Re: RFR(S): 8247533: SA stack walking sometimes fails with sun.jvm.hotspot.debugger.DebuggerException: get_thread_regs failed for a lwp

[serguei.spit...@oracle.com]

Hi Chris,

I do not see any problems with this change.

Thanks,
Serguei


On 6/25/20 13:29, Chris Plummer wrote:

Ping. I still need one more review for this. There was one updated webev. I list it below so you don't need to dig it up in the long email thread:

I've  updated with webrev based on the new finding that a JavaThread cannot be on the ThreadList after its OS thread has been destroyed since the JavaThread removes itself from the ThreadList, and therefore must be running on its OS thread. The logic of the fix is unchanged from the first webrev, but I updated the comments to better reflect what is going on. I also updated the CR:

https://bugs.openjdk.java.net/browse/JDK-8247533
http://cr.openjdk.java.net/~cjplummer/8247533/webrev.01/index.html

thanks,

Chris

On 6/17/20 1:34 PM, Chris Plummer wrote:

Hello,

Please help review the following:

https://bugs.openjdk.java.net/browse/JDK-8247533
http://cr.openjdk.java.net/~cjplummer/8247533/webrev.00/index.html

The CR contains all the needed details. Here's a summary of changes in each file:

src/jdk.hotspot.agent/linux/native/libsaproc/LinuxDebuggerLocal.cpp
src/jdk.hotspot.agent/macosx/native/libsaproc/MacosxDebuggerLocal.m
src/jdk.hotspot.agent/windows/native/libsaproc/sawindbg.cpp

-Instead of throwing an exception when the OS ThreadID is invalid, print a warning.

src/jdk.hotspot.agent/linux/native/libsaproc/ps_proc.c
-Improve a print_debug message

src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/debugger/bsd/BsdThread.java src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/debugger/linux/LinuxThread.java src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/debugger/windbg/amd64/WindbgAMD64Thread.java -Deal with the array of registers read in being null due to the OS ThreadID not being valid.

src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/debugger/bsd/BsdDebuggerLocal.java src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/debugger/linux/LinuxDebuggerLocal.java -Fix issue with "sun.jvm.hotspot.debugger.DebuggerException" appearing twice when printing the exception.

thanks,

Chris