Re: [PATCH 0/6] Introduce acpi_table_parse_cedt and extra nodes for CXL.mem

[Jonathan Cameron <Jonathan.Cameron@Huawei.com>]

On Fri, 29 Oct 2021 12:51:27 -0700
Dan Williams <dan.j.williams@intel.com> wrote:

> Hi Rafael,
> 
> While reviewing "[PATCH v3] ACPI: NUMA: Add a node and memblk for each
> CFMWS not in SRAT" [1]. I noticed that it was open coding CEDT sub-table
> parsing in a similar fashion as drivers/cxl/acpi.c. The driver open
> coded the parsing because the ACPI sub-table helpers are marked __init.
> In order to avoid the ongoing maintenance burden of a split between
> "early" and "late" ACPI sub-table parsing this series proposes to make
> those helpers available to drivers.
> 
> The savings in drivers/cxl/ are:
> 
>  drivers/cxl/Kconfig |    1 
>  drivers/cxl/acpi.c  |  234 +++++++++++++++++++--------------------------------
>  2 files changed, 88 insertions(+), 147 deletions(-)
> 
> ...and 15 lines new code not added are saved in this new version of
> "ACPI: NUMA: Add a node and memblk for each CFMWS not in SRAT".
> 
> Let me know if this looks ok to you and I can carry it in the CXL tree
> (i.e. after the merge window, for v5.17 consideration).
> 
> [1]: https://lore.kernel.org/r/20211019050908.449231-1-alison.schofield@intel.com

Is it worth the complexity of the __init_or_acpilib and export part?
Seems like a fiddly dance for what looks to be minor savings...

Jonathan

> 
> ---
> 
> Alison Schofield (1):
>       ACPI: NUMA: Add a node and memblk for each CFMWS not in SRAT
> 
> Dan Williams (5):
>       ACPI: Keep sub-table parsing infrastructure available for modules
>       ACPI: Teach ACPI table parsing about the CEDT header format
>       ACPI: Add a context argument for table parsing handlers
>       cxl/acpi: Convert CFMWS parsing to ACPI sub-table helpers
>       cxl/test: Mock acpi_table_parse_cedt()
> 
> 
>  drivers/acpi/Kconfig          |    3 +
>  drivers/acpi/numa/srat.c      |   59 ++++++++++
>  drivers/acpi/tables.c         |   87 +++++++++++----
>  drivers/cxl/Kconfig           |    1 
>  drivers/cxl/acpi.c            |  237 ++++++++++++++++-------------------------
>  include/linux/acpi.h          |   34 +++++-
>  tools/testing/cxl/Kbuild      |    3 -
>  tools/testing/cxl/test/cxl.c  |   68 ++++++++----
>  tools/testing/cxl/test/mock.c |   30 ++---
>  tools/testing/cxl/test/mock.h |    6 +
>  10 files changed, 304 insertions(+), 224 deletions(-)
> 
> base-commit: c6d7e1341cc99ba49df1384c8c5b3f534a5463b1