[PATCH] mm: zap_pte_range dont dirty anon
zap_pte_range already avoids wasting time to mark_page_accessed on anon pages:
it can also skip anon set_page_dirty - the page only needs to be marked dirty
if shared with another mm, but that will say pte_dirty too.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/mm/memory.c b/mm/memory.c
index 222c13e..fd5d4c6 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -574,12 +574,14 @@
addr) != page->index)
set_pte_at(tlb->mm, addr, pte,
pgoff_to_pte(page->index));
- if (pte_dirty(ptent))
- set_page_dirty(page);
if (PageAnon(page))
dec_mm_counter(tlb->mm, anon_rss);
- else if (pte_young(ptent))
- mark_page_accessed(page);
+ else {
+ if (pte_dirty(ptent))
+ set_page_dirty(page);
+ if (pte_young(ptent))
+ mark_page_accessed(page);
+ }
tlb->freed++;
page_remove_rmap(page);
tlb_remove_page(tlb, page);