KVM: add support for Pause-Loop exit
On 03/05/2010 07:42 AM, Andy Whitcroft wrote:
> Add kernel side support for KVM Pause-Loop exit. This allows long lock
> spins in virtual machines to relinquish CPUs to other VMs.
> Zhai, Edwin (2):
> KVM: introduce kvm_vcpu_on_spin
> KVM: VMX: Add support for Pause-Loop Exiting
> arch/x86/include/asm/vmx.h | 4 +++
> arch/x86/kvm/vmx.c | 51 +++++++++++++++++++++++++++++++++++++++++++-
> include/linux/kvm_host.h | 1 +
> virt/kvm/kvm_main.c | 15 +++++++++++++
> 4 files changed, 70 insertions(+), 1 deletions(-)
These 2 clean upstream cherry-picks appear to preserve existing behavior
if the module parameters ple_gap and ple_window are _not_ set.
In general I'm not in favor of adding features at this late stage,
especially since there will be a backported kernel with this feature
with the L+1 release.
These however appear benign while providing some performance benefit, so
ACK from me. Please remember to add the upstream commit IDs.
Tim Gardner firstname.lastname@example.org
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