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

[Lindenmaier, Goetz]

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
> >>
> >