f44696648dbe8b6 parent ba9ddf49391645e6bb93219131a40446538a5e76 author Lee Schermerhorn 1224386803 -0700 committer Linus Torvalds 1224517826 -0700 SHM_LOCKED pages are unevictable Shmem segments locked into memory via shmctl(SHM_LOCKED) should not be kept on the normal LRU, since scanning them is a waste of time and might throw off kswapd's balancing algorithms. Place them on the unevictable LRU list instead. Use the AS_UNEVICTABLE flag to mark address_space of SHM_LOCKed shared memory regions as unevictable. Then these pages will be culled off the normal LRU lists during vmscan. Add new wrapper function to clear the mapping's unevictable state when/if shared memory segment is munlocked. Add 'scan_mapping_unevictable_page()' to mm/vmscan.c to scan all pages in the shmem segment's mapping [struct address_space] for evictability now that they're no longer locked. If so, move them to the appropriate zone lru list. Changes depend on [CONFIG_]UNEVICTABLE_LRU. [kosaki.motohiro@jp.fujitsu.com: revert shm change] Signed-off-by: Lee Schermerhorn Signed-off-by: Rik van Riel Signed-off-by: Kosaki Motohiro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds