This patch series adds various observability APIs to bpf_link:
- each bpf_link now gets ID, similar to bpf_map and bpf_prog, by which
user-space can iterate over all existing bpf_links and create limited FD
from ID;
- allows to get extra object information with bpf_link general and
type-specific information;
- implements `bpf link show` command which lists all active bpf_links in the
system;
- implements `bpf link pin` allowing to pin bpf_link by ID or from other
pinned path.
v2->v3:
- improve spin locking around bpf_link ID (Alexei);
- simplify bpf_link_info handling and fix compilation error on sh arch;
v1->v2:
- simplified `bpftool link show` implementation (Quentin);
- fixed formatting of bpftool-link.rst (Quentin);
- fixed attach type printing logic (Quentin);
rfc->v1:
- dropped read-only bpf_links (Alexei);
- fixed bug in bpf_link_cleanup() not removing ID;
- fixed bpftool link pinning search logic;
- added bash-completion and man page.
Andrii Nakryiko (10):
bpf: refactor bpf_link update handling
bpf: allocate ID for bpf_link
bpf: support GET_FD_BY_ID and GET_NEXT_ID for bpf_link
bpf: add support for BPF_OBJ_GET_INFO_BY_FD for bpf_link
libbpf: add low-level APIs for new bpf_link commands
selftests/bpf: test bpf_link's get_next_id, get_fd_by_id, and
get_obj_info
bpftool: expose attach_type-to-string array to non-cgroup code
bpftool: add bpf_link show and pin support
bpftool: add bpftool-link manpage
bpftool: add link bash completions
include/linux/bpf-cgroup.h | 14 -
include/linux/bpf.h | 26 +-
include/linux/bpf_types.h | 6 +
include/uapi/linux/bpf.h | 31 ++
kernel/bpf/btf.c | 2 +
kernel/bpf/cgroup.c | 87 ++++-
kernel/bpf/syscall.c | 354 ++++++++++++++----
kernel/bpf/verifier.c | 2 +
kernel/cgroup/cgroup.c | 27 --
.../bpftool/Documentation/bpftool-link.rst | 118 ++++++
tools/bpf/bpftool/bash-completion/bpftool | 39 ++
tools/bpf/bpftool/cgroup.c | 48 +--
tools/bpf/bpftool/common.c | 2 +
tools/bpf/bpftool/link.c | 333 ++++++++++++++++
tools/bpf/bpftool/main.c | 6 +-
tools/bpf/bpftool/main.h | 37 ++
tools/include/uapi/linux/bpf.h | 31 ++
tools/lib/bpf/bpf.c | 19 +-
tools/lib/bpf/bpf.h | 4 +-
tools/lib/bpf/libbpf.map | 6 +
.../selftests/bpf/prog_tests/bpf_obj_id.c | 110 +++++-
.../testing/selftests/bpf/progs/test_obj_id.c | 14 +-
22 files changed, 1132 insertions(+), 184 deletions(-)
create mode 100644 tools/bpf/bpftool/Documentation/bpftool-link.rst
create mode 100644 tools/bpf/bpftool/link.c
--
2.24.1
