mm, highmem: remove page_address_pool list

We can find free page_address_map instance without the page_address_pool.
So remove it.

Signed-off-by: Joonsoo Kim <js1304@gmail.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Minchan Kim <minchan@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/highmem.c b/mm/highmem.c
index 63083a2803ffd04e59d5e647740f8f9cff196da3..f7455695562b63df426a006348d5879a31c8ee21 100644 (file)
--- a/mm/highmem.c
+++ b/mm/highmem.c
@@ -324,11 +324,7 @@ struct page_address_map {
        void *virtual;
        struct list_head list;
 };
-
-/*
- * page_address_map freelist, allocated from page_address_maps.
- */
-static struct list_head page_address_pool;     /* freelist */
+static struct page_address_map page_address_maps[LAST_PKMAP];
 
 /*
  * Hash table bucket
@@ -393,12 +389,7 @@ void set_page_address(struct page *page, void *virtual)
 
        pas = page_slot(page);
        if (virtual) {          /* Add */
-               BUG_ON(list_empty(&page_address_pool));
-
-               pam = list_entry(page_address_pool.next,
-                               struct page_address_map, list);
-               list_del(&pam->list);
-
+               pam = &page_address_maps[PKMAP_NR((unsigned long)virtual)];
                pam->page = page;
                pam->virtual = virtual;
 
@@ -411,7 +402,6 @@ void set_page_address(struct page *page, void *virtual)
                        if (pam->page == page) {
                                list_del(&pam->list);
                                spin_unlock_irqrestore(&pas->lock, flags);
-                               list_add_tail(&pam->list, &page_address_pool);
                                goto done;
                        }
                }
@@ -421,15 +411,10 @@ done:
        return;
 }
 
-static struct page_address_map page_address_maps[LAST_PKMAP];
-
 void __init page_address_init(void)
 {
        int i;
 
-       INIT_LIST_HEAD(&page_address_pool);
-       for (i = 0; i < ARRAY_SIZE(page_address_maps); i++)
-               list_add(&page_address_maps[i].list, &page_address_pool);
        for (i = 0; i < ARRAY_SIZE(page_address_htable); i++) {
                INIT_LIST_HEAD(&page_address_htable[i].lh);
                spin_lock_init(&page_address_htable[i].lock);