gfx/gl/GLScreenBuffer.cpp

   1 /* -*- Mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; tab-width: 4; -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #include "GLScreenBuffer.h"
   7
   8 #include "CompositorTypes.h"
   9 #include "GLContext.h"
  10 #include "gfx2DGlue.h"
  11 #include "MozFramebuffer.h"
  12 #include "SharedSurface.h"
  13
  14 namespace mozilla::gl {
  15
  16 // -
  17 // SwapChainPresenter
  18
  19 // We need to apply pooling on Android because of the AndroidSurface slow
  20 // destructor bugs. They cause a noticeable performance hit. See bug
  21 // #1646073.
  22 static constexpr size_t kPoolSize =
  23 #if defined(MOZ_WIDGET_ANDROID)
  24     4;
  25 #else
  26     0;
  27 #endif
  28
  29 UniquePtr<SwapChainPresenter> SwapChain::Acquire(
  30     const gfx::IntSize& size, const gfx::ColorSpace2 colorSpace) {
  31   MOZ_ASSERT(mFactory);
  32
  33   std::shared_ptr<SharedSurface> surf;
  34   if (!mPool.empty()) {
  35     // Try reuse
  36     const auto& existingDesc = mPool.front()->mDesc;
  37     auto newDesc = existingDesc;
  38     newDesc.size = size;
  39     newDesc.colorSpace = colorSpace;
  40     if (newDesc != existingDesc || !mPool.front()->IsValid()) {
  41       mPool = {};
  42     }
  43   }
  44
  45   // When mDestroyedCallback exists, recycling of SharedSurfaces is managed by
  46   // the owner of the SwapChain by calling StoreRecycledSurface().
  47   const auto poolSize = mDestroyedCallback ? 0 : kPoolSize;
  48
  49   if (!mPool.empty() && (!poolSize || mPool.size() == poolSize)) {
  50     surf = mPool.front();
  51     mPool.pop();
  52   }
  53   if (!surf) {
  54     auto uniquePtrSurf = mFactory->CreateShared(size, colorSpace);
  55     if (!uniquePtrSurf) return nullptr;
  56     surf.reset(uniquePtrSurf.release());
  57   }
  58   mPool.push(surf);
  59   while (mPool.size() > poolSize) {
  60     mPool.pop();
  61   }
  62
  63   auto ret = MakeUnique<SwapChainPresenter>(*this);
  64   const auto old = ret->SwapBackBuffer(surf);
  65   MOZ_ALWAYS_TRUE(!old);
  66   return ret;
  67 }
  68
  69 void SwapChain::ClearPool() {
  70   mPool = {};
  71   mPrevFrontBuffer = nullptr;
  72 }
  73
  74 bool SwapChain::StoreRecycledSurface(
  75     const std::shared_ptr<SharedSurface>& surf) {
  76   MOZ_ASSERT(mFactory);
  77   if (!mFactory || NS_WARN_IF(surf->mDesc.gl != mFactory->mDesc.gl)) {
  78     // Ensure we don't accidentally store an expired shared surface or from a
  79     // different context.
  80     return false;
  81   }
  82   mPool.push(surf);
  83   return true;
  84 }
  85
  86 // -
  87
  88 SwapChainPresenter::SwapChainPresenter(SwapChain& swapChain)
  89     : mSwapChain(&swapChain) {
  90   MOZ_RELEASE_ASSERT(mSwapChain->mPresenter == nullptr);
  91   mSwapChain->mPresenter = this;
  92 }
  93
  94 SwapChainPresenter::~SwapChainPresenter() {
  95   if (!mSwapChain) return;
  96   MOZ_RELEASE_ASSERT(mSwapChain->mPresenter == this);
  97   mSwapChain->mPresenter = nullptr;
  98
  99   auto newFront = SwapBackBuffer(nullptr);
 100   if (newFront) {
 101     mSwapChain->mPrevFrontBuffer = mSwapChain->mFrontBuffer;
 102     mSwapChain->mFrontBuffer = newFront;
 103   }
 104 }
 105
 106 std::shared_ptr<SharedSurface> SwapChainPresenter::SwapBackBuffer(
 107     std::shared_ptr<SharedSurface> back) {
 108   if (mBackBuffer) {
 109     mBackBuffer->UnlockProd();
 110     mBackBuffer->ProducerRelease();
 111     mBackBuffer->Commit();
 112   }
 113   auto old = mBackBuffer;
 114   mBackBuffer = back;
 115   if (mBackBuffer) {
 116     mBackBuffer->WaitForBufferOwnership();
 117     mBackBuffer->ProducerAcquire();
 118     mBackBuffer->LockProd();
 119   }
 120   return old;
 121 }
 122
 123 GLuint SwapChainPresenter::Fb() const {
 124   if (!mBackBuffer) return 0;
 125   const auto& fb = mBackBuffer->mFb;
 126   if (!fb) return 0;
 127   return fb->mFB;
 128 }
 129
 130 // -
 131 // SwapChain
 132
 133 SwapChain::SwapChain() = default;
 134
 135 SwapChain::~SwapChain() {
 136   if (mPresenter) {
 137     // Out of order destruction, but ok.
 138     (void)mPresenter->SwapBackBuffer(nullptr);
 139     mPresenter->mSwapChain = nullptr;
 140     mPresenter = nullptr;
 141   }
 142   if (mDestroyedCallback) {
 143     mDestroyedCallback();
 144   }
 145 }
 146
 147 }  // namespace mozilla::gl