Camera: Add debug messages for camera latency
Log latency histogram of:
- processCaptureRequest call,
- dequeueBuffer call, and
- waiting time for handout count fall below max_buffers
Test: Camera CTS
Bug: 62651109
Change-Id: I5ee1cdb4139fa359f0887d6f6871884e28739340
diff --git a/services/camera/libcameraservice/utils/LatencyHistogram.h b/services/camera/libcameraservice/utils/LatencyHistogram.h
new file mode 100644
index 0000000..bfd9b1b
--- /dev/null
+++ b/services/camera/libcameraservice/utils/LatencyHistogram.h
@@ -0,0 +1,48 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ANDROID_SERVERS_CAMERA_LATENCY_HISTOGRAM_H_
+#define ANDROID_SERVERS_CAMERA_LATENCY_HISTOGRAM_H_
+
+#include <vector>
+
+#include <utils/Timers.h>
+#include <utils/Mutex.h>
+
+namespace android {
+
+// Histogram for camera latency characteristic
+class CameraLatencyHistogram {
+public:
+ CameraLatencyHistogram() = delete;
+ CameraLatencyHistogram(int32_t binSizeMs, int32_t binCount=10);
+ void add(nsecs_t start, nsecs_t end);
+ void reset();
+
+ void dump(int fd, const char* name) const;
+ void log(const char* format, ...);
+private:
+ int32_t mBinSizeMs;
+ int32_t mBinCount;
+ std::vector<int64_t> mBins;
+ uint64_t mTotalCount;
+
+ void formatHistogramText(String8& lineBins, String8& lineBinCounts) const;
+}; // class CameraLatencyHistogram
+
+}; // namespace android
+
+#endif // ANDROID_SERVERS_CAMERA_LATENCY_HISTOGRAM_H_