s390/qdio: allow to scan all 128 Input SBALs

The comment is inaccurate, qdio_inbound_q_moved() and/or its callers no
longer get confused by a count of 128 completed SBALs.

Scanning all 128 SBALs at once can improve IRQ reduction (as we now
place the ACK at the right spot), and reduce the amount of processing
needed to handle all completed SBALs.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

diff --git a/drivers/s390/cio/qdio_main.c b/drivers/s390/cio/qdio_main.c
index d4c699773070f98f5d7b96f579d603cddfeec918..0c1f186c629130a4516463b2c77b678ed8874fd9 100644 (file)
--- a/drivers/s390/cio/qdio_main.c
+++ b/drivers/s390/cio/qdio_main.c
@@ -457,11 +457,7 @@ static int get_inbound_buffer_frontier(struct qdio_q *q, unsigned int start)
 
        q->timestamp = get_tod_clock_fast();
 
-       /*
-        * Don't check 128 buffers, as otherwise qdio_inbound_q_moved
-        * would return 0.
-        */
-       count = min(atomic_read(&q->nr_buf_used), QDIO_MAX_BUFFERS_MASK);
+       count = atomic_read(&q->nr_buf_used);
        if (!count)
                return 0;