commit 5869a2c27ee0dbd7b420614c76ff14a706f0c5fb
author Mathieu Chartier <mathieuc@google.com> Wed Oct 08 14:26:23 2014 -0700
committer Mathieu Chartier <mathieuc@google.com> Wed Oct 08 14:26:23 2014 -0700
tree 39bb17a7ae4a4d6c1db99d1a5e07ede899da0aec
parent f1f05d303988a5c071c87b760056be8358276c94

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.

(cherry picked from commit f924d2381a5ea53967ba1e279766d601b9be05ea)

Bug: 17837911
Change-Id: I3417156a78f574076d5da17c86836c5a7c76084a

runtime/base/mutex.cc

diff --git a/runtime/base/mutex.cc b/runtime/base/mutex.cc
index 4383a7c..cbcd408 100644
--- a/runtime/base/mutex.cc
+++ b/runtime/base/mutex.cc
@@ -648,7 +648,13 @@
 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 ec5b775..53c2859 100644
--- a/runtime/thread_list.cc
+++ b/runtime/thread_list.cc
@@ -199,6 +199,8 @@
   Runtime* runtime = Runtime::Current();
   std::ostringstream ss;
   ss << "Thread suspend timeout\n";
+  Locks::mutator_lock_->Dump(ss);
+  ss << "\n";
   runtime->GetThreadList()->Dump(ss);
   LOG(FATAL) << ss.str();
   exit(0);