Merge branch 'Stop using bpf_object__find_program_by_title API'

Kui-Feng Lee says:

====================

bpf_object__find_program_by_title is going to be deprecated since
v0.7.  Replace all use cases with bpf_object__find_program_by_name if
possible, or use bpf_object__for_each_program to iterate over
programs, matching section names.

V3 fixes a broken test case, fexit_bpf2bpf, in selftests/bpf, using
bpf_obj__for_each_program API instead.

[v2] https://lore.kernel.org/bpf/20211211003608.2764928-1-kuifeng@fb.com/
[v1] https://lore.kernel.org/bpf/20211210190855.1369060-1-kuifeng@fb.com/T/
====================

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>

samples/bpf/hbm.c

@@ -120,6 +120,9 @@ static void do_error(char *msg, bool errno_flag)
 
 static int prog_load(char *prog)
 {
+	struct bpf_program *pos;
+	const char *sec_name;
+
 	obj = bpf_object__open_file(prog, NULL);
 	if (libbpf_get_error(obj)) {
 		printf("ERROR: opening BPF object file failed\n");
@@ -132,7 +135,13 @@ static int prog_load(char *prog)
 		goto err;
 	}
 
-	bpf_prog = bpf_object__find_program_by_title(obj, "cgroup_skb/egress");
+	bpf_object__for_each_program(pos, obj) {
+		sec_name = bpf_program__section_name(pos);
+		if (sec_name && !strcmp(sec_name, "cgroup_skb/egress")) {
+			bpf_prog = pos;
+			break;
+		}
+	}
 	if (!bpf_prog) {
 		printf("ERROR: finding a prog in obj file failed\n");
 		goto err;

samples/bpf/xdp_fwd_user.c

@@ -79,7 +79,9 @@ int main(int argc, char **argv)
 		.prog_type	= BPF_PROG_TYPE_XDP,
 	};
 	const char *prog_name = "xdp_fwd";
-	struct bpf_program *prog;
+	struct bpf_program *prog = NULL;
+	struct bpf_program *pos;
+	const char *sec_name;
 	int prog_fd, map_fd = -1;
 	char filename[PATH_MAX];
 	struct bpf_object *obj;
@@ -134,7 +136,13 @@ int main(int argc, char **argv)
 			return 1;
 		}
 
-		prog = bpf_object__find_program_by_title(obj, prog_name);
+		bpf_object__for_each_program(pos, obj) {
+			sec_name = bpf_program__section_name(pos);
+			if (sec_name && !strcmp(sec_name, prog_name)) {
+				prog = pos;
+				break;
+			}
+		}
 		prog_fd = bpf_program__fd(prog);
 		if (prog_fd < 0) {
 			printf("program not found: %s\n", strerror(prog_fd));

tools/lib/bpf/libbpf.h

@@ -227,6 +227,7 @@ struct btf;
 LIBBPF_API struct btf *bpf_object__btf(const struct bpf_object *obj);
 LIBBPF_API int bpf_object__btf_fd(const struct bpf_object *obj);
 
+LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_object__find_program_by_name() instead")
 LIBBPF_API struct bpf_program *
 bpf_object__find_program_by_title(const struct bpf_object *obj,
 				  const char *title);

tools/perf/builtin-trace.c

@@ -3257,10 +3257,21 @@ static void trace__set_bpf_map_syscalls(struct trace *trace)
 
 static struct bpf_program *trace__find_bpf_program_by_title(struct trace *trace, const char *name)
 {
+	struct bpf_program *pos, *prog = NULL;
+	const char *sec_name;
+
 	if (trace->bpf_obj == NULL)
 		return NULL;
 
-	return bpf_object__find_program_by_title(trace->bpf_obj, name);
+	bpf_object__for_each_program(pos, trace->bpf_obj) {
+		sec_name = bpf_program__section_name(pos);
+		if (sec_name && !strcmp(sec_name, name)) {
+			prog = pos;
+			break;
+		}
+	}
+
+	return prog;
 }
 
 static struct bpf_program *trace__find_syscall_bpf_prog(struct trace *trace, struct syscall *sc,

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

@@ -65,8 +65,8 @@ void serial_test_bpf_obj_id(void)
 		if (CHECK_FAIL(err))
 			goto done;
 
-		prog = bpf_object__find_program_by_title(objs[i],
-							 "raw_tp/sys_enter");
+		prog = bpf_object__find_program_by_name(objs[i],
+							"test_obj_id");
 		if (CHECK_FAIL(!prog))
 			goto done;
 		links[i] = bpf_program__attach(prog);

