1 /*
2 * Copyright (c) 1997, 2014, 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 "oops/markOop.hpp"
27 #include "oops/oop.inline.hpp"
28 #include "runtime/virtualspace.hpp"
29 #include "services/memTracker.hpp"
30 #ifdef TARGET_OS_FAMILY_linux
31 # include "os_linux.inline.hpp"
32 #endif
33 #ifdef TARGET_OS_FAMILY_solaris
34 # include "os_solaris.inline.hpp"
35 #endif
36 #ifdef TARGET_OS_FAMILY_windows
37 # include "os_windows.inline.hpp"
38 #endif
39 #ifdef TARGET_OS_FAMILY_aix
40 # include "os_aix.inline.hpp"
41 #endif
42 #ifdef TARGET_OS_FAMILY_bsd
43 # include "os_bsd.inline.hpp"
44 #endif
45
46 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
47
48 // ReservedSpace
49
50 // Dummy constructor
51 ReservedSpace::ReservedSpace() : _base(NULL), _size(0), _noaccess_prefix(0),
52 _alignment(0), _special(false), _executable(false) {
53 }
54
55 ReservedSpace::ReservedSpace(size_t size) {
56 size_t page_size = os::page_size_for_region(size, 1);
57 bool large_pages = page_size != (size_t)os::vm_page_size();
58 // Don't force the alignment to be large page aligned,
59 // since that will waste memory.
60 size_t alignment = os::vm_allocation_granularity();
61 initialize(size, alignment, large_pages, NULL, 0, false);
62 }
63
64 ReservedSpace::ReservedSpace(size_t size, size_t alignment,
65 bool large,
66 char* requested_address,
67 const size_t noaccess_prefix) {
68 initialize(size+noaccess_prefix, alignment, large, requested_address,
69 noaccess_prefix, false);
70 }
71
72 ReservedSpace::ReservedSpace(size_t size, size_t alignment,
73 bool large,
74 bool executable) {
75 initialize(size, alignment, large, NULL, 0, executable);
76 }
77
78 // Helper method.
79 static bool failed_to_reserve_as_requested(char* base, char* requested_address,
80 const size_t size, bool special)
81 {
82 if (base == requested_address || requested_address == NULL)
83 return false; // did not fail
84
85 if (base != NULL) {
86 // Different reserve address may be acceptable in other cases
87 // but for compressed oops heap should be at requested address.
88 assert(UseCompressedOops, "currently requested address used only for compressed oops");
89 if (PrintCompressedOopsMode) {
90 tty->cr();
91 tty->print_cr("Reserved memory not at requested address: " PTR_FORMAT " vs " PTR_FORMAT, base, requested_address);
92 }
93 // OS ignored requested address. Try different address.
94 if (special) {
95 if (!os::release_memory_special(base, size)) {
96 fatal("os::release_memory_special failed");
97 }
98 } else {
99 if (!os::release_memory(base, size)) {
100 fatal("os::release_memory failed");
101 }
102 }
103 }
104 return true;
105 }
106
107 void ReservedSpace::initialize(size_t size, size_t alignment, bool large,
108 char* requested_address,
109 const size_t noaccess_prefix,
110 bool executable) {
111 const size_t granularity = os::vm_allocation_granularity();
112 assert((size & (granularity - 1)) == 0,
113 "size not aligned to os::vm_allocation_granularity()");
114 assert((alignment & (granularity - 1)) == 0,
115 "alignment not aligned to os::vm_allocation_granularity()");
116 assert(alignment == 0 || is_power_of_2((intptr_t)alignment),
117 "not a power of 2");
118
119 alignment = MAX2(alignment, (size_t)os::vm_page_size());
120
121 // Assert that if noaccess_prefix is used, it is the same as alignment.
122 assert(noaccess_prefix == 0 ||
123 noaccess_prefix == alignment, "noaccess prefix wrong");
124
125 _base = NULL;
126 _size = 0;
127 _special = false;
128 _executable = executable;
129 _alignment = 0;
130 _noaccess_prefix = 0;
131 if (size == 0) {
132 return;
133 }
134
135 // If OS doesn't support demand paging for large page memory, we need
136 // to use reserve_memory_special() to reserve and pin the entire region.
137 bool special = large && !os::can_commit_large_page_memory();
138 char* base = NULL;
139
140 if (requested_address != 0) {
141 requested_address -= noaccess_prefix; // adjust requested address
142 assert(requested_address != NULL, "huge noaccess prefix?");
143 }
144
145 if (special) {
146
147 base = os::reserve_memory_special(size, alignment, requested_address, executable);
148
149 if (base != NULL) {
150 if (failed_to_reserve_as_requested(base, requested_address, size, true)) {
151 // OS ignored requested address. Try different address.
152 return;
153 }
154 // Check alignment constraints.
155 assert((uintptr_t) base % alignment == 0,
156 err_msg("Large pages returned a non-aligned address, base: "
157 PTR_FORMAT " alignment: " PTR_FORMAT,
158 base, (void*)(uintptr_t)alignment));
159 _special = true;
160 } else {
161 // failed; try to reserve regular memory below
162 if (UseLargePages && (!FLAG_IS_DEFAULT(UseLargePages) ||
163 !FLAG_IS_DEFAULT(LargePageSizeInBytes))) {
164 if (PrintCompressedOopsMode) {
165 tty->cr();
166 tty->print_cr("Reserve regular memory without large pages.");
167 }
168 }
169 }
170 }
171
172 if (base == NULL) {
173 // Optimistically assume that the OSes returns an aligned base pointer.
