RFR: 8199067 [REDO] NMT: Enhance thread stack tracking

[Zhengyu Gu]

Thanks, Thomas.

-Zhengyu

On 04/12/2018 04:22 PM, Thomas Stüfe wrote:
> Hi Zhengyu,
> 
> Looks fine now!
> 
> Thanks Thomas
> 
> On Thu 12. Apr 2018 at 22:13, Zhengyu Gu <zgu at redhat.com 
> <mailto:zgu at redhat.com>> wrote:
> 
>     Hi Thomas,
> 
>     Thanks for the review.
> 
>     On 04/11/2018 10:38 AM, Thomas Stüfe wrote:
>      > Hi Zhengyu,
>      >
>      > sorry for the late response!
>      >
>      > I looked the windows changes over.
>      >
>      > The capping of the size may not work correctly if the committed range
>      > overlaps the end of the region but starts in the middle:
>      >
>      > +    // current region may go beyond the limit, trim to the limit
>      > +    committed_size = MIN2(committed_size, size);
>      >
>      > should it not be rather:
>      >
>      > +    committed_size = MIN2(committed_size, top - committed_start);
>      >
>      > ?
>      >
>      > The code also assumes that the input range starts at the begin of a
>      > region. Not sure if this is always the case. So, I would test if
>      > MEMORY_BASIC_INFORMATION.BaseAddress lays below the input start
>      > address, in which case I would only add the overlapping part to the
>      > committed size.
> 
>     My bad. When I converted the method from thread stack specific one to
>     this general one, I did not think through and make corresponding
>     changes. Thanks for catching this.
> 
>     I renamed gtest test to reflect that it is no longer thread stack
>     specific, and added test cases for it.
> 
>     Updated webrev:
>     http://cr.openjdk.java.net/~zgu/8199067/webrev.01/index.html
> 
>     Test:
>         hotspot_runtime and gtest on Linux x64 (fastdebug and release)
>                                      Windows x64 (fastdebug and release)
> 
>     Thanks,
> 
>     -Zhengyu
> 
> 
> 
> 
> 
>      >
>      > Best Regards, Thomas
>      >
>      >
>      >
>      >
>      >
>      >
>      > On Mon, Mar 19, 2018 at 5:10 PM, Zhengyu Gu <zgu at redhat.com
>     <mailto:zgu at redhat.com>> wrote:
>      >>
>      >> Ping!
>      >>
>      >> submit-hs test still good.
>      >>
>      >> Mach5 mach5-one-zgu-JDK-8199067-20180319-1419-14981: Builds
>     PASSED. Testing SUCCESSFUL.
>      >>
>      >> Thanks,
>      >>
>      >> -Zhengyu
>      >>
>      >>
>      >> On 03/08/2018 09:08 AM, Zhengyu Gu wrote:
>      >>>
>      >>> The early change failed on some fast machine with many
>     processors running Linux OS. It reveals that there can be holes in
>     thread's stack, which throws off binary search for finding stack bottom.
>      >>>
>      >>> Besides, some threads (ConcurrentGCThread and WatcherThread,
>     etc.) do exit without notifying NMT, which can trip over NMT final
>     reporting, as their stacks became unmapped.
>      >>>
>      >>> This patch addresses above issues by searching whole address
>     range for committed regions. If the address range becomes invalid,
>     simply reports as not committed.
>      >>>
>      >>> GTest also updated.
>      >>>
>      >>> Bug: https://bugs.openjdk.java.net/browse/JDK-8199067
>      >>> Webrev:
>     http://cr.openjdk.java.net/~zgu/8199067/webrev.00/index.html
>      >>>
>      >>>
>      >>> Test:
>      >>>     hotspot tier1 on Linux 64 and Windows x64.
>      >>>
>      >>>     Submit repo test came back clean.
>      >>>     Mach5 mach5-one-zgu-JDK-8199067-20180308-1218-13719: Builds
>     PASSED. Testing SUCCESSFUL.
>      >>>
>      >>>
>      >>> Thanks,
>      >>>
>      >>> -Zhengyu
>      >>>
>