diff options
| author | Wei Yang <weiyang@linux.vnet.ibm.com> | 2015-09-08 14:59:48 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-09-08 15:35:28 -0700 |
| commit | 904a9553d4fcdc0c7d5621f6178f0e07598701dc (patch) | |
| tree | 2dd0acd4856e1365c3abb47ff7da700200e29279 | |
| parent | 52a2b53ffde6d6018dfc454fbde34383351fb896 (diff) | |
| download | x86-pkeys-904a9553d4fcdc0c7d5621f6178f0e07598701dc.tar.gz | |
mm/page_alloc.c: refine the calculation of highest possible node id
nr_node_ids records the highest possible node id, which is calculated by
scanning the bitmap node_states[N_POSSIBLE]. Current implementation
scan the bitmap from the beginning, which will scan the whole bitmap.
This patch reverses the order by scanning from the end with
find_last_bit().
Signed-off-by: Wei Yang <weiyang@linux.vnet.ibm.com>
Cc: Tejun Heo <tj@kernel.org>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | mm/page_alloc.c | 6 |
1 files changed, 2 insertions, 4 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 5b5240b7f642de..809e27e77b3a39 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -5478,11 +5478,9 @@ void __paginginit free_area_init_node(int nid, unsigned long *zones_size, */ void __init setup_nr_node_ids(void) { - unsigned int node; - unsigned int highest = 0; + unsigned int highest; - for_each_node_mask(node, node_possible_map) - highest = node; + highest = find_last_bit(node_possible_map.bits, MAX_NUMNODES); nr_node_ids = highest + 1; } #endif |