---

yaml
---
r: 198241
b: refs/heads/master
c: e9e96b3
h: refs/heads/master
i:
  198239: d83e277
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 3fe2011ff51e92500010a495df4be86745fbbda9
+refs/heads/master: e9e96b39f932a065e14f5d5bab0797ae261d03b5

trunk/mm/Kconfig

@@ -171,6 +171,15 @@ config SPLIT_PTLOCK_CPUS
 	default "999999" if DEBUG_SPINLOCK || DEBUG_LOCK_ALLOC
 	default "4"
 
+#
+# support for memory compaction
+config COMPACTION
+	bool "Allow for memory compaction"
+	select MIGRATION
+	depends on EXPERIMENTAL && HUGETLB_PAGE && MMU
+	help
+	  Allows the compaction of memory for the allocation of huge pages.
+
 #
 # support for page migration
 #
@@ -180,9 +189,11 @@ config MIGRATION
 	depends on NUMA || ARCH_ENABLE_MEMORY_HOTREMOVE
 	help
 	  Allows the migration of the physical location of pages of processes
-	  while the virtual addresses are not changed. This is useful for
-	  example on NUMA systems to put pages nearer to the processors accessing
-	  the page.
+	  while the virtual addresses are not changed. This is useful in
+	  two situations. The first is on NUMA systems to put pages nearer
+	  to the processors accessing. The second is when allocating huge
+	  pages as migration can relocate pages to satisfy a huge page
+	  allocation instead of reclaiming.
 
 config PHYS_ADDR_T_64BIT
 	def_bool 64BIT || ARCH_PHYS_ADDR_T_64BIT