archive/jdk
1
0
Fork 0
mirror of https://github.com/openjdk/jdk.git synced 2025-08-27 23:04:50 +02:00
Code Issues Projects Releases Packages Wiki Activity Actions

6987703: iCMS: Intermittent hang with gc/gctests/CallGC/CallGC01 and +ExplicitGCInvokesConcurrent

Browse source 
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
This commit is contained in:
Y. Srinivas Ramakrishna 2011-03-14 21:52:24 -07:00
parent edb9e105eb
commit a3de65241c
5 changed files with 44 additions and 20 deletions
Download patch file Download diff file Expand all files Collapse all files

31
hotspot/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepThread.hpp
View file

@ -1,5 +1,5 @@
/*
* Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2001, 2011, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@ -40,7 +40,7 @@
class ConcurrentMarkSweepGeneration;
class CMSCollector;
// The Concurrent Mark Sweep GC Thread (could be several in the future).
// The Concurrent Mark Sweep GC Thread
class ConcurrentMarkSweepThread: public ConcurrentGCThread {
friend class VMStructs;
friend class ConcurrentMarkSweepGeneration; // XXX should remove friendship
@ -55,8 +55,6 @@ class ConcurrentMarkSweepThread: public ConcurrentGCThread {
static SurrogateLockerThread::SLT_msg_type _sltBuffer;
static Monitor* _sltMonitor;
ConcurrentMarkSweepThread* _next;
static bool _should_terminate;
enum CMS_flag_type {
@ -84,7 +82,7 @@ class ConcurrentMarkSweepThread: public ConcurrentGCThread {
// Tracing messages, enabled by CMSTraceThreadState.
static inline void trace_state(const char* desc);
static volatile bool _icms_enabled; // iCMS enabled?
static volatile int _icms_disabled; // a counter to track #iCMS disable & enable
static volatile bool _should_run; // iCMS may run
static volatile bool _should_stop; // iCMS should stop
@ -214,10 +212,25 @@ class ConcurrentMarkSweepThread: public ConcurrentGCThread {
// Incremental mode is enabled globally by the flag CMSIncrementalMode. It
// must also be enabled/disabled dynamically to allow foreground collections.
static inline void enable_icms() { _icms_enabled = true; }
static inline void disable_icms() { _icms_enabled = false; }
static inline void set_icms_enabled(bool val) { _icms_enabled = val; }
static inline bool icms_enabled() { return _icms_enabled; }
#define ICMS_ENABLING_ASSERT \
assert((CMSIncrementalMode && _icms_disabled >= 0) || \
(!CMSIncrementalMode && _icms_disabled <= 0), "Error")
static inline void enable_icms() {
ICMS_ENABLING_ASSERT;
Atomic::dec(&_icms_disabled);
}
static inline void disable_icms() {
ICMS_ENABLING_ASSERT;
Atomic::inc(&_icms_disabled);
}
static inline bool icms_is_disabled() {
ICMS_ENABLING_ASSERT;
return _icms_disabled > 0;
}
static inline bool icms_is_enabled() {
return !icms_is_disabled();
}
};
inline void ConcurrentMarkSweepThread::trace_state(const char* desc) {