xref: /openbmc/linux/samples/bpf/Makefile (revision fc843ccd)
1# SPDX-License-Identifier: GPL-2.0
2
3BPF_SAMPLES_PATH ?= $(abspath $(srctree)/$(src))
4TOOLS_PATH := $(BPF_SAMPLES_PATH)/../../tools
5
6pound := \#
7
8# List of programs to build
9tprogs-y := test_lru_dist
10tprogs-y += sock_example
11tprogs-y += fds_example
12tprogs-y += sockex1
13tprogs-y += sockex2
14tprogs-y += sockex3
15tprogs-y += tracex1
16tprogs-y += tracex2
17tprogs-y += tracex3
18tprogs-y += tracex4
19tprogs-y += tracex5
20tprogs-y += tracex6
21tprogs-y += tracex7
22tprogs-y += test_probe_write_user
23tprogs-y += trace_output
24tprogs-y += lathist
25tprogs-y += offwaketime
26tprogs-y += spintest
27tprogs-y += map_perf_test
28tprogs-y += test_overhead
29tprogs-y += test_cgrp2_array_pin
30tprogs-y += test_cgrp2_attach
31tprogs-y += test_cgrp2_sock
32tprogs-y += test_cgrp2_sock2
33tprogs-y += xdp1
34tprogs-y += xdp2
35tprogs-y += xdp_router_ipv4
36tprogs-y += test_current_task_under_cgroup
37tprogs-y += trace_event
38tprogs-y += sampleip
39tprogs-y += tc_l2_redirect
40tprogs-y += lwt_len_hist
41tprogs-y += xdp_tx_iptunnel
42tprogs-y += test_map_in_map
43tprogs-y += per_socket_stats_example
44tprogs-y += xdp_rxq_info
45tprogs-y += syscall_tp
46tprogs-y += cpustat
47tprogs-y += xdp_adjust_tail
48tprogs-y += xdpsock
49tprogs-y += xdpsock_ctrl_proc
50tprogs-y += xsk_fwd
51tprogs-y += xdp_fwd
52tprogs-y += task_fd_query
53tprogs-y += xdp_sample_pkts
54tprogs-y += ibumad
55tprogs-y += hbm
56
57tprogs-y += xdp_redirect_cpu
58tprogs-y += xdp_redirect_map_multi
59tprogs-y += xdp_redirect_map
60tprogs-y += xdp_redirect
61tprogs-y += xdp_monitor
62
63# Libbpf dependencies
64LIBBPF_SRC = $(TOOLS_PATH)/lib/bpf
65LIBBPF_OUTPUT = $(abspath $(BPF_SAMPLES_PATH))/libbpf
66LIBBPF_DESTDIR = $(LIBBPF_OUTPUT)
67LIBBPF_INCLUDE = $(LIBBPF_DESTDIR)/include
68LIBBPF = $(LIBBPF_OUTPUT)/libbpf.a
69
70CGROUP_HELPERS := ../../tools/testing/selftests/bpf/cgroup_helpers.o
71TRACE_HELPERS := ../../tools/testing/selftests/bpf/trace_helpers.o
72XDP_SAMPLE := xdp_sample_user.o
73
74fds_example-objs := fds_example.o
75sockex1-objs := sockex1_user.o
76sockex2-objs := sockex2_user.o
77sockex3-objs := sockex3_user.o
78tracex1-objs := tracex1_user.o $(TRACE_HELPERS)
79tracex2-objs := tracex2_user.o
80tracex3-objs := tracex3_user.o
81tracex4-objs := tracex4_user.o
82tracex5-objs := tracex5_user.o $(TRACE_HELPERS)
83tracex6-objs := tracex6_user.o
84tracex7-objs := tracex7_user.o
85test_probe_write_user-objs := test_probe_write_user_user.o
86trace_output-objs := trace_output_user.o
