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
efficient option when sufficient kernel resources are available.
config HAVE_MEMBLOCK
- boolean
+ bool
config HAVE_MEMBLOCK_NODE_MAP
- boolean
+ bool
+
+config HAVE_MEMBLOCK_PHYS_MAP
+ bool
+
+config HAVE_GENERIC_RCU_GUP
+ bool
config ARCH_DISCARD_MEMBLOCK
- boolean
+ bool
config NO_BOOTMEM
- boolean
+ bool
config MEMORY_ISOLATION
- boolean
+ bool
config MOVABLE_NODE
- boolean "Enable to assign a node which has only movable memory"
+ bool "Enable to assign a node which has only movable memory"
depends on HAVE_MEMBLOCK
depends on NO_BOOTMEM
depends on X86_64
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.
config MEMORY_HOTPLUG
bool "Allow for memory hot-add"
depends on SPARSEMEM || X86_64_ACPI_NUMA
- depends on HOTPLUG && ARCH_ENABLE_MEMORY_HOTPLUG
+ depends on ARCH_ENABLE_MEMORY_HOTPLUG
depends on (IA64 || X86 || PPC_BOOK3S_64 || SUPERH || S390)
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
-#
-# If we have space for more page flags then we can enable additional
-# optimizations and functionality.
-#
-# Regular Sparsemem takes page flag bits for the sectionid if it does not
-# use a virtual memmap. Disable extended page flags for 32 bit platforms
-# that require the use of a sectionid in the page flags.
-#
-config PAGEFLAGS_EXTENDED
- def_bool y
- depends on 64BIT || SPARSEMEM_VMEMMAP || !SPARSEMEM
-
# Heavily threaded applications may benefit from splitting the mm-wide
# page_table_lock, so that faults on different parts of the user address
# space can be handled with less contention: split it at this NR_CPUS.
#
config SPLIT_PTLOCK_CPUS
int
+ default "999999" if !MMU
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
+ bool
+
+#
+# support for memory balloon
+config MEMORY_BALLOON
+ bool
+
#
# support for memory balloon compaction
config BALLOON_COMPACTION
bool "Allow for balloon memory compaction/migration"
def_bool y
- depends on COMPACTION && VIRTIO_BALLOON
+ depends on COMPACTION && MEMORY_BALLOON
help
Memory fragmentation introduced by ballooning might reduce
significantly the number of 2MB contiguous memory blocks that can be
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
pages as migration can relocate pages to satisfy a huge page
allocation instead of reclaiming.
+config ARCH_ENABLE_HUGEPAGE_MIGRATION
+ bool
+
config PHYS_ADDR_T_64BIT
def_bool 64BIT || ARCH_PHYS_ADDR_T_64BIT
# On the 'tile' arch, USB OHCI needs the bounce pool since tilegx will often
# have more than 4GB of memory, but we don't currently use the IOTLB to present
# a 32-bit address to OHCI. So we need to use a bounce pool instead.
-#
-# We also use the bounce pool to provide stable page writes for jbd. jbd
-# initiates buffer writeback without locking the page or setting PG_writeback,
-# and fixing that behavior (a second time; jbd2 doesn't have this problem) is
-# a major rework effort. Instead, use the bounce buffer to snapshot pages
-# (until jbd goes away). The only jbd user is ext3.
config NEED_BOUNCE_POOL
bool
- default y if (TILE && USB_OHCI_HCD) || (BLK_DEV_INTEGRITY && JBD)
+ default y if TILE && USB_OHCI_HCD
config NR_QUICK
int
config MMU_NOTIFIER
bool
+ select SRCU
config KSM
bool "Enable KSM for page merging"
depends on ARCH_SUPPORTS_MEMORY_FAILURE
bool "Enable recovery from hardware memory errors"
select MEMORY_ISOLATION
+ select RAS
help
Enables code to recover from some memory failures on systems
with MCA recovery. This allows a system to continue running
benefit.
endchoice
-config CROSS_MEMORY_ATTACH
- bool "Cross Memory Support"
- depends on MMU
- default y
- help
- Enabling this option adds the system calls process_vm_readv and
- process_vm_writev which allow a process with the correct privileges
- to directly read from or write to to another process's address space.
- See the man page for more details.
-
#
# UP and nommu archs use km based percpu allocator
#
and swap data is stored as normal on the matching swap device.
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 CMA_DEBUGFS
+ bool "CMA debugfs interface"
+ depends on CMA && DEBUG_FS
+ help
+ Turns on the DebugFS interface for CMA.
+
+config CMA_AREAS
+ int "Maximum count of the CMA areas"
+ depends on CMA
+ default 7
+ help
+ CMA allows to create CMA areas for particular purpose, mainly,
+ used as device private area. This parameter sets the maximum
+ number of CMA area in the system.
+
+ If unsure, leave the default value "7".
+
+config MEM_SOFT_DIRTY
+ bool "Track memory changes"
+ depends on CHECKPOINT_RESTORE && HAVE_ARCH_SOFT_DIRTY && PROC_FS
+ select PROC_PAGE_MONITOR
+ help
+ This option enables memory changes tracking by introducing a
+ soft-dirty bit on pte-s. This bit it set when someone writes
+ into a page just as regular dirty bit, but unlike the latter
+ it can be cleared by hands.
