Re: [PATCH 2/2] tracing: resolve enum names for function arguments via BTF

[Steven Rostedt <rostedt@goodmis.org>]

On Sun, 8 Feb 2026 21:07:37 +0800
Donglin Peng <dolinux.peng@gmail.com> wrote:
> Hi Steve,
> 
> I noticed that trace-cmd 3.4 introduced a new feature:
> 
> - Add support for showing parent functions in function graph
> 
>   If the "funcgraph-retaddr" option is set during function graph tracing,
>   the parent functions will now be displayed:
> 
>   preempt_count_add(val=65536); /* <-irq_enter_rcu */ (ret=0x10001)
> 
> However, it currently only prints the caller's entry point. I suggest
> enhancing this to include the **offset within the caller** as well. This
> would allow tools like `faddr2line` to locate the exact call site accurately.

Yeah, it makes sense to always show the offset of where it was called.
We can add that for 3.4.1.

> 
> I implemented a tool named FuncGraph[1] to convert function_graph
> ftrace output into an interactive HTML file. It leverages fastfaddr2line
> to map return addresses (e.g., __sys_bpf+0x51/0x500) to their
> corresponding call sites, such as: __sys_bpfat kernel/bpf/syscall.c:6115.
> 
> What do you think?

Sounds cool. Is this the vibe coding thing you talked about on Linked-In?

-- Steve

> 
> Thanks,
> Donglin
> 
> [1] https://github.com/pengdonglin137/FuncGraph
> 
> >
> > -- Steve
> >
> >
> >
> > [1] https://git.kernel.org/pub/scm/utils/trace-cmd/trace-cmd.git/tag/?h=trace-cmd-v3.4