[net-next-2.6.git] / fs / eventfd.c

/*
 *  fs/eventfd.c
 *
 *  Copyright (C) 2007  Davide Libenzi <davidel@xmailserver.org>
 *
 */

#include <linux/file.h>
#include <linux/poll.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/spinlock.h>
#include <linux/anon_inodes.h>
#include <linux/syscalls.h>
#include <linux/module.h>
#include <linux/kref.h>
#include <linux/eventfd.h>

struct eventfd_ctx {
	struct kref kref;
	wait_queue_head_t wqh;
	/*
	 * Every time that a write(2) is performed on an eventfd, the
	 * value of the __u64 being written is added to "count" and a
	 * wakeup is performed on "wqh". A read(2) will return the "count"
	 * value to userspace, and will reset "count" to zero. The kernel
	 * side eventfd_signal() also, adds to the "count" counter and
	 * issue a wakeup.
	 */
	__u64 count;
	unsigned int flags;
};

/**
 * eventfd_signal - Adds @n to the eventfd counter.
 * @ctx: [in] Pointer to the eventfd context.
 * @n: [in] Value of the counter to be added to the eventfd internal counter.
 *          The value cannot be negative.
 *
 * This function is supposed to be called by the kernel in paths that do not
 * allow sleeping. In this function we allow the counter to reach the ULLONG_MAX
 * value, and we signal this as overflow condition by returining a POLLERR
 * to poll(2).
 *
 * Returns @n in case of success, a non-negative number lower than @n in case
 * of overflow, or the following error codes:
 *
 * -EINVAL    : The value of @n is negative.
 */
int eventfd_signal(struct eventfd_ctx *ctx, int n)
{
	unsigned long flags;

	if (n < 0)
		return -EINVAL;
	spin_lock_irqsave(&ctx->wqh.lock, flags);
	if (ULLONG_MAX - ctx->count < n)
		n = (int) (ULLONG_MAX - ctx->count);
	ctx->count += n;
	if (waitqueue_active(&ctx->wqh))
		wake_up_locked_poll(&ctx->wqh, POLLIN);
	spin_unlock_irqrestore(&ctx->wqh.lock, flags);

	return n;
}
EXPORT_SYMBOL_GPL(eventfd_signal);

static void eventfd_free(struct kref *kref)
{
	struct eventfd_ctx *ctx = container_of(kref, struct eventfd_ctx, kref);

	kfree(ctx);
}

/**
 * eventfd_ctx_get - Acquires a reference to the internal eventfd context.
 * @ctx: [in] Pointer to the eventfd context.
 *
 * Returns: In case of success, returns a pointer to the eventfd context.
 */
struct eventfd_ctx *eventfd_ctx_get(struct eventfd_ctx *ctx)
{
	kref_get(&ctx->kref);
	return ctx;
}
EXPORT_SYMBOL_GPL(eventfd_ctx_get);

/**
 * eventfd_ctx_put - Releases a reference to the internal eventfd context.
 * @ctx: [in] Pointer to eventfd context.
 *
 * The eventfd context reference must have been previously acquired either
 * with eventfd_ctx_get() or eventfd_ctx_fdget()).
 */
void eventfd_ctx_put(struct eventfd_ctx *ctx)
{
	kref_put(&ctx->kref, eventfd_free);
}
EXPORT_SYMBOL_GPL(eventfd_ctx_put);

static int eventfd_release(struct inode *inode, struct file *file)
{
	struct eventfd_ctx *ctx = file->private_data;

	wake_up_poll(&ctx->wqh, POLLHUP);
	eventfd_ctx_put(ctx);
	return 0;
}

static unsigned int eventfd_poll(struct file *file, poll_table *wait)
{
	struct eventfd_ctx *ctx = file->private_data;
	unsigned int events = 0;
	unsigned long flags;

	poll_wait(file, &ctx->wqh, wait);

	spin_lock_irqsave(&ctx->wqh.lock, flags);
	if (ctx->count > 0)
		events |= POLLIN;
	if (ctx->count == ULLONG_MAX)
		events |= POLLERR;
	if (ULLONG_MAX - 1 > ctx->count)
		events |= POLLOUT;
	spin_unlock_irqrestore(&ctx->wqh.lock, flags);

