+> 	> 	> /*
+> 	> 	>  * Allow read-after-read or read-after-write recursion of the
+> 	> 	>  * same lock class for RT rwlocks.
+> 	> 	>  */
+> 	> 	> if (read == 3 && (prev->read == 3 || prev->read == 0))

Pff, shoulda left it reader vs reader.. but it's gotta be wrong anyway.