--- v7
+++ v8
@@ -1,7 +1,9 @@
-From: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
+From: Wen Congyang <wency@cn.fujitsu.com>
-The patch adds node_set_offline() and unregister_one_node() to remove_memory()
-for removing sysfs file of node.
+This patch introduces a new function try_offline_node() to
+remove sysfs file of node when all memory sections of this
+node are removed. If some memory sections of this node are
+not removed, this function does nothing.
CC: David Rientjes <rientjes@google.com>
CC: Jiang Liu <liuj97@gmail.com>
@@ -12,27 +14,62 @@
Cc: Minchan Kim <minchan.kim@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
-CC: Wen Congyang <wency@cn.fujitsu.com>
-Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
+CC: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
+Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
---
- mm/memory_hotplug.c | 5 +++++
- 1 files changed, 5 insertions(+), 0 deletions(-)
+ mm/memory_hotplug.c | 33 +++++++++++++++++++++++++++++++++
+ 1 files changed, 33 insertions(+), 0 deletions(-)
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
-index 00c050f..e5928c7 100644
+index 493298f..fb8af64 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
-@@ -1279,6 +1279,11 @@ int __ref remove_memory(int nid, u64 start, u64 size)
- /* remove memmap entry */
+@@ -1286,6 +1286,37 @@ int offline_memory(u64 start, u64 size)
+ return 0;
+ }
+
++/* offline the node if all memory sections of this node are removed */
++static void try_offline_node(int nid)
++{
++ unsigned long start_pfn = NODE_DATA(nid)->node_start_pfn;
++ unsigned long end_pfn = start_pfn + NODE_DATA(nid)->node_spanned_pages;
++ unsigned long pfn;
++
++ for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
++ unsigned long section_nr = pfn_to_section_nr(pfn);
++
++ if (!present_section_nr(section_nr))
++ continue;
++
++ if (pfn_to_nid(pfn) != nid)
++ continue;
++
++ /*
++ * some memory sections of this node are not removed, and we
++ * can't offline node now.
++ */
++ return;
++ }
++
++ /*
++ * all memory sections of this node are removed, we can offline this
++ * node now.
++ */
++ node_set_offline(nid);
++ unregister_one_node(nid);
++}
++
+ int __ref remove_memory(int nid, u64 start, u64 size)
+ {
+ int ret = 0;
+@@ -1306,6 +1337,8 @@ int __ref remove_memory(int nid, u64 start, u64 size)
firmware_map_remove(start, start + size, "System RAM");
-+ if (!node_present_pages(nid)) {
-+ node_set_offline(nid);
-+ unregister_one_node(nid);
-+ }
+ arch_remove_memory(start, size);
+
- arch_remove_memory(start, size);
++ try_offline_node(nid);
out:
unlock_memory_hotplug();
+ return ret;
--
1.7.1