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| author | kfraser@localhost.localdomain <kfraser@localhost.localdomain> | 2007-06-20 16:18:03 +0100 |
|---|---|---|
| committer | kfraser@localhost.localdomain <kfraser@localhost.localdomain> | 2007-06-20 16:18:03 +0100 |
| commit | 1f698f3f9f667540ee8256dc05dc41641b8859e7 (patch) | |
| tree | af14e7f51ebc59ff4100ac9af7a68eec6aebce00 /xen/arch/x86/clear_page.S | |
| parent | 340643863ba2e9d1d93f17880f5f16317974c5e6 (diff) | |
| download | xen-1f698f3f9f667540ee8256dc05dc41641b8859e7.tar.gz xen-1f698f3f9f667540ee8256dc05dc41641b8859e7.tar.bz2 xen-1f698f3f9f667540ee8256dc05dc41641b8859e7.zip | |
x86: introduce specialized clear_page()
More than doubles performance of page clearing on not too old
processors (SSE2 supported).
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Keir Fraser <keir@xensource.com>
Diffstat (limited to 'xen/arch/x86/clear_page.S')
| -rw-r--r-- | xen/arch/x86/clear_page.S | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/xen/arch/x86/clear_page.S b/xen/arch/x86/clear_page.S new file mode 100644 index 0000000000..d3e8bba915 --- /dev/null +++ b/xen/arch/x86/clear_page.S @@ -0,0 +1,26 @@ +#include <xen/config.h> +#include <asm/page.h> + +#ifdef __i386__ +#define ptr_reg %edx +#else +#define ptr_reg %rdi +#endif + +ENTRY(clear_page_sse2) +#ifdef __i386__ + mov 4(%esp), ptr_reg +#endif + mov $PAGE_SIZE/16, %ecx + xor %eax,%eax + +0: dec %ecx + movnti %eax, (ptr_reg) + movnti %eax, 4(ptr_reg) + movnti %eax, 8(ptr_reg) + movnti %eax, 12(ptr_reg) + lea 16(ptr_reg), ptr_reg + jnz 0b + + sfence + ret |