1 /*
2 * Copyright (c) 1997, 2018, Oracle 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 "precompiled.hpp"
26 #include "logging/log.hpp"
27 #include "memory/resourceArea.hpp"
28 #include "memory/virtualspace.hpp"
29 #include "oops/markOop.hpp"
30 #include "oops/oop.inline.hpp"
31 #include "runtime/os.inline.hpp"
32 #include "services/memTracker.hpp"
33 #include "utilities/align.hpp"
34
35 // ReservedSpace
36
37 // Dummy constructor
38 ReservedSpace::ReservedSpace() : _base(NULL), _size(0), _noaccess_prefix(0),
39 _alignment(0), _special(false), _fd_for_heap(-1), _actual_page_size(0), _executable(false) {
40 }
41
42 ReservedSpace::ReservedSpace(size_t size, size_t preferred_page_size) : _fd_for_heap(-1), _actual_page_size(0) {
43 bool has_preferred_page_size = preferred_page_size != 0;
44 // Want to use large pages where possible and pad with small pages.
45 size_t page_size = has_preferred_page_size ? preferred_page_size : os::page_size_for_region_unaligned(size, 1);
46 bool large_pages = page_size != (size_t)os::vm_page_size();
47 size_t alignment;
48 if (large_pages && has_preferred_page_size) {
49 alignment = MAX2(page_size, (size_t)os::vm_allocation_granularity());
50 // ReservedSpace initialization requires size to be aligned to the given
51 // alignment. Align the size up.
52 size = align_up(size, alignment);
53 } else {
54 // Don't force the alignment to be large page aligned,
55 // since that will waste memory.
56 alignment = os::vm_allocation_granularity();
57 }
58 initialize(size, alignment, large_pages, NULL, false);
59 }
60
61 ReservedSpace::ReservedSpace(size_t size, size_t alignment,
62 bool large,
63 char* requested_address) : _fd_for_heap(-1), _actual_page_size(0) {
64 initialize(size, alignment, large, requested_address, false);
65 }
66
67 ReservedSpace::ReservedSpace(size_t size, size_t alignment,
68 bool large,
69 bool executable) : _fd_for_heap(-1), _actual_page_size(0) {
70 initialize(size, alignment, large, NULL, executable);
71 }
72
73 ReservedSpace::ReservedSpace(char* base, size_t size, size_t alignment,
74 bool special, bool executable) : _fd_for_heap(-1), _actual_page_size(0) {
75 assert((size % os::vm_allocation_granularity()) == 0,
76 "size not allocation aligned");
77 _base = base;
78 _size = size;
79 _alignment = alignment;
80 _noaccess_prefix = 0;
81 _special = special;
82 _executable = executable;
83 }
84
85 // Helper method
86 static void unmap_or_release_memory(char* base, size_t size, bool is_file_mapped) {
87 if (is_file_mapped) {
88 if (!os::unmap_memory(base, size)) {
89 fatal("os::unmap_memory failed");
90 }
91 } else if (!os::release_memory(base, size)) {
92 fatal("os::release_memory failed");
93 }
94 }
95
96 // Helper method.
97 static bool failed_to_reserve_as_requested(char* base, char* requested_address,
98 const size_t size, bool special, bool is_file_mapped = false)
99 {
100 if (base == requested_address || requested_address == NULL)
101 return false; // did not fail
102
103 if (base != NULL) {
104 // Different reserve address may be acceptable in other cases
105 // but for compressed oops heap should be at requested address.
106 assert(UseCompressedOops, "currently requested address used only for compressed oops");
107 log_debug(gc, heap, coops)("Reserved memory not at requested address: " PTR_FORMAT " vs " PTR_FORMAT, p2i(base), p2i(requested_address));
108 // OS ignored requested address. Try different address.
109 if (special) {
110 if (!os::release_memory_special(base, size)) {
111 fatal("os::release_memory_special failed");
112 }
113 } else {
114 unmap_or_release_memory(base, size, is_file_mapped);
115 }
116 }
117 return true;
118 }
119
120 // Should be called after _special is decided.
121 void ReservedSpace::update_actual_page_size(bool large_page) {
122 // There are two ways to manage large page memory in ReservedSpace.
123 // 1. OS supports committing large page memory.
124 // 2. OS doesn't support committing large page memory so ReservedSpace manages it specially.
125 // When succeeded reserving it, '_special' will be set.
126 if (large_page && (os::can_commit_large_page_memory() || _special)) {
127 _actual_page_size = os::large_page_size();
128 } else {
129 _actual_page_size = os::vm_page_size();
130 }
131 }
132
133 void ReservedSpace::initialize(size_t size, size_t alignment, bool large,
134 char* requested_address,
135 bool executable) {
136 const size_t granularity = os::vm_allocation_granularity();
137 assert((size & (granularity - 1)) == 0,
138 "size not aligned to os::vm_allocation_granularity()");
139 assert((alignment & (granularity - 1)) == 0,
140 "alignment not aligned to os::vm_allocation_granularity()");
141 assert(alignment == 0 || is_power_of_2((intptr_t)alignment),
142 "not a power of 2");
143
144 alignment = MAX2(alignment, (size_t)os::vm_page_size());
145
146 _base = NULL;
147 _size = 0;
148 _special = false;
149 _executable = executable;
150 _alignment = 0;
151 _noaccess_prefix = 0;
152 if (size == 0) {
153 return;
154 }
155
156 // If OS doesn't support demand paging for large page memory, we need
157 // to use reserve_memory_special() to reserve and pin the entire region.
158 // If there is a backing file directory for this space then whether
159 // large pages are allocated is up to the filesystem of the backing file.
160 // So we ignore the UseLargePages flag in this case.
161 bool special = large && !os::can_commit_large_page_memory();
162 if (special && _fd_for_heap != -1) {
163 special = false;
164 if (UseLargePages && (!FLAG_IS_DEFAULT(UseLargePages) ||
165 !FLAG_IS_DEFAULT(LargePageSizeInBytes))) {
166 log_debug(gc, heap)("Ignoring UseLargePages since large page support is up to the file system of the backing file for Java heap");
167 }
168 }
169
170 char* base = NULL;
171
172 if (special) {
173
174 base = os::reserve_memory_special(size, alignment, requested_address, executable);
175
176 if (base != NULL) {
177 if (failed_to_reserve_as_requested(base, requested_address, size, true)) {
178 // OS ignored requested address. Try different address.
179 return;
180 }
181 // Check alignment constraints.
182 assert((uintptr_t) base % alignment == 0,
183 "Large pages returned a non-aligned address, base: "
184 PTR_FORMAT " alignment: " SIZE_FORMAT_HEX,
185 p2i(base), alignment);
186 _special = true;
187 } else {
188 // failed; try to reserve regular memory below
189 if (UseLargePages && (!FLAG_IS_DEFAULT(UseLargePages) ||
190 !FLAG_IS_DEFAULT(LargePageSizeInBytes))) {
191 log_debug(gc, heap, coops)("Reserve regular memory without large pages");
192 }
193 }
194 }
195
196 if (base == NULL) {
197 // Optimistically assume that the OSes returns an aligned base pointer.
198 // When reserving a large address range, most OSes seem to align to at
199 // least 64K.
