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/*
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* Copyright 1997-2005 Sun Microsystems, Inc. All Rights Reserved.
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* This code is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 only, as
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* published by the Free Software Foundation.
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*
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* This code is distributed in the hope that it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* version 2 for more details (a copy is included in the LICENSE file that
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* accompanied this code).
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*
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* You should have received a copy of the GNU General Public License version
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* 2 along with this work; if not, write to the Free Software Foundation,
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
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* CA 95054 USA or visit www.sun.com if you need additional information or
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* have any questions.
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*
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*/
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#include "incls/_precompiled.incl"
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#include "incls/_virtualspace.cpp.incl"
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// ReservedSpace
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ReservedSpace::ReservedSpace(size_t size) {
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initialize(size, 0, false, NULL);
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}
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ReservedSpace::ReservedSpace(size_t size, size_t alignment,
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bool large, char* requested_address) {
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initialize(size, alignment, large, requested_address);
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}
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char *
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ReservedSpace::align_reserved_region(char* addr, const size_t len,
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const size_t prefix_size,
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const size_t prefix_align,
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const size_t suffix_size,
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const size_t suffix_align)
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{
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assert(addr != NULL, "sanity");
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const size_t required_size = prefix_size + suffix_size;
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assert(len >= required_size, "len too small");
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const size_t s = size_t(addr);
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const size_t beg_ofs = s + prefix_size & suffix_align - 1;
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const size_t beg_delta = beg_ofs == 0 ? 0 : suffix_align - beg_ofs;
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if (len < beg_delta + required_size) {
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return NULL; // Cannot do proper alignment.
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}
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const size_t end_delta = len - (beg_delta + required_size);
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if (beg_delta != 0) {
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os::release_memory(addr, beg_delta);
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}
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if (end_delta != 0) {
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char* release_addr = (char*) (s + beg_delta + required_size);
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os::release_memory(release_addr, end_delta);
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}
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return (char*) (s + beg_delta);
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}
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char* ReservedSpace::reserve_and_align(const size_t reserve_size,
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const size_t prefix_size,
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const size_t prefix_align,
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const size_t suffix_size,
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const size_t suffix_align)
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{
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assert(reserve_size > prefix_size + suffix_size, "should not be here");
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char* raw_addr = os::reserve_memory(reserve_size, NULL, prefix_align);
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if (raw_addr == NULL) return NULL;
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char* result = align_reserved_region(raw_addr, reserve_size, prefix_size,
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prefix_align, suffix_size,
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suffix_align);
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if (result == NULL && !os::release_memory(raw_addr, reserve_size)) {
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fatal("os::release_memory failed");
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}
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#ifdef ASSERT
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if (result != NULL) {
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const size_t raw = size_t(raw_addr);
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const size_t res = size_t(result);
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assert(res >= raw, "alignment decreased start addr");
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assert(res + prefix_size + suffix_size <= raw + reserve_size,
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"alignment increased end addr");
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assert((res & prefix_align - 1) == 0, "bad alignment of prefix");
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assert((res + prefix_size & suffix_align - 1) == 0,
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"bad alignment of suffix");
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}
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#endif
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return result;
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}
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ReservedSpace::ReservedSpace(const size_t prefix_size,
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const size_t prefix_align,
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const size_t suffix_size,
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const size_t suffix_align)
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{
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assert(prefix_size != 0, "sanity");
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assert(prefix_align != 0, "sanity");
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assert(suffix_size != 0, "sanity");
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assert(suffix_align != 0, "sanity");
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assert((prefix_size & prefix_align - 1) == 0,
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"prefix_size not divisible by prefix_align");
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assert((suffix_size & suffix_align - 1) == 0,
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"suffix_size not divisible by suffix_align");
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assert((suffix_align & prefix_align - 1) == 0,
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"suffix_align not divisible by prefix_align");
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// On systems where the entire region has to be reserved and committed up
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// front, the compound alignment normally done by this method is unnecessary.
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const bool try_reserve_special = UseLargePages &&
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prefix_align == os::large_page_size();
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if (!os::can_commit_large_page_memory() && try_reserve_special) {
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initialize(prefix_size + suffix_size, prefix_align, true);
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return;
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}
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_base = NULL;
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_size = 0;
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_alignment = 0;
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_special = false;
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// Optimistically try to reserve the exact size needed.
