1 /*
2 * Copyright 2014 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8 #ifndef GrResourceKey_DEFINED
9 #define GrResourceKey_DEFINED
10
11 #include "include/core/SkData.h"
12 #include "include/core/SkString.h"
13 #include "include/gpu/GrTypes.h"
14 #include "include/private/SkOnce.h"
15 #include "include/private/SkTemplates.h"
16 #include "include/private/SkTo.h"
17
18 #include <new>
19
20 uint32_t GrResourceKeyHash(const uint32_t* data, size_t size);
21
22 /**
23 * Base class for all GrGpuResource cache keys. There are two types of cache keys. Refer to the
24 * comments for each key type below.
25 */
26 class GrResourceKey {
27 public:
hash()28 uint32_t hash() const {
29 this->validate();
30 return fKey[kHash_MetaDataIdx];
31 }
32
size()33 size_t size() const {
34 this->validate();
35 SkASSERT(this->isValid());
36 return this->internalSize();
37 }
38
39 /** Used to initialize a key. */
40 class Builder {
41 public:
~Builder()42 ~Builder() { this->finish(); }
43
finish()44 void finish() {
45 if (nullptr == fKey) {
46 return;
47 }
48 uint32_t* hash = &fKey->fKey[kHash_MetaDataIdx];
49 *hash = GrResourceKeyHash(hash + 1, fKey->internalSize() - sizeof(uint32_t));
50 fKey->validate();
51 fKey = nullptr;
52 }
53
54 uint32_t& operator[](int dataIdx) {
55 SkASSERT(fKey);
56 SkDEBUGCODE(size_t dataCount = fKey->internalSize() / sizeof(uint32_t) - kMetaDataCnt;)
57 SkASSERT(SkToU32(dataIdx) < dataCount);
58 return fKey->fKey[(int)kMetaDataCnt + dataIdx];
59 }
60
61 protected:
Builder(GrResourceKey * key,uint32_t domain,int data32Count)62 Builder(GrResourceKey* key, uint32_t domain, int data32Count) : fKey(key) {
63 size_t count = SkToSizeT(data32Count);
64 SkASSERT(domain != kInvalidDomain);
65 key->fKey.reset(kMetaDataCnt + count);
66 size_t size = (count + kMetaDataCnt) * sizeof(uint32_t);
67 SkASSERT(SkToU16(size) == size);
68 SkASSERT(SkToU16(domain) == domain);
69 key->fKey[kDomainAndSize_MetaDataIdx] = domain | (size << 16);
70 }
71
72 private:
73 GrResourceKey* fKey;
74 };
75
76 protected:
77 static const uint32_t kInvalidDomain = 0;
78
GrResourceKey()79 GrResourceKey() { this->reset(); }
80
81 /** Reset to an invalid key. */
reset()82 void reset() {
83 fKey.reset(kMetaDataCnt);
84 fKey[kHash_MetaDataIdx] = 0;
85 fKey[kDomainAndSize_MetaDataIdx] = kInvalidDomain;
86 }
87
88 bool operator==(const GrResourceKey& that) const {
89 // Both keys should be sized to at least contain the meta data. The metadata contains each
90 // key's length. So the second memcmp should only run if the keys have the same length.
