Subject: Re: [PATCH v4 bpf-next 5/7] selftests/bpf: replace test_progs and test_maps w/ general rule

From: Stanislav Fomichev <[email-masked]>
Date: Wed, 16 Oct 2019 09:32:49 -0700

On 10/15, Andrii Nakryiko wrote:
> Define test runner generation meta-rule that codifies dependencies
> between test runner, its tests, and its dependent BPF programs. Use that
> for defining test_progs and test_maps test-runners. Also additionally define
> 2 flavors of test_progs:
> - alu32, which builds BPF programs with 32-bit registers codegen;
> - bpf_gcc, which build BPF programs using GCC, if it supports BPF target.
Question:

Why not merge test_maps tests into test_progs framework and have a
single binary instead of doing all this makefile-related work?
We can independently address the story with alu32/gcc progs (presumably
in the same manner, with make defines).

I can hardly follow the existing makefile and now with the evals it's
10x more complicated for no good reason.

> Overall, this is accomplished through $(eval)'ing a set of generic
> rules, which defines Makefile targets dynamically at runtime. See
> comments explaining the need for 2 $(evals), though.
> 
> For each test runner we have (test_maps and test_progs, currently), and,
> optionally, their flavors, the logic of build process is modeled as
> follows (using test_progs as an example):
> - all BPF objects are in progs/:
>   - BPF object's .o file is built into output directory from
>     corresponding progs/.c file;
>   - all BPF objects in progs/*.c depend on all progs/*.h headers;
>   - all BPF objects depend on bpf_*.h helpers from libbpf (but not
>     libbpf archive). There is an extra rule to trigger bpf_helper_defs.h
>     (re-)build, if it's not present/outdated);
>   - build recipe for BPF object can be re-defined per test runner/flavor;
> - test files are built from prog_tests/*.c:
>   - all such test file objects are built on individual file basis;
>   - currently, every single test file depends on all BPF object files;
>     this might be improved in follow up patches to do 1-to-1 dependency,
>     but allowing to customize this per each individual test;
>   - each test runner definition can specify a list of extra .c and .h
>     files to be built along test files and test runner binary; all such
>     headers are becoming automatic dependency of each test .c file;
>   - due to test files sometimes embedding (using .incbin assembly
>     directive) contents of some BPF objects at compilation time, which are
>     expected to be in CWD of compiler, compilation for test file object does
>     cd into test runner's output directory; to support this mode all the
>     include paths are turned into absolute paths using $(abspath) make
>     function;
> - prog_tests/test.h is automatically (re-)generated with an entry for
>   each .c file in prog_tests/;
> - final test runner binary is linked together from test object files and
>   extra object files, linking together libbpf's archive as well;
> - it's possible to specify extra "resource" files/targets, which will be
>   copied into test runner output directory, if it differes from
>   Makefile-wide $(OUTPUT). This is used to ensure btf_dump test cases and
>   urandom_read binary is put into a test runner's CWD for tests to find
>   them in runtime.
> 
> For flavored test runners, their output directory is a subdirectory of
> common Makefile-wide $(OUTPUT) directory with flavor name used as
> subdirectory name.
> 
> BPF objects targets might be reused between different test runners, so
> extra checks are employed to not double-define them. Similarly, we have
> redefinition guards for output directories and test headers.
> 
> test_verifier follows slightly different patterns and is simple enough
> to not justify generalizing TEST_RUNNER_DEFINE/TEST_RUNNER_DEFINE_RULES
> further to accomodate these differences. Instead, rules for
> test_verifier are minimized and simplified, while preserving correctness
> of dependencies.
