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mirror_zfs/lib/libspl/asm-i386/atomic.S
Brian Behlendorf 3b6425cb5b Fix atomic_sub_64() i386 assembly implementation 
The atomic_sub_64() should use sbbl instead of adcl.  In user
space these atomics are used for statistics tracking and aren't
critical which explain how this was overlooked.  The kernel
space implementation of these atomics are layered on the
architecture specific implementations provided by the kernel.

Reviewed by: Stefan Ring <stefanrin@gmail.com>
Reviewed-by: Gvozden Neskovic <neskovic@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #5671 
Closes #5717
2017-02-01 09:36:47 -08:00

837 lines
15 KiB
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/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2007 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
.ident "%Z%%M% %I% %E% SMI"
.file "%M%"
#define _ASM
#include <ia32/sys/asm_linkage.h>
ENTRY(atomic_inc_8)
ALTENTRY(atomic_inc_uchar)
movl 4(%esp), %eax
lock
incb (%eax)
ret
SET_SIZE(atomic_inc_uchar)
SET_SIZE(atomic_inc_8)
ENTRY(atomic_inc_16)
ALTENTRY(atomic_inc_ushort)
movl 4(%esp), %eax
lock
incw (%eax)
ret
SET_SIZE(atomic_inc_ushort)
SET_SIZE(atomic_inc_16)
ENTRY(atomic_inc_32)
ALTENTRY(atomic_inc_uint)
ALTENTRY(atomic_inc_ulong)
movl 4(%esp), %eax
lock
incl (%eax)
ret
SET_SIZE(atomic_inc_ulong)
SET_SIZE(atomic_inc_uint)
SET_SIZE(atomic_inc_32)
ENTRY(atomic_inc_8_nv)
ALTENTRY(atomic_inc_uchar_nv)
movl 4(%esp), %edx
movb (%edx), %al
1:
leal 1(%eax), %ecx
lock
cmpxchgb %cl, (%edx)
jne 1b
movzbl %cl, %eax
ret
SET_SIZE(atomic_inc_uchar_nv)
SET_SIZE(atomic_inc_8_nv)
ENTRY(atomic_inc_16_nv)
ALTENTRY(atomic_inc_ushort_nv)
movl 4(%esp), %edx
movw (%edx), %ax
1:
leal 1(%eax), %ecx
lock
cmpxchgw %cx, (%edx)
jne 1b
movzwl %cx, %eax
ret
SET_SIZE(atomic_inc_ushort_nv)
SET_SIZE(atomic_inc_16_nv)
ENTRY(atomic_inc_32_nv)
ALTENTRY(atomic_inc_uint_nv)
ALTENTRY(atomic_inc_ulong_nv)
movl 4(%esp), %edx
movl (%edx), %eax
1:
leal 1(%eax), %ecx
lock
cmpxchgl %ecx, (%edx)
jne 1b
movl %ecx, %eax
ret
SET_SIZE(atomic_inc_ulong_nv)
SET_SIZE(atomic_inc_uint_nv)
SET_SIZE(atomic_inc_32_nv)
/*
* NOTE: If atomic_inc_64 and atomic_inc_64_nv are ever
* separated, you need to also edit the libc i386 platform
* specific mapfile and remove the NODYNSORT attribute
* from atomic_inc_64_nv.