91 return 0 == memcmp(fKey.get(), that.fKey.get(), kMetaDataCnt*sizeof(uint32_t)) &&
92 0 == memcmp(&fKey[kMetaDataCnt], &that.fKey[kMetaDataCnt], this->dataSize());
93 }
94
95 GrResourceKey& operator=(const GrResourceKey& that) {
96 if (this != &that) {
97 if (!that.isValid()) {
98 this->reset();
99 } else {
100 size_t bytes = that.size();
101 SkASSERT(SkIsAlign4(bytes));
102 fKey.reset(bytes / sizeof(uint32_t));
103 memcpy(fKey.get(), that.fKey.get(), bytes);
104 this->validate();
105 }
106 }
107 return *this;
108 }
109
isValid()110 bool isValid() const { return kInvalidDomain != this->domain(); }
111
domain()112 uint32_t domain() const { return fKey[kDomainAndSize_MetaDataIdx] & 0xffff; }
113
114 /** size of the key data, excluding meta-data (hash, domain, etc). */
dataSize()115 size_t dataSize() const { return this->size() - 4 * kMetaDataCnt; }
116
117 /** ptr to the key data, excluding meta-data (hash, domain, etc). */
data()118 const uint32_t* data() const {
119 this->validate();
120 return &fKey[kMetaDataCnt];
121 }
122
123 #ifdef SK_DEBUG
dump()124 void dump() const {
125 if (!this->isValid()) {
126 SkDebugf("Invalid Key\n");
127 } else {
128 SkDebugf("hash: %d ", this->hash());
129 SkDebugf("domain: %d ", this->domain());
130 SkDebugf("size: %dB ", this->internalSize());
131 size_t dataCount = this->internalSize() / sizeof(uint32_t) - kMetaDataCnt;
132 for (size_t i = 0; i < dataCount; ++i) {
133 SkDebugf("%d ", fKey[SkTo<int>(kMetaDataCnt+i)]);
134 }
135 SkDebugf("\n");
136 }
137 }
138 #endif
139
140 private:
141 enum MetaDataIdx {
142 kHash_MetaDataIdx,
143 // The key domain and size are packed into a single uint32_t.
144 kDomainAndSize_MetaDataIdx,
145
146 kLastMetaDataIdx = kDomainAndSize_MetaDataIdx
147 };
148 static const uint32_t kMetaDataCnt = kLastMetaDataIdx + 1;
149
internalSize()150 size_t internalSize() const { return fKey[kDomainAndSize_MetaDataIdx] >> 16; }
151
validate()152 void validate() const {
153 SkASSERT(this->isValid());
154 SkASSERT(fKey[kHash_MetaDataIdx] ==
155 GrResourceKeyHash(&fKey[kHash_MetaDataIdx] + 1,
156 this->internalSize() - sizeof(uint32_t)));
157 SkASSERT(SkIsAlign4(this->internalSize()));
158 }
159
160 friend class TestResource; // For unit test to access kMetaDataCnt.
161
162 // bmp textures require 5 uint32_t values.
163 SkAutoSTMalloc<kMetaDataCnt + 5, uint32_t> fKey;
164 };
165
166 /**
167 * A key used for scratch resources. There are three important rules about scratch keys:
168 * * Multiple resources can share the same scratch key. Therefore resources assigned the same
169 * scratch key should be interchangeable with respect to the code that uses them.
170 * * A resource can have at most one scratch key and it is set at resource creation by the
171 * resource itself.
172 * * When a scratch resource is ref'ed it will not be returned from the
173 * cache for a subsequent cache request until all refs are released. This facilitates using
174 * a scratch key for multiple render-to-texture scenarios. An example is a separable blur:
175 *
176 * GrTexture* texture[2];
177 * texture[0] = get_scratch_texture(scratchKey);
178 * texture[1] = get_scratch_texture(scratchKey); // texture[0] is already owned so we will get a
179 * // different one for texture[1]
180 * draw_mask(texture[0], path); // draws path mask to texture[0]
181 * blur_x(texture[0], texture[1]); // blurs texture[0] in y and stores result in texture[1]
182 * blur_y(texture[1], texture[0]); // blurs texture[1] in y and stores result in texture[0]
183 * texture[1]->unref(); // texture 1 can now be recycled for the next request with scratchKey
184 * consume_blur(texture[0]);
185 * texture[0]->unref(); // texture 0 can now be recycled for the next request with scratchKey
186 */
187 class GrScratchKey : public GrResourceKey {
188 private:
189 using INHERITED = GrResourceKey;
190
191 public:
192 /** Uniquely identifies the type of resource that is cached as scratch. */
193 typedef uint32_t ResourceType;
194
195 /** Generate a unique ResourceType. */
196 static ResourceType GenerateResourceType();
