From 288468c334e98aacbb7e2fb8bde6bc1adcd55e05 Mon Sep 17 00:00:00 2001 From: Andrea Arcangeli Date: Mon, 9 Aug 2010 17:19:09 -0700 Subject: [PATCH] rmap: always use anon_vma root pointer Always use anon_vma->root pointer instead of anon_vma_chain.prev. Also optimize the map-paths, if a mapping is already established no need to overwrite it with root anon-vma list, we can keep the more finegrined anon-vma and skip the overwrite: see the PageAnon check in !exclusive case. This is also the optimization that hidden the ksm bug as this tends to make ksm_might_need_to_copy skip the copy, but only the proper fix to ksm_might_need_to_copy guarantees not triggering the ksm bug unless ksm is in use. this is an optimization only... [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Andrea Arcangeli Signed-off-by: Rik van Riel [kamezawa.hiroyu@jp.fujitsu.com: fix false positive BUG_ON in __page_set_anon_rmap] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Reading git-format-patch failed