1 /*
2  * Copyright (C) 2014 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 #ifndef ART_RUNTIME_GC_GC_CAUSE_H_
18 #define ART_RUNTIME_GC_GC_CAUSE_H_
19 
20 #include <iosfwd>
21 
22 namespace art {
23 namespace gc {
24 
25 // What caused the GC?
26 enum GcCause {
27   // GC triggered by a failed allocation. Thread doing allocation is blocked waiting for GC before
28   // retrying allocation.
29   kGcCauseForAlloc,
30   // A background GC trying to ensure there is free memory ahead of allocations.
31   kGcCauseBackground,
32   // An explicit System.gc() call.
33   kGcCauseExplicit,
34   // GC triggered for a native allocation.
35   kGcCauseForNativeAlloc,
36   // GC triggered for a collector transition.
37   kGcCauseCollectorTransition,
38   // Not a real GC cause, used when we disable moving GC (currently for GetPrimitiveArrayCritical).
39   kGcCauseDisableMovingGc,
40   // Not a real GC cause, used when we trim the heap.
41   kGcCauseTrim,
42   // Not a real GC cause, used to implement exclusion between GC and instrumentation.
43   kGcCauseInstrumentation,
44   // Not a real GC cause, used to add or remove app image spaces.
45   kGcCauseAddRemoveAppImageSpace,
46   // GC triggered for background transition when both foreground and background collector are CMS.
47   kGcCauseHomogeneousSpaceCompact,
48   // Class linker cause, used to guard filling art methods with special values.
49   kGcCauseClassLinker,
50 };
51 
52 const char* PrettyCause(GcCause cause);
53 std::ostream& operator<<(std::ostream& os, const GcCause& gc_cause);
54 
55 }  // namespace gc
56 }  // namespace art
57 
58 #endif  // ART_RUNTIME_GC_GC_CAUSE_H_
59