197
198 /** Creates an invalid scratch key. It must be initialized using a Builder object before use. */
GrScratchKey()199 GrScratchKey() {}
200
GrScratchKey(const GrScratchKey & that)201 GrScratchKey(const GrScratchKey& that) { *this = that; }
202
203 /** reset() returns the key to the invalid state. */
204 using INHERITED::reset;
205
206 using INHERITED::isValid;
207
resourceType()208 ResourceType resourceType() const { return this->domain(); }
209
210 GrScratchKey& operator=(const GrScratchKey& that) {
211 this->INHERITED::operator=(that);
212 return *this;
213 }
214
215 bool operator==(const GrScratchKey& that) const { return this->INHERITED::operator==(that); }
216 bool operator!=(const GrScratchKey& that) const { return !(*this == that); }
217
218 class Builder : public INHERITED::Builder {
219 public:
Builder(GrScratchKey * key,ResourceType type,int data32Count)220 Builder(GrScratchKey* key, ResourceType type, int data32Count)
221 : INHERITED::Builder(key, type, data32Count) {}
222 };
223 };
224
225 /**
226 * A key that allows for exclusive use of a resource for a use case (AKA "domain"). There are three
227 * rules governing the use of unique keys:
228 * * Only one resource can have a given unique key at a time. Hence, "unique".
229 * * A resource can have at most one unique key at a time.
230 * * Unlike scratch keys, multiple requests for a unique key will return the same
231 * resource even if the resource already has refs.
232 * This key type allows a code path to create cached resources for which it is the exclusive user.
233 * The code path creates a domain which it sets on its keys. This guarantees that there are no
234 * cross-domain collisions.
235 *
236 * Unique keys preempt scratch keys. While a resource has a unique key it is inaccessible via its
237 * scratch key. It can become scratch again if the unique key is removed.
238 */
239 class GrUniqueKey : public GrResourceKey {
240 private:
241 using INHERITED = GrResourceKey;
242
243 public:
244 typedef uint32_t Domain;
245 /** Generate a Domain for unique keys. */
246 static Domain GenerateDomain();
247
248 /** Creates an invalid unique key. It must be initialized using a Builder object before use. */
GrUniqueKey()249 GrUniqueKey() : fTag(nullptr) {}
250
GrUniqueKey(const GrUniqueKey & that)251 GrUniqueKey(const GrUniqueKey& that) { *this = that; }
252
253 /** reset() returns the key to the invalid state. */
254 using INHERITED::reset;
255
256 using INHERITED::isValid;
257
258 GrUniqueKey& operator=(const GrUniqueKey& that) {
259 this->INHERITED::operator=(that);
260 this->setCustomData(sk_ref_sp(that.getCustomData()));
261 fTag = that.fTag;
262 return *this;
263 }
264
265 bool operator==(const GrUniqueKey& that) const { return this->INHERITED::operator==(that); }
266 bool operator!=(const GrUniqueKey& that) const { return !(*this == that); }
267
setCustomData(sk_sp<SkData> data)268 void setCustomData(sk_sp<SkData> data) { fData = std::move(data); }
getCustomData()269 SkData* getCustomData() const { return fData.get(); }
refCustomData()270 sk_sp<SkData> refCustomData() const { return fData; }
271
tag()272 const char* tag() const { return fTag; }
273
274 #ifdef SK_DEBUG
dump(const char * label)275 void dump(const char* label) const {
276 SkDebugf("%s tag: %s\n", label, fTag ? fTag : "None");
277 this->INHERITED::dump();
278 }
279 #endif
280
281 class Builder : public INHERITED::Builder {
282 public:
283 Builder(GrUniqueKey* key, Domain type, int data32Count, const char* tag = nullptr)
Builder(key,type,data32Count)284 : INHERITED::Builder(key, type, data32Count) {
285 key->fTag = tag;
286 }
287
288 /** Used to build a key that wraps another key and adds additional data. */
289 Builder(GrUniqueKey* key, const GrUniqueKey& innerKey, Domain domain, int extraData32Cnt,
290 const char* tag = nullptr)
291 : INHERITED::Builder(key, domain, Data32CntForInnerKey(innerKey) + extraData32Cnt) {
292 SkASSERT(&innerKey != key);
293 // add the inner key to the end of the key so that op[] can be indexed normally.
