[bpf-next,v4,3/5] bpftool: Update documentation of "bpftool feature" command
diff mbox series

Message ID 20200226165941.6379-4-mrostecki@opensuse.org
State Accepted
Delegated to: BPF Maintainers
Headers show
  • Make probes which emit dmesg warnings optional
Related show

Commit Message

Michal Rostecki Feb. 26, 2020, 4:59 p.m. UTC
Update documentation of "bpftool feature" command with information about
new arguments: "full".

Signed-off-by: Michal Rostecki <mrostecki@opensuse.org>
 .../bpftool/Documentation/bpftool-feature.rst | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

diff mbox series

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
-|	**bpftool** **feature probe** [*COMPONENT*] [**macros** [**prefix** *PREFIX*]]
+|	**bpftool** **feature probe** [*COMPONENT*] [**full**] [**macros** [**prefix** *PREFIX*]]
 |	**bpftool** **feature help**
 |	*COMPONENT* := { **kernel** | **dev** *NAME* }
-	**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.