/* Used for OOM nofiier */
#define OOM_CONTROL (0)
+static inline bool should_force_charge(void)
+{
+ return tsk_is_oom_victim(current) || fatal_signal_pending(current) ||
+ (current->flags & PF_EXITING);
+}
+
/* Some nice accessors for the vmpressure. */
struct vmpressure *memcg_to_vmpressure(struct mem_cgroup *memcg)
{
if (unlikely(!memcg))
memcg = root_mem_cgroup;
}
- } while (!css_tryget_online(&memcg->css));
+ } while (!css_tryget(&memcg->css));
rcu_read_unlock();
return memcg;
}
css_put(&prev->css);
}
-static void invalidate_reclaim_iterators(struct mem_cgroup *dead_memcg)
+static void __invalidate_reclaim_iterators(struct mem_cgroup *from,
+ struct mem_cgroup *dead_memcg)
{
- struct mem_cgroup *memcg = dead_memcg;
struct mem_cgroup_reclaim_iter *iter;
struct mem_cgroup_per_node *mz;
int nid;
int i;
- while ((memcg = parent_mem_cgroup(memcg))) {
- for_each_node(nid) {
- mz = mem_cgroup_nodeinfo(memcg, nid);
- for (i = 0; i <= DEF_PRIORITY; i++) {
- iter = &mz->iter[i];
- cmpxchg(&iter->position,
- dead_memcg, NULL);
- }
+ for_each_node(nid) {
+ mz = mem_cgroup_nodeinfo(from, nid);
+ for (i = 0; i <= DEF_PRIORITY; i++) {
+ iter = &mz->iter[i];
+ cmpxchg(&iter->position,
+ dead_memcg, NULL);
}
}
}
+static void invalidate_reclaim_iterators(struct mem_cgroup *dead_memcg)
+{
+ struct mem_cgroup *memcg = dead_memcg;
+ struct mem_cgroup *last;
+
+ do {
+ __invalidate_reclaim_iterators(memcg, dead_memcg);
+ last = memcg;
+ } while ((memcg = parent_mem_cgroup(memcg)));
+
+ /*
+ * When cgruop1 non-hierarchy mode is used,
+ * parent_mem_cgroup() does not walk all the way up to the
+ * cgroup root (root_mem_cgroup). So we have to handle
+ * dead_memcg from cgroup root separately.
+ */
+ if (last != root_mem_cgroup)
+ __invalidate_reclaim_iterators(root_mem_cgroup,
+ dead_memcg);
+}
+
/*
* Iteration constructs for visiting all cgroups (under a tree). If
* loops are exited prematurely (break), mem_cgroup_iter_break() must
};
bool ret;
- mutex_lock(&oom_lock);
- ret = out_of_memory(&oc);
+ if (mutex_lock_killable(&oom_lock))
+ return true;
+ /*
+ * A few threads which were not waiting at mutex_lock_killable() can
+ * fail to bail out. Therefore, check again after holding oom_lock.
+ */
+ ret = should_force_charge() || out_of_memory(&oc);
mutex_unlock(&oom_lock);
return ret;
}
goto retry;
}
+ /*
+ * Memcg doesn't have a dedicated reserve for atomic
+ * allocations. But like the global atomic pool, we need to
+ * put the burden of reclaim on regular allocation requests
+ * and let these go through as privileged allocations.
+ */
+ if (gfp_mask & __GFP_ATOMIC)
+ goto force;
+
/*
* Unlike in global OOM situations, memcg is not in a physical
* memory shortage. Allow dying and OOM-killed tasks to
* bypass the last charges so that they can exit quickly and
* free their memory.
*/
- if (unlikely(tsk_is_oom_victim(current) ||
- fatal_signal_pending(current) ||
- current->flags & PF_EXITING))
+ if (unlikely(should_force_charge()))
goto force;
/*
{
struct memcg_kmem_cache_create_work *cw;
- cw = kmalloc(sizeof(*cw), GFP_NOWAIT);
+ cw = kmalloc(sizeof(*cw), GFP_NOWAIT | __GFP_NOWARN);
if (!cw)
return;
if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) &&
!page_counter_try_charge(&memcg->kmem, nr_pages, &counter)) {
+
+ /*
+ * Enforce __GFP_NOFAIL allocation because callers are not
+ * prepared to see failures and likely do not have any failure
+ * handling code.
+ */
+ if (gfp & __GFP_NOFAIL) {
+ page_counter_charge(&memcg->kmem, nr_pages);
+ return 0;
+ }
cancel_charge(memcg, nr_pages);
return -ENOMEM;
}
struct mem_cgroup *memcg;
int ret = 0;
- if (memcg_kmem_bypass())
+ if (mem_cgroup_disabled() || memcg_kmem_bypass())
return 0;
memcg = get_mem_cgroup_from_mm(current->mm);
static DEFINE_IDR(mem_cgroup_idr);
+static void mem_cgroup_id_remove(struct mem_cgroup *memcg)
+{
+ if (memcg->id.id > 0) {
+ idr_remove(&mem_cgroup_idr, memcg->id.id);
+ memcg->id.id = 0;
+ }
+}
+
static void mem_cgroup_id_get_many(struct mem_cgroup *memcg, unsigned int n)
{
VM_BUG_ON(atomic_read(&memcg->id.ref) <= 0);
{
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;
+ mem_cgroup_id_remove(memcg);
/* Memcg ID pins CSS */
css_put(&memcg->css);
{
struct mem_cgroup_per_node *pn = memcg->nodeinfo[node];
+ if (!pn)
+ return;
+
free_percpu(pn->lruvec_stat);
kfree(pn);
}
idr_replace(&mem_cgroup_idr, memcg, memcg->id.id);
return memcg;
fail:
- if (memcg->id.id > 0)
- idr_remove(&mem_cgroup_idr, memcg->id.id);
+ mem_cgroup_id_remove(memcg);
__mem_cgroup_free(memcg);
return NULL;
}
return &memcg->css;
fail:
+ mem_cgroup_id_remove(memcg);
mem_cgroup_free(memcg);
return ERR_PTR(-ENOMEM);
}
if (!mem_cgroup_sockets_enabled)
return;
+ /*
+ * Socket cloning can throw us here with sk_memcg already
+ * filled. It won't however, necessarily happen from
+ * process context. So the test for root memcg given
+ * the current task's memcg won't help us in this case.
+ *
+ * Respecting the original socket's memcg is a better
+ * decision in this case.
+ */
+ if (sk->sk_memcg) {
+ css_get(&sk->sk_memcg->css);
+ return;
+ }
+
rcu_read_lock();
memcg = mem_cgroup_from_task(current);
if (memcg == root_mem_cgroup)
projects / mirror_ubuntu-bionic-kernel.git / blobdiff