1 files changed, 9 insertions, 406 deletions

diff --git a/kernel/futex.c b/kernel/futex.c
index 3b7f771..df248f5 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -56,12 +56,6 @@
 
 #include "rtmutex_common.h"
 
-#ifdef CONFIG_DEBUG_RT_MUTEXES
-# include "rtmutex-debug.h"
-#else
-# include "rtmutex.h"
-#endif
-
 #define FUTEX_HASHBITS (CONFIG_BASE_SMALL ? 4 : 8)
 
 /*
@@ -111,12 +105,6 @@ struct futex_q {
 	/* Optional priority inheritance state: */
 	struct futex_pi_state *pi_state;
 	struct task_struct *task;
-
-	/*
-	 * This waiter is used in case of requeue from a
-	 * normal futex to a PI-futex
-	 */
-	struct rt_mutex_waiter waiter;
 };
 
 /*
@@ -216,9 +204,6 @@ int get_futex_key(u32 __user *uaddr, struct rw_semaphore *fshared,
 	if (unlikely((vma->vm_flags & (VM_IO|VM_READ)) != VM_READ))
 		return (vma->vm_flags & VM_IO) ? -EPERM : -EACCES;
 
-	/* Save the user address in the ley */
-	key->uaddr = uaddr;
-
 	/*
 	 * Private mappings are handled in a simple way.
 	 *
@@ -636,8 +621,6 @@ static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_q *this)
 		int ret = 0;
 
 		newval = FUTEX_WAITERS | new_owner->pid;
-		/* Keep the FUTEX_WAITER_REQUEUED flag if it was set */
-		newval |= (uval & FUTEX_WAITER_REQUEUED);
 
 		pagefault_disable();
 		curval = futex_atomic_cmpxchg_inatomic(uaddr, uval, newval);
@@ -750,259 +733,6 @@ out:
 }
 
