diff options
author | Kumar Kartikeya Dwivedi <memxor@gmail.com> | 2025-07-03 13:48:17 -0700 |
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committer | Alexei Starovoitov <ast@kernel.org> | 2025-07-03 19:30:07 -0700 |
commit | 876f5ebd58a9ac42f48a7ead3d5b274a314e0ace (patch) | |
tree | fb5461f331ddb21c035abb683ba70362363443cf /tools/bpf/bpftool/Documentation | |
parent | 3bbc1ba9cc0d9a7ccc194883489a4e460ca5080b (diff) |
bpftool: Add support for dumping streams
Add support for printing the BPF stream contents of a program in
bpftool. The new bpftool prog tracelog command is extended to take
stdout and stderr arguments, and then the prog specification.
The bpf_prog_stream_read() API added in previous patch is simply reused
to grab data and then it is dumped to the respective file. The stdout
data is sent to stdout, and stderr is printed to stderr.
Cc: Quentin Monnet <qmo@kernel.org>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20250703204818.925464-12-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'tools/bpf/bpftool/Documentation')
-rw-r--r-- | tools/bpf/bpftool/Documentation/bpftool-prog.rst | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/tools/bpf/bpftool/Documentation/bpftool-prog.rst b/tools/bpf/bpftool/Documentation/bpftool-prog.rst index da3152c16228..f69fd92df8d8 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-prog.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-prog.rst @@ -35,6 +35,7 @@ PROG COMMANDS | **bpftool** **prog attach** *PROG* *ATTACH_TYPE* [*MAP*] | **bpftool** **prog detach** *PROG* *ATTACH_TYPE* [*MAP*] | **bpftool** **prog tracelog** +| **bpftool** **prog tracelog** [ { **stdout** | **stderr** } *PROG* ] | **bpftool** **prog run** *PROG* **data_in** *FILE* [**data_out** *FILE* [**data_size_out** *L*]] [**ctx_in** *FILE* [**ctx_out** *FILE* [**ctx_size_out** *M*]]] [**repeat** *N*] | **bpftool** **prog profile** *PROG* [**duration** *DURATION*] *METRICs* | **bpftool** **prog help** @@ -179,6 +180,12 @@ bpftool prog tracelog purposes. For streaming data from BPF programs to user space, one can use perf events (see also **bpftool-map**\ (8)). +bpftool prog tracelog { stdout | stderr } *PROG* + Dump the BPF stream of the program. BPF programs can write to these streams + at runtime with the **bpf_stream_vprintk**\ () kfunc. The kernel may write + error messages to the standard error stream. This facility should be used + only for debugging purposes. + bpftool prog run *PROG* data_in *FILE* [data_out *FILE* [data_size_out *L*]] [ctx_in *FILE* [ctx_out *FILE* [ctx_size_out *M*]]] [repeat *N*] Run BPF program *PROG* in the kernel testing infrastructure for BPF, meaning that the program works on the data and context provided by the |