[PATCH v2 2/3] powerpc/mm: allow memory hotplug into a memoryless node

From: Reza Arbab
Date: Wed Sep 14 2016 - 16:07:21 EST


Remove the check which prevents us from hotplugging into an empty node.

This limitation has been questioned before [1], and judging by the
response, there doesn't seem to be a reason we can't remove it. No issues
have been found in light testing.

[1] http://lkml.kernel.org/r/CAGZKiBrmkSa1yyhbf5hwGxubcjsE5SmkSMY4tpANERMe2UG4bg@xxxxxxxxxxxxxx
http://lkml.kernel.org/r/20160511215051.GF22115@xxxxxxxxxxxxxxxxxxxxxxxxxxx

Signed-off-by: Reza Arbab <arbab@xxxxxxxxxxxxxxxxxx>
Acked-by: Balbir Singh <bsingharora@xxxxxxxxx>
Cc: Nathan Fontenot <nfont@xxxxxxxxxxxxxxxxxx>
Cc: Bharata B Rao <bharata@xxxxxxxxxxxxxxxxxx>
---
arch/powerpc/mm/numa.c | 13 +------------
1 file changed, 1 insertion(+), 12 deletions(-)

diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index 75b9cd6..d7ac419 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -1121,7 +1121,7 @@ static int hot_add_node_scn_to_nid(unsigned long scn_addr)
int hot_add_scn_to_nid(unsigned long scn_addr)
{
struct device_node *memory = NULL;
- int nid, found = 0;
+ int nid;

if (!numa_enabled || (min_common_depth < 0))
return first_online_node;
@@ -1137,17 +1137,6 @@ int hot_add_scn_to_nid(unsigned long scn_addr)
if (nid < 0 || !node_online(nid))
nid = first_online_node;

- if (NODE_DATA(nid)->node_spanned_pages)
- return nid;
-
- for_each_online_node(nid) {
- if (NODE_DATA(nid)->node_spanned_pages) {
- found = 1;
- break;
- }
- }
-
- BUG_ON(!found);
return nid;
}

--
1.8.3.1