[libcamera-devel] [PATCH] Revert "pipeline: raspberrypi: Do not unconditionally free buffers on close"

[Naushir Patuck]

Hi David,

Thank you for the patch!

On Wed, 9 Nov 2022 at 10:16, David Plowman via libcamera-devel <
libcamera-devel at lists.libcamera.org> wrote:

> This reverts commit 30d704732badc675f72fe73d14749669cb645c23.
>
> It turns out that this commit causes some regressions and is in fact
> unnecessary because the related commit "libcamera: v4l2_videodevice:
> Guard against releasing unallocated buffers"
> (a2bdff6d0b67475492ac7cf9318866b6d89a28fd) fixes the problem
> completely (if the buffers were never allocated, the video device
> avoids trying to free them even if the pipeline handler asks).
>
> The reason for the regressions is that in this new (broken) scheme we
> would never call clearBuffers() on all the streams if the internal
> buffers were never allocated (i.e. buffersAllocated_ is never
> set). This causes the stream's bufferMap_ list to get longer and
> longer if there are multiple back-to-back calls to configure, and
> dev_->importBuffers() will ultimately to fail.
>
> So either we need to think more carefully about how to stop the
> pipeline handler from freeing buffers that it doesn't own, or we just
> leave it as the other commit resolves the problem on its own. In the
> interim, simply reverting this commit certainly seems like the best
> solution.
>
> Signed-off-by: David Plowman <david.plowman at raspberrypi.com>
>

Probably worth adding a Fixes tag here.

Reviewed-by: Naushir Patuck <naush at raspberrypi.com>


> ---
>  src/libcamera/pipeline/raspberrypi/raspberrypi.cpp | 3 ---
>  1 file changed, 3 deletions(-)
>
> diff --git a/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
> b/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
> index 1b599fcc..343f8cb2 100644
> --- a/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
> +++ b/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
> @@ -1506,9 +1506,6 @@ void PipelineHandlerRPi::mapBuffers(Camera *camera,
> const RPi::BufferMap &buffer
>
>  void RPiCameraData::freeBuffers()
>  {
> -       if (!buffersAllocated_)
> -               return;
> -
>         if (ipa_) {
>                 /*
>                  * Copy the buffer ids from the unordered_set to a vector
> to
> --
> 2.30.2
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.libcamera.org/pipermail/libcamera-devel/attachments/20221109/d784cc27/attachment.htm>