mem-hotplug: reset node managed pages when hot-adding a new pgdat
In free_area_init_core(), zone->managed_pages is set to an approximate
value for lowmem, and will be adjusted when the bootmem allocator frees
pages into the buddy system.
But free_area_init_core() is also called by hotadd_new_pgdat() when
hot-adding memory. As a result, zone->managed_pages of the newly added
node's pgdat is set to an approximate value in the very beginning.
Even if the memory on that node has node been onlined,
/sys/device/system/node/nodeXXX/meminfo has wrong value:
hot-add node2 (memory not onlined)
cat /sys/device/system/node/node2/meminfo
Node 2 MemTotal: 33554432 kB
Node 2 MemFree: 0 kB
Node 2 MemUsed: 33554432 kB
Node 2 Active: 0 kB
This patch fixes this problem by reset node managed pages to 0 after
hot-adding a new node.
1. Move reset_managed_pages_done from reset_node_managed_pages() to
reset_all_zones_managed_pages()
2. Make reset_node_managed_pages() non-static
3. Call reset_node_managed_pages() in hotadd_new_pgdat() after pgdat
is initialized
Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: <stable@vger.kernel.org> [3.16+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/nobootmem.c b/mm/nobootmem.c
index 7c7ab32..90b5046 100644
--- a/mm/nobootmem.c
+++ b/mm/nobootmem.c
@@ -145,12 +145,10 @@
static int reset_managed_pages_done __initdata;
-static inline void __init reset_node_managed_pages(pg_data_t *pgdat)
+void reset_node_managed_pages(pg_data_t *pgdat)
{
struct zone *z;
- if (reset_managed_pages_done)
- return;
for (z = pgdat->node_zones; z < pgdat->node_zones + MAX_NR_ZONES; z++)
z->managed_pages = 0;
}
@@ -159,8 +157,12 @@
{
struct pglist_data *pgdat;
+ if (reset_managed_pages_done)
+ return;
+
for_each_online_pgdat(pgdat)
reset_node_managed_pages(pgdat);
+
reset_managed_pages_done = 1;
}