vk_resource_manager: Add VKFencedPool interface

Handles a pool of resources protected by fences. Manages resource
overflow allocating more resources.

This class is intended to be used through inheritance.
This commit is contained in:
ReinUsesLisp 2019-02-14 13:35:03 -03:00
parent 0ffdd0a683
commit a2b6de7e9f
2 changed files with 83 additions and 0 deletions

View file

@ -3,6 +3,7 @@
// Refer to the license.txt file included.
#include <algorithm>
#include <optional>
#include "common/assert.h"
#include "common/logging/log.h"
#include "video_core/renderer_vulkan/declarations.h"
@ -121,6 +122,56 @@ void VKFenceWatch::OnFenceRemoval(VKFence* signaling_fence) {
fence = nullptr;
}
VKFencedPool::VKFencedPool(std::size_t grow_step) : grow_step{grow_step} {}
VKFencedPool::~VKFencedPool() = default;
std::size_t VKFencedPool::CommitResource(VKFence& fence) {
const auto Search = [&](std::size_t begin, std::size_t end) -> std::optional<std::size_t> {
for (std::size_t iterator = begin; iterator < end; ++iterator) {
if (watches[iterator]->TryWatch(fence)) {
// The resource is now being watched, a free resource was successfully found.
return iterator;
}
}
return {};
};
// Try to find a free resource from the hinted position to the end.
auto found = Search(free_iterator, watches.size());
if (!found) {
// Search from beginning to the hinted position.
found = Search(0, free_iterator);
if (!found) {
// Both searches failed, the pool is full; handle it.
const std::size_t free_resource = ManageOverflow();
// Watch will wait for the resource to be free.
watches[free_resource]->Watch(fence);
found = free_resource;
}
}
// Free iterator is hinted to the resource after the one that's been commited.
free_iterator = (*found + 1) % watches.size();
return *found;
}
std::size_t VKFencedPool::ManageOverflow() {
const std::size_t old_capacity = watches.size();
Grow();
// The last entry is guaranted to be free, since it's the first element of the freshly
// allocated resources.
return old_capacity;
}
void VKFencedPool::Grow() {
const std::size_t old_capacity = watches.size();
watches.resize(old_capacity + grow_step);
std::generate(watches.begin() + old_capacity, watches.end(),
[]() { return std::make_unique<VKFenceWatch>(); });
Allocate(old_capacity, old_capacity + grow_step);
}
VKResourceManager::VKResourceManager(const VKDevice& device) : device{device} {
GrowFences(FENCES_GROW_STEP);
}

View file

@ -118,6 +118,38 @@ private:
VKFence* fence{}; ///< Fence watching this resource. nullptr when the watch is free.
};
/**
* Handles a pool of resources protected by fences. Manages resource overflow allocating more
* resources.
*/
class VKFencedPool {
public:
explicit VKFencedPool(std::size_t grow_step);
virtual ~VKFencedPool();
protected:
/**
* Commits a free resource and protects it with a fence. It may allocate new resources.
* @param fence Fence that protects the commited resource.
* @returns Index of the resource commited.
*/
std::size_t CommitResource(VKFence& fence);
/// Called when a chunk of resources have to be allocated.
virtual void Allocate(std::size_t begin, std::size_t end) = 0;
private:
/// Manages pool overflow allocating new resources.
std::size_t ManageOverflow();
/// Allocates a new page of resources.
void Grow();
std::size_t grow_step = 0; ///< Number of new resources created after an overflow
std::size_t free_iterator = 0; ///< Hint to where the next free resources is likely to be found
std::vector<std::unique_ptr<VKFenceWatch>> watches; ///< Set of watched resources
};
/**
* The resource manager handles all resources that can be protected with a fence avoiding
* driver-side or GPU-side concurrent usage. Usage is documented in VKFence.