174 // When reserving a large address range, most OSes seem to align to at
175 // least 64K.
176
177 // If the memory was requested at a particular address, use
178 // os::attempt_reserve_memory_at() to avoid over mapping something
179 // important. If available space is not detected, return NULL.
180
181 if (requested_address != 0) {
182 base = os::attempt_reserve_memory_at(size, requested_address);
183 if (failed_to_reserve_as_requested(base, requested_address, size, false)) {
184 // OS ignored requested address. Try different address.
185 base = NULL;
186 }
187 } else {
188 base = os::reserve_memory(size, NULL, alignment);
189 }
190
191 if (base == NULL) return;
192
193 // Check alignment constraints
194 if ((((size_t)base + noaccess_prefix) & (alignment - 1)) != 0) {
195 // Base not aligned, retry
196 if (!os::release_memory(base, size)) fatal("os::release_memory failed");
197 // Make sure that size is aligned
198 size = align_size_up(size, alignment);
199 base = os::reserve_memory_aligned(size, alignment);
200
201 if (requested_address != 0 &&
202 failed_to_reserve_as_requested(base, requested_address, size, false)) {
203 // As a result of the alignment constraints, the allocated base differs
204 // from the requested address. Return back to the caller who can
205 // take remedial action (like try again without a requested address).
206 assert(_base == NULL, "should be");
207 return;
208 }
209 }
210 }
211 // Done
212 _base = base;
213 _size = size;
214 _alignment = alignment;
215 _noaccess_prefix = noaccess_prefix;
216
217 // Assert that if noaccess_prefix is used, it is the same as alignment.
218 assert(noaccess_prefix == 0 ||
219 noaccess_prefix == _alignment, "noaccess prefix wrong");
220
221 assert(markOopDesc::encode_pointer_as_mark(_base)->decode_pointer() == _base,
222 "area must be distinguisable from marks for mark-sweep");
223 assert(markOopDesc::encode_pointer_as_mark(&_base[size])->decode_pointer() == &_base[size],
224 "area must be distinguisable from marks for mark-sweep");
225 }
226
227
228 ReservedSpace::ReservedSpace(char* base, size_t size, size_t alignment,
229 bool special, bool executable) {
230 assert((size % os::vm_allocation_granularity()) == 0,
231 "size not allocation aligned");
232 _base = base;
233 _size = size;
234 _alignment = alignment;
235 _noaccess_prefix = 0;
236 _special = special;
237 _executable = executable;
238 }
239
240
241 ReservedSpace ReservedSpace::first_part(size_t partition_size, size_t alignment,
242 bool split, bool realloc) {
243 assert(partition_size <= size(), "partition failed");
244 if (split) {
245 os::split_reserved_memory(base(), size(), partition_size, realloc);
246 }
247 ReservedSpace result(base(), partition_size, alignment, special(),
248 executable());
249 return result;
250 }
251
252
253 ReservedSpace
254 ReservedSpace::last_part(size_t partition_size, size_t alignment) {
255 assert(partition_size <= size(), "partition failed");
256 ReservedSpace result(base() + partition_size, size() - partition_size,
257 alignment, special(), executable());
258 return result;
259 }
260
261
262 size_t ReservedSpace::page_align_size_up(size_t size) {
263 return align_size_up(size, os::vm_page_size());
264 }
265
266
267 size_t ReservedSpace::page_align_size_down(size_t size) {
268 return align_size_down(size, os::vm_page_size());
269 }
270
271
272 size_t ReservedSpace::allocation_align_size_up(size_t size) {
273 return align_size_up(size, os::vm_allocation_granularity());
274 }
275
276
277 size_t ReservedSpace::allocation_align_size_down(size_t size) {
278 return align_size_down(size, os::vm_allocation_granularity());
279 }
280
281
282 void ReservedSpace::release() {
283 if (is_reserved()) {
284 char *real_base = _base - _noaccess_prefix;
285 const size_t real_size = _size + _noaccess_prefix;
286 if (special()) {
287 os::release_memory_special(real_base, real_size);
288 } else{
289 os::release_memory(real_base, real_size);
290 }
291 _base = NULL;
292 _size = 0;
293 _noaccess_prefix = 0;
294 _special = false;
295 _executable = false;
296 }
297 }
298
299 void ReservedSpace::protect_noaccess_prefix(const size_t size) {
300 assert( (_noaccess_prefix != 0) == (UseCompressedOops && _base != NULL &&
301 (Universe::narrow_oop_base() != NULL) &&
302 Universe::narrow_oop_use_implicit_null_checks()),
303 "noaccess_prefix should be used only with non zero based compressed oops");
304
305 // If there is no noaccess prefix, return.
306 if (_noaccess_prefix == 0) return;
307
308 assert(_noaccess_prefix >= (size_t)os::vm_page_size(),
309 "must be at least page size big");
310
311 // Protect memory at the base of the allocated region.
312 // If special, the page was committed (only matters on windows)
313 if (!os::protect_memory(_base, _noaccess_prefix, os::MEM_PROT_NONE,
314 _special)) {
315 fatal("cannot protect protection page");
316 }
317 if (PrintCompressedOopsMode) {
318 tty->cr();
319 tty->print_cr("Protected page at the reserved heap base: " PTR_FORMAT " / " INTX_FORMAT " bytes", _base, _noaccess_prefix);
320 }
321
322 _base += _noaccess_prefix;
323 _size -= _noaccess_prefix;
324 assert((size == _size) && ((uintptr_t)_base % _alignment == 0),
325 "must be exactly of required size and alignment");
326 }
327
328 ReservedHeapSpace::ReservedHeapSpace(size_t size, size_t alignment,
329 bool large, char* requested_address) :
330 ReservedSpace(size, alignment, large,
331 requested_address,
332 (UseCompressedOops && (Universe::narrow_oop_base() != NULL) &&
333 Universe::narrow_oop_use_implicit_null_checks()) ?
334 lcm(os::vm_page_size(), alignment) : 0) {
335 if (base() > 0) {
336 MemTracker::record_virtual_memory_type((address)base(), mtJavaHeap);
337 }
338
339 // Only reserved space for the java heap should have a noaccess_prefix
340 // if using compressed oops.
341 protect_noaccess_prefix(size);
342 }
343
344 // Reserve space for code segment. Same as Java heap only we mark this as
345 // executable.
346 ReservedCodeSpace::ReservedCodeSpace(size_t r_size,
347 size_t rs_align,
348 bool large) :
349 ReservedSpace(r_size, rs_align, large, /*executable*/ true) {
350 MemTracker::record_virtual_memory_type((address)base(), mtCode);
351 }
352
353 // VirtualSpace
354
355 VirtualSpace::VirtualSpace() {
356 _low_boundary = NULL;
357 _high_boundary = NULL;
358 _low = NULL;
359 _high = NULL;
360 _lower_high = NULL;
361 _middle_high = NULL;
362 _upper_high = NULL;
363 _lower_high_boundary = NULL;
364 _middle_high_boundary = NULL;
365 _upper_high_boundary = NULL;
366 _lower_alignment = 0;
367 _middle_alignment = 0;
368 _upper_alignment = 0;
369 _special = false;
370 _executable = false;
371 }
372
373
374 bool VirtualSpace::initialize(ReservedSpace rs, size_t committed_size) {
375 const size_t max_commit_granularity = os::page_size_for_region(rs.size(), 1);
376 return initialize_with_granularity(rs, committed_size, max_commit_granularity);
377 }
378
379 bool VirtualSpace::initialize_with_granularity(ReservedSpace rs, size_t committed_size, size_t max_commit_granularity) {
380 if(!rs.is_reserved()) return false; // allocation failed.
381 assert(_low_boundary == NULL, "VirtualSpace already initialized");
382 assert(max_commit_granularity > 0, "Granularity must be non-zero.");
383
384 _low_boundary = rs.base();
385 _high_boundary = low_boundary() + rs.size();
386
387 _low = low_boundary();
388 _high = low();
389
390 _special = rs.special();
391 _executable = rs.executable();
392
393 // When a VirtualSpace begins life at a large size, make all future expansion
394 // and shrinking occur aligned to a granularity of large pages. This avoids
395 // fragmentation of physical addresses that inhibits the use of large pages
396 // by the OS virtual memory system. Empirically, we see that with a 4MB
397 // page size, the only spaces that get handled this way are codecache and
398 // the heap itself, both of which provide a substantial performance
399 // boost in many benchmarks when covered by large pages.
400 //
401 // No attempt is made to force large page alignment at the very top and
402 // bottom of the space if they are not aligned so already.
403 _lower_alignment = os::vm_page_size();
404 _middle_alignment = max_commit_granularity;
405 _upper_alignment = os::vm_page_size();
406
407 // End of each region
408 _lower_high_boundary = (char*) round_to((intptr_t) low_boundary(), middle_alignment());
409 _middle_high_boundary = (char*) round_down((intptr_t) high_boundary(), middle_alignment());
410 _upper_high_boundary = high_boundary();
411
412 // High address of each region
413 _lower_high = low_boundary();
414 _middle_high = lower_high_boundary();
415 _upper_high = middle_high_boundary();
416
417 // commit to initial size
418 if (committed_size > 0) {
419 if (!expand_by(committed_size)) {
420 return false;
421 }
422 }
423 return true;
424 }
425
426
427 VirtualSpace::~VirtualSpace() {
428 release();
429 }
430
431
432 void VirtualSpace::release() {
433 // This does not release memory it never reserved.
434 // Caller must release via rs.release();
435 _low_boundary = NULL;
436 _high_boundary = NULL;
437 _low = NULL;
438 _high = NULL;
439 _lower_high = NULL;
440 _middle_high = NULL;
441 _upper_high = NULL;
442 _lower_high_boundary = NULL;
443 _middle_high_boundary = NULL;
444 _upper_high_boundary = NULL;
445 _lower_alignment = 0;
446 _middle_alignment = 0;
447 _upper_alignment = 0;
448 _special = false;
449 _executable = false;
450 }
451
452
453 size_t VirtualSpace::committed_size() const {
454 return pointer_delta(high(), low(), sizeof(char));
455 }
456
457
458 size_t VirtualSpace::reserved_size() const {
459 return pointer_delta(high_boundary(), low_boundary(), sizeof(char));
460 }
461
462
463 size_t VirtualSpace::uncommitted_size() const {
464 return reserved_size() - committed_size();
465 }
466
467 size_t VirtualSpace::actual_committed_size() const {
468 // Special VirtualSpaces commit all reserved space up front.
469 if (special()) {
470 return reserved_size();
471 }
472
473 size_t committed_low = pointer_delta(_lower_high, _low_boundary, sizeof(char));
474 size_t committed_middle = pointer_delta(_middle_high, _lower_high_boundary, sizeof(char));
475 size_t committed_high = pointer_delta(_upper_high, _middle_high_boundary, sizeof(char));
476
477 #ifdef ASSERT
478 size_t lower = pointer_delta(_lower_high_boundary, _low_boundary, sizeof(char));
479 size_t middle = pointer_delta(_middle_high_boundary, _lower_high_boundary, sizeof(char));
480 size_t upper = pointer_delta(_upper_high_boundary, _middle_high_boundary, sizeof(char));
481
482 if (committed_high > 0) {
483 assert(committed_low == lower, "Must be");
484 assert(committed_middle == middle, "Must be");
485 }
486
487 if (committed_middle > 0) {
488 assert(committed_low == lower, "Must be");
489 }
490 if (committed_middle < middle) {
491 assert(committed_high == 0, "Must be");
492 }
493
494 if (committed_low < lower) {
495 assert(committed_high == 0, "Must be");
496 assert(committed_middle == 0, "Must be");
497 }
498 #endif
499
500 return committed_low + committed_middle + committed_high;
501 }
502
503
504 bool VirtualSpace::contains(const void* p) const {
505 return low() <= (const char*) p && (const char*) p < high();
506 }
507
508 /*
509 First we need to determine if a particular virtual space is using large
510 pages. This is done at the initialize function and only virtual spaces
511 that are larger than LargePageSizeInBytes use large pages. Once we
512 have determined this, all expand_by and shrink_by calls must grow and
513 shrink by large page size chunks. If a particular request
514 is within the current large page, the call to commit and uncommit memory
515 can be ignored. In the case that the low and high boundaries of this
516 space is not large page aligned, the pages leading to the first large
517 page address and the pages after the last large page address must be
518 allocated with default pages.
519 */
520 bool VirtualSpace::expand_by(size_t bytes, bool pre_touch) {
521 if (uncommitted_size() < bytes) return false;
522
523 if (special()) {
524 // don't commit memory if the entire space is pinned in memory
525 _high += bytes;
526 return true;
527 }
528
529 char* previous_high = high();
530 char* unaligned_new_high = high() + bytes;
531 assert(unaligned_new_high <= high_boundary(),
532 "cannot expand by more than upper boundary");
533
534 // Calculate where the new high for each of the regions should be. If
535 // the low_boundary() and high_boundary() are LargePageSizeInBytes aligned
536 // then the unaligned lower and upper new highs would be the
537 // lower_high() and upper_high() respectively.
538 char* unaligned_lower_new_high =
539 MIN2(unaligned_new_high, lower_high_boundary());
540 char* unaligned_middle_new_high =
541 MIN2(unaligned_new_high, middle_high_boundary());
542 char* unaligned_upper_new_high =
543 MIN2(unaligned_new_high, upper_high_boundary());
544
545 // Align the new highs based on the regions alignment. lower and upper
546 // alignment will always be default page size. middle alignment will be
547 // LargePageSizeInBytes if the actual size of the virtual space is in
548 // fact larger than LargePageSizeInBytes.
549 char* aligned_lower_new_high =
550 (char*) round_to((intptr_t) unaligned_lower_new_high, lower_alignment());
551 char* aligned_middle_new_high =
552 (char*) round_to((intptr_t) unaligned_middle_new_high, middle_alignment());
553 char* aligned_upper_new_high =
554 (char*) round_to((intptr_t) unaligned_upper_new_high, upper_alignment());
555
556 // Determine which regions need to grow in this expand_by call.
557 // If you are growing in the lower region, high() must be in that
558 // region so calcuate the size based on high(). For the middle and
559 // upper regions, determine the starting point of growth based on the
560 // location of high(). By getting the MAX of the region's low address
561 // (or the prevoius region's high address) and high(), we can tell if it
562 // is an intra or inter region growth.
563 size_t lower_needs = 0;
564 if (aligned_lower_new_high > lower_high()) {
565 lower_needs =
566 pointer_delta(aligned_lower_new_high, lower_high(), sizeof(char));
567 }
568 size_t middle_needs = 0;
569 if (aligned_middle_new_high > middle_high()) {
570 middle_needs =
571 pointer_delta(aligned_middle_new_high, middle_high(), sizeof(char));
572 }
573 size_t upper_needs = 0;
574 if (aligned_upper_new_high > upper_high()) {
575 upper_needs =
576 pointer_delta(aligned_upper_new_high, upper_high(), sizeof(char));
577 }
578
579 // Check contiguity.
