freebsd-dev/lib/libc_r/uthread/uthread_priority_queue.c
Daniel Eischen 5eb8d1f0b0 Revamp suspend and resume. While I'm here add pthread_suspend_all_np()
and pthread_resume_all_np().  These suspend and resume all threads except
the current thread, respectively.  The existing functions pthread_single_np()
and pthread_multi_np(), which formerly had no effect, now exhibit the same
behaviour and pthread_suspend_all_np() and pthread_resume_all_np().  These
functions have been added mostly for the native java port.

Don't allow the uthread kernel pipe to use the same descriptors as
stdio.  Mostily submitted by Oswald Buddenhagen <ossi@kde.org>.

Correct some minor style nits.
2002-05-24 04:32:28 +00:00

371 lines
10 KiB
C

/*
* Copyright (c) 1998 Daniel Eischen <eischen@vigrid.com>.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Daniel Eischen.
* 4. Neither the name of the author nor the names of any co-contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY DANIEL EISCHEN AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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.
*
* $FreeBSD$
*/
#include <stdlib.h>
#include <sys/queue.h>
#include <string.h>
#include <pthread.h>
#include "pthread_private.h"
/* Prototypes: */
static void pq_insert_prio_list(pq_queue_t *pq, int prio);
#if defined(_PTHREADS_INVARIANTS)
static int _pq_active = 0;
#define _PQ_IN_SCHEDQ (PTHREAD_FLAGS_IN_PRIOQ | PTHREAD_FLAGS_IN_WAITQ | PTHREAD_FLAGS_IN_WORKQ)
#define _PQ_SET_ACTIVE() _pq_active = 1
#define _PQ_CLEAR_ACTIVE() _pq_active = 0
#define _PQ_ASSERT_ACTIVE(msg) do { \
if (_pq_active == 0) \
PANIC(msg); \
} while (0)
#define _PQ_ASSERT_INACTIVE(msg) do { \
if (_pq_active != 0) \
PANIC(msg); \
} while (0)
#define _PQ_ASSERT_IN_WAITQ(thrd, msg) do { \
if (((thrd)->flags & PTHREAD_FLAGS_IN_WAITQ) == 0) \
PANIC(msg); \
} while (0)
#define _PQ_ASSERT_IN_PRIOQ(thrd, msg) do { \
if (((thrd)->flags & PTHREAD_FLAGS_IN_PRIOQ) == 0) \
PANIC(msg); \
} while (0)
#define _PQ_ASSERT_NOT_QUEUED(thrd, msg) do { \
if (((thrd)->flags & _PQ_IN_SCHEDQ) != 0) \
PANIC(msg); \
} while (0)
#define _PQ_ASSERT_PROTECTED(msg) \
PTHREAD_ASSERT((_thread_kern_in_sched != 0) || \
((_get_curthread())->sig_defer_count > 0) ||\
(_sig_in_handler != 0), msg);
#else
#define _PQ_SET_ACTIVE()
#define _PQ_CLEAR_ACTIVE()
#define _PQ_ASSERT_ACTIVE(msg)
#define _PQ_ASSERT_INACTIVE(msg)
#define _PQ_ASSERT_IN_WAITQ(thrd, msg)
#define _PQ_ASSERT_IN_PRIOQ(thrd, msg)
#define _PQ_ASSERT_NOT_QUEUED(thrd, msg)
#define _PQ_ASSERT_PROTECTED(msg)
#endif
int
_pq_alloc(pq_queue_t *pq, int minprio, int maxprio)
{
int ret = 0;
int prioslots = maxprio - minprio + 1;
if (pq == NULL)
ret = -1;
/* Create the priority queue with (maxprio - minprio + 1) slots: */
else if ((pq->pq_lists =
(pq_list_t *) malloc(sizeof(pq_list_t) * prioslots)) == NULL)
ret = -1;
else {
/* Remember the queue size: */
pq->pq_size = prioslots;
ret = _pq_init(pq);
}
return (ret);
}
int
_pq_init(pq_queue_t *pq)
{
int i, ret = 0;
if ((pq == NULL) || (pq->pq_lists == NULL))
ret = -1;
else {
/* Initialize the queue for each priority slot: */
for (i = 0; i < pq->pq_size; i++) {
TAILQ_INIT(&pq->pq_lists[i].pl_head);
pq->pq_lists[i].pl_prio = i;
pq->pq_lists[i].pl_queued = 0;
}
/* Initialize the priority queue: */
TAILQ_INIT(&pq->pq_queue);
_PQ_CLEAR_ACTIVE();
}
return (ret);
}
void
_pq_remove(pq_queue_t *pq, pthread_t pthread)
{
int prio = pthread->active_priority;
/*
* Make some assertions when debugging is enabled:
*/
_PQ_ASSERT_INACTIVE("_pq_remove: pq_active");
_PQ_SET_ACTIVE();
_PQ_ASSERT_IN_PRIOQ(pthread, "_pq_remove: Not in priority queue");
_PQ_ASSERT_PROTECTED("_pq_remove: prioq not protected!");
/*
* Remove this thread from priority list. Note that if
* the priority list becomes empty, it is not removed
* from the priority queue because another thread may be
* added to the priority list (resulting in a needless
* removal/insertion). Priority lists are only removed
* from the priority queue when _pq_first is called.
