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Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-generic-bitops-v3 

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-generic-bitops-v3:
  x86, bitops: select the generic bitmap search functions
  x86: include/asm-x86/pgalloc.h/bitops.h: checkpatch cleanups - formatting only
  x86: finalize bitops unification
  x86, UML: remove x86-specific implementations of find_first_bit
  x86: optimize find_first_bit for small bitmaps
  x86: switch 64-bit to generic find_first_bit
  x86: generic versions of find_first_(zero_)bit, convert i386
  bitops: use __fls for fls64 on 64-bit archs
  generic: implement __fls on all 64-bit archs
  generic: introduce a generic __fls implementation
  x86: merge the simple bitops and move them to bitops.h
  x86, generic: optimize find_next_(zero_)bit for small constant-size bitmaps
  x86, uml: fix uml with generic find_next_bit for x86
  x86: change x86 to use generic find_next_bit
  uml: Kconfig cleanup
  uml: fix build error
This commit is contained in:
Linus Torvalds 2008-04-26 13:46:11 -07:00
parent a52b0d25a7 19870def58
commit 9b79ed952b
26 changed files with 467 additions and 603 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
arch/um/Kconfig.x86_64
View File

@ -1,3 +1,10 @@
menu "Host processor type and features"
source "arch/x86/Kconfig.cpu"
endmenu
config UML_X86
bool
default y

1
arch/um/os-Linux/helper.c
View File

@ -14,6 +14,7 @@
#include "os.h"
#include "um_malloc.h"
#include "user.h"
#include <linux/limits.h>
struct helper_data {
void (*pre_exec)(void*);

2
arch/um/sys-i386/Makefile
View File

@ -6,7 +6,7 @@ obj-y = bug.o bugs.o checksum.o delay.o fault.o ksyms.o ldt.o ptrace.o \
ptrace_user.o setjmp.o signal.o stub.o stub_segv.o syscalls.o sysrq.o \
sys_call_table.o tls.o
subarch-obj-y = lib/bitops_32.o lib/semaphore_32.o lib/string_32.o
subarch-obj-y = lib/semaphore_32.o lib/string_32.o
subarch-obj-$(CONFIG_HIGHMEM) += mm/highmem_32.o
subarch-obj-$(CONFIG_MODULES) += kernel/module_32.o

2
arch/um/sys-x86_64/Makefile
View File

@ -10,7 +10,7 @@ obj-y = bug.o bugs.o delay.o fault.o ldt.o mem.o ptrace.o ptrace_user.o \
obj-$(CONFIG_MODULES) += um_module.o
subarch-obj-y = lib/bitops_64.o lib/csum-partial_64.o lib/memcpy_64.o lib/thunk_64.o
subarch-obj-y = lib/csum-partial_64.o lib/memcpy_64.o lib/thunk_64.o
subarch-obj-$(CONFIG_MODULES) += kernel/module_64.o
ldt-y = ../sys-i386/ldt.o

7
arch/x86/Kconfig.cpu
View File

@ -278,6 +278,11 @@ config GENERIC_CPU
endchoice
config X86_CPU
def_bool y
select GENERIC_FIND_FIRST_BIT
select GENERIC_FIND_NEXT_BIT
config X86_GENERIC
bool "Generic x86 support"
depends on X86_32
@ -398,7 +403,7 @@ config X86_TSC
# generates cmov.
config X86_CMOV
def_bool y
depends on (MK7 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MVIAC3_2 || MVIAC7)
depends on (MK7 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MVIAC3_2 || MVIAC7 || X86_64)
config X86_MINIMUM_CPU_FAMILY
int

3
arch/x86/lib/Makefile
View File

@ -11,7 +11,7 @@ lib-y += memcpy_$(BITS).o
ifeq ($(CONFIG_X86_32),y)
lib-y += checksum_32.o
lib-y += strstr_32.o
lib-y += bitops_32.o semaphore_32.o string_32.o
lib-y += semaphore_32.o string_32.o
lib-$(CONFIG_X86_USE_3DNOW) += mmx_32.o
else
@ -21,7 +21,6 @@ else
lib-y += csum-partial_64.o csum-copy_64.o csum-wrappers_64.o
lib-y += thunk_64.o clear_page_64.o copy_page_64.o
lib-y += bitops_64.o
lib-y += memmove_64.o memset_64.o
lib-y += copy_user_64.o rwlock_64.o copy_user_nocache_64.o
endif

