Commit 232338fa authored by Andrii Nakryiko's avatar Andrii Nakryiko Committed by Alexei Starovoitov
Browse files

selftests/bpf: Add split BTF dedup selftests 



Add selftests validating BTF deduplication for split BTF case. Add a helper
macro that allows to validate entire BTF with raw BTF dump, not just
type-by-type. This saves tons of code and complexity.

Signed-off-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Acked-by: default avatarSong Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201105043402.2530976-11-andrii@kernel.org
parent 6b6e6b1d

tools/testing/selftests/bpf/btf_helpers.c

+59 −0
Original line number Diff line number Diff line
@@ -3,6 +3,8 @@ 
#include <stdio.h>

#include <errno.h>

#include <bpf/btf.h>

#include <bpf/libbpf.h>

#include "test_progs.h"



static const char * const btf_kind_str_mapping[] = {

	[BTF_KIND_UNKN]		= "UNKNOWN",
@@ -198,3 +200,60 @@ const char *btf_type_raw_dump(const struct btf *btf, int type_id) 


	return buf;

}



int btf_validate_raw(struct btf *btf, int nr_types, const char *exp_types[])

{

	int i;

	bool ok = true;



	ASSERT_EQ(btf__get_nr_types(btf), nr_types, "btf_nr_types");



	for (i = 1; i <= nr_types; i++) {

		if (!ASSERT_STREQ(btf_type_raw_dump(btf, i), exp_types[i - 1], "raw_dump"))

			ok = false;

	}



	return ok;

}



static void btf_dump_printf(void *ctx, const char *fmt, va_list args)

{

	vfprintf(ctx, fmt, args);

}



/* Print BTF-to-C dump into a local buffer and return string pointer back.

 * Buffer *will* be overwritten by subsequent btf_type_raw_dump() calls

 */

const char *btf_type_c_dump(const struct btf *btf)

{

	static char buf[16 * 1024];

	FILE *buf_file;

	struct btf_dump *d = NULL;

	struct btf_dump_opts opts = {};

	int err, i;



	buf_file = fmemopen(buf, sizeof(buf) - 1, "w");

	if (!buf_file) {

		fprintf(stderr, "Failed to open memstream: %d\n", errno);

		return NULL;

	}



	opts.ctx = buf_file;

	d = btf_dump__new(btf, NULL, &opts, btf_dump_printf);

	if (libbpf_get_error(d)) {

		fprintf(stderr, "Failed to create btf_dump instance: %ld\n", libbpf_get_error(d));

		return NULL;

	}



	for (i = 1; i <= btf__get_nr_types(btf); i++) {

		err = btf_dump__dump_type(d, i);

		if (err) {

			fprintf(stderr, "Failed to dump type [%d]: %d\n", i, err);

			return NULL;

		}

	}



	fflush(buf_file);

	fclose(buf_file);

	return buf;

}

tools/testing/selftests/bpf/btf_helpers.h

+7 −0
Original line number Diff line number Diff line
@@ -8,5 +8,12 @@ 


int fprintf_btf_type_raw(FILE *out, const struct btf *btf, __u32 id);

const char *btf_type_raw_dump(const struct btf *btf, int type_id);

int btf_validate_raw(struct btf *btf, int nr_types, const char *exp_types[]);



#define VALIDATE_RAW_BTF(btf, raw_types...)				\

	btf_validate_raw(btf,						\

			 sizeof((const char *[]){raw_types})/sizeof(void *),\

			 (const char *[]){raw_types})



const char *btf_type_c_dump(const struct btf *btf);

#endif

tools/testing/selftests/bpf/prog_tests/btf_dedup_split.c

0 → 100644
+325 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/* Copyright (c) 2020 Facebook */

#include <test_progs.h>

#include <bpf/btf.h>

#include "btf_helpers.h"



static void test_split_simple() {

	const struct btf_type *t;

	struct btf *btf1, *btf2;

	int str_off, 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; */

							/* } */



	VALIDATE_RAW_BTF(

		btf1,

		"[1] INT 'int' size=4 bits_offset=0 nr_bits=32 encoding=SIGNED",

		"[2] PTR '(anon)' type_id=1",

		"[3] STRUCT 's1' size=4 vlen=1\n"

		"\t'f1' type_id=1 bits_offset=0");



	ASSERT_STREQ(btf_type_c_dump(btf1), "\

struct s1 {\n\

	int f1;\n\

};\n\n", "c_dump");



