Andrii Nakryiko 86171433b7 libbpf: introduce concept of bpf_link
bpf_link is an abstraction of an association of a BPF program and one of
many possible BPF attachment points (hooks). This allows to have uniform
interface for detaching BPF programs regardless of the nature of link
and how it was created. Details of creation and setting up of a specific
bpf_link is handled by corresponding attachment methods
(bpf_program__attach_xxx) added in subsequent commits. Once successfully
created, bpf_link has to be eventually destroyed with
bpf_link__destroy(), at which point BPF program is disassociated from
a hook and all the relevant resources are freed.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-07-08 12:52:46 -07:00
2019-07-08 12:52:46 -07:00
2019-07-08 12:52:46 -07:00
2019-05-16 09:39:52 -07:00

This is a mirror of bpf-next linux tree's tools/lib/bpf directory plus its supporting header files.

The following files will by sync'ed with bpf-next repo:

  • src/ <-> bpf-next/tools/lib/bpf/
  • include/uapi/linux/bpf_common.h <-> bpf-next/tools/include/uapi/linux/bpf_common.h
  • include/uapi/linux/bpf.h <-> bpf-next/tools/include/uapi/linux/bpf.h
  • include/uapi/linux/btf.h <-> bpf-next/tools/include/uapi/linux/btf.h
  • include/uapi/linux/if_link.h <-> bpf-next/tools/include/uapi/linux/if_link.h
  • include/uapi/linux/if_xdp.h <-> bpf-next/tools/include/uapi/linux/if_xdp.h
  • include/uapi/linux/netlink.h <-> bpf-next/tools/include/uapi/linux/netlink.h
  • include/tools/libc_compat.h <-> bpf-next/tools/include/tools/libc_compat.h

Other header files at this repo (include/linux/*.h) are reduced versions of their counterpart files at bpf-next's tools/include/linux/*.h to make compilation successful.

Build Build Status

libelf is an internal dependency of libbpf and thus it is required to link against and must be installed on the system for applications to work. pkg-config is used by default to find libelf, and the program called can be overridden with PKG_CONFIG. If using pkg-config at build time is not desired, it can be disabled by setting NO_PKG_CONFIG=1 when calling make.

To build both static libbpf.a and shared libbpf.so:

$ cd src
$ make

To build only static libbpf.a library in directory build/ and install them together with libbpf headers in a staging directory root/:

$ cd src
$ mkdir build root
$ BUILD_STATIC_ONLY=y OBJDIR=build DESTDIR=root make install

To build both static libbpf.a and shared libbpf.so against a custom libelf dependency installed in /build/root/ and install them together with libbpf headers in a build directory /build/root/:

$ cd src
$ PKG_CONFIG_PATH=/build/root/lib64/pkgconfig DESTDIR=/build/root make install

To integrate libbpf into a project which uses Meson building system define [wrap-git] file in subprojects folder. To add libbpf dependency to the parent parent project, e.g. for libbpf_static_dep:

libbpf_obj = subproject('libbpf', required : true)
libbpf_static_dep = libbpf_proj.get_variable('libbpf_static_dep')

To validate changes to meson.build

$ python3 meson.py build
$ ninja -C build/

To install headers, libs and pkgconfig

$ cd build
$ ninja install
Description
Automated upstream mirror for libbpf stand-alone build.
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