Review request: White box testing API for HotSpot

[Mikael Gerdin]

David,

On 2012-01-13 00:00, David Holmes wrote:
> Hi Mikael,
>
> On 13/01/2012 2:20 AM, Mikael Gerdin wrote:
>>> wbapi.java: normal Java naming style is to use camel-case for class
>>> names. Though as WB is itself an acronym I'd be okay with WBApi. In fact
>>> I'd be happy with anything other than initial lower-case :)
>>
>> Many of our existing tests have lower-case names so I guess I thought
>> that was some sort of convention, it does not really matter to me.
>
> I think those tests must have been written by C programers ;-)
>
>> WBApi it is then.
>
> Thanks.There is a slight typo in that the file is WBapi.java not WBApi.java

Fixed.

I also re-ran JPRT to verify that it still builds on all platforms and 
found that the size of a region in G1 had changed to size_t, so I added 
a cast to jint (region sizes of >2G seems to be unreasonable).

I also tried with Jim Melvin's patch to run OS X and verified that 
"wbapitest" works on OS X as well.

/Mikael

>
> David
> -----
>
>>
>>>
>>> ---
>>>
>>> test/Makefile: does wbapitest need to be added to the phoney list?
>>
>> Yes, fixed.
>>
>> New webrev at:
>> http://cr.openjdk.java.net/~mgerdin/wbapi/webrev.3/
>> Incremental at:
>> http://cr.openjdk.java.net/~mgerdin/wbapi/webrev.2-to-3/webrev/
>>
>> /Mikael
>>
>>>
>>> ---
>>>
>>> Cheers,
>>> David
>>> -----
>>>
>>>
>>> On 11/01/2012 5:27 AM, Mikael Gerdin wrote:
>>>> Hi all
>>>>
>>>> Back from vacations now with an updated version of the webrev based on
>>>> the feedback received in this thread.
>>>> Changes include:
>>>> * removed install target from makefiles
>>>> * renamed flag form EnableWhiteBoxAPI to remove redundant Enable
>>>> * installs wb.jar into jre/lib and made -XX:+WhiteBoxAPI add wb.jar to
>>>> the boot class path from inside the VM.
>>>>
>>>> http://cr.openjdk.java.net/~mgerdin/wbapi/webrev.2/
>>>>
>>>> Thanks
>>>> Mikael Gerdin
>>>>
>>>> On 2011-11-29 17:04, Mikael Gerdin wrote:
>>>>> Hi
>>>>>
>>>>> I've been working on a white box testing API for HotSpot in order to
>>>>> allow for improved precision in vm testing.
>>>>>
>>>>> The basic idea is to open up the possibility for tests written in Java
>>>>> to call native methods which query or poke the vm in some way.
>>>>>
>>>>> The API is accessible by using the class sun/hotspot/WhiteBox which is
>>>>> not intended to be available in public builds.
>>>>> In order to allow the WhiteBox class access to the VM the
>>>>> registerNatives function is linked to JVM_RegisterWhiteBoxMethods.
>>>>> That
>>>>> function then links all the implementation functions using normal JNI
>>>>> RegisterNatives.
>>>>>
>>>>> The API is not meant to be used by end users for any intent or purpose
>>>>> and as such it is both guarded by "-XX:+UnlockDiagnosticVMOptions
>>>>> -XX:+EnableWhiteboxAPI" and the fact that the class files will not be
>>>>> present in an end user build of a JDK.
>>>>> If the VM crashes after this API has been accessed a note will be
>>>>> written in the hs_err file to signal that the API has been used.
>>>>>
>>>>> Webrev:
>>>>> http://cr.openjdk.java.net/~stefank/mgerdin/wbapi.0/webrev/
>>>>> (thanks to stefank for hosting my webrev :)
>>>>>
>>>>> CR:
>>>>> I'll file a CR tomorrow.
>>>>>
>>>>> Change comments:
>>>>>
>>>>> make/jprt.properties
>>>>>
>>>>> Add a test target to make sure that the API is available on all
>>>>> supported platforms
>>>>>
>>>>> make/**
>>>>>
>>>>> Makefile changes to build the class sun/hotspot/WhiteBox, put it in a
>>>>> JAR file and copy it to the jre/lib/endorsed directory in the export
>>>>> targets.
>>>>> The BSD makefile changes are not tested since I don't have access to
>>>>> any
>>>>> BSD/OSX machine to test them on.
>>>>>
>>>>> src/share/vm/prims/nativeLookup.cpp
>>>>>
>>>>> Special-case the method sun/hotspot/WhiteBox/registerNatives and
>>>>> link it
>>>>> to JVM_RegisterWhiteBoxMethods
>>>>>
>>>>> src/share/vm/prims/whitebox.*
>>>>>
>>>>> The implementation of the white box API. The actual API functions are
>>>>> only examples of what we want to be able to do using the API.
>>>>>
>>>>> src/share/vm/runtime/globals.hpp
>>>>>
>>>>> Add the command line flag
>>>>>
>>>>> src/share/vm/utilities/vmError.cpp
>>>>>
>>>>> Print a message in hs_err files when white box API has been used.
>>>>>
>>>>> test/Makefile
>>>>>
>>>>> Add a makefile test target for the white box API test
>>>>>
>>>>> test/sanity/wbapi.java
>>>>>
>>>>> JTreg test to ensure that the API works.
>>>>>
>>>>>
>>>>> Thanks
>>>>> /Mikael Gerdin
>>>>