	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", 6, 0, 0);		/*      struct s1 f1;	*/

	btf__add_field(btf2, "f2", 5, 32, 0);		/*      int f2;		*/

	btf__add_field(btf2, "f3", 2, 64, 0);		/*      int *f3;	*/

							/* } */



	/* duplicated int */

	btf__add_int(btf2, "int", 4, BTF_INT_SIGNED);	/* [5] int */



	/* duplicated struct s1 */

	btf__add_struct(btf2, "s1", 4);			/* [6] struct s1 { */

	btf__add_field(btf2, "f1", 5, 0, 0);		/*      int f1; */

							/* } */



	VALIDATE_RAW_BTF(

		btf2,

		"[1] INT 'int' size=4 bits_offset=0 nr_bits=32 encoding=SIGNED",

		"[2] PTR '(anon)' type_id=1",

		"[3] STRUCT 's1' size=4 vlen=1\n"

		"\t'f1' type_id=1 bits_offset=0",

		"[4] STRUCT 's2' size=16 vlen=3\n"

		"\t'f1' type_id=6 bits_offset=0\n"

		"\t'f2' type_id=5 bits_offset=32\n"

		"\t'f3' type_id=2 bits_offset=64",

		"[5] INT 'int' size=4 bits_offset=0 nr_bits=32 encoding=SIGNED",

		"[6] STRUCT 's1' size=4 vlen=1\n"

		"\t'f1' type_id=5 bits_offset=0");



	ASSERT_STREQ(btf_type_c_dump(btf2), "\

struct s1 {\n\

	int f1;\n\

};\n\

\n\

struct s1___2 {\n\

	int f1;\n\

};\n\

\n\

struct s2 {\n\

	struct s1___2 f1;\n\

	int f2;\n\

	int *f3;\n\

};\n\n", "c_dump");



	err = btf__dedup(btf2, NULL, NULL);

	if (!ASSERT_OK(err, "btf_dedup"))

		goto cleanup;



	VALIDATE_RAW_BTF(

		btf2,

		"[1] INT 'int' size=4 bits_offset=0 nr_bits=32 encoding=SIGNED",

		"[2] PTR '(anon)' type_id=1",

		"[3] STRUCT 's1' size=4 vlen=1\n"

		"\t'f1' type_id=1 bits_offset=0",

		"[4] STRUCT 's2' size=16 vlen=3\n"

		"\t'f1' type_id=3 bits_offset=0\n"

		"\t'f2' type_id=1 bits_offset=32\n"

		"\t'f3' type_id=2 bits_offset=64");



	ASSERT_STREQ(btf_type_c_dump(btf2), "\

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:

	btf__free(btf2);

	btf__free(btf1);

}



static void test_split_fwd_resolve() {

	struct btf *btf1, *btf2;

	int 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, 4);				/* [2] ptr to struct s1 */

	btf__add_ptr(btf1, 5);				/* [3] ptr to struct s2 */

	btf__add_struct(btf1, "s1", 16);		/* [4] struct s1 { */

	btf__add_field(btf1, "f1", 2, 0, 0);		/*      struct s1 *f1; */

	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; */

							/* } */



	VALIDATE_RAW_BTF(

		btf1,

		"[1] INT 'int' size=4 bits_offset=0 nr_bits=32 encoding=SIGNED",

		"[2] PTR '(anon)' type_id=4",

		"[3] PTR '(anon)' type_id=5",

		"[4] STRUCT 's1' size=16 vlen=2\n"

		"\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");



	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; */

							/* } */



	VALIDATE_RAW_BTF(

		btf2,

		"[1] INT 'int' size=4 bits_offset=0 nr_bits=32 encoding=SIGNED",

		"[2] PTR '(anon)' type_id=4",

		"[3] PTR '(anon)' type_id=5",

		"[4] STRUCT 's1' size=16 vlen=2\n"

		"\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] 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");



	err = btf__dedup(btf2, NULL, NULL);

	if (!ASSERT_OK(err, "btf_dedup"))

		goto cleanup;



	VALIDATE_RAW_BTF(

		btf2,

		"[1] INT 'int' size=4 bits_offset=0 nr_bits=32 encoding=SIGNED",

		"[2] PTR '(anon)' type_id=4",

		"[3] PTR '(anon)' type_id=5",

		"[4] STRUCT 's1' size=16 vlen=2\n"

		"\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");



cleanup:

	btf__free(btf2);

	btf__free(btf1);

