From 8524d71cebfa6ddcfbb89f0fe0e174c8d0477c6d Mon Sep 17 00:00:00 2001 From: Ian Rogers Date: Wed, 20 Mar 2024 09:32:44 -0700 Subject: [PATCH] perf build: Pretend scandirat is missing with msan Memory sanitizer lacks an interceptor for scandirat, reporting all memory it allocates as uninitialized. Memory sanitizer has a scandir interceptor so use the fallback function in this case. This allows 'perf test' to run under memory sanitizer. Additional notes from Ian on running in this mode: Note, as msan needs to instrument memory allocations libraries need to be compiled with it. I lacked the msan built libraries and so built with: ``` $ make -C tools/perf O=/tmp/perf DEBUG=1 EXTRA_CFLAGS="-O0 -g -fno-omit-frame-pointer -fsanitize=memory -fsanitize-memory-track-origins" CC=clang CXX=clang++ HOSTCC=clang NO_LIBTRACEEVENT=1 NO_LIBELF=1 BUILD_BPF_SKEL=0 NO_LIBPFM=1 ``` oh, I disabled libbpf here as the bpf system call also lacks msan interceptors. Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Ingo Molnar Cc: Jiri Olsa Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Link: https://lore.kernel.org/r/20240320163244.1287780-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/Makefile.config | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config index 7783479de6917..7f1e016a92536 100644 --- a/tools/perf/Makefile.config +++ b/tools/perf/Makefile.config @@ -496,7 +496,10 @@ ifdef NO_DWARF endif ifeq ($(feature-scandirat), 1) - CFLAGS += -DHAVE_SCANDIRAT_SUPPORT + # Ignore having scandirat with memory sanitizer that lacks an interceptor. + ifeq ($(filter s% -fsanitize=memory%,$(EXTRA_CFLAGS),),) + CFLAGS += -DHAVE_SCANDIRAT_SUPPORT + endif endif ifeq ($(feature-sched_getcpu), 1) -- 2.30.2