[PATCH bpf] bpf: doc: remove references to warning message when using bpf_trace_printk()
From: Alan Maguire <hidden>
Date: 2020-08-07 11:51:47
Also in:
bpf, linux-doc, lkml
Subsystem:
bpf [general] (safe dynamic programs and tools), documentation, the rest · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Jonathan Corbet, Linus Torvalds
The BPF helper bpf_trace_printk() no longer uses trace_printk();
it is now triggers a dedicated trace event. Hence the described
warning is no longer present, so remove the discussion of it as
it may confuse people.
Fixes: ac5a72ea5c89 ("bpf: Use dedicated bpf_trace_printk event instead of trace_printk()")
Signed-off-by: Alan Maguire <redacted>
---
Documentation/bpf/bpf_design_QA.rst | 11 -----------
1 file changed, 11 deletions(-)
diff --git a/Documentation/bpf/bpf_design_QA.rst b/Documentation/bpf/bpf_design_QA.rst
index 12a246f..2df7b06 100644
--- a/Documentation/bpf/bpf_design_QA.rst
+++ b/Documentation/bpf/bpf_design_QA.rst@@ -246,17 +246,6 @@ program is loaded the kernel will print warning message, so this helper is only useful for experiments and prototypes. Tracing BPF programs are root only. -Q: bpf_trace_printk() helper warning ------------------------------------- -Q: When bpf_trace_printk() helper is used the kernel prints nasty -warning message. Why is that? - -A: This is done to nudge program authors into better interfaces when -programs need to pass data to user space. Like bpf_perf_event_output() -can be used to efficiently stream data via perf ring buffer. -BPF maps can be used for asynchronous data sharing between kernel -and user space. bpf_trace_printk() should only be used for debugging. - Q: New functionality via kernel modules? ---------------------------------------- Q: Can BPF functionality such as new program or map types, new
--
1.8.3.1