s390/qdio: fix statistics for 128 SBALs

Old code would only scan up to 127 SBALs at once. So the last statistics
bucket was set aside to count "discovered 127 SBALs with new work"
events.

But nowadays we allow to scan all 128 SBALs for Output Queues, and a
subsequent patch will introduce the same for Input Queues.
So fix up the accounting to use the last bucket only when all 128 SBALs
have been discovered with new work.

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.h b/drivers/s390/cio/qdio.h
index bb1c8402c67d81cdd3aee50ce04ca356064a02b2..7f0aa95585a4253c11473ea40a7f4c75b53fd6b3 100644 (file)
--- a/drivers/s390/cio/qdio.h
+++ b/drivers/s390/cio/qdio.h
@@ -166,11 +166,7 @@ struct qdio_dev_perf_stat {
 } ____cacheline_aligned;
 
 struct qdio_queue_perf_stat {
-       /*
-        * Sorted into order-2 buckets: 1, 2-3, 4-7, ... 64-127, 128.
-        * Since max. 127 SBALs are scanned reuse entry for 128 as queue full
-        * aka 127 SBALs found.
-        */
+       /* Sorted into order-2 buckets: 1, 2-3, 4-7, ... 64-127, 128. */
        unsigned int nr_sbals[8];
        unsigned int nr_sbal_error;
        unsigned int nr_sbal_nop;

diff --git a/drivers/s390/cio/qdio_debug.c b/drivers/s390/cio/qdio_debug.c
index da95c923d81a2e8946ba7b8d306b5f04db577a97..863d17c802ca12bb855626dfef960a8d1a13cf4a 100644 (file)
--- a/drivers/s390/cio/qdio_debug.c
+++ b/drivers/s390/cio/qdio_debug.c
@@ -165,7 +165,7 @@ static int qstat_show(struct seq_file *m, void *v)
        }
 
        seq_printf(m, "\n1          2..        4..        8..        "
-                  "16..       32..       64..       127\n");
+                  "16..       32..       64..       128\n");
        for (i = 0; i < ARRAY_SIZE(q->q_stats.nr_sbals); i++)
                seq_printf(m, "%-10u ", q->q_stats.nr_sbals[i]);
        seq_printf(m, "\nError      NOP        Total\n%-10u %-10u %-10u\n\n",

diff --git a/drivers/s390/cio/qdio_main.c b/drivers/s390/cio/qdio_main.c
index 0c919a11a46e0582aec1c6240dd58baa5d2b5cf2..d4c699773070f98f5d7b96f579d603cddfeec918 100644 (file)
--- a/drivers/s390/cio/qdio_main.c
+++ b/drivers/s390/cio/qdio_main.c
@@ -413,15 +413,8 @@ static inline void qdio_stop_polling(struct qdio_q *q)
 
 static inline void account_sbals(struct qdio_q *q, unsigned int count)
 {
-       int pos;
-
        q->q_stats.nr_sbal_total += count;
-       if (count == QDIO_MAX_BUFFERS_MASK) {
-               q->q_stats.nr_sbals[7]++;
-               return;
-       }
-       pos = ilog2(count);
-       q->q_stats.nr_sbals[pos]++;
+       q->q_stats.nr_sbals[ilog2(count)]++;
 }
 
 static void process_buffer_error(struct qdio_q *q, unsigned int start,