RFR(XS): 8204135: jtreg: Fix failing RTM test TestUseRTMXendForLockBusy

[Gustavo Romero]

Thanks! :)

On 06/20/2018 05:08 PM, Lindenmaier, Goetz wrote:
> Done ��
> 
> Best regards,
>    Goetz.
> 
>> -----Original Message-----
>> From: Gustavo Romero <gromero at linux.vnet.ibm.com>
>> Sent: Wednesday, June 20, 2018 9:40 PM
>> To: Lindenmaier, Goetz <goetz.lindenmaier at sap.com>
>> Cc: Igor Ignatyev <igor.ignatyev at oracle.com>; hotspot-compiler-
>> dev at openjdk.java.net; Doerr, Martin <martin.doerr at sap.com>
>> Subject: Re: RFR(XS): 8204135: jtreg: Fix failing RTM test
>> TestUseRTMXendForLockBusy
>>
>> Hi Igor,
>>
>> On 06/20/2018 03:23 PM, Igor Ignatyev wrote:
>>> as your patch has been reviewed by two reviewers, it is fine to be pushed.
>>
>> Thanks for reviewing it.
>>
>> Goetz, could you please sponsor the change?
>>
>>
>> Regards,
>> Gustavo
>>
>>> -- Igor
>>>
>>>> On Jun 20, 2018, at 5:17 AM, Gustavo Romero
>> <gromero at linux.vnet.ibm.com> wrote:
>>>>
>>>> Hi Igor,
>>>>
>>>> On 06/15/2018 10:12 AM, Lindenmaier, Goetz wrote:
>>>>> I had a look at your fix. As I understand the test it's just
>>>>> what was intended to do. Also, it fixed the test in our runs.
>>>>> Reviewed.
>>>>> I would volunteer to sponsor this.
>>>>
>>>> Goetz reviewed the change. Is it OK to be pushed?
>>>>
>>>>
>>>> Thanks.
>>>>
>>>> Best regards,
>>>> Gustavo
>>>>
>>>>> Best regards,
>>>>>     Goetz.
>>>>>> -----Original Message-----
>>>>>> From: Gustavo Romero [mailto:gromero at linux.vnet.ibm.com]
>>>>>> Sent: Donnerstag, 31. Mai 2018 04:05
>>>>>> To: hotspot-compiler-dev at openjdk.java.net;
>> igor.ignatyev at oracle.com
>>>>>> Cc: Lindenmaier, Goetz <goetz.lindenmaier at sap.com>; Doerr, Martin
>>>>>> <martin.doerr at sap.com>
>>>>>> Subject: RFR(XS): 8204135: jtreg: Fix failing RTM test
>>>>>> TestUseRTMXendForLockBusy
>>>>>>
>>>>>> Hi,
>>>>>>
>>>>>> Could the following change be reviewed please?
>>>>>>
>>>>>> webrev: http://cr.openjdk.java.net/~gromero/8204135/v1
>>>>>> bug   : https://bugs.openjdk.java.net/browse/JDK-8204135
>>>>>>
>>>>>> It fixes currently failing RTM test "TestUseRTMXendForLockBusy" by
>>>>>> changing
>>>>>> in which cases UseRTMForStackLocks flags must be enabled/disabled.
>>>>>>
>>>>>> I could not track down on the timeline when exactly that test stopped
>> to
>>>>>> pass, however my understanding is that if inflateMonitor is 'false' that
>>>>>> should /not/ imply that UseRTMForStackLocks is also 'false'. Thus I
>>>>>> understand that for this particular test if inflated monitors are used,
>>>>>> then UseRTMForStackLocks has to be disabled, i.e. 'false'. On the other
>>>>>> hand, if inflated monitors are /not/ used, then UseRTMForStackLocks
>> must
>>>>>> be
>>>>>> enabled.
>>>>>>
>>>>>> Currently the test is failing for the following cases where inflateMonitor
>>>>>> is 'false', because it implies that UseRTMForStackLocks is disabled and
>> so
>>>>>> no abort statistics is generated (which is correct from the JVM's
>>>>>> perspective):
>>>>>>
>>>>>>            // stack lock, xabort on lock busy
>>>>>>            verifyXendForLockBusy(false, false);
>>>>>>            // stack lock, xend on lock busy
>>>>>>            verifyXendForLockBusy(false, true);
>>>>>>
>>>>>> In other words, "stack lock" case should imply UseRTMForStackLocks =
>> 'true',
>>>>>> not 'false'.
>>>>>>
>>>>>> Cases:
>>>>>>            // inflated lock, xabort on lock busy
>>>>>>            verifyXendForLockBusy(true, false);
>>>>>>            // inflated lock, xend on lock busy
>>>>>>            verifyXendForLockBusy(true, true);
>>>>>>
>>>>>> are not failing because UseRTMForStackLocks = 'true' and they will
>> generate
>>>>>> proper abort statistics when  +UseRTMXendForLockBusy ('xend' is used
>> to
>>>>>> finish the transaction) or when -UseRTMXendForLockBusy ('xabort' is
>> used
>>>>>> to finish the transaction).
>>>>>>
>>>>>> So, in summing up: (a) inflated lock cases are not being tested correctly
>>>>>> (since UseRTMForStackLocks is always enabled) and (b) stack lock cases
>> are
>>>>>> failing because UseRTMForStackLocks is always disabled.
>>>>>>
>>>>>> @Igor, it's a long time ago, but maybe you recall some details on that
>>>>>> test... :-)
>>>>>>
>>>>>>
>>>>>> Thank you.
>>>>>>
>>>>>> Best regards,
>>>>>> Gustavo
>>>>
>>>
>