From: Jiri Olsa <jolsa@kernel.org>
Date: Sat, 11 Jul 2020 23:53:29 +0200
Subject: selftests/bpf: Add test for resolve_btfids
Patch-mainline: v5.9-rc1
Git-commit: cc15a20d5f3abc3cbd7911b70156b7b9e2bc7d41
References: bsc#1177028
Adding resolve_btfids test under test_progs suite.
It's possible to use btf_ids.h header and its logic in
user space application, so we can add easy test for it.
The test defines BTF_ID_LIST and checks it gets properly
resolved.
For this reason the test_progs binary (and other binaries
that use TRUNNER* macros) is processed with resolve_btfids
tool, which resolves BTF IDs in .BTF_ids section. The BTF
data are taken from btf_data.o object rceated from
progs/btf_data.c.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200711215329.41165-10-jolsa@kernel.org
Acked-by: Gary Lin <glin@suse.com>
---
tools/testing/selftests/bpf/Makefile | 15 ++
tools/testing/selftests/bpf/prog_tests/resolve_btfids.c | 111 ++++++++++++++++
tools/testing/selftests/bpf/progs/btf_data.c | 50 +++++++
3 files changed, 175 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/bpf/prog_tests/resolve_btfids.c
create mode 100644 tools/testing/selftests/bpf/progs/btf_data.c
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -105,6 +105,7 @@ SCRATCH_DIR := $(OUTPUT)/tools
BUILD_DIR := $(SCRATCH_DIR)/build
INCLUDE_DIR := $(SCRATCH_DIR)/include
BPFOBJ := $(BUILD_DIR)/libbpf/libbpf.a
+RESOLVE_BTFIDS := $(BUILD_DIR)/resolve_btfids/resolve_btfids
# Define simple and short `make test_progs`, `make test_sysctl`, etc targets
# to build individual tests.
@@ -171,7 +172,7 @@ $(BPFOBJ): $(wildcard $(BPFDIR)/*.[ch] $
$(Q)$(MAKE) $(submake_extras) -C $(BPFDIR) OUTPUT=$(BUILD_DIR)/libbpf/ \
DESTDIR=$(SCRATCH_DIR) prefix= all install_headers
-$(BUILD_DIR)/libbpf $(BUILD_DIR)/bpftool $(INCLUDE_DIR):
+$(BUILD_DIR)/libbpf $(BUILD_DIR)/bpftool $(BUILD_DIR)/resolve_btfids $(INCLUDE_DIR):
$(call msg,MKDIR,,$@)
mkdir -p $@
@@ -184,6 +185,16 @@ else
cp "$(VMLINUX_H)" $@
endif
+$(RESOLVE_BTFIDS): $(BPFOBJ) | $(BUILD_DIR)/resolve_btfids \
+ $(TOOLSDIR)/bpf/resolve_btfids/main.c \
+ $(TOOLSDIR)/lib/rbtree.c \
+ $(TOOLSDIR)/lib/zalloc.c \
+ $(TOOLSDIR)/lib/string.c \
+ $(TOOLSDIR)/lib/ctype.c \
+ $(TOOLSDIR)/lib/str_error_r.c
+ $(Q)$(MAKE) $(submake_extras) -C $(TOOLSDIR)/bpf/resolve_btfids \
+ OUTPUT=$(BUILD_DIR)/resolve_btfids/ BPFOBJ=$(BPFOBJ)
