mm: provide more accurate estimation of pages occupied by memmap

If SPARSEMEM is enabled, it won't build page structures for non-existing
pages (holes) within a zone, so provide a more accurate estimation of
pages occupied by memmap if there are bigger holes within the zone.

And pages for highmem zones' memmap will be allocated from lowmem, so
charge nr_kernel_pages for that.

[[email protected]: mark calc_memmap_size __paging_init]
Signed-off-by: Jiang Liu <[email protected]>
Cc: Wen Congyang <[email protected]>
Cc: David Rientjes <[email protected]>
Cc: Maciej Rutecki <[email protected]>
Cc: Chris Clayton <[email protected]>
Cc: "Rafael J . Wysocki" <[email protected]>
Cc: Mel Gorman <[email protected]>
Cc: Minchan Kim <[email protected]>
Cc: KAMEZAWA Hiroyuki <[email protected]>
Cc: Michal Hocko <[email protected]>
Tested-by: Jianguo Wu <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: Johannes Weiner <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

0 files changed, 0 insertions, 0 deletions