mempolicy: use MPOL_F_LOCAL to Indicate Preferred Local Policy

[pandora-kernel.git] / mm / mempolicy.c

diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 7b3ae97..143b019 100644 (file)
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -110,7 +110,7 @@ enum zone_type policy_zone = 0;
 struct mempolicy default_policy = {
        .refcnt = ATOMIC_INIT(1), /* never free it */
        .mode = MPOL_PREFERRED,
-       .v =  { .preferred_node =  -1 },
+       .flags = MPOL_F_LOCAL,
 };
 
 static const struct mempolicy_operations {
@@ -163,7 +163,7 @@ static int mpol_new_interleave(struct mempolicy *pol, const nodemask_t *nodes)
 static int mpol_new_preferred(struct mempolicy *pol, const nodemask_t *nodes)
 {
        if (!nodes)
-               pol->v.preferred_node = -1;     /* local allocation */
+               pol->flags |= MPOL_F_LOCAL;     /* local allocation */
        else if (nodes_empty(*nodes))
                return -EINVAL;                 /*  no allowed nodes */
        else
@@ -290,14 +290,15 @@ static void mpol_rebind_preferred(struct mempolicy *pol,
        if (pol->flags & MPOL_F_STATIC_NODES) {
                int node = first_node(pol->w.user_nodemask);
 
-               if (node_isset(node, *nodes))
+               if (node_isset(node, *nodes)) {
                        pol->v.preferred_node = node;
-               else
-                       pol->v.preferred_node = -1;
+                       pol->flags &= ~MPOL_F_LOCAL;
+               } else
+                       pol->flags |= MPOL_F_LOCAL;
        } else if (pol->flags & MPOL_F_RELATIVE_NODES) {
                mpol_relative_nodemask(&tmp, &pol->w.user_nodemask, nodes);
                pol->v.preferred_node = first_node(tmp);
-       } else if (pol->v.preferred_node != -1) {
+       } else if (!(pol->flags & MPOL_F_LOCAL)) {
                pol->v.preferred_node = node_remap(pol->v.preferred_node,
                                                   pol->w.cpuset_mems_allowed,
                                                   *nodes);
@@ -645,7 +646,7 @@ static void get_policy_nodemask(struct mempolicy *p, nodemask_t *nodes)
                *nodes = p->v.nodes;
                break;
        case MPOL_PREFERRED:
-               if (p->v.preferred_node >= 0)
+               if (!(p->flags & MPOL_F_LOCAL))
                        node_set(p->v.preferred_node, *nodes);
                /* else return empty node mask for local allocation */
                break;
@@ -1324,13 +1325,12 @@ static nodemask_t *policy_nodemask(gfp_t gfp, struct mempolicy *policy)
 /* Return a zonelist indicated by gfp for node representing a mempolicy */
 static struct zonelist *policy_zonelist(gfp_t gfp, struct mempolicy *policy)
 {
-       int nd;
+       int nd = numa_node_id();
 
        switch (policy->mode) {
        case MPOL_PREFERRED:
-               nd = policy->v.preferred_node;
-               if (nd < 0)
-                       nd = numa_node_id();
+               if (!(policy->flags & MPOL_F_LOCAL))
+                       nd = policy->v.preferred_node;
                break;
        case MPOL_BIND:
                /*
@@ -1339,16 +1339,13 @@ static struct zonelist *policy_zonelist(gfp_t gfp, struct mempolicy *policy)
                 * current node is part of the mask, we use the zonelist for
                 * the first node in the mask instead.
                 */
-               nd = numa_node_id();
                if (unlikely(gfp & __GFP_THISNODE) &&
                                unlikely(!node_isset(nd, policy->v.nodes)))
                        nd = first_node(policy->v.nodes);
                break;
        case MPOL_INTERLEAVE: /* should not happen */
-               nd = numa_node_id();
                break;
        default:
-               nd = 0;
                BUG();
        }
        return node_zonelist(nd, gfp);
@@ -1379,14 +1376,15 @@ static unsigned interleave_nodes(struct mempolicy *policy)
  */
 unsigned slab_node(struct mempolicy *policy)
 {
-       if (!policy)
+       if (!policy || policy->flags & MPOL_F_LOCAL)
                return numa_node_id();
 
        switch (policy->mode) {
        case MPOL_PREFERRED:
-               if (unlikely(policy->v.preferred_node >= 0))
-                       return policy->v.preferred_node;
-               return numa_node_id();
+               /*
+                * handled MPOL_F_LOCAL above
+                */
+               return policy->v.preferred_node;
 
        case MPOL_INTERLEAVE:
                return interleave_nodes(policy);
@@ -1666,7 +1664,8 @@ int __mpol_equal(struct mempolicy *a, struct mempolicy *b)
        case MPOL_INTERLEAVE:
                return nodes_equal(a->v.nodes, b->v.nodes);
        case MPOL_PREFERRED:
-               return a->v.preferred_node == b->v.preferred_node;
+               return a->v.preferred_node == b->v.preferred_node &&
+                       a->flags == b->flags;
        default:
                BUG();
                return 0;
@@ -1946,7 +1945,7 @@ void numa_default_policy(void)
 }
 
 /*
- * "local" is pseudo-policy:  MPOL_PREFERRED with preferred_node == -1
+ * "local" is pseudo-policy:  MPOL_PREFERRED with MPOL_F_LOCAL flag
  * Used only for mpol_to_str()
  */
 #define MPOL_LOCAL (MPOL_INTERLEAVE + 1)
@@ -1962,7 +1961,6 @@ 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;
@@ -1979,11 +1977,10 @@ static inline int mpol_to_str(char *buffer, int maxlen, struct mempolicy *pol)
 
        case MPOL_PREFERRED:
                nodes_clear(nodes);
-               nid = pol->v.preferred_node;
-               if (nid < 0)
+               if (flags & MPOL_F_LOCAL)
                        mode = MPOL_LOCAL;      /* pseudo-policy */
                else
-                       node_set(nid, nodes);
+                       node_set(pol->v.preferred_node, nodes);
                break;
 
        case MPOL_BIND:
@@ -2004,7 +2001,7 @@ static inline int mpol_to_str(char *buffer, int maxlen, struct mempolicy *pol)
        strcpy(p, policy_types[mode]);
        p += l;
 
-       if (flags) {
+       if (flags & MPOL_MODE_FLAGS) {
                int need_bar = 0;
 
                if (buffer + maxlen < p + 2)