x86: modify Kconfig to allow up to 4096 cpus

* Increase the limit of NR_CPUS to 4096 and introduce a boolean
    called "MAXSMP" which when set (e.g. "allyesconfig"), will set
    NR_CPUS = 4096 and NODES_SHIFT = 9 (512).

  * Changed max setting for NODES_SHIFT from 15 to 9 to accurately
    reflect the real limit.

Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Mike Travis 2008-05-12 21:21:12 +02:00 committed by Ingo Molnar
parent 7496b60654
commit 1184dc2ffe

View file

@ -561,20 +561,35 @@ config SWIOTLB
config IOMMU_HELPER
def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB)
config MAXSMP
bool "Configure Maximum number of SMP Processors and NUMA Nodes"
depends on X86_64 && SMP
default n
help
Configure maximum number of CPUS and NUMA Nodes for this architecture.
If unsure, say N.
if MAXSMP
config NR_CPUS
int "Maximum number of CPUs (2-255)"
range 2 255
int
default "4096"
endif
if !MAXSMP
config NR_CPUS
int "Maximum number of CPUs (2-4096)"
range 2 4096
depends on SMP
default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
default "8"
help
This allows you to specify the maximum number of CPUs which this
kernel will support. The maximum supported value is 255 and the
kernel will support. The maximum supported value is 4096 and the
minimum value which makes sense is 2.
This is purely to save memory - each supported CPU adds
approximately eight kilobytes to the kernel image.
endif
config SCHED_SMT
bool "SMT (Hyperthreading) scheduler support"
@ -965,13 +980,25 @@ config NUMA_EMU
into virtual nodes when booted with "numa=fake=N", where N is the
number of nodes. This is only useful for debugging.
if MAXSMP
config NODES_SHIFT
int "Max num nodes shift(1-9)"
range 1 9 if X86_64
int
default "9"
endif
if !MAXSMP
config NODES_SHIFT
int "Maximum NUMA Nodes (as a power of 2)"
range 1 9 if X86_64
default "6" if X86_64
default "4" if X86_NUMAQ
default "3"
depends on NEED_MULTIPLE_NODES
help
Specify the maximum number of NUMA Nodes available on the target
system. Increases memory reserved to accomodate various tables.
endif
config HAVE_ARCH_BOOTMEM_NODE
def_bool y