From: Oscar Salvador <osalvador@xxxxxxx>
Currently, we call free_area_init_node() from the memhotplug path.
In there, we set some pgdat's fields, and call calculate_node_totalpages().
calculate_node_totalpages() calculates the # of pages the node has.
Since the node is either new, or we are re-using it, the zones belonging to
this node should not have any pages, so there is no point to calculate this now.
Actually, we set the values to 0 later on with the calls to:
reset_node_managed_pages()
reset_node_present_pages()
The # of pages per zone and the # of pages per zone will be calculated later on
when onlining the pages:
online_pages()->move_pfn_range()->move_pfn_range_to_zone()->resize_zone_range()
online_pages()->move_pfn_range()->move_pfn_range_to_zone()->resize_pgdat_range()
This introduces the memhotplug version of free_area_init_core and makes
hotadd_new_pgdat use it.
This function will only be called from memhotplug path:
hotadd_new_pgdat()->free_area_init_core_hotplug().
free_area_init_core_hotplug() performs only a subset of the actions that
free_area_init_core_hotplug() does.
Signed-off-by: Oscar Salvador <osalvador@xxxxxxx>
---
include/linux/mm.h | 1 +
mm/memory_hotplug.c | 23 +++++++++--------------
mm/page_alloc.c | 19 +++++++++++++++++++
3 files changed, 29 insertions(+), 14 deletions(-)
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 6954ad183159..20430becd908 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2001,6 +2001,7 @@ extern void free_area_init(unsigned long * zones_size);
extern void free_area_init_node(int nid, unsigned long * zones_size,
unsigned long zone_start_pfn, unsigned long *zholes_size);
extern void free_initmem(void);
+extern void free_area_init_core_hotplug(int nid);
/*
* Free reserved pages within range [PAGE_ALIGN(start), end & PAGE_MASK)
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 4eb6e824a80c..bef8a3f7a760 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -978,12 +978,11 @@ static void reset_node_present_pages(pg_data_t *pgdat)
pgdat->node_present_pages = 0;
}
+
/* we are OK calling __meminit stuff here - we have CONFIG_MEMORY_HOTPLUG */
static pg_data_t __ref *hotadd_new_pgdat(int nid, u64 start)
{
struct pglist_data *pgdat;
- unsigned long zones_size[MAX_NR_ZONES] = {0};
- unsigned long zholes_size[MAX_NR_ZONES] = {0};
unsigned long start_pfn = PFN_DOWN(start);
pgdat = NODE_DATA(nid);
@@ -1006,8 +1005,11 @@ static pg_data_t __ref *hotadd_new_pgdat(int nid, u64 start)
/* we can use NODE_DATA(nid) from here */
+ pgdat->node_id = nid;
+ pgdat->node_start_pfn = start_pfn;
+
/* init node's zones as empty zones, we don't have any present pages.*/
- free_area_init_node(nid, zones_size, start_pfn, zholes_size);
+ free_area_init_core_hotplug(nid);
pgdat->per_cpu_nodestats = alloc_percpu(struct per_cpu_nodestat);
/*
@@ -1017,18 +1019,11 @@ static pg_data_t __ref *hotadd_new_pgdat(int nid, u64 start)
build_all_zonelists(pgdat);
/*
- * zone->managed_pages is set to an approximate value in
- * free_area_init_core(), which will cause
- * /sys/device/system/node/nodeX/meminfo has wrong data.
- * So reset it to 0 before any memory is onlined.
- */
+ * 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().
+ */
reset_node_managed_pages(pgdat);
-
- /*
- * 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().
- */
reset_node_present_pages(pgdat);
return pgdat;
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index a455dc85da19..a36b4db26b50 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -6265,6 +6265,25 @@ static void zone_init_internals(struct zone *zone, enum zone_type idx, int nid,
}
/*
+ * Set up the zone data structures
+ * - init pgdat internals
+ * - init all zones belonging to this node
+ *
+ * NOTE: this function is only called during memory hotplug
+ */
+void __paginginit free_area_init_core_hotplug(int nid)
+{
+ enum zone_type j;
+ pg_data_t *pgdat = NODE_DATA(nid);
+
+ pgdat_init_internals(pgdat);
+ for(j = 0; j < MAX_NR_ZONES; j++) {
+ struct zone *zone = pgdat->node_zones + j;
+ zone_init_internals(zone, j, nid, 0);
+ }
+}
+
+/*
* Set up the zone data structures:
* - mark all pages reserved
* - mark all memory queues empty
--
2.13.6
