diff options
Diffstat (limited to 'arch/x86_64/lib/copy_page.S')
| -rw-r--r-- | arch/x86_64/lib/copy_page.S | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/arch/x86_64/lib/copy_page.S b/arch/x86_64/lib/copy_page.S index 621a1976940..8fa19d96a7e 100644 --- a/arch/x86_64/lib/copy_page.S +++ b/arch/x86_64/lib/copy_page.S @@ -8,7 +8,94 @@ .globl copy_page .p2align 4 copy_page: + subq $3*8,%rsp + movq %rbx,(%rsp) + movq %r12,1*8(%rsp) + movq %r13,2*8(%rsp) + + movl $(4096/64)-5,%ecx + .p2align 4 +.Loop64: + dec %rcx + + movq (%rsi), %rax + movq 8 (%rsi), %rbx + movq 16 (%rsi), %rdx + movq 24 (%rsi), %r8 + movq 32 (%rsi), %r9 + movq 40 (%rsi), %r10 + movq 48 (%rsi), %r11 + movq 56 (%rsi), %r12 + + prefetcht0 5*64(%rsi) + + movq %rax, (%rdi) + movq %rbx, 8 (%rdi) + movq %rdx, 16 (%rdi) + movq %r8, 24 (%rdi) + movq %r9, 32 (%rdi) + movq %r10, 40 (%rdi) + movq %r11, 48 (%rdi) + movq %r12, 56 (%rdi) + + leaq 64 (%rsi), %rsi + leaq 64 (%rdi), %rdi + + jnz .Loop64 + + movl $5,%ecx + .p2align 4 +.Loop2: + decl %ecx + + movq (%rsi), %rax + movq 8 (%rsi), %rbx + movq 16 (%rsi), %rdx + movq 24 (%rsi), %r8 + movq 32 (%rsi), %r9 + movq 40 (%rsi), %r10 + movq 48 (%rsi), %r11 + movq 56 (%rsi), %r12 + + movq %rax, (%rdi) + movq %rbx, 8 (%rdi) + movq %rdx, 16 (%rdi) + movq %r8, 24 (%rdi) + movq %r9, 32 (%rdi) + movq %r10, 40 (%rdi) + movq %r11, 48 (%rdi) + movq %r12, 56 (%rdi) + + leaq 64(%rdi),%rdi + leaq 64(%rsi),%rsi + + jnz .Loop2 + + movq (%rsp),%rbx + movq 1*8(%rsp),%r12 + movq 2*8(%rsp),%r13 + addq $3*8,%rsp + ret + + /* Some CPUs run faster using the string copy instructions. + It is also a lot simpler. Use this when possible */ + +#include <asm/cpufeature.h> + + .section .altinstructions,"a" + .align 8 + .quad copy_page + .quad copy_page_c + .byte X86_FEATURE_REP_GOOD + .byte copy_page_c_end-copy_page_c + .byte copy_page_c_end-copy_page_c + .previous + + .section .altinstr_replacement,"ax" +copy_page_c: movl $4096/8,%ecx rep movsq ret +copy_page_c_end: + .previous |