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| author | Zhang Zhen <zhenzhang.zhang@huawei.com> | 2014-10-09 15:26:31 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-10-09 22:25:52 -0400 |
| commit | ed2f240094f900833ac06f533ab8bbcf0a1e8199 (patch) | |
| tree | a29d18bd9463645fa6ecdab3dd90945f861097d2 /Documentation/memory-hotplug.txt | |
| parent | cc71aba348906ff93a4ad2f600045ee2d1ecc291 (diff) | |
| download | lwn-ed2f240094f900833ac06f533ab8bbcf0a1e8199.tar.gz lwn-ed2f240094f900833ac06f533ab8bbcf0a1e8199.zip | |
memory-hotplug: add sysfs valid_zones attribute
Currently memory-hotplug has two limits:
1. If the memory block is in ZONE_NORMAL, you can change it to
ZONE_MOVABLE, but this memory block must be adjacent to ZONE_MOVABLE.
2. If the memory block is in ZONE_MOVABLE, you can change it to
ZONE_NORMAL, but this memory block must be adjacent to ZONE_NORMAL.
With this patch, we can easy to know a memory block can be onlined to
which zone, and don't need to know the above two limits.
Updated the related Documentation.
[akpm@linux-foundation.org: use conventional comment layout]
[akpm@linux-foundation.org: fix build with CONFIG_MEMORY_HOTREMOVE=n]
[akpm@linux-foundation.org: remove unused local zone_prev]
Signed-off-by: Zhang Zhen <zhenzhang.zhang@huawei.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Wang Nan <wangnan0@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'Documentation/memory-hotplug.txt')
| -rw-r--r-- | Documentation/memory-hotplug.txt | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/Documentation/memory-hotplug.txt b/Documentation/memory-hotplug.txt index 45134dc23854..ea03abfc97e9 100644 --- a/Documentation/memory-hotplug.txt +++ b/Documentation/memory-hotplug.txt @@ -155,6 +155,7 @@ Under each memory block, you can see 4 files: /sys/devices/system/memory/memoryXXX/phys_device /sys/devices/system/memory/memoryXXX/state /sys/devices/system/memory/memoryXXX/removable +/sys/devices/system/memory/memoryXXX/valid_zones 'phys_index' : read-only and contains memory block id, same as XXX. 'state' : read-write @@ -170,6 +171,15 @@ Under each memory block, you can see 4 files: block is removable and a value of 0 indicates that it is not removable. A memory block is removable only if every section in the block is removable. +'valid_zones' : read-only: designed to show which zones this memory block + can be onlined to. + The first column shows it's default zone. + "memory6/valid_zones: Normal Movable" shows this memoryblock + can be onlined to ZONE_NORMAL by default and to ZONE_MOVABLE + by online_movable. + "memory7/valid_zones: Movable Normal" shows this memoryblock + can be onlined to ZONE_MOVABLE by default and to ZONE_NORMAL + by online_kernel. NOTE: These directories/files appear after physical memory hotplug phase. @@ -408,7 +418,6 @@ node if necessary. - allowing memory hot-add to ZONE_MOVABLE. maybe we need some switch like sysctl or new control file. - showing memory block and physical device relationship. - - showing memory block is under ZONE_MOVABLE or not - test and make it better memory offlining. - support HugeTLB page migration and offlining. - memmap removing at memory offline. |