linux-toradex.git/drivers/base/node.c, branch v2.6.33.5

mm: slab-allocate memory section nodemask for large systems

2009-12-15T16:53:20+00:00

Nodemasks should not be allocated on the stack for large systems (when it
is larger than 256 bytes) since there is a threat of overflow.

This patch causes the unregister_mem_sect_under_nodes() nodemask to be
allocated on the stack for smaller systems and be allocated by slab for
larger systems.

GFP_KERNEL is used since remove_memory_block() can block.

Cc: Gary Hade 
Cc: Badari Pulavarty 
Cc: Alex Chiang 
Signed-off-by: David Rientjes 
Cc: Greg Kroah-Hartman 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: add numa node symlink for cpu devices in sysfs

2009-12-15T16:53:18+00:00

You can discover which CPUs belong to a NUMA node by examining
/sys/devices/system/node/node#/

However, it's not convenient to go in the other direction, when looking at
/sys/devices/system/cpu/cpu#/

Yes, you can muck about in sysfs, but adding these symlinks makes life a
lot more convenient.

Signed-off-by: Alex Chiang 
Acked-by: David Rientjes 
Cc: Gary Hade 
Cc: Badari Pulavarty 
Cc: Ingo Molnar 
Cc: David Rientjes 
Cc: Greg KH 
Cc: Randy Dunlap 
Cc: David Rientjes 
Cc: KOSAKI Motohiro 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: refactor unregister_cpu_under_node()

2009-12-15T16:53:17+00:00

By returning early if the node is not online, we can unindent the
interesting code by two levels.

No functional change.

Signed-off-by: Alex Chiang 
Cc: Gary Hade 
Cc: Badari Pulavarty 
Cc: Ingo Molnar 
Cc: David Rientjes 
Cc: Greg KH 
Cc: Randy Dunlap 
Cc: David Rientjes 
Cc: KOSAKI Motohiro 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: refactor register_cpu_under_node()

2009-12-15T16:53:17+00:00

By returning early if the node is not online, we can unindent the
interesting code by one level.

No functional change.

Signed-off-by: Alex Chiang 
Cc: Gary Hade 
Cc: Badari Pulavarty 
Cc: Ingo Molnar 
Cc: David Rientjes 
Cc: Greg KH 
Cc: Randy Dunlap 
Cc: David Rientjes 
Cc: KOSAKI Motohiro 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: add numa node symlink for memory section in sysfs

2009-12-15T16:53:17+00:00

Commit c04fc586c (mm: show node to memory section relationship with
symlinks in sysfs) created symlinks from nodes to memory sections, e.g.

/sys/devices/system/node/node1/memory135 -> ../../memory/memory135

If you're examining the memory section though and are wondering what node
it might belong to, you can find it by grovelling around in sysfs, but
it's a little cumbersome.

Add a reverse symlink for each memory section that points back to the
node to which it belongs.

Signed-off-by: Alex Chiang 
Cc: Gary Hade 
Cc: Badari Pulavarty 
Cc: Ingo Molnar 
Acked-by: David Rientjes 
Cc: Greg KH 
Cc: Randy Dunlap 
Cc: David Rientjes 
Cc: KOSAKI Motohiro 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

hugetlb: offload per node attribute registrations

2009-12-15T16:53:13+00:00

Offload the registration and unregistration of per node hstate sysfs
attributes to a worker thread rather than attempt the
allocation/attachment or detachment/freeing of the attributes in the
context of the memory hotplug handler.

I don't know that this is absolutely required, but the registration can
sleep in allocations and other mem hot plug handlers do it this way.  If
it turns out this is NOT required, we can drop this patch.

N.B.,  Only tested build, boot, libhugetlbfs regression.
       i.e., no memory hotplug testing.

Signed-off-by: Lee Schermerhorn 
Reviewed-by: Andi Kleen 
Cc: KAMEZAWA Hiroyuki 
Cc: Lee Schermerhorn 
Cc: Mel Gorman 
Cc: Randy Dunlap 
Cc: Nishanth Aravamudan 
Cc: David Rientjes 
Cc: Adam Litke 
Cc: Andy Whitcroft 
Cc: Eric Whitney 
Cc: Christoph Lameter 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

hugetlb: handle memory hot-plug events

2009-12-15T16:53:13+00:00

Register per node hstate attributes only for nodes with memory.  As
suggested by David Rientjes.

With Memory Hotplug, memory can be added to a memoryless node and a node
with memory can become memoryless.  Therefore, add a memory on/off-line
notifier callback to [un]register a node's attributes on transition
to/from memoryless state.

N.B.,  Only tested build, boot, libhugetlbfs regression.
       i.e., no memory hotplug testing.

