18841da981
The "SEE ALSO" sections of bpftool's manual pages refer to bpf(2), bpf-helpers(7), then all existing bpftool man pages (save the current one). This leads to nearly-identical lists being duplicated in all manual pages. Ideally, when a new page is created, all lists should be updated accordingly, but this has led to omissions and inconsistencies multiple times in the past. Let's take it out of the RST files and generate the "SEE ALSO" sections automatically in the Makefile when generating the man pages. The lists are not really useful in the RST anyway because all other pages are available in the same directory. v3: - Fix conflict with a previous patchset that introduced RST2MAN_OPTS variable passed to rst2man. v2: - Use "echo -n" instead of "printf" in Makefile, to avoid any risk of passing a format string directly to the command. Signed-off-by: Quentin Monnet <quentin@isovalent.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200910203935.25304-1-quentin@isovalent.com
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2.7 KiB
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109 lines
2.7 KiB
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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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SYNOPSIS
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========
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**bpftool** [*OPTIONS*] **link** *COMMAND*
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*OPTIONS* := { { **-j** | **--json** } [{ **-p** | **--pretty** }] | { **-f** | **--bpffs** } }
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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
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specified show information only about given link,
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otherwise list all links currently active on the system.
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Output will start with link ID followed by link type and
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zero or more named attributes, some of which depend on type
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of link.
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Since Linux 5.8 bpftool is able to discover information about
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processes that hold open file descriptors (FDs) against BPF
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links. On such kernels bpftool will automatically emit this
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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
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contain a dot character ('.'), which is reserved for future
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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
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program will stay valid, but they will be detached from the
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respective BPF hook and BPF link will transition into
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a defunct state until last open file descriptor for that
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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
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links.
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-n, --nomount
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Do not automatically attempt to mount any virtual file system
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(such as 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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