On Thu, 2014-07-03 at 08:35 -0700, Linus Torvalds wrote: > On Thu, Jul 3, 2014 at 8:31 AM, Linus Torvalds > <[email protected]> wrote: > > > > I don't think we'll support 2 _billion_ processes/threads waiting on > > the same semaphore any time soon, so the 'long' seems a bit of an > > overkill on 64-bit architectures. > > Oh, never mind. The 'struct semaphore' uses it as just a plain count, > but the rwsem ends up splitting up the bits for readers/writers, so we > actually do want the full 64-bit value there.
Yeah, that was the key to reducing the struct size as the rwsem count can't share a 64 bit chunk with the spinlock, unlike some of the other lock. Thanks, Jason -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
