Re: [PATCH v14 04/19] function_graph: Replace fgraph_ret_regs with ftrace_regs

Masami Hiramatsu
2024-10-01T12:55:18Z

On Mon, 16 Sep 2024 20:59:05 +0200
Heiko Carstens <hca@linux.ibm.com> wrote:

> On Mon, Sep 16, 2024 at 12:29:30PM -0400, Steven Rostedt wrote:
> > On Mon, 16 Sep 2024 14:16:56 +0200
> > Heiko Carstens <hca@linux.ibm.com> wrote:
> >
> > > This does not pass the ftrace selftests. Please merge the patch below
> > > into this patch. With that:
> > >
> > > Acked-by: Heiko Carstens <hca@linux.ibm.com>
> >
> > Thank you very much, this is why I wanted arch maintainers acks before
> > taking anything.
> >
> > There may be other patches in this series that I didn't Cc everyone
> > (yet). Did you look at the other patches? If not, I'll go and do the Cc.
> > It's a manual process.
>
> I just had a quick look and tried Masami's git tree with the
> topic/fprobe-on-fgraph branch and tried the ftrace selftests, which
> resulted in the provided small fix.

Thanks, and sorry, my change on s390 was wrong. I confused that
`stack_frame` can be a part of `ftrace_regs`. But at least in this
moment, `ftrace_regs` should replace only `fgraph_ret_regs`.

>
> But now that you ask, I can see that FPROBE is not available on s390
> anymore with the full series, since HAVE_FTRACE_GRAPH_FUNC is not
> available.

Right, this is required for implementing fprobe.

>
> Also the s390 variant of arch_ftrace_fill_perf_regs() seems to be
> incorrect.

Can you tell me what part will be wrong?

Thank you,

>
> Looks like some work is needed from our side.

--
Masami Hiramatsu (Google) <mhiramat@kernel.org>