8221730: jcmd process name matching broken

[David Holmes]

Hi Daniil,

On 5/04/2019 12:01 pm, Daniil Titov wrote:
> Hi David,
> 
> I didn't use "hg rename".  Now I recreated the patch using "hg rename" for moving test/hotspot/jtreg/serviceability/dcmd/framework/TestJavaProcess.java to test/hotspot/jtreg/serviceability/dcmd/framework/process/TestJavaProcess.java. I also used the latest version of webrev.ksh (25.17) to re-create a webrev (I uploaded it as webrev.03).  However, I still don't see that renaming is somehow reflected in the webrev. Not sure what might be wrong here. The hg version is 4.5.3, the OS is Ubuntu 18.04.2 LTS.

Strange. Here's an example of where the rename shows up in the webrev:

http://cr.openjdk.java.net/~dholmes/8213233/webrev/

Anyway as long as it was done with hg rename that is fine.

Thanks,
David
----

> 
> Webrev: http://cr.openjdk.java.net/~dtitov/8221730/webrev.03/
> Bug: https://bugs.openjdk.java.net/browse/JDK-8221730
> 
> Thanks!
> 
> Best regards,
> Daniil
> 
> On 4/4/19, 5:45 PM, "David Holmes" <david.holmes at oracle.com> wrote:
> 
>      Hi Daniil,
>      
>      On 5/04/2019 8:17 am, Daniil Titov wrote:
>      > Hi David and JC,
>      >
>      > Thank you for reviewing this change. Please review a new version of
>      > the fix that adds additional tests as David suggested. The tests are
>      > added to
>      > test/hotspot/jtreg/serviceability/dcmd/framework/VMVersionTest.java and
>      > test the cases when Java process is started with -jar or -m (--module)
>      > options.
>      
>      Looks good - thanks for doing that.
>      
>      > Since unnamed packages are not allowed in the modules, file
>      > test/hotspot/jtreg/serviceability/dcmd/framework/TestJavaProcess.java
>      > was moved to
>      > test/hotspot/jtreg/serviceability/dcmd/framework/process/TestJavaProcess.java.
>      
>      Did you use "hg rename" for that? The webrev doesn't show that you did.
>      
>      Thanks,
>      David
>      
>      >
>      > Webrev: http://cr.openjdk.java.net/~dtitov/8221730/webrev.02/
>      > Bug: https://bugs.openjdk.java.net/browse/JDK-8221730
>      >
>      > Thanks!
>      > --Daniil
>      >
>      >
>      > On 4/3/19, 5:23 PM, "David Holmes" <david.holmes at oracle.com> wrote:
>      >
>      >      Hi Daniil,
>      >
>      >      This seems reasonable, but can we add a suitable regression test please
>      >      to verify behaviour before JDK-8205654 and with this fix.
>      >
>      >      Thanks,
>      >      David
>      >
>      >      On 4/04/2019 5:02 am, Daniil Titov wrote:
>      >      > Please review the change that makes jcmd process name matching on Linux platform consistent with pre-existing behavior.
>      >      >
>      >      > On other platforms (and on Linux platform before changes [3]) the jcmd uses system property "sun.rt.javaCommand"  (see sun.jvmstat.monitor. MonitoredVmUtil.mainClass(MonitoredVm, boolean) that is called from sun.tools.common. ProcessArgumentMatcher at line 96) and treats the part before the first space as a main class when matching the process name. However, if the application  is started with -jar option this part contains the path to the jar file. If  -m or --module option is used this part contains the module name and the main class (if the main class was specified in the command line) in the format <modulename>/<mainclass>.  After changes [3] , on Linux platform the proc filesystem is used to find a Java process, however, it always matches the process name against the main class regardless what options were used to launch the application. This created discrepancies between old and new behavior on Linux platform as well as between behavior on Linux and other platforms. Th!
>      >      >   e fix changes sun.tool.ProcessHelper (that was introduced in [3]) to correct these discrepancies.
>      >      >
>      >      >
>      >      > Reference:
>      >      > [1]  Webrev: http://cr.openjdk.java.net/~dtitov/8221730/webrev.01
>      >      > [2] Bug: https://bugs.openjdk.java.net/browse/JDK-8221730
>      >      > [3] https://bugs.openjdk.java.net/browse/JDK-8205654
>      >      >
>      >      >
>      >      > Thanks!
>      >      > --Daniil
>      >      >
>      >      >
>      >
>      >
>      >
>      
> 
>