1 /*
2 * Copyright (c) 1997, 2016, 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 "code/codeCacheExtensions.hpp"
27 #include "logging/log.hpp"
28 #include "memory/resourceArea.hpp"
29 #include "memory/virtualspace.hpp"
30 #include "oops/markOop.hpp"
31 #include "oops/oop.inline.hpp"
32 #include "services/memTracker.hpp"
33
34 // ReservedSpace
35
36 // Dummy constructor
37 ReservedSpace::ReservedSpace() : _base(NULL), _size(0), _noaccess_prefix(0),
38 _alignment(0), _special(false), _executable(false) {
39 }
40
41 ReservedSpace::ReservedSpace(size_t size, size_t preferred_page_size) {
42 bool has_preferred_page_size = preferred_page_size != 0;
43 // Want to use large pages where possible and pad with small pages.
44 size_t page_size = has_preferred_page_size ? preferred_page_size : os::page_size_for_region_unaligned(size, 1);
45 bool large_pages = page_size != (size_t)os::vm_page_size();
46 size_t alignment;
47 if (large_pages && has_preferred_page_size) {
48 alignment = MAX2(page_size, (size_t)os::vm_allocation_granularity());
49 // ReservedSpace initialization requires size to be aligned to the given
50 // alignment. Align the size up.
51 size = align_size_up(size, alignment);
52 } else {
53 // Don't force the alignment to be large page aligned,
54 // since that will waste memory.
55 alignment = os::vm_allocation_granularity();
56 }
57 initialize(size, alignment, large_pages, NULL, false);
58 }
59
60 ReservedSpace::ReservedSpace(size_t size, size_t alignment,
61 bool large,
62 char* requested_address) {
63 initialize(size, alignment, large, requested_address, false);
64 }
65
66 ReservedSpace::ReservedSpace(size_t size, size_t alignment,
67 bool large,
68 bool executable) {
69 initialize(size, alignment, large, NULL, executable);
70 }
71
72 // Helper method.
73 static bool failed_to_reserve_as_requested(char* base, char* requested_address,
74 const size_t size, bool special)
75 {
76 if (base == requested_address || requested_address == NULL)
77 return false; // did not fail
78
79 if (base != NULL) {
80 // Different reserve address may be acceptable in other cases
81 // but for compressed oops heap should be at requested address.
82 assert(UseCompressedOops, "currently requested address used only for compressed oops");
83 log_debug(gc, heap, coops)("Reserved memory not at requested address: " PTR_FORMAT " vs " PTR_FORMAT, p2i(base), p2i(requested_address));
84 // OS ignored requested address. Try different address.
85 if (special) {
86 if (!os::release_memory_special(base, size)) {
87 fatal("os::release_memory_special failed");
88 }
89 } else {
90 if (!os::release_memory(base, size)) {
91 fatal("os::release_memory failed");
92 }
93 }
94 }
95 return true;
96 }
97
98 void ReservedSpace::initialize(size_t size, size_t alignment, bool large,
99 char* requested_address,
100 bool executable) {
101 const size_t granularity = os::vm_allocation_granularity();
102 assert((size & (granularity - 1)) == 0,
103 "size not aligned to os::vm_allocation_granularity()");
104 assert((alignment & (granularity - 1)) == 0,
105 "alignment not aligned to os::vm_allocation_granularity()");
106 assert(alignment == 0 || is_power_of_2((intptr_t)alignment),
107 "not a power of 2");
108
109 alignment = MAX2(alignment, (size_t)os::vm_page_size());
110
111 _base = NULL;
112 _size = 0;
113 _special = false;
114 _executable = executable;
115 _alignment = 0;
116 _noaccess_prefix = 0;
117 if (size == 0) {
118 return;
119 }
120
121 // If OS doesn't support demand paging for large page memory, we need
122 // to use reserve_memory_special() to reserve and pin the entire region.
123 bool special = large && !os::can_commit_large_page_memory();
124 char* base = NULL;
125
126 if (special) {
127
128 base = os::reserve_memory_special(size, alignment, requested_address, executable);
129
130 if (base != NULL) {
131 if (failed_to_reserve_as_requested(base, requested_address, size, true)) {
132 // OS ignored requested address. Try different address.
133 return;
134 }
135 // Check alignment constraints.
136 assert((uintptr_t) base % alignment == 0,
137 "Large pages returned a non-aligned address, base: "
138 PTR_FORMAT " alignment: " SIZE_FORMAT_HEX,
139 p2i(base), alignment);
140 _special = true;
141 } else {
142 // failed; try to reserve regular memory below
143 if (UseLargePages && (!FLAG_IS_DEFAULT(UseLargePages) ||
144 !FLAG_IS_DEFAULT(LargePageSizeInBytes))) {
145 log_debug(gc, heap, coops)("Reserve regular memory without large pages");
146 }
147 }
148 }
149
150 if (base == NULL) {
151 // Optimistically assume that the OSes returns an aligned base pointer.
152 // When reserving a large address range, most OSes seem to align to at
153 // least 64K.
154
155 // If the memory was requested at a particular address, use
156 // os::attempt_reserve_memory_at() to avoid over mapping something
157 // important. If available space is not detected, return NULL.
158
159 if (requested_address != 0) {
160 base = os::attempt_reserve_memory_at(size, requested_address);
161 if (failed_to_reserve_as_requested(base, requested_address, size, false)) {
162 // OS ignored requested address. Try different address.
163 base = NULL;
164 }
165 } else {
166 base = os::reserve_memory(size, NULL, alignment);
167 }
168
169 if (base == NULL) return;
170
171 // Check alignment constraints
172 if ((((size_t)base) & (alignment - 1)) != 0) {
173 // Base not aligned, retry
174 if (!os::release_memory(base, size)) fatal("os::release_memory failed");
175 // Make sure that size is aligned
176 size = align_size_up(size, alignment);
177 base = os::reserve_memory_aligned(size, alignment);
178
179 if (requested_address != 0 &&
180 failed_to_reserve_as_requested(base, requested_address, size, false)) {
181 // As a result of the alignment constraints, the allocated base differs
182 // from the requested address. Return back to the caller who can
183 // take remedial action (like try again without a requested address).
