[v3,bpf-next,3/3] selftests/bpf: test BTF writing APIs

Message ID	20200929020533.711288-4-andriin@fb.com
State	Superseded
Headers	show Return-Path: <SRS0=pKMR=DG=vger.kernel.org=netdev-owner@kernel.org> From: Andrii Nakryiko <andriin@fb.com> To: <bpf@vger.kernel.org>, <netdev@vger.kernel.org>, <ast@fb.com>, <daniel@iogearbox.net> CC: <andrii.nakryiko@gmail.com>, <kernel-team@fb.com>, Andrii Nakryiko <andriin@fb.com>, Arnaldo Carvalho de Melo <acme@redhat.com>, John Fastabend <john.fastabend@gmail.com> Subject: [PATCH v3 bpf-next 3/3] selftests/bpf: test BTF writing APIs Date: Mon, 28 Sep 2020 19:05:32 -0700 Message-ID: <20200929020533.711288-4-andriin@fb.com> In-Reply-To: <20200929020533.711288-1-andriin@fb.com> References: <20200929020533.711288-1-andriin@fb.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain Precedence: bulk
Series	libbpf: BTF writer APIs \| expand [v3,bpf-next,0/3] libbpf: BTF writer APIs [v3,bpf-next,1/3] libbpf: add BTF writing APIs [v3,bpf-next,2/3] libbpf: add btf__str_by_offset() as a more generic variant of name_by_offset [v3,bpf-next,3/3] selftests/bpf: test BTF writing APIs

diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c index 2d0b1e12f50e..c25f49fad5a6 100644 --- a/tools/lib/bpf/btf.c +++ b/tools/lib/bpf/btf.c @@ -31,10 +31,10 @@ struct btf { __u32 raw_size; /* - * When BTF is loaded from ELF or raw memory it is stored - * in contiguous memory block, pointed to by raw_data pointer, and - * hdr, types_data, and strs_data point inside that memory region to - * respective parts of BTF representation: + * When BTF is loaded from an ELF or raw memory it is stored + * in a contiguous memory block. The hdr, type_data, and, strs_data + * point inside that memory region to their respective parts of BTF + * representation: * * +--------------------------------+ * | Header | Types | Strings | diff --git a/tools/testing/selftests/bpf/prog_tests/btf_write.c b/tools/testing/selftests/bpf/prog_tests/btf_write.c new file mode 100644 index 000000000000..88dce2cfa79b --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/btf_write.c @@ -0,0 +1,278 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2020 Facebook */ +#include <test_progs.h> +#include <bpf/btf.h> + +#define ASSERT_EQ(actual, expected, name) ({ \ + typeof(actual) ___act = (actual); \ + typeof(expected) ___exp = (expected); \ + bool ___ok = ___act == ___exp; \ + CHECK(!___ok, (name), \ + "unexpected %s: actual %lld != expected %lld\n", \ + (name), (long long)(___act), (long long)(___exp)); \ + ___ok; \ +}) + +#define ASSERT_STREQ(actual, expected, name) ({ \ + const char *___act = actual; \ + const char *___exp = expected; \ + bool ___ok = strcmp(___act, ___exp) == 0; \ + CHECK(!___ok, (name), \ + "unexpected %s: actual '%s' != expected '%s'\n", \ + (name), ___act, ___exp); \ + ___ok; \ +}) + +#define ASSERT_OK(res, name) ({ \ + long long ___res = (res); \ + bool ___ok = ___res == 0; \ + CHECK(!