rockbox/firmware/kernel/include/corelock.h
Thomas Martitz 382d1861af kernel: Break out kernel primitives into separate files and move to separate dir.
No code changed, just shuffling stuff around. This should make it easier to
build only select parts kernel and use different implementations.

Change-Id: Ie1f00f93008833ce38419d760afd70062c5e22b5
2014-03-03 18:11:57 +01:00

53 lines
1.7 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2002 by Ulf Ralberg
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#ifndef CORELOCK_H
#define CORELOCK_H
#include "config.h"
#ifndef HAVE_CORELOCK_OBJECT
/* No atomic corelock op needed or just none defined */
#define corelock_init(cl)
#define corelock_lock(cl)
#define corelock_try_lock(cl)
#define corelock_unlock(cl)
#else
/* No reliable atomic instruction available - use Peterson's algorithm */
struct corelock
{
volatile unsigned char myl[NUM_CORES];
volatile unsigned char turn;
} __attribute__((packed));
/* Too big to inline everywhere */
extern void corelock_init(struct corelock *cl);
extern void corelock_lock(struct corelock *cl);
extern int corelock_try_lock(struct corelock *cl);
extern void corelock_unlock(struct corelock *cl);
#endif /* HAVE_CORELOCK_OBJECT */
#endif /* CORELOCK_H */