200
201 // If the memory was requested at a particular address, use
202 // os::attempt_reserve_memory_at() to avoid over mapping something
203 // important. If available space is not detected, return NULL.
204
205 if (requested_address != 0) {
206 base = os::attempt_reserve_memory_at(size, requested_address, _fd_for_heap);
207 if (failed_to_reserve_as_requested(base, requested_address, size, false, _fd_for_heap != -1)) {
208 // OS ignored requested address. Try different address.
209 base = NULL;
210 }
211 } else {
212 base = os::reserve_memory(size, NULL, alignment, _fd_for_heap);
213 }
214
215 if (base == NULL) return;
216
217 // Check alignment constraints
218 if ((((size_t)base) & (alignment - 1)) != 0) {
219 // Base not aligned, retry
220 unmap_or_release_memory(base, size, _fd_for_heap != -1 /*is_file_mapped*/);
221
222 // Make sure that size is aligned
223 size = align_up(size, alignment);
224 base = os::reserve_memory_aligned(size, alignment, _fd_for_heap);
225
226 if (requested_address != 0 &&
227 failed_to_reserve_as_requested(base, requested_address, size, false, _fd_for_heap != -1)) {
228 // As a result of the alignment constraints, the allocated base differs
229 // from the requested address. Return back to the caller who can
230 // take remedial action (like try again without a requested address).
231 assert(_base == NULL, "should be");
232 return;
233 }
234 }
235 }
236 // Done
237 _base = base;
238 _size = size;
239 _alignment = alignment;
240 // If heap is reserved with a backing file, the entire space has been committed. So set the _special flag to true
241 if (_fd_for_heap != -1) {
242 _special = true;
243 }
244
245 update_actual_page_size(large);
246 }
247
248 ReservedSpace ReservedSpace::first_part(size_t partition_size, size_t alignment,
249 bool split, bool realloc) {
250 assert(partition_size <= size(), "partition failed");
251 if (split) {
252 os::split_reserved_memory(base(), size(), partition_size, realloc);
253 }
254 ReservedSpace result(base(), partition_size, alignment, special(),
255 executable());
256 return result;
257 }
258
259
260 ReservedSpace
261 ReservedSpace::last_part(size_t partition_size, size_t alignment) {
262 assert(partition_size <= size(), "partition failed");
263 ReservedSpace result(base() + partition_size, size() - partition_size,
264 alignment, special(), executable());
265 return result;
266 }
267
268
269 size_t ReservedSpace::page_align_size_up(size_t size) {
270 return align_up(size, os::vm_page_size());
271 }
272
273
274 size_t ReservedSpace::page_align_size_down(size_t size) {
275 return align_down(size, os::vm_page_size());
276 }
277
278
279 size_t ReservedSpace::allocation_align_size_up(size_t size) {
280 return align_up(size, os::vm_allocation_granularity());
281 }
282
283
284 size_t ReservedSpace::allocation_align_size_down(size_t size) {
285 return align_down(size, os::vm_allocation_granularity());
286 }
287
288
289 void ReservedSpace::release() {
290 if (is_reserved()) {
291 char *real_base = _base - _noaccess_prefix;
292 const size_t real_size = _size + _noaccess_prefix;
293 if (special()) {
294 if (_fd_for_heap != -1) {
295 os::unmap_memory(real_base, real_size);
296 } else {
297 os::release_memory_special(real_base, real_size);
298 }
299 } else{
300 os::release_memory(real_base, real_size);
301 }
302 _base = NULL;
303 _size = 0;
304 _noaccess_prefix = 0;
305 _alignment = 0;
306 _special = false;
307 _executable = false;
308 _actual_page_size = 0;
309 }
310 }
311
312 static size_t noaccess_prefix_size(size_t alignment) {
313 return lcm(os::vm_page_size(), alignment);
314 }
315
316 void ReservedHeapSpace::establish_noaccess_prefix() {
317 assert(_alignment >= (size_t)os::vm_page_size(), "must be at least page size big");
318 _noaccess_prefix = noaccess_prefix_size(_alignment);
319
320 if (base() && base() + _size > (char *)OopEncodingHeapMax) {
321 if (true
322 WIN64_ONLY(&& !UseLargePages)
323 AIX_ONLY(&& os::vm_page_size() != 64*K)) {
324 // Protect memory at the base of the allocated region.
325 // If special, the page was committed (only matters on windows)
326 if (!os::protect_memory(_base, _noaccess_prefix, os::MEM_PROT_NONE, _special)) {
327 fatal("cannot protect protection page");
328 }
329 log_debug(gc, heap, coops)("Protected page at the reserved heap base: "
330 PTR_FORMAT " / " INTX_FORMAT " bytes",
331 p2i(_base),
332 _noaccess_prefix);
333 assert(Universe::narrow_oop_use_implicit_null_checks() == true, "not initialized?");
334 } else {
335 Universe::set_narrow_oop_use_implicit_null_checks(false);
336 }
337 }
338
339 _base += _noaccess_prefix;
340 _size -= _noaccess_prefix;
341 assert(((uintptr_t)_base % _alignment == 0), "must be exactly of required alignment");
342 }
343
344 // Tries to allocate memory of size 'size' at address requested_address with alignment 'alignment'.
345 // Does not check whether the reserved memory actually is at requested_address, as the memory returned
346 // might still fulfill the wishes of the caller.
347 // Assures the memory is aligned to 'alignment'.
348 // NOTE: If ReservedHeapSpace already points to some reserved memory this is freed, first.
349 void ReservedHeapSpace::try_reserve_heap(size_t size,
350 size_t alignment,
351 bool large,
352 char* requested_address) {
353 if (_base != NULL) {
354 // We tried before, but we didn't like the address delivered.
355 release();
356 }
357
358 // If OS doesn't support demand paging for large page memory, we need
359 // to use reserve_memory_special() to reserve and pin the entire region.
360 // If there is a backing file directory for this space then whether
361 // large pages are allocated is up to the filesystem of the backing file.
362 // So we ignore the UseLargePages flag in this case.
363 bool special = large && !os::can_commit_large_page_memory();
364 if (special && _fd_for_heap != -1) {
365 special = false;
366 if (UseLargePages && (!FLAG_IS_DEFAULT(UseLargePages) ||
367 !FLAG_IS_DEFAULT(LargePageSizeInBytes))) {
368 log_debug(gc, heap)("Cannot allocate large pages for Java Heap when AllocateHeapAt option is set.");
369 }
370 }
371 char* base = NULL;
372
373 log_trace(gc, heap, coops)("Trying to allocate at address " PTR_FORMAT
374 " heap of size " SIZE_FORMAT_HEX,
375 p2i(requested_address),
376 size);
377
378 if (special) {
379 base = os::reserve_memory_special(size, alignment, requested_address, false);
380
381 if (base != NULL) {
382 // Check alignment constraints.
383 assert((uintptr_t) base % alignment == 0,
384 "Large pages returned a non-aligned address, base: "
385 PTR_FORMAT " alignment: " SIZE_FORMAT_HEX,
386 p2i(base), alignment);
387 _special = true;
388 }
389 }
390
391 if (base == NULL) {
392 // Failed; try to reserve regular memory below
393 if (UseLargePages && (!FLAG_IS_DEFAULT(UseLargePages) ||
394 !FLAG_IS_DEFAULT(LargePageSizeInBytes))) {
395 log_debug(gc, heap, coops)("Reserve regular memory without large pages");
396 }
397
398 // Optimistically assume that the OSes returns an aligned base pointer.
