RISC-V: KVM: move preempt_disable() call in kvm_arch_vcpu_ioctl_run

local_irq_disable provides stronger guarantees than preempt_disable so
calling the latter is redundant when interrupts are disabled. Instead,
explicitly disable preemption right before interrupts are enabled/disabled
to ensure that the time accounted in guest_timing_exit_irqoff
includes time taken by the guest or interrupts.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Anup Patel <anup@brainfault.org>

arch/riscv/kvm/vcpu.c

@@ -936,8 +936,6 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
 
 		kvm_riscv_check_vcpu_requests(vcpu);
 
-		preempt_disable();
-
 		local_irq_disable();
 
 		/*
@@ -974,7 +972,6 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
 		    kvm_request_pending(vcpu)) {
 			vcpu->mode = OUTSIDE_GUEST_MODE;
 			local_irq_enable();
-			preempt_enable();
 			kvm_vcpu_srcu_read_lock(vcpu);
 			continue;
 		}
@@ -1008,6 +1005,8 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
 		/* Syncup interrupts state with HW */
 		kvm_riscv_vcpu_sync_interrupts(vcpu);
 
+		preempt_disable();
+
 		/*
 		 * We must ensure that any pending interrupts are taken before
 		 * we exit guest timing so that timer ticks are accounted as