> 
> Signed-off-by: Andrii Nakryiko <[email-masked]>
> ---
>  tools/testing/selftests/bpf/.gitignore |   5 +-
>  tools/testing/selftests/bpf/Makefile   | 313 ++++++++++++++-----------
>  2 files changed, 180 insertions(+), 138 deletions(-)
> 
> diff --git a/tools/testing/selftests/bpf/.gitignore b/tools/testing/selftests/bpf/.gitignore
> index 7470327edcfe..c51f356f84b5 100644
> --- a/tools/testing/selftests/bpf/.gitignore
> +++ b/tools/testing/selftests/bpf/.gitignore
> @@ -7,7 +7,7 @@ FEATURE-DUMP.libbpf
>  fixdep
>  test_align
>  test_dev_cgroup
> -test_progs
> +/test_progs*
>  test_tcpbpf_user
>  test_verifier_log
>  feature
> @@ -33,9 +33,10 @@ test_tcpnotify_user
>  test_libbpf
>  test_tcp_check_syncookie_user
>  test_sysctl
> -alu32
>  libbpf.pc
>  libbpf.so.*
>  test_hashmap
>  test_btf_dump
>  xdping
> +/alu32
> +/bpf_gcc
> diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
> index fbced23935cc..c9f43d49eac9 100644
> --- a/tools/testing/selftests/bpf/Makefile
> +++ b/tools/testing/selftests/bpf/Makefile
> @@ -2,10 +2,12 @@
>  include ../../../../scripts/Kbuild.include
>  include ../../../scripts/Makefile.arch
>  
> -LIBDIR := ../../../lib
> +CURDIR := $(abspath .)
> +LIBDIR := $(abspath ../../../lib)
>  BPFDIR := $(LIBDIR)/bpf
> -APIDIR := ../../../include/uapi
> -GENDIR := ../../../../include/generated
> +TOOLSDIR := $(abspath ../../../include)
> +APIDIR := $(TOOLSDIR)/uapi
> +GENDIR := $(abspath ../../../../include/generated)
>  GENHDR := $(GENDIR)/autoconf.h
>  
>  ifneq ($(wildcard $(GENHDR)),)
> @@ -16,8 +18,9 @@ CLANG		?= clang
>  LLC		?= llc
>  LLVM_OBJCOPY	?= llvm-objcopy
>  BPF_GCC		?= $(shell command -v bpf-gcc;)
> -CFLAGS += -g -Wall -O2 -I$(APIDIR) -I$(LIBDIR) -I$(BPFDIR) -I$(GENDIR) $(GENFLAGS) -I../../../include \
> -	  -Dbpf_prog_load=bpf_prog_test_load \
> +CFLAGS += -g -Wall -O2 $(GENFLAGS) -I$(APIDIR) -I$(LIBDIR) -I$(BPFDIR)	\
> +	  -I$(GENDIR) -I$(TOOLSDIR) -I$(CURDIR)				\
> +	  -Dbpf_prog_load=bpf_prog_test_load				\
>  	  -Dbpf_load_program=bpf_test_load_program
>  LDLIBS += -lcap -lelf -lrt -lpthread
>  
> @@ -29,12 +32,6 @@ TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test
>  	test_netcnt test_tcpnotify_user test_sock_fields test_sysctl test_hashmap \
>  	test_cgroup_attach xdping
>  
> -BPF_OBJ_FILES = $(patsubst %.c,%.o, $(notdir $(wildcard progs/*.c)))
> -TEST_GEN_FILES = $(BPF_OBJ_FILES)
> -
> -BTF_C_FILES = $(wildcard progs/btf_dump_test_case_*.c)
> -TEST_FILES = $(BTF_C_FILES)
> -
>  # Also test sub-register code-gen if LLVM has eBPF v3 processor support which
>  # contains both ALU32 and JMP32 instructions.