580 assert(low_boundary() <= lower_high() &&
581 lower_high() <= lower_high_boundary(),
582 "high address must be contained within the region");
583 assert(lower_high_boundary() <= middle_high() &&
584 middle_high() <= middle_high_boundary(),
585 "high address must be contained within the region");
586 assert(middle_high_boundary() <= upper_high() &&
587 upper_high() <= upper_high_boundary(),
588 "high address must be contained within the region");
589
590 // Commit regions
591 if (lower_needs > 0) {
592 assert(low_boundary() <= lower_high() &&
593 lower_high() + lower_needs <= lower_high_boundary(),
594 "must not expand beyond region");
595 if (!os::commit_memory(lower_high(), lower_needs, _executable)) {
596 debug_only(warning("INFO: os::commit_memory(" PTR_FORMAT
597 ", lower_needs=" SIZE_FORMAT ", %d) failed",
598 lower_high(), lower_needs, _executable);)
599 return false;
600 } else {
601 _lower_high += lower_needs;
602 }
603 }
604 if (middle_needs > 0) {
605 assert(lower_high_boundary() <= middle_high() &&
606 middle_high() + middle_needs <= middle_high_boundary(),
607 "must not expand beyond region");
608 if (!os::commit_memory(middle_high(), middle_needs, middle_alignment(),
609 _executable)) {
610 debug_only(warning("INFO: os::commit_memory(" PTR_FORMAT
611 ", middle_needs=" SIZE_FORMAT ", " SIZE_FORMAT
612 ", %d) failed", middle_high(), middle_needs,
613 middle_alignment(), _executable);)
614 return false;
615 }
616 _middle_high += middle_needs;
617 }
618 if (upper_needs > 0) {
619 assert(middle_high_boundary() <= upper_high() &&
620 upper_high() + upper_needs <= upper_high_boundary(),
621 "must not expand beyond region");
622 if (!os::commit_memory(upper_high(), upper_needs, _executable)) {
623 debug_only(warning("INFO: os::commit_memory(" PTR_FORMAT
624 ", upper_needs=" SIZE_FORMAT ", %d) failed",
625 upper_high(), upper_needs, _executable);)
626 return false;
627 } else {
628 _upper_high += upper_needs;
629 }
630 }
631
632 if (pre_touch || AlwaysPreTouch) {
633 os::pretouch_memory(previous_high, unaligned_new_high);
634 }
635
636 _high += bytes;
637 return true;
638 }
639
640 // A page is uncommitted if the contents of the entire page is deemed unusable.
641 // Continue to decrement the high() pointer until it reaches a page boundary
642 // in which case that particular page can now be uncommitted.
643 void VirtualSpace::shrink_by(size_t size) {
644 if (committed_size() < size)
645 fatal("Cannot shrink virtual space to negative size");
646
647 if (special()) {
648 // don't uncommit if the entire space is pinned in memory
649 _high -= size;
650 return;
651 }
652
653 char* unaligned_new_high = high() - size;
654 assert(unaligned_new_high >= low_boundary(), "cannot shrink past lower boundary");
655
656 // Calculate new unaligned address
657 char* unaligned_upper_new_high =
658 MAX2(unaligned_new_high, middle_high_boundary());
659 char* unaligned_middle_new_high =
660 MAX2(unaligned_new_high, lower_high_boundary());
661 char* unaligned_lower_new_high =
662 MAX2(unaligned_new_high, low_boundary());
663
664 // Align address to region's alignment
665 char* aligned_upper_new_high =
666 (char*) round_to((intptr_t) unaligned_upper_new_high, upper_alignment());
667 char* aligned_middle_new_high =
668 (char*) round_to((intptr_t) unaligned_middle_new_high, middle_alignment());
669 char* aligned_lower_new_high =
670 (char*) round_to((intptr_t) unaligned_lower_new_high, lower_alignment());
671
672 // Determine which regions need to shrink
673 size_t upper_needs = 0;
674 if (aligned_upper_new_high < upper_high()) {
675 upper_needs =
676 pointer_delta(upper_high(), aligned_upper_new_high, sizeof(char));
677 }
678 size_t middle_needs = 0;
679 if (aligned_middle_new_high < middle_high()) {
680 middle_needs =
681 pointer_delta(middle_high(), aligned_middle_new_high, sizeof(char));
682 }
683 size_t lower_needs = 0;
684 if (aligned_lower_new_high < lower_high()) {
685 lower_needs =
686 pointer_delta(lower_high(), aligned_lower_new_high, sizeof(char));
687 }
688
689 // Check contiguity.
690 assert(middle_high_boundary() <= upper_high() &&
691 upper_high() <= upper_high_boundary(),
692 "high address must be contained within the region");
693 assert(lower_high_boundary() <= middle_high() &&
694 middle_high() <= middle_high_boundary(),
695 "high address must be contained within the region");
696 assert(low_boundary() <= lower_high() &&
697 lower_high() <= lower_high_boundary(),
698 "high address must be contained within the region");
699
700 // Uncommit
701 if (upper_needs > 0) {
702 assert(middle_high_boundary() <= aligned_upper_new_high &&
703 aligned_upper_new_high + upper_needs <= upper_high_boundary(),
704 "must not shrink beyond region");
705 if (!os::uncommit_memory(aligned_upper_new_high, upper_needs)) {
706 debug_only(warning("os::uncommit_memory failed"));
707 return;
708 } else {
709 _upper_high -= upper_needs;
710 }
711 }
712 if (middle_needs > 0) {
713 assert(lower_high_boundary() <= aligned_middle_new_high &&
714 aligned_middle_new_high + middle_needs <= middle_high_boundary(),
715 "must not shrink beyond region");
716 if (!os::uncommit_memory(aligned_middle_new_high, middle_needs)) {
717 debug_only(warning("os::uncommit_memory failed"));
718 return;
719 } else {
720 _middle_high -= middle_needs;
721 }
722 }
723 if (lower_needs > 0) {
724 assert(low_boundary() <= aligned_lower_new_high &&
725 aligned_lower_new_high + lower_needs <= lower_high_boundary(),
726 "must not shrink beyond region");
727 if (!os::uncommit_memory(aligned_lower_new_high, lower_needs)) {
728 debug_only(warning("os::uncommit_memory failed"));
729 return;
730 } else {
731 _lower_high -= lower_needs;
732 }
733 }
734
735 _high -= size;
736 }
737
738 #ifndef PRODUCT
739 void VirtualSpace::check_for_contiguity() {
740 // Check contiguity.
