linux/samples/bpf/Makefile
Quentin Monnet a60d24e740 samples/bpf: Do not FORCE-recompile libbpf
In samples/bpf/Makefile, libbpf has a FORCE dependency that force it to
be rebuilt. I read this as a way to keep the library up-to-date, given
that we do not have, in samples/bpf, a list of the source files for
libbpf itself. However, a better approach would be to use the
"$(wildcard ...)" function from make, and to have libbpf depend on all
the .c and .h files in its directory. This is what samples/bpf/Makefile
does for bpftool, and also what the BPF selftests' Makefile does for
libbpf.

Let's update the Makefile to avoid rebuilding libbpf all the time (and
bpftool on top of it).

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211007194438.34443-11-quentin@isovalent.com
2021-10-08 12:02:36 -07:00

443 lines
15 KiB
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 += xdp1
tprogs-y += xdp2
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 += xdp_rxq_info
tprogs-y += syscall_tp
tprogs-y += cpustat
tprogs-y += xdp_adjust_tail
tprogs-y += xdpsock
tprogs-y += xdpsock_ctrl_proc
tprogs-y += xsk_fwd
tprogs-y += xdp_fwd
tprogs-y += task_fd_query
tprogs-y += xdp_sample_pkts
tprogs-y += ibumad
tprogs-y += hbm
tprogs-y += xdp_redirect_cpu
tprogs-y += xdp_redirect_map_multi
tprogs-y += xdp_redirect_map
tprogs-y += xdp_redirect
tprogs-y += xdp_monitor
# 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
xdp1-objs := xdp1_user.o
# reuse xdp1 source intentionally
xdp2-objs := xdp1_user.o
xdp_router_ipv4-objs := xdp_router_ipv4_user.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
xdp_rxq_info-objs := xdp_rxq_info_user.o
syscall_tp-objs := syscall_tp_user.o
cpustat-objs := cpustat_user.o
xdp_adjust_tail-objs := xdp_adjust_tail_user.o
xdpsock-objs := xdpsock_user.o
xdpsock_ctrl_proc-objs := xdpsock_ctrl_proc.o
xsk_fwd-objs := xsk_fwd.o
xdp_fwd-objs := xdp_fwd_user.o
task_fd_query-objs := task_fd_query_user.o $(TRACE_HELPERS)
xdp_sample_pkts-objs := xdp_sample_pkts_user.o
ibumad-objs := ibumad_user.o
hbm-objs := hbm.o $(CGROUP_HELPERS)
xdp_redirect_map_multi-objs := xdp_redirect_map_multi_user.o $(XDP_SAMPLE)
xdp_redirect_cpu-objs := xdp_redirect_cpu_user.o $(XDP_SAMPLE)
xdp_redirect_map-objs := xdp_redirect_map_user.o $(XDP_SAMPLE)
xdp_redirect-objs := xdp_redirect_user.o $(XDP_SAMPLE)
xdp_monitor-objs := xdp_monitor_user.o $(XDP_SAMPLE)
# Tell kbuild to always build the programs
always-y := $(tprogs-y)
always-y += sockex1_kern.o
always-y += sockex2_kern.o
always-y += sockex3_kern.o
always-y += tracex1_kern.o
always-y += tracex2_kern.o
always-y += tracex3_kern.o
always-y += tracex4_kern.o
always-y += tracex5_kern.o
always-y += tracex6_kern.o
always-y += tracex7_kern.o
always-y += sock_flags_kern.o
always-y += test_probe_write_user_kern.o
always-y += trace_output_kern.o
always-y += tcbpf1_kern.o
always-y += tc_l2_redirect_kern.o
always-y += lathist_kern.o
always-y += offwaketime_kern.o
always-y += spintest_kern.o
always-y += map_perf_test_kern.o
always-y += test_overhead_tp_kern.o
always-y += test_overhead_raw_tp_kern.o
always-y += test_overhead_kprobe_kern.o
always-y += parse_varlen.o parse_simple.o parse_ldabs.o
always-y += test_cgrp2_tc_kern.o
always-y += xdp1_kern.o
always-y += xdp2_kern.o
always-y += xdp_router_ipv4_kern.o
always-y += test_current_task_under_cgroup_kern.o
always-y += trace_event_kern.o
always-y += sampleip_kern.o
always-y += lwt_len_hist_kern.o
always-y += xdp_tx_iptunnel_kern.o
always-y += test_map_in_map_kern.o
always-y += tcp_synrto_kern.o
always-y += tcp_rwnd_kern.o
always-y += tcp_bufs_kern.o
always-y += tcp_cong_kern.o
always-y += tcp_iw_kern.o
always-y += tcp_clamp_kern.o
always-y += tcp_basertt_kern.o
