+ mm-highmem-remove-page_address_pool-list.patch added to -mm tree

+ mm-highmem-remove-page_address_pool-list.patch added to -mm tree

[akpm]

The patch titled
     Subject: mm, highmem: remove page_address_pool list
has been added to the -mm tree.  Its filename is
     mm-highmem-remove-page_address_pool-list.patch

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------------------------------------------------------
From: Joonsoo Kim <js1304@gmail.com>
Subject: 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>
---

 mm/highmem.c |   19 ++-----------------
 1 file changed, 2 insertions(+), 17 deletions(-)

diff -puN mm/highmem.c~mm-highmem-remove-page_address_pool-list mm/highmem.c
--- a/mm/highmem.c~mm-highmem-remove-page_address_pool-list
+++ a/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,
 
 	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,
 			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];