From bcdacab6e70cf90bf3d8db94ae9226ff5117a61e Mon Sep 17 00:00:00 2001 From: Michal Rostecki Date: Wed, 26 Feb 2020 17:59:37 +0100 Subject: bpftool: Update documentation of "bpftool feature" command Update documentation of "bpftool feature" command with information about new arguments: "full". Signed-off-by: Michal Rostecki Signed-off-by: Daniel Borkmann Reviewed-by: Quentin Monnet Link: https://lore.kernel.org/bpf/20200226165941.6379-4-mrostecki@opensuse.org --- tools/bpf/bpftool/Documentation/bpftool-feature.rst | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) (limited to 'tools/bpf') diff --git a/tools/bpf/bpftool/Documentation/bpftool-feature.rst b/tools/bpf/bpftool/Documentation/bpftool-feature.rst index 4d08f35034a2..b04156cfd7a3 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-feature.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-feature.rst @@ -19,19 +19,24 @@ SYNOPSIS FEATURE COMMANDS ================ -| **bpftool** **feature probe** [*COMPONENT*] [**macros** [**prefix** *PREFIX*]] +| **bpftool** **feature probe** [*COMPONENT*] [**full**] [**macros** [**prefix** *PREFIX*]] | **bpftool** **feature help** | | *COMPONENT* := { **kernel** | **dev** *NAME* } DESCRIPTION =========== - **bpftool feature probe** [**kernel**] [**macros** [**prefix** *PREFIX*]] + **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 @@ -44,16 +49,12 @@ DESCRIPTION Keyword **kernel** can be omitted. If no probe target is specified, probing the kernel is the default behaviour. - Note that when probed, some eBPF helpers (e.g. - **bpf_trace_printk**\ () or **bpf_probe_write_user**\ ()) may - print warnings to kernel logs. - - **bpftool feature probe dev** *NAME* [**macros** [**prefix** *PREFIX*]] + **bpftool feature probe dev** *NAME* [**full**] [**macros** [**prefix** *PREFIX*]] Probe network device for supported eBPF features and dump results to the console. - The two keywords **macros** and **prefix** have the same - role as when probing the kernel. + The keywords **full**, **macros** and **prefix** have the + same role as when probing the kernel. **bpftool feature help** Print short help message. -- cgit