>  SUBREG_CODEGEN := $(shell echo "int cal(int a) { return a > 0; }" | \
> @@ -42,13 +39,17 @@ SUBREG_CODEGEN := $(shell echo "int cal(int a) { return a > 0; }" | \
>  			$(LLC) -mattr=+alu32 -mcpu=v3 2>&1 | \
>  			grep 'if w')
>  ifneq ($(SUBREG_CODEGEN),)
> -TEST_GEN_FILES += $(patsubst %.o,alu32/%.o, $(BPF_OBJ_FILES))
> +TEST_GEN_PROGS += test_progs-alu32
>  endif
>  
> +# Also test bpf-gcc, if present
>  ifneq ($(BPF_GCC),)
> -TEST_GEN_FILES += $(patsubst %.o,bpf_gcc/%.o, $(BPF_OBJ_FILES))
> +TEST_GEN_PROGS += test_progs-bpf_gcc
>  endif
>  
> +TEST_GEN_FILES =
> +TEST_FILES =
> +
>  # Order correspond to 'make run_tests' order
>  TEST_PROGS := test_kmod.sh \
>  	test_libbpf.sh \
> @@ -82,6 +83,8 @@ TEST_GEN_PROGS_EXTENDED = test_libbpf_open test_sock_addr test_skb_cgroup_id_use
>  	flow_dissector_load test_flow_dissector test_tcp_check_syncookie_user \
>  	test_lirc_mode2_user
>  
> +TEST_CUSTOM_PROGS = urandom_read
> +
>  include ../lib.mk
>  
>  # Define simple and short `make test_progs`, `make test_sysctl`, etc targets
> @@ -94,21 +97,12 @@ $(notdir $(TEST_GEN_PROGS)						\
>  	 $(TEST_GEN_PROGS_EXTENDED)					\
>  	 $(TEST_CUSTOM_PROGS)): %: $(OUTPUT)/% ;
>  
> -# NOTE: $(OUTPUT) won't get default value if used before lib.mk
> -TEST_CUSTOM_PROGS = $(OUTPUT)/urandom_read
> -all: $(TEST_CUSTOM_PROGS)
> -
> -$(OUTPUT)/urandom_read: $(OUTPUT)/%: %.c
> +$(OUTPUT)/urandom_read: urandom_read.c
>  	$(CC) -o $@ $< -Wl,--build-id
>  
> -$(OUTPUT)/test_stub.o: test_stub.c
> -	$(CC) $(TEST_PROGS_CFLAGS) $(CFLAGS) -c -o $@ $<
> -
>  BPFOBJ := $(OUTPUT)/libbpf.a
>  
> -$(TEST_GEN_PROGS): $(OUTPUT)/test_stub.o $(BPFOBJ)
> -
> -$(TEST_GEN_PROGS_EXTENDED): $(OUTPUT)/test_stub.o $(OUTPUT)/libbpf.a
> +$(TEST_GEN_PROGS) $(TEST_GEN_PROGS_EXTENDED): $(OUTPUT)/test_stub.o $(BPFOBJ)
>  
>  $(OUTPUT)/test_dev_cgroup: cgroup_helpers.c
>  $(OUTPUT)/test_skb_cgroup_id_user: cgroup_helpers.c
> @@ -118,7 +112,6 @@ $(OUTPUT)/test_socket_cookie: cgroup_helpers.c
>  $(OUTPUT)/test_sockmap: cgroup_helpers.c
>  $(OUTPUT)/test_tcpbpf_user: cgroup_helpers.c
>  $(OUTPUT)/test_tcpnotify_user: cgroup_helpers.c trace_helpers.c
> -$(OUTPUT)/test_progs: cgroup_helpers.c trace_helpers.c
>  $(OUTPUT)/get_cgroup_id_user: cgroup_helpers.c
>  $(OUTPUT)/test_cgroup_storage: cgroup_helpers.c
>  $(OUTPUT)/test_netcnt: cgroup_helpers.c
> @@ -134,6 +127,10 @@ force:
>  $(BPFOBJ): force
>  	$(MAKE) -C $(BPFDIR) OUTPUT=$(OUTPUT)/
>  
> +BPF_HELPERS := $(BPFDIR)/bpf_helper_defs.h $(wildcard $(BPFDIR)/bpf_*.h)
> +$(BPFDIR)/bpf_helper_defs.h:
> +	$(MAKE) -C $(BPFDIR) OUTPUT=$(OUTPUT)/ bpf_helper_defs.h
> +
>  # Get Clang's default includes on this system, as opposed to those seen by
>  # '-target bpf'. This fixes "missing" files on some architectures/distros,
>  # such as asm/byteorder.h, asm/socket.h, asm/sockios.h, sys/cdefs.h etc.
