Currently the ppc64 sysfs code registers an entry for each possible cpu in
sysfs, rather than just online cpus.  That makes sense, since the sysfs
entries are needed to control onlining of the cpus.  However, this is done
even if CONFIG_HOTPLUG_CPU is not set, or if it is not a hotplug capable
(DLPAR) machine, which is a bit misleading.  Secondly it also registers all
the other sysfs entries (mostly performance monitoring controls) on all
possible cpus, although they are quite meaningless on non-online cpus.

This patch alters the code to only register sysfs directories at boot for
cpus which are either online or could be onlined (cpu is possible, and
CONFIG_HOTPLUG_CPU and an lpar machine).  Furthermore, the entries apart
from 'online' itself and 'physical_id' are only registered for online CPUs
(and deregistered again if a cpu goes offline).

Currently the ppc64 sysfs code registers an entry for each possible cpu in
sysfs, rather than just online cpus.  That makes sense, since the sysfs
entries are needed to control onlining of the cpus.  However, this is done
even if CONFIG_HOTPLUG_CPU is not set, or if it is not a hotplug capable
(DLPAR) machine, which is a bit misleading.  Secondly it also registers all
the other sysfs entries (mostly performance monitoring controls) on all
possible cpus, although they are quite meaningless on non-online cpus.

This patch alters the code to only register sysfs directories at boot for
cpus which are either online or could be onlined (cpu is possible, and
CONFIG_HOTPLUG_CPU and an lpar machine).  Furthermore, the entries apart
from 'online' itself and 'physical_id' are only registered for online CPUs
(and deregistered again if a cpu goes offline).
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>