samples/bpf/Makefile - linux - Git at Google

 # SPDX-License-Identifier: GPL-2.0

 BPF_SAMPLES_PATH ?= $(abspath $(src))
 TOOLS_PATH := $(BPF_SAMPLES_PATH)/../../tools

 pound := \#

 # List of programs to build
 tprogs-y := test_lru_dist
 tprogs-y += sock_example
 tprogs-y += fds_example
 tprogs-y += sockex1
 tprogs-y += sockex2
 tprogs-y += sockex3
 tprogs-y += tracex1
 tprogs-y += tracex2
 tprogs-y += tracex3
 tprogs-y += tracex4
 tprogs-y += tracex5
 tprogs-y += tracex6
 tprogs-y += tracex7
 tprogs-y += test_probe_write_user
 tprogs-y += trace_output
 tprogs-y += lathist
 tprogs-y += offwaketime
 tprogs-y += spintest
 tprogs-y += map_perf_test
 tprogs-y += test_overhead
 tprogs-y += test_cgrp2_array_pin
 tprogs-y += test_cgrp2_attach
 tprogs-y += test_cgrp2_sock
 tprogs-y += test_cgrp2_sock2
 tprogs-y += xdp_router_ipv4
 tprogs-y += test_current_task_under_cgroup
 tprogs-y += trace_event
 tprogs-y += sampleip
 tprogs-y += tc_l2_redirect
 tprogs-y += lwt_len_hist
 tprogs-y += xdp_tx_iptunnel
 tprogs-y += test_map_in_map
 tprogs-y += per_socket_stats_example
 tprogs-y += syscall_tp
 tprogs-y += cpustat
 tprogs-y += xdp_adjust_tail
 tprogs-y += xdp_fwd
 tprogs-y += task_fd_query
 tprogs-y += ibumad
 tprogs-y += hbm

 # Libbpf dependencies
 LIBBPF_SRC = $(TOOLS_PATH)/lib/bpf
 LIBBPF_OUTPUT = $(abspath $(BPF_SAMPLES_PATH))/libbpf
 LIBBPF_DESTDIR = $(LIBBPF_OUTPUT)
 LIBBPF_INCLUDE = $(LIBBPF_DESTDIR)/include
 LIBBPF = $(LIBBPF_OUTPUT)/libbpf.a

 CGROUP_HELPERS := ../../tools/testing/selftests/bpf/cgroup_helpers.o
 TRACE_HELPERS := ../../tools/testing/selftests/bpf/trace_helpers.o
 XDP_SAMPLE := xdp_sample_user.o

 fds_example-objs := fds_example.o
 sockex1-objs := sockex1_user.o
 sockex2-objs := sockex2_user.o
 sockex3-objs := sockex3_user.o
 tracex1-objs := tracex1_user.o $(TRACE_HELPERS)
 tracex2-objs := tracex2_user.o
 tracex3-objs := tracex3_user.o
 tracex4-objs := tracex4_user.o
 tracex5-objs := tracex5_user.o $(TRACE_HELPERS)
 tracex6-objs := tracex6_user.o
 tracex7-objs := tracex7_user.o
 test_probe_write_user-objs := test_probe_write_user_user.o
 trace_output-objs := trace_output_user.o
 lathist-objs := lathist_user.o
 offwaketime-objs := offwaketime_user.o $(TRACE_HELPERS)
 spintest-objs := spintest_user.o $(TRACE_HELPERS)
 map_perf_test-objs := map_perf_test_user.o
 test_overhead-objs := test_overhead_user.o
 test_cgrp2_array_pin-objs := test_cgrp2_array_pin.o
 test_cgrp2_attach-objs := test_cgrp2_attach.o
 test_cgrp2_sock-objs := test_cgrp2_sock.o
 test_cgrp2_sock2-objs := test_cgrp2_sock2.o
 test_current_task_under_cgroup-objs := $(CGROUP_HELPERS) \
 				       test_current_task_under_cgroup_user.o
 trace_event-objs := trace_event_user.o $(TRACE_HELPERS)
 sampleip-objs := sampleip_user.o $(TRACE_HELPERS)
 tc_l2_redirect-objs := tc_l2_redirect_user.o
 lwt_len_hist-objs := lwt_len_hist_user.o
 xdp_tx_iptunnel-objs := xdp_tx_iptunnel_user.o
 test_map_in_map-objs := test_map_in_map_user.o
 per_socket_stats_example-objs := cookie_uid_helper_example.o
 syscall_tp-objs := syscall_tp_user.o
 cpustat-objs := cpustat_user.o
 xdp_adjust_tail-objs := xdp_adjust_tail_user.o
 xdp_fwd-objs := xdp_fwd_user.o
 task_fd_query-objs := task_fd_query_user.o $(TRACE_HELPERS)
 ibumad-objs := ibumad_user.o
 hbm-objs := hbm.o $(CGROUP_HELPERS)

 xdp_router_ipv4-objs := xdp_router_ipv4_user.o $(XDP_SAMPLE)

