iter != NULL; \
iter = mem_cgroup_iter(NULL, iter, NULL))
+/**
+ * mem_cgroup_scan_tasks - iterate over tasks of a memory cgroup hierarchy
+ * @memcg: hierarchy root
+ * @fn: function to call for each task
+ * @arg: argument passed to @fn
+ *
+ * This function iterates over tasks attached to @memcg or to any of its
+ * descendants and calls @fn for each task. If @fn returns a non-zero
+ * value, the function breaks the iteration loop and returns the value.
+ * Otherwise, it will iterate over all tasks and return 0.
+ *
+ * This function must not be called for the root memory cgroup.
+ */
+int mem_cgroup_scan_tasks(struct mem_cgroup *memcg,
+ int (*fn)(struct task_struct *, void *), void *arg)
+{
+ struct mem_cgroup *iter;
+ int ret = 0;
+
+ BUG_ON(memcg == root_mem_cgroup);
+
+ for_each_mem_cgroup_tree(iter, memcg) {
+ struct css_task_iter it;
+ struct task_struct *task;
+
+ css_task_iter_start(&iter->css, &it);
+ while (!ret && (task = css_task_iter_next(&it)))
+ ret = fn(task, arg);
+ css_task_iter_end(&it);
+ if (ret) {
+ mem_cgroup_iter_break(memcg, iter);
+ break;
+ }
+ }
+ return ret;
+}
+
/**
* mem_cgroup_page_lruvec - return lruvec for isolating/putting an LRU page
* @page: the page
/*
* Return the memory (and swap, if configured) limit for a memcg.
*/
-static unsigned long mem_cgroup_get_limit(struct mem_cgroup *memcg)
+unsigned long mem_cgroup_get_limit(struct mem_cgroup *memcg)
{
unsigned long limit;
.gfp_mask = gfp_mask,
.order = order,
};
- struct mem_cgroup *iter;
- unsigned long chosen_points = 0;
- unsigned long totalpages;
- unsigned int points = 0;
- struct task_struct *chosen = NULL;
+ bool ret;
mutex_lock(&oom_lock);
-
- /*
- * If current has a pending SIGKILL or is exiting, then automatically
- * select it. The goal is to allow it to allocate so that it may
- * quickly exit and free its memory.
- */
- if (task_will_free_mem(current)) {
- mark_oom_victim(current);
- wake_oom_reaper(current);
- goto unlock;
- }
-
- check_panic_on_oom(&oc, CONSTRAINT_MEMCG);
- totalpages = mem_cgroup_get_limit(memcg) ? : 1;
- for_each_mem_cgroup_tree(iter, memcg) {
- struct css_task_iter it;
- struct task_struct *task;
-
- css_task_iter_start(&iter->css, &it);
- while ((task = css_task_iter_next(&it))) {
- switch (oom_scan_process_thread(&oc, task)) {
- case OOM_SCAN_SELECT:
- if (chosen)
- put_task_struct(chosen);
- chosen = task;
- chosen_points = ULONG_MAX;
- get_task_struct(chosen);
- /* fall through */
- case OOM_SCAN_CONTINUE:
- continue;
- case OOM_SCAN_ABORT:
- css_task_iter_end(&it);
- mem_cgroup_iter_break(memcg, iter);
- if (chosen)
- put_task_struct(chosen);
- /* Set a dummy value to return "true". */
- chosen = (void *) 1;
- goto unlock;
- case OOM_SCAN_OK:
- break;
- };
- points = oom_badness(task, memcg, NULL, totalpages);
- if (!points || points < chosen_points)
- continue;
- /* Prefer thread group leaders for display purposes */
- if (points == chosen_points &&
- thread_group_leader(chosen))
- continue;
-
- if (chosen)
- put_task_struct(chosen);
- chosen = task;
- chosen_points = points;
- get_task_struct(chosen);
- }
- css_task_iter_end(&it);
- }
-
- if (chosen) {
- points = chosen_points * 1000 / totalpages;
- oom_kill_process(&oc, chosen, points, totalpages,
- "Memory cgroup out of memory");
- }
-unlock:
+ ret = out_of_memory(&oc);
mutex_unlock(&oom_lock);
- return chosen;
+ return ret;
}
#if MAX_NUMNODES > 1
if (!memcg)
return false;
- if (!handle || oom_killer_disabled)
+ if (!handle)
goto cleanup;
owait.memcg = memcg;
static void mem_cgroup_id_get_many(struct mem_cgroup *memcg, unsigned int n)
{
+ VM_BUG_ON(atomic_read(&memcg->id.ref) <= 0);
atomic_add(n, &memcg->id.ref);
}
static void mem_cgroup_id_put_many(struct mem_cgroup *memcg, unsigned int n)
{
+ VM_BUG_ON(atomic_read(&memcg->id.ref) < n);
if (atomic_sub_and_test(n, &memcg->id.ref)) {
idr_remove(&mem_cgroup_idr, memcg->id.id);
memcg->id.id = 0;
static int mem_cgroup_css_online(struct cgroup_subsys_state *css)
{
+ struct mem_cgroup *memcg = mem_cgroup_from_css(css);
+
/* Online state pins memcg ID, memcg ID pins CSS */
- mem_cgroup_id_get(mem_cgroup_from_css(css));
+ atomic_set(&memcg->id.ref, 1);
css_get(css);
return 0;
}
.mm = mm,
};
down_read(&mm->mmap_sem);
- walk_page_range(0, ~0UL, &mem_cgroup_count_precharge_walk);
+ walk_page_range(0, mm->highest_vm_end,
+ &mem_cgroup_count_precharge_walk);
up_read(&mm->mmap_sem);
precharge = mc.precharge;
* When we have consumed all precharges and failed in doing
* additional charge, the page walk just aborts.
*/
- walk_page_range(0, ~0UL, &mem_cgroup_move_charge_walk);
+ walk_page_range(0, mc.mm->highest_vm_end, &mem_cgroup_move_charge_walk);
+
up_read(&mc.mm->mmap_sem);
atomic_dec(&mc.from->moving_account);
}