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

@@ -67,9 +67,9 @@ static int run_test(int cgroup_fd, int server_fd, int family, int type)
 		goto close_bpf_object;
 	}
 
-	prog = bpf_object__find_program_by_title(obj, v4 ?
-						 "cgroup/connect4" :
-						 "cgroup/connect6");
+	prog = bpf_object__find_program_by_name(obj, v4 ?
+						"connect4" :
+						"connect6");
 	if (CHECK(!prog, "find_prog", "connect prog not found\n")) {
 		err = -EIO;
 		goto close_bpf_object;
@@ -83,9 +83,9 @@ static int run_test(int cgroup_fd, int server_fd, int family, int type)
 		goto close_bpf_object;
 	}
 
-	prog = bpf_object__find_program_by_title(obj, v4 ?
-						 "cgroup/getpeername4" :
-						 "cgroup/getpeername6");
+	prog = bpf_object__find_program_by_name(obj, v4 ?
+						"getpeername4" :
+						"getpeername6");
 	if (CHECK(!prog, "find_prog", "getpeername prog not found\n")) {
 		err = -EIO;
 		goto close_bpf_object;
@@ -99,9 +99,9 @@ static int run_test(int cgroup_fd, int server_fd, int family, int type)
 		goto close_bpf_object;
 	}
 
-	prog = bpf_object__find_program_by_title(obj, v4 ?
-						 "cgroup/getsockname4" :
-						 "cgroup/getsockname6");
+	prog = bpf_object__find_program_by_name(obj, v4 ?
+						"getsockname4" :
+						"getsockname6");
 	if (CHECK(!prog, "find_prog", "getsockname prog not found\n")) {
 		err = -EIO;
 		goto close_bpf_object;

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

@@ -10,7 +10,7 @@ static int duration = 0;
 
 #define STRUCT_TO_CHAR_PTR(struct_name) (const char *)&(struct struct_name)
 
-#define MODULES_CASE(name, sec_name, tp_name) {				\
+#define MODULES_CASE(name, pg_name, tp_name) {				\
 	.case_name = name,						\
 	.bpf_obj_file = "test_core_reloc_module.o",			\
 	.btf_src_file = NULL, /* find in kernel module BTFs */		\
@@ -28,7 +28,7 @@ static int duration = 0;
 		.comm_len = sizeof("test_progs"),			\
 	},								\
 	.output_len = sizeof(struct core_reloc_module_output),		\
-	.prog_sec_name = sec_name,					\
+	.prog_name = pg_name,						\
 	.raw_tp_name = tp_name,						\
 	.trigger = __trigger_module_test_read,				\
 	.needs_testmod = true,						\
@@ -43,7 +43,9 @@ static int duration = 0;
 #define FLAVORS_CASE_COMMON(name)					\
 	.case_name = #name,						\
 	.bpf_obj_file = "test_core_reloc_flavors.o",			\
-	.btf_src_file = "btf__core_reloc_" #name ".o"			\
+	.btf_src_file = "btf__core_reloc_" #name ".o",			\
+	.raw_tp_name = "sys_enter",					\
+	.prog_name = "test_core_flavors"				\
 
 #define FLAVORS_CASE(name) {						\
 	FLAVORS_CASE_COMMON(name),					\
@@ -66,7 +68,9 @@ static int duration = 0;
 #define NESTING_CASE_COMMON(name)					\
 	.case_name = #name,						\
 	.bpf_obj_file = "test_core_reloc_nesting.o",			\
-	.btf_src_file = "btf__core_reloc_" #name ".o"
+	.btf_src_file = "btf__core_reloc_" #name ".o",			\
+	.raw_tp_name = "sys_enter",					\
+	.prog_name = "test_core_nesting"				\
 
 #define NESTING_CASE(name) {						\
 	NESTING_CASE_COMMON(name),					\
@@ -91,7 +95,9 @@ static int duration = 0;
 #define ARRAYS_CASE_COMMON(name)					\
 	.case_name = #name,						\
 	.bpf_obj_file = "test_core_reloc_arrays.o",			\
-	.btf_src_file = "btf__core_reloc_" #name ".o"
+	.btf_src_file = "btf__core_reloc_" #name ".o",			\
+	.raw_tp_name = "sys_enter",					\
+	.prog_name = "test_core_arrays"					\
 