87lathist-objs := lathist_user.o
88offwaketime-objs := offwaketime_user.o $(TRACE_HELPERS)
89spintest-objs := spintest_user.o $(TRACE_HELPERS)
90map_perf_test-objs := map_perf_test_user.o
91test_overhead-objs := test_overhead_user.o
92test_cgrp2_array_pin-objs := test_cgrp2_array_pin.o
93test_cgrp2_attach-objs := test_cgrp2_attach.o
94test_cgrp2_sock-objs := test_cgrp2_sock.o
95test_cgrp2_sock2-objs := test_cgrp2_sock2.o
96xdp1-objs := xdp1_user.o
97# reuse xdp1 source intentionally
98xdp2-objs := xdp1_user.o
99test_current_task_under_cgroup-objs := $(CGROUP_HELPERS) \
100				       test_current_task_under_cgroup_user.o
101trace_event-objs := trace_event_user.o $(TRACE_HELPERS)
102sampleip-objs := sampleip_user.o $(TRACE_HELPERS)
103tc_l2_redirect-objs := tc_l2_redirect_user.o
104lwt_len_hist-objs := lwt_len_hist_user.o
105xdp_tx_iptunnel-objs := xdp_tx_iptunnel_user.o
106test_map_in_map-objs := test_map_in_map_user.o
107per_socket_stats_example-objs := cookie_uid_helper_example.o
108xdp_rxq_info-objs := xdp_rxq_info_user.o
109syscall_tp-objs := syscall_tp_user.o
110cpustat-objs := cpustat_user.o
111xdp_adjust_tail-objs := xdp_adjust_tail_user.o
112xdpsock-objs := xdpsock_user.o
113xdpsock_ctrl_proc-objs := xdpsock_ctrl_proc.o
114xsk_fwd-objs := xsk_fwd.o
115xdp_fwd-objs := xdp_fwd_user.o
116task_fd_query-objs := task_fd_query_user.o $(TRACE_HELPERS)
117xdp_sample_pkts-objs := xdp_sample_pkts_user.o
118ibumad-objs := ibumad_user.o
119hbm-objs := hbm.o $(CGROUP_HELPERS)
120
121xdp_redirect_map_multi-objs := xdp_redirect_map_multi_user.o $(XDP_SAMPLE)
122xdp_redirect_cpu-objs := xdp_redirect_cpu_user.o $(XDP_SAMPLE)
123xdp_redirect_map-objs := xdp_redirect_map_user.o $(XDP_SAMPLE)
124xdp_redirect-objs := xdp_redirect_user.o $(XDP_SAMPLE)
125xdp_monitor-objs := xdp_monitor_user.o $(XDP_SAMPLE)
126xdp_router_ipv4-objs := xdp_router_ipv4_user.o $(XDP_SAMPLE)
127
128# Tell kbuild to always build the programs
129always-y := $(tprogs-y)
130always-y += sockex1_kern.o
131always-y += sockex2_kern.o
132always-y += sockex3_kern.o
133always-y += tracex1_kern.o
134always-y += tracex2_kern.o
135always-y += tracex3_kern.o
136always-y += tracex4_kern.o
137always-y += tracex5_kern.o
138always-y += tracex6_kern.o
139always-y += tracex7_kern.o
140always-y += sock_flags_kern.o
141always-y += test_probe_write_user_kern.o
142always-y += trace_output_kern.o
143always-y += tcbpf1_kern.o
144always-y += tc_l2_redirect_kern.o
145always-y += lathist_kern.o
146always-y += offwaketime_kern.o
147always-y += spintest_kern.o
148always-y += map_perf_test_kern.o
