libsanitizer/sanitizer_common/sanitizer_stoptheworld_mac.cpp

   1 //===-- sanitizer_stoptheworld_mac.cpp ------------------------------------===//
   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 // See sanitizer_stoptheworld.h for details.
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 #include "sanitizer_platform.h"
  14
  15 #if SANITIZER_APPLE && (defined(__x86_64__) || defined(__aarch64__) || \
  16                       defined(__i386))
  17
  18 #include <mach/mach.h>
  19 #include <mach/thread_info.h>
  20 #include <pthread.h>
  21
  22 #include "sanitizer_stoptheworld.h"
  23
  24 namespace __sanitizer {
  25 typedef struct {
  26   tid_t tid;
  27   thread_t thread;
  28 } SuspendedThreadInfo;
  29
  30 class SuspendedThreadsListMac final : public SuspendedThreadsList {
  31  public:
  32   SuspendedThreadsListMac() = default;
  33
  34   tid_t GetThreadID(uptr index) const override;
  35   thread_t GetThread(uptr index) const;
  36   uptr ThreadCount() const override;
  37   bool ContainsThread(thread_t thread) const;
  38   void Append(thread_t thread);
  39
  40   PtraceRegistersStatus GetRegistersAndSP(uptr index,
  41                                           InternalMmapVector<uptr> *buffer,
  42                                           uptr *sp) const override;
  43
  44  private:
  45   InternalMmapVector<SuspendedThreadInfo> threads_;
  46 };
  47
  48 struct RunThreadArgs {
  49   StopTheWorldCallback callback;
  50   void *argument;
  51 };
  52
  53 void *RunThread(void *arg) {
  54   struct RunThreadArgs *run_args = (struct RunThreadArgs *)arg;
  55   SuspendedThreadsListMac suspended_threads_list;
  56
  57   thread_array_t threads;
  58   mach_msg_type_number_t num_threads;
  59   kern_return_t err = task_threads(mach_task_self(), &threads, &num_threads);
  60   if (err != KERN_SUCCESS) {
  61     VReport(1, "Failed to get threads for task (errno %d).\n", err);
  62     return nullptr;
  63   }
  64
  65   thread_t thread_self = mach_thread_self();
  66   for (unsigned int i = 0; i < num_threads; ++i) {
  67     if (threads[i] == thread_self) continue;
  68
  69     thread_suspend(threads[i]);
  70     suspended_threads_list.Append(threads[i]);
  71   }
  72
  73   run_args->callback(suspended_threads_list, run_args->argument);
  74
  75   uptr num_suspended = suspended_threads_list.ThreadCount();
  76   for (unsigned int i = 0; i < num_suspended; ++i) {
  77     thread_resume(suspended_threads_list.GetThread(i));
  78   }
  79   return nullptr;
  80 }
  81
  82 void StopTheWorld(StopTheWorldCallback callback, void *argument) {
  83   struct RunThreadArgs arg = {callback, argument};
  84   pthread_t run_thread = (pthread_t)internal_start_thread(RunThread, &arg);
  85   internal_join_thread(run_thread);
  86 }
  87
  88 #if defined(__x86_64__)
  89 typedef x86_thread_state64_t regs_struct;
  90 #define regs_flavor x86_THREAD_STATE64
  91
  92 #define SP_REG __rsp
  93
  94 #elif defined(__aarch64__)
  95 typedef arm_thread_state64_t regs_struct;
  96 #define regs_flavor ARM_THREAD_STATE64
  97
  98 # if __DARWIN_UNIX03
  99 #  define SP_REG __sp
 100 # else
 101 #  define SP_REG sp
 102 # endif
 103
 104 #elif defined(__i386)
 105 typedef x86_thread_state32_t regs_struct;
 106 #define regs_flavor x86_THREAD_STATE32
 107
 108 #define SP_REG __esp
 109
 110 #else
 111 #error "Unsupported architecture"
 112 #endif
 113
 114 tid_t SuspendedThreadsListMac::GetThreadID(uptr index) const {
 115   CHECK_LT(index, threads_.size());
 116   return threads_[index].tid;
 117 }
 118
 119 thread_t SuspendedThreadsListMac::GetThread(uptr index) const {
 120   CHECK_LT(index, threads_.size());
 121   return threads_[index].thread;
 122 }
 123
 124 uptr SuspendedThreadsListMac::ThreadCount() const {
 125   return threads_.size();
 126 }
 127
 128 bool SuspendedThreadsListMac::ContainsThread(thread_t thread) const {
 129   for (uptr i = 0; i < threads_.size(); i++) {
 130     if (threads_[i].thread == thread) return true;
 131   }
 132   return false;
 133 }
 134
 135 void SuspendedThreadsListMac::Append(thread_t thread) {
 136   thread_identifier_info_data_t info;
 137   mach_msg_type_number_t info_count = THREAD_IDENTIFIER_INFO_COUNT;
 138   kern_return_t err = thread_info(thread, THREAD_IDENTIFIER_INFO,
 139                                   (thread_info_t)&info, &info_count);
 140   if (err != KERN_SUCCESS) {
 141     VReport(1, "Error - unable to get thread ident for a thread\n");
 142     return;
 143   }
 144   threads_.push_back({info.thread_id, thread});
 145 }
 146
 147 PtraceRegistersStatus SuspendedThreadsListMac::GetRegistersAndSP(
 148     uptr index, InternalMmapVector<uptr> *buffer, uptr *sp) const {
 149   thread_t thread = GetThread(index);
 150   regs_struct regs;
 151   int err;
 152   mach_msg_type_number_t reg_count = sizeof(regs) / sizeof(natural_t);
 153   err = thread_get_state(thread, regs_flavor, (thread_state_t)&regs,
 154                          &reg_count);
 155   if (err != KERN_SUCCESS) {
 156     VReport(1, "Error - unable to get registers for a thread\n");
 157     // MIG_ARRAY_TOO_LARGE, means that the state is too large, but it's
 158     // still safe to proceed.
 159     return err == MIG_ARRAY_TOO_LARGE ? REGISTERS_UNAVAILABLE
 160                                       : REGISTERS_UNAVAILABLE_FATAL;
 161   }
 162
 163   buffer->resize(RoundUpTo(sizeof(regs), sizeof(uptr)) / sizeof(uptr));
 164   internal_memcpy(buffer->data(), &regs, sizeof(regs));
 165 #if defined(__aarch64__) && defined(arm_thread_state64_get_sp)
 166   *sp = arm_thread_state64_get_sp(regs);
 167 #else
 168   *sp = regs.SP_REG;
 169 #endif
 170
 171   // On x86_64 and aarch64, we must account for the stack redzone, which is 128
 172   // bytes.
 173   if (SANITIZER_WORDSIZE == 64) *sp -= 128;
 174
 175   return REGISTERS_AVAILABLE;
 176 }
 177
 178 } // namespace __sanitizer
 179
 180 #endif  // SANITIZER_APPLE && (defined(__x86_64__) || defined(__aarch64__)) ||
 181         //                   defined(__i386))