RFR 8222379: JFR TestClassLoadEvent.java failed due to EXCEPTION_ACCESS_VIOLATION

[Calvin Cheung]

On 4/17/19, 11:41 AM, coleen.phillimore at oracle.com wrote:
>
>
> On 4/17/19 12:05 PM, Calvin Cheung wrote:
>> Hi Coleen,
>>
>> Thanks for fixing it and the change looks good.
>>
>> I'm wondering instead of having has_jfr_option(), could the 
>> JfrRecorder::is_enabled() be used instead?
>
> Yes, this would be a lot better, but JfrRecorder::on_vm_init() is 
> called after we map in the CDS regions (I just checked).
Too bad we couldn't use that function.
Your updated comment looks good.

thanks,
Calvin
>
> Coleen
>>
>> The _enable field is set via the JfrRecorder::on_vm_init() and it is 
>> indirectly called during vm init in Threads::create_vm() via 
>> JFR_ONLY(Jfr::on_vm_init();). However, JfrRecorder::is_enabled() is 
>> currently used within only JFR code.
>>
>> thanks,
>> Calvin
>>
>> On 4/17/19, 5:24 AM, coleen.phillimore at oracle.com wrote:
>>> Summary: Give fatal error if CDS loses archive mapping; but map 
>>> Windows RW because remapping is dangerous.
>>>
>>> Ioi and I discussed this change and thought it is best.  Windows 
>>> only maps the CDS archive around 50% time because of ASLR and this 
>>> retains the startup performance improvements for CDS on windows.
>>>
>>> Tested with mach5 tier1-3.
>>>
>>> open webrev at 
>>> http://cr.openjdk.java.net/~coleenp/2019/8222379.01/webrev
>>> bug link https://bugs.openjdk.java.net/browse/JDK-8222379
>>>
>>> Thanks,
>>> Coleen
>>>
>