From 1366c37ed84b166a0fffe201154b0d3b78a3976b Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Thu, 17 Mar 2016 14:21:45 -0700 Subject: radix tree test harness This code is mostly from Andrew Morton and Nick Piggin; tarball downloaded from http://ozlabs.org/~akpm/rtth.tar.gz with sha1sum 0ce679db9ec047296b5d1ff7a1dfaa03a7bef1bd Some small modifications were necessary to the test harness to fix the build with the current Linux source code. I also made minor modifications to automatically test the radix-tree.c and radix-tree.h files that are in the current source tree, as opposed to a copied and slightly modified version. I am sure more could be done to tidy up the harness, as well as adding more tests. [koct9i@gmail.com: fix compilation] Signed-off-by: Matthew Wilcox Cc: Shuah Khan Cc: Johannes Weiner Cc: Matthew Wilcox Cc: "Kirill A. Shutemov" Cc: Ross Zwisler Cc: Hugh Dickins Signed-off-by: Konstantin Khlebnikov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- tools/testing/radix-tree/linux/bitops/__ffs.h | 43 +++++++++++++++++++++++++++ 1 file changed, 43 insertions(+) create mode 100644 tools/testing/radix-tree/linux/bitops/__ffs.h (limited to 'tools/testing/radix-tree/linux/bitops/__ffs.h') diff --git a/tools/testing/radix-tree/linux/bitops/__ffs.h b/tools/testing/radix-tree/linux/bitops/__ffs.h new file mode 100644 index 000000000000..9a3274aecf83 --- /dev/null +++ b/tools/testing/radix-tree/linux/bitops/__ffs.h @@ -0,0 +1,43 @@ +#ifndef _ASM_GENERIC_BITOPS___FFS_H_ +#define _ASM_GENERIC_BITOPS___FFS_H_ + +#include + +/** + * __ffs - find first bit in word. + * @word: The word to search + * + * Undefined if no bit exists, so code should check against 0 first. + */ +static inline unsigned long __ffs(unsigned long word) +{ + int num = 0; + +#if BITS_PER_LONG == 64 + if ((word & 0xffffffff) == 0) { + num += 32; + word >>= 32; + } +#endif + if ((word & 0xffff) == 0) { + num += 16; + word >>= 16; + } + if ((word & 0xff) == 0) { + num += 8; + word >>= 8; + } + if ((word & 0xf) == 0) { + num += 4; + word >>= 4; + } + if ((word & 0x3) == 0) { + num += 2; + word >>= 2; + } + if ((word & 0x1) == 0) + num += 1; + return num; +} + +#endif /* _ASM_GENERIC_BITOPS___FFS_H_ */ -- cgit v1.2.3