Joonsoo Kim ad2c814441 topology: add support for node_to_mem_node() to determine the fallback node ... Anton noticed (http://www.spinics.net/lists/linux-mm/msg67489.html) that on ppc LPARs with memoryless nodes, a large amount of memory was consumed by slabs and was marked unreclaimable. He tracked it down to slab deactivations in the SLUB core when we allocate remotely, leading to poor efficiency always when memoryless nodes are present. After much discussion, Joonsoo provided a few patches that help significantly. They don't resolve the problem altogether: - memory hotplug still needs testing, that is when a memoryless node becomes memory-ful, we want to dtrt - there are other reasons for going off-node than memoryless nodes, e.g., fully exhausted local nodes Neither case is resolved with this series, but I don't think that should block their acceptance, as they can be explored/resolved with follow-on patches. The series consists of: [1/3] topology: add support for node_to_mem_node() to determine the fallback node [2/3] slub: fallback to node_to_mem_node() node if allocating on memoryless node - Joonsoo's patches to cache the nearest node with memory for each NUMA node [3/3] Partial revert of 81c98869fa (""kthread: ensure locality of task_struct allocations") - At Tejun's request, keep the knowledge of memoryless node fallback to the allocator core. This patch (of 3): We need to determine the fallback node in slub allocator if the allocation target node is memoryless node. Without it, the SLUB wrongly select the node which has no memory and can't use a partial slab, because of node mismatch. Introduced function, node_to_mem_node(X), will return a node Y with memory that has the nearest distance. If X is memoryless node, it will return nearest distance node, but, if X is normal node, it will return itself. We will use this function in following patch to determine the fallback node. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com> Cc: David Rientjes <rientjes@google.com> Cc: Han Pingtian <hanpt@linux.vnet.ibm.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Anton Blanchard <anton@samba.org> Cc: Christoph Lameter <cl@linux.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2014-10-09 22:25:51 -04:00
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acpi
asm-generic	Merge branch 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2014-10-09 06:30:57 -04:00
clocksource
crypto
drm
dt-bindings	ARM: SoC DT updates for 3.18	2014-10-08 17:22:23 -04:00
keys
kvm
linux	topology: add support for node_to_mem_node() to determine the fallback node	2014-10-09 22:25:51 -04:00
math-emu
media
memory
misc
net	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next	2014-10-08 21:40:54 -04:00
pcmcia
ras
rdma
rxrpc
scsi	Merge remote-tracking branch 'scsi-queue/drivers-for-3.18' into for-linus	2014-10-07 13:48:12 -07:00
soc/tegra
sound
target
trace	Merge tag 'f2fs-for-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs	2014-10-08 12:53:15 -04:00
uapi	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next	2014-10-08 21:40:54 -04:00
video
xen
Kbuild