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 "classfile/classLoader.hpp"
27 #include "classfile/javaClasses.hpp"
28 #include "classfile/systemDictionary.hpp"
29 #include "classfile/vmSymbols.hpp"
30 #include "code/codeCache.hpp"
31 #include "code/icBuffer.hpp"
32 #include "code/vtableStubs.hpp"
33 #include "gc/shared/vmGCOperations.hpp"
34 #include "interpreter/interpreter.hpp"
35 #include "logging/log.hpp"
36 #include "memory/allocation.inline.hpp"
37 #ifdef ASSERT
38 #include "memory/guardedMemory.hpp"
39 #endif
40 #include "oops/oop.inline.hpp"
41 #include "prims/jvm.h"
42 #include "prims/jvm_misc.hpp"
43 #include "prims/privilegedStack.hpp"
44 #include "runtime/arguments.hpp"
45 #include "runtime/atomic.inline.hpp"
46 #include "runtime/frame.inline.hpp"
47 #include "runtime/interfaceSupport.hpp"
48 #include "runtime/java.hpp"
49 #include "runtime/javaCalls.hpp"
50 #include "runtime/mutexLocker.hpp"
51 #include "runtime/os.inline.hpp"
52 #include "runtime/stubRoutines.hpp"
53 #include "runtime/thread.inline.hpp"
54 #include "runtime/vm_version.hpp"
55 #include "services/attachListener.hpp"
56 #include "services/mallocTracker.hpp"
57 #include "services/memTracker.hpp"
58 #include "services/nmtCommon.hpp"
59 #include "services/threadService.hpp"
60 #include "utilities/defaultStream.hpp"
61 #include "utilities/events.hpp"
62
63 # include <signal.h>
64 # include <errno.h>
65
66 OSThread* os::_starting_thread = NULL;
67 address os::_polling_page = NULL;
68 volatile int32_t* os::_mem_serialize_page = NULL;
69 uintptr_t os::_serialize_page_mask = 0;
70 long os::_rand_seed = 1;
71 int os::_processor_count = 0;
72 size_t os::_page_sizes[os::page_sizes_max];
73
74 #ifndef PRODUCT
75 julong os::num_mallocs = 0; // # of calls to malloc/realloc
76 julong os::alloc_bytes = 0; // # of bytes allocated
77 julong os::num_frees = 0; // # of calls to free
78 julong os::free_bytes = 0; // # of bytes freed
79 #endif
80
81 static juint cur_malloc_words = 0; // current size for MallocMaxTestWords
82
83 void os_init_globals() {
84 // Called from init_globals().
85 // See Threads::create_vm() in thread.cpp, and init.cpp.
86 os::init_globals();
87 }
88
89 // Fill in buffer with current local time as an ISO-8601 string.
90 // E.g., yyyy-mm-ddThh:mm:ss-zzzz.
91 // Returns buffer, or NULL if it failed.
92 // This would mostly be a call to
93 // strftime(...., "%Y-%m-%d" "T" "%H:%M:%S" "%z", ....)
94 // except that on Windows the %z behaves badly, so we do it ourselves.
95 // Also, people wanted milliseconds on there,
96 // and strftime doesn't do milliseconds.
97 char* os::iso8601_time(char* buffer, size_t buffer_length) {
98 // Output will be of the form "YYYY-MM-DDThh:mm:ss.mmm+zzzz\0"
99 // 1 2
100 // 12345678901234567890123456789
101 // format string: "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d"
102 static const size_t needed_buffer = 29;
103
104 // Sanity check the arguments
105 if (buffer == NULL) {
106 assert(false, "NULL buffer");
107 return NULL;
108 }
109 if (buffer_length < needed_buffer) {
110 assert(false, "buffer_length too small");
111 return NULL;
112 }
113 // Get the current time
114 jlong milliseconds_since_19700101 = javaTimeMillis();
115 const int milliseconds_per_microsecond = 1000;
116 const time_t seconds_since_19700101 =
117 milliseconds_since_19700101 / milliseconds_per_microsecond;
118 const int milliseconds_after_second =
119 milliseconds_since_19700101 % milliseconds_per_microsecond;
120 // Convert the time value to a tm and timezone variable
121 struct tm time_struct;
122 if (localtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
123 assert(false, "Failed localtime_pd");
124 return NULL;
125 }
126 #if defined(_ALLBSD_SOURCE)
127 const time_t zone = (time_t) time_struct.tm_gmtoff;
128 #else
129 const time_t zone = timezone;
130 #endif
131
132 // If daylight savings time is in effect,
133 // we are 1 hour East of our time zone
134 const time_t seconds_per_minute = 60;
135 const time_t minutes_per_hour = 60;
136 const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour;
137 time_t UTC_to_local = zone;
138 if (time_struct.tm_isdst > 0) {
139 UTC_to_local = UTC_to_local - seconds_per_hour;
140 }
141 // Compute the time zone offset.
142 // localtime_pd() sets timezone to the difference (in seconds)
143 // between UTC and and local time.
144 // ISO 8601 says we need the difference between local time and UTC,
145 // we change the sign of the localtime_pd() result.
146 const time_t local_to_UTC = -(UTC_to_local);
147 // Then we have to figure out if if we are ahead (+) or behind (-) UTC.
148 char sign_local_to_UTC = '+';
149 time_t abs_local_to_UTC = local_to_UTC;
150 if (local_to_UTC < 0) {
151 sign_local_to_UTC = '-';
152 abs_local_to_UTC = -(abs_local_to_UTC);
153 }
154 // Convert time zone offset seconds to hours and minutes.
