1 files changed, 34 insertions, 1 deletions

diff --git a/litmus/locking.c b/litmus/locking.c
index 58b5edd9df32..f7d33156cf49 100644
--- a/litmus/locking.c
+++ b/litmus/locking.c
@@ -246,6 +246,11 @@ void select_next_lock(dgl_wait_state_t* dgl_wait /*, struct litmus_lock* prev_lo
 
         //WARN_ON(dgl_wait->locks[dgl_wait->last_primary] != prev_lock);
 
+        if (dgl_wait->last_primary == 0) {
+                /* loop around */
+                dgl_wait->last_primary = dgl_wait->size;
+        }
+        
         // note reverse order
         for(dgl_wait->last_primary = dgl_wait->last_primary - 1;
                 dgl_wait->last_primary >= 0;
@@ -327,6 +332,35 @@ static void snprintf_dgl(char* buf, size_t bsz, struct litmus_lock* dgl_locks[],
 }
 #endif
 
+
+/* only valid when locks are prioq locks!!!
+ * THE BIG DGL LOCK MUST BE HELD! */
+int __attempt_atomic_dgl_acquire(struct litmus_lock *cur_lock, dgl_wait_state_t *dgl_wait)
+{
+        int i;
+
+        /* check to see if we can take all the locks */
+        for(i = 0; i < dgl_wait->size; ++i) {
+                struct litmus_lock *l = dgl_wait->locks[i];
+                if(!l->ops->dgl_can_quick_lock(l, dgl_wait->task))
+                {
+                        return -1;
+                }
+        }
+        
+        /* take the locks */
+        for(i = 0; i < dgl_wait->size; ++i) {
+                struct litmus_lock *l = dgl_wait->locks[i];
+                
+                l->ops->dgl_quick_lock(l, cur_lock, dgl_wait->task, &dgl_wait->wq_nodes[i]);
+                
+                BUG_ON(dgl_wait->task != *(l->nest.owner_ptr));
+        }
+        
+        return 0; /* success */
+}
+
+
 static long do_litmus_dgl_lock(dgl_wait_state_t *dgl_wait)
 {
         int i;
@@ -394,7 +428,6 @@ static long do_litmus_dgl_lock(dgl_wait_state_t *dgl_wait)
                                 raw_spin_unlock_irqrestore(dgl_lock, irqflags);  // free dgl_lock before suspending
 
                                 suspend_for_lock(); // suspend!!!
-                                //schedule();  // suspend!!!
 
                                 TS_DGL_LOCK_RESUME;