Commit c0fa1b6c authored by Martin KaFai Lau's avatar Martin KaFai Lau Committed by Daniel Borkmann
Browse files

bpf: btf: Add BTF tests 

This patch tests the BTF loading, map_create with BTF
and the changes in libbpf.

-r: Raw tests that test raw crafted BTF data
-f: Test LLVM compiled bpf prog with BTF data
-g: Test BPF_OBJ_GET_INFO_BY_FD for btf_fd
-p: Test pretty print

The tools/testing/selftests/bpf/Makefile will probe
for BTF support in llc and pahole before generating
debug info (-g) and convert them to BTF.  You can supply
the BTF supported binary through the following make variables:
LLC, BTF_PAHOLE and LLVM_OBJCOPY.

LLC: The lastest llc with -mattr=dwarfris support for the bpf target.
     It is only in the master of the llvm repo for now.
BTF_PAHOLE: The modified pahole with BTF support:
	    https://github.com/iamkafai/pahole/tree/btf


	    To add a BTF section: "pahole -J bpf_prog.o"
LLVM_OBJCOPY: Any llvm-objcopy should do

Signed-off-by: default avatarMartin KaFai Lau <kafai@fb.com>
Acked-by: default avatarAlexei Starovoitov <ast@fb.com>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
parent 8a138aed

tools/testing/selftests/bpf/Makefile

+23 −3
Original line number Diff line number Diff line
@@ -24,14 +24,15 @@ urandom_read: urandom_read.c 
# Order correspond to 'make run_tests' order

TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test_progs \

	test_align test_verifier_log test_dev_cgroup test_tcpbpf_user \

	test_sock test_sock_addr

	test_sock test_sock_addr test_btf



TEST_GEN_FILES = test_pkt_access.o test_xdp.o test_l4lb.o test_tcp_estats.o test_obj_id.o \

	test_pkt_md_access.o test_xdp_redirect.o test_xdp_meta.o sockmap_parse_prog.o     \

	sockmap_verdict_prog.o dev_cgroup.o sample_ret0.o test_tracepoint.o \

	test_l4lb_noinline.o test_xdp_noinline.o test_stacktrace_map.o \

	sample_map_ret0.o test_tcpbpf_kern.o test_stacktrace_build_id.o \

	sockmap_tcp_msg_prog.o connect4_prog.o connect6_prog.o test_adjust_tail.o

	sockmap_tcp_msg_prog.o connect4_prog.o connect6_prog.o test_adjust_tail.o \

	test_btf_haskv.o test_btf_nokv.o



# Order correspond to 'make run_tests' order

TEST_PROGS := test_kmod.sh \
@@ -66,6 +67,8 @@ $(BPFOBJ): force 


CLANG ?= clang

LLC   ?= llc

LLVM_OBJCOPY ?= llvm-objcopy

BTF_PAHOLE ?= pahole



PROBE := $(shell $(LLC) -march=bpf -mcpu=probe -filetype=null /dev/null 2>&1)
@@ -83,9 +86,26 @@ CLANG_FLAGS = -I. -I./include/uapi -I../../../include/uapi \ 
$(OUTPUT)/test_l4lb_noinline.o: CLANG_FLAGS += -fno-inline

$(OUTPUT)/test_xdp_noinline.o: CLANG_FLAGS += -fno-inline



BTF_LLC_PROBE := $(shell $(LLC) -march=bpf -mattr=help |& grep dwarfris)

BTF_PAHOLE_PROBE := $(shell $(BTF_PAHOLE) --help |& grep BTF)

BTF_OBJCOPY_PROBE := $(shell $(LLVM_OBJCOPY) --version |& grep LLVM)



ifneq ($(BTF_LLC_PROBE),)

ifneq ($(BTF_PAHOLE_PROBE),)

ifneq ($(BTF_OBJCOPY_PROBE),)

	CLANG_FLAGS += -g

	LLC_FLAGS += -mattr=dwarfris

	DWARF2BTF = y

endif

endif

endif



$(OUTPUT)/%.o: %.c

	$(CLANG) $(CLANG_FLAGS) \

		 -O2 -target bpf -emit-llvm -c $< -o - |      \

	$(LLC) -march=bpf -mcpu=$(CPU) -filetype=obj -o $@

	$(LLC) -march=bpf -mcpu=$(CPU) $(LLC_FLAGS) -filetype=obj -o $@

ifeq ($(DWARF2BTF),y)

	$(BTF_PAHOLE) -J $@

endif



EXTRA_CLEAN := $(TEST_CUSTOM_PROGS)

tools/testing/selftests/bpf/test_btf.c

0 → 100644
+1669 −0

File added.

Preview size limit exceeded, changes collapsed.

tools/testing/selftests/bpf/test_btf_haskv.c

0 → 100644
+48 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 */

/* Copyright (c) 2018 Facebook */

#include <linux/bpf.h>

#include "bpf_helpers.h"



int _version SEC("version") = 1;



struct ipv_counts {

	unsigned int v4;

	unsigned int v6;

};



typedef int btf_map_key;

typedef struct ipv_counts btf_map_value;

btf_map_key dumm_key;

btf_map_value dummy_value;



struct bpf_map_def SEC("maps") btf_map = {

	.type = BPF_MAP_TYPE_ARRAY,

	.key_size = sizeof(int),

	.value_size = sizeof(struct ipv_counts),

	.max_entries = 4,

};



struct dummy_tracepoint_args {

	unsigned long long pad;

	struct sock *sock;

};



SEC("dummy_tracepoint")

int _dummy_tracepoint(struct dummy_tracepoint_args *arg)

{

	struct ipv_counts *counts;

	int key = 0;



	if (!arg->sock)

		return 0;



	counts = bpf_map_lookup_elem(&btf_map, &key);

	if (!counts)

		return 0;



	counts->v6++;



	return 0;

}



char _license[] SEC("license") = "GPL";

tools/testing/selftests/bpf/test_btf_nokv.c

0 → 100644
+43 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 */

/* Copyright (c) 2018 Facebook */

#include <linux/bpf.h>

#include "bpf_helpers.h"



int _version SEC("version") = 1;



struct ipv_counts {

	unsigned int v4;

	unsigned int v6;

};



struct bpf_map_def SEC("maps") btf_map = {

	.type = BPF_MAP_TYPE_ARRAY,

	.key_size = sizeof(int),

	.value_size = sizeof(struct ipv_counts),

	.max_entries = 4,

};



struct dummy_tracepoint_args {

	unsigned long long pad;

	struct sock *sock;

};



SEC("dummy_tracepoint")

int _dummy_tracepoint(struct dummy_tracepoint_args *arg)

{

	struct ipv_counts *counts;

	int key = 0;



	if (!arg->sock)

		return 0;



	counts = bpf_map_lookup_elem(&btf_map, &key);

	if (!counts)

		return 0;



	counts->v6++;



	return 0;

}



char _license[] SEC("license") = "GPL";

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