184 assert(_base == NULL, "should be");
185 return;
186 }
187 }
188 }
189 // Done
190 _base = base;
191 _size = size;
192 _alignment = alignment;
193 }
194
195
196 ReservedSpace::ReservedSpace(char* base, size_t size, size_t alignment,
197 bool special, bool executable) {
198 assert((size % os::vm_allocation_granularity()) == 0,
199 "size not allocation aligned");
200 _base = base;
201 _size = size;
202 _alignment = alignment;
203 _noaccess_prefix = 0;
204 _special = special;
205 _executable = executable;
206 }
207
208
209 ReservedSpace ReservedSpace::first_part(size_t partition_size, size_t alignment,
210 bool split, bool realloc) {
211 assert(partition_size <= size(), "partition failed");
212 if (split) {
213 os::split_reserved_memory(base(), size(), partition_size, realloc);
214 }
215 ReservedSpace result(base(), partition_size, alignment, special(),
216 executable());
217 return result;
218 }
219
220
221 ReservedSpace
222 ReservedSpace::last_part(size_t partition_size, size_t alignment) {
223 assert(partition_size <= size(), "partition failed");
224 ReservedSpace result(base() + partition_size, size() - partition_size,
225 alignment, special(), executable());
226 return result;
227 }
228
229
230 size_t ReservedSpace::page_align_size_up(size_t size) {
231 return align_size_up(size, os::vm_page_size());
232 }
233
234
235 size_t ReservedSpace::page_align_size_down(size_t size) {
236 return align_size_down(size, os::vm_page_size());
237 }
238
239
240 size_t ReservedSpace::allocation_align_size_up(size_t size) {
241 return align_size_up(size, os::vm_allocation_granularity());
242 }
243
244
245 size_t ReservedSpace::allocation_align_size_down(size_t size) {
246 return align_size_down(size, os::vm_allocation_granularity());
247 }
248
249
250 void ReservedSpace::release() {
251 if (is_reserved()) {
252 char *real_base = _base - _noaccess_prefix;
253 const size_t real_size = _size + _noaccess_prefix;
254 if (special()) {
255 os::release_memory_special(real_base, real_size);
256 } else{
257 os::release_memory(real_base, real_size);
258 }
259 _base = NULL;
260 _size = 0;
261 _noaccess_prefix = 0;
262 _alignment = 0;
263 _special = false;
264 _executable = false;
265 }
266 }
267
268 static size_t noaccess_prefix_size(size_t alignment) {
269 return lcm(os::vm_page_size(), alignment);
270 }
271
272 void ReservedHeapSpace::establish_noaccess_prefix() {
273 assert(_alignment >= (size_t)os::vm_page_size(), "must be at least page size big");
274 _noaccess_prefix = noaccess_prefix_size(_alignment);
275
276 if (base() && base() + _size > (char *)OopEncodingHeapMax) {
277 if (true
278 WIN64_ONLY(&& !UseLargePages)
279 AIX_ONLY(&& os::vm_page_size() != SIZE_64K)) {
280 // Protect memory at the base of the allocated region.
281 // If special, the page was committed (only matters on windows)
282 if (!os::protect_memory(_base, _noaccess_prefix, os::MEM_PROT_NONE, _special)) {
283 fatal("cannot protect protection page");
284 }
285 log_debug(gc, heap, coops)("Protected page at the reserved heap base: "
286 PTR_FORMAT " / " INTX_FORMAT " bytes",
287 p2i(_base),
288 _noaccess_prefix);
289 assert(Universe::narrow_oop_use_implicit_null_checks() == true, "not initialized?");
290 } else {
291 Universe::set_narrow_oop_use_implicit_null_checks(false);
292 }
293 }
294
295 _base += _noaccess_prefix;
296 _size -= _noaccess_prefix;
297 assert(((uintptr_t)_base % _alignment == 0), "must be exactly of required alignment");
298 }
299
300 // Tries to allocate memory of size 'size' at address requested_address with alignment 'alignment'.
301 // Does not check whether the reserved memory actually is at requested_address, as the memory returned
302 // might still fulfill the wishes of the caller.
303 // Assures the memory is aligned to 'alignment'.
304 // NOTE: If ReservedHeapSpace already points to some reserved memory this is freed, first.
305 void ReservedHeapSpace::try_reserve_heap(size_t size,
306 size_t alignment,
307 bool large,
308 char* requested_address) {
309 if (_base != NULL) {
310 // We tried before, but we didn't like the address delivered.
311 release();
312 }
313
314 // If OS doesn't support demand paging for large page memory, we need
315 // to use reserve_memory_special() to reserve and pin the entire region.
316 bool special = large && !os::can_commit_large_page_memory();
317 char* base = NULL;
318
319 log_trace(gc, heap, coops)("Trying to allocate at address " PTR_FORMAT
320 " heap of size " SIZE_FORMAT_HEX,
321 p2i(requested_address),
322 size);
323
324 if (special) {
325 base = os::reserve_memory_special(size, alignment, requested_address, false);
326
327 if (base != NULL) {
328 // Check alignment constraints.
329 assert((uintptr_t) base % alignment == 0,
330 "Large pages returned a non-aligned address, base: "
331 PTR_FORMAT " alignment: " SIZE_FORMAT_HEX,
332 p2i(base), alignment);
333 _special = true;
334 }
335 }
336
337 if (base == NULL) {
338 // Failed; try to reserve regular memory below
339 if (UseLargePages && (!FLAG_IS_DEFAULT(UseLargePages) ||
340 !FLAG_IS_DEFAULT(LargePageSizeInBytes))) {
341 log_debug(gc, heap, coops)("Reserve regular memory without large pages");
342 }
343
344 // Optimistically assume that the OSes returns an aligned base pointer.
345 // When reserving a large address range, most OSes seem to align to at
346 // least 64K.
347
348 // If the memory was requested at a particular address, use
349 // os::attempt_reserve_memory_at() to avoid over mapping something
350 // important. If available space is not detected, return NULL.
351
352 if (requested_address != 0) {
353 base = os::attempt_reserve_memory_at(size, requested_address);
354 } else {
355 base = os::reserve_memory(size, NULL, alignment);
356 }
357 }
358 if (base == NULL) { return; }
359
360 // Done
361 _base = base;
362 _size = size;
363 _alignment = alignment;
364
365 // Check alignment constraints
366 if ((((size_t)base) & (alignment - 1)) != 0) {
367 // Base not aligned, retry.
368 release();
369 }
370 }
371
372 void ReservedHeapSpace::try_reserve_range(char *highest_start,
373 char *lowest_start,
374 size_t attach_point_alignment,
375 char *aligned_heap_base_min_address,
376 char *upper_bound,
377 size_t size,
378 size_t alignment,
379 bool large) {
380 const size_t attach_range = highest_start - lowest_start;
381 // Cap num_attempts at possible number.
382 // At least one is possible even for 0 sized attach range.
383 const uint64_t num_attempts_possible = (attach_range / attach_point_alignment) + 1;
384 const uint64_t num_attempts_to_try = MIN2((uint64_t)HeapSearchSteps, num_attempts_possible);
385
386 const size_t stepsize = (attach_range == 0) ? // Only one try.
387 (size_t) highest_start : align_size_up(attach_range / num_attempts_to_try, attach_point_alignment);
388
389 // Try attach points from top to bottom.
390 char* attach_point = highest_start;
391 while (attach_point >= lowest_start &&
392 attach_point <= highest_start && // Avoid wrap around.
393 ((_base == NULL) ||
394 (_base < aligned_heap_base_min_address || _base + size > upper_bound))) {
395 try_reserve_heap(size, alignment, large, attach_point);
396 attach_point -= stepsize;
397 }
398 }
399
400 #define SIZE_64K ((uint64_t) UCONST64( 0x10000))
401 #define SIZE_256M ((uint64_t) UCONST64( 0x10000000))
402 #define SIZE_32G ((uint64_t) UCONST64( 0x800000000))
403
404 // Helper for heap allocation. Returns an array with addresses
405 // (OS-specific) which are suited for disjoint base mode. Array is
406 // NULL terminated.