	return events;
}

static ssize_t eventfd_read(struct file *file, char __user *buf, size_t count,
			    loff_t *ppos)
{
	struct eventfd_ctx *ctx = file->private_data;
	ssize_t res;
	__u64 ucnt = 0;
	DECLARE_WAITQUEUE(wait, current);

	if (count < sizeof(ucnt))
		return -EINVAL;
	spin_lock_irq(&ctx->wqh.lock);
	res = -EAGAIN;
	if (ctx->count > 0)
		res = sizeof(ucnt);
	else if (!(file->f_flags & O_NONBLOCK)) {
		__add_wait_queue(&ctx->wqh, &wait);
		for (res = 0;;) {
			set_current_state(TASK_INTERRUPTIBLE);
			if (ctx->count > 0) {
				res = sizeof(ucnt);
				break;
			}
			if (signal_pending(current)) {
				res = -ERESTARTSYS;
				break;
			}
			spin_unlock_irq(&ctx->wqh.lock);
			schedule();
			spin_lock_irq(&ctx->wqh.lock);
		}
		__remove_wait_queue(&ctx->wqh, &wait);
		__set_current_state(TASK_RUNNING);
	}
	if (likely(res > 0)) {
		ucnt = (ctx->flags & EFD_SEMAPHORE) ? 1 : ctx->count;
		ctx->count -= ucnt;
		if (waitqueue_active(&ctx->wqh))
			wake_up_locked_poll(&ctx->wqh, POLLOUT);
	}
	spin_unlock_irq(&ctx->wqh.lock);
	if (res > 0 && put_user(ucnt, (__u64 __user *) buf))
		return -EFAULT;

	return res;
}

static ssize_t eventfd_write(struct file *file, const char __user *buf, size_t count,
			     loff_t *ppos)
{
	struct eventfd_ctx *ctx = file->private_data;
	ssize_t res;
	__u64 ucnt;
	DECLARE_WAITQUEUE(wait, current);

	if (count < sizeof(ucnt))
		return -EINVAL;
	if (copy_from_user(&ucnt, buf, sizeof(ucnt)))
		return -EFAULT;
	if (ucnt == ULLONG_MAX)
		return -EINVAL;
	spin_lock_irq(&ctx->wqh.lock);
	res = -EAGAIN;
	if (ULLONG_MAX - ctx->count > ucnt)
		res = sizeof(ucnt);
	else if (!(file->f_flags & O_NONBLOCK)) {
		__add_wait_queue(&ctx->wqh, &wait);
		for (res = 0;;) {
			set_current_state(TASK_INTERRUPTIBLE);
			if (ULLONG_MAX - ctx->count > ucnt) {
				res = sizeof(ucnt);
				break;
			}
			if (signal_pending(current)) {
				res = -ERESTARTSYS;
				break;
			}
			spin_unlock_irq(&ctx->wqh.lock);
			schedule();
			spin_lock_irq(&ctx->wqh.lock);
		}
		__remove_wait_queue(&ctx->wqh, &wait);
		__set_current_state(TASK_RUNNING);
	}
	if (likely(res > 0)) {
		ctx->count += ucnt;
		if (waitqueue_active(&ctx->wqh))
			wake_up_locked_poll(&ctx->wqh, POLLIN);
	}
	spin_unlock_irq(&ctx->wqh.lock);

	return res;
}

static const struct file_operations eventfd_fops = {
	.release	= eventfd_release,
	.poll		= eventfd_poll,
	.read		= eventfd_read,
	.write		= eventfd_write,
};

/**
 * eventfd_fget - Acquire a reference of an eventfd file descriptor.
 * @fd: [in] Eventfd file descriptor.
 *
 * Returns a pointer to the eventfd file structure in case of success, or the
 * following error pointer:
 *
 * -EBADF    : Invalid @fd file descriptor.
 * -EINVAL   : The @fd file descriptor is not an eventfd file.
 */
struct file *eventfd_fget(int fd)
{
	struct file *file;

	file = fget(fd);
	if (!file)
		return ERR_PTR(-EBADF);
	if (file->f_op != &eventfd_fops) {
		fput(file);
		return ERR_PTR(-EINVAL);
	}

	return file;
}
EXPORT_SYMBOL_GPL(eventfd_fget);

