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/**
 *  @file
 *
 *  @brief Wait at a Spinlock
 *  @ingroup POSIXAPI
 */

/*
 *  COPYRIGHT (c) 1989-2007.
 *  On-Line Applications Research Corporation (OAR).
 *
 *  Copyright (c) 2016 embedded brains GmbH
 *
 *  The license and distribution terms for this file may be
 *  found in the file LICENSE in this distribution or at
 *  http://www.rtems.org/license/LICENSE.
 */

#if HAVE_CONFIG_H
#include "config.h"
#endif

#include <rtems/posix/spinlockimpl.h>

#if defined(POSIX_SPINLOCKS_ARE_SELF_CONTAINED)
RTEMS_STATIC_ASSERT(
#if defined(RTEMS_SMP)
  offsetof( POSIX_Spinlock_Control, Lock.next_ticket )
#else
  offsetof( POSIX_Spinlock_Control, reserved[ 0 ] )
#endif
    == offsetof( pthread_spinlock_t, _Lock._next_ticket ),
  POSIX_SPINLOCK_T_LOCK_NEXT_TICKET
);

RTEMS_STATIC_ASSERT(
#if defined(RTEMS_SMP)
  offsetof( POSIX_Spinlock_Control, Lock.now_serving )
#else
  offsetof( POSIX_Spinlock_Control, reserved[ 1 ] )
#endif
    == offsetof( pthread_spinlock_t, _Lock._now_serving ),
  POSIX_SPINLOCK_T_LOCK_NOW_SERVING
);

RTEMS_STATIC_ASSERT(
  offsetof( POSIX_Spinlock_Control, interrupt_state )
    == offsetof( pthread_spinlock_t, _interrupt_state ),
  POSIX_SPINLOCK_T_INTERRUPT_STATE
);

RTEMS_STATIC_ASSERT(
  sizeof( POSIX_Spinlock_Control ) == sizeof( pthread_spinlock_t ),
  POSIX_SPINLOCK_T_SIZE
);
#else
#if defined(RTEMS_SMP)
POSIX_Spinlock_Control _POSIX_Spinlock_Global;

uint32_t _POSIX_Spinlock_Owner = 0xffffffff;
#endif

int _POSIX_Spinlock_Nest_level;
#endif

int pthread_spin_lock( pthread_spinlock_t *spinlock )
{
  POSIX_Spinlock_Control *the_spinlock;
  ISR_Level               level;
#if defined(RTEMS_SMP) && defined(RTEMS_PROFILING)
  Per_CPU_Control        *cpu_self;
#endif

  the_spinlock = _POSIX_Spinlock_Get( spinlock );
  _ISR_Local_disable( level );
#if defined(POSIX_SPINLOCKS_ARE_SELF_CONTAINED)
#if defined(RTEMS_SMP)
#if defined(RTEMS_PROFILING)
  /* The lock statistics are incorrect in case of nested pthread spinlocks */
  cpu_self = _Per_CPU_Get();
#endif
  _SMP_ticket_lock_Acquire(
    &the_spinlock->Lock,
    &cpu_self->Lock_stats,
    &cpu_self->Lock_stats_context
  );
#endif
  the_spinlock->interrupt_state = level;
#else
#if defined(RTEMS_SMP)
  if ( _POSIX_Spinlock_Owner != _SMP_Get_current_processor() ) {
#if defined(RTEMS_PROFILING)
    cpu_self = _Per_CPU_Get();
#endif
    _SMP_ticket_lock_Acquire(
      &the_spinlock->Lock,
      &cpu_self->Lock_stats,
      &cpu_self->Lock_stats_context
    );
    _POSIX_Spinlock_Owner = _SMP_Get_current_processor();
  }
#endif

  if ( ++_POSIX_Spinlock_Nest_level == 1) {
    the_spinlock->interrupt_state = level;
  }
#endif
  return 0;
}

int pthread_spin_trylock( pthread_spinlock_t *spinlock )
  RTEMS_ALIAS( pthread_spin_lock );