You seem to be spreading functionality that can be contained within the logging function. Why not:
use warning;
use strict;

{
    my %log_seen;

    sub log_info {
        # do not continue if done before
        return if $log_seen{(caller(1))[3]}++;

        warn(@_, "\n");
    }
}

sub f {
    log_info('some information');
    print "called f()\n";
}

f();
f();

__END__
some information
called f()
called f()

[download]

In reply to Re: Why do I get a "used only once" warning here? by repellent
in thread Why do I get a "used only once" warning here? by rovf

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