linux.git/mm/memory_hotplug.c, branch v3.9-rc2

mm/memory_hotplug: use pgdat_end_pfn() instead of open coding the same.

2013-02-24T01:50:21+00:00

Replace open coded pgdat_end_pfn() with helper function.

Signed-off-by: Cody P Schafer 
Cc: David Hansen 
Cc: Catalin Marinas 
Cc: Johannes Weiner 
Cc: Mel Gorman 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/memory_hotplug: use ensure_zone_is_initialized()

2013-02-24T01:50:21+00:00

Remove open coding of ensure_zone_is_initialzied().

Signed-off-by: Cody P Schafer 
Cc: David Hansen 
Cc: Catalin Marinas 
Cc: Johannes Weiner 
Cc: Mel Gorman 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: add helper ensure_zone_is_initialized()

2013-02-24T01:50:21+00:00

ensure_zone_is_initialized() checks if a zone is in a empty & not
initialized state (typically occuring after it is created in memory
hotplugging), and, if so, calls init_currently_empty_zone() to
initialize the zone.

Signed-off-by: Cody P Schafer 
Cc: David Hansen 
Cc: Catalin Marinas 
Cc: Johannes Weiner 
Cc: Mel Gorman 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: add & use zone_end_pfn() and zone_spans_pfn()

2013-02-24T01:50:20+00:00

Add 2 helpers (zone_end_pfn() and zone_spans_pfn()) to reduce code
duplication.

This also switches to using them in compaction (where an additional
variable needed to be renamed), page_alloc, vmstat, memory_hotplug, and
kmemleak.

Note that in compaction.c I avoid calling zone_end_pfn() repeatedly
because I expect at some point the sycronization issues with start_pfn &
spanned_pages will need fixing, either by actually using the seqlock or
clever memory barrier usage.

Signed-off-by: Cody P Schafer 
Cc: David Hansen 
Cc: Catalin Marinas 
Cc: Johannes Weiner 
Cc: Mel Gorman 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: remove offlining arg to migrate_pages

2013-02-24T01:50:19+00:00

No functional change, but the only purpose of the offlining argument to
migrate_pages() etc, was to ensure that __unmap_and_move() could migrate a
KSM page for memory hotremove (which took ksm_thread_mutex) but not for
other callers.  Now all cases are safe, remove the arg.

Signed-off-by: Hugh Dickins 
Cc: Rik van Riel 
Cc: Petr Holasek 
Cc: Andrea Arcangeli 
Cc: Izik Eidus 
Cc: Gerald Schaefer 
Cc: KOSAKI Motohiro 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: increase totalram_pages when free pages allocated by bootmem allocator

2013-02-24T01:50:15+00:00

Function put_page_bootmem() is used to free pages allocated by bootmem
allocator, so it should increase totalram_pages when freeing pages into
the buddy system.

Signed-off-by: Jiang Liu 
Cc: Wen Congyang 
Cc: David Rientjes 
Cc: Jiang Liu 
Cc: Maciej Rutecki 
Cc: Chris Clayton 
Cc: "Rafael J . Wysocki" 
Cc: Mel Gorman 
Cc: Minchan Kim 
Cc: KAMEZAWA Hiroyuki 
Cc: Michal Hocko 
Cc: Jianguo Wu 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

cpu-hotplug,memory-hotplug: clear cpu_to_node() when offlining the node

2013-02-24T01:50:13+00:00

When the node is offlined, there is no memory/cpu on the node.  If a
sleep task runs on a cpu of this node, it will be migrated to the cpu on
the other node.  So we can clear cpu-to-node mapping.

[akpm@linux-foundation.org: numa_clear_node() and numa_set_node() can no longer be __cpuinit]
Signed-off-by: Wen Congyang 
Signed-off-by: Tang Chen 
Cc: Yasuaki Ishimatsu 
Cc: David Rientjes 
Cc: Jiang Liu 
Cc: Minchan Kim 
Cc: KOSAKI Motohiro 
Cc: Mel Gorman 
Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: "H. Peter Anvin" 
Cc: Peter Zijlstra 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

memory-hotplug: export the function try_offline_node()

2013-02-24T01:50:13+00:00

try_offline_node() will be needed in the tristate
drivers/acpi/processor_driver.c.

The node will be offlined when all memory/cpu on the node have been
hotremoved.  So we need the function try_offline_node() in cpu-hotplug
path.

If the memory-hotplug is disabled, and cpu-hotplug is enabled

1. no memory no the node
   we don't online the node, and cpu's node is the nearest node.

2. the node contains some memory
   the node has been onlined, and cpu's node is still needed
   to migrate the sleep task on the cpu to the same node.

So we do nothing in try_offline_node() in this case.

[rientjes@google.com: export the function try_offline_node() fix]
Signed-off-by: Wen Congyang 
Signed-off-by: Tang Chen 
Cc: Yasuaki Ishimatsu 
Cc: David Rientjes 
Cc: Jiang Liu 
Cc: Minchan Kim 
Cc: KOSAKI Motohiro 
Cc: Mel Gorman 
Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: "H. Peter Anvin" 
Cc: Peter Zijlstra 
Cc: Len Brown 
Signed-off-by: David Rientjes 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

memory-hotplug: do not allocate pgdat if it was not freed when offline.

2013-02-24T01:50:13+00:00

Since there is no way to guarentee the address of pgdat/zone is not on
stack of any kernel threads or used by other kernel objects without
reference counting or other symchronizing method, we cannot reset
node_data and free pgdat when offlining a node.  Just reset pgdat to 0
and reuse the memory when the node is online again.

The problem is suggested by Kamezawa Hiroyuki.  The idea is from Wen
Congyang.

NOTE: If we don't reset pgdat to 0, the WARN_ON in free_area_init_node()
      will be triggered.

[akpm@linux-foundation.org: fix warning when CONFIG_NEED_MULTIPLE_NODES=n]
[akpm@linux-foundation.org: fix the warning again again]
Signed-off-by: Tang Chen 
Reviewed-by: Wen Congyang 
Cc: KOSAKI Motohiro 
Cc: Jiang Liu 
Cc: Jianguo Wu 
Cc: Kamezawa Hiroyuki 
Cc: Lai Jiangshan 
Cc: Wu Jianguo 
Cc: Yasuaki Ishimatsu 
Cc: Ingo Molnar 
Cc: Thomas Gleixner 
Cc: "H. Peter Anvin" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

memory-hotplug: free node_data when a node is offlined

2013-02-24T01:50:13+00:00

We call hotadd_new_pgdat() to allocate memory to store node_data.  So we
should free it when removing a node.

Signed-off-by: Wen Congyang 
Signed-off-by: Tang Chen 
Reviewed-by: Kamezawa Hiroyuki 
Cc: KOSAKI Motohiro 
Cc: Jiang Liu 
Cc: Jianguo Wu 
Cc: Lai Jiangshan 
Cc: Wu Jianguo 
Cc: Yasuaki Ishimatsu 
Cc: Ingo Molnar 
Cc: Thomas Gleixner 
Cc: "H. Peter Anvin" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds