[PKTGEN]: Kill dead static inlines

[linux-2.6-omap-h63xx.git] / kernel / futex.c

diff --git a/kernel/futex.c b/kernel/futex.c
index 172a1aeeafdb5a148f6a0063bc3bc719b1974096..db9824de8bf061323b734d88377a6fa606fb9a86 100644 (file)
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -1097,15 +1097,15 @@ static void unqueue_me_pi(struct futex_q *q)
 }
 
 /*
- * Fixup the pi_state owner with current.
+ * Fixup the pi_state owner with the new owner.
  *
  * Must be called with hash bucket lock held and mm->sem held for non
  * private futexes.
  */
 static int fixup_pi_state_owner(u32 __user *uaddr, struct futex_q *q,
-                               struct task_struct *curr)
+                               struct task_struct *newowner)
 {
-       u32 newtid = task_pid_vnr(curr) | FUTEX_WAITERS;
+       u32 newtid = task_pid_vnr(newowner) | FUTEX_WAITERS;
        struct futex_pi_state *pi_state = q->pi_state;
        u32 uval, curval, newval;
        int ret;
@@ -1119,12 +1119,12 @@ static int fixup_pi_state_owner(u32 __user *uaddr, struct futex_q *q,
        } else
                newtid |= FUTEX_OWNER_DIED;
 
-       pi_state->owner = curr;
+       pi_state->owner = newowner;
 
-       spin_lock_irq(&curr->pi_lock);
+       spin_lock_irq(&newowner->pi_lock);
        WARN_ON(!list_empty(&pi_state->list));
-       list_add(&pi_state->list, &curr->pi_state_list);
-       spin_unlock_irq(&curr->pi_lock);
+       list_add(&pi_state->list, &newowner->pi_state_list);
+       spin_unlock_irq(&newowner->pi_lock);
 
        /*
         * We own it, so we have to replace the pending owner
@@ -1508,9 +1508,40 @@ static int futex_lock_pi(u32 __user *uaddr, struct rw_semaphore *fshared,
                 * when we were on the way back before we locked the
                 * hash bucket.
                 */
-               if (q.pi_state->owner == curr &&
-                   rt_mutex_trylock(&q.pi_state->pi_mutex)) {
-                       ret = 0;
+               if (q.pi_state->owner == curr) {
+                       /*
+                        * Try to get the rt_mutex now. This might
+                        * fail as some other task acquired the
+                        * rt_mutex after we removed ourself from the
+                        * rt_mutex waiters list.
+                        */
+                       if (rt_mutex_trylock(&q.pi_state->pi_mutex))
+                               ret = 0;
+                       else {
+                               /*
+                                * pi_state is incorrect, some other
+                                * task did a lock steal and we
+                                * returned due to timeout or signal
+                                * without taking the rt_mutex. Too
+                                * late. We can access the
+                                * rt_mutex_owner without locking, as
+                                * the other task is now blocked on
+                                * the hash bucket lock. Fix the state
+                                * up.
+                                */
+                               struct task_struct *owner;
+                               int res;
+
+                               owner = rt_mutex_owner(&q.pi_state->pi_mutex);
+                               res = fixup_pi_state_owner(uaddr, &q, owner);
+
+                               WARN_ON(rt_mutex_owner(&q.pi_state->pi_mutex) !=
+                                       owner);
+
+                               /* propagate -EFAULT, if the fixup failed */
+                               if (res)
+                                       ret = res;
+                       }
                } else {
                        /*
                         * Paranoia check. If we did not take the lock