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#ifndef _LINUX_WAIT_H
#define _LINUX_WAIT_H
#define WNOHANG 0x00000001
#define WUNTRACED 0x00000002
#define __WNOTHREAD 0x20000000 /* Don't wait on children of other threads in this group */
#define __WALL 0x40000000 /* Wait on all children, regardless of type */
#define __WCLONE 0x80000000 /* Wait only on non-SIGCHLD children */
#ifdef __KERNEL__
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/stddef.h>
#include <linux/spinlock.h>
#include <linux/config.h>
#include <asm/page.h>
#include <asm/processor.h>
/*
* Debug control. Slow but useful.
*/
#if defined(CONFIG_DEBUG_WAITQ)
#define WAITQUEUE_DEBUG 1
#else
#define WAITQUEUE_DEBUG 0
#endif
struct __wait_queue {
unsigned int flags;
#define WQ_FLAG_EXCLUSIVE 0x01
struct task_struct * task;
struct list_head task_list;
#if WAITQUEUE_DEBUG
long __magic;
long __waker;
#endif
};
typedef struct __wait_queue wait_queue_t;
/*
* 'dual' spinlock architecture. Can be switched between spinlock_t and
* rwlock_t locks via changing this define. Since waitqueues are quite
* decoupled in the new architecture, lightweight 'simple' spinlocks give
* us slightly better latencies and smaller waitqueue structure size.
*/
#define USE_RW_WAIT_QUEUE_SPINLOCK 0
#if USE_RW_WAIT_QUEUE_SPINLOCK
# define wq_lock_t rwlock_t
# define WAITQUEUE_RW_LOCK_UNLOCKED RW_LOCK_UNLOCKED
# define wq_read_lock read_lock
# define wq_read_lock_irqsave read_lock_irqsave
# define wq_read_unlock_irqrestore read_unlock_irqrestore
# define wq_read_unlock read_unlock
# define wq_write_lock_irq write_lock_irq
# define wq_write_lock_irqsave write_lock_irqsave
# define wq_write_unlock_irqrestore write_unlock_irqrestore
# define wq_write_unlock write_unlock
#else
# define wq_lock_t spinlock_t
# define WAITQUEUE_RW_LOCK_UNLOCKED SPIN_LOCK_UNLOCKED
# define wq_read_lock spin_lock
# define wq_read_lock_irqsave spin_lock_irqsave
# define wq_read_unlock spin_unlock
# define wq_read_unlock_irqrestore spin_unlock_irqrestore
# define wq_write_lock_irq spin_lock_irq
# define wq_write_lock_irqsave spin_lock_irqsave
# define wq_write_unlock_irqrestore spin_unlock_irqrestore
# define wq_write_unlock spin_unlock
#endif
struct __wait_queue_head {
wq_lock_t lock;
struct list_head task_list;
#if WAITQUEUE_DEBUG
long __magic;
long __creator;
#endif
};
typedef struct __wait_queue_head wait_queue_head_t;
/*
* Debugging macros. We eschew `do { } while (0)' because gcc can generate
* spurious .aligns.
