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Diffstat (limited to 'mm/mempolicy.c')
-rw-r--r--mm/mempolicy.c33
1 files changed, 31 insertions, 2 deletions
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index b4a039d779b0..48ba9729062e 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -127,6 +127,32 @@ static struct mempolicy default_policy = {
static struct mempolicy preferred_node_policy[MAX_NUMNODES];
+/**
+ * numa_map_to_online_node - Find closest online node
+ * @nid: Node id to start the search
+ *
+ * Lookup the next closest node by distance if @nid is not online.
+ */
+int numa_map_to_online_node(int node)
+{
+ int min_dist = INT_MAX, dist, n, min_node;
+
+ if (node == NUMA_NO_NODE || node_online(node))
+ return node;
+
+ min_node = node;
+ for_each_online_node(n) {
+ dist = node_distance(node, n);
+ if (dist < min_dist) {
+ min_dist = dist;
+ min_node = n;
+ }
+ }
+
+ return min_node;
+}
+EXPORT_SYMBOL_GPL(numa_map_to_online_node);
+
struct mempolicy *get_task_policy(struct task_struct *p)
{
struct mempolicy *pol = p->mempolicy;
@@ -896,12 +922,15 @@ static void get_policy_nodemask(struct mempolicy *p, nodemask_t *nodes)
static int lookup_node(struct mm_struct *mm, unsigned long addr)
{
- struct page *p;
+ struct page *p = NULL;
int err;
int locked = 1;
err = get_user_pages_locked(addr & PAGE_MASK, 1, 0, &p, &locked);
- if (err >= 0) {
+ if (err == 0) {
+ /* E.g. GUP interrupted by fatal signal */
+ err = -EFAULT;
+ } else if (err > 0) {
err = page_to_nid(p);
put_page(p);
}