Re: [PATCH] perf build: prevent "argument list too long" error

[Ian Rogers]

On Tue, Mar 3, 2026 at 2:47 PM Markus Mayer <mmayer@xxxxxxxxxxxx> wrote:
>
> On Tue, 3 Mar 2026 at 14:35, Ian Rogers <irogers@xxxxxxxxxx> wrote:
> >
> > On Tue, Mar 3, 2026 at 1:16 PM Markus Mayer <mmayer@xxxxxxxxxxxx> wrote:
> > >
> > >   TEST    [...]/arm64/build/linux-custom/tools/perf/pmu-events/metric_test.log
> > > make[5]: /bin/sh: Argument list too long
> > > make[5]: *** [pmu-events/Build:217: prune_orphans] Error 127
> > > make[5]: *** Waiting for unfinished jobs....
> > > make[4]: *** [Makefile.perf:773: [...]/tools/perf/pmu-events/pmu-events-in.o] Error 2
> > > make[4]: *** Waiting for unfinished jobs....
> > > make[3]: *** [Makefile.perf:289: sub-make] Error 2
> >
> > As with:
> > https://lore.kernel.org/lkml/20250728093153.2330009-1-changqing.li@xxxxxxxxxxxxx/
> > I'm not able to reproduce the problem but the change makes sense.
> >
> > Reviewed-by: Ian Rogers <irogers@xxxxxxxxxx>
>
> Thanks for the review. Not sure what makes my setup different from
> yours. FWIW, it's an ARM64 cross-compile. I had the build system dump
> the contents of $(ORPHAN_FILES) into a file for me. This is how many
> files it was trying to pass via the shell:
>
> $ wc -l json_files.txt
> 634 json_files.txt
>
> Maybe you have fewer orphans to prune or your shell has a higher the
> argument limit. Whatever the case, both our automated nightly builds
> and manual builds have been running into this issue.

Yes, building an x86 version and then cross-compiling for ARM would
create a large set of orphan files requiring cleanup. Trying that with
a giant output directory path I couldn't trigger a breakage, but I
think I just have a very generous MAX_ARGS.

Thanks,
Ian

> Regards,
> -Markus