741 assert(low_boundary() <= lower_high() &&
742 lower_high() <= lower_high_boundary(),
743 "high address must be contained within the region");
744 assert(lower_high_boundary() <= middle_high() &&
745 middle_high() <= middle_high_boundary(),
746 "high address must be contained within the region");
747 assert(middle_high_boundary() <= upper_high() &&
748 upper_high() <= upper_high_boundary(),
749 "high address must be contained within the region");
750 assert(low() >= low_boundary(), "low");
751 assert(low_boundary() <= lower_high_boundary(), "lower high boundary");
752 assert(upper_high_boundary() <= high_boundary(), "upper high boundary");
753 assert(high() <= upper_high(), "upper high");
754 }
755
756 void VirtualSpace::print_on(outputStream* out) {
757 out->print ("Virtual space:");
758 if (special()) out->print(" (pinned in memory)");
759 out->cr();
760 out->print_cr(" - committed: " SIZE_FORMAT, committed_size());
761 out->print_cr(" - reserved: " SIZE_FORMAT, reserved_size());
762 out->print_cr(" - [low, high]: [" INTPTR_FORMAT ", " INTPTR_FORMAT "]", low(), high());
763 out->print_cr(" - [low_b, high_b]: [" INTPTR_FORMAT ", " INTPTR_FORMAT "]", low_boundary(), high_boundary());
764 }
765
766 void VirtualSpace::print() {
767 print_on(tty);
768 }
769
770 /////////////// Unit tests ///////////////
771
772 #ifndef PRODUCT
773
774 #define test_log(...) \
775 do {\
776 if (VerboseInternalVMTests) { \
777 tty->print_cr(__VA_ARGS__); \
778 tty->flush(); \
779 }\
780 } while (false)
781
782 class TestReservedSpace : AllStatic {
783 public:
784 static void small_page_write(void* addr, size_t size) {
785 size_t page_size = os::vm_page_size();
786
787 char* end = (char*)addr + size;
788 for (char* p = (char*)addr; p < end; p += page_size) {
789 *p = 1;
790 }
791 }
792
793 static void release_memory_for_test(ReservedSpace rs) {
794 if (rs.special()) {
795 guarantee(os::release_memory_special(rs.base(), rs.size()), "Shouldn't fail");
796 } else {
797 guarantee(os::release_memory(rs.base(), rs.size()), "Shouldn't fail");
798 }
799 }
800
801 static void test_reserved_space1(size_t size, size_t alignment) {
802 test_log("test_reserved_space1(%p)", (void*) (uintptr_t) size);
803
804 assert(is_size_aligned(size, alignment), "Incorrect input parameters");
805
806 ReservedSpace rs(size, // size
807 alignment, // alignment
808 UseLargePages, // large
809 NULL, // requested_address
810 0); // noacces_prefix
811
812 test_log(" rs.special() == %d", rs.special());
813
814 assert(rs.base() != NULL, "Must be");
815 assert(rs.size() == size, "Must be");
816
817 assert(is_ptr_aligned(rs.base(), alignment), "aligned sizes should always give aligned addresses");
818 assert(is_size_aligned(rs.size(), alignment), "aligned sizes should always give aligned addresses");
819
820 if (rs.special()) {
821 small_page_write(rs.base(), size);
822 }
823
824 release_memory_for_test(rs);
825 }
826
827 static void test_reserved_space2(size_t size) {
828 test_log("test_reserved_space2(%p)", (void*)(uintptr_t)size);
829
830 assert(is_size_aligned(size, os::vm_allocation_granularity()), "Must be at least AG aligned");
831
832 ReservedSpace rs(size);
833
834 test_log(" rs.special() == %d", rs.special());
835
836 assert(rs.base() != NULL, "Must be");
837 assert(rs.size() == size, "Must be");
838
839 if (rs.special()) {
840 small_page_write(rs.base(), size);
841 }
842
843 release_memory_for_test(rs);
844 }
845
846 static void test_reserved_space3(size_t size, size_t alignment, bool maybe_large) {
847 test_log("test_reserved_space3(%p, %p, %d)",
848 (void*)(uintptr_t)size, (void*)(uintptr_t)alignment, maybe_large);
849
850 assert(is_size_aligned(size, os::vm_allocation_granularity()), "Must be at least AG aligned");
851 assert(is_size_aligned(size, alignment), "Must be at least aligned against alignment");
852
853 bool large = maybe_large && UseLargePages && size >= os::large_page_size();
854
855 ReservedSpace rs(size, alignment, large, false);
856
857 test_log(" rs.special() == %d", rs.special());
858
859 assert(rs.base() != NULL, "Must be");
860 assert(rs.size() == size, "Must be");
861
862 if (rs.special()) {
863 small_page_write(rs.base(), size);
864 }
865
866 release_memory_for_test(rs);
867 }
868
869
870 static void test_reserved_space1() {
871 size_t size = 2 * 1024 * 1024;
872 size_t ag = os::vm_allocation_granularity();
873
874 test_reserved_space1(size, ag);
875 test_reserved_space1(size * 2, ag);
876 test_reserved_space1(size * 10, ag);
877 }
878
879 static void test_reserved_space2() {
880 size_t size = 2 * 1024 * 1024;
881 size_t ag = os::vm_allocation_granularity();
882
883 test_reserved_space2(size * 1);
884 test_reserved_space2(size * 2);
885 test_reserved_space2(size * 10);
886 test_reserved_space2(ag);
887 test_reserved_space2(size - ag);
888 test_reserved_space2(size);
889 test_reserved_space2(size + ag);
890 test_reserved_space2(size * 2);
891 test_reserved_space2(size * 2 - ag);
892 test_reserved_space2(size * 2 + ag);
893 test_reserved_space2(size * 3);
894 test_reserved_space2(size * 3 - ag);
895 test_reserved_space2(size * 3 + ag);
896 test_reserved_space2(size * 10);
897 test_reserved_space2(size * 10 + size / 2);
898 }
899
900 static void test_reserved_space3() {
901 size_t ag = os::vm_allocation_granularity();
902
903 test_reserved_space3(ag, ag , false);
904 test_reserved_space3(ag * 2, ag , false);
905 test_reserved_space3(ag * 3, ag , false);
906 test_reserved_space3(ag * 2, ag * 2, false);
907 test_reserved_space3(ag * 4, ag * 2, false);
908 test_reserved_space3(ag * 8, ag * 2, false);
909 test_reserved_space3(ag * 4, ag * 4, false);
910 test_reserved_space3(ag * 8, ag * 4, false);
911 test_reserved_space3(ag * 16, ag * 4, false);
912
913 if (UseLargePages) {
914 size_t lp = os::large_page_size();
915
916 // Without large pages
917 test_reserved_space3(lp, ag * 4, false);
918 test_reserved_space3(lp * 2, ag * 4, false);
919 test_reserved_space3(lp * 4, ag * 4, false);
920 test_reserved_space3(lp, lp , false);
921 test_reserved_space3(lp * 2, lp , false);
922 test_reserved_space3(lp * 3, lp , false);
923 test_reserved_space3(lp * 2, lp * 2, false);
924 test_reserved_space3(lp * 4, lp * 2, false);
925 test_reserved_space3(lp * 8, lp * 2, false);
926
927 // With large pages
928 test_reserved_space3(lp, ag * 4 , true);
929 test_reserved_space3(lp * 2, ag * 4, true);
930 test_reserved_space3(lp * 4, ag * 4, true);
931 test_reserved_space3(lp, lp , true);
932 test_reserved_space3(lp * 2, lp , true);
933 test_reserved_space3(lp * 3, lp , true);
934 test_reserved_space3(lp * 2, lp * 2, true);
935 test_reserved_space3(lp * 4, lp * 2, true);
936 test_reserved_space3(lp * 8, lp * 2, true);
937 }
938 }
939
940 static void test_reserved_space() {
941 test_reserved_space1();
942 test_reserved_space2();
943 test_reserved_space3();
944 }
945 };
946
947 void TestReservedSpace_test() {
948 TestReservedSpace::test_reserved_space();
949 }
950
951 #define assert_equals(actual, expected) \
952 assert(actual == expected, \
953 err_msg("Got " SIZE_FORMAT " expected " \
954 SIZE_FORMAT, actual, expected));
955
956 #define assert_ge(value1, value2) \
957 assert(value1 >= value2, \
958 err_msg("'" #value1 "': " SIZE_FORMAT " '" \
959 #value2 "': " SIZE_FORMAT, value1, value2));
960
961 #define assert_lt(value1, value2) \
962 assert(value1 < value2, \
963 err_msg("'" #value1 "': " SIZE_FORMAT " '" \
964 #value2 "': " SIZE_FORMAT, value1, value2));
965
966
967 class TestVirtualSpace : AllStatic {
968 enum TestLargePages {
969 Default,
970 Disable,
971 Reserve,
972 Commit
973 };
974
975 static ReservedSpace reserve_memory(size_t reserve_size_aligned, TestLargePages mode) {
976 switch(mode) {
977 default:
978 case Default:
979 case Reserve:
980 return ReservedSpace(reserve_size_aligned);
981 case Disable:
982 case Commit:
983 return ReservedSpace(reserve_size_aligned,
984 os::vm_allocation_granularity(),
985 /* large */ false, /* exec */ false);
986 }
987 }
988
989 static bool initialize_virtual_space(VirtualSpace& vs, ReservedSpace rs, TestLargePages mode) {
990 switch(mode) {
991 default:
992 case Default:
993 case Reserve:
994 return vs.initialize(rs, 0);
995 case Disable:
996 return vs.initialize_with_granularity(rs, 0, os::vm_page_size());
997 case Commit:
998 return vs.initialize_with_granularity(rs, 0, os::page_size_for_region(rs.size(), 1));
999 }
1000 }
1001
1002 public:
1003 static void test_virtual_space_actual_committed_space(size_t reserve_size, size_t commit_size,
1004 TestLargePages mode = Default) {
1005 size_t granularity = os::vm_allocation_granularity();
1006 size_t reserve_size_aligned = align_size_up(reserve_size, granularity);
1007
1008 ReservedSpace reserved = reserve_memory(reserve_size_aligned, mode);
1009
1010 assert(reserved.is_reserved(), "Must be");
1011
1012 VirtualSpace vs;
1013 bool initialized = initialize_virtual_space(vs, reserved, mode);
1014 assert(initialized, "Failed to initialize VirtualSpace");
1015
1016 vs.expand_by(commit_size, false);
1017
1018 if (vs.special()) {
1019 assert_equals(vs.actual_committed_size(), reserve_size_aligned);
1020 } else {
1021 assert_ge(vs.actual_committed_size(), commit_size);
1022 // Approximate the commit granularity.
