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
|
// Copyright 2017 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "media/filters/frame_buffer_pool.h"
#include "base/bind.h"
#include "base/callback_helpers.h"
#include "base/location.h"
#include "base/logging.h"
#include "base/macros.h"
#include "base/sequenced_task_runner.h"
#include "base/stl_util.h"
#include "base/threading/sequenced_task_runner_handle.h"
#include "base/trace_event/memory_allocator_dump.h"
#include "base/trace_event/memory_dump_manager.h"
#include "base/trace_event/process_memory_dump.h"
namespace media {
struct FrameBufferPool::FrameBuffer {
// Not using std::vector<uint8_t> as resize() calls take a really long time
// for large buffers.
std::unique_ptr<uint8_t[]> data;
size_t data_size = 0u;
std::unique_ptr<uint8_t[]> alpha_data;
size_t alpha_data_size = 0u;
bool held_by_library = false;
// Needs to be a counter since a frame buffer might be used multiple times.
int held_by_frame = 0;
base::TimeTicks last_use_time;
};
FrameBufferPool::FrameBufferPool()
: tick_clock_(base::DefaultTickClock::GetInstance()) {
DETACH_FROM_SEQUENCE(sequence_checker_);
}
FrameBufferPool::~FrameBufferPool() {
DCHECK(in_shutdown_);
// May be destructed on any thread.
}
uint8_t* FrameBufferPool::GetFrameBuffer(size_t min_size, void** fb_priv) {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
DCHECK(!in_shutdown_);
if (!registered_dump_provider_) {
base::trace_event::MemoryDumpManager::GetInstance()
->RegisterDumpProviderWithSequencedTaskRunner(
this, "FrameBufferPool", base::SequencedTaskRunnerHandle::Get(),
MemoryDumpProvider::Options());
registered_dump_provider_ = true;
}
// Check if a free frame buffer exists.
auto it = std::find_if(
frame_buffers_.begin(), frame_buffers_.end(),
[](const std::unique_ptr<FrameBuffer>& fb) { return !IsUsed(fb.get()); });
// If not, create one.
if (it == frame_buffers_.end())
it = frame_buffers_.insert(it, std::make_unique<FrameBuffer>());
auto& frame_buffer = *it;
// Resize the frame buffer if necessary.
frame_buffer->held_by_library = true;
if (frame_buffer->data_size < min_size) {
// Free the existing |data| first so that the memory can be reused,
// if possible. Note that the new array is purposely not initialized.
frame_buffer->data.reset();
frame_buffer->data.reset(new uint8_t[min_size]);
frame_buffer->data_size = min_size;
}
// Provide the client with a private identifier.
*fb_priv = frame_buffer.get();
return frame_buffer->data.get();
}
void FrameBufferPool::ReleaseFrameBuffer(void* fb_priv) {
DCHECK(fb_priv);
// Note: The library may invoke this method multiple times for the same frame,
// so we can't DCHECK that |held_by_library| is true.
auto* frame_buffer = static_cast<FrameBuffer*>(fb_priv);
frame_buffer->held_by_library = false;
if (!IsUsed(frame_buffer))
frame_buffer->last_use_time = tick_clock_->NowTicks();
}
uint8_t* FrameBufferPool::AllocateAlphaPlaneForFrameBuffer(size_t min_size,
void* fb_priv) {
DCHECK(fb_priv);
auto* frame_buffer = static_cast<FrameBuffer*>(fb_priv);
DCHECK(IsUsed(frame_buffer));
if (frame_buffer->alpha_data_size < min_size) {
// Free the existing |alpha_data| first so that the memory can be reused,
// if possible. Note that the new array is purposely not initialized.
frame_buffer->alpha_data.reset();
frame_buffer->alpha_data.reset(new uint8_t[min_size]);
frame_buffer->alpha_data_size = min_size;
}
return frame_buffer->alpha_data.get();
}
base::Closure FrameBufferPool::CreateFrameCallback(void* fb_priv) {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
auto* frame_buffer = static_cast<FrameBuffer*>(fb_priv);
++frame_buffer->held_by_frame;
return base::Bind(&FrameBufferPool::OnVideoFrameDestroyed, this,
base::SequencedTaskRunnerHandle::Get(), frame_buffer);
}
bool FrameBufferPool::OnMemoryDump(
const base::trace_event::MemoryDumpArgs& args,
base::trace_event::ProcessMemoryDump* pmd) {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
base::trace_event::MemoryAllocatorDump* memory_dump =
pmd->CreateAllocatorDump("media/frame_buffers/memory_pool");
base::trace_event::MemoryAllocatorDump* used_memory_dump =
pmd->CreateAllocatorDump("media/frame_buffers/memory_pool/used");
pmd->AddSuballocation(memory_dump->guid(),
base::trace_event::MemoryDumpManager::GetInstance()
->system_allocator_pool_name());
size_t bytes_used = 0;
size_t bytes_reserved = 0;
for (const auto& frame_buffer : frame_buffers_) {
if (IsUsed(frame_buffer.get()))
bytes_used += frame_buffer->data_size + frame_buffer->alpha_data_size;
bytes_reserved += frame_buffer->data_size + frame_buffer->alpha_data_size;
}
memory_dump->AddScalar(base::trace_event::MemoryAllocatorDump::kNameSize,
base::trace_event::MemoryAllocatorDump::kUnitsBytes,
bytes_reserved);
used_memory_dump->AddScalar(
base::trace_event::MemoryAllocatorDump::kNameSize,
base::trace_event::MemoryAllocatorDump::kUnitsBytes, bytes_used);
return true;
}
void FrameBufferPool::Shutdown() {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
in_shutdown_ = true;
if (registered_dump_provider_) {
base::trace_event::MemoryDumpManager::GetInstance()->UnregisterDumpProvider(
this);
}
// Clear any refs held by the library which isn't good about cleaning up after
// itself. This is safe since the library has already been shutdown by this
// point.
for (const auto& frame_buffer : frame_buffers_)
frame_buffer->held_by_library = false;
EraseUnusedResources();
}
// static
bool FrameBufferPool::IsUsed(const FrameBuffer* buf) {
return buf->held_by_library || buf->held_by_frame > 0;
}
void FrameBufferPool::EraseUnusedResources() {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
base::EraseIf(frame_buffers_, [](const std::unique_ptr<FrameBuffer>& buf) {
return !IsUsed(buf.get());
});
}
void FrameBufferPool::OnVideoFrameDestroyed(
scoped_refptr<base::SequencedTaskRunner> task_runner,
FrameBuffer* frame_buffer) {
if (!task_runner->RunsTasksInCurrentSequence()) {
task_runner->PostTask(
FROM_HERE, base::Bind(&FrameBufferPool::OnVideoFrameDestroyed, this,
task_runner, frame_buffer));
return;
}
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
DCHECK_GT(frame_buffer->held_by_frame, 0);
--frame_buffer->held_by_frame;
if (in_shutdown_) {
// If we're in shutdown we can be sure that the library has been destroyed.
EraseUnusedResources();
return;
}
const base::TimeTicks now = tick_clock_->NowTicks();
if (!IsUsed(frame_buffer))
frame_buffer->last_use_time = now;
base::EraseIf(frame_buffers_, [now](const std::unique_ptr<FrameBuffer>& buf) {
return !IsUsed(buf.get()) &&
now - buf->last_use_time >
base::TimeDelta::FromSeconds(kStaleFrameLimitSecs);
});
}
} // namespace media
|