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const size_t size = prefix_size + suffix_size;
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char* addr = os::reserve_memory(size, NULL, prefix_align);
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if (addr == NULL) return;
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// Check whether the result has the needed alignment (unlikely unless
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// prefix_align == suffix_align).
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const size_t ofs = size_t(addr) + prefix_size & suffix_align - 1;
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if (ofs != 0) {
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// Wrong alignment. Release, allocate more space and do manual alignment.
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//
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// On most operating systems, another allocation with a somewhat larger size
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// will return an address "close to" that of the previous allocation. The
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// result is often the same address (if the kernel hands out virtual
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// addresses from low to high), or an address that is offset by the increase
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// in size. Exploit that to minimize the amount of extra space requested.
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if (!os::release_memory(addr, size)) {
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fatal("os::release_memory failed");
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}
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const size_t extra = MAX2(ofs, suffix_align - ofs);
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addr = reserve_and_align(size + extra, prefix_size, prefix_align,
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suffix_size, suffix_align);
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if (addr == NULL) {
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// Try an even larger region. If this fails, address space is exhausted.
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addr = reserve_and_align(size + suffix_align, prefix_size,
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prefix_align, suffix_size, suffix_align);
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}
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}
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_base = addr;
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_size = size;
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_alignment = prefix_align;
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}
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void ReservedSpace::initialize(size_t size, size_t alignment, bool large,
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char* requested_address) {
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const size_t granularity = os::vm_allocation_granularity();
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assert((size & granularity - 1) == 0,
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"size not aligned to os::vm_allocation_granularity()");
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assert((alignment & granularity - 1) == 0,
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"alignment not aligned to os::vm_allocation_granularity()");
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assert(alignment == 0 || is_power_of_2((intptr_t)alignment),
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"not a power of 2");
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_base = NULL;
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_size = 0;
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_special = false;
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_alignment = 0;
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if (size == 0) {
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return;
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}
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// If OS doesn't support demand paging for large page memory, we need
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// to use reserve_memory_special() to reserve and pin the entire region.
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bool special = large && !os::can_commit_large_page_memory();
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char* base = NULL;
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if (special) {
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// It's not hard to implement reserve_memory_special() such that it can
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// allocate at fixed address, but there seems no use of this feature
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// for now, so it's not implemented.
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assert(requested_address == NULL, "not implemented");
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base = os::reserve_memory_special(size);
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if (base != NULL) {
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// Check alignment constraints
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if (alignment > 0) {
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assert((uintptr_t) base % alignment == 0,
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"Large pages returned a non-aligned address");
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}
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_special = true;
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} else {
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// failed; try to reserve regular memory below
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}
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}
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if (base == NULL) {
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// Optimistically assume that the OSes returns an aligned base pointer.
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// When reserving a large address range, most OSes seem to align to at
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// least 64K.
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// If the memory was requested at a particular address, use
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// os::attempt_reserve_memory_at() to avoid over mapping something
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// important. If available space is not detected, return NULL.
