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