[SCSI] zfcp: add measurement data for average qdio queue utilisation

Provide measurement data for the utilisation of the QDIO outbound queue.
The additional value allows to calculate an average queue utilisation
by looking at the deltas per time unit. Needed for capacity planning.
It is up to user space to handle wrap-arounds of the 64 bit value.

The new counter neatly complements the existing counter for queue full
conditions. That is why, both statistics counter have been integrated.

Signed-off-by: Martin Peschke <mpeschke@linux.vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

drivers/s390/scsi/zfcp_sysfs.c

@@ -487,7 +487,8 @@ static ssize_t zfcp_sysfs_adapter_q_full_show(struct device *dev,
 	struct zfcp_adapter *adapter =
 		(struct zfcp_adapter *) scsi_host->hostdata[0];
 
-	return sprintf(buf, "%d\n", atomic_read(&adapter->qdio_outb_full));
+	return sprintf(buf, "%d %llu\n", atomic_read(&adapter->qdio_outb_full),
+		       (unsigned long long)adapter->req_q_util);
 }
 static DEVICE_ATTR(queue_full, S_IRUGO, zfcp_sysfs_adapter_q_full_show, NULL);