*/
ENTRY(atomic_inc_64)
ALTENTRY(atomic_inc_64_nv)
pushl %edi
pushl %ebx
movl 12(%esp), %edi
movl (%edi), %eax
movl 4(%edi), %edx
1:
xorl %ebx, %ebx
xorl %ecx, %ecx
incl %ebx
addl %eax, %ebx
adcl %edx, %ecx
lock
cmpxchg8b (%edi)
jne 1b
movl %ebx, %eax
movl %ecx, %edx
popl %ebx
popl %edi
ret
SET_SIZE(atomic_inc_64_nv)
SET_SIZE(atomic_inc_64)
ENTRY(atomic_dec_8)
ALTENTRY(atomic_dec_uchar)
movl 4(%esp), %eax
lock
decb (%eax)
ret
SET_SIZE(atomic_dec_uchar)
SET_SIZE(atomic_dec_8)
ENTRY(atomic_dec_16)
ALTENTRY(atomic_dec_ushort)
movl 4(%esp), %eax
lock
decw (%eax)
ret
SET_SIZE(atomic_dec_ushort)
SET_SIZE(atomic_dec_16)
ENTRY(atomic_dec_32)
ALTENTRY(atomic_dec_uint)
ALTENTRY(atomic_dec_ulong)
movl 4(%esp), %eax
lock
decl (%eax)
ret
SET_SIZE(atomic_dec_ulong)
SET_SIZE(atomic_dec_uint)
SET_SIZE(atomic_dec_32)
ENTRY(atomic_dec_8_nv)
ALTENTRY(atomic_dec_uchar_nv)
movl 4(%esp), %edx
movb (%edx), %al
1:
leal -1(%eax), %ecx
lock
cmpxchgb %cl, (%edx)
jne 1b
movzbl %cl, %eax
ret
SET_SIZE(atomic_dec_uchar_nv)
SET_SIZE(atomic_dec_8_nv)
ENTRY(atomic_dec_16_nv)
ALTENTRY(atomic_dec_ushort_nv)
movl 4(%esp), %edx
movw (%edx), %ax
1:
leal -1(%eax), %ecx
lock
cmpxchgw %cx, (%edx)
jne 1b
movzwl %cx, %eax
ret
SET_SIZE(atomic_dec_ushort_nv)
SET_SIZE(atomic_dec_16_nv)
ENTRY(atomic_dec_32_nv)
ALTENTRY(atomic_dec_uint_nv)
ALTENTRY(atomic_dec_ulong_nv)
movl 4(%esp), %edx
movl (%edx), %eax
1:
leal -1(%eax), %ecx
lock
cmpxchgl %ecx, (%edx)
jne 1b
movl %ecx, %eax
ret
SET_SIZE(atomic_dec_ulong_nv)
SET_SIZE(atomic_dec_uint_nv)
SET_SIZE(atomic_dec_32_nv)
/*
* NOTE: If atomic_dec_64 and atomic_dec_64_nv are ever
* separated, it is important to edit the libc i386 platform
* specific mapfile and remove the NODYNSORT attribute
* from atomic_dec_64_nv.
*/
ENTRY(atomic_dec_64)
ALTENTRY(atomic_dec_64_nv)
pushl %edi
pushl %ebx
movl 12(%esp), %edi
movl (%edi), %eax
movl 4(%edi), %edx
1:
xorl %ebx, %ebx
xorl %ecx, %ecx
not %ecx
not %ebx
addl %eax, %ebx
adcl %edx, %ecx
lock
cmpxchg8b (%edi)
jne 1b
movl %ebx, %eax
movl %ecx, %edx
popl %ebx
popl %edi
ret
SET_SIZE(atomic_dec_64_nv)
SET_SIZE(atomic_dec_64)
ENTRY(atomic_add_8)
ALTENTRY(atomic_add_char)
movl 4(%esp), %eax
movl 8(%esp), %ecx
lock
addb %cl, (%eax)
ret
SET_SIZE(atomic_add_char)
SET_SIZE(atomic_add_8)
ENTRY(atomic_add_16)
ALTENTRY(atomic_add_short)
movl 4(%esp), %eax
movl 8(%esp), %ecx
lock
addw %cx, (%eax)
ret
SET_SIZE(atomic_add_short)
SET_SIZE(atomic_add_16)
ENTRY(atomic_add_32)
ALTENTRY(atomic_add_int)
ALTENTRY(atomic_add_ptr)
ALTENTRY(atomic_add_long)
movl 4(%esp), %eax
movl 8(%esp), %ecx
lock
addl %ecx, (%eax)
ret
SET_SIZE(atomic_add_long)