> @@ -144,10 +141,11 @@ define get_sys_includes
>  $(shell $(1) -v -E - </dev/null 2>&1 \
>  	| sed -n '/<...> search starts here:/,/End of search list./{ s| \(/.*\)|-idirafter \1|p }')
>  endef
> +
>  CLANG_SYS_INCLUDES = $(call get_sys_includes,$(CLANG))
>  BPF_CFLAGS = -g -D__TARGET_ARCH_$(SRCARCH) 				\
> -	     -I. -I./include/uapi -I../../../include/uapi 		\
> -	     -I$(BPFDIR) -I$(OUTPUT)/../usr/include
> +	     -I. -I./include/uapi -I$(APIDIR)				\
> +	     -I$(BPFDIR) -I$(abspath $(OUTPUT)/../usr/include)
>  
>  CLANG_CFLAGS = $(CLANG_SYS_INCLUDES) \
>  	       -Wno-compare-distinct-pointer-types
> @@ -159,127 +157,170 @@ $(OUTPUT)/test_queue_map.o: test_queue_stack_map.h
>  $(OUTPUT)/test_stack_map.o: test_queue_stack_map.h
>  
>  $(OUTPUT)/flow_dissector_load.o: flow_dissector_load.h
> -$(OUTPUT)/test_progs.o: flow_dissector_load.h
>  
> -TEST_PROGS_CFLAGS := -I. -I$(OUTPUT)
> -TEST_MAPS_CFLAGS := -I. -I$(OUTPUT)
> -TEST_VERIFIER_CFLAGS := -I. -I$(OUTPUT) -Iverifier
> +# Build BPF object using Clang
> +# $1 - input .c file
> +# $2 - output .o file
> +# $3 - CFLAGS
> +# $4 - LDFLAGS
> +define CLANG_BPF_BUILD_RULE
> +	($(CLANG) $3 -O2 -target bpf -emit-llvm				\
> +		-c $1 -o - || echo "BPF obj compilation failed") | 	\
> +	$(LLC) -march=bpf -mcpu=probe $4 -filetype=obj -o $2
> +endef
> +# Similar to CLANG_BPF_BUILD_RULE, but using native Clang and bpf LLC
> +define CLANG_NATIVE_BPF_BUILD_RULE
> +	($(CLANG) $3 -O2 -emit-llvm					\
> +		-c $1 -o - || echo "BPF obj compilation failed") | 	\
> +	$(LLC) -march=bpf -mcpu=probe $4 -filetype=obj -o $2
> +endef
> +# Build BPF object using GCC
> +define GCC_BPF_BUILD_RULE
> +	$(BPF_GCC) $3 $4 -O2 -c $1 -o $2
> +endef
> +
> +# Set up extra TRUNNER_XXX "temporary" variables in the environment (relies on
> +# $eval()) and pass control to DEFINE_TEST_RUNNER_RULES.