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if (requested_address != 0) {
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base = os::attempt_reserve_memory_at(size, requested_address);
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} else {
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base = os::reserve_memory(size, NULL, alignment);
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}
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if (base == NULL) return;
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// Check alignment constraints
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if (alignment > 0 && ((size_t)base & alignment - 1) != 0) {
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// Base not aligned, retry
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if (!os::release_memory(base, size)) fatal("os::release_memory failed");
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// Reserve size large enough to do manual alignment and
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// increase size to a multiple of the desired alignment
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size = align_size_up(size, alignment);
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size_t extra_size = size + alignment;
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char* extra_base = os::reserve_memory(extra_size, NULL, alignment);
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if (extra_base == NULL) return;
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// Do manual alignement
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base = (char*) align_size_up((uintptr_t) extra_base, alignment);
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assert(base >= extra_base, "just checking");
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// Release unused areas
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size_t unused_bottom_size = base - extra_base;
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size_t unused_top_size = extra_size - size - unused_bottom_size;
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assert(unused_bottom_size % os::vm_allocation_granularity() == 0,
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"size not allocation aligned");
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assert(unused_top_size % os::vm_allocation_granularity() == 0,
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"size not allocation aligned");
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if (unused_bottom_size > 0) {
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os::release_memory(extra_base, unused_bottom_size);
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}
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if (unused_top_size > 0) {
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os::release_memory(base + size, unused_top_size);
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}
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}
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}
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// Done
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_base = base;
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_size = size;
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_alignment = MAX2(alignment, (size_t) os::vm_page_size());
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assert(markOopDesc::encode_pointer_as_mark(_base)->decode_pointer() == _base,
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"area must be distinguisable from marks for mark-sweep");
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assert(markOopDesc::encode_pointer_as_mark(&_base[size])->decode_pointer() == &_base[size],
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"area must be distinguisable from marks for mark-sweep");
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}
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ReservedSpace::ReservedSpace(char* base, size_t size, size_t alignment,
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bool special) {
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assert((size % os::vm_allocation_granularity()) == 0,
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"size not allocation aligned");
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_base = base;
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_size = size;
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_alignment = alignment;
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_special = special;
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}
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ReservedSpace ReservedSpace::first_part(size_t partition_size, size_t alignment,
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bool split, bool realloc) {
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assert(partition_size <= size(), "partition failed");
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if (split) {
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os::split_reserved_memory(_base, _size, partition_size, realloc);
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}
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ReservedSpace result(base(), partition_size, alignment, special());
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return result;
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}
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ReservedSpace
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ReservedSpace::last_part(size_t partition_size, size_t alignment) {
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assert(partition_size <= size(), "partition failed");
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ReservedSpace result(base() + partition_size, size() - partition_size,
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alignment, special());
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return result;
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}
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size_t ReservedSpace::page_align_size_up(size_t size) {
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return align_size_up(size, os::vm_page_size());
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}
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size_t ReservedSpace::page_align_size_down(size_t size) {
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return align_size_down(size, os::vm_page_size());
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}
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size_t ReservedSpace::allocation_align_size_up(size_t size) {
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return align_size_up(size, os::vm_allocation_granularity());
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}
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size_t ReservedSpace::allocation_align_size_down(size_t size) {
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return align_size_down(size, os::vm_allocation_granularity());
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}
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void ReservedSpace::release() {
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if (is_reserved()) {
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if (special()) {
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os::release_memory_special(_base, _size);
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} else{
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os::release_memory(_base, _size);
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}
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_base = NULL;
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_size = 0;
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_special = false;
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}
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}
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// VirtualSpace
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VirtualSpace::VirtualSpace() {
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_low_boundary = NULL;
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_high_boundary = NULL;
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_low = NULL;
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_high = NULL;
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_lower_high = NULL;
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_middle_high = NULL;
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_upper_high = NULL;
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_lower_high_boundary = NULL;
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_middle_high_boundary = NULL;
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_upper_high_boundary = NULL;
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_lower_alignment = 0;
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_middle_alignment = 0;
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_upper_alignment = 0;
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}
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bool VirtualSpace::initialize(ReservedSpace rs, size_t committed_size) {
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if(!rs.is_reserved()) return false; // allocation failed.
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assert(_low_boundary == NULL, "VirtualSpace already initialized");
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_low_boundary = rs.base();
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_high_boundary = low_boundary() + rs.size();
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_low = low_boundary();
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_high = low();
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_special = rs.special();
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// When a VirtualSpace begins life at a large size, make all future expansion
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// and shrinking occur aligned to a granularity of large pages. This avoids
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// fragmentation of physical addresses that inhibits the use of large pages
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// by the OS virtual memory system. Empirically, we see that with a 4MB
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// page size, the only spaces that get handled this way are codecache and
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// the heap itself, both of which provide a substantial performance
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// boost in many benchmarks when covered by large pages.
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//
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// No attempt is made to force large page alignment at the very top and
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// bottom of the space if they are not aligned so already.