149always-y += test_overhead_tp_kern.o
150always-y += test_overhead_raw_tp_kern.o
151always-y += test_overhead_kprobe_kern.o
152always-y += parse_varlen.o parse_simple.o parse_ldabs.o
153always-y += test_cgrp2_tc_kern.o
154always-y += xdp1_kern.o
155always-y += xdp2_kern.o
156always-y += test_current_task_under_cgroup_kern.o
157always-y += trace_event_kern.o
158always-y += sampleip_kern.o
159always-y += lwt_len_hist_kern.o
160always-y += xdp_tx_iptunnel_kern.o
161always-y += test_map_in_map_kern.o
162always-y += tcp_synrto_kern.o
163always-y += tcp_rwnd_kern.o
164always-y += tcp_bufs_kern.o
165always-y += tcp_cong_kern.o
166always-y += tcp_iw_kern.o
167always-y += tcp_clamp_kern.o
168always-y += tcp_basertt_kern.o
169always-y += tcp_tos_reflect_kern.o
170always-y += tcp_dumpstats_kern.o
171always-y += xdp_rxq_info_kern.o
172always-y += xdp2skb_meta_kern.o
173always-y += syscall_tp_kern.o
174always-y += cpustat_kern.o
175always-y += xdp_adjust_tail_kern.o
176always-y += xdp_fwd_kern.o
177always-y += task_fd_query_kern.o
178always-y += xdp_sample_pkts_kern.o
179always-y += ibumad_kern.o
180always-y += hbm_out_kern.o
181always-y += hbm_edt_kern.o
182always-y += xdpsock_kern.o
183
184ifeq ($(ARCH), arm)
185# Strip all except -D__LINUX_ARM_ARCH__ option needed to handle linux
186# headers when arm instruction set identification is requested.
187ARM_ARCH_SELECTOR := $(filter -D__LINUX_ARM_ARCH__%, $(KBUILD_CFLAGS))
188BPF_EXTRA_CFLAGS := $(ARM_ARCH_SELECTOR)
189TPROGS_CFLAGS += $(ARM_ARCH_SELECTOR)
190endif
191
192ifeq ($(ARCH), mips)
193TPROGS_CFLAGS += -D__SANE_USERSPACE_TYPES__
194ifdef CONFIG_MACH_LOONGSON64
195BPF_EXTRA_CFLAGS += -I$(srctree)/arch/mips/include/asm/mach-loongson64
196BPF_EXTRA_CFLAGS += -I$(srctree)/arch/mips/include/asm/mach-generic
197endif
198endif
199
200TPROGS_CFLAGS += -Wall -O2
201TPROGS_CFLAGS += -Wmissing-prototypes
202TPROGS_CFLAGS += -Wstrict-prototypes
203
204TPROGS_CFLAGS += -I$(objtree)/usr/include
205TPROGS_CFLAGS += -I$(srctree)/tools/testing/selftests/bpf/
206TPROGS_CFLAGS += -I$(LIBBPF_INCLUDE)
207TPROGS_CFLAGS += -I$(srctree)/tools/include
208TPROGS_CFLAGS += -I$(srctree)/tools/perf
209TPROGS_CFLAGS += -DHAVE_ATTR_TEST=0
210
211ifdef SYSROOT
212TPROGS_CFLAGS += --sysroot=$(SYSROOT)
213TPROGS_LDFLAGS := -L$(SYSROOT)/usr/lib
214endif
215
216TPROGS_LDLIBS			+= $(LIBBPF) -lelf -lz
217TPROGLDLIBS_xdp_monitor		+= -lm
218TPROGLDLIBS_xdp_redirect	+= -lm
219TPROGLDLIBS_xdp_redirect_cpu	+= -lm
220TPROGLDLIBS_xdp_redirect_map	+= -lm
221TPROGLDLIBS_xdp_redirect_map_multi += -lm