> +# Parameters:
> +# $1 - test runner base binary name (e.g., test_progs)
> +# $2 - test runner extra "flavor" (e.g., alu32, gcc-bpf, etc)
> +define DEFINE_TEST_RUNNER
> +
> +TRUNNER_OUTPUT := $(OUTPUT)$(if $2,/)$2
> +TRUNNER_BINARY := $1$(if $2,-)$2
> +TRUNNER_TEST_OBJS := $$(patsubst %.c,$$(TRUNNER_OUTPUT)/%.test.o,	\
> +				 $$(notdir $$(wildcard $(TRUNNER_TESTS_DIR)/*.c)))
> +TRUNNER_EXTRA_OBJS := $$(patsubst %.c,$$(TRUNNER_OUTPUT)/%.o,		\
> +				 $$(filter %.c,$(TRUNNER_EXTRA_SOURCES)))
> +TRUNNER_EXTRA_HDRS := $$(filter %.h,$(TRUNNER_EXTRA_SOURCES))
> +TRUNNER_TESTS_HDR := $(TRUNNER_TESTS_DIR)/tests.h
> +TRUNNER_BPF_OBJS := $$(patsubst %.c,$$(TRUNNER_OUTPUT)/%.o,		\
> +				$$(notdir $$(wildcard $(TRUNNER_BPF_PROGS_DIR)/*.c)))
> +
> +# Evaluate rules now with extra TRUNNER_XXX variables above already defined
> +$$(eval $$(call DEFINE_TEST_RUNNER_RULES,$1,$2))
> +
> +endef
> +
> +# Using TRUNNER_XXX variables, provided by callers of DEFINE_TEST_RUNNER and
> +# set up by DEFINE_TEST_RUNNER itself, create test runner build rules with:
> +# $1 - test runner base binary name (e.g., test_progs)
> +# $2 - test runner extra "flavor" (e.g., alu32, gcc-bpf, etc)
> +define DEFINE_TEST_RUNNER_RULES
>  
> +ifeq ($($(TRUNNER_OUTPUT)-dir),)
> +$(TRUNNER_OUTPUT)-dir := y
> +$(TRUNNER_OUTPUT):
> +	mkdir -p $$@
> +endif
> +
> +# ensure we set up BPF objects generation rule just once for a given
> +# input/output directory combination
> +ifeq ($($(TRUNNER_BPF_PROGS_DIR)$(if $2,-)$2-bpfobjs),)
> +$(TRUNNER_BPF_PROGS_DIR)$(if $2,-)$2-bpfobjs := y
> +$(TRUNNER_BPF_OBJS): $(TRUNNER_OUTPUT)/%.o:				\
> +		     $(TRUNNER_BPF_PROGS_DIR)/%.c			\
> +		     $(TRUNNER_BPF_PROGS_DIR)/*.h			\
> +		     $$(BPF_HELPERS) | $(TRUNNER_OUTPUT)
> +	$$(call $(TRUNNER_BPF_BUILD_RULE),$$<,$$@,			\
> +					  $(TRUNNER_BPF_CFLAGS),	\
> +					  $(TRUNNER_BPF_LDFLAGS))
> +endif
> +
> +# ensure we set up tests.h header generation rule just once
> +ifeq ($($(TRUNNER_TESTS_DIR)-tests-hdr),)
> +$(TRUNNER_TESTS_DIR)-tests-hdr := y
> +$(TRUNNER_TESTS_HDR): $(TRUNNER_TESTS_DIR)/*.c
> +	$$(shell ( cd $(TRUNNER_TESTS_DIR);				\
> +		  echo '/* Generated header, do not edit */';		\
> +		  ls *.c 2> /dev/null |					\
> +			sed -e 's@\([^\.]*\)\.c@DEFINE_TEST(\1)@';	\
> +		 ) > $$@)
> +endif
> +
> +# compile individual test files
> +# Note: we cd into output directory to ensure embedded BPF object is found
> +$(TRUNNER_TEST_OBJS): $(TRUNNER_OUTPUT)/%.test.o:			\
> +		      $(TRUNNER_TESTS_DIR)/%.c				\
> +		      $(TRUNNER_EXTRA_HDRS)				\
> +		      $(TRUNNER_BPF_OBJS)				\
> +		      $$(BPFOBJ) | $(TRUNNER_OUTPUT)
> +	cd $$(@D) && $$(CC) $$(CFLAGS) $$(LDLIBS) -c $(CURDIR)/$$< -o $$(@F)
> +
> +$(TRUNNER_EXTRA_OBJS): $(TRUNNER_OUTPUT)/%.o:				\
> +		       %.c						\
> +		       $(TRUNNER_EXTRA_HDRS)				\
> +		       $(TRUNNER_TESTS_HDR)				\
> +		       $$(BPFOBJ) | $(TRUNNER_OUTPUT)
> +	$$(CC) $$(CFLAGS) $$(LDLIBS) -c $$< -o $$@
> +
> +$(TRUNNER_BINARY)-extras: $(TRUNNER_EXTRA_FILES) | $(TRUNNER_OUTPUT)
> +ifneq ($2,)
> +	# only copy extra resources if in flavored build
> +	cp -a $$^ $(TRUNNER_OUTPUT)/
> +endif
> +
> +$(OUTPUT)/$(TRUNNER_BINARY): $(TRUNNER_TEST_OBJS)			\
> +			     $(TRUNNER_EXTRA_OBJS) $$(BPFOBJ)		\
> +			     | $(TRUNNER_BINARY)-extras
> +	$$(CC) $$(CFLAGS) $$(LDLIBS) $$(filter %.a %.o,$$^) -o $$@
> +
> +endef
> +
> +# Define test_progs test runner.