399 // When reserving a large address range, most OSes seem to align to at
400 // least 64K.
401
402 // If the memory was requested at a particular address, use
403 // os::attempt_reserve_memory_at() to avoid over mapping something
404 // important. If available space is not detected, return NULL.
405
406 if (requested_address != 0) {
407 base = os::attempt_reserve_memory_at(size, requested_address, _fd_for_heap);
408 } else {
409 base = os::reserve_memory(size, NULL, alignment, _fd_for_heap);
410 }
411 }
412 if (base == NULL) { return; }
413
414 // Done
415 _base = base;
416 _size = size;
417 _alignment = alignment;
418 // If heap is reserved with a backing file, the entire space has been committed. So set the _special flag to true
419 if (_fd_for_heap != -1) {
420 _special = true;
421 }
422 update_actual_page_size(large);
423
424 // Check alignment constraints
425 if ((((size_t)base) & (alignment - 1)) != 0) {
426 // Base not aligned, retry.
427 release();
428 }
429 }
430
431 void ReservedHeapSpace::try_reserve_range(char *highest_start,
432 char *lowest_start,
433 size_t attach_point_alignment,
434 char *aligned_heap_base_min_address,
435 char *upper_bound,
436 size_t size,
437 size_t alignment,
438 bool large) {
439 const size_t attach_range = highest_start - lowest_start;
440 // Cap num_attempts at possible number.
441 // At least one is possible even for 0 sized attach range.
442 const uint64_t num_attempts_possible = (attach_range / attach_point_alignment) + 1;
443 const uint64_t num_attempts_to_try = MIN2((uint64_t)HeapSearchSteps, num_attempts_possible);
444
445 const size_t stepsize = (attach_range == 0) ? // Only one try.
446 (size_t) highest_start : align_up(attach_range / num_attempts_to_try, attach_point_alignment);
447
448 // Try attach points from top to bottom.
449 char* attach_point = highest_start;
450 while (attach_point >= lowest_start &&
451 attach_point <= highest_start && // Avoid wrap around.
452 ((_base == NULL) ||
453 (_base < aligned_heap_base_min_address || _base + size > upper_bound))) {
454 try_reserve_heap(size, alignment, large, attach_point);
455 attach_point -= stepsize;
456 }
457 }
458
459 #define SIZE_64K ((uint64_t) UCONST64( 0x10000))
460 #define SIZE_256M ((uint64_t) UCONST64( 0x10000000))
461 #define SIZE_32G ((uint64_t) UCONST64( 0x800000000))
462
463 // Helper for heap allocation. Returns an array with addresses
464 // (OS-specific) which are suited for disjoint base mode. Array is
465 // NULL terminated.
466 static char** get_attach_addresses_for_disjoint_mode() {
467 static uint64_t addresses[] = {
468 2 * SIZE_32G,
469 3 * SIZE_32G,
470 4 * SIZE_32G,
471 8 * SIZE_32G,
472 10 * SIZE_32G,
473 1 * SIZE_64K * SIZE_32G,
474 2 * SIZE_64K * SIZE_32G,
475 3 * SIZE_64K * SIZE_32G,
476 4 * SIZE_64K * SIZE_32G,
477 16 * SIZE_64K * SIZE_32G,
478 32 * SIZE_64K * SIZE_32G,
479 34 * SIZE_64K * SIZE_32G,
480 0
481 };
482
483 // Sort out addresses smaller than HeapBaseMinAddress. This assumes
484 // the array is sorted.
485 uint i = 0;
486 while (addresses[i] != 0 &&
487 (addresses[i] < OopEncodingHeapMax || addresses[i] < HeapBaseMinAddress)) {
488 i++;
489 }
490 uint start = i;
491
492 // Avoid more steps than requested.
493 i = 0;
494 while (addresses[start+i] != 0) {
495 if (i == HeapSearchSteps) {
496 addresses[start+i] = 0;
497 break;
498 }
499 i++;
500 }
501
502 return (char**) &addresses[start];
503 }
504
505 void ReservedHeapSpace::initialize_compressed_heap(const size_t size, size_t alignment, bool large) {
506 guarantee(size + noaccess_prefix_size(alignment) <= OopEncodingHeapMax,
507 "can not allocate compressed oop heap for this size");
508 guarantee(alignment == MAX2(alignment, (size_t)os::vm_page_size()), "alignment too small");
509
510 const size_t granularity = os::vm_allocation_granularity();
511 assert((size & (granularity - 1)) == 0,
512 "size not aligned to os::vm_allocation_granularity()");
513 assert((alignment & (granularity - 1)) == 0,
514 "alignment not aligned to os::vm_allocation_granularity()");
515 assert(alignment == 0 || is_power_of_2((intptr_t)alignment),
516 "not a power of 2");
517
518 // The necessary attach point alignment for generated wish addresses.
519 // This is needed to increase the chance of attaching for mmap and shmat.
520 const size_t os_attach_point_alignment =
521 AIX_ONLY(SIZE_256M) // Known shm boundary alignment.
522 NOT_AIX(os::vm_allocation_granularity());
523 const size_t attach_point_alignment = lcm(alignment, os_attach_point_alignment);
524
525 char *aligned_heap_base_min_address = (char *)align_up((void *)HeapBaseMinAddress, alignment);
526 size_t noaccess_prefix = ((aligned_heap_base_min_address + size) > (char*)OopEncodingHeapMax) ?
527 noaccess_prefix_size(alignment) : 0;
528
529 // Attempt to alloc at user-given address.
530 if (!FLAG_IS_DEFAULT(HeapBaseMinAddress)) {
531 try_reserve_heap(size + noaccess_prefix, alignment, large, aligned_heap_base_min_address);
532 if (_base != aligned_heap_base_min_address) { // Enforce this exact address.
533 release();
534 }
535 }
536
537 // Keep heap at HeapBaseMinAddress.
538 if (_base == NULL) {
539
540 // Try to allocate the heap at addresses that allow efficient oop compression.
541 // Different schemes are tried, in order of decreasing optimization potential.
542 //
543 // For this, try_reserve_heap() is called with the desired heap base addresses.
544 // A call into the os layer to allocate at a given address can return memory
545 // at a different address than requested. Still, this might be memory at a useful
546 // address. try_reserve_heap() always returns this allocated memory, as only here
547 // the criteria for a good heap are checked.
548
549 // Attempt to allocate so that we can run without base and scale (32-Bit unscaled compressed oops).
550 // Give it several tries from top of range to bottom.
551 if (aligned_heap_base_min_address + size <= (char *)UnscaledOopHeapMax) {
552
553 // Calc address range within we try to attach (range of possible start addresses).
554 char* const highest_start = align_down((char *)UnscaledOopHeapMax - size, attach_point_alignment);
555 char* const lowest_start = align_up(aligned_heap_base_min_address, attach_point_alignment);
556 try_reserve_range(highest_start, lowest_start, attach_point_alignment,
557 aligned_heap_base_min_address, (char *)UnscaledOopHeapMax, size, alignment, large);
558 }
559
560 // zerobased: Attempt to allocate in the lower 32G.
