Re: [PATCH v3 09/17] perf build: Move static libbpf dependency out of prepare step

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] Removing $(LIBBPF) from `prepare` breaks the compilation of individual object files (e.g., `make util/bpf_counter.o`) and the `check` target.
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commit 37c1263c37c9d7f14cf72b110d0a12d1429501e0
Author: Ian Rogers <irogers@google.com>

perf build: Move static libbpf dependency out of prepare step

This commit moves the libbpf dependency from the general prepare step to
the specific targets that require it. This reduces serialization during the
prepare step to speed up parallel builds.

> diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf
> --- a/tools/perf/Makefile.perf
> +++ b/tools/perf/Makefile.perf

[ ... ]

> @@ -636,10 +636,6 @@ prepare: $(OUTPUT)PERF-VERSION-FILE \
>  	$(LIBSUBCMD) \
>  	$(LIBSYMBOL)
>  
> -ifdef LIBBPF_STATIC
> -prepare: $(LIBBPF)
> -endif
> -
>  $(OUTPUT)%.o: %.c prepare FORCE
>  	$(Q)$(MAKE) -f $(srctree)/tools/build/Makefile.build dir=$(build-dir) $@

Does removing this dependency from the prepare step break the compilation
of individual object files and the check target?

Since the %.o compilation rule shown above and the check target rely on
prepare, it looks like running make util/bpf_counter.o or make check in a
clean tree will proceed without first building libbpf.a and its headers.

Could this result in build failures for any C files that include BPF
headers before the library is fully built?

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Sashiko AI review · https://sashiko.dev/#/patchset/20260514163409.927816-1-irogers@google.com?part=9