Subj : Re: recursive mutexes
To   : comp.programming.threads
From : Uenal Mutlu
Date : Thu May 19 2005 12:24 am

"Casper H.S. Dik" wrote
> "Uenal Mutlu" writes:
....
> (The recursive mutex is only slightly more expensive
> than the ordinary mutex as the unlock path is more
> expensive)

Actually it is just an increment and a comparision of the currentthreadid vs.
the lock holding threadid in Lock(), and a simple decrement in Unlock().
The overhead for recursively locking is far less than the first aquisition
(== non-recursive mutex) of the lock. Cf. code snippet of my other posting to doug and David.

.