1023 // Make sure that we don't commit using large pages
1024 // if large pages has been disabled for this VirtualSpace.
1025 size_t commit_granularity = (mode == Disable || !UseLargePages) ?
1026 os::vm_page_size() : os::large_page_size();
1027 assert_lt(vs.actual_committed_size(), commit_size + commit_granularity);
1028 }
1029
1030 reserved.release();
1031 }
1032
1033 static void test_virtual_space_actual_committed_space_one_large_page() {
1034 if (!UseLargePages) {
1035 return;
1036 }
1037
1038 size_t large_page_size = os::large_page_size();
1039
1040 ReservedSpace reserved(large_page_size, large_page_size, true, false);
1041
1042 assert(reserved.is_reserved(), "Must be");
1043
1044 VirtualSpace vs;
1045 bool initialized = vs.initialize(reserved, 0);
1046 assert(initialized, "Failed to initialize VirtualSpace");
1047
1048 vs.expand_by(large_page_size, false);
1049
1050 assert_equals(vs.actual_committed_size(), large_page_size);
1051
1052 reserved.release();
1053 }
1054
1055 static void test_virtual_space_actual_committed_space() {
1056 test_virtual_space_actual_committed_space(4 * K, 0);
1057 test_virtual_space_actual_committed_space(4 * K, 4 * K);
1058 test_virtual_space_actual_committed_space(8 * K, 0);
1059 test_virtual_space_actual_committed_space(8 * K, 4 * K);
1060 test_virtual_space_actual_committed_space(8 * K, 8 * K);
1061 test_virtual_space_actual_committed_space(12 * K, 0);
1062 test_virtual_space_actual_committed_space(12 * K, 4 * K);
1063 test_virtual_space_actual_committed_space(12 * K, 8 * K);
1064 test_virtual_space_actual_committed_space(12 * K, 12 * K);
1065 test_virtual_space_actual_committed_space(64 * K, 0);
1066 test_virtual_space_actual_committed_space(64 * K, 32 * K);
1067 test_virtual_space_actual_committed_space(64 * K, 64 * K);
1068 test_virtual_space_actual_committed_space(2 * M, 0);
1069 test_virtual_space_actual_committed_space(2 * M, 4 * K);
1070 test_virtual_space_actual_committed_space(2 * M, 64 * K);
1071 test_virtual_space_actual_committed_space(2 * M, 1 * M);
1072 test_virtual_space_actual_committed_space(2 * M, 2 * M);
1073 test_virtual_space_actual_committed_space(10 * M, 0);
1074 test_virtual_space_actual_committed_space(10 * M, 4 * K);
1075 test_virtual_space_actual_committed_space(10 * M, 8 * K);
1076 test_virtual_space_actual_committed_space(10 * M, 1 * M);
1077 test_virtual_space_actual_committed_space(10 * M, 2 * M);
1078 test_virtual_space_actual_committed_space(10 * M, 5 * M);
1079 test_virtual_space_actual_committed_space(10 * M, 10 * M);
1080 }
1081
1082 static void test_virtual_space_disable_large_pages() {
1083 if (!UseLargePages) {
1084 return;
1085 }
1086 // These test cases verify that if we force VirtualSpace to disable large pages
1087 test_virtual_space_actual_committed_space(10 * M, 0, Disable);
1088 test_virtual_space_actual_committed_space(10 * M, 4 * K, Disable);
1089 test_virtual_space_actual_committed_space(10 * M, 8 * K, Disable);
1090 test_virtual_space_actual_committed_space(10 * M, 1 * M, Disable);
1091 test_virtual_space_actual_committed_space(10 * M, 2 * M, Disable);
1092 test_virtual_space_actual_committed_space(10 * M, 5 * M, Disable);
1093 test_virtual_space_actual_committed_space(10 * M, 10 * M, Disable);
1094
1095 test_virtual_space_actual_committed_space(10 * M, 0, Reserve);
1096 test_virtual_space_actual_committed_space(10 * M, 4 * K, Reserve);
1097 test_virtual_space_actual_committed_space(10 * M, 8 * K, Reserve);
1098 test_virtual_space_actual_committed_space(10 * M, 1 * M, Reserve);
1099 test_virtual_space_actual_committed_space(10 * M, 2 * M, Reserve);
1100 test_virtual_space_actual_committed_space(10 * M, 5 * M, Reserve);
1101 test_virtual_space_actual_committed_space(10 * M, 10 * M, Reserve);
1102
1103 test_virtual_space_actual_committed_space(10 * M, 0, Commit);
1104 test_virtual_space_actual_committed_space(10 * M, 4 * K, Commit);
1105 test_virtual_space_actual_committed_space(10 * M, 8 * K, Commit);
1106 test_virtual_space_actual_committed_space(10 * M, 1 * M, Commit);
1107 test_virtual_space_actual_committed_space(10 * M, 2 * M, Commit);
1108 test_virtual_space_actual_committed_space(10 * M, 5 * M, Commit);
1109 test_virtual_space_actual_committed_space(10 * M, 10 * M, Commit);
1110 }
1111
1112 static void test_virtual_space() {
1113 test_virtual_space_actual_committed_space();
1114 test_virtual_space_actual_committed_space_one_large_page();
1115 test_virtual_space_disable_large_pages();
1116 }
1117 };
1118
1119 void TestVirtualSpace_test() {
1120 TestVirtualSpace::test_virtual_space();
1121 }
1122
1123 #endif // PRODUCT
1124
1125 #endif