RFR[10] 8190984 : tools/launcher/TestXcheckJNIWarnings.java WARNING was found in the output (original) (raw)

David Holmes david.holmes at oracle.com
Wed Dec 13 00:48:40 UTC 2017

On 13/12/2017 10:41 AM, Brent Christian wrote:

What David said. :)

One other wrinkle: I ProblemList-ed the test a few days ago[1] in

I forgot about that :(

jdk/jdk.  AFAICT, that change is not yet in jdk/hs, so the changes David's pushing can't be used to take the test back off of the ProblemList.  I figure I'll have to file a new issue, to be fixed in jdk/jdk (unless someone has a better idea).

I will see if we can re-sync to hs before I push the changes. Otherwise I could switch everything to jdk/jdk. Otherwise a new issue will need to be filed.

Thanks, David

Thanks, -Brent

1. http://hg.openjdk.java.net/jdk/jdk/rev/b9a19d1e61f2 On 12/12/17 4:18 PM, David Holmes wrote:

IIRC Brent instrumented the localref methods to see how many were being created, and the "50" gives us sufficient capacity. The actual number of local refs introduced seems to be platform and locale specific. Note this only affects the warnings that -Xcheck:jni produces (at least on hotspot). If more properties are added that take us beyond the new capacity then we'll see test failures again and can increase it further. Thanks, David

Mandy

On 12/12/17 4:00 PM, David Holmes wrote: Reviewed! :)

Thanks Brent! I guess I can push these both now. David On 13/12/2017 9:38 AM, Brent Christian wrote: Hi,

Please review this small change to the System.initProperties() native method. The tools/launcher/TestXcheckJNIWarnings.java has begun to fail due to this warning being issued: WARNING: JNI local refs: 41, exceeds capacity: 40 at java.lang.System.initProperties(java.base/Native Method) at java.lang.System.initPhase1(java.base/System.java:1943) This has only been seen on solaris-sparc with LANG=C.  In fact, the warning can also be seen with a simple HelloWorld program, run with -Xcheck:jni.  This started happening as of JDK-8043224 ("-Xcheck:jni improvements to exception checking and excessive local refs"). The following change should be made to prevent the warning: diff -r ed1bb7743b3e src/java.base/share/native/libjava/System.c --- a/src/java.base/share/native/libjava/System.c    Tue Dec 12 19:05:02 2017 +0100 +++ b/src/java.base/share/native/libjava/System.c    Tue Dec 12 15:21:03 2017 -0800 @@ -186,6 +186,9 @@ jobject ret = NULL; jstring jVMVal = NULL; +    if ((*env)->EnsureLocalCapacity(env, 50) < 0) { +        return NULL; +    } sprops = GetJavaProperties(env); CHECKNULLRETURN(sprops, NULL);

Of note: an additional change is needed, to EnsureLocalCapacity itself: 8193222 : EnsureLocalCapacity() should maintain capacity requests through multiple calls That fix has already been proposed and reviewed. These two fixes should be pushed together via hs, which David has kindly offered to do, pending code review approval of my change here. Thanks, -Brent

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