From 8806863b0bc4498d098e16dda657ab6f8293d208 Mon Sep 17 00:00:00 2001 From: Jacopo Mondi Date: Tue, 6 Oct 2020 17:53:51 +0200 Subject: android: camera_worker: Introduce CameraWorker MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The Android camera framework provides for each buffer part of a capture request an acquisition fence the camera HAL is supposed to wait on before using the buffer. As the libcamera HAL runs in the camera service thread, it is not possible to perform a synchronous wait there. Introduce a CameraWorker class that runs an internal thread to wait on a set of fences before queueing a capture request to the libcamera::Camera. Fences completion is handled through a simple poll, similar in implementation to the sync_wait() function provided by libdrm. Reviewed-by: Niklas Söderlund Reviewed-by: Laurent Pinchart Signed-off-by: Jacopo Mondi --- src/android/camera_worker.cpp | 122 ++++++++++++++++++++++++++++++++++++++++++ src/android/camera_worker.h | 63 ++++++++++++++++++++++ src/android/meson.build | 1 + 3 files changed, 186 insertions(+) create mode 100644 src/android/camera_worker.cpp create mode 100644 src/android/camera_worker.h diff --git a/src/android/camera_worker.cpp b/src/android/camera_worker.cpp new file mode 100644 index 00000000..ff09b75e --- /dev/null +++ b/src/android/camera_worker.cpp @@ -0,0 +1,122 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ +/* + * Copyright (C) 2020, Google Inc. + * + * camera_worker.cpp - Process capture requests on behalf of the Camera HAL + */ + +#include "camera_worker.h" + +#include +#include +#include + +#include "camera_device.h" + +using namespace libcamera; + +LOG_DECLARE_CATEGORY(HAL); + +/* + * \class CaptureRequest + * \brief Wrap a libcamera::Request associated with buffers and fences + * + * A CaptureRequest is constructed by the CameraDevice, filled with + * buffers and fences provided by the camera3 framework and then processed + * by the CameraWorker which queues it to the libcamera::Camera after handling + * fences. + */ +CaptureRequest::CaptureRequest(libcamera::Camera *camera, uint64_t cookie) + : camera_(camera) +{ + request_ = camera_->createRequest(cookie); +} + +void CaptureRequest::addBuffer(Stream *stream, FrameBuffer *buffer, int fence) +{ + request_->addBuffer(stream, buffer); + acquireFences_.push_back(fence); +} + +void CaptureRequest::queue() +{ + camera_->queueRequest(request_.get()); +} + +/* + * \class CameraWorker + * \brief Process a CaptureRequest on an internal thread + * + * The CameraWorker class wraps a Worker that runs on an internal thread + * and schedules processing of CaptureRequest through it. + */ +CameraWorker::CameraWorker() +{ + worker_.moveToThread(&thread_); +} + +void CameraWorker::start() +{ + thread_.start(); +} + +void CameraWorker::stop() +{ + thread_.exit(); + thread_.wait(); +} + +void CameraWorker::queueRequest(CaptureRequest *request) +{ + /* Async process the request on the worker which runs its own thread. */ + worker_.invokeMethod(&Worker::processRequest, ConnectionTypeQueued, + request); +} + +/* + * \class CameraWorker::Worker + * \brief Process a CaptureRequest handling acquisition fences + */ +int CameraWorker::Worker::waitFence(int fence) +{ + /* + * \todo Better characterize the timeout. Currently equal to the one + * used by the Rockchip Camera HAL on ChromeOS. + */ + constexpr unsigned int timeoutMs = 300; + struct pollfd fds = { fence, POLLIN, 0 }; + + do { + int ret = poll(&fds, 1, timeoutMs); + if (ret == 0) + return -ETIME; + + if (ret > 0) { + if (fds.revents & (POLLERR | POLLNVAL)) + return -EINVAL; + + return 0; + } + } while (errno == EINTR || errno == EAGAIN); + + return -errno; +} + +void CameraWorker::Worker::processRequest(CaptureRequest *request) +{ + /* Wait on all fences before queuing the Request. */ + for (int fence : request->fences()) { + if (fence == -1) + continue; + + int ret = waitFence(fence); + close(fence); + if (ret < 0) { + LOG(HAL, Error) << "Failed waiting for fence: " + << fence << ": " << strerror(-ret); + return; + } + } + + request->queue(); +} diff --git a/src/android/camera_worker.h b/src/android/camera_worker.h new file mode 100644 index 00000000..fff50217 --- /dev/null +++ b/src/android/camera_worker.h @@ -0,0 +1,63 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ +/* + * Copyright (C) 2020, Google Inc. + * + * camera_worker.h - Process capture requests on behalf of the Camera HAL + */ +#ifndef __ANDROID_CAMERA_WORKER_H__ +#define __ANDROID_CAMERA_WORKER_H__ + +#include + +#include +#include +#include +#include +#include + +#include "libcamera/internal/thread.h" + +class CameraDevice; + +class CaptureRequest +{ +public: + CaptureRequest(libcamera::Camera *camera, uint64_t cookie); + + const std::vector &fences() const { return acquireFences_; } + + void addBuffer(libcamera::Stream *stream, + libcamera::FrameBuffer *buffer, int fence); + void queue(); + +private: + libcamera::Camera *camera_; + std::vector acquireFences_; + std::unique_ptr request_; +}; + +class CameraWorker +{ +public: + CameraWorker(); + + void start(); + void stop(); + + void queueRequest(CaptureRequest *request); + +private: + class Worker : public libcamera::Object + { + public: + void processRequest(CaptureRequest *request); + + private: + int waitFence(int fence); + }; + + Worker worker_; + libcamera::Thread thread_; +}; + +#endif /* __ANDROID_CAMERA_WORKER_H__ */ diff --git a/src/android/meson.build b/src/android/meson.build index 802bb89a..b2b2293c 100644 --- a/src/android/meson.build +++ b/src/android/meson.build @@ -21,6 +21,7 @@ android_hal_sources = files([ 'camera_metadata.cpp', 'camera_ops.cpp', 'camera_stream.cpp', + 'camera_worker.cpp', 'jpeg/encoder_libjpeg.cpp', 'jpeg/exif.cpp', ]) -- cgit v1.2.1