Subversion Repositories openrisc_2011-10-31

/* Linuxthreads - a simple clone()-based implementation of Posix        */

/* threads for Linux.                                                   */

/* Copyright (C) 1996 Xavier Leroy (Xavier.Leroy@inria.fr)              */

/*                                                                      */

/* This program is free software; you can redistribute it and/or        */

/* modify it under the terms of the GNU Library General Public License  */

/* as published by the Free Software Foundation; either version 2       */

/* of the License, or (at your option) any later version.               */

/*                                                                      */

/* This program is distributed in the hope that it will be useful,      */

/* but WITHOUT ANY WARRANTY; without even the implied warranty of       */

/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the        */

/* GNU Library General Public License for more details.                 */

/* Waiting queues */

/* Waiting queues are represented by lists of thread descriptors

   linked through their p_nextwaiting field.  The lists are kept

   sorted by decreasing priority, and then decreasing waiting time. */

static inline void enqueue(pthread_descr * q, pthread_descr th)

{

  int prio = th->p_priority;

  ASSERT(th->p_nextwaiting == NULL);

  for (; *q != NULL; q = &((*q)->p_nextwaiting)) {

    if (prio > (*q)->p_priority) {

      th->p_nextwaiting = *q;

      *q = th;

      return;

    }

  }

  *q = th;

}

static inline pthread_descr dequeue(pthread_descr * q)

{

  pthread_descr th;

  th = *q;

  if (th != NULL) {

    *q = th->p_nextwaiting;

    th->p_nextwaiting = NULL;

  }

  return th;

}

static inline int remove_from_queue(pthread_descr * q, pthread_descr th)

{

  for (; *q != NULL; q = &((*q)->p_nextwaiting)) {

    if (*q == th) {

      *q = th->p_nextwaiting;

      th->p_nextwaiting = NULL;

      return 1;

    }

  }

  return 0;

}

static inline int queue_is_empty(pthread_descr * q)

{

    return *q == NULL;

}