linux/drivers/base
Michal Hocko c6f03e2903 mm, memory_hotplug: remove zone restrictions
Historically we have enforced that any kernel zone (e.g ZONE_NORMAL) has
to precede the Movable zone in the physical memory range.  The purpose
of the movable zone is, however, not bound to any physical memory
restriction.  It merely defines a class of migrateable and reclaimable
memory.

There are users (e.g.  CMA) who might want to reserve specific physical
memory ranges for their own purpose.  Moreover our pfn walkers have to
be prepared for zones overlapping in the physical range already because
we do support interleaving NUMA nodes and therefore zones can interleave
as well.  This means we can allow each memory block to be associated
with a different zone.

Loosen the current onlining semantic and allow explicit onlining type on
any memblock.  That means that online_{kernel,movable} will be allowed
regardless of the physical address of the memblock as long as it is
offline of course.  This might result in moveble zone overlapping with
other kernel zones.  Default onlining then becomes a bit tricky but
still sensible.  echo online > memoryXY/state will online the given
block to

	1) the default zone if the given range is outside of any zone
	2) the enclosing zone if such a zone doesn't interleave with
	   any other zone
        3) the default zone if more zones interleave for this range

where default zone is movable zone only if movable_node is enabled
otherwise it is a kernel zone.

Here is an example of the semantic with (movable_node is not present but
it work in an analogous way). We start with following memblocks, all of
them offline:

  memory34/valid_zones:Normal Movable
  memory35/valid_zones:Normal Movable
  memory36/valid_zones:Normal Movable
  memory37/valid_zones:Normal Movable
  memory38/valid_zones:Normal Movable
  memory39/valid_zones:Normal Movable
  memory40/valid_zones:Normal Movable
  memory41/valid_zones:Normal Movable

Now, we online block 34 in default mode and block 37 as movable

  root@test1:/sys/devices/system/node/node1# echo online > memory34/state
  root@test1:/sys/devices/system/node/node1# echo online_movable > memory37/state
  memory34/valid_zones:Normal
  memory35/valid_zones:Normal Movable
  memory36/valid_zones:Normal Movable
  memory37/valid_zones:Movable
  memory38/valid_zones:Normal Movable
  memory39/valid_zones:Normal Movable
  memory40/valid_zones:Normal Movable
  memory41/valid_zones:Normal Movable

As we can see all other blocks can still be onlined both into Normal and
Movable zones and the Normal is default because the Movable zone spans
only block37 now.

  root@test1:/sys/devices/system/node/node1# echo online_movable > memory41/state
  memory34/valid_zones:Normal
  memory35/valid_zones:Normal Movable
  memory36/valid_zones:Normal Movable
  memory37/valid_zones:Movable
  memory38/valid_zones:Movable Normal
  memory39/valid_zones:Movable Normal
  memory40/valid_zones:Movable Normal
  memory41/valid_zones:Movable

Now the default zone for blocks 37-41 has changed because movable zone
spans that range.

  root@test1:/sys/devices/system/node/node1# echo online_kernel > memory39/state
  memory34/valid_zones:Normal
  memory35/valid_zones:Normal Movable
  memory36/valid_zones:Normal Movable
  memory37/valid_zones:Movable
  memory38/valid_zones:Normal Movable
  memory39/valid_zones:Normal
  memory40/valid_zones:Movable Normal
  memory41/valid_zones:Movable

Note that the block 39 now belongs to the zone Normal and so block38
falls into Normal by default as well.

For completness

  root@test1:/sys/devices/system/node/node1# for i in memory[34]?
  do
	echo online > $i/state 2>/dev/null
  done

  memory34/valid_zones:Normal
  memory35/valid_zones:Normal
  memory36/valid_zones:Normal
  memory37/valid_zones:Movable
  memory38/valid_zones:Normal
  memory39/valid_zones:Normal
  memory40/valid_zones:Movable
  memory41/valid_zones:Movable

Implementation wise the change is quite straightforward.  We can get rid
of allow_online_pfn_range altogether.  online_pages allows only offline
nodes already.  The original default_zone_for_pfn will become
default_kernel_zone_for_pfn.  New default_zone_for_pfn implements the
above semantic.  zone_for_pfn_range is slightly reorganized to implement
kernel and movable online type explicitly and MMOP_ONLINE_KEEP becomes a
catch all default behavior.

