On 2020-05-26 17:28, James Morse wrote:
Hi Marc,
On 22/04/2020 13:00, Marc Zyngier wrote:
Extract the direct HW accessors for later reuse.
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 51db934702b64..46f218982df8c 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
+u64 vcpu_read_sys_reg(const struct kvm_vcpu *vcpu, int reg)
+{
+ u64 val = 0x8badf00d8badf00d;
+
+ if (!vcpu->arch.sysregs_loaded_on_cpu) {
+ goto memory_read;
}
-immediate_write:
+ if (__vcpu_read_sys_reg_from_cpu(reg, &val))
+ return val;
+
+memory_read:
+ return __vcpu_sys_reg(vcpu, reg);
+}
The goto here is a bit odd, is it just an artefact of how we got here?
That's because a lot of this changes when NV gets added to the mix,
see [1].
Is this easier on the eye?:
| u64 vcpu_read_sys_reg(const struct kvm_vcpu *vcpu, int reg)
| {
| u64 val = 0x8badf00d8badf00d;
|
| if (vcpu->arch.sysregs_loaded_on_cpu &&
| __vcpu_read_sys_reg_from_cpu(reg, &val))
| return val;
|
| return __vcpu_sys_reg(vcpu, reg);
| }
Definitely. I don't mind reworking the NV branch so that the label
gets introduced there.
+void vcpu_write_sys_reg(struct kvm_vcpu *vcpu, u64 val, int reg)
+{
+ if (!vcpu->arch.sysregs_loaded_on_cpu)
+ goto memory_write;
+
+ if (__vcpu_write_sys_reg_to_cpu(val, reg))
+ return;
+
+memory_write:
__vcpu_sys_reg(vcpu, reg) = val;
}
Again I think its clearer without the goto....
Regardless:
Reviewed-by: James Morse <james.morse@xxxxxxx>
Thanks,
M.
[1]
https://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms.git/commit/?h=kvm-arm64/nv-5.7-rc1-WIP&id=11f3217d39a602cbfac7d08064c8b31afb57348e
--
Jazz is not dead. It just smells funny...