Rik van Riel wrote: > Either of these two would work. Another alternative could be to > let test_and_clear_pte_flags have an exception table entry, where > we jump right to the next instruction if the instruction clearing > the flag fails. > > That is the essentially variant you need for Xen, except the fast > path is still exactly the same it is as when running on native > hardware. >
Hm, that wouldn't end up clearing the bit. You'd need a Xen-specific exception handler to do that, which would turn the whole thing into Xen-specific code, and you're back at adding a pv-op. J - 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/