[10] RFR(M) 8182701: Modify JVMCI to allow Graal Compiler to expose platform MBean

[Mandy Chung]

> On Jul 25, 2017, at 1:33 AM, Doug Simon <doug.simon at oracle.com> wrote:
> 
> 
>> On 25 Jul 2017, at 01:37, Mandy Chung <mandy.chung at oracle.com> wrote:
>> 
>> Vladimir,
>> 
>> I believe you don’t want to add the dependency from JVMCI to java.management.  Otherwise, JVMCI can’t run with only java.base.
> 
> The dependency is unfortunate. Can you suggest how JVMCI platform beans could participate in platform bean registration without the dependency?
> 

If it exposes a MBean, the dependency would be needed.

One consideration might be to separate the JVMCI MBean provider in its own module so that it’s registered only when such module is resolved in the module graph.  This way JVMCI can work even if java.management is not present.

>> Is the MBean in jdk.internal.vm.compiler or in Lab’s Graal compiler?
> 
> Anything in Lab’s Graal compiler is destined for JDK Graal so the distinction is only temporary at best.
> 

Good to know.

>> 
>> src/jdk.internal.vm.ci/share/classes/jdk/vm/ci/services/src/jdk/vm/ci/services/internal/JVMCIMXBeans.java
>> - I suspect this file meant to be in src/jdk.internal.vm.ci/share/classes/src/jdk.internal.vm.ci/share/classes/jdk/vm/ci/services/internal/JVMCIMXBeans.java
> 
> Not sure I follow - there is currently no such directory src/jdk.internal.vm.ci/share/classes/src

Typo - it’s an existing directory:

src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.services/src/jdk/vm/ci/services/internal

Mandy

> 
> -Doug
> 
>>> On Jul 12, 2017, at 2:20 PM, Vladimir Kozlov <vladimir.kozlov at oracle.com> wrote:
>>> 
>>> https://bugs.openjdk.java.net/browse/JDK-8182701
>>> webrev:
>>> http://cr.openjdk.java.net/~kvn/8182701/webrev.jdk/
>>> http://cr.openjdk.java.net/~kvn/8182701/webrev.hs/
>>> 
>>> Contributed by Jaroslav Tulach.
>>> 
>>> JDK itself contains quite a lot of platform MBeans which get registered "on demand". Graal compiler (jdk.internal.vm.compiler) provides its own MBean(s) - however currently there is no way to register it "on demand". JDK9 already contains support for collecting platform MBeans from various modules. We just need to expose Graal MBean through JVMCI.
>>> 
>>> Thanks,
>>> Vladimir
>> 
>