diff options
| author | Sean Christopherson <sean.j.christopherson@intel.com> | 2019-04-30 10:36:17 -0700 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2019-04-30 21:56:12 +0200 |
| commit | de3cd117ed2f6cb3317212f242a87ffca56c27ac (patch) | |
| tree | 975755b3eb28c6b2bf7f8ef6552ec0d6e39cca49 /arch/x86/kvm/kvm_cache_regs.h | |
| parent | 0c55671f84fffe591e8435c93a8c83286fd6b8eb (diff) | |
KVM: x86: Omit caching logic for always-available GPRs
Except for RSP and RIP, which are held in VMX's VMCS, GPRs are always
treated "available and dirtly" on both VMX and SVM, i.e. are
unconditionally loaded/saved immediately before/after VM-Enter/VM-Exit.
Eliminating the unnecessary caching code reduces the size of KVM by a
non-trivial amount, much of which comes from the most common code paths.
E.g. on x86_64, kvm_emulate_cpuid() is reduced from 342 to 182 bytes and
kvm_emulate_hypercall() from 1362 to 1143, with the total size of KVM
dropping by ~1000 bytes. With CONFIG_RETPOLINE=y, the numbers are even
more pronounced, e.g.: 353->182, 1418->1172 and well over 2000 bytes.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/kvm_cache_regs.h')
| -rw-r--r-- | arch/x86/kvm/kvm_cache_regs.h | 32 |
1 files changed, 30 insertions, 2 deletions
diff --git a/arch/x86/kvm/kvm_cache_regs.h b/arch/x86/kvm/kvm_cache_regs.h index f8f56a93358b..d179b7d7860d 100644 --- a/arch/x86/kvm/kvm_cache_regs.h +++ b/arch/x86/kvm/kvm_cache_regs.h @@ -9,6 +9,34 @@ (X86_CR4_PVI | X86_CR4_DE | X86_CR4_PCE | X86_CR4_OSFXSR \ | X86_CR4_OSXMMEXCPT | X86_CR4_LA57 | X86_CR4_PGE) +#define BUILD_KVM_GPR_ACCESSORS(lname, uname) \ +static __always_inline unsigned long kvm_##lname##_read(struct kvm_vcpu *vcpu)\ +{ \ + return vcpu->arch.regs[VCPU_REGS_##uname]; \ +} \ +static __always_inline void kvm_##lname##_write(struct kvm_vcpu *vcpu, \ + unsigned long val) \ +{ \ + vcpu->arch.regs[VCPU_REGS_##uname] = val; \ +} +BUILD_KVM_GPR_ACCESSORS(rax, RAX) +BUILD_KVM_GPR_ACCESSORS(rbx, RBX) +BUILD_KVM_GPR_ACCESSORS(rcx, RCX) +BUILD_KVM_GPR_ACCESSORS(rdx, RDX) +BUILD_KVM_GPR_ACCESSORS(rbp, RBP) +BUILD_KVM_GPR_ACCESSORS(rsi, RSI) +BUILD_KVM_GPR_ACCESSORS(rdi, RDI) +#ifdef CONFIG_X86_64 +BUILD_KVM_GPR_ACCESSORS(r8, R8) +BUILD_KVM_GPR_ACCESSORS(r9, R9) +BUILD_KVM_GPR_ACCESSORS(r10, R10) +BUILD_KVM_GPR_ACCESSORS(r11, R11) +BUILD_KVM_GPR_ACCESSORS(r12, R12) +BUILD_KVM_GPR_ACCESSORS(r13, R13) +BUILD_KVM_GPR_ACCESSORS(r14, R14) +BUILD_KVM_GPR_ACCESSORS(r15, R15) +#endif + static inline unsigned long kvm_register_read(struct kvm_vcpu *vcpu, enum kvm_reg reg) { @@ -83,8 +111,8 @@ static inline ulong kvm_read_cr4(struct kvm_vcpu *vcpu) static inline u64 kvm_read_edx_eax(struct kvm_vcpu *vcpu) { - return (kvm_register_read(vcpu, VCPU_REGS_RAX) & -1u) - | ((u64)(kvm_register_read(vcpu, VCPU_REGS_RDX) & -1u) << 32); + return (kvm_rax_read(vcpu) & -1u) + | ((u64)(kvm_rdx_read(vcpu) & -1u) << 32); } static inline void enter_guest_mode(struct kvm_vcpu *vcpu) |