tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1===============
2bpftool-feature
3===============
4-------------------------------------------------------------------------------
5tool for inspection of eBPF-related parameters for Linux kernel or net device
6-------------------------------------------------------------------------------
7
8:Manual section: 8
9
10SYNOPSIS
11========
12
13 **bpftool** [*OPTIONS*] **feature** *COMMAND*
14
15 *OPTIONS* := { { **-j** | **--json** } [{ **-p** | **--pretty** }] }
16
17 *COMMANDS* := { **probe** | **help** }
18
19FEATURE COMMANDS
20================
21
22| **bpftool** **feature probe** [*COMPONENT*] [**full**] [**macros** [**prefix** *PREFIX*]]
23| **bpftool** **feature help**
24|
25| *COMPONENT* := { **kernel** | **dev** *NAME* }
26
27DESCRIPTION
28===========
29 **bpftool feature probe** [**kernel**] [**full**] [**macros** [**prefix** *PREFIX*]]
30 Probe the running kernel and dump a number of eBPF-related
31 parameters, such as availability of the **bpf()** system call,
32 JIT status, eBPF program types availability, eBPF helper
33 functions availability, and more.
34
35 By default, bpftool **does not run probes** for
36 **bpf_probe_write_user**\ () and **bpf_trace_printk**\()
37 helpers which print warnings to kernel logs. To enable them
38 and run all probes, the **full** keyword should be used.
39
40 If the **macros** keyword (but not the **-j** option) is
41 passed, a subset of the output is dumped as a list of
42 **#define** macros that are ready to be included in a C
43 header file, for example. If, additionally, **prefix** is
44 used to define a *PREFIX*, the provided string will be used
45 as a prefix to the names of the macros: this can be used to
46 avoid conflicts on macro names when including the output of
47 this command as a header file.
48
49 Keyword **kernel** can be omitted. If no probe target is
50 specified, probing the kernel is the default behaviour.
51
52 **bpftool feature probe dev** *NAME* [**full**] [**macros** [**prefix** *PREFIX*]]
53 Probe network device for supported eBPF features and dump
54 results to the console.
55
56 The keywords **full**, **macros** and **prefix** have the
57 same role as when probing the kernel.
58
59 **bpftool feature help**
60 Print short help message.
61
62OPTIONS
63=======
64 -h, --help
65 Print short generic help message (similar to **bpftool help**).
66
67 -V, --version
68 Print version number (similar to **bpftool version**).
69
70 -j, --json
71 Generate JSON output. For commands that cannot produce JSON, this
72 option has no effect.
73
74 -p, --pretty
75 Generate human-readable JSON output. Implies **-j**.
76
77 -d, --debug
78 Print all logs available from libbpf, including debug-level
79 information.
80
81SEE ALSO
82========
83 **bpf**\ (2),
84 **bpf-helpers**\ (7),
85 **bpftool**\ (8),
86 **bpftool-prog**\ (8),
87 **bpftool-map**\ (8),
88 **bpftool-cgroup**\ (8),
89 **bpftool-net**\ (8),
90 **bpftool-perf**\ (8),
91 **bpftool-btf**\ (8)