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Date: Thu, 17 Jan 2013 07:32:32 +0100
From: Luigi Rizzo <rizzo@iet.unipi.it>
To: Jack Vogel <jfvogel@gmail.com>
Subject: Re: two problems in dev/e1000/if_lem.c::lem_handle_rxtx()
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On Tue, Jan 15, 2013 at 09:43:54PM -0800, Jack Vogel wrote:
> OK, will look at this as soon as I can.
> 
> Jack

below is a short patch that reschedule the task if the queue
has not been drained. Tested on qemu. I can do the commit if you like.

cheers
luigi

Index: ../head/sys/dev/e1000/if_lem.c
===================================================================
--- ../head/sys/dev/e1000/if_lem.c	(revision 245218)
+++ ../head/sys/dev/e1000/if_lem.c	(working copy)
@@ -1337,12 +1411,16 @@
 
 
 	if (ifp->if_drv_flags & IFF_DRV_RUNNING) {
-		lem_rxeof(adapter, adapter->rx_process_limit, NULL);
+		bool more = lem_rxeof(adapter, adapter->rx_process_limit, NULL);
 		EM_TX_LOCK(adapter);
 		lem_txeof(adapter);
 		if (!IFQ_DRV_IS_EMPTY(&ifp->if_snd))
 			lem_start_locked(ifp);
 		EM_TX_UNLOCK(adapter);
+		if (more) {
+			taskqueue_enqueue(adapter->tq, &adapter->rxtx_task);
+			return;
+		}
 	}
 
 	if (ifp->if_drv_flags & IFF_DRV_RUNNING)