407 static char** get_attach_addresses_for_disjoint_mode() {
408 static uint64_t addresses[] = {
409 2 * SIZE_32G,
410 3 * SIZE_32G,
411 4 * SIZE_32G,
412 8 * SIZE_32G,
413 10 * SIZE_32G,
414 1 * SIZE_64K * SIZE_32G,
415 2 * SIZE_64K * SIZE_32G,
416 3 * SIZE_64K * SIZE_32G,
417 4 * SIZE_64K * SIZE_32G,
418 16 * SIZE_64K * SIZE_32G,
419 32 * SIZE_64K * SIZE_32G,
420 34 * SIZE_64K * SIZE_32G,
421 0
422 };
423
424 // Sort out addresses smaller than HeapBaseMinAddress. This assumes
425 // the array is sorted.
426 uint i = 0;
427 while (addresses[i] != 0 &&
428 (addresses[i] < OopEncodingHeapMax || addresses[i] < HeapBaseMinAddress)) {
429 i++;
430 }
431 uint start = i;
432
433 // Avoid more steps than requested.
434 i = 0;
435 while (addresses[start+i] != 0) {
436 if (i == HeapSearchSteps) {
437 addresses[start+i] = 0;
438 break;
439 }
440 i++;
441 }
442
443 return (char**) &addresses[start];
444 }
445
446 void ReservedHeapSpace::initialize_compressed_heap(const size_t size, size_t alignment, bool large) {
447 guarantee(size + noaccess_prefix_size(alignment) <= OopEncodingHeapMax,
448 "can not allocate compressed oop heap for this size");
449 guarantee(alignment == MAX2(alignment, (size_t)os::vm_page_size()), "alignment too small");
450 assert(HeapBaseMinAddress > 0, "sanity");
451
452 const size_t granularity = os::vm_allocation_granularity();
453 assert((size & (granularity - 1)) == 0,
454 "size not aligned to os::vm_allocation_granularity()");
455 assert((alignment & (granularity - 1)) == 0,
456 "alignment not aligned to os::vm_allocation_granularity()");
457 assert(alignment == 0 || is_power_of_2((intptr_t)alignment),
458 "not a power of 2");
459
460 // The necessary attach point alignment for generated wish addresses.
461 // This is needed to increase the chance of attaching for mmap and shmat.
462 const size_t os_attach_point_alignment =
463 AIX_ONLY(SIZE_256M) // Known shm boundary alignment.
464 NOT_AIX(os::vm_allocation_granularity());
465 const size_t attach_point_alignment = lcm(alignment, os_attach_point_alignment);
466
467 char *aligned_heap_base_min_address = (char *)align_ptr_up((void *)HeapBaseMinAddress, alignment);
468 size_t noaccess_prefix = ((aligned_heap_base_min_address + size) > (char*)OopEncodingHeapMax) ?
469 noaccess_prefix_size(alignment) : 0;
470
471 // Attempt to alloc at user-given address.
472 if (!FLAG_IS_DEFAULT(HeapBaseMinAddress)) {
473 try_reserve_heap(size + noaccess_prefix, alignment, large, aligned_heap_base_min_address);
474 if (_base != aligned_heap_base_min_address) { // Enforce this exact address.
475 release();
476 }
477 }
478
479 // Keep heap at HeapBaseMinAddress.
480 if (_base == NULL) {
481
482 // Try to allocate the heap at addresses that allow efficient oop compression.
483 // Different schemes are tried, in order of decreasing optimization potential.
484 //
485 // For this, try_reserve_heap() is called with the desired heap base addresses.
486 // A call into the os layer to allocate at a given address can return memory
487 // at a different address than requested. Still, this might be memory at a useful
488 // address. try_reserve_heap() always returns this allocated memory, as only here
489 // the criteria for a good heap are checked.
490
491 // Attempt to allocate so that we can run without base and scale (32-Bit unscaled compressed oops).
492 // Give it several tries from top of range to bottom.
493 if (aligned_heap_base_min_address + size <= (char *)UnscaledOopHeapMax) {
494
495 // Calc address range within we try to attach (range of possible start addresses).
496 char* const highest_start = (char *)align_ptr_down((char *)UnscaledOopHeapMax - size, attach_point_alignment);
497 char* const lowest_start = (char *)align_ptr_up(aligned_heap_base_min_address, attach_point_alignment);
498 try_reserve_range(highest_start, lowest_start, attach_point_alignment,
499 aligned_heap_base_min_address, (char *)UnscaledOopHeapMax, size, alignment, large);
500 }
501
502 // zerobased: Attempt to allocate in the lower 32G.
503 // But leave room for the compressed class pointers, which is allocated above
504 // the heap.
505 char *zerobased_max = (char *)OopEncodingHeapMax;
506 const size_t class_space = align_size_up(CompressedClassSpaceSize, alignment);
507 // For small heaps, save some space for compressed class pointer
508 // space so it can be decoded with no base.
509 if (UseCompressedClassPointers && !UseSharedSpaces &&
510 OopEncodingHeapMax <= KlassEncodingMetaspaceMax &&
511 (uint64_t)(aligned_heap_base_min_address + size + class_space) <= KlassEncodingMetaspaceMax) {
512 zerobased_max = (char *)OopEncodingHeapMax - class_space;
513 }
514
515 // Give it several tries from top of range to bottom.
516 if (aligned_heap_base_min_address + size <= zerobased_max && // Zerobased theoretical possible.
517 ((_base == NULL) || // No previous try succeeded.
518 (_base + size > zerobased_max))) { // Unscaled delivered an arbitrary address.
519
520 // Calc address range within we try to attach (range of possible start addresses).
521 char *const highest_start = (char *)align_ptr_down(zerobased_max - size, attach_point_alignment);
522 // Need to be careful about size being guaranteed to be less
523 // than UnscaledOopHeapMax due to type constraints.
524 char *lowest_start = aligned_heap_base_min_address;
525 uint64_t unscaled_end = UnscaledOopHeapMax - size;
526 if (unscaled_end < UnscaledOopHeapMax) { // unscaled_end wrapped if size is large
527 lowest_start = MAX2(lowest_start, (char*)unscaled_end);
528 }
529 lowest_start = (char *)align_ptr_up(lowest_start, attach_point_alignment);
530 try_reserve_range(highest_start, lowest_start, attach_point_alignment,
531 aligned_heap_base_min_address, zerobased_max, size, alignment, large);
532 }
533
534 // Now we go for heaps with base != 0. We need a noaccess prefix to efficiently
535 // implement null checks.
536 noaccess_prefix = noaccess_prefix_size(alignment);
537
538 // Try to attach at addresses that are aligned to OopEncodingHeapMax. Disjointbase mode.