 /*
- * Called from futex_requeue_pi.
- * Set FUTEX_WAITERS and FUTEX_WAITER_REQUEUED flags on the
- * PI-futex value; search its associated pi_state if an owner exist
- * or create a new one without owner.
- */
-static inline int
-lookup_pi_state_for_requeue(u32 __user *uaddr, struct futex_hash_bucket *hb,
-			    union futex_key *key,
-			    struct futex_pi_state **pi_state)
-{
-	u32 curval, uval, newval;
-
-retry:
-	/*
-	 * We can't handle a fault cleanly because we can't
-	 * release the locks here. Simply return the fault.
-	 */
-	if (get_futex_value_locked(&curval, uaddr))
-		return -EFAULT;
-
-	/* set the flags FUTEX_WAITERS and FUTEX_WAITER_REQUEUED */
-	if ((curval & (FUTEX_WAITERS | FUTEX_WAITER_REQUEUED))
-	    != (FUTEX_WAITERS | FUTEX_WAITER_REQUEUED)) {
-		/*
-		 * No waiters yet, we prepare the futex to have some waiters.
-		 */
-
-		uval = curval;
-		newval = uval | FUTEX_WAITERS | FUTEX_WAITER_REQUEUED;
-
-		pagefault_disable();
-		curval = futex_atomic_cmpxchg_inatomic(uaddr, uval, newval);
-		pagefault_enable();
-
-		if (unlikely(curval == -EFAULT))
-			return -EFAULT;
-		if (unlikely(curval != uval))
-			goto retry;
-	}
-
-	if (!(curval & FUTEX_TID_MASK)
-	    || lookup_pi_state(curval, hb, key, pi_state)) {
-		/* the futex has no owner (yet) or the lookup failed:
-		   allocate one pi_state without owner */
-
-		*pi_state = alloc_pi_state();
-
-		/* Already stores the key: */
-		(*pi_state)->key = *key;
-
-		/* init the mutex without owner */
-		__rt_mutex_init(&(*pi_state)->pi_mutex, NULL);
-	}
-
-	return 0;
-}
-
-/*
- * Keep the first nr_wake waiter from futex1, wake up one,
- * and requeue the next nr_requeue waiters following hashed on
- * one physical page to another physical page (PI-futex uaddr2)
- */
-static int futex_requeue_pi(u32 __user *uaddr1,
-			    struct rw_semaphore *fshared,
-			    u32 __user *uaddr2,
-			    int nr_wake, int nr_requeue, u32 *cmpval)
-{
-	union futex_key key1, key2;
-	struct futex_hash_bucket *hb1, *hb2;
-	struct plist_head *head1;
-	struct futex_q *this, *next;
-	struct futex_pi_state *pi_state2 = NULL;
-	struct rt_mutex_waiter *waiter, *top_waiter = NULL;
-	struct rt_mutex *lock2 = NULL;
-	int ret, drop_count = 0;
-
-	if (refill_pi_state_cache())
-		return -ENOMEM;
-
-retry:
-	/*
-	 * First take all the futex related locks:
-	 */
-	if (fshared)
-		down_read(fshared);
-
-	ret = get_futex_key(uaddr1, fshared, &key1);
-	if (unlikely(ret != 0))
-		goto out;
-	ret = get_futex_key(uaddr2, fshared, &key2);
-	if (unlikely(ret != 0))
-		goto out;
-
-	hb1 = hash_futex(&key1);
-	hb2 = hash_futex(&key2);
-
-	double_lock_hb(hb1, hb2);
-
-	if (likely(cmpval != NULL)) {
-		u32 curval;
-
-		ret = get_futex_value_locked(&curval, uaddr1);
-
-		if (unlikely(ret)) {
-			spin_unlock(&hb1->lock);
-			if (hb1 != hb2)
-				spin_unlock(&hb2->lock);
-
-			/*
-			 * If we would have faulted, release mmap_sem, fault
-			 * it in and start all over again.
-			 */
-			if (fshared)
-				up_read(fshared);
-
-			ret = get_user(curval, uaddr1);
-
-			if (!ret)
-				goto retry;
-
-			return ret;
-		}
-		if (curval != *cmpval) {
-			ret = -EAGAIN;
-			goto out_unlock;
-		}
-	}
-
-	head1 = &hb1->chain;
-	plist_for_each_entry_safe(this, next, head1, list) {
