1 // SPDX-License-Identifier: GPL-2.0
3  * trace_events_synth - synthetic trace events
27 	C(BAD_NAME,		"Illegal name"),		\
28 	C(INVALID_CMD,		"Command must be of the form: <name> field[;field] ..."),\
29 	C(INVALID_DYN_CMD,	"Command must be of the form: s or -:[synthetic/]<name> field[;field] ..."),\
30 	C(EVENT_EXISTS,		"Event already exists"),	\
84 static bool synth_event_match(const char *system, const char *event,
97 	return ev->ops == &synth_event_ops;  in is_synth_event()
107 	struct synth_event *event = to_synth_event(ev);  in synth_event_is_busy()  local
109 	return event->ref != 0;  in synth_event_is_busy()
112 static bool synth_event_match(const char *system, const char *event,  in synth_event_match()  argument
117 	return strcmp(sev->name, event) == 0 &&  in synth_event_match()
130 	struct synth_event *event = call->data;  in synth_event_define_fields()  local
132 	char *name, *type;  in synth_event_define_fields()  local
136 	for (i = 0, n_u64 = 0; i < event->n_fields; i++) {  in synth_event_define_fields()
137 		size = event->fields[i]->size;  in synth_event_define_fields()
138 		is_signed = event->fields[i]->is_signed;  in synth_event_define_fields()
139 		type = event->fields[i]->type;  in synth_event_define_fields()
140 		name = event->fields[i]->name;  in synth_event_define_fields()
141 		ret = trace_define_field(call, type, name, offset, size,  in synth_event_define_fields()
146 		event->fields[i]->offset = n_u64;  in synth_event_define_fields()
148 		if (event->fields[i]->is_string && !event->fields[i]->is_dynamic) {  in synth_event_define_fields()
157 	event->n_u64 = n_u64;  in synth_event_define_fields()
196 		return -EINVAL;  in synth_field_string_size()
197 	start += sizeof("char[") - 1;  in synth_field_string_size()
201 		return -EINVAL;  in synth_field_string_size()
203 	len = end - start;  in synth_field_string_size()
205 		return -EINVAL;  in synth_field_string_size()
208 		return 0; /* variable-length string */  in synth_field_string_size()
218 		return -EINVAL;  in synth_field_string_size()
316 				      char *print_fmt, char *name,  in print_synth_event_num_val()  argument
321 		trace_seq_printf(s, print_fmt, name, val->as_u8, space);  in print_synth_event_num_val()
325 		trace_seq_printf(s, print_fmt, name, val->as_u16, space);  in print_synth_event_num_val()
329 		trace_seq_printf(s, print_fmt, name, val->as_u32, space);  in print_synth_event_num_val()
333 		trace_seq_printf(s, print_fmt, name, val->as_u64, space);  in print_synth_event_num_val()
340 					   struct trace_event *event)  in print_synth_event()  argument
342 	struct trace_array *tr = iter->tr;  in print_synth_event()
343 	struct trace_seq *s = &iter->seq;  in print_synth_event()
350 	entry = (struct synth_trace_event *)iter->ent;  in print_synth_event()
351 	se = container_of(event, struct synth_event, call.event);  in print_synth_event()
353 	trace_seq_printf(s, "%s: ", se->name);  in print_synth_event()
355 	for (i = 0, n_u64 = 0; i < se->n_fields; i++) {  in print_synth_event()
359 		fmt = synth_field_fmt(se->fields[i]->type);  in print_synth_event()
362 		if (tr && tr->trace_flags & TRACE_ITER_VERBOSE)  in print_synth_event()
368 		if (se->fields[i]->is_string) {  in print_synth_event()
369 			if (se->fields[i]->is_dynamic) {  in print_synth_event()
370 				union trace_synth_field *data = &entry->fields[n_u64];  in print_synth_event()
372 				trace_seq_printf(s, print_fmt, se->fields[i]->name,  in print_synth_event()
374 						 (char *)entry + data->as_dynamic.offset,  in print_synth_event()
375 						 i == se->n_fields - 1 ? "" : " ");  in print_synth_event()
378 				trace_seq_printf(s, print_fmt, se->fields[i]->name,  in print_synth_event()
380 						 (char *)&entry->fields[n_u64].as_u64,  in print_synth_event()
381 						 i == se->n_fields - 1 ? "" : " ");  in print_synth_event()
384 		} else if (se->fields[i]->is_stack) {  in print_synth_event()
385 			union trace_synth_field *data = &entry->fields[n_u64];  in print_synth_event()
386 			unsigned long *p = (void *)entry + data->as_dynamic.offset;  in print_synth_event()
388 			trace_seq_printf(s, "%s=STACK:\n", se->fields[i]->name);  in print_synth_event()
389 			for (j = 1; j < data->as_dynamic.len / sizeof(long); j++)  in print_synth_event()
394 			    __def_gfpflag_names, {-1, NULL} };  in print_synth_event()
395 			char *space = (i == se->n_fields - 1 ? "" : " ");  in print_synth_event()
398 						  se->fields[i]->name,  in print_synth_event()
399 						  se->fields[i]->size,  in print_synth_event()