561 // But leave room for the compressed class pointers, which is allocated above
562 // the heap.
563 char *zerobased_max = (char *)OopEncodingHeapMax;
564 const size_t class_space = align_up(CompressedClassSpaceSize, alignment);
565 // For small heaps, save some space for compressed class pointer
566 // space so it can be decoded with no base.
567 if (UseCompressedClassPointers && !UseSharedSpaces &&
568 OopEncodingHeapMax <= KlassEncodingMetaspaceMax &&
569 (uint64_t)(aligned_heap_base_min_address + size + class_space) <= KlassEncodingMetaspaceMax) {
570 zerobased_max = (char *)OopEncodingHeapMax - class_space;
571 }
572
573 // Give it several tries from top of range to bottom.
574 if (aligned_heap_base_min_address + size <= zerobased_max && // Zerobased theoretical possible.
575 ((_base == NULL) || // No previous try succeeded.
576 (_base + size > zerobased_max))) { // Unscaled delivered an arbitrary address.
577
578 // Calc address range within we try to attach (range of possible start addresses).
579 char *const highest_start = align_down(zerobased_max - size, attach_point_alignment);
580 // Need to be careful about size being guaranteed to be less
581 // than UnscaledOopHeapMax due to type constraints.
582 char *lowest_start = aligned_heap_base_min_address;
583 uint64_t unscaled_end = UnscaledOopHeapMax - size;
584 if (unscaled_end < UnscaledOopHeapMax) { // unscaled_end wrapped if size is large
585 lowest_start = MAX2(lowest_start, (char*)unscaled_end);
586 }
587 lowest_start = align_up(lowest_start, attach_point_alignment);
588 try_reserve_range(highest_start, lowest_start, attach_point_alignment,
589 aligned_heap_base_min_address, zerobased_max, size, alignment, large);
590 }
591
592 // Now we go for heaps with base != 0. We need a noaccess prefix to efficiently
593 // implement null checks.
594 noaccess_prefix = noaccess_prefix_size(alignment);
595
596 // Try to attach at addresses that are aligned to OopEncodingHeapMax. Disjointbase mode.
597 char** addresses = get_attach_addresses_for_disjoint_mode();
598 int i = 0;
599 while (addresses[i] && // End of array not yet reached.
600 ((_base == NULL) || // No previous try succeeded.
601 (_base + size > (char *)OopEncodingHeapMax && // Not zerobased or unscaled address.
602 !Universe::is_disjoint_heap_base_address((address)_base)))) { // Not disjoint address.
603 char* const attach_point = addresses[i];
604 assert(attach_point >= aligned_heap_base_min_address, "Flag support broken");
605 try_reserve_heap(size + noaccess_prefix, alignment, large, attach_point);
606 i++;
607 }
608
609 // Last, desperate try without any placement.
610 if (_base == NULL) {
611 log_trace(gc, heap, coops)("Trying to allocate at address NULL heap of size " SIZE_FORMAT_HEX, size + noaccess_prefix);
612 initialize(size + noaccess_prefix, alignment, large, NULL, false);
613 }
614 }
615 }
616
617 ReservedHeapSpace::ReservedHeapSpace(size_t size, size_t alignment, bool large, const char* heap_allocation_directory) : ReservedSpace() {
618
619 if (size == 0) {
620 return;
621 }
622
623 if (heap_allocation_directory != NULL) {
624 _fd_for_heap = os::create_file_for_heap(heap_allocation_directory);
625 if (_fd_for_heap == -1) {
626 vm_exit_during_initialization(
627 err_msg("Could not create file for Heap at location %s", heap_allocation_directory));
628 }
629 }
630
631 // Heap size should be aligned to alignment, too.
632 guarantee(is_aligned(size, alignment), "set by caller");
633
634 if (UseCompressedOops) {
635 initialize_compressed_heap(size, alignment, large);
636 if (_size > size) {
637 // We allocated heap with noaccess prefix.
638 // It can happen we get a zerobased/unscaled heap with noaccess prefix,
639 // if we had to try at arbitrary address.
640 establish_noaccess_prefix();
641 }
642 } else {
643 initialize(size, alignment, large, NULL, false);
644 }
645
646 assert(markOopDesc::encode_pointer_as_mark(_base)->decode_pointer() == _base,
647 "area must be distinguishable from marks for mark-sweep");
648 assert(markOopDesc::encode_pointer_as_mark(&_base[size])->decode_pointer() == &_base[size],
649 "area must be distinguishable from marks for mark-sweep");
650
651 if (base() != NULL) {
652 MemTracker::record_virtual_memory_type((address)base(), mtJavaHeap);
653 }
654
655 if (_fd_for_heap != -1) {
656 os::close(_fd_for_heap);
657 }
658 }
659
660 // Reserve space for code segment. Same as Java heap only we mark this as
661 // executable.
662 ReservedCodeSpace::ReservedCodeSpace(size_t r_size,
663 size_t rs_align,
664 bool large) :
665 ReservedSpace(r_size, rs_align, large, /*executable*/ true) {
666 MemTracker::record_virtual_memory_type((address)base(), mtCode);
667 }
668
669 // VirtualSpace
670
671 VirtualSpace::VirtualSpace() {
672 _low_boundary = NULL;
673 _high_boundary = NULL;
674 _low = NULL;
675 _high = NULL;
676 _lower_high = NULL;
677 _middle_high = NULL;
678 _upper_high = NULL;
679 _lower_high_boundary = NULL;
680 _middle_high_boundary = NULL;
681 _upper_high_boundary = NULL;
682 _lower_alignment = 0;
683 _middle_alignment = 0;
684 _upper_alignment = 0;
685 _special = false;
686 _executable = false;
687 }
688
689
690 bool VirtualSpace::initialize(ReservedSpace rs, size_t committed_size) {
691 const size_t max_commit_granularity = os::page_size_for_region_unaligned(rs.size(), 1);
692 return initialize_with_granularity(rs, committed_size, max_commit_granularity);
693 }
694
695 bool VirtualSpace::initialize_with_granularity(ReservedSpace rs, size_t committed_size, size_t max_commit_granularity) {
696 if(!rs.is_reserved()) return false; // allocation failed.
697 assert(_low_boundary == NULL, "VirtualSpace already initialized");
698 assert(max_commit_granularity > 0, "Granularity must be non-zero.");
699
700 _low_boundary = rs.base();
701 _high_boundary = low_boundary() + rs.size();
702
703 _low = low_boundary();
704 _high = low();
705
706 _special = rs.special();
707 _executable = rs.executable();
708
709 // When a VirtualSpace begins life at a large size, make all future expansion
710 // and shrinking occur aligned to a granularity of large pages. This avoids
711 // fragmentation of physical addresses that inhibits the use of large pages
712 // by the OS virtual memory system. Empirically, we see that with a 4MB
713 // page size, the only spaces that get handled this way are codecache and
714 // the heap itself, both of which provide a substantial performance
715 // boost in many benchmarks when covered by large pages.
716 //
717 // No attempt is made to force large page alignment at the very top and
718 // bottom of the space if they are not aligned so already.
