Re: [PATCH] [RFC] dt-bindings: Consider DT_SCHEMA_FILES when finding all json-schema

[Rob Herring <robh+dt@kernel.org>]

On Tue, Mar 9, 2021 at 4:21 AM Geert Uytterhoeven
<geert+renesas@glider.be> wrote:
>
> Setting DT_SCHEMA_FILES allows the user to restrict the
> "dt_binding_check" make target to a specified set of DT binding files.
> However, yamllint is still run on all available files, which can take
> quite some time.
>
> Fix this by changing "find_cmd" to only return the specified files.
> Note that this also affects the "cmd_chk_bindings" and "cmd_mk_schema"
> rules.
>
> This reduces the execution time of
>
>     make dt_binding_check DT_SCHEMA_FILES=/path/to/json/schema/file
>
> from ca. 22 to less than 2 seconds on an i7-8700K.

We could use xargs sharding like 'chk_bindings' does. That goes from
18s to 5s for me (i7-7700HQ). Good enough? Not sure why I didn't other
than thinking 20sec was fast enough.

Another option would be doing yamllint as part of cmd_extract_ex or we
could have a command line variable to disable yamllint.

> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> ---
> Should this be restricted to cmd_yamllint?
> I'm not sure which users of find_cmd do and do not need all files.

cmd_chk_bindings always does. cmd_mk_schema needs both. So I think
this doesn't work for all cases.

> ---
>  Documentation/devicetree/bindings/Makefile | 8 ++++++++
>  1 file changed, 8 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/Makefile b/Documentation/devicetree/bindings/Makefile
> index 780e5618ec0ae2fc..60ac03bade2da0ad 100644
> --- a/Documentation/devicetree/bindings/Makefile
> +++ b/Documentation/devicetree/bindings/Makefile
> @@ -22,10 +22,18 @@ $(obj)/%.example.dts: $(src)/%.yaml check_dtschema_version FORCE
>  # Use full schemas when checking %.example.dts
>  DT_TMP_SCHEMA := $(obj)/processed-schema-examples.json
>
> +ifeq ($(DT_SCHEMA_FILES),)
> +
>  find_cmd = find $(srctree)/$(src) \( -name '*.yaml' ! \
>                 -name 'processed-schema*' ! \
>                 -name '*.example.dt.yaml' \)
>
> +else
> +
> +find_cmd = echo $(addprefix $(srctree)/, $(DT_SCHEMA_FILES))
> +
> +endif
> +
>  quiet_cmd_yamllint = LINT    $(src)
>        cmd_yamllint = ($(find_cmd) | \
>                       xargs $(DT_SCHEMA_LINT) -f parsable -c $(srctree)/$(src)/.yamllint) || true
> --
> 2.25.1
>