*/
TAILQ_REMOVE(&pq->pq_lists[prio].pl_head, pthread, pqe);
/* This thread is now longer in the priority queue. */
pthread->flags &= ~PTHREAD_FLAGS_IN_PRIOQ;
_PQ_CLEAR_ACTIVE();
}
void
_pq_insert_head(pq_queue_t *pq, pthread_t pthread)
{
int prio;
/*
* Don't insert suspended threads into the priority queue.
* The caller is responsible for setting the threads state.
*/
if ((pthread->flags & PTHREAD_FLAGS_SUSPENDED) != 0) {
/* Make sure the threads state is suspended. */
if (pthread->state != PS_SUSPENDED)
PTHREAD_SET_STATE(pthread, PS_SUSPENDED);
} else {
/*
* Make some assertions when debugging is enabled:
*/
_PQ_ASSERT_INACTIVE("_pq_insert_head: pq_active");
_PQ_SET_ACTIVE();
_PQ_ASSERT_NOT_QUEUED(pthread,
"_pq_insert_head: Already in priority queue");
_PQ_ASSERT_PROTECTED("_pq_insert_head: prioq not protected!");
prio = pthread->active_priority;
TAILQ_INSERT_HEAD(&pq->pq_lists[prio].pl_head, pthread, pqe);
if (pq->pq_lists[prio].pl_queued == 0)
/* Insert the list into the priority queue: */
pq_insert_prio_list(pq, prio);
/* Mark this thread as being in the priority queue. */
pthread->flags |= PTHREAD_FLAGS_IN_PRIOQ;
_PQ_CLEAR_ACTIVE();
}
}
void
_pq_insert_tail(pq_queue_t *pq, pthread_t pthread)
{
int prio;
/*
* Don't insert suspended threads into the priority queue.
* The caller is responsible for setting the threads state.
*/
if ((pthread->flags & PTHREAD_FLAGS_SUSPENDED) != 0) {
/* Make sure the threads state is suspended. */
if (pthread->state != PS_SUSPENDED)
PTHREAD_SET_STATE(pthread, PS_SUSPENDED);
} else {
/*
* Make some assertions when debugging is enabled:
*/
_PQ_ASSERT_INACTIVE("_pq_insert_tail: pq_active");
_PQ_SET_ACTIVE();
_PQ_ASSERT_NOT_QUEUED(pthread,
"_pq_insert_tail: Already in priority queue");
_PQ_ASSERT_PROTECTED("_pq_insert_tail: prioq not protected!");
prio = pthread->active_priority;
TAILQ_INSERT_TAIL(&pq->pq_lists[prio].pl_head, pthread, pqe);
if (pq->pq_lists[prio].pl_queued == 0)
/* Insert the list into the priority queue: */
pq_insert_prio_list(pq, prio);
/* Mark this thread as being in the priority queue. */
pthread->flags |= PTHREAD_FLAGS_IN_PRIOQ;
_PQ_CLEAR_ACTIVE();
}
}
pthread_t
_pq_first(pq_queue_t *pq)
{
pq_list_t *pql;
pthread_t pthread = NULL;
/*
* Make some assertions when debugging is enabled:
*/
_PQ_ASSERT_INACTIVE("_pq_first: pq_active");
_PQ_SET_ACTIVE();
_PQ_ASSERT_PROTECTED("_pq_first: prioq not protected!");
while (((pql = TAILQ_FIRST(&pq->pq_queue)) != NULL) &&
(pthread == NULL)) {
if ((pthread = TAILQ_FIRST(&pql->pl_head)) == NULL) {
/*
* The priority list is empty; remove the list
* from the queue.