> +TRUNNER_TESTS_DIR := prog_tests
> +TRUNNER_BPF_PROGS_DIR := progs
> +TRUNNER_EXTRA_SOURCES := test_progs.c cgroup_helpers.c trace_helpers.c	\
> +			 flow_dissector_load.h
> +TRUNNER_EXTRA_FILES := $(OUTPUT)/urandom_read				\
> +		       $(wildcard progs/btf_dump_test_case_*.c)
> +TRUNNER_BPF_BUILD_RULE := CLANG_BPF_BUILD_RULE
> +TRUNNER_BPF_CFLAGS := -I. -I$(OUTPUT) $(BPF_CFLAGS) $(CLANG_CFLAGS)
> +TRUNNER_BPF_LDFLAGS :=
> +$(eval $(call DEFINE_TEST_RUNNER,test_progs))
> +
> +# Define test_progs-alu32 test runner.
>  ifneq ($(SUBREG_CODEGEN),)
> -ALU32_BUILD_DIR = $(OUTPUT)/alu32
> -TEST_CUSTOM_PROGS += $(ALU32_BUILD_DIR)/test_progs_32
> -$(ALU32_BUILD_DIR):
> -	mkdir -p $@
> -
> -$(ALU32_BUILD_DIR)/urandom_read: $(OUTPUT)/urandom_read | $(ALU32_BUILD_DIR)
> -	cp $< $@
> -
> -$(ALU32_BUILD_DIR)/test_progs_32: test_progs.c $(OUTPUT)/libbpf.a\
> -						$(ALU32_BUILD_DIR)/urandom_read \
> -						| $(ALU32_BUILD_DIR)
> -	$(CC) $(TEST_PROGS_CFLAGS) $(CFLAGS) \
> -		-o $(ALU32_BUILD_DIR)/test_progs_32 \
> -		test_progs.c test_stub.c cgroup_helpers.c trace_helpers.c prog_tests/*.c \
> -		$(OUTPUT)/libbpf.a $(LDLIBS)
> -
> -$(ALU32_BUILD_DIR)/test_progs_32: $(PROG_TESTS_H)
> -$(ALU32_BUILD_DIR)/test_progs_32: prog_tests/*.c
> -
> -$(ALU32_BUILD_DIR)/%.o: progs/%.c $(ALU32_BUILD_DIR)/test_progs_32 \
> -					| $(ALU32_BUILD_DIR)
> -	($(CLANG) $(BPF_CFLAGS) $(CLANG_CFLAGS) -O2 -target bpf -emit-llvm \
> -		-c $< -o - || echo "clang failed") | \
> -	$(LLC) -march=bpf -mcpu=probe -mattr=+alu32 $(LLC_FLAGS) \
> -		-filetype=obj -o $@
> +TRUNNER_BPF_LDFLAGS += -mattr=+alu32
> +$(eval $(call DEFINE_TEST_RUNNER,test_progs,alu32))
>  endif
>  
> +# Define test_progs BPF-GCC-flavored test runner.