 # Tell kbuild to always build the programs
 always-y := $(tprogs-y)
 always-y += sockex1_kern.o
 always-y += sockex2_kern.o
 always-y += sockex3_kern.o
 always-y += tracex1.bpf.o
 always-y += tracex2.bpf.o
 always-y += tracex3.bpf.o
 always-y += tracex4.bpf.o
 always-y += tracex5.bpf.o
 always-y += tracex6.bpf.o
 always-y += tracex7.bpf.o
 always-y += sock_flags.bpf.o
 always-y += test_probe_write_user.bpf.o
 always-y += trace_output.bpf.o
 always-y += tcbpf1_kern.o
 always-y += tc_l2_redirect_kern.o
 always-y += lathist_kern.o
 always-y += offwaketime.bpf.o
 always-y += spintest.bpf.o
 always-y += map_perf_test.bpf.o
 always-y += test_overhead_tp.bpf.o
 always-y += test_overhead_raw_tp.bpf.o
 always-y += test_overhead_kprobe.bpf.o
 always-y += parse_varlen.o parse_simple.o parse_ldabs.o
 always-y += test_cgrp2_tc.bpf.o
 always-y += test_current_task_under_cgroup.bpf.o
 always-y += trace_event_kern.o
 always-y += sampleip_kern.o
 always-y += lwt_len_hist.bpf.o
 always-y += xdp_tx_iptunnel_kern.o
 always-y += test_map_in_map.bpf.o
 always-y += tcp_synrto_kern.o
 always-y += tcp_rwnd_kern.o
 always-y += tcp_bufs_kern.o
 always-y += tcp_cong_kern.o
 always-y += tcp_iw_kern.o
 always-y += tcp_clamp_kern.o
 always-y += tcp_basertt_kern.o
 always-y += tcp_tos_reflect_kern.o
 always-y += tcp_dumpstats_kern.o
 always-y += xdp2skb_meta_kern.o
 always-y += syscall_tp_kern.o
 always-y += cpustat_kern.o
 always-y += xdp_adjust_tail_kern.o
 always-y += xdp_fwd_kern.o
 always-y += task_fd_query_kern.o
 always-y += ibumad_kern.o
 always-y += hbm_out_kern.o
 always-y += hbm_edt_kern.o

 TPROGS_CFLAGS = $(TPROGS_USER_CFLAGS)
 TPROGS_LDFLAGS = $(TPROGS_USER_LDFLAGS)

 ifeq ($(ARCH), arm)
 # Strip all except -D__LINUX_ARM_ARCH__ option needed to handle linux
 # headers when arm instruction set identification is requested.
 ARM_ARCH_SELECTOR := $(filter -D__LINUX_ARM_ARCH__%, $(KBUILD_CFLAGS))
 BPF_EXTRA_CFLAGS := $(ARM_ARCH_SELECTOR)
 TPROGS_CFLAGS += $(ARM_ARCH_SELECTOR)
 endif

 ifeq ($(ARCH), mips)
 TPROGS_CFLAGS += -D__SANE_USERSPACE_TYPES__
 ifdef CONFIG_MACH_LOONGSON64
 BPF_EXTRA_CFLAGS += -I$(srctree)/arch/mips/include/asm/mach-loongson64
 BPF_EXTRA_CFLAGS += -I$(srctree)/arch/mips/include/asm/mach-generic
 endif
 endif

 TPROGS_CFLAGS += -Wall -O2
 TPROGS_CFLAGS += -Wmissing-prototypes
 TPROGS_CFLAGS += -Wstrict-prototypes
 TPROGS_CFLAGS += $(call try-run,\
 	printf "int main() { return 0; }" |\
 	$(CC) -Werror -fsanitize=bounds -x c - -o "$$TMP",-fsanitize=bounds,)

 TPROGS_CFLAGS += -I$(objtree)/usr/include
 TPROGS_CFLAGS += -I$(srctree)/tools/testing/selftests/bpf/
 TPROGS_CFLAGS += -I$(LIBBPF_INCLUDE)
 TPROGS_CFLAGS += -I$(srctree)/tools/include
 TPROGS_CFLAGS += -I$(srctree)/tools/perf
 TPROGS_CFLAGS += -I$(srctree)/tools/lib
 TPROGS_CFLAGS += -DHAVE_ATTR_TEST=0

 ifdef SYSROOT
 TPROGS_CFLAGS += --sysroot=$(SYSROOT)
 TPROGS_LDFLAGS := -L$(SYSROOT)/usr/lib
 endif

 TPROGS_LDLIBS			+= $(LIBBPF) -lelf -lz
 TPROGLDLIBS_xdp_router_ipv4	+= -lm -pthread
 TPROGLDLIBS_tracex4		+= -lrt
 TPROGLDLIBS_trace_output	+= -lrt
 TPROGLDLIBS_map_perf_test	+= -lrt
 TPROGLDLIBS_test_overhead	+= -lrt

 # Allows pointing LLC/CLANG to a LLVM backend with bpf support, redefine on cmdline:
 # make M=samples/bpf LLC=~/git/llvm-project/llvm/build/bin/llc CLANG=~/git/llvm-project/llvm/build/bin/clang
 LLC ?= llc
 CLANG ?= clang
 OPT ?= opt
 LLVM_DIS ?= llvm-dis
 LLVM_OBJCOPY ?= llvm-objcopy
 LLVM_READELF ?= llvm-readelf
 BTF_PAHOLE ?= pahole

 # Detect that we're cross compiling and use the cross compiler
 ifdef CROSS_COMPILE
 CLANG_ARCH_ARGS = --target=$(notdir $(CROSS_COMPILE:%-=%))
 endif

 # Don't evaluate probes and warnings if we need to run make recursively
 ifneq ($(src),)
 HDR_PROBE := $(shell printf "$(pound)include <linux/types.h>\n struct list_head { int a; }; int main() { return 0; }" | \
 	$(CC) $(TPROGS_CFLAGS) $(TPROGS_LDFLAGS) -x c - \
 	-o /dev/null 2>/dev/null && echo okay)

 ifeq ($(HDR_PROBE),)
 $(warning WARNING: Detected possible issues with include path.)
 $(warning WARNING: Please install kernel headers locally (make headers_install).)
 endif