400 						  &entry->fields[n_u64],  in print_synth_event()
403 			if (strcmp(se->fields[i]->type, "gfp_t") == 0) {  in print_synth_event()
406 						      entry->fields[n_u64].as_u64,  in print_synth_event()
424 				 struct synth_event *event,  in trace_string()  argument
435 		union trace_synth_field *data = &entry->fields[*n_u64];  in trace_string()
438 		data->as_dynamic.offset = struct_size(entry, fields, event->n_u64) + data_size;  in trace_string()
439 		data->as_dynamic.len = len;  in trace_string()
441 		ret = fetch_store_string((unsigned long)str_val, &entry->fields[*n_u64], entry);  in trace_string()
445 		str_field = (char *)&entry->fields[*n_u64].as_u64;  in trace_string()
464 				 struct synth_event *event,  in trace_stack()  argument
469 	union trace_synth_field *data = &entry->fields[*n_u64];  in trace_stack()
474 	data_offset = struct_size(entry, fields, event->n_u64);  in trace_stack()
490 	data->as_dynamic.offset = data_offset;  in trace_stack()
491 	data->as_dynamic.len = len;  in trace_stack()
507 	struct synth_event *event;  in trace_event_raw_event_synth()  local
510 	event = trace_file->event_call->data;  in trace_event_raw_event_synth()
515 	fields_size = event->n_u64 * sizeof(u64);  in trace_event_raw_event_synth()
517 	for (i = 0; i < event->n_dynamic_fields; i++) {  in trace_event_raw_event_synth()
518 		unsigned int field_pos = event->dynamic_fields[i]->field_pos;  in trace_event_raw_event_synth()
524 		if (event->dynamic_fields[i]->is_stack) {  in trace_event_raw_event_synth()
536 	 * Avoid ring buffer recursion detection, as this event  in trace_event_raw_event_synth()
537 	 * is being performed within another event.  in trace_event_raw_event_synth()
539 	buffer = trace_file->tr->array_buffer.buffer;  in trace_event_raw_event_synth()
547 	for (i = 0, n_u64 = 0; i < event->n_fields; i++) {  in trace_event_raw_event_synth()
549 		if (event->fields[i]->is_string) {  in trace_event_raw_event_synth()
552 			len = trace_string(entry, event, str_val,  in trace_event_raw_event_synth()
553 					   event->fields[i]->is_dynamic,  in trace_event_raw_event_synth()
556 		} else if (event->fields[i]->is_stack) {  in trace_event_raw_event_synth()
559 			len = trace_stack(entry, event, stack,  in trace_event_raw_event_synth()
563 			struct synth_field *field = event->fields[i];  in trace_event_raw_event_synth()
566 			switch (field->size) {  in trace_event_raw_event_synth()
568 				entry->fields[n_u64].as_u8 = (u8)val;  in trace_event_raw_event_synth()
572 				entry->fields[n_u64].as_u16 = (u16)val;  in trace_event_raw_event_synth()
576 				entry->fields[n_u64].as_u32 = (u32)val;  in trace_event_raw_event_synth()
580 				entry->fields[n_u64].as_u64 = val;  in trace_event_raw_event_synth()
595 		kfree(call->print_fmt);  in free_synth_event_print_fmt()
596 		call->print_fmt = NULL;  in free_synth_event_print_fmt()
600 static int __set_synth_event_print_fmt(struct synth_event *event,  in __set_synth_event_print_fmt()  argument
608 #define LEN_OR_ZERO (len ? len - pos : 0)  in __set_synth_event_print_fmt()
611 	for (i = 0; i < event->n_fields; i++) {  in __set_synth_event_print_fmt()
612 		fmt = synth_field_fmt(event->fields[i]->type);  in __set_synth_event_print_fmt()
614 				event->fields[i]->name, fmt,  in __set_synth_event_print_fmt()
615 				i == event->n_fields - 1 ? "" : ", ");  in __set_synth_event_print_fmt()
619 	for (i = 0; i < event->n_fields; i++) {  in __set_synth_event_print_fmt()
620 		if (event->fields[i]->is_string &&  in __set_synth_event_print_fmt()
621 		    event->fields[i]->is_dynamic)  in __set_synth_event_print_fmt()
623 				", __get_str(%s)", event->fields[i]->name);  in __set_synth_event_print_fmt()
624 		else if (event->fields[i]->is_stack)  in __set_synth_event_print_fmt()
626 				", __get_stacktrace(%s)", event->fields[i]->name);  in __set_synth_event_print_fmt()
629 					", REC->%s", event->fields[i]->name);  in __set_synth_event_print_fmt()
640 	struct synth_event *event = call->data;  in set_synth_event_print_fmt()  local
645 	len = __set_synth_event_print_fmt(event, NULL, 0);  in set_synth_event_print_fmt()
649 		return -ENOMEM;  in set_synth_event_print_fmt()
652 	__set_synth_event_print_fmt(event, print_fmt, len + 1);  in set_synth_event_print_fmt()
653 	call->print_fmt = print_fmt;  in set_synth_event_print_fmt()
660 	kfree(field->type);  in free_synth_field()
661 	kfree(field->name);  in free_synth_field()
669 	 * For backward compatibility, the old synthetic event command  in check_field_version()
687 	int len, ret = -ENOMEM;  in parse_synth_field()
