1 /*
2  * Copyright (C) 2009 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include "rsObjectBase.h"
18 #include "rsContext.h"
19 #include "rsDebugHelper.h"
20 
21 namespace android {
22 namespace renderscript {
23 
24 pthread_mutex_t ObjectBase::gObjectInitMutex = PTHREAD_MUTEX_INITIALIZER;
25 
ObjectBase(Context * rsc)26 ObjectBase::ObjectBase(Context *rsc) {
27     mUserRefCount = 0;
28     mSysRefCount = 0;
29     mRSC = rsc;
30     mNext = nullptr;
31     mPrev = nullptr;
32     mDH = nullptr;
33     mName = nullptr;
34 
35     if (gDebugStacks || gDebugReferences || gDebugLeaks) {
36         mDH = new DebugHelper();
37     }
38 
39     rsAssert(rsc);
40     add();
41 
42     if (gDebugLifetime || gDebugReferences) {
43         ALOGV("ObjectBase constructed %p", this);
44     }
45 }
46 
~ObjectBase()47 ObjectBase::~ObjectBase() {
48     if (gDebugLifetime || gDebugReferences) {
49         ALOGV("ObjectBase destroyed %p   refs %i %i", this, mUserRefCount, mSysRefCount);
50     }
51 
52     if (gDebugStacks || gDebugReferences || gDebugLeaks) {
53         if (gDebugStacks || gDebugReferences) {
54             mDH->dump();
55         }
56         delete mDH;
57         mDH = nullptr;
58     }
59 
60     free(const_cast<char *>(mName));
61 
62     if (mPrev || mNext) {
63         // While the normal practice is to call remove before we call
64         // delete.  Its possible for objects without a re-use list
65         // for avoiding duplication to be created on the stack.  In those
66         // cases we need to remove ourself here.
67         asyncLock();
68         remove();
69         asyncUnlock();
70     }
71 
72     rsAssert(!mUserRefCount);
73     rsAssert(!mSysRefCount);
74 }
75 
dumpLOGV(const char * op) const76 void ObjectBase::dumpLOGV(const char *op) const {
77     if (mName) {
78         ALOGV("%s RSobj %p, name %s, refs %i,%i  links %p,%p,%p",
79              op, this, mName, mUserRefCount, mSysRefCount, mNext, mPrev, mRSC);
80     } else {
81         ALOGV("%s RSobj %p, no-name, refs %i,%i  links %p,%p,%p",
82              op, this, mUserRefCount, mSysRefCount, mNext, mPrev, mRSC);
83     }
84 }
85 
incUserRef() const86 void ObjectBase::incUserRef() const {
87     __sync_fetch_and_add(&mUserRefCount, 1);
88     if (gDebugReferences) {
89         ALOGV("ObjectBase %p incU ref %i, %i", this, mUserRefCount, mSysRefCount);
90     }
91 }
92 
incSysRef() const93 void ObjectBase::incSysRef() const {
94     __sync_fetch_and_add(&mSysRefCount, 1);
95     if (gDebugReferences) {
96         ALOGV("ObjectBase %p incS ref %i, %i", this, mUserRefCount, mSysRefCount);
97     }
98 }
99 
preDestroy() const100 void ObjectBase::preDestroy() const {
101 }
102 
freeChildren()103 bool ObjectBase::freeChildren() {
104     return false;
105 }
106 
checkDelete(const ObjectBase * ref)107 bool ObjectBase::checkDelete(const ObjectBase *ref) {
108     if (!ref) {
109         return false;
110     }
111 
112     asyncLock();
113     // This lock protects us against the non-RS threads changing
114     // the ref counts.  At this point we should be the only thread
115     // working on them.
116     if (ref->mUserRefCount || ref->mSysRefCount) {
117         asyncUnlock();
118         return false;
119     }
120 
121     ref->remove();
122     // At this point we can unlock because there should be no possible way
123     // for another thread to reference this object.
