KVM: x86: Add tlb remote flush callback in kvm_x86_ops.

This patch is to provide a way for platforms to register hv tlb remote
flush callback and this helps to optimize operation of tlb flush
among vcpus for nested virtualization case.

Signed-off-by: Lan Tianyu <Tianyu.Lan@microsoft.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Tianyu Lan 2018-07-19 08:40:17 +00:00 committed by Paolo Bonzini
parent 60cfce4c4f
commit b08660e59d
3 changed files with 20 additions and 1 deletions

View File

@ -985,6 +985,7 @@ struct kvm_x86_ops {
void (*set_rflags)(struct kvm_vcpu *vcpu, unsigned long rflags);
void (*tlb_flush)(struct kvm_vcpu *vcpu, bool invalidate_gpa);
int (*tlb_remote_flush)(struct kvm *kvm);
/*
* Flush any TLB entries associated with the given GVA.
@ -1145,6 +1146,16 @@ static inline void kvm_arch_free_vm(struct kvm *kvm)
return kvm_x86_ops->vm_free(kvm);
}
#define __KVM_HAVE_ARCH_FLUSH_REMOTE_TLB
static inline int kvm_arch_flush_remote_tlb(struct kvm *kvm)
{
if (kvm_x86_ops->tlb_remote_flush &&
!kvm_x86_ops->tlb_remote_flush(kvm))
return 0;
else
return -ENOTSUPP;
}
int kvm_mmu_module_init(void);
void kvm_mmu_module_exit(void);

View File

@ -834,6 +834,13 @@ static inline void kvm_arch_free_vm(struct kvm *kvm)
}
#endif
#ifndef __KVM_HAVE_ARCH_FLUSH_REMOTE_TLB
static inline int kvm_arch_flush_remote_tlb(struct kvm *kvm)
{
return -ENOTSUPP;
}
#endif
#ifdef __KVM_HAVE_ARCH_NONCOHERENT_DMA
void kvm_arch_register_noncoherent_dma(struct kvm *kvm);
void kvm_arch_unregister_noncoherent_dma(struct kvm *kvm);

View File

@ -273,7 +273,8 @@ void kvm_flush_remote_tlbs(struct kvm *kvm)
* kvm_make_all_cpus_request() reads vcpu->mode. We reuse that
* barrier here.
*/
if (kvm_make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH))
if (!kvm_arch_flush_remote_tlb(kvm)
|| kvm_make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH))
++kvm->stat.remote_tlb_flush;
cmpxchg(&kvm->tlbs_dirty, dirty_count, 0);
}