222TPROGLDLIBS_xdp_router_ipv4	+= -lm
223TPROGLDLIBS_tracex4		+= -lrt
224TPROGLDLIBS_trace_output	+= -lrt
225TPROGLDLIBS_map_perf_test	+= -lrt
226TPROGLDLIBS_test_overhead	+= -lrt
227TPROGLDLIBS_xdpsock		+= -pthread -lcap
228TPROGLDLIBS_xsk_fwd		+= -pthread
229
230# Allows pointing LLC/CLANG to a LLVM backend with bpf support, redefine on cmdline:
231# make M=samples/bpf LLC=~/git/llvm-project/llvm/build/bin/llc CLANG=~/git/llvm-project/llvm/build/bin/clang
232LLC ?= llc
233CLANG ?= clang
234OPT ?= opt
235LLVM_DIS ?= llvm-dis
236LLVM_OBJCOPY ?= llvm-objcopy
237LLVM_READELF ?= llvm-readelf
238BTF_PAHOLE ?= pahole
239
240# Detect that we're cross compiling and use the cross compiler
241ifdef CROSS_COMPILE
242CLANG_ARCH_ARGS = --target=$(notdir $(CROSS_COMPILE:%-=%))
243endif
244
245# Don't evaluate probes and warnings if we need to run make recursively
246ifneq ($(src),)
247HDR_PROBE := $(shell printf "$(pound)include <linux/types.h>\n struct list_head { int a; }; int main() { return 0; }" | \
248	$(CC) $(TPROGS_CFLAGS) $(TPROGS_LDFLAGS) -x c - \
249	-o /dev/null 2>/dev/null && echo okay)
250
251ifeq ($(HDR_PROBE),)
252$(warning WARNING: Detected possible issues with include path.)
253$(warning WARNING: Please install kernel headers locally (make headers_install).)
254endif
255
256BTF_LLC_PROBE := $(shell $(LLC) -march=bpf -mattr=help 2>&1 | grep dwarfris)
257BTF_PAHOLE_PROBE := $(shell $(BTF_PAHOLE) --help 2>&1 | grep BTF)
258BTF_OBJCOPY_PROBE := $(shell $(LLVM_OBJCOPY) --help 2>&1 | grep -i 'usage.*llvm')
259BTF_LLVM_PROBE := $(shell echo "int main() { return 0; }" | \
260			  $(CLANG) -target bpf -O2 -g -c -x c - -o ./llvm_btf_verify.o; \
261			  $(LLVM_READELF) -S ./llvm_btf_verify.o | grep BTF; \
262			  /bin/rm -f ./llvm_btf_verify.o)
263
264BPF_EXTRA_CFLAGS += -fno-stack-protector
265ifneq ($(BTF_LLVM_PROBE),)
266	BPF_EXTRA_CFLAGS += -g
267else
268ifneq ($(and $(BTF_LLC_PROBE),$(BTF_PAHOLE_PROBE),$(BTF_OBJCOPY_PROBE)),)
269	BPF_EXTRA_CFLAGS += -g
270	LLC_FLAGS += -mattr=dwarfris
271	DWARF2BTF = y
272endif
273endif
274endif
275
276# Trick to allow make to be run from this directory
277all:
278	$(MAKE) -C ../../ M=$(CURDIR) BPF_SAMPLES_PATH=$(CURDIR)
279
280clean:
281	$(MAKE) -C ../../ M=$(CURDIR) clean
282	@find $(CURDIR) -type f -name '*~' -delete
283	@$(RM) -r $(CURDIR)/libbpf $(CURDIR)/bpftool
284
285$(LIBBPF): $(wildcard $(LIBBPF_SRC)/*.[ch] $(LIBBPF_SRC)/Makefile) | $(LIBBPF_OUTPUT)
286# Fix up variables inherited from Kbuild that tools/ build system won't like
287	$(MAKE) -C $(LIBBPF_SRC) RM='rm -rf' EXTRA_CFLAGS="$(TPROGS_CFLAGS)" \
