Correctly claim and release the c ext mutex when required.

PullRequest: truffleruby/743

Author: aardvark179

lib/truffle/truffle/cext.rb

@@ -1592,6 +1592,10 @@ def rb_thread_create(fn, args)
     end
   end
 
+  def rb_thread_call_with_gvl(function, data)
+    Truffle.invoke_primitive(:interop_call_c_with_mutex, function, [data])
+  end
+
   def rb_thread_call_without_gvl(function, data1, unblock, data2)
     if unblock
       unblocker = -> {

src/main/c/cext/ruby.c

@@ -2526,7 +2526,7 @@ void rb_gc(void) {
 // Threads
 
 void *rb_thread_call_with_gvl(gvl_call function, void *data1) {
-  return function(data1);
+  return polyglot_invoke(RUBY_CEXT, "rb_thread_call_with_gvl", function, data1);
 }
 
 void *rb_thread_call_without_gvl(gvl_call function, void *data1, rb_unblock_function_t *unblock_function, void *data2) {

src/main/java/org/truffleruby/cext/CExtNodes.java

@@ -121,17 +121,23 @@ public abstract static class CallCWithMutexNode extends PrimitiveArrayArgumentsN
         public Object callCWithMutex(TruffleObject receiver, DynamicObject argsArray,
                 @Cached("create()") ArrayToObjectArrayNode arrayToObjectArrayNode,
                 @Cached("EXECUTE.createNode()") Node executeNode,
-                @Cached("create()") BranchProfile exceptionProfile) {
+                @Cached("create()") BranchProfile exceptionProfile,
+                @Cached("createBinaryProfile()") ConditionProfile ownedProfile) {
             final Object[] args = arrayToObjectArrayNode.executeToObjectArray(argsArray);
 
             if (getContext().getOptions().CEXT_LOCK) {
                 final ReentrantLock lock = getContext().getCExtensionsLock();
+                boolean owned = lock.isHeldByCurrentThread();
 
-                MutexOperations.lockInternal(getContext(), lock, this);
-                try {
+                if (ownedProfile.profile(!owned)) {
+                    MutexOperations.lockInternal(getContext(), lock, this);
+                    try {
+                        return execute(receiver, args, executeNode, exceptionProfile);
+                    } finally {
+                        MutexOperations.unlockInternal(lock);
+                    }
+                } else {
                     return execute(receiver, args, executeNode, exceptionProfile);
-                } finally {
-                    MutexOperations.unlockInternal(lock);
                 }
             } else {
                 return execute(receiver, args, executeNode, exceptionProfile);
@@ -158,17 +164,23 @@ public abstract static class CallCWithoutMutexNode extends PrimitiveArrayArgumen
         public Object callCWithoutMutex(TruffleObject receiver, DynamicObject argsArray,
                 @Cached("create()") ArrayToObjectArrayNode arrayToObjectArrayNode,
                 @Cached("EXECUTE.createNode()") Node executeNode,
-                @Cached("create()") BranchProfile exceptionProfile) {
+                @Cached("create()") BranchProfile exceptionProfile,
+                @Cached("createBinaryProfile()") ConditionProfile ownedProfile) {
             final Object[] args = arrayToObjectArrayNode.executeToObjectArray(argsArray);
 
             if (getContext().getOptions().CEXT_LOCK) {
                 final ReentrantLock lock = getContext().getCExtensionsLock();
+                boolean owned = lock.isHeldByCurrentThread();
 
-                MutexOperations.unlockInternal(lock);
-                try {
+                if (ownedProfile.profile(owned)) {
+                    MutexOperations.unlockInternal(lock);
+                    try {
+                        return execute(receiver, args, executeNode, exceptionProfile);
+                    } finally {
+                        MutexOperations.lockInternal(getContext(), lock, this);
+                    }
+                } else {
                     return execute(receiver, args, executeNode, exceptionProfile);
-                } finally {
-                    MutexOperations.lockInternal(getContext(), lock, this);
                 }
             } else {
                 return execute(receiver, args, executeNode, exceptionProfile);