| Message ID | 20241008150916.1041703-1-mzamazal@redhat.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series |
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| Related | show |
Quoting Milan Zamazal (2024-10-08 16:09:16) > PipelineHandler::stop() calls stopDevice() method to perform pipeline > specific cleanup and then completes waiting requests. If any queued > requests remain, an assertion error is raised. > > Software ISP stores request buffers in > SimpleCameraData::conversionQueue_ and queues them as V4L2 signals > bufferReady. stopDevice() cleanup forgets to clean up the buffers and > their requests from conversionQueue_, possibly resulting in the > assertion error. This patch fixes the omission. > > The problem wasn't very visible when > SimplePipelineHandler::kNumInternalBuffers (the number of buffers > allocated in V4L2) was equal to the number of buffers exported from > software ISP. But when the number of the exported buffers was increased > by one in commit abe2ec64f9e4e97bbdfe3a50372611bd7b5315c2, the assertion > error started pop up in some environments. Increasing the number of the > buffers much more, e.g. to 9, makes the problem very reproducible. > > Each pipeline uses its own mechanism to track the requests to clean up > and it can't be excluded that similar omissions are present in other > places. But there is no obvious way to make a common cleanup for all > the pipelines (except for doing it instead of raising the assertion > error, which is probably undesirable, in order not to hide incomplete > pipeline specific cleanups). Indeed, I think that's why I added the assertion to make sure we force Pipeline handlers to do 'the right thing for that handler'. Maybe we could relax that in the future if it becomes apparetnly safe ... but I think this patch is probably the right direction for now. > > Bug: https://bugs.libcamera.org/show_bug.cgi?id=234 > Signed-off-by: Milan Zamazal <mzamazal@redhat.com> > --- > src/libcamera/pipeline/simple/simple.cpp | 15 +++++++++++++++ > 1 file changed, 15 insertions(+) > > diff --git a/src/libcamera/pipeline/simple/simple.cpp b/src/libcamera/pipeline/simple/simple.cpp > index 3ddce71d3..4e8504922 100644 > --- a/src/libcamera/pipeline/simple/simple.cpp > +++ b/src/libcamera/pipeline/simple/simple.cpp > @@ -284,6 +284,7 @@ public: > std::vector<std::unique_ptr<FrameBuffer>> conversionBuffers_; > std::queue<std::map<const Stream *, FrameBuffer *>> conversionQueue_; > bool useConversion_; > + void clearIncompleteRequests(); > > std::unique_ptr<Converter> converter_; > std::unique_ptr<SoftwareIsp> swIsp_; > @@ -897,6 +898,19 @@ void SimpleCameraData::conversionOutputDone(FrameBuffer *buffer) > pipe->completeRequest(request); > } > > +void SimpleCameraData::clearIncompleteRequests() > +{ > + while (!conversionQueue_.empty()) { > + for (auto &item : conversionQueue_.front()) { > + FrameBuffer *outputBuffer = item.second; > + Request *request = outputBuffer->request(); I think somewhere here we should be marking the buffers as cancelled before we complete it: outputBuffer->_d()->cancel(); > + pipe()->completeBuffer(request, outputBuffer); > + pipe()->completeRequest(request); in fact both those lines might be better as: request->_d()->cancel(); pipe()->completeRequest(request); as I think request->_d()->cancel(); will correctly mark all buffers as cancelled, and the request itself. With that handled, and retested: Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com> > + } > + conversionQueue_.pop(); > + } > +} > + > void SimpleCameraData::ispStatsReady(uint32_t frame, uint32_t bufferId) > { > swIsp_->processStats(frame, bufferId, > @@ -1407,6 +1421,7 @@ void SimplePipelineHandler::stopDevice(Camera *camera) > video->bufferReady.disconnect(data, &SimpleCameraData::bufferReady); > > data->conversionBuffers_.clear(); > + data->clearIncompleteRequests(); > > releasePipeline(data); > } > -- > 2.44.1 >
Hey, thanks a lot for the patch! I gave it a quick try on my Pixel 3a and while the revision here avoids the assertion most of the time and makes things much more stable, I still managed to trigger it with enough trying (4 buffers, starting/stopping/switching cameras in Gnome Snapshot). I haven't tried the suggestion from Kieran yet, but to me it looks like Stop() is currently still somehow racy - at least the way it's used by Pipewire. Regards On 08.10.24 17:09, Milan Zamazal wrote: > PipelineHandler::stop() calls stopDevice() method to perform pipeline > specific cleanup and then completes waiting requests. If any queued > requests remain, an assertion error is raised. > > Software ISP stores request buffers in > SimpleCameraData::conversionQueue_ and queues them as V4L2 signals > bufferReady. stopDevice() cleanup forgets to clean up the buffers and > their requests from conversionQueue_, possibly resulting in the > assertion error. This patch fixes the omission. > > The problem wasn't very visible when > SimplePipelineHandler::kNumInternalBuffers (the number of buffers > allocated in V4L2) was equal to the number of buffers exported from > software ISP. But when the number of the exported buffers was increased > by one in commit abe2ec64f9e4e97bbdfe3a50372611bd7b5315c2, the assertion > error started pop up in some environments. Increasing the number of the > buffers much more, e.g. to 9, makes the problem very reproducible. > > Each pipeline uses its own mechanism to track the requests to clean up > and it can't be excluded that similar omissions are present in other > places. But there is no obvious way to make a common cleanup for all > the pipelines (except for doing it instead of raising the assertion > error, which is probably undesirable, in order not to hide incomplete > pipeline specific cleanups). > > Bug: https://bugs.libcamera.org/show_bug.cgi?id=234 > Signed-off-by: Milan Zamazal <mzamazal@redhat.com> > --- > src/libcamera/pipeline/simple/simple.cpp | 15 +++++++++++++++ > 1 file changed, 15 insertions(+) > > diff --git a/src/libcamera/pipeline/simple/simple.cpp b/src/libcamera/pipeline/simple/simple.cpp > index 3ddce71d3..4e8504922 100644 > --- a/src/libcamera/pipeline/simple/simple.cpp > +++ b/src/libcamera/pipeline/simple/simple.cpp > @@ -284,6 +284,7 @@ public: > std::vector<std::unique_ptr<FrameBuffer>> conversionBuffers_; > std::queue<std::map<const Stream *, FrameBuffer *>> conversionQueue_; > bool useConversion_; > + void clearIncompleteRequests(); > > std::unique_ptr<Converter> converter_; > std::unique_ptr<SoftwareIsp> swIsp_; > @@ -897,6 +898,19 @@ void SimpleCameraData::conversionOutputDone(FrameBuffer *buffer) > pipe->completeRequest(request); > } > > +void SimpleCameraData::clearIncompleteRequests() > +{ > + while (!conversionQueue_.empty()) { > + for (auto &item : conversionQueue_.front()) { > + FrameBuffer *outputBuffer = item.second; > + Request *request = outputBuffer->request(); > + pipe()->completeBuffer(request, outputBuffer); > + pipe()->completeRequest(request); > + } > + conversionQueue_.pop(); > + } > +} > + > void SimpleCameraData::ispStatsReady(uint32_t frame, uint32_t bufferId) > { > swIsp_->processStats(frame, bufferId, > @@ -1407,6 +1421,7 @@ void SimplePipelineHandler::stopDevice(Camera *camera) > video->bufferReady.disconnect(data, &SimpleCameraData::bufferReady); > > data->conversionBuffers_.clear(); > + data->clearIncompleteRequests(); > > releasePipeline(data); > }
Quoting Robert Mader (2024-10-08 17:19:51) > Hey, thanks a lot for the patch! > > I gave it a quick try on my Pixel 3a and while the revision here avoids > the assertion most of the time and makes things much more stable, I > still managed to trigger it with enough trying (4 buffers, > starting/stopping/switching cameras in Gnome Snapshot). I haven't tried > the suggestion from Kieran yet, but to me it looks like Stop() is > currently still somehow racy - at least the way it's used by Pipewire. This current version of the patch 'completes' the buffers/requests - so I am weary pipewire probably tries to immediately resend them back into libcamera! (Though I think we should reject any incoming requests as soon as we hit stop()) But I think it's important to make sure they are 'cancelled'. -- Kieran > > Regards > > On 08.10.24 17:09, Milan Zamazal wrote: > > PipelineHandler::stop() calls stopDevice() method to perform pipeline > > specific cleanup and then completes waiting requests. If any queued > > requests remain, an assertion error is raised. > > > > Software ISP stores request buffers in > > SimpleCameraData::conversionQueue_ and queues them as V4L2 signals > > bufferReady. stopDevice() cleanup forgets to clean up the buffers and > > their requests from conversionQueue_, possibly resulting in the > > assertion error. This patch fixes the omission. > > > > The problem wasn't very visible when > > SimplePipelineHandler::kNumInternalBuffers (the number of buffers > > allocated in V4L2) was equal to the number of buffers exported from > > software ISP. But when the number of the exported buffers was increased > > by one in commit abe2ec64f9e4e97bbdfe3a50372611bd7b5315c2, the assertion > > error started pop up in some environments. Increasing the number of the > > buffers much more, e.g. to 9, makes the problem very reproducible. > > > > Each pipeline uses its own mechanism to track the requests to clean up > > and it can't be excluded that similar omissions are present in other > > places. But there is no obvious way to make a common cleanup for all > > the pipelines (except for doing it instead of raising the assertion > > error, which is probably undesirable, in order not to hide incomplete > > pipeline specific cleanups). > > > > Bug: https://bugs.libcamera.org/show_bug.cgi?id=234 > > Signed-off-by: Milan Zamazal <mzamazal@redhat.com> > > --- > > src/libcamera/pipeline/simple/simple.cpp | 15 +++++++++++++++ > > 1 file changed, 15 insertions(+) > > > > diff --git a/src/libcamera/pipeline/simple/simple.cpp b/src/libcamera/pipeline/simple/simple.cpp > > index 3ddce71d3..4e8504922 100644 > > --- a/src/libcamera/pipeline/simple/simple.cpp > > +++ b/src/libcamera/pipeline/simple/simple.cpp > > @@ -284,6 +284,7 @@ public: > > std::vector<std::unique_ptr<FrameBuffer>> conversionBuffers_; > > std::queue<std::map<const Stream *, FrameBuffer *>> conversionQueue_; > > bool useConversion_; > > + void clearIncompleteRequests(); > > > > std::unique_ptr<Converter> converter_; > > std::unique_ptr<SoftwareIsp> swIsp_; > > @@ -897,6 +898,19 @@ void SimpleCameraData::conversionOutputDone(FrameBuffer *buffer) > > pipe->completeRequest(request); > > } > > > > +void SimpleCameraData::clearIncompleteRequests() > > +{ > > + while (!conversionQueue_.empty()) { > > + for (auto &item : conversionQueue_.front()) { > > + FrameBuffer *outputBuffer = item.second; > > + Request *request = outputBuffer->request(); > > + pipe()->completeBuffer(request, outputBuffer); > > + pipe()->completeRequest(request); > > + } > > + conversionQueue_.pop(); > > + } > > +} > > + > > void SimpleCameraData::ispStatsReady(uint32_t frame, uint32_t bufferId) > > { > > swIsp_->processStats(frame, bufferId, > > @@ -1407,6 +1421,7 @@ void SimplePipelineHandler::stopDevice(Camera *camera) > > video->bufferReady.disconnect(data, &SimpleCameraData::bufferReady); > > > > data->conversionBuffers_.clear(); > > + data->clearIncompleteRequests(); > > > > releasePipeline(data); > > } > > -- > Robert Mader > Consultant Software Developer > > Collabora Ltd. > Platinum Building, St John's Innovation Park, Cambridge CB4 0DS, UK > Registered in England & Wales, no. 5513718 >
Hi Kieran, thank you for review. Kieran Bingham <kieran.bingham@ideasonboard.com> writes: > Quoting Milan Zamazal (2024-10-08 16:09:16) >> PipelineHandler::stop() calls stopDevice() method to perform pipeline >> specific cleanup and then completes waiting requests. If any queued > >> requests remain, an assertion error is raised. >> >> Software ISP stores request buffers in >> SimpleCameraData::conversionQueue_ and queues them as V4L2 signals >> bufferReady. stopDevice() cleanup forgets to clean up the buffers and >> their requests from conversionQueue_, possibly resulting in the >> assertion error. This patch fixes the omission. >> >> The problem wasn't very visible when >> SimplePipelineHandler::kNumInternalBuffers (the number of buffers >> allocated in V4L2) was equal to the number of buffers exported from >> software ISP. But when the number of the exported buffers was increased >> by one in commit abe2ec64f9e4e97bbdfe3a50372611bd7b5315c2, the assertion >> error started pop up in some environments. Increasing the number of the >> buffers much more, e.g. to 9, makes the problem very reproducible. >> >> Each pipeline uses its own mechanism to track the requests to clean up >> and it can't be excluded that similar omissions are present in other >> places. But there is no obvious way to make a common cleanup for all >> the pipelines (except for doing it instead of raising the assertion >> error, which is probably undesirable, in order not to hide incomplete >> pipeline specific cleanups). > > Indeed, I think that's why I added the assertion to make sure we force > Pipeline handlers to do 'the right thing for that handler'. Maybe we > could relax that in the future if it becomes apparetnly safe ... but I > think this patch is probably the right direction for now. > > >> >> Bug: https://bugs.libcamera.org/show_bug.cgi?id=234 >> Signed-off-by: Milan Zamazal <mzamazal@redhat.com> >> --- >> src/libcamera/pipeline/simple/simple.cpp | 15 +++++++++++++++ >> 1 file changed, 15 insertions(+) >> >> diff --git a/src/libcamera/pipeline/simple/simple.cpp b/src/libcamera/pipeline/simple/simple.cpp >> index 3ddce71d3..4e8504922 100644 >> --- a/src/libcamera/pipeline/simple/simple.cpp >> +++ b/src/libcamera/pipeline/simple/simple.cpp >> @@ -284,6 +284,7 @@ public: >> std::vector<std::unique_ptr<FrameBuffer>> conversionBuffers_; >> std::queue<std::map<const Stream *, FrameBuffer *>> conversionQueue_; >> bool useConversion_; >> + void clearIncompleteRequests(); >> >> std::unique_ptr<Converter> converter_; >> std::unique_ptr<SoftwareIsp> swIsp_; >> @@ -897,6 +898,19 @@ void SimpleCameraData::conversionOutputDone(FrameBuffer *buffer) >> pipe->completeRequest(request); >> } >> >> +void SimpleCameraData::clearIncompleteRequests() >> +{ >> + while (!conversionQueue_.empty()) { >> + for (auto &item : conversionQueue_.front()) { >> + FrameBuffer *outputBuffer = item.second; >> + Request *request = outputBuffer->request(); > > > I think somewhere here we should be marking the buffers as cancelled > before we complete it: > outputBuffer->_d()->cancel(); Ah, right. >> + pipe()->completeBuffer(request, outputBuffer); >> + pipe()->completeRequest(request); > > in fact both those lines might be better as: > > request->_d()->cancel(); > pipe()->completeRequest(request); > > as I think request->_d()->cancel(); will correctly mark all buffers as > cancelled, and the request itself. Yes, it should. request->_d()->cancel() is private; but as those two lines are already used twice in pipeline_handler.cpp, I'll extract them to a separate method and will call it from here. > With that handled, and retested: > > > Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com> > > >> + } >> + conversionQueue_.pop(); >> + } >> +} >> + >> void SimpleCameraData::ispStatsReady(uint32_t frame, uint32_t bufferId) >> { >> swIsp_->processStats(frame, bufferId, >> @@ -1407,6 +1421,7 @@ void SimplePipelineHandler::stopDevice(Camera *camera) >> video->bufferReady.disconnect(data, &SimpleCameraData::bufferReady); >> >> data->conversionBuffers_.clear(); >> + data->clearIncompleteRequests(); >> >> releasePipeline(data); >> } >> -- >> 2.44.1 >>
Quoting Milan Zamazal (2024-10-09 08:59:07) > Hi Kieran, > > thank you for review. > > Kieran Bingham <kieran.bingham@ideasonboard.com> writes: > > > Quoting Milan Zamazal (2024-10-08 16:09:16) > >> PipelineHandler::stop() calls stopDevice() method to perform pipeline > >> specific cleanup and then completes waiting requests. If any queued > > > >> requests remain, an assertion error is raised. > >> > >> Software ISP stores request buffers in > >> SimpleCameraData::conversionQueue_ and queues them as V4L2 signals > >> bufferReady. stopDevice() cleanup forgets to clean up the buffers and > >> their requests from conversionQueue_, possibly resulting in the > >> assertion error. This patch fixes the omission. > >> > >> The problem wasn't very visible when > >> SimplePipelineHandler::kNumInternalBuffers (the number of buffers > >> allocated in V4L2) was equal to the number of buffers exported from > >> software ISP. But when the number of the exported buffers was increased > >> by one in commit abe2ec64f9e4e97bbdfe3a50372611bd7b5315c2, the assertion > >> error started pop up in some environments. Increasing the number of the > >> buffers much more, e.g. to 9, makes the problem very reproducible. > >> > >> Each pipeline uses its own mechanism to track the requests to clean up > >> and it can't be excluded that similar omissions are present in other > >> places. But there is no obvious way to make a common cleanup for all > >> the pipelines (except for doing it instead of raising the assertion > >> error, which is probably undesirable, in order not to hide incomplete > >> pipeline specific cleanups). > > > > Indeed, I think that's why I added the assertion to make sure we force > > Pipeline handlers to do 'the right thing for that handler'. Maybe we > > could relax that in the future if it becomes apparetnly safe ... but I > > think this patch is probably the right direction for now. > > > > > >> > >> Bug: https://bugs.libcamera.org/show_bug.cgi?id=234 > >> Signed-off-by: Milan Zamazal <mzamazal@redhat.com> > >> --- > >> src/libcamera/pipeline/simple/simple.cpp | 15 +++++++++++++++ > >> 1 file changed, 15 insertions(+) > >> > >> diff --git a/src/libcamera/pipeline/simple/simple.cpp b/src/libcamera/pipeline/simple/simple.cpp > >> index 3ddce71d3..4e8504922 100644 > >> --- a/src/libcamera/pipeline/simple/simple.cpp > >> +++ b/src/libcamera/pipeline/simple/simple.cpp > >> @@ -284,6 +284,7 @@ public: > >> std::vector<std::unique_ptr<FrameBuffer>> conversionBuffers_; > >> std::queue<std::map<const Stream *, FrameBuffer *>> conversionQueue_; > >> bool useConversion_; > >> + void clearIncompleteRequests(); > >> > >> std::unique_ptr<Converter> converter_; > >> std::unique_ptr<SoftwareIsp> swIsp_; > >> @@ -897,6 +898,19 @@ void SimpleCameraData::conversionOutputDone(FrameBuffer *buffer) > >> pipe->completeRequest(request); > >> } > >> > >> +void SimpleCameraData::clearIncompleteRequests() > >> +{ > >> + while (!conversionQueue_.empty()) { > >> + for (auto &item : conversionQueue_.front()) { > >> + FrameBuffer *outputBuffer = item.second; > >> + Request *request = outputBuffer->request(); > > > > > > I think somewhere here we should be marking the buffers as cancelled > > before we complete it: > > outputBuffer->_d()->cancel(); > > Ah, right. > > >> + pipe()->completeBuffer(request, outputBuffer); > >> + pipe()->completeRequest(request); > > > > in fact both those lines might be better as: > > > > request->_d()->cancel(); > > pipe()->completeRequest(request); > > > > as I think request->_d()->cancel(); will correctly mark all buffers as > > cancelled, and the request itself. > > Yes, it should. request->_d()->cancel() is private; but as those two > lines are already used twice in pipeline_handler.cpp, I'll extract them > to a separate method and will call it from here. Great, - indeed the first thing I went looking for was "pipe()->cancelReqeust(request)" which isn't there (yet :D) -- Kieran > > > With that handled, and retested: > > > > > > Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com> > > > > > >> + } > >> + conversionQueue_.pop(); > >> + } > >> +} > >> + > >> void SimpleCameraData::ispStatsReady(uint32_t frame, uint32_t bufferId) > >> { > >> swIsp_->processStats(frame, bufferId, > >> @@ -1407,6 +1421,7 @@ void SimplePipelineHandler::stopDevice(Camera *camera) > >> video->bufferReady.disconnect(data, &SimpleCameraData::bufferReady); > >> > >> data->conversionBuffers_.clear(); > >> + data->clearIncompleteRequests(); > >> > >> releasePipeline(data); > >> } > >> -- > >> 2.44.1 > >> >
diff --git a/src/libcamera/pipeline/simple/simple.cpp b/src/libcamera/pipeline/simple/simple.cpp index 3ddce71d3..4e8504922 100644 --- a/src/libcamera/pipeline/simple/simple.cpp +++ b/src/libcamera/pipeline/simple/simple.cpp @@ -284,6 +284,7 @@ public: std::vector<std::unique_ptr<FrameBuffer>> conversionBuffers_; std::queue<std::map<const Stream *, FrameBuffer *>> conversionQueue_; bool useConversion_; + void clearIncompleteRequests(); std::unique_ptr<Converter> converter_; std::unique_ptr<SoftwareIsp> swIsp_; @@ -897,6 +898,19 @@ void SimpleCameraData::conversionOutputDone(FrameBuffer *buffer) pipe->completeRequest(request); } +void SimpleCameraData::clearIncompleteRequests() +{ + while (!conversionQueue_.empty()) { + for (auto &item : conversionQueue_.front()) { + FrameBuffer *outputBuffer = item.second; + Request *request = outputBuffer->request(); + pipe()->completeBuffer(request, outputBuffer); + pipe()->completeRequest(request); + } + conversionQueue_.pop(); + } +} + void SimpleCameraData::ispStatsReady(uint32_t frame, uint32_t bufferId) { swIsp_->processStats(frame, bufferId, @@ -1407,6 +1421,7 @@ void SimplePipelineHandler::stopDevice(Camera *camera) video->bufferReady.disconnect(data, &SimpleCameraData::bufferReady); data->conversionBuffers_.clear(); + data->clearIncompleteRequests(); releasePipeline(data); }
PipelineHandler::stop() calls stopDevice() method to perform pipeline specific cleanup and then completes waiting requests. If any queued requests remain, an assertion error is raised. Software ISP stores request buffers in SimpleCameraData::conversionQueue_ and queues them as V4L2 signals bufferReady. stopDevice() cleanup forgets to clean up the buffers and their requests from conversionQueue_, possibly resulting in the assertion error. This patch fixes the omission. The problem wasn't very visible when SimplePipelineHandler::kNumInternalBuffers (the number of buffers allocated in V4L2) was equal to the number of buffers exported from software ISP. But when the number of the exported buffers was increased by one in commit abe2ec64f9e4e97bbdfe3a50372611bd7b5315c2, the assertion error started pop up in some environments. Increasing the number of the buffers much more, e.g. to 9, makes the problem very reproducible. Each pipeline uses its own mechanism to track the requests to clean up and it can't be excluded that similar omissions are present in other places. But there is no obvious way to make a common cleanup for all the pipelines (except for doing it instead of raising the assertion error, which is probably undesirable, in order not to hide incomplete pipeline specific cleanups). Bug: https://bugs.libcamera.org/show_bug.cgi?id=234 Signed-off-by: Milan Zamazal <mzamazal@redhat.com> --- src/libcamera/pipeline/simple/simple.cpp | 15 +++++++++++++++ 1 file changed, 15 insertions(+)