[kaffe] CVS kaffe (hkraemer): fixed race between gc invocation and thread initialization

[Kaffe CVS]

PatchSet 5699 
Date: 2004/12/21 11:46:51
Author: hkraemer
Branch: HEAD
Tag: (none) 
Log:
fixed race between gc invocation and thread initialization

Members: 
	ChangeLog:1.3244->1.3245 
	kaffe/kaffevm/threadData.h:1.4->1.5 
	kaffe/kaffevm/kaffe-gc/gc-refs.c:1.7->1.8 

Index: kaffe/ChangeLog
diff -u kaffe/ChangeLog:1.3244 kaffe/ChangeLog:1.3245
--- kaffe/ChangeLog:1.3244	Tue Dec 21 08:47:08 2004
+++ kaffe/ChangeLog	Tue Dec 21 11:46:51 2004
@@ -1,3 +1,12 @@
+2004-12-21  Helmer Kraemer  <hkraemer at freenet.de>
+
+	* kaffe/kaffevm/threadData.h (THREAD_DATA_INITIALIZED): new macro
+
+	* kaffe/kaffevm/kaffe-gc/gc-refs.c (liveThreadWalker): properly handle
+	partially initialized threads
+
+	Reported by: Alexander Boettcher <ab764283 at os.inf.tu-dresden.de>
+	
 2004-12-21  Adam Heath  <doogie at brainfood.com>
 
 	* AUTHORS:
Index: kaffe/kaffe/kaffevm/threadData.h
diff -u kaffe/kaffe/kaffevm/threadData.h:1.4 kaffe/kaffe/kaffevm/threadData.h:1.5
--- kaffe/kaffe/kaffevm/threadData.h:1.4	Wed Jul  7 16:05:13 2004
+++ kaffe/kaffe/kaffevm/threadData.h	Tue Dec 21 11:46:54 2004
@@ -38,4 +38,6 @@
 	int		needOnStack;
 } threadData;
 
+#define THREAD_DATA_INITIALIZED(td) ((td)->jniEnv != NULL)
+
 #endif
Index: kaffe/kaffe/kaffevm/kaffe-gc/gc-refs.c
diff -u kaffe/kaffe/kaffevm/kaffe-gc/gc-refs.c:1.7 kaffe/kaffe/kaffevm/kaffe-gc/gc-refs.c:1.8
--- kaffe/kaffe/kaffevm/kaffe-gc/gc-refs.c:1.7	Sun Dec 19 06:41:29 2004
+++ kaffe/kaffe/kaffevm/kaffe-gc/gc-refs.c	Tue Dec 21 11:46:54 2004
@@ -154,14 +154,22 @@
 {
   Collector *c = (Collector *)private;
   threadData *thread_data = KTHREAD(get_data)(tid);
-  Hjava_lang_VMThread *thread = (Hjava_lang_VMThread *)thread_data->jlThread;
 
-  KGC_markObject(c, NULL, unhand(thread)->thread);
-  KGC_markObject(c, NULL, thread);
-  
-  if (thread_data->exceptObj != NULL)
+  /* if the gc is invoked while a new thread is being
+   * initialized, we should not make any assumptions
+   * about what is stored in its thread_data 
+   */
+  if (THREAD_DATA_INITIALIZED(thread_data))
     {
-      KGC_markObject(c, NULL, thread_data->exceptObj);
+      Hjava_lang_VMThread *thread = (Hjava_lang_VMThread *)thread_data->jlThread;
+
+      KGC_markObject(c, NULL, unhand(thread)->thread);
+      KGC_markObject(c, NULL, thread);
+  
+      if (thread_data->exceptObj != NULL)
+        {
+          KGC_markObject(c, NULL, thread_data->exceptObj);
+        }
     }
 
   TwalkThread(c, tid);