*/
TAILQ_REMOVE(&pq->pq_queue, pql, pl_link);
/* Mark the list as not being in the queue: */
pql->pl_queued = 0;
} else if ((pthread->flags & PTHREAD_FLAGS_SUSPENDED) != 0) {
/*
* This thread is suspended; remove it from the
* list and ensure its state is suspended.
*/
TAILQ_REMOVE(&pql->pl_head, pthread, pqe);
PTHREAD_SET_STATE(pthread, PS_SUSPENDED);
/* This thread is now longer in the priority queue. */
pthread->flags &= ~PTHREAD_FLAGS_IN_PRIOQ;
pthread = NULL;
}
}
_PQ_CLEAR_ACTIVE();
return (pthread);
}
static void
pq_insert_prio_list(pq_queue_t *pq, int prio)
{
pq_list_t *pql;
/*
* Make some assertions when debugging is enabled:
*/
_PQ_ASSERT_ACTIVE("pq_insert_prio_list: pq_active");
_PQ_ASSERT_PROTECTED("_pq_insert_prio_list: prioq not protected!");
/*
* The priority queue is in descending priority order. Start at
* the beginning of the queue and find the list before which the
* new list should be inserted.
*/
pql = TAILQ_FIRST(&pq->pq_queue);
while ((pql != NULL) && (pql->pl_prio > prio))
pql = TAILQ_NEXT(pql, pl_link);
/* Insert the list: */
if (pql == NULL)
TAILQ_INSERT_TAIL(&pq->pq_queue, &pq->pq_lists[prio], pl_link);
else
TAILQ_INSERT_BEFORE(pql, &pq->pq_lists[prio], pl_link);
/* Mark this list as being in the queue: */
pq->pq_lists[prio].pl_queued = 1;
}
void
_waitq_insert(pthread_t pthread)
{
pthread_t tid;
/*
* Make some assertions when debugging is enabled:
*/
_PQ_ASSERT_INACTIVE("_waitq_insert: pq_active");
_PQ_SET_ACTIVE();
_PQ_ASSERT_NOT_QUEUED(pthread, "_waitq_insert: Already in queue");
if (pthread->wakeup_time.tv_sec == -1)
TAILQ_INSERT_TAIL(&_waitingq, pthread, pqe);
else {
tid = TAILQ_FIRST(&_waitingq);
while ((tid != NULL) && (tid->wakeup_time.tv_sec != -1) &&
((tid->wakeup_time.tv_sec < pthread->wakeup_time.tv_sec) ||
((tid->wakeup_time.tv_sec == pthread->wakeup_time.tv_sec) &&
(tid->wakeup_time.tv_nsec <= pthread->wakeup_time.tv_nsec))))
tid = TAILQ_NEXT(tid, pqe);
if (tid == NULL)
TAILQ_INSERT_TAIL(&_waitingq, pthread, pqe);
else
TAILQ_INSERT_BEFORE(tid, pthread, pqe);
}
pthread->flags |= PTHREAD_FLAGS_IN_WAITQ;
_PQ_CLEAR_ACTIVE();
}
void
_waitq_remove(pthread_t pthread)
{
/*
* Make some assertions when debugging is enabled:
*/
_PQ_ASSERT_INACTIVE("_waitq_remove: pq_active");
_PQ_SET_ACTIVE();
_PQ_ASSERT_IN_WAITQ(pthread, "_waitq_remove: Not in queue");
TAILQ_REMOVE(&_waitingq, pthread, pqe);
pthread->flags &= ~PTHREAD_FLAGS_IN_WAITQ;
_PQ_CLEAR_ACTIVE();
}
void
_waitq_setactive(void)
{
_PQ_ASSERT_INACTIVE("_waitq_setactive: pq_active");
_PQ_SET_ACTIVE();
}
void
_waitq_clearactive(void)
{
_PQ_ASSERT_ACTIVE("_waitq_clearactive: ! pq_active");
_PQ_CLEAR_ACTIVE();
}