/**
 * eventfd_ctx_fdget - Acquires a reference to the internal eventfd context.
 * @fd: [in] Eventfd file descriptor.
 *
 * Returns a pointer to the internal eventfd context, otherwise the error
 * pointers returned by the following functions:
 *
 * eventfd_fget
 */
struct eventfd_ctx *eventfd_ctx_fdget(int fd)
{
	struct file *file;
	struct eventfd_ctx *ctx;

	file = eventfd_fget(fd);
	if (IS_ERR(file))
		return (struct eventfd_ctx *) file;
	ctx = eventfd_ctx_get(file->private_data);
	fput(file);

	return ctx;
}
EXPORT_SYMBOL_GPL(eventfd_ctx_fdget);

/**
 * eventfd_ctx_fileget - Acquires a reference to the internal eventfd context.
 * @file: [in] Eventfd file pointer.
 *
 * Returns a pointer to the internal eventfd context, otherwise the error
 * pointer:
 *
 * -EINVAL   : The @fd file descriptor is not an eventfd file.
 */
struct eventfd_ctx *eventfd_ctx_fileget(struct file *file)
{
	if (file->f_op != &eventfd_fops)
		return ERR_PTR(-EINVAL);

	return eventfd_ctx_get(file->private_data);
}
EXPORT_SYMBOL_GPL(eventfd_ctx_fileget);

SYSCALL_DEFINE2(eventfd2, unsigned int, count, int, flags)
{
	int fd;
	struct eventfd_ctx *ctx;

	/* Check the EFD_* constants for consistency.  */
	BUILD_BUG_ON(EFD_CLOEXEC != O_CLOEXEC);
	BUILD_BUG_ON(EFD_NONBLOCK != O_NONBLOCK);

	if (flags & ~EFD_FLAGS_SET)
		return -EINVAL;

	ctx = kmalloc(sizeof(*ctx), GFP_KERNEL);
	if (!ctx)
		return -ENOMEM;

	kref_init(&ctx->kref);
	init_waitqueue_head(&ctx->wqh);
	ctx->count = count;
	ctx->flags = flags;

	/*
	 * When we call this, the initialization must be complete, since
	 * anon_inode_getfd() will install the fd.
	 */
	fd = anon_inode_getfd("[eventfd]", &eventfd_fops, ctx,
			      flags & EFD_SHARED_FCNTL_FLAGS);
	if (fd < 0)
		kfree(ctx);
	return fd;
}

