tsan: fix trace tests on darwin

[dvyukov]

Summary

The trace tests crashed on darwin because of some thread
initialization issues (thread initialization is somewhat
different on darwin).
Instead of starting real threads, create a new ThreadState
in the main thread. This makes the tests more unit-testy
and hopefully won't crash on darwin (there is almost no
platform-specific code involved now).
This will also help with future trace tests that will need
more than 1 thread. Creating more than 1 real thread and
dispatching test actions across multiple threads in the
required deterministic order is painful.

Depends on D110539.

[dvyukov]

fix minor build issues

[saghir]

Hi, this change seems to be breaking PowerPC buildbots:
One such bot is https://lab.llvm.org/buildbot/#/builders/57/builds/10548
Can you please take a look?

Thanks!

[saghir]

This was failing most of our buildbots, I reverted this change locally and the errors go away. I am reverting this change for now to get the buildbots back to green and give you a chance to look into it when you can.
Please feel free to reach out if you'd like any help with troubleshooting the issues that this patch was causing on PowerPC buildbots.

Thanks!

compiler-rt/lib/tsan/rtl/tsan_platform_linux.cpp

static void InitializeLongjmpXorKey() {
   // 3. xor SPs to obtain key.
   longjmp_xor_key = mangled_sp ^ sp;
 }
 #endif
 
 extern "C" void __tsan_tls_initialization() {}
 
 void ImitateTlsWrite(ThreadState *thr, uptr tls_addr, uptr tls_size) {
-  // Check that the thr object is in tls;
   const uptr thr_beg = (uptr)thr;
   const uptr thr_end = (uptr)thr + sizeof(*thr);
-  CHECK_GE(thr_beg, tls_addr);
-  CHECK_LE(thr_beg, tls_addr + tls_size);
-  CHECK_GE(thr_end, tls_addr);
-  CHECK_LE(thr_end, tls_addr + tls_size);
-  // Since the thr object is huge, skip it.
+  // ThreadState is normally allocated in TLS and is large,
+  // so we skip it. But unit tests allocate ThreadState outside of TLS.
+  if (thr_beg < tls_addr || thr_end >= tls_addr + tls_size)
+    return;
   const uptr pc = StackTrace::GetNextInstructionPc(
       reinterpret_cast<uptr>(__tsan_tls_initialization));
   MemoryRangeImitateWrite(thr, pc, tls_addr, thr_beg - tls_addr);
   MemoryRangeImitateWrite(thr, pc, thr_end, tls_addr + tls_size - thr_end);
 }
 
 // Note: this function runs with async signals enabled,
 // so it must not touch any tsan state.

compiler-rt/lib/tsan/tests/unit/tsan_trace_test.cpp

 //===-- tsan_trace_test.cpp -----------------------------------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
 // This file is a part of ThreadSanitizer (TSan), a race detector.
 //
 //===----------------------------------------------------------------------===//
 #include "tsan_trace.h"
 
 #include <pthread.h>
 
 #include "gtest/gtest.h"
 #include "tsan_rtl.h"
 
 namespace __tsan {
 
 using namespace v3;
 
