mm, memory-hotplug: dynamic configure movable memory and portion memory
Add online_movable and online_kernel for logic memory hotplug. This is
the dynamic version of "movablecore" & "kernelcore".
We have the same reason to introduce it as to introduce "movablecore" &
"kernelcore". It has the same motive as "movablecore" & "kernelcore", but
it is dynamic/running-time:
o We can configure memory as kernelcore or movablecore after boot.
Userspace workload is increased, we need more hugepage, we can't use
"online_movable" to add memory and allow the system use more
THP(transparent-huge-page), vice-verse when kernel workload is increase.
Also help for virtualization to dynamic configure host/guest's memory,
to save/(reduce waste) memory.
Memory capacity on Demand
o When a new node is physically online after boot, we need to use
"online_movable" or "online_kernel" to configure/portion it as we
expected when we logic-online it.
This configuration also helps for physically-memory-migrate.
o all benefit as the same as existed "movablecore" & "kernelcore".
o Preparing for movable-node, which is very important for power-saving,
hardware partitioning and high-available-system(hardware fault
management).
(Note, we don't introduce movable-node here.)
Action behavior:
When a memoryblock/memorysection is onlined by "online_movable", the kernel
will not have directly reference to the page of the memoryblock,
thus we can remove that memory any time when needed.
When it is online by "online_kernel", the kernel can use it.
When it is online by "online", the zone type doesn't changed.
Current constraints:
Only the memoryblock which is adjacent to the ZONE_MOVABLE
can be online from ZONE_NORMAL to ZONE_MOVABLE.
[akpm@linux-foundation.org: use min_t, cleanups]
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Jiang Liu <jiang.liu@huawei.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 571130e..5c1f495 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -214,6 +214,88 @@
zone_span_writeunlock(zone);
}
+static void resize_zone(struct zone *zone, unsigned long start_pfn,
+ unsigned long end_pfn)
+{
+ zone_span_writelock(zone);
+
+ zone->zone_start_pfn = start_pfn;
+ zone->spanned_pages = end_pfn - start_pfn;
+
+ zone_span_writeunlock(zone);
+}
+
+static void fix_zone_id(struct zone *zone, unsigned long start_pfn,
+ unsigned long end_pfn)
+{
+ enum zone_type zid = zone_idx(zone);
+ int nid = zone->zone_pgdat->node_id;
+ unsigned long pfn;
+
+ for (pfn = start_pfn; pfn < end_pfn; pfn++)
+ set_page_links(pfn_to_page(pfn), zid, nid, pfn);
+}
+
+static int move_pfn_range_left(struct zone *z1, struct zone *z2,
+ unsigned long start_pfn, unsigned long end_pfn)
+{
+ unsigned long flags;
+
+ pgdat_resize_lock(z1->zone_pgdat, &flags);
+
+ /* can't move pfns which are higher than @z2 */
+ if (end_pfn > z2->zone_start_pfn + z2->spanned_pages)
+ goto out_fail;
+ /* the move out part mast at the left most of @z2 */
+ if (start_pfn > z2->zone_start_pfn)
+ goto out_fail;
+ /* must included/overlap */
+ if (end_pfn <= z2->zone_start_pfn)
+ goto out_fail;
+
+ resize_zone(z1, z1->zone_start_pfn, end_pfn);
+ resize_zone(z2, end_pfn, z2->zone_start_pfn + z2->spanned_pages);
+
+ pgdat_resize_unlock(z1->zone_pgdat, &flags);
+
+ fix_zone_id(z1, start_pfn, end_pfn);
+
+ return 0;
+out_fail:
+ pgdat_resize_unlock(z1->zone_pgdat, &flags);
+ return -1;
+}
+
+static int move_pfn_range_right(struct zone *z1, struct zone *z2,
+ unsigned long start_pfn, unsigned long end_pfn)
+{
+ unsigned long flags;
+
+ pgdat_resize_lock(z1->zone_pgdat, &flags);
+
+ /* can't move pfns which are lower than @z1 */
+ if (z1->zone_start_pfn > start_pfn)
+ goto out_fail;
+ /* the move out part mast at the right most of @z1 */
+ if (z1->zone_start_pfn + z1->spanned_pages > end_pfn)
+ goto out_fail;
+ /* must included/overlap */
+ if (start_pfn >= z1->zone_start_pfn + z1->spanned_pages)
+ goto out_fail;
+
+ resize_zone(z1, z1->zone_start_pfn, start_pfn);
+ resize_zone(z2, start_pfn, z2->zone_start_pfn + z2->spanned_pages);
+
+ pgdat_resize_unlock(z1->zone_pgdat, &flags);
+
+ fix_zone_id(z2, start_pfn, end_pfn);
+
+ return 0;
+out_fail:
+ pgdat_resize_unlock(z1->zone_pgdat, &flags);
+ return -1;
+}
+
static void grow_pgdat_span(struct pglist_data *pgdat, unsigned long start_pfn,
unsigned long end_pfn)
{
@@ -508,7 +590,7 @@
}
-int __ref online_pages(unsigned long pfn, unsigned long nr_pages)
+int __ref online_pages(unsigned long pfn, unsigned long nr_pages, int online_type)
{
unsigned long onlined_pages = 0;
struct zone *zone;
@@ -525,6 +607,22 @@
*/
zone = page_zone(pfn_to_page(pfn));
+ if (online_type == ONLINE_KERNEL && zone_idx(zone) == ZONE_MOVABLE) {
+ if (move_pfn_range_left(zone - 1, zone, pfn, pfn + nr_pages)) {
+ unlock_memory_hotplug();
+ return -1;
+ }
+ }
+ if (online_type == ONLINE_MOVABLE && zone_idx(zone) == ZONE_MOVABLE - 1) {
+ if (move_pfn_range_right(zone, zone + 1, pfn, pfn + nr_pages)) {
+ unlock_memory_hotplug();
+ return -1;
+ }
+ }
+
+ /* Previous code may changed the zone of the pfn range */
+ zone = page_zone(pfn_to_page(pfn));
+
arg.start_pfn = pfn;
arg.nr_pages = nr_pages;
node_states_check_changes_online(nr_pages, zone, &arg);