Merge master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6

[pandora-kernel.git] / kernel / futex.c

diff --git a/kernel/futex.c b/kernel/futex.c
index 6c91f93..1dc98e4 100644 (file)
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -606,6 +606,22 @@ static int unlock_futex_pi(u32 __user *uaddr, u32 uval)
        return 0;
 }
 
+/*
+ * Express the locking dependencies for lockdep:
+ */
+static inline void
+double_lock_hb(struct futex_hash_bucket *hb1, struct futex_hash_bucket *hb2)
+{
+       if (hb1 <= hb2) {
+               spin_lock(&hb1->lock);
+               if (hb1 < hb2)
+                       spin_lock_nested(&hb2->lock, SINGLE_DEPTH_NESTING);
+       } else { /* hb1 > hb2 */
+               spin_lock(&hb2->lock);
+               spin_lock_nested(&hb1->lock, SINGLE_DEPTH_NESTING);
+       }
+}
+
 /*
  * Wake up all waiters hashed on the physical page that is mapped
  * to this virtual address:
@@ -630,8 +646,10 @@ static int futex_wake(u32 __user *uaddr, int nr_wake)
 
        list_for_each_entry_safe(this, next, head, list) {
                if (match_futex (&this->key, &key)) {
-                       if (this->pi_state)
-                               return -EINVAL;
+                       if (this->pi_state) {
+                               ret = -EINVAL;
+                               break;
+                       }
                        wake_futex(this);
                        if (++ret >= nr_wake)
                                break;
@@ -672,11 +690,7 @@ retryfull:
        hb2 = hash_futex(&key2);
 
 retry:
-       if (hb1 < hb2)
-               spin_lock(&hb1->lock);
-       spin_lock(&hb2->lock);
-       if (hb1 > hb2)
-               spin_lock(&hb1->lock);
+       double_lock_hb(hb1, hb2);
 
        op_ret = futex_atomic_op_inuser(op, uaddr2);
        if (unlikely(op_ret < 0)) {
@@ -785,11 +799,7 @@ static int futex_requeue(u32 __user *uaddr1, u32 __user *uaddr2,
        hb1 = hash_futex(&key1);
        hb2 = hash_futex(&key2);
 
-       if (hb1 < hb2)
-               spin_lock(&hb1->lock);
-       spin_lock(&hb2->lock);
-       if (hb1 > hb2)
-               spin_lock(&hb1->lock);
+       double_lock_hb(hb1, hb2);
 
        if (likely(cmpval != NULL)) {
                u32 curval;
@@ -1208,7 +1218,7 @@ static int do_futex_lock_pi(u32 __user *uaddr, int detect, int trylock,
        }
 
        down_read(&curr->mm->mmap_sem);
-       hb = queue_lock(&q, -1, NULL);
+       spin_lock(q.lock_ptr);
 
        /*
         * Got the lock. We might not be the anticipated owner if we