 // We need to run all trace tests in a new thread,
 // so that the thread trace is empty initially.
-static void run_in_thread(void *(*f)(void *), void *arg = nullptr) {
-  pthread_t th;
-  pthread_create(&th, nullptr, f, arg);
-  pthread_join(th, nullptr);
-}
-
-#if SANITIZER_MAC
-// These tests are currently failing on Mac.
-// See https://reviews.llvm.org/D107911 for more details.
-#  define MAYBE_RestoreAccess DISABLED_RestoreAccess
-#  define MAYBE_MemoryAccessSize DISABLED_MemoryAccessSize
-#  define MAYBE_RestoreMutexLock DISABLED_RestoreMutexLock
-#  define MAYBE_MultiPart DISABLED_MultiPart
-#else
-#  define MAYBE_RestoreAccess RestoreAccess
-#  define MAYBE_MemoryAccessSize MemoryAccessSize
-#  define MAYBE_RestoreMutexLock RestoreMutexLock
-#  define MAYBE_MultiPart MultiPart
-#endif
-
-TEST(Trace, MAYBE_RestoreAccess) {
-  struct Thread {
-    static void *Func(void *arg) {
-      // A basic test with some function entry/exit events,
-      // some mutex lock/unlock events and some other distracting
-      // memory events.
-      ThreadState *thr = cur_thread();
-      TraceFunc(thr, 0x1000);
-      TraceFunc(thr, 0x1001);
-      TraceMutexLock(thr, v3::EventType::kLock, 0x4000, 0x5000, 0x6000);
-      TraceMutexLock(thr, v3::EventType::kLock, 0x4001, 0x5001, 0x6001);
-      TraceMutexUnlock(thr, 0x5000);
-      TraceFunc(thr);
-      CHECK(TryTraceMemoryAccess(thr, 0x2001, 0x3001, 8, kAccessRead));
-      TraceMutexLock(thr, v3::EventType::kRLock, 0x4002, 0x5002, 0x6002);
-      TraceFunc(thr, 0x1002);
-      CHECK(TryTraceMemoryAccess(thr, 0x2000, 0x3000, 8, kAccessRead));
-      // This is the access we want to find.
-      // The previous one is equivalent, but RestoreStack must prefer
-      // the last of the matchig accesses.
-      CHECK(TryTraceMemoryAccess(thr, 0x2002, 0x3000, 8, kAccessRead));
-      Lock lock1(&ctx->slot_mtx);
-      ThreadRegistryLock lock2(&ctx->thread_registry);
-      VarSizeStackTrace stk;
-      MutexSet mset;
-      uptr tag = kExternalTagNone;
-      bool res =
-          RestoreStack(thr->tid, v3::EventType::kAccessExt, thr->sid,
-                       thr->epoch, 0x3000, 8, kAccessRead, &stk, &mset, &tag);
-      CHECK(res);
-      CHECK_EQ(stk.size, 3);
-      CHECK_EQ(stk.trace[0], 0x1000);
-      CHECK_EQ(stk.trace[1], 0x1002);
-      CHECK_EQ(stk.trace[2], 0x2002);
-      CHECK_EQ(mset.Size(), 2);
-      CHECK_EQ(mset.Get(0).addr, 0x5001);
-      CHECK_EQ(mset.Get(0).stack_id, 0x6001);
-      CHECK_EQ(mset.Get(0).write, true);
-      CHECK_EQ(mset.Get(1).addr, 0x5002);
-      CHECK_EQ(mset.Get(1).stack_id, 0x6002);
-      CHECK_EQ(mset.Get(1).write, false);
-      CHECK_EQ(tag, kExternalTagNone);
-      return nullptr;
-    }
-  };
-  run_in_thread(Thread::Func);
+template <uptr N>
+struct ThreadArray {
+  ThreadArray() {
+    for (auto *&thr : threads) {
+      thr = static_cast<ThreadState *>(
+          MmapOrDie(sizeof(ThreadState), "ThreadState"));
+      Tid tid = ThreadCreate(cur_thread(), 0, 0, true);
+      Processor *proc = ProcCreate();
+      ProcWire(proc, thr);
+      ThreadStart(thr, tid, 0, ThreadType::Regular);
+    }
+  }
+
+  ~ThreadArray() {
+    for (uptr i = 0; i < N; i++) {
+      if (threads[i])
+        Finish(i);
+    }
+  }
+
+  void Finish(uptr i) {
+    auto *thr = threads[i];
+    threads[i] = nullptr;
+    Processor *proc = thr->proc();
+    ThreadFinish(thr);
+    ProcUnwire(proc, thr);
+    ProcDestroy(proc);
+    UnmapOrDie(thr, sizeof(ThreadState));
+  }
+
+  ThreadState *threads[N];
+  ThreadState *operator[](uptr i) { return threads[i]; }
+  ThreadState *operator->() { return threads[0]; }
+  operator ThreadState *() { return threads[0]; }
+};
+
+TEST(Trace, RestoreAccess) {
+  ThreadArray<1> thr;
+      RestoreStack(thr->tid, v3::EventType::kAccessExt, thr->sid, thr->epoch,
+                   0x3000, 8, kAccessRead, &stk, &mset, &tag);
 }
 
