mutableSpace.cpp revision 11857:d0fbf661cc16
1254721Semaste/* 2254721Semaste * Copyright (c) 2001, 2016, Oracle and/or its affiliates. All rights reserved. 3254721Semaste * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4254721Semaste * 5254721Semaste * This code is free software; you can redistribute it and/or modify it 6254721Semaste * under the terms of the GNU General Public License version 2 only, as 7254721Semaste * published by the Free Software Foundation. 8254721Semaste * 9254721Semaste * This code is distributed in the hope that it will be useful, but WITHOUT 10254721Semaste * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11254721Semaste * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12254721Semaste * version 2 for more details (a copy is included in the LICENSE file that 13296417Sdim * accompanied this code). 14296417Sdim * 15296417Sdim * You should have received a copy of the GNU General Public License version 16296417Sdim * 2 along with this work; if not, write to the Free Software Foundation, 17254721Semaste * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18288943Sdim * 19314564Sdim * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20254721Semaste * or visit www.oracle.com if you need additional information or have any 21314564Sdim * questions. 22254721Semaste * 23254721Semaste */ 24288943Sdim 25254721Semaste#include "precompiled.hpp" 26254721Semaste#include "gc/parallel/mutableSpace.hpp" 27254721Semaste#include "gc/shared/spaceDecorator.hpp" 28254721Semaste#include "oops/oop.inline.hpp" 29254721Semaste#include "runtime/atomic.hpp" 30254721Semaste#include "runtime/safepoint.hpp" 31254721Semaste#include "runtime/thread.hpp" 32280031Sdim#include "utilities/macros.hpp" 33280031Sdim 34314564SdimMutableSpace::MutableSpace(size_t alignment): ImmutableSpace(), _top(NULL), _alignment(alignment) { 35254721Semaste assert(MutableSpace::alignment() % os::vm_page_size() == 0, 36314564Sdim "Space should be aligned"); 37314564Sdim _mangler = new MutableSpaceMangler(this); 38314564Sdim} 39314564Sdim 40314564SdimMutableSpace::~MutableSpace() { 41314564Sdim delete _mangler; 42314564Sdim} 43314564Sdim 44314564Sdimvoid MutableSpace::numa_setup_pages(MemRegion mr, bool clear_space) { 45314564Sdim if (!mr.is_empty()) { 46254721Semaste size_t page_size = UseLargePages ? alignment() : os::vm_page_size(); 47314564Sdim HeapWord *start = (HeapWord*)round_to((intptr_t) mr.start(), page_size); 48314564Sdim HeapWord *end = (HeapWord*)round_down((intptr_t) mr.end(), page_size); 49314564Sdim if (end > start) { 50314564Sdim size_t size = pointer_delta(end, start, sizeof(char)); 51254721Semaste if (clear_space) { 52314564Sdim // Prefer page reallocation to migration. 53254721Semaste os::free_memory((char*)start, size, page_size); 54314564Sdim } 55254721Semaste os::numa_make_global((char*)start, size); 56314564Sdim } 57314564Sdim } 58314564Sdim} 59314564Sdim 60296417Sdimvoid MutableSpace::pretouch_pages(MemRegion mr) { 61314564Sdim os::pretouch_memory(mr.start(), mr.end()); 62288943Sdim} 63314564Sdim 64288943Sdimvoid MutableSpace::initialize(MemRegion mr, 65314564Sdim bool clear_space, 66288943Sdim bool mangle_space, 67314564Sdim bool setup_pages) { 68288943Sdim 69314564Sdim assert(Universe::on_page_boundary(mr.start()) && Universe::on_page_boundary(mr.end()), 70254721Semaste "invalid space boundaries"); 71314564Sdim 72314564Sdim if (setup_pages && (UseNUMA || AlwaysPreTouch)) { 73254721Semaste // The space may move left and right or expand/shrink. 74314564Sdim // We'd like to enforce the desired page placement. 75280031Sdim MemRegion head, tail; 76314564Sdim if (last_setup_region().is_empty()) { 77296417Sdim // If it's the first initialization don't limit the amount of work. 78314564Sdim head = mr; 79314564Sdim tail = MemRegion(mr.end(), mr.end()); 80314564Sdim } else { 81314564Sdim // Is there an intersection with the address space? 82314564Sdim MemRegion intersection = last_setup_region().intersection(mr); 83314564Sdim if (intersection.is_empty()) { 84314564Sdim intersection = MemRegion(mr.end(), mr.end()); 85314564Sdim } 86314564Sdim // All the sizes below are in words. 87314564Sdim size_t head_size = 0, tail_size = 0; 88296417Sdim if (mr.start() <= intersection.start()) { 89314564Sdim head_size = pointer_delta(intersection.start(), mr.start()); 90314564Sdim } 91314564Sdim if(intersection.end() <= mr.end()) { 92314564Sdim tail_size = pointer_delta(mr.end(), intersection.end()); 93314564Sdim } 94314564Sdim // Limit the amount of page manipulation if necessary. 95314564Sdim if (NUMASpaceResizeRate > 0 && !AlwaysPreTouch) { 96314564Sdim const size_t change_size = head_size + tail_size; 97314564Sdim const float setup_rate_words = NUMASpaceResizeRate >> LogBytesPerWord; 98314564Sdim head_size = MIN2((size_t)(setup_rate_words * head_size / change_size), 99314564Sdim head_size); 100314564Sdim tail_size = MIN2((size_t)(setup_rate_words * tail_size / change_size), 101314564Sdim tail_size); 102314564Sdim } 103314564Sdim head = MemRegion(intersection.start() - head_size, intersection.start()); 104254721Semaste tail = MemRegion(intersection.end(), intersection.end() + tail_size); 105314564Sdim } 106314564Sdim assert(mr.contains(head) && mr.contains(tail), "Sanity"); 107314564Sdim 108314564Sdim if (UseNUMA) { 109314564Sdim numa_setup_pages(head, clear_space); 110314564Sdim numa_setup_pages(tail, clear_space); 111314564Sdim } 112314564Sdim 113314564Sdim if (AlwaysPreTouch) { 114314564Sdim pretouch_pages(head); 115314564Sdim pretouch_pages(tail); 116314564Sdim } 117314564Sdim 118314564Sdim // Remember where we stopped so that we can continue later. 119314564Sdim set_last_setup_region(MemRegion(head.start(), tail.end())); 120314564Sdim } 121314564Sdim 122314564Sdim set_bottom(mr.start()); 123314564Sdim set_end(mr.end()); 124314564Sdim 125314564Sdim if (clear_space) { 126314564Sdim clear(mangle_space); 127314564Sdim } 128314564Sdim} 129314564Sdim 130314564Sdimvoid MutableSpace::clear(bool mangle_space) { 131314564Sdim set_top(bottom()); 132314564Sdim if (ZapUnusedHeapArea && mangle_space) { 133314564Sdim mangle_unused_area(); 134314564Sdim } 135314564Sdim} 136314564Sdim 137314564Sdim#ifndef PRODUCT 138314564Sdimvoid MutableSpace::check_mangled_unused_area(HeapWord* limit) { 139314564Sdim mangler()->check_mangled_unused_area(limit); 140314564Sdim} 141314564Sdim 142314564Sdimvoid MutableSpace::check_mangled_unused_area_complete() { 143314564Sdim mangler()->check_mangled_unused_area_complete(); 144314564Sdim} 145314564Sdim 146314564Sdim// Mangle only the unused space that has not previously 147314564Sdim// been mangled and that has not been allocated since being 148314564Sdim// mangled. 149314564Sdimvoid MutableSpace::mangle_unused_area() { 150314564Sdim mangler()->mangle_unused_area(); 151314564Sdim} 152314564Sdim 153314564Sdimvoid MutableSpace::mangle_unused_area_complete() { 154314564Sdim mangler()->mangle_unused_area_complete(); 155314564Sdim} 156314564Sdim 157314564Sdimvoid MutableSpace::mangle_region(MemRegion mr) { 158314564Sdim SpaceMangler::mangle_region(mr); 159314564Sdim} 160314564Sdim 161314564Sdimvoid MutableSpace::set_top_for_allocations(HeapWord* v) { 162314564Sdim mangler()->set_top_for_allocations(v); 163314564Sdim} 164254721Semaste 165314564Sdimvoid MutableSpace::set_top_for_allocations() { 166314564Sdim mangler()->set_top_for_allocations(top()); 167314564Sdim} 168314564Sdim#endif 169314564Sdim 