/*

 * Copyright (c) 2015, 2017, 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.

 */

#include "precompiled.hpp"

#include "gc/shared/collectedHeap.hpp"

#include "gc/z/zAddress.inline.hpp"

#include "gc/z/zForwardingTable.inline.hpp"

#include "gc/z/zHeap.inline.hpp"

#include "gc/z/zLiveMap.inline.hpp"

#include "gc/z/zMark.hpp"

#include "gc/z/zPage.inline.hpp"

#include "gc/z/zPhysicalMemory.inline.hpp"

#include "gc/z/zStat.hpp"

#include "gc/z/zThread.hpp"

#include "gc/z/zUtils.inline.hpp"

#include "logging/log.hpp"

#include "runtime/orderAccess.hpp"

#include "utilities/align.hpp"

#include "utilities/debug.hpp"

#include "utilities/globalDefinitions.hpp"

static const ZStatCounter ZCounterRelocationContention("Contention", "Relocation Contention", ZStatUnitOpsPerSecond);

ZPage::ZPage(uint8_t type, ZVirtualMemory vmem, ZPhysicalMemory pmem) :

    _type(type),

    _pinned(0),

    _numa_id((uint8_t)-1),

    _seqnum(0),

    _virtual(vmem),

    _top(start()),

    _livemap(object_max_count()),

    _refcount(0),

    _forwarding(),

    _physical(pmem) {

  assert(!_physical.is_null(), "Should not be null");

  assert(!_virtual.is_null(), "Should not be null");

  assert((type == ZPageTypeSmall && size() == ZPageSizeSmall) ||

         (type == ZPageTypeMedium && size() == ZPageSizeMedium) ||

         (type == ZPageTypeLarge && is_aligned(size(), ZPageSizeMin)),

         "Page type/size mismatch");

}

ZPage::~ZPage() {

  assert(!is_active(), "Should not be active");

  assert(is_detached(), "Should be detached");

}

void ZPage::reset() {

  assert(!is_active(), "Should not be active");

  assert(!is_pinned(), "Should not be pinned");

  assert(!is_detached(), "Should not be detached");

  _seqnum = ZGlobalSeqNum;

  _top = start();

  _livemap.reset();

  // Make sure we don't make the page active before

  // the reset of the above fields are visible.

  OrderAccess::storestore();

  _refcount = 1;

}

uintptr_t ZPage::relocate_object_inner(uintptr_t from_index, uintptr_t from_offset) {

  ZForwardingTableCursor cursor;

  // Lookup address in forwarding table

  const ZForwardingTableEntry entry = _forwarding.find(from_index, &cursor);

  if (entry.from_index() == from_index) {

    // Already relocated, return new address

    return entry.to_offset();

  }

  // Not found in forwarding table, relocate object

  assert(is_object_marked(from_offset), "Should be marked");

  if (is_pinned()) {

    // In-place forward

    return _forwarding.insert(from_index, from_offset, &cursor);

  }

  // Allocate object

  const uintptr_t from_good = ZAddress::good(from_offset);

  const size_t size = ZUtils::object_size(from_good);

  const uintptr_t to_good = ZHeap::heap()->alloc_object_for_relocation(size);

  if (to_good == 0) {

    // Failed, in-place forward

    return _forwarding.insert(from_index, from_offset, &cursor);

  }

  // Copy object

  ZUtils::object_copy(from_good, to_good, size);

  // Update forwarding table

  const uintptr_t to_offset = ZAddress::offset(to_good);

  const uintptr_t to_offset_final = _forwarding.insert(from_index, to_offset, &cursor);

  if (to_offset_final == to_offset) {

    // Relocation succeeded

    return to_offset;

  }

  // Relocation contention

  ZStatInc(ZCounterRelocationContention);

  log_trace(gc)("Relocation contention, thread: " PTR_FORMAT " (%s), page: " PTR_FORMAT

                ", entry: " SIZE_FORMAT ", oop: " PTR_FORMAT ", size: " SIZE_FORMAT,

                ZThread::id(), ZThread::name(), p2i(this), cursor, from_good, size);

  // Try undo allocation

  ZHeap::heap()->undo_alloc_object_for_relocation(to_good, size);

  return to_offset_final;

}

uintptr_t ZPage::relocate_object(uintptr_t from) {

  assert(ZHeap::heap()->is_relocating(from), "Should be relocating");

  const uintptr_t from_offset = ZAddress::offset(from);

  const uintptr_t from_index = (from_offset - start()) >> object_alignment_shift();

  const uintptr_t to_offset = relocate_object_inner(from_index, from_offset);

  if (from_offset == to_offset) {

    // In-place forwarding, pin page

    set_pinned();

  }

  return ZAddress::good(to_offset);

}

uintptr_t ZPage::forward_object(uintptr_t from) {

  assert(ZHeap::heap()->is_relocating(from), "Should be relocated");

  // Lookup address in forwarding table

  const uintptr_t from_offset = ZAddress::offset(from);

  const uintptr_t from_index = (from_offset - start()) >> object_alignment_shift();

  const ZForwardingTableEntry entry = _forwarding.find(from_index);

  assert(entry.from_index() == from_index, "Should be forwarded");

  return ZAddress::good(entry.to_offset());

}

void ZPage::print_on(outputStream* out) const {

  out->print_cr(" %-6s  " PTR_FORMAT " " PTR_FORMAT " " PTR_FORMAT " %s%s%s%s%s%s",

                type_to_string(), start(), top(), end(),

                is_allocating()  ? " Allocating"  : "",

                is_relocatable() ? " Relocatable" : "",

                is_forwarding()  ? " Forwarding"  : "",

                is_pinned()      ? " Pinned"      : "",

                is_detached()    ? " Detached"    : "",

                !is_active()     ? " Inactive"    : "");

}

void ZPage::print() const {

  print_on(tty);

}