Re: [PATCH 1/3] kbuild: avoid concurrency issue in parallel building dtbs and dtbs_check

[Rob Herring]

On Tue, Mar 3, 2020 at 9:20 PM Masahiro Yamada <masahiroy@xxxxxxxxxx> wrote:
>
> 'make dtbs_check' checks the shecma in addition to building *.dtb files,

typo

> in other words, 'make dtbs_check' is a super-set of 'make dtbs'.
> So, you do not have to do 'make dtbs dtbs_check', but I want to keep
> the build system robust in any use.
>
> Currently, 'dtbs' and 'dtbs_check' are independent of each other.
> In parallel building, two threads descend into arch/*/boot/dts/,
> one for dtbs and the other for dtbs_check, then end up with building
> the same DTB simultaneously.
>
> This commit fixes the concurrency issue. Otherwise, I see build errors
> like follows:
>
> $ make ARCH=arm64 defconfig
> $ make -j16 ARCH=arm64 DT_SCHEMA_FILES=Documentation/devicetree/bindings/arm/psci.yaml dtbs dtbs_check
>   <snip>
>   DTC     arch/arm64/boot/dts/qcom/sdm845-cheza-r2.dtb
>   DTC     arch/arm64/boot/dts/amlogic/meson-gxl-s905x-p212.dtb
>   DTC     arch/arm64/boot/dts/allwinner/sun50i-h6-orangepi-lite2.dtb
>   DTC     arch/arm64/boot/dts/allwinner/sun50i-h6-orangepi-lite2.dtb
>   DTC     arch/arm64/boot/dts/freescale/imx8mn-evk.dtb
>   DTC     arch/arm64/boot/dts/allwinner/sun50i-h6-orangepi-one-plus.dtb
>   DTC     arch/arm64/boot/dts/zte/zx296718-pcbox.dtb
>   DTC     arch/arm64/boot/dts/altera/socfpga_stratix10_socdk.dt.yaml
>   DTC     arch/arm64/boot/dts/amlogic/meson-gxl-s905d-p230.dtb
>   DTC     arch/arm64/boot/dts/xilinx/zynqmp-zc1254-revA.dtb
>   DTC     arch/arm64/boot/dts/allwinner/sun50i-h6-pine-h64.dtb
>   DTC     arch/arm64/boot/dts/rockchip/rk3399-gru-scarlet-inx.dtb
>   DTC     arch/arm64/boot/dts/allwinner/sun50i-h6-orangepi-one-plus.dtb
>   CHECK   arch/arm64/boot/dts/altera/socfpga_stratix10_socdk.dt.yaml
> fixdep: error opening file: arch/arm64/boot/dts/allwinner/.sun50i-h6-orangepi-lite2.dtb.d: No such file or directory
> make[2]: *** [scripts/Makefile.lib:296: arch/arm64/boot/dts/allwinner/sun50i-h6-orangepi-lite2.dtb] Error 2
> make[2]: *** Deleting file 'arch/arm64/boot/dts/allwinner/sun50i-h6-orangepi-lite2.dtb'
> make[2]: *** Waiting for unfinished jobs....
>   DTC     arch/arm64/boot/dts/rockchip/rk3399-gru-scarlet-kd.dtb
>   DTC     arch/arm64/boot/dts/amlogic/meson-gxl-s905d-p231.dtb
>   DTC     arch/arm64/boot/dts/xilinx/zynqmp-zc1275-revA.dtb
>   DTC     arch/arm64/boot/dts/freescale/imx8mn-ddr4-evk.dtb
> fixdep: parse error; no targets found
> make[2]: *** [scripts/Makefile.lib:296: arch/arm64/boot/dts/allwinner/sun50i-h6-orangepi-one-plus.dtb] Error 1
> make[2]: *** Deleting file 'arch/arm64/boot/dts/allwinner/sun50i-h6-orangepi-one-plus.dtb'
> make[1]: *** [scripts/Makefile.build:505: arch/arm64/boot/dts/allwinner] Error 2
> make[1]: *** Waiting for unfinished jobs....
>   DTC     arch/arm64/boot/dts/renesas/r8a77951-salvator-xs.dtb
>
> Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
> ---
>
>  Makefile | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)

Reviewed-by: Rob Herring <robh@xxxxxxxxxx>