1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
|
/* SPDX-License-Identifier: GPL-2.0 */
/* Written 2003 by Andi Kleen, based on a kernel by Evandro Menezes */
#include <linux/export.h>
#include <linux/linkage.h>
#include <asm/cpufeatures.h>
#include <asm/alternative.h>
/*
* Some CPUs run faster using the string copy instructions (sane microcode).
* It is also a lot simpler. Use this when possible. But, don't use streaming
* copy unless the CPU indicates X86_FEATURE_REP_GOOD. Could vary the
* prefetch distance based on SMP/UP.
*/
ALIGN
SYM_FUNC_START(copy_page)
ALTERNATIVE "jmp copy_page_regs", "", X86_FEATURE_REP_GOOD
movl $4096/8, %ecx
rep movsq
RET
SYM_FUNC_END(copy_page)
EXPORT_SYMBOL(copy_page)
SYM_FUNC_START_LOCAL(copy_page_regs)
subq $2*8, %rsp
movq %rbx, (%rsp)
movq %r12, 1*8(%rsp)
movl $(4096/64)-5, %ecx
.p2align 4
.Loop64:
dec %rcx
movq 0x8*0(%rsi), %rax
movq 0x8*1(%rsi), %rbx
movq 0x8*2(%rsi), %rdx
movq 0x8*3(%rsi), %r8
movq 0x8*4(%rsi), %r9
movq 0x8*5(%rsi), %r10
movq 0x8*6(%rsi), %r11
movq 0x8*7(%rsi), %r12
prefetcht0 5*64(%rsi)
movq %rax, 0x8*0(%rdi)
movq %rbx, 0x8*1(%rdi)
movq %rdx, 0x8*2(%rdi)
movq %r8, 0x8*3(%rdi)
movq %r9, 0x8*4(%rdi)
movq %r10, 0x8*5(%rdi)
movq %r11, 0x8*6(%rdi)
movq %r12, 0x8*7(%rdi)
leaq 64 (%rsi), %rsi
leaq 64 (%rdi), %rdi
jnz .Loop64
movl $5, %ecx
.p2align 4
.Loop2:
decl %ecx
movq 0x8*0(%rsi), %rax
movq 0x8*1(%rsi), %rbx
movq 0x8*2(%rsi), %rdx
movq 0x8*3(%rsi), %r8
movq 0x8*4(%rsi), %r9
movq 0x8*5(%rsi), %r10
movq 0x8*6(%rsi), %r11
movq 0x8*7(%rsi), %r12
movq %rax, 0x8*0(%rdi)
movq %rbx, 0x8*1(%rdi)
movq %rdx, 0x8*2(%rdi)
movq %r8, 0x8*3(%rdi)
movq %r9, 0x8*4(%rdi)
movq %r10, 0x8*5(%rdi)
movq %r11, 0x8*6(%rdi)
movq %r12, 0x8*7(%rdi)
leaq 64(%rdi), %rdi
leaq 64(%rsi), %rsi
jnz .Loop2
movq (%rsp), %rbx
movq 1*8(%rsp), %r12
addq $2*8, %rsp
RET
SYM_FUNC_END(copy_page_regs)
|