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_lower_alignment = os::vm_page_size();
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_middle_alignment = os::page_size_for_region(rs.size(), rs.size(), 1);
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_upper_alignment = os::vm_page_size();
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// End of each region
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_lower_high_boundary = (char*) round_to((intptr_t) low_boundary(), middle_alignment());
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_middle_high_boundary = (char*) round_down((intptr_t) high_boundary(), middle_alignment());
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_upper_high_boundary = high_boundary();
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// High address of each region
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_lower_high = low_boundary();
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_middle_high = lower_high_boundary();
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_upper_high = middle_high_boundary();
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// commit to initial size
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if (committed_size > 0) {
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if (!expand_by(committed_size)) {
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return false;
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}
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}
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return true;
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}
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VirtualSpace::~VirtualSpace() {
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release();
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}
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void VirtualSpace::release() {
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(void)os::release_memory(low_boundary(), reserved_size());
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|
406 |
_low_boundary = NULL;
|
|
407 |
_high_boundary = NULL;
|
|
408 |
_low = NULL;
|
|
409 |
_high = NULL;
|
|
410 |
_lower_high = NULL;
|
|
411 |
_middle_high = NULL;
|
|
412 |
_upper_high = NULL;
|
|
413 |
_lower_high_boundary = NULL;
|
|
414 |
_middle_high_boundary = NULL;
|
|
415 |
_upper_high_boundary = NULL;
|
|
416 |
_lower_alignment = 0;
|
|
417 |
_middle_alignment = 0;
|
|
418 |
_upper_alignment = 0;
|
|
419 |
_special = false;
|
|
420 |
}
|
|
421 |
|
|
422 |
|
|
423 |
size_t VirtualSpace::committed_size() const {
|
|
424 |
return pointer_delta(high(), low(), sizeof(char));
|
|
425 |
}
|
|
426 |
|
|
427 |
|
|
428 |
size_t VirtualSpace::reserved_size() const {
|
|
429 |
return pointer_delta(high_boundary(), low_boundary(), sizeof(char));
|
|
430 |
}
|
|
431 |
|
|
432 |
|
|
433 |
size_t VirtualSpace::uncommitted_size() const {
|
|
434 |
return reserved_size() - committed_size();
|
|
435 |
}
|
|
436 |
|
|
437 |
|
|
438 |
bool VirtualSpace::contains(const void* p) const {
|
|
439 |
return low() <= (const char*) p && (const char*) p < high();
|
|
440 |
}
|
|
441 |
|
|
442 |
/*
|
|
443 |
First we need to determine if a particular virtual space is using large
|
|
444 |
pages. This is done at the initialize function and only virtual spaces
|
|
445 |
that are larger than LargePageSizeInBytes use large pages. Once we
|
|
446 |
have determined this, all expand_by and shrink_by calls must grow and
|
|
447 |
shrink by large page size chunks. If a particular request
|
|
448 |
is within the current large page, the call to commit and uncommit memory
|
|
449 |
can be ignored. In the case that the low and high boundaries of this
|
|
450 |
space is not large page aligned, the pages leading to the first large
|
|
451 |
page address and the pages after the last large page address must be
|
|
452 |
allocated with default pages.
|
|
453 |
*/
|
|
454 |
bool VirtualSpace::expand_by(size_t bytes, bool pre_touch) {
|
|
455 |
if (uncommitted_size() < bytes) return false;
|
|
456 |
|
|
457 |
if (special()) {
|
|
458 |
// don't commit memory if the entire space is pinned in memory
|
|
459 |
_high += bytes;
|
|
460 |
return true;
|
|
461 |
}
|
|
462 |
|
|
463 |
char* previous_high = high();
|
|
464 |
char* unaligned_new_high = high() + bytes;
|
|
465 |
assert(unaligned_new_high <= high_boundary(),
|
|
466 |
"cannot expand by more than upper boundary");
|
|
467 |
|
|
468 |
// Calculate where the new high for each of the regions should be. If
|
|
469 |
// the low_boundary() and high_boundary() are LargePageSizeInBytes aligned
|
|
470 |
// then the unaligned lower and upper new highs would be the
|
|
471 |
// lower_high() and upper_high() respectively.
|
|
472 |
char* unaligned_lower_new_high =
|
|
473 |
MIN2(unaligned_new_high, lower_high_boundary());
|
|
474 |
char* unaligned_middle_new_high =
|
|
475 |
MIN2(unaligned_new_high, middle_high_boundary());
|
|
476 |
char* unaligned_upper_new_high =
|
|
477 |
MIN2(unaligned_new_high, upper_high_boundary());
|
|
478 |
|
|
479 |
// Align the new highs based on the regions alignment. lower and upper
|
|
480 |
// alignment will always be default page size. middle alignment will be
|
|
481 |
// LargePageSizeInBytes if the actual size of the virtual space is in
|
|
482 |
// fact larger than LargePageSizeInBytes.
