1 /* 2 * Copyright (c) 2018, Google and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "runtime/sharedRuntime.hpp" 26 #include "runtime/threadHeapSampler.hpp" 27 #include "runtime/heapMonitoring.hpp" 28 29 void ThreadHeapSampler::pick_next_sample(size_t overflowed_bytes) { 30 HeapMonitoring::pick_next_sample(&_bytes_until_sample); 31 32 // Try to correct sample size by removing extra space from last allocation. 33 if (overflowed_bytes > 0 && _bytes_until_sample > overflowed_bytes) { 34 _bytes_until_sample -= overflowed_bytes; 35 } 36 } 37 38 void ThreadHeapSampler::check_for_sampling(HeapWord* ptr, size_t allocation_size, size_t bytes_since_allocation) { 39 oopDesc* oop = reinterpret_cast<oopDesc*>(ptr); 40 size_t total_allocated_bytes = bytes_since_allocation + allocation_size; 41 42 // If not yet time for a sample, skip it. 43 if (total_allocated_bytes < _bytes_until_sample) { 44 _bytes_until_sample -= total_allocated_bytes; 45 return; 46 } 47 48 HeapMonitoring::object_alloc_do_sample(_thread, oop, allocation_size); 49 JvmtiExport::sampled_object_alloc_event_collector(oop); 50 51 size_t overflow_bytes = total_allocated_bytes - _bytes_until_sample; 52 pick_next_sample(overflow_bytes); 53 }