Not exactly. attributes says:
locked

Setting this attribute is only meaningful when the subroutine or method is to be called by multiple threads. When set on a method subroutine (i.e., one marked with the method attribute below), Perl ensures that any invocation of it implicitly locks its first argument before execution. When set on a non-method subroutine, Perl ensures that a lock is taken on the subroutine itself before execution. The semantics of the lock are exactly those of one explicitly taken with the lock operator immediately after the subroutine is entered.

And that's basically what happens (i think you misunderstand what locking does). 
#!/usr/bin/perl -w -l --  
@ARGV = qw[ foo bar baz ];
use threads;
$|=1;
sub f :locked {
    my $tid = threads->self()->tid();
    print "A}$tid}$_[0]";
    select undef, undef, undef, rand(2);
    print "B}$tid}$_[0]";
}
threads->create(\&f, $_) for @ARGV;
$_->join() for threads->list() 
__END__

A}1}foo
A}2}bar
A}3}baz
B}3}baz
B}2}bar
B}1}foo


#!/usr/bin/perl -w -l --  
@ARGV = qw[ foo bar baz ];
use threads;
$|=1;
sub f :locked {
    my $tid = threads->self()->tid();
    print "A}$tid}$_[0]";
    select undef, undef, undef, rand(2);
    print "B}$tid}$_[0]";
}
threads->create(\&f, $_) for @ARGV;
$_->join() for threads->list() 
__END__

A}1}foo
A}2}bar
A}3}baz
B}1}foo
B}2}bar
B}3}baz

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MJD says "you can't just make shit up and expect the computer to know what you mean, retardo!"
I run a Win32 PPM repository for perl 5.6.x and 5.8.x -- I take requests (README).
** The third rule of perl club is a statement of fact: pod is sexy.

In reply to Re: (ithreads) :locked subs by PodMaster
in thread (ithreads) :locked subs by Anonymous Monk

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