155 const time_t zone_hours = (abs_local_to_UTC / seconds_per_hour);
156 const time_t zone_min =
157 ((abs_local_to_UTC % seconds_per_hour) / seconds_per_minute);
158
159 // Print an ISO 8601 date and time stamp into the buffer
160 const int year = 1900 + time_struct.tm_year;
161 const int month = 1 + time_struct.tm_mon;
162 const int printed = jio_snprintf(buffer, buffer_length,
163 "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d",
164 year,
165 month,
166 time_struct.tm_mday,
167 time_struct.tm_hour,
168 time_struct.tm_min,
169 time_struct.tm_sec,
170 milliseconds_after_second,
171 sign_local_to_UTC,
172 zone_hours,
173 zone_min);
174 if (printed == 0) {
175 assert(false, "Failed jio_printf");
176 return NULL;
177 }
178 return buffer;
179 }
180
181 OSReturn os::set_priority(Thread* thread, ThreadPriority p) {
182 #ifdef ASSERT
183 if (!(!thread->is_Java_thread() ||
184 Thread::current() == thread ||
185 Threads_lock->owned_by_self()
186 || thread->is_Compiler_thread()
187 )) {
188 assert(false, "possibility of dangling Thread pointer");
189 }
190 #endif
191
192 if (p >= MinPriority && p <= MaxPriority) {
193 int priority = java_to_os_priority[p];
194 return set_native_priority(thread, priority);
195 } else {
196 assert(false, "Should not happen");
197 return OS_ERR;
198 }
199 }
200
201 // The mapping from OS priority back to Java priority may be inexact because
202 // Java priorities can map M:1 with native priorities. If you want the definite
203 // Java priority then use JavaThread::java_priority()
204 OSReturn os::get_priority(const Thread* const thread, ThreadPriority& priority) {
205 int p;
206 int os_prio;
207 OSReturn ret = get_native_priority(thread, &os_prio);
208 if (ret != OS_OK) return ret;
209
210 if (java_to_os_priority[MaxPriority] > java_to_os_priority[MinPriority]) {
211 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] > os_prio; p--) ;
212 } else {
213 // niceness values are in reverse order
214 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] < os_prio; p--) ;
215 }
216 priority = (ThreadPriority)p;
217 return OS_OK;
218 }
219
220
221 // --------------------- sun.misc.Signal (optional) ---------------------
222
223
224 // SIGBREAK is sent by the keyboard to query the VM state
225 #ifndef SIGBREAK
226 #define SIGBREAK SIGQUIT
227 #endif
228
229 // sigexitnum_pd is a platform-specific special signal used for terminating the Signal thread.
230
231
232 static void signal_thread_entry(JavaThread* thread, TRAPS) {
233 os::set_priority(thread, NearMaxPriority);
234 while (true) {
235 int sig;
236 {
237 // FIXME : Currently we have not decided what should be the status
238 // for this java thread blocked here. Once we decide about
239 // that we should fix this.
240 sig = os::signal_wait();
241 }
242 if (sig == os::sigexitnum_pd()) {
243 // Terminate the signal thread
244 return;
245 }
246
247 switch (sig) {
248 case SIGBREAK: {
249 // Check if the signal is a trigger to start the Attach Listener - in that
250 // case don't print stack traces.
251 if (!DisableAttachMechanism && AttachListener::is_init_trigger()) {
252 continue;
253 }
254 // Print stack traces
255 // Any SIGBREAK operations added here should make sure to flush
256 // the output stream (e.g. tty->flush()) after output. See 4803766.
257 // Each module also prints an extra carriage return after its output.
258 VM_PrintThreads op;
259 VMThread::execute(&op);
260 VM_PrintJNI jni_op;
261 VMThread::execute(&jni_op);
262 VM_FindDeadlocks op1(tty);
263 VMThread::execute(&op1);
264 Universe::print_heap_at_SIGBREAK();
265 if (PrintClassHistogram) {
266 VM_GC_HeapInspection op1(tty, true /* force full GC before heap inspection */);
267 VMThread::execute(&op1);
268 }
269 if (JvmtiExport::should_post_data_dump()) {
270 JvmtiExport::post_data_dump();
271 }
272 break;
273 }
274 default: {
275 // Dispatch the signal to java
276 HandleMark hm(THREAD);
277 Klass* k = SystemDictionary::resolve_or_null(vmSymbols::jdk_internal_misc_Signal(), THREAD);
278 KlassHandle klass (THREAD, k);
279 if (klass.not_null()) {
280 JavaValue result(T_VOID);
281 JavaCallArguments args;
282 args.push_int(sig);
283 JavaCalls::call_static(
284 &result,
285 klass,
286 vmSymbols::dispatch_name(),
287 vmSymbols::int_void_signature(),
288 &args,
289 THREAD
290 );
291 }
292 if (HAS_PENDING_EXCEPTION) {
293 // tty is initialized early so we don't expect it to be null, but
294 // if it is we can't risk doing an initialization that might
295 // trigger additional out-of-memory conditions
296 if (tty != NULL) {
297 char klass_name[256];
298 char tmp_sig_name[16];
299 const char* sig_name = "UNKNOWN";
300 InstanceKlass::cast(PENDING_EXCEPTION->klass())->
301 name()->as_klass_external_name(klass_name, 256);
302 if (os::exception_name(sig, tmp_sig_name, 16) != NULL)
303 sig_name = tmp_sig_name;
304 warning("Exception %s occurred dispatching signal %s to handler"
305 "- the VM may need to be forcibly terminated",
306 klass_name, sig_name );
307 }
308 CLEAR_PENDING_EXCEPTION;
309 }
310 }
311 }
312 }
313 }
314
315 void os::init_before_ergo() {
316 // We need to initialize large page support here because ergonomics takes some
317 // decisions depending on large page support and the calculated large page size.
318 large_page_init();
319
320 // We need to adapt the configured number of stack protection pages given
321 // in 4K pages to the actual os page size. We must do this before setting
322 // up minimal stack sizes etc. in os::init_2().
323 JavaThread::set_stack_red_zone_size (align_size_up(StackRedPages * 4 * K, vm_page_size()));
324 JavaThread::set_stack_yellow_zone_size (align_size_up(StackYellowPages * 4 * K, vm_page_size()));
325 JavaThread::set_stack_reserved_zone_size(align_size_up(StackReservedPages * 4 * K, vm_page_size()));
326 JavaThread::set_stack_shadow_zone_size (align_size_up(StackShadowPages * 4 * K, vm_page_size()));
327
328 // VM version initialization identifies some characteristics of the
329 // platform that are used during ergonomic decisions.
330 VM_Version::init_before_ergo();
331 }
332
333 void os::signal_init() {
334 if (!ReduceSignalUsage) {
335 // Setup JavaThread for processing signals
336 EXCEPTION_MARK;
337 Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(), true, CHECK);
338 instanceKlassHandle klass (THREAD, k);
339 instanceHandle thread_oop = klass->allocate_instance_handle(CHECK);
340
341 const char thread_name[] = "Signal Dispatcher";
342 Handle string = java_lang_String::create_from_str(thread_name, CHECK);
343
344 // Initialize thread_oop to put it into the system threadGroup
345 Handle thread_group (THREAD, Universe::system_thread_group());
346 JavaValue result(T_VOID);
347 JavaCalls::call_special(&result, thread_oop,
348 klass,
349 vmSymbols::object_initializer_name(),
350 vmSymbols::threadgroup_string_void_signature(),
351 thread_group,
352 string,
353 CHECK);
354
355 KlassHandle group(THREAD, SystemDictionary::ThreadGroup_klass());
356 JavaCalls::call_special(&result,
357 thread_group,
358 group,
359 vmSymbols::add_method_name(),
360 vmSymbols::thread_void_signature(),
361 thread_oop, // ARG 1
362 CHECK);
363
364 os::signal_init_pd();
365
366 { MutexLocker mu(Threads_lock);
367 JavaThread* signal_thread = new JavaThread(&signal_thread_entry);
368
369 // At this point it may be possible that no osthread was created for the
370 // JavaThread due to lack of memory. We would have to throw an exception
371 // in that case. However, since this must work and we do not allow
372 // exceptions anyway, check and abort if this fails.
373 if (signal_thread == NULL || signal_thread->osthread() == NULL) {
374 vm_exit_during_initialization("java.lang.OutOfMemoryError",
375 os::native_thread_creation_failed_msg());
376 }
377
378 java_lang_Thread::set_thread(thread_oop(), signal_thread);
379 java_lang_Thread::set_priority(thread_oop(), NearMaxPriority);
380 java_lang_Thread::set_daemon(thread_oop());
381
382 signal_thread->set_threadObj(thread_oop());
383 Threads::add(signal_thread);
384 Thread::start(signal_thread);
385 }
386 // Handle ^BREAK
387 os::signal(SIGBREAK, os::user_handler());
388 }
389 }
390
391
392 void os::terminate_signal_thread() {
393 if (!ReduceSignalUsage)
394 signal_notify(sigexitnum_pd());
395 }
396
397
398 // --------------------- loading libraries ---------------------
399
400 typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *);
401 extern struct JavaVM_ main_vm;
402
403 static void* _native_java_library = NULL;
404
405 void* os::native_java_library() {
406 if (_native_java_library == NULL) {
407 char buffer[JVM_MAXPATHLEN];
408 char ebuf[1024];
409
410 // Try to load verify dll first. In 1.3 java dll depends on it and is not
411 // always able to find it when the loading executable is outside the JDK.
412 // In order to keep working with 1.2 we ignore any loading errors.
413 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
414 "verify")) {
415 dll_load(buffer, ebuf, sizeof(ebuf));
416 }
417
418 // Load java dll
419 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
420 "java")) {
421 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf));
422 }
423 if (_native_java_library == NULL) {
424 vm_exit_during_initialization("Unable to load native library", ebuf);
425 }
426
427 #if defined(__OpenBSD__)
428 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so
429 // ignore errors
430 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
431 "net")) {
432 dll_load(buffer, ebuf, sizeof(ebuf));
433 }
434 #endif
435 }
436 return _native_java_library;
437 }
438
439 /*
440 * Support for finding Agent_On(Un)Load/Attach<_lib_name> if it exists.
441 * If check_lib == true then we are looking for an
442 * Agent_OnLoad_lib_name or Agent_OnAttach_lib_name function to determine if
443 * this library is statically linked into the image.
444 * If check_lib == false then we will look for the appropriate symbol in the
445 * executable if agent_lib->is_static_lib() == true or in the shared library
446 * referenced by 'handle'.
447 */
448 void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib,
449 const char *syms[], size_t syms_len) {
450 assert(agent_lib != NULL, "sanity check");
451 const char *lib_name;
452 void *handle = agent_lib->os_lib();
453 void *entryName = NULL;
454 char *agent_function_name;
455 size_t i;
456
457 // If checking then use the agent name otherwise test is_static_lib() to
458 // see how to process this lookup
459 lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL);
460 for (i = 0; i < syms_len; i++) {
461 agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path());
462 if (agent_function_name == NULL) {
463 break;
464 }
465 entryName = dll_lookup(handle, agent_function_name);
466 FREE_C_HEAP_ARRAY(char, agent_function_name);
467 if (entryName != NULL) {
468 break;
469 }
470 }
471 return entryName;
472 }
473
474 // See if the passed in agent is statically linked into the VM image.
475 bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
476 size_t syms_len) {
477 void *ret;
478 void *proc_handle;
479 void *save_handle;
480
481 assert(agent_lib != NULL, "sanity check");
482 if (agent_lib->name() == NULL) {
483 return false;
484 }
485 proc_handle = get_default_process_handle();
486 // Check for Agent_OnLoad/Attach_lib_name function
487 save_handle = agent_lib->os_lib();
488 // We want to look in this process' symbol table.
489 agent_lib->set_os_lib(proc_handle);
490 ret = find_agent_function(agent_lib, true, syms, syms_len);
491 if (ret != NULL) {
492 // Found an entry point like Agent_OnLoad_lib_name so we have a static agent
493 agent_lib->set_valid();
494 agent_lib->set_static_lib(true);
495 return true;
496 }
497 agent_lib->set_os_lib(save_handle);
498 return false;
499 }
500
501 // --------------------- heap allocation utilities ---------------------
502
503 char *os::strdup(const char *str, MEMFLAGS flags) {
504 size_t size = strlen(str);
505 char *dup_str = (char *)malloc(size + 1, flags);
506 if (dup_str == NULL) return NULL;
507 strcpy(dup_str, str);
508 return dup_str;
509 }
510
511 char* os::strdup_check_oom(const char* str, MEMFLAGS flags) {
512 char* p = os::strdup(str, flags);
513 if (p == NULL) {
514 vm_exit_out_of_memory(strlen(str) + 1, OOM_MALLOC_ERROR, "os::strdup_check_oom");
515 }
516 return p;
517 }
518
519
520 #define paranoid 0 /* only set to 1 if you suspect checking code has bug */
521
522 #ifdef ASSERT
523
524 static void verify_memory(void* ptr) {
525 GuardedMemory guarded(ptr);
526 if (!guarded.verify_guards()) {
527 tty->print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees);
528 tty->print_cr("## memory stomp:");
529 guarded.print_on(tty);
530 fatal("memory stomping error");
531 }
532 }
533
534 #endif
535
536 //
537 // This function supports testing of the malloc out of memory
538 // condition without really running the system out of memory.