+
# 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.
@@ -346,9 +357,11 @@ endif
$(OUTPUT)/$(TRUNNER_BINARY): $(TRUNNER_TEST_OBJS) \
$(TRUNNER_EXTRA_OBJS) $$(BPFOBJ) \
+ $(RESOLVE_BTFIDS) \
| $(TRUNNER_BINARY)-extras
$$(call msg,BINARY,,$$@)
$$(CC) $$(CFLAGS) $$(filter %.a %.o,$$^) $$(LDLIBS) -o $$@
+ $(RESOLVE_BTFIDS) --no-fail --btf btf_data.o $$@
endef
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/resolve_btfids.c
@@ -0,0 +1,111 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/err.h>
+#include <string.h>
+#include <bpf/btf.h>
+#include <bpf/libbpf.h>
+#include <linux/btf.h>
+#include <linux/kernel.h>
+#include <linux/btf_ids.h>
+#include "test_progs.h"
+
+static int duration;
+
+struct symbol {
+ const char *name;
+ int type;
+ int id;
+};
+
+struct symbol test_symbols[] = {
+ { "unused", BTF_KIND_UNKN, 0 },
+ { "S", BTF_KIND_TYPEDEF, -1 },
+ { "T", BTF_KIND_TYPEDEF, -1 },
+ { "U", BTF_KIND_TYPEDEF, -1 },
+ { "S", BTF_KIND_STRUCT, -1 },
+ { "U", BTF_KIND_UNION, -1 },
+ { "func", BTF_KIND_FUNC, -1 },
+};
+
+BTF_ID_LIST(test_list)
+BTF_ID_UNUSED
+BTF_ID(typedef, S)
+BTF_ID(typedef, T)
+BTF_ID(typedef, U)
+BTF_ID(struct, S)
+BTF_ID(union, U)
+BTF_ID(func, func)
+
+static int
+__resolve_symbol(struct btf *btf, int type_id)
+{
+ const struct btf_type *type;
+ const char *str;
+ unsigned int i;
+
+ type = btf__type_by_id(btf, type_id);
+ if (!type) {
+ PRINT_FAIL("Failed to get type for ID %d\n", type_id);
+ return -1;
+ }
+
+ for (i = 0; i < ARRAY_SIZE(test_symbols); i++) {
+ if (test_symbols[i].id != -1)
+ continue;
+
+ if (BTF_INFO_KIND(type->info) != test_symbols[i].type)
+ continue;
+
+ str = btf__name_by_offset(btf, type->name_off);
+ if (!str) {
+ PRINT_FAIL("Failed to get name for BTF ID %d\n", type_id);
+ return -1;
+ }
+
+ if (!strcmp(str, test_symbols[i].name))
+ test_symbols[i].id = type_id;
+ }
+
+ return 0;
+}
+
+static int resolve_symbols(void)
+{
+ struct btf *btf;
+ int type_id;
+ __u32 nr;
+
+ btf = btf__parse_elf("btf_data.o", NULL);
+ if (CHECK(libbpf_get_error(btf), "resolve",
+ "Failed to load BTF from btf_data.o\n"))
+ return -1;
+
+ nr = btf__get_nr_types(btf);
+
+ for (type_id = 1; type_id <= nr; type_id++) {
+ if (__resolve_symbol(btf, type_id))
+ break;
+ }
+
+ btf__free(btf);
+ return 0;
+}
+
+int test_resolve_btfids(void)
+{
+ unsigned int i;
+ int ret = 0;
+
+ if (resolve_symbols())
+ return -1;
+
+ /* Check BTF_ID_LIST(test_list) IDs */
+ for (i = 0; i < ARRAY_SIZE(test_symbols) && !ret; i++) {
+ ret = CHECK(test_list[i] != test_symbols[i].id,
+ "id_check",
+ "wrong ID for %s (%d != %d)\n", test_symbols[i].name,
+ test_list[i], test_symbols[i].id);
+ }
+
+ return ret;
+}
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/btf_data.c
@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
+
+struct S {
+ int a;
+ int b;
+ int c;
+};
+
+union U {
+ int a;
+ int b;
+ int c;
+};
+
+struct S1 {
+ int a;
+ int b;
+ int c;
+};
+
+union U1 {
+ int a;
+ int b;
+ int c;
+};
+
+typedef int T;
+typedef int S;
+typedef int U;
+typedef int T1;
+typedef int S1;
+typedef int U1;
+
+struct root_struct {
+ S m_1;
+ T m_2;
+ U m_3;
+ S1 m_4;
+ T1 m_5;
+ U1 m_6;
+ struct S m_7;
+ struct S1 m_8;
+ union U m_9;
+ union U1 m_10;
+};
+
+int func(struct root_struct *root)
+{
+ return 0;
+}