}



static void test_split_struct_duped() {

	struct btf *btf1, *btf2;

	int 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, 5);				/* [2] ptr to struct s1 */

	btf__add_fwd(btf1, "s2", BTF_FWD_STRUCT);	/* [3] fwd for struct s2 */

	btf__add_ptr(btf1, 3);				/* [4] ptr to fwd struct s2 */

	btf__add_struct(btf1, "s1", 16);		/* [5] struct s1 { */

	btf__add_field(btf1, "f1", 2, 0, 0);		/*      struct s1 *f1; */

	btf__add_field(btf1, "f2", 4, 64, 0);		/*      struct s2 *f2; */

							/* } */



	VALIDATE_RAW_BTF(

		btf1,

		"[1] INT 'int' size=4 bits_offset=0 nr_bits=32 encoding=SIGNED",

		"[2] PTR '(anon)' type_id=5",

		"[3] FWD 's2' fwd_kind=struct",

		"[4] PTR '(anon)' type_id=3",

		"[5] STRUCT 's1' size=16 vlen=2\n"

		"\t'f1' type_id=2 bits_offset=0\n"

		"\t'f2' type_id=4 bits_offset=64");



	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, 11);				/* [9] ptr to 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_struct(btf2, "s2", 40);		/* [11] struct s2 {	*/

	btf__add_field(btf2, "f1", 7, 0, 0);		/*      struct s1 *f1;	*/

	btf__add_field(btf2, "f2", 9, 64, 0);		/*      struct s2 *f2;	*/

	btf__add_field(btf2, "f3", 6, 128, 0);		/*      int f3;		*/

	btf__add_field(btf2, "f4", 10, 192, 0);		/*      struct s1 f4;	*/

							/* } */

	btf__add_ptr(btf2, 8);				/* [12] ptr to fwd struct s2 */

	btf__add_struct(btf2, "s3", 8);			/* [13] struct s3 { */

	btf__add_field(btf2, "f1", 12, 0, 0);		/*      struct s2 *f1; (fwd) */

							/* } */



	VALIDATE_RAW_BTF(

		btf2,

		"[1] INT 'int' size=4 bits_offset=0 nr_bits=32 encoding=SIGNED",

		"[2] PTR '(anon)' type_id=5",

		"[3] FWD 's2' fwd_kind=struct",

		"[4] PTR '(anon)' type_id=3",

		"[5] STRUCT 's1' size=16 vlen=2\n"

		"\t'f1' type_id=2 bits_offset=0\n"

		"\t'f2' type_id=4 bits_offset=64",

		"[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=11",

		"[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",

		"[11] STRUCT 's2' size=40 vlen=4\n"

		"\t'f1' type_id=7 bits_offset=0\n"

		"\t'f2' type_id=9 bits_offset=64\n"

		"\t'f3' type_id=6 bits_offset=128\n"

		"\t'f4' type_id=10 bits_offset=192",

		"[12] PTR '(anon)' type_id=8",

		"[13] STRUCT 's3' size=8 vlen=1\n"

		"\t'f1' type_id=12 bits_offset=0");



	err = btf__dedup(btf2, NULL, NULL);

	if (!ASSERT_OK(err, "btf_dedup"))

		goto cleanup;



	VALIDATE_RAW_BTF(

		btf2,

		"[1] INT 'int' size=4 bits_offset=0 nr_bits=32 encoding=SIGNED",

		"[2] PTR '(anon)' type_id=5",

		"[3] FWD 's2' fwd_kind=struct",

		"[4] PTR '(anon)' type_id=3",

		"[5] STRUCT 's1' size=16 vlen=2\n"

		"\t'f1' type_id=2 bits_offset=0\n"

		"\t'f2' type_id=4 bits_offset=64",

		"[6] PTR '(anon)' type_id=8",

		"[7] PTR '(anon)' type_id=9",

		"[8] STRUCT 's1' size=16 vlen=2\n"

		"\t'f1' type_id=6 bits_offset=0\n"

		"\t'f2' type_id=7 bits_offset=64",

		"[9] STRUCT 's2' size=40 vlen=4\n"

		"\t'f1' type_id=6 bits_offset=0\n"

		"\t'f2' type_id=7 bits_offset=64\n"

		"\t'f3' type_id=1 bits_offset=128\n"

		"\t'f4' type_id=8 bits_offset=192",

		"[10] STRUCT 's3' size=8 vlen=1\n"

		"\t'f1' type_id=7 bits_offset=0");



cleanup:

	btf__free(btf2);

	btf__free(btf1);

}



void test_btf_dedup_split()

{

	if (test__start_subtest("split_simple"))

		test_split_simple();

	if (test__start_subtest("split_struct_duped"))

		test_split_struct_duped();

	if (test__start_subtest("split_fwd_resolve"))

		test_split_fwd_resolve();

}