From 99e18fad5ff79eea2ea9ec7e6d800b286552e005 Mon Sep 17 00:00:00 2001 From: Eduard Zingerman Date: Wed, 9 Nov 2022 16:26:11 +0200 Subject: selftests/bpf: Tests for btf_dedup_resolve_fwds Tests to verify the following behavior of `btf_dedup_resolve_fwds`: - remapping for struct forward declarations; - remapping for union forward declarations; - no remapping if forward declaration kind does not match similarly named struct or union declaration; - no remapping if forward declaration name is ambiguous; - base ids are considered for fwd resolution in split btf scenario. Signed-off-by: Eduard Zingerman Signed-off-by: Andrii Nakryiko Reviewed-by: Alan Maguire Link: https://lore.kernel.org/bpf/20221109142611.879983-4-eddyz87@gmail.com --- tools/testing/selftests/bpf/prog_tests/btf.c | 176 +++++++++++++++++++++ .../selftests/bpf/prog_tests/btf_dedup_split.c | 45 ++++-- 2 files changed, 206 insertions(+), 15 deletions(-) diff --git a/tools/testing/selftests/bpf/prog_tests/btf.c b/tools/testing/selftests/bpf/prog_tests/btf.c index c3e1cea9abae..95a2b80f0d17 100644 --- a/tools/testing/selftests/bpf/prog_tests/btf.c +++ b/tools/testing/selftests/bpf/prog_tests/btf.c @@ -7690,6 +7690,182 @@ static struct btf_dedup_test dedup_tests[] = { BTF_STR_SEC("\0e1\0e1_val\0td"), }, }, +{ + .descr = "dedup: standalone fwd declaration struct", + /* + * Verify that CU1:foo and CU2:foo would be unified and that + * typedef/ptr would be updated to point to CU1:foo. + * + * // CU 1: + * struct foo { int x; }; + * + * // CU 2: + * struct foo; + * typedef struct foo *foo_ptr; + */ + .input = { + .raw_types = { + /* CU 1 */ + BTF_STRUCT_ENC(NAME_NTH(1), 1, 4), /* [1] */ + BTF_MEMBER_ENC(NAME_NTH(2), 2, 0), + BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [2] */ + /* CU 2 */ + BTF_FWD_ENC(NAME_NTH(1), 0), /* [3] */ + BTF_PTR_ENC(3), /* [4] */ + BTF_TYPEDEF_ENC(NAME_NTH(3), 4), /* [5] */ + BTF_END_RAW, + }, + BTF_STR_SEC("\0foo\0x\0foo_ptr"), + }, + .expect = { + .raw_types = { + BTF_STRUCT_ENC(NAME_NTH(1), 1, 4), /* [1] */ + BTF_MEMBER_ENC(NAME_NTH(2), 2, 0), + BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [2] */ + BTF_PTR_ENC(1), /* [3] */ + BTF_TYPEDEF_ENC(NAME_NTH(3), 3), /* [4] */ + BTF_END_RAW, + }, + BTF_STR_SEC("\0foo\0x\0foo_ptr"), + }, +}, +{ + .descr = "dedup: standalone fwd declaration union", + /* + * Verify that CU1:foo and CU2:foo would be unified and that + * typedef/ptr would be updated to point to CU1:foo. + * Same as "dedup: standalone fwd declaration struct" but for unions. + * + * // CU 1: + * union foo { int x; }; + * + * // CU 2: + * union foo; + * typedef union foo *foo_ptr; + */ + .input = { + .raw_types = { + /* CU 1 */ + BTF_UNION_ENC(NAME_NTH(1), 1, 4), /* [1] */ + BTF_MEMBER_ENC(NAME_NTH(2), 2, 0), + BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [2] */ + /* CU 2 */ + BTF_FWD_ENC(NAME_TBD, 1), /* [3] */ + BTF_PTR_ENC(3), /* [4] */ + BTF_TYPEDEF_ENC(NAME_NTH(3), 4), /* [5] */ + BTF_END_RAW, + }, + BTF_STR_SEC("\0foo\0x\0foo_ptr"), + }, + .expect = { + .raw_types = { + BTF_UNION_ENC(NAME_NTH(1), 1, 4), /* [1] */ + BTF_MEMBER_ENC(NAME_NTH(2), 