From: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> Date: Tue, 24 Aug 2010 08:01:25 +1000 > On Mon, 2010-08-23 at 15:44 +0200, Arnd Bergmann wrote: >> >> * Alpha has an optimization for the uniprocessor case, where the atomic >> instructions get turned into nonatomic additions. The spinlock based >> version uses no locks on UP but disables interrupts for reasons I don't >> understand (nothing running at interrupt time should try to access an rwsem). >> Should the generic version do the same as Alpha? > > I've seen drivers in the past do trylocks at interrupt time ... tho I > agree it sucks. Recently there was a thread where this was declared absolutely illegal. Maybe it was allowed, or sort-of worked before, and that's why it's accounted for with IRQ disables in some implementations. I don't know. -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
