1
2 /*
3 * Copyright 2010 Google Inc.
4 *
5 * Use of this source code is governed by a BSD-style license that can be
6 * found in the LICENSE file.
7 */
8
9
10 #include "GrBufferAllocPool.h"
11 #include "GrTypes.h"
12 #include "GrVertexBuffer.h"
13 #include "GrIndexBuffer.h"
14 #include "GrGpu.h"
15
16 #if GR_DEBUG
17 #define VALIDATE validate
18 #else
VALIDATE(bool x=false)19 static void VALIDATE(bool x = false) {}
20 #endif
21
22 // page size
23 #define GrBufferAllocPool_MIN_BLOCK_SIZE ((size_t)1 << 12)
24
GrBufferAllocPool(GrGpu * gpu,BufferType bufferType,bool frequentResetHint,size_t blockSize,int preallocBufferCnt)25 GrBufferAllocPool::GrBufferAllocPool(GrGpu* gpu,
26 BufferType bufferType,
27 bool frequentResetHint,
28 size_t blockSize,
29 int preallocBufferCnt) :
30 fBlocks(GrMax(8, 2*preallocBufferCnt)) {
31
32 GrAssert(NULL != gpu);
33 fGpu = gpu;
34 fGpu->ref();
35 fGpuIsReffed = true;
36
37 fBufferType = bufferType;
38 fFrequentResetHint = frequentResetHint;
39 fBufferPtr = NULL;
40 fMinBlockSize = GrMax(GrBufferAllocPool_MIN_BLOCK_SIZE, blockSize);
41
42 fBytesInUse = 0;
43
44 fPreallocBuffersInUse = 0;
45 fPreallocBufferStartIdx = 0;
46 for (int i = 0; i < preallocBufferCnt; ++i) {
47 GrGeometryBuffer* buffer = this->createBuffer(fMinBlockSize);
48 if (NULL != buffer) {
49 *fPreallocBuffers.append() = buffer;
50 }
51 }
52 }
53
~GrBufferAllocPool()54 GrBufferAllocPool::~GrBufferAllocPool() {
55 VALIDATE();
56 if (fBlocks.count()) {
57 GrGeometryBuffer* buffer = fBlocks.back().fBuffer;
58 if (buffer->isLocked()) {
59 buffer->unlock();
60 }
61 }
62 while (!fBlocks.empty()) {
63 destroyBlock();
64 }
65 fPreallocBuffers.unrefAll();
66 releaseGpuRef();
67 }
68
releaseGpuRef()69 void GrBufferAllocPool::releaseGpuRef() {
70 if (fGpuIsReffed) {
71 fGpu->unref();
72 fGpuIsReffed = false;
73 }
74 }
75
reset()76 void GrBufferAllocPool::reset() {
77 VALIDATE();
78 fBytesInUse = 0;
79 if (fBlocks.count()) {
80 GrGeometryBuffer* buffer = fBlocks.back().fBuffer;
81 if (buffer->isLocked()) {
82 buffer->unlock();
83 }
84 }
85 // fPreallocBuffersInUse will be decremented down to zero in the while loop
86 int preallocBuffersInUse = fPreallocBuffersInUse;
87 while (!fBlocks.empty()) {
88 this->destroyBlock();
89 }
90 if (fPreallocBuffers.count()) {
91 // must set this after above loop.
92 fPreallocBufferStartIdx = (fPreallocBufferStartIdx +
93 preallocBuffersInUse) %
94 fPreallocBuffers.count();
95 }
96 // we may have created a large cpu mirror of a large VB. Reset the size
97 // to match our pre-allocated VBs.