-		if (!match_futex (&this->key, &key1))
-			continue;
-		if (++ret <= nr_wake) {
-			wake_futex(this);
-		} else {
-			/*
-			 * FIRST: get and set the pi_state
-			 */
-			if (!pi_state2) {
-				int s;
-				/* do this only the first time we requeue someone */
-				s = lookup_pi_state_for_requeue(uaddr2, hb2,
-								&key2, &pi_state2);
-				if (s) {
-					ret = s;
-					goto out_unlock;
-				}
-
-				lock2 = &pi_state2->pi_mutex;
-				spin_lock(&lock2->wait_lock);
-
-				/* Save the top waiter of the wait_list */
-				if (rt_mutex_has_waiters(lock2))
-					top_waiter = rt_mutex_top_waiter(lock2);
-			} else
-				atomic_inc(&pi_state2->refcount);
-
-
-			this->pi_state = pi_state2;
-
-			/*
-			 * SECOND: requeue futex_q to the correct hashbucket
-			 */
-
-			/*
-			 * If key1 and key2 hash to the same bucket, no need to
-			 * requeue.
-			 */
-			if (likely(head1 != &hb2->chain)) {
-				plist_del(&this->list, &hb1->chain);
-				plist_add(&this->list, &hb2->chain);
-				this->lock_ptr = &hb2->lock;
-#ifdef CONFIG_DEBUG_PI_LIST
-				this->list.plist.lock = &hb2->lock;
-#endif
-			}
-			this->key = key2;
-			get_futex_key_refs(&key2);
-			drop_count++;
-
-
-			/*
-			 * THIRD: queue it to lock2
-			 */
-			spin_lock_irq(&this->task->pi_lock);
-			waiter = &this->waiter;
-			waiter->task = this->task;
-			waiter->lock = lock2;
-			plist_node_init(&waiter->list_entry, this->task->prio);
-			plist_node_init(&waiter->pi_list_entry, this->task->prio);
-			plist_add(&waiter->list_entry, &lock2->wait_list);
-			this->task->pi_blocked_on = waiter;
-			spin_unlock_irq(&this->task->pi_lock);
-
-			if (ret - nr_wake >= nr_requeue)
-				break;
-		}
-	}
-
-	/* If we've requeued some tasks and the top_waiter of the rt_mutex
-	   has changed, we must adjust the priority of the owner, if any */
-	if (drop_count) {
-		struct task_struct *owner = rt_mutex_owner(lock2);
-		if (owner &&
-		    (top_waiter != (waiter = rt_mutex_top_waiter(lock2)))) {
-			int chain_walk = 0;
-
-			spin_lock_irq(&owner->pi_lock);
-			if (top_waiter)
-				plist_del(&top_waiter->pi_list_entry, &owner->pi_waiters);
-			else
-				/*
-				 * There was no waiters before the requeue,
-				 * the flag must be updated
-				 */
-				mark_rt_mutex_waiters(lock2);
-
-			plist_add(&waiter->pi_list_entry, &owner->pi_waiters);
-			__rt_mutex_adjust_prio(owner);
-			if (owner->pi_blocked_on) {
-				chain_walk = 1;
-				get_task_struct(owner);
-			}
-
-			spin_unlock_irq(&owner->pi_lock);
-			spin_unlock(&lock2->wait_lock);
-
-			if (chain_walk)
-				rt_mutex_adjust_prio_chain(owner, 0, lock2, NULL,
-							   current);
-		} else {
-			/* No owner or the top_waiter does not change */
-			mark_rt_mutex_waiters(lock2);
-			spin_unlock(&lock2->wait_lock);
-		}
-	}
-
-out_unlock:
-	spin_unlock(&hb1->lock);
-	if (hb1 != hb2)
-		spin_unlock(&hb2->lock);
-
-	/* drop_futex_key_refs() must be called outside the spinlocks. */
-	while (--drop_count >= 0)
-		drop_futex_key_refs(&key1);
-
-out:
-	if (fshared)
-		up_read(fshared);
-	return ret;
-}
-
-/*
  * Wake up all waiters hashed on the physical page that is mapped
  * to this virtual address:
  */
@@ -1384,7 +1114,6 @@ static int fixup_pi_state_owner(u32 __user *uaddr, struct futex_q *q,
 