-TEST(Trace, MAYBE_MemoryAccessSize) {
-  struct Thread {
-    struct Params {
-      uptr access_size, offset, size;
-      bool res;
-      int type;
-    };
-    static void *Func(void *arg) {
-      // Test tracing and matching of accesses of different sizes.
-      const Params *params = static_cast<Params *>(arg);
+TEST(Trace, MemoryAccessSize) {
+  // Test tracing and matching of accesses of different sizes.
+  Params tests[] = {
+      {1, 0, 1, true},  {4, 0, 2, true},
+      {4, 2, 2, true},  {8, 3, 1, true},
+      {2, 1, 1, true},  {1, 1, 1, false},
+      {8, 5, 4, false}, {4, static_cast<uptr>(-1l), 4, false},
+  };
+  for (auto params : tests) {
+    for (int type = 0; type < 3; type++) {
+      ThreadArray<1> thr;
       Printf("access_size=%zu, offset=%zu, size=%zu, res=%d, type=%d\n",
-             params->access_size, params->offset, params->size, params->res,
-             params->type);
-      ThreadState *thr = cur_thread();
+             params.access_size, params.offset, params.size, params.res, type);
       TraceFunc(thr, 0x1000);
-      switch (params->type) {
+      switch (type) {
         case 0:
           // This should emit compressed event.
-          CHECK(TryTraceMemoryAccess(thr, 0x2000, 0x3000, params->access_size,
+          CHECK(TryTraceMemoryAccess(thr, 0x2000, 0x3000, params.access_size,
                                      kAccessRead));
           break;
         case 1:
           // This should emit full event.
-          CHECK(TryTraceMemoryAccess(thr, 0x2000000, 0x3000,
-                                     params->access_size, kAccessRead));
+          CHECK(TryTraceMemoryAccess(thr, 0x2000000, 0x3000, params.access_size,
+                                     kAccessRead));
           break;
         case 2:
-          TraceMemoryAccessRange(thr, 0x2000000, 0x3000, params->access_size,
+          TraceMemoryAccessRange(thr, 0x2000000, 0x3000, params.access_size,
                                  kAccessRead);
           break;
       }
       Lock lock1(&ctx->slot_mtx);
       ThreadRegistryLock lock2(&ctx->thread_registry);
       VarSizeStackTrace stk;
       MutexSet mset;
       uptr tag = kExternalTagNone;
       bool res = RestoreStack(thr->tid, v3::EventType::kAccessExt, thr->sid,
-                              thr->epoch, 0x3000 + params->offset, params->size,
+                              thr->epoch, 0x3000 + params.offset, params.size,
                               kAccessRead, &stk, &mset, &tag);
-      CHECK_EQ(res, params->res);
-      if (params->res) {
+      CHECK_EQ(res, params.res);
+      if (params.res) {
         CHECK_EQ(stk.size, 2);
         CHECK_EQ(stk.trace[0], 0x1000);
-        CHECK_EQ(stk.trace[1], params->type ? 0x2000000 : 0x2000);
+        CHECK_EQ(stk.trace[1], type ? 0x2000000 : 0x2000);
       }
-      return nullptr;
     }
-  };
-  Thread::Params tests[] = {
-      {1, 0, 1, true, 0},  {4, 0, 2, true, 0},
-      {4, 2, 2, true, 0},  {8, 3, 1, true, 0},
-      {2, 1, 1, true, 0},  {1, 1, 1, false, 0},
-      {8, 5, 4, false, 0}, {4, static_cast<uptr>(-1l), 4, false, 0},
-  };
-  for (auto params : tests) {
-    for (params.type = 0; params.type < 3; params.type++)
-      run_in_thread(Thread::Func, &params);
   }
 }
 
