new file mode 100644
@@ -0,0 +1,99 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2020 Facebook */
+#include <test_progs.h>
+#include <bpf/btf.h>
+
+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 = NULL;
+ 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);
+}
@@ -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; \
Add selftest validating ability to programmatically generate and then dump split BTF. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> --- .../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