pahole starts to use libbpf definitions and APIs since v1.13 after the
commit 21507cd3e97b ("pahole: add libbpf as submodule under lib/bpf").
It works well with the git repository because the libbpf submodule will
use "git submodule update --init --recursive" to update.
Unfortunately, the default github release source code does not contain
libbpf submodule source code and this will cause build issues, the tarball
from https://git.kernel.org/pub/scm/devel/pahole/pahole.git/ is same with
github, you can get the source tarball with corresponding libbpf submodule
codes from
https://fedorapeople.org/~acme/dwarves
This change documents the above issues to give more information so that
we can get the tarball from the right place, early discussion is here:
https://lore.kernel.org/bpf/2de4aad5-fa9e-1c39-3c92-9bb9229d0966@loongson.cn/
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: https://lore.kernel.org/bpf/1619141010-12521-1-git-send-email-yangtiezhu@loongson.cn
The current LLVM and Clang build procedure in samples/bpf/README.rst is
out of date. See below that the links are not accessible any more.
$ git clone http://llvm.org/git/llvm.git
Cloning into 'llvm'...
fatal: unable to access 'http://llvm.org/git/llvm.git/': Maximum (20) redirects followed
$ git clone --depth 1 http://llvm.org/git/clang.git
Cloning into 'clang'...
fatal: unable to access 'http://llvm.org/git/clang.git/': Maximum (20) redirects followed
The LLVM community has adopted new ways to build the compiler. There are
different ways to build LLVM and Clang, the Clang Getting Started page [1]
has one way. As Yonghong said, it is better to copy the build procedure
in Documentation/bpf/bpf_devel_QA.rst to keep consistent.
I verified the procedure and it is proved to be feasible, so we should
update README.rst to reflect the reality. At the same time, update the
related comment in Makefile.
Additionally, as Fangrui said, the dir llvm-project/llvm/build/install is
not used, BUILD_SHARED_LIBS=OFF is the default option [2], so also change
Documentation/bpf/bpf_devel_QA.rst together.
At last, we recommend that developers who want the fastest incremental
builds use the Ninja build system [1], you can find it in your system's
package manager, usually the package is ninja or ninja-build [3], so add
ninja to build dependencies suggested by Nathan.
[1] https://clang.llvm.org/get_started.html
[2] https://www.llvm.org/docs/CMake.html
[3] https://github.com/ninja-build/ninja/wiki/Pre-built-Ninja-packages
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Acked-by: Yonghong Song <yhs@fb.com>
Cc: Fangrui Song <maskray@google.com>
Link: https://lore.kernel.org/bpf/1611279584-26047-1-git-send-email-yangtiezhu@loongson.cn
bpf_devel_QA.rst:152 The subject prefix information is not accurate, it
should be 'PATCH bpf-next v2'
Also update LLVM version info and add information about
‘-DLLVM_TARGETS_TO_BUILD’ to prompt the developer to build the desired
target.
Signed-off-by: Jianlin Lv <Jianlin.Lv@arm.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200821052817.46887-1-Jianlin.Lv@arm.com
Fix the following sphinx warning:
bpf_devel_QA.rst:444: WARNING: Unknown target name:
"documentation/bpf/btf.rst"
No target was defined for 'btf.rst' in the document. Fix it.
Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
Link: https://lore.kernel.org/r/20200718165107.625847-6-dwlsalmeida@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Getting a clean BPF selftests run involves ensuring latest trunk LLVM/clang
are used, pahole is recent (>=1.16) and config matches the specified
config file as closely as possible. Add to bpf_devel_QA.rst and point
tools/testing/selftests/bpf/README.rst to it.
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/1590146674-25485-1-git-send-email-alan.maguire@oracle.com
File 'Documentation/networking/netdev-FAQ.txt' has been converted to RST
format. We should update all links/references to point to the new file.
Update references to netdev-FAQ
Signed-off-by: Tobin C. Harding <me@tobin.cc>
Signed-off-by: David S. Miller <davem@davemloft.net>
I always forget howto run the BPF selftests. Thus, lets add that info
to the QA document.
Documentation was based on Cilium's documentation:
http://cilium.readthedocs.io/en/latest/bpf/#verifying-the-setup
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Same story as bpf_design_QA.rst RST format conversion.
Again thanks to Quentin Monnet <quentin.monnet@netronome.com> for
fixes and patches that have been squashed.
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This will cause them to get auto rendered, e.g. when viewing them on GitHub.
Followup patches will correct the content to be RST compliant.
Also adjust README.rst to point to the renamed files.
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