always-y += tcp_tos_reflect_kern.o
always-y += tcp_dumpstats_kern.o
always-y += xdp_rxq_info_kern.o
always-y += xdp2skb_meta_kern.o
always-y += syscall_tp_kern.o
always-y += cpustat_kern.o
always-y += xdp_adjust_tail_kern.o
always-y += xdp_fwd_kern.o
always-y += task_fd_query_kern.o
always-y += xdp_sample_pkts_kern.o
always-y += ibumad_kern.o
always-y += hbm_out_kern.o
always-y += hbm_edt_kern.o
always-y += xdpsock_kern.o
ifeq ($(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
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 += $(LIBBPF) -lelf -lz
TPROGLDLIBS_tracex4 += -lrt
TPROGLDLIBS_trace_output += -lrt
TPROGLDLIBS_map_perf_test += -lrt
TPROGLDLIBS_test_overhead += -lrt
TPROGLDLIBS_xdpsock += -pthread -lcap
TPROGLDLIBS_xsk_fwd += -pthread
# Allows pointing LLC/CLANG to a LLVM backend with bpf support, redefine on cmdline:
# make M=samples/bpf LLC=~/git/llvm-project/llvm/build/bin/llc CLANG=~/git/llvm-project/llvm/build/bin/clang
LLC ?= llc
CLANG ?= clang
OPT ?= opt
LLVM_DIS ?= llvm-dis
LLVM_OBJCOPY ?= llvm-objcopy
BTF_PAHOLE ?= pahole
# Detect that we're cross compiling and use the cross compiler
ifdef CROSS_COMPILE
CLANG_ARCH_ARGS = --target=$(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; }" | \
$(CLANG) -target bpf -O2 -g -c -x c - -o ./llvm_btf_verify.o; \
readelf -S ./llvm_btf_verify.o | grep BTF; \
/bin/rm -f ./llvm_btf_verify.o)
BPF_EXTRA_CFLAGS += -fno-stack-protector
ifneq ($(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)/bpftool
$(BPFTOOL): $(LIBBPF) $(wildcard $(BPFTOOLDIR)/*.[ch] $(BPFTOOLDIR)/Makefile) | $(BPFTOOL_OUTPUT)
$(MAKE) -C $(BPFTOOLDIR) srctree=$(BPF_SAMPLES_PATH)/../../ \
OUTPUT=$(BPFTOOL_OUTPUT)/ \
LIBBPF_OUTPUT=$(LIBBPF_OUTPUT)/ \
LIBBPF_DESTDIR=$(LIBBPF_DESTDIR)/
$(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): | libbpf_hdrs
.PHONY: libbpf_hdrs
$(obj)/xdp_redirect_cpu_user.o: $(obj)/xdp_redirect_cpu.skel.h
$(obj)/xdp_redirect_map_multi_user.o: $(obj)/xdp_redirect_map_multi.skel.h
$(obj)/xdp_redirect_map_user.o: $(obj)/xdp_redirect_map.skel.h
$(obj)/xdp_redirect_user.o: $(obj)/xdp_redirect.skel.h
$(obj)/xdp_monitor_user.o: $(obj)/xdp_monitor.skel.h
$(obj)/tracex5_kern.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
-include $(BPF_SAMPLES_PATH)/Makefile.target
VMLINUX_BTF_PATHS ?= $(if $(O),$(O)/vmlinux) \
$(if $(KBUILD_OUTPUT),$(KBUILD_OUTPUT)/vmlinux) \
../../../../vmlinux \
/sys/kernel/btf/vmlinux \
/boot/vmlinux-$(shell uname -r)
VMLINUX_BTF ?= $(abspath $(firstword $(wildcard $(VMLINUX_BTF_PATHS))))
ifeq ($(VMLINUX_BTF),)
$(error Cannot find a vmlinux for VMLINUX_BTF at any of "$(VMLINUX_BTF_PATHS)")
endif
$(obj)/vmlinux.h: $(VMLINUX_BTF) $(BPFTOOL)
ifeq ($(VMLINUX_H),)
$(Q)$(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_redirect_cpu.bpf.o: $(obj)/xdp_sample.bpf.o
$(obj)/xdp_redirect_map_multi.bpf.o: $(obj)/xdp_sample.bpf.o
$(obj)/xdp_redirect_map.bpf.o: $(obj)/xdp_sample.bpf.o
$(obj)/xdp_redirect.bpf.o: $(obj)/xdp_sample.bpf.o
$(obj)/xdp_monitor.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_redirect_cpu.skel.h xdp_redirect_map_multi.skel.h \
xdp_redirect_map.skel.h xdp_redirect.skel.h xdp_monitor.skel.h
clean-files += $(LINKED_SKELS)
xdp_redirect_cpu.skel.h-deps := xdp_redirect_cpu.bpf.o xdp_sample.bpf.o
xdp_redirect_map_multi.skel.h-deps := xdp_redirect_map_multi.bpf.o xdp_sample.bpf.o
xdp_redirect_map.skel.h-deps := xdp_redirect_map.bpf.o xdp_sample.bpf.o
xdp_redirect.skel.h-deps := xdp_redirect.bpf.o xdp_sample.bpf.o
xdp_monitor.skel.h-deps := xdp_monitor.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 $(CLANG_ARCH_ARGS) \
-fno-asynchronous-unwind-tables \
-I$(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