[IA64] Count disabled cpus as potential hot-pluggable CPUs
commita6b14fa6fdc01ab3519c2729624f808677539b59
authorAshok Raj <ashok.raj@intel.com>
Tue, 14 Feb 2006 23:01:12 +0000 (14 15:01 -0800)
committerTony Luck <tony.luck@intel.com>
Tue, 14 Feb 2006 23:37:58 +0000 (14 15:37 -0800)
tree5bf76be44b0c9c7f80612ac71a1b1a4390decd7d
parent69aa234b918c0d9bc4a20cd6d4453aaa3418f457
[IA64] Count disabled cpus as potential hot-pluggable CPUs

Have a facility to account for potentially hot-pluggable CPUs. ACPI doesnt
give a determinstic method to find hot-pluggable CPUs. Hence we use 2 methods
to assist.

- BIOS can mark potentially hot-pluggable CPUs as disabled in the MADT tables.
- User can specify the number of hot-pluggable CPUs via parameter
  additional_cpus=X

The option is enabled only if ACPI_CONFIG_HOTPLUG_CPU=y which enables the
physical hotplug option. Without which user can still use logical onlining
and offlining of CPUs by enabling CONFIG_HOTPLUG_CPU=y

Adds more bits to cpu_possible_map for potentially hot-pluggable cpus.

Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
arch/ia64/kernel/acpi.c
arch/ia64/kernel/setup.c
include/asm-ia64/acpi.h