Re: [PATCH V4 00/10] Add architecture agnostic code to support vCPU Hotplug

[Vishnu Pajjuri]

Hi Salil,

On 10-10-2023 02:05, Salil Mehta wrote:

> Virtual CPU hotplug support is being added across various architectures[1][3].
> This series adds various code bits common across all architectures:
>
> 1. vCPU creation and Parking code refactor [Patch 1]
> 2. Update ACPI GED framework to support vCPU Hotplug [Patch 4,6,7]
> 3. ACPI CPUs AML code change [Patch 5]
> 4. Helper functions to support unrealization of CPU objects [Patch 8,9]
> 5. Misc [Patch 2,3,10]
>
>
> Repository:
>
> [*] https://github.com/salil-mehta/qemu.git virt-cpuhp-armv8/rfc-v2.common.v4
>
>
> Revision History:
>
> RFC V3 -> RFC V4
> 1. Addressed David Hilderbrand's comments
>    - Fixed the wrong doc comment of kvm_park_vcpu API prototype
>    - Added Reviewed-by tags for patches {2,4}
> Link: 20231009112812.10612-1-salil.mehta@huawei.com/">https://lore.kernel.org/qemu-devel/20231009112812.10612-1-salil.mehta@huawei.com/
>
> RFC V2 -> RFC V3
> 1. Addressed Jonathan Cameron's comments
>    - Fixed 'vcpu-id' type wrongly changed from 'unsigned long' to 'integer'
>    - Removed unnecessary use of variable 'vcpu_id' in kvm_park_vcpu
>    - Updated [Patch V2 03/10] commit-log with details of ACPI_CPU_SCAN_METHOD macro
>    - Updated [Patch V2 05/10] commit-log with details of conditional event handler method
>    - Added Reviewed-by tags for patches {2,3,4,6,7}
> 2. Addressed Gavin Shan's comments
>    - Remove unnecessary use of variable 'vcpu_id' in kvm_par_vcpu
>    - Fixed return value in kvm_get_vcpu from -1 to -ENOENT
>    - Reset the value of 'gdb_num_g_regs' in gdb_unregister_coprocessor_all
>    - Fixed the kvm_{create,park}_vcpu prototypes docs
>    - Added Reviewed-by tags for patches {2,3,4,5,6,7,9,10}
> 3. Addressed one earlier missed comment by Alex Bennée in RFC V1
>    - Added traces instead of DPRINTF in the newly added and some existing functions
> Link: https://lore.kernel.org/qemu-devel/20230930001933.2660-1-salil.mehta@huawei.com/
>
> RFC V1 -> RFC V2
> 1. Addressed Alex Bennée's comments
>    - Refactored the kvm_create_vcpu logic to get rid of goto
>    - Added the docs for kvm_{create,park}_vcpu prototypes
>    - Splitted the gdbstub and AddressSpace destruction change into separate patches
>    - Added Reviewed-by tags for patches {2,10}
> Link: https://lore.kernel.org/qemu-devel/20230929124304.13672-1-salil.mehta@huawei.com/
>
> References:
>
> [1] https://lore.kernel.org/qemu-devel/20230926100436.28284-1-salil.mehta@huawei.com/
> [2] https://lore.kernel.org/all/20230913163823.7880-1-james.morse@arm.com/
> [3] https://lore.kernel.org/qemu-devel/cover.1695697701.git.lixianglai@loongson.cn/
>
>
> Jean-Philippe Brucker (1):
>   target/arm/kvm: Write CPU state back to KVM on reset
>
> Salil Mehta (9):
>   accel/kvm: Extract common KVM vCPU {creation,parking} code
>   hw/acpi: Move CPU ctrl-dev MMIO region len macro to common header file
>   hw/acpi: Add ACPI CPU hotplug init stub
>   hw/acpi: Init GED framework with CPU hotplug events
>   hw/acpi: Update CPUs AML with cpu-(ctrl)dev change
>   hw/acpi: Update GED _EVT method AML with CPU scan
>   hw/acpi: Update ACPI GED framework to support vCPU Hotplug
>   physmem: Add helper function to destroy CPU AddressSpace
>   gdbstub: Add helper function to unregister GDB register space
>
>  accel/kvm/kvm-all.c                    | 64 ++++++++++++++++++++------
>  accel/kvm/trace-events                 |  4 ++
>  gdbstub/gdbstub.c                      | 15 ++++++
>  hw/acpi/acpi-cpu-hotplug-stub.c        |  6 +++
>  hw/acpi/cpu.c                          | 27 +++++++----
>  hw/acpi/generic_event_device.c         | 22 +++++++++
>  hw/i386/acpi-build.c                   |  2 +-
>  include/exec/cpu-common.h              |  8 ++++
>  include/exec/gdbstub.h                 |  5 ++
>  include/hw/acpi/cpu.h                  |  5 +-
>  include/hw/acpi/cpu_hotplug.h          |  4 ++
>  include/hw/acpi/generic_event_device.h |  5 ++
>  include/hw/core/cpu.h                  |  1 +
>  include/sysemu/kvm.h                   | 16 +++++++
>  softmmu/physmem.c                      | 25 ++++++++++
>  target/arm/kvm.c                       |  8 +++-
>  16 files changed, 189 insertions(+), 28 deletions(-)
>

Tested sanity cases on Ampere's platform.
Also tested VM live migration.

Tested-by: Vishnu Pajjuri <vishnu@os.amperecomputing.com>

Regards,

-Vishnu

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