Update suspended threads info to be compatible with darwin

Summary:
On Darwin, we need to track thread and tid as separate values.
This patch splits out the implementation of the suspended threads list
to be OS-specific.

Reviewers: glider, kubamracek, kcc

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D31474

llvm-svn: 300491

compiler-rt/lib/lsan/lsan_common.cc

@@ -200,10 +200,10 @@ void ForEachExtraStackRangeCb(uptr begin, uptr end, void* arg) {
 // Scans thread data (stacks and TLS) for heap pointers.
 static void ProcessThreads(SuspendedThreadsList const &suspended_threads,
                            Frontier *frontier) {
-  InternalScopedBuffer<uptr> registers(SuspendedThreadsList::RegisterCount());
+  InternalScopedBuffer<uptr> registers(suspended_threads.RegisterCount());
   uptr registers_begin = reinterpret_cast<uptr>(registers.data());
   uptr registers_end = registers_begin + registers.size();
-  for (uptr i = 0; i < suspended_threads.thread_count(); i++) {
+  for (uptr i = 0; i < suspended_threads.ThreadCount(); i++) {
     tid_t os_id = static_cast<tid_t>(suspended_threads.GetThreadID(i));
     LOG_THREADS("Processing thread %d.\n", os_id);
     uptr stack_begin, stack_end, tls_begin, tls_end, cache_begin, cache_end;

compiler-rt/lib/sanitizer_common/sanitizer_stoptheworld.h

@@ -29,31 +29,21 @@ enum PtraceRegistersStatus {
 // register contexts.
 class SuspendedThreadsList {
  public:
-  SuspendedThreadsList()
-    : thread_ids_(1024) {}
-  tid_t GetThreadID(uptr index) const {
-    CHECK_LT(index, thread_ids_.size());
-    return thread_ids_[index];
+  SuspendedThreadsList() = default;
+
+  // Can't declare pure virtual functions in sanitizer runtimes:
+  // __cxa_pure_virtual might be unavailable. Use UNIMPLEMENTED() instead.
+  virtual PtraceRegistersStatus GetRegistersAndSP(uptr index, uptr *buffer,
+                                                  uptr *sp) const {
+    UNIMPLEMENTED();
   }
-  PtraceRegistersStatus GetRegistersAndSP(uptr index, uptr *buffer,
-                                          uptr *sp) const;
+
   // The buffer in GetRegistersAndSP should be at least this big.
-  static uptr RegisterCount();
-  uptr thread_count() const { return thread_ids_.size(); }
-  bool Contains(tid_t thread_id) const {
-    for (uptr i = 0; i < thread_ids_.size(); i++) {
-      if (thread_ids_[i] == thread_id)
-        return true;
-    }
-    return false;
-  }
-  void Append(tid_t thread_id) {
-    thread_ids_.push_back(thread_id);
-  }
+  virtual uptr RegisterCount() const { UNIMPLEMENTED(); }
+  virtual uptr ThreadCount() const { UNIMPLEMENTED(); }
+  virtual tid_t GetThreadID(uptr index) const { UNIMPLEMENTED(); }
 
  private:
-  InternalMmapVector<tid_t> thread_ids_;
-
   // Prohibit copy and assign.
   SuspendedThreadsList(const SuspendedThreadsList&);
   void operator=(const SuspendedThreadsList&);

compiler-rt/lib/sanitizer_common/sanitizer_stoptheworld_linux_libcdep.cc

@@ -82,6 +82,23 @@
 
 namespace __sanitizer {
 
+class SuspendedThreadsListLinux : public SuspendedThreadsList {
+ public:
+  SuspendedThreadsListLinux() : thread_ids_(1024) {}
+
+  tid_t GetThreadID(uptr index) const;
+  uptr ThreadCount() const;
+  bool ContainsTid(tid_t thread_id) const;
+  void Append(tid_t tid);
+
+  PtraceRegistersStatus GetRegistersAndSP(uptr index, uptr *buffer,
+                                          uptr *sp) const;
+  uptr RegisterCount() const;
+
+ private:
+  InternalMmapVector<tid_t> thread_ids_;
+};
+
 // Structure for passing arguments into the tracer thread.
 struct TracerThreadArgument {
   StopTheWorldCallback callback;
@@ -105,12 +122,12 @@ class ThreadSuspender {
   bool SuspendAllThreads();
   void ResumeAllThreads();
   void KillAllThreads();
-  SuspendedThreadsList &suspended_threads_list() {
+  SuspendedThreadsListLinux &suspended_threads_list() {
     return suspended_threads_list_;
   }
   TracerThreadArgument *arg;
  private:
-  SuspendedThreadsList suspended_threads_list_;
+  SuspendedThreadsListLinux suspended_threads_list_;
   pid_t pid_;
   bool SuspendThread(tid_t thread_id);
 };
@@ -119,8 +136,7 @@ bool ThreadSuspender::SuspendThread(tid_t tid) {
   // Are we already attached to this thread?
   // Currently this check takes linear time, however the number of threads is
   // usually small.
-  if (suspended_threads_list_.Contains(tid))
-    return false;
+  if (suspended_threads_list_.ContainsTid(tid)) return false;
   int pterrno;
   if (internal_iserror(internal_ptrace(PTRACE_ATTACH, tid, nullptr, nullptr),
                        &pterrno)) {
@@ -165,7 +181,7 @@ bool ThreadSuspender::SuspendThread(tid_t tid) {
 }
 