294 uint32_t* innerKeyData = &this->operator[](extraData32Cnt);
295 const uint32_t* srcData = innerKey.data();
296 (*innerKeyData++) = innerKey.domain();
297 memcpy(innerKeyData, srcData, innerKey.dataSize());
298 key->fTag = tag;
299 }
300
301 private:
Data32CntForInnerKey(const GrUniqueKey & innerKey)302 static int Data32CntForInnerKey(const GrUniqueKey& innerKey) {
303 // key data + domain
304 return SkToInt((innerKey.dataSize() >> 2) + 1);
305 }
306 };
307
308 private:
309 sk_sp<SkData> fData;
310 const char* fTag;
311 };
312
313 /**
314 * It is common to need a frequently reused GrUniqueKey where the only requirement is that the key
315 * is unique. These macros create such a key in a thread safe manner so the key can be truly global
316 * and only constructed once.
317 */
318
319 /** Place outside of function/class definitions. */
320 #define GR_DECLARE_STATIC_UNIQUE_KEY(name) static SkOnce name##_once
321
322 /** Place inside function where the key is used. */
323 #define GR_DEFINE_STATIC_UNIQUE_KEY(name) \
324 static SkAlignedSTStorage<1, GrUniqueKey> name##_storage; \
325 name##_once(gr_init_static_unique_key_once, &name##_storage); \
326 static const GrUniqueKey& name = *reinterpret_cast<GrUniqueKey*>(name##_storage.get())
327
gr_init_static_unique_key_once(SkAlignedSTStorage<1,GrUniqueKey> * keyStorage)328 static inline void gr_init_static_unique_key_once(SkAlignedSTStorage<1, GrUniqueKey>* keyStorage) {
329 GrUniqueKey* key = new (keyStorage->get()) GrUniqueKey;
330 GrUniqueKey::Builder builder(key, GrUniqueKey::GenerateDomain(), 0);
331 }
332
333 // The cache listens for these messages to purge junk resources proactively.
334 class GrUniqueKeyInvalidatedMessage {
335 public:
336 GrUniqueKeyInvalidatedMessage() = default;
337 GrUniqueKeyInvalidatedMessage(const GrUniqueKey& key, uint32_t contextUniqueID,
338 bool inThreadSafeCache = false)
fKey(key)339 : fKey(key), fContextID(contextUniqueID), fInThreadSafeCache(inThreadSafeCache) {
340 SkASSERT(SK_InvalidUniqueID != contextUniqueID);
341 }
342
343 GrUniqueKeyInvalidatedMessage(const GrUniqueKeyInvalidatedMessage&) = default;
344
345 GrUniqueKeyInvalidatedMessage& operator=(const GrUniqueKeyInvalidatedMessage&) = default;
346
key()347 const GrUniqueKey& key() const { return fKey; }
contextID()348 uint32_t contextID() const { return fContextID; }
inThreadSafeCache()349 bool inThreadSafeCache() const { return fInThreadSafeCache; }
350
351 private:
352 GrUniqueKey fKey;
353 uint32_t fContextID = SK_InvalidUniqueID;
354 bool fInThreadSafeCache = false;
355 };
356
SkShouldPostMessageToBus(const GrUniqueKeyInvalidatedMessage & msg,uint32_t msgBusUniqueID)357 static inline bool SkShouldPostMessageToBus(const GrUniqueKeyInvalidatedMessage& msg,
358 uint32_t msgBusUniqueID) {
359 return msg.contextID() == msgBusUniqueID;
360 }
361
362 #endif
363