539 //
540 static bool has_reached_max_malloc_test_peak(size_t alloc_size) {
541 if (MallocMaxTestWords > 0) {
542 jint words = (jint)(alloc_size / BytesPerWord);
543
544 if ((cur_malloc_words + words) > MallocMaxTestWords) {
545 return true;
546 }
547 Atomic::add(words, (volatile jint *)&cur_malloc_words);
548 }
549 return false;
550 }
551
552 void* os::malloc(size_t size, MEMFLAGS flags) {
553 return os::malloc(size, flags, CALLER_PC);
554 }
555
556 void* os::malloc(size_t size, MEMFLAGS memflags, const NativeCallStack& stack) {
557 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
558 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
559
560 #ifdef ASSERT
561 // checking for the WatcherThread and crash_protection first
562 // since os::malloc can be called when the libjvm.{dll,so} is
563 // first loaded and we don't have a thread yet.
564 // try to find the thread after we see that the watcher thread
565 // exists and has crash protection.
566 WatcherThread *wt = WatcherThread::watcher_thread();
567 if (wt != NULL && wt->has_crash_protection()) {
568 Thread* thread = Thread::current_or_null();
569 if (thread == wt) {
570 assert(!wt->has_crash_protection(),
571 "Can't malloc with crash protection from WatcherThread");
572 }
573 }
574 #endif
575
576 if (size == 0) {
577 // return a valid pointer if size is zero
578 // if NULL is returned the calling functions assume out of memory.
579 size = 1;
580 }
581
582 // NMT support
583 NMT_TrackingLevel level = MemTracker::tracking_level();
584 size_t nmt_header_size = MemTracker::malloc_header_size(level);
585
586 #ifndef ASSERT
587 const size_t alloc_size = size + nmt_header_size;
588 #else
589 const size_t alloc_size = GuardedMemory::get_total_size(size + nmt_header_size);
590 if (size + nmt_header_size > alloc_size) { // Check for rollover.
591 return NULL;
592 }
593 #endif
594
595 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
596
597 // For the test flag -XX:MallocMaxTestWords
598 if (has_reached_max_malloc_test_peak(size)) {
599 return NULL;
600 }
601
602 u_char* ptr;
603 ptr = (u_char*)::malloc(alloc_size);
604
605 #ifdef ASSERT
606 if (ptr == NULL) {
607 return NULL;
608 }
609 // Wrap memory with guard
610 GuardedMemory guarded(ptr, size + nmt_header_size);
611 ptr = guarded.get_user_ptr();
612 #endif
613 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) {
614 tty->print_cr("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr));
615 breakpoint();
616 }
617 debug_only(if (paranoid) verify_memory(ptr));
618 if (PrintMalloc && tty != NULL) {
619 tty->print_cr("os::malloc " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr));
620 }
621
622 // we do not track guard memory
623 return MemTracker::record_malloc((address)ptr, size, memflags, stack, level);
624 }
625
626 void* os::realloc(void *memblock, size_t size, MEMFLAGS flags) {
627 return os::realloc(memblock, size, flags, CALLER_PC);
628 }
629
630 void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, const NativeCallStack& stack) {
631
632 // For the test flag -XX:MallocMaxTestWords
633 if (has_reached_max_malloc_test_peak(size)) {
634 return NULL;
635 }
636
637 #ifndef ASSERT
638 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
639 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
640 // NMT support
641 void* membase = MemTracker::record_free(memblock);
642 NMT_TrackingLevel level = MemTracker::tracking_level();
643 size_t nmt_header_size = MemTracker::malloc_header_size(level);
644 void* ptr = ::realloc(membase, size + nmt_header_size);
645 return MemTracker::record_malloc(ptr, size, memflags, stack, level);
646 #else
647 if (memblock == NULL) {
648 return os::malloc(size, memflags, stack);
649 }
650 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
651 tty->print_cr("os::realloc caught " PTR_FORMAT, p2i(memblock));
652 breakpoint();
653 }
654 // NMT support
655 void* membase = MemTracker::malloc_base(memblock);
656 verify_memory(membase);
657 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
658 if (size == 0) {
659 return NULL;
660 }
661 // always move the block
662 void* ptr = os::malloc(size, memflags, stack);
663 if (PrintMalloc && tty != NULL) {
664 tty->print_cr("os::realloc " SIZE_FORMAT " bytes, " PTR_FORMAT " --> " PTR_FORMAT, size, p2i(memblock), p2i(ptr));
665 }
666 // Copy to new memory if malloc didn't fail
667 if ( ptr != NULL ) {
668 GuardedMemory guarded(MemTracker::malloc_base(memblock));
669 // Guard's user data contains NMT header
670 size_t memblock_size = guarded.get_user_size() - MemTracker::malloc_header_size(memblock);
671 memcpy(ptr, memblock, MIN2(size, memblock_size));
672 if (paranoid) verify_memory(MemTracker::malloc_base(ptr));
673 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) {
674 tty->print_cr("os::realloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr));
675 breakpoint();
676 }
677 os::free(memblock);
678 }
679 return ptr;
680 #endif
681 }
682
683
684 void os::free(void *memblock) {
685 NOT_PRODUCT(inc_stat_counter(&num_frees, 1));
686 #ifdef ASSERT
687 if (memblock == NULL) return;
688 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
689 if (tty != NULL) tty->print_cr("os::free caught " PTR_FORMAT, p2i(memblock));
690 breakpoint();
691 }
692 void* membase = MemTracker::record_free(memblock);
693 verify_memory(membase);
694 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
695
696 GuardedMemory guarded(membase);
697 size_t size = guarded.get_user_size();
698 inc_stat_counter(&free_bytes, size);
699 membase = guarded.release_for_freeing();
700 if (PrintMalloc && tty != NULL) {
701 fprintf(stderr, "os::free " SIZE_FORMAT " bytes --> " PTR_FORMAT "\n", size, (uintptr_t)membase);
702 }
703 ::free(membase);
704 #else
705 void* membase = MemTracker::record_free(memblock);
706 ::free(membase);
707 #endif
708 }
709
710 void os::init_random(long initval) {
711 _rand_seed = initval;
712 }
713
714
715 long os::random() {
716 /* standard, well-known linear congruential random generator with
717 * next_rand = (16807*seed) mod (2**31-1)
718 * see
719 * (1) "Random Number Generators: Good Ones Are Hard to Find",
720 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988),
721 * (2) "Two Fast Implementations of the 'Minimal Standard' Random
722 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88.
723 */
724 const long a = 16807;
725 const unsigned long m = 2147483647;
726 const long q = m / a; assert(q == 127773, "weird math");
727 const long r = m % a; assert(r == 2836, "weird math");
728
729 // compute az=2^31p+q
730 unsigned long lo = a * (long)(_rand_seed & 0xFFFF);
731 unsigned long hi = a * (long)((unsigned long)_rand_seed >> 16);
732 lo += (hi & 0x7FFF) << 16;
733
734 // if q overflowed, ignore the overflow and increment q
735 if (lo > m) {
736 lo &= m;
737 ++lo;
738 }
739 lo += hi >> 15;
740
741 // if (p+q) overflowed, ignore the overflow and increment (p+q)
742 if (lo > m) {
743 lo &= m;
744 ++lo;
745 }
746 return (_rand_seed = lo);
747 }
748
749 // The INITIALIZED state is distinguished from the SUSPENDED state because the
750 // conditions in which a thread is first started are different from those in which
751 // a suspension is resumed. These differences make it hard for us to apply the
752 // tougher checks when starting threads that we want to do when resuming them.
753 // However, when start_thread is called as a result of Thread.start, on a Java
754 // thread, the operation is synchronized on the Java Thread object. So there
755 // cannot be a race to start the thread and hence for the thread to exit while
756 // we are working on it. Non-Java threads that start Java threads either have
757 // to do so in a context in which races are impossible, or should do appropriate
758 // locking.
759
760 void os::start_thread(Thread* thread) {
761 // guard suspend/resume
762 MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag);
763 OSThread* osthread = thread->osthread();
764 osthread->set_state(RUNNABLE);
765 pd_start_thread(thread);
766 }
767
768 void os::abort(bool dump_core) {
769 abort(dump_core && CreateCoredumpOnCrash, NULL, NULL);
770 }
771
772 //---------------------------------------------------------------------------
773 // Helper functions for fatal error handler
774
775 void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) {
776 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking");
777
778 int cols = 0;
779 int cols_per_line = 0;
780 switch (unitsize) {
781 case 1: cols_per_line = 16; break;
782 case 2: cols_per_line = 8; break;
783 case 4: cols_per_line = 4; break;
784 case 8: cols_per_line = 2; break;
785 default: return;
786 }
787
788 address p = start;
789 st->print(PTR_FORMAT ": ", p2i(start));
790 while (p < end) {
791 switch (unitsize) {
792 case 1: st->print("%02x", *(u1*)p); break;
793 case 2: st->print("%04x", *(u2*)p); break;
794 case 4: st->print("%08x", *(u4*)p); break;
795 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break;
796 }
797 p += unitsize;
798 cols++;
799 if (cols >= cols_per_line && p < end) {
800 cols = 0;
801 st->cr();
802 st->print(PTR_FORMAT ": ", p2i(p));
803 } else {
804 st->print(" ");
805 }
806 }
807 st->cr();
808 }
809
810 void os::print_environment_variables(outputStream* st, const char** env_list) {
811 if (env_list) {
812 st->print_cr("Environment Variables:");
813
814 for (int i = 0; env_list[i] != NULL; i++) {
815 char *envvar = ::getenv(env_list[i]);
816 if (envvar != NULL) {
817 st->print("%s", env_list[i]);
818 st->print("=");
819 st->print_cr("%s", envvar);
820 }
821 }
822 }
823 }
824
825 void os::print_cpu_info(outputStream* st, char* buf, size_t buflen) {
826 // cpu
827 st->print("CPU:");
828 st->print("total %d", os::processor_count());
829 // It's not safe to query number of active processors after crash
830 // st->print("(active %d)", os::active_processor_count());
831 st->print(" %s", VM_Version::features_string());
832 st->cr();
833 pd_print_cpu_info(st, buf, buflen);
834 }
835
836 // Print a one line string summarizing the cpu, number of cores, memory, and operating system version
837 void os::print_summary_info(outputStream* st, char* buf, size_t buflen) {
838 st->print("Host: ");
839 #ifndef PRODUCT
840 if (get_host_name(buf, buflen)) {
841 st->print("%s, ", buf);
842 }
843 #endif // PRODUCT
844 get_summary_cpu_info(buf, buflen);
845 st->print("%s, ", buf);
846 size_t mem = physical_memory()/G;
847 if (mem == 0) { // for low memory systems
848 mem = physical_memory()/M;
849 st->print("%d cores, " SIZE_FORMAT "M, ", processor_count(), mem);
850 } else {
851 st->print("%d cores, " SIZE_FORMAT "G, ", processor_count(), mem);
852 }
853 get_summary_os_info(buf, buflen);
854 st->print_raw(buf);
855 st->cr();
856 }
857
858 void os::print_date_and_time(outputStream *st, char* buf, size_t buflen) {
859 const int secs_per_day = 86400;
860 const int secs_per_hour = 3600;
861 const int secs_per_min = 60;
862
863 time_t tloc;
864 (void)time(&tloc);
865 char* timestring = ctime(&tloc); // ctime adds newline.
866 // edit out the newline
867 char* nl = strchr(timestring, '\n');
868 if (nl != NULL) {
869 *nl = '\0';
870 }
871
872 struct tm tz;
873 if (localtime_pd(&tloc, &tz) != NULL) {
874 ::strftime(buf, buflen, "%Z", &tz);
875 st->print("Time: %s %s", timestring, buf);
876 } else {
877 st->print("Time: %s", timestring);
878 }
879
880 double t = os::elapsedTime();
881 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in
882 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int
883 // before printf. We lost some precision, but who cares?
