[PATCH] KVM: x86: Remove duplicated calls of reverse_cpuid_check()

From: Binbin Wu
Date: Mon Feb 20 2023 - 22:22:12 EST


Remove duplicated calls of reverse_cpuid_check() in __kvm_cpu_cap_mask()
and kvm_cpu_cap_{clear, set, get}().

reverse_cpuid_check() is directly called by:
- feature_bit() / __feature_bit()
- x86_feature_cpuid()
- kvm_cpu_cap_{clear, set, get}()
- __kvm_cpu_cap_mask()
Also __kvm_cpu_cap_mask() calls x86_feature_cpuid(),
and kvm_cpu_cap_{clear, set, get}() calls __feature_bit().
It makes the direct call of reverse_cpuid_check() duplicated.

For functions call reverse_cpuid_check() twice indirectly (e.g. cpuid_entry_get()
calls both __feature_bit() and x86_feature_cpuid()), keep them as they are.

Signed-off-by: Binbin Wu <binbin.wu@xxxxxxxxxxxxxxx>
---
arch/x86/kvm/cpuid.c | 2 --
arch/x86/kvm/cpuid.h | 3 ---
2 files changed, 5 deletions(-)

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 8f8edeaf8177..f4089d7a7c4c 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -545,8 +545,6 @@ static __always_inline void __kvm_cpu_cap_mask(unsigned int leaf)
const struct cpuid_reg cpuid = x86_feature_cpuid(leaf * 32);
struct kvm_cpuid_entry2 entry;

- reverse_cpuid_check(leaf);
-
cpuid_count(cpuid.function, cpuid.index,
&entry.eax, &entry.ebx, &entry.ecx, &entry.edx);

diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h
index b1658c0de847..d781372a01e8 100644
--- a/arch/x86/kvm/cpuid.h
+++ b/arch/x86/kvm/cpuid.h
@@ -192,7 +192,6 @@ static __always_inline void kvm_cpu_cap_clear(unsigned int x86_feature)
{
unsigned int x86_leaf = __feature_leaf(x86_feature);

- reverse_cpuid_check(x86_leaf);
kvm_cpu_caps[x86_leaf] &= ~__feature_bit(x86_feature);
}

@@ -200,7 +199,6 @@ static __always_inline void kvm_cpu_cap_set(unsigned int x86_feature)
{
unsigned int x86_leaf = __feature_leaf(x86_feature);

- reverse_cpuid_check(x86_leaf);
kvm_cpu_caps[x86_leaf] |= __feature_bit(x86_feature);
}

@@ -208,7 +206,6 @@ static __always_inline u32 kvm_cpu_cap_get(unsigned int x86_feature)
{
unsigned int x86_leaf = __feature_leaf(x86_feature);

- reverse_cpuid_check(x86_leaf);
return kvm_cpu_caps[x86_leaf] & __feature_bit(x86_feature);
}


base-commit: e73ba25fdc241c06ab48a1f708a30305d6036e66
--
2.25.1