719 _lower_alignment = os::vm_page_size();
720 _middle_alignment = max_commit_granularity;
721 _upper_alignment = os::vm_page_size();
722
723 // End of each region
724 _lower_high_boundary = align_up(low_boundary(), middle_alignment());
725 _middle_high_boundary = align_down(high_boundary(), middle_alignment());
726 _upper_high_boundary = high_boundary();
727
728 // High address of each region
729 _lower_high = low_boundary();
730 _middle_high = lower_high_boundary();
731 _upper_high = middle_high_boundary();
732
733 // commit to initial size
734 if (committed_size > 0) {
735 if (!expand_by(committed_size)) {
736 return false;
737 }
738 }
739 return true;
740 }
741
742
743 VirtualSpace::~VirtualSpace() {
744 release();
745 }
746
747
748 void VirtualSpace::release() {
749 // This does not release memory it reserved.
750 // Caller must release via rs.release();
751 _low_boundary = NULL;
752 _high_boundary = NULL;
753 _low = NULL;
754 _high = NULL;
755 _lower_high = NULL;
756 _middle_high = NULL;
757 _upper_high = NULL;
758 _lower_high_boundary = NULL;
759 _middle_high_boundary = NULL;
760 _upper_high_boundary = NULL;
761 _lower_alignment = 0;
762 _middle_alignment = 0;
763 _upper_alignment = 0;
764 _special = false;
765 _executable = false;
766 }
767
768
769 size_t VirtualSpace::committed_size() const {
770 return pointer_delta(high(), low(), sizeof(char));
771 }
772
773
774 size_t VirtualSpace::reserved_size() const {
775 return pointer_delta(high_boundary(), low_boundary(), sizeof(char));
776 }
777
778
779 size_t VirtualSpace::uncommitted_size() const {
780 return reserved_size() - committed_size();
781 }
782
783 size_t VirtualSpace::actual_committed_size() const {
784 // Special VirtualSpaces commit all reserved space up front.
785 if (special()) {
786 return reserved_size();
787 }
788
789 size_t committed_low = pointer_delta(_lower_high, _low_boundary, sizeof(char));
790 size_t committed_middle = pointer_delta(_middle_high, _lower_high_boundary, sizeof(char));
791 size_t committed_high = pointer_delta(_upper_high, _middle_high_boundary, sizeof(char));
792
793 #ifdef ASSERT
794 size_t lower = pointer_delta(_lower_high_boundary, _low_boundary, sizeof(char));
795 size_t middle = pointer_delta(_middle_high_boundary, _lower_high_boundary, sizeof(char));
796 size_t upper = pointer_delta(_upper_high_boundary, _middle_high_boundary, sizeof(char));
797
798 if (committed_high > 0) {
799 assert(committed_low == lower, "Must be");
800 assert(committed_middle == middle, "Must be");
801 }
802
803 if (committed_middle > 0) {
804 assert(committed_low == lower, "Must be");
805 }
806 if (committed_middle < middle) {
807 assert(committed_high == 0, "Must be");
808 }
809
810 if (committed_low < lower) {
811 assert(committed_high == 0, "Must be");
812 assert(committed_middle == 0, "Must be");
813 }
814 #endif
815
816 return committed_low + committed_middle + committed_high;
817 }
818
819
820 bool VirtualSpace::contains(const void* p) const {
821 return low() <= (const char*) p && (const char*) p < high();
822 }
823
824 static void pretouch_expanded_memory(void* start, void* end) {
825 assert(is_aligned(start, os::vm_page_size()), "Unexpected alignment");
826 assert(is_aligned(end, os::vm_page_size()), "Unexpected alignment");
827
828 os::pretouch_memory(start, end);
829 }
830
831 static bool commit_expanded(char* start, size_t size, size_t alignment, bool pre_touch, bool executable) {
832 if (os::commit_memory(start, size, alignment, executable)) {
833 if (pre_touch || AlwaysPreTouch) {
834 pretouch_expanded_memory(start, start + size);
835 }
836 return true;
837 }
838
839 debug_only(warning(
840 "INFO: os::commit_memory(" PTR_FORMAT ", " PTR_FORMAT
841 " size=" SIZE_FORMAT ", executable=%d) failed",
842 p2i(start), p2i(start + size), size, executable);)
843
844 return false;
845 }
846
847 /*
848 First we need to determine if a particular virtual space is using large
849 pages. This is done at the initialize function and only virtual spaces
850 that are larger than LargePageSizeInBytes use large pages. Once we
851 have determined this, all expand_by and shrink_by calls must grow and
852 shrink by large page size chunks. If a particular request
853 is within the current large page, the call to commit and uncommit memory
854 can be ignored. In the case that the low and high boundaries of this
855 space is not large page aligned, the pages leading to the first large
856 page address and the pages after the last large page address must be
857 allocated with default pages.
858 */
859 bool VirtualSpace::expand_by(size_t bytes, bool pre_touch) {
860 if (uncommitted_size() < bytes) {
861 return false;
862 }
863
864 if (special()) {
865 // don't commit memory if the entire space is pinned in memory
866 _high += bytes;
867 return true;
868 }
869
870 char* previous_high = high();
871 char* unaligned_new_high = high() + bytes;
872 assert(unaligned_new_high <= high_boundary(), "cannot expand by more than upper boundary");
873
874 // Calculate where the new high for each of the regions should be. If
875 // the low_boundary() and high_boundary() are LargePageSizeInBytes aligned
876 // then the unaligned lower and upper new highs would be the
877 // lower_high() and upper_high() respectively.
878 char* unaligned_lower_new_high = MIN2(unaligned_new_high, lower_high_boundary());
879 char* unaligned_middle_new_high = MIN2(unaligned_new_high, middle_high_boundary());
880 char* unaligned_upper_new_high = MIN2(unaligned_new_high, upper_high_boundary());
881
882 // Align the new highs based on the regions alignment. lower and upper
883 // alignment will always be default page size. middle alignment will be
884 // LargePageSizeInBytes if the actual size of the virtual space is in
885 // fact larger than LargePageSizeInBytes.
886 char* aligned_lower_new_high = align_up(unaligned_lower_new_high, lower_alignment());
887 char* aligned_middle_new_high = align_up(unaligned_middle_new_high, middle_alignment());
888 char* aligned_upper_new_high = align_up(unaligned_upper_new_high, upper_alignment());
889
890 // Determine which regions need to grow in this expand_by call.
891 // If you are growing in the lower region, high() must be in that
892 // region so calculate the size based on high(). For the middle and
893 // upper regions, determine the starting point of growth based on the
894 // location of high(). By getting the MAX of the region's low address
895 // (or the previous region's high address) and high(), we can tell if it
896 // is an intra or inter region growth.
897 size_t lower_needs = 0;
898 if (aligned_lower_new_high > lower_high()) {
899 lower_needs = pointer_delta(aligned_lower_new_high, lower_high(), sizeof(char));
900 }
901 size_t middle_needs = 0;
902 if (aligned_middle_new_high > middle_high()) {
903 middle_needs = pointer_delta(aligned_middle_new_high, middle_high(), sizeof(char));
904 }
905 size_t upper_needs = 0;
906 if (aligned_upper_new_high > upper_high()) {
907 upper_needs = pointer_delta(aligned_upper_new_high, upper_high(), sizeof(char));
908 }
909
910 // Check contiguity.
