[tsan] Properly describe GCD worker threads in reports

When dealing with GCD worker threads, TSan currently prints weird things like "created by thread T-1" and "[failed to restore the stack]" in reports. This patch avoids that and instead prints "Thread T3 (...) is a GCD worker thread".

Differential Revision: https://reviews.llvm.org/D29103



git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@293882 91177308-0d34-0410-b5e6-96231b3b80d8

9 files changed, 19 insertions, 11 deletions

diff --git a/lib/tsan/go/tsan_go.cc b/lib/tsan/go/tsan_go.cc
index 34625c8af..7fb4eb2a5 100644
--- a/lib/tsan/go/tsan_go.cc
+++ b/lib/tsan/go/tsan_go.cc
@@ -214,7 +214,7 @@ void __tsan_go_start(ThreadState *parent, ThreadState **pthr, void *pc) {
   ThreadState *thr = AllocGoroutine();
   *pthr = thr;
   int goid = ThreadCreate(parent, (uptr)pc, 0, true);
-  ThreadStart(thr, goid, 0);
+  ThreadStart(thr, goid, 0, /*workerthread*/ false);
 }
 
 void __tsan_go_end(ThreadState *thr) {
diff --git a/lib/tsan/rtl/tsan_interceptors.cc b/lib/tsan/rtl/tsan_interceptors.cc
index 898f32df1..9bf1b28b9 100644
--- a/lib/tsan/rtl/tsan_interceptors.cc
+++ b/lib/tsan/rtl/tsan_interceptors.cc
@@ -881,7 +881,7 @@ extern "C" void *__tsan_thread_start_func(void *arg) {
       internal_sched_yield();
     Processor *proc = ProcCreate();
     ProcWire(proc, thr);
-    ThreadStart(thr, tid, GetTid());
+    ThreadStart(thr, tid, GetTid(), /*workerthread*/ false);
     atomic_store(&p->tid, 0, memory_order_release);
   }
   void *res = callback(param);
diff --git a/lib/tsan/rtl/tsan_platform_mac.cc b/lib/tsan/rtl/tsan_platform_mac.cc
index 25dd241d8..b8d3d5528 100644
--- a/lib/tsan/rtl/tsan_platform_mac.cc
+++ b/lib/tsan/rtl/tsan_platform_mac.cc
@@ -207,7 +207,7 @@ static void my_pthread_introspection_hook(unsigned int event, pthread_t thread,
       ThreadState *parent_thread_state = nullptr;  // No parent.
       int tid = ThreadCreate(parent_thread_state, 0, (uptr)thread, true);
       CHECK_NE(tid, 0);
-      ThreadStart(thr, tid, GetTid());
+      ThreadStart(thr, tid, GetTid(), /*workerthread*/ true);
     }
   } else if (event == PTHREAD_INTROSPECTION_THREAD_TERMINATE) {
     if (thread == pthread_self()) {
diff --git a/lib/tsan/rtl/tsan_report.cc b/lib/tsan/rtl/tsan_report.cc
index 07fd41208..29f5b749c 100644
--- a/lib/tsan/rtl/tsan_report.cc
+++ b/lib/tsan/rtl/tsan_report.cc
@@ -235,9 +235,15 @@ static void PrintThread(const ReportThread *rt) {
   if (rt->name && rt->name[0] != '\0')
     Printf(" '%s'", rt->name);
   char thrbuf[kThreadBufSize];
-  Printf(" (tid=%zu, %s) created by %s",
-    rt->os_id, rt->running ? "running" : "finished",
-    thread_name(thrbuf, rt->parent_tid));
+  const char *thread_status = rt->running ? "running" : "finished";
+  if (rt->workerthread) {
+    Printf(" (tid=%zu, %s) is a GCD worker thread\n", rt->os_id, thread_status);
+    Printf("\n");
+    Printf("%s", d.EndThreadDescription());
+    return;
+  }
+  Printf(" (tid=%zu, %s) created by %s", rt->os_id, thread_status,
+         thread_name(thrbuf, rt->parent_tid));
   if (rt->stack)
     Printf(" at:");
   Printf("\n");
diff --git a/lib/tsan/rtl/tsan_report.h b/lib/tsan/rtl/tsan_report.h
index d0b9d7458..32b79d76a 100644
--- a/lib/tsan/rtl/tsan_report.h
+++ b/lib/tsan/rtl/tsan_report.h
@@ -89,8 +89,9 @@ struct ReportThread {
   int id;
   uptr os_id;
   bool running;
+  bool workerthread;
   char *name;
-  int parent_tid;
+  u32 parent_tid;
   ReportStack *stack;
 };
 
