On Fri, Dec 08, 2006 at 10:46:17AM -0800, Linus Torvalds wrote: > > > On Fri, 8 Dec 2006, David Howells wrote: > > > > In fact I think more things have LL/SC than have CMPXCHG. > > But you cannot expose ll/sc to C, so that's a bogus argument. Yes you can. Well, you can on ARM at least. Between the load exclusive you can do anything you like until you hit the store exclusive. If you haven't touched the location (with anything other than another load exclusive) and no other CPU has issued a load exclusive, your store exclusive succeeds. Whether you have branches, loads or stores to other locations, etc. None of that matters. Not so bogus as you make out. -- Russell King Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/ maintainer of: - 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/
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