Re: [PATCH v7 10/10] arm64: Retrieve stolen time as paravirtualized guest

[Catalin Marinas]

On Mon, Oct 21, 2019 at 04:28:23PM +0100, Steven Price wrote:
> Enable paravirtualization features when running under a hypervisor
> supporting the PV_TIME_ST hypercall.
> 
> For each (v)CPU, we ask the hypervisor for the location of a shared
> page which the hypervisor will use to report stolen time to us. We set
> pv_time_ops to the stolen time function which simply reads the stolen
> value from the shared page for a VCPU. We guarantee single-copy
> atomicity using READ_ONCE which means we can also read the stolen
> time for another VCPU than the currently running one while it is
> potentially being updated by the hypervisor.
> 
> Signed-off-by: Steven Price <steven.price@xxxxxxx>

Acked-by: Catalin Marinas <catalin.marinas@xxxxxxx>