 #define ARRAYS_CASE(name) {						\
 	ARRAYS_CASE_COMMON(name),					\
@@ -123,7 +129,9 @@ static int duration = 0;
 #define PRIMITIVES_CASE_COMMON(name)					\
 	.case_name = #name,						\
 	.bpf_obj_file = "test_core_reloc_primitives.o",			\
-	.btf_src_file = "btf__core_reloc_" #name ".o"
+	.btf_src_file = "btf__core_reloc_" #name ".o",			\
+	.raw_tp_name = "sys_enter",					\
+	.prog_name = "test_core_primitives"				\
 
 #define PRIMITIVES_CASE(name) {						\
 	PRIMITIVES_CASE_COMMON(name),					\
@@ -158,6 +166,8 @@ static int duration = 0;
 		.e = 5, .f = 6, .g = 7, .h = 8,				\
 	},								\
 	.output_len = sizeof(struct core_reloc_mods_output),		\
+	.raw_tp_name = "sys_enter",					\
+	.prog_name = "test_core_mods",					\
 }
 
 #define PTR_AS_ARR_CASE(name) {						\
@@ -174,6 +184,8 @@ static int duration = 0;
 		.a = 3,							\
 	},								\
 	.output_len = sizeof(struct core_reloc_ptr_as_arr),		\
+	.raw_tp_name = "sys_enter",					\
+	.prog_name = "test_core_ptr_as_arr",				\
 }
 
 #define INTS_DATA(struct_name) STRUCT_TO_CHAR_PTR(struct_name) {	\
@@ -190,7 +202,9 @@ static int duration = 0;
 #define INTS_CASE_COMMON(name)						\
 	.case_name = #name,						\
 	.bpf_obj_file = "test_core_reloc_ints.o",			\
-	.btf_src_file = "btf__core_reloc_" #name ".o"
+	.btf_src_file = "btf__core_reloc_" #name ".o",			\
+	.raw_tp_name = "sys_enter",					\
+	.prog_name = "test_core_ints"
 
 #define INTS_CASE(name) {						\
 	INTS_CASE_COMMON(name),						\
@@ -208,7 +222,9 @@ static int duration = 0;
 #define FIELD_EXISTS_CASE_COMMON(name)					\
 	.case_name = #name,						\
 	.bpf_obj_file = "test_core_reloc_existence.o",			\
-	.btf_src_file = "btf__core_reloc_" #name ".o"			\
+	.btf_src_file = "btf__core_reloc_" #name ".o",			\
+	.raw_tp_name = "sys_enter",					\
+	.prog_name = "test_core_existence"
 
 #define BITFIELDS_CASE_COMMON(objfile, test_name_prefix,  name)		\
 	.case_name = test_name_prefix#name,				\
@@ -223,6 +239,8 @@ static int duration = 0;
 	.output = STRUCT_TO_CHAR_PTR(core_reloc_bitfields_output)	\
 		__VA_ARGS__,						\
 	.output_len = sizeof(struct core_reloc_bitfields_output),	\
+	.raw_tp_name = "sys_enter",					\
+	.prog_name = "test_core_bitfields",				\
 }, {									\
 	BITFIELDS_CASE_COMMON("test_core_reloc_bitfields_direct.o",	\
 			      "direct:", name),				\
@@ -231,25 +249,29 @@ static int duration = 0;
 	.output = STRUCT_TO_CHAR_PTR(core_reloc_bitfields_output)	\
 		__VA_ARGS__,						\
 	.output_len = sizeof(struct core_reloc_bitfields_output),	\
-	.prog_sec_name = "tp_btf/sys_enter",				\
+	.prog_name = "test_core_bitfields_direct",			\
 }
 
 
 #define BITFIELDS_ERR_CASE(name) {					\
 	BITFIELDS_CASE_COMMON("test_core_reloc_bitfields_probed.o",	\
 			      "probed:", name),				\
 	.fails = true,							\
+	.raw_tp_name = "sys_enter",					\
+	.prog_name = "test_core_bitfields",				\
 }, {									\
 	BITFIELDS_CASE_COMMON("test_core_reloc_bitfields_direct.o",	\
 			      "direct:", name),				\
-	.prog_sec_name = "tp_btf/sys_enter",				\
 	.fails = true,							\
+	.prog_name = "test_core_bitfields_direct",			\
 }
 
 #define SIZE_CASE_COMMON(name)						\
 	.case_name = #name,						\
 	.bpf_obj_file = "test_core_reloc_size.o",			\
-	.btf_src_file = "btf__core_reloc_" #name ".o"
+	.btf_src_file = "btf__core_reloc_" #name ".o",			\
+	.raw_tp_name = "sys_enter",					\
+	.prog_name = "test_core_size"
 
