[PATCH v5 4/7] perf unwind-libunwind: Make libunwind register reading cross platform

[Ian Rogers]

On Fri, May 15, 2026 at 1:48 PM Arnaldo Carvalho de Melo
<acme at kernel.org> wrote:
>
> On Fri, May 15, 2026 at 12:38:48PM -0700, Ian Rogers wrote:
> > On Fri, May 15, 2026 at 12:23 PM Arnaldo Carvalho de Melo <acme at kernel.org> wrote:
>
> > > +++ b/tools/perf/util/libunwind-arch/libunwind-ppc32.c
> > > @@ -23,6 +23,8 @@ int __get_perf_regnum_for_unw_regnum_ppc32(int unw_regnum __maybe_unused)
> > >                 return PERF_REG_POWERPC_CTR;
> > >         case UNW_PPC32_XER:
> > >                 return PERF_REG_POWERPC_XER;
> > > +       case UNW_PPC32_NIP:
> > > +               return PERF_REG_POWERPC_NIP;
> > >         default:
> > >                 pr_err("unwind: invalid reg id %d\n", unw_regnum);
> > >                 return -EINVAL;
> > > ⬢ [acme at toolbx perf-tools-next]$
>
> > > Ok? It was the only issue found in this patch.
>
> > Looks good, the NIP is in the original code that I copied, so I don't
> > understand how I lost this, but good catch!
>
> What I have is in tmp.perf-tools-next, doing a container build now,
> still need to look at the other findings, but they seems either trivial
> or complaints about making  the build time more inneficient by not
> caching some feature tests, so I think I'll fix the trivial like I did
> in the above case (posting diffs to the list) and leave the build time
> for later so that we make progress.
>
> Will try to do this later today so that I publish it to perf-tools-next
> for it to soak a bit in linux-next.

This is great! Thank you Arnaldo!
Ian

> - Arnaldo