SET_SIZE(atomic_add_ptr)
SET_SIZE(atomic_add_int)
SET_SIZE(atomic_add_32)
ENTRY(atomic_sub_8)
ALTENTRY(atomic_sub_char)
movl 4(%esp), %eax
movl 8(%esp), %ecx
lock
subb %cl, (%eax)
ret
SET_SIZE(atomic_sub_char)
SET_SIZE(atomic_sub_8)
ENTRY(atomic_sub_16)
ALTENTRY(atomic_sub_short)
movl 4(%esp), %eax
movl 8(%esp), %ecx
lock
subw %cx, (%eax)
ret
SET_SIZE(atomic_sub_short)
SET_SIZE(atomic_sub_16)
ENTRY(atomic_sub_32)
ALTENTRY(atomic_sub_int)
ALTENTRY(atomic_sub_ptr)
ALTENTRY(atomic_sub_long)
movl 4(%esp), %eax
movl 8(%esp), %ecx
lock
subl %ecx, (%eax)
ret
SET_SIZE(atomic_sub_long)
SET_SIZE(atomic_sub_ptr)
SET_SIZE(atomic_sub_int)
SET_SIZE(atomic_sub_32)
ENTRY(atomic_or_8)
ALTENTRY(atomic_or_uchar)
movl 4(%esp), %eax
movb 8(%esp), %cl
lock
orb %cl, (%eax)
ret
SET_SIZE(atomic_or_uchar)
SET_SIZE(atomic_or_8)
ENTRY(atomic_or_16)
ALTENTRY(atomic_or_ushort)
movl 4(%esp), %eax
movw 8(%esp), %cx
lock
orw %cx, (%eax)
ret
SET_SIZE(atomic_or_ushort)
SET_SIZE(atomic_or_16)
ENTRY(atomic_or_32)
ALTENTRY(atomic_or_uint)
ALTENTRY(atomic_or_ulong)
movl 4(%esp), %eax
movl 8(%esp), %ecx
lock
orl %ecx, (%eax)
ret
SET_SIZE(atomic_or_ulong)
SET_SIZE(atomic_or_uint)
SET_SIZE(atomic_or_32)
ENTRY(atomic_and_8)
ALTENTRY(atomic_and_uchar)
movl 4(%esp), %eax
movb 8(%esp), %cl
lock
andb %cl, (%eax)
ret
SET_SIZE(atomic_and_uchar)
SET_SIZE(atomic_and_8)
ENTRY(atomic_and_16)
ALTENTRY(atomic_and_ushort)
movl 4(%esp), %eax
movw 8(%esp), %cx
lock
andw %cx, (%eax)
ret
SET_SIZE(atomic_and_ushort)
SET_SIZE(atomic_and_16)
ENTRY(atomic_and_32)
ALTENTRY(atomic_and_uint)
ALTENTRY(atomic_and_ulong)
movl 4(%esp), %eax
movl 8(%esp), %ecx
lock
andl %ecx, (%eax)
ret
SET_SIZE(atomic_and_ulong)
SET_SIZE(atomic_and_uint)
SET_SIZE(atomic_and_32)
ENTRY(atomic_add_8_nv)
ALTENTRY(atomic_add_char_nv)
movl 4(%esp), %edx
movb (%edx), %al
1:
movl 8(%esp), %ecx
addb %al, %cl
lock
cmpxchgb %cl, (%edx)
jne 1b
movzbl %cl, %eax
ret
SET_SIZE(atomic_add_char_nv)
SET_SIZE(atomic_add_8_nv)
ENTRY(atomic_add_16_nv)
ALTENTRY(atomic_add_short_nv)
movl 4(%esp), %edx
movw (%edx), %ax
1:
movl 8(%esp), %ecx
addw %ax, %cx
lock
cmpxchgw %cx, (%edx)
jne 1b
movzwl %cx, %eax
ret
SET_SIZE(atomic_add_short_nv)
SET_SIZE(atomic_add_16_nv)
ENTRY(atomic_add_32_nv)
ALTENTRY(atomic_add_int_nv)
ALTENTRY(atomic_add_ptr_nv)
ALTENTRY(atomic_add_long_nv)
movl 4(%esp), %edx
movl (%edx), %eax
1:
movl 8(%esp), %ecx
addl %eax, %ecx
lock
cmpxchgl %ecx, (%edx)
jne 1b
movl %ecx, %eax
ret
SET_SIZE(atomic_add_long_nv)
SET_SIZE(atomic_add_ptr_nv)
SET_SIZE(atomic_add_int_nv)
SET_SIZE(atomic_add_32_nv)
ENTRY(atomic_sub_8_nv)
ALTENTRY(atomic_sub_char_nv)
