From 2aac5f19763ea460d20ecdbe0c8f192abdd65e6f Mon Sep 17 00:00:00 2001
From: Mel Gorman <mel@csn.ul.ie>
Date: Wed, 28 Nov 2007 16:21:13 -0800
Subject: [PATCH] --- yaml --- r: 74345 b: refs/heads/master c:
 ba72cb8cb0cdc0a65b3abe9a387f1a26bfd49b8a h: refs/heads/master i:   74343:
 faf90db35839f83bad9a3be684094f385ccef0f1 v: v3

---
 [refs]                     |  2 +-
 trunk/arch/powerpc/Kconfig |  5 +++++
 trunk/mm/page_alloc.c      | 23 +++++++++++++++++++++--
 3 files changed, 27 insertions(+), 3 deletions(-)

diff --git a/[refs] b/[refs]
index 1692f41ce665..6bd463d5c648 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: ee592a5bd5180cc1ffaf5acd7bf1e91e0d854a08
+refs/heads/master: ba72cb8cb0cdc0a65b3abe9a387f1a26bfd49b8a
diff --git a/trunk/arch/powerpc/Kconfig b/trunk/arch/powerpc/Kconfig
index 18f397ca05ef..232c298c933f 100644
--- a/trunk/arch/powerpc/Kconfig
+++ b/trunk/arch/powerpc/Kconfig
@@ -187,6 +187,11 @@ config FORCE_MAX_ZONEORDER
 	default "9" if PPC_64K_PAGES
 	default "13"
 
+config HUGETLB_PAGE_SIZE_VARIABLE
+	bool
+	depends on HUGETLB_PAGE
+	default y
+
 config MATH_EMULATION
 	bool "Math emulation"
 	depends on 4xx || 8xx || E200 || PPC_MPC832x || E500
diff --git a/trunk/mm/page_alloc.c b/trunk/mm/page_alloc.c
index 4ffed1cd158b..b5a58d476c1a 100644
--- a/trunk/mm/page_alloc.c
+++ b/trunk/mm/page_alloc.c
@@ -3265,6 +3265,16 @@ static void inline setup_usemap(struct pglist_data *pgdat,
 #endif /* CONFIG_SPARSEMEM */
 
 #ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
+
+/* Return a sensible default order for the pageblock size. */
+static inline int pageblock_default_order(void)
+{
+	if (HPAGE_SHIFT > PAGE_SHIFT)
+		return HUGETLB_PAGE_ORDER;
+
+	return MAX_ORDER-1;
+}
+
 /* Initialise the number of pages represented by NR_PAGEBLOCK_BITS */
 static inline void __init set_pageblock_order(unsigned int order)
 {
@@ -3280,7 +3290,16 @@ static inline void __init set_pageblock_order(unsigned int order)
 }
 #else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
 
-/* Defined this way to avoid accidently referencing HUGETLB_PAGE_ORDER */
+/*
+ * When CONFIG_HUGETLB_PAGE_SIZE_VARIABLE is not set, set_pageblock_order()
+ * and pageblock_default_order() are unused as pageblock_order is set
+ * at compile-time. See include/linux/pageblock-flags.h for the values of
+ * pageblock_order based on the kernel config
+ */
+static inline int pageblock_default_order(unsigned int order)
+{
+	return MAX_ORDER-1;
+}
 #define set_pageblock_order(x)	do {} while (0)
 
 #endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
@@ -3365,7 +3384,7 @@ static void __meminit free_area_init_core(struct pglist_data *pgdat,
 		if (!size)
 			continue;
 
-		set_pageblock_order(HUGETLB_PAGE_ORDER);
+		set_pageblock_order(pageblock_default_order());
 		setup_usemap(pgdat, zone, size);
 		ret = init_currently_empty_zone(zone, zone_start_pfn,
 						size, MEMMAP_EARLY);