Signed-off-by: Lee Schermerhorn 
Reviewed-by: Andi Kleen 
Acked-by: David Rientjes 
Cc: KAMEZAWA Hiroyuki 
Cc: Lee Schermerhorn 
Cc: Mel Gorman 
Cc: Randy Dunlap 
Cc: Nishanth Aravamudan 
Cc: Adam Litke 
Cc: Andy Whitcroft 
Cc: Eric Whitney 
Cc: Christoph Lameter 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

hugetlb: add per node hstate attributes

2009-12-15T16:53:12+00:00

Add the per huge page size control/query attributes to the per node
sysdevs:

/sys/devices/system/node/node/hugepages/hugepages-/
	nr_hugepages       - r/w
	free_huge_pages    - r/o
	surplus_huge_pages - r/o

The patch attempts to re-use/share as much of the existing global hstate
attribute initialization and handling, and the "nodes_allowed" constraint
processing as possible.

Calling set_max_huge_pages() with no node indicates a change to global
hstate parameters.  In this case, any non-default task mempolicy will be
used to generate the nodes_allowed mask.  A valid node id indicates an
update to that node's hstate parameters, and the count argument specifies
the target count for the specified node.  From this info, we compute the
target global count for the hstate and construct a nodes_allowed node mask
contain only the specified node.

Setting the node specific nr_hugepages via the per node attribute
effectively ignores any task mempolicy or cpuset constraints.

With this patch:

(me):ls /sys/devices/system/node/node0/hugepages/hugepages-2048kB
./  ../  free_hugepages  nr_hugepages  surplus_hugepages

Starting from:
Node 0 HugePages_Total:     0
Node 0 HugePages_Free:      0
Node 0 HugePages_Surp:      0
Node 1 HugePages_Total:     0
Node 1 HugePages_Free:      0
Node 1 HugePages_Surp:      0
Node 2 HugePages_Total:     0
Node 2 HugePages_Free:      0
Node 2 HugePages_Surp:      0
Node 3 HugePages_Total:     0
Node 3 HugePages_Free:      0
Node 3 HugePages_Surp:      0
vm.nr_hugepages = 0

Allocate 16 persistent huge pages on node 2:
(me):echo 16 >/sys/devices/system/node/node2/hugepages/hugepages-2048kB/nr_hugepages

[Note that this is equivalent to:
	numactl -m 2 hugeadmin --pool-pages-min 2M:+16
]

Yields:
Node 0 HugePages_Total:     0
Node 0 HugePages_Free:      0
Node 0 HugePages_Surp:      0
Node 1 HugePages_Total:     0
Node 1 HugePages_Free:      0
Node 1 HugePages_Surp:      0
Node 2 HugePages_Total:    16
Node 2 HugePages_Free:     16
Node 2 HugePages_Surp:      0
Node 3 HugePages_Total:     0
Node 3 HugePages_Free:      0
Node 3 HugePages_Surp:      0
vm.nr_hugepages = 16

Global controls work as expected--reduce pool to 8 persistent huge pages:
(me):echo 8 >/sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages

Node 0 HugePages_Total:     0
Node 0 HugePages_Free:      0
Node 0 HugePages_Surp:      0
Node 1 HugePages_Total:     0
Node 1 HugePages_Free:      0
Node 1 HugePages_Surp:      0
Node 2 HugePages_Total:     8
Node 2 HugePages_Free:      8
Node 2 HugePages_Surp:      0
Node 3 HugePages_Total:     0
Node 3 HugePages_Free:      0
Node 3 HugePages_Surp:      0

Signed-off-by: Lee Schermerhorn 
Acked-by: Mel Gorman 
Reviewed-by: Andi Kleen 
Cc: KAMEZAWA Hiroyuki 
Cc: Randy Dunlap 
Cc: Nishanth Aravamudan 
Cc: David Rientjes 
Cc: Adam Litke 
Cc: Andy Whitcroft 
Cc: Eric Whitney 
Cc: Christoph Lameter 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: oom analysis: add shmem vmstat

2009-09-22T14:17:27+00:00

Recently we encountered OOM problems due to memory use of the GEM cache.
Generally a large amuont of Shmem/Tmpfs pages tend to create a memory
shortage problem.

We often use the following calculation to determine the amount of shmem
pages:

shmem = NR_ACTIVE_ANON + NR_INACTIVE_ANON - NR_ANON_PAGES

however the expression does not consider isolated and mlocked pages.

This patch adds explicit accounting for pages used by shmem and tmpfs.

Signed-off-by: KOSAKI Motohiro 
Acked-by: Rik van Riel 
Reviewed-by: Christoph Lameter 
Acked-by: Wu Fengguang 
Cc: David Rientjes 
Cc: Hugh Dickins 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: oom analysis: Show kernel stack usage in /proc/meminfo and OOM log output

2009-09-22T14:17:27+00:00

The amount of memory allocated to kernel stacks can become significant and
cause OOM conditions.  However, we do not display the amount of memory
consumed by stacks.

Add code to display the amount of memory used for stacks in /proc/meminfo.

Signed-off-by: KOSAKI Motohiro 
Reviewed-by: Christoph Lameter 
Reviewed-by: Minchan Kim 
Reviewed-by: Rik van Riel 
Cc: David Rientjes 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds