Esempi in C++ (Cpp) per __init_sched_fifo_prio

Esempio n. 1

int
__pthread_tpp_change_priority (int previous_prio, int new_prio)
{
  struct pthread *self = THREAD_SELF;
  struct priority_protection_data *tpp = THREAD_GETMEM (self, tpp);

  if (tpp == NULL)
    {
      if (__sched_fifo_min_prio == -1)
	__init_sched_fifo_prio ();

      size_t size = sizeof *tpp;
      size += (__sched_fifo_max_prio - __sched_fifo_min_prio + 1)
	      * sizeof (tpp->priomap[0]);
      tpp = calloc (size, 1);
      if (tpp == NULL)
	return ENOMEM;
      tpp->priomax = __sched_fifo_min_prio - 1;
      THREAD_SETMEM (self, tpp, tpp);
    }

  assert (new_prio == -1
	  || (new_prio >= __sched_fifo_min_prio
	      && new_prio <= __sched_fifo_max_prio));
  assert (previous_prio == -1
	  || (previous_prio >= __sched_fifo_min_prio
	      && previous_prio <= __sched_fifo_max_prio));

  int priomax = tpp->priomax;
  int newpriomax = priomax;
  if (new_prio != -1)
    {
      if (tpp->priomap[new_prio - __sched_fifo_min_prio] + 1 == 0)
	return EAGAIN;
      ++tpp->priomap[new_prio - __sched_fifo_min_prio];
      if (new_prio > priomax)
	newpriomax = new_prio;
    }

  if (previous_prio != -1)
    {
      if (--tpp->priomap[previous_prio - __sched_fifo_min_prio] == 0
	  && priomax == previous_prio
	  && previous_prio > new_prio)
	{
	  int i;
	  for (i = previous_prio - 1; i >= __sched_fifo_min_prio; --i)
	    if (tpp->priomap[i - __sched_fifo_min_prio])
	      break;
	  newpriomax = i;
	}
    }

  if (priomax == newpriomax)
    return 0;

  lll_lock (self->lock, LLL_PRIVATE);

  tpp->priomax = newpriomax;

  int result = 0;
#ifdef TPP_PTHREAD_SCHED
  int policy;
  struct sched_param param;
#endif

  if ((self->flags & ATTR_FLAG_SCHED_SET) == 0)
    {
#ifndef TPP_PTHREAD_SCHED
      if (__sched_getparam (self->tid, &self->schedparam) != 0)
#else
      if (__pthread_getschedparam (self->tid, &policy, &self->schedparam) != 0)
#endif
	result = errno;
      else
	self->flags |= ATTR_FLAG_SCHED_SET;
    }

  if ((self->flags & ATTR_FLAG_POLICY_SET) == 0)
    {
#ifndef TPP_PTHREAD_SCHED
      self->schedpolicy = __sched_getscheduler (self->tid);
#else
      if (__pthread_getschedparam (self->tid, &self->schedpolicy, &param) != 0)
        self->schedpolicy = -1;
#endif
      if (self->schedpolicy == -1)
	result = errno;
      else
	self->flags |= ATTR_FLAG_POLICY_SET;
    }

  if (result == 0)
    {
      struct sched_param sp = self->schedparam;
      if (sp.sched_priority < newpriomax || sp.sched_priority < priomax)
	{
	  if (sp.sched_priority < newpriomax)
	    sp.sched_priority = newpriomax;

#ifndef TPP_PTHREAD_SCHED
	  if (__sched_setscheduler (self->tid, self->schedpolicy, &sp) < 0)
#else
      if (__pthread_setschedparam (self->tid, self->schedpolicy, &sp) < 0)
#endif
	    result = errno;
	}
    }

  lll_unlock (self->lock, LLL_PRIVATE);

  return result;
}

Esempio n. 2

File: tpp.c Progetto: siddhesh/glibc

int
__pthread_tpp_change_priority (int previous_prio, int new_prio)
{
  struct pthread *self = THREAD_SELF;
  struct priority_protection_data *tpp = THREAD_GETMEM (self, tpp);
  int fifo_min_prio = atomic_load_relaxed (&__sched_fifo_min_prio);
  int fifo_max_prio = atomic_load_relaxed (&__sched_fifo_max_prio);

  if (tpp == NULL)
    {
      /* See __init_sched_fifo_prio.  We need both the min and max prio,
         so need to check both, and run initialization if either one is
         not initialized.  The memory model's write-read coherence rule
         makes this work.  */
      if (fifo_min_prio == -1 || fifo_max_prio == -1)
	{
	  __init_sched_fifo_prio ();
	  fifo_min_prio = atomic_load_relaxed (&__sched_fifo_min_prio);
	  fifo_max_prio = atomic_load_relaxed (&__sched_fifo_max_prio);
	}

      size_t size = sizeof *tpp;
      size += (fifo_max_prio - fifo_min_prio + 1)
	      * sizeof (tpp->priomap[0]);
      tpp = calloc (size, 1);
      if (tpp == NULL)
	return ENOMEM;
      tpp->priomax = fifo_min_prio - 1;
      THREAD_SETMEM (self, tpp, tpp);
    }

  assert (new_prio == -1
	  || (new_prio >= fifo_min_prio
	      && new_prio <= fifo_max_prio));
  assert (previous_prio == -1
	  || (previous_prio >= fifo_min_prio
	      && previous_prio <= fifo_max_prio));

  int priomax = tpp->priomax;
  int newpriomax = priomax;
  if (new_prio != -1)
    {
      if (tpp->priomap[new_prio - fifo_min_prio] + 1 == 0)
	return EAGAIN;
      ++tpp->priomap[new_prio - fifo_min_prio];
      if (new_prio > priomax)
	newpriomax = new_prio;
    }

  if (previous_prio != -1)
    {
      if (--tpp->priomap[previous_prio - fifo_min_prio] == 0
	  && priomax == previous_prio
	  && previous_prio > new_prio)
	{
	  int i;
	  for (i = previous_prio - 1; i >= fifo_min_prio; --i)
	    if (tpp->priomap[i - fifo_min_prio])
	      break;
	  newpriomax = i;
	}
    }

  if (priomax == newpriomax)
    return 0;

  /* See CREATE THREAD NOTES in nptl/pthread_create.c.  */
  lll_lock (self->lock, LLL_PRIVATE);

  tpp->priomax = newpriomax;

  int result = 0;

  if ((self->flags & ATTR_FLAG_SCHED_SET) == 0)
    {
      if (__sched_getparam (self->tid, &self->schedparam) != 0)
	result = errno;
      else
	self->flags |= ATTR_FLAG_SCHED_SET;
    }

  if ((self->flags & ATTR_FLAG_POLICY_SET) == 0)
    {
      self->schedpolicy = __sched_getscheduler (self->tid);
      if (self->schedpolicy == -1)
	result = errno;
      else
	self->flags |= ATTR_FLAG_POLICY_SET;
    }

  if (result == 0)
    {
      struct sched_param sp = self->schedparam;
      if (sp.sched_priority < newpriomax || sp.sched_priority < priomax)
	{
	  if (sp.sched_priority < newpriomax)
	    sp.sched_priority = newpriomax;

	  if (__sched_setscheduler (self->tid, self->schedpolicy, &sp) < 0)
	    result = errno;
	}
    }

  lll_unlock (self->lock, LLL_PRIVATE);

  return result;
}