539 char** addresses = get_attach_addresses_for_disjoint_mode();
540 int i = 0;
541 while (addresses[i] && // End of array not yet reached.
542 ((_base == NULL) || // No previous try succeeded.
543 (_base + size > (char *)OopEncodingHeapMax && // Not zerobased or unscaled address.
544 !Universe::is_disjoint_heap_base_address((address)_base)))) { // Not disjoint address.
545 char* const attach_point = addresses[i];
546 assert(attach_point >= aligned_heap_base_min_address, "Flag support broken");
547 try_reserve_heap(size + noaccess_prefix, alignment, large, attach_point);
548 i++;
549 }
550
551 // Last, desperate try without any placement.
552 if (_base == NULL) {
553 log_trace(gc, heap, coops)("Trying to allocate at address NULL heap of size " SIZE_FORMAT_HEX, size + noaccess_prefix);
554 initialize(size + noaccess_prefix, alignment, large, NULL, false);
555 }
556 }
557 }
558
559 ReservedHeapSpace::ReservedHeapSpace(size_t size, size_t alignment, bool large) : ReservedSpace() {
560
561 if (size == 0) {
562 return;
563 }
564
565 // Heap size should be aligned to alignment, too.
566 guarantee(is_size_aligned(size, alignment), "set by caller");
567
568 if (UseCompressedOops) {
569 initialize_compressed_heap(size, alignment, large);
570 if (_size > size) {
571 // We allocated heap with noaccess prefix.
572 // It can happen we get a zerobased/unscaled heap with noaccess prefix,
573 // if we had to try at arbitrary address.
574 establish_noaccess_prefix();
575 }
576 } else {
577 initialize(size, alignment, large, NULL, false);
578 }
579
580 assert(markOopDesc::encode_pointer_as_mark(_base)->decode_pointer() == _base,
581 "area must be distinguishable from marks for mark-sweep");
582 assert(markOopDesc::encode_pointer_as_mark(&_base[size])->decode_pointer() == &_base[size],
583 "area must be distinguishable from marks for mark-sweep");
584
585 if (base() > 0) {
586 MemTracker::record_virtual_memory_type((address)base(), mtJavaHeap);
587 }
588 }
589
590 // Reserve space for code segment. Same as Java heap only we mark this as
591 // executable.
592 ReservedCodeSpace::ReservedCodeSpace(size_t r_size,
593 size_t rs_align,
594 bool large) :
595 ReservedSpace(r_size, rs_align, large, /*executable*/ CodeCacheExtensions::support_dynamic_code()) {
596 MemTracker::record_virtual_memory_type((address)base(), mtCode);
597 }
598
599 // VirtualSpace
600
601 VirtualSpace::VirtualSpace() {
602 _low_boundary = NULL;
603 _high_boundary = NULL;
604 _low = NULL;
605 _high = NULL;
606 _lower_high = NULL;
607 _middle_high = NULL;
608 _upper_high = NULL;
609 _lower_high_boundary = NULL;
610 _middle_high_boundary = NULL;
611 _upper_high_boundary = NULL;
612 _lower_alignment = 0;
613 _middle_alignment = 0;
614 _upper_alignment = 0;
615 _special = false;
616 _executable = false;
617 }
618
619
620 bool VirtualSpace::initialize(ReservedSpace rs, size_t committed_size) {
621 const size_t max_commit_granularity = os::page_size_for_region_unaligned(rs.size(), 1);
622 return initialize_with_granularity(rs, committed_size, max_commit_granularity);
623 }
624
625 bool VirtualSpace::initialize_with_granularity(ReservedSpace rs, size_t committed_size, size_t max_commit_granularity) {
626 if(!rs.is_reserved()) return false; // allocation failed.
627 assert(_low_boundary == NULL, "VirtualSpace already initialized");
628 assert(max_commit_granularity > 0, "Granularity must be non-zero.");
629
630 _low_boundary = rs.base();
631 _high_boundary = low_boundary() + rs.size();
632
633 _low = low_boundary();
634 _high = low();
635
636 _special = rs.special();
637 _executable = rs.executable();
638
639 // When a VirtualSpace begins life at a large size, make all future expansion
640 // and shrinking occur aligned to a granularity of large pages. This avoids
641 // fragmentation of physical addresses that inhibits the use of large pages
642 // by the OS virtual memory system. Empirically, we see that with a 4MB
643 // page size, the only spaces that get handled this way are codecache and
644 // the heap itself, both of which provide a substantial performance
645 // boost in many benchmarks when covered by large pages.
646 //
647 // No attempt is made to force large page alignment at the very top and
648 // bottom of the space if they are not aligned so already.
649 _lower_alignment = os::vm_page_size();
650 _middle_alignment = max_commit_granularity;
651 _upper_alignment = os::vm_page_size();
652
653 // End of each region
654 _lower_high_boundary = (char*) round_to((intptr_t) low_boundary(), middle_alignment());
655 _middle_high_boundary = (char*) round_down((intptr_t) high_boundary(), middle_alignment());
656 _upper_high_boundary = high_boundary();
657
658 // High address of each region
659 _lower_high = low_boundary();
660 _middle_high = lower_high_boundary();
661 _upper_high = middle_high_boundary();
662
663 // commit to initial size
664 if (committed_size > 0) {
665 if (!expand_by(committed_size)) {
666 return false;
667 }
668 }
669 return true;
670 }
671
672
673 VirtualSpace::~VirtualSpace() {
674 release();
675 }
676
677
678 void VirtualSpace::release() {
679 // This does not release memory it never reserved.
680 // Caller must release via rs.release();
681 _low_boundary = NULL;
682 _high_boundary = NULL;
683 _low = NULL;
684 _high = NULL;
685 _lower_high = NULL;
686 _middle_high = NULL;
687 _upper_high = NULL;
688 _lower_high_boundary = NULL;
689 _middle_high_boundary = NULL;
690 _upper_high_boundary = NULL;
691 _lower_alignment = 0;
692 _middle_alignment = 0;
693 _upper_alignment = 0;
694 _special = false;
695 _executable = false;
696 }
697
698
699 size_t VirtualSpace::committed_size() const {
700 return pointer_delta(high(), low(), sizeof(char));
701 }
702
703
704 size_t VirtualSpace::reserved_size() const {
705 return pointer_delta(high_boundary(), low_boundary(), sizeof(char));
706 }
707
708
709 size_t VirtualSpace::uncommitted_size() const {
710 return reserved_size() - committed_size();
711 }
712
713 size_t VirtualSpace::actual_committed_size() const {
714 // Special VirtualSpaces commit all reserved space up front.
