Inflate contended lock word by suspending owner.

Bug 6961405.
Don't inflate monitors for Notify and NotifyAll.
Tidy lock word, handle recursive lock case alongside unlocked case and move
assembly out of line (except for ARM quick). Also handle null in out-of-line
assembly as the test is quick and the enter/exit code is already a safepoint.
To gain ownership of a monitor on behalf of another thread, monitor contenders
must not hold the monitor_lock_, so they wait on a condition variable.
Reduce size of per mutex contention log.
Be consistent in calling thin lock thread ids just thread ids.
Fix potential thread death races caused by the use of FindThreadByThreadId,
make it invariant that returned threads are either self or suspended now.

Code size reduction on ARM boot.oat 0.2%.
Old nexus 7 speedup 0.25%, new nexus 7 speedup 1.4%, nexus 10 speedup 2.24%,
nexus 4 speedup 2.09% on DeltaBlue.

Change-Id: Id52558b914f160d9c8578fdd7fc8199a9598576a

1 files changed, 9 insertions, 1 deletions

diff --git a/runtime/runtime.cc b/runtime/runtime.cc
index b4ce37f..8a20bbc 100644
--- a/runtime/runtime.cc
+++ b/runtime/runtime.cc
@@ -75,6 +75,7 @@ Runtime::Runtime()
       is_explicit_gc_disabled_(false),
       default_stack_size_(0),
       heap_(NULL),
+      max_spins_before_thin_lock_inflation_(Monitor::kDefaultMaxSpinsBeforeThinLockInflation),
       monitor_list_(NULL),
       thread_list_(NULL),
       intern_table_(NULL),
@@ -350,6 +351,7 @@ Runtime::ParsedOptions* Runtime::ParsedOptions::Create(const Options& options, b
   // Only the main GC thread, no workers.
   parsed->conc_gc_threads_ = 0;
   parsed->stack_size_ = 0;  // 0 means default.
+  parsed->max_spins_before_thin_lock_inflation_ = Monitor::kDefaultMaxSpinsBeforeThinLockInflation;
   parsed->low_memory_mode_ = false;
 
   parsed->is_compiler_ = false;
@@ -510,6 +512,10 @@ Runtime::ParsedOptions* Runtime::ParsedOptions::Create(const Options& options, b
         return NULL;
       }
       parsed->stack_size_ = size;
+    } else if (StartsWith(option, "-XX:MaxSpinsBeforeThinLockInflation=")) {
+      parsed->max_spins_before_thin_lock_inflation_ =
+          strtoul(option.substr(strlen("-XX:MaxSpinsBeforeThinLockInflation=")).c_str(),
+                  nullptr, 10);
     } else if (option == "-XX:LongPauseLogThreshold") {
       parsed->long_pause_log_threshold_ =
           ParseMemoryOption(option.substr(strlen("-XX:LongPauseLogThreshold=")).c_str(), 1024);
@@ -866,6 +872,8 @@ bool Runtime::Init(const Options& raw_options, bool ignore_unrecognized) {
   default_stack_size_ = options->stack_size_;
   stack_trace_file_ = options->stack_trace_file_;
 
+  max_spins_before_thin_lock_inflation_ = options->max_spins_before_thin_lock_inflation_;
+
   monitor_list_ = new MonitorList;
   thread_list_ = new ThreadList;
   intern_table_ = new InternTable;
@@ -901,7 +909,7 @@ bool Runtime::Init(const Options& raw_options, bool ignore_unrecognized) {
   // objects. We can't supply a thread group yet; it will be fixed later. Since we are the main
   // thread, we do not get a java peer.
   Thread* self = Thread::Attach("main", false, NULL, false);
-  CHECK_EQ(self->thin_lock_id_, ThreadList::kMainId);
+  CHECK_EQ(self->thin_lock_thread_id_, ThreadList::kMainThreadId);
   CHECK(self != NULL);
 
   // Set us to runnable so tools using a runtime can allocate and GC by default