posix/src/pspinlock.c

0001 /* SPDX-License-Identifier: BSD-2-Clause */
0002
0003 /**
0004  *  @file
0005  *
0006  *  @brief Wait at a Spinlock
0007  *  @ingroup POSIXAPI
0008  */
0009
0010 /*
0011  *  COPYRIGHT (c) 1989-2007.
0012  *  On-Line Applications Research Corporation (OAR).
0013  *
0014  *  Copyright (c) 2016 embedded brains GmbH & Co. KG
0015  *
0016  * Redistribution and use in source and binary forms, with or without
0017  * modification, are permitted provided that the following conditions
0018  * are met:
0019  * 1. Redistributions of source code must retain the above copyright
0020  *    notice, this list of conditions and the following disclaimer.
0021  * 2. Redistributions in binary form must reproduce the above copyright
0022  *    notice, this list of conditions and the following disclaimer in the
0023  *    documentation and/or other materials provided with the distribution.
0024  *
0025  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
0026  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
0027  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
0028  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
0029  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
0030  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
0031  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
0032  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
0033  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
0034  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
0035  * POSSIBILITY OF SUCH DAMAGE.
0036  */
0037
0038 #ifdef HAVE_CONFIG_H
0039 #include "config.h"
0040 #endif
0041
0042 #include <rtems/posix/spinlockimpl.h>
0043
0044 RTEMS_STATIC_ASSERT(
0045 #if defined(RTEMS_SMP)
0046   offsetof( POSIX_Spinlock_Control, Lock.next_ticket )
0047 #else
0048   offsetof( POSIX_Spinlock_Control, reserved[ 0 ] )
0049 #endif
0050     == offsetof( pthread_spinlock_t, _Lock._next_ticket ),
0051   POSIX_SPINLOCK_T_LOCK_NEXT_TICKET
0052 );
0053
0054 RTEMS_STATIC_ASSERT(
0055 #if defined(RTEMS_SMP)
0056   offsetof( POSIX_Spinlock_Control, Lock.now_serving )
0057 #else
0058   offsetof( POSIX_Spinlock_Control, reserved[ 1 ] )
0059 #endif
0060     == offsetof( pthread_spinlock_t, _Lock._now_serving ),
0061   POSIX_SPINLOCK_T_LOCK_NOW_SERVING
0062 );
0063
0064 RTEMS_STATIC_ASSERT(
0065   offsetof( POSIX_Spinlock_Control, interrupt_state )
0066     == offsetof( pthread_spinlock_t, _interrupt_state ),
0067   POSIX_SPINLOCK_T_INTERRUPT_STATE
0068 );
0069
0070 RTEMS_STATIC_ASSERT(
0071   sizeof( POSIX_Spinlock_Control ) == sizeof( pthread_spinlock_t ),
0072   POSIX_SPINLOCK_T_SIZE
0073 );
0074
0075 int pthread_spin_lock( pthread_spinlock_t *spinlock )
0076 {
0077   POSIX_Spinlock_Control *the_spinlock;
0078   ISR_Level               level;
0079 #if defined(RTEMS_SMP) && defined(RTEMS_PROFILING)
0080   SMP_lock_Stats          unused_stats;
0081   SMP_lock_Stats_context  unused_context;
0082 #endif
0083
0084   the_spinlock = _POSIX_Spinlock_Get( spinlock );
0085   _ISR_Local_disable( level );
0086 #if defined(RTEMS_SMP)
0087   _SMP_ticket_lock_Acquire(
0088     &the_spinlock->Lock,
0089     &unused_stats,
0090     &unused_context
0091   );
0092 #endif
0093   the_spinlock->interrupt_state = level;
0094   return 0;
0095 }
0096
0097 int pthread_spin_trylock( pthread_spinlock_t *spinlock )
0098   RTEMS_ALIAS( pthread_spin_lock );