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-rw-r--r--arch/arc/include/asm/mutex.h18
1 files changed, 18 insertions, 0 deletions
diff --git a/arch/arc/include/asm/mutex.h b/arch/arc/include/asm/mutex.h
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+++ b/arch/arc/include/asm/mutex.h
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+/*
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+/*
+ * xchg() based mutex fast path maintains a state of 0 or 1, as opposed to
+ * atomic dec based which can "count" any number of lock contenders.
+ * This ideally needs to be fixed in core, but for now switching to dec ver.
+ */
+#if defined(CONFIG_SMP) && (CONFIG_NR_CPUS > 2)
+#include <asm-generic/mutex-dec.h>
+#else
+#include <asm-generic/mutex-xchg.h>
+#endif