>  ifneq ($(BPF_GCC),)
> -GCC_SYS_INCLUDES = $(call get_sys_includes,gcc)
>  IS_LITTLE_ENDIAN = $(shell $(CC) -dM -E - </dev/null | \
>  			grep 'define __BYTE_ORDER__ __ORDER_LITTLE_ENDIAN__')
> -ifeq ($(IS_LITTLE_ENDIAN),)
> -MENDIAN=-mbig-endian
> -else
> -MENDIAN=-mlittle-endian
> -endif
> -BPF_GCC_CFLAGS = $(GCC_SYS_INCLUDES) $(MENDIAN)
> -BPF_GCC_BUILD_DIR = $(OUTPUT)/bpf_gcc
> -TEST_CUSTOM_PROGS += $(BPF_GCC_BUILD_DIR)/test_progs_bpf_gcc
> -$(BPF_GCC_BUILD_DIR):
> -	mkdir -p $@
> -
> -$(BPF_GCC_BUILD_DIR)/urandom_read: $(OUTPUT)/urandom_read | $(BPF_GCC_BUILD_DIR)
> -	cp $< $@
> -
> -$(BPF_GCC_BUILD_DIR)/test_progs_bpf_gcc: $(OUTPUT)/test_progs \
> -					 | $(BPF_GCC_BUILD_DIR)
> -	cp $< $@
> -
> -$(BPF_GCC_BUILD_DIR)/%.o: progs/%.c $(BPF_GCC_BUILD_DIR)/test_progs_bpf_gcc \
> -			  | $(BPF_GCC_BUILD_DIR)
> -	$(BPF_GCC) $(BPF_CFLAGS) $(BPF_GCC_CFLAGS) -O2 -c $< -o $@
> +MENDIAN=$(if $(IS_LITTLE_ENDIAN),-mlittle-endian,-mbig-endian)
> +
> +TRUNNER_BPF_BUILD_RULE := GCC_BPF_BUILD_RULE
> +TRUNNER_BPF_CFLAGS := $(BPF_CFLAGS) $(call get_sys_includes,gcc) $(MENDIAN)
> +TRUNNER_BPF_LDFLAGS :=
> +$(eval $(call DEFINE_TEST_RUNNER,test_progs,bpf_gcc))
>  endif
>  
> -# Have one program compiled without "-target bpf" to test whether libbpf loads
> -# it successfully
> -$(OUTPUT)/test_xdp.o: progs/test_xdp.c
> -	($(CLANG) $(BPF_CFLAGS) $(CLANG_CFLAGS) -O2 -emit-llvm -c $< -o - || \
> -		echo "clang failed") | \
> -	$(LLC) -march=bpf -mcpu=probe $(LLC_FLAGS) -filetype=obj -o $@
> -
> -# libbpf has to be built before BPF programs due to bpf_helper_defs.h
> -$(OUTPUT)/%.o: progs/%.c | $(BPFOBJ)
> -	($(CLANG) $(BPF_CFLAGS) $(CLANG_CFLAGS) -O2 -target bpf -emit-llvm \
> -		-c $< -o - || echo "clang failed") | \
> -	$(LLC) -march=bpf -mcpu=probe $(LLC_FLAGS) -filetype=obj -o $@
> -
> -PROG_TESTS_DIR = $(OUTPUT)/prog_tests
> -$(PROG_TESTS_DIR):
> -	mkdir -p $@
> -PROG_TESTS_H := $(PROG_TESTS_DIR)/tests.h
> -PROG_TESTS_FILES := $(wildcard prog_tests/*.c)
> -test_progs.c: $(PROG_TESTS_H)
> -$(OUTPUT)/test_progs: CFLAGS += $(TEST_PROGS_CFLAGS)
> -$(OUTPUT)/test_progs: test_progs.c $(PROG_TESTS_FILES) | $(OUTPUT)/test_attach_probe.o $(PROG_TESTS_H)
> -$(PROG_TESTS_H): $(PROG_TESTS_FILES) | $(PROG_TESTS_DIR)
> -	$(shell ( cd prog_tests/; \
> -		  echo '/* Generated header, do not edit */'; \
> -		  ls *.c 2> /dev/null | \
> -			sed -e 's@\([^\.]*\)\.c@DEFINE_TEST(\1)@'; \
> -		 ) > $(PROG_TESTS_H))
> -
> -MAP_TESTS_DIR = $(OUTPUT)/map_tests
