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src/hotspot/share/memory/virtualspace.cpp
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*** 1,7 ****
/*
! * Copyright (c) 1997, 2016, 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.
--- 1,7 ----
/*
! * Copyright (c) 1997, 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.
*** 33,46 ****
// ReservedSpace
// Dummy constructor
ReservedSpace::ReservedSpace() : _base(NULL), _size(0), _noaccess_prefix(0),
! _alignment(0), _special(false), _executable(false) {
}
! ReservedSpace::ReservedSpace(size_t size, size_t preferred_page_size) {
bool has_preferred_page_size = preferred_page_size != 0;
// Want to use large pages where possible and pad with small pages.
size_t page_size = has_preferred_page_size ? preferred_page_size : os::page_size_for_region_unaligned(size, 1);
bool large_pages = page_size != (size_t)os::vm_page_size();
size_t alignment;
--- 33,46 ----
// ReservedSpace
// Dummy constructor
ReservedSpace::ReservedSpace() : _base(NULL), _size(0), _noaccess_prefix(0),
! _alignment(0), _special(false), _executable(false), _fd_for_heap(-1) {
}
! ReservedSpace::ReservedSpace(size_t size, size_t preferred_page_size) : _fd_for_heap(-1) {
bool has_preferred_page_size = preferred_page_size != 0;
// Want to use large pages where possible and pad with small pages.
size_t page_size = has_preferred_page_size ? preferred_page_size : os::page_size_for_region_unaligned(size, 1);
bool large_pages = page_size != (size_t)os::vm_page_size();
size_t alignment;
*** 57,79 ****
initialize(size, alignment, large_pages, NULL, false);
}
ReservedSpace::ReservedSpace(size_t size, size_t alignment,
bool large,
! char* requested_address) {
initialize(size, alignment, large, requested_address, false);
}
ReservedSpace::ReservedSpace(size_t size, size_t alignment,
bool large,
! bool executable) {
initialize(size, alignment, large, NULL, executable);
}
// Helper method.
static bool failed_to_reserve_as_requested(char* base, char* requested_address,
! const size_t size, bool special)
{
if (base == requested_address || requested_address == NULL)
return false; // did not fail
if (base != NULL) {
--- 57,90 ----
initialize(size, alignment, large_pages, NULL, false);
}
ReservedSpace::ReservedSpace(size_t size, size_t alignment,
bool large,
! char* requested_address) : _fd_for_heap(-1) {
initialize(size, alignment, large, requested_address, false);
}
ReservedSpace::ReservedSpace(size_t size, size_t alignment,
bool large,
! bool executable) : _fd_for_heap(-1) {
initialize(size, alignment, large, NULL, executable);
}
+ // Helper method
+ static void unmap_or_release_memory(char* base, size_t size, bool is_file_mapped) {
+ if (is_file_mapped) {
+ if (!os::unmap_memory(base, size)) {
+ fatal("os::unmap_memory failed");
+ }
+ } else if (!os::release_memory(base, size)) {
+ fatal("os::release_memory failed");
+ }
+ }
+
// Helper method.
static bool failed_to_reserve_as_requested(char* base, char* requested_address,
! const size_t size, bool special, bool is_file_mapped = false)
{
if (base == requested_address || requested_address == NULL)
return false; // did not fail
if (base != NULL) {
*** 85,97 ****
if (special) {
if (!os::release_memory_special(base, size)) {
fatal("os::release_memory_special failed");
}
} else {
! if (!os::release_memory(base, size)) {
! fatal("os::release_memory failed");
! }
}
}
return true;
}
--- 96,106 ----
if (special) {
if (!os::release_memory_special(base, size)) {
fatal("os::release_memory_special failed");
}
} else {
! unmap_or_release_memory(base, size, is_file_mapped);
}
}
return true;
}
*** 118,128 ****
--- 127,148 ----
return;
}
// If OS doesn't support demand paging for large page memory, we need
// to use reserve_memory_special() to reserve and pin the entire region.
+ // If there is a backing file directory for this space then whether
+ // large pages are allocated is up to the filesystem of the backing file.