694 			return ERR_PTR(-EINVAL);  in parse_synth_field()
707 		return ERR_PTR(-EINVAL);  in parse_synth_field()
714 		return ERR_PTR(-ENOMEM);  in parse_synth_field()
719 		len -= strlen(array);  in parse_synth_field()
721 	field->name = kmemdup_nul(field_name, len, GFP_KERNEL);  in parse_synth_field()
722 	if (!field->name)  in parse_synth_field()
725 	if (!is_good_name(field->name)) {  in parse_synth_field()
727 		ret = -EINVAL;  in parse_synth_field()
739 	field->type = kzalloc(len, GFP_KERNEL);  in parse_synth_field()
740 	if (!field->type)  in parse_synth_field()
743 	seq_buf_init(&s, field->type, len);  in parse_synth_field()
754 	size = synth_field_size(field->type);  in parse_synth_field()
760 		ret = -EINVAL;  in parse_synth_field()
763 		if (synth_field_is_string(field->type) ||  in parse_synth_field()
764 		    synth_field_is_stack(field->type)) {  in parse_synth_field()
767 			len = sizeof("__data_loc ") + strlen(field->type) + 1;  in parse_synth_field()
774 			seq_buf_puts(&s, field->type);  in parse_synth_field()
780 			kfree(field->type);  in parse_synth_field()
781 			field->type = type;  in parse_synth_field()
783 			field->is_dynamic = true;  in parse_synth_field()
787 			ret = -EINVAL;  in parse_synth_field()
791 	field->size = size;  in parse_synth_field()
793 	if (synth_field_is_string(field->type))  in parse_synth_field()
794 		field->is_string = true;  in parse_synth_field()
795 	else if (synth_field_is_stack(field->type))  in parse_synth_field()
796 		field->is_stack = true;  in parse_synth_field()
798 	field->is_signed = synth_field_signed(field->type);  in parse_synth_field()
812 	kfree(tp->name);  in free_synth_tracepoint()
816 static struct tracepoint *alloc_synth_tracepoint(char *name)  in alloc_synth_tracepoint()  argument
822 		return ERR_PTR(-ENOMEM);  in alloc_synth_tracepoint()
824 	tp->name = kstrdup(name, GFP_KERNEL);  in alloc_synth_tracepoint()
825 	if (!tp->name) {  in alloc_synth_tracepoint()
827 		return ERR_PTR(-ENOMEM);  in alloc_synth_tracepoint()
833 struct synth_event *find_synth_event(const char *name)  in find_synth_event()  argument
836 	struct synth_event *event;  in find_synth_event()  local
841 		event = to_synth_event(pos);  in find_synth_event()
842 		if (strcmp(event->name, name) == 0)  in find_synth_event()
843 			return event;  in find_synth_event()
855 static int register_synth_event(struct synth_event *event)  in register_synth_event()  argument
857 	struct trace_event_call *call = &event->call;  in register_synth_event()
860 	event->call.class = &event->class;  in register_synth_event()
861 	event->class.system = kstrdup(SYNTH_SYSTEM, GFP_KERNEL);  in register_synth_event()
862 	if (!event->class.system) {  in register_synth_event()
863 		ret = -ENOMEM;  in register_synth_event()
867 	event->tp = alloc_synth_tracepoint(event->name);  in register_synth_event()
868 	if (IS_ERR(event->tp)) {  in register_synth_event()
869 		ret = PTR_ERR(event->tp);  in register_synth_event()
870 		event->tp = NULL;  in register_synth_event()
874 	INIT_LIST_HEAD(&call->class->fields);  in register_synth_event()
875 	call->event.funcs = &synth_event_funcs;  in register_synth_event()
876 	call->class->fields_array = synth_event_fields_array;  in register_synth_event()
878 	ret = register_trace_event(&call->event);  in register_synth_event()
880 		ret = -ENODEV;  in register_synth_event()
883 	call->flags = TRACE_EVENT_FL_TRACEPOINT;  in register_synth_event()
884 	call->class->reg = trace_event_reg;  in register_synth_event()
885 	call->class->probe = trace_event_raw_event_synth;  in register_synth_event()
886 	call->data = event;  in register_synth_event()
887 	call->tp = event->tp;  in register_synth_event()
891 		pr_warn("Failed to register synthetic event: %s\n",  in register_synth_event()
903 	unregister_trace_event(&call->event);  in register_synth_event()
907 static int unregister_synth_event(struct synth_event *event)  in unregister_synth_event()  argument
909 	struct trace_event_call *call = &event->call;  in unregister_synth_event()
917 static void free_synth_event(struct synth_event *event)  in free_synth_event()  argument
921 	if (!event)  in free_synth_event()
924 	for (i = 0; i < event->n_fields; i++)  in free_synth_event()
925 		free_synth_field(event->fields[i]);  in free_synth_event()
927 	kfree(event->fields);  in free_synth_event()
928 	kfree(event->dynamic_fields);  in free_synth_event()
929 	kfree(event->name);  in free_synth_event()
930 	kfree(event->class.system);  in free_synth_event()
931 	free_synth_tracepoint(event->tp);  in free_synth_event()