911 assert(low_boundary() <= lower_high() && lower_high() <= lower_high_boundary(),
912 "high address must be contained within the region");
913 assert(lower_high_boundary() <= middle_high() && middle_high() <= middle_high_boundary(),
914 "high address must be contained within the region");
915 assert(middle_high_boundary() <= upper_high() && upper_high() <= upper_high_boundary(),
916 "high address must be contained within the region");
917
918 // Commit regions
919 if (lower_needs > 0) {
920 assert(lower_high() + lower_needs <= lower_high_boundary(), "must not expand beyond region");
921 if (!commit_expanded(lower_high(), lower_needs, _lower_alignment, pre_touch, _executable)) {
922 return false;
923 }
924 _lower_high += lower_needs;
925 }
926
927 if (middle_needs > 0) {
928 assert(middle_high() + middle_needs <= middle_high_boundary(), "must not expand beyond region");
929 if (!commit_expanded(middle_high(), middle_needs, _middle_alignment, pre_touch, _executable)) {
930 return false;
931 }
932 _middle_high += middle_needs;
933 }
934
935 if (upper_needs > 0) {
936 assert(upper_high() + upper_needs <= upper_high_boundary(), "must not expand beyond region");
937 if (!commit_expanded(upper_high(), upper_needs, _upper_alignment, pre_touch, _executable)) {
938 return false;
939 }
940 _upper_high += upper_needs;
941 }
942
943 _high += bytes;
944 return true;
945 }
946
947 // A page is uncommitted if the contents of the entire page is deemed unusable.
948 // Continue to decrement the high() pointer until it reaches a page boundary
949 // in which case that particular page can now be uncommitted.
950 void VirtualSpace::shrink_by(size_t size) {
951 if (committed_size() < size)
952 fatal("Cannot shrink virtual space to negative size");
953
954 if (special()) {
955 // don't uncommit if the entire space is pinned in memory
956 _high -= size;
957 return;
958 }
959
960 char* unaligned_new_high = high() - size;
961 assert(unaligned_new_high >= low_boundary(), "cannot shrink past lower boundary");
962
963 // Calculate new unaligned address
964 char* unaligned_upper_new_high =
965 MAX2(unaligned_new_high, middle_high_boundary());
966 char* unaligned_middle_new_high =
967 MAX2(unaligned_new_high, lower_high_boundary());
968 char* unaligned_lower_new_high =
969 MAX2(unaligned_new_high, low_boundary());
970
971 // Align address to region's alignment
972 char* aligned_upper_new_high = align_up(unaligned_upper_new_high, upper_alignment());
973 char* aligned_middle_new_high = align_up(unaligned_middle_new_high, middle_alignment());
974 char* aligned_lower_new_high = align_up(unaligned_lower_new_high, lower_alignment());
975
976 // Determine which regions need to shrink
977 size_t upper_needs = 0;
978 if (aligned_upper_new_high < upper_high()) {
979 upper_needs =
980 pointer_delta(upper_high(), aligned_upper_new_high, sizeof(char));
981 }
982 size_t middle_needs = 0;
983 if (aligned_middle_new_high < middle_high()) {
984 middle_needs =
985 pointer_delta(middle_high(), aligned_middle_new_high, sizeof(char));
986 }
987 size_t lower_needs = 0;
988 if (aligned_lower_new_high < lower_high()) {
989 lower_needs =
990 pointer_delta(lower_high(), aligned_lower_new_high, sizeof(char));
991 }
992
993 // Check contiguity.
994 assert(middle_high_boundary() <= upper_high() &&
995 upper_high() <= upper_high_boundary(),
996 "high address must be contained within the region");
997 assert(lower_high_boundary() <= middle_high() &&
998 middle_high() <= middle_high_boundary(),
999 "high address must be contained within the region");
1000 assert(low_boundary() <= lower_high() &&
1001 lower_high() <= lower_high_boundary(),
1002 "high address must be contained within the region");
1003
1004 // Uncommit
1005 if (upper_needs > 0) {
1006 assert(middle_high_boundary() <= aligned_upper_new_high &&
1007 aligned_upper_new_high + upper_needs <= upper_high_boundary(),
1008 "must not shrink beyond region");
1009 if (!os::uncommit_memory(aligned_upper_new_high, upper_needs)) {
1010 debug_only(warning("os::uncommit_memory failed"));
1011 return;
1012 } else {
1013 _upper_high -= upper_needs;
1014 }
1015 }
1016 if (middle_needs > 0) {
1017 assert(lower_high_boundary() <= aligned_middle_new_high &&
1018 aligned_middle_new_high + middle_needs <= middle_high_boundary(),
1019 "must not shrink beyond region");
1020 if (!os::uncommit_memory(aligned_middle_new_high, middle_needs)) {
1021 debug_only(warning("os::uncommit_memory failed"));
1022 return;
1023 } else {
1024 _middle_high -= middle_needs;
1025 }
1026 }
1027 if (lower_needs > 0) {
1028 assert(low_boundary() <= aligned_lower_new_high &&
1029 aligned_lower_new_high + lower_needs <= lower_high_boundary(),
1030 "must not shrink beyond region");
1031 if (!os::uncommit_memory(aligned_lower_new_high, lower_needs)) {
1032 debug_only(warning("os::uncommit_memory failed"));
1033 return;
1034 } else {
1035 _lower_high -= lower_needs;
1036 }
1037 }
1038
1039 _high -= size;
1040 }
1041
1042 #ifndef PRODUCT
1043 void VirtualSpace::check_for_contiguity() {
1044 // Check contiguity.
