use strict;
use warnings;
use Data::Dumper;

_create_node ("p1","pp1","first");
_create_node ("pp1","ppp1","second");
_create_node ("ppp1","pppp1","third");
_create_node ("pppp1","ppppp1","root");

my $infos = _go_through("p1");

print Dumper $infos;

sub _create_node
  {
    my ($node,$parent,$node_info) = @_;
    no strict 'refs';
    @{$node}{qw/parent info/} = ($parent,$node_info);
  }

sub _go_through
  {
    no strict 'refs';
    my ($node) = @_;
    return "" unless defined ${$node}{"info"};
    my @info_nodes;
    while (${$node}{"info"} ne "root"){
      push @info_nodes, (${$node}{"info"});
      $node = ${$node}{"parent"};
    }
    return \@info_nodes;
  }

##</code><code>##

$VAR1 = [
          'first',
          'second',
          'third'
        ];

##</code><code>##

sub _go_through {
    no strict 'refs';
    my ($node) = @_;
    return unless defined $node->{info};

    my @info_nodes;
    while ( $node->{info} ne 'root' ) {
        push @info_nodes, $node->{info};
        $node = $node->{parent};
    }

    return \@info_nodes;
}

##</code><code>##

Can't use string ("p1") as a HASH ref while "strict refs" in use at ...