| /* Written 2003 by Andi Kleen, based on a kernel by Evandro Menezes */ |
| |
| #include <linux/linkage.h> |
| #include <asm/dwarf2.h> |
| #include <asm/alternative-asm.h> |
| |
| ALIGN |
| copy_page_rep: |
| CFI_STARTPROC |
| movl $4096/8, %ecx |
| rep movsq |
| ret |
| CFI_ENDPROC |
| ENDPROC(copy_page_rep) |
| |
| /* |
| * Don't use streaming copy unless the CPU indicates X86_FEATURE_REP_GOOD. |
| * Could vary the prefetch distance based on SMP/UP. |
| */ |
| |
| ENTRY(copy_page) |
| CFI_STARTPROC |
| subq $2*8, %rsp |
| CFI_ADJUST_CFA_OFFSET 2*8 |
| movq %rbx, (%rsp) |
| CFI_REL_OFFSET rbx, 0 |
| movq %r12, 1*8(%rsp) |
| CFI_REL_OFFSET r12, 1*8 |
| |
| 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 |
| CFI_RESTORE rbx |
| movq 1*8(%rsp), %r12 |
| CFI_RESTORE r12 |
| addq $2*8, %rsp |
| CFI_ADJUST_CFA_OFFSET -2*8 |
| ret |
| .Lcopy_page_end: |
| CFI_ENDPROC |
| ENDPROC(copy_page) |
| |
| /* Some CPUs run faster using the string copy instructions. |
| It is also a lot simpler. Use this when possible */ |
| |
| #include <asm/cpufeature.h> |
| |
| .section .altinstr_replacement,"ax" |
| 1: .byte 0xeb /* jmp <disp8> */ |
| .byte (copy_page_rep - copy_page) - (2f - 1b) /* offset */ |
| 2: |
| .previous |
| .section .altinstructions,"a" |
| altinstruction_entry copy_page, 1b, X86_FEATURE_REP_GOOD, \ |
| .Lcopy_page_end-copy_page, 2b-1b |
| .previous |
