On Wed, 2011-06-08 at 22:52 +0200, Ingo Molnar wrote: > Hm, i thought it would be possible to only express it via the > slowpath: if mutex_trylock() succeeds then *all* execution goes into > the slowpath so we don't have to take all the fastpaths into account. Right, but you first have to take wait_lock, then do the trylock, but that's complicated for asm/mutex-null.h because trylock will then also try to obtain the wait_lock. You can do it by creating ___mutex_trylock_slowpath() which contains the meat of __mutex_trylock_slowpath() and then implement atomic_mutex_trylock{_irq,_irqsave,} using that, not releasing wait_lock on success. Shouldn't be too bad, but it ain't too pretty either. Furthermore, like I said in my initial patch, I share Thomas' worry about 'creative' usage of these primitives. -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html