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Jarkko Sakkinen
jarkko
One last thing inherited from v4l2-loopback is kcalloc(), which I dislike given that it is unaccounted memory for a process.
The solution is to make "server side" using vcam ioctl API exclusive dma-buf based because they provide all the robustness. Depending on allocator they can be memcg accounted and they can be also sent between processes.
I.e. I had some harmful robustness that is really unnecessary given that user space camera driver is specialized software to begin with.
It does not affect /dev/videoX, which runs on different VB2 queue supporting userptr, mmap and dma-buf.
The solution is to make "server side" using vcam ioctl API exclusive dma-buf based because they provide all the robustness. Depending on allocator they can be memcg accounted and they can be also sent between processes.
I.e. I had some harmful robustness that is really unnecessary given that user space camera driver is specialized software to begin with.
It does not affect /dev/videoX, which runs on different VB2 queue supporting userptr, mmap and dma-buf.
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