1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
|
#include "timestamp_pool.hh"
#include "device_context.hh"
#include "helper.hh"
#include "queue_context.hh"
#include <mutex>
#include <ranges>
#include <span>
#include <vulkan/utility/vk_dispatch_table.h>
#include <vulkan/vulkan_core.h>
namespace low_latency {
TimestampPool::QueryChunk::QueryPoolOwner::QueryPoolOwner(
const QueueContext& queue_context)
: queue_context(queue_context) {
const auto& device_context = this->queue_context.device;
const auto qpci =
VkQueryPoolCreateInfo{.sType = VK_STRUCTURE_TYPE_QUERY_POOL_CREATE_INFO,
.queryType = VK_QUERY_TYPE_TIMESTAMP,
.queryCount = QueryChunk::CHUNK_SIZE};
THROW_NOT_VKSUCCESS(device_context.vtable.CreateQueryPool(
device_context.device, &qpci, nullptr, &this->query_pool));
}
TimestampPool::QueryChunk::QueryPoolOwner::~QueryPoolOwner() {
const auto& device_context = this->queue_context.device;
device_context.vtable.DestroyQueryPool(device_context.device,
this->query_pool, nullptr);
}
TimestampPool::QueryChunk::QueryChunk(const QueueContext& queue_context)
: query_pool(std::make_unique<QueryPoolOwner>(queue_context)),
command_buffers(std::make_unique<CommandBuffersOwner>(queue_context)) {
this->free_indices = []() {
constexpr auto KEYS = std::views::iota(0u, QueryChunk::CHUNK_SIZE);
return std::make_unique<free_indices_t>(std::from_range, KEYS);
}();
}
TimestampPool::QueryChunk::CommandBuffersOwner::CommandBuffersOwner(
const QueueContext& queue_context)
: queue_context(queue_context), command_buffers(CHUNK_SIZE) {
const auto& device_context = queue_context.device;
const auto cbai = VkCommandBufferAllocateInfo{
.sType = VK_STRUCTURE_TYPE_COMMAND_BUFFER_ALLOCATE_INFO,
.commandPool = *queue_context.command_pool,
.level = VK_COMMAND_BUFFER_LEVEL_PRIMARY,
.commandBufferCount = CHUNK_SIZE,
};
THROW_NOT_VKSUCCESS(device_context.vtable.AllocateCommandBuffers(
device_context.device, &cbai, std::data(this->command_buffers)));
}
TimestampPool::QueryChunk::CommandBuffersOwner::~CommandBuffersOwner() {
const auto& device_context = this->queue_context.device;
device_context.vtable.FreeCommandBuffers(
device_context.device, *this->queue_context.command_pool,
static_cast<std::uint32_t>(std::size(this->command_buffers)),
std::data(this->command_buffers));
}
VkCommandBuffer TimestampPool::QueryChunk::CommandBuffersOwner::operator[](
const std::size_t& i) {
assert(i < CHUNK_SIZE);
return this->command_buffers[i];
}
TimestampPool::QueryChunk::~QueryChunk() {}
TimestampPool::TimestampPool(QueueContext& queue_context)
: queue_context(queue_context) {
// Allocate one block on construction, it's likely more than enough.
auto query_chunk = std::make_shared<QueryChunk>(this->queue_context);
this->query_chunks.emplace(std::move(query_chunk));
}
std::shared_ptr<TimestampPool::Handle> TimestampPool::acquire() {
const auto lock = std::scoped_lock{this->mutex};
// Gets the empty one, or inserts a new one and returns it.
const auto not_empty_iter = [this]() -> auto {
const auto not_empty_iter =
std::ranges::find_if(this->query_chunks, [](const auto& qc) {
assert(qc);
return std::size(*qc->free_indices);
});
if (not_empty_iter != std::end(this->query_chunks)) {
return not_empty_iter;
}
const auto insert = std::make_shared<QueryChunk>(this->queue_context);
const auto [iter, did_insert] = this->query_chunks.emplace(insert);
assert(did_insert);
return iter;
}();
// Grab any element from our set and erase it immediately after.
