commit f924d2381a5ea53967ba1e279766d601b9be05ea
author Mathieu Chartier <mathieuc@google.com> Wed Oct 08 12:17:44 2014 -0700
committer Mathieu Chartier <mathieuc@google.com> Wed Oct 08 14:04:03 2014 -0700
tree 3ba4984a60d1a06cfded3e00c60e44330054a35f
parent 21b45c88759f04a178e6ee87c89f801cef7d88e1

Dump mutator lock for thread suspend timeout

Should help us see if thread suspend timeouts are due to someone
holding on the mutator lock for too long or if it is a missed
futex wake.

Bug: 17837911
Change-Id: I3417156a78f574076d5da17c86836c5a7c76084a

runtime/base/mutex.cc

diff --git a/runtime/base/mutex.cc b/runtime/base/mutex.cc
index 9b97411..495ea5c 100644
--- a/runtime/base/mutex.cc
+++ b/runtime/base/mutex.cc
@@ -647,7 +647,13 @@
 void ReaderWriterMutex::Dump(std::ostream& os) const {
   os << name_
       << " level=" << static_cast<int>(level_)
-      << " owner=" << GetExclusiveOwnerTid() << " ";
+      << " owner=" << GetExclusiveOwnerTid()
+#if ART_USE_FUTEXES
+      << " state=" << state_.LoadSequentiallyConsistent()
+      << " num_pending_writers=" << num_pending_writers_.LoadSequentiallyConsistent()
+      << " num_pending_readers=" << num_pending_readers_.LoadSequentiallyConsistent()
+#endif
+      << " ";
   DumpContention(os);
 }
 

runtime/thread_list.cc

diff --git a/runtime/thread_list.cc b/runtime/thread_list.cc
index ceed254..b4462c3 100644
--- a/runtime/thread_list.cc
+++ b/runtime/thread_list.cc
@@ -160,6 +160,8 @@
   Runtime* runtime = Runtime::Current();
   std::ostringstream ss;
   ss << "Thread suspend timeout\n";
+  Locks::mutator_lock_->Dump(ss);
+  ss << "\n";
   runtime->GetThreadList()->DumpLocked(ss);
   LOG(FATAL) << ss.str();
   exit(0);