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

Sinan Kaya okaya at codeaurora.org
Thu Sep 1 07:02:55 PDT 2016


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 at codeaurora.org>
---
 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




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