VmaBlockMetadata_Buddy: Introduced m_LevelCount to limit number of levels in use by particular memory block, considering new constant MIN_NODE_SIZE.
diff --git a/src/Tests.cpp b/src/Tests.cpp
index 1ccae95..9286c5c 100644
--- a/src/Tests.cpp
+++ b/src/Tests.cpp
@@ -4160,6 +4160,13 @@
&newBufInfo.Buffer, &newBufInfo.Allocation, &allocInfo);
assert(res == VK_SUCCESS);
bufInfo.push_back(newBufInfo);
+
+ // Test very small allocation, smaller than minimum node size.
+ bufCreateInfo.size = 1;
+ res = vmaCreateBuffer(g_hAllocator, &bufCreateInfo, &allocCreateInfo,
+ &newBufInfo.Buffer, &newBufInfo.Allocation, &allocInfo);
+ assert(res == VK_SUCCESS);
+ bufInfo.push_back(newBufInfo);
VmaPoolStats stats = {};
vmaGetPoolStats(g_hAllocator, pool, &stats);
diff --git a/src/vk_mem_alloc.h b/src/vk_mem_alloc.h
index 411b300..41a5a92 100644
--- a/src/vk_mem_alloc.h
+++ b/src/vk_mem_alloc.h
@@ -4971,9 +4971,11 @@
- m_UsableSize is this size aligned down to a power of two.
All allocations and calculations happen relative to m_UsableSize.
- GetUnusableSize() is the difference between them.
- It is repoted as separate unused range.
+ It is repoted as separate, unused range, not available for allocations.
-Level 0 has block size = GetSize(). Level 1 has block size = GetSize() / 2 and so on...
+Node at level 0 has size = m_UsableSize.
+Each next level contains nodes with size 2 times smaller than current level.
+m_LevelCount is the maximum number of levels to use in the current object.
*/
class VmaBlockMetadata_Buddy : public VmaBlockMetadata
{
@@ -5028,7 +5030,8 @@
virtual void FreeAtOffset(VkDeviceSize offset) { FreeAtOffset(VMA_NULL, offset); }
private:
- static const size_t MAX_LEVELS = 30; // TODO
+ static const VkDeviceSize MIN_NODE_SIZE = 32;
+ static const size_t MAX_LEVELS = 30;
struct ValidationContext
{
@@ -5075,6 +5078,8 @@
// Size of the memory block aligned down to a power of two.
VkDeviceSize m_UsableSize;
+ uint32_t m_LevelCount;
+
Node* m_Root;
struct {
Node* front;
@@ -9230,6 +9235,14 @@
m_UsableSize = VmaPrevPow2(size);
m_SumFreeSize = m_UsableSize;
+ // Calculate m_LevelCount.
+ m_LevelCount = 1;
+ while(m_LevelCount < MAX_LEVELS &&
+ LevelToNodeSize(m_LevelCount) >= MIN_NODE_SIZE)
+ {
+ ++m_LevelCount;
+ }
+
Node* rootNode = new Node();
rootNode->offset = 0;
rootNode->type = Node::TYPE_FREE;
@@ -9252,7 +9265,7 @@
VMA_VALIDATE(m_SumFreeSize == ctx.calculatedSumFreeSize);
// Validate free node lists.
- for(uint32_t level = 0; level < MAX_LEVELS; ++level)
+ for(uint32_t level = 0; level < m_LevelCount; ++level)
{
VMA_VALIDATE(m_FreeList[level].front == VMA_NULL ||
m_FreeList[level].front->free.prev == VMA_NULL);
@@ -9274,12 +9287,18 @@
}
}
+ // Validate that free lists ar higher levels are empty.
+ for(uint32_t level = m_LevelCount; level < MAX_LEVELS; ++level)
+ {
+ VMA_VALIDATE(m_FreeList[level].front == VMA_NULL && m_FreeList[level].back == VMA_NULL);
+ }
+
return true;
}
VkDeviceSize VmaBlockMetadata_Buddy::GetUnusedRangeSizeMax() const
{
- for(uint32_t level = 0; level < MAX_LEVELS; ++level)
+ for(uint32_t level = 0; level < m_LevelCount; ++level)
{
if(m_FreeList[level].front != VMA_NULL)
{
@@ -9493,6 +9512,7 @@
bool VmaBlockMetadata_Buddy::ValidateNode(ValidationContext& ctx, const Node* parent, const Node* curr, uint32_t level, VkDeviceSize levelNodeSize) const
{
+ VMA_VALIDATE(level < m_LevelCount);
VMA_VALIDATE(curr->parent == parent);
VMA_VALIDATE((curr->buddy == VMA_NULL) == (parent == VMA_NULL));
VMA_VALIDATE(curr->buddy == VMA_NULL || curr->buddy->buddy == curr);
@@ -9540,7 +9560,7 @@
uint32_t level = 0;
VkDeviceSize currLevelNodeSize = m_UsableSize;
VkDeviceSize nextLevelNodeSize = currLevelNodeSize >> 1;
- while(allocSize <= nextLevelNodeSize && level + 1 < MAX_LEVELS)
+ while(allocSize <= nextLevelNodeSize && level + 1 < m_LevelCount)
{
++level;
currLevelNodeSize = nextLevelNodeSize;
