[PATCH V3] dmaengine: dmatest: exclude compare and fill time during perf report

From: Sinan Kaya
Date: Thu Sep 01 2016 - 10:04:01 EST


Dmatest is currently including compare and fill time into the
calculated performance numbers. This does not reflect the HW
capability and the results vary based on the CPU speed instead of
the HW speed.

Signed-off-by: Sinan Kaya <okaya@xxxxxxxxxxxxxx>
---
drivers/dma/dmatest.c | 17 +++++++++++++++--
1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/drivers/dma/dmatest.c b/drivers/dma/dmatest.c
index 1245db5..738fbd1 100644
--- a/drivers/dma/dmatest.c
+++ b/drivers/dma/dmatest.c
@@ -426,7 +426,9 @@ static int dmatest_func(void *data)
int src_cnt;
int dst_cnt;
int i;
- ktime_t ktime;
+ ktime_t ktime, start, diff;
+ ktime_t filltime = ktime_set(0, 0);
+ ktime_t comparetime = ktime_set(0, 0);
s64 runtime = 0;
unsigned long long total_len = 0;

@@ -531,6 +533,7 @@ static int dmatest_func(void *data)
src_off = 0;
dst_off = 0;
} else {
+ start = ktime_get();
src_off = dmatest_random() % (params->buf_size - len + 1);
dst_off = dmatest_random() % (params->buf_size - len + 1);

@@ -541,6 +544,9 @@ static int dmatest_func(void *data)
params->buf_size);
dmatest_init_dsts(thread->dsts, dst_off, len,
params->buf_size);
+
+ diff = ktime_sub(ktime_get(), start);
+ filltime = ktime_add(filltime, diff);
}

um = dmaengine_get_unmap_data(dev->dev, src_cnt+dst_cnt,
@@ -683,6 +689,7 @@ static int dmatest_func(void *data)
continue;
}

+ start = ktime_get();
pr_debug("%s: verifying source buffer...\n", current->comm);
error_count = dmatest_verify(thread->srcs, 0, src_off,
0, PATTERN_SRC, true);
@@ -703,6 +710,9 @@ static int dmatest_func(void *data)
params->buf_size, dst_off + len,
PATTERN_DST, false);

+ diff = ktime_sub(ktime_get(), start);
+ comparetime = ktime_add(comparetime, diff);
+
if (error_count) {
result("data error", total_tests, src_off, dst_off,
len, error_count);
@@ -712,7 +722,10 @@ static int dmatest_func(void *data)
dst_off, len, 0);
}
}
- runtime = ktime_us_delta(ktime_get(), ktime);
+ ktime = ktime_sub(ktime_get(), ktime);
+ ktime = ktime_sub(ktime, comparetime);
+ ktime = ktime_sub(ktime, filltime);
+ runtime = ktime_to_us(ktime);

ret = 0;
err_dstbuf:
--
1.9.1