1 //===-- memprof_thread.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 MemProfiler, a memory profiler. 10 // 11 // MemProf-private header for memprof_thread.cpp. 12 //===----------------------------------------------------------------------===// 13 14 #ifndef MEMPROF_THREAD_H 15 #define MEMPROF_THREAD_H 16 17 #include "memprof_allocator.h" 18 #include "memprof_internal.h" 19 #include "memprof_stats.h" 20 #include "sanitizer_common/sanitizer_common.h" 21 #include "sanitizer_common/sanitizer_libc.h" 22 #include "sanitizer_common/sanitizer_thread_registry.h" 23 24 namespace __sanitizer { 25 struct DTLS; 26 } // namespace __sanitizer 27 28 namespace __memprof { 29 30 class MemprofThread; 31 32 // These objects are created for every thread and are never deleted, 33 // so we can find them by tid even if the thread is long dead. 34 struct MemprofThreadContext final : public ThreadContextBase { MemprofThreadContextfinal35 explicit MemprofThreadContext(int tid) 36 : ThreadContextBase(tid), announced(false), 37 destructor_iterations(GetPthreadDestructorIterations()), stack_id(0), 38 thread(nullptr) {} 39 bool announced; 40 u8 destructor_iterations; 41 u32 stack_id; 42 MemprofThread *thread; 43 44 void OnCreated(void *arg) override; 45 void OnFinished() override; 46 47 struct CreateThreadContextArgs { 48 MemprofThread *thread; 49 StackTrace *stack; 50 }; 51 }; 52 53 // MemprofThreadContext objects are never freed, so we need many of them. 54 COMPILER_CHECK(sizeof(MemprofThreadContext) <= 256); 55 56 // MemprofThread are stored in TSD and destroyed when the thread dies. 57 class MemprofThread { 58 public: 59 static MemprofThread *Create(thread_callback_t start_routine, void *arg, 60 u32 parent_tid, StackTrace *stack, 61 bool detached); 62 static void TSDDtor(void *tsd); 63 void Destroy(); 64 65 struct InitOptions; 66 void Init(const InitOptions *options = nullptr); 67 68 thread_return_t ThreadStart(tid_t os_id, 69 atomic_uintptr_t *signal_thread_is_registered); 70 71 uptr stack_top(); 72 uptr stack_bottom(); 73 uptr stack_size(); tls_begin()74 uptr tls_begin() { return tls_begin_; } tls_end()75 uptr tls_end() { return tls_end_; } dtls()76 DTLS *dtls() { return dtls_; } tid()77 u32 tid() { return context_->tid; } context()78 MemprofThreadContext *context() { return context_; } set_context(MemprofThreadContext * context)79 void set_context(MemprofThreadContext *context) { context_ = context; } 80 81 bool AddrIsInStack(uptr addr); 82 83 // True is this thread is currently unwinding stack (i.e. collecting a stack 84 // trace). Used to prevent deadlocks on platforms where libc unwinder calls 85 // malloc internally. See PR17116 for more details. isUnwinding()86 bool isUnwinding() const { return unwinding_; } setUnwinding(bool b)87 void setUnwinding(bool b) { unwinding_ = b; } 88 malloc_storage()89 MemprofThreadLocalMallocStorage &malloc_storage() { return malloc_storage_; } stats()90 MemprofStats &stats() { return stats_; } 91 92 private: 93 // NOTE: There is no MemprofThread constructor. It is allocated 94 // via mmap() and *must* be valid in zero-initialized state. 95 96 void SetThreadStackAndTls(const InitOptions *options); 97 98 struct StackBounds { 99 uptr bottom; 100 uptr top; 101 }; 102 StackBounds GetStackBounds() const; 103 104 MemprofThreadContext *context_; 105 thread_callback_t start_routine_; 106 void *arg_; 107 108 uptr stack_top_; 109 uptr stack_bottom_; 110 111 uptr tls_begin_; 112 uptr tls_end_; 113 DTLS *dtls_; 114 115 MemprofThreadLocalMallocStorage malloc_storage_; 116 MemprofStats stats_; 117 bool unwinding_; 118 }; 119 120 // Returns a single instance of registry. 121 ThreadRegistry &memprofThreadRegistry(); 122 123 // Must be called under ThreadRegistryLock. 124 MemprofThreadContext *GetThreadContextByTidLocked(u32 tid); 125 126 // Get the current thread. May return 0. 127 MemprofThread *GetCurrentThread(); 128 void SetCurrentThread(MemprofThread *t); 129 u32 GetCurrentTidOrInvalid(); 130 131 // Used to handle fork(). 132 void EnsureMainThreadIDIsCorrect(); 133 } // namespace __memprof 134 135 #endif // MEMPROF_THREAD_H 136