From 411987838ef6c141cc6e0ed2713cb06600855df8 Mon Sep 17 00:00:00 2001 From: Laurent Pinchart Date: Tue, 12 Oct 2021 05:15:22 +0300 Subject: cam: Drop frames once the capture limit is reached The camera session keeps requeuing requests until the capture limit is reached. This causes more request than the limit to complete, as there's a queue of requests in flight. When capturing from multiple cameras concurrently, this results in the captureDone signal being emitted for every request completion after the limit is reached, instead of once per camera session when reaching the limit. Fix this by simply dropping any request that completes after the limit is reached. We could instead avoid requeuing more requests than needed to reach the limit, but that may cause request starvation in pipelines, which are currently not handled consistently (or correctly). Signed-off-by: Laurent Pinchart Reviewed-by: Kieran Bingham --- src/cam/camera_session.cpp | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/src/cam/camera_session.cpp b/src/cam/camera_session.cpp index 60501827..1bf460fa 100644 --- a/src/cam/camera_session.cpp +++ b/src/cam/camera_session.cpp @@ -346,6 +346,16 @@ void CameraSession::requestComplete(Request *request) void CameraSession::processRequest(Request *request) { + /* + * If we've reached the capture limit, we're done. This doesn't + * duplicate the check below that emits the captureDone signal, as this + * function will be called for each request still in flight after the + * capture limit is reached and we don't want to emit the signal every + * single time. + */ + if (captureLimit_ && captureCount_ >= captureLimit_) + return; + const Request::BufferMap &buffers = request->buffers(); /* @@ -398,6 +408,10 @@ void CameraSession::processRequest(Request *request) } } + /* + * Notify the user that capture is complete if the limit has just been + * reached. + */ captureCount_++; if (captureLimit_ && captureCount_ >= captureLimit_) { captureDone.emit(); -- cgit v1.2.1