884 int eltime = (int)t; // elapsed time in seconds
885
886 // print elapsed time in a human-readable format:
887 int eldays = eltime / secs_per_day;
888 int day_secs = eldays * secs_per_day;
889 int elhours = (eltime - day_secs) / secs_per_hour;
890 int hour_secs = elhours * secs_per_hour;
891 int elmins = (eltime - day_secs - hour_secs) / secs_per_min;
892 int minute_secs = elmins * secs_per_min;
893 int elsecs = (eltime - day_secs - hour_secs - minute_secs);
894 st->print_cr(" elapsed time: %d seconds (%dd %dh %dm %ds)", eltime, eldays, elhours, elmins, elsecs);
895 }
896
897 // moved from debug.cpp (used to be find()) but still called from there
898 // The verbose parameter is only set by the debug code in one case
899 void os::print_location(outputStream* st, intptr_t x, bool verbose) {
900 address addr = (address)x;
901 CodeBlob* b = CodeCache::find_blob_unsafe(addr);
902 if (b != NULL) {
903 if (b->is_buffer_blob()) {
904 // the interpreter is generated into a buffer blob
905 InterpreterCodelet* i = Interpreter::codelet_containing(addr);
906 if (i != NULL) {
907 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an Interpreter codelet", p2i(addr), (int)(addr - i->code_begin()));
908 i->print_on(st);
909 return;
910 }
911 if (Interpreter::contains(addr)) {
912 st->print_cr(INTPTR_FORMAT " is pointing into interpreter code"
913 " (not bytecode specific)", p2i(addr));
914 return;
915 }
916 //
917 if (AdapterHandlerLibrary::contains(b)) {
918 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an AdapterHandler", p2i(addr), (int)(addr - b->code_begin()));
919 AdapterHandlerLibrary::print_handler_on(st, b);
920 }
921 // the stubroutines are generated into a buffer blob
922 StubCodeDesc* d = StubCodeDesc::desc_for(addr);
923 if (d != NULL) {
924 st->print_cr(INTPTR_FORMAT " is at begin+%d in a stub", p2i(addr), (int)(addr - d->begin()));
925 d->print_on(st);
926 st->cr();
927 return;
928 }
929 if (StubRoutines::contains(addr)) {
930 st->print_cr(INTPTR_FORMAT " is pointing to an (unnamed) stub routine", p2i(addr));
931 return;
932 }
933 // the InlineCacheBuffer is using stubs generated into a buffer blob
934 if (InlineCacheBuffer::contains(addr)) {
935 st->print_cr(INTPTR_FORMAT " is pointing into InlineCacheBuffer", p2i(addr));
936 return;
937 }
938 VtableStub* v = VtableStubs::stub_containing(addr);
939 if (v != NULL) {
940 st->print_cr(INTPTR_FORMAT " is at entry_point+%d in a vtable stub", p2i(addr), (int)(addr - v->entry_point()));
941 v->print_on(st);
942 st->cr();
943 return;
944 }
945 }
946 nmethod* nm = b->as_nmethod_or_null();
947 if (nm != NULL) {
948 ResourceMark rm;
949 st->print(INTPTR_FORMAT " is at entry_point+%d in (nmethod*)" INTPTR_FORMAT,
950 p2i(addr), (int)(addr - nm->entry_point()), p2i(nm));
951 if (verbose) {
952 st->print(" for ");
953 nm->method()->print_value_on(st);
954 }
955 st->cr();
956 nm->print_nmethod(verbose);
957 return;
958 }
959 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in ", p2i(addr), (int)(addr - b->code_begin()));
960 b->print_on(st);
961 return;
962 }
963
964 if (Universe::heap()->is_in(addr)) {
965 HeapWord* p = Universe::heap()->block_start(addr);
966 bool print = false;
967 // If we couldn't find it it just may mean that heap wasn't parsable
968 // See if we were just given an oop directly
969 if (p != NULL && Universe::heap()->block_is_obj(p)) {
970 print = true;
971 } else if (p == NULL && ((oopDesc*)addr)->is_oop()) {
972 p = (HeapWord*) addr;
973 print = true;
974 }
975 if (print) {
976 if (p == (HeapWord*) addr) {
977 st->print_cr(INTPTR_FORMAT " is an oop", p2i(addr));
978 } else {
979 st->print_cr(INTPTR_FORMAT " is pointing into object: " INTPTR_FORMAT, p2i(addr), p2i(p));
980 }
981 oop(p)->print_on(st);
982 return;
983 }
984 } else {
985 if (Universe::heap()->is_in_reserved(addr)) {
986 st->print_cr(INTPTR_FORMAT " is an unallocated location "
987 "in the heap", p2i(addr));
988 return;
989 }
990 }
991 if (JNIHandles::is_global_handle((jobject) addr)) {
992 st->print_cr(INTPTR_FORMAT " is a global jni handle", p2i(addr));
993 return;
994 }
995 if (JNIHandles::is_weak_global_handle((jobject) addr)) {
996 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", p2i(addr));
997 return;
998 }
999 #ifndef PRODUCT
1000 // we don't keep the block list in product mode
1001 if (JNIHandleBlock::any_contains((jobject) addr)) {
1002 st->print_cr(INTPTR_FORMAT " is a local jni handle", p2i(addr));
1003 return;
1004 }
1005 #endif
1006
1007 for(JavaThread *thread = Threads::first(); thread; thread = thread->next()) {
1008 // Check for privilege stack
1009 if (thread->privileged_stack_top() != NULL &&
1010 thread->privileged_stack_top()->contains(addr)) {
1011 st->print_cr(INTPTR_FORMAT " is pointing into the privilege stack "
1012 "for thread: " INTPTR_FORMAT, p2i(addr), p2i(thread));
1013 if (verbose) thread->print_on(st);
1014 return;
1015 }
1016 // If the addr is a java thread print information about that.
