linux/drivers/kvm/kvm_svm.h
Anthony Liguori 94dfbdb389 KVM: SVM: Only save/restore MSRs when needed
We only have to save/restore MSR_GS_BASE on every VMEXIT.  The rest can be
saved/restored when we leave the VCPU.  Since we don't emulate the DEBUGCTL
MSRs and the guest cannot write to them, we don't have to worry about
saving/restoring them at all.

This shaves a whopping 40% off raw vmexit costs on AMD.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2007-05-03 10:52:32 +03:00

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C

#ifndef __KVM_SVM_H
#define __KVM_SVM_H
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/list.h>
#include <asm/msr.h>
#include "svm.h"
#include "kvm.h"
static const u32 host_save_user_msrs[] = {
#ifdef CONFIG_X86_64
MSR_STAR, MSR_LSTAR, MSR_CSTAR, MSR_SYSCALL_MASK, MSR_KERNEL_GS_BASE,
MSR_FS_BASE,
#endif
MSR_IA32_SYSENTER_CS, MSR_IA32_SYSENTER_ESP, MSR_IA32_SYSENTER_EIP,
};
#define NR_HOST_SAVE_USER_MSRS ARRAY_SIZE(host_save_user_msrs)
#define NUM_DB_REGS 4
struct vcpu_svm {
struct vmcb *vmcb;
unsigned long vmcb_pa;
struct svm_cpu_data *svm_data;
uint64_t asid_generation;
unsigned long db_regs[NUM_DB_REGS];
u64 next_rip;
u64 host_user_msrs[NR_HOST_SAVE_USER_MSRS];
u64 host_gs_base;
unsigned long host_cr2;
unsigned long host_db_regs[NUM_DB_REGS];
unsigned long host_dr6;
unsigned long host_dr7;
};
#endif