[prev in list] [next in list] [prev in thread] [next in thread] 

List:       openjdk-serviceability-dev
Subject:    Re: RFR: 8305913: com/sun/jdi/JdbLastErrorTest.java failed with "'lastError = 42' missing from stdou
From:       Kevin Walls <kevinw () openjdk ! org>
Date:       2023-04-27 10:11:22
Message-ID: vf2pJ3Ba2hW4hfy-MTbprv7Zg7xE5qKe49KuFRYmtmE=.019be59a-8016-471a-b417-6e845c497585 () github ! com
[Download RAW message or body]

On Sat, 15 Apr 2023 10:15:20 GMT, Kevin Walls <kevinw@openjdk.org> wrote:

> > This test is failing often since 8304725 added a call to \
> > Thread::current_in_asgct().  This can end up being called e.g. when resolving \
> > calls, and then the OS last error value is lost. 
> > The test is reliable with a single warm-up call to getLastError.invoke() before \
> > the loop. 
> > The test was introduced when in JDK-8292302 a change was undone that had made \
> > JavaThread::threadObj call Thread::current_or_null_safe, as the use of TLS upset \
> > this case of accessing last error directly. 
> > This new Thread::current_in_asgct() case shows that the VM will find new ways to \
> > interfere with the last error value, or at least new VM code keeps wanting to \
> > call Thread::current.  This testcase is kind of niche usage, so it not an \
> > argument that VM code should not be calling Thread::current.   If this test is to \
> > stay active, it needs to have this warm-up getLastError call.  (If there are more \
> > issues, it might mean removing the test.)
> 
> Kevin Walls has updated the pull request incrementally with one additional commit \
> since the last revision: 
> comment update feedback

Thanks for looking at this, and for the Panama pointer to JDK-8294970 - I'm checking \
if that completely solves it for this testcase...

-------------

PR Comment: https://git.openjdk.org/jdk/pull/13481#issuecomment-1525338902


[prev in list] [next in list] [prev in thread] [next in thread]