io_free_req(req);
}
+static unsigned io_cqring_events(struct io_cq_ring *ring)
+{
+ /* See comment at the top of this file */
+ smp_rmb();
+ return READ_ONCE(ring->r.tail) - READ_ONCE(ring->r.head);
+}
+
/*
* Find and free completed poll iocbs
*/
do {
int tmin = 0;
+ /*
+ * Don't enter poll loop if we already have events pending.
+ * If we do, we can potentially be spinning for commands that
+ * already triggered a CQE (eg in error).
+ */
+ if (io_cqring_events(ctx->cq_ring))
+ break;
+
/*
* If a submit got punted to a workqueue, we can have the
* application entering polling for a command before it gets
return submit;
}
-static unsigned io_cqring_events(struct io_cq_ring *ring)
-{
- /* See comment at the top of this file */
- smp_rmb();
- return READ_ONCE(ring->r.tail) - READ_ONCE(ring->r.head);
-}
-
/*
* Wait until events become available, if we don't already have some. The
* application must reap them itself, as they reside on the shared cq ring.