SYSCALL_DEFINE1(eventfd, unsigned int, count)
{
	return sys_eventfd2(count, 0);
}
Commit	Line	Data
e1ad7468 DL	1	/*
	2	* fs/eventfd.c
	3	*
	4	* Copyright (C) 2007 Davide Libenzi <davidel@xmailserver.org>
	5	*
	6	*/
	7
	8	#include <linux/file.h>
	9	#include <linux/poll.h>
	10	#include <linux/init.h>
	11	#include <linux/fs.h>
	12	#include <linux/sched.h>
	13	#include <linux/kernel.h>
	14	#include <linux/list.h>
	15	#include <linux/spinlock.h>
	16	#include <linux/anon_inodes.h>
7747cdb2	17	#include <linux/syscalls.h>
5718607b	18	#include <linux/module.h>
13389010 DL	19	#include <linux/kref.h>
13389010 DL	20	#include <linux/eventfd.h>
e1ad7468 DL	21
e1ad7468 DL	22	struct eventfd_ctx {
13389010	23	struct kref kref;
e1ad7468 DL	24	wait_queue_head_t wqh;
	25	/*
	26	* Every time that a write(2) is performed on an eventfd, the
	27	* value of the __u64 being written is added to "count" and a
	28	* wakeup is performed on "wqh". A read(2) will return the "count"
	29	* value to userspace, and will reset "count" to zero. The kernel
13389010	30	* side eventfd_signal() also, adds to the "count" counter and
e1ad7468 DL	31	* issue a wakeup.
	32	*/
	33	__u64 count;
bcd0b235	34	unsigned int flags;
e1ad7468 DL	35	};
e1ad7468 DL	36
13389010 DL	37	/**
	38	* eventfd_signal - Adds @n to the eventfd counter.
	39	* @ctx: [in] Pointer to the eventfd context.
	40	* @n: [in] Value of the counter to be added to the eventfd internal counter.
	41	* The value cannot be negative.
	42	*
	43	* This function is supposed to be called by the kernel in paths that do not
	44	* allow sleeping. In this function we allow the counter to reach the ULLONG_MAX
	45	* value, and we signal this as overflow condition by returining a POLLERR
	46	* to poll(2).
	47	*
	48	* Returns @n in case of success, a non-negative number lower than @n in case
	49	* of overflow, or the following error codes:
	50	*
	51	* -EINVAL : The value of @n is negative.
e1ad7468	52	*/
13389010	53	int eventfd_signal(struct eventfd_ctx *ctx, int n)
e1ad7468	54	{
e1ad7468 DL	55	unsigned long flags;
	56
	57	if (n < 0)
	58	return -EINVAL;
d48eb233	59	spin_lock_irqsave(&ctx->wqh.lock, flags);
e1ad7468 DL	60	if (ULLONG_MAX - ctx->count < n)
	61	n = (int) (ULLONG_MAX - ctx->count);
	62	ctx->count += n;
	63	if (waitqueue_active(&ctx->wqh))
39510888	64	wake_up_locked_poll(&ctx->wqh, POLLIN);
d48eb233	65	spin_unlock_irqrestore(&ctx->wqh.lock, flags);
e1ad7468 DL	66
	67	return n;
	68	}
5718607b	69	EXPORT_SYMBOL_GPL(eventfd_signal);
e1ad7468	70
13389010 DL	71	static void eventfd_free(struct kref *kref)
	72	{
	73	struct eventfd_ctx *ctx = container_of(kref, struct eventfd_ctx, kref);
	74
	75	kfree(ctx);
	76	}
	77
	78	/**
	79	* eventfd_ctx_get - Acquires a reference to the internal eventfd context.
	80	* @ctx: [in] Pointer to the eventfd context.
	81	*
	82	* Returns: In case of success, returns a pointer to the eventfd context.
	83	*/
	84	struct eventfd_ctx eventfd_ctx_get(struct eventfd_ctx ctx)
	85	{
	86	kref_get(&ctx->kref);
	87	return ctx;
	88	}
	89	EXPORT_SYMBOL_GPL(eventfd_ctx_get);
	90
	91	/**
	92	* eventfd_ctx_put - Releases a reference to the internal eventfd context.
	93	* @ctx: [in] Pointer to eventfd context.
	94	*
	95	* The eventfd context reference must have been previously acquired either
	96	* with eventfd_ctx_get() or eventfd_ctx_fdget()).
	97	*/
	98	void eventfd_ctx_put(struct eventfd_ctx *ctx)
	99	{
	100	kref_put(&ctx->kref, eventfd_free);
	101	}
	102	EXPORT_SYMBOL_GPL(eventfd_ctx_put);
