Merge branch 'timers-for-linus-clocksource' of git://git.kernel.org/pub/scm/linux...

[safe/jmp/linux-2.6] / kernel / futex.c

diff --git a/kernel/futex.c b/kernel/futex.c
index 381125a..80b5ce7 100644 (file)
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -1507,7 +1507,6 @@ handle_fault:
 #define FLAGS_HAS_TIMEOUT      0x04
 
 static long futex_wait_restart(struct restart_block *restart);
-static long futex_lock_pi_restart(struct restart_block *restart);
 
 /**
  * fixup_owner() - Post lock pi_state and corner case management
@@ -1930,21 +1929,6 @@ uaddr_faulted:
        goto retry;
 }
 
-static long futex_lock_pi_restart(struct restart_block *restart)
-{
-       u32 __user *uaddr = (u32 __user *)restart->futex.uaddr;
-       ktime_t t, *tp = NULL;
-       int fshared = restart->futex.flags & FLAGS_SHARED;
-
-       if (restart->futex.flags & FLAGS_HAS_TIMEOUT) {
-               t.tv64 = restart->futex.time;
-               tp = &t;
-       }
-       restart->fn = do_no_restart_syscall;
-
-       return (long)futex_lock_pi(uaddr, fshared, restart->futex.val, tp, 0);
-}
-
 /*
  * Userspace attempted a TID -> 0 atomic transition, and failed.
  * This is the in-kernel slowpath: we look up the PI state (if any),
@@ -2060,7 +2044,7 @@ pi_faulted:
  *
  * Returns
  *  0 - no early wakeup detected
- * <0 - -ETIMEDOUT or -ERESTARTSYS (FIXME: or ERESTARTNOINTR?)
+ * <0 - -ETIMEDOUT or -ERESTARTNOINTR
  */
 static inline
 int handle_early_requeue_pi_wakeup(struct futex_hash_bucket *hb,
@@ -2087,15 +2071,8 @@ int handle_early_requeue_pi_wakeup(struct futex_hash_bucket *hb,
 
                if (timeout && !timeout->task)
                        ret = -ETIMEDOUT;
-               else {
-                       /*
-                        * We expect signal_pending(current), but another
-                        * thread may have handled it for us already.
-                        */
-                       /* FIXME: ERESTARTSYS or ERESTARTNOINTR?  Do we care if
-                        * the user specified SA_RESTART or not? */
-                       ret = -ERESTARTSYS;
-               }
+               else
+                       ret = -ERESTARTNOINTR;
        }
        return ret;
 }
@@ -2148,12 +2125,10 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, int fshared,
        struct hrtimer_sleeper timeout, *to = NULL;
        struct rt_mutex_waiter rt_waiter;
        struct rt_mutex *pi_mutex = NULL;
-       struct restart_block *restart;
        struct futex_hash_bucket *hb;
        union futex_key key2;
        struct futex_q q;
        int res, ret;
-       u32 uval;
 
        if (!bitset)
                return -EINVAL;
@@ -2252,30 +2227,17 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, int fshared,
                if (rt_mutex_owner(pi_mutex) == current)
                        rt_mutex_unlock(pi_mutex);
        } else if (ret == -EINTR) {
-               ret = -EFAULT;
-               if (get_user(uval, uaddr2))
-                       goto out_put_keys;
-
                /*
-                * We've already been requeued, so restart by calling
-                * futex_lock_pi() directly, rather then returning to this
-                * function.
+                * We've already been requeued, but we have no way to
+                * restart by calling futex_lock_pi() directly. We
+                * could restart the syscall, but that will look at
+                * the user space value and return right away. So we
+                * drop back with EWOULDBLOCK to tell user space that
+                * "val" has been changed. That's the same what the
+                * restart of the syscall would do in
+                * futex_wait_setup().
                 */
-               ret = -ERESTART_RESTARTBLOCK;
-               restart = &current_thread_info()->restart_block;
-               restart->fn = futex_lock_pi_restart;
-               restart->futex.uaddr = (u32 *)uaddr2;
-               restart->futex.val = uval;
-               restart->futex.flags = 0;
-               if (abs_time) {
-                       restart->futex.flags |= FLAGS_HAS_TIMEOUT;
-                       restart->futex.time = abs_time->tv64;
-               }
-
-               if (fshared)
-                       restart->futex.flags |= FLAGS_SHARED;
-               if (clockrt)
-                       restart->futex.flags |= FLAGS_CLOCKRT;
+               ret = -EWOULDBLOCK;
        }
 
 out_put_keys: