Use fixed point division to calculate iops to prevent reporting 0 iops
when operations last for longer than a second.
Signed-off-by: Seraj Alijan <seraj.alijan@xxxxxxxxxxx>
---
drivers/dma/dmatest.c | 17 ++++++++++++++---
1 file changed, 14 insertions(+), 3 deletions(-)
diff --git a/drivers/dma/dmatest.c b/drivers/dma/dmatest.c
index d192772..998344b 100644
--- a/drivers/dma/dmatest.c
+++ b/drivers/dma/dmatest.c
@@ -177,6 +177,13 @@ MODULE_PARM_DESC(test_list, "Print current test list");
#define PATTERN_COUNT_MASK 0x1f
#define PATTERN_MEMSET_IDX 0x01
+/* Fixed point arithmetic ops */
+#define FIXPT_SHIFT 8
+#define FIXPNT_MASK 0xFF
+#define FIXPT_TO_INT(a) ((a) >> FIXPT_SHIFT)
+#define INT_TO_FIXPT(a) ((a) << FIXPT_SHIFT)
+#define FIXPT_GET_FRAC(a) ((((a) & FIXPNT_MASK) * 100) >> FIXPT_SHIFT)
+
/* poor man's completion - we want to use wait_event_freezable() on it */
struct dmatest_done {
bool done;
@@ -453,13 +460,15 @@ static unsigned long long dmatest_persec(s64 runtime, unsigned int val)
}
per_sec *= val;
+ per_sec = INT_TO_FIXPT(per_sec);
do_div(per_sec, runtime);
+
return per_sec;
}
static unsigned long long dmatest_KBs(s64 runtime, unsigned long long len)
{
- return dmatest_persec(runtime, len >> 10);
+ return FIXPT_TO_INT(dmatest_persec(runtime, len >> 10));
}
/*
@@ -500,6 +509,7 @@ static int dmatest_func(void *data)
ktime_t comparetime = 0;
s64 runtime = 0;
unsigned long long total_len = 0;
+ unsigned long long iops = 0;
u8 align = 0;
bool is_memset = false;
dma_addr_t *srcs;
@@ -838,9 +848,10 @@ static int dmatest_func(void *data)
err_free_coefs:
kfree(pq_coefs);
err_thread_type:
- pr_info("%s: summary %u tests, %u failures %llu iops %llu KB/s (%d)\n",
+ iops = dmatest_persec(runtime, total_tests);
+ pr_info("%s: summary %u tests, %u failures %llu.%02llu iops %llu KB/s (%d)\n",
current->comm, total_tests, failed_tests,
- dmatest_persec(runtime, total_tests),
+ FIXPT_TO_INT(iops), FIXPT_GET_FRAC(iops),
dmatest_KBs(runtime, total_len), ret);
/* terminate all transfers on specified channels */
--
2.7.4
