mempolicy: mPOL_PREFERRED cleanups for "local allocation"

[net-next-2.6.git] / mm / mempolicy.c

diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index fea4a5da6e4453897b425b0cdab6e08718299382..7b3ae977b158e21677337549ece01befc33d21b0 100644 (file)
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -645,11 +645,9 @@ static void get_policy_nodemask(struct mempolicy *p, nodemask_t *nodes)
                *nodes = p->v.nodes;
                break;
        case MPOL_PREFERRED:
-               /* or use current node instead of memory_map? */
-               if (p->v.preferred_node < 0)
-                       *nodes = node_states[N_HIGH_MEMORY];
-               else
+               if (p->v.preferred_node >= 0)
                        node_set(p->v.preferred_node, *nodes);
+               /* else return empty node mask for local allocation */
                break;
        default:
                BUG();
@@ -804,7 +802,7 @@ int do_migrate_pages(struct mm_struct *mm,
        int err = 0;
        nodemask_t tmp;
 
-       down_read(&mm->mmap_sem);
+       down_read(&mm->mmap_sem);
 
        err = migrate_vmas(mm, from_nodes, to_nodes, flags);
        if (err)
@@ -1948,10 +1946,12 @@ void numa_default_policy(void)
 }
 
 /*
- * Display pages allocated per node and memory policy via /proc.
+ * "local" is pseudo-policy:  MPOL_PREFERRED with preferred_node == -1
+ * Used only for mpol_to_str()
  */
+#define MPOL_LOCAL (MPOL_INTERLEAVE + 1)
 static const char * const policy_types[] =
-       { "default", "prefer", "bind", "interleave" };
+       { "default", "prefer", "bind", "interleave", "local" };
 
 /*
  * Convert a mempolicy into a string.
@@ -1962,6 +1962,7 @@ static inline int mpol_to_str(char *buffer, int maxlen, struct mempolicy *pol)
 {
        char *p = buffer;
        int l;
+       int nid;
        nodemask_t nodes;
        unsigned short mode;
        unsigned short flags = pol ? pol->flags : 0;
@@ -1978,7 +1979,11 @@ static inline int mpol_to_str(char *buffer, int maxlen, struct mempolicy *pol)
 
        case MPOL_PREFERRED:
                nodes_clear(nodes);
-               node_set(pol->v.preferred_node, nodes);
+               nid = pol->v.preferred_node;
+               if (nid < 0)
+                       mode = MPOL_LOCAL;      /* pseudo-policy */
+               else
+                       node_set(nid, nodes);
                break;
 
        case MPOL_BIND:
@@ -1993,8 +1998,8 @@ static inline int mpol_to_str(char *buffer, int maxlen, struct mempolicy *pol)
        }
 
        l = strlen(policy_types[mode]);
-       if (buffer + maxlen < p + l + 1)
-               return -ENOSPC;
+       if (buffer + maxlen < p + l + 1)
+               return -ENOSPC;
 
        strcpy(p, policy_types[mode]);
        p += l;
@@ -2093,6 +2098,9 @@ static inline void check_huge_range(struct vm_area_struct *vma,
 }
 #endif
 
+/*
+ * Display pages allocated per node and memory policy via /proc.
+ */
 int show_numa_map(struct seq_file *m, void *v)
 {
        struct proc_maps_private *priv = m->private;