greybus: Revert "gb_loopback: Fix throughput calculations"

This reverts commit 9b9b046af237f5674c2f7ca991dc62332b2d4041

Bryan wants more feedback first.
Reported-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

drivers/staging/greybus/loopback.c

@@ -81,7 +81,6 @@ struct gb_loopback {
 	atomic_t outstanding_operations;
 
 	/* Per connection stats */
-	struct timeval ts;
 	struct gb_loopback_stats latency;
 	struct gb_loopback_stats throughput;
 	struct gb_loopback_stats requests_per_second;
@@ -521,6 +520,7 @@ static void gb_loopback_async_operation_callback(struct gb_operation *operation)
 		gb_loopback_push_latency_ts(gb, &op_async->ts, &te);
 		gb->elapsed_nsecs = gb_loopback_calc_latency(&op_async->ts,
 							     &te);
+		gb_loopback_calculate_stats(gb);
 	}
 
 	if (op_async->pending) {
@@ -529,7 +529,6 @@ static void gb_loopback_async_operation_callback(struct gb_operation *operation)
 		del_timer_sync(&op_async->timer);
 		gb_loopback_async_operation_put(op_async);
 	}
-	gb_loopback_calculate_stats(gb);
 	mutex_unlock(&gb->mutex);
 
 	dev_dbg(&gb->connection->bundle->dev, "complete operation %d\n",
@@ -847,7 +846,6 @@ static void gb_loopback_reset_stats(struct gb_loopback *gb)
 	/* Should be initialized at least once per transaction set */
 	gb->apbridge_latency_ts = 0;
 	gb->gpbridge_latency_ts = 0;
-	memset(&gb->ts, 0, sizeof(struct timeval));
 }
 
 static void gb_loopback_update_stats(struct gb_loopback_stats *stats, u32 val)
@@ -862,15 +860,15 @@ static void gb_loopback_update_stats(struct gb_loopback_stats *stats, u32 val)
 
 static void gb_loopback_requests_update(struct gb_loopback *gb, u32 latency)
 {
-	u64 req = gb->requests_completed * USEC_PER_SEC;
+	u32 req = USEC_PER_SEC;
 
 	do_div(req, latency);
-	gb_loopback_update_stats(&gb->requests_per_second, (u32)req);
+	gb_loopback_update_stats(&gb->requests_per_second, req);
 }
 
 static void gb_loopback_throughput_update(struct gb_loopback *gb, u32 latency)
 {
-	u64 throughput;
+	u32 throughput;
 	u32 aggregate_size = sizeof(struct gb_operation_msg_hdr) * 2;
 
 	switch (gb->type) {
@@ -889,13 +887,14 @@ static void gb_loopback_throughput_update(struct gb_loopback *gb, u32 latency)
 		return;
 	}
 
-	aggregate_size *= gb->requests_completed;
-	throughput = aggregate_size * USEC_PER_SEC;
+	/* Calculate bytes per second */
+	throughput = USEC_PER_SEC;
 	do_div(throughput, latency);
-	gb_loopback_update_stats(&gb->throughput, (u32)throughput);
+	throughput *= aggregate_size;
+	gb_loopback_update_stats(&gb->throughput, throughput);
 }
 
-static void gb_loopback_calculate_latency_stats(struct gb_loopback *gb)
+static void gb_loopback_calculate_stats(struct gb_loopback *gb)
 {
 	u32 lat;
 
@@ -908,6 +907,10 @@ static void gb_loopback_calculate_latency_stats(struct gb_loopback *gb)
 	/* Raw latency log on a per thread basis */
 	kfifo_in(&gb->kfifo_lat, (unsigned char *)&lat, sizeof(lat));
 
+	/* Log throughput and requests using latency as benchmark */
+	gb_loopback_throughput_update(gb, lat);
+	gb_loopback_requests_update(gb, lat);
+
 	/* Log the firmware supplied latency values */
 	gb_loopback_update_stats(&gb->apbridge_unipro_latency,
 				 gb->apbridge_latency_ts);
@@ -915,27 +918,6 @@ static void gb_loopback_calculate_latency_stats(struct gb_loopback *gb)
 				 gb->gpbridge_latency_ts);
 }
 
-static void gb_loopback_calculate_stats(struct gb_loopback *gb)
-{
-	u64 nlat;
-	u32 lat;
-	struct timeval te;
-
-	gb_loopback_calculate_latency_stats(gb);
-
-	if (gb->iteration_count == gb->iteration_max) {
-		do_gettimeofday(&te);
-		nlat = gb_loopback_calc_latency(&gb->ts, &te);
-		lat = gb_loopback_nsec_to_usec_latency(nlat);
-
-		gb_loopback_throughput_update(gb, lat);
-		gb_loopback_requests_update(gb, lat);
-
-		memset(&gb->ts, 0, sizeof(struct timeval));
-		gb->type = 0;
-	}
-}
-
 static void gb_loopback_async_wait_to_send(struct gb_loopback *gb)
 {
 	if (!(gb->async && gb->outstanding_operations_max))
@@ -973,10 +955,8 @@ static int gb_loopback_fn(void *data)
 
 		/* Optionally terminate */
 		if (send_count == gb->iteration_max) {
-			if (!gb->async)
-				send_count = 0;
-			else if (gb->iteration_count == gb->iteration_max)
-				send_count = 0;
+			gb->type = 0;
+			send_count = 0;
 			mutex_unlock(&gb->mutex);
 			continue;
 		}
@@ -985,15 +965,10 @@ static int gb_loopback_fn(void *data)
 		type = gb->type;
 		mutex_unlock(&gb->mutex);
 
-		if (gb->ts.tv_usec == 0 && gb->ts.tv_sec == 0)
-			do_gettimeofday(&gb->ts);
-
 		/* Else operations to perform */
 		if (gb->async) {
 			if (type == GB_LOOPBACK_TYPE_PING) {
 				error = gb_loopback_async_ping(gb);
-				if (!error)
-					gb->requests_completed++;
 				gb_loopback_calculate_stats(gb);
 			} else if (type == GB_LOOPBACK_TYPE_TRANSFER) {
 				error = gb_loopback_async_transfer(gb, size);
@@ -1014,8 +989,6 @@ static int gb_loopback_fn(void *data)
 
 			if (error)
 				gb->error++;
-			else
-				gb->requests_completed++;
 			gb->iteration_count++;
 			gb_loopback_calculate_stats(gb);
 		}