Re: [RFT PATCH v1 0/4] Unify CPU topology across ARM64 & RISC-V

Jeffrey Hugo
2018-12-05T17:53:08Z

On 11/29/2018 4:28 PM, Atish Patra wrote:
> The cpu-map DT entry in ARM64 can describe the CPU topology in
> much better way compared to other existing approaches. RISC-V can
> easily adopt this binding to represent it's own CPU topology.
> Thus, both cpu-map DT binding and topology parsing code can be
> moved to a common location so that RISC-V or any other
> architecture can leverage that.
>
> The relevant discussion regarding unifying cpu topology can be
> found in [1].
>
> arch_topology seems to be a perfect place to move the common
> code. I have not introduced any functional changes in the moved
> code. The only downside in this approach is that the capacity
> code will be executed for RISC-V as well. But, it will exit
> immediately after not able to find the appropriate DT node. If
> the overhead is considered too much, we can always compile out
> capacity related functions under a different config for the
> architectures that do not support them.
>
> The patches have been tested for RISC-V and compile tested for
> ARM64 & x86.
>
> The socket change[2] is also now part of this series.
>
> [1] https://lkml.org/lkml/2018/11/6/19
> [2] https://lkml.org/lkml/2018/11/7/918
>
> QEMU changes for RISC-V topology are available at
>
> https://github.com/atishp04/riscv-qemu/tree/cpu_topo
>
> Apologies for the previous patch series with incorrect title and
> was sent only to kernel mailing list due to a bug in my config.
> Please ignore that.
>
> Atish Patra (3):
> dt-binding: cpu-topology: Move cpu-map to a common binding.
> cpu-topology: Move cpu topology code to common code.
> RISC-V: Parse cpu topology during boot.
>
> Sudeep Holla (1):
> Documentation: DT: arm: add support for sockets defining package
> boundaries
>
> .../{arm/topology.txt => cpu/cpu-topology.txt} | 133 +++++++--
> arch/arm64/include/asm/topology.h | 22 --
> arch/arm64/kernel/topology.c | 303 +--------------------
> arch/riscv/Kconfig | 1 +
> arch/riscv/kernel/smpboot.c | 3 +
> drivers/base/arch_topology.c | 294 ++++++++++++++++++++
> include/linux/arch_topology.h | 26 ++
> include/linux/topology.h | 1 +
> 8 files changed, 435 insertions(+), 348 deletions(-)
> rename Documentation/devicetree/bindings/{arm/topology.txt => cpu/cpu-topology.txt} (66%)
>
> --
> 2.7.4
>

Seems to test fine on QDF2400.

Tested-by: Jeffrey Hugo <jhugo@codeaurora.org>

I did see that git am complained about patch #2 -

patch:103: space before tab in indent.
};
patch:114: space before tab in indent.
};
warning: 2 lines add whitespace errors.

--
Jeffrey Hugo
Qualcomm Datacenter Technologies as an affiliate of Qualcomm
Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the
Code Aurora Forum, a Linux Foundation Collaborative Project.