s390/qdio: replace shift loop by ilog2

account_sbals is called by get_inbound_buffer_frontier and
get_outbound_buffer_frontier with 'count' value > 0 so we can safely
convert shift loop to ilog2.

Cc: Joe Perches <joe@perches.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 3 insertions, 4 deletions

diff --git a/drivers/s390/cio/qdio_main.c b/drivers/s390/cio/qdio_main.c
index 77466c4faabb..f5f42c431409 100644
--- a/drivers/s390/cio/qdio_main.c
+++ b/drivers/s390/cio/qdio_main.c
@@ -409,17 +409,16 @@ static inline void qdio_stop_polling(struct qdio_q *q)
                 set_buf_state(q, q->u.in.ack_start, SLSB_P_INPUT_NOT_INIT);
 }
 
-static inline void account_sbals(struct qdio_q *q, int count)
+static inline void account_sbals(struct qdio_q *q, unsigned int count)
 {
-        int pos = 0;
+        int pos;
 
         q->q_stats.nr_sbal_total += count;
         if (count == QDIO_MAX_BUFFERS_MASK) {
                 q->q_stats.nr_sbals[7]++;
                 return;
         }
-        while (count >>= 1)
-                pos++;
+        pos = ilog2(count);
         q->q_stats.nr_sbals[pos]++;
 }