API headers from libbpf should not be accessed directly from the library's source directory. Instead, they should be exported with "make install_headers". Let's make sure that runqslower installs the headers properly when building. We use a libbpf_hdrs target to mark the logical dependency on libbpf's headers export for a number of object files, even though the headers should have been exported at this time (since bpftool needs them, and is required to generate the skeleton or the vmlinux.h). When descending from a parent Makefile, the specific output directories for building the library and exporting the headers are configurable with BPFOBJ_OUTPUT and BPF_DESTDIR, respectively. This is in addition to OUTPUT, on top of which those variables are constructed by default. Also adjust the Makefile for the BPF selftests. We pass a number of variables to the "make" invocation, because we want to point runqslower to the (target) libbpf shared with other tools, instead of building its own version. In addition, runqslower relies on (target) bpftool, and we also want to pass the proper variables to its Makefile so that bpftool itself reuses the same libbpf. Signed-off-by: Quentin Monnet <quentin@xxxxxxxxxxxxx> --- tools/bpf/runqslower/Makefile | 22 +++++++++++++--------- tools/testing/selftests/bpf/Makefile | 15 +++++++++------ 2 files changed, 22 insertions(+), 15 deletions(-) diff --git a/tools/bpf/runqslower/Makefile b/tools/bpf/runqslower/Makefile index 3818ec511fd2..049aef7e9a4c 100644 --- a/tools/bpf/runqslower/Makefile +++ b/tools/bpf/runqslower/Makefile @@ -9,9 +9,9 @@ BPFTOOL ?= $(DEFAULT_BPFTOOL) LIBBPF_SRC := $(abspath ../../lib/bpf) BPFOBJ_OUTPUT := $(OUTPUT)libbpf/ BPFOBJ := $(BPFOBJ_OUTPUT)libbpf.a -BPF_INCLUDE := $(BPFOBJ_OUTPUT) -INCLUDES := -I$(OUTPUT) -I$(BPF_INCLUDE) -I$(abspath ../../lib) \ - -I$(abspath ../../include/uapi) +BPF_DESTDIR := $(BPFOBJ_OUTPUT) +BPF_INCLUDE := $(BPF_DESTDIR)/include +INCLUDES := -I$(OUTPUT) -I$(BPF_INCLUDE) -I$(abspath ../../include/uapi) CFLAGS := -g -Wall # Try to detect best kernel BTF source @@ -33,7 +33,7 @@ endif .DELETE_ON_ERROR: -.PHONY: all clean runqslower +.PHONY: all clean runqslower libbpf_hdrs all: runqslower runqslower: $(OUTPUT)/runqslower @@ -46,13 +46,15 @@ clean: $(Q)$(RM) $(OUTPUT)runqslower $(Q)$(RM) -r .output +libbpf_hdrs: $(BPFOBJ) + $(OUTPUT)/runqslower: $(OUTPUT)/runqslower.o $(BPFOBJ) $(QUIET_LINK)$(CC) $(CFLAGS) $^ -lelf -lz -o $@ $(OUTPUT)/runqslower.o: runqslower.h $(OUTPUT)/runqslower.skel.h \ - $(OUTPUT)/runqslower.bpf.o + $(OUTPUT)/runqslower.bpf.o libbpf_hdrs -$(OUTPUT)/runqslower.bpf.o: $(OUTPUT)/vmlinux.h runqslower.h +$(OUTPUT)/runqslower.bpf.o: $(OUTPUT)/vmlinux.h runqslower.h libbpf_hdrs $(OUTPUT)/%.skel.h: $(OUTPUT)/%.bpf.o | $(BPFTOOL) $(QUIET_GEN)$(BPFTOOL) gen skeleton $< > $@ @@ -81,8 +83,10 @@ else endif $(BPFOBJ): $(wildcard $(LIBBPF_SRC)/*.