Mon, 26 Jan 2009 12:47:21 -0800
6786503: Overflow list performance can be improved
Summary: Avoid overflow list walk in CMS & ParNew when it is unnecessary. Fix a couple of correctness issues, including a C-heap leak, in ParNew at the intersection of promotion failure, work queue overflow and object array chunking. Add stress testing option and related assertion checking.
Reviewed-by: jmasa
duke@435 | 1 | /* |
duke@435 | 2 | * Copyright 2000-2006 Sun Microsystems, Inc. All Rights Reserved. |
duke@435 | 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
duke@435 | 4 | * |
duke@435 | 5 | * This code is free software; you can redistribute it and/or modify it |
duke@435 | 6 | * under the terms of the GNU General Public License version 2 only, as |
duke@435 | 7 | * published by the Free Software Foundation. |
duke@435 | 8 | * |
duke@435 | 9 | * This code is distributed in the hope that it will be useful, but WITHOUT |
duke@435 | 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
duke@435 | 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
duke@435 | 12 | * version 2 for more details (a copy is included in the LICENSE file that |
duke@435 | 13 | * accompanied this code). |
duke@435 | 14 | * |
duke@435 | 15 | * You should have received a copy of the GNU General Public License version |
duke@435 | 16 | * 2 along with this work; if not, write to the Free Software Foundation, |
duke@435 | 17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
duke@435 | 18 | * |
duke@435 | 19 | * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
duke@435 | 20 | * CA 95054 USA or visit www.sun.com if you need additional information or |
duke@435 | 21 | * have any questions. |
duke@435 | 22 | * |
duke@435 | 23 | */ |
duke@435 | 24 | |
ysr@777 | 25 | inline HeapWord* Space::block_start(const void* p) { |
ysr@777 | 26 | return block_start_const(p); |
ysr@777 | 27 | } |
ysr@777 | 28 | |
duke@435 | 29 | inline HeapWord* OffsetTableContigSpace::allocate(size_t size) { |
duke@435 | 30 | HeapWord* res = ContiguousSpace::allocate(size); |
duke@435 | 31 | if (res != NULL) { |
duke@435 | 32 | _offsets.alloc_block(res, size); |
duke@435 | 33 | } |
duke@435 | 34 | return res; |
duke@435 | 35 | } |
duke@435 | 36 | |
duke@435 | 37 | // Because of the requirement of keeping "_offsets" up to date with the |
duke@435 | 38 | // allocations, we sequentialize these with a lock. Therefore, best if |
duke@435 | 39 | // this is used for larger LAB allocations only. |
duke@435 | 40 | inline HeapWord* OffsetTableContigSpace::par_allocate(size_t size) { |
duke@435 | 41 | MutexLocker x(&_par_alloc_lock); |
duke@435 | 42 | // This ought to be just "allocate", because of the lock above, but that |
duke@435 | 43 | // ContiguousSpace::allocate asserts that either the allocating thread |
duke@435 | 44 | // holds the heap lock or it is the VM thread and we're at a safepoint. |
duke@435 | 45 | // The best I (dld) could figure was to put a field in ContiguousSpace |
duke@435 | 46 | // meaning "locking at safepoint taken care of", and set/reset that |
duke@435 | 47 | // here. But this will do for now, especially in light of the comment |
duke@435 | 48 | // above. Perhaps in the future some lock-free manner of keeping the |
duke@435 | 49 | // coordination. |
duke@435 | 50 | HeapWord* res = ContiguousSpace::par_allocate(size); |
duke@435 | 51 | if (res != NULL) { |
duke@435 | 52 | _offsets.alloc_block(res, size); |
duke@435 | 53 | } |
duke@435 | 54 | return res; |
duke@435 | 55 | } |
duke@435 | 56 | |
ysr@777 | 57 | inline HeapWord* |
ysr@777 | 58 | OffsetTableContigSpace::block_start_const(const void* p) const { |
duke@435 | 59 | return _offsets.block_start(p); |
duke@435 | 60 | } |
duke@435 | 61 | |
duke@435 | 62 | inline HeapWord* ContiguousSpace::concurrent_iteration_safe_limit() |
duke@435 | 63 | { |
duke@435 | 64 | assert(_concurrent_iteration_safe_limit <= top(), |
duke@435 | 65 | "_concurrent_iteration_safe_limit update missed"); |
duke@435 | 66 | return _concurrent_iteration_safe_limit; |
duke@435 | 67 | } |
duke@435 | 68 | |
duke@435 | 69 | inline void ContiguousSpace::set_concurrent_iteration_safe_limit(HeapWord* new_limit) |
duke@435 | 70 | { |
duke@435 | 71 | assert(new_limit <= top(), "uninitialized objects in the safe range"); |
duke@435 | 72 | _concurrent_iteration_safe_limit = new_limit; |
duke@435 | 73 | } |