 BTF_LLC_PROBE := $(shell $(LLC) -march=bpf -mattr=help 2>&1 | grep dwarfris)
 BTF_PAHOLE_PROBE := $(shell $(BTF_PAHOLE) --help 2>&1 | grep BTF)
 BTF_OBJCOPY_PROBE := $(shell $(LLVM_OBJCOPY) --help 2>&1 | grep -i 'usage.*llvm')
 BTF_LLVM_PROBE := $(shell echo "int main() { return 0; }" | \
 			  $(CLANG) --target=bpf -O2 -g -c -x c - -o ./llvm_btf_verify.o; \
 			  $(LLVM_READELF) -S ./llvm_btf_verify.o | grep BTF; \
 			  /bin/rm -f ./llvm_btf_verify.o)

 BPF_EXTRA_CFLAGS += -fno-stack-protector
 ifneq ($(BTF_LLVM_PROBE),)
 	BPF_EXTRA_CFLAGS += -g
 else
 ifneq ($(and $(BTF_LLC_PROBE),$(BTF_PAHOLE_PROBE),$(BTF_OBJCOPY_PROBE)),)
 	BPF_EXTRA_CFLAGS += -g
 	LLC_FLAGS += -mattr=dwarfris
 	DWARF2BTF = y
 endif
 endif
 endif

 # Trick to allow make to be run from this directory
 all:
 	$(MAKE) -C ../../ M=$(CURDIR) BPF_SAMPLES_PATH=$(CURDIR)

 clean:
 	$(MAKE) -C ../../ M=$(CURDIR) clean
 	@find $(CURDIR) -type f -name '*~' -delete
 	@$(RM) -r $(CURDIR)/libbpf $(CURDIR)/bpftool

 $(LIBBPF): $(wildcard $(LIBBPF_SRC)/*.[ch] $(LIBBPF_SRC)/Makefile) | $(LIBBPF_OUTPUT)
 # Fix up variables inherited from Kbuild that tools/ build system won't like
 	$(MAKE) -C $(LIBBPF_SRC) RM='rm -rf' EXTRA_CFLAGS="$(TPROGS_CFLAGS)" \
 		LDFLAGS="$(TPROGS_LDFLAGS)" srctree=$(BPF_SAMPLES_PATH)/../../ \
 		O= OUTPUT=$(LIBBPF_OUTPUT)/ DESTDIR=$(LIBBPF_DESTDIR) prefix= \
 		$@ install_headers

 BPFTOOLDIR := $(TOOLS_PATH)/bpf/bpftool
 BPFTOOL_OUTPUT := $(abspath $(BPF_SAMPLES_PATH))/bpftool
 DEFAULT_BPFTOOL := $(BPFTOOL_OUTPUT)/bootstrap/bpftool
 BPFTOOL ?= $(DEFAULT_BPFTOOL)
 $(DEFAULT_BPFTOOL): $(wildcard $(BPFTOOLDIR)/*.[ch] $(BPFTOOLDIR)/Makefile) | $(BPFTOOL_OUTPUT)
 	$(MAKE) -C $(BPFTOOLDIR) srctree=$(BPF_SAMPLES_PATH)/../../ 		\
 		OUTPUT=$(BPFTOOL_OUTPUT)/ bootstrap

 $(LIBBPF_OUTPUT) $(BPFTOOL_OUTPUT):
 	$(call msg,MKDIR,$@)
 	$(Q)mkdir -p $@

 $(obj)/syscall_nrs.h:	$(obj)/syscall_nrs.s FORCE
 	$(call filechk,offsets,__SYSCALL_NRS_H__)

 targets += syscall_nrs.s
 clean-files += syscall_nrs.h

 FORCE:


 # Verify LLVM compiler tools are available and bpf target is supported by llc
 .PHONY: verify_cmds verify_target_bpf $(CLANG) $(LLC)

 verify_cmds: $(CLANG) $(LLC)
 	@for TOOL in $^ ; do \
 		if ! (which -- "$${TOOL}" > /dev/null 2>&1); then \
 			echo "*** ERROR: Cannot find LLVM tool $${TOOL}" ;\
 			exit 1; \
 		else true; fi; \
 	done

 verify_target_bpf: verify_cmds
 	@if ! (${LLC} -march=bpf -mattr=help > /dev/null 2>&1); then \
 		echo "*** ERROR: LLVM (${LLC}) does not support 'bpf' target" ;\
 		echo "   NOTICE: LLVM version >= 3.7.1 required" ;\
 		exit 2; \
 	else true; fi

 $(BPF_SAMPLES_PATH)/*.c: verify_target_bpf $(LIBBPF)
 $(src)/*.c: verify_target_bpf $(LIBBPF)

 libbpf_hdrs: $(LIBBPF)
 $(obj)/$(TRACE_HELPERS) $(obj)/$(CGROUP_HELPERS) $(obj)/$(XDP_SAMPLE): | libbpf_hdrs

 .PHONY: libbpf_hdrs

 $(obj)/xdp_router_ipv4_user.o: $(obj)/xdp_router_ipv4.skel.h

 $(obj)/tracex5.bpf.o: $(obj)/syscall_nrs.h
 $(obj)/hbm_out_kern.o: $(src)/hbm.h $(src)/hbm_kern.h
 $(obj)/hbm.o: $(src)/hbm.h
 $(obj)/hbm_edt_kern.o: $(src)/hbm.h $(src)/hbm_kern.h

 # Override includes for xdp_sample_user.o because $(srctree)/usr/include in
 # TPROGS_CFLAGS causes conflicts
 XDP_SAMPLE_CFLAGS += -Wall -O2 \
 		     -I$(src)/../../tools/include \
 		     -I$(src)/../../tools/include/uapi \
 		     -I$(LIBBPF_INCLUDE) \
 		     -I$(src)/../../tools/testing/selftests/bpf