715 if (special()) {
716 return reserved_size();
717 }
718
719 size_t committed_low = pointer_delta(_lower_high, _low_boundary, sizeof(char));
720 size_t committed_middle = pointer_delta(_middle_high, _lower_high_boundary, sizeof(char));
721 size_t committed_high = pointer_delta(_upper_high, _middle_high_boundary, sizeof(char));
722
723 #ifdef ASSERT
724 size_t lower = pointer_delta(_lower_high_boundary, _low_boundary, sizeof(char));
725 size_t middle = pointer_delta(_middle_high_boundary, _lower_high_boundary, sizeof(char));
726 size_t upper = pointer_delta(_upper_high_boundary, _middle_high_boundary, sizeof(char));
727
728 if (committed_high > 0) {
729 assert(committed_low == lower, "Must be");
730 assert(committed_middle == middle, "Must be");
731 }
732
733 if (committed_middle > 0) {
734 assert(committed_low == lower, "Must be");
735 }
736 if (committed_middle < middle) {
737 assert(committed_high == 0, "Must be");
738 }
739
740 if (committed_low < lower) {
741 assert(committed_high == 0, "Must be");
742 assert(committed_middle == 0, "Must be");
743 }
744 #endif
745
746 return committed_low + committed_middle + committed_high;
747 }
748
749
750 bool VirtualSpace::contains(const void* p) const {
751 return low() <= (const char*) p && (const char*) p < high();
752 }
753
754 /*
755 First we need to determine if a particular virtual space is using large
756 pages. This is done at the initialize function and only virtual spaces
757 that are larger than LargePageSizeInBytes use large pages. Once we
758 have determined this, all expand_by and shrink_by calls must grow and
759 shrink by large page size chunks. If a particular request
760 is within the current large page, the call to commit and uncommit memory
761 can be ignored. In the case that the low and high boundaries of this
762 space is not large page aligned, the pages leading to the first large
763 page address and the pages after the last large page address must be
764 allocated with default pages.
765 */
766 bool VirtualSpace::expand_by(size_t bytes, bool pre_touch) {
767 if (uncommitted_size() < bytes) return false;
768
769 if (special()) {
770 // don't commit memory if the entire space is pinned in memory
771 _high += bytes;
772 return true;
773 }
774
775 char* previous_high = high();
776 char* unaligned_new_high = high() + bytes;
777 assert(unaligned_new_high <= high_boundary(),
778 "cannot expand by more than upper boundary");
779
780 // Calculate where the new high for each of the regions should be. If
781 // the low_boundary() and high_boundary() are LargePageSizeInBytes aligned
782 // then the unaligned lower and upper new highs would be the
783 // lower_high() and upper_high() respectively.
784 char* unaligned_lower_new_high =
785 MIN2(unaligned_new_high, lower_high_boundary());
786 char* unaligned_middle_new_high =
787 MIN2(unaligned_new_high, middle_high_boundary());
788 char* unaligned_upper_new_high =
789 MIN2(unaligned_new_high, upper_high_boundary());
790
791 // Align the new highs based on the regions alignment. lower and upper
792 // alignment will always be default page size. middle alignment will be
793 // LargePageSizeInBytes if the actual size of the virtual space is in
794 // fact larger than LargePageSizeInBytes.
795 char* aligned_lower_new_high =
796 (char*) round_to((intptr_t) unaligned_lower_new_high, lower_alignment());
797 char* aligned_middle_new_high =
798 (char*) round_to((intptr_t) unaligned_middle_new_high, middle_alignment());
799 char* aligned_upper_new_high =
800 (char*) round_to((intptr_t) unaligned_upper_new_high, upper_alignment());
801
802 // Determine which regions need to grow in this expand_by call.
803 // If you are growing in the lower region, high() must be in that
804 // region so calculate the size based on high(). For the middle and
805 // upper regions, determine the starting point of growth based on the
806 // location of high(). By getting the MAX of the region's low address
807 // (or the previous region's high address) and high(), we can tell if it
808 // is an intra or inter region growth.
809 size_t lower_needs = 0;
810 if (aligned_lower_new_high > lower_high()) {
811 lower_needs =
812 pointer_delta(aligned_lower_new_high, lower_high(), sizeof(char));
813 }
814 size_t middle_needs = 0;
815 if (aligned_middle_new_high > middle_high()) {
816 middle_needs =
817 pointer_delta(aligned_middle_new_high, middle_high(), sizeof(char));
818 }
819 size_t upper_needs = 0;
820 if (aligned_upper_new_high > upper_high()) {
821 upper_needs =
822 pointer_delta(aligned_upper_new_high, upper_high(), sizeof(char));
823 }
824
825 // Check contiguity.
826 assert(low_boundary() <= lower_high() &&
827 lower_high() <= lower_high_boundary(),
828 "high address must be contained within the region");
829 assert(lower_high_boundary() <= middle_high() &&
830 middle_high() <= middle_high_boundary(),
831 "high address must be contained within the region");
832 assert(middle_high_boundary() <= upper_high() &&
833 upper_high() <= upper_high_boundary(),
834 "high address must be contained within the region");
835
836 // Commit regions
837 if (lower_needs > 0) {
838 assert(low_boundary() <= lower_high() &&
839 lower_high() + lower_needs <= lower_high_boundary(),
840 "must not expand beyond region");
841 if (!os::commit_memory(lower_high(), lower_needs, _executable)) {
842 debug_only(warning("INFO: os::commit_memory(" PTR_FORMAT
843 ", lower_needs=" SIZE_FORMAT ", %d) failed",
844 p2i(lower_high()), lower_needs, _executable);)
845 return false;
846 } else {
847 _lower_high += lower_needs;
848 }
849 }
850 if (middle_needs > 0) {
851 assert(lower_high_boundary() <= middle_high() &&
852 middle_high() + middle_needs <= middle_high_boundary(),
853 "must not expand beyond region");
854 if (!os::commit_memory(middle_high(), middle_needs, middle_alignment(),
855 _executable)) {
856 debug_only(warning("INFO: os::commit_memory(" PTR_FORMAT
857 ", middle_needs=" SIZE_FORMAT ", " SIZE_FORMAT
858 ", %d) failed", p2i(middle_high()), middle_needs,
859 middle_alignment(), _executable);)
860 return false;
861 }
862 _middle_high += middle_needs;
863 }
864 if (upper_needs > 0) {
865 assert(middle_high_boundary() <= upper_high() &&
866 upper_high() + upper_needs <= upper_high_boundary(),
867 "must not expand beyond region");
868 if (!os::commit_memory(upper_high(), upper_needs, _executable)) {
869 debug_only(warning("INFO: os::commit_memory(" PTR_FORMAT
870 ", upper_needs=" SIZE_FORMAT ", %d) failed",
871 p2i(upper_high()), upper_needs, _executable);)
872 return false;
873 } else {
874 _upper_high += upper_needs;
875 }
876 }
877
878 if (pre_touch || AlwaysPreTouch) {
879 os::pretouch_memory(previous_high, unaligned_new_high);
880 }
881
882 _high += bytes;
883 return true;
884 }
885
886 // A page is uncommitted if the contents of the entire page is deemed unusable.
887 // Continue to decrement the high() pointer until it reaches a page boundary
888 // in which case that particular page can now be uncommitted.
