Re: [PATCH] perf inject: Keep build-ID data if no option is used

From: Arnaldo Carvalho de Melo

Date: Tue Jan 13 2026 - 15:16:41 EST


On Thu, Jan 08, 2026 at 03:57:28PM -0800, Namhyung Kim wrote:
> Hi Ian,
>
> On Wed, Dec 17, 2025 at 10:57:01AM -0800, Ian Rogers wrote:
> > On Wed, Dec 17, 2025 at 10:39 AM Namhyung Kim <namhyung@xxxxxxxxxx> wrote:
> > >
> > > The keep_feat() determines which header features will be kept or
> > > discarded. Usually perf inject will add build-IDs based on -b, -B or
> > > other related options. But it lose build-ID when none of those options
> > > are used. This is meaningful only when --buildid-mmap is not used.
> > >
> > > The following example shows the impact of this change.
> > >
> > > $ perf record --no-buildid-mmap true
> > > [ perf record: Woken up 1 times to write data ]
> > > [ perf record: Captured and wrote 0.037 MB perf.data (5 samples) ]
> > >
> > > $ perf inject -i perf.data -o perf.data.inject
> > >
> > > $ perf buildid-list -i perf.data
> > > 08cccc2a9388d5247ccb3e864f3063b975b0a15d /usr/lib/x86_64-linux-gnu/ld-linux-x86-64.so.2
> > > fd5c4d5673256cd6bda51725dba048dabb0f854e [kernel.kallsyms]
> > > 97a36ce1140071be5c36b147fa0bed173e05a602 [vdso]
> > >
> > > $ perf buildid-list -i perf.data.inject
> > > 97a36ce1140071be5c36b147fa0bed173e05a602 [vdso]
> > >
> > > With this change, perf.data.inject would show the same list (of course,
> > > you need to run perf inject again).
> > >
> > > Reported-by: Gabriel Marin <gmx@xxxxxxxxxx>
> > > Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
> >
> > Reviewed-by: Ian Rogers <irogers@xxxxxxxxxx>
>
> Thanks for the review!
>
> Arnaldo, any chance you can pick this up soon?

Thanks, applied to perf-tools-next,

- Arnaldo