*/
#if WAITQUEUE_DEBUG
#define WQ_BUG() BUG()
#define CHECK_MAGIC(x) \
do { \
if ((x) != (long)&(x)) { \
printk("bad magic %lx (should be %lx), ", \
(long)x, (long)&(x)); \
WQ_BUG(); \
} \
} while (0)
#define CHECK_MAGIC_WQHEAD(x) \
do { \
if ((x)->__magic != (long)&((x)->__magic)) { \
printk("bad magic %lx (should be %lx, creator %lx), ", \
(x)->__magic, (long)&((x)->__magic), (x)->__creator); \
WQ_BUG(); \
} \
} while (0)
#define WQ_CHECK_LIST_HEAD(list) \
do { \
if (!(list)->next || !(list)->prev) \
WQ_BUG(); \
} while(0)
#define WQ_NOTE_WAKER(tsk) \
do { \
(tsk)->__waker = (long)__builtin_return_address(0); \
} while (0)
#else
#define WQ_BUG()
#define CHECK_MAGIC(x)
#define CHECK_MAGIC_WQHEAD(x)
#define WQ_CHECK_LIST_HEAD(list)
#define WQ_NOTE_WAKER(tsk)
#endif
/*
* Macros for declaration and initialisaton of the datatypes
*/
#if WAITQUEUE_DEBUG
# define __WAITQUEUE_DEBUG_INIT(name) (long)&(name).__magic, 0
# define __WAITQUEUE_HEAD_DEBUG_INIT(name) (long)&(name).__magic, (long)&(name).__magic
#else
# define __WAITQUEUE_DEBUG_INIT(name)
# define __WAITQUEUE_HEAD_DEBUG_INIT(name)
#endif
#define __WAITQUEUE_INITIALIZER(name, tsk) { \
task: tsk, \
task_list: { NULL, NULL }, \
__WAITQUEUE_DEBUG_INIT(name)}
#define DECLARE_WAITQUEUE(name, tsk) \
wait_queue_t name = __WAITQUEUE_INITIALIZER(name, tsk)
#define __WAIT_QUEUE_HEAD_INITIALIZER(name) { \
lock: WAITQUEUE_RW_LOCK_UNLOCKED, \
task_list: { &(name).task_list, &(name).task_list }, \
__WAITQUEUE_HEAD_DEBUG_INIT(name)}
#define DECLARE_WAIT_QUEUE_HEAD(name) \
wait_queue_head_t name = __WAIT_QUEUE_HEAD_INITIALIZER(name)
static inline void init_waitqueue_head(wait_queue_head_t *q)
{
#if WAITQUEUE_DEBUG
if (!q)
WQ_BUG();
#endif
q->lock = WAITQUEUE_RW_LOCK_UNLOCKED;
INIT_LIST_HEAD(&q->task_list);
#if WAITQUEUE_DEBUG
q->__magic = (long)&q->__magic;
q->__creator = (long)current_text_addr();
#endif
}
static inline void init_waitqueue_entry(wait_queue_t *q, struct task_struct *p)
{
#if WAITQUEUE_DEBUG
if (!q || !p)
WQ_BUG();
#endif
q->flags = 0;
q->task = p;
#if WAITQUEUE_DEBUG
q->__magic = (long)&q->__magic;
#endif
}
static inline int waitqueue_active(wait_queue_head_t *q)
{
#if WAITQUEUE_DEBUG
if (!q)
WQ_BUG();
CHECK_MAGIC_WQHEAD(q);
#endif
return !list_empty(&q->task_list);
}
static inline void __add_wait_queue(wait_queue_head_t *head, wait_queue_t *new)
{
#if WAITQUEUE_DEBUG
if (!head || !new)
WQ_BUG();
CHECK_MAGIC_WQHEAD(head);
CHECK_MAGIC(new->__magic);
if (!head->task_list.next || !head->task_list.prev)
WQ_BUG();
#endif
list_add(&new->task_list, &head->task_list);
}
/*
* Used for wake-one threads:
*/
static inline void __add_wait_queue_tail(wait_queue_head_t *head,
wait_queue_t *new)
{
#if WAITQUEUE_DEBUG
if (!head || !new)
WQ_BUG();
CHECK_MAGIC_WQHEAD(head);
CHECK_MAGIC(new->__magic);
if (!head->task_list.next || !head->task_list.prev)
WQ_BUG();
#endif
list_add_tail(&new->task_list, &head->task_list);
}
static inline void __remove_wait_queue(wait_queue_head_t *head,
wait_queue_t *old)
{
#if WAITQUEUE_DEBUG
if (!old)
WQ_BUG();
CHECK_MAGIC(old->__magic);
#endif
list_del(&old->task_list);
}
#endif /* __KERNEL__ */
#endif
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