in their physical address spaces, and this option provides
more efficient handling of these holes. However, the vast
majority of hardware has quite flat address spaces, and
- can have degraded performance from extra overhead that
+ can have degraded performance from the extra overhead that
this option imposes.
Many NUMA configurations will have this as the only option.
def_bool y
depends on SPARSEMEM && !SPARSEMEM_STATIC
+config SPARSEMEM_VMEMMAP_ENABLE
+ def_bool n
+
+config SPARSEMEM_VMEMMAP
+ bool "Sparse Memory virtual memmap"
+ depends on SPARSEMEM && SPARSEMEM_VMEMMAP_ENABLE
+ default y
+ help
+ SPARSEMEM_VMEMMAP uses a virtually mapped memmap to optimise
+ pfn_to_page and page_to_pfn operations. This is the most
+ efficient option when sufficient kernel resources are available.
+
# eventually, we can have this option just 'select SPARSEMEM'
config MEMORY_HOTPLUG
bool "Allow for memory hot-add"
depends on SPARSEMEM || X86_64_ACPI_NUMA
- depends on HOTPLUG && !SOFTWARE_SUSPEND && ARCH_ENABLE_MEMORY_HOTPLUG
- depends on (IA64 || X86 || PPC64 || SUPERH)
+ depends on HOTPLUG && !HIBERNATION && ARCH_ENABLE_MEMORY_HOTPLUG
+ depends on (IA64 || X86 || PPC64 || SUPERH || S390)
comment "Memory hotplug is currently incompatible with Software Suspend"
- depends on SPARSEMEM && HOTPLUG && SOFTWARE_SUSPEND
+ depends on SPARSEMEM && HOTPLUG && HIBERNATION
config MEMORY_HOTPLUG_SPARSE
def_bool y
depends on SPARSEMEM && MEMORY_HOTPLUG
+config MEMORY_HOTREMOVE
+ bool "Allow for memory hot remove"
+ 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 || !NUMA || !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.
default "0" if !ZONE_DMA
default "1"
+config BOUNCE
+ def_bool y
+ depends on BLOCK && MMU && (ZONE_DMA || HIGHMEM)
+
config NR_QUICK
int
depends on QUICKLIST
- default "2" if (SUPERH && !SUPERH64)
+ default "2" if SUPERH || AVR32
default "1"
+
+config VIRT_TO_BUS
+ def_bool y
+ depends on !ARCH_NO_VIRT_TO_BUS