diff options
Diffstat (limited to 'tools/include/linux')
-rw-r--r-- | tools/include/linux/log2.h | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/tools/include/linux/log2.h b/tools/include/linux/log2.h new file mode 100644 index 000000000000..141b7665d842 --- /dev/null +++ b/tools/include/linux/log2.h @@ -0,0 +1,26 @@ +/* Integer base 2 logarithm calculation + * + * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * 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. + */ + +#ifndef _TOOLS_LINUX_LOG2_H +#define _TOOLS_LINUX_LOG2_H + +/* + * Determine whether some value is a power of two, where zero is + * *not* considered a power of two. + */ + +static inline __attribute__((const)) +bool is_power_of_2(unsigned long n) +{ + return (n != 0 && ((n & (n - 1)) == 0)); +} + +#endif /* _TOOLS_LINUX_LOG2_H */ |