2, 0), + BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [2] */ + BTF_PTR_ENC(1), /* [3] */ + BTF_TYPEDEF_ENC(NAME_NTH(3), 3), /* [4] */ + BTF_END_RAW, + }, + BTF_STR_SEC("\0foo\0x\0foo_ptr"), + }, +}, +{ + .descr = "dedup: standalone fwd declaration wrong kind", + /* + * Negative test for btf_dedup_resolve_fwds: + * - CU1:foo is a struct, C2:foo is a union, thus CU2:foo is not deduped; + * - typedef/ptr should remain unchanged as well. + * + * // CU 1: + * struct foo { int x; }; + * + * // CU 2: + * union foo; + * typedef union foo *foo_ptr; + */ + .input = { + .raw_types = { + /* CU 1 */ + BTF_STRUCT_ENC(NAME_NTH(1), 1, 4), /* [1] */ + BTF_MEMBER_ENC(NAME_NTH(2), 2, 0), + BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [2] */ + /* CU 2 */ + BTF_FWD_ENC(NAME_NTH(3), 1), /* [3] */ + BTF_PTR_ENC(3), /* [4] */ + BTF_TYPEDEF_ENC(NAME_NTH(3), 4), /* [5] */ + BTF_END_RAW, + }, + BTF_STR_SEC("\0foo\0x\0foo_ptr"), + }, + .expect = { + .raw_types = { + /* CU 1 */ + BTF_STRUCT_ENC(NAME_NTH(1), 1, 4), /* [1] */ + BTF_MEMBER_ENC(NAME_NTH(2), 2, 0), + BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [2] */ + /* CU 2 */ + BTF_FWD_ENC(NAME_NTH(3), 1), /* [3] */ + BTF_PTR_ENC(3), /* [4] */ + BTF_TYPEDEF_ENC(NAME_NTH(3), 4), /* [5] */ + BTF_END_RAW, + }, + BTF_STR_SEC("\0foo\0x\0foo_ptr"), + }, +}, +{ + .descr = "dedup: standalone fwd declaration name conflict", + /* + * Negative test for btf_dedup_resolve_fwds: + * - two candidates for CU2:foo dedup, thus it is unchanged; + * - typedef/ptr should remain unchanged as well. + * + * // CU 1: + * struct foo { int x; }; + * + * // CU 2: + * struct foo; + * typedef struct foo *foo_ptr; + * + * // CU 3: + * struct foo { int x; int y; }; + */ + .input = { + .raw_types = { + /* CU 1 */ + BTF_STRUCT_ENC(NAME_NTH(1), 1, 4), /* [1] */ + BTF_MEMBER_ENC(NAME_NTH(2), 2, 0), + BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [2] */ + /* CU 2 */ + BTF_FWD_ENC(NAME_NTH(1), 0), /* [3] */ + BTF_PTR_ENC(3), /* [4] */ + BTF_TYPEDEF_ENC(NAME_NTH(4), 4), /* [5] */ + /* CU 3 */ + BTF_STRUCT_ENC(NAME_NTH(1), 2, 8), /* [6] */ + BTF_MEMBER_ENC(NAME_NTH(2), 2, 0), + BTF_MEMBER_ENC(NAME_NTH(3), 2, 0), + BTF_END_RAW, + }, + BTF_STR_SEC("\0foo\0x\0y\0foo_ptr"), + }, + .expect = { + .raw_types = { + /* CU 1 */ + BTF_STRUCT_ENC(NAME_NTH(1), 1, 4), /* [1] */ + BTF_MEMBER_ENC(NAME_NTH(2), 2, 0), + BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [2] */ + /* CU 2 */ + BTF_FWD_ENC(NAME_NTH(1), 0), /* [3] */ + BTF_PTR_ENC(3), /* [4] */ + BTF_TYPEDEF_ENC(NAME_NTH(4), 4), /* [5] */ + /* CU 3 */ + BTF_STRUCT_ENC(NAME_NTH(1), 2, 8), /* [6] */ + BTF_MEMBER_ENC(NAME_NTH(2), 2, 0), + BTF_MEMBER_ENC(NAME_NTH(3), 2, 0), + BTF_END_RAW, + }, + BTF_STR_SEC("\0foo\0x\0y\0foo_ptr"), + }, +}, }; static int btf_type_size(const struct btf_type *t) diff --git a/tools/testing/selftests/bpf/prog_tests/btf_dedup_split.c b/tools/testing/selftests/bpf/prog_tests/btf_dedup_split.c index 90aac437576d..d9024c7a892a 100644 --- a/tools/testing/selftests/bpf/prog_tests/btf_dedup_split.c +++ b/tools/testing/selftests/bpf/prog_tests/btf_dedup_split.c @@ -141,6 +141,10 @@ static void test_split_fwd_resolve() { btf__add_field(btf1, "f2", 3, 64, 0); /* struct s2 *f2; */ /* } */ btf__add_struct(btf1, "s2", 4); /* [5] struct s2 { */ + btf__add_field(btf1, "f1", 1, 0, 0); /* int f1; */ + /* } */ + /* keep this not a part of type the graph to test btf_dedup_resolve_fwds */ + btf__add_struct(btf1, "s3", 4); /* [6] struct s3 { */ btf__add_field(btf1, "f1", 1, 0, 0); /* int f1; */ /* } */ @@ -153,20 +157,24 @@ static void test_split_fwd_resolve() { "\t'f1' type_id=2 bits_offset=0\n" "\t'f2' type_id=3 bits_offset=64", "[5] STRUCT 's2' size=4 vlen=1\n" + "\t'f1' type_id=1 bits_offset=0", + "[6] STRUCT 's3' size=4 vlen=1\n" "\t'f1' type_id=1 bits_offset=0"); btf2 = btf__new_empty_split(btf1); if (!ASSERT_OK_PTR(btf2, "empty_split_btf")) goto cleanup; - btf__add_int(btf2, "int", 4, BTF_INT_SIGNED); /* [6] int */ - btf__add_ptr(btf2, 10); /* [7] ptr to struct s1 */ - btf__add_fwd(btf2, "s2", BTF_FWD_STRUCT); /* [8] fwd for struct s2 */ - btf__add_ptr(btf2, 8); /* [9] ptr to fwd struct s2 */ - btf__add_struct(btf2, "s1", 16); /* [10] struct s1 { */ - btf__add_field(btf2, "f1", 7, 0, 0); /* struct s1 *f1; */ - btf__add_field(btf2, "f2", 9, 64, 0); /* struct s2 *f2; */ + btf__add_int(btf2, "int", 4, BTF_INT_SIGNED); /* [7] int */ + btf__add_ptr(btf2, 11); /* [8] ptr to struct s1 */ + btf__add_fwd(btf2, "s2", BTF_FWD_STRUCT); /* [9] fwd for struct s2 */ + btf__add_ptr(btf2, 9); /* [10] ptr to fwd struct s2 */ + btf__add_struct(btf2, "s1", 16); /* [11] struct s1 { */ + btf__add_field(btf2, "f1", 8, 0, 0); /* struct s1 *f1; */ + btf__add_field(btf2, "f2", 10, 64, 0); /* struct s2 *f2; */ /* } */ + btf__add_fwd(btf2, "s3", BTF_FWD_STRUCT); /* [12] fwd for struct s3 */ + btf__add_ptr(btf2, 12); /* [13] ptr to struct s1 */ VALIDATE_RAW_BTF( btf2, @@ -178,13 +186,17 @@ static void test_split_fwd_resolve() { "\t'f2' type_id=3 bits_offset=64", "[5] STRUCT 's2' size=4 vlen=1\n" "\t'f1' type_id=1 bits_offset=0", - "[6] INT 'int' size=4 bits_offset=0 nr_bits=32 encoding=SIGNED", - "[7] PTR '(anon)' type_id=10", - "[8] FWD 's2' fwd_kind=struct", - "[9] PTR '(anon)' type_id=8", - "[10] STRUCT 's1' size=16 vlen=2\n" - "\t'f1' type_id=7 bits_offset=0\n" - "\t'f2' type_id=9 bits_offset=64"); + "[6] STRUCT 's3' size=4 vlen=1\n" + "\t'f1' type_id=1 bits_offset=0", + "[7] INT 'int' size=4 bits_offset=0 nr_bits=32 encoding=SIGNED", + "[8] PTR '(anon)' type_id=11", + "[9] FWD 's2' fwd_kind=struct", + "[10] PTR '(anon)' type_id=9", + "[11] STRUCT 's1' size=16 vlen=2\n" + "\t'f1' type_id=8 bits_offset=0\n" + "\t'f2' type_id=10 bits_offset=64", + "[12] FWD 's3' fwd_kind=struct", + "[13] PTR '(anon)' type_id=12"); err = btf__dedup(btf2, NULL); if (!ASSERT_OK(err, "btf_dedup")) @@ -199,7 +211,10 @@ static void test_split_fwd_resolve() { "\t'f1' type_id=2 bits_offset=0\n" "\t'f2' type_id=3 bits_offset=64", "[5] STRUCT 's2' size=4 vlen=1\n" - "\t'f1' type_id=1 bits_offset=0"); + "\t'f1' type_id=1 bits_offset=0", + "[6] STRUCT 's3' size=4 vlen=1\n" + "\t'f1' type_id=1 bits_offset=0", + "[7] PTR '(anon)' type_id=6"); cleanup: btf__free(btf2); -- cgit v1.2.3