	103
e1ad7468 DL	104	static int eventfd_release(struct inode inode, struct file file)
e1ad7468 DL	105	{
13389010 DL	106	struct eventfd_ctx *ctx = file->private_data;
	107
	108	wake_up_poll(&ctx->wqh, POLLHUP);
	109	eventfd_ctx_put(ctx);
e1ad7468 DL	110	return 0;
	111	}
	112
	113	static unsigned int eventfd_poll(struct file file, poll_table wait)
	114	{
	115	struct eventfd_ctx *ctx = file->private_data;
	116	unsigned int events = 0;
	117	unsigned long flags;
	118
	119	poll_wait(file, &ctx->wqh, wait);
	120
d48eb233	121	spin_lock_irqsave(&ctx->wqh.lock, flags);
e1ad7468 DL	122	if (ctx->count > 0)
	123	events \|= POLLIN;
	124	if (ctx->count == ULLONG_MAX)
	125	events \|= POLLERR;
	126	if (ULLONG_MAX - 1 > ctx->count)
	127	events \|= POLLOUT;
d48eb233	128	spin_unlock_irqrestore(&ctx->wqh.lock, flags);
e1ad7468 DL	129
	130	return events;
	131	}
	132
	133	static ssize_t eventfd_read(struct file file, char __user buf, size_t count,
	134	loff_t *ppos)
	135	{
	136	struct eventfd_ctx *ctx = file->private_data;
	137	ssize_t res;
bcd0b235	138	__u64 ucnt = 0;
e1ad7468 DL	139	DECLARE_WAITQUEUE(wait, current);
	140
	141	if (count < sizeof(ucnt))
	142	return -EINVAL;
d48eb233	143	spin_lock_irq(&ctx->wqh.lock);
e1ad7468	144	res = -EAGAIN;
bcd0b235	145	if (ctx->count > 0)
e1ad7468 DL	146	res = sizeof(ucnt);
	147	else if (!(file->f_flags & O_NONBLOCK)) {
	148	__add_wait_queue(&ctx->wqh, &wait);
	149	for (res = 0;;) {
	150	set_current_state(TASK_INTERRUPTIBLE);
	151	if (ctx->count > 0) {
e1ad7468 DL	152	res = sizeof(ucnt);
	153	break;
	154	}
	155	if (signal_pending(current)) {
	156	res = -ERESTARTSYS;
	157	break;
	158	}
d48eb233	159	spin_unlock_irq(&ctx->wqh.lock);
e1ad7468	160	schedule();
d48eb233	161	spin_lock_irq(&ctx->wqh.lock);
e1ad7468 DL	162	}
	163	__remove_wait_queue(&ctx->wqh, &wait);
	164	__set_current_state(TASK_RUNNING);
	165	}
bcd0b235 DL	166	if (likely(res > 0)) {
	167	ucnt = (ctx->flags & EFD_SEMAPHORE) ? 1 : ctx->count;
	168	ctx->count -= ucnt;
e1ad7468	169	if (waitqueue_active(&ctx->wqh))
39510888	170	wake_up_locked_poll(&ctx->wqh, POLLOUT);
e1ad7468	171	}
d48eb233	172	spin_unlock_irq(&ctx->wqh.lock);
e1ad7468 DL	173	if (res > 0 && put_user(ucnt, (__u64 __user *) buf))
	174	return -EFAULT;
	175
	176	return res;
	177	}
	178
	179	static ssize_t eventfd_write(struct file file, const char __user buf, size_t count,
	180	loff_t *ppos)
	181	{
	182	struct eventfd_ctx *ctx = file->private_data;
	183	ssize_t res;
	184	__u64 ucnt;
	185	DECLARE_WAITQUEUE(wait, current);
	186
	187	if (count < sizeof(ucnt))
	188	return -EINVAL;
	189	if (copy_from_user(&ucnt, buf, sizeof(ucnt)))
	190	return -EFAULT;
	191	if (ucnt == ULLONG_MAX)
	192	return -EINVAL;
d48eb233	193	spin_lock_irq(&ctx->wqh.lock);
e1ad7468 DL	194	res = -EAGAIN;
	195	if (ULLONG_MAX - ctx->count > ucnt)
	196	res = sizeof(ucnt);
	197	else if (!(file->f_flags & O_NONBLOCK)) {
	198	__add_wait_queue(&ctx->wqh, &wait);
	199	for (res = 0;;) {
	200	set_current_state(TASK_INTERRUPTIBLE);
	201	if (ULLONG_MAX - ctx->count > ucnt) {
	202	res = sizeof(ucnt);
	203	break;
	204	}
	205	if (signal_pending(current)) {
	206	res = -ERESTARTSYS;
	207	break;
	208	}
d48eb233	209	spin_unlock_irq(&ctx->wqh.lock);
e1ad7468	210	schedule();
d48eb233	211	spin_lock_irq(&ctx->wqh.lock);
e1ad7468 DL	212	}
	213	__remove_wait_queue(&ctx->wqh, &wait);
	214	__set_current_state(TASK_RUNNING);
	215	}
bcd0b235	216	if (likely(res > 0)) {
e1ad7468 DL	217	ctx->count += ucnt;
