From: Hans-Joachim Picht <hpicht@redhat.com>
Subject: [RHEL5.1 PATCH] qdio: Refresh buffer states for IQDIO Asynchronous 	output queue
Date: Tue, 11 Sep 2007 17:53:28 +0200
Bugzilla: 222181
Message-Id: <1189526008.30755.4.camel@localhost.localdomain>
Changelog: [s390] qdio: Refresh buffer states for IQDIO Asynch output queue


Problem:
=========
If iptables is running and qeth devices are active, shutdown/reboot 
hangs.

Bugzilla
=========

BZ 222181
https://bugzilla.redhat.com/show_bug.cgi?id=222181

Description:
============

Hipersocket Multicast queue works asynchronously. When sending buffers,
the buffer state change may happen delayed. The tasklet for checking
changes in the outbound queue excluded IQDIO async queues from this
process. This created either a hang situation when the queue ran full,
or presented a hang situation at interface close time.
The tasklet processing is changed to include IQDIO async queues when
requesting buffer state refresh.

Upstream status of the patch:
=============================
linux-2.6 git

Test status:
============
Kernel with patch was built and successfully tested


Please ACK.

With best regards,

        Hans

diff -Nupr linux-rhel5/drivers/s390/cio/qdio.c linux-rhel5-patched/drivers/s390/cio/qdio.c
--- linux-rhel5/drivers/s390/cio/qdio.c	2007-09-10 10:28:33.000000000 +0200
+++ linux-rhel5-patched/drivers/s390/cio/qdio.c	2007-09-10 10:30:59.000000000 +0200
@@ -739,7 +739,8 @@ qdio_get_outbound_buffer_frontier(struct
 	first_not_to_check=f+qdio_min(atomic_read(&q->number_of_buffers_used),
 				      (QDIO_MAX_BUFFERS_PER_Q-1));
 
-	if ((!q->is_iqdio_q)&&(!q->hydra_gives_outbound_pcis))
+	if (((!q->is_iqdio_q)&&(!q->hydra_gives_outbound_pcis)) ||
+	    (q->queue_type == QDIO_IQDIO_QFMT_ASYNCH))
 		SYNC_MEMORY;
 
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