98 fCpuData.reset(fMinBlockSize);
99 GrAssert(0 == fPreallocBuffersInUse);
100 VALIDATE();
101 }
102
unlock()103 void GrBufferAllocPool::unlock() {
104 VALIDATE();
105
106 if (NULL != fBufferPtr) {
107 BufferBlock& block = fBlocks.back();
108 if (block.fBuffer->isLocked()) {
109 block.fBuffer->unlock();
110 } else {
111 size_t flushSize = block.fBuffer->sizeInBytes() - block.fBytesFree;
112 flushCpuData(fBlocks.back().fBuffer, flushSize);
113 }
114 fBufferPtr = NULL;
115 }
116 VALIDATE();
117 }
118
119 #if GR_DEBUG
validate(bool unusedBlockAllowed) const120 void GrBufferAllocPool::validate(bool unusedBlockAllowed) const {
121 if (NULL != fBufferPtr) {
122 GrAssert(!fBlocks.empty());
123 if (fBlocks.back().fBuffer->isLocked()) {
124 GrGeometryBuffer* buf = fBlocks.back().fBuffer;
125 GrAssert(buf->lockPtr() == fBufferPtr);
126 } else {
127 GrAssert(fCpuData.get() == fBufferPtr);
128 }
129 } else {
130 GrAssert(fBlocks.empty() || !fBlocks.back().fBuffer->isLocked());
131 }
132 size_t bytesInUse = 0;
133 for (int i = 0; i < fBlocks.count() - 1; ++i) {
134 GrAssert(!fBlocks[i].fBuffer->isLocked());
135 }
136 for (int i = 0; i < fBlocks.count(); ++i) {
137 size_t bytes = fBlocks[i].fBuffer->sizeInBytes() - fBlocks[i].fBytesFree;
138 bytesInUse += bytes;
139 GrAssert(bytes || unusedBlockAllowed);
140 }
141
142 GrAssert(bytesInUse == fBytesInUse);
143 if (unusedBlockAllowed) {
144 GrAssert((fBytesInUse && !fBlocks.empty()) ||
145 (!fBytesInUse && (fBlocks.count() < 2)));
146 } else {
147 GrAssert((0 == fBytesInUse) == fBlocks.empty());
148 }
149 }
150 #endif
151
makeSpace(size_t size,size_t alignment,const GrGeometryBuffer ** buffer,size_t * offset)152 void* GrBufferAllocPool::makeSpace(size_t size,
153 size_t alignment,
154 const GrGeometryBuffer** buffer,
155 size_t* offset) {
156 VALIDATE();
157
158 GrAssert(NULL != buffer);
159 GrAssert(NULL != offset);
160
161 if (NULL != fBufferPtr) {
162 BufferBlock& back = fBlocks.back();
163 size_t usedBytes = back.fBuffer->sizeInBytes() - back.fBytesFree;
164 size_t pad = GrSizeAlignUpPad(usedBytes,
165 alignment);
166 if ((size + pad) <= back.fBytesFree) {
167 usedBytes += pad;
168 *offset = usedBytes;
169 *buffer = back.fBuffer;
170 back.fBytesFree -= size + pad;
171 fBytesInUse += size + pad;
172 VALIDATE();
173 return (void*)(reinterpret_cast<intptr_t>(fBufferPtr) + usedBytes);
174 }
175 }
176
177 // We could honor the space request using by a partial update of the current
178 // VB (if there is room). But we don't currently use draw calls to GL that
179 // allow the driver to know that previously issued draws won't read from
180 // the part of the buffer we update. Also, the GL buffer implementation
181 // may be cheating on the actual buffer size by shrinking the buffer on
182 // updateData() if the amount of data passed is less than the full buffer
183 // size.
