use BenchWrapper;

my $BENCHMARKIT = 1;

...

my $bwo = BenchWrapper -> new( $BENCHMARKIT );

...

sub foo {
    my $t0 = $bwo -> mark;
    ...
    my $t1 = $bwo -> mark;
    ...
}

...

package BenchWrapper;

use Benchmark;

sub new {
    bless { BENCHMARKIT => shift() };
}

sub mark {
    $_[0] -> { BENCHMARKIT }
      and return Benchmark -> new;
}

1;