diff options
author | Sean Christopherson <seanjc@google.com> | 2023-02-11 03:35:33 +0300 |
---|---|---|
committer | Paolo Bonzini <pbonzini@redhat.com> | 2023-03-14 17:28:57 +0300 |
commit | 19f10315fd53599d8186aa46a0363b233292eb3d (patch) | |
tree | bb3ad465263d06bed265805dce9dcf782ed32cc5 /arch/x86/kvm/vmx/hyperv.h | |
parent | 68ac4221497b9a54f32c452a774ae747da908a81 (diff) | |
download | linux-19f10315fd53599d8186aa46a0363b233292eb3d.tar.xz |
KVM: VMX: Stub out enable_evmcs static key for CONFIG_HYPERV=n
Wrap enable_evmcs in a helper and stub it out when CONFIG_HYPERV=n in
order to eliminate the static branch nop placeholders. clang-14 is clever
enough to elide the nop, but gcc-12 is not. Stubbing out the key reduces
the size of kvm-intel.ko by ~7.5% (200KiB) when compiled with gcc-12
(there are a _lot_ of VMCS accesses throughout KVM).
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230211003534.564198-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/vmx/hyperv.h')
-rw-r--r-- | arch/x86/kvm/vmx/hyperv.h | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/arch/x86/kvm/vmx/hyperv.h b/arch/x86/kvm/vmx/hyperv.h index 1299143d00df..a54a2fdf0a5b 100644 --- a/arch/x86/kvm/vmx/hyperv.h +++ b/arch/x86/kvm/vmx/hyperv.h @@ -16,8 +16,6 @@ struct vmcs_config; -DECLARE_STATIC_KEY_FALSE(enable_evmcs); - #define current_evmcs ((struct hv_enlightened_vmcs *)this_cpu_read(current_vmcs)) #define KVM_EVMCS_VERSION 1 @@ -69,6 +67,13 @@ static inline u64 evmcs_read_any(struct hv_enlightened_vmcs *evmcs, #if IS_ENABLED(CONFIG_HYPERV) +DECLARE_STATIC_KEY_FALSE(enable_evmcs); + +static __always_inline bool kvm_is_using_evmcs(void) +{ + return static_branch_unlikely(&enable_evmcs); +} + static __always_inline int get_evmcs_offset(unsigned long field, u16 *clean_field) { @@ -158,6 +163,7 @@ static inline void evmcs_load(u64 phys_addr) void evmcs_sanitize_exec_ctrls(struct vmcs_config *vmcs_conf); #else /* !IS_ENABLED(CONFIG_HYPERV) */ +static __always_inline bool kvm_is_using_evmcs(void) { return false; } static __always_inline void evmcs_write64(unsigned long field, u64 value) {} static __always_inline void evmcs_write32(unsigned long field, u32 value) {} static __always_inline void evmcs_write16(unsigned long field, u16 value) {} |