Re: [PATCH] Improved usability of the Makefile in libbpf

From: Andrii Nakryiko
Date: Wed Nov 30 2022 - 19:42:30 EST


On Mon, Nov 28, 2022 at 11:42 PM Xin Liu <liuxin350@xxxxxxxxxx> wrote:
>
> Current libbpf Makefile does not contain the help command, which
> is inconvenient to use. A help command is provided to list the
> commands supported by libbpf make and the functions of the commands.
>
> Signed-off-by: Xin Liu <liuxin350@xxxxxxxxxx>
> ---
> tools/lib/bpf/Makefile | 34 ++++++++++++++++++++++++++++++++++
> 1 file changed, 34 insertions(+)
>
> diff --git a/tools/lib/bpf/Makefile b/tools/lib/bpf/Makefile
> index 4c904ef0b47e..c86e05df4711 100644
> --- a/tools/lib/bpf/Makefile
> +++ b/tools/lib/bpf/Makefile
> @@ -286,3 +286,37 @@ tags:
>
> # Delete partially updated (corrupted) files on error
> .DELETE_ON_ERROR:
> +
> +help:
> + @echo 'Default targets:'
> + @echo ' all - Run all_cmd'
> + @echo ' all_cmd - Build library and pkgconfig, check abi and version info'
> + @echo ''
> + @echo 'Cleaning targets:'
> + @echo ' clean - Remove all generated files'
> + @echo ''
> + @echo 'Build targets:'
> + @echo ' libbpf.so - Build the dynamic library'
> + @echo ' libbpf.a - Build the static library'
> + @echo ' libbpf.pc - Build the pkgconfig file'
> + @echo ''
> + @echo 'Install targets:'
> + @echo ' install - Install all headers, library and pkgconfig file to'
> + @echo ' DESTDIR(default: /) with prefix(default: /usr/local)'
> + @echo ' install_lib - Install only library'
> + @echo ' install_headers - Install only headers'
> + @echo ' install_pkgconfig - Install only pkgconfig file'
> + @echo ''
> + @echo 'Other generic targets:'
> + @echo ' cscope - Generate cscope index'
> + @echo ' tags - Generate tags file for editors'
> + @echo ' check - Check abi and version info'
> + @echo ' check_abi - Check versioned symbols'
> + @echo ' check_version - Check whether the libbpf version defined in libbpf_version.h'
> + @echo ' is the same as that defined in libbpf.map'
> + @echo ''
> + @echo ' make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
> + @echo ' make DESTDIR=/root [install targets] use DESTDIR for installing'
> + @echo ' into a different root directory'
> + @echo ' make prefix=/path [install targets] use prefix for installing'
> + @echo ' into a user defined prefix path'


I'm a bit hesitant about adding all this. Most of those targets are
not intended to be used directly, only "all", "clean", and "install"
are supposed to be used by end-users (maybe also "install_headers").
And those seems to be pretty typical and straightforward targets.

I actually didn't even know about `make help`, but I checked perf's
`make help` and it's way more succinct, let's try modeling it here?

Also, please use [PATCH bpf-next] (with v2 in between them) for next
submission to point that this is meant for bpf-next tree.


> --
> 2.33.0
>