Index: linux-2.6.19-rc2-mm1/mm/hugetlb.c
===================================================================
--- linux-2.6.19-rc2-mm1.orig/mm/hugetlb.c	2006-10-18 21:24:03.990964479 -0500
+++ linux-2.6.19-rc2-mm1/mm/hugetlb.c	2006-10-18 21:26:23.144479786 -0500
@@ -30,7 +30,7 @@ static unsigned int free_huge_pages_node
  * Number of pages taken from the pool that we have not processed yet.
  * This is used to avoid falsely reporting OOM conditions.
  */
-static unsigned int tentative_huge_pages; /* = 0 */
+static atomic_t tentative_huge_pages; /* = 0 */
 
 /*
  * Protects updates to hugepage_freelists, nr_huge_pages, free_huge_pages and
@@ -39,20 +39,6 @@ static unsigned int tentative_huge_pages
 static DEFINE_SPINLOCK(hugetlb_lock);
 
 
-static int page_tentative(struct page *page)
-{
-	BUG_ON(!PageCompound(page));
-	BUG_ON(page != (struct page *)page_private(page));
-	return atomic_read(&page[1]._count);
-}
-
-static void set_page_tentative(struct page *page, int value)
-{
-	BUG_ON(!PageCompound(page));
-	BUG_ON(page != (struct page *)page_private(page));
-	atomic_set(&page[1]._count, value);
-}
-
 static void clear_huge_page(struct page *page, unsigned long addr)
 {
 	int i;
@@ -116,14 +102,11 @@ static void free_huge_page(struct page *
 	INIT_LIST_HEAD(&page->lru);
 
 	spin_lock(&hugetlb_lock);
-	switch (page_tentative(page)) {
-	case 2:
-		/* tentative and from the reserved pool */
-		resv_huge_pages++;
-		/* FALLTHROUGH */
-	case 1:
-		/* tentative */
-		tentative_huge_pages--;
+	if (!TestSetPageUptodate(page)) {
+		if (PageReferenced(page))
+			resv_huge_pages++;
+		else
+			atomic_inc(&tentative_huge_pages);
 	}
 	enqueue_huge_page(page);
 	spin_unlock(&hugetlb_lock);
@@ -163,14 +146,14 @@ static struct page *alloc_huge_page(stru
 		 * attempting to instantiate the same page in a shared
 		 * mapping. */
 		if (! resv_huge_pages ) {
-			BUG_ON(! tentative_huge_pages);
+			BUG_ON(! atomic_read(&tentative_huge_pages));
 			spin_unlock(&hugetlb_lock);
 			return ERR_PTR(-EAGAIN);
 		}
 		resv_huge_pages--;
 	} else if (free_huge_pages <= resv_huge_pages) {
 		/* Draw from the non-reserved free pool */
-		if (tentative_huge_pages)
+		if (atomic_read(&tentative_huge_pages))
 			page = ERR_PTR(-EAGAIN);
 		else
 			page = ERR_PTR(-ENOMEM);
@@ -181,21 +164,21 @@ static struct page *alloc_huge_page(stru
 	page = dequeue_huge_page(vma, addr);
 	BUG_ON(! page); /* We've already checked the counts */
 
-	tentative_huge_pages++;
-	set_page_tentative(page, (vma->vm_flags & VM_MAYSHARE) ? 2 : 1);
-	spin_unlock(&hugetlb_lock);
+	ClearPageUptodate(page);
+	atomic_inc(&tentative_huge_pages);
+	if (vma->vm_flags & VM_MAYSHARE)
+		SetPageReferenced(page);
+	else
+		ClearPageReferenced(page);
 	set_page_refcounted(page);
+	spin_unlock(&hugetlb_lock);
 	return page;
 }
 
 static void keep_huge_page(struct page *page)
 {
-	spin_lock(&hugetlb_lock);
-	if (page_tentative(page)) {
-		tentative_huge_pages--;
-		set_page_tentative(page, 0);
-	}
-	spin_unlock(&hugetlb_lock);
+	if (!TestSetPageUptodate(page))
+		atomic_dec(&tentative_huge_pages);
 }
 
 static int __init hugetlb_init(void)
Index: linux-2.6.19-rc2-mm1/include/linux/page-flags.h
===================================================================
--- linux-2.6.19-rc2-mm1.orig/include/linux/page-flags.h	2006-10-18 21:24:04.004637525 -0500
+++ linux-2.6.19-rc2-mm1/include/linux/page-flags.h	2006-10-18 21:25:06.078311240 -0500
@@ -139,6 +139,7 @@ static inline void SetPageUptodate(struc
 #define SetPageUptodate(page)	set_bit(PG_uptodate, &(page)->flags)
 #endif
 #define ClearPageUptodate(page)	clear_bit(PG_uptodate, &(page)->flags)
+#define TestSetPageUptodate(page)	test_and_set_bit(PG_uptodate, &(page)->flags)
 
 #define PageDirty(page)		test_bit(PG_dirty, &(page)->flags)
 #define SetPageDirty(page)	set_bit(PG_dirty, &(page)->flags)