 $(obj)/$(XDP_SAMPLE): TPROGS_CFLAGS = $(XDP_SAMPLE_CFLAGS) $(TPROGS_USER_CFLAGS)
 $(obj)/$(XDP_SAMPLE): $(src)/xdp_sample_user.h $(src)/xdp_sample_shared.h
 # Override includes for trace_helpers.o because __must_check won't be defined
 # in our include path.
 $(obj)/$(TRACE_HELPERS): TPROGS_CFLAGS := $(TPROGS_CFLAGS) -D__must_check=

 -include $(BPF_SAMPLES_PATH)/Makefile.target

 VMLINUX_BTF_PATHS ?= $(abspath $(if $(O),$(O)/vmlinux))				\
 		     $(abspath $(if $(KBUILD_OUTPUT),$(KBUILD_OUTPUT)/vmlinux))	\
 		     $(abspath ./vmlinux)
 VMLINUX_BTF ?= $(abspath $(firstword $(wildcard $(VMLINUX_BTF_PATHS))))

 $(obj)/vmlinux.h: $(VMLINUX_BTF) $(BPFTOOL)
 ifeq ($(VMLINUX_H),)
 ifeq ($(VMLINUX_BTF),)
 	$(error Cannot find a vmlinux for VMLINUX_BTF at any of "$(VMLINUX_BTF_PATHS)",\
 		build the kernel or set VMLINUX_BTF like "VMLINUX_BTF=/sys/kernel/btf/vmlinux" or VMLINUX_H variable)
 endif
 	$(Q)$(BPFTOOL) btf dump file $(VMLINUX_BTF) format c > $@
 else
 	$(Q)cp "$(VMLINUX_H)" $@
 endif

 clean-files += vmlinux.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.
 #
 # Use '-idirafter': Don't interfere with include mechanics except where the
 # build would have failed anyways.
 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 }') \
 $(shell $(1) -dM -E - </dev/null | grep '#define __riscv_xlen ' | sed 's/#define /-D/' | sed 's/ /=/')
 endef

 CLANG_SYS_INCLUDES = $(call get_sys_includes,$(CLANG))

 $(obj)/xdp_router_ipv4.bpf.o: $(obj)/xdp_sample.bpf.o

 $(obj)/%.bpf.o: $(src)/%.bpf.c $(obj)/vmlinux.h $(src)/xdp_sample.bpf.h $(src)/xdp_sample_shared.h
 	@echo "  CLANG-BPF " $@
 	$(Q)$(CLANG) -g -O2 --target=bpf -D__TARGET_ARCH_$(SRCARCH) \
 		-Wno-compare-distinct-pointer-types -I$(srctree)/include \
 		-I$(srctree)/samples/bpf -I$(srctree)/tools/include \
 		-I$(LIBBPF_INCLUDE) $(CLANG_SYS_INCLUDES) \
 		-c $(filter %.bpf.c,$^) -o $@

 LINKED_SKELS := xdp_router_ipv4.skel.h
 clean-files += $(LINKED_SKELS)

 xdp_router_ipv4.skel.h-deps := xdp_router_ipv4.bpf.o xdp_sample.bpf.o

 LINKED_BPF_SRCS := $(patsubst %.bpf.o,%.bpf.c,$(foreach skel,$(LINKED_SKELS),$($(skel)-deps)))

 BPF_SRCS_LINKED := $(notdir $(wildcard $(src)/*.bpf.c))
 BPF_OBJS_LINKED := $(patsubst %.bpf.c,$(obj)/%.bpf.o, $(BPF_SRCS_LINKED))
 BPF_SKELS_LINKED := $(addprefix $(obj)/,$(LINKED_SKELS))

 $(BPF_SKELS_LINKED): $(BPF_OBJS_LINKED) $(BPFTOOL)
 	@echo "  BPF GEN-OBJ " $(@:.skel.h=)
 	$(Q)$(BPFTOOL) gen object $(@:.skel.h=.lbpf.o) $(addprefix $(obj)/,$($(@F)-deps))
 	@echo "  BPF GEN-SKEL" $(@:.skel.h=)
 	$(Q)$(BPFTOOL) gen skeleton $(@:.skel.h=.lbpf.o) name $(notdir $(@:.skel.h=)) > $@

 # asm/sysreg.h - inline assembly used by it is incompatible with llvm.
 # But, there is no easy way to fix it, so just exclude it since it is
 # useless for BPF samples.
 # below we use long chain of commands, clang | opt | llvm-dis | llc,
 # to generate final object file. 'clang' compiles the source into IR
 # with native target, e.g., x64, arm64, etc. 'opt' does bpf CORE IR builtin
 # processing (llvm12) and IR optimizations. 'llvm-dis' converts
 # 'opt' output to IR, and finally 'llc' generates bpf byte code.
 $(obj)/%.o: $(src)/%.c
 	@echo "  CLANG-bpf " $@
 	$(Q)$(CLANG) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(BPF_EXTRA_CFLAGS) \
 		-I$(obj) -I$(srctree)/tools/testing/selftests/bpf/ \
 		-I$(LIBBPF_INCLUDE) \
 		-D__KERNEL__ -D__BPF_TRACING__ -Wno-unused-value -Wno-pointer-sign \
 		-D__TARGET_ARCH_$(SRCARCH) -Wno-compare-distinct-pointer-types \
 		-Wno-gnu-variable-sized-type-not-at-end \
 		-Wno-address-of-packed-member -Wno-tautological-compare \
 		-Wno-unknown-warning-option $(CLANG_ARCH_ARGS) \
 		-fno-asynchronous-unwind-tables -fcf-protection \
 		-I$(srctree)/samples/bpf/ -include asm_goto_workaround.h \
 		-O2 -emit-llvm -Xclang -disable-llvm-passes -c $< -o - | \
 		$(OPT) -O2 -mtriple=bpf-pc-linux | $(LLVM_DIS) | \
 		$(LLC) -march=bpf $(LLC_FLAGS) -filetype=obj -o $@
 ifeq ($(DWARF2BTF),y)
 	$(BTF_PAHOLE) -J $@
 endif
	# SPDX-License-Identifier: GPL-2.0

