Mercurial > hg > graal-compiler
diff src/share/vm/memory/blockOffsetTable.inline.hpp @ 1716:be3f9c242c9d
6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
Summary: GC workers now recognize an intermediate transient state of blocks which are allocated but have not yet completed initialization. blk_start() calls do not attempt to determine the size of a block in the transient state, rather waiting for the block to become initialized so that it is safe to query its size. Audited and ensured the order of initialization of object fields (klass, free bit and size) to respect block state transition protocol. Also included some new assertion checking code enabled in debug mode.
Reviewed-by: chrisphi, johnc, poonam
| author | ysr |
|---|---|
| date | Mon, 16 Aug 2010 15:58:42 -0700 |
| parents | c18cbe5936b8 |
| children | f95d63e2154a |
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--- a/src/share/vm/memory/blockOffsetTable.inline.hpp Sat Aug 14 00:47:52 2010 -0700 +++ b/src/share/vm/memory/blockOffsetTable.inline.hpp Mon Aug 16 15:58:42 2010 -0700 @@ -1,5 +1,5 @@ /* - * Copyright (c) 2000, 2002, Oracle and/or its affiliates. All rights reserved. + * Copyright (c) 2000, 2010, 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 @@ -55,10 +55,22 @@ return result; } +inline void BlockOffsetSharedArray::check_reducing_assertion(bool reducing) { + assert(reducing || !SafepointSynchronize::is_at_safepoint() || init_to_zero() || + Thread::current()->is_VM_thread() || + Thread::current()->is_ConcurrentGC_thread() || + ((!Thread::current()->is_ConcurrentGC_thread()) && + ParGCRareEvent_lock->owned_by_self()), "Crack"); +} ////////////////////////////////////////////////////////////////////////// // BlockOffsetArrayNonContigSpace inlines ////////////////////////////////////////////////////////////////////////// +inline void BlockOffsetArrayNonContigSpace::freed(HeapWord* blk, + size_t size) { + freed(blk, blk + size); +} + inline void BlockOffsetArrayNonContigSpace::freed(HeapWord* blk_start, HeapWord* blk_end) { // Verify that the BOT shows [blk_start, blk_end) to be one block.