70
arch/x86/lib/bitops_32.c
View File

@ -1,70 +0,0 @@
#include <linux/bitops.h>
#include <linux/module.h>
/**
* find_next_bit - find the next set bit in a memory region
* @addr: The address to base the search on
* @offset: The bitnumber to start searching at
* @size: The maximum size to search
*/
int find_next_bit(const unsigned long *addr, int size, int offset)
{
const unsigned long *p = addr + (offset >> 5);
int set = 0, bit = offset & 31, res;
if (bit) {
/*
* Look for nonzero in the first 32 bits:
*/
__asm__("bsfl %1,%0\n\t"
"jne 1f\n\t"
"movl $32, %0\n"
"1:"
: "=r" (set)
: "r" (*p >> bit));
if (set < (32 - bit))
return set + offset;
set = 32 - bit;
p++;
}
/*
* No set bit yet, search remaining full words for a bit
*/
res = find_first_bit (p, size - 32 * (p - addr));
return (offset + set + res);
}
EXPORT_SYMBOL(find_next_bit);
/**
* find_next_zero_bit - find the first zero bit in a memory region
* @addr: The address to base the search on
* @offset: The bitnumber to start searching at
* @size: The maximum size to search
*/
int find_next_zero_bit(const unsigned long *addr, int size, int offset)
{
const unsigned long *p = addr + (offset >> 5);
int set = 0, bit = offset & 31, res;
if (bit) {
/*
* Look for zero in the first 32 bits.
*/
__asm__("bsfl %1,%0\n\t"
"jne 1f\n\t"
"movl $32, %0\n"
"1:"
: "=r" (set)
: "r" (~(*p >> bit)));
if (set < (32 - bit))
return set + offset;
set = 32 - bit;
p++;
}
/*
* No zero yet, search remaining full bytes for a zero
*/
res = find_first_zero_bit(p, size - 32 * (p - addr));
return (offset + set + res);
}
EXPORT_SYMBOL(find_next_zero_bit);

175
arch/x86/lib/bitops_64.c
View File

@ -1,175 +0,0 @@
#include <linux/bitops.h>
#undef find_first_zero_bit
#undef find_next_zero_bit
#undef find_first_bit
#undef find_next_bit
static inline long
__find_first_zero_bit(const unsigned long * addr, unsigned long size)
{
long d0, d1, d2;
long res;
/*
* We must test the size in words, not in bits, because
* otherwise incoming sizes in the range -63..-1 will not run
* any scasq instructions, and then the flags used by the je
* instruction will have whatever random value was in place
* before. Nobody should call us like that, but
* find_next_zero_bit() does when offset and size are at the
* same word and it fails to find a zero itself.
*/
size += 63;
size >>= 6;
if (!size)
return 0;
asm volatile(
" repe; scasq\n"
" je 1f\n"
" xorq -8(%%rdi),%%rax\n"
" subq $8,%%rdi\n"
" bsfq %%rax,%%rdx\n"
"1: subq %[addr],%%rdi\n"
" shlq $3,%%rdi\n"
" addq %%rdi,%%rdx"
:"=d" (res), "=&c" (d0), "=&D" (d1), "=&a" (d2)
:"0" (0ULL), "1" (size), "2" (addr), "3" (-1ULL),
[addr] "S" (addr) : "memory");
/*
* Any register would do for [addr] above, but GCC tends to
* prefer rbx over rsi, even though rsi is readily available
* and doesn't have to be saved.
*/
return res;
}
/**
* find_first_zero_bit - find the first zero bit in a memory region
* @addr: The address to start the search at
* @size: The maximum size to search
*
* Returns the bit-number of the first zero bit, not the number of the byte
* containing a bit.
*/
long find_first_zero_bit(const unsigned long * addr, unsigned long size)
{
return __find_first_zero_bit (addr, size);
}
/**
* find_next_zero_bit - find the next zero bit in a memory region
* @addr: The address to base the search on
* @offset: The bitnumber to start searching at
* @size: The maximum size to search
*/
long find_next_zero_bit (const unsigned long * addr, long size, long offset)
{
const unsigned long * p = addr + (offset >> 6);
unsigned long set = 0;
unsigned long res, bit = offset&63;
if (bit) {
/*
* Look for zero in first word
*/
asm("bsfq %1,%0\n\t"
"cmoveq %2,%0"
: "=r" (set)
: "r" (~(*p >> bit)), "r"(64L));
if (set < (64 - bit))
return set + offset;
set = 64 - bit;
p++;
}
/*
* No zero yet, search remaining full words for a zero
*/
res = __find_first_zero_bit (p, size - 64 * (p - addr));
return (offset + set + res);
}
static inline long
__find_first_bit(const unsigned long * addr, unsigned long size)
{
long d0, d1;
long res;
/*
* We must test the size in words, not in bits, because
* otherwise incoming sizes in the range -63..-1 will not run
* any scasq instructions, and then the flags used by the jz
* instruction will have whatever random value was in place
* before. Nobody should call us like that, but
* find_next_bit() does when offset and size are at the same
* word and it fails to find a one itself.
*/
size += 63;
size >>= 6;
if (!size)
return 0;
asm volatile(
" repe; scasq\n"
" jz 1f\n"
" subq $8,%%rdi\n"
" bsfq (%%rdi),%%rax\n"
"1: subq %[addr],%%rdi\n"
" shlq $3,%%rdi\n"
" addq %%rdi,%%rax"
:"=a" (res), "=&c" (d0), "=&D" (d1)
:"0" (0ULL), "1" (size), "2" (addr),
[addr] "r" (addr) : "memory");
return res;
}
/**
* find_first_bit - find the first set bit in a memory region
* @addr: The address to start the search at
* @size: The maximum size to search
*
* Returns the bit-number of the first set bit, not the number of the byte
* containing a bit.
*/
long find_first_bit(const unsigned long * addr, unsigned long size)
{
return __find_first_bit(addr,size);
}
/**
* find_next_bit - find the first set bit in a memory region
* @addr: The address to base the search on
* @offset: The bitnumber to start searching at
* @size: The maximum size to search
*/
long find_next_bit(const unsigned long * addr, long size, long offset)
{
const unsigned long * p = addr + (offset >> 6);
unsigned long set = 0, bit = offset & 63, res;
if (bit) {
/*
* Look for nonzero in the first 64 bits:
*/
asm("bsfq %1,%0\n\t"
"cmoveq %2,%0\n\t"
: "=r" (set)
: "r" (*p >> bit), "r" (64L));
if (set < (64 - bit))
return set + offset;
set = 64 - bit;
p++;
}
/*
* No set bit yet, search remaining full words for a bit
*/
res = __find_first_bit (p, size - 64 * (p - addr));
return (offset + set + res);
}
#include <linux/module.h>
EXPORT_SYMBOL(find_next_bit);
EXPORT_SYMBOL(find_first_bit);
EXPORT_SYMBOL(find_first_zero_bit);
EXPORT_SYMBOL(find_next_zero_bit);

