1//===-- sanitizer_thread_registry.h -----------------------------*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file is shared between sanitizer tools.
11//
12// General thread bookkeeping functionality.
13//===----------------------------------------------------------------------===//
14
15#ifndef SANITIZER_THREAD_REGISTRY_H
16#define SANITIZER_THREAD_REGISTRY_H
17
18#include "sanitizer_common.h"
19#include "sanitizer_list.h"
20#include "sanitizer_mutex.h"
21
22namespace __sanitizer {
23
24enum ThreadStatus {
25  ThreadStatusInvalid,   // Non-existent thread, data is invalid.
26  ThreadStatusCreated,   // Created but not yet running.
27  ThreadStatusRunning,   // The thread is currently running.
28  ThreadStatusFinished,  // Joinable thread is finished but not yet joined.
29  ThreadStatusDead       // Joined, but some info is still available.
30};
31
32// Generic thread context. Specific sanitizer tools may inherit from it.
33// If thread is dead, context may optionally be reused for a new thread.
34class ThreadContextBase {
35 public:
36  explicit ThreadContextBase(u32 tid);
37  ~ThreadContextBase();  // Should never be called.
38
39  const u32 tid;  // Thread ID. Main thread should have tid = 0.
40  u64 unique_id;  // Unique thread ID.
41  u32 reuse_count;  // Number of times this tid was reused.
42  uptr os_id;     // PID (used for reporting).
43  uptr user_id;   // Some opaque user thread id (e.g. pthread_t).
44  char name[64];  // As annotated by user.
45
46  ThreadStatus status;
47  bool detached;
48
49  u32 parent_tid;
50  ThreadContextBase *next;  // For storing thread contexts in a list.
51
52  void SetName(const char *new_name);
53
54  void SetDead();
55  void SetJoined(void *arg);
56  void SetFinished();
57  void SetStarted(uptr _os_id, void *arg);
58  void SetCreated(uptr _user_id, u64 _unique_id, bool _detached,
59                  u32 _parent_tid, void *arg);
60  void Reset();
61
62  // The following methods may be overriden by subclasses.
63  // Some of them take opaque arg that may be optionally be used
64  // by subclasses.
65  virtual void OnDead() {}
66  virtual void OnJoined(void *arg) {}
67  virtual void OnFinished() {}
68  virtual void OnStarted(void *arg) {}
69  virtual void OnCreated(void *arg) {}
70  virtual void OnReset() {}
71};
72
73typedef ThreadContextBase* (*ThreadContextFactory)(u32 tid);
74
75class ThreadRegistry {
76 public:
77  static const u32 kUnknownTid;
78
79  ThreadRegistry(ThreadContextFactory factory, u32 max_threads,
80                 u32 thread_quarantine_size, u32 max_reuse = 0);
81  void GetNumberOfThreads(uptr *total = 0, uptr *running = 0, uptr *alive = 0);
82  uptr GetMaxAliveThreads();
83
84  void Lock() { mtx_.Lock(); }
85  void CheckLocked() { mtx_.CheckLocked(); }
86  void Unlock() { mtx_.Unlock(); }
87
88  // Should be guarded by ThreadRegistryLock.
89  ThreadContextBase *GetThreadLocked(u32 tid) {
90    DCHECK_LT(tid, n_contexts_);
91    return threads_[tid];
92  }
93
94  u32 CreateThread(uptr user_id, bool detached, u32 parent_tid, void *arg);
95
96  typedef void (*ThreadCallback)(ThreadContextBase *tctx, void *arg);
97  // Invokes callback with a specified arg for each thread context.
98  // Should be guarded by ThreadRegistryLock.
99  void RunCallbackForEachThreadLocked(ThreadCallback cb, void *arg);
100
101  typedef bool (*FindThreadCallback)(ThreadContextBase *tctx, void *arg);
102  // Finds a thread using the provided callback. Returns kUnknownTid if no
103  // thread is found.
104  u32 FindThread(FindThreadCallback cb, void *arg);
105  // Should be guarded by ThreadRegistryLock. Return 0 if no thread
106  // is found.
107  ThreadContextBase *FindThreadContextLocked(FindThreadCallback cb,
108                                             void *arg);
109  ThreadContextBase *FindThreadContextByOsIDLocked(uptr os_id);
110
111  void SetThreadName(u32 tid, const char *name);
112  void SetThreadNameByUserId(uptr user_id, const char *name);
113  void DetachThread(u32 tid);
114  void JoinThread(u32 tid, void *arg);
115  void FinishThread(u32 tid);
116  void StartThread(u32 tid, uptr os_id, void *arg);
117
118 private:
119  const ThreadContextFactory context_factory_;
120  const u32 max_threads_;
121  const u32 thread_quarantine_size_;
122  const u32 max_reuse_;
123
124  BlockingMutex mtx_;
125
126  u32 n_contexts_;      // Number of created thread contexts,
127                        // at most max_threads_.
128  u64 total_threads_;   // Total number of created threads. May be greater than
129                        // max_threads_ if contexts were reused.
130  uptr alive_threads_;  // Created or running.
131  uptr max_alive_threads_;
132  uptr running_threads_;
133
134  ThreadContextBase **threads_;  // Array of thread contexts is leaked.
135  IntrusiveList<ThreadContextBase> dead_threads_;
136  IntrusiveList<ThreadContextBase> invalid_threads_;
137
138  void QuarantinePush(ThreadContextBase *tctx);
139  ThreadContextBase *QuarantinePop();
140};
141
142typedef GenericScopedLock<ThreadRegistry> ThreadRegistryLock;
143
144}  // namespace __sanitizer
145
146#endif  // SANITIZER_THREAD_REGISTRY_H
147
148