|
|
483 |
char* aligned_lower_new_high =
|
|
484 |
(char*) round_to((intptr_t) unaligned_lower_new_high, lower_alignment());
|
|
485 |
char* aligned_middle_new_high =
|
|
486 |
(char*) round_to((intptr_t) unaligned_middle_new_high, middle_alignment());
|
|
487 |
char* aligned_upper_new_high =
|
|
488 |
(char*) round_to((intptr_t) unaligned_upper_new_high, upper_alignment());
|
|
489 |
|
|
490 |
// Determine which regions need to grow in this expand_by call.
|
|
491 |
// If you are growing in the lower region, high() must be in that
|
|
492 |
// region so calcuate the size based on high(). For the middle and
|
|
493 |
// upper regions, determine the starting point of growth based on the
|
|
494 |
// location of high(). By getting the MAX of the region's low address
|
|
495 |
// (or the prevoius region's high address) and high(), we can tell if it
|
|
496 |
// is an intra or inter region growth.
|
|
497 |
size_t lower_needs = 0;
|
|
498 |
if (aligned_lower_new_high > lower_high()) {
|
|
499 |
lower_needs =
|
|
500 |
pointer_delta(aligned_lower_new_high, lower_high(), sizeof(char));
|
|
501 |
}
|
|
502 |
size_t middle_needs = 0;
|
|
503 |
if (aligned_middle_new_high > middle_high()) {
|
|
504 |
middle_needs =
|
|
505 |
pointer_delta(aligned_middle_new_high, middle_high(), sizeof(char));
|
|
506 |
}
|
|
507 |
size_t upper_needs = 0;
|
|
508 |
if (aligned_upper_new_high > upper_high()) {
|
|
509 |
upper_needs =
|
|
510 |
pointer_delta(aligned_upper_new_high, upper_high(), sizeof(char));
|
|
511 |
}
|
|
512 |
|
|
513 |
// Check contiguity.
|
|
514 |
assert(low_boundary() <= lower_high() &&
|
|
515 |
lower_high() <= lower_high_boundary(),
|
|
516 |
"high address must be contained within the region");
|
|
517 |
assert(lower_high_boundary() <= middle_high() &&
|
|
518 |
middle_high() <= middle_high_boundary(),
|
|
519 |
"high address must be contained within the region");
|
|
520 |
assert(middle_high_boundary() <= upper_high() &&
|
|
521 |
upper_high() <= upper_high_boundary(),
|
|
522 |
"high address must be contained within the region");
|
|
523 |
|
|
524 |
// Commit regions
|
|
525 |
if (lower_needs > 0) {
|
|
526 |
assert(low_boundary() <= lower_high() &&
|
|
527 |
lower_high() + lower_needs <= lower_high_boundary(),
|
|
528 |
"must not expand beyond region");
|
|
529 |
if (!os::commit_memory(lower_high(), lower_needs)) {
|
|
530 |
debug_only(warning("os::commit_memory failed"));
|
|
531 |
return false;
|
|
532 |
} else {
|
|
533 |
_lower_high += lower_needs;
|
|
534 |
}
|
|
535 |
}
|
|
536 |
if (middle_needs > 0) {
|
|
537 |
assert(lower_high_boundary() <= middle_high() &&
|
|
538 |
middle_high() + middle_needs <= middle_high_boundary(),
|
|
539 |
"must not expand beyond region");
|
|
540 |
if (!os::commit_memory(middle_high(), middle_needs, middle_alignment())) {
|
|
541 |
debug_only(warning("os::commit_memory failed"));
|
|
542 |
return false;
|
|
543 |
}
|
|
544 |
_middle_high += middle_needs;
|
|
545 |
}
|
|
546 |
if (upper_needs > 0) {
|
|
547 |
assert(middle_high_boundary() <= upper_high() &&
|
|
548 |
upper_high() + upper_needs <= upper_high_boundary(),
|
|
549 |
"must not expand beyond region");
|
|
550 |
if (!os::commit_memory(upper_high(), upper_needs)) {
|
|
551 |
debug_only(warning("os::commit_memory failed"));
|
|
552 |
return false;
|
|
553 |
} else {
|
|
554 |
_upper_high += upper_needs;
|
|
555 |
}
|
|
556 |
}
|
|
557 |
|
|
558 |
if (pre_touch || AlwaysPreTouch) {
|
|
559 |
int vm_ps = os::vm_page_size();
|
|
560 |
for (char* curr = previous_high;
|
|
561 |
curr < unaligned_new_high;
|
|
562 |
curr += vm_ps) {
|
|
563 |
// Note the use of a write here; originally we tried just a read, but
|
|
564 |
// since the value read was unused, the optimizer removed the read.