184
185 if (!createBlock(size)) {
186 return NULL;
187 }
188 GrAssert(NULL != fBufferPtr);
189
190 *offset = 0;
191 BufferBlock& back = fBlocks.back();
192 *buffer = back.fBuffer;
193 back.fBytesFree -= size;
194 fBytesInUse += size;
195 VALIDATE();
196 return fBufferPtr;
197 }
198
currentBufferItems(size_t itemSize) const199 int GrBufferAllocPool::currentBufferItems(size_t itemSize) const {
200 VALIDATE();
201 if (NULL != fBufferPtr) {
202 const BufferBlock& back = fBlocks.back();
203 size_t usedBytes = back.fBuffer->sizeInBytes() - back.fBytesFree;
204 size_t pad = GrSizeAlignUpPad(usedBytes, itemSize);
205 return (back.fBytesFree - pad) / itemSize;
206 } else if (fPreallocBuffersInUse < fPreallocBuffers.count()) {
207 return fMinBlockSize / itemSize;
208 }
209 return 0;
210 }
211
preallocatedBuffersRemaining() const212 int GrBufferAllocPool::preallocatedBuffersRemaining() const {
213 return fPreallocBuffers.count() - fPreallocBuffersInUse;
214 }
215
preallocatedBufferCount() const216 int GrBufferAllocPool::preallocatedBufferCount() const {
217 return fPreallocBuffers.count();
218 }
219
putBack(size_t bytes)220 void GrBufferAllocPool::putBack(size_t bytes) {
221 VALIDATE();
222
223 // if the putBack unwinds all the preallocated buffers then we will
224 // advance the starting index. As blocks are destroyed fPreallocBuffersInUse
225 // will be decremented. I will reach zero if all blocks using preallocated
226 // buffers are released.
227 int preallocBuffersInUse = fPreallocBuffersInUse;
228
229 while (bytes) {
230 // caller shouldnt try to put back more than they've taken
231 GrAssert(!fBlocks.empty());
232 BufferBlock& block = fBlocks.back();
233 size_t bytesUsed = block.fBuffer->sizeInBytes() - block.fBytesFree;
234 if (bytes >= bytesUsed) {
235 bytes -= bytesUsed;
236 fBytesInUse -= bytesUsed;
237 // if we locked a vb to satisfy the make space and we're releasing
238 // beyond it, then unlock it.
239 if (block.fBuffer->isLocked()) {
240 block.fBuffer->unlock();
241 }
242 this->destroyBlock();
243 } else {
244 block.fBytesFree += bytes;
245 fBytesInUse -= bytes;
246 bytes = 0;
247 break;
248 }
249 }
250 if (!fPreallocBuffersInUse && fPreallocBuffers.count()) {
251 fPreallocBufferStartIdx = (fPreallocBufferStartIdx +
252 preallocBuffersInUse) %
253 fPreallocBuffers.count();
254 }
255 VALIDATE();
256 }
257
createBlock(size_t requestSize)258 bool GrBufferAllocPool::createBlock(size_t requestSize) {
259
260 size_t size = GrMax(requestSize, fMinBlockSize);
261 GrAssert(size >= GrBufferAllocPool_MIN_BLOCK_SIZE);
262
263 VALIDATE();
264
265 BufferBlock& block = fBlocks.push_back();
266
267 if (size == fMinBlockSize &&
268 fPreallocBuffersInUse < fPreallocBuffers.count()) {
269
270 uint32_t nextBuffer = (fPreallocBuffersInUse +
271 fPreallocBufferStartIdx) %
272 fPreallocBuffers.count();
273 block.fBuffer = fPreallocBuffers[nextBuffer];
274 block.fBuffer->ref();
275 ++fPreallocBuffersInUse;
276 } else {
277 block.fBuffer = this->createBuffer(size);
278 if (NULL == block.fBuffer) {
279 fBlocks.pop_back();
280 return false;
281 }
282 }
283
284 block.fBytesFree = size;
