Re: [dpdk-dev] [PATCH] devtools: select targets in build test

[David Marchand <david.marchand@redhat.com>]

On Thu, Feb 4, 2021 at 2:59 PM Thomas Monjalon <thomas@monjalon.net> wrote:
>
> 04/02/2021 14:34, David Marchand:
> > When a target compilation is broken, one way to skip the target is to
> > uninstall the associated toolchain.
> > But it is not always possible and you end up with hacking the script to
> > avoid this target until a fix is ready.
> >
> > It is also often quicker to check a fix on a failing target before
> > checking compilation on all targets.
> >
> > Introduce a variable to select targets.
> >
> > Example:
> > $ DPDK_BUILD_TEST_TARGETS=build-x86-mingw \
> >     ./devtools/test-meson-builds.sh
>
> With this solution, you need to list all targets you want to compile.

To fill the list, it is easy, with no understand of the script internals:
$ ls $HOME/builds
build-32b              build-arm64-dpaa        build-arm64-octeontx2
build-clang-static  build-gcc-static      build-x86-default
build-arm64-bluefield  build-arm64-host-clang  build-clang-shared
build-gcc-shared    build-ppc64le-power8  build-x86-mingw

>
> An alternative could be to disable a target in the config file
> based on the variable DPDK_TARGET set by load_env.
> One hack, which does not need any change in the script I think,
> is to set targetcc=disabled.
> Or we could check a well defined variable after calling load-devel-config.

A bit fragile since you are bound to this internal shell variable.
Putting logic in ~/.config/dpdk/devel.build is undocumented and more
tedious than passing an environment variable when running the script.


>
> [...]
> > +target_is_selected build-x86-default || exit 0
>
> Why this line?

If the build-x86-default was not compiled in this run because you did
not select it, the call to the install target after this check
triggers a compilation of this target.
This is not wanted from my pov, or at best confusing, because you
don't see anything with the default verbose:

$ DPDK_BUILD_TEST_TARGETS=build-x86-mingw ./devtools/test-meson-builds.sh
ninja: Entering directory `/home/dmarchan/builds/build-x86-mingw'
[...]
Found ninja-1.10.1 at /usr/bin/ninja
[19/19] Linking target examples/dpdk-helloworld.exe

^^ for some time you get no output, you have the impression the script
is stuck, while it is actually compiling the build-x86-default target.

Then,
## Building cmdline
## Building helloworld
## Building l2fwd
## Building l3fwd
## Building multi_process
## Building skeleton
## Building timer

Compiling those examples had nothing to do with the build-x86-mingw
target I was expecting.


-- 
David Marchand