On 06/17/2011 01:20 AM, Glauber Costa wrote:Avi, you should understand this is a discussion between 3 people: One of them can do math, the other can't.To implement steal time, we need the hypervisor to pass the guest
information
about how much time was spent running other processes outside the VM.
This is per-vcpu, and using the kvmclock structure for that is an abuse
we decided not to make.
In this patchset, I am introducing a new msr, KVM_MSR_STEAL_TIME, that
holds the memory area address containing information about steal time
This patch contains the headers for it. I am keeping it separate to
facilitate
backports to people who wants to backport the kernel part but not the
hypervisor, or the other way around.
index d079aed..79c12a7 100644
--- a/Documentation/virtual/kvm/msr.txt
+++ b/Documentation/virtual/kvm/msr.txt
@@ -185,3 +185,36 @@ MSR_KVM_ASYNC_PF_EN: 0x4b564d02
Currently type 2 APF will be always delivered on the same vcpu as
type 1 was, but guest should not rely on that.
+
+MSR_KVM_STEAL_TIME: 0x4b564d03
+
+ data: 64-byte alignment physical address of a memory area which must be
+ in guest RAM, plus an enable bit in bit 0. This memory is expected to
+ hold a copy of the following structure:
+
+ struct kvm_steal_time {
+ __u64 steal;
+ __u32 version;
+ __u32 flags;
+ __u32 pad[6];
Should be 12 to be a 64-byte structure, no?