- prev_usage_in_excess = mz->usage_in_excess;
-
- new_usage_in_excess = res_counter_soft_limit_excess(&mem->res);
- if (prev_usage_in_excess) {
- mem_cgroup_remove_exceeded(mem, mz, mctz);
- updated_tree = true;
- }
- if (!new_usage_in_excess)
- goto done;
- mem_cgroup_insert_exceeded(mem, mz, mctz);
-
-done:
- if (updated_tree) {
- spin_lock(&mctz->lock);
- mz->usage_in_excess = new_usage_in_excess;
- spin_unlock(&mctz->lock);
+ for (; mem; mem = parent_mem_cgroup(mem)) {
+ mz = mem_cgroup_zoneinfo(mem, nid, zid);
+ excess = res_counter_soft_limit_excess(&mem->res);
+ /*
+ * We have to update the tree if mz is on RB-tree or
+ * mem is over its softlimit.
+ */
+ if (excess || mz->on_tree) {
+ spin_lock(&mctz->lock);
+ /* if on-tree, remove it */
+ if (mz->on_tree)
+ __mem_cgroup_remove_exceeded(mem, mz, mctz);
+ /*
+ * Insert again. mz->usage_in_excess will be updated.
+ * If excess is 0, no tree ops.
+ */
+ __mem_cgroup_insert_exceeded(mem, mz, mctz, excess);
+ spin_unlock(&mctz->lock);
+ }