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| #include <linux/linkage.h>
| #include <asm/export.h>
|
| /*
| * Most CPUs support enhanced REP MOVSB/STOSB instructions. It is
| * recommended to use this when possible and we do use them by default.
| * If enhanced REP MOVSB/STOSB is not available, try to use fast string.
| * Otherwise, use original.
| */
|
| /*
| * Zero a page.
| * %rdi - page
| */
| ENTRY(clear_page_rep)
| movl $4096/8,%ecx
| xorl %eax,%eax
| rep stosq
| ret
| ENDPROC(clear_page_rep)
| EXPORT_SYMBOL_GPL(clear_page_rep)
|
| ENTRY(clear_page_orig)
| 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
| ENDPROC(clear_page_orig)
| EXPORT_SYMBOL_GPL(clear_page_orig)
|
| ENTRY(clear_page_erms)
| movl $4096,%ecx
| xorl %eax,%eax
| rep stosb
| ret
| ENDPROC(clear_page_erms)
| EXPORT_SYMBOL_GPL(clear_page_erms)
|
|
