diff options
author | Matthew Wilcox <willy@linux.intel.com> | 2016-03-17 14:21:45 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-03-17 15:09:34 -0700 |
commit | 1366c37ed84b166a0fffe201154b0d3b78a3976b (patch) | |
tree | 3a688edaf09069694db90421f200568b886a4295 /tools/testing/radix-tree/linux/bitops/fls.h | |
parent | f67c07f07fca95a7f330b8bb928eabaf9fcce75d (diff) |
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 <willy@linux.intel.com>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'tools/testing/radix-tree/linux/bitops/fls.h')
-rw-r--r-- | tools/testing/radix-tree/linux/bitops/fls.h | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/tools/testing/radix-tree/linux/bitops/fls.h b/tools/testing/radix-tree/linux/bitops/fls.h new file mode 100644 index 000000000000..850859bc5069 --- /dev/null +++ b/tools/testing/radix-tree/linux/bitops/fls.h @@ -0,0 +1,41 @@ +#ifndef _ASM_GENERIC_BITOPS_FLS_H_ +#define _ASM_GENERIC_BITOPS_FLS_H_ + +/** + * fls - find last (most-significant) bit set + * @x: the word to search + * + * This is defined the same way as ffs. + * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32. + */ + +static inline int fls(int x) +{ + int r = 32; + + if (!x) + return 0; + if (!(x & 0xffff0000u)) { + x <<= 16; + r -= 16; + } + if (!(x & 0xff000000u)) { + x <<= 8; + r -= 8; + } + if (!(x & 0xf0000000u)) { + x <<= 4; + r -= 4; + } + if (!(x & 0xc0000000u)) { + x <<= 2; + r -= 2; + } + if (!(x & 0x80000000u)) { + x <<= 1; + r -= 1; + } + return r; +} + +#endif /* _ASM_GENERIC_BITOPS_FLS_H_ */ |