[libcamera-devel] [PATCH v1 5/5] cam: Move request processing to main thread

[Kieran Bingham]

On 13/11/2020 06:38, Laurent Pinchart wrote:
> The request completion handler is invoked in the camera manager thread,
> which shouldn't be blocked for large amounts of time. As writing the
> frames to disk can be a time-consuming process, move request processing
> to the main thread by queueing an event to the event loop.
> 
> Signed-off-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>

Reviewed-by: Kieran Bingham <kieran.bingham at ideasonboard.com>

> ---
>  src/cam/capture.cpp | 9 +++++++++
>  src/cam/capture.h   | 1 +
>  2 files changed, 10 insertions(+)
> 
> diff --git a/src/cam/capture.cpp b/src/cam/capture.cpp
> index 7580f798288c..43b109d099f6 100644
> --- a/src/cam/capture.cpp
> +++ b/src/cam/capture.cpp
> @@ -157,6 +157,15 @@ void Capture::requestComplete(Request *request)
>  	if (request->status() == Request::RequestCancelled)
>  		return;
>  
> +	/*
> +	 * Defer processing of the completed request to the event loop, to avoid
> +	 * blocking the camera manager thread.
> +	 */
> +	loop_->callLater(std::bind(&Capture::processRequest, this, request));
> +}
> +
> +void Capture::processRequest(Request *request)
> +{
>  	const Request::BufferMap &buffers = request->buffers();
>  
>  	/*
> diff --git a/src/cam/capture.h b/src/cam/capture.h
> index 45e5e8a9ba27..d21c95a26ce7 100644
> --- a/src/cam/capture.h
> +++ b/src/cam/capture.h
> @@ -33,6 +33,7 @@ private:
>  	int capture(libcamera::FrameBufferAllocator *allocator);
>  
>  	void requestComplete(libcamera::Request *request);
> +	void processRequest(libcamera::Request *request);
>  
>  	std::shared_ptr<libcamera::Camera> camera_;
>  	libcamera::CameraConfiguration *config_;
> 

-- 
Regards
--
Kieran