# HG changeset patch
# User kbarrett
# Date 1544313177 18000
# Node ID bf2f2560dd5354e87c975b994f7c1fa31910d37d
# Parent  f94276ccc9fc9d6c5b00cf9bafa77d708e9c2e6b
8214315: G1: fatal error: acquiring lock SATB_Q_FL_lock/1 out of order with lock tty_lock/0
Summary: Add new 'tty' lock rank.
Reviewed-by: eosterlund, tschatzl

diff -r f94276ccc9fc -r bf2f2560dd53 src/hotspot/share/runtime/mutex.cpp
--- a/src/hotspot/share/runtime/mutex.cpp	Sat Dec 08 17:41:17 2018 +0100
+++ b/src/hotspot/share/runtime/mutex.cpp	Sat Dec 08 18:52:57 2018 -0500
@@ -1076,9 +1076,9 @@
   Monitor * least = get_least_ranked_lock_besides_this(Self->owned_locks());
   assert(least != this, "Specification of get_least_... call above");
   if (least != NULL && least->rank() <= special) {
-    tty->print("Attempting to wait on monitor %s/%d while holding"
-               " lock %s/%d -- possible deadlock",
-               name(), rank(), least->name(), least->rank());
+    ::tty->print("Attempting to wait on monitor %s/%d while holding"
+                 " lock %s/%d -- possible deadlock",
+                 name(), rank(), least->name(), least->rank());
     assert(false, "Shouldn't block(wait) while holding a lock of rank special");
   }
   #endif // ASSERT
diff -r f94276ccc9fc -r bf2f2560dd53 src/hotspot/share/runtime/mutex.hpp
--- a/src/hotspot/share/runtime/mutex.hpp	Sat Dec 08 17:41:17 2018 +0100
+++ b/src/hotspot/share/runtime/mutex.hpp	Sat Dec 08 18:52:57 2018 -0500
@@ -87,6 +87,8 @@
   // The rank 'access' is similar to 'special' and has the same restrictions on usage.
   // It is reserved for locks that may be required in order to perform memory accesses
   // that require special barriers, e.g. SATB GC barriers, that in turn uses locks.
+  // The rank 'tty' is also similar to 'special' and has the same restrictions.
+  // It is reserved for the tty_lock.
   // Since memory accesses should be able to be performed pretty much anywhere
   // in the code, that requires locks required for performing accesses being
   // inherently a bit more special than even locks of the 'special' rank.
@@ -104,7 +106,8 @@
   enum lock_types {
        event,
        access         = event          +   1,
-       special        = access         +   2,
+       tty            = access         +   2,
+       special        = tty            +   1,
        suspend_resume = special        +   1,
        vmweak         = suspend_resume +   2,
        leaf           = vmweak         +   2,
@@ -236,7 +239,7 @@
 
   #ifndef PRODUCT
     void print_on(outputStream* st) const;
-    void print() const                      { print_on(tty); }
+    void print() const                      { print_on(::tty); }
     DEBUG_ONLY(int    rank() const          { return _rank; })
     bool   allow_vm_block()                 { return _allow_vm_block; }
 
diff -r f94276ccc9fc -r bf2f2560dd53 src/hotspot/share/runtime/mutexLocker.cpp
--- a/src/hotspot/share/runtime/mutexLocker.cpp	Sat Dec 08 17:41:17 2018 +0100
+++ b/src/hotspot/share/runtime/mutexLocker.cpp	Sat Dec 08 18:52:57 2018 -0500
@@ -199,7 +199,7 @@
 
 // Using Padded subclasses to prevent false sharing of these global monitors and mutexes.
 void mutex_init() {
-  def(tty_lock                     , PaddedMutex  , event,       true,  Monitor::_safepoint_check_never);      // allow to lock in VM
+  def(tty_lock                     , PaddedMutex  , tty,         true,  Monitor::_safepoint_check_never);      // allow to lock in VM
 
   def(CGC_lock                     , PaddedMonitor, special,     true,  Monitor::_safepoint_check_never);      // coordinate between fore- and background GC
   def(STS_lock                     , PaddedMonitor, leaf,        true,  Monitor::_safepoint_check_never);