8062870: src/share/vm/services/mallocTracker.hpp:64 assert(_count > 0) failed: Negative , counter

[Christian Tornqvist]

Hi Coleen,

As mentioned offline, please make sure you remove the @ignore from
test/runtime/NMT/MallocTrackingVerify.java as well.

Otherwise this looks good, thanks for fixing this.

Thanks,
Christian

-----Original Message-----
From: hotspot-runtime-dev
[mailto:hotspot-runtime-dev-bounces at openjdk.java.net] On Behalf Of Coleen
Phillimore
Sent: Monday, November 10, 2014 12:21 PM
To: hotspot-runtime-dev
Subject: RFR: 8062870: src/share/vm/services/mallocTracker.hpp:64
assert(_count > 0) failed: Negative ,counter

Summary: Signed bitfield size y can only have (1 << y)-1 values.

We were overflowing the the _pos index and reusing the 0th element in the
MallocSiteTable for two different stack traces which caused the assert for
deallocation.

Tested with nsk.quick.testlist and jtreg runtime tests with
-XX:NativeMemoryTracking=detail.

open webrev at http://cr.openjdk.java.net/~coleenp/8062870/
bug link https://bugs.openjdk.java.net/browse/JDK-8062870

Thanks,
Coleen