bc1a85977b
BPF tail call uses the BPF_MAP_TYPE_PROG_ARRAY type map for calling
into other BPF programs and this PROG_ARRAY should be filled prior to
use. Currently, samples with the PROG_ARRAY type MAP fill this program
array with bpf_load. For bpf_load to fill this map, kernel BPF program
must specify the section with specific format of <prog_type>/<array_idx>
(e.g. SEC("socket/0"))
But by using libbpf instead of bpf_load, user program can specify which
programs should be added to PROG_ARRAY. The advantage of this approach
is that you can selectively add only the programs you want, rather than
adding all of them to PROG_ARRAY, and it's much more intuitive than the
traditional approach.
This commit refactors user programs with the PROG_ARRAY type MAP with
libbpf instead of using bpf_load.
Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200516040608.1377876-4-danieltimlee@gmail.com
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.