On Tue, 2011-10-18 at 10:26 -0700, Michal Nazarewicz wrote: > > You can do this in a more general fashion by checking the > > zone boundaries and resolving the pfn->page every MAX_ORDER_NR_PAGES. > > That will not be SPARSEMEM specific. > > I've tried doing stuff that way but it ended up with much more code. I guess instead of: >> +static inline bool zone_pfn_same_memmap(unsigned long pfn1, unsigned long pfn2) >> +{ >> + return pfn_to_section_nr(pfn1) == pfn_to_section_nr(pfn2); >> +} You could do: static inline bool zone_pfn_same_maxorder(unsigned long pfn1, unsigned long pfn2) { unsigned long mask = MAX_ORDER_NR_PAGES-1; return (pfn1 & mask) == (pfn2 & mask); } I think that works. Should be the same code you have now, basically. -- Dave -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>