Re: [PATCH] perf: Don't show unwind error messages when augmenting frame pointer stack

From: Arnaldo Carvalho de Melo
Date: Sat Apr 09 2022 - 11:07:26 EST


Em Fri, Apr 08, 2022 at 03:12:15PM +0100, John Garry escreveu:
> On 06/04/2022 15:56, James Clark wrote:
> > Commit b9f6fbb3b2c2 ("perf arm64: Inject missing frames when using 'perf
> > record --call-graph=fp'") intended to add a 'best effort' Dwarf unwind
> > that improved the frame pointer stack in most scenarios. It's expected
> > that the unwind will fail sometimes, but this shouldn't be reported as
> > an error. It only works when the return address can be determined from
> > the contents of the link register alone.
> >
> > Fix the error shown when the unwinder requires extra registers by adding
> > a new flag that suppresses error messages. This flag is not set in the
> > normal --call-graph=dwarf unwind mode so that behavior is not changed.
> >
> > Reported-by: John Garry <john.garry@xxxxxxxxxx>
> > Fixes: b9f6fbb3b2c2 ("perf arm64: Inject missing frames when using 'perf record --call-graph=fp'")
> > Signed-off-by: James Clark <james.clark@xxxxxxx>
>
> Seems ok:
> Tested-by: John Garry <john.garry@xxxxxxxxxx>

Thanks, applied.

- Arnaldo