 	while (!ret) {
 		newval = (uval & FUTEX_OWNER_DIED) | newtid;
-		newval |= (uval & FUTEX_WAITER_REQUEUED);
 
 		pagefault_disable();
 		curval = futex_atomic_cmpxchg_inatomic(uaddr,
@@ -1416,7 +1145,7 @@ static int futex_wait(u32 __user *uaddr, struct rw_semaphore *fshared,
 	struct futex_q q;
 	u32 uval;
 	int ret;
-	struct hrtimer_sleeper t, *to = NULL;
+	struct hrtimer_sleeper t;
 	int rem = 0;
 
 	q.pi_state = NULL;
@@ -1472,14 +1201,6 @@ static int futex_wait(u32 __user *uaddr, struct rw_semaphore *fshared,
 	if (uval != val)
 		goto out_unlock_release_sem;
 
-	/*
-	 * This rt_mutex_waiter structure is prepared here and will
-	 * be used only if this task is requeued from a normal futex to
-	 * a PI-futex with futex_requeue_pi.
-	 */
-	debug_rt_mutex_init_waiter(&q.waiter);
-	q.waiter.task = NULL;
-
 	/* Only actually queue if *uaddr contained val.  */
 	__queue_me(&q, hb);
 
@@ -1510,7 +1231,6 @@ static int futex_wait(u32 __user *uaddr, struct rw_semaphore *fshared,
 		if (!abs_time)
 			schedule();
 		else {
-			to = &t;
 			hrtimer_init(&t.timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
 			hrtimer_init_sleeper(&t, current);
 			t.timer.expires = *abs_time;
@@ -1538,67 +1258,6 @@ static int futex_wait(u32 __user *uaddr, struct rw_semaphore *fshared,
 	 * we are the only user of it.
 	 */
 
-	if (q.pi_state) {
-		/*
-		 * We were woken but have been requeued on a PI-futex.
-		 * We have to complete the lock acquisition by taking
-		 * the rtmutex.
-		 */
-
-		struct rt_mutex *lock = &q.pi_state->pi_mutex;
-
-		spin_lock(&lock->wait_lock);
-		if (unlikely(q.waiter.task)) {
-			remove_waiter(lock, &q.waiter);
-		}
-		spin_unlock(&lock->wait_lock);
-
-		if (rem)
-			ret = -ETIMEDOUT;
-		else
-			ret = rt_mutex_timed_lock(lock, to, 1);
-
-		if (fshared)
-			down_read(fshared);
-		spin_lock(q.lock_ptr);
-
-		/*
-		 * Got the lock. We might not be the anticipated owner if we
-		 * did a lock-steal - fix up the PI-state in that case.
-		 */
-		if (!ret && q.pi_state->owner != curr) {
-			/*
-			 * We MUST play with the futex we were requeued on,
-			 * NOT the current futex.
-			 * We can retrieve it from the key of the pi_state
-			 */
-			uaddr = q.pi_state->key.uaddr;
-
-			ret = fixup_pi_state_owner(uaddr, &q, curr);
-		} else {
-			/*
-			 * Catch the rare case, where the lock was released
-			 * when we were on the way back before we locked
-			 * the hash bucket.
-			 */
-			if (ret && q.pi_state->owner == curr) {
-				if (rt_mutex_trylock(&q.pi_state->pi_mutex))
-					ret = 0;
-			}
-		}
-
-		/* Unqueue and drop the lock */
-		unqueue_me_pi(&q);
-		if (fshared)
-			up_read(fshared);
-
-		debug_rt_mutex_free_waiter(&q.waiter);
-
-		return ret;
-	}
-
-	debug_rt_mutex_free_waiter(&q.waiter);
-
 	/* If we were woken (and unqueued), we succeeded, whatever. */
 	if (!unqueue_me(&q))
 		return 0;
@@ -1648,51 +1307,6 @@ static long futex_wait_restart(struct restart_block *restart)
 }
 
 
-static void set_pi_futex_owner(struct futex_hash_bucket *hb,
-			       union futex_key *key, struct task_struct *p)
-{
-	struct plist_head *head;
-	struct futex_q *this, *next;
-	struct futex_pi_state *pi_state = NULL;
-	struct rt_mutex *lock;
-
-	/* Search a waiter that should already exists */
-
-	head = &hb->chain;
-
-	plist_for_each_entry_safe(this, next, head, list) {
-		if (match_futex (&this->key, key)) {
-			pi_state = this->pi_state;
-			break;
-		}
-	}
-
-	BUG_ON(!pi_state);
-
-	/* set p as pi_state's owner */
-	lock = &pi_state->pi_mutex;
-
-	spin_lock(&lock->wait_lock);
-	spin_lock_irq(&p->pi_lock);
-
-	list_add(&pi_state->list, &p->pi_state_list);
-	pi_state->owner = p;
-
-
-	/* set p as pi_mutex's owner */
-	debug_rt_mutex_proxy_lock(lock, p);
-	WARN_ON(rt_mutex_owner(lock));
-	rt_mutex_set_owner(lock, p, 0);
-	rt_mutex_deadlock_account_lock(lock, p);
-
-	plist_add(&rt_mutex_top_waiter(lock)->pi_list_entry,
-		  &p->pi_waiters);
-	__rt_mutex_adjust_prio(p);
-
-	spin_unlock_irq(&p->pi_lock);
-	spin_unlock(&lock->wait_lock);
-}
-
 /*
  * Userspace tried a 0 -> TID atomic transition of the futex value
  * and failed. The kernel side here does the whole locking operation:
@@ -1753,8 +1367,7 @@ static int futex_lock_pi(u32 __user *uaddr, struct rw_semaphore *fshared,
 	 * situation and we return success to user space.
 	 */
 	if (unlikely((curval & FUTEX_TID_MASK) == current->pid)) {
-		if (!(curval & FUTEX_WAITER_REQUEUED))
-			ret = -EDEADLK;
+		ret = -EDEADLK;
 		goto out_unlock_release_sem;
 	}
 
