KVM: arm/arm64: Avoid work when userspace iqchips are not used
We currently check if the VM has a userspace irqchip on every exit from
the VCPU, and if so, we do some work to ensure correct timer behavior.
This is unfortunate, as we could avoid doing any work entirely, if we
didn't have to support irqchip in userspace.
Realizing the userspace irqchip on ARM is mostly a developer or hobby
feature, and is unlikely to be used in servers or other scenarios where
performance is a priority, we can use a refcounted static key to only
check the irqchip configuration when we have at least one VM that uses
an irqchip in userspace.
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
1 file changed
