gpu/command_buffer/common/id_allocator_test.cc

   1 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 // This file has the unit tests for the IdAllocator class.
   6
   7 #include "gpu/command_buffer/common/id_allocator.h"
   8 #include "testing/gtest/include/gtest/gtest.h"
   9
  10 namespace gpu {
  11
  12 class IdAllocatorTest : public testing::Test {
  13  protected:
  14   virtual void SetUp() {}
  15   virtual void TearDown() {}
  16
  17   IdAllocator* id_allocator() { return &id_allocator_; }
  18
  19  private:
  20   IdAllocator id_allocator_;
  21 };
  22
  23 // Checks basic functionality: AllocateID, FreeID, InUse.
  24 TEST_F(IdAllocatorTest, TestBasic) {
  25   IdAllocator *allocator = id_allocator();
  26   // Check that resource 1 is not in use
  27   EXPECT_FALSE(allocator->InUse(1));
  28
  29   // Allocate an ID, check that it's in use.
  30   ResourceId id1 = allocator->AllocateID();
  31   EXPECT_TRUE(allocator->InUse(id1));
  32
  33   // Allocate another ID, check that it's in use, and different from the first
  34   // one.
  35   ResourceId id2 = allocator->AllocateID();
  36   EXPECT_TRUE(allocator->InUse(id2));
  37   EXPECT_NE(id1, id2);
  38
  39   // Free one of the IDs, check that it's not in use any more.
  40   allocator->FreeID(id1);
  41   EXPECT_FALSE(allocator->InUse(id1));
  42
  43   // Frees the other ID, check that it's not in use any more.
  44   allocator->FreeID(id2);
  45   EXPECT_FALSE(allocator->InUse(id2));
  46 }
  47
  48 // Checks that the resource IDs are re-used after being freed.
  49 TEST_F(IdAllocatorTest, TestAdvanced) {
  50   IdAllocator *allocator = id_allocator();
  51
  52   // Allocate the highest possible ID, to make life awkward.
  53   allocator->AllocateIDAtOrAbove(-1);
  54
  55   // Allocate a significant number of resources.
  56   const unsigned int kNumResources = 100;
  57   ResourceId ids[kNumResources];
  58   for (unsigned int i = 0; i < kNumResources; ++i) {
  59     ids[i] = allocator->AllocateID();
  60     EXPECT_TRUE(allocator->InUse(ids[i]));
  61   }
  62
  63   // Check that a new allocation re-uses the resource we just freed.
  64   ResourceId id1 = ids[kNumResources / 2];
  65   allocator->FreeID(id1);
  66   EXPECT_FALSE(allocator->InUse(id1));
  67   ResourceId id2 = allocator->AllocateID();
  68   EXPECT_TRUE(allocator->InUse(id2));
  69   EXPECT_EQ(id1, id2);
  70 }
  71
  72 // Checks that we can choose our own ids and they won't be reused.
  73 TEST_F(IdAllocatorTest, MarkAsUsed) {
  74   IdAllocator* allocator = id_allocator();
  75   ResourceId id = allocator->AllocateID();
  76   allocator->FreeID(id);
  77   EXPECT_FALSE(allocator->InUse(id));
  78   EXPECT_TRUE(allocator->MarkAsUsed(id));
  79   EXPECT_TRUE(allocator->InUse(id));
  80   ResourceId id2 = allocator->AllocateID();
  81   EXPECT_NE(id, id2);
  82   EXPECT_TRUE(allocator->MarkAsUsed(id2 + 1));
  83   ResourceId id3 = allocator->AllocateID();
  84   // Checks our algorithm. If the algorithm changes this check should be
  85   // changed.
  86   EXPECT_EQ(id3, id2 + 2);
  87 }
  88
  89 // Checks AllocateIdAtOrAbove.
  90 TEST_F(IdAllocatorTest, AllocateIdAtOrAbove) {
  91   const ResourceId kOffset = 123456;
  92   IdAllocator* allocator = id_allocator();
  93   ResourceId id1 = allocator->AllocateIDAtOrAbove(kOffset);
  94   EXPECT_EQ(kOffset, id1);
  95   ResourceId id2 = allocator->AllocateIDAtOrAbove(kOffset);
  96   EXPECT_GT(id2, kOffset);
  97   ResourceId id3 = allocator->AllocateIDAtOrAbove(kOffset);
  98   EXPECT_GT(id3, kOffset);
  99 }
 100
 101 // Checks that AllocateIdAtOrAbove wraps around at the maximum 32-bit value.
 102 TEST_F(IdAllocatorTest, AllocateIdAtOrAboveWrapsAround) {
 103   const ResourceId kMaxPossibleOffset = -1;
 104   IdAllocator* allocator = id_allocator();
 105   ResourceId id1 = allocator->AllocateIDAtOrAbove(kMaxPossibleOffset);
 106   EXPECT_EQ(kMaxPossibleOffset, id1);
 107   ResourceId id2 = allocator->AllocateIDAtOrAbove(kMaxPossibleOffset);
 108   EXPECT_EQ(1u, id2);
 109   ResourceId id3 = allocator->AllocateIDAtOrAbove(kMaxPossibleOffset);
 110   EXPECT_EQ(2u, id3);
 111 }
 112
 113 TEST_F(IdAllocatorTest, RedundantFreeIsIgnored) {
 114   IdAllocator* allocator = id_allocator();
 115   ResourceId id1 = allocator->AllocateID();
 116   allocator->FreeID(0);
 117   allocator->FreeID(id1);
 118   allocator->FreeID(id1);
 119   allocator->FreeID(id1 + 1);
 120
 121   ResourceId id2 = allocator->AllocateID();
 122   ResourceId id3 = allocator->AllocateID();
 123   EXPECT_NE(id2, id3);
 124   EXPECT_NE(kInvalidResource, id2);
 125   EXPECT_NE(kInvalidResource, id3);
 126 }
 127
 128 }  // namespace gpu