@@ -1774,14 +1387,14 @@ static int futex_lock_pi(u32 __user *uaddr, struct rw_semaphore *fshared,
 
 	/*
 	 * There are two cases, where a futex might have no owner (the
-	 * owner TID is 0): OWNER_DIED or REQUEUE. We take over the
-	 * futex in this case. We also do an unconditional take over,
-	 * when the owner of the futex died.
+	 * owner TID is 0): OWNER_DIED. We take over the futex in this
+	 * case. We also do an unconditional take over, when the owner
+	 * of the futex died.
 	 *
 	 * This is safe as we are protected by the hash bucket lock !
 	 */
 	if (unlikely(ownerdied || !(curval & FUTEX_TID_MASK))) {
-		/* Keep the OWNER_DIED and REQUEUE bits */
+		/* Keep the OWNER_DIED bit */
 		newval = (curval & ~FUTEX_TID_MASK) | current->pid;
 		ownerdied = 0;
 		lock_taken = 1;
@@ -1797,14 +1410,10 @@ static int futex_lock_pi(u32 __user *uaddr, struct rw_semaphore *fshared,
 		goto retry_locked;
 
 	/*
-	 * We took the lock due to requeue or owner died take over.
+	 * We took the lock due to owner died take over.
 	 */
-	if (unlikely(lock_taken)) {
-		/* For requeue we need to fixup the pi_futex */
-		if (curval & FUTEX_WAITER_REQUEUED)
-			set_pi_futex_owner(hb, &q.key, curr);
+	if (unlikely(lock_taken))
 		goto out_unlock_release_sem;
-	}
 
 	/*
 	 * We dont have the lock. Look up the PI state (or create it if
@@ -2289,8 +1898,6 @@ retry:
 		 * userspace.
 		 */
 		mval = (uval & FUTEX_WAITERS) | FUTEX_OWNER_DIED;
-		/* Also keep the FUTEX_WAITER_REQUEUED flag if set */
-		mval |= (uval & FUTEX_WAITER_REQUEUED);
 		nval = futex_atomic_cmpxchg_inatomic(uaddr, uval, mval);
 
 		if (nval == -EFAULT)
@@ -2427,9 +2034,6 @@ long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout,
 	case FUTEX_TRYLOCK_PI:
 		ret = futex_lock_pi(uaddr, fshared, 0, timeout, 1);
 		break;
-	case FUTEX_CMP_REQUEUE_PI:
-		ret = futex_requeue_pi(uaddr, fshared, uaddr2, val, val2, &val3);
-		break;
 	default:
 		ret = -ENOSYS;
 	}
@@ -2460,8 +2064,7 @@ asmlinkage long sys_futex(u32 __user *uaddr, int op, u32 val,
 	/*
 	 * requeue parameter in 'utime' if cmd == FUTEX_REQUEUE.
 	 */
-	if (cmd == FUTEX_REQUEUE || cmd == FUTEX_CMP_REQUEUE
-	    || cmd == FUTEX_CMP_REQUEUE_PI)
+	if (cmd == FUTEX_REQUEUE || cmd == FUTEX_CMP_REQUEUE)
 		val2 = (u32) (unsigned long) utime;
 
 	return do_futex(uaddr, op, val, tp, uaddr2, val2, val3);