5
include/asm-alpha/bitops.h
View File

@ -388,6 +388,11 @@ static inline int fls64(unsigned long x)
}
#endif
static inline unsigned long __fls(unsigned long x)
{
return fls64(x) - 1;
}
static inline int fls(int x)
{
return fls64((unsigned int) x);

43
include/asm-generic/bitops/__fls.h Normal file
View File

@ -0,0 +1,43 @@
#ifndef _ASM_GENERIC_BITOPS___FLS_H_
#define _ASM_GENERIC_BITOPS___FLS_H_
#include <asm/types.h>
/**
* __fls - find last (most-significant) set bit in a long word
* @word: the word to search
*
* Undefined if no set bit exists, so code should check against 0 first.
*/
static inline unsigned long __fls(unsigned long word)
{
int num = BITS_PER_LONG - 1;
#if BITS_PER_LONG == 64
if (!(word & (~0ul << 32))) {
num -= 32;
word <<= 32;
}
#endif
if (!(word & (~0ul << (BITS_PER_LONG-16)))) {
num -= 16;
word <<= 16;
}
if (!(word & (~0ul << (BITS_PER_LONG-8)))) {
num -= 8;
word <<= 8;
}
if (!(word & (~0ul << (BITS_PER_LONG-4)))) {
num -= 4;
word <<= 4;
}
if (!(word & (~0ul << (BITS_PER_LONG-2)))) {
num -= 2;
word <<= 2;
}
if (!(word & (~0ul << (BITS_PER_LONG-1))))
num -= 1;
return num;
}
#endif /* _ASM_GENERIC_BITOPS___FLS_H_ */

2
include/asm-generic/bitops/find.h
View File

@ -1,11 +1,13 @@
#ifndef _ASM_GENERIC_BITOPS_FIND_H_
#define _ASM_GENERIC_BITOPS_FIND_H_
#ifndef CONFIG_GENERIC_FIND_NEXT_BIT
extern unsigned long find_next_bit(const unsigned long *addr, unsigned long
size, unsigned long offset);
extern unsigned long find_next_zero_bit(const unsigned long *addr, unsigned
long size, unsigned long offset);
#endif
#define find_first_bit(addr, size) find_next_bit((addr), (size), 0)
#define find_first_zero_bit(addr, size) find_next_zero_bit((addr), (size), 0)

22
include/asm-generic/bitops/fls64.h
View File

@ -3,6 +3,18 @@
#include <asm/types.h>
/**
* fls64 - find last set bit in a 64-bit word
* @x: the word to search
*
* This is defined in a similar way as the libc and compiler builtin
* ffsll, but returns the position of the most significant set bit.
*
* fls64(value) returns 0 if value is 0 or the position of the last
* set bit if value is nonzero. The last (most significant) bit is
* at position 64.
*/
#if BITS_PER_LONG == 32
static inline int fls64(__u64 x)
{
__u32 h = x >> 32;
@ -10,5 +22,15 @@ static inline int fls64(__u64 x)
return fls(h) + 32;
return fls(x);
}
#elif BITS_PER_LONG == 64
static inline int fls64(__u64 x)
{
if (x == 0)
return 0;
return __fls(x) + 1;
}
#else
#error BITS_PER_LONG not 32 or 64
#endif
#endif /* _ASM_GENERIC_BITOPS_FLS64_H_ */

16
include/asm-ia64/bitops.h
View File

@ -407,6 +407,22 @@ fls (int t)
return ia64_popcnt(x);
}
/*
* Find the last (most significant) bit set. Undefined for x==0.
* Bits are numbered from 0..63 (e.g., __fls(9) == 3).
*/
static inline unsigned long
__fls (unsigned long x)
{
x |= x >> 1;
x |= x >> 2;
x |= x >> 4;
x |= x >> 8;
x |= x >> 16;
x |= x >> 32;
return ia64_popcnt(x) - 1;
}
#include <asm-generic/bitops/fls64.h>
/*

