In memory hotplug situation, the hotpluggable memory should be
arranged in ZONE_MOVABLE because memory in ZONE_NORMAL may be
used by kernel, and Linux cannot migrate pages used by kernel.
So we need a way to specify hotpluggable memory as movable. It
should be as easy as possible.
According to ACPI spec 5.0, SRAT table has memory affinity
structure and the structure has Hot Pluggable Filed.
See "5.2.16.2 Memory Affinity Structure".
If we use the information, we might be able to specify hotpluggable
memory by firmware. For example, if Hot Pluggable Filed is enabled,
kernel sets the memory as movable memory.
To achieve this goal, we need to do the following:
1. Prevent memblock from allocating hotpluggable memroy for kernel.
This is done by reserving hotpluggable memory in memblock as the
folowing steps:
1) Parse SRAT early enough so that memblock knows which memory
is hotpluggable.
2) Add a "flags" member to memblock so that it is able to tell
which memory is hotpluggable when freeing it to buddy.
2. Free hotpluggable memory to buddy system when memory initialization
is done.
3. Arrange hotpluggable memory in ZONE_MOVABLE.
(This will cause NUMA performance decreased)
4. Provide a user interface to enable/disable this functionality.
(This is useful for those who don't use memory hotplug and who don't
want to lose their NUMA performance.)
This patch-set does the following:
patch1: Fix a little problem.
patch2: Have Hot-Pluggable Field in SRAT printed when parsing SRAT.
patch4,5: Introduce hotpluggable field to numa_meminfo.
patch6,7: Introduce flags to memblock, and keep the public APIs prototype
unmodified.
patch8: Reserve node-life-cycle memory as MEMBLK_LOCAL_NODE with memblock.
patch9,10: Reserve hotpluggable memory as MEMBLK_HOTPLUGGABLE with memblock,
and free it to buddy when memory initialization is done.
patch3,11,12: Improve "movablecore" boot option to support "movablecore=acpi".
This patch-set is based on Yinghai's
"x86, ACPI, numa: Parse numa info early" patch-set.
Please refer to:
v1: https://lkml.org/lkml/2013/3/7/642
v2: https://lkml.org/lkml/2013/3/10/47
v3: https://lkml.org/lkml/2013/4/4/639
v4: https://lkml.org/lkml/2013/4/11/829
And Yinghai's patch did the following things:
1) Parse SRAT early enough.
2）Allocate pagetable pages in local node.
Tang Chen (11):
acpi: Print Hot-Pluggable Field in SRAT.
page_alloc, mem-hotplug: Improve movablecore to {en|dis}able using
SRAT.
x86, numa, acpi, memory-hotplug: Introduce hotplug info into struct
numa_meminfo.
x86, numa, acpi, memory-hotplug: Consider hotplug info when cleanup
numa_meminfo.
memblock, numa: Introduce flag into memblock.
x86, numa, mem-hotplug: Mark nodes which the kernel resides in.
x86, numa, memblock: Introduce MEMBLK_LOCAL_NODE to mark and reserve
node-life-cycle data.
x86, acpi, numa, mem-hotplug: Introduce MEMBLK_HOTPLUGGABLE to mark
and reserve hotpluggable memory.
x86, memblock, mem-hotplug: Free hotpluggable memory reserved by
memblock.
x86, numa, acpi, memory-hotplug: Make movablecore=acpi have higher
priority.
doc, page_alloc, acpi, mem-hotplug: Add doc for movablecore=acpi boot
option.
Yasuaki Ishimatsu (1):
x86: get pg_data_t's memory from other node
Documentation/kernel-parameters.txt | 8 ++
arch/x86/include/asm/numa.h | 3 +-
arch/x86/kernel/apic/numaq_32.c | 2 +-
arch/x86/mm/amdtopology.c | 3 +-
arch/x86/mm/init.c | 16 +++-
arch/x86/mm/numa.c | 60 ++++++++++++++---
arch/x86/mm/numa_internal.h | 1 +
arch/x86/mm/srat.c | 11 ++-
include/linux/memblock.h | 16 +++++
include/linux/memory_hotplug.h | 3 +
mm/memblock.c | 127 ++++++++++++++++++++++++++++++----
mm/nobootmem.c | 3 +
mm/page_alloc.c | 37 ++++++++++-
13 files changed, 253 insertions(+), 37 deletions(-)
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