diff options
Diffstat (limited to 'tools/bpf/bpftool/Documentation/bpftool-link.rst')
| -rw-r--r-- | tools/bpf/bpftool/Documentation/bpftool-link.rst | 61 |
1 files changed, 26 insertions, 35 deletions
diff --git a/tools/bpf/bpftool/Documentation/bpftool-link.rst b/tools/bpf/bpftool/Documentation/bpftool-link.rst index 0e43d7b06c11..52a4eee4af54 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-link.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-link.rst @@ -1,3 +1,5 @@ +.. SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) + ================ bpftool-link ================ @@ -7,12 +9,14 @@ tool for inspection and simple manipulation of eBPF links :Manual section: 8 +.. include:: substitutions.rst + SYNOPSIS ======== **bpftool** [*OPTIONS*] **link** *COMMAND* - *OPTIONS* := { { **-j** | **--json** } [{ **-p** | **--pretty** }] | { **-f** | **--bpffs** } } + *OPTIONS* := { |COMMON_OPTIONS| | { **-f** | **--bpffs** } | { **-n** | **--nomount** } } *COMMANDS* := { **show** | **list** | **pin** | **help** } @@ -21,6 +25,7 @@ LINK COMMANDS | **bpftool** **link { show | list }** [*LINK*] | **bpftool** **link pin** *LINK* *FILE* +| **bpftool** **link detach** *LINK* | **bpftool** **link help** | | *LINK* := { **id** *LINK_ID* | **pinned** *FILE* } @@ -37,6 +42,11 @@ DESCRIPTION zero or more named attributes, some of which depend on type of link. + Since Linux 5.8 bpftool is able to discover information about + processes that hold open file descriptors (FDs) against BPF + links. On such kernels bpftool will automatically emit this + information as well. + **bpftool link pin** *LINK* *FILE* Pin link *LINK* as *FILE*. @@ -44,23 +54,19 @@ DESCRIPTION contain a dot character ('.'), which is reserved for future extensions of *bpffs*. + **bpftool link detach** *LINK* + Force-detach link *LINK*. BPF link and its underlying BPF + program will stay valid, but they will be detached from the + respective BPF hook and BPF link will transition into + a defunct state until last open file descriptor for that + link is closed. + **bpftool link help** Print short help message. OPTIONS ======= - -h, --help - Print short generic help message (similar to **bpftool help**). - - -V, --version - Print version number (similar to **bpftool version**). - - -j, --json - Generate JSON output. For commands that cannot produce JSON, this - option has no effect. - - -p, --pretty - Generate human-readable JSON output. Implies **-j**. + .. include:: common_options.rst -f, --bpffs When showing BPF links, show file names of pinned @@ -70,10 +76,6 @@ OPTIONS Do not automatically attempt to mount any virtual file system (such as tracefs or BPF virtual file system) when necessary. - -d, --debug - Print all logs available, even debug-level information. This - includes logs from libbpf. - EXAMPLES ======== **# bpftool link show** @@ -82,6 +84,7 @@ EXAMPLES 10: cgroup prog 25 cgroup_id 614 attach_type egress + pids test_progs(223) **# bpftool --json --pretty link show** @@ -91,7 +94,12 @@ EXAMPLES "type": "cgroup", "prog_id": 25, "cgroup_id": 614, - "attach_type": "egress" + "attach_type": "egress", + "pids": [{ + "pid": 223, + "comm": "test_progs" + } + ] } ] @@ -102,20 +110,3 @@ EXAMPLES :: -rw------- 1 root root 0 Apr 23 21:39 link - - -SEE ALSO -======== - **bpf**\ (2), - **bpf-helpers**\ (7), - **bpftool**\ (8), - **bpftool-btf**\ (8), - **bpftool-cgroup**\ (8), - **bpftool-feature**\ (8), - **bpftool-gen**\ (8), - **bpftool-iter**\ (8), - **bpftool-map**\ (8), - **bpftool-net**\ (8), - **bpftool-perf**\ (8), - **bpftool-prog**\ (8), - **bpftool-struct_ops**\ (8) |