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| author | Alan Maguire <alan.maguire@oracle.com> | 2020-08-07 13:50:29 +0200 |
|---|---|---|
| committer | Daniel Borkmann <daniel@iogearbox.net> | 2020-08-07 18:44:56 +0200 |
| commit | 7fb20f9e901e6df2f7dc032d88da5abff4117d37 (patch) | |
| tree | 056b7d8a81a622376a675a16c2404e7474263595 /Documentation | |
| parent | bpf: Fix compilation warning of selftests (diff) | |
| download | linux-7fb20f9e901e6df2f7dc032d88da5abff4117d37.tar.xz linux-7fb20f9e901e6df2f7dc032d88da5abff4117d37.zip | |
bpf, doc: Remove references to warning message when using bpf_trace_printk()
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 <alan.maguire@oracle.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/1596801029-32395-1-git-send-email-alan.maguire@oracle.com
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/bpf/bpf_design_QA.rst | 11 |
1 files changed, 0 insertions, 11 deletions
diff --git a/Documentation/bpf/bpf_design_QA.rst b/Documentation/bpf/bpf_design_QA.rst index 12a246fcf6cb..2df7b067ab93 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 |