s390/numa: add core infrastructure

Enable core NUMA support for s390 and add one simple default mode "plain"
that creates one single NUMA node.

This patch contains several changes from Michael Holzheu.

Signed-off-by: Philipp Hachtmann <phacht@linux.vnet.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 37 insertions, 0 deletions

diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 91e8954f1237..25510adb07d3 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -153,6 +153,10 @@ config S390
 	select TTY
 	select VIRT_CPU_ACCOUNTING
 	select VIRT_TO_BUS
+	select ARCH_SUPPORTS_NUMA_BALANCING
+	select ARCH_WANTS_PROT_NUMA_PROT_NONE
+	select HAVE_ARCH_EARLY_PFN_TO_NID
+
 
 config SCHED_OMIT_FRAME_POINTER
 	def_bool y
@@ -386,6 +390,39 @@ config HOTPLUG_CPU
 config SCHED_SMT
 	def_bool n
 
+# Some NUMA nodes have memory ranges that span
+# other nodes.	Even though a pfn is valid and
+# between a node's start and end pfns, it may not
+# reside on that node.	See memmap_init_zone()
+# for details. <- They meant memory holes!
+config NODES_SPAN_OTHER_NODES
+	def_bool NUMA
+
+config NUMA
+	bool "NUMA support"
+	depends on SMP && 64BIT && SCHED_TOPOLOGY
+	default n
+	help
+	  Enable NUMA support
+
+	  This option adds NUMA support to the kernel.
+
+	  An operation mode can be selected by appending
+	  numa=<method> to the kernel command line.
+
+	  The default behaviour is identical to appending numa=plain to
+	  the command line. This will create just one node with all
+	  available memory and all CPUs in it.
+
+config NODES_SHIFT
+	int "Maximum NUMA nodes (as a power of 2)"
+	range 1 10
+	depends on NUMA
+	default "4"
+	help
+	  Specify the maximum number of NUMA nodes available on the target
+	  system. Increases memory reserved to accommodate various tables.
+
 config SCHED_MC
 	def_bool n