/* * Copyright (c) 1999, 2015, 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_GC_SHARED_THREADLOCALALLOCBUFFER_INLINE_HPP #define SHARE_VM_GC_SHARED_THREADLOCALALLOCBUFFER_INLINE_HPP #include "gc/shared/collectedHeap.hpp" #include "gc/shared/threadLocalAllocBuffer.hpp" #include "logging/log.hpp" #include "runtime/thread.hpp" #include "utilities/copy.hpp" inline HeapWord* ThreadLocalAllocBuffer::allocate(size_t size) { invariants(); HeapWord* obj = top(); if (pointer_delta(end(), obj) >= size) { // successful thread-local allocation #ifdef ASSERT // Skip mangling the space corresponding to the object header to // ensure that the returned space is not considered parsable by // any concurrent GC thread. size_t hdr_size = oopDesc::header_size(); Copy::fill_to_words(obj + hdr_size, size - hdr_size, badHeapWordVal); #endif // ASSERT // This addition is safe because we know that top is // at least size below end, so the add can't wrap. set_top(obj + size); invariants(); return obj; } return NULL; } inline size_t ThreadLocalAllocBuffer::compute_size(size_t obj_size) { const size_t aligned_obj_size = align_object_size(obj_size); // Compute the size for the new TLAB. // The "last" tlab may be smaller to reduce fragmentation. // unsafe_max_tlab_alloc is just a hint. const size_t available_size = Universe::heap()->unsafe_max_tlab_alloc(myThread()) / HeapWordSize; size_t new_tlab_size = MIN2(available_size, desired_size() + aligned_obj_size); // Make sure there's enough room for object and filler int[]. const size_t obj_plus_filler_size = aligned_obj_size + alignment_reserve(); if (new_tlab_size < obj_plus_filler_size) { // If there isn't enough room for the allocation, return failure. log_trace(gc, tlab)("ThreadLocalAllocBuffer::compute_size(" SIZE_FORMAT ") returns failure", obj_size); return 0; } log_trace(gc, tlab)("ThreadLocalAllocBuffer::compute_size(" SIZE_FORMAT ") returns " SIZE_FORMAT, obj_size, new_tlab_size); return new_tlab_size; } void ThreadLocalAllocBuffer::record_slow_allocation(size_t obj_size) { // Raise size required to bypass TLAB next time. Why? Else there's // a risk that a thread that repeatedly allocates objects of one // size will get stuck on this slow path. set_refill_waste_limit(refill_waste_limit() + refill_waste_limit_increment()); _slow_allocations++; log_develop_trace(gc, tlab)("TLAB: %s thread: " INTPTR_FORMAT " [id: %2d]" " obj: " SIZE_FORMAT " free: " SIZE_FORMAT " waste: " SIZE_FORMAT, "slow", p2i(myThread()), myThread()->osthread()->thread_id(), obj_size, free(), refill_waste_limit()); } #endif // SHARE_VM_GC_SHARED_THREADLOCALALLOCBUFFER_INLINE_HPP