Add support for building selftests with -O2 level of optimization, which allows more compiler warnings detection (like lots of potentially uninitialized usage), but also is useful to have a faster-running test for some CPU-intensive tests. One can build optimized versions of libbpf and selftests by running: $ make RELEASE=1 There is a measurable speed up of about 10 seconds for me locally, though it's mostly capped by non-parallelized serial tests. User CPU time goes down by total 40 seconds, from 1m10s to 0m28s. Unoptimized build (-O0) ======================= Summary: 430/3544 PASSED, 25 SKIPPED, 4 FAILED real 1m59.937s user 1m10.877s sys 3m14.880s Optimized build (-O2) ===================== Summary: 425/3543 PASSED, 25 SKIPPED, 9 FAILED real 1m50.540s user 0m28.406s sys 3m13.198s Acked-by: Jiri Olsa <jolsa@xxxxxxxxxx> Reviewed-by: Alan Maguire <alan.maguire@xxxxxxxxxx> Signed-off-by: Andrii Nakryiko <andrii@xxxxxxxxxx> --- tools/testing/selftests/bpf/Makefile | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index 99f66bdf7698..4225f975fce3 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -27,7 +27,9 @@ endif BPF_GCC ?= $(shell command -v bpf-gcc;) SAN_CFLAGS ?= SAN_LDFLAGS ?= $(SAN_CFLAGS) -CFLAGS += -g -O0 -rdynamic \ +RELEASE ?= +OPT_FLAGS ?= $(if $(RELEASE),-O2,-O0) +CFLAGS += -g $(OPT_FLAGS) -rdynamic \ -Wall -Werror \ $(GENFLAGS) $(SAN_CFLAGS) \ -I$(CURDIR) -I$(INCLUDE_DIR) -I$(GENDIR) -I$(LIBDIR) \ @@ -243,7 +245,7 @@ $(OUTPUT)/runqslower: $(BPFOBJ) | $(DEFAULT_BPFTOOL) $(RUNQSLOWER_OUTPUT) BPFTOOL_OUTPUT=$(HOST_BUILD_DIR)/bpftool/ \ BPFOBJ_OUTPUT=$(BUILD_DIR)/libbpf \ BPFOBJ=$(BPFOBJ) BPF_INCLUDE=$(INCLUDE_DIR) \ - EXTRA_CFLAGS='-g -O0 $(SAN_CFLAGS)' \ + EXTRA_CFLAGS='-g $(OPT_FLAGS) $(SAN_CFLAGS)' \ EXTRA_LDFLAGS='$(SAN_LDFLAGS)' && \ cp $(RUNQSLOWER_OUTPUT)runqslower $@ @@ -281,7 +283,7 @@ $(DEFAULT_BPFTOOL): $(wildcard $(BPFTOOLDIR)/*.[ch] $(BPFTOOLDIR)/Makefile) \ $(HOST_BPFOBJ) | $(HOST_BUILD_DIR)/bpftool $(Q)$(MAKE) $(submake_extras) -C $(BPFTOOLDIR) \ ARCH= CROSS_COMPILE= CC="$(HOSTCC)" LD="$(HOSTLD)" \ - EXTRA_CFLAGS='-g -O0' \ + EXTRA_CFLAGS='-g $(OPT_FLAGS)' \ OUTPUT=$(HOST_BUILD_DIR)/bpftool/ \ LIBBPF_OUTPUT=$(HOST_BUILD_DIR)/libbpf/ \ LIBBPF_DESTDIR=$(HOST_SCRATCH_DIR)/ \ @@ -292,7 +294,7 @@ $(CROSS_BPFTOOL): $(wildcard $(BPFTOOLDIR)/*.[ch] $(BPFTOOLDIR)/Makefile) \ $(BPFOBJ) | $(BUILD_DIR)/bpftool $(Q)$(MAKE) $(submake_extras) -C $(BPFTOOLDIR) \ ARCH=$(ARCH) CROSS_COMPILE=$(CROSS_COMPILE) \ - EXTRA_CFLAGS='-g -O0' \ + EXTRA_CFLAGS='-g $(OPT_FLAGS)' \ OUTPUT=$(BUILD_DIR)/bpftool/ \ LIBBPF_OUTPUT=$(BUILD_DIR)/libbpf/ \ LIBBPF_DESTDIR=$(SCRATCH_DIR)/ \ @@ -315,7 +317,7 @@ $(BPFOBJ): $(wildcard $(BPFDIR)/*.[ch] $(BPFDIR)/Makefile) \ $(APIDIR)/linux/bpf.h \ | $(BUILD_DIR)/libbpf $(Q)$(MAKE) $(submake_extras) -C $(BPFDIR) OUTPUT=$(BUILD_DIR)/libbpf/ \ - EXTRA_CFLAGS='-g -O0 $(SAN_CFLAGS)' \ + EXTRA_CFLAGS='-g $(OPT_FLAGS) $(SAN_CFLAGS)' \ EXTRA_LDFLAGS='$(SAN_LDFLAGS)' \ DESTDIR=$(SCRATCH_DIR) prefix= all install_headers @@ -324,7 +326,7 @@ $(HOST_BPFOBJ): $(wildcard $(BPFDIR)/*.[ch] $(BPFDIR)/Makefile) \ $(APIDIR)/linux/bpf.h \ | $(HOST_BUILD_DIR)/libbpf $(Q)$(MAKE) $(submake_extras) -C $(BPFDIR) \ - EXTRA_CFLAGS='-g -O0' ARCH= CROSS_COMPILE= \ + EXTRA_CFLAGS='-g $(OPT_FLAGS)' ARCH= CROSS_COMPILE= \ OUTPUT=$(HOST_BUILD_DIR)/libbpf/ \ CC="$(HOSTCC)" LD="$(HOSTLD)" \ DESTDIR=$(HOST_SCRATCH_DIR)/ prefix= all install_headers -- 2.34.1