auto& indices = *(*not_empty_iter)->free_indices;
const auto query_index = *std::begin(indices);
indices.erase(query_index);
return std::make_shared<Handle>(*this, *not_empty_iter, query_index);
}
TimestampPool::Handle::Handle(TimestampPool& timestamp_pool,
const std::shared_ptr<QueryChunk>& origin_chunk,
const std::uint64_t& query_index)
: timestamp_pool(timestamp_pool), origin_chunk(origin_chunk),
query_pool(*origin_chunk->query_pool), query_index(query_index),
command_buffer((*origin_chunk->command_buffers)[query_index]) {}
TimestampPool::Handle::~Handle() {
const auto lock = std::scoped_lock{this->timestamp_pool.mutex};
// Parent destructing shouldn't mean we should have a bunch of
// insertions for zero reason.
if (const auto ptr = this->origin_chunk.lock(); ptr) {
ptr->free_indices->insert(this->query_index);
}
}
void TimestampPool::Handle::setup_command_buffers(
const Handle& tail, const QueueContext& queue_context) const {
const auto cbbi = VkCommandBufferBeginInfo{
.sType = VK_STRUCTURE_TYPE_COMMAND_BUFFER_BEGIN_INFO,
};
const auto& device_context = queue_context.device;
const auto& vtable = device_context.vtable;
vtable.ResetQueryPoolEXT(device_context.device, this->query_pool,
static_cast<std::uint32_t>(this->query_index), 1);
THROW_NOT_VKSUCCESS(vtable.ResetCommandBuffer(this->command_buffer, 0));
THROW_NOT_VKSUCCESS(vtable.BeginCommandBuffer(this->command_buffer, &cbbi));
vtable.CmdWriteTimestamp2KHR(
this->command_buffer, VK_PIPELINE_STAGE_2_TOP_OF_PIPE_BIT,
this->query_pool, static_cast<std::uint32_t>(this->query_index));
THROW_NOT_VKSUCCESS(vtable.EndCommandBuffer(this->command_buffer));
vtable.ResetQueryPoolEXT(device_context.device, tail.query_pool,
static_cast<std::uint32_t>(tail.query_index), 1);
THROW_NOT_VKSUCCESS(vtable.ResetCommandBuffer(tail.command_buffer, 0));
THROW_NOT_VKSUCCESS(vtable.BeginCommandBuffer(tail.command_buffer, &cbbi));
vtable.CmdWriteTimestamp2KHR(
tail.command_buffer, VK_PIPELINE_STAGE_2_BOTTOM_OF_PIPE_BIT,
tail.query_pool, static_cast<std::uint32_t>(tail.query_index));
THROW_NOT_VKSUCCESS(vtable.EndCommandBuffer(tail.command_buffer));
}
struct QueryResult {
std::uint64_t value;
std::uint64_t available;
};
std::optional<DeviceClock::time_point_t> TimestampPool::Handle::get_time() {
const auto& context = this->timestamp_pool.queue_context.device;
const auto& vtable = context.vtable;
auto query_result = QueryResult{};
const auto result = vtable.GetQueryPoolResults(
context.device, query_pool,
static_cast<std::uint32_t>(this->query_index), 1, sizeof(query_result),
&query_result, sizeof(query_result),
VK_QUERY_RESULT_64_BIT | VK_QUERY_RESULT_WITH_AVAILABILITY_BIT);
if (result != VK_SUCCESS && result != VK_NOT_READY) {
throw result;
}
if (!query_result.available) {
return std::nullopt;
}
return context.clock->ticks_to_time(query_result.value);
}
DeviceClock::time_point_t TimestampPool::Handle::await_time() {
const auto& context = this->timestamp_pool.queue_context.device;
const auto& vtable = context.vtable;
struct QueryResult {
std::uint64_t value;
std::uint64_t available;
};
auto query_result = QueryResult{};
THROW_NOT_VKSUCCESS(vtable.GetQueryPoolResults(
context.device, query_pool,
static_cast<std::uint32_t>(this->query_index), 1, sizeof(query_result),
&query_result, sizeof(query_result),
VK_QUERY_RESULT_64_BIT | VK_QUERY_RESULT_WITH_AVAILABILITY_BIT |
VK_QUERY_RESULT_WAIT_BIT));
assert(query_result.available);
return context.clock->ticks_to_time(query_result.value);
}
DeviceClock::time_point_t TimestampPool::Handle::get_time_required() {
const auto time = this->get_time();
assert(time.has_value());
return *time;
}
TimestampPool::~TimestampPool() {}
} // namespace low_latency
|
