diff options
| -rw-r--r-- | mm/mempolicy.c | 17 |
1 files changed, 13 insertions, 4 deletions
diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 5e90b3fb7794..b44f54768766 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -1979,17 +1979,26 @@ unsigned int mempolicy_slab_node(void) */ static unsigned offset_il_node(struct mempolicy *pol, unsigned long n) { - unsigned nnodes = nodes_weight(pol->nodes); - unsigned target; + nodemask_t nodemask = pol->nodes; + unsigned int target, nnodes; int i; int nid; + /* + * The barrier will stabilize the nodemask in a register or on + * the stack so that it will stop changing under the code. + * + * Between first_node() and next_node(), pol->nodes could be changed + * by other threads. So we put pol->nodes in a local stack. + */ + barrier(); + nnodes = nodes_weight(nodemask); if (!nnodes) return numa_node_id(); target = (unsigned int)n % nnodes; - nid = first_node(pol->nodes); + nid = first_node(nodemask); for (i = 0; i < target; i++) - nid = next_node(nid, pol->nodes); + nid = next_node(nid, nodemask); return nid; } |