170314564Sdim// This version requires locking. */ 171314564SdimHeapWord* MutableSpace::allocate(size_t size) { 172314564Sdim assert(Heap_lock->owned_by_self() || 173314564Sdim (SafepointSynchronize::is_at_safepoint() && 174314564Sdim Thread::current()->is_VM_thread()), 175314564Sdim "not locked"); 176314564Sdim HeapWord* obj = top(); 177314564Sdim if (pointer_delta(end(), obj) >= size) { 178314564Sdim HeapWord* new_top = obj + size; 179314564Sdim set_top(new_top); 180314564Sdim assert(is_object_aligned((intptr_t)obj) && is_object_aligned((intptr_t)new_top), 181314564Sdim "checking alignment"); 182314564Sdim return obj; 183314564Sdim } else { 184314564Sdim return NULL; 185314564Sdim } 186314564Sdim} 187314564Sdim 188314564Sdim// This version is lock-free. 189314564SdimHeapWord* MutableSpace::cas_allocate(size_t size) { 190314564Sdim do { 191314564Sdim HeapWord* obj = top(); 192314564Sdim if (pointer_delta(end(), obj) >= size) { 193314564Sdim HeapWord* new_top = obj + size; 194314564Sdim HeapWord* result = (HeapWord*)Atomic::cmpxchg_ptr(new_top, top_addr(), obj); 195314564Sdim // result can be one of two: 196314564Sdim // the old top value: the exchange succeeded 197314564Sdim // otherwise: the new value of the top is returned. 198314564Sdim if (result != obj) { 199314564Sdim continue; // another thread beat us to the allocation, try again 200314564Sdim } 201314564Sdim assert(is_object_aligned((intptr_t)obj) && is_object_aligned((intptr_t)new_top), 202314564Sdim "checking alignment"); 203314564Sdim return obj; 204314564Sdim } else { 205314564Sdim return NULL; 206314564Sdim } 207314564Sdim } while (true); 208314564Sdim} 209314564Sdim 210314564Sdim// Try to deallocate previous allocation. Returns true upon success. 211314564Sdimbool MutableSpace::cas_deallocate(HeapWord *obj, size_t size) { 212314564Sdim HeapWord* expected_top = obj + size; 213314564Sdim return (HeapWord*)Atomic::cmpxchg_ptr(obj, top_addr(), expected_top) == expected_top; 214314564Sdim} 215314564Sdim 216314564Sdimvoid MutableSpace::oop_iterate_no_header(OopClosure* cl) { 217314564Sdim HeapWord* obj_addr = bottom(); 218314564Sdim HeapWord* t = top(); 219314564Sdim // Could call objects iterate, but this is easier. 220314564Sdim while (obj_addr < t) { 221254721Semaste obj_addr += oop(obj_addr)->oop_iterate_no_header(cl); 222314564Sdim } 223314564Sdim} 224314564Sdim 225314564Sdimvoid MutableSpace::object_iterate(ObjectClosure* cl) { 226314564Sdim HeapWord* p = bottom(); 227254721Semaste while (p < top()) { 228296417Sdim cl->do_object(oop(p)); 229314564Sdim p += oop(p)->size(); 230314564Sdim } 231314564Sdim} 232314564Sdim 233314564Sdimvoid MutableSpace::print_short() const { print_short_on(tty); } 234314564Sdimvoid MutableSpace::print_short_on( outputStream* st) const { 235314564Sdim st->print(" space " SIZE_FORMAT "K, %d%% used", capacity_in_bytes() / K, 236314564Sdim (int) ((double) used_in_bytes() * 100 / capacity_in_bytes())); 237314564Sdim} 238314564Sdim 239314564Sdimvoid MutableSpace::print() const { print_on(tty); } 240314564Sdimvoid MutableSpace::print_on(outputStream* st) const { 241314564Sdim MutableSpace::print_short_on(st); 242314564Sdim st->print_cr(" [" INTPTR_FORMAT "," INTPTR_FORMAT "," INTPTR_FORMAT ")", 243314564Sdim p2i(bottom()), p2i(top()), p2i(end())); 244314564Sdim} 245314564Sdim 246314564Sdimvoid MutableSpace::verify() { 247314564Sdim HeapWord* p = bottom(); 248314564Sdim HeapWord* t = top(); 249314564Sdim HeapWord* prev_p = NULL; 250314564Sdim while (p < t) { 251314564Sdim oop(p)->verify(); 252314564Sdim prev_p = p; 253254721Semaste p += oop(p)->size(); 254314564Sdim } 255314564Sdim guarantee(p == top(), "end of last object must match end of space"); 256314564Sdim} 257314564Sdim