1017 if (addr == (address)thread) {
1018 if (verbose) {
1019 thread->print_on(st);
1020 } else {
1021 st->print_cr(INTPTR_FORMAT " is a thread", p2i(addr));
1022 }
1023 return;
1024 }
1025 // If the addr is in the stack region for this thread then report that
1026 // and print thread info
1027 if (thread->on_local_stack(addr)) {
1028 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: "
1029 INTPTR_FORMAT, p2i(addr), p2i(thread));
1030 if (verbose) thread->print_on(st);
1031 return;
1032 }
1033
1034 }
1035
1036 // Check if in metaspace and print types that have vptrs (only method now)
1037 if (Metaspace::contains(addr)) {
1038 if (Method::has_method_vptr((const void*)addr)) {
1039 ((Method*)addr)->print_value_on(st);
1040 st->cr();
1041 } else {
1042 // Use addr->print() from the debugger instead (not here)
1043 st->print_cr(INTPTR_FORMAT " is pointing into metadata", p2i(addr));
1044 }
1045 return;
1046 }
1047
1048 // Try an OS specific find
1049 if (os::find(addr, st)) {
1050 return;
1051 }
1052
1053 st->print_cr(INTPTR_FORMAT " is an unknown value", p2i(addr));
1054 }
1055
1056 // Looks like all platforms except IA64 can use the same function to check
1057 // if C stack is walkable beyond current frame. The check for fp() is not
1058 // necessary on Sparc, but it's harmless.
1059 bool os::is_first_C_frame(frame* fr) {
1060 #if (defined(IA64) && !defined(AIX)) && !defined(_WIN32)
1061 // On IA64 we have to check if the callers bsp is still valid
1062 // (i.e. within the register stack bounds).
1063 // Notice: this only works for threads created by the VM and only if
1064 // we walk the current stack!!! If we want to be able to walk
1065 // arbitrary other threads, we'll have to somehow store the thread
1066 // object in the frame.
1067 Thread *thread = Thread::current();
1068 if ((address)fr->fp() <=
1069 thread->register_stack_base() HPUX_ONLY(+ 0x0) LINUX_ONLY(+ 0x50)) {
1070 // This check is a little hacky, because on Linux the first C
1071 // frame's ('start_thread') register stack frame starts at
1072 // "register_stack_base + 0x48" while on HPUX, the first C frame's
1073 // ('__pthread_bound_body') register stack frame seems to really
1074 // start at "register_stack_base".
1075 return true;
1076 } else {
1077 return false;
1078 }
1079 #elif defined(IA64) && defined(_WIN32)
1080 return true;
1081 #else
1082 // Load up sp, fp, sender sp and sender fp, check for reasonable values.
1083 // Check usp first, because if that's bad the other accessors may fault
1084 // on some architectures. Ditto ufp second, etc.
1085 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1);
1086 // sp on amd can be 32 bit aligned.
1087 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1);
1088
1089 uintptr_t usp = (uintptr_t)fr->sp();
1090 if ((usp & sp_align_mask) != 0) return true;
1091
1092 uintptr_t ufp = (uintptr_t)fr->fp();
1093 if ((ufp & fp_align_mask) != 0) return true;
1094
1095 uintptr_t old_sp = (uintptr_t)fr->sender_sp();
1096 if ((old_sp & sp_align_mask) != 0) return true;
1097 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true;
1098
1099 uintptr_t old_fp = (uintptr_t)fr->link();
1100 if ((old_fp & fp_align_mask) != 0) return true;
1101 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true;
1102
1103 // stack grows downwards; if old_fp is below current fp or if the stack
1104 // frame is too large, either the stack is corrupted or fp is not saved
1105 // on stack (i.e. on x86, ebp may be used as general register). The stack
1106 // is not walkable beyond current frame.
1107 if (old_fp < ufp) return true;
1108 if (old_fp - ufp > 64 * K) return true;
1109
1110 return false;
1111 #endif
1112 }
1113
1114 #ifdef ASSERT
1115 extern "C" void test_random() {
1116 const double m = 2147483647;
1117 double mean = 0.0, variance = 0.0, t;
1118 long reps = 10000;
1119 unsigned long seed = 1;
1120
1121 tty->print_cr("seed %ld for %ld repeats...", seed, reps);
1122 os::init_random(seed);
1123 long num;
1124 for (int k = 0; k < reps; k++) {
1125 num = os::random();
1126 double u = (double)num / m;
1127 assert(u >= 0.0 && u <= 1.0, "bad random number!");
1128
1129 // calculate mean and variance of the random sequence
1130 mean += u;
1131 variance += (u*u);
1132 }
1133 mean /= reps;
1134 variance /= (reps - 1);
1135
1136 assert(num == 1043618065, "bad seed");
1137 tty->print_cr("mean of the 1st 10000 numbers: %f", mean);
1138 tty->print_cr("variance of the 1st 10000 numbers: %f", variance);
1139 const double eps = 0.0001;
1140 t = fabsd(mean - 0.5018);
1141 assert(t < eps, "bad mean");
1142 t = (variance - 0.3355) < 0.0 ? -(variance - 0.3355) : variance - 0.3355;
1143 assert(t < eps, "bad variance");
1144 }
1145 #endif
1146
1147
1148 // Set up the boot classpath.
1149
1150 char* os::format_boot_path(const char* format_string,
1151 const char* home,
1152 int home_len,
1153 char fileSep,
1154 char pathSep) {
1155 assert((fileSep == '/' && pathSep == ':') ||
1156 (fileSep == '\\' && pathSep == ';'), "unexpected separator chars");
1157
1158 // Scan the format string to determine the length of the actual
1159 // boot classpath, and handle platform dependencies as well.
1160 int formatted_path_len = 0;
1161 const char* p;
1162 for (p = format_string; *p != 0; ++p) {
1163 if (*p == '%') formatted_path_len += home_len - 1;
1164 ++formatted_path_len;
1165 }
1166
1167 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal);
1168 if (formatted_path == NULL) {
1169 return NULL;
1170 }
1171
1172 // Create boot classpath from format, substituting separator chars and
1173 // java home directory.
