tree 525b1c356df5d1c977dc952c4501f79ff1325db3
parent de300974761d92f71cb583730ac9e1d4eb1b7156
author Michael Ellerman <michael@ellerman.id.au> 1301950647 +0000
committer Benjamin Herrenschmidt <benh@kernel.crashing.org> 1303282878 +1000

powerpc/nohash: Allocate stale_map[cpu] on CPU_UP_PREPARE not CPU_ONLINE

Currently we allocate the stale_map for a cpu when it comes online,
this leaves open a small window where a process can be scheduled
on the cpu before the stale_map is allocated. Instead allocate
the stale_map at CPU_UP_PREPARE time, that way it will be always
available before tasks start running.

It is possible the cpu fails to come up, in which case we should free
the stale_map, so add a CPU_UP_CANCELED case to do that.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>