linux-yocto/samples/bpf/Makefile

SPDX-License-Identifier: GPL-2.0

BPF_SAMPLES_PATH ?= $(abspath $(srctree)/$(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

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

ifeq ($(ARCH), x86) BPF_EXTRA_CFLAGS += -fcf-protection endif

TPROGS_CFLAGS += -Wall -O2 TPROGS_CFLAGS += -Wmissing-prototypes TPROGS_CFLAGS += -Wstrict-prototypes

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 += -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 BPFTOOL := $(BPFTOOL_OUTPUT)/bootstrap/bpftool $(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) $(obj)/$(XDP_SAMPLE): $(src)/xdp_sample_user.h $(src)/xdp_sample_shared.h

-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 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) $(CLANG_SYS_INCLUDES)
-D__KERNEL__ -D__BPF_TRACING__ -Wno-unused-value -Wno-pointer-sign
-D__TARGET_ARCH_$(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 $(CLANG_ARCH_ARGS)
-fno-asynchronous-unwind-tables
-I$(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