async: fix __lowest_in_progress()
[~shefty/rdma-dev.git] / kernel / async.c
index a1d585c351d663f3cc64f0f874b0a38562797dc7..6f34904a0b5357ba84ae2e8eaa9188c67b1b09d4 100644 (file)
@@ -86,18 +86,27 @@ static atomic_t entry_count;
  */
 static async_cookie_t  __lowest_in_progress(struct async_domain *running)
 {
+       async_cookie_t first_running = next_cookie;     /* infinity value */
+       async_cookie_t first_pending = next_cookie;     /* ditto */
        struct async_entry *entry;
 
+       /*
+        * Both running and pending lists are sorted but not disjoint.
+        * Take the first cookies from both and return the min.
+        */
        if (!list_empty(&running->domain)) {
                entry = list_first_entry(&running->domain, typeof(*entry), list);
-               return entry->cookie;
+               first_running = entry->cookie;
        }
 
-       list_for_each_entry(entry, &async_pending, list)
-               if (entry->running == running)
-                       return entry->cookie;
+       list_for_each_entry(entry, &async_pending, list) {
+               if (entry->running == running) {
+                       first_pending = entry->cookie;
+                       break;
+               }
+       }
 
-       return next_cookie;     /* "infinity" value */
+       return min(first_running, first_pending);
 }
 
 static async_cookie_t  lowest_in_progress(struct async_domain *running)
@@ -118,13 +127,17 @@ static void async_run_entry_fn(struct work_struct *work)
 {
        struct async_entry *entry =
                container_of(work, struct async_entry, work);
+       struct async_entry *pos;
        unsigned long flags;
        ktime_t uninitialized_var(calltime), delta, rettime;
        struct async_domain *running = entry->running;
 
-       /* 1) move self to the running queue */
+       /* 1) move self to the running queue, make sure it stays sorted */
        spin_lock_irqsave(&async_lock, flags);
-       list_move_tail(&entry->list, &running->domain);
+       list_for_each_entry_reverse(pos, &running->domain, list)
+               if (entry->cookie < pos->cookie)
+                       break;
+       list_move_tail(&entry->list, &pos->list);
        spin_unlock_irqrestore(&async_lock, flags);
 
        /* 2) run (and print duration) */