From fb72014d98afd51e85aab9c061344ef32d615606 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Fri, 30 Apr 2010 19:31:12 -0300 Subject: perf tools: Don't use code surrounded by __KERNEL__ MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit We need to refactor code to be explicitely shared by the kernel and at least the tools/ userspace programs, so, till we do that, copy the bare minimum bitmap/bitops code needed by tools/perf. Reported-by: "H. Peter Anvin" Cc: Frédéric Weisbecker Cc: Mike Galbraith Cc: Paul Mackerras Cc: Peter Zijlstra LKML-Reference: Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/hweight.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) create mode 100644 tools/perf/util/hweight.c (limited to 'tools/perf/util/hweight.c') diff --git a/tools/perf/util/hweight.c b/tools/perf/util/hweight.c new file mode 100644 index 000000000000..5c1d0d099f0d --- /dev/null +++ b/tools/perf/util/hweight.c @@ -0,0 +1,31 @@ +#include + +/** + * hweightN - returns the hamming weight of a N-bit word + * @x: the word to weigh + * + * The Hamming Weight of a number is the total number of bits set in it. + */ + +unsigned int hweight32(unsigned int w) +{ + unsigned int res = w - ((w >> 1) & 0x55555555); + res = (res & 0x33333333) + ((res >> 2) & 0x33333333); + res = (res + (res >> 4)) & 0x0F0F0F0F; + res = res + (res >> 8); + return (res + (res >> 16)) & 0x000000FF; +} + +unsigned long hweight64(__u64 w) +{ +#if BITS_PER_LONG == 32 + return hweight32((unsigned int)(w >> 32)) + hweight32((unsigned int)w); +#elif BITS_PER_LONG == 64 + __u64 res = w - ((w >> 1) & 0x5555555555555555ul); + res = (res & 0x3333333333333333ul) + ((res >> 2) & 0x3333333333333333ul); + res = (res + (res >> 4)) & 0x0F0F0F0F0F0F0F0Ful; + res = res + (res >> 8); + res = res + (res >> 16); + return (res + (res >> 32)) & 0x00000000000000FFul; +#endif +} -- cgit v1.2.3