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| author | Jan Beulich <jbeulich@novell.com> | 2007-10-17 18:04:41 +0200 |
|---|---|---|
| committer | Thomas Gleixner <tglx@inhelltoy.tec.linutronix.de> | 2007-10-17 20:17:04 +0200 |
| commit | 32c464f5d9701db45bc1673288594e664065388e (patch) | |
| tree | 342e6e8be44bcdc5bdc3ddd0cbf1ba15a0340602 /arch/x86 | |
| parent | x86: remove duplicated vsyscall nsec update (diff) | |
| download | linux-32c464f5d9701db45bc1673288594e664065388e.tar.xz linux-32c464f5d9701db45bc1673288594e664065388e.zip | |
x86: multi-byte single instruction NOPs
Add support for and use the multi-byte NOPs recently documented to be
available on all PentiumPro and later processors.
This patch only applies cleanly on top of the "x86: misc.
constifications" patch sent earlier.
[ tglx: arch/x86 adaptation ]
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
arch/x86/kernel/alternative.c | 23 ++++++++++++++++++++++-
include/asm-x86/processor_32.h | 22 ++++++++++++++++++++++
include/asm-x86/processor_64.h | 22 ++++++++++++++++++++++
3 files changed, 66 insertions(+), 1 deletion(-)
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/kernel/alternative.c | 23 |
1 files changed, 22 insertions, 1 deletions
diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c index 8cb5dbbd9c2e..a3ae8e6c8b3b 100644 --- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -116,12 +116,31 @@ static const unsigned char *const k7_nops[ASM_NOP_MAX+1] = { }; #endif +#ifdef P6_NOP1 +asm("\t.section .rodata, \"a\"\np6nops: " + P6_NOP1 P6_NOP2 P6_NOP3 P6_NOP4 P6_NOP5 P6_NOP6 + P6_NOP7 P6_NOP8); +extern const unsigned char p6nops[]; +static const unsigned char *const p6_nops[ASM_NOP_MAX+1] = { + NULL, + p6nops, + p6nops + 1, + p6nops + 1 + 2, + p6nops + 1 + 2 + 3, + p6nops + 1 + 2 + 3 + 4, + p6nops + 1 + 2 + 3 + 4 + 5, + p6nops + 1 + 2 + 3 + 4 + 5 + 6, + p6nops + 1 + 2 + 3 + 4 + 5 + 6 + 7, +}; +#endif + #ifdef CONFIG_X86_64 extern char __vsyscall_0; static inline const unsigned char*const * find_nop_table(void) { - return k8_nops; + return boot_cpu_data.x86_vendor != X86_VENDOR_INTEL || + boot_cpu_data.x86 < 6 ? k8_nops : p6_nops; } #else /* CONFIG_X86_64 */ @@ -132,6 +151,8 @@ static const struct nop { } noptypes[] = { { X86_FEATURE_K8, k8_nops }, { X86_FEATURE_K7, k7_nops }, + { X86_FEATURE_P4, p6_nops }, + { X86_FEATURE_P3, p6_nops }, { -1, NULL } }; |