288		LDFLAGS=$(TPROGS_LDFLAGS) srctree=$(BPF_SAMPLES_PATH)/../../ \
289		O= OUTPUT=$(LIBBPF_OUTPUT)/ DESTDIR=$(LIBBPF_DESTDIR) prefix= \
290		$@ install_headers
291
292BPFTOOLDIR := $(TOOLS_PATH)/bpf/bpftool
293BPFTOOL_OUTPUT := $(abspath $(BPF_SAMPLES_PATH))/bpftool
294BPFTOOL := $(BPFTOOL_OUTPUT)/bpftool
295$(BPFTOOL): $(LIBBPF) $(wildcard $(BPFTOOLDIR)/*.[ch] $(BPFTOOLDIR)/Makefile) | $(BPFTOOL_OUTPUT)
296	    $(MAKE) -C $(BPFTOOLDIR) srctree=$(BPF_SAMPLES_PATH)/../../ \
297		OUTPUT=$(BPFTOOL_OUTPUT)/ \
298		LIBBPF_OUTPUT=$(LIBBPF_OUTPUT)/ \
299		LIBBPF_DESTDIR=$(LIBBPF_DESTDIR)/
300
301$(LIBBPF_OUTPUT) $(BPFTOOL_OUTPUT):
302	$(call msg,MKDIR,$@)
303	$(Q)mkdir -p $@
304
305$(obj)/syscall_nrs.h:	$(obj)/syscall_nrs.s FORCE
306	$(call filechk,offsets,__SYSCALL_NRS_H__)
307
308targets += syscall_nrs.s
309clean-files += syscall_nrs.h
310
311FORCE:
312
313
314# Verify LLVM compiler tools are available and bpf target is supported by llc
315.PHONY: verify_cmds verify_target_bpf $(CLANG) $(LLC)
316
317verify_cmds: $(CLANG) $(LLC)
318	@for TOOL in $^ ; do \
319		if ! (which -- "$${TOOL}" > /dev/null 2>&1); then \
320			echo "*** ERROR: Cannot find LLVM tool $${TOOL}" ;\
321			exit 1; \
322		else true; fi; \
323	done
324
325verify_target_bpf: verify_cmds
326	@if ! (${LLC} -march=bpf -mattr=help > /dev/null 2>&1); then \
327		echo "*** ERROR: LLVM (${LLC}) does not support 'bpf' target" ;\
328		echo "   NOTICE: LLVM version >= 3.7.1 required" ;\
329		exit 2; \
330	else true; fi
331
332$(BPF_SAMPLES_PATH)/*.c: verify_target_bpf $(LIBBPF)
333$(src)/*.c: verify_target_bpf $(LIBBPF)
334
335libbpf_hdrs: $(LIBBPF)
336$(obj)/$(TRACE_HELPERS) $(obj)/$(CGROUP_HELPERS) $(obj)/$(XDP_SAMPLE): | libbpf_hdrs
337
338.PHONY: libbpf_hdrs
339
340$(obj)/xdp_redirect_cpu_user.o: $(obj)/xdp_redirect_cpu.skel.h
341$(obj)/xdp_redirect_map_multi_user.o: $(obj)/xdp_redirect_map_multi.skel.h
342$(obj)/xdp_redirect_map_user.o: $(obj)/xdp_redirect_map.skel.h
343$(obj)/xdp_redirect_user.o: $(obj)/xdp_redirect.skel.h
344$(obj)/xdp_monitor_user.o: $(obj)/xdp_monitor.skel.h
345$(obj)/xdp_router_ipv4_user.o: $(obj)/xdp_router_ipv4.skel.h
346
347$(obj)/tracex5_kern.o: $(obj)/syscall_nrs.h
348$(obj)/hbm_out_kern.o: $(src)/hbm.h $(src)/hbm_kern.h
349$(obj)/hbm.o: $(src)/hbm.h
350$(obj)/hbm_edt_kern.o: $(src)/hbm.h $(src)/hbm_kern.h
351
352# Override includes for xdp_sample_user.o because $(srctree)/usr/include in
353# TPROGS_CFLAGS causes conflicts
354XDP_SAMPLE_CFLAGS += -Wall -O2 \
355		     -I$(src)/../../tools/include \
