xref: /aosp_15_r20/art/runtime/jit/profile_saver.h (revision 795d594fd825385562da6b089ea9b2033f3abf5a)
1 /*
2  * Copyright (C) 2015 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_JIT_PROFILE_SAVER_H_
18 #define ART_RUNTIME_JIT_PROFILE_SAVER_H_
19 
20 #include <utility>
21 
22 #include "app_info.h"
23 #include "base/mutex.h"
24 #include "base/safe_map.h"
25 #include "dex/method_reference.h"
26 #include "jit_code_cache.h"
27 #include "profile/profile_compilation_info.h"
28 #include "profile_saver_options.h"
29 
30 namespace art HIDDEN {
31 
32 class ProfileSaver {
33  public:
34   // Starts the profile saver thread if not already started.
35   // If the saver is already running it adds (output_filename, code_paths) to its tracked locations.
36   //
37   // The `ref_profile_filename` denotes the path to the reference profile which
38   // might be queried to determine if an initial save should be done earlier.
39   // It can be empty indicating there is no reference profile.
40   static void Start(const ProfileSaverOptions& options,
41                     const std::string& output_filename,
42                     jit::JitCodeCache* jit_code_cache,
43                     const std::vector<std::string>& code_paths,
44                     const std::string& ref_profile_filename,
45                     AppInfo::CodeType code_type)
46       REQUIRES(!Locks::profiler_lock_, !instance_->wait_lock_);
47 
48   // Stops the profile saver thread.
49   static void Stop(bool dump_info_) REQUIRES(!Locks::profiler_lock_, !instance_->wait_lock_);
50 
51   // Returns true if the profile saver is started.
52   static bool IsStarted() REQUIRES(!Locks::profiler_lock_);
53 
54   // If the profile saver is running, dumps statistics to the `os`. Otherwise it does nothing.
55   static void DumpInstanceInfo(std::ostream& os);
56 
57   static void NotifyJitActivity() REQUIRES(!Locks::profiler_lock_, !instance_->wait_lock_);
58 
59   // For testing or manual purposes (SIGUSR1).
60   EXPORT static void ForceProcessProfiles() REQUIRES(!Locks::profiler_lock_, !Locks::mutator_lock_);
61 
62   // Notify that startup has completed.
63   static void NotifyStartupCompleted() REQUIRES(!Locks::profiler_lock_, !instance_->wait_lock_);
64 
65  private:
66   // Helper classes for collecting classes and methods.
67   class GetClassesAndMethodsHelper;
68   class ScopedDefaultPriority;
69 
70   ProfileSaver(const ProfileSaverOptions& options, jit::JitCodeCache* jit_code_cache);
71   ~ProfileSaver();
72 
73   static void* RunProfileSaverThread(void* arg)
74       REQUIRES(!Locks::profiler_lock_, !instance_->wait_lock_);
75 
76   // The run loop for the saver.
77   void Run()
78       REQUIRES(Locks::profiler_lock_, !wait_lock_)
79       RELEASE(Locks::profiler_lock_);
80 
81   // Processes the existing profiling info from the jit code cache and returns
82   // true if it needed to be saved to disk.
83   // If number_of_new_methods is not null, after the call it will contain the number of new methods
84   // written to disk.
85   // If force_save is true, the saver will ignore any constraints which limit IO (e.g. will write
86   // the profile to disk even if it's just one new method).
87   bool ProcessProfilingInfo(bool force_save, /*out*/uint16_t* number_of_new_methods)
88       REQUIRES(!Locks::profiler_lock_)
89       REQUIRES(!Locks::mutator_lock_);
90 
91   void NotifyJitActivityInternal() REQUIRES(!wait_lock_);
92   void WakeUpSaver() REQUIRES(wait_lock_);
93 
94   // Returns true if the saver is shutting down (ProfileSaver::Stop() has been called).
95   bool ShuttingDown(Thread* self) REQUIRES(!Locks::profiler_lock_);
96 
97   void AddTrackedLocations(const std::string& output_filename,
98                            const std::vector<std::string>& code_paths,
99                            const std::string& ref_profile_filename,
100                            AppInfo::CodeType code_type) REQUIRES(Locks::profiler_lock_);
101 
102   // Fetches the current resolved classes and methods from the ClassLinker and stores them in the
103   // profile_cache_ for later save.
