From: Jiri Olsa <jolsa@kernel.org>
Date: Wed, 17 Nov 2021 11:41:14 -0800
Subject: selftests/bpf: Add btf_dedup case with duplicated structs within CU
Patch-mainline: v5.17-rc1
Git-commit: 9a49afe6f5a516eb33bec24be0f81cb35ca79445
References: jsc#PED-1368
Add an artificial minimal example simulating compilers producing two
different types within a single CU that correspond to identical struct
definitions.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211117194114.347675-2-andrii@kernel.org
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
---
tools/testing/selftests/bpf/prog_tests/btf_dedup_split.c | 113 +++++++++++++++
1 file changed, 113 insertions(+)
--- a/tools/testing/selftests/bpf/prog_tests/btf_dedup_split.c
+++ b/tools/testing/selftests/bpf/prog_tests/btf_dedup_split.c
@@ -314,6 +314,117 @@ cleanup:
btf__free(btf1);
}
+static void btf_add_dup_struct_in_cu(struct btf *btf, int start_id)
+{
+#define ID(n) (start_id + n)
+ btf__set_pointer_size(btf, 8); /* enforce 64-bit arch */
+
+ btf__add_int(btf, "int", 4, BTF_INT_SIGNED); /* [1] int */
+
+ btf__add_struct(btf, "s", 8); /* [2] struct s { */
+ btf__add_field(btf, "a", ID(3), 0, 0); /* struct anon a; */
+ btf__add_field(btf, "b", ID(4), 0, 0); /* struct anon b; */
+ /* } */
+
+ btf__add_struct(btf, "(anon)", 8); /* [3] struct anon { */
+ btf__add_field(btf, "f1", ID(1), 0, 0); /* int f1; */
+ btf__add_field(btf, "f2", ID(1), 32, 0); /* int f2; */
+ /* } */
+
+ btf__add_struct(btf, "(anon)", 8); /* [4] struct anon { */
+ btf__add_field(btf, "f1", ID(1), 0, 0); /* int f1; */
+ btf__add_field(btf, "f2", ID(1), 32, 0); /* int f2; */
+ /* } */
+#undef ID
+}
+
+static void test_split_dup_struct_in_cu()
+{
+ struct btf *btf1, *btf2;
+ int err;
+
+ /* generate the base data.. */
+ btf1 = btf__new_empty();
+ if (!ASSERT_OK_PTR(btf1, "empty_main_btf"))
+ return;
+
+ btf_add_dup_struct_in_cu(btf1, 0);
+
+ VALIDATE_RAW_BTF(
+ btf1,
+ "[1] INT 'int' size=4 bits_offset=0 nr_bits=32 encoding=SIGNED",
+ "[2] STRUCT 's' size=8 vlen=2\n"
+ "\t'a' type_id=3 bits_offset=0\n"
+ "\t'b' type_id=4 bits_offset=0",
+ "[3] STRUCT '(anon)' size=8 vlen=2\n"
+ "\t'f1' type_id=1 bits_offset=0\n"
+ "\t'f2' type_id=1 bits_offset=32",
+ "[4] STRUCT '(anon)' size=8 vlen=2\n"
+ "\t'f1' type_id=1 bits_offset=0\n"
+ "\t'f2' type_id=1 bits_offset=32");
+
+ /* ..dedup them... */
+ err = btf__dedup(btf1, NULL, NULL);
+ if (!ASSERT_OK(err, "btf_dedup"))
+ goto cleanup;
+
+ VALIDATE_RAW_BTF(
+ btf1,
+ "[1] INT 'int' size=4 bits_offset=0 nr_bits=32 encoding=SIGNED",
+ "[2] STRUCT 's' size=8 vlen=2\n"
+ "\t'a' type_id=3 bits_offset=0\n"
+ "\t'b' type_id=3 bits_offset=0",
+ "[3] STRUCT '(anon)' size=8 vlen=2\n"
+ "\t'f1' type_id=1 bits_offset=0\n"
+ "\t'f2' type_id=1 bits_offset=32");
+
+ /* and add the same data on top of it */
+ btf2 = btf__new_empty_split(btf1);
+ if (!ASSERT_OK_PTR(btf2, "empty_split_btf"))
+ goto cleanup;
+
+ btf_add_dup_struct_in_cu(btf2, 3);
+
+ VALIDATE_RAW_BTF(
+ btf2,
+ "[1] INT 'int' size=4 bits_offset=0 nr_bits=32 encoding=SIGNED",
+ "[2] STRUCT 's' size=8 vlen=2\n"
+ "\t'a' type_id=3 bits_offset=0\n"
+ "\t'b' type_id=3 bits_offset=0",
+ "[3] STRUCT '(anon)' size=8 vlen=2\n"
+ "\t'f1' type_id=1 bits_offset=0\n"
+ "\t'f2' type_id=1 bits_offset=32",
+ "[4] INT 'int' size=4 bits_offset=0 nr_bits=32 encoding=SIGNED",
+ "[5] STRUCT 's' size=8 vlen=2\n"
+ "\t'a' type_id=6 bits_offset=0\n"
+ "\t'b' type_id=7 bits_offset=0",
+ "[6] STRUCT '(anon)' size=8 vlen=2\n"
+ "\t'f1' type_id=4 bits_offset=0\n"
+ "\t'f2' type_id=4 bits_offset=32",
+ "[7] STRUCT '(anon)' size=8 vlen=2\n"
+ "\t'f1' type_id=4 bits_offset=0\n"
+ "\t'f2' type_id=4 bits_offset=32");
+
+ err = btf__dedup(btf2, NULL, NULL);
+ if (!ASSERT_OK(err, "btf_dedup"))
+ goto cleanup;
+
+ /* after dedup it should match the original data */
+ VALIDATE_RAW_BTF(
+ btf2,
+ "[1] INT 'int' size=4 bits_offset=0 nr_bits=32 encoding=SIGNED",
+ "[2] STRUCT 's' size=8 vlen=2\n"
+ "\t'a' type_id=3 bits_offset=0\n"
+ "\t'b' type_id=3 bits_offset=0",
+ "[3] STRUCT '(anon)' size=8 vlen=2\n"
+ "\t'f1' type_id=1 bits_offset=0\n"
+ "\t'f2' type_id=1 bits_offset=32");
+
+cleanup:
+ btf__free(btf2);
+ btf__free(btf1);
+}
+
void test_btf_dedup_split()
{
if (test__start_subtest("split_simple"))
@@ -322,4 +433,6 @@ void test_btf_dedup_split()
test_split_struct_duped();
if (test__start_subtest("split_fwd_resolve"))
test_split_fwd_resolve();
+ if (test__start_subtest("split_dup_struct_in_cu"))
+ test_split_dup_struct_in_cu();
}