___ok, (name), "unexpected error: %lld\n", ___res); \ + ___ok; \ +}) + +#define ASSERT_ERR(res, name) ({ \ + long long ___res = (res); \ + bool ___ok = ___res < 0; \ + CHECK(!___ok, (name), "unexpected success: %lld\n", ___res); \ + ___ok; \ +}) + +static int duration = 0; + +void test_btf_write() { + const struct btf_var_secinfo *vi; + const struct btf_type *t; + const struct btf_member *m; + const struct btf_enum *v; + const struct btf_param *p; + struct btf *btf; + int id, err, str_off; + + btf = btf__new_empty(); + if (CHECK(IS_ERR(btf), "new_empty", "failed: %ld\n", PTR_ERR(btf))) + return; + + str_off = btf__find_str(btf, "int"); + ASSERT_EQ(str_off, -ENOENT, "int_str_missing_off"); + + str_off = btf__add_str(btf, "int"); + ASSERT_EQ(str_off, 1, "int_str_off"); + + str_off = btf__find_str(btf, "int"); + ASSERT_EQ(str_off, 1, "int_str_found_off"); + + /* BTF_KIND_INT */ + id = btf__add_int(btf, "int", 4, BTF_INT_SIGNED); + ASSERT_EQ(id, 1, "int_id"); + + t = btf__type_by_id(btf, 1); + /* should re-use previously added "int" string */ + ASSERT_EQ(t->name_off, str_off, "int_name_off"); + ASSERT_STREQ(btf__str_by_offset(btf, t->name_off), "int", "int_name"); + ASSERT_EQ(btf_kind(t), BTF_KIND_INT, "int_kind"); + ASSERT_EQ(t->size, 4, "int_sz"); + ASSERT_EQ(btf_int_encoding(t), BTF_INT_SIGNED, "int_enc"); + ASSERT_EQ(btf_int_bits(t), 32, "int_bits"); + + /* invalid int size */ + id = btf__add_int(btf, "bad sz int", 7, 0); + ASSERT_ERR(id, "int_bad_sz"); + /* invalid encoding */ + id = btf__add_int(btf, "bad enc int", 4, 123); + ASSERT_ERR(id, "int_bad_enc"); + /* NULL name */ + id = btf__add_int(btf, NULL, 4, 0); + ASSERT_ERR(id, "int_bad_null_name"); + /* empty name */ + id = btf__add_int(btf, "", 4, 0); + ASSERT_ERR(id, "int_bad_empty_name"); + + /* PTR/CONST/VOLATILE/RESTRICT */ + id = btf__add_ptr(btf, 1); + ASSERT_EQ(id, 2, "ptr_id"); + t = btf__type_by_id(btf, 2); + ASSERT_EQ(btf_kind(t), BTF_KIND_PTR, "ptr_kind"); + ASSERT_EQ(t->type, 1, "ptr_type"); + + id = btf__add_const(btf, 5); /* points forward to restrict */ + ASSERT_EQ(id, 3, "const_id"); + t = btf__type_by_id(btf, 3); + ASSERT_EQ(btf_kind(t), BTF_KIND_CONST, "const_kind"); + ASSERT_EQ(t->type, 5, "const_type"); + + id = btf__add_volatile(btf, 3); + ASSERT_EQ(id, 4, "volatile_id"); + t = btf__type_by_id(btf, 4); + ASSERT_EQ(btf_kind(t), BTF_KIND_VOLATILE, "volatile_kind"); + ASSERT_EQ(t->type, 3, "volatile_type"); + + id = btf__add_restrict(btf, 4); + ASSERT_EQ(id, 5, "restrict_id"); + t = btf__type_by_id(btf, 5); + ASSERT_EQ(btf_kind(t), BTF_KIND_RESTRICT, "restrict_kind"); + ASSERT_EQ(t->type, 4, "restrict_type"); + + /* ARRAY */ + id = btf__add_array(btf, 1, 2, 10); /* int *[10] */ + ASSERT_EQ(id, 6, "array_id"); + t = btf__type_by_id(btf, 6); + ASSERT_EQ(btf_kind(t), BTF_KIND_ARRAY, "array_kind"); + ASSERT_EQ(btf_array(t)->index_type, 1, "array_index_type"); + ASSERT_EQ(btf_array(t)->type, 2, "array_elem_type"); + ASSERT_EQ(btf_array(t)->nelems, 10, "array_nelems"); + + /* STRUCT */ + err = btf__add_field(btf, "field", 1, 0, 