# HG changeset patch
# User xlu
# Date 1231877323 28800
# Node ID 4db4e58c16bd5a55fcbd4be1eabf368c05537b67
# Parent  a0401dc51d0b4fe9a92e76810936a41d2387ef9e
6791815: Fix for 6471657 can cause deadlock on non-Solaris platforms when initializing direct buffer support
Summary: Place the state transition inside the loop so that the VMThread could proceed for safepoint
Reviewed-by: dholmes, never, acorn

diff -r a0401dc51d0b -r 4db4e58c16bd src/share/vm/prims/jni.cpp
--- a/src/share/vm/prims/jni.cpp	Thu Jan 08 16:27:28 2009 -0500
+++ b/src/share/vm/prims/jni.cpp	Tue Jan 13 12:08:43 2009 -0800
@@ -2691,8 +2691,13 @@
 
     directBufferSupportInitializeEnded = 1;
   } else {
-    ThreadInVMfromNative tivn(thread); // set state as yield_all can call os:sleep
     while (!directBufferSupportInitializeEnded && !directBufferSupportInitializeFailed) {
+      // Set state as yield_all can call os:sleep. On Solaris, yield_all calls
+      // os::sleep which requires the VM state transition. On other platforms, it
+      // is not necessary. The following call to change the VM state is purposely
+      // put inside the loop to avoid potential deadlock when multiple threads
+      // try to call this method. See 6791815 for more details.
+      ThreadInVMfromNative tivn(thread);
       os::yield_all();
     }
   }