 #define SIZE_OUTPUT_DATA(type)						\
 	STRUCT_TO_CHAR_PTR(core_reloc_size_output) {			\
@@ -277,8 +299,10 @@ static int duration = 0;
 
 #define TYPE_BASED_CASE_COMMON(name)					\
 	.case_name = #name,						\
-	.bpf_obj_file = "test_core_reloc_type_based.o",		\
-	.btf_src_file = "btf__core_reloc_" #name ".o"			\
+	.bpf_obj_file = "test_core_reloc_type_based.o",			\
+	.btf_src_file = "btf__core_reloc_" #name ".o",			\
+	.raw_tp_name = "sys_enter",					\
+	.prog_name = "test_core_type_based"
 
 #define TYPE_BASED_CASE(name, ...) {					\
 	TYPE_BASED_CASE_COMMON(name),					\
@@ -295,7 +319,9 @@ static int duration = 0;
 #define TYPE_ID_CASE_COMMON(name)					\
 	.case_name = #name,						\
 	.bpf_obj_file = "test_core_reloc_type_id.o",			\
-	.btf_src_file = "btf__core_reloc_" #name ".o"			\
+	.btf_src_file = "btf__core_reloc_" #name ".o",			\
+	.raw_tp_name = "sys_enter",					\
+	.prog_name = "test_core_type_id"
 
 #define TYPE_ID_CASE(name, setup_fn) {					\
 	TYPE_ID_CASE_COMMON(name),					\
@@ -312,7 +338,9 @@ static int duration = 0;
 #define ENUMVAL_CASE_COMMON(name)					\
 	.case_name = #name,						\
 	.bpf_obj_file = "test_core_reloc_enumval.o",			\
-	.btf_src_file = "btf__core_reloc_" #name ".o"			\
+	.btf_src_file = "btf__core_reloc_" #name ".o",			\
+	.raw_tp_name = "sys_enter",					\
+	.prog_name = "test_core_enumval"
 
 #define ENUMVAL_CASE(name, ...) {					\
 	ENUMVAL_CASE_COMMON(name),					\
@@ -342,7 +370,7 @@ struct core_reloc_test_case {
 	bool fails;
 	bool needs_testmod;
 	bool relaxed_core_relocs;
-	const char *prog_sec_name;
+	const char *prog_name;
 	const char *raw_tp_name;
 	setup_test_fn setup;
 	trigger_test_fn trigger;
@@ -497,11 +525,13 @@ static struct core_reloc_test_case test_cases[] = {
 			.comm_len = sizeof("test_progs"),
 		},
 		.output_len = sizeof(struct core_reloc_kernel_output),
+		.raw_tp_name = "sys_enter",
+		.prog_name = "test_core_kernel",
 	},
 
 	/* validate we can find kernel module BTF types for relocs/attach */
-	MODULES_CASE("module_probed", "raw_tp/bpf_testmod_test_read", "bpf_testmod_test_read"),
-	MODULES_CASE("module_direct", "tp_btf/bpf_testmod_test_read", NULL),
+	MODULES_CASE("module_probed", "test_core_module_probed", "bpf_testmod_test_read"),
+	MODULES_CASE("module_direct", "test_core_module_direct", NULL),
 
 	/* validate BPF program can use multiple flavors to match against
 	 * single target BTF type
@@ -580,6 +610,8 @@ static struct core_reloc_test_case test_cases[] = {
 			.c = 0, /* BUG in clang, should be 3 */
 		},
 		.output_len = sizeof(struct core_reloc_misc_output),
+		.raw_tp_name = "sys_enter",
+		.prog_name = "test_core_misc",
 	},
 
 	/* validate field existence checks */
@@ -848,14 +880,9 @@ void test_core_reloc(void)
 		if (!ASSERT_OK_PTR(obj, "obj_open"))
 			goto cleanup;
 
-		probe_name = "raw_tracepoint/sys_enter";
-		tp_name = "sys_enter";
-		if (test_case->prog_sec_name) {
-			probe_name = test_case->prog_sec_name;
-			tp_name = test_case->raw_tp_name; /* NULL for tp_btf */
-		}
-
-		prog = bpf_object__find_program_by_title(obj, probe_name);
+		probe_name = test_case->prog_name;
+		tp_name = test_case->raw_tp_name; /* NULL for tp_btf */
+		prog = bpf_object__find_program_by_name(obj, probe_name);
 		if (CHECK(!prog, "find_probe",
 			  "prog '%s' not found\n", probe_name))
 			goto cleanup;