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target-i386: kvm_cpu_fill_host(): No need to check xlevel2

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There's no need to check CPU xlevel2 before calling
kvm_arch_get_supported_cpuid(s, 0xC0000001, 0, R_EDX), because:

 * The kernel won't return any entry for 0xC0000000 if host CPU vendor
   is not Centaur (See kvm_dev_ioctl_get_supported_cpuid() on the kernel
   code)
 * Similarly, the kernel won't return any entry for 0xC0000001 if
   CPUID[0xC0000000].EAX is < 0xC0000001
 * kvm_arch_get_supported_cpuid() will return 0 if no entry is returned
   by the kernel for the requested leaf

For similar reasons, we can simply set x86_cpu_def->xlevel2 directly
instead of making it conditional, because it will be set to 0 CPU vendor
is not Centaur.

This will simplify the kvm_cpu_fill_host() code a little.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
[Remove unparseable comment. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Eduardo Habkost 2014-01-20 14:41:11 -02:00 committed by Paolo Bonzini
parent b73dcfb16f
commit 803a932706
1 changed files with 4 additions and 7 deletions
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11
target-i386/cpu.c
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@ -1177,13 +1177,10 @@ static void kvm_cpu_fill_host(x86_def_t *x86_cpu_def)
cpu_x86_fill_model_id(x86_cpu_def->model_id);
/* Call Centaur's CPUID instruction. */
eax = kvm_arch_get_supported_cpuid(s, 0xC0000000, 0, R_EAX);
if (eax >= 0xC0000001) {
/* Support VIA max extended level */
x86_cpu_def->xlevel2 = eax;
x86_cpu_def->features[FEAT_C000_0001_EDX] =
kvm_arch_get_supported_cpuid(s, 0xC0000001, 0, R_EDX);
}
x86_cpu_def->xlevel2 =
kvm_arch_get_supported_cpuid(s, 0xC0000000, 0, R_EAX);
x86_cpu_def->features[FEAT_C000_0001_EDX] =
kvm_arch_get_supported_cpuid(s, 0xC0000001, 0, R_EDX);
/* Other KVM-specific feature fields: */
x86_cpu_def->features[FEAT_SVM] =