tracing: Use trace_seq instead of open code string appending

	return 0;

}

static int append_filter_string(struct event_filter *filter,

				char *string)

{

	int newlen;

	char *new_filter_string;

	if (WARN_ON(!filter->filter_string))

		return -EINVAL;

	newlen = strlen(filter->filter_string) + strlen(string) + 1;

	new_filter_string = kmalloc(newlen, GFP_KERNEL);

	if (!new_filter_string)

		return -ENOMEM;

	strcpy(new_filter_string, filter->filter_string);

	strcat(new_filter_string, string);

	kfree(filter->filter_string);

	filter->filter_string = new_filter_string;

	return 0;

}

static void append_filter_err(struct filter_parse_state *ps,

			      struct event_filter *filter)

{

	struct trace_seq *s;

	int pos = ps->lasterr_pos;

	char *buf, *pbuf;

	char *buf;

	int len;

	buf = (char *)__get_free_page(GFP_KERNEL);

	if (!buf)

	if (WARN_ON(!filter->filter_string))

		return;

	append_filter_string(filter, "\n");

	memset(buf, ' ', PAGE_SIZE);

	if (pos > PAGE_SIZE - 128)

		pos = 0;

	buf[pos] = '^';

	pbuf = &buf[pos] + 1;

	sprintf(pbuf, "\nparse_error: %s\n", err_text[ps->lasterr]);

	append_filter_string(filter, buf);

	free_page((unsigned long) buf);

	s = kmalloc(sizeof(*s), GFP_KERNEL);

	if (!s)

		return;

	trace_seq_init(s);

	len = strlen(filter->filter_string);

	if (pos > len)

		len = pos;

	trace_seq_puts(s, filter->filter_string);

	trace_seq_printf(s, "\n%*s", pos, "^");

	trace_seq_printf(s, "\nparse_error: %s\n", err_text[ps->lasterr]);

	trace_seq_putc(s, 0);

	buf = kmemdup_nul(s->buffer, s->seq.len, GFP_KERNEL);

	if (buf) {

		kfree(filter->filter_string);

		filter->filter_string = buf;

	}

	kfree(s);

}

static inline struct event_filter *event_filter(struct trace_event_file *file)