4 files changed, 37 insertions, 8 deletions

diff --git a/include/linux/res_counter.h b/include/linux/res_counter.h
index d06d014afda6..da81af086eaf 100644
--- a/include/linux/res_counter.h
+++ b/include/linux/res_counter.h
@@ -109,12 +109,18 @@ void res_counter_init(struct res_counter *counter, struct res_counter *parent);
  *
  * returns 0 on success and <0 if the counter->usage will exceed the
  * counter->limit _locked call expects the counter->lock to be taken
+ *
+ * charge_nofail works the same, except that it charges the resource
+ * counter unconditionally, and returns < 0 if the after the current
+ * charge we are over limit.
  */
 
 int __must_check res_counter_charge_locked(struct res_counter *counter,
                 unsigned long val);
 int __must_check res_counter_charge(struct res_counter *counter,
                 unsigned long val, struct res_counter **limit_fail_at);
+int __must_check res_counter_charge_nofail(struct res_counter *counter,
+                unsigned long val, struct res_counter **limit_fail_at);
 
 /*
  * uncharge - tell that some portion of the resource is released
diff --git a/include/net/sock.h b/include/net/sock.h
index 0e7a9b05f92b..4c69ac165e6b 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -1008,9 +1008,8 @@ static inline void memcg_memory_allocated_add(struct cg_proto *prot,
         struct res_counter *fail;
         int ret;
 
-        ret = res_counter_charge(prot->memory_allocated,
-                                 amt << PAGE_SHIFT, &fail);
-
+        ret = res_counter_charge_nofail(prot->memory_allocated,
+                                        amt << PAGE_SHIFT, &fail);
         if (ret < 0)
                 *parent_status = OVER_LIMIT;
 }
@@ -1054,12 +1053,11 @@ sk_memory_allocated_add(struct sock *sk, int amt, int *parent_status)
 }
 
 static inline void
-sk_memory_allocated_sub(struct sock *sk, int amt, int parent_status)
+sk_memory_allocated_sub(struct sock *sk, int amt)
 {
         struct proto *prot = sk->sk_prot;
 
-        if (mem_cgroup_sockets_enabled && sk->sk_cgrp &&
-            parent_status != OVER_LIMIT) /* Otherwise was uncharged already */
+        if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
                 memcg_memory_allocated_sub(sk->sk_cgrp, amt);
 
         atomic_long_sub(amt, prot->memory_allocated);
diff --git a/kernel/res_counter.c b/kernel/res_counter.c
index 6d269cce7aa1..d508363858b3 100644
--- a/kernel/res_counter.c
+++ b/kernel/res_counter.c
@@ -66,6 +66,31 @@ done:
         return ret;
 }
 
+int res_counter_charge_nofail(struct res_counter *counter, unsigned long val,
+                              struct res_counter **limit_fail_at)
+{
+        int ret, r;
+        unsigned long flags;
+        struct res_counter *c;
+
+        r = ret = 0;
+        *limit_fail_at = NULL;
+        local_irq_save(flags);
+        for (c = counter; c != NULL; c = c->parent) {
+                spin_lock(&c->lock);
+                r = res_counter_charge_locked(c, val);
+                if (r)
+                        c->usage += val;
+                spin_unlock(&c->lock);
+                if (r < 0 && ret == 0) {
+                        *limit_fail_at = c;
+                        ret = r;
+                }
+        }
+        local_irq_restore(flags);
+
+        return ret;
+}
 void res_counter_uncharge_locked(struct res_counter *counter, unsigned long val)
 {
         if (WARN_ON(counter->usage < val))
diff --git a/net/core/sock.c b/net/core/sock.c
index 5c5af9988f94..3e81fd2e3c75 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -1827,7 +1827,7 @@ suppress_allocation:
         /* Alas. Undo changes. */
         sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
 
-        sk_memory_allocated_sub(sk, amt, parent_status);
+        sk_memory_allocated_sub(sk, amt);
 
         return 0;
 }
@@ -1840,7 +1840,7 @@ EXPORT_SYMBOL(__sk_mem_schedule);
 void __sk_mem_reclaim(struct sock *sk)
 {
         sk_memory_allocated_sub(sk,
-                                sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT, 0);
+                                sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT);
         sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1;
 
         if (sk_under_memory_pressure(sk) &&