124     ref->preDestroy();
125     asyncUnlock();
126     delete ref;
127     return true;
128 }
129 
decUserRef() const130 bool ObjectBase::decUserRef() const {
131     rsAssert(mUserRefCount > 0);
132     if (gDebugReferences) {
133         ALOGV("ObjectBase %p decU ref %i, %i", this, mUserRefCount, mSysRefCount);
134         if (mUserRefCount <= 0) {
135             mDH->dump();
136         }
137     }
138 
139 
140     if ((__sync_fetch_and_sub(&mUserRefCount, 1) <= 1)) {
141         __sync_synchronize();
142         if (mSysRefCount <= 0) {
143             return checkDelete(this);
144         }
145     }
146     return false;
147 }
148 
zeroUserRef() const149 bool ObjectBase::zeroUserRef() const {
150     if (gDebugReferences) {
151         ALOGV("ObjectBase %p zeroU ref %i, %i", this, mUserRefCount, mSysRefCount);
152     }
153 
154     __sync_and_and_fetch(&mUserRefCount, 0);
155     if (mSysRefCount <= 0) {
156         return checkDelete(this);
157     }
158     return false;
159 }
160 
decSysRef() const161 bool ObjectBase::decSysRef() const {
162     if (gDebugReferences) {
163         ALOGV("ObjectBase %p decS ref %i, %i", this, mUserRefCount, mSysRefCount);
164     }
165 
166     rsAssert(mSysRefCount > 0);
167     if ((__sync_fetch_and_sub(&mSysRefCount, 1) <= 1)) {
168         __sync_synchronize();
169         if (mUserRefCount <= 0) {
170             return checkDelete(this);
171         }
172     }
173     return false;
174 }
175 
setName(const char * name)176 void ObjectBase::setName(const char *name) {
177     mName = strdup(name);
178 }
179 
setName(const char * name,uint32_t len)180 void ObjectBase::setName(const char *name, uint32_t len) {
181     char *c = (char*)calloc(len + 1, sizeof(char));
182     rsAssert(c);
183     memcpy(c, name, len);
184     mName = c;
185 }
186 
asyncLock()187 void ObjectBase::asyncLock() {
188     pthread_mutex_lock(&gObjectInitMutex);
189 }
190 
asyncUnlock()191 void ObjectBase::asyncUnlock() {
192     pthread_mutex_unlock(&gObjectInitMutex);
193 }
194 
add() const195 void ObjectBase::add() const {
196     asyncLock();
197 
198     rsAssert(!mNext);
199     rsAssert(!mPrev);
200     mNext = mRSC->mObjHead;
201     if (mRSC->mObjHead) {
202         mRSC->mObjHead->mPrev = this;
203     }
204     mRSC->mObjHead = this;
205 
206     asyncUnlock();
207 }
208 
remove() const209 void ObjectBase::remove() const {
210     if (!mRSC) {
211         rsAssert(!mPrev);
212         rsAssert(!mNext);
213         return;
214     }
215 
216     if (mRSC->mObjHead == this) {
217         mRSC->mObjHead = mNext;
218     }
219     if (mPrev) {
220         mPrev->mNext = mNext;
221     }
222     if (mNext) {
223         mNext->mPrev = mPrev;
224     }
225     mPrev = nullptr;
226     mNext = nullptr;
227 }
228 
zeroAllUserRef(Context * rsc)229 void ObjectBase::zeroAllUserRef(Context *rsc) {
230     if (gDebugReferences || gDebugLeaks) {
231         ALOGV("Forcing release of all outstanding user refs.");
232     }
233 
234     // This operation can be slow, only to be called during context cleanup.
235     const ObjectBase * o = rsc->mObjHead;
236     while (o) {
237         //ALOGE("o %p", o);
238         if (o->zeroUserRef()) {
239 #ifdef __clang_analyzer__
240             // Assure the static analyzer that we updated mObjHead. Otherwise,
241             // it complains about a use-after-free here. Needed for b/27101951.
242             if (o == rsc->mObjHead) {
243                 abort();
244             }
245 #endif
246             // deleted the object and possibly others, restart from head.
247             o = rsc->mObjHead;
248             //ALOGE("o head %p", o);
249         } else {
250             o = o->mNext;
251             //ALOGE("o next %p", o);
252         }
253     }
254 
255     if (gDebugReferences || gDebugLeaks) {
256         ALOGV("Objects remaining.");
257         dumpAll(rsc);
258     }
259 }
260 
freeAllChildren(Context * rsc)261 void ObjectBase::freeAllChildren(Context *rsc) {
262     if (gDebugReferences) {
263         ALOGV("Forcing release of all child objects.");
264     }
265 
266     // This operation can be slow, only to be called during context cleanup.
267     ObjectBase * o = (ObjectBase *)rsc->mObjHead;
268     while (o) {
269         if (o->freeChildren()) {
270             // deleted ref to self and possibly others, restart from head.
271             o = (ObjectBase *)rsc->mObjHead;
272         } else {
273             o = (ObjectBase *)o->mNext;
274         }
275     }
276 
277     if (gDebugReferences) {
278         ALOGV("Objects remaining.");
279         dumpAll(rsc);
280     }
281 }
282 
dumpAll(Context * rsc)283 void ObjectBase::dumpAll(Context *rsc) {
284     asyncLock();
285 
286     ALOGV("Dumping all objects");
287     const ObjectBase * o = rsc->mObjHead;
288     while (o) {
289         ALOGV(" Object %p", o);
290         o->dumpLOGV("  ");
291         if (o->mDH != nullptr) {
292             o->mDH->dump();
293         }
294         o = o->mNext;
295     }
296 
297     asyncUnlock();
298 }
299 
isValid(const Context * rsc,const ObjectBase * obj)300 bool ObjectBase::isValid(const Context *rsc, const ObjectBase *obj) {
301     asyncLock();
302 
303     const ObjectBase * o = rsc->mObjHead;
304     while (o) {
305         if (o == obj) {
306             asyncUnlock();
307             return true;
308         }
309         o = o->mNext;
310     }
311     asyncUnlock();
312     return false;
313 }
314 
callUpdateCacheObject(const Context * rsc,void * dstObj) const315 void ObjectBase::callUpdateCacheObject(const Context *rsc, void *dstObj) const {
316     //ALOGE("ObjectBase::callUpdateCacheObject %p  %p", this, dstObj);
317     *((const void **)dstObj) = this;
318 }
319 
320 } // namespace renderscript
321 } // namespace android
322