Christoph Lameter wrote: > On Fri, 31 Mar 2006, Nick Piggin wrote: >>You acknowledge that you have to fix ia64 to match current semantics >>first, right? > > > Right. I believe I have done so by making both smb_mb_* full barriers. All bitop and atomic test_and_set, inc_return, etc etc (ie. everything that modifies the operand and returns something) needs to be a full barrier before and after too. >>Now people seem to be worried about the performance impact that will >>have, so I simply suggest that adding two or three new macros for the >>important cases to give you a 90% solution. > > > We could transition some key locations of core code to use _mode bitops > if there are performance problems. > > >>I think Documentation/atomic_ops.txt isn't bad. smp_mb__* really >>is a smp_mb, which can be optimised sometimes. > > > Ok. Then we are on the same page and the solution I presented may be > acceptable. I have a new rev here that changes the naming a bit but I > think we are okay right? Not sure, to be honest. I think it is probably something which needs input from all the other arch people, and Linus, if you intend to use it to introduce new types of barriers. -- SUSE Labs, Novell Inc. Send instant messages to your online friends http://au.messenger.yahoo.com - To unsubscribe from this list: send the line "unsubscribe linux-ia64" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.htmlReceived on Sat Apr 01 13:57:37 2006
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