2005-04-16 22:20:36 +00:00
|
|
|
/*
|
|
|
|
|
* Zero a page.
|
|
|
|
|
* rdi page
|
|
|
|
|
*/
|
|
|
|
|
.globl clear_page
|
|
|
|
|
.p2align 4
|
|
|
|
|
clear_page:
|
2006-02-03 20:51:02 +00:00
|
|
|
xorl %eax,%eax
|
|
|
|
|
movl $4096/64,%ecx
|
|
|
|
|
.p2align 4
|
|
|
|
|
.Lloop:
|
|
|
|
|
decl %ecx
|
|
|
|
|
#define PUT(x) movq %rax,x*8(%rdi)
|
|
|
|
|
movq %rax,(%rdi)
|
|
|
|
|
PUT(1)
|
|
|
|
|
PUT(2)
|
|
|
|
|
PUT(3)
|
|
|
|
|
PUT(4)
|
|
|
|
|
PUT(5)
|
|
|
|
|
PUT(6)
|
|
|
|
|
PUT(7)
|
|
|
|
|
leaq 64(%rdi),%rdi
|
|
|
|
|
jnz .Lloop
|
|
|
|
|
nop
|
|
|
|
|
ret
|
|
|
|
|
clear_page_end:
|
|
|
|
|
|
|
|
|
|
/* Some CPUs run faster using the string instructions.
|
|
|
|
|
It is also a lot simpler. Use this when possible */
|
|
|
|
|
|
|
|
|
|
#include <asm/cpufeature.h>
|
|
|
|
|
|
|
|
|
|
.section .altinstructions,"a"
|
|
|
|
|
.align 8
|
|
|
|
|
.quad clear_page
|
|
|
|
|
.quad clear_page_c
|
|
|
|
|
.byte X86_FEATURE_REP_GOOD
|
|
|
|
|
.byte clear_page_end-clear_page
|
|
|
|
|
.byte clear_page_c_end-clear_page_c
|
|
|
|
|
.previous
|
|
|
|
|
|
|
|
|
|
.section .altinstr_replacement,"ax"
|
|
|
|
|
clear_page_c:
|
2005-04-16 22:20:36 +00:00
|
|
|
movl $4096/8,%ecx
|
|
|
|
|
xorl %eax,%eax
|
|
|
|
|
rep
|
|
|
|
|
stosq
|
|
|
|
|
ret
|
2006-02-03 20:51:02 +00:00
|
|
|
clear_page_c_end:
|
|
|
|
|
.previous
|
