don't eventually trigger an error,
fbfecd37	270	* otherwise the counter becomes a doomsday timer for otherwise
4f27c00b AC	271	* working systems
4f27c00b AC	272	*/
188fd89d	273	if (time_after(jiffies, desc->last_unhandled + HZ/10))
4f27c00b AC	274	desc->irqs_unhandled = 1;
	275	else
	276	desc->irqs_unhandled++;
	277	desc->last_unhandled = jiffies;
83d4e6e7	278	if (unlikely(action_ret != IRQ_NONE))
1da177e4 LT	279	report_bad_irq(irq, desc, action_ret);
	280	}
	281
92ea7727 LT	282	if (unlikely(try_misrouted_irq(irq, desc, action_ret))) {
	283	int ok = misrouted_irq(irq);
	284	if (action_ret == IRQ_NONE)
	285	desc->irqs_unhandled -= ok;
200803df AC	286	}
200803df AC	287
1da177e4	288	desc->irq_count++;
83d4e6e7	289	if (likely(desc->irq_count < 100000))
1da177e4 LT	290	return;
	291
	292	desc->irq_count = 0;
83d4e6e7	293	if (unlikely(desc->irqs_unhandled > 99900)) {
1da177e4 LT	294	/*
	295	* The interrupt is stuck
	296	*/
	297	__report_bad_irq(irq, desc, action_ret);
	298	/*
	299	* Now kill the IRQ
	300	*/
	301	printk(KERN_EMERG "Disabling IRQ #%d\n", irq);
7acdd53e	302	desc->istate \|= IRQS_SPURIOUS_DISABLED;
1adb0850	303	desc->depth++;
87923470	304	irq_disable(desc);
f84dbb91	305
d3c60047 TG	306	mod_timer(&poll_spurious_irq_timer,
d3c60047 TG	307	jiffies + POLL_SPURIOUS_IRQ_INTERVAL);
1da177e4 LT	308	}
	309	desc->irqs_unhandled = 0;
	310	}
	311
83d4e6e7	312	int noirqdebug __read_mostly;
1da177e4	313
343cde51	314	int noirqdebug_setup(char *str)
1da177e4 LT	315	{
	316	noirqdebug = 1;
	317	printk(KERN_INFO "IRQ lockup detection disabled\n");
06fcb0c6	318
1da177e4 LT	319	return 1;
	320	}
	321
	322	__setup("noirqdebug", noirqdebug_setup);
9e094c17 AK	323	module_param(noirqdebug, bool, 0644);
9e094c17 AK	324	MODULE_PARM_DESC(noirqdebug, "Disable irq lockup detection when true");
1da177e4	325
200803df AC	326	static int __init irqfixup_setup(char *str)
	327	{
	328	irqfixup = 1;
	329	printk(KERN_WARNING "Misrouted IRQ fixup support enabled.\n");
	330	printk(KERN_WARNING "This may impact system performance.\n");
06fcb0c6	331
200803df AC	332	return 1;
	333	}
	334
	335	__setup("irqfixup", irqfixup_setup);
9e094c17	336	module_param(irqfixup, int, 0644);
200803df AC	337
	338	static int __init irqpoll_setup(char *str)
	339	{
	340	irqfixup = 2;
	341	printk(KERN_WARNING "Misrouted IRQ fixup and polling support "
	342	"enabled\n");
	343	printk(KERN_WARNING "This may significantly impact system "
	344	"performance\n");
	345	return 1;
	346	}
	347
	348	__setup("irqpoll", irqpoll_setup);