diff options
author | Christoffer Dall <cdall@linaro.org> | 2017-01-04 16:10:28 +0100 |
---|---|---|
committer | Christoffer Dall <christoffer.dall@linaro.org> | 2017-11-06 16:23:13 +0100 |
commit | 688c50aa72f64ca21767486e5eef876ec23e418c (patch) | |
tree | e5e2b86ee875d005308f7540692d5373eba7605f /arch/arm | |
parent | f2a2129e0ac8d8fa79c3f85425c36f6e3368f022 (diff) | |
download | linux-688c50aa72f64ca21767486e5eef876ec23e418c.tar.bz2 |
KVM: arm/arm64: Move timer save/restore out of the hyp code
As we are about to be lazy with saving and restoring the timer
registers, we prepare by moving all possible timer configuration logic
out of the hyp code. All virtual timer registers can be programmed from
EL1 and since the arch timer is always a level triggered interrupt we
can safely do this with interrupts disabled in the host kernel on the
way to the guest without taking vtimer interrupts in the host kernel
(yet).
The downside is that the cntvoff register can only be programmed from
hyp mode, so we jump into hyp mode and back to program it. This is also
safe, because the host kernel doesn't use the virtual timer in the KVM
code. It may add a little performance performance penalty, but only
until following commits where we move this operation to vcpu load/put.
Signed-off-by: Christoffer Dall <cdall@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Diffstat (limited to 'arch/arm')
-rw-r--r-- | arch/arm/include/asm/kvm_asm.h | 2 | ||||
-rw-r--r-- | arch/arm/include/asm/kvm_hyp.h | 4 | ||||
-rw-r--r-- | arch/arm/kvm/hyp/switch.c | 7 |
3 files changed, 8 insertions, 5 deletions
diff --git a/arch/arm/include/asm/kvm_asm.h b/arch/arm/include/asm/kvm_asm.h index 14d68a4d826f..36dd2962a42d 100644 --- a/arch/arm/include/asm/kvm_asm.h +++ b/arch/arm/include/asm/kvm_asm.h @@ -68,6 +68,8 @@ extern void __kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa); extern void __kvm_tlb_flush_vmid(struct kvm *kvm); extern void __kvm_tlb_flush_local_vmid(struct kvm_vcpu *vcpu); +extern void __kvm_timer_set_cntvoff(u32 cntvoff_low, u32 cntvoff_high); + extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu); extern void __init_stage2_translation(void); diff --git a/arch/arm/include/asm/kvm_hyp.h b/arch/arm/include/asm/kvm_hyp.h index 14b5903f0224..ab20ffa8b9e7 100644 --- a/arch/arm/include/asm/kvm_hyp.h +++ b/arch/arm/include/asm/kvm_hyp.h @@ -98,8 +98,8 @@ #define cntvoff_el2 CNTVOFF #define cnthctl_el2 CNTHCTL -void __timer_save_state(struct kvm_vcpu *vcpu); -void __timer_restore_state(struct kvm_vcpu *vcpu); +void __timer_enable_traps(struct kvm_vcpu *vcpu); +void __timer_disable_traps(struct kvm_vcpu *vcpu); void __vgic_v2_save_state(struct kvm_vcpu *vcpu); void __vgic_v2_restore_state(struct kvm_vcpu *vcpu); diff --git a/arch/arm/kvm/hyp/switch.c b/arch/arm/kvm/hyp/switch.c index ebd2dd46adf7..330c9ce34ba5 100644 --- a/arch/arm/kvm/hyp/switch.c +++ b/arch/arm/kvm/hyp/switch.c @@ -174,7 +174,7 @@ int __hyp_text __kvm_vcpu_run(struct kvm_vcpu *vcpu) __activate_vm(vcpu); __vgic_restore_state(vcpu); - __timer_restore_state(vcpu); + __timer_enable_traps(vcpu); __sysreg_restore_state(guest_ctxt); __banked_restore_state(guest_ctxt); @@ -191,7 +191,8 @@ again: __banked_save_state(guest_ctxt); __sysreg_save_state(guest_ctxt); - __timer_save_state(vcpu); + __timer_disable_traps(vcpu); + __vgic_save_state(vcpu); __deactivate_traps(vcpu); @@ -237,7 +238,7 @@ void __hyp_text __noreturn __hyp_panic(int cause) vcpu = (struct kvm_vcpu *)read_sysreg(HTPIDR); host_ctxt = kern_hyp_va(vcpu->arch.host_cpu_context); - __timer_save_state(vcpu); + __timer_disable_traps(vcpu); __deactivate_traps(vcpu); __deactivate_vm(vcpu); __banked_restore_state(host_ctxt); |