tools: bpftool: add documentation for net attach/detach

Since, new sub-command 'net attach/detach' has been added for
attaching XDP program on interface,
this commit documents usage and sample output of `net attach/detach`.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
Daniel T. Lee 2019-08-13 11:46:21 +09:00 committed by Alexei Starovoitov
parent 10a708c24a
commit cb9d996866

View file

@ -15,17 +15,22 @@ SYNOPSIS
*OPTIONS* := { [{ **-j** | **--json** }] [{ **-p** | **--pretty** }] }
*COMMANDS* :=
{ **show** | **list** } [ **dev** name ] | **help**
{ **show** | **list** | **attach** | **detach** | **help** }
NET COMMANDS
============
| **bpftool** **net { show | list } [ dev name ]**
| **bpftool** **net { show | list }** [ **dev** *NAME* ]
| **bpftool** **net attach** *ATTACH_TYPE* *PROG* **dev** *NAME* [ **overwrite** ]
| **bpftool** **net detach** *ATTACH_TYPE* **dev** *NAME*
| **bpftool** **net help**
|
| *PROG* := { **id** *PROG_ID* | **pinned** *FILE* | **tag** *PROG_TAG* }
| *ATTACH_TYPE* := { **xdp** | **xdpgeneric** | **xdpdrv** | **xdpoffload** }
DESCRIPTION
===========
**bpftool net { show | list } [ dev name ]**
**bpftool net { show | list }** [ **dev** *NAME* ]
List bpf program attachments in the kernel networking subsystem.
Currently, only device driver xdp attachments and tc filter
@ -47,6 +52,24 @@ DESCRIPTION
all bpf programs attached to non clsact qdiscs, and finally all
bpf programs attached to root and clsact qdisc.
**bpftool** **net attach** *ATTACH_TYPE* *PROG* **dev** *NAME* [ **overwrite** ]
Attach bpf program *PROG* to network interface *NAME* with
type specified by *ATTACH_TYPE*. Previously attached bpf program
can be replaced by the command used with **overwrite** option.
Currently, only XDP-related modes are supported for *ATTACH_TYPE*.
*ATTACH_TYPE* can be of:
**xdp** - try native XDP and fallback to generic XDP if NIC driver does not support it;
**xdpgeneric** - Generic XDP. runs at generic XDP hook when packet already enters receive path as skb;
**xdpdrv** - Native XDP. runs earliest point in driver's receive path;
**xdpoffload** - Offload XDP. runs directly on NIC on each packet reception;
**bpftool** **net detach** *ATTACH_TYPE* **dev** *NAME*
Detach bpf program attached to network interface *NAME* with
type specified by *ATTACH_TYPE*. To detach bpf program, same
*ATTACH_TYPE* previously used for attach must be specified.
Currently, only XDP-related modes are supported for *ATTACH_TYPE*.
**bpftool net help**
Print short help message.
@ -137,6 +160,34 @@ EXAMPLES
}
]
|
| **# bpftool net attach xdpdrv id 16 dev enp6s0np0**
| **# bpftool net**
::
xdp:
enp6s0np0(4) driver id 16
|
| **# bpftool net attach xdpdrv id 16 dev enp6s0np0**
| **# bpftool net attach xdpdrv id 20 dev enp6s0np0 overwrite**
| **# bpftool net**
::
xdp:
enp6s0np0(4) driver id 20
|
| **# bpftool net attach xdpdrv id 16 dev enp6s0np0**
| **# bpftool net detach xdpdrv dev enp6s0np0**
| **# bpftool net**
::
xdp:
SEE ALSO
========