5
include/asm-mips/bitops.h
View File

@ -591,6 +591,11 @@ static inline int __ilog2(unsigned long x)
return 63 - lz;
}
static inline unsigned long __fls(unsigned long x)
{
return __ilog2(x);
}
#if defined(CONFIG_CPU_MIPS32) || defined(CONFIG_CPU_MIPS64)
/*

1
include/asm-parisc/bitops.h
View File

@ -210,6 +210,7 @@ static __inline__ int fls(int x)
return ret;
}
#include <asm-generic/bitops/__fls.h>
#include <asm-generic/bitops/fls64.h>
#include <asm-generic/bitops/hweight.h>
#include <asm-generic/bitops/lock.h>

5
include/asm-powerpc/bitops.h
View File

@ -313,6 +313,11 @@ static __inline__ int fls(unsigned int x)
return 32 - lz;
}
static __inline__ unsigned long __fls(unsigned long x)
{
return __ilog2(x);
}
/*
* 64-bit can do this using one cntlzd (count leading zeroes doubleword)
* instruction; for 32-bit we use the generic version, which does two

1
include/asm-s390/bitops.h
View File

@ -769,6 +769,7 @@ static inline int sched_find_first_bit(unsigned long *b)
}
#include <asm-generic/bitops/fls.h>
#include <asm-generic/bitops/__fls.h>
#include <asm-generic/bitops/fls64.h>
#include <asm-generic/bitops/hweight.h>

1
include/asm-sh/bitops.h
View File

@ -95,6 +95,7 @@ static inline unsigned long ffz(unsigned long word)
#include <asm-generic/bitops/ext2-atomic.h>
#include <asm-generic/bitops/minix.h>
#include <asm-generic/bitops/fls.h>
#include <asm-generic/bitops/__fls.h>
#include <asm-generic/bitops/fls64.h>
#endif /* __KERNEL__ */

1
include/asm-sparc64/bitops.h
View File

@ -34,6 +34,7 @@ extern void change_bit(unsigned long nr, volatile unsigned long *addr);
#include <asm-generic/bitops/ffz.h>
#include <asm-generic/bitops/__ffs.h>
#include <asm-generic/bitops/fls.h>
#include <asm-generic/bitops/__fls.h>
#include <asm-generic/bitops/fls64.h>
#ifdef __KERNEL__

149
include/asm-x86/bitops.h
View File

@ -62,12 +62,9 @@ static inline void set_bit(int nr, volatile void *addr)
*/
static inline void __set_bit(int nr, volatile void *addr)
{
asm volatile("bts %1,%0"
: ADDR
: "Ir" (nr) : "memory");
asm volatile("bts %1,%0" : ADDR : "Ir" (nr) : "memory");
}
/**
* clear_bit - Clears a bit in memory
* @nr: Bit to clear
@ -297,19 +294,145 @@ static inline int variable_test_bit(int nr, volatile const void *addr)
static int test_bit(int nr, const volatile unsigned long *addr);
#endif
#define test_bit(nr,addr) \
(__builtin_constant_p(nr) ? \
constant_test_bit((nr),(addr)) : \
variable_test_bit((nr),(addr)))
#define test_bit(nr, addr) \
(__builtin_constant_p((nr)) \
? constant_test_bit((nr), (addr)) \
: variable_test_bit((nr), (addr)))
/**
* __ffs - find first set 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)
{
asm("bsf %1,%0"
: "=r" (word)
: "rm" (word));
return word;
}
/**
* ffz - find first zero bit in word
* @word: The word to search
*
* Undefined if no zero exists, so code should check against ~0UL first.
*/
static inline unsigned long ffz(unsigned long word)
{
asm("bsf %1,%0"
: "=r" (word)
: "r" (~word));
return word;
}
/*
* __fls: find last set bit in word
* @word: The word to search
*
* Undefined if no zero exists, so code should check against ~0UL first.
*/
static inline unsigned long __fls(unsigned long word)
{
asm("bsr %1,%0"
: "=r" (word)
: "rm" (word));
return word;
}
#ifdef __KERNEL__
/**
* ffs - find first set bit in word
* @x: the word to search
*
* This is defined the same way as the libc and compiler builtin ffs
* routines, therefore differs in spirit from the other bitops.
*
* ffs(value) returns 0 if value is 0 or the position of the first
* set bit if value is nonzero. The first (least significant) bit
* is at position 1.
*/
static inline int ffs(int x)
{
int r;
#ifdef CONFIG_X86_CMOV
asm("bsfl %1,%0\n\t"
"cmovzl %2,%0"
: "=r" (r) : "rm" (x), "r" (-1));
#else
asm("bsfl %1,%0\n\t"
"jnz 1f\n\t"
"movl $-1,%0\n"
"1:" : "=r" (r) : "rm" (x));
#endif
return r + 1;
}
/**
* fls - find last set bit in word
* @x: the word to search
*
* This is defined in a similar way as the libc and compiler builtin
* ffs, but returns the position of the most significant set bit.
*
* fls(value) returns 0 if value is 0 or the position of the last
* set bit if value is nonzero. The last (most significant) bit is
* at position 32.
*/
static inline int fls(int x)
{
int r;
#ifdef CONFIG_X86_CMOV
asm("bsrl %1,%0\n\t"
"cmovzl %2,%0"
: "=&r" (r) : "rm" (x), "rm" (-1));
#else
asm("bsrl %1,%0\n\t"
"jnz 1f\n\t"
"movl $-1,%0\n"
"1:" : "=r" (r) : "rm" (x));
#endif
return r + 1;
}
#endif /* __KERNEL__ */
#undef BASE_ADDR
#undef BIT_ADDR
#undef ADDR
#ifdef CONFIG_X86_32
# include "bitops_32.h"
#else
# include "bitops_64.h"
#endif
static inline void set_bit_string(unsigned long *bitmap,
unsigned long i, int len)
{
unsigned long end = i + len;
while (i < end) {
__set_bit(i, bitmap);
i++;
}
}
#ifdef __KERNEL__
#include <asm-generic/bitops/sched.h>
#define ARCH_HAS_FAST_MULTIPLIER 1
#include <asm-generic/bitops/hweight.h>
#endif /* __KERNEL__ */
#include <asm-generic/bitops/fls64.h>
#ifdef __KERNEL__
#include <asm-generic/bitops/ext2-non-atomic.h>
#define ext2_set_bit_atomic(lock, nr, addr) \
test_and_set_bit((nr), (unsigned long *)(addr))
#define ext2_clear_bit_atomic(lock, nr, addr) \
test_and_clear_bit((nr), (unsigned long *)(addr))
#include <asm-generic/bitops/minix.h>
#endif /* __KERNEL__ */
#endif /* _ASM_X86_BITOPS_H */

166
include/asm-x86/bitops_32.h
View File

@ -1,166 +0,0 @@
#ifndef _I386_BITOPS_H
#define _I386_BITOPS_H
/*
* Copyright 1992, Linus Torvalds.
*/
/**
* find_first_zero_bit - find the first zero bit in a memory region
* @addr: The address to start the search at
* @size: The maximum size to search
*
* Returns the bit number of the first zero bit, not the number of the byte
* containing a bit.
*/
static inline int find_first_zero_bit(const unsigned long *addr, unsigned size)
{
int d0, d1, d2;
int res;
if (!size)
return 0;
/* This looks at memory.
* Mark it volatile to tell gcc not to move it around
*/
asm volatile("movl $-1,%%eax\n\t"
"xorl %%edx,%%edx\n\t"
"repe; scasl\n\t"
"je 1f\n\t"
"xorl -4(%%edi),%%eax\n\t"
"subl $4,%%edi\n\t"
"bsfl %%eax,%%edx\n"
"1:\tsubl %%ebx,%%edi\n\t"
"shll $3,%%edi\n\t"
"addl %%edi,%%edx"
: "=d" (res), "=&c" (d0), "=&D" (d1), "=&a" (d2)
: "1" ((size + 31) >> 5), "2" (addr),
"b" (addr) : "memory");
return res;
}
/**
* find_next_zero_bit - find the first zero bit in a memory region
* @addr: The address to base the search on
* @offset: The bit number to start searching at
* @size: The maximum size to search
*/
int find_next_zero_bit(const unsigned long *addr, int size, int offset);
/**
* __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)
{
__asm__("bsfl %1,%0"
:"=r" (word)
:"rm" (word));
return word;
}
/**
* find_first_bit - find the first set bit in a memory region
* @addr: The address to start the search at
* @size: The maximum size to search
*
* Returns the bit number of the first set bit, not the number of the byte
* containing a bit.
*/
static inline unsigned find_first_bit(const unsigned long *addr, unsigned size)
{
unsigned x = 0;
while (x < size) {
unsigned long val = *addr++;
if (val)
return __ffs(val) + x;
x += sizeof(*addr) << 3;
}
return x;
}
/**
* find_next_bit - find the first set bit in a memory region
* @addr: The address to base the search on
* @offset: The bit number to start searching at
* @size: The maximum size to search
*/
int find_next_bit(const unsigned long *addr, int size, int offset);
/**
* ffz - find first zero in word.
* @word: The word to search
*
* Undefined if no zero exists, so code should check against ~0UL first.
*/
static inline unsigned long ffz(unsigned long word)
{
__asm__("bsfl %1,%0"
:"=r" (word)
:"r" (~word));
return word;
}
#ifdef __KERNEL__
#include <asm-generic/bitops/sched.h>
/**
* ffs - find first bit set
* @x: the word to search
*
* This is defined the same way as
* the libc and compiler builtin ffs routines, therefore
* differs in spirit from the above ffz() (man ffs).
*/
static inline int ffs(int x)
{
int r;
__asm__("bsfl %1,%0\n\t"
"jnz 1f\n\t"
"movl $-1,%0\n"
"1:" : "=r" (r) : "rm" (x));
return r+1;
}
/**
* fls - find last bit set
* @x: the word to search
*
* This is defined the same way as ffs().
*/
static inline int fls(int x)
{
int r;
__asm__("bsrl %1,%0\n\t"
"jnz 1f\n\t"
"movl $-1,%0\n"
"1:" : "=r" (r) : "rm" (x));
return r+1;
}
#include <asm-generic/bitops/hweight.h>
#endif /* __KERNEL__ */
#include <asm-generic/bitops/fls64.h>
#ifdef __KERNEL__
#include <asm-generic/bitops/ext2-non-atomic.h>
#define ext2_set_bit_atomic(lock, nr, addr) \
test_and_set_bit((nr), (unsigned long *)(addr))
#define ext2_clear_bit_atomic(lock, nr, addr) \
test_and_clear_bit((nr), (unsigned long *)(addr))
#include <asm-generic/bitops/minix.h>
#endif /* __KERNEL__ */
#endif /* _I386_BITOPS_H */

162
include/asm-x86/bitops_64.h
View File

@ -1,162 +0,0 @@
#ifndef _X86_64_BITOPS_H
#define _X86_64_BITOPS_H
/*
* Copyright 1992, Linus Torvalds.
*/
extern long find_first_zero_bit(const unsigned long *addr, unsigned long size);
extern long find_next_zero_bit(const unsigned long *addr, long size, long offset);
extern long find_first_bit(const unsigned long *addr, unsigned long size);
extern long find_next_bit(const unsigned long *addr, long size, long offset);
/* return index of first bet set in val or max when no bit is set */
static inline long __scanbit(unsigned long val, unsigned long max)
{
asm("bsfq %1,%0 ; cmovz %2,%0" : "=&r" (val) : "r" (val), "r" (max));
return val;
}
#define find_next_bit(addr,size,off) \
((__builtin_constant_p(size) && (size) <= BITS_PER_LONG ? \
((off) + (__scanbit((*(unsigned long *)addr) >> (off),(size)-(off)))) : \
find_next_bit(addr,size,off)))
#define find_next_zero_bit(addr,size,off) \
((__builtin_constant_p(size) && (size) <= BITS_PER_LONG ? \
((off)+(__scanbit(~(((*(unsigned long *)addr)) >> (off)),(size)-(off)))) : \
find_next_zero_bit(addr,size,off)))
#define find_first_bit(addr, size) \
((__builtin_constant_p((size)) && (size) <= BITS_PER_LONG \
? (__scanbit(*(unsigned long *)(addr), (size))) \
: find_first_bit((addr), (size))))
#define find_first_zero_bit(addr, size) \
((__builtin_constant_p((size)) && (size) <= BITS_PER_LONG \
? (__scanbit(~*(unsigned long *)(addr), (size))) \
: find_first_zero_bit((addr), (size))))
static inline void set_bit_string(unsigned long *bitmap, unsigned long i,
int len)
{
unsigned long end = i + len;
while (i < end) {
__set_bit(i, bitmap);
i++;
}
}
/**
* ffz - find first zero in word.
* @word: The word to search
*
* Undefined if no zero exists, so code should check against ~0UL first.
*/
static inline unsigned long ffz(unsigned long word)
{
__asm__("bsfq %1,%0"
:"=r" (word)
:"r" (~word));
return word;
}
/**
* __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)
{
__asm__("bsfq %1,%0"
:"=r" (word)
:"rm" (word));
return word;
}
/*
* __fls: find last bit set.
* @word: The word to search
*
* Undefined if no zero exists, so code should check against ~0UL first.
*/
static inline unsigned long __fls(unsigned long word)
{
__asm__("bsrq %1,%0"
:"=r" (word)
:"rm" (word));
return word;
}
#ifdef __KERNEL__
#include <asm-generic/bitops/sched.h>
/**
* ffs - find first bit set
* @x: the word to search
*
* This is defined the same way as
* the libc and compiler builtin ffs routines, therefore
* differs in spirit from the above ffz (man ffs).
*/
static inline int ffs(int x)
{
int r;
__asm__("bsfl %1,%0\n\t"
"cmovzl %2,%0"
: "=r" (r) : "rm" (x), "r" (-1));
return r+1;
}
/**
* fls64 - find last bit set in 64 bit word
* @x: the word to search
*
* This is defined the same way as fls.
*/
static inline int fls64(__u64 x)
{
if (x == 0)
return 0;
return __fls(x) + 1;
}
/**
* fls - find last bit set
* @x: the word to search
*
* This is defined the same way as ffs.
*/
static inline int fls(int x)
{
int r;
__asm__("bsrl %1,%0\n\t"
"cmovzl %2,%0"
: "=&r" (r) : "rm" (x), "rm" (-1));
return r+1;
}
#define ARCH_HAS_FAST_MULTIPLIER 1
#include <asm-generic/bitops/hweight.h>
#endif /* __KERNEL__ */
#ifdef __KERNEL__
#include <asm-generic/bitops/ext2-non-atomic.h>
#define ext2_set_bit_atomic(lock, nr, addr) \
test_and_set_bit((nr), (unsigned long *)(addr))
#define ext2_clear_bit_atomic(lock, nr, addr) \
test_and_clear_bit((nr), (unsigned long *)(addr))
#include <asm-generic/bitops/minix.h>
#endif /* __KERNEL__ */
#endif /* _X86_64_BITOPS_H */

