Commit fe283e5f authored by Nikolay Borisov's avatar Nikolay Borisov Committed by Anup Patel
Browse files

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: default avatarNikolay Borisov <nborisov@suse.com>
Signed-off-by: default avatarAnup Patel <anup@brainfault.org>
parent cca986fa

arch/riscv/kvm/vcpu.c

+2 −3
Original line number Diff line number Diff line
@@ -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