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Instead of having one piece of code > (calculate_totalreserve_pages()) describe at a distance the behaviour of > another piece of code (setup_per_zone_lowmem_reserve()), let's describe > an invariant of the data ("lowmem_reserve is monotonic, up to the first > zero value"), at the site where the data is defined. I agree. > > I know sometimes in code this complex we do need these > "spooky-action-at-a-distance" comments but this doesn't seem like one of > those places to me. My concern on this change is that the correctness of calculate_totalreserve_pages() now relies on the implementation of setup_per_zone_lowmem_reserve(). How can we make sure in the future this will not break when setup_per_zone_lowmem_reserve() is changed? Hoping people read the comment and do the right thing? Best Regards, Yan, Zi