932 	free_synth_event_print_fmt(&event->call);  in free_synth_event()
933 	kfree(event);  in free_synth_event()
936 static struct synth_event *alloc_synth_event(const char *name, int n_fields,  in alloc_synth_event()  argument
940 	struct synth_event *event;  in alloc_synth_event()  local
942 	event = kzalloc(sizeof(*event), GFP_KERNEL);  in alloc_synth_event()
943 	if (!event) {  in alloc_synth_event()
944 		event = ERR_PTR(-ENOMEM);  in alloc_synth_event()
948 	event->name = kstrdup(name, GFP_KERNEL);  in alloc_synth_event()
949 	if (!event->name) {  in alloc_synth_event()
950 		kfree(event);  in alloc_synth_event()
951 		event = ERR_PTR(-ENOMEM);  in alloc_synth_event()
955 	event->fields = kcalloc(n_fields, sizeof(*event->fields), GFP_KERNEL);  in alloc_synth_event()
956 	if (!event->fields) {  in alloc_synth_event()
957 		free_synth_event(event);  in alloc_synth_event()
958 		event = ERR_PTR(-ENOMEM);  in alloc_synth_event()
963 		if (fields[i]->is_dynamic)  in alloc_synth_event()
967 		event->dynamic_fields = kcalloc(n_dynamic_fields,  in alloc_synth_event()
968 						sizeof(*event->dynamic_fields),  in alloc_synth_event()
970 		if (!event->dynamic_fields) {  in alloc_synth_event()
971 			free_synth_event(event);  in alloc_synth_event()
972 			event = ERR_PTR(-ENOMEM);  in alloc_synth_event()
977 	dyn_event_init(&event->devent, &synth_event_ops);  in alloc_synth_event()
980 		fields[i]->field_pos = i;  in alloc_synth_event()
981 		event->fields[i] = fields[i];  in alloc_synth_event()
983 		if (fields[i]->is_dynamic)  in alloc_synth_event()
984 			event->dynamic_fields[j++] = fields[i];  in alloc_synth_event()
986 	event->n_dynamic_fields = j;  in alloc_synth_event()
987 	event->n_fields = n_fields;  in alloc_synth_event()
989 	return event;  in alloc_synth_event()
997 	size = synth_field_size((char *)arg_pair->lhs);  in synth_event_check_arg_fn()
999 		if (strstr((char *)arg_pair->lhs, "["))  in synth_event_check_arg_fn()
1003 	return size ? 0 : -EINVAL;  in synth_event_check_arg_fn()
1007  * synth_event_add_field - Add a new field to a synthetic event cmd
1008  * @cmd: A pointer to the dynevent_cmd struct representing the new event
1010  * @name: The name of the new field to add
1012  * Add a new field to a synthetic event cmd object.  Field ordering is in
1021 			  const char *name)  in synth_event_add_field()  argument
1026 	if (cmd->type != DYNEVENT_TYPE_SYNTH)  in synth_event_add_field()
1027 		return -EINVAL;  in synth_event_add_field()
1029 	if (!type || !name)  in synth_event_add_field()
1030 		return -EINVAL;  in synth_event_add_field()
1035 	arg_pair.rhs = name;  in synth_event_add_field()
1041 	if (++cmd->n_fields > SYNTH_FIELDS_MAX)  in synth_event_add_field()
1042 		ret = -EINVAL;  in synth_event_add_field()
1049  * synth_event_add_field_str - Add a new field to a synthetic event cmd
1050  * @cmd: A pointer to the dynevent_cmd struct representing the new event
1051  * @type_name: The type and name of the new field to add, as a single string
1053  * Add a new field to a synthetic event cmd object, as a single
1055  * name', which will be appended by ';'.  No sanity checking is done -
1056  * what's passed in is assumed to already be well-formed.  Field
1069 	if (cmd->type != DYNEVENT_TYPE_SYNTH)  in synth_event_add_field_str()
1070 		return -EINVAL;  in synth_event_add_field_str()
1073 		return -EINVAL;  in synth_event_add_field_str()
1083 	if (++cmd->n_fields > SYNTH_FIELDS_MAX)  in synth_event_add_field_str()
1084 		ret = -EINVAL;  in synth_event_add_field_str()
1091  * synth_event_add_fields - Add multiple fields to a synthetic event cmd
1092  * @cmd: A pointer to the dynevent_cmd struct representing the new event
1093  * @fields: An array of type/name field descriptions
1096  * Add a new set of fields to a synthetic event cmd object.  The event
1097  * fields that will be defined for the event should be passed in as an
1115 		if (fields[i].type == NULL || fields[i].name == NULL) {  in synth_event_add_fields()
1116 			ret = -EINVAL;  in synth_event_add_fields()
1120 		ret = synth_event_add_field(cmd, fields[i].type, fields[i].name);  in synth_event_add_fields()
1130  * __synth_event_gen_cmd_start - Start a synthetic event command from arg list
1131  * @cmd: A pointer to the dynevent_cmd struct representing the new event
1132  * @name: The name of the synthetic event
1133  * @mod: The module creating the event, NULL if not created from a module
1142  * Generate a synthetic event command to be executed by
1150  * of a type followed by a field name.
