From 13e17c9ff49119aa2826dbf1e130f34d4d7a55d9 Mon Sep 17 00:00:00 2001 From: Ian Rogers Date: Mon, 28 Oct 2024 12:36:19 -0700 Subject: [PATCH] perf build: Make libunwind opt-in rather than opt-out Having multiple unwinding libraries makes the perf code harder to understand and we have unused/untested code paths. Perf made BPF support an opt-out rather than opt-in feature. As libbpf has a libelf dependency, elfutils that provides libelf will also provide libdw. When libdw is present perf will use libdw unwinding rather than libunwind unwinding even if libunwind support is compiled in. Rather than have libunwind built into perf and never used, explicitly disable the support and make it opt-in. Signed-off-by: Ian Rogers Tested-by: Arnaldo Carvalho de Melo Link: https://lore.kernel.org/r/20241028193619.247727-1-irogers@google.com Closes: https://lore.kernel.org/linux-perf-users/CAP-5=fUXkp-d7gkzX4eF+nbjb2978dZsiHZ9abGHN=BN1qAcbg@mail.gmail.com/ Signed-off-by: Namhyung Kim --- tools/perf/Makefile.config | 4 ++++ tools/perf/Makefile.perf | 2 +- tools/perf/tests/make | 6 +++--- 3 files changed, 8 insertions(+), 4 deletions(-) diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config index 8da6d91b7ad51..e68f0be259a19 100644 --- a/tools/perf/Makefile.config +++ b/tools/perf/Makefile.config @@ -95,6 +95,10 @@ ifneq ($(SRCARCH),$(filter $(SRCARCH),x86 arm arm64 powerpc s390 csky riscv loon NO_LIBDW_DWARF_UNWIND := 1 endif +ifneq ($(LIBUNWIND),1) + NO_LIBUNWIND := 1 +endif + ifeq ($(LIBUNWIND_LIBS),) NO_LIBUNWIND := 1 endif diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf index b4dee7c20ed15..d74241a151313 100644 --- a/tools/perf/Makefile.perf +++ b/tools/perf/Makefile.perf @@ -52,7 +52,7 @@ include ../scripts/utilities.mak # # Define NO_LIBELF if you do not want libelf dependency (e.g. cross-builds) # -# Define NO_LIBUNWIND if you do not want libunwind dependency for dwarf +# Define LIBUNWIND if you do not want libunwind dependency for dwarf # backtrace post unwind. # # Define NO_BACKTRACE if you do not want stack backtrace debug feature diff --git a/tools/perf/tests/make b/tools/perf/tests/make index a5040772043f6..a7fcbd589752a 100644 --- a/tools/perf/tests/make +++ b/tools/perf/tests/make @@ -81,7 +81,7 @@ make_no_gtk2 := NO_GTK2=1 make_no_ui := NO_SLANG=1 NO_GTK2=1 make_no_demangle := NO_DEMANGLE=1 make_no_libelf := NO_LIBELF=1 -make_no_libunwind := NO_LIBUNWIND=1 +make_libunwind := LIBUNWIND=1 make_no_libdw_dwarf_unwind := NO_LIBDW_DWARF_UNWIND=1 make_no_backtrace := NO_BACKTRACE=1 make_no_libcapstone := NO_CAPSTONE=1 @@ -121,7 +121,7 @@ make_static := LDFLAGS=-static NO_PERF_READ_VDSO32=1 NO_PERF_READ_VDSOX3 # all the NO_* variable combined make_minimal := NO_LIBPERL=1 NO_LIBPYTHON=1 NO_GTK2=1 -make_minimal += NO_DEMANGLE=1 NO_LIBELF=1 NO_LIBUNWIND=1 NO_BACKTRACE=1 +make_minimal += NO_DEMANGLE=1 NO_LIBELF=1 NO_BACKTRACE=1 make_minimal += NO_LIBNUMA=1 NO_LIBAUDIT=1 NO_LIBBIONIC=1 make_minimal += NO_LIBDW_DWARF_UNWIND=1 NO_AUXTRACE=1 NO_LIBBPF=1 make_minimal += NO_LIBCRYPTO=1 NO_SDT=1 NO_JVMTI=1 NO_LIBZSTD=1 @@ -153,7 +153,7 @@ run += make_no_gtk2 run += make_no_ui run += make_no_demangle run += make_no_libelf -run += make_no_libunwind +run += make_libunwind run += make_no_libdw_dwarf_unwind run += make_no_backtrace run += make_no_libcapstone -- 2.39.5