104   void FetchAndCacheResolvedClassesAndMethods(bool startup) REQUIRES(!Locks::profiler_lock_);
105 
106   void DumpInfo(std::ostream& os);
107 
108   // Resolve the realpath of the locations stored in tracked_dex_base_locations_to_be_resolved_
109   // and put the result in tracked_dex_base_locations_.
110   void ResolveTrackedLocations() REQUIRES(!Locks::profiler_lock_);
111 
112   // Get the profile metadata that should be associated with the profile session during the current
113   // profile saver session.
114   ProfileCompilationInfo::ProfileSampleAnnotation GetProfileSampleAnnotation();
115 
116   // Get extra global flags if necessary (e.g. the running architecture), otherwise 0.
117   static uint32_t GetExtraMethodHotnessFlags(const ProfileSaverOptions& options);
118 
119   // Extends the given set of flags with global flags if necessary (e.g. the running architecture).
120   ProfileCompilationInfo::MethodHotness::Flag AnnotateSampleFlags(uint32_t flags);
121 
122   // The only instance of the saver.
123   static ProfileSaver* instance_ GUARDED_BY(Locks::profiler_lock_);
124   // Profile saver thread.
125   static pthread_t profiler_pthread_ GUARDED_BY(Locks::profiler_lock_);
126 
127   jit::JitCodeCache* jit_code_cache_;
128 
129   // Collection of code paths that the profiler tracks.
130   // It maps profile locations to code paths (dex base locations).
131   SafeMap<std::string, std::set<std::string>> tracked_dex_base_locations_
132       GUARDED_BY(Locks::profiler_lock_);
133 
134   // Collection of code paths that the profiler tracks but may note have been resolved
135   // to their realpath. The resolution is done async to minimize the time it takes for
136   // someone to register a path.
137   SafeMap<std::string, std::set<std::string>> tracked_dex_base_locations_to_be_resolved_
138       GUARDED_BY(Locks::profiler_lock_);
139 
140   // Collection of output profiles that the profile tracks.
141   // It maps output profile locations to reference profiles and code types.
142   // This is used to determine if any profile is non-empty at the start of the ProfileSaver, which
143   // influences the time of the first ever save.
144   // It's also used to determine the save order.
145   SafeMap<std::string, std::pair<std::string, AppInfo::CodeType>> tracked_profiles_
146       GUARDED_BY(Locks::profiler_lock_);
147 
148   bool shutting_down_ GUARDED_BY(Locks::profiler_lock_);
149   uint64_t last_time_ns_saver_woke_up_ GUARDED_BY(wait_lock_);
150   uint32_t jit_activity_notifications_;
151 
152   // A local cache for the profile information. Maps each tracked file to its
153   // profile information. This is used to cache the startup classes so that
154   // we don't hammer the disk to save them right away.
155   // The size of this cache is usually very small and tops
156   // to just a few hundreds entries in the ProfileCompilationInfo objects.
157   SafeMap<std::string, ProfileCompilationInfo*> profile_cache_ GUARDED_BY(Locks::profiler_lock_);
158 
159   // Whether or not this is the first ever profile save.
160   // Note this is an approximation and is not 100% precise. It relies on checking
161   // whether or not the profiles are empty which is not a precise indication
162   // of being the first save (they could have been cleared in the meantime).
163   bool IsFirstSave() REQUIRES(!Locks::profiler_lock_);
164 
165   // Save period condition support.
166   Mutex wait_lock_ DEFAULT_MUTEX_ACQUIRED_AFTER;
167   ConditionVariable period_condition_ GUARDED_BY(wait_lock_);
168 
169   uint64_t total_bytes_written_;
170   uint64_t total_number_of_writes_;
171   uint64_t total_number_of_code_cache_queries_;
172   uint64_t total_number_of_skipped_writes_;
173   uint64_t total_number_of_failed_writes_;
174   uint64_t total_ms_of_sleep_;
175   uint64_t total_ns_of_work_;
176   // TODO(calin): replace with an actual size.
177   uint64_t total_number_of_hot_spikes_;
178   uint64_t total_number_of_wake_ups_;
179 
180   const ProfileSaverOptions options_;
181 
182   friend class ProfileSaverTest;
183   friend class ProfileSaverForBootTest;
184 
185   DISALLOW_COPY_AND_ASSIGN(ProfileSaver);
186 };
187 
188 }  // namespace art
189 
190 #endif  // ART_RUNTIME_JIT_PROFILE_SAVER_H_
191