mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-20 14:16:02 +00:00
![Arnaldo Carvalho de Melo](/assets/img/avatar_default.png)
Instead of accessing it directly, as it uses EXPORT_SYMBOL, that has no meaning in tools/perf and because we removed the stubs for it, i.e. we removed the tools/include/linux/export.h file. This fixes the build for the detached tarball sources cases and removes one more source of entanglement with the kernel sources. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-oyqx541o7apa2cskjhcxi6nx@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
62 lines
1.7 KiB
C
62 lines
1.7 KiB
C
#include <linux/bitops.h>
|
|
#include <asm/types.h>
|
|
|
|
/**
|
|
* 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 __sw_hweight32(unsigned int w)
|
|
{
|
|
#ifdef CONFIG_ARCH_HAS_FAST_MULTIPLIER
|
|
w -= (w >> 1) & 0x55555555;
|
|
w = (w & 0x33333333) + ((w >> 2) & 0x33333333);
|
|
w = (w + (w >> 4)) & 0x0f0f0f0f;
|
|
return (w * 0x01010101) >> 24;
|
|
#else
|
|
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;
|
|
#endif
|
|
}
|
|
|
|
unsigned int __sw_hweight16(unsigned int w)
|
|
{
|
|
unsigned int res = w - ((w >> 1) & 0x5555);
|
|
res = (res & 0x3333) + ((res >> 2) & 0x3333);
|
|
res = (res + (res >> 4)) & 0x0F0F;
|
|
return (res + (res >> 8)) & 0x00FF;
|
|
}
|
|
|
|
unsigned int __sw_hweight8(unsigned int w)
|
|
{
|
|
unsigned int res = w - ((w >> 1) & 0x55);
|
|
res = (res & 0x33) + ((res >> 2) & 0x33);
|
|
return (res + (res >> 4)) & 0x0F;
|
|
}
|
|
|
|
unsigned long __sw_hweight64(__u64 w)
|
|
{
|
|
#if BITS_PER_LONG == 32
|
|
return __sw_hweight32((unsigned int)(w >> 32)) +
|
|
__sw_hweight32((unsigned int)w);
|
|
#elif BITS_PER_LONG == 64
|
|
#ifdef CONFIG_ARCH_HAS_FAST_MULTIPLIER
|
|
w -= (w >> 1) & 0x5555555555555555ul;
|
|
w = (w & 0x3333333333333333ul) + ((w >> 2) & 0x3333333333333333ul);
|
|
w = (w + (w >> 4)) & 0x0f0f0f0f0f0f0f0ful;
|
|
return (w * 0x0101010101010101ul) >> 56;
|
|
#else
|
|
__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
|
|
#endif
|
|
}
|