Subj : Re: recursive mutexes
To   : comp.programming.threads
From : Uenal Mutlu
Date : Mon May 16 2005 01:13 pm

"doug" wrote
>
> For the current code I'm working on, it would take me several hours, perhaps
> days, to type in the lock information his tool requires.

If you strictly follow the deadlock theorem I posted here, then you can
be assured that no deadlock will happen.

> That's not to mention the fact that threads are created dynamically, and their behaviour
> is unpredictable (I see nothing in his tool that allows you to grab this
> lock OR that lock, depending on some state.).

It is intended for locks put on individual shared objects. Ie. it is not
for "locking threads" or something that.
It is irrelevant when the threads are created. It is important what the
threadproc does: ie. in which order it locks the objects.
The requirement is: you must create a list of all your shared objects (the order
is irrelevant), then in each threadproc pick the objects you want to use
just in the same order as they are on the list.

> All he's done is specialise hierarchical locking for simplified scenarios.

Not true. The deadlock theorem I formulated is an important generalization.

.