Re: [PATCH V8 0/8] Add architecture agnostic code to support vCPU Hotplug

["Michael S. Tsirkin" <mst@redhat.com>]

On Tue, Mar 12, 2024 at 01:59:52AM +0000, 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 2,3]
> 3. ACPI CPUs AML code change [Patch 4,5]
> 4. Helper functions to support unrealization of CPU objects [Patch 6,7]
> 5. Docs [Patch 8]


I replied separately: patch 1 needs ack from KVM maintainers.

I suspect I could pick some bits I have no way to know
whether they were tested separately.
In any way looks like something best left to next release ...

> 
> Repository:
> 
> [*] https://github.com/salil-mehta/qemu.git virt-cpuhp-armv8/rfc-v2.common.v8
> 
> 
> Revision History:
> 
> Patch-set V7 -> V8
> 
> 1. Rebased and Fixed the conflicts
> 
> Patch-set  V6 -> V7
> 1. Addressed Alex Bennée's comments
>    - Updated the docs
> 2. Addressed Igor Mammedov's comments
>    - Merged patches [Patch V6 3/9] & [Patch V6 7/9] with [Patch V6 4/9]
>    - Updated commit-log of [Patch V6 1/9] and [Patch V6 5/9]     
> 3. Added Shaoqin Huang's Reviewed-by tags for whole series.
> Link: https://lore.kernel.org/qemu-devel/20231013105129.25648-1-salil.mehta@huawei.com/
> 
> Patch-set  V5 -> V6
> 1. Addressed Gavin Shan's comments
>    - Fixed the assert() ranges of address spaces
>    - Rebased the patch-set to latest changes in the qemu.git
>    - Added Reviewed-by tags for patches {8,9}
> 2. Addressed Jonathan Cameron's comments
>    - Updated commit-log for [Patch V5 1/9] with mention of trace events
>    - Added Reviewed-by tags for patches {1,5}
> 3. Added Tested-by tags from Xianglai Li
> 4. Fixed checkpatch.pl error "Qemu -> QEMU" in [Patch V5 1/9] 
> Link: https://lore.kernel.org/qemu-devel/20231011194355.15628-1-salil.mehta@huawei.com/
> 
> Patch-set  V4 -> V5
> 1. Addressed Gavin Shan's comments
>    - Fixed the trace events print string for kvm_{create,get,park,destroy}_vcpu
>    - Added Reviewed-by tag for patch {1}
> 2. Added Shaoqin Huang's Reviewed-by tags for Patches {2,3}
> 3. Added Tested-by Tag from Vishnu Pajjuri to the patch-set
> 4. Dropped the ARM specific [Patch V4 10/10]
> Link: https://lore.kernel.org/qemu-devel/20231009203601.17584-1-salil.mehta@huawei.com/
> 
> Patch-set  V3 -> 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: https://lore.kernel.org/qemu-devel/20231009112812.10612-1-salil.mehta@huawei.com/
> 
> Patch-set  V2 -> 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 3/10] commit-log with details of ACPI_CPU_SCAN_METHOD macro
>    - Updated [Patch V2 5/10] 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/
> 
> Patch-set V1 -> 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/
> 
> 
> 
> Salil Mehta (8):
>   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: Update ACPI GED framework to support vCPU Hotplug
>   hw/acpi: Update GED _EVT method AML with CPU scan
>   hw/acpi: Update CPUs AML with cpu-(ctrl)dev change
>   physmem: Add helper function to destroy CPU AddressSpace
>   gdbstub: Add helper function to unregister GDB register space
>   docs/specs/acpi_hw_reduced_hotplug: Add the CPU Hotplug Event Bit
> 
>  accel/kvm/kvm-all.c                    | 64 ++++++++++++++++++++------
>  accel/kvm/trace-events                 |  5 +-
>  docs/specs/acpi_hw_reduced_hotplug.rst |  3 +-
>  gdbstub/gdbstub.c                      | 12 +++++
>  hw/acpi/acpi-cpu-hotplug-stub.c        |  6 +++
>  hw/acpi/cpu.c                          | 27 +++++++----
>  hw/acpi/generic_event_device.c         | 21 +++++++++
>  hw/i386/acpi-build.c                   |  3 +-
>  include/exec/cpu-common.h              |  8 ++++
>  include/exec/gdbstub.h                 |  6 +++
>  include/hw/acpi/cpu.h                  |  5 +-
>  include/hw/acpi/cpu_hotplug.h          |  4 ++
>  include/hw/acpi/generic_event_device.h |  4 ++
>  include/hw/core/cpu.h                  |  1 +
>  include/sysemu/kvm.h                   | 16 +++++++
>  system/physmem.c                       | 29 ++++++++++++
>  16 files changed, 185 insertions(+), 29 deletions(-)
> 
> -- 
> 2.34.1