[PATCH] mm: pfault optimisation

This atomic operation is superfluous: the pte will be added with the
referenced bit set, and the page will be referenced through this mapping after
the page fault handler returns anyway.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: 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 d7ca7de10f4d7db82d32d92de1c2f2c1a548c2fb..7197f9bcd384d99bdd51d858cb8438a67a4198a0 100644 (file)
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1977,7 +1977,6 @@ static int do_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma,
                        goto release;
                inc_mm_counter(mm, anon_rss);
                lru_cache_add_active(page);
-               SetPageReferenced(page);
                page_add_new_anon_rmap(page, vma, address);
        } else {
                /* Map the ZERO_PAGE - vm_page_prot is readonly */