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   bool success = false;
  64   auto ret = MakeUnique<SwapChainPresenter>(*this);
  65   const auto old = ret->SwapBackBuffer(surf, success);
  66   MOZ_ALWAYS_TRUE(!old);
  67   if (NS_WARN_IF(!success)) {
  68     return nullptr;
  69   }
  70   return ret;
  71 }
  72
  73 void SwapChain::ClearPool() {
  74   mPool = {};
  75   mPrevFrontBuffer = nullptr;
  76 }
  77
  78 bool SwapChain::StoreRecycledSurface(
  79     const std::shared_ptr<SharedSurface>& surf) {
  80   MOZ_ASSERT(mFactory);
  81   if (!mFactory || NS_WARN_IF(surf->mDesc.gl != mFactory->mDesc.gl)) {
  82     // Ensure we don't accidentally store an expired shared surface or from a
  83     // different context.
  84     return false;
  85   }
  86   mPool.push(surf);
  87   return true;
  88 }
  89
  90 // -
  91
  92 SwapChainPresenter::SwapChainPresenter(SwapChain& swapChain)
  93     : mSwapChain(&swapChain) {
  94   MOZ_RELEASE_ASSERT(mSwapChain->mPresenter == nullptr);
  95   mSwapChain->mPresenter = this;
  96 }
  97
  98 SwapChainPresenter::~SwapChainPresenter() {
  99   if (!mSwapChain) return;
 100   MOZ_RELEASE_ASSERT(mSwapChain->mPresenter == this);
 101   mSwapChain->mPresenter = nullptr;
 102
 103   bool success;
 104   auto newFront = SwapBackBuffer(nullptr, success);
 105   if (newFront) {
 106     mSwapChain->mPrevFrontBuffer = mSwapChain->mFrontBuffer;
 107     mSwapChain->mFrontBuffer = newFront;
 108   }
 109 }
 110
 111 std::shared_ptr<SharedSurface> SwapChainPresenter::SwapBackBuffer(
 112     std::shared_ptr<SharedSurface> back, bool& aSuccess) {
 113   if (mBackBuffer) {
 114     mBackBuffer->UnlockProd();
 115     mBackBuffer->ProducerRelease();
 116     mBackBuffer->Commit();
 117   }
 118   auto old = mBackBuffer;
 119   mBackBuffer = back;
 120   if (mBackBuffer) {
 121     mBackBuffer->WaitForBufferOwnership();
 122     if (NS_WARN_IF(!mBackBuffer->ProducerAcquire())) {
 123       mBackBuffer = nullptr;
 124       aSuccess = false;
 125       return old;
 126     }
 127     mBackBuffer->LockProd();
 128   }
 129   aSuccess = true;
 130   return old;
 131 }
 132
 133 GLuint SwapChainPresenter::Fb() const {
 134   if (!mBackBuffer) return 0;
 135   const auto& fb = mBackBuffer->mFb;
 136   if (!fb) return 0;
 137   return fb->mFB;
 138 }
 139
 140 // -
 141 // SwapChain
 142
 143 SwapChain::SwapChain() = default;
 144
 145 SwapChain::~SwapChain() {
 146   if (mPresenter) {
 147     // Out of order destruction, but ok.
 148     bool success;
 149     (void)mPresenter->SwapBackBuffer(nullptr, success);
 150     mPresenter->mSwapChain = nullptr;
 151     mPresenter = nullptr;
 152   }
 153   if (mDestroyedCallback) {
 154     mDestroyedCallback();
 155   }
 156 }
 157
 158 }  // namespace mozilla::gl