[PATCH v2 3/5] mm, memory hotplug: small cleanup in online_pages()

From: Vlastimil Babka
Date: Mon Feb 08 2016 - 08:39:02 EST


We can reuse the nid we've determined instead of repeated pfn_to_nid() usages.
Also zone_to_nid() should be a bit cheaper in general than pfn_to_nid().

Signed-off-by: Vlastimil Babka <vbabka@xxxxxxx>
---
mm/memory_hotplug.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 7aa7697fedd1..66064008a489 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -1082,7 +1082,7 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages, int online_typ
arg.nr_pages = nr_pages;
node_states_check_changes_online(nr_pages, zone, &arg);

- nid = pfn_to_nid(pfn);
+ nid = zone_to_nid(zone);

ret = memory_notify(MEM_GOING_ONLINE, &arg);
ret = notifier_to_errno(ret);
@@ -1122,7 +1122,7 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages, int online_typ
pgdat_resize_unlock(zone->zone_pgdat, &flags);

if (onlined_pages) {
- node_states_set_node(zone_to_nid(zone), &arg);
+ node_states_set_node(nid, &arg);
if (need_zonelists_rebuild)
build_all_zonelists(NULL, NULL);
else
@@ -1134,7 +1134,7 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages, int online_typ
init_per_zone_wmark_min();

if (onlined_pages) {
- kswapd_run(zone_to_nid(zone));
+ kswapd_run(nid);
kcompactd_run(nid);
}

--
2.7.0