From: Oscar Salvador <osalvador@xxxxxxx>
When hotpluging memory, it is possible that two calls are being made
to register_mem_sect_under_node().
One comes from __add_section()->hotplug_memory_register()
and the other from add_memory_resource()->link_mem_sections() if
we had to register a new node.
In case we had to register a new node, hotplug_memory_register()
will only handle/allocate the memory_block's since
register_mem_sect_under_node() will return right away because the
node it is not online yet.
I think it is better if we leave hotplug_memory_register() to
handle/allocate only memory_block's and make link_mem_sections()
to call register_mem_sect_under_node().
So this patch removes the call to register_mem_sect_under_node()
from hotplug_memory_register(), and moves the call to link_mem_sections()
out of the condition, so it will always be called.
In this way we only have one place where the memory sections
are registered.
Signed-off-by: Oscar Salvador <osalvador@xxxxxxx>
---
drivers/base/memory.c | 2 --
mm/memory_hotplug.c | 40 ++++++++++++++++++----------------------
2 files changed, 18 insertions(+), 24 deletions(-)
diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index f5e560188a18..c8a1cb0b6136 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -736,8 +736,6 @@ int hotplug_memory_register(int nid, struct mem_section *section)
mem->section_count++;
}
- if (mem->section_count == sections_per_block)
- ret = register_mem_sect_under_node(mem, nid, false);
out:
mutex_unlock(&mem_sysfs_mutex);
return ret;
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 29a5fc89bdb1..f84ef96175ab 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -1118,6 +1118,7 @@ int __ref add_memory_resource(int nid, struct resource *res, bool online)
u64 start, size;
bool new_node;
int ret;
+ unsigned long start_pfn, nr_pages;
start = res->start;
size = resource_size(res);
@@ -1147,34 +1148,21 @@ int __ref add_memory_resource(int nid, struct resource *res, bool online)
if (ret < 0)
goto error;
- /* we online node here. we can't roll back from here. */
- node_set_online(nid);
-
if (new_node) {
- unsigned long start_pfn = start >> PAGE_SHIFT;
- unsigned long nr_pages = size >> PAGE_SHIFT;
-
+ /* we online node here. we can't roll back from here. */
+ node_set_online(nid);
ret = __register_one_node(nid);
if (ret)
goto register_fail;
-
- /*
- * link memory sections under this node. This is already
- * done when creatig memory section in register_new_memory
- * but that depends to have the node registered so offline
- * nodes have to go through register_node.
- * TODO clean up this mess.
- */
- ret = link_mem_sections(nid, start_pfn, nr_pages, false);
-register_fail:
- /*
- * If sysfs file of new node can't create, cpu on the node
- * can't be hot-added. There is no rollback way now.
- * So, check by BUG_ON() to catch it reluctantly..
- */
- BUG_ON(ret);
}
+ /* link memory sections under this node.*/
+ start_pfn = start >> PAGE_SHIFT;
+ nr_pages = size >> PAGE_SHIFT;
+ ret = link_mem_sections(nid, start_pfn, nr_pages, false);
+ if (ret)
+ goto register_fail;
+
/* create new memmap entry */
firmware_map_add_hotplug(start, start + size, "System RAM");
@@ -1185,6 +1173,14 @@ int __ref add_memory_resource(int nid, struct resource *res, bool online)
goto out;
+register_fail:
+ /*
+ * If sysfs file of new node can't create, cpu on the node
+ * can't be hot-added. There is no rollback way now.
+ * So, check by BUG_ON() to catch it reluctantly..
+ */
+ BUG_ON(ret);
+
error:
/* rollback pgdat allocation and others */
if (new_node)
--
2.13.6
