/*
* Copyright (c) 2001-2004 Jakub Jermar
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* - The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/** @addtogroup sync
* @{
*/
/** @file
*/
#ifndef KERN_WAITQ_H_
#define KERN_WAITQ_H_
#include <arch/types.h>
#include <synch/spinlock.h>
#include <synch/synch.h>
#include <adt/list.h>
/** Specifies behavior of the waitq_wakeup */
typedef enum {
WAKEUP_FIRST = 0, /**< Wakes up only the first sleeping thread, if there
aren't any sleeping threads increments missed wakeups */
WAKEUP_ALL = 1, /**< Wakes up all sleeping threads AND zeroes out
missed_wakeups */
WAKEUP_ALL_INC_MISSED, /**< Wakes up all sleeping threads OR increments
missed_wakeups if there aren't any */
} wakeup_all_flag_t;
/** Wait queue structure. */
typedef struct {
/** Lock protecting wait queue structure.
*
* Must be acquired before T.lock for each T of type thread_t.
*/
SPINLOCK_DECLARE(lock);
/**
* Number of waitq_wakeup() calls that didn't find a thread to wake up.
*/
int missed_wakeups;
/** List of sleeping threads for wich there was no missed_wakeup. */
link_t head;
} waitq_t;
#define waitq_sleep(wq) \
waitq_sleep_timeout((wq), SYNCH_NO_TIMEOUT, SYNCH_FLAGS_NONE)
struct thread;
extern void waitq_initialize(waitq_t *wq);
extern int waitq_sleep_timeout(waitq_t *wq, uint32_t usec, int flags);
extern ipl_t waitq_sleep_prepare(waitq_t *wq);
extern int waitq_sleep_timeout_unsafe(waitq_t *wq, uint32_t usec, int flags);
extern void waitq_sleep_finish(waitq_t *wq, int rc, ipl_t ipl);
extern void waitq_wakeup(waitq_t *wq, int all);
extern void _waitq_wakeup_unsafe(waitq_t *wq, int all);
extern void waitq_interrupt_sleep(struct thread *t);
#endif
/** @}
*/