hg: jdk7/hotspot-gc/hotspot: 6987703: iCMS: Intermittent hang with gc/gctests/CallGC/CallGC01 and +ExplicitGCInvokesConcurrent

[y.s.ramakrishna at oracle.com]

Changeset: a181f3a124dd
Author:    ysr
Date:      2011-03-14 21:52 -0700
URL:       http://hg.openjdk.java.net/jdk7/hotspot-gc/hotspot/rev/a181f3a124dd

6987703: iCMS: Intermittent hang with gc/gctests/CallGC/CallGC01 and +ExplicitGCInvokesConcurrent
Summary: Count enable_icms() and disable_icms() events so as to prevent inteference between concurrent calls, which can cause the iCMS thread to be left stranded in icms_wait() with an unserviced request and no young allocations to unwedge it.
Reviewed-by: jcoomes, poonam

! src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.cpp
! src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepThread.cpp
! src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepThread.hpp
! src/share/vm/gc_implementation/concurrentMarkSweep/vmCMSOperations.cpp
! src/share/vm/gc_implementation/concurrentMarkSweep/vmCMSOperations.hpp