[PATCH bpf-next v5 0/3] libbpf: use func name when pinning programs with LIBBPF_STRICT_SEC_NAME

@@ -285,7 +285,7 @@ struct bpf_program {
 	size_t sub_insn_off;
 
 	char *name;
-	/* sec_name with / replaced by _; makes recursive pinning
+	/* name with / replaced by _; makes recursive pinning
 	 * in bpf_object__pin_programs easier
 	 */
 	char *pin_name;

@@ -614,7 +614,16 @@ static char *__bpf_program__pin_name(struct bpf_program *prog)
 {
 	char *name, *p;
 
-	name = p = strdup(prog->sec_name);
+	if (libbpf_mode & LIBBPF_STRICT_SEC_NAME)
+		name = strdup(prog->name);
+	else
+		name = strdup(prog->sec_name);
+
+	if (!name)
+		return NULL;
+
+	p = name;
+
 	while ((p = strchr(p, '/')))
 		*p = '_';
 

@@ -52,6 +52,9 @@ enum libbpf_strict_mode {
 	 * allowed, with LIBBPF_STRICT_SEC_PREFIX this will become
 	 * unrecognized by libbpf and would have to be just SEC("xdp") and
 	 * SEC("xdp") and SEC("perf_event").
+	 *
+	 * Note, in this mode the program pin path will be based on the
+	 * function name instead of section name.
 	 */
 	LIBBPF_STRICT_SEC_NAME = 0x04,
 

@@ -409,6 +409,10 @@ int main(int argc, char **argv)
 	block_mount = false;
 	bin_name = argv[0];
 
+	ret = libbpf_set_strict_mode(LIBBPF_STRICT_ALL);
+	if (ret)
+		p_err("failed to enable libbpf strict mode: %d", ret);
+
 	hash_init(prog_table.table);
 	hash_init(map_table.table);
 	hash_init(link_table.table);

@@ -1396,8 +1396,6 @@ static int load_with_options(int argc, char **argv, bool first_prog_only)
 
 	while (argc) {
 		if (is_prefix(*argv, "type")) {
-			char *type;
-
 			NEXT_ARG();
 
 			if (common_prog_type != BPF_PROG_TYPE_UNSPEC) {

@@ -1407,21 +1405,26 @@ static int load_with_options(int argc, char **argv, bool first_prog_only)
 			if (!REQ_ARGS(1))
 				goto err_free_reuse_maps;
 
-			/* Put a '/' at the end of type to appease libbpf */
-			type = malloc(strlen(*argv) + 2);
-			if (!type) {
-				p_err("mem alloc failed");
-				goto err_free_reuse_maps;
-			}
-			*type = 0;
-			strcat(type, *argv);
-			strcat(type, "/");
+			err = libbpf_prog_type_by_name(*argv, &common_prog_type,
+						       &expected_attach_type);
+			if (err < 0) {
+				/* Put a '/' at the end of type to appease libbpf */
+				char *type = malloc(strlen(*argv) + 2);
 
-			err = get_prog_type_by_name(type, &common_prog_type,
-						    &expected_attach_type);
-			free(type);
-			if (err < 0)
-				goto err_free_reuse_maps;
+				if (!type) {
+					p_err("mem alloc failed");
+					goto err_free_reuse_maps;
+				}
+				*type = 0;
+				strcat(type, *argv);
+				strcat(type, "/");
+
+				err = get_prog_type_by_name(type, &common_prog_type,
+							    &expected_attach_type);
+				free(type);
+				if (err < 0)
+					goto err_free_reuse_maps;
+			}
 
 			NEXT_ARG();
 		} else if (is_prefix(*argv, "map")) {

@@ -17,7 +17,7 @@
 const char *cfg_pin_path = "/sys/fs/bpf/flow_dissector";
 const char *cfg_map_name = "jmp_table";
 bool cfg_attach = true;
-char *cfg_section_name;
+char *cfg_prog_name;
 char *cfg_path_name;
 
 static void load_and_attach_program(void)

