v4.19.13 snapshot.
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+================
+bpftool-cgroup
+================
+-------------------------------------------------------------------------------
+tool for inspection and simple manipulation of eBPF progs
+-------------------------------------------------------------------------------
+
+:Manual section: 8
+
+SYNOPSIS
+========
+
+ **bpftool** [*OPTIONS*] **cgroup** *COMMAND*
+
+ *OPTIONS* := { { **-j** | **--json** } [{ **-p** | **--pretty** }] | { **-f** | **--bpffs** } }
+
+ *COMMANDS* :=
+ { **show** | **list** | **tree** | **attach** | **detach** | **help** }
+
+MAP COMMANDS
+=============
+
+| **bpftool** **cgroup { show | list }** *CGROUP*
+| **bpftool** **cgroup tree** [*CGROUP_ROOT*]
+| **bpftool** **cgroup attach** *CGROUP* *ATTACH_TYPE* *PROG* [*ATTACH_FLAGS*]
+| **bpftool** **cgroup detach** *CGROUP* *ATTACH_TYPE* *PROG*
+| **bpftool** **cgroup help**
+|
+| *PROG* := { **id** *PROG_ID* | **pinned** *FILE* | **tag** *PROG_TAG* }
+| *ATTACH_TYPE* := { **ingress** | **egress** | **sock_create** | **sock_ops** | **device** |
+| **bind4** | **bind6** | **post_bind4** | **post_bind6** | **connect4** | **connect6** |
+| **sendmsg4** | **sendmsg6** }
+| *ATTACH_FLAGS* := { **multi** | **override** }
+
+DESCRIPTION
+===========
+ **bpftool cgroup { show | list }** *CGROUP*
+ List all programs attached to the cgroup *CGROUP*.
+
+ Output will start with program ID followed by attach type,
+ attach flags and program name.
+
+ **bpftool cgroup tree** [*CGROUP_ROOT*]
+ Iterate over all cgroups in *CGROUP_ROOT* and list all
+ attached programs. If *CGROUP_ROOT* is not specified,
+ bpftool uses cgroup v2 mountpoint.
+
+ The output is similar to the output of cgroup show/list
+ commands: it starts with absolute cgroup path, followed by
+ program ID, attach type, attach flags and program name.
+
+ **bpftool cgroup attach** *CGROUP* *ATTACH_TYPE* *PROG* [*ATTACH_FLAGS*]
+ Attach program *PROG* to the cgroup *CGROUP* with attach type
+ *ATTACH_TYPE* and optional *ATTACH_FLAGS*.
+
+ *ATTACH_FLAGS* can be one of: **override** if a sub-cgroup installs
+ some bpf program, the program in this cgroup yields to sub-cgroup
+ program; **multi** if a sub-cgroup installs some bpf program,
+ that cgroup program gets run in addition to the program in this
+ cgroup.
+
+ Only one program is allowed to be attached to a cgroup with
+ no attach flags or the **override** flag. Attaching another
+ program will release old program and attach the new one.
+
+ Multiple programs are allowed to be attached to a cgroup with
+ **multi**. They are executed in FIFO order (those that were
+ attached first, run first).
+
+ Non-default *ATTACH_FLAGS* are supported by kernel version 4.14
+ and later.
+
+ *ATTACH_TYPE* can be on of:
+ **ingress** ingress path of the inet socket (since 4.10);
+ **egress** egress path of the inet socket (since 4.10);
+ **sock_create** opening of an inet socket (since 4.10);
+ **sock_ops** various socket operations (since 4.12);
+ **device** device access (since 4.15);
+ **bind4** call to bind(2) for an inet4 socket (since 4.17);
+ **bind6** call to bind(2) for an inet6 socket (since 4.17);
+ **post_bind4** return from bind(2) for an inet4 socket (since 4.17);
+ **post_bind6** return from bind(2) for an inet6 socket (since 4.17);
+ **connect4** call to connect(2) for an inet4 socket (since 4.17);
+ **connect6** call to connect(2) for an inet6 socket (since 4.17);
+ **sendmsg4** call to sendto(2), sendmsg(2), sendmmsg(2) for an
+ unconnected udp4 socket (since 4.18);
+ **sendmsg6** call to sendto(2), sendmsg(2), sendmmsg(2) for an
+ unconnected udp6 socket (since 4.18).
+
+ **bpftool cgroup detach** *CGROUP* *ATTACH_TYPE* *PROG*
+ Detach *PROG* from the cgroup *CGROUP* and attach type
+ *ATTACH_TYPE*.
+
+ **bpftool prog 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**.
+
+ -f, --bpffs
+ Show file names of pinned programs.
+
+EXAMPLES
+========
+|
+| **# mount -t bpf none /sys/fs/bpf/**
+| **# mkdir /sys/fs/cgroup/test.slice**
+| **# bpftool prog load ./device_cgroup.o /sys/fs/bpf/prog**
+| **# bpftool cgroup attach /sys/fs/cgroup/test.slice/ device id 1 allow_multi**
+
+**# bpftool cgroup list /sys/fs/cgroup/test.slice/**
+
+::
+
+ ID AttachType AttachFlags Name
+ 1 device allow_multi bpf_prog1
+
+|
+| **# bpftool cgroup detach /sys/fs/cgroup/test.slice/ device id 1**
+| **# bpftool cgroup list /sys/fs/cgroup/test.slice/**
+
+::
+
+ ID AttachType AttachFlags Name
+
+SEE ALSO
+========
+ **bpftool**\ (8), **bpftool-prog**\ (8), **bpftool-map**\ (8)