Commit 8b1cb1c9 authored by Andrii Nakryiko's avatar Andrii Nakryiko Committed by Daniel Borkmann
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selftest/bpf: Add relocatable bitfield reading tests 



Add a bunch of selftests verifying correctness of relocatable bitfield reading
support in libbpf. Both bpf_probe_read()-based and direct read-based bitfield
macros are tested. core_reloc.c "test_harness" is extended to support raw
tracepoint and new typed raw tracepoints as test BPF program types.

Signed-off-by: default avatarAndrii Nakryiko <andriin@fb.com>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191101222810.1246166-5-andriin@fb.com
parent 94f060e9

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

+82 −2
Original line number Diff line number Diff line
@@ -189,6 +189,42 @@ 
	.fails = true,							\

}



#define BITFIELDS_CASE_COMMON(objfile, test_name_prefix,  name)		\

	.case_name = test_name_prefix#name,				\

	.bpf_obj_file = objfile,					\

	.btf_src_file = "btf__core_reloc_" #name ".o"



#define BITFIELDS_CASE(name, ...) {					\

	BITFIELDS_CASE_COMMON("test_core_reloc_bitfields_probed.o",	\

			      "direct:", name),				\

	.input = STRUCT_TO_CHAR_PTR(core_reloc_##name) __VA_ARGS__,	\

	.input_len = sizeof(struct core_reloc_##name),			\

	.output = STRUCT_TO_CHAR_PTR(core_reloc_bitfields_output)	\

		__VA_ARGS__,						\

	.output_len = sizeof(struct core_reloc_bitfields_output),	\

}, {									\

	BITFIELDS_CASE_COMMON("test_core_reloc_bitfields_direct.o",	\

			      "probed:", name),				\

	.input = STRUCT_TO_CHAR_PTR(core_reloc_##name) __VA_ARGS__,	\

	.input_len = sizeof(struct core_reloc_##name),			\

	.output = STRUCT_TO_CHAR_PTR(core_reloc_bitfields_output)	\

		__VA_ARGS__,						\

	.output_len = sizeof(struct core_reloc_bitfields_output),	\

	.direct_raw_tp = true,						\

}





#define BITFIELDS_ERR_CASE(name) {					\

	BITFIELDS_CASE_COMMON("test_core_reloc_bitfields_probed.o",	\

			      "probed:", name),				\

	.fails = true,							\

}, {									\

	BITFIELDS_CASE_COMMON("test_core_reloc_bitfields_direct.o",	\

			      "direct:", name),				\

	.direct_raw_tp = true,						\

	.fails = true,							\

}



struct core_reloc_test_case {

	const char *case_name;

	const char *bpf_obj_file;
@@ -199,6 +235,7 @@ struct core_reloc_test_case { 
	int output_len;

	bool fails;

	bool relaxed_core_relocs;

	bool direct_raw_tp;

};



static struct core_reloc_test_case test_cases[] = {
@@ -352,6 +389,40 @@ static struct core_reloc_test_case test_cases[] = { 
	EXISTENCE_ERR_CASE(existence__err_arr_kind),

	EXISTENCE_ERR_CASE(existence__err_arr_value_type),

	EXISTENCE_ERR_CASE(existence__err_struct_type),



	/* bitfield relocation checks */

	BITFIELDS_CASE(bitfields, {

		.ub1 = 1,

		.ub2 = 2,

		.ub7 = 96,

		.sb4 = -7,

		.sb20 = -0x76543,

		.u32 = 0x80000000,

		.s32 = -0x76543210,

	}),

	BITFIELDS_CASE(bitfields___bit_sz_change, {

		.ub1 = 6,

		.ub2 = 0xABCDE,

		.ub7 = 1,

		.sb4 = -1,

		.sb20 = -0x17654321,

		.u32 = 0xBEEF,

		.s32 = -0x3FEDCBA987654321,

	}),

	BITFIELDS_CASE(bitfields___bitfield_vs_int, {

		.ub1 = 0xFEDCBA9876543210,

		.ub2 = 0xA6,

		.ub7 = -0x7EDCBA987654321,

		.sb4 = -0x6123456789ABCDE,

		.sb20 = 0xD00D,

		.u32 = -0x76543,

		.s32 = 0x0ADEADBEEFBADB0B,

	}),

	BITFIELDS_CASE(bitfields___just_big_enough, {

		.ub1 = 0xF,

		.ub2 = 0x0812345678FEDCBA,

	}),

	BITFIELDS_ERR_CASE(bitfields___err_too_big_bitfield),

};



struct data {
@@ -361,9 +432,9 @@ struct data { 


void test_core_reloc(void)

{

	const char *probe_name = "raw_tracepoint/sys_enter";

	struct bpf_object_load_attr load_attr = {};

	struct core_reloc_test_case *test_case;

	const char *tp_name, *probe_name;

	int err, duration = 0, i, equal;

	struct bpf_link *link = NULL;

	struct bpf_map *data_map;
@@ -387,6 +458,15 @@ void test_core_reloc(void) 
			  test_case->bpf_obj_file, PTR_ERR(obj)))

			continue;



		/* for typed raw tracepoints, NULL should be specified */

		if (test_case->direct_raw_tp) {

			probe_name = "tp_btf/sys_enter";

			tp_name = NULL;

		} else {

			probe_name = "raw_tracepoint/sys_enter";

			tp_name = "sys_enter";

		}



		prog = bpf_object__find_program_by_title(obj, probe_name);

		if (CHECK(!prog, "find_probe",

			  "prog '%s' not found\n", probe_name))
@@ -407,7 +487,7 @@ void test_core_reloc(void) 
				goto cleanup;

		}



		link = bpf_program__attach_raw_tracepoint(prog, "sys_enter");

		link = bpf_program__attach_raw_tracepoint(prog, tp_name);

		if (CHECK(IS_ERR(link), "attach_raw_tp", "err %ld\n",

			  PTR_ERR(link)))

			goto cleanup;

tools/testing/selftests/bpf/progs/btf__core_reloc_bitfields.c

0 → 100644
+3 −0
Original line number Diff line number Diff line 
#include "core_reloc_types.h"



void f(struct core_reloc_bitfields x) {}

tools/testing/selftests/bpf/progs/btf__core_reloc_bitfields___bit_sz_change.c

0 → 100644
+3 −0
Original line number Diff line number Diff line 
#include "core_reloc_types.h"



void f(struct core_reloc_bitfields___bit_sz_change x) {}

tools/testing/selftests/bpf/progs/btf__core_reloc_bitfields___bitfield_vs_int.c

0 → 100644
+3 −0
Original line number Diff line number Diff line 
#include "core_reloc_types.h"



void f(struct core_reloc_bitfields___bitfield_vs_int x) {}

tools/testing/selftests/bpf/progs/btf__core_reloc_bitfields___err_too_big_bitfield.c

0 → 100644
+3 −0
Original line number Diff line number Diff line 
#include "core_reloc_types.h"



void f(struct core_reloc_bitfields___err_too_big_bitfield x) {}

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