Bug ID: JDK-6983930 CMS: Various small cleanups ca September 2010

Type: Enhancement
Component: hotspot
Sub-Component: gc
Affected Version: hs19

Priority: P4
Status: Closed
Resolution: Fixed
OS: generic
CPU: generic

Submitted: 2010-09-10
Updated: 2011-04-23
Resolved: 2011-04-23

JDK 6	JDK 7	Other
6u25Fixed	7Fixed	hs20Fixed

Small set of cleanups in CMS code:
(1) convert some guarantee()s to assert()s
(2) fix typos in comments/documentation etc.

EVALUATION http://hg.openjdk.java.net/jdk7/hotspot-rt/hotspot/rev/179464550c7d
20-09-2010
EVALUATION http://hg.openjdk.java.net/jdk7/hotspot-gc/hotspot/rev/179464550c7d
11-09-2010
EVALUATION Yup!
10-09-2010
SUGGESTED FIX diff -r dee553c74493 src/share/vm/gc_implementation/concurrentMarkSweep/binaryTreeDictionary.cpp --- a/src/share/vm/gc_implementation/concurrentMarkSweep/binaryTreeDictionary.cpp Wed Sep 01 00:40:05 2010 -0700 +++ b/src/share/vm/gc_implementation/concurrentMarkSweep/binaryTreeDictionary.cpp Fri Sep 10 11:23:51 2010 -0700 @@ -256,7 +256,7 @@ TreeChunk* TreeList::head_as_TreeChunk() } TreeChunk* TreeList::first_available() { - guarantee(head() != NULL, "The head of the list cannot be NULL"); + assert(head() != NULL, "The head of the list cannot be NULL"); FreeChunk* fc = head()->next(); TreeChunk* retTC; if (fc == NULL) { @@ -272,7 +272,7 @@ TreeChunk* TreeList::first_available() { // those in the list for this size; potentially slow and expensive, // use with caution! TreeChunk* TreeList::largest_address() { - guarantee(head() != NULL, "The head of the list cannot be NULL"); + assert(head() != NULL, "The head of the list cannot be NULL"); FreeChunk* fc = head()->next(); TreeChunk* retTC; if (fc == NULL) { diff -r dee553c74493 src/share/vm/gc_implementation/concurrentMarkSweep/compactibleFreeListSpace.cpp --- a/src/share/vm/gc_implementation/concurrentMarkSweep/compactibleFreeListSpace.cpp Wed Sep 01 00:40:05 2010 -0700 +++ b/src/share/vm/gc_implementation/concurrentMarkSweep/compactibleFreeListSpace.cpp Fri Sep 10 11:23:51 2010 -0700 @@ -1946,8 +1946,8 @@ void CompactibleFreeListSpace::save_mark bool CompactibleFreeListSpace::no_allocs_since_save_marks() { assert(_promoInfo.tracking(), "No preceding save_marks?"); - guarantee(SharedHeap::heap()->n_par_threads() == 0, - "Shouldn't be called (yet) during parallel part of gc."); + assert(SharedHeap::heap()->n_par_threads() == 0, + "Shouldn't be called if using parallel gc."); return _promoInfo.noPromotions(); } @@ -2569,7 +2569,7 @@ void CFLS_LAB::modify_initialization(siz HeapWord* CFLS_LAB::alloc(size_t word_sz) { FreeChunk* res; - guarantee(word_sz == _cfls->adjustObjectSize(word_sz), "Error"); + assert(word_sz == _cfls->adjustObjectSize(word_sz), "Error"); if (word_sz >= CompactibleFreeListSpace::IndexSetSize) { // This locking manages sync with other large object allocations. MutexLockerEx x(_cfls->parDictionaryAllocLock(), diff -r dee553c74493 src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.cpp --- a/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.cpp Wed Sep 01 00:40:05 2010 -070 0 +++ b/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.cpp Fri Sep 10 11:23:51 2010 -070 0 @@ -1332,7 +1332,7 @@ ConcurrentMarkSweepGeneration::allocatio // ----------------------------------------------------- // FREE: klass_word & 1 == 1; mark_word holds block size // -// OBJECT: klass_word installed; klass_word != 0 && klass_word & 0 == 0; +// OBJECT: klass_word installed; klass_word != 0 && klass_word & 1 == 0; // obj->size() computes correct size // [Perm Gen objects needs to be "parsable" before they can be navigated] // diff -r dee553c74493 src/share/vm/gc_implementation/concurrentMarkSweep/freeList.cpp --- a/src/share/vm/gc_implementation/concurrentMarkSweep/freeList.cpp Wed Sep 01 00:40:05 2010 -0700 +++ b/src/share/vm/gc_implementation/concurrentMarkSweep/freeList.cpp Fri Sep 10 11:23:51 2010 -0700 @@ -165,13 +165,8 @@ void FreeList::removeChunk(FreeChunkfc) "Next of tail should be NULL"); } decrement_count(); -#define TRAP_CODE 1 -#if TRAP_CODE - if (head() == NULL) { - guarantee(tail() == NULL, "INVARIANT"); - guarantee(count() == 0, "INVARIANT"); - } -#endif + assert(((head() == NULL) + (tail() == NULL) + (count() == 0)) % 3 == 0, + "H/T/C Inconsistency"); // clear next and prev fields of fc, debug only NOT_PRODUCT( fc->linkPrev(NULL); diff -r dee553c74493 src/share/vm/gc_implementation/concurrentMarkSweep/promotionInfo.cpp --- a/src/share/vm/gc_implementation/concurrentMarkSweep/promotionInfo.cpp Wed Sep 01 00:40:05 2010 -0700 +++ b/src/share/vm/gc_implementation/concurrentMarkSweep/promotionInfo.cpp Fri Sep 10 11:23:51 2010 -0700 @@ -253,8 +253,8 @@ void PromotionInfo::print_statistics(uin cur_spool = cur_spool->nextSpoolBlock) { // the first entry is just a self-pointer; indices 1 through // bufferSize - 1 are occupied (thus, bufferSize - 1 slots). - guarantee((void)cur_spool->displacedHdr == (void)&cur_spool->displacedHdr, - "first entry of displacedHdr should be self-referential"); + assert((void)cur_spool->displacedHdr == (void*)&cur_spool->displacedHdr, + "first entry of displacedHdr should be self-referential"); slots += cur_spool->bufferSize - 1; blocks++; } diff -r dee553c74493 src/share/vm/runtime/globals.hpp --- a/src/share/vm/runtime/globals.hpp Wed Sep 01 00:40:05 2010 -0700 +++ b/src/share/vm/runtime/globals.hpp Fri Sep 10 11:23:51 2010 -0700 @@ -1541,13 +1541,13 @@ class CommandLineFlags { "Use BinaryTreeDictionary as default in the CMS generation") \ \ product(uintx, CMSIndexedFreeListReplenish, 4, \ - "Replenish and indexed free list with this number of chunks") \ + "Replenish an indexed free list with this number of chunks") \ \ product(bool, CMSReplenishIntermediate, true, \ "Replenish all intermediate free-list caches") \ \ product(bool, CMSSplitIndexedFreeListBlocks, true, \ - "When satisfying batched demand, splot blocks from the " \ + "When satisfying batched demand, split blocks from the " \ "IndexedFreeList whose size is a multiple of requested size") \ \ product(bool, CMSLoopWarn, false, \
10-09-2010