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-rw-r--r--firmware/kernel/include/corelock.h53
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diff --git a/firmware/kernel/include/corelock.h b/firmware/kernel/include/corelock.h
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+/***************************************************************************
+ * __________ __ ___.
+ * 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 */