	BPF_SAMPLES_PATH ?= $(abspath $(src))
	TOOLS_PATH := $(BPF_SAMPLES_PATH)/../../tools

	pound := \#

	# List of programs to build
	tprogs-y := test_lru_dist
	tprogs-y += sock_example
	tprogs-y += fds_example
	tprogs-y += sockex1
	tprogs-y += sockex2
	tprogs-y += sockex3
	tprogs-y += tracex1
	tprogs-y += tracex2
	tprogs-y += tracex3
	tprogs-y += tracex4
	tprogs-y += tracex5
	tprogs-y += tracex6
	tprogs-y += tracex7
	tprogs-y += test_probe_write_user
	tprogs-y += trace_output
	tprogs-y += lathist
	tprogs-y += offwaketime
	tprogs-y += spintest
	tprogs-y += map_perf_test
	tprogs-y += test_overhead
	tprogs-y += test_cgrp2_array_pin
	tprogs-y += test_cgrp2_attach
	tprogs-y += test_cgrp2_sock
	tprogs-y += test_cgrp2_sock2
	tprogs-y += xdp_router_ipv4
	tprogs-y += test_current_task_under_cgroup
	tprogs-y += trace_event
	tprogs-y += sampleip
	tprogs-y += tc_l2_redirect
	tprogs-y += lwt_len_hist
	tprogs-y += xdp_tx_iptunnel
	tprogs-y += test_map_in_map
	tprogs-y += per_socket_stats_example
	tprogs-y += syscall_tp
	tprogs-y += cpustat
	tprogs-y += xdp_adjust_tail
	tprogs-y += xdp_fwd
	tprogs-y += task_fd_query
	tprogs-y += ibumad
	tprogs-y += hbm

	# Libbpf dependencies
	LIBBPF_SRC = $(TOOLS_PATH)/lib/bpf
	LIBBPF_OUTPUT = $(abspath $(BPF_SAMPLES_PATH))/libbpf
	LIBBPF_DESTDIR = $(LIBBPF_OUTPUT)
	LIBBPF_INCLUDE = $(LIBBPF_DESTDIR)/include
	LIBBPF = $(LIBBPF_OUTPUT)/libbpf.a

	CGROUP_HELPERS := ../../tools/testing/selftests/bpf/cgroup_helpers.o
	TRACE_HELPERS := ../../tools/testing/selftests/bpf/trace_helpers.o
	XDP_SAMPLE := xdp_sample_user.o

	fds_example-objs := fds_example.o
	sockex1-objs := sockex1_user.o
	sockex2-objs := sockex2_user.o
	sockex3-objs := sockex3_user.o
	tracex1-objs := tracex1_user.o $(TRACE_HELPERS)
	tracex2-objs := tracex2_user.o
	tracex3-objs := tracex3_user.o
	tracex4-objs := tracex4_user.o
	tracex5-objs := tracex5_user.o $(TRACE_HELPERS)
	tracex6-objs := tracex6_user.o
	tracex7-objs := tracex7_user.o
	test_probe_write_user-objs := test_probe_write_user_user.o
	trace_output-objs := trace_output_user.o
	lathist-objs := lathist_user.o
	offwaketime-objs := offwaketime_user.o $(TRACE_HELPERS)
	spintest-objs := spintest_user.o $(TRACE_HELPERS)
	map_perf_test-objs := map_perf_test_user.o
	test_overhead-objs := test_overhead_user.o
	test_cgrp2_array_pin-objs := test_cgrp2_array_pin.o
	test_cgrp2_attach-objs := test_cgrp2_attach.o
	test_cgrp2_sock-objs := test_cgrp2_sock.o
	test_cgrp2_sock2-objs := test_cgrp2_sock2.o
	test_current_task_under_cgroup-objs := $(CGROUP_HELPERS) \
	test_current_task_under_cgroup_user.o
	trace_event-objs := trace_event_user.o $(TRACE_HELPERS)
	sampleip-objs := sampleip_user.o $(TRACE_HELPERS)
	tc_l2_redirect-objs := tc_l2_redirect_user.o
	lwt_len_hist-objs := lwt_len_hist_user.o
	xdp_tx_iptunnel-objs := xdp_tx_iptunnel_user.o
	test_map_in_map-objs := test_map_in_map_user.o
	per_socket_stats_example-objs := cookie_uid_helper_example.o
	syscall_tp-objs := syscall_tp_user.o
	cpustat-objs := cpustat_user.o
	xdp_adjust_tail-objs := xdp_adjust_tail_user.o
	xdp_fwd-objs := xdp_fwd_user.o
	task_fd_query-objs := task_fd_query_user.o $(TRACE_HELPERS)
	ibumad-objs := ibumad_user.o
	hbm-objs := hbm.o $(CGROUP_HELPERS)

	xdp_router_ipv4-objs := xdp_router_ipv4_user.o $(XDP_SAMPLE)

