mm, memory_hotplug: reorganize new pgdat initialization

When a !node_online node is brought up it needs a hotplug specific
initialization because the node could be either uninitialized yet or it
could have been recycled after previous hotremove.  hotadd_init_pgdat is
responsible for that.

Internal pgdat state is initialized at two places currently
	- hotadd_init_pgdat
	- free_area_init_core_hotplug

There is no real clear cut what should go where but this patch's chosen to
move the whole internal state initialization into
free_area_init_core_hotplug.  hotadd_init_pgdat is still responsible to
pull all the parts together - most notably to initialize zonelists because
those depend on the overall topology.

This patch doesn't introduce any functional change.

Link: https://lkml.kernel.org/r/20220127085305.20890-5-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Rafael Aquini <raquini@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Alexey Makhalov <amakhalov@vmware.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Nico Pache <npache@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Michal Hocko 2022-03-22 14:47:00 -07:00 committed by Linus Torvalds
parent 390511e147
commit 70b5b46a75
3 changed files with 27 additions and 28 deletions

View file

@ -319,7 +319,7 @@ extern void set_zone_contiguous(struct zone *zone);
extern void clear_zone_contiguous(struct zone *zone);
#ifdef CONFIG_MEMORY_HOTPLUG
extern void __ref free_area_init_core_hotplug(int nid);
extern void __ref free_area_init_core_hotplug(struct pglist_data *pgdat);
extern int __add_memory(int nid, u64 start, u64 size, mhp_t mhp_flags);
extern int add_memory(int nid, u64 start, u64 size, mhp_t mhp_flags);
extern int add_memory_resource(int nid, struct resource *resource,

View file

@ -1166,39 +1166,16 @@ static pg_data_t __ref *hotadd_init_pgdat(int nid)
{
struct pglist_data *pgdat;
pgdat = NODE_DATA(nid);
/*
* NODE_DATA is preallocated (free_area_init) but its internal
* state is not allocated completely. Add missing pieces.
* Completely offline nodes stay around and they just need
* reintialization.
*/
if (pgdat->per_cpu_nodestats == &boot_nodestats) {
pgdat->per_cpu_nodestats =
alloc_percpu(struct per_cpu_nodestat);
} else {
int cpu;
/*
* Reset the nr_zones, order and highest_zoneidx before reuse.
* Note that kswapd will init kswapd_highest_zoneidx properly
* when it starts in the near future.
*/
pgdat->nr_zones = 0;
pgdat->kswapd_order = 0;
pgdat->kswapd_highest_zoneidx = 0;
for_each_online_cpu(cpu) {
struct per_cpu_nodestat *p;
p = per_cpu_ptr(pgdat->per_cpu_nodestats, cpu);
memset(p, 0, sizeof(*p));
}
}
pgdat->node_start_pfn = 0;
pgdat = NODE_DATA(nid);
/* init node's zones as empty zones, we don't have any present pages.*/
free_area_init_core_hotplug(nid);
free_area_init_core_hotplug(pgdat);
/*
* The node we allocated has no zone fallback lists. For avoiding
@ -1210,6 +1187,7 @@ static pg_data_t __ref *hotadd_init_pgdat(int nid)
* When memory is hot-added, all the memory is in offline state. So
* clear all zones' present_pages because they will be updated in
* online_pages() and offline_pages().
* TODO: should be in free_area_init_core_hotplug?
*/
reset_node_managed_pages(pgdat);
reset_node_present_pages(pgdat);

View file

@ -7466,12 +7466,33 @@ static void __meminit zone_init_internals(struct zone *zone, enum zone_type idx,
* NOTE: this function is only called during memory hotplug
*/
#ifdef CONFIG_MEMORY_HOTPLUG
void __ref free_area_init_core_hotplug(int nid)
void __ref free_area_init_core_hotplug(struct pglist_data *pgdat)
{
int nid = pgdat->node_id;
enum zone_type z;
pg_data_t *pgdat = NODE_DATA(nid);
int cpu;
pgdat_init_internals(pgdat);
if (pgdat->per_cpu_nodestats == &boot_nodestats)
pgdat->per_cpu_nodestats = alloc_percpu(struct per_cpu_nodestat);
/*
* Reset the nr_zones, order and highest_zoneidx before reuse.
* Note that kswapd will init kswapd_highest_zoneidx properly
* when it starts in the near future.
*/
pgdat->nr_zones = 0;
pgdat->kswapd_order = 0;
pgdat->kswapd_highest_zoneidx = 0;
pgdat->node_start_pfn = 0;
for_each_online_cpu(cpu) {
struct per_cpu_nodestat *p;
p = per_cpu_ptr(pgdat->per_cpu_nodestats, cpu);
memset(p, 0, sizeof(*p));
}
for (z = 0; z < MAX_NR_ZONES; z++)
zone_init_internals(&pgdat->node_zones[z], z, nid, 0);
}