|
|
565 |
// If we ever have a concurrent touchahead thread, we'll want to use
|
|
566 |
// a read, to avoid the potential of overwriting data (if a mutator
|
|
567 |
// thread beats the touchahead thread to a page). There are various
|
|
568 |
// ways of making sure this read is not optimized away: for example,
|
|
569 |
// generating the code for a read procedure at runtime.
|
|
570 |
*curr = 0;
|
|
571 |
}
|
|
572 |
}
|
|
573 |
|
|
574 |
_high += bytes;
|
|
575 |
return true;
|
|
576 |
}
|
|
577 |
|
|
578 |
// A page is uncommitted if the contents of the entire page is deemed unusable.
|
|
579 |
// Continue to decrement the high() pointer until it reaches a page boundary
|
|
580 |
// in which case that particular page can now be uncommitted.
|
|
581 |
void VirtualSpace::shrink_by(size_t size) {
|
|
582 |
if (committed_size() < size)
|
|
583 |
fatal("Cannot shrink virtual space to negative size");
|
|
584 |
|
|
585 |
if (special()) {
|
|
586 |
// don't uncommit if the entire space is pinned in memory
|
|
587 |
_high -= size;
|
|
588 |
return;
|
|
589 |
}
|
|
590 |
|
|
591 |
char* unaligned_new_high = high() - size;
|
|
592 |
assert(unaligned_new_high >= low_boundary(), "cannot shrink past lower boundary");
|
|
593 |
|
|
594 |
// Calculate new unaligned address
|
|
595 |
char* unaligned_upper_new_high =
|
|
596 |
MAX2(unaligned_new_high, middle_high_boundary());
|
|
597 |
char* unaligned_middle_new_high =
|
|
598 |
MAX2(unaligned_new_high, lower_high_boundary());
|
|
599 |
char* unaligned_lower_new_high =
|
|
600 |
MAX2(unaligned_new_high, low_boundary());
|
|
601 |
|
|
602 |
// Align address to region's alignment
|
|
603 |
char* aligned_upper_new_high =
|
|
604 |
(char*) round_to((intptr_t) unaligned_upper_new_high, upper_alignment());
|
|
605 |
char* aligned_middle_new_high =
|
|
606 |
(char*) round_to((intptr_t) unaligned_middle_new_high, middle_alignment());
|
|
607 |
char* aligned_lower_new_high =
|
|
608 |
(char*) round_to((intptr_t) unaligned_lower_new_high, lower_alignment());
|
|
609 |
|
|
610 |
// Determine which regions need to shrink
|
|
611 |
size_t upper_needs = 0;
|
|
612 |
if (aligned_upper_new_high < upper_high()) {
|
|
613 |
upper_needs =
|
|
614 |
pointer_delta(upper_high(), aligned_upper_new_high, sizeof(char));
|
|
615 |
}
|
|
616 |
size_t middle_needs = 0;
|
|
617 |
if (aligned_middle_new_high < middle_high()) {
|
|
618 |
middle_needs =
|
|
619 |
pointer_delta(middle_high(), aligned_middle_new_high, sizeof(char));
|
|
620 |
}
|
|
621 |
size_t lower_needs = 0;
|
|
622 |
if (aligned_lower_new_high < lower_high()) {
|
|
623 |
lower_needs =
|
|
624 |
pointer_delta(lower_high(), aligned_lower_new_high, sizeof(char));
|
|
625 |
}
|
|
626 |
|
|
627 |
// Check contiguity.