	# Tell kbuild to always build the programs
	always-y := $(tprogs-y)
	always-y += sockex1_kern.o
	always-y += sockex2_kern.o
	always-y += sockex3_kern.o
	always-y += tracex1.bpf.o
	always-y += tracex2.bpf.o
	always-y += tracex3.bpf.o
	always-y += tracex4.bpf.o
	always-y += tracex5.bpf.o
	always-y += tracex6.bpf.o
	always-y += tracex7.bpf.o
	always-y += sock_flags.bpf.o
	always-y += test_probe_write_user.bpf.o
	always-y += trace_output.bpf.o
	always-y += tcbpf1_kern.o
	always-y += tc_l2_redirect_kern.o
	always-y += lathist_kern.o
	always-y += offwaketime.bpf.o
	always-y += spintest.bpf.o
	always-y += map_perf_test.bpf.o
	always-y += test_overhead_tp.bpf.o
	always-y += test_overhead_raw_tp.bpf.o
	always-y += test_overhead_kprobe.bpf.o
	always-y += parse_varlen.o parse_simple.o parse_ldabs.o
	always-y += test_cgrp2_tc.bpf.o
	always-y += test_current_task_under_cgroup.bpf.o
	always-y += trace_event_kern.o
	always-y += sampleip_kern.o
	always-y += lwt_len_hist.bpf.o
	always-y += xdp_tx_iptunnel_kern.o
	always-y += test_map_in_map.bpf.o
	always-y += tcp_synrto_kern.o
	always-y += tcp_rwnd_kern.o
	always-y += tcp_bufs_kern.o
	always-y += tcp_cong_kern.o
	always-y += tcp_iw_kern.o
	always-y += tcp_clamp_kern.o
	always-y += tcp_basertt_kern.o
	always-y += tcp_tos_reflect_kern.o
	always-y += tcp_dumpstats_kern.o
	always-y += xdp2skb_meta_kern.o
	always-y += syscall_tp_kern.o
	always-y += cpustat_kern.o
	always-y += xdp_adjust_tail_kern.o
	always-y += xdp_fwd_kern.o
	always-y += task_fd_query_kern.o
	always-y += ibumad_kern.o
	always-y += hbm_out_kern.o
	always-y += hbm_edt_kern.o

	TPROGS_CFLAGS = $(TPROGS_USER_CFLAGS)
	TPROGS_LDFLAGS = $(TPROGS_USER_LDFLAGS)

	ifeq ($(ARCH), arm)
	# Strip all except -D__LINUX_ARM_ARCH__ option needed to handle linux
	# headers when arm instruction set identification is requested.
	ARM_ARCH_SELECTOR := $(filter -D__LINUX_ARM_ARCH__%, $(KBUILD_CFLAGS))
	BPF_EXTRA_CFLAGS := $(ARM_ARCH_SELECTOR)
	TPROGS_CFLAGS += $(ARM_ARCH_SELECTOR)
	endif

	ifeq ($(ARCH), mips)
	TPROGS_CFLAGS += -D__SANE_USERSPACE_TYPES__
	ifdef CONFIG_MACH_LOONGSON64
	BPF_EXTRA_CFLAGS += -I$(srctree)/arch/mips/include/asm/mach-loongson64
	BPF_EXTRA_CFLAGS += -I$(srctree)/arch/mips/include/asm/mach-generic
	endif
	endif

	TPROGS_CFLAGS += -Wall -O2
	TPROGS_CFLAGS += -Wmissing-prototypes
	TPROGS_CFLAGS += -Wstrict-prototypes
	TPROGS_CFLAGS += $(call try-run,\
	printf "int main() { return 0; }" \|\
	$(CC) -Werror -fsanitize=bounds -x c - -o "$$TMP",-fsanitize=bounds,)

	TPROGS_CFLAGS += -I$(objtree)/usr/include
	TPROGS_CFLAGS += -I$(srctree)/tools/testing/selftests/bpf/
	TPROGS_CFLAGS += -I$(LIBBPF_INCLUDE)
	TPROGS_CFLAGS += -I$(srctree)/tools/include
	TPROGS_CFLAGS += -I$(srctree)/tools/perf
	TPROGS_CFLAGS += -I$(srctree)/tools/lib
	TPROGS_CFLAGS += -DHAVE_ATTR_TEST=0

	ifdef SYSROOT
	TPROGS_CFLAGS += --sysroot=$(SYSROOT)
	TPROGS_LDFLAGS := -L$(SYSROOT)/usr/lib
	endif

	TPROGS_LDLIBS += $(LIBBPF) -lelf -lz
	TPROGLDLIBS_xdp_router_ipv4 += -lm -pthread
	TPROGLDLIBS_tracex4 += -lrt
	TPROGLDLIBS_trace_output += -lrt
	TPROGLDLIBS_map_perf_test += -lrt
	TPROGLDLIBS_test_overhead += -lrt

	# Allows pointing LLC/CLANG to a LLVM backend with bpf support, redefine on cmdline:
	# make M=samples/bpf LLC=~/git/llvm-project/llvm/build/bin/llc CLANG=~/git/llvm-project/llvm/build/bin/clang
	LLC ?= llc
	CLANG ?= clang
	OPT ?= opt
	LLVM_DIS ?= llvm-dis
	LLVM_OBJCOPY ?= llvm-objcopy
	LLVM_READELF ?= llvm-readelf
	BTF_PAHOLE ?= pahole

	# Detect that we're cross compiling and use the cross compiler
	ifdef CROSS_COMPILE
	CLANG_ARCH_ARGS = --target=$(notdir $(CROSS_COMPILE:%-=%))
	endif

	# Don't evaluate probes and warnings if we need to run make recursively
	ifneq ($(src),)
	HDR_PROBE := $(shell printf "$(pound)include <linux/types.h>\n struct list_head { int a; }; int main() { return 0; }" \| \
	$(CC) $(TPROGS_CFLAGS) $(TPROGS_LDFLAGS) -x c - \
	-o /dev/null 2>/dev/null && echo okay)

	ifeq ($(HDR_PROBE),)
	$(warning WARNING: Detected possible issues with include path.)
	$(warning WARNING: Please install kernel headers locally (make headers_install).)
	endif

