Re: [PATCH v9 0/8] hw/arm/virt: Introduce cpu topology support

[Richard Henderson <richard.henderson@linaro.org>]

On 10/20/21 7:21 AM, Yanan Wang wrote:
> Hi,
> 
> This is the latest v9 series which supports exposing vCPU topology
> to the guest for Arm virt machines.
> 
> Description of this series:
> Once the view of an accurate virtual cpu topology is provided to guest,
> with a well-designed vCPU pinning to the pCPU we may get a huge benefit,
> e.g., the scheduling performance improvement. See Dario Faggioli's
> research and the related performance tests in [1] for reference.
> 
> This patch series introduces cpu topology support for Arm platform.
> Both cpu-map in DT and ACPI PPTT table are introduced to store the
> topology information. And we only describe the topology information
> to 6.2 and newer virt machines, considering compatibility.
> 
> [1] https://kvmforum2020.sched.com/event/eE1y/virtual-topology-for-virtual-machines
> -friend-or-foe-dario-faggioli-suse

Queued to target-arm.next, thanks.


r~

> 
> Changelog:
> v8->v9:
> - add Eric's R-bs, thanks!
> - address Eric's suggestions to update some function comments and commit msg (patch #5)
> - make build_processor_hierarchy_node static as it's only used by build_pptt (patch #4)
> - retested.
> - v8: https://lore.kernel.org/qemu-devel/20211014132206.19220-1-wangyanan55@huawei.com/
> 
> v7->v8:
> - rebased on top of master (commit e5b2333f24)
> - only add one generic expected file for PPTT instead of four, which works
>    fine enough for now (patch #6 and #8 updated)
> - v7: https://lore.kernel.org/qemu-devel/20211007030746.10420-1-wangyanan55@huawei.com/
> 
> v6->v7:
> - rebased on top of master (commit ca61fa4b80)
> - use newly introduced acpi_table_begin/acpi_table_end APIs to build PPTT
>    (patch #5 updated)
> - add reference files for PPTT to fix broken bios-table-test for Aarch64
>    virt machine (patch #6-#8 added)
> - v6: https://lore.kernel.org/qemu-devel/20210824122016.144364-1-wangyanan55@huawei.com/
> 
> Andrew Jones (2):
>    hw/arm/virt: Add cpu-map to device tree
>    hw/acpi/aml-build: Add PPTT table
> 
> Yanan Wang (6):
>    hw/arm/virt: Only describe cpu topology since virt-6.2
>    device_tree: Add qemu_fdt_add_path
>    hw/acpi/aml-build: Add Processor hierarchy node structure
>    tests/data/acpi/virt: Add an empty expected file for PPTT
>    hw/arm/virt-acpi-build: Generate PPTT table
>    tests/data/acpi/virt: Update the empty expected file for PPTT
> 
>   hw/acpi/aml-build.c          |  89 +++++++++++++++++++++++++++++++++++
>   hw/arm/virt-acpi-build.c     |   8 +++-
>   hw/arm/virt.c                |  71 ++++++++++++++++++++++++----
>   include/hw/acpi/aml-build.h  |   3 ++
>   include/hw/arm/virt.h        |   4 +-
>   include/sysemu/device_tree.h |   1 +
>   softmmu/device_tree.c        |  44 ++++++++++++++++-
>   tests/data/acpi/virt/PPTT    | Bin 0 -> 76 bytes
>   8 files changed, 206 insertions(+), 14 deletions(-)
>   create mode 100644 tests/data/acpi/virt/PPTT
> 
> --
> 2.19.1
>