Commit f62eb9ca authored by Bibo Mao's avatar Bibo Mao Committed by Huacai Chen
Browse files

LoongArch: KVM: Move host CSR_EENTRY save and restore in context switch 



CSR register LOONGARCH_CSR_EENTRY is shared between host CPU and guest
vCPU, KVM need save and restore LOONGARCH_CSR_EENTRY register. Here move
LOONGARCH_CSR_EENTRY saving in to context switch function rather than VM
entry.

At most time VM enter/exit is much more frequent than vCPU thread context
switch.

Signed-off-by: default avatarBibo Mao <maobibo@loongson.cn>
Signed-off-by: default avatarHuacai Chen <chenhuacai@loongson.cn>
parent 14d2714d

arch/loongarch/kvm/vcpu.c

+4 −3
Original line number Diff line number Diff line
@@ -320,7 +320,6 @@ static int kvm_pre_enter_guest(struct kvm_vcpu *vcpu) 
		 * and it may also clear KVM_REQ_TLB_FLUSH_GPA pending bit

		 */

		kvm_late_check_requests(vcpu);

		vcpu->arch.host_eentry = csr_read64(LOONGARCH_CSR_EENTRY);

		/* Clear KVM_LARCH_SWCSR_LATEST as CSR will change when enter guest */

		vcpu->arch.aux_inuse &= ~KVM_LARCH_SWCSR_LATEST;
@@ -1628,9 +1627,11 @@ static int _kvm_vcpu_load(struct kvm_vcpu *vcpu, int cpu) 
	 * If not, any old guest state from this vCPU will have been clobbered.

	 */

	context = per_cpu_ptr(vcpu->kvm->arch.vmcs, cpu);

	if (migrated || (context->last_vcpu != vcpu))

		vcpu->arch.aux_inuse &= ~KVM_LARCH_HWCSR_USABLE;

	if (migrated || (context->last_vcpu != vcpu)) {

		context->last_vcpu = vcpu;

		vcpu->arch.aux_inuse &= ~KVM_LARCH_HWCSR_USABLE;

		vcpu->arch.host_eentry = csr_read64(LOONGARCH_CSR_EENTRY);

	}



	/* Restore timer state regardless */

	kvm_restore_timer(vcpu);