cpu_possible_map = cpu_present_map + additional_cpus
(*) Option valid only for following architectures
-- x86_64, ia64, s390
+- x86_64, ia64
ia64 and x86_64 use the number of disabled local apics in ACPI tables MADT
to determine the number of potentially hot-pluggable cpus. The implementation
mark such hot-pluggable cpus as disabled entries, one could use this
parameter "additional_cpus=x" to represent those cpus in the cpu_possible_map.
-s390 uses the number of cpus it detects at IPL time to also the number of bits
-in cpu_possible_map. If it is desired to add additional cpus at a later time
-the number should be specified using this option or the possible_cpus option.
-
possible_cpus=n [s390 only] use this to set hotpluggable cpus.
This option sets possible_cpus bits in
cpu_possible_map. Thus keeping the numbers of bits set
constant even if the machine gets rebooted.
- This option overrides additional_cpus.
CPU maps and such
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