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-rw-r--r--mm/Kconfig51
1 files changed, 42 insertions, 9 deletions
diff --git a/mm/Kconfig b/mm/Kconfig
index 8028dcc6615c..eb69f352401d 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -20,7 +20,7 @@ config FLATMEM_MANUAL
Some users of more advanced features like NUMA and
memory hotplug may have different options here.
- DISCONTIGMEM is an more mature, better tested system,
+ DISCONTIGMEM is a more mature, better tested system,
but is incompatible with memory hotplug and may suffer
decreased performance over SPARSEMEM. If unsure between
"Sparse Memory" and "Discontiguous Memory", choose
@@ -153,11 +153,18 @@ config MOVABLE_NODE
help
Allow a node to have only movable memory. Pages used by the kernel,
such as direct mapping pages cannot be migrated. So the corresponding
- memory device cannot be hotplugged. This option allows users to
- online all the memory of a node as movable memory so that the whole
- node can be hotplugged. Users who don't use the memory hotplug
- feature are fine with this option on since they don't online memory
- as movable.
+ memory device cannot be hotplugged. This option allows the following
+ two things:
+ - When the system is booting, node full of hotpluggable memory can
+ be arranged to have only movable memory so that the whole node can
+ be hot-removed. (need movable_node boot option specified).
+ - After the system is up, the option allows users to online all the
+ memory of a node as movable memory so that the whole node can be
+ hot-removed.
+
+ Users who don't use the memory hotplug feature are fine with this
+ option on since they don't specify movable_node boot option or they
+ don't online memory as movable.
Say Y here if you want to hotplug a whole node.
Say N here if you want kernel to use memory on all nodes evenly.
@@ -183,7 +190,7 @@ config MEMORY_HOTPLUG_SPARSE
config MEMORY_HOTREMOVE
bool "Allow for memory hot remove"
select MEMORY_ISOLATION
- select HAVE_BOOTMEM_INFO_NODE if X86_64
+ select HAVE_BOOTMEM_INFO_NODE if (X86_64 || PPC64)
depends on MEMORY_HOTPLUG && ARCH_ENABLE_MEMORY_HOTREMOVE
depends on MIGRATION
@@ -211,9 +218,11 @@ config SPLIT_PTLOCK_CPUS
int
default "999999" if ARM && !CPU_CACHE_VIPT
default "999999" if PARISC && !PA20
- default "999999" if DEBUG_SPINLOCK || DEBUG_LOCK_ALLOC
default "4"
+config ARCH_ENABLE_SPLIT_PMD_PTLOCK
+ boolean
+
#
# support for memory balloon compaction
config BALLOON_COMPACTION
@@ -245,7 +254,7 @@ config COMPACTION
config MIGRATION
bool "Page migration"
def_bool y
- depends on NUMA || ARCH_ENABLE_MEMORY_HOTREMOVE || COMPACTION || CMA
+ depends on (NUMA || ARCH_ENABLE_MEMORY_HOTREMOVE || COMPACTION || CMA) && MMU
help
Allows the migration of the physical location of pages of processes
while the virtual addresses are not changed. This is useful in
@@ -478,6 +487,30 @@ config FRONTSWAP
If unsure, say Y to enable frontswap.
+config CMA
+ bool "Contiguous Memory Allocator"
+ depends on HAVE_MEMBLOCK && MMU
+ select MIGRATION
+ select MEMORY_ISOLATION
+ help
+ This enables the Contiguous Memory Allocator which allows other
+ subsystems to allocate big physically-contiguous blocks of memory.
+ CMA reserves a region of memory and allows only movable pages to
+ be allocated from it. This way, the kernel can use the memory for
+ pagecache and when a subsystem requests for contiguous area, the
+ allocated pages are migrated away to serve the contiguous request.
+
+ If unsure, say "n".
+
+config CMA_DEBUG
+ bool "CMA debug messages (DEVELOPMENT)"
+ depends on DEBUG_KERNEL && CMA
+ help
+ Turns on debug messages in CMA. This produces KERN_DEBUG
+ messages for every CMA call as well as various messages while
+ processing calls such as dma_alloc_from_contiguous().
+ This option does not affect warning and error messages.
+
config ZBUD
tristate
default n