On 2016/2/15 10:42, Joonsoo Kim wrote: >> >> I have a question about the zone continuity. because hole exists at >> arbitrary position in a page block. Therefore, only pageblock_pf_to_page() >> is insufficiency, whether pageblock aligned pfn or not , the pfn_valid_within() >> is necessary. >> >> eh: 120M-122M is a range of page block, but the 120.5M-121.5M is holes, only by >> pageblock_pfn_to_page() to conclude in the result is inaccurate > > contiguous may be misleading word. It doesn't represent there are no > hole. It only represents that all pageblocks within zone span belong to > corresponding zone and validity of all pageblock aligned pfn is > checked. So, if it is set, we can safely call pfn_to_page() for pageblock > aligned pfn in that zone without checking pfn_valid(). > > Thanks. > Hi Joonsoo, So "contiguous" here only means that struct page is exist, and don't care whether the memory is exist, right? Thanks, Xishi Qiu > > . > -- 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/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>