tools: Move __ffs implementation to tools/include/asm-generic/bitops/__ffs.h

To match the Linux kernel source code structure from where this code came from.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-gubysnp4a8hd98lxoeruak13@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Arnaldo Carvalho de Melo 2014-12-15 15:07:24 -03:00
parent 8185e881f9
commit 2dc0b97219
4 changed files with 46 additions and 36 deletions

View file

@ -0,0 +1,43 @@
#ifndef _TOOLS_LINUX_ASM_GENERIC_BITOPS___FFS_H_
#define _TOOLS_LINUX_ASM_GENERIC_BITOPS___FFS_H_
#include <asm/types.h>
/**
* __ffs - find first bit in word.
* @word: The word to search
*
* Undefined if no bit exists, so code should check against 0 first.
*/
static __always_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 /* _TOOLS_LINUX_ASM_GENERIC_BITOPS___FFS_H_ */

View file

@ -5,6 +5,7 @@ tools/lib/api
tools/lib/symbol/kallsyms.c
tools/lib/symbol/kallsyms.h
tools/include/asm/bug.h
tools/include/asm-generic/bitops/__ffs.h
tools/include/linux/compiler.h
tools/include/linux/hash.h
tools/include/linux/export.h

View file

@ -232,6 +232,7 @@ LIB_H += ../include/linux/hash.h
LIB_H += ../../include/linux/stringify.h
LIB_H += util/include/linux/bitmap.h
LIB_H += util/include/linux/bitops.h
LIB_H += ../include/asm-generic/bitops/__ffs.h
LIB_H += ../include/linux/compiler.h
LIB_H += util/include/linux/const.h
LIB_H += util/include/linux/ctype.h

View file

@ -52,42 +52,7 @@ static inline unsigned long hweight_long(unsigned long w)
#define BITOP_WORD(nr) ((nr) / BITS_PER_LONG)
/**
* __ffs - find first bit in word.
* @word: The word to search
*
* Undefined if no bit exists, so code should check against 0 first.
*/
static __always_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;
}
#include <asm-generic/bitops/__ffs.h>
typedef const unsigned long __attribute__((__may_alias__)) long_alias_t;