889 void VirtualSpace::shrink_by(size_t size) {
890 if (committed_size() < size)
891 fatal("Cannot shrink virtual space to negative size");
892
893 if (special()) {
894 // don't uncommit if the entire space is pinned in memory
895 _high -= size;
896 return;
897 }
898
899 char* unaligned_new_high = high() - size;
900 assert(unaligned_new_high >= low_boundary(), "cannot shrink past lower boundary");
901
902 // Calculate new unaligned address
903 char* unaligned_upper_new_high =
904 MAX2(unaligned_new_high, middle_high_boundary());
905 char* unaligned_middle_new_high =
906 MAX2(unaligned_new_high, lower_high_boundary());
907 char* unaligned_lower_new_high =
908 MAX2(unaligned_new_high, low_boundary());
909
910 // Align address to region's alignment
911 char* aligned_upper_new_high =
912 (char*) round_to((intptr_t) unaligned_upper_new_high, upper_alignment());
913 char* aligned_middle_new_high =
914 (char*) round_to((intptr_t) unaligned_middle_new_high, middle_alignment());
915 char* aligned_lower_new_high =
916 (char*) round_to((intptr_t) unaligned_lower_new_high, lower_alignment());
917
918 // Determine which regions need to shrink
919 size_t upper_needs = 0;
920 if (aligned_upper_new_high < upper_high()) {
921 upper_needs =
922 pointer_delta(upper_high(), aligned_upper_new_high, sizeof(char));
923 }
924 size_t middle_needs = 0;
925 if (aligned_middle_new_high < middle_high()) {
926 middle_needs =
927 pointer_delta(middle_high(), aligned_middle_new_high, sizeof(char));
928 }
929 size_t lower_needs = 0;
930 if (aligned_lower_new_high < lower_high()) {
931 lower_needs =
932 pointer_delta(lower_high(), aligned_lower_new_high, sizeof(char));
933 }
934
935 // Check contiguity.
936 assert(middle_high_boundary() <= upper_high() &&
937 upper_high() <= upper_high_boundary(),
938 "high address must be contained within the region");
939 assert(lower_high_boundary() <= middle_high() &&
940 middle_high() <= middle_high_boundary(),
941 "high address must be contained within the region");
942 assert(low_boundary() <= lower_high() &&
943 lower_high() <= lower_high_boundary(),
944 "high address must be contained within the region");
945
946 // Uncommit
947 if (upper_needs > 0) {
948 assert(middle_high_boundary() <= aligned_upper_new_high &&
949 aligned_upper_new_high + upper_needs <= upper_high_boundary(),
950 "must not shrink beyond region");
951 if (!os::uncommit_memory(aligned_upper_new_high, upper_needs)) {
952 debug_only(warning("os::uncommit_memory failed"));
953 return;
954 } else {
955 _upper_high -= upper_needs;
956 }
957 }
958 if (middle_needs > 0) {
959 assert(lower_high_boundary() <= aligned_middle_new_high &&
960 aligned_middle_new_high + middle_needs <= middle_high_boundary(),
961 "must not shrink beyond region");
962 if (!os::uncommit_memory(aligned_middle_new_high, middle_needs)) {
963 debug_only(warning("os::uncommit_memory failed"));
964 return;
965 } else {
966 _middle_high -= middle_needs;
967 }
968 }
969 if (lower_needs > 0) {
970 assert(low_boundary() <= aligned_lower_new_high &&
971 aligned_lower_new_high + lower_needs <= lower_high_boundary(),
972 "must not shrink beyond region");
973 if (!os::uncommit_memory(aligned_lower_new_high, lower_needs)) {
974 debug_only(warning("os::uncommit_memory failed"));
975 return;
976 } else {
977 _lower_high -= lower_needs;
978 }
979 }
980
981 _high -= size;
982 }
983
984 #ifndef PRODUCT
985 void VirtualSpace::check_for_contiguity() {
986 // Check contiguity.
987 assert(low_boundary() <= lower_high() &&
988 lower_high() <= lower_high_boundary(),
989 "high address must be contained within the region");
990 assert(lower_high_boundary() <= middle_high() &&
991 middle_high() <= middle_high_boundary(),
992 "high address must be contained within the region");
993 assert(middle_high_boundary() <= upper_high() &&
994 upper_high() <= upper_high_boundary(),
995 "high address must be contained within the region");
996 assert(low() >= low_boundary(), "low");
997 assert(low_boundary() <= lower_high_boundary(), "lower high boundary");
998 assert(upper_high_boundary() <= high_boundary(), "upper high boundary");
999 assert(high() <= upper_high(), "upper high");
1000 }
1001
1002 void VirtualSpace::print_on(outputStream* out) {
1003 out->print ("Virtual space:");
1004 if (special()) out->print(" (pinned in memory)");
1005 out->cr();
1006 out->print_cr(" - committed: " SIZE_FORMAT, committed_size());
1007 out->print_cr(" - reserved: " SIZE_FORMAT, reserved_size());
1008 out->print_cr(" - [low, high]: [" INTPTR_FORMAT ", " INTPTR_FORMAT "]", p2i(low()), p2i(high()));
1009 out->print_cr(" - [low_b, high_b]: [" INTPTR_FORMAT ", " INTPTR_FORMAT "]", p2i(low_boundary()), p2i(high_boundary()));
1010 }
1011
1012 void VirtualSpace::print() {
1013 print_on(tty);
1014 }
1015
1016 /////////////// Unit tests ///////////////
1017
1018 #ifndef PRODUCT
1019
1020 #define test_log(...) \
1021 do {\
1022 if (VerboseInternalVMTests) { \
1023 tty->print_cr(__VA_ARGS__); \
1024 tty->flush(); \
1025 }\
1026 } while (false)
1027
1028 class TestReservedSpace : AllStatic {
1029 public:
1030 static void small_page_write(void* addr, size_t size) {
1031 size_t page_size = os::vm_page_size();
1032
1033 char* end = (char*)addr + size;
1034 for (char* p = (char*)addr; p < end; p += page_size) {
1035 *p = 1;
1036 }
1037 }
1038
1039 static void release_memory_for_test(ReservedSpace rs) {
1040 if (rs.special()) {
1041 guarantee(os::release_memory_special(rs.base(), rs.size()), "Shouldn't fail");
1042 } else {
1043 guarantee(os::release_memory(rs.base(), rs.size()), "Shouldn't fail");
1044 }
1045 }
1046
1047 static void test_reserved_space1(size_t size, size_t alignment) {
1048 test_log("test_reserved_space1(%p)", (void*) (uintptr_t) size);
1049
1050 assert(is_size_aligned(size, alignment), "Incorrect input parameters");
1051
1052 ReservedSpace rs(size, // size
1053 alignment, // alignment
1054 UseLargePages, // large
1055 (char *)NULL); // requested_address
1056
1057 test_log(" rs.special() == %d", rs.special());
1058
1059 assert(rs.base() != NULL, "Must be");
1060 assert(rs.size() == size, "Must be");
1061
1062 assert(is_ptr_aligned(rs.base(), alignment), "aligned sizes should always give aligned addresses");
1063 assert(is_size_aligned(rs.size(), alignment), "aligned sizes should always give aligned addresses");
1064
1065 if (rs.special()) {
1066 small_page_write(rs.base(), size);
1067 }
1068
1069 release_memory_for_test(rs);
1070 }
1071
1072 static void test_reserved_space2(size_t size) {
1073 test_log("test_reserved_space2(%p)", (void*)(uintptr_t)size);
1074
1075 assert(is_size_aligned(size, os::vm_allocation_granularity()), "Must be at least AG aligned");
1076
1077 ReservedSpace rs(size);
1078
1079 test_log(" rs.special() == %d", rs.special());
1080
1081 assert(rs.base() != NULL, "Must be");
1082 assert(rs.size() == size, "Must be");
1083
1084 if (rs.special()) {
1085 small_page_write(rs.base(), size);
1086 }
1087
1088 release_memory_for_test(rs);
1089 }
1090
1091 static void test_reserved_space3(size_t size, size_t alignment, bool maybe_large) {
1092 test_log("test_reserved_space3(%p, %p, %d)",
1093 (void*)(uintptr_t)size, (void*)(uintptr_t)alignment, maybe_large);
1094
1095 if (size < alignment) {
1096 // Tests might set -XX:LargePageSizeInBytes=<small pages> and cause unexpected input arguments for this test.