[ch] $(LIBBPF_SRC)/Makefile) | $(BPFOBJ_OUTPUT) - $(Q)$(MAKE) $(submake_extras) -C $(LIBBPF_SRC) OUTPUT=$(BPFOBJ_OUTPUT) $@ + $(Q)$(MAKE) $(submake_extras) -C $(LIBBPF_SRC) OUTPUT=$(BPFOBJ_OUTPUT) \ + DESTDIR=$(BPFOBJ_OUTPUT) prefix= $(abspath $@) install_headers -$(DEFAULT_BPFTOOL): | $(BPFTOOL_OUTPUT) +$(DEFAULT_BPFTOOL): $(BPFOBJ) | $(BPFTOOL_OUTPUT) $(Q)$(MAKE) $(submake_extras) -C ../bpftool OUTPUT=$(BPFTOOL_OUTPUT) \ - CC=$(HOSTCC) LD=$(HOSTLD) + LIBBPF_OUTPUT=$(BPFOBJ_OUTPUT) \ + LIBBPF_DESTDIR=$(BPF_DESTDIR) CC=$(HOSTCC) LD=$(HOSTLD) diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index 9c6045261806..ffe48b40d8fa 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -130,6 +130,7 @@ HOST_INCLUDE_DIR := $(INCLUDE_DIR) endif HOST_BPFOBJ := $(HOST_BUILD_DIR)/libbpf/libbpf.a RESOLVE_BTFIDS := $(HOST_BUILD_DIR)/resolve_btfids/resolve_btfids +RUNQSLOWER_OUTPUT := $(BUILD_DIR)/runqslower/ VMLINUX_BTF_PATHS ?= $(if $(O),$(O)/vmlinux) \ $(if $(KBUILD_OUTPUT),$(KBUILD_OUTPUT)/vmlinux) \ @@ -154,7 +155,7 @@ $(notdir $(TEST_GEN_PROGS) \ # sort removes libbpf duplicates when not cross-building MAKE_DIRS := $(sort $(BUILD_DIR)/libbpf $(HOST_BUILD_DIR)/libbpf \ $(HOST_BUILD_DIR)/bpftool $(HOST_BUILD_DIR)/resolve_btfids \ - $(INCLUDE_DIR)) + $(RUNQSLOWER_OUTPUT) $(INCLUDE_DIR)) $(MAKE_DIRS): $(call msg,MKDIR,,$@) $(Q)mkdir -p $@ @@ -183,11 +184,13 @@ $(OUTPUT)/test_stub.o: test_stub.c $(BPFOBJ) DEFAULT_BPFTOOL := $(HOST_SCRATCH_DIR)/sbin/bpftool -$(OUTPUT)/runqslower: $(BPFOBJ) | $(DEFAULT_BPFTOOL) - $(Q)$(MAKE) $(submake_extras) -C $(TOOLSDIR)/bpf/runqslower \ - OUTPUT=$(SCRATCH_DIR)/ VMLINUX_BTF=$(VMLINUX_BTF) \ - BPFOBJ=$(BPFOBJ) BPF_INCLUDE=$(INCLUDE_DIR) && \ - cp $(SCRATCH_DIR)/runqslower $@ +$(OUTPUT)/runqslower: $(BPFOBJ) | $(DEFAULT_BPFTOOL) $(RUNQSLOWER_OUTPUT) + $(Q)$(MAKE) $(submake_extras) -C $(TOOLSDIR)/bpf/runqslower \ + OUTPUT=$(RUNQSLOWER_OUTPUT) VMLINUX_BTF=$(VMLINUX_BTF) \ + BPFTOOL_OUTPUT=$(BUILD_DIR)/bpftool/ \ + BPFOBJ_OUTPUT=$(BUILD_DIR)/libbpf \ + BPFOBJ=$(BPFOBJ) BPF_INCLUDE=$(INCLUDE_DIR) && \ + cp $(RUNQSLOWER_OUTPUT)runqslower $@ TEST_GEN_PROGS_EXTENDED += $(DEFAULT_BPFTOOL) -- 2.30.2