}
}
-/*
- * This function returns the number of memcg under hierarchy tree. Returns
- * 1(self count) if no children.
- */
-static int mem_cgroup_count_children(struct mem_cgroup *memcg)
-{
- int num = 0;
- struct mem_cgroup *iter;
-
- for_each_mem_cgroup_tree(iter, memcg)
- num++;
- return num;
-}
-
/*
* Return the memory (and swap, if configured) limit for a memcg.
*/
static int mem_cgroup_resize_limit(struct mem_cgroup *memcg,
unsigned long limit, bool memsw)
{
- unsigned long curusage;
- unsigned long oldusage;
bool enlarge = false;
- int retry_count;
int ret;
bool limits_invariant;
struct page_counter *counter = memsw ? &memcg->memsw : &memcg->memory;
- /*
- * For keeping hierarchical_reclaim simple, how long we should retry
- * is depends on callers. We set our retry-count to be function
- * of # of children which we should visit in this loop.
- */
- retry_count = MEM_CGROUP_RECLAIM_RETRIES *
- mem_cgroup_count_children(memcg);
-
- oldusage = page_counter_read(counter);
-
do {
if (signal_pending(current)) {
ret = -EINTR;
if (!ret)
break;
- try_to_free_mem_cgroup_pages(memcg, 1, GFP_KERNEL, !memsw);
-
- curusage = page_counter_read(counter);
- /* Usage is reduced ? */
- if (curusage >= oldusage)
- retry_count--;
- else
- oldusage = curusage;
- } while (retry_count);
+ if (!try_to_free_mem_cgroup_pages(memcg, 1,
+ GFP_KERNEL, !memsw)) {
+ ret = -EBUSY;
+ break;
+ }
+ } while (true);
if (!ret && enlarge)
memcg_oom_recover(memcg);