The patch titled
     Subject: mem-hotplug: reset node present pages when hot-adding a new pgdat
has been removed from the -mm tree.  Its filename was
     mem-hotplug-reset-node-present-pages-when-hot-adding-a-new-pgdat.patch

This patch was dropped because it was merged into mainline or a subsystem tree

------------------------------------------------------
From: Tang Chen <[email protected]>
Subject: mem-hotplug: reset node present pages when hot-adding a new 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().  Otherwise, /proc/zoneinfo will corrupt:

When the memory of node2 is offline:
# cat /proc/zoneinfo
......
Node 2, zone   Movable
......
        spanned  8388608
        present  8388608
        managed  0

When we online memory on node2:
# cat /proc/zoneinfo
......
Node 2, zone   Movable
......
        spanned  8388608
        present  16777216
        managed  8388608

Signed-off-by: Tang Chen <[email protected]>
Reviewed-by: Yasuaki Ishimatsu <[email protected]>
Cc: <[email protected]>    [3.16+]
Signed-off-by: Andrew Morton <[email protected]>
---

 mm/memory_hotplug.c |   17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff -puN 
mm/memory_hotplug.c~mem-hotplug-reset-node-present-pages-when-hot-adding-a-new-pgdat
 mm/memory_hotplug.c
--- 
a/mm/memory_hotplug.c~mem-hotplug-reset-node-present-pages-when-hot-adding-a-new-pgdat
+++ a/mm/memory_hotplug.c
@@ -1067,6 +1067,16 @@ out:
 }
 #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
 
+static void reset_node_present_pages(pg_data_t *pgdat)
+{
+       struct zone *z;
+
+       for (z = pgdat->node_zones; z < pgdat->node_zones + MAX_NR_ZONES; z++)
+               z->present_pages = 0;
+
+       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)
 {
@@ -1105,6 +1115,13 @@ static pg_data_t __ref *hotadd_new_pgdat
         */
        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;
 }
 
_

Patches currently in -mm which might be from [email protected] are

memblock-refactor-functions-to-set-clear-memblock_hotplug.patch

--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to