1157 int __synth_event_gen_cmd_start(struct dynevent_cmd *cmd, const char *name,  in __synth_event_gen_cmd_start()  argument
1164 	cmd->event_name = name;  in __synth_event_gen_cmd_start()
1165 	cmd->private_data = mod;  in __synth_event_gen_cmd_start()
1167 	if (cmd->type != DYNEVENT_TYPE_SYNTH)  in __synth_event_gen_cmd_start()
1168 		return -EINVAL;  in __synth_event_gen_cmd_start()
1171 	arg.str = name;  in __synth_event_gen_cmd_start()
1178 		const char *type, *name;  in __synth_event_gen_cmd_start()  local
1183 		name = va_arg(args, const char *);  in __synth_event_gen_cmd_start()
1184 		if (!name)  in __synth_event_gen_cmd_start()
1187 		if (++cmd->n_fields > SYNTH_FIELDS_MAX) {  in __synth_event_gen_cmd_start()
1188 			ret = -EINVAL;  in __synth_event_gen_cmd_start()
1192 		ret = synth_event_add_field(cmd, type, name);  in __synth_event_gen_cmd_start()
1203  * synth_event_gen_cmd_array_start - Start synthetic event command from an array
1204  * @cmd: A pointer to the dynevent_cmd struct representing the new event
1205  * @name: The name of the synthetic event
1206  * @mod: The module creating the event, NULL if not created from a module
1207  * @fields: An array of type/name field descriptions
1210  * Generate a synthetic event command to be executed by
1217  * The event fields that will be defined for the event should be
1227 int synth_event_gen_cmd_array_start(struct dynevent_cmd *cmd, const char *name,  in synth_event_gen_cmd_array_start()  argument
1236 	cmd->event_name = name;  in synth_event_gen_cmd_array_start()
1237 	cmd->private_data = mod;  in synth_event_gen_cmd_array_start()
1239 	if (cmd->type != DYNEVENT_TYPE_SYNTH)  in synth_event_gen_cmd_array_start()
1240 		return -EINVAL;  in synth_event_gen_cmd_array_start()
1243 		return -EINVAL;  in synth_event_gen_cmd_array_start()
1246 	arg.str = name;  in synth_event_gen_cmd_array_start()
1252 		if (fields[i].type == NULL || fields[i].name == NULL)  in synth_event_gen_cmd_array_start()
1253 			return -EINVAL;  in synth_event_gen_cmd_array_start()
1255 		ret = synth_event_add_field(cmd, fields[i].type, fields[i].name);  in synth_event_gen_cmd_array_start()
1264 static int __create_synth_event(const char *name, const char *raw_fields)  in __create_synth_event()  argument
1270 	struct synth_event *event = NULL;  in __create_synth_event()  local
1274 	 *  - Add synthetic event: <event_name> field[;field] ...  in __create_synth_event()
1275 	 *  - Remove synthetic event: !<event_name> field[;field] ...  in __create_synth_event()
1279 	if (name[0] == '\0') {  in __create_synth_event()
1281 		return -EINVAL;  in __create_synth_event()
1284 	if (!is_good_name(name)) {  in __create_synth_event()
1285 		synth_err(SYNTH_ERR_BAD_NAME, errpos(name));  in __create_synth_event()
1286 		return -EINVAL;  in __create_synth_event()
1291 	event = find_synth_event(name);  in __create_synth_event()
1292 	if (event) {  in __create_synth_event()
1293 		synth_err(SYNTH_ERR_EVENT_EXISTS, errpos(name));  in __create_synth_event()
1294 		ret = -EEXIST;  in __create_synth_event()
1300 		ret = -ENOMEM;  in __create_synth_event()
1307 			ret = -ENOMEM;  in __create_synth_event()
1321 			field = parse_synth_field(argc - consumed,  in __create_synth_event()
1348 				ret = -EINVAL;  in __create_synth_event()
1354 				ret = -EINVAL;  in __create_synth_event()
1365 			ret = -EINVAL;  in __create_synth_event()
1373 		ret = -EINVAL;  in __create_synth_event()
1377 	event = alloc_synth_event(name, n_fields, fields);  in __create_synth_event()
1378 	if (IS_ERR(event)) {  in __create_synth_event()
1379 		ret = PTR_ERR(event);  in __create_synth_event()
1380 		event = NULL;  in __create_synth_event()
1383 	ret = register_synth_event(event);  in __create_synth_event()
1385 		dyn_event_add(&event->devent, &event->call);  in __create_synth_event()
1387 		free_synth_event(event);  in __create_synth_event()
1404  * synth_event_create - Create a new synthetic event
1405  * @name: The name of the new synthetic event
1406  * @fields: An array of type/name field descriptions
1408  * @mod: The module creating the event, NULL if not created from a module
1410  * Create a new synthetic event with the given name under the
1411  * trace/events/synthetic/ directory.  The event fields that will be
1412  * defined for the event should be passed in as an array of struct
1417  * If the new synthetic event is being created from a module, the mod
1418  * param must be non-NULL.  This will ensure that the trace buffer
1421  * The new synth event should be deleted using synth_event_delete()
1422  * function.  The new synthetic event can be generated from modules or
1427 int synth_event_create(const char *name, struct synth_field_desc *fields,  in synth_event_create()  argument
1436 		return -ENOMEM;  in synth_event_create()
1440 	ret = synth_event_gen_cmd_array_start(&cmd, name, mod,  in synth_event_create()
1457 	if (se->ref)  in destroy_synth_event()
1458 		return -EBUSY;  in destroy_synth_event()
1460 	if (trace_event_dyn_busy(&se->call))  in destroy_synth_event()
1461 		return -EBUSY;  in destroy_synth_event()
1465 		dyn_event_remove(&se->devent);  in destroy_synth_event()
1473  * synth_event_delete - Delete a synthetic event
1474  * @event_name: The name of the new synthetic event
1476  * Delete a synthetic event that was created with synth_event_create().