	BTF_LLC_PROBE := $(shell $(LLC) -march=bpf -mattr=help 2>&1 \| grep dwarfris)
	BTF_PAHOLE_PROBE := $(shell $(BTF_PAHOLE) --help 2>&1 \| grep BTF)
	BTF_OBJCOPY_PROBE := $(shell $(LLVM_OBJCOPY) --help 2>&1 \| grep -i 'usage.*llvm')
	BTF_LLVM_PROBE := $(shell echo "int main() { return 0; }" \| \
	$(CLANG) --target=bpf -O2 -g -c -x c - -o ./llvm_btf_verify.o; \
	$(LLVM_READELF) -S ./llvm_btf_verify.o \| grep BTF; \
	/bin/rm -f ./llvm_btf_verify.o)

	BPF_EXTRA_CFLAGS += -fno-stack-protector
	ifneq ($(BTF_LLVM_PROBE),)
	BPF_EXTRA_CFLAGS += -g
	else
	ifneq ($(and $(BTF_LLC_PROBE),$(BTF_PAHOLE_PROBE),$(BTF_OBJCOPY_PROBE)),)
	BPF_EXTRA_CFLAGS += -g
	LLC_FLAGS += -mattr=dwarfris
	DWARF2BTF = y
	endif
	endif
	endif

	# Trick to allow make to be run from this directory
	all:
	$(MAKE) -C ../../ M=$(CURDIR) BPF_SAMPLES_PATH=$(CURDIR)

	clean:
	$(MAKE) -C ../../ M=$(CURDIR) clean
	@find $(CURDIR) -type f -name '*~' -delete
	@$(RM) -r $(CURDIR)/libbpf $(CURDIR)/bpftool

	$(LIBBPF): $(wildcard $(LIBBPF_SRC)/*.[ch] $(LIBBPF_SRC)/Makefile) \| $(LIBBPF_OUTPUT)
	# Fix up variables inherited from Kbuild that tools/ build system won't like
	$(MAKE) -C $(LIBBPF_SRC) RM='rm -rf' EXTRA_CFLAGS="$(TPROGS_CFLAGS)" \
	LDFLAGS="$(TPROGS_LDFLAGS)" srctree=$(BPF_SAMPLES_PATH)/../../ \
	O= OUTPUT=$(LIBBPF_OUTPUT)/ DESTDIR=$(LIBBPF_DESTDIR) prefix= \
	$@ install_headers

	BPFTOOLDIR := $(TOOLS_PATH)/bpf/bpftool
	BPFTOOL_OUTPUT := $(abspath $(BPF_SAMPLES_PATH))/bpftool
	DEFAULT_BPFTOOL := $(BPFTOOL_OUTPUT)/bootstrap/bpftool
	BPFTOOL ?= $(DEFAULT_BPFTOOL)
	$(DEFAULT_BPFTOOL): $(wildcard $(BPFTOOLDIR)/*.[ch] $(BPFTOOLDIR)/Makefile) \| $(BPFTOOL_OUTPUT)
	$(MAKE) -C $(BPFTOOLDIR) srctree=$(BPF_SAMPLES_PATH)/../../ \
	OUTPUT=$(BPFTOOL_OUTPUT)/ bootstrap

	$(LIBBPF_OUTPUT) $(BPFTOOL_OUTPUT):
	$(call msg,MKDIR,$@)
	$(Q)mkdir -p $@

	$(obj)/syscall_nrs.h: $(obj)/syscall_nrs.s FORCE
	$(call filechk,offsets,__SYSCALL_NRS_H__)

	targets += syscall_nrs.s
	clean-files += syscall_nrs.h

	FORCE:


	# Verify LLVM compiler tools are available and bpf target is supported by llc
	.PHONY: verify_cmds verify_target_bpf $(CLANG) $(LLC)

	verify_cmds: $(CLANG) $(LLC)
	@for TOOL in $^ ; do \
	if ! (which -- "$${TOOL}" > /dev/null 2>&1); then \
	echo "*** ERROR: Cannot find LLVM tool $${TOOL}" ;\
	exit 1; \
	else true; fi; \
	done

	verify_target_bpf: verify_cmds
	@if ! (${LLC} -march=bpf -mattr=help > /dev/null 2>&1); then \
	echo "*** ERROR: LLVM (${LLC}) does not support 'bpf' target" ;\
	echo " NOTICE: LLVM version >= 3.7.1 required" ;\
	exit 2; \
	else true; fi

	$(BPF_SAMPLES_PATH)/*.c: verify_target_bpf $(LIBBPF)
	$(src)/*.c: verify_target_bpf $(LIBBPF)

	libbpf_hdrs: $(LIBBPF)
	$(obj)/$(TRACE_HELPERS) $(obj)/$(CGROUP_HELPERS) $(obj)/$(XDP_SAMPLE): \| libbpf_hdrs

	.PHONY: libbpf_hdrs

	$(obj)/xdp_router_ipv4_user.o: $(obj)/xdp_router_ipv4.skel.h

	$(obj)/tracex5.bpf.o: $(obj)/syscall_nrs.h
	$(obj)/hbm_out_kern.o: $(src)/hbm.h $(src)/hbm_kern.h
	$(obj)/hbm.o: $(src)/hbm.h
	$(obj)/hbm_edt_kern.o: $(src)/hbm.h $(src)/hbm_kern.h

	# Override includes for xdp_sample_user.o because $(srctree)/usr/include in
	# TPROGS_CFLAGS causes conflicts
	XDP_SAMPLE_CFLAGS += -Wall -O2 \
	-I$(src)/../../tools/include \
	-I$(src)/../../tools/include/uapi \
	-I$(LIBBPF_INCLUDE) \
	-I$(src)/../../tools/testing/selftests/bpf