Link: http://lkml.kernel.org/r/20170714121233.16861-3-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Reza Arbab <arbab@linux.vnet.ibm.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Yasuaki Ishimatsu <yasu.isimatu@gmail.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Kani Toshimitsu <toshi.kani@hpe.com>
Cc: <slaoub@gmail.com>
Cc: Daniel Kiper <daniel.kiper@oracle.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: <linux-api@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-06 17:27:25 -07:00
..
power Merge branch 'pm-sleep' 2017-09-04 00:06:02 +02:00
regmap regmap: regmap-w1: Fix build troubles 2017-07-17 15:53:00 +01:00
test driver core: test_async: fix up typo found by 0-day 2016-11-29 22:06:42 +01:00
arch_topology.c base: Convert to using %pOF instead of full_name 2017-08-28 17:47:55 +02:00
attribute_container.c attribute_container: Fix typo 2016-08-31 15:13:56 +02:00
base.h driver core: make device_{add|remove}_groups() public 2017-07-22 11:59:23 +02:00
bus.c driver core: bus: Fix a potential double free 2017-08-31 18:57:30 +02:00
cacheinfo.c Merge branch 'x86-cache-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-12-22 09:25:45 -08:00
class.c driver core: remove class_attrs from struct class 2017-06-09 10:41:00 +02:00
component.c Merge 4.5-rc4 into driver-core-next 2016-02-14 14:29:55 -08:00
container.c
core.c Do not disable driver and bus shutdown hook when class shutdown hook is set. 2017-08-28 18:02:46 +02:00
cpu.c CPU / PM: expose pm_qos_resume_latency for CPUs 2017-01-30 11:05:29 +01:00
dd.c initcall_debug: add deferred probe times 2017-08-03 17:48:49 -07:00
devcoredump.c driver core: devcoredump: convert to use class_groups 2016-11-29 21:12:12 +01:00
devres.c devres: add devm_alloc_percpu() 2016-11-15 22:34:25 -05:00
devtmpfs.c statx: Add a system call to make enhanced file info available 2017-03-02 20:51:15 -05:00
dma-coherent.c dma-coherent: introduce interface for default DMA pool 2017-07-20 16:09:10 +02:00
dma-contiguous.c cma: Store a name in the cma structure 2017-04-18 20:41:12 +02:00
dma-mapping.c dma-coherent: introduce interface for default DMA pool 2017-07-20 16:09:10 +02:00
driver.c driver core: add missing blank line after declaration 2015-03-25 14:36:30 +01:00
firmware_class.c Merge 4.13-rc5 into driver-core-next 2017-08-14 13:33:39 -07:00
firmware.c
hypervisor.c
init.c drivers: of/base: move of_init to driver_init 2015-05-26 19:55:56 -07:00
isa.c isa: Call isa_bus_init before dependent ISA bus drivers register 2016-06-17 20:47:11 -07:00
Kconfig arm, arm64: factorize common cpu capacity default code 2017-06-03 19:10:09 +09:00
Makefile arm, arm64: factorize common cpu capacity default code 2017-06-03 19:10:09 +09:00
map.c
memory.c mm, memory_hotplug: remove zone restrictions 2017-09-06 17:27:25 -07:00
module.c base: make module_create_drivers_dir race-free 2016-06-15 19:21:31 -07:00
node.c mm: drop useless local parameters of __register_one_node() 2017-07-10 16:32:32 -07:00
pinctrl.c driver core: fix automatic pinctrl management 2017-06-13 11:07:32 +02:00
platform-msi.c irqchip/MSI: Use irq_domain_update_bus_token instead of an open coded access 2017-06-22 18:29:17 +02:00
platform.c This is the bulk of GPIO changes for the v4.13 series: 2017-07-07 12:40:27 -07:00
property.c device property: Introduce fwnode_property_get_reference_args 2017-07-22 00:04:51 +02:00
soc.c base: soc: Allow early registration of a single SoC device 2017-03-29 21:43:26 +02:00
syscore.c
topology.c base: topology: constify attribute_group structures. 2017-08-28 17:49:22 +02:00
transport_class.c