Re: [PATCH v3 0/5] hw/arm/virt: Introduce kvm-steal-time

[Andrew Jones]

Hi Peter, Eric, and other interested parties,

Here's a gentle ping for reviewers.

Thanks,
drew

On Wed, Sep 16, 2020 at 11:26:15AM +0200, Andrew Jones wrote:
> Previous posting:
> https://www.mail-archive.com/qemu-devel@nongnu.org/msg727588.html
> 
> v3:
>   - Rebased: 5.2 machine type and kvm32 drop now included
>   - Switched to using new KVM cap that has been merged upstream
>   - Picked up some r-b's and some of Eric's comments from v2
> 
> KVM supports the ability to publish the amount of time that VCPUs
> were runnable, but not running due to other host threads running
> instead, to the guest. The guest scheduler may use that information
> when making decisions and the guest may expose it to its userspace
> (Linux publishes this information in /proc/stat). This feature is
> called "steal time" as it represents the amount of time stolen from
> a guest by scheduling out its VCPUs. To enable this feature KVM
> userspace must provide a memory region that will be used to publish
> the information to the guest. The memory region is typical migratable
> region. The GPA of the region is given to KVM through a VCPU device
> ioctl interface. This feature is only available for 64-bit guests
> per the Arm PVTIME specification (DEN0057A).
> 
> This series provides the QEMU support of this feature. It will
> be enabled by default for 5.2 machine types and later, but may
> be disabled with a new CPU property "kvm-steal-time".
> 
> Thanks,
> drew
> 
> 
> Andrew Jones (5):
>   target/arm/kvm: Make uncalled stubs explicitly unreachable
>   hw/arm/virt: Move post cpu realize check into its own function
>   hw/arm/virt: Move kvm pmu setup to virt_cpu_post_init
>   DO NOT MERGE: HACK: Add steal time KVM cap to kvm.h
>   hw/arm/virt: Implement kvm-steal-time
> 
>  docs/system/arm/cpu-features.rst |  11 ++++
>  hw/arm/virt.c                    | 110 ++++++++++++++++++++++---------
>  include/hw/arm/virt.h            |   5 ++
>  linux-headers/linux/kvm.h        |   1 +
>  target/arm/cpu.c                 |   8 +++
>  target/arm/cpu.h                 |   4 ++
>  target/arm/kvm.c                 |  16 +++++
>  target/arm/kvm64.c               |  64 ++++++++++++++++--
>  target/arm/kvm_arm.h             |  94 ++++++++++++++++++++------
>  target/arm/monitor.c             |   2 +-
>  tests/qtest/arm-cpu-features.c   |  25 +++++--
>  11 files changed, 281 insertions(+), 59 deletions(-)
> 
> -- 
> 2.26.2
>