+ // So we ignore the UseLargePages flag in this case.
bool special = large && !os::can_commit_large_page_memory();
+ if (special && _fd_for_heap != -1) {
+ special = false;
+ if (UseLargePages && (!FLAG_IS_DEFAULT(UseLargePages) ||
+ !FLAG_IS_DEFAULT(LargePageSizeInBytes))) {
+ log_debug(gc, heap)("Ignoring UseLargePages since large page support is up to the file system of the backing file for Java heap");
+ }
+ }
+
char* base = NULL;
if (special) {
base = os::reserve_memory_special(size, alignment, requested_address, executable);
*** 155,185 ****
// If the memory was requested at a particular address, use
// os::attempt_reserve_memory_at() to avoid over mapping something
// important. If available space is not detected, return NULL.
if (requested_address != 0) {
! base = os::attempt_reserve_memory_at(size, requested_address);
! if (failed_to_reserve_as_requested(base, requested_address, size, false)) {
// OS ignored requested address. Try different address.
base = NULL;
}
} else {
! base = os::reserve_memory(size, NULL, alignment);
}
if (base == NULL) return;
// Check alignment constraints
if ((((size_t)base) & (alignment - 1)) != 0) {
// Base not aligned, retry
! if (!os::release_memory(base, size)) fatal("os::release_memory failed");
// Make sure that size is aligned
size = align_up(size, alignment);
! base = os::reserve_memory_aligned(size, alignment);
if (requested_address != 0 &&
! failed_to_reserve_as_requested(base, requested_address, size, false)) {
// As a result of the alignment constraints, the allocated base differs
// from the requested address. Return back to the caller who can
// take remedial action (like try again without a requested address).
assert(_base == NULL, "should be");
return;
--- 175,206 ----
// If the memory was requested at a particular address, use
// os::attempt_reserve_memory_at() to avoid over mapping something
// important. If available space is not detected, return NULL.
if (requested_address != 0) {
! base = os::attempt_reserve_memory_at(size, requested_address, _fd_for_heap);
! if (failed_to_reserve_as_requested(base, requested_address, size, false, _fd_for_heap != -1)) {
// OS ignored requested address. Try different address.
base = NULL;
}
} else {
! base = os::reserve_memory(size, NULL, alignment, _fd_for_heap);
}
if (base == NULL) return;
// Check alignment constraints
if ((((size_t)base) & (alignment - 1)) != 0) {
// Base not aligned, retry
! unmap_or_release_memory(base, size, _fd_for_heap != -1 /*is_file_mapped*/);
!
// Make sure that size is aligned
size = align_up(size, alignment);
! base = os::reserve_memory_aligned(size, alignment, _fd_for_heap);
if (requested_address != 0 &&
! failed_to_reserve_as_requested(base, requested_address, size, false, _fd_for_heap != -1)) {
// As a result of the alignment constraints, the allocated base differs
// from the requested address. Return back to the caller who can
// take remedial action (like try again without a requested address).
assert(_base == NULL, "should be");
return;
*** 188,197 ****
--- 209,222 ----
}
// Done
_base = base;
_size = size;
_alignment = alignment;
+ // If heap is reserved with a backing file, the entire space has been committed. So set the _special flag to true
+ if (_fd_for_heap != -1) {
+ _special = true;
+ }
}
ReservedSpace::ReservedSpace(char* base, size_t size, size_t alignment,
bool special, bool executable) {
*** 250,260 ****
--- 275,289 ----
void ReservedSpace::release() {
if (is_reserved()) {
char *real_base = _base - _noaccess_prefix;
const size_t real_size = _size + _noaccess_prefix;
if (special()) {
+ if (_fd_for_heap != -1) {
+ os::unmap_memory(real_base, real_size);
+ } else {
os::release_memory_special(real_base, real_size);
+ }
} else{
os::release_memory(real_base, real_size);
}
_base = NULL;
_size = 0;
*** 311,321 ****
--- 340,360 ----
release();
}
// If OS doesn't support demand paging for large page memory, we need
// to use reserve_memory_special() to reserve and pin the entire region.
