The patch titled
Subject: mm, memory_hotplug: reorganize new pgdat initialization
has been added to the -mm tree. Its filename is
mm-memory_hotplug-reorganize-new-pgdat-initialization.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/mm-memory_hotplug-reorganize-new-pgdat-initialization.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/mm-memory_hotplug-reorganize-new-pgdat-initialization.patch
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------------------------------------------------------
From: Michal Hocko <mhocko@xxxxxxxx>
Subject: 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@xxxxxxxxxx
Signed-off-by: Michal Hocko <mhocko@xxxxxxxx>
Acked-by: Rafael Aquini <raquini@xxxxxxxxxx>
Acked-by: David Hildenbrand <david@xxxxxxxxxx>
Reviewed-by: Oscar Salvador <osalvador@xxxxxxx>
Cc: Alexey Makhalov <amakhalov@xxxxxxxxxx>
Cc: Christoph Lameter <cl@xxxxxxxxx>
Cc: Dennis Zhou <dennis@xxxxxxxxxx>
Cc: Eric Dumazet <eric.dumazet@xxxxxxxxx>
Cc: Mike Rapoport <rppt@xxxxxxxxxxxxx>
Cc: Nico Pache <npache@xxxxxxxxxx>
Cc: Tejun Heo <tj@xxxxxxxxxx>
Cc: Wei Yang <richard.weiyang@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/memory_hotplug.h | 2 +-
mm/memory_hotplug.c | 28 +++-------------------------
mm/page_alloc.c | 25 +++++++++++++++++++++++--
3 files changed, 27 insertions(+), 28 deletions(-)
--- a/include/linux/memory_hotplug.h~mm-memory_hotplug-reorganize-new-pgdat-initialization
+++ a/include/linux/memory_hotplug.h
@@ -319,7 +319,7 @@ extern void set_zone_contiguous(struct z
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,
--- a/mm/memory_hotplug.c~mm-memory_hotplug-reorganize-new-pgdat-initialization
+++ a/mm/memory_hotplug.c
@@ -1166,39 +1166,16 @@ static pg_data_t __ref *hotadd_init_pgda
{
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_pgda
* 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);
--- a/mm/page_alloc.c~mm-memory_hotplug-reorganize-new-pgdat-initialization
+++ a/mm/page_alloc.c
@@ -7551,12 +7551,33 @@ static void __meminit zone_init_internal
* 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);
}
_
Patches currently in -mm which might be from mhocko@xxxxxxxx are
mm-memory_hotplug-make-arch_alloc_nodedata-independent-on-config_memory_hotplug.patch
mm-handle-uninitialized-numa-nodes-gracefully.patch
mm-memory_hotplug-drop-arch_free_nodedata.patch
mm-memory_hotplug-reorganize-new-pgdat-initialization.patch
mm-make-free_area_init_node-aware-of-memory-less-nodes.patch
