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In-Reply-To: <20230407181105.GC1018455@dev-arch.thelio-3990X>
From:   Masahiro Yamada <masahiroy@kernel.org>
Date:   Sat, 8 Apr 2023 10:32:23 +0900
Message-ID: <CAK7LNATnmZRXH5E+oPfsDyf=YhUKPBVHG01bosUbtqEDSy+3tQ@mail.gmail.com>
Subject: Re: [PATCH 2/3] kbuild: do not create intermediate *.tar for source tarballs
To:     Nathan Chancellor <nathan@kernel.org>
Cc:     linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org,
        Nick Desaulniers <ndesaulniers@google.com>,
        Nicolas Schier <nicolas@fjasle.eu>
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On Sat, Apr 8, 2023 at 3:11=E2=80=AFAM Nathan Chancellor <nathan@kernel.org=
> wrote:
>
> On Fri, Apr 07, 2023 at 07:16:28PM +0900, Masahiro Yamada wrote:
> > Since commit 05e96e96a315 ("kbuild: use git-archive for source package
> > creation"), source tarballs are created in two steps; create *.tar file
> > then compress it. I split the compression as a separate rule because I
> > just thought 'git archive' supported only gzip for compression. I admit
> > the unneeded *.tar file is annoying.
> >
> > For other compression algorithms, I could pipe the two commands:
> >
> >   $ git archive HEAD | xz > linux.tar.xz
> >
> > I read git-archive(1) carefully, and I realized GIT had provided a
> > more elegant way:
>
> Hooray for documentation :)
>
> >   $ git -c tar.tar.xz.command=3Dxz archive -o linux.tar.xz HEAD
> >
> > This commit uses 'tar.tar.*.command' configuration to specify the
> > compression backend so we can create a compressed tarball directly.
> >
> > GIT commit 767cf4579f0e ("archive: implement configurable tar filters")
> > is more than a decade old, so it should be available on almost all buil=
d
> > environments.
>
> git 1.7.7 it seems, certainly ancientware in my opinion. If people have
> issues with this, they can just upgrade git; even RHEL7 has git 1.8.x.
>
> > Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
>
> Reviewed-by: Nathan Chancellor <nathan@kernel.org>
>
> > ---
> >
> >  scripts/Makefile.package | 24 +++++++++++++++++-------
> >  1 file changed, 17 insertions(+), 7 deletions(-)
> >
> > diff --git a/scripts/Makefile.package b/scripts/Makefile.package
> > index a205617730c6..7707975f729b 100644
> > --- a/scripts/Makefile.package
> > +++ b/scripts/Makefile.package
> > @@ -57,16 +57,23 @@ check-git:
> >               false; \
> >       fi
> >
> > +archive-config-tar.gz  =3D -c tar.tar.gz.command=3D"$(KGZIP)"
> > +archive-config-tar.bz2 =3D -c tar.tar.bz2.command=3D"$(KBZIP2)"
> > +archive-config-tar.xz  =3D -c tar.tar.xz.command=3D"$(XZ)"
> > +archive-config-tar.zst =3D -c tar.tar.zst.command=3D"$(ZSTD)"
> > +
> >  quiet_cmd_archive =3D ARCHIVE $@
> > -      cmd_archive =3D git -C $(srctree) archive \
> > +      cmd_archive =3D git -C $(srctree) $(archive-config-tar$(suffix $=
@)) archive \
> >                      --output=3D$$(realpath $@) --prefix=3D$(basename $=
@)/ $(archive-args)
> >
> >  # Linux source tarball
> >  # --------------------------------------------------------------------=
-------
> >
> > -targets +=3D linux.tar
> > -linux.tar: archive-args =3D $$(cat $<)
> > -linux.tar: .tmp_HEAD FORCE
> > +linux-tarballs :=3D $(addprefix linux, .tar.gz)
>
> Is there any reason not to allow other compression formats for linux
> like you do for perf?


Currently, gzip is only allowed because there is no way to specify
the compression algorithm.
I already have a patch locally, but not submitted yet.

I prioritize groundwork, then add new features later.


--=20
Best Regards
Masahiro Yamada