	$(obj)/$(XDP_SAMPLE): TPROGS_CFLAGS = $(XDP_SAMPLE_CFLAGS) $(TPROGS_USER_CFLAGS)
	$(obj)/$(XDP_SAMPLE): $(src)/xdp_sample_user.h $(src)/xdp_sample_shared.h
	# Override includes for trace_helpers.o because __must_check won't be defined
	# in our include path.
	$(obj)/$(TRACE_HELPERS): TPROGS_CFLAGS := $(TPROGS_CFLAGS) -D__must_check=

	-include $(BPF_SAMPLES_PATH)/Makefile.target

	VMLINUX_BTF_PATHS ?= $(abspath $(if $(O),$(O)/vmlinux)) \
	$(abspath $(if $(KBUILD_OUTPUT),$(KBUILD_OUTPUT)/vmlinux)) \
	$(abspath ./vmlinux)
	VMLINUX_BTF ?= $(abspath $(firstword $(wildcard $(VMLINUX_BTF_PATHS))))

	$(obj)/vmlinux.h: $(VMLINUX_BTF) $(BPFTOOL)
	ifeq ($(VMLINUX_H),)
	ifeq ($(VMLINUX_BTF),)
	$(error Cannot find a vmlinux for VMLINUX_BTF at any of "$(VMLINUX_BTF_PATHS)",\
	build the kernel or set VMLINUX_BTF like "VMLINUX_BTF=/sys/kernel/btf/vmlinux" or VMLINUX_H variable)
	endif
	$(Q)$(BPFTOOL) btf dump file $(VMLINUX_BTF) format c > $@
	else
	$(Q)cp "$(VMLINUX_H)" $@
	endif

	clean-files += vmlinux.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.
	#
	# Use '-idirafter': Don't interfere with include mechanics except where the
	# build would have failed anyways.
	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 }') \
	$(shell $(1) -dM -E - </dev/null \| grep '#define __riscv_xlen ' \| sed 's/#define /-D/' \| sed 's/ /=/')
	endef

	CLANG_SYS_INCLUDES = $(call get_sys_includes,$(CLANG))

	$(obj)/xdp_router_ipv4.bpf.o: $(obj)/xdp_sample.bpf.o

	$(obj)/%.bpf.o: $(src)/%.bpf.c $(obj)/vmlinux.h $(src)/xdp_sample.bpf.h $(src)/xdp_sample_shared.h
	@echo " CLANG-BPF " $@
	$(Q)$(CLANG) -g -O2 --target=bpf -D__TARGET_ARCH_$(SRCARCH) \
	-Wno-compare-distinct-pointer-types -I$(srctree)/include \
	-I$(srctree)/samples/bpf -I$(srctree)/tools/include \
	-I$(LIBBPF_INCLUDE) $(CLANG_SYS_INCLUDES) \
	-c $(filter %.bpf.c,$^) -o $@

	LINKED_SKELS := xdp_router_ipv4.skel.h
	clean-files += $(LINKED_SKELS)

	xdp_router_ipv4.skel.h-deps := xdp_router_ipv4.bpf.o xdp_sample.bpf.o

	LINKED_BPF_SRCS := $(patsubst %.bpf.o,%.bpf.c,$(foreach skel,$(LINKED_SKELS),$($(skel)-deps)))

	BPF_SRCS_LINKED := $(notdir $(wildcard $(src)/*.bpf.c))
	BPF_OBJS_LINKED := $(patsubst %.bpf.c,$(obj)/%.bpf.o, $(BPF_SRCS_LINKED))
	BPF_SKELS_LINKED := $(addprefix $(obj)/,$(LINKED_SKELS))

	$(BPF_SKELS_LINKED): $(BPF_OBJS_LINKED) $(BPFTOOL)
	@echo " BPF GEN-OBJ " $(@:.skel.h=)
	$(Q)$(BPFTOOL) gen object $(@:.skel.h=.lbpf.o) $(addprefix $(obj)/,$($(@F)-deps))
	@echo " BPF GEN-SKEL" $(@:.skel.h=)
	$(Q)$(BPFTOOL) gen skeleton $(@:.skel.h=.lbpf.o) name $(notdir $(@:.skel.h=)) > $@

	# asm/sysreg.h - inline assembly used by it is incompatible with llvm.
	# But, there is no easy way to fix it, so just exclude it since it is
	# useless for BPF samples.
	# below we use long chain of commands, clang \| opt \| llvm-dis \| llc,
	# to generate final object file. 'clang' compiles the source into IR
	# with native target, e.g., x64, arm64, etc. 'opt' does bpf CORE IR builtin
	# processing (llvm12) and IR optimizations. 'llvm-dis' converts
	# 'opt' output to IR, and finally 'llc' generates bpf byte code.
	$(obj)/%.o: $(src)/%.c
	@echo " CLANG-bpf " $@
	$(Q)$(CLANG) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(BPF_EXTRA_CFLAGS) \
	-I$(obj) -I$(srctree)/tools/testing/selftests/bpf/ \
	-I$(LIBBPF_INCLUDE) \
	-D__KERNEL__ -D__BPF_TRACING__ -Wno-unused-value -Wno-pointer-sign \
	-D__TARGET_ARCH_$(SRCARCH) -Wno-compare-distinct-pointer-types \
	-Wno-gnu-variable-sized-type-not-at-end \
	-Wno-address-of-packed-member -Wno-tautological-compare \
	-Wno-unknown-warning-option $(CLANG_ARCH_ARGS) \
	-fno-asynchronous-unwind-tables -fcf-protection \
	-I$(srctree)/samples/bpf/ -include asm_goto_workaround.h \
	-O2 -emit-llvm -Xclang -disable-llvm-passes -c $< -o - \| \
	$(OPT) -O2 -mtriple=bpf-pc-linux \| $(LLVM_DIS) \| \
	$(LLC) -march=bpf $(LLC_FLAGS) -filetype=obj -o $@
	ifeq ($(DWARF2BTF),y)
	$(BTF_PAHOLE) -J $@
	endif