1//===-- sanitizer_deadlock_detector_interface.h -----------------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file is a part of Sanitizer runtime.
10// Abstract deadlock detector interface.
11// FIXME: this is work in progress, nothing really works yet.
12//
13//===----------------------------------------------------------------------===//
14
15#ifndef SANITIZER_DEADLOCK_DETECTOR_INTERFACE_H
16#define SANITIZER_DEADLOCK_DETECTOR_INTERFACE_H
17
18#ifndef SANITIZER_DEADLOCK_DETECTOR_VERSION
19# define SANITIZER_DEADLOCK_DETECTOR_VERSION 1
20#endif
21
22#include "sanitizer_internal_defs.h"
23#include "sanitizer_atomic.h"
24
25namespace __sanitizer {
26
27// dd - deadlock detector.
28// lt - logical (user) thread.
29// pt - physical (OS) thread.
30
31struct DDPhysicalThread;
32struct DDLogicalThread;
33
34struct DDMutex {
35#if SANITIZER_DEADLOCK_DETECTOR_VERSION == 1
36  uptr id;
37  u32  stk;  // creation stack
38#elif SANITIZER_DEADLOCK_DETECTOR_VERSION == 2
39  u32              id;
40  u32              recursion;
41  atomic_uintptr_t owner;
42#else
43# error "BAD SANITIZER_DEADLOCK_DETECTOR_VERSION"
44#endif
45  u64  ctx;
46};
47
48struct DDFlags {
49  bool second_deadlock_stack;
50};
51
52struct DDReport {
53  enum { kMaxLoopSize = 20 };
54  int n;  // number of entries in loop
55  struct {
56    u64 thr_ctx;   // user thread context
57    u64 mtx_ctx0;  // user mutex context, start of the edge
58    u64 mtx_ctx1;  // user mutex context, end of the edge
59    u32 stk[2];  // stack ids for the edge
60  } loop[kMaxLoopSize];
61};
62
63struct DDCallback {
64  DDPhysicalThread *pt;
65  DDLogicalThread  *lt;
66
67  virtual u32 Unwind() { return 0; }
68  virtual int UniqueTid() { return 0; }
69};
70
71struct DDetector {
72  static DDetector *Create(const DDFlags *flags);
73
74  virtual DDPhysicalThread* CreatePhysicalThread() { return nullptr; }
75  virtual void DestroyPhysicalThread(DDPhysicalThread *pt) {}
76
77  virtual DDLogicalThread* CreateLogicalThread(u64 ctx) { return nullptr; }
78  virtual void DestroyLogicalThread(DDLogicalThread *lt) {}
79
80  virtual void MutexInit(DDCallback *cb, DDMutex *m) {}
81  virtual void MutexBeforeLock(DDCallback *cb, DDMutex *m, bool wlock) {}
82  virtual void MutexAfterLock(DDCallback *cb, DDMutex *m, bool wlock,
83      bool trylock) {}
84  virtual void MutexBeforeUnlock(DDCallback *cb, DDMutex *m, bool wlock) {}
85  virtual void MutexDestroy(DDCallback *cb, DDMutex *m) {}
86
87  virtual DDReport *GetReport(DDCallback *cb) { return nullptr; }
88};
89
90} // namespace __sanitizer
91
92#endif // SANITIZER_DEADLOCK_DETECTOR_INTERFACE_H
93