movl 4(%esp), %edx
movb (%edx), %al
1:
movl 8(%esp), %ecx
subb %al, %cl
lock
cmpxchgb %cl, (%edx)
jne 1b
movzbl %cl, %eax
ret
SET_SIZE(atomic_sub_char_nv)
SET_SIZE(atomic_sub_8_nv)
ENTRY(atomic_sub_16_nv)
ALTENTRY(atomic_sub_short_nv)
movl 4(%esp), %edx
movw (%edx), %ax
1:
movl 8(%esp), %ecx
subw %ax, %cx
lock
cmpxchgw %cx, (%edx)
jne 1b
movzwl %cx, %eax
ret
SET_SIZE(atomic_sub_short_nv)
SET_SIZE(atomic_sub_16_nv)
ENTRY(atomic_sub_32_nv)
ALTENTRY(atomic_sub_int_nv)
ALTENTRY(atomic_sub_ptr_nv)
ALTENTRY(atomic_sub_long_nv)
movl 4(%esp), %edx
movl (%edx), %eax
1:
movl 8(%esp), %ecx
subl %eax, %ecx
lock
cmpxchgl %ecx, (%edx)
jne 1b
movl %ecx, %eax
ret
SET_SIZE(atomic_sub_long_nv)
SET_SIZE(atomic_sub_ptr_nv)
SET_SIZE(atomic_sub_int_nv)
SET_SIZE(atomic_sub_32_nv)
/*
* NOTE: If atomic_add_64 and atomic_add_64_nv are ever
* separated, it is important to edit the libc i386 platform
* specific mapfile and remove the NODYNSORT attribute
* from atomic_add_64_nv.
*/
ENTRY(atomic_add_64)
ALTENTRY(atomic_add_64_nv)
pushl %edi
pushl %ebx
movl 12(%esp), %edi
movl (%edi), %eax
movl 4(%edi), %edx
1:
movl 16(%esp), %ebx
movl 20(%esp), %ecx
addl %eax, %ebx
adcl %edx, %ecx
lock
cmpxchg8b (%edi)
jne 1b
movl %ebx, %eax
movl %ecx, %edx
popl %ebx
popl %edi
ret
SET_SIZE(atomic_add_64_nv)
SET_SIZE(atomic_add_64)
ENTRY(atomic_sub_64)
ALTENTRY(atomic_sub_64_nv)
pushl %edi
pushl %ebx
movl 12(%esp), %edi
movl (%edi), %eax
movl 4(%edi), %edx
1:
movl 16(%esp), %ebx
movl 20(%esp), %ecx
subl %eax, %ebx
sbbl %edx, %ecx
lock
cmpxchg8b (%edi)
jne 1b
movl %ebx, %eax
movl %ecx, %edx
popl %ebx
popl %edi
ret
SET_SIZE(atomic_sub_64_nv)
SET_SIZE(atomic_sub_64)
ENTRY(atomic_or_8_nv)
ALTENTRY(atomic_or_uchar_nv)
movl 4(%esp), %edx
movb (%edx), %al
1:
movl 8(%esp), %ecx
orb %al, %cl
lock
cmpxchgb %cl, (%edx)
jne 1b
movzbl %cl, %eax
ret
SET_SIZE(atomic_or_uchar_nv)
SET_SIZE(atomic_or_8_nv)
ENTRY(atomic_or_16_nv)
ALTENTRY(atomic_or_ushort_nv)
movl 4(%esp), %edx
movw (%edx), %ax
1:
movl 8(%esp), %ecx
orw %ax, %cx
lock
cmpxchgw %cx, (%edx)
jne 1b
movzwl %cx, %eax
ret
SET_SIZE(atomic_or_ushort_nv)
SET_SIZE(atomic_or_16_nv)
ENTRY(atomic_or_32_nv)
ALTENTRY(atomic_or_uint_nv)
ALTENTRY(atomic_or_ulong_nv)
movl 4(%esp), %edx
movl (%edx), %eax
1:
movl 8(%esp), %ecx
orl %eax, %ecx
lock
cmpxchgl %ecx, (%edx)
jne 1b
movl %ecx, %eax
ret
SET_SIZE(atomic_or_ulong_nv)
SET_SIZE(atomic_or_uint_nv)
SET_SIZE(atomic_or_32_nv)
/*
* NOTE: If atomic_or_64 and atomic_or_64_nv are ever
* separated, it is important to edit the libc i386 platform
* specific mapfile and remove the NODYNSORT attribute
* from atomic_or_64_nv.
