| =============== |
| bpftool-feature |
| =============== |
| ------------------------------------------------------------------------------- |
| tool for inspection of eBPF-related parameters for Linux kernel or net device |
| ------------------------------------------------------------------------------- |
| |
| :Manual section: 8 |
| |
| SYNOPSIS |
| ======== |
| |
| **bpftool** [*OPTIONS*] **feature** *COMMAND* |
| |
| *OPTIONS* := { { **-j** | **--json** } [{ **-p** | **--pretty** }] } |
| |
| *COMMANDS* := { **probe** | **help** } |
| |
| FEATURE COMMANDS |
| ================ |
| |
| | **bpftool** **feature probe** [*COMPONENT*] [**full**] [**macros** [**prefix** *PREFIX*]] |
| | **bpftool** **feature help** |
| | |
| | *COMPONENT* := { **kernel** | **dev** *NAME* } |
| |
| DESCRIPTION |
| =========== |
| **bpftool feature probe** [**kernel**] [**full**] [**macros** [**prefix** *PREFIX*]] |
| Probe the running kernel and dump a number of eBPF-related |
| parameters, such as availability of the **bpf()** system call, |
| JIT status, eBPF program types availability, eBPF helper |
| functions availability, and more. |
| |
| By default, bpftool **does not run probes** for |
| **bpf_probe_write_user**\ () and **bpf_trace_printk**\() |
| helpers which print warnings to kernel logs. To enable them |
| and run all probes, the **full** keyword should be used. |
| |
| If the **macros** keyword (but not the **-j** option) is |
| passed, a subset of the output is dumped as a list of |
| **#define** macros that are ready to be included in a C |
| header file, for example. If, additionally, **prefix** is |
| used to define a *PREFIX*, the provided string will be used |
| as a prefix to the names of the macros: this can be used to |
| avoid conflicts on macro names when including the output of |
| this command as a header file. |
| |
| Keyword **kernel** can be omitted. If no probe target is |
| specified, probing the kernel is the default behaviour. |
| |
| **bpftool feature probe dev** *NAME* [**full**] [**macros** [**prefix** *PREFIX*]] |
| Probe network device for supported eBPF features and dump |
| results to the console. |
| |
| The keywords **full**, **macros** and **prefix** have the |
| same role as when probing the kernel. |
| |
| **bpftool feature 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**. |
| |
| -d, --debug |
| Print all logs available from libbpf, including debug-level |
| information. |
| |
| SEE ALSO |
| ======== |
| **bpf**\ (2), |
| **bpf-helpers**\ (7), |
| **bpftool**\ (8), |
| **bpftool-prog**\ (8), |
| **bpftool-map**\ (8), |
| **bpftool-cgroup**\ (8), |
| **bpftool-net**\ (8), |
| **bpftool-perf**\ (8), |
| **bpftool-btf**\ (8) |