Re: [PATCH 09/12] perf, tools: Downgrade register mapping message to warning

From: Masami Hiramatsu
Date: Wed Nov 29 2017 - 00:56:24 EST


On Mon, 27 Nov 2017 16:23:18 -0800
Andi Kleen <andi@xxxxxxxxxxxxxx> wrote:

> From: Andi Kleen <ak@xxxxxxxxxxxxxxx>
>
> When tracing floating point code it's quite possible that perf
> doesn't recognize the register number. Downgrade the warning
> for unknown registers to a debug message.

Hmm, but without this message, user will just see ENOTSUP error.
I'm considering to introduce storage of error string
for probe-finder so that user can choose to show it or not.

Thank you,

>
> Signed-off-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>
> ---
> tools/perf/util/probe-finder.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
> index 137b2fe71838..5fe6466254f9 100644
> --- a/tools/perf/util/probe-finder.c
> +++ b/tools/perf/util/probe-finder.c
> @@ -272,8 +272,8 @@ static int convert_variable_location(Dwarf_Die *vr_die, Dwarf_Addr addr,
>
> regs = get_dwarf_regstr(regn, machine);
> if (!regs) {
> - /* This should be a bug in DWARF or this tool */
> - pr_warning("Mapping for the register number %u "
> + /* This can happen with floating point */
> + pr_debug("Mapping for the register number %u "
> "missing on this architecture.\n", regn);
> return -ENOTSUP;
> }
> --
> 2.13.6
>


--
Masami Hiramatsu <mhiramat@xxxxxxxxxx>