1097 assert((size_t)os::vm_page_size() == os::large_page_size(), "Test needs further refinement");
1098 return;
1099 }
1100
1101 assert(is_size_aligned(size, os::vm_allocation_granularity()), "Must be at least AG aligned");
1102 assert(is_size_aligned(size, alignment), "Must be at least aligned against alignment");
1103
1104 bool large = maybe_large && UseLargePages && size >= os::large_page_size();
1105
1106 ReservedSpace rs(size, alignment, large, false);
1107
1108 test_log(" rs.special() == %d", rs.special());
1109
1110 assert(rs.base() != NULL, "Must be");
1111 assert(rs.size() == size, "Must be");
1112
1113 if (rs.special()) {
1114 small_page_write(rs.base(), size);
1115 }
1116
1117 release_memory_for_test(rs);
1118 }
1119
1120
1121 static void test_reserved_space1() {
1122 size_t size = 2 * 1024 * 1024;
1123 size_t ag = os::vm_allocation_granularity();
1124
1125 test_reserved_space1(size, ag);
1126 test_reserved_space1(size * 2, ag);
1127 test_reserved_space1(size * 10, ag);
1128 }
1129
1130 static void test_reserved_space2() {
1131 size_t size = 2 * 1024 * 1024;
1132 size_t ag = os::vm_allocation_granularity();
1133
1134 test_reserved_space2(size * 1);
1135 test_reserved_space2(size * 2);
1136 test_reserved_space2(size * 10);
1137 test_reserved_space2(ag);
1138 test_reserved_space2(size - ag);
1139 test_reserved_space2(size);
1140 test_reserved_space2(size + ag);
1141 test_reserved_space2(size * 2);
1142 test_reserved_space2(size * 2 - ag);
1143 test_reserved_space2(size * 2 + ag);
1144 test_reserved_space2(size * 3);
1145 test_reserved_space2(size * 3 - ag);
1146 test_reserved_space2(size * 3 + ag);
1147 test_reserved_space2(size * 10);
1148 test_reserved_space2(size * 10 + size / 2);
1149 }
1150
1151 static void test_reserved_space3() {
1152 size_t ag = os::vm_allocation_granularity();
1153
1154 test_reserved_space3(ag, ag , false);
1155 test_reserved_space3(ag * 2, ag , false);
1156 test_reserved_space3(ag * 3, ag , false);
1157 test_reserved_space3(ag * 2, ag * 2, false);
1158 test_reserved_space3(ag * 4, ag * 2, false);
1159 test_reserved_space3(ag * 8, ag * 2, false);
1160 test_reserved_space3(ag * 4, ag * 4, false);
1161 test_reserved_space3(ag * 8, ag * 4, false);
1162 test_reserved_space3(ag * 16, ag * 4, false);
1163
1164 if (UseLargePages) {
1165 size_t lp = os::large_page_size();
1166
1167 // Without large pages
1168 test_reserved_space3(lp, ag * 4, false);
1169 test_reserved_space3(lp * 2, ag * 4, false);
1170 test_reserved_space3(lp * 4, ag * 4, false);
1171 test_reserved_space3(lp, lp , false);
1172 test_reserved_space3(lp * 2, lp , false);
1173 test_reserved_space3(lp * 3, lp , false);
1174 test_reserved_space3(lp * 2, lp * 2, false);
1175 test_reserved_space3(lp * 4, lp * 2, false);
1176 test_reserved_space3(lp * 8, lp * 2, false);
1177
1178 // With large pages
1179 test_reserved_space3(lp, ag * 4 , true);
1180 test_reserved_space3(lp * 2, ag * 4, true);
1181 test_reserved_space3(lp * 4, ag * 4, true);
1182 test_reserved_space3(lp, lp , true);
1183 test_reserved_space3(lp * 2, lp , true);
1184 test_reserved_space3(lp * 3, lp , true);
1185 test_reserved_space3(lp * 2, lp * 2, true);
1186 test_reserved_space3(lp * 4, lp * 2, true);
1187 test_reserved_space3(lp * 8, lp * 2, true);
1188 }
1189 }
1190
1191 static void test_reserved_space() {
1192 test_reserved_space1();
1193 test_reserved_space2();
1194 test_reserved_space3();
1195 }
1196 };
1197
1198 void TestReservedSpace_test() {
1199 TestReservedSpace::test_reserved_space();
1200 }
1201
1202 #define assert_equals(actual, expected) \
1203 assert(actual == expected, \
1204 "Got " SIZE_FORMAT " expected " \
1205 SIZE_FORMAT, actual, expected);
1206
1207 #define assert_ge(value1, value2) \
1208 assert(value1 >= value2, \
1209 "'" #value1 "': " SIZE_FORMAT " '" \
1210 #value2 "': " SIZE_FORMAT, value1, value2);
1211
1212 #define assert_lt(value1, value2) \
1213 assert(value1 < value2, \
1214 "'" #value1 "': " SIZE_FORMAT " '" \
1215 #value2 "': " SIZE_FORMAT, value1, value2);
1216
1217
1218 class TestVirtualSpace : AllStatic {
1219 enum TestLargePages {
1220 Default,
1221 Disable,
1222 Reserve,
1223 Commit
1224 };
1225
1226 static ReservedSpace reserve_memory(size_t reserve_size_aligned, TestLargePages mode) {
1227 switch(mode) {
1228 default:
1229 case Default:
1230 case Reserve:
1231 return ReservedSpace(reserve_size_aligned);
1232 case Disable:
1233 case Commit:
1234 return ReservedSpace(reserve_size_aligned,
1235 os::vm_allocation_granularity(),
1236 /* large */ false, /* exec */ false);
1237 }
1238 }
1239
1240 static bool initialize_virtual_space(VirtualSpace& vs, ReservedSpace rs, TestLargePages mode) {
1241 switch(mode) {
1242 default:
1243 case Default:
1244 case Reserve:
1245 return vs.initialize(rs, 0);
1246 case Disable:
1247 return vs.initialize_with_granularity(rs, 0, os::vm_page_size());
1248 case Commit:
1249 return vs.initialize_with_granularity(rs, 0, os::page_size_for_region_unaligned(rs.size(), 1));
1250 }
1251 }
1252
1253 public:
1254 static void test_virtual_space_actual_committed_space(size_t reserve_size, size_t commit_size,
1255 TestLargePages mode = Default) {
1256 size_t granularity = os::vm_allocation_granularity();
1257 size_t reserve_size_aligned = align_size_up(reserve_size, granularity);
1258
1259 ReservedSpace reserved = reserve_memory(reserve_size_aligned, mode);
1260
1261 assert(reserved.is_reserved(), "Must be");
1262
1263 VirtualSpace vs;
1264 bool initialized = initialize_virtual_space(vs, reserved, mode);
1265 assert(initialized, "Failed to initialize VirtualSpace");
1266
1267 vs.expand_by(commit_size, false);
1268
1269 if (vs.special()) {
1270 assert_equals(vs.actual_committed_size(), reserve_size_aligned);
1271 } else {
1272 assert_ge(vs.actual_committed_size(), commit_size);
1273 // Approximate the commit granularity.
