diff options
author | Lai Jiangshan <laijs@cn.fujitsu.com> | 2012-12-12 04:03:16 +0400 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-12-12 05:22:28 +0400 |
commit | 511c2aba8f07fc45bdcba548cb63f7b8a450c6dc (patch) | |
tree | 6a1a853e60e0004f5895d78231ed1bea33fecaac /include | |
parent | fcf07d22f089856631b52a75c35ba3c33b70a1b4 (diff) | |
download | linux-511c2aba8f07fc45bdcba548cb63f7b8a450c6dc.tar.xz |
mm, memory-hotplug: dynamic configure movable memory and portion memory
Add online_movable and online_kernel for logic memory hotplug. This is
the dynamic version of "movablecore" & "kernelcore".
We have the same reason to introduce it as to introduce "movablecore" &
"kernelcore". It has the same motive as "movablecore" & "kernelcore", but
it is dynamic/running-time:
o We can configure memory as kernelcore or movablecore after boot.
Userspace workload is increased, we need more hugepage, we can't use
"online_movable" to add memory and allow the system use more
THP(transparent-huge-page), vice-verse when kernel workload is increase.
Also help for virtualization to dynamic configure host/guest's memory,
to save/(reduce waste) memory.
Memory capacity on Demand
o When a new node is physically online after boot, we need to use
"online_movable" or "online_kernel" to configure/portion it as we
expected when we logic-online it.
This configuration also helps for physically-memory-migrate.
o all benefit as the same as existed "movablecore" & "kernelcore".
o Preparing for movable-node, which is very important for power-saving,
hardware partitioning and high-available-system(hardware fault
management).
(Note, we don't introduce movable-node here.)
Action behavior:
When a memoryblock/memorysection is onlined by "online_movable", the kernel
will not have directly reference to the page of the memoryblock,
thus we can remove that memory any time when needed.
When it is online by "online_kernel", the kernel can use it.
When it is online by "online", the zone type doesn't changed.
Current constraints:
Only the memoryblock which is adjacent to the ZONE_MOVABLE
can be online from ZONE_NORMAL to ZONE_MOVABLE.
[akpm@linux-foundation.org: use min_t, cleanups]
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Jiang Liu <jiang.liu@huawei.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include')
-rw-r--r-- | include/linux/memory_hotplug.h | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h index 95573ec4ee6c..4a45c4e50025 100644 --- a/include/linux/memory_hotplug.h +++ b/include/linux/memory_hotplug.h @@ -26,6 +26,13 @@ enum { MEMORY_HOTPLUG_MAX_BOOTMEM_TYPE = NODE_INFO, }; +/* Types for control the zone type of onlined memory */ +enum { + ONLINE_KEEP, + ONLINE_KERNEL, + ONLINE_MOVABLE, +}; + /* * pgdat resizing functions */ @@ -46,6 +53,10 @@ void pgdat_resize_init(struct pglist_data *pgdat) } /* * Zone resizing functions + * + * Note: any attempt to resize a zone should has pgdat_resize_lock() + * zone_span_writelock() both held. This ensure the size of a zone + * can't be changed while pgdat_resize_lock() held. */ static inline unsigned zone_span_seqbegin(struct zone *zone) { @@ -71,7 +82,7 @@ extern int zone_grow_free_lists(struct zone *zone, unsigned long new_nr_pages); extern int zone_grow_waitqueues(struct zone *zone, unsigned long nr_pages); extern int add_one_highpage(struct page *page, int pfn, int bad_ppro); /* VM interface that may be used by firmware interface */ -extern int online_pages(unsigned long, unsigned long); +extern int online_pages(unsigned long, unsigned long, int); extern void __offline_isolated_pages(unsigned long, unsigned long); typedef void (*online_page_callback_t)(struct page *page); |