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x86, UML: remove x86-specific implementations of find_first_bit

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x86 has been switched to the generic versions of find_first_bit
and find_first_zero_bit, but the original versions were retained.
This patch just removes the now unused x86-specific versions.

also update UML.

Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Alexander van Heukelum
2008-04-01 17:47:57 +02:00
committed by Ingo Molnar
parent 3a48305028
commit 5245698f66
8 changed files with 10 additions and 193 deletions
Download Patch File Download Diff File Expand all files Collapse all files

4
arch/um/Kconfig.i386
View File

@@ -39,6 +39,10 @@ config ARCH_REUSE_HOST_VSYSCALL_AREA
bool
default y
config GENERIC_FIND_FIRST_BIT
bool
default y
config GENERIC_FIND_NEXT_BIT
bool
default y

4
arch/um/Kconfig.x86_64
View File

@@ -34,6 +34,10 @@ config SMP_BROKEN
bool
default y
config GENERIC_FIND_FIRST_BIT
bool
default y
config GENERIC_FIND_NEXT_BIT
bool
default y

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

1
arch/x86/lib/Makefile
View File

@@ -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

109
arch/x86/lib/bitops_64.c
View File

@@ -1,109 +0,0 @@
#ifndef CONFIG_GENERIC_FIND_FIRST_BIT
#include <linux/bitops.h>
#undef find_first_zero_bit
#undef find_first_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);
}
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);
}
#include <linux/module.h>
EXPORT_SYMBOL(find_first_bit);
EXPORT_SYMBOL(find_first_zero_bit);
#endif