RFR 8159284: bigapps/Jetty - assert(jfa->last_Java_sp() > sp()) failed with tracing code in use

[Coleen Phillimore]

On 8/2/16 2:22 PM, Coleen Phillimore wrote:
>
> Fred, Thank you for reviewing this.
>
> On 8/2/16 2:02 PM, Frederic Parain wrote:
>> Coleen,
>>
>> src/cpu/aarch64/vm/frame_aarch64.cpp
>>
>>   line 116: return entry_frame_is_safe(thread);
>>   line 207: return sender.is_entry_frame_safe(thread);
>>
>>   Method names are different, is it a typo?
>>
>
> Yes, it is a typo.  Thank you for catching it.
>
>> src/cpu/sparc/vm/frame_sparc.cpp
>>
>>   No comments
>>
>> src/cpu/x86/vm/frame_x86.cpp
>>
>>   No comments
>>
>> src/share/vm/runtime/frame.cpp
>>
>>   No comments
>>
>> src/share/vm/runtime/frame.hpp
>>
>>   I would expect the new method name to be is_entry_frame_safe()
>>   as most tester methods begin with "is_" but I this is just a
>>   personal opinion.
>
> I named it entry_frame_is_safe() because I thought it looked less 
> redundant and more distinct in the code fragments where they occurred:
>
>     // Entry frame checks
>     if (is_entry_frame()) {
>       // an entry frame must have a valid fp.
>
>       if (!fp_safe) return false;
>
>       return entry_frame_is_safe(thread);
>     }
>
> is_entry_frame_safe() looks like is_entry_frame() or implies it's a 
> "safe" call to is_entry_frame.
>
> I guess it is the standard to start with 'is' for these sorts of 
> tests.   How about is_safe_entry_frame() ?

I've got it.  There's is_interpreted_frame and there's 
is_interpreted_frame_valid.  I'll use is_entry_frame_valid for consistency.

Thanks,
Coleen

>
> thanks,
> Coleen
>
>>
>> Fred
>>
>> On 08/01/2016 07:38 PM, Coleen Phillimore wrote:
>>> Summary: Test condition in assert in frame::safe_for_sender() for entry
>>> frames and return false.
>>>
>>> This bug is for a confidential part of the project that needs more
>>> robustness checks to verify that frame::sender() can be called.
>>>
>>> Also refactored into frame::entry_frame_is_safe() because these
>>> platforms had the same code for entry frames to determine whether it is
>>> still safe to trust this frame to call sender(). These platforms had
>>> also the same assert in sender_for_entry_frame() that the sampling code
>>> hit.
>>>
>>> Tested with our nightly tests on all platforms and bigapps/Jetty.
>>>
>>> open webrev at http://cr.openjdk.java.net/~coleenp/8159284.01/webrev
>>>
>>> Thanks,
>>> Coleen
>>>
>