Mercurial > hg > graal-jvmci-8
view src/share/vm/memory/allocation.inline.hpp @ 3917:eca1193ca245
4965777: GC changes to support use of discovered field for pending references
Summary: If and when the reference handler thread is able to use the discovered field to link reference objects in its pending list, so will GC. In that case, GC will scan through this field once a reference object has been placed on the pending list, but not scan that field before that stage, as the field is used by the concurrent GC thread to link discovered objects. When ReferenceHandleR thread does not use the discovered field for the purpose of linking the elements in the pending list, as would be the case in older JDKs, the JVM will fall back to the old behaviour of using the next field for that purpose.
Reviewed-by: jcoomes, mchung, stefank
author | ysr |
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date | Wed, 07 Sep 2011 13:55:42 -0700 |
parents | bf29934d2f4f |
children | d2a62e0f25eb |
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/* * Copyright (c) 1997, 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 * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ #ifndef SHARE_VM_MEMORY_ALLOCATION_INLINE_HPP #define SHARE_VM_MEMORY_ALLOCATION_INLINE_HPP #include "runtime/os.hpp" // Explicit C-heap memory management void trace_heap_malloc(size_t size, const char* name, void *p); void trace_heap_free(void *p); #ifndef PRODUCT // Increments unsigned long value for statistics (not atomic on MP). inline void inc_stat_counter(volatile julong* dest, julong add_value) { #if defined(SPARC) || defined(X86) // Sparc and X86 have atomic jlong (8 bytes) instructions julong value = Atomic::load((volatile jlong*)dest); value += add_value; Atomic::store((jlong)value, (volatile jlong*)dest); #else // possible word-tearing during load/store *dest += add_value; #endif } #endif // allocate using malloc; will fail if no memory available inline char* AllocateHeap(size_t size, const char* name = NULL) { char* p = (char*) os::malloc(size); #ifdef ASSERT if (PrintMallocFree) trace_heap_malloc(size, name, p); #else Unused_Variable(name); #endif if (p == NULL) vm_exit_out_of_memory(size, name); return p; } inline char* ReallocateHeap(char *old, size_t size, const char* name = NULL) { char* p = (char*) os::realloc(old,size); #ifdef ASSERT if (PrintMallocFree) trace_heap_malloc(size, name, p); #else Unused_Variable(name); #endif if (p == NULL) vm_exit_out_of_memory(size, name); return p; } inline void FreeHeap(void* p) { #ifdef ASSERT if (PrintMallocFree) trace_heap_free(p); #endif os::free(p); } #endif // SHARE_VM_MEMORY_ALLOCATION_INLINE_HPP