-TEST(Trace, MAYBE_RestoreMutexLock) {
-  struct Thread {
-    static void *Func(void *arg) {
-      // Check of restoration of a mutex lock event.
-      ThreadState *thr = cur_thread();
-      TraceFunc(thr, 0x1000);
-      TraceMutexLock(thr, v3::EventType::kLock, 0x4000, 0x5000, 0x6000);
-      TraceMutexLock(thr, v3::EventType::kRLock, 0x4001, 0x5001, 0x6001);
-      TraceMutexLock(thr, v3::EventType::kRLock, 0x4002, 0x5001, 0x6002);
-      Lock lock1(&ctx->slot_mtx);
-      ThreadRegistryLock lock2(&ctx->thread_registry);
-      VarSizeStackTrace stk;
-      MutexSet mset;
-      uptr tag = kExternalTagNone;
-      bool res = RestoreStack(thr->tid, v3::EventType::kLock, thr->sid,
-                              thr->epoch, 0x5001, 0, 0, &stk, &mset, &tag);
-      CHECK(res);
-      CHECK_EQ(stk.size, 2);
-      CHECK_EQ(stk.trace[0], 0x1000);
-      CHECK_EQ(stk.trace[1], 0x4002);
-      CHECK_EQ(mset.Size(), 2);
-      CHECK_EQ(mset.Get(0).addr, 0x5000);
-      CHECK_EQ(mset.Get(0).stack_id, 0x6000);
-      CHECK_EQ(mset.Get(0).write, true);
-      CHECK_EQ(mset.Get(1).addr, 0x5001);
-      CHECK_EQ(mset.Get(1).stack_id, 0x6001);
-      CHECK_EQ(mset.Get(1).write, false);
-      return nullptr;
-    }
-  };
-  run_in_thread(Thread::Func);
+TEST(Trace, RestoreMutexLock) {
+  ThreadArray<1> thr;
+  bool res = RestoreStack(thr->tid, v3::EventType::kLock, thr->sid, thr->epoch,
+                          0x5001, 0, 0, &stk, &mset, &tag);
 }
 
-TEST(Trace, MAYBE_MultiPart) {
-  struct Thread {
-    static void *Func(void *arg) {
-      // Check replay of a trace with multiple parts.
-      ThreadState *thr = cur_thread();
-      TraceFunc(thr, 0x1000);
-      TraceFunc(thr, 0x2000);
-      TraceMutexLock(thr, v3::EventType::kLock, 0x4000, 0x5000, 0x6000);
-      const uptr kEvents = 3 * sizeof(TracePart) / sizeof(v3::Event);
-      for (uptr i = 0; i < kEvents; i++) {
-        TraceFunc(thr, 0x3000);
-        TraceMutexLock(thr, v3::EventType::kLock, 0x4002, 0x5002, 0x6002);
-        TraceMutexUnlock(thr, 0x5002);
-        TraceFunc(thr);
-      }
-      TraceFunc(thr, 0x4000);
-      TraceMutexLock(thr, v3::EventType::kRLock, 0x4001, 0x5001, 0x6001);
-      CHECK(TryTraceMemoryAccess(thr, 0x2002, 0x3000, 8, kAccessRead));
-      Lock lock1(&ctx->slot_mtx);
-      ThreadRegistryLock lock2(&ctx->thread_registry);
-      VarSizeStackTrace stk;
-      MutexSet mset;
-      uptr tag = kExternalTagNone;
-      bool res =
-          RestoreStack(thr->tid, v3::EventType::kAccessExt, thr->sid,
-                       thr->epoch, 0x3000, 8, kAccessRead, &stk, &mset, &tag);
-      CHECK(res);
-      CHECK_EQ(stk.size, 4);
-      CHECK_EQ(stk.trace[0], 0x1000);
-      CHECK_EQ(stk.trace[1], 0x2000);
-      CHECK_EQ(stk.trace[2], 0x4000);
-      CHECK_EQ(stk.trace[3], 0x2002);
-      CHECK_EQ(mset.Size(), 2);
-      CHECK_EQ(mset.Get(0).addr, 0x5000);
-      CHECK_EQ(mset.Get(0).stack_id, 0x6000);
-      CHECK_EQ(mset.Get(0).write, true);
-      CHECK_EQ(mset.Get(1).addr, 0x5001);
-      CHECK_EQ(mset.Get(1).stack_id, 0x6001);
-      CHECK_EQ(mset.Get(1).write, false);
-      return nullptr;
-    }
-  };
-  run_in_thread(Thread::Func);
+TEST(Trace, MultiPart) {
+  ThreadArray<1> thr;
+      RestoreStack(thr->tid, v3::EventType::kAccessExt, thr->sid, thr->epoch,
+                   0x3000, 8, kAccessRead, &stk, &mset, &tag);
 }
 
 }  // namespace __tsan