1274 // Make sure that we don't commit using large pages
1275 // if large pages has been disabled for this VirtualSpace.
1276 size_t commit_granularity = (mode == Disable || !UseLargePages) ?
1277 os::vm_page_size() : os::large_page_size();
1278 assert_lt(vs.actual_committed_size(), commit_size + commit_granularity);
1279 }
1280
1281 reserved.release();
1282 }
1283
1284 static void test_virtual_space_actual_committed_space_one_large_page() {
1285 if (!UseLargePages) {
1286 return;
1287 }
1288
1289 size_t large_page_size = os::large_page_size();
1290
1291 ReservedSpace reserved(large_page_size, large_page_size, true, false);
1292
1293 assert(reserved.is_reserved(), "Must be");
1294
1295 VirtualSpace vs;
1296 bool initialized = vs.initialize(reserved, 0);
1297 assert(initialized, "Failed to initialize VirtualSpace");
1298
1299 vs.expand_by(large_page_size, false);
1300
1301 assert_equals(vs.actual_committed_size(), large_page_size);
1302
1303 reserved.release();
1304 }
1305
1306 static void test_virtual_space_actual_committed_space() {
1307 test_virtual_space_actual_committed_space(4 * K, 0);
1308 test_virtual_space_actual_committed_space(4 * K, 4 * K);
1309 test_virtual_space_actual_committed_space(8 * K, 0);
1310 test_virtual_space_actual_committed_space(8 * K, 4 * K);
1311 test_virtual_space_actual_committed_space(8 * K, 8 * K);
1312 test_virtual_space_actual_committed_space(12 * K, 0);
1313 test_virtual_space_actual_committed_space(12 * K, 4 * K);
1314 test_virtual_space_actual_committed_space(12 * K, 8 * K);
1315 test_virtual_space_actual_committed_space(12 * K, 12 * K);
1316 test_virtual_space_actual_committed_space(64 * K, 0);
1317 test_virtual_space_actual_committed_space(64 * K, 32 * K);
1318 test_virtual_space_actual_committed_space(64 * K, 64 * K);
1319 test_virtual_space_actual_committed_space(2 * M, 0);
1320 test_virtual_space_actual_committed_space(2 * M, 4 * K);
1321 test_virtual_space_actual_committed_space(2 * M, 64 * K);
1322 test_virtual_space_actual_committed_space(2 * M, 1 * M);
1323 test_virtual_space_actual_committed_space(2 * M, 2 * M);
1324 test_virtual_space_actual_committed_space(10 * M, 0);
1325 test_virtual_space_actual_committed_space(10 * M, 4 * K);
1326 test_virtual_space_actual_committed_space(10 * M, 8 * K);
1327 test_virtual_space_actual_committed_space(10 * M, 1 * M);
1328 test_virtual_space_actual_committed_space(10 * M, 2 * M);
1329 test_virtual_space_actual_committed_space(10 * M, 5 * M);
1330 test_virtual_space_actual_committed_space(10 * M, 10 * M);
1331 }
1332
1333 static void test_virtual_space_disable_large_pages() {
1334 if (!UseLargePages) {
1335 return;
1336 }
1337 // These test cases verify that if we force VirtualSpace to disable large pages
1338 test_virtual_space_actual_committed_space(10 * M, 0, Disable);
1339 test_virtual_space_actual_committed_space(10 * M, 4 * K, Disable);
1340 test_virtual_space_actual_committed_space(10 * M, 8 * K, Disable);
1341 test_virtual_space_actual_committed_space(10 * M, 1 * M, Disable);
1342 test_virtual_space_actual_committed_space(10 * M, 2 * M, Disable);
1343 test_virtual_space_actual_committed_space(10 * M, 5 * M, Disable);
1344 test_virtual_space_actual_committed_space(10 * M, 10 * M, Disable);
1345
1346 test_virtual_space_actual_committed_space(10 * M, 0, Reserve);
1347 test_virtual_space_actual_committed_space(10 * M, 4 * K, Reserve);
1348 test_virtual_space_actual_committed_space(10 * M, 8 * K, Reserve);
1349 test_virtual_space_actual_committed_space(10 * M, 1 * M, Reserve);
1350 test_virtual_space_actual_committed_space(10 * M, 2 * M, Reserve);
1351 test_virtual_space_actual_committed_space(10 * M, 5 * M, Reserve);
1352 test_virtual_space_actual_committed_space(10 * M, 10 * M, Reserve);
1353
1354 test_virtual_space_actual_committed_space(10 * M, 0, Commit);
1355 test_virtual_space_actual_committed_space(10 * M, 4 * K, Commit);
1356 test_virtual_space_actual_committed_space(10 * M, 8 * K, Commit);
1357 test_virtual_space_actual_committed_space(10 * M, 1 * M, Commit);
1358 test_virtual_space_actual_committed_space(10 * M, 2 * M, Commit);
1359 test_virtual_space_actual_committed_space(10 * M, 5 * M, Commit);
1360 test_virtual_space_actual_committed_space(10 * M, 10 * M, Commit);
1361 }
1362
1363 static void test_virtual_space() {
1364 test_virtual_space_actual_committed_space();
1365 test_virtual_space_actual_committed_space_one_large_page();
1366 test_virtual_space_disable_large_pages();
1367 }
1368 };
1369
1370 void TestVirtualSpace_test() {
1371 TestVirtualSpace::test_virtual_space();
1372 }
1373
1374 #endif // PRODUCT
1375
1376 #endif