e1ad7468 DL	218	if (waitqueue_active(&ctx->wqh))
39510888	219	wake_up_locked_poll(&ctx->wqh, POLLIN);
e1ad7468	220	}
d48eb233	221	spin_unlock_irq(&ctx->wqh.lock);
e1ad7468 DL	222
	223	return res;
	224	}
	225
	226	static const struct file_operations eventfd_fops = {
	227	.release = eventfd_release,
	228	.poll = eventfd_poll,
	229	.read = eventfd_read,
	230	.write = eventfd_write,
	231	};
	232
13389010 DL	233	/**
	234	* eventfd_fget - Acquire a reference of an eventfd file descriptor.
	235	* @fd: [in] Eventfd file descriptor.
	236	*
	237	* Returns a pointer to the eventfd file structure in case of success, or the
	238	* following error pointer:
	239	*
	240	* -EBADF : Invalid @fd file descriptor.
	241	* -EINVAL : The @fd file descriptor is not an eventfd file.
	242	*/
e1ad7468 DL	243	struct file *eventfd_fget(int fd)
	244	{
	245	struct file *file;
	246
	247	file = fget(fd);
	248	if (!file)
	249	return ERR_PTR(-EBADF);
	250	if (file->f_op != &eventfd_fops) {
	251	fput(file);
	252	return ERR_PTR(-EINVAL);
	253	}
	254
	255	return file;
	256	}
5718607b	257	EXPORT_SYMBOL_GPL(eventfd_fget);
e1ad7468	258
13389010 DL	259	/**
	260	* eventfd_ctx_fdget - Acquires a reference to the internal eventfd context.
	261	* @fd: [in] Eventfd file descriptor.
	262	*
	263	* Returns a pointer to the internal eventfd context, otherwise the error
	264	* pointers returned by the following functions:
	265	*
	266	* eventfd_fget
	267	*/
	268	struct eventfd_ctx *eventfd_ctx_fdget(int fd)
	269	{
	270	struct file *file;
	271	struct eventfd_ctx *ctx;
	272
	273	file = eventfd_fget(fd);
	274	if (IS_ERR(file))
	275	return (struct eventfd_ctx *) file;
	276	ctx = eventfd_ctx_get(file->private_data);
	277	fput(file);
	278
	279	return ctx;
	280	}
	281	EXPORT_SYMBOL_GPL(eventfd_ctx_fdget);
	282
	283	/**
	284	* eventfd_ctx_fileget - Acquires a reference to the internal eventfd context.
	285	* @file: [in] Eventfd file pointer.
	286	*
	287	* Returns a pointer to the internal eventfd context, otherwise the error
	288	* pointer:
	289	*
	290	* -EINVAL : The @fd file descriptor is not an eventfd file.
	291	*/
	292	struct eventfd_ctx eventfd_ctx_fileget(struct file file)
	293	{
	294	if (file->f_op != &eventfd_fops)
	295	return ERR_PTR(-EINVAL);
	296
	297	return eventfd_ctx_get(file->private_data);
	298	}
	299	EXPORT_SYMBOL_GPL(eventfd_ctx_fileget);
	300
d4e82042	301	SYSCALL_DEFINE2(eventfd2, unsigned int, count, int, flags)
e1ad7468	302	{
2030a42c	303	int fd;
e1ad7468	304	struct eventfd_ctx *ctx;
e1ad7468	305
e38b36f3 UD	306	/* Check the EFD_* constants for consistency. */
	307	BUILD_BUG_ON(EFD_CLOEXEC != O_CLOEXEC);
	308	BUILD_BUG_ON(EFD_NONBLOCK != O_NONBLOCK);
	309
bcd0b235	310	if (flags & ~EFD_FLAGS_SET)
b087498e UD	311	return -EINVAL;
b087498e UD	312
e1ad7468 DL	313	ctx = kmalloc(sizeof(*ctx), GFP_KERNEL);
	314	if (!ctx)
	315	return -ENOMEM;
	316
13389010	317	kref_init(&ctx->kref);
e1ad7468	318	init_waitqueue_head(&ctx->wqh);
e1ad7468	319	ctx->count = count;
bcd0b235	320	ctx->flags = flags;
e1ad7468 DL	321
	322	/*
	323	* When we call this, the initialization must be complete, since
	324	* anon_inode_getfd() will install the fd.
	325	*/
b087498e	326	fd = anon_inode_getfd("[eventfd]", &eventfd_fops, ctx,
bcd0b235	327	flags & EFD_SHARED_FCNTL_FLAGS);
2030a42c AV	328	if (fd < 0)
	329	kfree(ctx);
	330	return fd;
e1ad7468 DL	331	}
e1ad7468 DL	332
d4e82042	333	SYSCALL_DEFINE1(eventfd, unsigned int, count)
b087498e UD	334	{
	335	return sys_eventfd2(count, 0);
	336	}
bcd0b235	337