Commit c6123a19 authored by Aneesh Kumar K.V's avatar Aneesh Kumar K.V Committed by Andrew Morton
Browse files

mm/demotion: add hotplug callbacks to handle new numa node onlined 

If the new NUMA node onlined doesn't have a abstract distance assigned,
the kernel adds the NUMA node to default memory tier.

[aneesh.kumar@linux.ibm.com: fix kernel error with memory hotplug]
  Link: https://lkml.kernel.org/r/20220825092019.379069-1-aneesh.kumar@linux.ibm.com
Link: https://lkml.kernel.org/r/20220818131042.113280-4-aneesh.kumar@linux.ibm.com


Signed-off-by: default avatarAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reviewed-by: default avatar"Huang, Ying" <ying.huang@intel.com>
Acked-by: default avatarWei Xu <weixugc@google.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Bharata B Rao <bharata@amd.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Hesham Almatary <hesham.almatary@huawei.com>
Cc: Jagdish Gediya <jvgediya.oss@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Tim Chen <tim.c.chen@intel.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: SeongJae Park <sj@kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 91952440

include/linux/memory-tiers.h

+1 −0
Original line number Diff line number Diff line
@@ -14,6 +14,7 @@ 
 * the same memory tier.

 */

#define MEMTIER_ADISTANCE_DRAM	((4 * MEMTIER_CHUNK_SIZE) + (MEMTIER_CHUNK_SIZE >> 1))

#define MEMTIER_HOTPLUG_PRIO	100



#ifdef CONFIG_NUMA

#include <linux/types.h>

mm/memory-tiers.c

+68 −0
Original line number Diff line number Diff line
@@ -5,6 +5,7 @@ 
#include <linux/lockdep.h>

#include <linux/sysfs.h>

#include <linux/kobject.h>

#include <linux/memory.h>

#include <linux/memory-tiers.h>



struct memory_tier {
@@ -105,6 +106,72 @@ static struct memory_tier *set_node_memory_tier(int node) 
	return memtier;

}



static struct memory_tier *__node_get_memory_tier(int node)

{

	struct memory_dev_type *memtype;



	memtype = node_memory_types[node];

	if (memtype && node_isset(node, memtype->nodes))

		return memtype->memtier;

	return NULL;

}



static void destroy_memory_tier(struct memory_tier *memtier)

{

	list_del(&memtier->list);

	kfree(memtier);

}



static bool clear_node_memory_tier(int node)

{

	bool cleared = false;

	struct memory_tier *memtier;



	memtier = __node_get_memory_tier(node);

	if (memtier) {

		struct memory_dev_type *memtype;



		memtype = node_memory_types[node];

		node_clear(node, memtype->nodes);

		if (nodes_empty(memtype->nodes)) {

			list_del_init(&memtype->tier_sibiling);

			memtype->memtier = NULL;

			if (list_empty(&memtier->memory_types))

				destroy_memory_tier(memtier);

		}

		cleared = true;

	}

	return cleared;

}



static int __meminit memtier_hotplug_callback(struct notifier_block *self,

					      unsigned long action, void *_arg)

{

	struct memory_notify *arg = _arg;



	/*

	 * Only update the node migration order when a node is

	 * changing status, like online->offline.

	 */

	if (arg->status_change_nid < 0)

		return notifier_from_errno(0);



	switch (action) {

	case MEM_OFFLINE:

		mutex_lock(&memory_tier_lock);

		clear_node_memory_tier(arg->status_change_nid);

		mutex_unlock(&memory_tier_lock);

		break;

	case MEM_ONLINE:

		mutex_lock(&memory_tier_lock);

		set_node_memory_tier(arg->status_change_nid);

		mutex_unlock(&memory_tier_lock);

		break;

	}



	return notifier_from_errno(0);

}



static int __init memory_tier_init(void)

{

	int node;
@@ -126,6 +193,7 @@ static int __init memory_tier_init(void) 
	}

	mutex_unlock(&memory_tier_lock);



	hotplug_memory_notifier(memtier_hotplug_callback, MEMTIER_HOTPLUG_PRIO);

	return 0;

}

subsys_initcall(memory_tier_init);