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

Atish Patra
2018-12-11T00:26:52Z

On 12/5/18 9:53 AM, Jeffrey Hugo wrote:
> 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>
>

Thanks for verifying the patches.

> 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.
>
>

Thanks for pointing it out. For some reason, cherry-pick did not
complain about these. I will fix them.

Regards,
Atish