diff --git a/lib/tsan/rtl/tsan_rtl.cc b/lib/tsan/rtl/tsan_rtl.cc
index e743a65a5..bc5991c6e 100644
--- a/lib/tsan/rtl/tsan_rtl.cc
+++ b/lib/tsan/rtl/tsan_rtl.cc
@@ -381,7 +381,7 @@ void Initialize(ThreadState *thr) {
   // Initialize thread 0.
   int tid = ThreadCreate(thr, 0, 0, true);
   CHECK_EQ(tid, 0);
-  ThreadStart(thr, tid, GetTid());
+  ThreadStart(thr, tid, GetTid(), /*workerthread*/ false);
 #if TSAN_CONTAINS_UBSAN
   __ubsan::InitAsPlugin();
 #endif
diff --git a/lib/tsan/rtl/tsan_rtl.h b/lib/tsan/rtl/tsan_rtl.h
index 7fcb9d48e..531fb8225 100644
--- a/lib/tsan/rtl/tsan_rtl.h
+++ b/lib/tsan/rtl/tsan_rtl.h
@@ -713,7 +713,7 @@ void FuncEntry(ThreadState *thr, uptr pc);
 void FuncExit(ThreadState *thr);
 
 int ThreadCreate(ThreadState *thr, uptr pc, uptr uid, bool detached);
-void ThreadStart(ThreadState *thr, int tid, uptr os_id);
+void ThreadStart(ThreadState *thr, int tid, uptr os_id, bool workerthread);
 void ThreadFinish(ThreadState *thr);
 int ThreadTid(ThreadState *thr, uptr pc, uptr uid);
 void ThreadJoin(ThreadState *thr, uptr pc, int tid);
diff --git a/lib/tsan/rtl/tsan_rtl_report.cc b/lib/tsan/rtl/tsan_rtl_report.cc
index bc8944fbf..cfb492770 100644
--- a/lib/tsan/rtl/tsan_rtl_report.cc
+++ b/lib/tsan/rtl/tsan_rtl_report.cc
@@ -202,6 +202,7 @@ void ScopedReport::AddThread(const ThreadContext *tctx, bool suppressable) {
   rt->running = (tctx->status == ThreadStatusRunning);
   rt->name = internal_strdup(tctx->name);
   rt->parent_tid = tctx->parent_tid;
+  rt->workerthread = tctx->workerthread;
   rt->stack = 0;
   rt->stack = SymbolizeStackId(tctx->creation_stack_id);
   if (rt->stack)
diff --git a/lib/tsan/rtl/tsan_rtl_thread.cc b/lib/tsan/rtl/tsan_rtl_thread.cc
index 5b17dc60b..7357d97a2 100644
--- a/lib/tsan/rtl/tsan_rtl_thread.cc
+++ b/lib/tsan/rtl/tsan_rtl_thread.cc
@@ -236,7 +236,7 @@ int ThreadCreate(ThreadState *thr, uptr pc, uptr uid, bool detached) {
   return tid;
 }
 
-void ThreadStart(ThreadState *thr, int tid, uptr os_id) {
+void ThreadStart(ThreadState *thr, int tid, uptr os_id, bool workerthread) {
   uptr stk_addr = 0;
   uptr stk_size = 0;
   uptr tls_addr = 0;
@@ -266,7 +266,7 @@ void ThreadStart(ThreadState *thr, int tid, uptr os_id) {
 
   ThreadRegistry *tr = ctx->thread_registry;
   OnStartedArgs args = { thr, stk_addr, stk_size, tls_addr, tls_size };
-  tr->StartThread(tid, os_id, &args);
+  tr->StartThread(tid, os_id, workerthread, &args);
 
   tr->Lock();
   thr->tctx = (ThreadContext*)tr->GetThreadLocked(tid);