[PATCH] rmap: don't test rss

Remove the three get_mm_counter(mm, rss) tests from rmap.c: there was a
time when testing rss was important to avoid a particular race between
dup_mmap and the anonmm rmap; but now it's just a rather silly pseudo-
optimization, made even more obscure by the get_mm_counter macro.

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/rmap.c b/mm/rmap.c
index facb8cd..28c6cf9 100644 (file)
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -289,8 +289,6 @@ static int page_referenced_one(struct page *page,
        pte_t *pte;
        int referenced = 0;
 
-       if (!get_mm_counter(mm, rss))
-               goto out;
        address = vma_address(page, vma);
        if (address == -EFAULT)
                goto out;
@@ -517,8 +515,6 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma)
        pte_t pteval;
        int ret = SWAP_AGAIN;
 
-       if (!get_mm_counter(mm, rss))
-               goto out;
        address = vma_address(page, vma);
        if (address == -EFAULT)
                goto out;
@@ -766,8 +762,7 @@ static int try_to_unmap_file(struct page *page)
                        if (vma->vm_flags & (VM_LOCKED|VM_RESERVED))
                                continue;
                        cursor = (unsigned long) vma->vm_private_data;
-                       while (get_mm_counter(vma->vm_mm, rss) &&
-                               cursor < max_nl_cursor &&
+                       while ( cursor < max_nl_cursor &&
                                cursor < vma->vm_end - vma->vm_start) {
                                try_to_unmap_cluster(cursor, &mapcount, vma);
                                cursor += CLUSTER_SIZE;