140
include/linux/bitops.h
View File

@ -112,4 +112,144 @@ static inline unsigned fls_long(unsigned long l)
return fls64(l);
}
#ifdef __KERNEL__
#ifdef CONFIG_GENERIC_FIND_FIRST_BIT
extern unsigned long __find_first_bit(const unsigned long *addr,
unsigned long size);
/**
* find_first_bit - find the first set bit in a memory region
* @addr: The address to start the search at
* @size: The maximum size to search
*
* Returns the bit number of the first set bit.
*/
static __always_inline unsigned long
find_first_bit(const unsigned long *addr, unsigned long size)
{
/* Avoid a function call if the bitmap size is a constant */
/* and not bigger than BITS_PER_LONG. */
/* insert a sentinel so that __ffs returns size if there */
/* are no set bits in the bitmap */
if (__builtin_constant_p(size) && (size < BITS_PER_LONG))
return __ffs((*addr) | (1ul << size));
/* the result of __ffs(0) is undefined, so it needs to be */
/* handled separately */
if (__builtin_constant_p(size) && (size == BITS_PER_LONG))
return ((*addr) == 0) ? BITS_PER_LONG : __ffs(*addr);
/* size is not constant or too big */
return __find_first_bit(addr, size);
}
extern unsigned long __find_first_zero_bit(const unsigned long *addr,
unsigned long size);
/**
* find_first_zero_bit - find the first cleared bit in a memory region
* @addr: The address to start the search at
* @size: The maximum size to search
*
* Returns the bit number of the first cleared bit.
*/
static __always_inline unsigned long
find_first_zero_bit(const unsigned long *addr, unsigned long size)
{
/* Avoid a function call if the bitmap size is a constant */
/* and not bigger than BITS_PER_LONG. */
/* insert a sentinel so that __ffs returns size if there */
/* are no set bits in the bitmap */
if (__builtin_constant_p(size) && (size < BITS_PER_LONG)) {
return __ffs(~(*addr) | (1ul << size));
}
/* the result of __ffs(0) is undefined, so it needs to be */
/* handled separately */
if (__builtin_constant_p(size) && (size == BITS_PER_LONG))
return (~(*addr) == 0) ? BITS_PER_LONG : __ffs(~(*addr));
/* size is not constant or too big */
return __find_first_zero_bit(addr, size);
}
#endif /* CONFIG_GENERIC_FIND_FIRST_BIT */
#ifdef CONFIG_GENERIC_FIND_NEXT_BIT
extern unsigned long __find_next_bit(const unsigned long *addr,
unsigned long size, unsigned long offset);
/**
* find_next_bit - find the next set bit in a memory region
* @addr: The address to base the search on
* @offset: The bitnumber to start searching at
* @size: The bitmap size in bits
*/
static __always_inline unsigned long
find_next_bit(const unsigned long *addr, unsigned long size,
unsigned long offset)
{
unsigned long value;
/* Avoid a function call if the bitmap size is a constant */
/* and not bigger than BITS_PER_LONG. */
/* insert a sentinel so that __ffs returns size if there */
/* are no set bits in the bitmap */
if (__builtin_constant_p(size) && (size < BITS_PER_LONG)) {
value = (*addr) & ((~0ul) << offset);
value |= (1ul << size);
return __ffs(value);
}
/* the result of __ffs(0) is undefined, so it needs to be */
/* handled separately */
if (__builtin_constant_p(size) && (size == BITS_PER_LONG)) {
value = (*addr) & ((~0ul) << offset);
return (value == 0) ? BITS_PER_LONG : __ffs(value);
}
/* size is not constant or too big */
return __find_next_bit(addr, size, offset);
}
extern unsigned long __find_next_zero_bit(const unsigned long *addr,
unsigned long size, unsigned long offset);
/**
* find_next_zero_bit - find the next cleared bit in a memory region
* @addr: The address to base the search on
* @offset: The bitnumber to start searching at
* @size: The bitmap size in bits
*/
static __always_inline unsigned long
find_next_zero_bit(const unsigned long *addr, unsigned long size,
unsigned long offset)
{
unsigned long value;
/* Avoid a function call if the bitmap size is a constant */
/* and not bigger than BITS_PER_LONG. */
/* insert a sentinel so that __ffs returns size if there */
/* are no set bits in the bitmap */
if (__builtin_constant_p(size) && (size < BITS_PER_LONG)) {
value = (~(*addr)) & ((~0ul) << offset);
value |= (1ul << size);
return __ffs(value);
}
/* the result of __ffs(0) is undefined, so it needs to be */
/* handled separately */
if (__builtin_constant_p(size) && (size == BITS_PER_LONG)) {
value = (~(*addr)) & ((~0ul) << offset);
return (value == 0) ? BITS_PER_LONG : __ffs(value);
}
/* size is not constant or too big */
return __find_next_zero_bit(addr, size, offset);
}
#endif /* CONFIG_GENERIC_FIND_NEXT_BIT */
#endif /* __KERNEL__ */
#endif

6
lib/Kconfig
View File

@ -7,6 +7,12 @@ menu "Library routines"
config BITREVERSE
tristate
config GENERIC_FIND_FIRST_BIT
def_bool n
config GENERIC_FIND_NEXT_BIT
def_bool n
config CRC_CCITT
tristate "CRC-CCITT functions"
help

1
lib/Makefile
View File

@ -29,6 +29,7 @@ obj-$(CONFIG_DEBUG_LOCKING_API_SELFTESTS) += locking-selftest.o
obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock_debug.o
lib-$(CONFIG_RWSEM_GENERIC_SPINLOCK) += rwsem-spinlock.o
lib-$(CONFIG_RWSEM_XCHGADD_ALGORITHM) += rwsem.o
lib-$(CONFIG_GENERIC_FIND_FIRST_BIT) += find_next_bit.o
lib-$(CONFIG_GENERIC_FIND_NEXT_BIT) += find_next_bit.o
obj-$(CONFIG_GENERIC_HWEIGHT) += hweight.o
obj-$(CONFIG_LOCK_KERNEL) += kernel_lock.o

77
lib/find_next_bit.c
View File

@ -16,14 +16,12 @@
#define BITOP_WORD(nr) ((nr) / BITS_PER_LONG)
/**
* find_next_bit - find the next set bit in a memory region
* @addr: The address to base the search on
* @offset: The bitnumber to start searching at
* @size: The maximum size to search
#ifdef CONFIG_GENERIC_FIND_NEXT_BIT
/*
* Find the next set bit in a memory region.
*/
unsigned long find_next_bit(const unsigned long *addr, unsigned long size,
unsigned long offset)
unsigned long __find_next_bit(const unsigned long *addr,
unsigned long size, unsigned long offset)
{
const unsigned long *p = addr + BITOP_WORD(offset);
unsigned long result = offset & ~(BITS_PER_LONG-1);
@ -60,15 +58,14 @@ unsigned long find_next_bit(const unsigned long *addr, unsigned long size,
found_middle:
return result + __ffs(tmp);
}
EXPORT_SYMBOL(find_next_bit);
EXPORT_SYMBOL(__find_next_bit);
/*
* This implementation of find_{first,next}_zero_bit was stolen from
* Linus' asm-alpha/bitops.h.
*/
unsigned long find_next_zero_bit(const unsigned long *addr, unsigned long size,
unsigned long offset)
unsigned long __find_next_zero_bit(const unsigned long *addr,
unsigned long size, unsigned long offset)
{
const unsigned long *p = addr + BITOP_WORD(offset);
unsigned long result = offset & ~(BITS_PER_LONG-1);
@ -105,8 +102,64 @@ unsigned long find_next_zero_bit(const unsigned long *addr, unsigned long size,
found_middle:
return result + ffz(tmp);
}
EXPORT_SYMBOL(__find_next_zero_bit);
#endif /* CONFIG_GENERIC_FIND_NEXT_BIT */
EXPORT_SYMBOL(find_next_zero_bit);
#ifdef CONFIG_GENERIC_FIND_FIRST_BIT
/*
* Find the first set bit in a memory region.
*/
unsigned long __find_first_bit(const unsigned long *addr,
unsigned long size)
{
const unsigned long *p = addr;
unsigned long result = 0;
unsigned long tmp;
while (size & ~(BITS_PER_LONG-1)) {
if ((tmp = *(p++)))
goto found;
result += BITS_PER_LONG;
size -= BITS_PER_LONG;
}
if (!size)
return result;
tmp = (*p) & (~0UL >> (BITS_PER_LONG - size));
if (tmp == 0UL) /* Are any bits set? */
return result + size; /* Nope. */
found:
return result + __ffs(tmp);
}
EXPORT_SYMBOL(__find_first_bit);
/*
* Find the first cleared bit in a memory region.
*/
unsigned long __find_first_zero_bit(const unsigned long *addr,
unsigned long size)
{
const unsigned long *p = addr;
unsigned long result = 0;
unsigned long tmp;
while (size & ~(BITS_PER_LONG-1)) {
if (~(tmp = *(p++)))
goto found;
result += BITS_PER_LONG;
size -= BITS_PER_LONG;
}
if (!size)
return result;
tmp = (*p) | (~0UL << size);
if (tmp == ~0UL) /* Are any bits zero? */
return result + size; /* Nope. */
found:
return result + ffz(tmp);
}
EXPORT_SYMBOL(__find_first_zero_bit);
#endif /* CONFIG_GENERIC_FIND_FIRST_BIT */
#ifdef __BIG_ENDIAN