Skip to content
Commit 288468c3 authored by Andrea Arcangeli's avatar Andrea Arcangeli Committed by Linus Torvalds
Browse files

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: default avatarAndrea Arcangeli <aarcange@redhat.com>
Signed-off-by: default avatarRik van Riel <riel@redhat.com>
[kamezawa.hiroyu@jp.fujitsu.com: fix false positive BUG_ON in __page_set_anon_rmap]
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent ba6f0ff3
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment