[libcamera-devel] [PATCH v3 0/5] Raspberry Pi: Efficient start/stop/start sequences

[Laurent Pinchart]

On Mon, Mar 21, 2022 at 10:26:57AM +0000, Naushir Patuck via libcamera-devel wrote:
> Hi,
> 
> For version 3 of this series, I've removed the patch to add a timer that waits
> for 5s after stop() to de-allocate buffers.  David and me have had a chat about
> this and we think for now it is best that we have fully deterministic behavior for
> buffer allocations, and avoid CMA fragmentation on the Raspberry Pi platforms.

For what it's worth, I agree about the deterministic behaviour. We can
work on top of this series to add a hint to the stop() function to tell
the pipeline handler if streaming is expected to be restarted soon.

> Apart from that, I have renamed the reallocate flag based on Kieran's suggestion.
> 
> Regards,
> Naush
> 
> Naushir Patuck (5):
>   pipeline: raspberrypi: Avoid over-allocation for ISP Output 1
>   pipeline: raspberrypi: Move freeBuffers() to the RPiCameraData class
>   pipeline: raspberrypi: Free buffers in the RPiCamera destructor and
>     re-configure
>   pipeline: raspberrypi: Repurpose RPi::Stream::reset()
>   libcamera: v4l2_videodevice: Empty the V4L2 buffer cache on
>     streamOff()
> 
>  include/libcamera/internal/v4l2_videodevice.h |  1 +
>  .../pipeline/raspberrypi/raspberrypi.cpp      | 58 ++++++++++++-------
>  .../pipeline/raspberrypi/rpi_stream.cpp       | 13 ++---
>  .../pipeline/raspberrypi/rpi_stream.h         |  2 +-
>  src/libcamera/v4l2_videodevice.cpp            | 16 +++++
>  5 files changed, 61 insertions(+), 29 deletions(-)

-- 
Regards,

Laurent Pinchart