285 if (NULL != fBufferPtr) {
286 GrAssert(fBlocks.count() > 1);
287 BufferBlock& prev = fBlocks.fromBack(1);
288 if (prev.fBuffer->isLocked()) {
289 prev.fBuffer->unlock();
290 } else {
291 flushCpuData(prev.fBuffer,
292 prev.fBuffer->sizeInBytes() - prev.fBytesFree);
293 }
294 fBufferPtr = NULL;
295 }
296
297 GrAssert(NULL == fBufferPtr);
298
299 if (fGpu->getCaps().bufferLockSupport() &&
300 size > GR_GEOM_BUFFER_LOCK_THRESHOLD &&
301 (!fFrequentResetHint || requestSize > GR_GEOM_BUFFER_LOCK_THRESHOLD)) {
302 fBufferPtr = block.fBuffer->lock();
303 }
304
305 if (NULL == fBufferPtr) {
306 fBufferPtr = fCpuData.reset(size);
307 }
308
309 VALIDATE(true);
310
311 return true;
312 }
313
destroyBlock()314 void GrBufferAllocPool::destroyBlock() {
315 GrAssert(!fBlocks.empty());
316
317 BufferBlock& block = fBlocks.back();
318 if (fPreallocBuffersInUse > 0) {
319 uint32_t prevPreallocBuffer = (fPreallocBuffersInUse +
320 fPreallocBufferStartIdx +
321 (fPreallocBuffers.count() - 1)) %
322 fPreallocBuffers.count();
323 if (block.fBuffer == fPreallocBuffers[prevPreallocBuffer]) {
324 --fPreallocBuffersInUse;
325 }
326 }
327 GrAssert(!block.fBuffer->isLocked());
328 block.fBuffer->unref();
329 fBlocks.pop_back();
330 fBufferPtr = NULL;
331 }
332
flushCpuData(GrGeometryBuffer * buffer,size_t flushSize)333 void GrBufferAllocPool::flushCpuData(GrGeometryBuffer* buffer,
334 size_t flushSize) {
335 GrAssert(NULL != buffer);
336 GrAssert(!buffer->isLocked());
337 GrAssert(fCpuData.get() == fBufferPtr);
338 GrAssert(flushSize <= buffer->sizeInBytes());
339 VALIDATE(true);
340
341 if (fGpu->getCaps().bufferLockSupport() &&
342 flushSize > GR_GEOM_BUFFER_LOCK_THRESHOLD) {
343 void* data = buffer->lock();
344 if (NULL != data) {
345 memcpy(data, fBufferPtr, flushSize);
346 buffer->unlock();
347 return;
348 }
349 }
350 buffer->updateData(fBufferPtr, flushSize);
351 VALIDATE(true);
352 }
353
createBuffer(size_t size)354 GrGeometryBuffer* GrBufferAllocPool::createBuffer(size_t size) {
355 if (kIndex_BufferType == fBufferType) {
356 return fGpu->createIndexBuffer(size, true);
357 } else {
358 GrAssert(kVertex_BufferType == fBufferType);
359 return fGpu->createVertexBuffer(size, true);
360 }
361 }
362
363 ////////////////////////////////////////////////////////////////////////////////
364
GrVertexBufferAllocPool(GrGpu * gpu,bool frequentResetHint,size_t bufferSize,int preallocBufferCnt)365 GrVertexBufferAllocPool::GrVertexBufferAllocPool(GrGpu* gpu,
366 bool frequentResetHint,
367 size_t bufferSize,
368 int preallocBufferCnt)
369 : GrBufferAllocPool(gpu,
370 kVertex_BufferType,
371 frequentResetHint,
372 bufferSize,
373 preallocBufferCnt) {
374 }
375
makeSpace(size_t vertexSize,int vertexCount,const GrVertexBuffer ** buffer,int * startVertex)376 void* GrVertexBufferAllocPool::makeSpace(size_t vertexSize,
377 int vertexCount,
378 const GrVertexBuffer** buffer,
379 int* startVertex) {
380
381 GrAssert(vertexCount >= 0);
382 GrAssert(NULL != buffer);
383 GrAssert(NULL != startVertex);
384
385 size_t offset = 0; // assign to suppress warning
386 const GrGeometryBuffer* geomBuffer = NULL; // assign to suppress warning