+ // If there is a backing file directory for this space then whether
+ // large pages are allocated is up to the filesystem of the backing file.
+ // So we ignore the UseLargePages flag in this case.
bool special = large && !os::can_commit_large_page_memory();
+ if (special && _fd_for_heap != -1) {
+ special = false;
+ if (UseLargePages && (!FLAG_IS_DEFAULT(UseLargePages) ||
+ !FLAG_IS_DEFAULT(LargePageSizeInBytes))) {
+ log_debug(gc, heap)("Cannot allocate large pages for Java Heap when AllocateHeapAt option is set.");
+ }
+ }
char* base = NULL;
log_trace(gc, heap, coops)("Trying to allocate at address " PTR_FORMAT
" heap of size " SIZE_FORMAT_HEX,
p2i(requested_address),
*** 348,369 ****
// If the memory was requested at a particular address, use
// os::attempt_reserve_memory_at() to avoid over mapping something
// important. If available space is not detected, return NULL.
if (requested_address != 0) {
! base = os::attempt_reserve_memory_at(size, requested_address);
} else {
! base = os::reserve_memory(size, NULL, alignment);
}
}
if (base == NULL) { return; }
// Done
_base = base;
_size = size;
_alignment = alignment;
// Check alignment constraints
if ((((size_t)base) & (alignment - 1)) != 0) {
// Base not aligned, retry.
release();
}
--- 387,413 ----
// If the memory was requested at a particular address, use
// os::attempt_reserve_memory_at() to avoid over mapping something
// important. If available space is not detected, return NULL.
if (requested_address != 0) {
! base = os::attempt_reserve_memory_at(size, requested_address, _fd_for_heap);
} else {
! base = os::reserve_memory(size, NULL, alignment, _fd_for_heap);
}
}
if (base == NULL) { return; }
// Done
_base = base;
_size = size;
_alignment = alignment;
+ // If heap is reserved with a backing file, the entire space has been committed. So set the _special flag to true
+ if (_fd_for_heap != -1) {
+ _special = true;
+ }
+
// Check alignment constraints
if ((((size_t)base) & (alignment - 1)) != 0) {
// Base not aligned, retry.
release();
}
*** 554,569 ****
initialize(size + noaccess_prefix, alignment, large, NULL, false);
}
}
}
! ReservedHeapSpace::ReservedHeapSpace(size_t size, size_t alignment, bool large) : ReservedSpace() {
if (size == 0) {
return;
}
// Heap size should be aligned to alignment, too.
guarantee(is_aligned(size, alignment), "set by caller");
if (UseCompressedOops) {
initialize_compressed_heap(size, alignment, large);
--- 598,621 ----
initialize(size + noaccess_prefix, alignment, large, NULL, false);
}
}
}
! ReservedHeapSpace::ReservedHeapSpace(size_t size, size_t alignment, bool large, const char* heap_allocation_directory) : ReservedSpace() {
if (size == 0) {
return;
}
+ if (heap_allocation_directory != NULL) {
+ _fd_for_heap = os::create_file_for_heap(heap_allocation_directory);
+ if (_fd_for_heap == -1) {
+ vm_exit_during_initialization(
+ err_msg("Could not create file for Heap at location %s", heap_allocation_directory));
+ }
+ }
+
// Heap size should be aligned to alignment, too.
guarantee(is_aligned(size, alignment), "set by caller");
if (UseCompressedOops) {
initialize_compressed_heap(size, alignment, large);
*** 583,592 ****
--- 635,648 ----
"area must be distinguishable from marks for mark-sweep");
if (base() != NULL) {
MemTracker::record_virtual_memory_type((address)base(), mtJavaHeap);
}
+
+ if (_fd_for_heap != -1) {
+ os::close(_fd_for_heap);
+ }
}
// Reserve space for code segment. Same as Java heap only we mark this as
// executable.
ReservedCodeSpace::ReservedCodeSpace(size_t r_size,
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