Hi Serguei,
Fair enough, at least this removes a bit of the chance of flakiness :-)
Should we at least clean up the comment for methods that are changed?
/**
* Testcase: check tested threads
* - invoke getFrameCount() for each thread
* - check if frameCount is not less than minimal stack depth
* - invoke getStackTrace() for each thread
* - check if stack depth is not less than frameCount
* - for suspended thread check if stack depth is equal to frameCount
*
* Returns NSK_TRUE if test may continue; or NSK_FALSE for test break.
*/
static int checkThreads(int suspended, const char* kind) {
The " * - check if stack depth is not less than frameCount" is no
longer done with this webrev.
Thanks,
Jc
On Sun, Aug 26, 2018 at 9:52 PM serguei.spit...@oracle.com <
serguei.spit...@oracle.com> wrote:
> Hi Jc,
>
> Initially, I has the same concern.
> But now I think there is no point to take these values on non-suspended
> threads.
> It has to be good enough to compare the values taken on suspended threads
> only.
>
> Thanks,
> Serguei
>
>
> On 8/24/18 16:49, JC Beyler wrote:
>
> Hi Daniil,
>
> Just my two cents about this :)
>
> I was looking at this and wondered if it made sense to fix the test this
> way (I always worry about simplifying a test and losing coverage). I
> understand the bug is that it is possible that between both calls, Graal
> could add some frames and therefore might trip this test:
>
> - if (frameStackSize < frameCount) {
>
> However, by removing the test altogether and only relying on the suspended
> frames, are we not reducing our coverage of the test (basically never
> really testing the running threads anymore, only the suspended ones?).
>
> Alternatively, when we look at this code and the hypothesis of Graal
> stacks "slipping in between calls", two cases could occur:
> A) The Graal frames are present in the first call but not the second
> B) The Graal frames are present in the second call but not the first
>
> In the (B) case, the test would not trip, as frameStackSize would be >=
> frameCount so that is not an issue.
> In the (A) case, we could simply recall the frameCount and assure
> ourselves the frames have disappeared, no?
>
> Something like:
>
> if (frameStackSize < frameCount) {
> // This can occur for Graal if graal frames crept in. Call
> getFrameCount again and see if they have disappeared since
> // frameStackSize seems to say so.
> ... insert call here and a new check...
>
> NSK_COMPLAIN5("Too small stack of %s thread #%d (%s):\n"
> "# getStackTrace(): %d\n"
> "# getFrameCount(): %d\n",
> kind, i, threadsDesc[i].threadName,
> (int)frameStackSize, (int)frameCount);
> nsk_jvmti_setFailStatus();
> }
>
> Just my 2 cents because I worry about simplifying a test for Graal but
> losing coverage in the general case,
> Jc
>
>
>
> On Thu, Aug 23, 2018 at 8:29 PM Daniil Titov <daniil.x.ti...@oracle.com>
> wrote:
>
>> Please review the change that fixes 4 JVMTI tests when running with Graal.
>>
>> One of the checks these tests perform compares the number of frames in
>> the thread's stack returned by JVMTI GetFrameCount() with the number of
>> frames entries returned by JVMTI GetStackTrace(). The thread to be tested
>> executes arithmetic operations in the loop so the consequent calls of
>> GetFrameCount() or/and GetStackTrace() should return the stack trace of
>> the same depth.
>>
>> However, with Graal on, additional "adjustCompilationLevel" frames could
>> appear on the stack trace, e.g.:
>>
>> adjustCompilationLevel:166, HotSpotGraalCompilerFactory
>> (org.graalvm.compiler.hotspot)
>> adjustCompilationLevel:504, HotSpotJVMCIRuntime (jdk.vm.ci.hotspot)
>> testedMethod:56, Test$Runner
>> run:67, Test$Runner
>>
>> that results in the stack depth reported by the first invocation of
>> GetFrameCount() or GetStackTrace() might differ from the stack depth
>> reported by the consequent calls of the same methods.
>>
>> The fix modifies the tests to ensure the check that GetFrameCount () and
>> GetStackTrace() report the same stack depth is performed only if the thread
>> is suspended. For two tests
>> (vmTestbase/nsk/jvmti/scenarios/sampling/SP02/sp02t001/TestDescription.java
>> and
>> vmTestbase/nsk/jvmti/scenarios/sampling/SP06/sp06t001/TestDescription.java)
>> such check for suspended threads already exists so in these tests the
>> problematic check was not modified by just removed.
>>
>> Issue: https://bugs.openjdk.java.net/browse/JDK-8209585
>> Webrev: http://cr.openjdk.java.net/~dtitov/8209585/webrev.01
>>
>> Thanks,
>> Daniil
>>
>>
>>
>
> --
>
> Thanks,
> Jc
>
>
>
--
Thanks,
Jc
