[libcamera-devel] [PATCH v3 03/11] libcamera: request: Provide a sequence number

[Kieran Bingham]

Provide a sequence number on Requests which are added by the pipeline
handler.

Each pipeline handler keeps a requestSequence per CameraData and
increments everytime a request is queued on that camera.

The sequence number is associated with the Request and can be utilised
for assisting with debugging, and printing the queueing sequence of in
flight requests.

Signed-off-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
---
 include/libcamera/internal/pipeline_handler.h |  4 +++-
 include/libcamera/request.h                   |  2 ++
 src/libcamera/pipeline_handler.cpp            |  2 ++
 src/libcamera/request.cpp                     | 11 +++++++++--
 4 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/include/libcamera/internal/pipeline_handler.h b/include/libcamera/internal/pipeline_handler.h
index 6aca0b46f43d..9bdda8f3b799 100644
--- a/include/libcamera/internal/pipeline_handler.h
+++ b/include/libcamera/internal/pipeline_handler.h
@@ -38,7 +38,7 @@ class CameraData
 {
 public:
 	explicit CameraData(PipelineHandler *pipe)
-		: pipe_(pipe)
+		: pipe_(pipe), requestSequence_(0)
 	{
 	}
 	virtual ~CameraData() = default;
@@ -48,6 +48,8 @@ public:
 	ControlInfoMap controlInfo_;
 	ControlList properties_;
 
+	uint32_t requestSequence_;
+
 private:
 	LIBCAMERA_DISABLE_COPY(CameraData)
 };
diff --git a/include/libcamera/request.h b/include/libcamera/request.h
index 6e5aad5f6b75..cd5a24741f8a 100644
--- a/include/libcamera/request.h
+++ b/include/libcamera/request.h
@@ -50,6 +50,7 @@ public:
 	int addBuffer(const Stream *stream, FrameBuffer *buffer);
 	FrameBuffer *findBuffer(const Stream *stream) const;
 
+	uint32_t sequence() const { return sequence_; }
 	uint64_t cookie() const { return cookie_; }
 	Status status() const { return status_; }
 
@@ -71,6 +72,7 @@ private:
 	BufferMap bufferMap_;
 	std::unordered_set<FrameBuffer *> pending_;
 
+	uint32_t sequence_;
 	const uint64_t cookie_;
 	Status status_;
 	bool cancelled_;
diff --git a/src/libcamera/pipeline_handler.cpp b/src/libcamera/pipeline_handler.cpp
index d22991d318c9..e3d4975d9ffd 100644
--- a/src/libcamera/pipeline_handler.cpp
+++ b/src/libcamera/pipeline_handler.cpp
@@ -382,6 +382,8 @@ int PipelineHandler::queueRequest(Request *request)
 	CameraData *data = cameraData(camera);
 	data->queuedRequests_.push_back(request);
 
+	request->sequence_ = data->requestSequence_++;
+
 	int ret = queueRequestDevice(camera, request);
 	if (ret)
 		data->queuedRequests_.remove(request);
diff --git a/src/libcamera/request.cpp b/src/libcamera/request.cpp
index 3ad83f3b8418..fc16b148a599 100644
--- a/src/libcamera/request.cpp
+++ b/src/libcamera/request.cpp
@@ -72,8 +72,8 @@ LOG_DEFINE_CATEGORY(Request)
  *
  */
 Request::Request(Camera *camera, uint64_t cookie)
-	: camera_(camera), cookie_(cookie), status_(RequestPending),
-	  cancelled_(false)
+	: camera_(camera), sequence_(0), cookie_(cookie),
+	  status_(RequestPending), cancelled_(false)
 {
 	/**
 	 * \todo Should the Camera expose a validator instance, to avoid
@@ -126,6 +126,7 @@ void Request::reuse(ReuseFlag flags)
 		bufferMap_.clear();
 	}
 
+	sequence_ = 0;
 	status_ = RequestPending;
 	cancelled_ = false;
 
@@ -227,6 +228,12 @@ FrameBuffer *Request::findBuffer(const Stream *stream) const
  * \return The metadata associated with the request
  */
 
+/**
+ * \fn Request::sequence()
+ * \brief Retrieve the sequence number for the request
+ * \return The request sequence number
+ */
+
 /**
  * \fn Request::cookie()
  * \brief Retrieve the cookie set when the request was created
-- 
2.25.1