1484 	int ret = -ENOENT;  in synth_event_delete()
1489 		mod = se->mod;  in synth_event_delete()
1519 		return -ENOMEM;  in check_command()
1523 		ret = -EINVAL;  in check_command()
1532 		ret = -ENOMEM;  in check_command()
1538 		ret = -EINVAL;  in check_command()
1547 	char *name = NULL, *fields, *p;  in create_or_delete_synth_event()  local
1565 		ret = -EINVAL;  in create_or_delete_synth_event()
1569 	name = kmemdup_nul(raw_command, p ? p - raw_command : strlen(raw_command), GFP_KERNEL);  in create_or_delete_synth_event()
1570 	if (!name)  in create_or_delete_synth_event()
1571 		return -ENOMEM;  in create_or_delete_synth_event()
1573 	if (name[0] == '!') {  in create_or_delete_synth_event()
1574 		ret = synth_event_delete(name + 1);  in create_or_delete_synth_event()
1580 	ret = __create_synth_event(name, fields);  in create_or_delete_synth_event()
1582 	kfree(name);  in create_or_delete_synth_event()
1592 	ret = create_or_delete_synth_event(cmd->seq.buffer);  in synth_event_run_command()
1596 	se = find_synth_event(cmd->event_name);  in synth_event_run_command()
1598 		return -ENOENT;  in synth_event_run_command()
1600 	se->mod = cmd->private_data;  in synth_event_run_command()
1606  * synth_event_cmd_init - Initialize a synthetic event command object
1607  * @cmd: A pointer to the dynevent_cmd struct representing the new event
1611  * Initialize a synthetic event command object.  Use this before
1630 	 * Normal event tracing doesn't get called at all unless the  in __synth_event_trace_init()
1638 	if (!(file->flags & EVENT_FILE_FL_ENABLED) ||  in __synth_event_trace_init()
1640 		trace_state->disabled = true;  in __synth_event_trace_init()
1641 		ret = -ENOENT;  in __synth_event_trace_init()
1645 	trace_state->event = file->event_call->data;  in __synth_event_trace_init()
1658 	fields_size = trace_state->event->n_u64 * sizeof(u64);  in __synth_event_trace_start()
1662 	 * Avoid ring buffer recursion detection, as this event  in __synth_event_trace_start()
1663 	 * is being performed within another event.  in __synth_event_trace_start()
1665 	trace_state->buffer = file->tr->array_buffer.buffer;  in __synth_event_trace_start()
1666 	ring_buffer_nest_start(trace_state->buffer);  in __synth_event_trace_start()
1668 	entry_size = sizeof(*trace_state->entry) + fields_size;  in __synth_event_trace_start()
1669 	trace_state->entry = trace_event_buffer_reserve(&trace_state->fbuffer,  in __synth_event_trace_start()
1672 	if (!trace_state->entry) {  in __synth_event_trace_start()
1673 		ring_buffer_nest_end(trace_state->buffer);  in __synth_event_trace_start()
1674 		ret = -EINVAL;  in __synth_event_trace_start()
1683 	trace_event_buffer_commit(&trace_state->fbuffer);  in __synth_event_trace_end()
1685 	ring_buffer_nest_end(trace_state->buffer);  in __synth_event_trace_end()
1689  * synth_event_trace - Trace a synthetic event
1690  * @file: The trace_event_file representing the synthetic event
1692  * @...: Variable number of args containing the event values
1694  * Trace a synthetic event using the values passed in the variable
1698  * of vals must match the number of field in the synthetic event, and
1699  * must be in the same order as the synthetic event fields.
1703  * reserved in the event for the string, using these pointers.
