[S390] qdio: add timestamp for last queue scan time

Add a timestamp per queue and update the timestamp when the queue is
scanned. Add the queue timestamps and the timestamp of the last
adapter interrupt to the debugfs output. The timestamps are useful
for debugging stall conditions.

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/cio/qdio_main.c b/drivers/s390/cio/qdio_main.c
index 7ded1b2..a76d676 100644
--- a/drivers/s390/cio/qdio_main.c
+++ b/drivers/s390/cio/qdio_main.c
@@ -512,6 +512,8 @@
 	int count, stop;
 	unsigned char state = 0;
 
+	q->timestamp = get_clock_fast();
+
 	/*
 	 * Don't check 128 buffers, as otherwise qdio_inbound_q_moved
 	 * would return 0.
@@ -781,6 +783,8 @@
 	int count, stop;
 	unsigned char state = 0;
 
+	q->timestamp = get_clock_fast();
+
 	if (need_siga_sync(q))
 		if (((queue_type(q) != QDIO_IQDIO_QFMT) &&
 		    !pci_out_supported(q)) ||