1045 assert(low_boundary() <= lower_high() &&
1046 lower_high() <= lower_high_boundary(),
1047 "high address must be contained within the region");
1048 assert(lower_high_boundary() <= middle_high() &&
1049 middle_high() <= middle_high_boundary(),
1050 "high address must be contained within the region");
1051 assert(middle_high_boundary() <= upper_high() &&
1052 upper_high() <= upper_high_boundary(),
1053 "high address must be contained within the region");
1054 assert(low() >= low_boundary(), "low");
1055 assert(low_boundary() <= lower_high_boundary(), "lower high boundary");
1056 assert(upper_high_boundary() <= high_boundary(), "upper high boundary");
1057 assert(high() <= upper_high(), "upper high");
1058 }
1059
1060 void VirtualSpace::print_on(outputStream* out) {
1061 out->print ("Virtual space:");
1062 if (special()) out->print(" (pinned in memory)");
1063 out->cr();
1064 out->print_cr(" - committed: " SIZE_FORMAT, committed_size());
1065 out->print_cr(" - reserved: " SIZE_FORMAT, reserved_size());
1066 out->print_cr(" - [low, high]: [" INTPTR_FORMAT ", " INTPTR_FORMAT "]", p2i(low()), p2i(high()));
1067 out->print_cr(" - [low_b, high_b]: [" INTPTR_FORMAT ", " INTPTR_FORMAT "]", p2i(low_boundary()), p2i(high_boundary()));
1068 }
1069
1070 void VirtualSpace::print() {
1071 print_on(tty);
1072 }
1073
1074 /////////////// Unit tests ///////////////
1075
1076 #ifndef PRODUCT
1077
1078 class TestReservedSpace : AllStatic {
1079 public:
1080 static void small_page_write(void* addr, size_t size) {
1081 size_t page_size = os::vm_page_size();
1082
1083 char* end = (char*)addr + size;
1084 for (char* p = (char*)addr; p < end; p += page_size) {
1085 *p = 1;
1086 }
1087 }
1088
1089 static void release_memory_for_test(ReservedSpace rs) {
1090 if (rs.special()) {
1091 guarantee(os::release_memory_special(rs.base(), rs.size()), "Shouldn't fail");
1092 } else {
1093 guarantee(os::release_memory(rs.base(), rs.size()), "Shouldn't fail");
1094 }
1095 }
1096
1097 static void test_reserved_space1(size_t size, size_t alignment) {
1098 assert(is_aligned(size, alignment), "Incorrect input parameters");
1099
1100 ReservedSpace rs(size, // size
1101 alignment, // alignment
1102 UseLargePages, // large
1103 (char *)NULL); // requested_address
1104
1105 assert(rs.base() != NULL, "Must be");
1106 assert(rs.size() == size, "Must be");
1107
1108 assert(is_aligned(rs.base(), alignment), "aligned sizes should always give aligned addresses");
1109 assert(is_aligned(rs.size(), alignment), "aligned sizes should always give aligned addresses");
1110
1111 if (rs.special()) {
1112 small_page_write(rs.base(), size);
1113 }
1114
1115 release_memory_for_test(rs);
1116 }
1117
1118 static void test_reserved_space2(size_t size) {
1119 assert(is_aligned(size, os::vm_allocation_granularity()), "Must be at least AG aligned");
1120
1121 ReservedSpace rs(size);
1122
1123 assert(rs.base() != NULL, "Must be");
1124 assert(rs.size() == size, "Must be");
1125
1126 if (rs.special()) {
1127 small_page_write(rs.base(), size);
1128 }
1129
1130 release_memory_for_test(rs);
1131 }
1132
1133 static void test_reserved_space3(size_t size, size_t alignment, bool maybe_large) {
1134 if (size < alignment) {
1135 // Tests might set -XX:LargePageSizeInBytes=<small pages> and cause unexpected input arguments for this test.
1136 assert((size_t)os::vm_page_size() == os::large_page_size(), "Test needs further refinement");
1137 return;
1138 }
1139
1140 assert(is_aligned(size, os::vm_allocation_granularity()), "Must be at least AG aligned");
1141 assert(is_aligned(size, alignment), "Must be at least aligned against alignment");
1142
1143 bool large = maybe_large && UseLargePages && size >= os::large_page_size();
1144
1145 ReservedSpace rs(size, alignment, large, false);
1146
1147 assert(rs.base() != NULL, "Must be");
1148 assert(rs.size() == size, "Must be");
1149
1150 if (rs.special()) {
1151 small_page_write(rs.base(), size);
1152 }
1153
1154 release_memory_for_test(rs);
1155 }
1156
1157
1158 static void test_reserved_space1() {
1159 size_t size = 2 * 1024 * 1024;
1160 size_t ag = os::vm_allocation_granularity();
1161
1162 test_reserved_space1(size, ag);
1163 test_reserved_space1(size * 2, ag);
1164 test_reserved_space1(size * 10, ag);
1165 }
1166
1167 static void test_reserved_space2() {
1168 size_t size = 2 * 1024 * 1024;
1169 size_t ag = os::vm_allocation_granularity();
1170
1171 test_reserved_space2(size * 1);
1172 test_reserved_space2(size * 2);
1173 test_reserved_space2(size * 10);
1174 test_reserved_space2(ag);
1175 test_reserved_space2(size - ag);
1176 test_reserved_space2(size);
1177 test_reserved_space2(size + ag);
1178 test_reserved_space2(size * 2);
1179 test_reserved_space2(size * 2 - ag);
1180 test_reserved_space2(size * 2 + ag);
1181 test_reserved_space2(size * 3);
1182 test_reserved_space2(size * 3 - ag);
1183 test_reserved_space2(size * 3 + ag);
1184 test_reserved_space2(size * 10);
1185 test_reserved_space2(size * 10 + size / 2);
1186 }
1187
1188 static void test_reserved_space3() {
1189 size_t ag = os::vm_allocation_granularity();
1190
1191 test_reserved_space3(ag, ag , false);
1192 test_reserved_space3(ag * 2, ag , false);
1193 test_reserved_space3(ag * 3, ag , false);
1194 test_reserved_space3(ag * 2, ag * 2, false);
1195 test_reserved_space3(ag * 4, ag * 2, false);
1196 test_reserved_space3(ag * 8, ag * 2, false);
1197 test_reserved_space3(ag * 4, ag * 4, false);
1198 test_reserved_space3(ag * 8, ag * 4, false);
1199 test_reserved_space3(ag * 16, ag * 4, false);
1200
1201 if (UseLargePages) {
1202 size_t lp = os::large_page_size();
1203
1204 // Without large pages
1205 test_reserved_space3(lp, ag * 4, false);
1206 test_reserved_space3(lp * 2, ag * 4, false);
1207 test_reserved_space3(lp * 4, ag * 4, false);
1208 test_reserved_space3(lp, lp , false);
1209 test_reserved_space3(lp * 2, lp , false);
1210 test_reserved_space3(lp * 3, lp , false);
1211 test_reserved_space3(lp * 2, lp * 2, false);
1212 test_reserved_space3(lp * 4, lp * 2, false);
1213 test_reserved_space3(lp * 8, lp * 2, false);
1214
1215 // With large pages
1216 test_reserved_space3(lp, ag * 4 , true);
1217 test_reserved_space3(lp * 2, ag * 4, true);
1218 test_reserved_space3(lp * 4, ag * 4, true);
1219 test_reserved_space3(lp, lp , true);
1220 test_reserved_space3(lp * 2, lp , true);
1221 test_reserved_space3(lp * 3, lp , true);
1222 test_reserved_space3(lp * 2, lp * 2, true);
1223 test_reserved_space3(lp * 4, lp * 2, true);
1224 test_reserved_space3(lp * 8, lp * 2, true);
1225 }
1226 }
1227
1228 static void test_reserved_space() {
1229 test_reserved_space1();
1230 test_reserved_space2();
1231 test_reserved_space3();
1232 }
1233 };
1234
1235 void TestReservedSpace_test() {
1236 TestReservedSpace::test_reserved_space();
1237 }
1238
1239 #define assert_equals(actual, expected) \
1240 assert(actual == expected, \
1241 "Got " SIZE_FORMAT " expected " \
1242 SIZE_FORMAT, actual, expected);
1243
1244 #define assert_ge(value1, value2) \
1245 assert(value1 >= value2, \
1246 "'" #value1 "': " SIZE_FORMAT " '" \
1247 #value2 "': " SIZE_FORMAT, value1, value2);
1248
1249 #define assert_lt(value1, value2) \
1250 assert(value1 < value2, \
1251 "'" #value1 "': " SIZE_FORMAT " '" \
1252 #value2 "': " SIZE_FORMAT, value1, value2);
1253
1254
1255 class TestVirtualSpace : AllStatic {
1256 enum TestLargePages {
1257 Default,
1258 Disable,
1259 Reserve,
1260 Commit
1261 };
1262
1263 static ReservedSpace reserve_memory(size_t reserve_size_aligned, TestLargePages mode) {
1264 switch(mode) {
1265 default:
1266 case Default:
1267 case Reserve:
1268 return ReservedSpace(reserve_size_aligned);
1269 case Disable:
1270 case Commit:
1271 return ReservedSpace(reserve_size_aligned,
1272 os::vm_allocation_granularity(),
1273 /* large */ false, /* exec */ false);
1274 }
1275 }
1276
1277 static bool initialize_virtual_space(VirtualSpace& vs, ReservedSpace rs, TestLargePages mode) {
1278 switch(mode) {
1279 default:
1280 case Default:
1281 case Reserve:
1282 return vs.initialize(rs, 0);
1283 case Disable:
1284 return vs.initialize_with_granularity(rs, 0, os::vm_page_size());
1285 case Commit:
1286 return vs.initialize_with_granularity(rs, 0, os::page_size_for_region_unaligned(rs.size(), 1));
1287 }
1288 }
1289
1290 public:
1291 static void test_virtual_space_actual_committed_space(size_t reserve_size, size_t commit_size,
1292 TestLargePages mode = Default) {
1293 size_t granularity = os::vm_allocation_granularity();
1294 size_t reserve_size_aligned = align_up(reserve_size, granularity);
1295
1296 ReservedSpace reserved = reserve_memory(reserve_size_aligned, mode);
1297
1298 assert(reserved.is_reserved(), "Must be");
1299
1300 VirtualSpace vs;
1301 bool initialized = initialize_virtual_space(vs, reserved, mode);
1302 assert(initialized, "Failed to initialize VirtualSpace");
1303
1304 vs.expand_by(commit_size, false);
1305
1306 if (vs.special()) {
1307 assert_equals(vs.actual_committed_size(), reserve_size_aligned);
1308 } else {
1309 assert_ge(vs.actual_committed_size(), commit_size);
1310 // Approximate the commit granularity.