> -$(MAP_TESTS_DIR):
> -	mkdir -p $@
> -MAP_TESTS_H := $(MAP_TESTS_DIR)/tests.h
> -MAP_TESTS_FILES := $(wildcard map_tests/*.c)
> -test_maps.c: $(MAP_TESTS_H)
> -$(OUTPUT)/test_maps: CFLAGS += $(TEST_MAPS_CFLAGS)
> -$(OUTPUT)/test_maps: test_maps.c $(MAP_TESTS_FILES) | $(MAP_TESTS_H)
> -$(MAP_TESTS_H): $(MAP_TESTS_FILES) | $(MAP_TESTS_DIR)
> -	$(shell ( cd map_tests/; \
> -		  echo '/* Generated header, do not edit */'; \
> -		  ls *.c 2> /dev/null | \
> -			sed -e 's@\([^\.]*\)\.c@DEFINE_TEST(\1)@'; \
> -		 ) > $(MAP_TESTS_H))
> -
> -VERIFIER_TESTS_DIR = $(OUTPUT)/verifier
> -$(VERIFIER_TESTS_DIR):
> -	mkdir -p $@
> -VERIFIER_TESTS_H := $(VERIFIER_TESTS_DIR)/tests.h
> -VERIFIER_TEST_FILES := $(wildcard verifier/*.c)
> -test_verifier.c: $(VERIFIER_TESTS_H)
> -$(OUTPUT)/test_verifier: CFLAGS += $(TEST_VERIFIER_CFLAGS)
> -$(OUTPUT)/test_verifier: test_verifier.c | $(VERIFIER_TEST_FILES) $(VERIFIER_TESTS_H)
> -$(VERIFIER_TESTS_H): $(VERIFIER_TEST_FILES) | $(VERIFIER_TESTS_DIR)
> +# Define test_maps test runner.
> +TRUNNER_TESTS_DIR := map_tests
> +TRUNNER_BPF_PROGS_DIR := progs
> +TRUNNER_EXTRA_SOURCES := test_maps.c
> +TRUNNER_EXTRA_FILES :=
> +TRUNNER_BPF_BUILD_RULE := $$(error no BPF objects should be built)
> +TRUNNER_BPF_CFLAGS :=
> +TRUNNER_BPF_LDFLAGS :=
> +$(eval $(call DEFINE_TEST_RUNNER,test_maps))
> +
> +# Define test_verifier test runner.
> +# It is much simpler than test_maps/test_progs and sufficiently different from
> +# them (e.g., test.h is using completely pattern), that it's worth just
> +# explicitly defining all the rules explicitly.
> +verifier/tests.h: verifier/*.c
>  	$(shell ( cd verifier/; \
>  		  echo '/* Generated header, do not edit */'; \
>  		  echo '#ifdef FILL_ARRAY'; \
> -		  ls *.c 2> /dev/null | \
> -			sed -e 's@\(.*\)@#include \"\1\"@'; \
> +		  ls *.c 2> /dev/null | sed -e 's@\(.*\)@#include \"\1\"@'; \
>  		  echo '#endif' \
> -		 ) > $(VERIFIER_TESTS_H))
> +		) > verifier/tests.h)
> +$(OUTPUT)/test_verifier: test_verifier.c verifier/tests.h $(BPFOBJ) | $(OUTPUT)
> +	$(CC) $(CFLAGS) $(LDLIBS) $(filter %.a %.o %.c,$^) -o $@
>  
> -EXTRA_CLEAN := $(TEST_CUSTOM_PROGS) $(ALU32_BUILD_DIR) $(BPF_GCC_BUILD_DIR) \
> -	$(VERIFIER_TESTS_H) $(PROG_TESTS_H) $(MAP_TESTS_H) \
> -	feature
> +EXTRA_CLEAN := $(TEST_CUSTOM_PROGS)					\
> +	prog_tests/tests.h map_tests/tests.h verifier/tests.h		\
> +	feature $(OUTPUT)/*.o $(OUTPUT)/alu32 $(OUTPUT)/bpf_gcc
> -- 
> 2.17.1
>