0); + ASSERT_ERR(err, "no_struct_field"); + id = btf__add_struct(btf, "s1", 8); + ASSERT_EQ(id, 7, "struct_id"); + err = btf__add_field(btf, "f1", 1, 0, 0); + ASSERT_OK(err, "f1_res"); + err = btf__add_field(btf, "f2", 1, 32, 16); + ASSERT_OK(err, "f2_res"); + + t = btf__type_by_id(btf, 7); + ASSERT_STREQ(btf__str_by_offset(btf, t->name_off), "s1", "struct_name"); + ASSERT_EQ(btf_kind(t), BTF_KIND_STRUCT, "struct_kind"); + ASSERT_EQ(btf_vlen(t), 2, "struct_vlen"); + ASSERT_EQ(btf_kflag(t), true, "struct_kflag"); + ASSERT_EQ(t->size, 8, "struct_sz"); + m = btf_members(t) + 0; + ASSERT_STREQ(btf__str_by_offset(btf, m->name_off), "f1", "f1_name"); + ASSERT_EQ(m->type, 1, "f1_type"); + ASSERT_EQ(btf_member_bit_offset(t, 0), 0, "f1_bit_off"); + ASSERT_EQ(btf_member_bitfield_size(t, 0), 0, "f1_bit_sz"); + m = btf_members(t) + 1; + ASSERT_STREQ(btf__str_by_offset(btf, m->name_off), "f2", "f2_name"); + ASSERT_EQ(m->type, 1, "f2_type"); + ASSERT_EQ(btf_member_bit_offset(t, 1), 32, "f2_bit_off"); + ASSERT_EQ(btf_member_bitfield_size(t, 1), 16, "f2_bit_sz"); + + /* UNION */ + id = btf__add_union(btf, "u1", 8); + ASSERT_EQ(id, 8, "union_id"); + + /* invalid, non-zero offset */ + err = btf__add_field(btf, "field", 1, 1, 0); + ASSERT_ERR(err, "no_struct_field"); + + err = btf__add_field(btf, "f1", 1, 0, 16); + ASSERT_OK(err, "f1_res"); + + t = btf__type_by_id(btf, 8); + ASSERT_STREQ(btf__str_by_offset(btf, t->name_off), "u1", "union_name"); + ASSERT_EQ(btf_kind(t), BTF_KIND_UNION, "union_kind"); + ASSERT_EQ(btf_vlen(t), 1, "union_vlen"); + ASSERT_EQ(btf_kflag(t), true, "union_kflag"); + ASSERT_EQ(t->size, 8, "union_sz"); + m = btf_members(t) + 0; + ASSERT_STREQ(btf__str_by_offset(btf, m->name_off), "f1", "f1_name"); + ASSERT_EQ(m->type, 1, "f1_type"); + ASSERT_EQ(btf_member_bit_offset(t, 0), 0, "f1_bit_off"); + ASSERT_EQ(btf_member_bitfield_size(t, 0), 16, "f1_bit_sz"); + + /* ENUM */ + id = btf__add_enum(btf, "e1", 4); + ASSERT_EQ(id, 9, "enum_id"); + err = btf__add_enum_value(btf, "v1", 1); + ASSERT_OK(err, "v1_res"); + err = btf__add_enum_value(btf, "v2", 2); + ASSERT_OK(err, "v2_res"); + + t = btf__type_by_id(btf, 9); + ASSERT_STREQ(btf__str_by_offset(btf, t->name_off), "e1", "enum_name"); + ASSERT_EQ(btf_kind(t), BTF_KIND_ENUM, "enum_kind"); + ASSERT_EQ(btf_vlen(t), 2, "enum_vlen"); + ASSERT_EQ(t->size, 4, "enum_sz"); + v = btf_enum(t) + 0; + ASSERT_STREQ(btf__str_by_offset(btf, v->name_off), "v1", "v1_name"); + ASSERT_EQ(v->val, 1, "v1_val"); + v = btf_enum(t) + 1; + ASSERT_STREQ(btf__str_by_offset(btf, v->name_off), "v2", "v2_name"); + ASSERT_EQ(v->val, 2, "v2_val"); + + /* FWDs */ + id = btf__add_fwd(btf, "struct_fwd", BTF_FWD_STRUCT); + ASSERT_EQ(id, 10, "struct_fwd_id"); + t = btf__type_by_id(btf, 10); + ASSERT_STREQ(btf__str_by_offset(btf, t->name_off), "struct_fwd", "fwd_name"); + ASSERT_EQ(btf_kind(t), BTF_KIND_FWD, "fwd_kind"); + ASSERT_EQ(btf_kflag(t), 0, "fwd_kflag"); + + id = btf__add_fwd(btf, "union_fwd", BTF_FWD_UNION); + ASSERT_EQ(id, 11, "union_fwd_id"); + t = btf__type_by_id(btf, 11); + ASSERT_STREQ(btf__str_by_offset(btf, t->name_off), "union_fwd", "fwd_name"); + ASSERT_EQ(btf_kind(t), BTF_KIND_FWD, "fwd_kind"); + ASSERT_EQ(btf_kflag(t), 1, "fwd_kflag"); + + id = btf__add_fwd(btf, "enum_fwd", BTF_FWD_ENUM); + ASSERT_EQ(id, 12, "enum_fwd_id"); + t = btf__type_by_id(btf, 12); + ASSERT_STREQ(btf__str_by_offset(btf, t->name_off), "enum_fwd", "fwd_name"); + ASSERT_EQ(btf_kind(t), BTF_KIND_ENUM, "enum_fwd_kind"); + ASSERT_EQ(btf_vlen(t), 0, "enum_fwd_kind"); + ASSERT_EQ(t->size, 4, "enum_fwd_sz"); + + /* TYPEDEF */ + id = btf__add_typedef(btf, "typedef1", 1); + ASSERT_EQ(id, 13, "typedef_fwd_id"); + t = btf__type_by_id(btf, 13); + ASSERT_STREQ(btf__str_by_offset(btf, t->name_off), "typedef1", "typedef_name"); + ASSERT_EQ(btf_kind(t), BTF_KIND_TYPEDEF, "typedef_kind"); + ASSERT_EQ(t->type, 1, "typedef_type"); + + /* FUNC & FUNC_PROTO */ + id = btf__add_func(btf, "func1", BTF_FUNC_GLOBAL, 15); + ASSERT_EQ(id, 14, "func_id"); + t = btf__type_by_id(btf, 14); + ASSERT_STREQ(btf__str_by_offset(btf, t->name_off), "func1", "func_name"); + ASSERT_EQ(t->type, 15, "func_type"); + ASSERT_EQ(btf_kind(t), BTF_KIND_FUNC, "func_kind"); + ASSERT_EQ(btf_vlen(t), BTF_FUNC_GLOBAL, "func_vlen"); + + id = btf__add_func_proto(btf, 1); + ASSERT_EQ(id, 15, "func_proto_id"); + err = btf__add_func_param(btf, "p1", 1); + ASSERT_OK(err, "p1_res"); + err = btf__add_func_param(btf, "p2", 2); + ASSERT_OK(err, "p2_res"); + + t = btf__type_by_id(btf, 15); + ASSERT_EQ(btf_kind(t), BTF_KIND_FUNC_PROTO, "func_proto_kind"); + ASSERT_EQ(btf_vlen(t), 2, "func_proto_vlen"); + ASSERT_EQ(t->type, 1, "func_proto_ret_type"); + p = btf_params(t) + 0; + ASSERT_STREQ(btf__str_by_offset(btf, p->name_off), "p1", "p1_name"); + ASSERT_EQ(p->type, 1, "p1_type"); + p = btf_params(t) + 1; + ASSERT_STREQ(btf__str_by_offset(btf, p->name_off), "p2", "p2_name"); + ASSERT_EQ(p->type, 2, "p2_type"); + + /* VAR */ + id = btf__add_var(btf, "var1", BTF_VAR_GLOBAL_ALLOCATED, 1); + ASSERT_EQ(id, 16, "var_id"); + t = btf__type_by_id(btf, 16); + ASSERT_STREQ(btf__str_by_offset(btf, t->name_off), "var1", "var_name"); + ASSERT_EQ(btf_kind(t), BTF_KIND_VAR, "var_kind"); + ASSERT_EQ(t->type, 1, "var_type"); + ASSERT_EQ(btf_var(t)->linkage, BTF_VAR_GLOBAL_ALLOCATED, "var_type"); + + /* DATASECT */ + id = btf__add_datasec(btf, "datasec1", 12); + ASSERT_EQ(id, 17, "datasec_id"); + err = btf__add_datasec_var_info(btf, 1, 4, 8); + ASSERT_OK(err, "v1_res"); + + t = btf__type_by_id(btf, 17); + ASSERT_STREQ(btf__str_by_offset(btf, t->name_off), "datasec1", "datasec_name"); + ASSERT_EQ(t->size, 12, "datasec_sz"); + ASSERT_EQ(btf_kind(t), BTF_KIND_DATASEC, "datasec_kind"); + ASSERT_EQ(btf_vlen(t), 1, "datasec_vlen"); + vi = btf_var_secinfos(t) + 0; + ASSERT_EQ(vi->type, 1, "v1_type"); + ASSERT_EQ(vi->offset, 4, "v1_off"); + ASSERT_EQ(vi->size, 8, "v1_sz"); + + btf__free(btf); +}

[v3,bpf-next,3/3] selftests/bpf: test BTF writing APIs

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Patch