android: camera_metadata: Add functions for instrumenting resizing

Add utility functions to CameraMetadata to check if it has been resized,
and for outputting the actual entry and data count. This is meant to be
used to output information on resizing, to assist developers in
choosing proper initial sizes to avoid resizing. Also make CameraDevice
use these functions for static and result metadata.

Signed-off-by: Paul Elder <paul.elder@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Hirokazu Honda <hiroh@chromium.org>

3 files changed, 31 insertions, 1 deletions

diff --git a/src/android/camera_device.cpp b/src/android/camera_device.cpp
index dc0c8f5f..7fc4ddb0 100644
--- a/src/android/camera_device.cpp
+++ b/src/android/camera_device.cpp
@@ -1438,6 +1438,13 @@ const camera_metadata_t *CameraDevice::getStaticMetadata()
 		return nullptr;
 	}
 
+	if (staticMetadata_->resized()) {
+		auto [entryCount, dataCount] = staticMetadata_->usage();
+		LOG(HAL, Info)
+			<< "Static metadata resized: " << entryCount
+			<< " entries and " << dataCount << " bytes used";
+	}
+
 	return staticMetadata_->get();
 }
 
@@ -2316,5 +2323,12 @@ CameraDevice::getResultMetadata(const Camera3RequestDescriptor &descriptor) cons
 		LOG(HAL, Error) << "Failed to construct result metadata";
 	}
 
+	if (resultMetadata->resized()) {
+		auto [entryCount, dataCount] = resultMetadata->usage();
+		LOG(HAL, Info)
+			<< "Result metadata resized: " << entryCount
+			<< " entries and " << dataCount << " bytes used";
+	}
+
 	return resultMetadata;
 }
diff --git a/src/android/camera_metadata.cpp b/src/android/camera_metadata.cpp
index ebe43ba4..c7298d62 100644
--- a/src/android/camera_metadata.cpp
+++ b/src/android/camera_metadata.cpp
@@ -14,17 +14,19 @@ using namespace libcamera;
 LOG_DEFINE_CATEGORY(CameraMetadata)
 
 CameraMetadata::CameraMetadata()
-	: metadata_(nullptr), valid_(false)
+	: metadata_(nullptr), valid_(false), resized_(false)
 {
 }
 
 CameraMetadata::CameraMetadata(size_t entryCapacity, size_t dataCapacity)
+	: resized_(false)
 {
 	metadata_ = allocate_camera_metadata(entryCapacity, dataCapacity);
 	valid_ = metadata_ != nullptr;
 }
 
 CameraMetadata::CameraMetadata(const camera_metadata_t *metadata)
+	: resized_(false)
 {
 	metadata_ = clone_camera_metadata(metadata);
 	valid_ = metadata_ != nullptr;
@@ -55,6 +57,14 @@ CameraMetadata &CameraMetadata::operator=(const CameraMetadata &other)
 	return *this;
 }
 
+std::tuple<size_t, size_t> CameraMetadata::usage() const
+{
+	size_t currentEntryCount = get_camera_metadata_entry_count(metadata_);
+	size_t currentDataCount = get_camera_metadata_data_count(metadata_);
+
+	return { currentEntryCount, currentDataCount };
+}
+
 bool CameraMetadata::getEntry(uint32_t tag, camera_metadata_ro_entry_t *entry) const
 {
 	if (find_camera_metadata_ro_entry(metadata_, tag, entry))
@@ -104,6 +114,8 @@ bool CameraMetadata::resize(size_t count, size_t size)
 
 		append_camera_metadata(metadata_, oldMetadata);
 		free_camera_metadata(oldMetadata);
+
+		resized_ = true;
 	}
 
 	return true;
diff --git a/src/android/camera_metadata.h b/src/android/camera_metadata.h
index f8f2a0d2..3b7c9e24 100644
--- a/src/android/camera_metadata.h
+++ b/src/android/camera_metadata.h
@@ -23,6 +23,9 @@ public:
 
 	CameraMetadata &operator=(const CameraMetadata &other);
 
+	std::tuple<size_t, size_t> usage() const;
+	bool resized() const { return resized_; }
+
 	bool isValid() const { return valid_; }
 	bool getEntry(uint32_t tag, camera_metadata_ro_entry_t *entry) const;
 
@@ -89,6 +92,7 @@ private:
 
 	camera_metadata_t *metadata_;
 	bool valid_;
+	bool resized_;
 };
 
 #endif /* __ANDROID_CAMERA_METADATA_H__ */