1716 		if (ret == -ENOENT)  in synth_event_trace()
1721 	if (state.event->n_dynamic_fields) {  in synth_event_trace()
1724 		for (i = 0; i < state.event->n_fields; i++) {  in synth_event_trace()
1727 			if (state.event->fields[i]->is_string &&  in synth_event_trace()
1728 			    state.event->fields[i]->is_dynamic) {  in synth_event_trace()
1742 	if (n_vals != state.event->n_fields) {  in synth_event_trace()
1743 		ret = -EINVAL;  in synth_event_trace()
1750 	for (i = 0, n_u64 = 0; i < state.event->n_fields; i++) {  in synth_event_trace()
1755 		if (state.event->fields[i]->is_string) {  in synth_event_trace()
1758 			len = trace_string(state.entry, state.event, str_val,  in synth_event_trace()
1759 					   state.event->fields[i]->is_dynamic,  in synth_event_trace()
1763 			struct synth_field *field = state.event->fields[i];  in synth_event_trace()
1765 			switch (field->size) {  in synth_event_trace()
1767 				state.entry->fields[n_u64].as_u8 = (u8)val;  in synth_event_trace()
1771 				state.entry->fields[n_u64].as_u16 = (u16)val;  in synth_event_trace()
1775 				state.entry->fields[n_u64].as_u32 = (u32)val;  in synth_event_trace()
1779 				state.entry->fields[n_u64].as_u64 = val;  in synth_event_trace()
1794  * synth_event_trace_array - Trace a synthetic event from an array
1795  * @file: The trace_event_file representing the synthetic event
1799  * Trace a synthetic event using the values passed in as 'vals'.
1802  * vals must match the number of field in the synthetic event, and
1803  * must be in the same order as the synthetic event fields.
1807  * reserved in the event for the string, using these pointers.
1821 		if (ret == -ENOENT)  in synth_event_trace_array()
1826 	if (state.event->n_dynamic_fields) {  in synth_event_trace_array()
1827 		for (i = 0; i < state.event->n_dynamic_fields; i++) {  in synth_event_trace_array()
1828 			field_pos = state.event->dynamic_fields[i]->field_pos;  in synth_event_trace_array()
1839 	if (n_vals != state.event->n_fields) {  in synth_event_trace_array()
1840 		ret = -EINVAL;  in synth_event_trace_array()
1846 	for (i = 0, n_u64 = 0; i < state.event->n_fields; i++) {  in synth_event_trace_array()
1847 		if (state.event->fields[i]->is_string) {  in synth_event_trace_array()
1850 			len = trace_string(state.entry, state.event, str_val,  in synth_event_trace_array()
1851 					   state.event->fields[i]->is_dynamic,  in synth_event_trace_array()
1855 			struct synth_field *field = state.event->fields[i];  in synth_event_trace_array()
1858 			switch (field->size) {  in synth_event_trace_array()
1860 				state.entry->fields[n_u64].as_u8 = (u8)val;  in synth_event_trace_array()
1864 				state.entry->fields[n_u64].as_u16 = (u16)val;  in synth_event_trace_array()
1868 				state.entry->fields[n_u64].as_u32 = (u32)val;  in synth_event_trace_array()
1872 				state.entry->fields[n_u64].as_u64 = val;  in synth_event_trace_array()
1886  * synth_event_trace_start - Start piecewise synthetic event trace
1887  * @file: The trace_event_file representing the synthetic event
1890  * Start the trace of a synthetic event field-by-field rather than all
1893  * This function 'opens' an event trace, which means space is reserved
1894  * for the event in the trace buffer, after which the event's
1899  * track of the current event trace state until the event trace is
1900  * closed (and the event finally traced) using
1904  * have been added for each event trace, regardless of whether adding
1907  * Note also that for a given event trace, all fields must be added
1919 		return -EINVAL;  in synth_event_trace_start()
1923 		if (ret == -ENOENT)  in synth_event_trace_start()
1928 	if (trace_state->event->n_dynamic_fields)  in synth_event_trace_start()
1929 		return -ENOTSUPP;  in synth_event_trace_start()
1942 	struct synth_event *event;  in __synth_event_add_val()  local
1946 		ret = -EINVAL;  in __synth_event_add_val()
1952 		if (trace_state->add_next) {  in __synth_event_add_val()
1953 			ret = -EINVAL;  in __synth_event_add_val()
1956 		trace_state->add_name = true;  in __synth_event_add_val()
1958 		if (trace_state->add_name) {  in __synth_event_add_val()
1959 			ret = -EINVAL;  in __synth_event_add_val()
1962 		trace_state->add_next = true;  in __synth_event_add_val()
1965 	if (trace_state->disabled)  in __synth_event_add_val()
1968 	event = trace_state->event;  in __synth_event_add_val()
1969 	if (trace_state->add_name) {  in __synth_event_add_val()
1970 		for (i = 0; i < event->n_fields; i++) {  in __synth_event_add_val()
1971 			field = event->fields[i];  in __synth_event_add_val()
1972 			if (strcmp(field->name, field_name) == 0)  in __synth_event_add_val()
1976 			ret = -EINVAL;  in __synth_event_add_val()
1980 		if (trace_state->cur_field >= event->n_fields) {  in __synth_event_add_val()
1981 			ret = -EINVAL;  in __synth_event_add_val()
