Andrii Nakryiko fe1ce6bd74 libbpf: auto-set PERF_EVENT_ARRAY size to number of CPUs
For BPF_MAP_TYPE_PERF_EVENT_ARRAY typically correct size is number of
possible CPUs. This is impossible to specify at compilation time. This
change adds automatic setting of PERF_EVENT_ARRAY size to number of
system CPUs, unless non-zero size is specified explicitly. This allows
to adjust size for advanced specific cases, while providing convenient
and logical defaults.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Yonghong Song <yhs@fb.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
2019-05-16 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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