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*] [**macros** [**prefix** *PREFIX*]] 23| **bpftool** **feature help** 24| 25| *COMPONENT* := { **kernel** | **dev** *NAME* } 26 27DESCRIPTION 28=========== 29 **bpftool feature probe** [**kernel**] [**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 If the **macros** keyword (but not the **-j** option) is 36 passed, a subset of the output is dumped as a list of 37 **#define** macros that are ready to be included in a C 38 header file, for example. If, additionally, **prefix** is 39 used to define a *PREFIX*, the provided string will be used 40 as a prefix to the names of the macros: this can be used to 41 avoid conflicts on macro names when including the output of 42 this command as a header file. 43 44 Keyword **kernel** can be omitted. If no probe target is 45 specified, probing the kernel is the default behaviour. 46 47 Note that when probed, some eBPF helpers (e.g. 48 **bpf_trace_printk**\ () or **bpf_probe_write_user**\ ()) may 49 print warnings to kernel logs. 50 51 **bpftool feature probe dev** *NAME* [**macros** [**prefix** *PREFIX*]] 52 Probe network device for supported eBPF features and dump 53 results to the console. 54 55 The two keywords **macros** and **prefix** have the same 56 role as when probing the kernel. 57 58 **bpftool feature help** 59 Print short help message. 60 61OPTIONS 62======= 63 -h, --help 64 Print short generic help message (similar to **bpftool help**). 65 66 -V, --version 67 Print version number (similar to **bpftool version**). 68 69 -j, --json 70 Generate JSON output. For commands that cannot produce JSON, this 71 option has no effect. 72 73 -p, --pretty 74 Generate human-readable JSON output. Implies **-j**. 75 76 -d, --debug 77 Print all logs available from libbpf, including debug-level 78 information. 79 80SEE ALSO 81======== 82 **bpf**\ (2), 83 **bpf-helpers**\ (7), 84 **bpftool**\ (8), 85 **bpftool-prog**\ (8), 86 **bpftool-map**\ (8), 87 **bpftool-cgroup**\ (8), 88 **bpftool-net**\ (8), 89 **bpftool-perf**\ (8), 90 **bpftool-btf**\ (8) 91