*/
ENTRY(atomic_or_64)
ALTENTRY(atomic_or_64_nv)
pushl %edi
pushl %ebx
movl 12(%esp), %edi
movl (%edi), %eax
movl 4(%edi), %edx
1:
movl 16(%esp), %ebx
movl 20(%esp), %ecx
orl %eax, %ebx
orl %edx, %ecx
lock
cmpxchg8b (%edi)
jne 1b
movl %ebx, %eax
movl %ecx, %edx
popl %ebx
popl %edi
ret
SET_SIZE(atomic_or_64_nv)
SET_SIZE(atomic_or_64)
ENTRY(atomic_and_8_nv)
ALTENTRY(atomic_and_uchar_nv)
movl 4(%esp), %edx
movb (%edx), %al
1:
movl 8(%esp), %ecx
andb %al, %cl
lock
cmpxchgb %cl, (%edx)
jne 1b
movzbl %cl, %eax
ret
SET_SIZE(atomic_and_uchar_nv)
SET_SIZE(atomic_and_8_nv)
ENTRY(atomic_and_16_nv)
ALTENTRY(atomic_and_ushort_nv)
movl 4(%esp), %edx
movw (%edx), %ax
1:
movl 8(%esp), %ecx
andw %ax, %cx
lock
cmpxchgw %cx, (%edx)
jne 1b
movzwl %cx, %eax
ret
SET_SIZE(atomic_and_ushort_nv)
SET_SIZE(atomic_and_16_nv)
ENTRY(atomic_and_32_nv)
ALTENTRY(atomic_and_uint_nv)
ALTENTRY(atomic_and_ulong_nv)
movl 4(%esp), %edx
movl (%edx), %eax
1:
movl 8(%esp), %ecx
andl %eax, %ecx
lock
cmpxchgl %ecx, (%edx)
jne 1b
movl %ecx, %eax
ret
SET_SIZE(atomic_and_ulong_nv)
SET_SIZE(atomic_and_uint_nv)
SET_SIZE(atomic_and_32_nv)
/*
* NOTE: If atomic_and_64 and atomic_and_64_nv are ever
* separated, it is important to edit the libc i386 platform
* specific mapfile and remove the NODYNSORT attribute
* from atomic_and_64_nv.
