| Message ID | 20200916092620.19161-1-drjones@redhat.com |
|---|---|
| Headers | show |
| Series | hw/arm/virt: Introduce kvm-steal-time | expand |
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 >
On Tue, Sep 29, 2020 at 04:47:33PM +0200, Andrew Jones wrote: > > Hi Peter, Eric, and other interested parties, > > Here's a gentle ping for reviewers. Thanks for the review Eric! I'll send a Linux header update patch and a rebase of this series with R-b's. drew > > 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 > > > >