356		     -I$(src)/../../tools/include/uapi \
357		     -I$(LIBBPF_INCLUDE) \
358		     -I$(src)/../../tools/testing/selftests/bpf
359
360$(obj)/$(XDP_SAMPLE): TPROGS_CFLAGS = $(XDP_SAMPLE_CFLAGS)
361$(obj)/$(XDP_SAMPLE): $(src)/xdp_sample_user.h $(src)/xdp_sample_shared.h
362
363-include $(BPF_SAMPLES_PATH)/Makefile.target
364
365VMLINUX_BTF_PATHS ?= $(abspath $(if $(O),$(O)/vmlinux))				\
366		     $(abspath $(if $(KBUILD_OUTPUT),$(KBUILD_OUTPUT)/vmlinux))	\
367		     $(abspath ./vmlinux)
368VMLINUX_BTF ?= $(abspath $(firstword $(wildcard $(VMLINUX_BTF_PATHS))))
369
370$(obj)/vmlinux.h: $(VMLINUX_BTF) $(BPFTOOL)
371ifeq ($(VMLINUX_H),)
372	$(Q)$(BPFTOOL) btf dump file $(VMLINUX_BTF) format c > $@
373else
374	$(Q)cp "$(VMLINUX_H)" $@
375endif
376
377ifeq ($(VMLINUX_BTF),)
378	$(error Cannot find a vmlinux for VMLINUX_BTF at any of "$(VMLINUX_BTF_PATHS)",\
379		build the kernel or set VMLINUX_BTF variable)
380endif
381
382clean-files += vmlinux.h
383
384# Get Clang's default includes on this system, as opposed to those seen by
385# '-target bpf'. This fixes "missing" files on some architectures/distros,
386# such as asm/byteorder.h, asm/socket.h, asm/sockios.h, sys/cdefs.h etc.
387#
388# Use '-idirafter': Don't interfere with include mechanics except where the
389# build would have failed anyways.
390define get_sys_includes
391$(shell $(1) -v -E - </dev/null 2>&1 \
392        | sed -n '/<...> search starts here:/,/End of search list./{ s| \(/.*\)|-idirafter \1|p }') \
393$(shell $(1) -dM -E - </dev/null | grep '#define __riscv_xlen ' | sed 's/#define /-D/' | sed 's/ /=/')
394endef
395
396CLANG_SYS_INCLUDES = $(call get_sys_includes,$(CLANG))
397
398$(obj)/xdp_redirect_cpu.bpf.o: $(obj)/xdp_sample.bpf.o
399$(obj)/xdp_redirect_map_multi.bpf.o: $(obj)/xdp_sample.bpf.o
400$(obj)/xdp_redirect_map.bpf.o: $(obj)/xdp_sample.bpf.o
401$(obj)/xdp_redirect.bpf.o: $(obj)/xdp_sample.bpf.o
402$(obj)/xdp_monitor.bpf.o: $(obj)/xdp_sample.bpf.o
403$(obj)/xdp_router_ipv4.bpf.o: $(obj)/xdp_sample.bpf.o
404
405$(obj)/%.bpf.o: $(src)/%.bpf.c $(obj)/vmlinux.h $(src)/xdp_sample.bpf.h $(src)/xdp_sample_shared.h
406	@echo "  CLANG-BPF " $@
407	$(Q)$(CLANG) -g -O2 -target bpf -D__TARGET_ARCH_$(SRCARCH) \
408		-Wno-compare-distinct-pointer-types -I$(srctree)/include \
409		-I$(srctree)/samples/bpf -I$(srctree)/tools/include \
410		-I$(LIBBPF_INCLUDE) $(CLANG_SYS_INCLUDES) \
411		-c $(filter %.bpf.c,$^) -o $@
412
413LINKED_SKELS := xdp_redirect_cpu.skel.h xdp_redirect_map_multi.skel.h \
414		xdp_redirect_map.skel.h xdp_redirect.skel.h xdp_monitor.skel.h \
