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    "msgid": "<20260626113325.3218045-1-bryan.odonoghue@linaro.org>",
    "date": "2026-06-26T11:33:17",
    "name": "[v3,0/8] libcamera: software_isp: gpu: Add go faster stripes",
    "submitter": {
        "id": 175,
        "url": "https://patchwork.libcamera.org/api/people/175/?format=api",
        "name": "Bryan O'Donoghue",
        "email": "bryan.odonoghue@linaro.org"
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            "date": "2026-06-26T11:33:17",
            "name": "libcamera: software_isp: gpu: Add go faster stripes",
            "version": 3,
            "mbox": "https://patchwork.libcamera.org/series/6020/mbox/"
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        "From": "Bryan O'Donoghue <bryan.odonoghue@linaro.org>",
        "To": "libcamera-devel@lists.libcamera.org",
        "Cc": "bryan.odonoghue@linaro.org,\n\tpavel@ucw.cz",
        "Subject": "[PATCH v3 0/8] libcamera: software_isp: gpu: Add go faster stripes",
        "Date": "Fri, 26 Jun 2026 12:33:17 +0100",
        "Message-ID": "<20260626113325.3218045-1-bryan.odonoghue@linaro.org>",
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    },
    "content": "v3:\n- Fixes a missing switch default from libcamera ci loop - bod\n\nv2:\n- Reverts to debayer_egl specific caching mechanism - Laurent\n- Pivots on dmabuf handle as key for cache. dmabuf handle\n  must be unique between start() and stop() for eglCreateImageKHR to work - Barnabas\n- Ensures sizeof cache doesn't exceed the number of expected buffers\n  as discovered during configure() - Barnabas\n- Drops GL_16F patch - Robert\n- Drops the \"input\" name from createInputTexture2D() - Robert\n- Adds RB as specified by Robert\n\nv1:\nFollowing on from Robert Mader's ask to bring forward GPUISP multi-pass\ncache operations to mainline first, I've done some work to enable that.\n\nThis series implements an input/output texture caching scheme which results\nin an overall absolute 4.5 millisecond - roughly improvement in performance\nper processed frame. This is a bit of an odd result as I was expecting to\nshave a particular % off of each frame in the order of 20% or so. My best\nguess is that particular paths we are optimising here are around texture\ngeneration and these are \"fixed costs\" on the CPU side.\n\nOne very welcome outcome of this series is genuine zero-copy on dma-buf\npaths we can support it on i.e. on paths where the CSI2 and GPU strides\nagree.\n\nThe numbers cited in my example are for non dma-buf handle upload and\ndma-buf handle render-to-texture on the output so, in fact I'd expect to\nsee a much larger improvement on systems where dma-buf handle is used on\nboth paths.\n\nAs it is on my test reference systems I have a 50% improvement per frame\nfor one system, a 20% improvement on another system or we could view it as\na fixed 4.5 millisecond improvement on both.\n\nI implemented the cache around V4L2BufferCache as per Barnabas' suggestion,\nincluding a fixed cache size.\n\nBryan O'Donoghue (8):\n  libcamera: software_isp: debayer_egl: Pass eglImage as parameter to\n    setShaderVariables\n  libcamera: software_isp: debayer_egl: Flag dmabuf use once per session\n    not for every frame\n  libcamera: egl: Add new helper attachTextureToFBO\n  libcamera: egl: Add createOutputTexture2D\n  libcamera: egl: Add updateTexture2D\n  libcamera: egl: Add activateBindTexture\n  libcamera: egl: Drop dmabuf_import_failed_\n  libcamera: software_isp: debayer_egl: Implement input/output frame\n    caching mechanism\n\n include/libcamera/internal/egl.h           |   6 +-\n src/libcamera/egl.cpp                      | 115 +++++++++++++++++----\n src/libcamera/software_isp/debayer_egl.cpp |  98 +++++++++++++-----\n src/libcamera/software_isp/debayer_egl.h   |  14 ++-\n 4 files changed, 185 insertions(+), 48 deletions(-)"
}