1984 		field = event->fields[trace_state->cur_field++];  in __synth_event_add_val()
1987 	entry = trace_state->entry;  in __synth_event_add_val()
1988 	if (field->is_string) {  in __synth_event_add_val()
1992 		if (field->is_dynamic) { /* add_val can't do dynamic strings */  in __synth_event_add_val()
1993 			ret = -EINVAL;  in __synth_event_add_val()
1998 			ret = -EINVAL;  in __synth_event_add_val()
2002 		str_field = (char *)&entry->fields[field->offset];  in __synth_event_add_val()
2005 		switch (field->size) {  in __synth_event_add_val()
2007 			trace_state->entry->fields[field->offset].as_u8 = (u8)val;  in __synth_event_add_val()
2011 			trace_state->entry->fields[field->offset].as_u16 = (u16)val;  in __synth_event_add_val()
2015 			trace_state->entry->fields[field->offset].as_u32 = (u32)val;  in __synth_event_add_val()
2019 			trace_state->entry->fields[field->offset].as_u64 = val;  in __synth_event_add_val()
2028  * synth_event_add_next_val - Add the next field's value to an open synth trace
2032  * Set the value of the next field in an event that's been opened by
2038  * This function assumes all the fields in an event are to be set one
2039  * after another - successive calls to this function are made, one for
2040  * each field, in the order of the fields in the event, until all
2046  * synth_event_add_val() can't be intermixed for a given event trace -
2050  * values have been added for each event trace, regardless of whether
2063  * synth_event_add_val - Add a named field's value to an open synth trace
2064  * @field_name: The name of the synthetic event field value to set
2068  * Set the value of the named field in an event that's been opened by
2074  * This function looks up the field name, and if found, sets the field
2077  * none-piecewise synth_event_trace() instead if efficiency is more
2081  * synth_event_add_val() can't be intermixed for a given event trace -
2085  * values have been added for each event trace, regardless of whether
2098  * synth_event_trace_end - End piecewise synthetic event trace
2101  * End the trace of a synthetic event opened by
2104  * This function 'closes' an event trace, which basically means that
2105  * it commits the reserved event and cleans up other loose ends.
2108  * track of the current event trace state opened with
2112  * added for each event trace, regardless of whether adding all field
2120 		return -EINVAL;  in synth_event_trace_end()
2131 	const char *name;  in create_synth_event()  local
2140 	name = raw_command;  in create_synth_event()
2143 	if (name[0] != 's' || name[1] != ':')  in create_synth_event()
2144 		return -ECANCELED;  in create_synth_event()
2145 	name += 2;  in create_synth_event()
2150 		return -EINVAL;  in create_synth_event()
2155 	/* This interface accepts group name prefix */  in create_synth_event()
2156 	if (strchr(name, '/')) {  in create_synth_event()
2157 		len = str_has_prefix(name, SYNTH_SYSTEM "/");  in create_synth_event()
2160 			return -EINVAL;  in create_synth_event()
2162 		name += len;  in create_synth_event()
2165 	len = name - raw_command;  in create_synth_event()
2173 	name = kmemdup_nul(raw_command + len, p - raw_command - len, GFP_KERNEL);  in create_synth_event()
2174 	if (!name)  in create_synth_event()
2175 		return -ENOMEM;  in create_synth_event()
2177 	ret = __create_synth_event(name, fields);  in create_synth_event()
2179 	kfree(name);  in create_synth_event()
2186 	struct synth_event *event = to_synth_event(ev);  in synth_event_release()  local
2189 	if (event->ref)  in synth_event_release()
2190 		return -EBUSY;  in synth_event_release()
2192 	if (trace_event_dyn_busy(&event->call))  in synth_event_release()
2193 		return -EBUSY;  in synth_event_release()
2195 	ret = unregister_synth_event(event);  in synth_event_release()
2200 	free_synth_event(event);  in synth_event_release()
2204 static int __synth_event_show(struct seq_file *m, struct synth_event *event)  in __synth_event_show()  argument
2210 	seq_printf(m, "%s\t", event->name);  in __synth_event_show()
2212 	for (i = 0; i < event->n_fields; i++) {  in __synth_event_show()
2213 		field = event->fields[i];  in __synth_event_show()
2215 		type = field->type;  in __synth_event_show()
2217 		if (t) { /* __data_loc belongs in format but not event desc */  in __synth_event_show()
2223 		seq_printf(m, "%s %s%s", type, field->name,  in __synth_event_show()
2224 			   i == event->n_fields - 1 ? "" : "; ");  in __synth_event_show()
2234 	struct synth_event *event = to_synth_event(ev);  in synth_event_show()  local
2236 	seq_printf(m, "s:%s/", event->class.system);  in synth_event_show()
2238 	return __synth_event_show(m, event);  in synth_event_show()
2266 	if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) {  in synth_events_open()
2318 		err = -ENODEV;  in trace_events_synth_init()