On Mon, 26 Sep 2005, Jp Calderone wrote: > On Sun, 25 Sep 2005 23:30:21 -0400, Victor Ng <[EMAIL PROTECTED]> wrote: >> You could do it with a metaclass, but I think that's probably overkill. >> >> It's not really efficient as it's doing test/set of an RLock all the >> time, but hey - you didn't ask for efficient. :) > > There's a race condition in this version of synchronized which can allow two > or more threads to execute the synchronized function simultaneously.
You could define a meta-lock, and use that to protect the lock-installation action. To avoid bottlenecking on the single meta-lock, you could put a meta-lock in each class, and use that to protect installation of locks in instances of that class. You would, of course, then need a meta-meta-lock to protect those. Also, and more helpfully, you can get a modest speedup by taking out the explicit test for the presence of the lock, and just rely on getting an AttributeError from self._sync_lock.acquire() if it's not there; you could then install the lock in the except suite. tom -- 90% mental, 25% effort, 8% mathematics -- http://mail.python.org/mailman/listinfo/python-list