387 void* ptr = INHERITED::makeSpace(vertexSize * vertexCount,
388 vertexSize,
389 &geomBuffer,
390 &offset);
391
392 *buffer = (const GrVertexBuffer*) geomBuffer;
393 GrAssert(0 == offset % vertexSize);
394 *startVertex = offset / vertexSize;
395 return ptr;
396 }
397
appendVertices(size_t vertexSize,int vertexCount,const void * vertices,const GrVertexBuffer ** buffer,int * startVertex)398 bool GrVertexBufferAllocPool::appendVertices(size_t vertexSize,
399 int vertexCount,
400 const void* vertices,
401 const GrVertexBuffer** buffer,
402 int* startVertex) {
403 void* space = makeSpace(vertexSize, vertexCount, buffer, startVertex);
404 if (NULL != space) {
405 memcpy(space,
406 vertices,
407 vertexSize * vertexCount);
408 return true;
409 } else {
410 return false;
411 }
412 }
413
preallocatedBufferVertices(size_t vertexSize) const414 int GrVertexBufferAllocPool::preallocatedBufferVertices(size_t vertexSize) const {
415 return INHERITED::preallocatedBufferSize() / vertexSize;
416 }
417
currentBufferVertices(size_t vertexSize) const418 int GrVertexBufferAllocPool::currentBufferVertices(size_t vertexSize) const {
419 return currentBufferItems(vertexSize);
420 }
421
422 ////////////////////////////////////////////////////////////////////////////////
423
GrIndexBufferAllocPool(GrGpu * gpu,bool frequentResetHint,size_t bufferSize,int preallocBufferCnt)424 GrIndexBufferAllocPool::GrIndexBufferAllocPool(GrGpu* gpu,
425 bool frequentResetHint,
426 size_t bufferSize,
427 int preallocBufferCnt)
428 : GrBufferAllocPool(gpu,
429 kIndex_BufferType,
430 frequentResetHint,
431 bufferSize,
432 preallocBufferCnt) {
433 }
434
makeSpace(int indexCount,const GrIndexBuffer ** buffer,int * startIndex)435 void* GrIndexBufferAllocPool::makeSpace(int indexCount,
436 const GrIndexBuffer** buffer,
437 int* startIndex) {
438
439 GrAssert(indexCount >= 0);
440 GrAssert(NULL != buffer);
441 GrAssert(NULL != startIndex);
442
443 size_t offset = 0; // assign to suppress warning
444 const GrGeometryBuffer* geomBuffer = NULL; // assign to suppress warning
445 void* ptr = INHERITED::makeSpace(indexCount * sizeof(uint16_t),
446 sizeof(uint16_t),
447 &geomBuffer,
448 &offset);
449
450 *buffer = (const GrIndexBuffer*) geomBuffer;
451 GrAssert(0 == offset % sizeof(uint16_t));
452 *startIndex = offset / sizeof(uint16_t);
453 return ptr;
454 }
455
appendIndices(int indexCount,const void * indices,const GrIndexBuffer ** buffer,int * startIndex)456 bool GrIndexBufferAllocPool::appendIndices(int indexCount,
457 const void* indices,
458 const GrIndexBuffer** buffer,
459 int* startIndex) {
460 void* space = makeSpace(indexCount, buffer, startIndex);
461 if (NULL != space) {
462 memcpy(space, indices, sizeof(uint16_t) * indexCount);
463 return true;
464 } else {
465 return false;
466 }
467 }
468
preallocatedBufferIndices() const469 int GrIndexBufferAllocPool::preallocatedBufferIndices() const {
470 return INHERITED::preallocatedBufferSize() / sizeof(uint16_t);
471 }
472
currentBufferIndices() const473 int GrIndexBufferAllocPool::currentBufferIndices() const {
474 return currentBufferItems(sizeof(uint16_t));
475 }
476