diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
---|---|---|
committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/x86_64/lib/clear_page.S |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/x86_64/lib/clear_page.S')
-rw-r--r-- | arch/x86_64/lib/clear_page.S | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/arch/x86_64/lib/clear_page.S b/arch/x86_64/lib/clear_page.S new file mode 100644 index 000000000000..30a9da458c15 --- /dev/null +++ b/arch/x86_64/lib/clear_page.S | |||
@@ -0,0 +1,50 @@ | |||
1 | /* | ||
2 | * Zero a page. | ||
3 | * rdi page | ||
4 | */ | ||
5 | .globl clear_page | ||
6 | .p2align 4 | ||
7 | clear_page: | ||
8 | xorl %eax,%eax | ||
9 | movl $4096/64,%ecx | ||
10 | .p2align 4 | ||
11 | .Lloop: | ||
12 | decl %ecx | ||
13 | #define PUT(x) movq %rax,x*8(%rdi) | ||
14 | movq %rax,(%rdi) | ||
15 | PUT(1) | ||
16 | PUT(2) | ||
17 | PUT(3) | ||
18 | PUT(4) | ||
19 | PUT(5) | ||
20 | PUT(6) | ||
21 | PUT(7) | ||
22 | leaq 64(%rdi),%rdi | ||
23 | jnz .Lloop | ||
24 | nop | ||
25 | ret | ||
26 | clear_page_end: | ||
27 | |||
28 | /* C stepping K8 run faster using the string instructions. | ||
29 | It is also a lot simpler. Use this when possible */ | ||
30 | |||
31 | #include <asm/cpufeature.h> | ||
32 | |||
33 | .section .altinstructions,"a" | ||
34 | .align 8 | ||
35 | .quad clear_page | ||
36 | .quad clear_page_c | ||
37 | .byte X86_FEATURE_K8_C | ||
38 | .byte clear_page_end-clear_page | ||
39 | .byte clear_page_c_end-clear_page_c | ||
40 | .previous | ||
41 | |||
42 | .section .altinstr_replacement,"ax" | ||
43 | clear_page_c: | ||
44 | movl $4096/8,%ecx | ||
45 | xorl %eax,%eax | ||
46 | rep | ||
47 | stosq | ||
48 | ret | ||
49 | clear_page_c_end: | ||
50 | .previous | ||