 void ThreadSuspender::ResumeAllThreads() {
-  for (uptr i = 0; i < suspended_threads_list_.thread_count(); i++) {
+  for (uptr i = 0; i < suspended_threads_list_.ThreadCount(); i++) {
     pid_t tid = suspended_threads_list_.GetThreadID(i);
     int pterrno;
     if (!internal_iserror(internal_ptrace(PTRACE_DETACH, tid, nullptr, nullptr),
@@ -181,7 +197,7 @@ void ThreadSuspender::ResumeAllThreads() {
 }
 
 void ThreadSuspender::KillAllThreads() {
-  for (uptr i = 0; i < suspended_threads_list_.thread_count(); i++)
+  for (uptr i = 0; i < suspended_threads_list_.ThreadCount(); i++)
     internal_ptrace(PTRACE_KILL, suspended_threads_list_.GetThreadID(i),
                     nullptr, nullptr);
 }
@@ -492,9 +508,28 @@ typedef _user_regs_struct regs_struct;
 #error "Unsupported architecture"
 #endif // SANITIZER_ANDROID && defined(__arm__)
 
-PtraceRegistersStatus SuspendedThreadsList::GetRegistersAndSP(uptr index,
-                                                              uptr *buffer,
-                                                              uptr *sp) const {
+tid_t SuspendedThreadsListLinux::GetThreadID(uptr index) const {
+  CHECK_LT(index, thread_ids_.size());
+  return thread_ids_[index];
+}
+
+uptr SuspendedThreadsListLinux::ThreadCount() const {
+  return thread_ids_.size();
+}
+
+bool SuspendedThreadsListLinux::ContainsTid(tid_t thread_id) const {
+  for (uptr i = 0; i < thread_ids_.size(); i++) {
+    if (thread_ids_[i] == thread_id) return true;
+  }
+  return false;
+}
+
+void SuspendedThreadsListLinux::Append(tid_t tid) {
+  thread_ids_.push_back(tid);
+}
+
+PtraceRegistersStatus SuspendedThreadsListLinux::GetRegistersAndSP(
+    uptr index, uptr *buffer, uptr *sp) const {
   pid_t tid = GetThreadID(index);
   regs_struct regs;
   int pterrno;
@@ -524,7 +559,7 @@ PtraceRegistersStatus SuspendedThreadsList::GetRegistersAndSP(uptr index,
   return REGISTERS_AVAILABLE;
 }
 
-uptr SuspendedThreadsList::RegisterCount() {
+uptr SuspendedThreadsListLinux::RegisterCount() const {
   return sizeof(regs_struct) / sizeof(uptr);
 }
 } // namespace __sanitizer

compiler-rt/lib/sanitizer_common/sanitizer_stoptheworld_mac.cc

@@ -16,21 +16,78 @@
 #if SANITIZER_MAC && (defined(__x86_64__) || defined(__aarch64__) || \
                       defined(__mips64) || defined(__i386))
 
+#include <mach/mach.h>
+
 #include "sanitizer_stoptheworld.h"
 
 namespace __sanitizer {
+typedef struct {
+  tid_t tid;
+  thread_t thread;
+} SuspendedThreadInfo;
+
+class SuspendedThreadsListMac : public SuspendedThreadsList {
+ public:
+  SuspendedThreadsListMac() : threads_(1024) {}
+
+  tid_t GetThreadID(uptr index) const;
+  thread_t GetThread(uptr index) const;
+  uptr ThreadCount() const;
+  bool ContainsThread(thread_t thread) const;
+  void Append(thread_t thread);
+
+  PtraceRegistersStatus GetRegistersAndSP(uptr index, uptr *buffer,
+                                          uptr *sp) const;
+  uptr RegisterCount() const;
+
+ private:
+  InternalMmapVector<SuspendedThreadInfo> threads_;
+};
+
 void StopTheWorld(StopTheWorldCallback callback, void *argument) {
   CHECK(0 && "unimplemented");
 }
 
-PtraceRegistersStatus SuspendedThreadsList::GetRegistersAndSP(uptr index,
-                                                              uptr *buffer,
-                                                              uptr *sp) const {
+tid_t SuspendedThreadsListMac::GetThreadID(uptr index) const {
+  CHECK_LT(index, threads_.size());
+  return threads_[index].tid;
+}
+
+thread_t SuspendedThreadsListMac::GetThread(uptr index) const {
+  CHECK_LT(index, threads_.size());
+  return threads_[index].thread;
+}
+
+uptr SuspendedThreadsListMac::ThreadCount() const {
+  return threads_.size();
+}
+
+bool SuspendedThreadsListMac::ContainsThread(thread_t thread) const {
+  for (uptr i = 0; i < threads_.size(); i++) {
+    if (threads_[i].thread == thread) return true;
+  }
+  return false;
+}
+
+void SuspendedThreadsListMac::Append(thread_t thread) {
+  thread_identifier_info_data_t info;
+  mach_msg_type_number_t info_count = THREAD_IDENTIFIER_INFO_COUNT;
+  kern_return_t err = thread_info(thread, THREAD_IDENTIFIER_INFO,
+                                  (thread_info_t)&info, &info_count);
+  if (err != KERN_SUCCESS) {
+    VReport(1, "Error - unable to get thread ident for a thread\n");
+    return;
+  }
+  threads_.push_back({info.thread_id, thread});
+}
+
+PtraceRegistersStatus SuspendedThreadsListMac::GetRegistersAndSP(
+    uptr index, uptr *buffer, uptr *sp) const {
   CHECK(0 && "unimplemented");
   return REGISTERS_UNAVAILABLE_FATAL;
 }
 
-uptr SuspendedThreadsList::RegisterCount() {
+uptr SuspendedThreadsListMac::RegisterCount() const {
   CHECK(0 && "unimplemented");
   return 0;
 }