RFR(XS): [TEST] add test to verify EnableTrace works

[Liu, Xin]

Hi, David, 
Could you review this new revision?
Webrev: http://cr.openjdk.java.net/~phh/8209863/webrev.02/
bug: https://bugs.openjdk.java.net/browse/JDK-8209863

I should verify new tests using both Openjdk/Oraclejdk. Thank you for heading up. 

Thanks,
--lx

On 9/4/18, 11:05 PM, "Liu Xin" <navy.xliu at gmail.com> wrote:

    Hi, David, 
    
    Thanks to investigate the closed implementation.
    
    Indeed, OracleJDK shows “JAVA(TM)” instead of OpenJDK. 
    
    $java -XX:+EnableTracing -version
    java version "1.8.0_171"
    Java(TM) SE Runtime Environment (build 1.8.0_171-b11)
    Java HotSpot(TM) 64-Bit Server VM (build 25.171-b11, mixed mode)
    
    I will add a guard for the Test.  Furthermore, I think I need to check if it exits with 0 for OracleJDK. 
    The right behavior of OracleJDK8 is to accept this flag yet suppress all events. 
    
    Thanks,
    —lx
    
    
    > On Sep 4, 2018, at 9:51 PM, David Holmes <david.holmes at oracle.com> wrote:
    > 
    > Hi Liu Xin,
    > 
    > On 4/09/2018 7:45 PM, David Holmes wrote:
    >> On 4/09/2018 10:12 AM, Liu, Xin wrote:
    >>> Hi, David,
    >>> Thank you for reviewing it.
    >>> 
    >>> If you are using OracleJDK, it won't have any output. OracleJDK doesn't suffer from crash. I guess It suppress events unconditionally.
    >>> For JDK8u, "-XX:+EnableTracing -version" will dump some events.  It won't crash if it has this patch http://hg.openjdk.java.net/jdk8u/jdk8u-dev/hotspot/rev/80ee2541504e
    >>> The attachment is the output.
    >> If the Oracle JDK doesn't produce any output then this test will fail on the Oracle JDK so can't be accepted in current form.
    >> There's something going on with EnableTracing that I'm not understanding. I'll try to take a closer look tomorrow ( was on a day off today).
    > 
    > Okay ... the Oracle JDK replaces the OpenJDK tracing facility with JFR which completely ignores the EnableTracing flag.
    > 
    > If the test is simply verifying that -XX:+EnableTracing doesn't crash then it can reduce to just:
    > 
    > /*
    > * @test
    > * @summary Ensure -XX:+EnableTracing doesn't crash
    > * @run main/othervm -XX:+EnableTracing TestEnableTracing
    > */
    > public class TestEnableTracing {
    >    public static void main(String[] args) {
    >    }
    > }
    > 
    > If you want to actually verify some of the trace output then you will need to guard the shouldMatch/Contain statements with something like:
    > 
    > if (output.getOutput().contains("OpenJDK")) {
    > ...
    > }
    > 
    > I don't think there is a direct way to ensure the test is only executed on an OpenJDK binary.
    > 
    > Thanks,
    > David
    > 
    >> Thanks,
    >> David
    >>> 
    >>> Output of jtreg
    >>> ###
    >>> # Running suite single for openJDK
    >>> # Results are available in build/brazil-open-single-tests
    >>> ###
    >>> Directory "build/JTwork" not found: creating
    >>> Passed: runtime/EnableTracing/TestEnableTracing.java
    >>> Test results: passed: 1
    >>> Report written to /local/home/xxinliu/ws-openjdk8/build/OpenJDK8CompatibilityTests/OpenJDK8CompatibilityTests-1.0/RHEL5_64/DEV.STD.PTHREAD/build/brazil-open-single-tests/html/report.html 
    >>> Results written to /local/home/xxinliu/ws-openjdk8/build/OpenJDK8CompatibilityTests/OpenJDK8CompatibilityTests-1.0/RHEL5_64/DEV.STD.PTHREAD/build/JTwork 
    >>> 
    >>> Thanks,
    >>> --lx
    >>> 
    >>> 
    >>> On 9/2/18, 10:01 PM, "David Holmes" <david.holmes at oracle.com> wrote:
    >>> 
    >>>      Hi,
    >>>      On 25/08/2018 2:35 AM, Liu, Xin wrote:
    >>>      > Hi, hotspot-Runtime Developers,
    >>>      >
    >>>      > Could you review this small tests?
    >>>      > It adds a new test to verify +EnableTracing works for jdk8u.
    >>>      I don't see any output produced with just "-XX:+EnableTracing -version". ??
    >>>        >
    >>>     /java/re/jdk/8u172/promoted/latest/binaries/linux-amd64/fastdebug/bin/java 
    >>>      -XX:+EnableTracing -version
    >>>      java version "1.8.0_172-fastdebug"
    >>>      Java(TM) SE Runtime Environment (build 1.8.0_172-fastdebug-b35)
    >>>      Java HotSpot(TM) 64-Bit Server VM (build 25.172-b35-fastdebug, mixed mode)
    >>>      Thanks,
    >>>      David
    >>>      > BUG:  https://bugs.openjdk.java.net/browse/JDK-8209863
    >>>      > WEBREV: http://cr.openjdk.java.net/~phh/8209863/webrev.00/
    >>>      >
    >>>      > Thanks,
    >>>      > -lx
    >>>      >
    >>>