*/
ENTRY(atomic_and_64)
ALTENTRY(atomic_and_64_nv)
pushl %edi
pushl %ebx
movl 12(%esp), %edi
movl (%edi), %eax
movl 4(%edi), %edx
1:
movl 16(%esp), %ebx
movl 20(%esp), %ecx
andl %eax, %ebx
andl %edx, %ecx
lock
cmpxchg8b (%edi)
jne 1b
movl %ebx, %eax
movl %ecx, %edx
popl %ebx
popl %edi
ret
SET_SIZE(atomic_and_64_nv)
SET_SIZE(atomic_and_64)
ENTRY(atomic_cas_8)
ALTENTRY(atomic_cas_uchar)
movl 4(%esp), %edx
movzbl 8(%esp), %eax
movb 12(%esp), %cl
lock
cmpxchgb %cl, (%edx)
ret
SET_SIZE(atomic_cas_uchar)
SET_SIZE(atomic_cas_8)
ENTRY(atomic_cas_16)
ALTENTRY(atomic_cas_ushort)
movl 4(%esp), %edx
movzwl 8(%esp), %eax
movw 12(%esp), %cx
lock
cmpxchgw %cx, (%edx)
ret
SET_SIZE(atomic_cas_ushort)
SET_SIZE(atomic_cas_16)
ENTRY(atomic_cas_32)
ALTENTRY(atomic_cas_uint)
ALTENTRY(atomic_cas_ulong)
ALTENTRY(atomic_cas_ptr)
movl 4(%esp), %edx
movl 8(%esp), %eax
movl 12(%esp), %ecx
lock
cmpxchgl %ecx, (%edx)
ret
SET_SIZE(atomic_cas_ptr)
SET_SIZE(atomic_cas_ulong)
SET_SIZE(atomic_cas_uint)
SET_SIZE(atomic_cas_32)
ENTRY(atomic_cas_64)
pushl %ebx
pushl %esi
movl 12(%esp), %esi
movl 16(%esp), %eax
movl 20(%esp), %edx
movl 24(%esp), %ebx
movl 28(%esp), %ecx
lock
cmpxchg8b (%esi)
popl %esi
popl %ebx
ret
SET_SIZE(atomic_cas_64)
ENTRY(atomic_swap_8)
ALTENTRY(atomic_swap_uchar)
movl 4(%esp), %edx
movzbl 8(%esp), %eax
lock
xchgb %al, (%edx)
ret
SET_SIZE(atomic_swap_uchar)
SET_SIZE(atomic_swap_8)
ENTRY(atomic_swap_16)
ALTENTRY(atomic_swap_ushort)
movl 4(%esp), %edx
movzwl 8(%esp), %eax
lock
xchgw %ax, (%edx)
ret
SET_SIZE(atomic_swap_ushort)
SET_SIZE(atomic_swap_16)
ENTRY(atomic_swap_32)
ALTENTRY(atomic_swap_uint)
ALTENTRY(atomic_swap_ptr)
ALTENTRY(atomic_swap_ulong)
movl 4(%esp), %edx
movl 8(%esp), %eax
lock
xchgl %eax, (%edx)
ret
SET_SIZE(atomic_swap_ulong)
SET_SIZE(atomic_swap_ptr)
SET_SIZE(atomic_swap_uint)
SET_SIZE(atomic_swap_32)
ENTRY(atomic_swap_64)
pushl %esi
pushl %ebx
movl 12(%esp), %esi
movl 16(%esp), %ebx
movl 20(%esp), %ecx
movl (%esi), %eax
movl 4(%esi), %edx
1:
lock
cmpxchg8b (%esi)
jne 1b
popl %ebx
popl %esi
ret
SET_SIZE(atomic_swap_64)
ENTRY(atomic_set_long_excl)
movl 4(%esp), %edx
movl 8(%esp), %ecx
xorl %eax, %eax
lock
btsl %ecx, (%edx)
jnc 1f
decl %eax
1:
ret
SET_SIZE(atomic_set_long_excl)
ENTRY(atomic_clear_long_excl)
movl 4(%esp), %edx
movl 8(%esp), %ecx
xorl %eax, %eax
lock
btrl %ecx, (%edx)
jc 1f
decl %eax
1:
ret
SET_SIZE(atomic_clear_long_excl)
/*
* NOTE: membar_enter, membar_exit, membar_producer, and
* membar_consumer are all identical routines. We define them
* separately, instead of using ALTENTRY definitions to alias them
* together, so that DTrace and debuggers will see a unique address
* for them, allowing more accurate tracing.
*/
ENTRY(membar_enter)
lock
xorl $0, (%esp)
ret
SET_SIZE(membar_enter)
ENTRY(membar_exit)
lock
xorl $0, (%esp)
ret
SET_SIZE(membar_exit)
ENTRY(membar_producer)
lock
xorl $0, (%esp)
ret
SET_SIZE(membar_producer)
ENTRY(membar_consumer)
lock
xorl $0, (%esp)
ret
SET_SIZE(membar_consumer)
#ifdef __ELF__
.section .note.GNU-stack,"",%progbits
#endif
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