+
+ See Documentation/vm/soft-dirty.txt for more details.
+
+config ZSWAP
+ bool "Compressed cache for swap pages (EXPERIMENTAL)"
+ depends on FRONTSWAP && CRYPTO=y
+ select CRYPTO_LZO
+ select ZPOOL
+ default n
+ help
+ A lightweight compressed cache for swap pages. It takes
+ pages that are in the process of being swapped out and attempts to
+ compress them into a dynamically allocated RAM-based memory pool.
+ This can result in a significant I/O reduction on swap device and,
+ in the case where decompressing from RAM is faster that swap device
+ reads, can also improve workload performance.
+
+ This is marked experimental because it is a new feature (as of
+ v3.11) that interacts heavily with memory reclaim. While these
+ interactions don't cause any known issues on simple memory setups,
+ they have not be fully explored on the large set of potential
+ configurations and workloads that exist.
+
+config ZPOOL
+ tristate "Common API for compressed memory storage"
+ default n
+ help
+ Compressed memory storage API. This allows using either zbud or
+ zsmalloc.
+
+config ZBUD
+ tristate "Low density storage for compressed pages"
+ default n
+ help
+ A special purpose allocator for storing compressed pages.
+ It is designed to store up to two compressed pages per physical
+ page. While this design limits storage density, it has simple and
+ deterministic reclaim properties that make it preferable to a higher
+ density approach when reclaim will be used.
+
+config ZSMALLOC
+ tristate "Memory allocator for compressed pages"
+ depends on MMU
+ default n
+ help
+ zsmalloc is a slab-based memory allocator designed to store
+ compressed RAM pages. zsmalloc uses virtual memory mapping
+ in order to reduce fragmentation. However, this results in a
+ non-standard allocator interface where a handle, not a pointer, is
+ returned by an alloc(). This handle must be mapped in order to
+ access the allocated space.
+
+config PGTABLE_MAPPING
+ bool "Use page table mapping to access object in zsmalloc"
+ depends on ZSMALLOC
+ help
+ By default, zsmalloc uses a copy-based object mapping method to
+ access allocations that span two pages. However, if a particular
+ architecture (ex, ARM) performs VM mapping faster than copying,
+ then you should select this. This causes zsmalloc to use page table
+ mapping rather than copying for object mapping.
+
+ You can check speed with zsmalloc benchmark:
+ https://github.com/spartacus06/zsmapbench
+
+config ZSMALLOC_STAT
+ bool "Export zsmalloc statistics"
+ depends on ZSMALLOC
+ select DEBUG_FS
+ help
+ This option enables code in the zsmalloc to collect various
+ statistics about whats happening in zsmalloc and exports that
+ information to userspace via debugfs.
+ If unsure, say N.
+
+config GENERIC_EARLY_IOREMAP
+ bool
+
+config MAX_STACK_SIZE_MB
+ int "Maximum user stack size for 32-bit processes (MB)"
+ default 80
+ range 8 256 if METAG
+ range 8 2048
+ depends on STACK_GROWSUP && (!64BIT || COMPAT)
+ help
+ This is the maximum stack size in Megabytes in the VM layout of 32-bit
+ user processes when the stack grows upwards (currently only on parisc
+ and metag arch). The stack will be located at the highest memory
+ address minus the given value, unless the RLIMIT_STACK hard limit is
+ changed to a smaller value in which case that is used.
+
+ A sane initial value is 80 MB.
+
+# For architectures that support deferred memory initialisation
+config ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT
+ bool
+
+config DEFERRED_STRUCT_PAGE_INIT
+ bool "Defer initialisation of struct pages to kswapd"
+ default n
+ depends on ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT
+ depends on MEMORY_HOTPLUG
+ help
+ Ordinarily all struct pages are initialised during early boot in a
+ single thread. On very large machines this can take a considerable
+ amount of time. If this option is set, large machines will bring up
+ a subset of memmap at boot and then initialise the rest in parallel
+ when kswapd starts. This has a potential performance impact on
+ processes running early in the lifetime of the systemm until kswapd
+ finishes the initialisation.
+
+config IDLE_PAGE_TRACKING
+ bool "Enable idle page tracking"
+ depends on SYSFS && MMU
+ select PAGE_EXTENSION if !64BIT
+ help
+ This feature allows to estimate the amount of user pages that have
+ not been touched during a given period of time. This information can
+ be useful to tune memory cgroup limits and/or for job placement
+ within a compute cluster.
+
+ See Documentation/vm/idle_page_tracking.txt for more details.
+
+config ZONE_DEVICE
+ bool "Device memory (pmem, etc...) hotplug support" if EXPERT
+ default !ZONE_DMA
+ depends on !ZONE_DMA
+ depends on MEMORY_HOTPLUG
+ depends on MEMORY_HOTREMOVE
+ depends on X86_64 #arch_add_memory() comprehends device memory
+
+ help
+ Device memory hotplug support allows for establishing pmem,
+ or other device driver discovered memory regions, in the
+ memmap. This allows pfn_to_page() lookups of otherwise
+ "device-physical" addresses which is needed for using a DAX
+ mapping in an O_DIRECT operation, among other things.
+
+ If FS_DAX is enabled, then say Y.
+
+config FRAME_VECTOR
+ bool
projects / firefly-linux-kernel-4.4.55.git / blobdiff