1311 // Make sure that we don't commit using large pages
1312 // if large pages has been disabled for this VirtualSpace.
1313 size_t commit_granularity = (mode == Disable || !UseLargePages) ?
1314 os::vm_page_size() : os::large_page_size();
1315 assert_lt(vs.actual_committed_size(), commit_size + commit_granularity);
1316 }
1317
1318 reserved.release();
1319 }
1320
1321 static void test_virtual_space_actual_committed_space_one_large_page() {
1322 if (!UseLargePages) {
1323 return;
1324 }
1325
1326 size_t large_page_size = os::large_page_size();
1327
1328 ReservedSpace reserved(large_page_size, large_page_size, true, false);
1329
1330 assert(reserved.is_reserved(), "Must be");
1331
1332 VirtualSpace vs;
1333 bool initialized = vs.initialize(reserved, 0);
1334 assert(initialized, "Failed to initialize VirtualSpace");
1335
1336 vs.expand_by(large_page_size, false);
1337
1338 assert_equals(vs.actual_committed_size(), large_page_size);
1339
1340 reserved.release();
1341 }
1342
1343 static void test_virtual_space_actual_committed_space() {
1344 test_virtual_space_actual_committed_space(4 * K, 0);
1345 test_virtual_space_actual_committed_space(4 * K, 4 * K);
1346 test_virtual_space_actual_committed_space(8 * K, 0);
1347 test_virtual_space_actual_committed_space(8 * K, 4 * K);
1348 test_virtual_space_actual_committed_space(8 * K, 8 * K);
1349 test_virtual_space_actual_committed_space(12 * K, 0);
1350 test_virtual_space_actual_committed_space(12 * K, 4 * K);
1351 test_virtual_space_actual_committed_space(12 * K, 8 * K);
1352 test_virtual_space_actual_committed_space(12 * K, 12 * K);
1353 test_virtual_space_actual_committed_space(64 * K, 0);
1354 test_virtual_space_actual_committed_space(64 * K, 32 * K);
1355 test_virtual_space_actual_committed_space(64 * K, 64 * K);
1356 test_virtual_space_actual_committed_space(2 * M, 0);
1357 test_virtual_space_actual_committed_space(2 * M, 4 * K);
1358 test_virtual_space_actual_committed_space(2 * M, 64 * K);
1359 test_virtual_space_actual_committed_space(2 * M, 1 * M);
1360 test_virtual_space_actual_committed_space(2 * M, 2 * M);
1361 test_virtual_space_actual_committed_space(10 * M, 0);
1362 test_virtual_space_actual_committed_space(10 * M, 4 * K);
1363 test_virtual_space_actual_committed_space(10 * M, 8 * K);
1364 test_virtual_space_actual_committed_space(10 * M, 1 * M);
1365 test_virtual_space_actual_committed_space(10 * M, 2 * M);
1366 test_virtual_space_actual_committed_space(10 * M, 5 * M);
1367 test_virtual_space_actual_committed_space(10 * M, 10 * M);
1368 }
1369
1370 static void test_virtual_space_disable_large_pages() {
1371 if (!UseLargePages) {
1372 return;
1373 }
1374 // These test cases verify that if we force VirtualSpace to disable large pages
1375 test_virtual_space_actual_committed_space(10 * M, 0, Disable);
1376 test_virtual_space_actual_committed_space(10 * M, 4 * K, Disable);
1377 test_virtual_space_actual_committed_space(10 * M, 8 * K, Disable);
1378 test_virtual_space_actual_committed_space(10 * M, 1 * M, Disable);
1379 test_virtual_space_actual_committed_space(10 * M, 2 * M, Disable);
1380 test_virtual_space_actual_committed_space(10 * M, 5 * M, Disable);
1381 test_virtual_space_actual_committed_space(10 * M, 10 * M, Disable);
1382
1383 test_virtual_space_actual_committed_space(10 * M, 0, Reserve);
1384 test_virtual_space_actual_committed_space(10 * M, 4 * K, Reserve);
1385 test_virtual_space_actual_committed_space(10 * M, 8 * K, Reserve);
1386 test_virtual_space_actual_committed_space(10 * M, 1 * M, Reserve);
1387 test_virtual_space_actual_committed_space(10 * M, 2 * M, Reserve);
1388 test_virtual_space_actual_committed_space(10 * M, 5 * M, Reserve);
1389 test_virtual_space_actual_committed_space(10 * M, 10 * M, Reserve);
1390
1391 test_virtual_space_actual_committed_space(10 * M, 0, Commit);
1392 test_virtual_space_actual_committed_space(10 * M, 4 * K, Commit);
1393 test_virtual_space_actual_committed_space(10 * M, 8 * K, Commit);
1394 test_virtual_space_actual_committed_space(10 * M, 1 * M, Commit);
1395 test_virtual_space_actual_committed_space(10 * M, 2 * M, Commit);
1396 test_virtual_space_actual_committed_space(10 * M, 5 * M, Commit);
1397 test_virtual_space_actual_committed_space(10 * M, 10 * M, Commit);
1398 }
1399
1400 static void test_virtual_space() {
1401 test_virtual_space_actual_committed_space();
1402 test_virtual_space_actual_committed_space_one_large_page();
1403 test_virtual_space_disable_large_pages();
1404 }
1405 };
1406
1407 void TestVirtualSpace_test() {
1408 TestVirtualSpace::test_virtual_space();
1409 }
1410
1411 #endif // PRODUCT
1412
1413 #endif