@@ -25,7 +25,11 @@ static void load_and_attach_program(void)
 	int prog_fd, ret;
 	struct bpf_object *obj;
 
-	ret = bpf_flow_load(&obj, cfg_path_name, cfg_section_name,
+	ret = libbpf_set_strict_mode(LIBBPF_STRICT_ALL);
+	if (ret)
+		error(1, 0, "failed to enable libbpf strict mode: %d", ret);
+
+	ret = bpf_flow_load(&obj, cfg_path_name, cfg_prog_name,
 			    cfg_map_name, NULL, &prog_fd, NULL);
 	if (ret)
 		error(1, 0, "bpf_flow_load %s", cfg_path_name);

@@ -75,15 +79,15 @@ static void parse_opts(int argc, char **argv)
 			break;
 		case 'p':
 			if (cfg_path_name)
-				error(1, 0, "only one prog name can be given");
+				error(1, 0, "only one path can be given");
 
 			cfg_path_name = optarg;
 			break;
 		case 's':
-			if (cfg_section_name)
-				error(1, 0, "only one section can be given");
+			if (cfg_prog_name)
+				error(1, 0, "only one prog can be given");
 
-			cfg_section_name = optarg;
+			cfg_prog_name = optarg;
 			break;
 		}
 	}

@@ -94,7 +98,7 @@ static void parse_opts(int argc, char **argv)
 	if (cfg_attach && !cfg_path_name)
 		error(1, 0, "must provide a path to the BPF program");
 
-	if (cfg_attach && !cfg_section_name)
+	if (cfg_attach && !cfg_prog_name)
 		error(1, 0, "must provide a section name");
 }
 

@@ -7,7 +7,7 @@
 
 static inline int bpf_flow_load(struct bpf_object **obj,
 				const char *path,
-				const char *section_name,
+				const char *prog_name,
 				const char *map_name,
 				const char *keys_map_name,
 				int *prog_fd,

@@ -23,13 +23,7 @@ static inline int bpf_flow_load(struct bpf_object **obj,
 	if (ret)
 		return ret;
 
-	main_prog = NULL;
-	bpf_object__for_each_program(prog, *obj) {
-		if (strcmp(section_name, bpf_program__section_name(prog)) == 0) {
-			main_prog = prog;
-			break;
-		}
-	}
+	main_prog = bpf_object__find_program_by_name(*obj, prog_name);
 	if (!main_prog)
 		return -1;
 

@@ -26,22 +26,22 @@ if [[ -z $(ip netns identify $$) ]]; then
 			type flow_dissector
 
 		if ! unshare --net $bpftool prog attach pinned \
-			/sys/fs/bpf/flow/flow_dissector flow_dissector; then
+			/sys/fs/bpf/flow/_dissect flow_dissector; then
 			echo "Unexpected unsuccessful attach in namespace" >&2
 			err=1
 		fi
 
-		$bpftool prog attach pinned /sys/fs/bpf/flow/flow_dissector \
+		$bpftool prog attach pinned /sys/fs/bpf/flow/_dissect \
 			flow_dissector
 
 		if unshare --net $bpftool prog attach pinned \
-			/sys/fs/bpf/flow/flow_dissector flow_dissector; then
+			/sys/fs/bpf/flow/_dissect flow_dissector; then
 			echo "Unexpected successful attach in namespace" >&2
 			err=1
 		fi
 
 		if ! $bpftool prog detach pinned \
-			/sys/fs/bpf/flow/flow_dissector flow_dissector; then
+			/sys/fs/bpf/flow/_dissect flow_dissector; then
 			echo "Failed to detach flow dissector" >&2
 			err=1
 		fi

@@ -95,7 +95,7 @@ else
 fi
 
 # Attach BPF program
-./flow_dissector_load -p bpf_flow.o -s flow_dissector
+./flow_dissector_load -p bpf_flow.o -s _dissect
 
 # Setup
 tc qdisc add dev lo ingress