|
|
628 |
assert(middle_high_boundary() <= upper_high() &&
|
|
629 |
upper_high() <= upper_high_boundary(),
|
|
630 |
"high address must be contained within the region");
|
|
631 |
assert(lower_high_boundary() <= middle_high() &&
|
|
632 |
middle_high() <= middle_high_boundary(),
|
|
633 |
"high address must be contained within the region");
|
|
634 |
assert(low_boundary() <= lower_high() &&
|
|
635 |
lower_high() <= lower_high_boundary(),
|
|
636 |
"high address must be contained within the region");
|
|
637 |
|
|
638 |
// Uncommit
|
|
639 |
if (upper_needs > 0) {
|
|
640 |
assert(middle_high_boundary() <= aligned_upper_new_high &&
|
|
641 |
aligned_upper_new_high + upper_needs <= upper_high_boundary(),
|
|
642 |
"must not shrink beyond region");
|
|
643 |
if (!os::uncommit_memory(aligned_upper_new_high, upper_needs)) {
|
|
644 |
debug_only(warning("os::uncommit_memory failed"));
|
|
645 |
return;
|
|
646 |
} else {
|
|
647 |
_upper_high -= upper_needs;
|
|
648 |
}
|
|
649 |
}
|
|
650 |
if (middle_needs > 0) {
|
|
651 |
assert(lower_high_boundary() <= aligned_middle_new_high &&
|
|
652 |
aligned_middle_new_high + middle_needs <= middle_high_boundary(),
|
|
653 |
"must not shrink beyond region");
|
|
654 |
if (!os::uncommit_memory(aligned_middle_new_high, middle_needs)) {
|
|
655 |
debug_only(warning("os::uncommit_memory failed"));
|
|
656 |
return;
|
|
657 |
} else {
|
|
658 |
_middle_high -= middle_needs;
|
|
659 |
}
|
|
660 |
}
|
|
661 |
if (lower_needs > 0) {
|
|
662 |
assert(low_boundary() <= aligned_lower_new_high &&
|
|
663 |
aligned_lower_new_high + lower_needs <= lower_high_boundary(),
|
|
664 |
"must not shrink beyond region");
|
|
665 |
if (!os::uncommit_memory(aligned_lower_new_high, lower_needs)) {
|
|
666 |
debug_only(warning("os::uncommit_memory failed"));
|
|
667 |
return;
|
|
668 |
} else {
|
|
669 |
_lower_high -= lower_needs;
|
|
670 |
}
|
|
671 |
}
|
|
672 |
|
|
673 |
_high -= size;
|
|
674 |
}
|
|
675 |
|
|
676 |
#ifndef PRODUCT
|
|
677 |
void VirtualSpace::check_for_contiguity() {
|
|
678 |
// Check contiguity.
|
|
679 |
assert(low_boundary() <= lower_high() &&
|
|
680 |
lower_high() <= lower_high_boundary(),
|
|
681 |
"high address must be contained within the region");
|
|
682 |
assert(lower_high_boundary() <= middle_high() &&
|
|
683 |
middle_high() <= middle_high_boundary(),
|
|
684 |
"high address must be contained within the region");
|
|
685 |
assert(middle_high_boundary() <= upper_high() &&
|
|
686 |
upper_high() <= upper_high_boundary(),
|
|
687 |
"high address must be contained within the region");
|
|
688 |
assert(low() >= low_boundary(), "low");
|
|
689 |
assert(low_boundary() <= lower_high_boundary(), "lower high boundary");
|
|
690 |
assert(upper_high_boundary() <= high_boundary(), "upper high boundary");
|
|
691 |
assert(high() <= upper_high(), "upper high");
|
|
692 |
}
|
|
693 |
|
|
694 |
void VirtualSpace::print() {
|
|
695 |
tty->print ("Virtual space:");
|
|
696 |
if (special()) tty->print(" (pinned in memory)");
|
|
697 |
tty->cr();
|
|
698 |
tty->print_cr(" - committed: %ld", committed_size());
|
|
699 |
tty->print_cr(" - reserved: %ld", reserved_size());
|
|
700 |
tty->print_cr(" - [low, high]: [" INTPTR_FORMAT ", " INTPTR_FORMAT "]", low(), high());
|
|
701 |
tty->print_cr(" - [low_b, high_b]: [" INTPTR_FORMAT ", " INTPTR_FORMAT "]", low_boundary(), high_boundary());
|
|
702 |
}
|
|
703 |
|
|
704 |
#endif
|