ea379b3ccc
As it turns out, the terms in definition lists in the rST file are
already rendered with bold-ish formatting when generating the man pages;
all double-star sequences we have in the commands for the command
description are unnecessary, and can be removed to make the
documentation easier to read.
The rST files were automatically processed with:
sed -i '/DESCRIPTION/,/OPTIONS/ { /^\*/ s/\*\*//g }' b*.rst
Signed-off-by: Rameez Rehman <rameezrehman408@hotmail.com>
Signed-off-by: Quentin Monnet <qmo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20240331200346.29118-3-qmo@kernel.org
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.. SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
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================
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bpftool-link
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================
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-------------------------------------------------------------------------------
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tool for inspection and simple manipulation of eBPF links
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-------------------------------------------------------------------------------
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:Manual section: 8
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.. include:: substitutions.rst
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SYNOPSIS
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========
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**bpftool** [*OPTIONS*] **link** *COMMAND*
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*OPTIONS* := { |COMMON_OPTIONS| | { **-f** | **--bpffs** } | { **-n** | **--nomount** } }
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*COMMANDS* := { **show** | **list** | **pin** | **help** }
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LINK COMMANDS
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=============
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| **bpftool** **link { show | list }** [*LINK*]
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| **bpftool** **link pin** *LINK* *FILE*
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| **bpftool** **link detach** *LINK*
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| **bpftool** **link help**
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| *LINK* := { **id** *LINK_ID* | **pinned** *FILE* }
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DESCRIPTION
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===========
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bpftool link { show | list } [*LINK*]
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Show information about active links. If *LINK* is specified show
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information only about given link, otherwise list all links currently
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active on the system.
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Output will start with link ID followed by link type and zero or more named
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attributes, some of which depend on type of link.
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Since Linux 5.8 bpftool is able to discover information about processes
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that hold open file descriptors (FDs) against BPF links. On such kernels
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bpftool will automatically emit this information as well.
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bpftool link pin *LINK* *FILE*
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Pin link *LINK* as *FILE*.
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Note: *FILE* must be located in *bpffs* mount. It must not contain a dot
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character ('.'), which is reserved for future extensions of *bpffs*.
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bpftool link detach *LINK*
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Force-detach link *LINK*. BPF link and its underlying BPF program will stay
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valid, but they will be detached from the respective BPF hook and BPF link
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will transition into a defunct state until last open file descriptor for
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that link is closed.
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bpftool link help
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Print short help message.
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OPTIONS
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=======
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.. include:: common_options.rst
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-f, --bpffs
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When showing BPF links, show file names of pinned links.
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-n, --nomount
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Do not automatically attempt to mount any virtual file system (such as
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tracefs or BPF virtual file system) when necessary.
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EXAMPLES
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========
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**# bpftool link show**
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::
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10: cgroup prog 25
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cgroup_id 614 attach_type egress
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pids test_progs(223)
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**# bpftool --json --pretty link show**
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::
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[{
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"type": "cgroup",
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"prog_id": 25,
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"cgroup_id": 614,
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"attach_type": "egress",
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"pids": [{
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"pid": 223,
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"comm": "test_progs"
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}
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]
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}
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]
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| **# bpftool link pin id 10 /sys/fs/bpf/link**
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| **# ls -l /sys/fs/bpf/**
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::
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-rw------- 1 root root 0 Apr 23 21:39 link
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