1 /* libs/pixelflinger/codeflinger/CodeCache.h
2 **
3 ** Copyright 2006, The Android Open Source Project
4 **
5 ** Licensed under the Apache License, Version 2.0 (the "License");
6 ** you may not use this file except in compliance with the License.
7 ** You may obtain a copy of the License at
8 **
9 ** http://www.apache.org/licenses/LICENSE-2.0
10 **
11 ** Unless required by applicable law or agreed to in writing, software
12 ** distributed under the License is distributed on an "AS IS" BASIS,
13 ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 ** See the License for the specific language governing permissions and
15 ** limitations under the License.
16 */
17
18
19 #ifndef ANDROID_CODECACHE_H
20 #define ANDROID_CODECACHE_H
21
22 #include <atomic>
23 #include <stdint.h>
24 #include <pthread.h>
25 #include <sys/types.h>
26
27 #include "utils/KeyedVector.h"
28 #include "tinyutils/smartpointer.h"
29
30 namespace android {
31
32 using namespace tinyutils;
33
34 // ----------------------------------------------------------------------------
35
36 class AssemblyKeyBase {
37 public:
~AssemblyKeyBase()38 virtual ~AssemblyKeyBase() { }
39 virtual int compare_type(const AssemblyKeyBase& key) const = 0;
40 };
41
42 template <typename T>
43 class AssemblyKey : public AssemblyKeyBase
44 {
45 public:
AssemblyKey(const T & rhs)46 explicit AssemblyKey(const T& rhs) : mKey(rhs) { }
compare_type(const AssemblyKeyBase & key)47 virtual int compare_type(const AssemblyKeyBase& key) const {
48 const T& rhs = static_cast<const AssemblyKey&>(key).mKey;
49 return android::compare_type(mKey, rhs);
50 }
51 private:
52 T mKey;
53 };
54
55 // ----------------------------------------------------------------------------
56
57 class Assembly
58 {
59 public:
60 explicit Assembly(size_t size);
61 virtual ~Assembly();
62
63 ssize_t size() const;
64 uint32_t* base() const;
65 ssize_t resize(size_t size);
66
67 // protocol for sp<>
68 void incStrong(const void* id) const;
69 void decStrong(const void* id) const;
70 typedef void weakref_type;
71
72 private:
73 mutable std::atomic<int32_t> mCount;
74 uint32_t* mBase;
75 size_t mSize;
76 };
77
78 // ----------------------------------------------------------------------------
79
80 class CodeCache
81 {
82 public:
83 // pretty simple cache API...
84 explicit CodeCache(size_t size);
85 ~CodeCache();
86
87 sp<Assembly> lookup(const AssemblyKeyBase& key) const;
88
89 int cache(const AssemblyKeyBase& key,
90 const sp<Assembly>& assembly);
91
92 private:
93 // nothing to see here...
94 struct cache_entry_t {
cache_entry_tcache_entry_t95 inline cache_entry_t() { }
cache_entry_tcache_entry_t96 inline cache_entry_t(const sp<Assembly>& a, int64_t w)
97 : entry(a), when(w) { }
98 sp<Assembly> entry;
99 mutable int64_t when;
100 };
101
102 class key_t {
103 friend int compare_type(
104 const key_value_pair_t<key_t, cache_entry_t>&,
105 const key_value_pair_t<key_t, cache_entry_t>&);
106 const AssemblyKeyBase* mKey;
107 public:
key_t()108 key_t() { };
key_t(const AssemblyKeyBase & k)109 explicit key_t(const AssemblyKeyBase& k) : mKey(&k) { }
110 };
111
112 mutable pthread_mutex_t mLock;
113 mutable int64_t mWhen;
114 size_t mCacheSize;
115 size_t mCacheInUse;
116 KeyedVector<key_t, cache_entry_t> mCacheData;
117
118 friend int compare_type(
119 const key_value_pair_t<key_t, cache_entry_t>&,
120 const key_value_pair_t<key_t, cache_entry_t>&);
121 };
122
123 // KeyedVector uses compare_type(), which is more efficient, than
124 // just using operator < ()
compare_type(const key_value_pair_t<CodeCache::key_t,CodeCache::cache_entry_t> & lhs,const key_value_pair_t<CodeCache::key_t,CodeCache::cache_entry_t> & rhs)125 inline int compare_type(
126 const key_value_pair_t<CodeCache::key_t, CodeCache::cache_entry_t>& lhs,
127 const key_value_pair_t<CodeCache::key_t, CodeCache::cache_entry_t>& rhs)
128 {
129 return lhs.key.mKey->compare_type(*(rhs.key.mKey));
130 }
131
132 // ----------------------------------------------------------------------------
133
134 }; // namespace android
135
136 #endif //ANDROID_CODECACHE_H
137