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authorH. Peter Anvin <hpa@zytor.com>2008-08-18 17:50:33 -0700
committerH. Peter Anvin <hpa@zytor.com>2008-09-05 16:14:01 -0700
commitf31d731e4467e61de51d7f6d7115f3b712d9354c (patch)
treed64b75a4f80d6fc3138bf29446496f95f2f484aa
parentb6734c35af028f06772c0b2c836c7d579e6d4dad (diff)
downloadop-kernel-dev-f31d731e4467e61de51d7f6d7115f3b712d9354c.zip
op-kernel-dev-f31d731e4467e61de51d7f6d7115f3b712d9354c.tar.gz
x86: use X86_FEATURE_NOPL in alternatives
Use X86_FEATURE_NOPL to determine if it is safe to use P6 NOPs in alternatives. Also, replace table and loop with simple if statement. Signed-off-by: H. Peter Anvin <hpa@zytor.com>
-rw-r--r--arch/x86/kernel/alternative.c36
1 files changed, 13 insertions, 23 deletions
diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index 2763cb3..65a0c1b 100644
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -145,35 +145,25 @@ static const unsigned char *const p6_nops[ASM_NOP_MAX+1] = {
extern char __vsyscall_0;
const unsigned char *const *find_nop_table(void)
{
- return boot_cpu_data.x86_vendor != X86_VENDOR_INTEL ||
- boot_cpu_data.x86 < 6 ? k8_nops : p6_nops;
+ if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL &&
+ boot_cpu_has(X86_FEATURE_NOPL))
+ return p6_nops;
+ else
+ return k8_nops;
}
#else /* CONFIG_X86_64 */
-static const struct nop {
- int cpuid;
- const unsigned char *const *noptable;
-} noptypes[] = {
- { X86_FEATURE_K8, k8_nops },
- { X86_FEATURE_K7, k7_nops },
- { X86_FEATURE_P4, p6_nops },
- { X86_FEATURE_P3, p6_nops },
- { -1, NULL }
-};
-
const unsigned char *const *find_nop_table(void)
{
- const unsigned char *const *noptable = intel_nops;
- int i;
-
- for (i = 0; noptypes[i].cpuid >= 0; i++) {
- if (boot_cpu_has(noptypes[i].cpuid)) {
- noptable = noptypes[i].noptable;
- break;
- }
- }
- return noptable;
+ if (boot_cpu_has(X86_FEATURE_K8))
+ return k8_nops;
+ else if (boot_cpu_has(X86_FEATURE_K7))
+ return k7_nops;
+ else if (boot_cpu_has(X86_FEATURE_NOPL))
+ return p6_nops;
+ else
+ return intel_nops;
}
#endif /* CONFIG_X86_64 */
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