415		xdp_router_ipv4.skel.h
416clean-files += $(LINKED_SKELS)
417
418xdp_redirect_cpu.skel.h-deps := xdp_redirect_cpu.bpf.o xdp_sample.bpf.o
419xdp_redirect_map_multi.skel.h-deps := xdp_redirect_map_multi.bpf.o xdp_sample.bpf.o
420xdp_redirect_map.skel.h-deps := xdp_redirect_map.bpf.o xdp_sample.bpf.o
421xdp_redirect.skel.h-deps := xdp_redirect.bpf.o xdp_sample.bpf.o
422xdp_monitor.skel.h-deps := xdp_monitor.bpf.o xdp_sample.bpf.o
423xdp_router_ipv4.skel.h-deps := xdp_router_ipv4.bpf.o xdp_sample.bpf.o
424
425LINKED_BPF_SRCS := $(patsubst %.bpf.o,%.bpf.c,$(foreach skel,$(LINKED_SKELS),$($(skel)-deps)))
426
427BPF_SRCS_LINKED := $(notdir $(wildcard $(src)/*.bpf.c))
428BPF_OBJS_LINKED := $(patsubst %.bpf.c,$(obj)/%.bpf.o, $(BPF_SRCS_LINKED))
429BPF_SKELS_LINKED := $(addprefix $(obj)/,$(LINKED_SKELS))
430
431$(BPF_SKELS_LINKED): $(BPF_OBJS_LINKED) $(BPFTOOL)
432	@echo "  BPF GEN-OBJ " $(@:.skel.h=)
433	$(Q)$(BPFTOOL) gen object $(@:.skel.h=.lbpf.o) $(addprefix $(obj)/,$($(@F)-deps))
434	@echo "  BPF GEN-SKEL" $(@:.skel.h=)
435	$(Q)$(BPFTOOL) gen skeleton $(@:.skel.h=.lbpf.o) name $(notdir $(@:.skel.h=)) > $@
436
437# asm/sysreg.h - inline assembly used by it is incompatible with llvm.
438# But, there is no easy way to fix it, so just exclude it since it is
439# useless for BPF samples.
440# below we use long chain of commands, clang | opt | llvm-dis | llc,
441# to generate final object file. 'clang' compiles the source into IR
442# with native target, e.g., x64, arm64, etc. 'opt' does bpf CORE IR builtin
443# processing (llvm12) and IR optimizations. 'llvm-dis' converts
444# 'opt' output to IR, and finally 'llc' generates bpf byte code.
445$(obj)/%.o: $(src)/%.c
446	@echo "  CLANG-bpf " $@
447	$(Q)$(CLANG) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(BPF_EXTRA_CFLAGS) \
448		-I$(obj) -I$(srctree)/tools/testing/selftests/bpf/ \
449		-I$(LIBBPF_INCLUDE) \
450		-D__KERNEL__ -D__BPF_TRACING__ -Wno-unused-value -Wno-pointer-sign \
451		-D__TARGET_ARCH_$(SRCARCH) -Wno-compare-distinct-pointer-types \
452		-Wno-gnu-variable-sized-type-not-at-end \
453		-Wno-address-of-packed-member -Wno-tautological-compare \
454		-Wno-unknown-warning-option $(CLANG_ARCH_ARGS) \
455		-fno-asynchronous-unwind-tables \
456		-I$(srctree)/samples/bpf/ -include asm_goto_workaround.h \
457		-O2 -emit-llvm -Xclang -disable-llvm-passes -c $< -o - | \
458		$(OPT) -O2 -mtriple=bpf-pc-linux | $(LLVM_DIS) | \
459		$(LLC) -march=bpf $(LLC_FLAGS) -filetype=obj -o $@
460ifeq ($(DWARF2BTF),y)
461	$(BTF_PAHOLE) -J $@
462endif
463