From 197389da2fbfbc3cefb229268c32d858d9575c96 Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Wed, 4 Nov 2020 20:33:55 -0800 Subject: [PATCH] selftests/bpf: Add split BTF basic test Add selftest validating ability to programmatically generate and then dump split BTF. Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Acked-by: Song Liu Link: https://lore.kernel.org/bpf/20201105043402.2530976-6-andrii@kernel.org --- tools/testing/selftests/bpf/prog_tests/btf_split.c | 99 ++++++++++++++++++++++ tools/testing/selftests/bpf/test_progs.h | 11 +++ 2 files changed, 110 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/btf_split.c diff --git a/tools/testing/selftests/bpf/prog_tests/btf_split.c b/tools/testing/selftests/bpf/prog_tests/btf_split.c new file mode 100644 index 0000000..ca7c2a9 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/btf_split.c @@ -0,0 +1,99 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2020 Facebook */ +#include +#include + +static char *dump_buf; +static size_t dump_buf_sz; +static FILE *dump_buf_file; + +static void btf_dump_printf(void *ctx, const char *fmt, va_list args) +{ + vfprintf(ctx, fmt, args); +} + +void test_btf_split() { + struct btf_dump_opts opts; + struct btf_dump *d = NULL; + const struct btf_type *t; + struct btf *btf1, *btf2; + int str_off, i, err; + + btf1 = btf__new_empty(); + if (!ASSERT_OK_PTR(btf1, "empty_main_btf")) + return; + + btf__set_pointer_size(btf1, 8); /* enforce 64-bit arch */ + + btf__add_int(btf1, "int", 4, BTF_INT_SIGNED); /* [1] int */ + btf__add_ptr(btf1, 1); /* [2] ptr to int */ + + btf__add_struct(btf1, "s1", 4); /* [3] struct s1 { */ + btf__add_field(btf1, "f1", 1, 0, 0); /* int f1; */ + /* } */ + + btf2 = btf__new_empty_split(btf1); + if (!ASSERT_OK_PTR(btf2, "empty_split_btf")) + goto cleanup; + + /* pointer size should be "inherited" from main BTF */ + ASSERT_EQ(btf__pointer_size(btf2), 8, "inherit_ptr_sz"); + + str_off = btf__find_str(btf2, "int"); + ASSERT_NEQ(str_off, -ENOENT, "str_int_missing"); + + t = btf__type_by_id(btf2, 1); + if (!ASSERT_OK_PTR(t, "int_type")) + goto cleanup; + ASSERT_EQ(btf_is_int(t), true, "int_kind"); + ASSERT_STREQ(btf__str_by_offset(btf2, t->name_off), "int", "int_name"); + + btf__add_struct(btf2, "s2", 16); /* [4] struct s2 { */ + btf__add_field(btf2, "f1", 3, 0, 0); /* struct s1 f1; */ + btf__add_field(btf2, "f2", 1, 32, 0); /* int f2; */ + btf__add_field(btf2, "f3", 2, 64, 0); /* int *f3; */ + /* } */ + + t = btf__type_by_id(btf1, 4); + ASSERT_NULL(t, "split_type_in_main"); + + t = btf__type_by_id(btf2, 4); + if (!ASSERT_OK_PTR(t, "split_struct_type")) + goto cleanup; + ASSERT_EQ(btf_is_struct(t), true, "split_struct_kind"); + ASSERT_EQ(btf_vlen(t), 3, "split_struct_vlen"); + ASSERT_STREQ(btf__str_by_offset(btf2, t->name_off), "s2", "split_struct_name"); + + /* BTF-to-C dump of split BTF */ + dump_buf_file = open_memstream(&dump_buf, &dump_buf_sz); + if (!ASSERT_OK_PTR(dump_buf_file, "dump_memstream")) + return; + opts.ctx = dump_buf_file; + d = btf_dump__new(btf2, NULL, &opts, btf_dump_printf); + if (!ASSERT_OK_PTR(d, "btf_dump__new")) + goto cleanup; + for (i = 1; i <= btf__get_nr_types(btf2); i++) { + err = btf_dump__dump_type(d, i); + ASSERT_OK(err, "dump_type_ok"); + } + fflush(dump_buf_file); + dump_buf[dump_buf_sz] = 0; /* some libc implementations don't do this */ + ASSERT_STREQ(dump_buf, +"struct s1 {\n" +" int f1;\n" +"};\n" +"\n" +"struct s2 {\n" +" struct s1 f1;\n" +" int f2;\n" +" int *f3;\n" +"};\n\n", "c_dump"); + +cleanup: + if (dump_buf_file) + fclose(dump_buf_file); + free(dump_buf); + btf_dump__free(d); + btf__free(btf1); + btf__free(btf2); +} diff --git a/tools/testing/selftests/bpf/test_progs.h b/tools/testing/selftests/bpf/test_progs.h index 238f5f6..d6b1485 100644 --- a/tools/testing/selftests/bpf/test_progs.h +++ b/tools/testing/selftests/bpf/test_progs.h @@ -141,6 +141,17 @@ extern int test__join_cgroup(const char *path); ___ok; \ }) +#define ASSERT_NEQ(actual, expected, name) ({ \ + static int duration = 0; \ + 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) ({ \ static int duration = 0; \ const char *___act = actual; \ -- 2.7.4