1174 char* q = formatted_path;
1175 for (p = format_string; *p != 0; ++p) {
1176 switch (*p) {
1177 case '%':
1178 strcpy(q, home);
1179 q += home_len;
1180 break;
1181 case '/':
1182 *q++ = fileSep;
1183 break;
1184 case ':':
1185 *q++ = pathSep;
1186 break;
1187 default:
1188 *q++ = *p;
1189 }
1190 }
1191 *q = '\0';
1192
1193 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched");
1194 return formatted_path;
1195 }
1196
1197 // returns a PATH of all entries in the given directory that do not start with a '.'
1198 static char* expand_entries_to_path(char* directory, char fileSep, char pathSep) {
1199 DIR* dir = os::opendir(directory);
1200 if (dir == NULL) return NULL;
1201
1202 char* path = NULL;
1203 size_t path_len = 0; // path length including \0 terminator
1204
1205 size_t directory_len = strlen(directory);
1206 struct dirent *entry;
1207 char* dbuf = NEW_C_HEAP_ARRAY(char, os::readdir_buf_size(directory), mtInternal);
1208 while ((entry = os::readdir(dir, (dirent *) dbuf)) != NULL) {
1209 const char* name = entry->d_name;
1210 if (name[0] == '.') continue;
1211
1212 size_t name_len = strlen(name);
1213 size_t needed = directory_len + name_len + 2;
1214 size_t new_len = path_len + needed;
1215 if (path == NULL) {
1216 path = NEW_C_HEAP_ARRAY(char, new_len, mtInternal);
1217 } else {
1218 path = REALLOC_C_HEAP_ARRAY(char, path, new_len, mtInternal);
1219 }
1220 if (path == NULL)
1221 break;
1222
1223 // append <pathSep>directory<fileSep>name
1224 char* p = path;
1225 if (path_len > 0) {
1226 p += (path_len -1);
1227 *p = pathSep;
1228 p++;
1229 }
1230
1231 strcpy(p, directory);
1232 p += directory_len;
1233
1234 *p = fileSep;
1235 p++;
1236
1237 strcpy(p, name);
1238 p += name_len;
1239
1240 path_len = new_len;
1241 }
1242
1243 FREE_C_HEAP_ARRAY(char, dbuf);
1244 os::closedir(dir);
1245
1246 return path;
1247 }
1248
1249 bool os::set_boot_path(char fileSep, char pathSep) {
1250 const char* home = Arguments::get_java_home();
1251 int home_len = (int)strlen(home);
1252
1253 char* sysclasspath = NULL;
1254 struct stat st;
1255
1256 // modular image if bootmodules.jimage exists
1257 char* jimage = format_boot_path("%/lib/modules/" BOOT_IMAGE_NAME, home, home_len, fileSep, pathSep);
1258 if (jimage == NULL) return false;
1259 bool has_jimage = (os::stat(jimage, &st) == 0);
1260 if (has_jimage) {
1261 Arguments::set_sysclasspath(jimage);
1262 FREE_C_HEAP_ARRAY(char, jimage);
1263 return true;
1264 }
1265 FREE_C_HEAP_ARRAY(char, jimage);
1266
1267 // check if developer build with exploded modules
1268 char* modules_dir = format_boot_path("%/modules", home, home_len, fileSep, pathSep);
1269 if (os::stat(modules_dir, &st) == 0) {
1270 if ((st.st_mode & S_IFDIR) == S_IFDIR) {
1271 sysclasspath = expand_entries_to_path(modules_dir, fileSep, pathSep);
1272 }
1273 }
1274 FREE_C_HEAP_ARRAY(char, modules_dir);
1275
1276 // fallback to classes
1277 if (sysclasspath == NULL)
1278 sysclasspath = format_boot_path("%/classes", home, home_len, fileSep, pathSep);
1279
1280 if (sysclasspath == NULL) return false;
1281 Arguments::set_sysclasspath(sysclasspath);
1282 FREE_C_HEAP_ARRAY(char, sysclasspath);
1283
1284 return true;
1285 }
1286
1287 /*
1288 * Splits a path, based on its separator, the number of
1289 * elements is returned back in n.
1290 * It is the callers responsibility to:
1291 * a> check the value of n, and n may be 0.
1292 * b> ignore any empty path elements
1293 * c> free up the data.
1294 */
1295 char** os::split_path(const char* path, int* n) {
1296 *n = 0;
1297 if (path == NULL || strlen(path) == 0) {
1298 return NULL;
1299 }
1300 const char psepchar = *os::path_separator();
1301 char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal);
1302 if (inpath == NULL) {
1303 return NULL;
1304 }
1305 strcpy(inpath, path);
1306 int count = 1;
1307 char* p = strchr(inpath, psepchar);
1308 // Get a count of elements to allocate memory
1309 while (p != NULL) {
1310 count++;
1311 p++;
1312 p = strchr(p, psepchar);
1313 }
1314 char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count, mtInternal);
1315 if (opath == NULL) {
1316 return NULL;
1317 }
1318
1319 // do the actual splitting
1320 p = inpath;
1321 for (int i = 0 ; i < count ; i++) {
1322 size_t len = strcspn(p, os::path_separator());
1323 if (len > JVM_MAXPATHLEN) {
1324 return NULL;
1325 }
1326 // allocate the string and add terminator storage
1327 char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
1328 if (s == NULL) {
1329 return NULL;
1330 }
1331 strncpy(s, p, len);
1332 s[len] = '\0';
1333 opath[i] = s;
1334 p += len + 1;
1335 }
1336 FREE_C_HEAP_ARRAY(char, inpath);
1337 *n = count;
1338 return opath;
1339 }
1340
1341 void os::set_memory_serialize_page(address page) {
1342 int count = log2_intptr(sizeof(class JavaThread)) - log2_intptr(64);
1343 _mem_serialize_page = (volatile int32_t *)page;
1344 // We initialize the serialization page shift count here
1345 // We assume a cache line size of 64 bytes
1346 assert(SerializePageShiftCount == count,
1347 "thread size changed, fix SerializePageShiftCount constant");
1348 set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t)));
1349 }
1350
1351 static volatile intptr_t SerializePageLock = 0;
1352
1353 // This method is called from signal handler when SIGSEGV occurs while the current
1354 // thread tries to store to the "read-only" memory serialize page during state
1355 // transition.
1356 void os::block_on_serialize_page_trap() {
1357 log_debug(safepoint)("Block until the serialize page permission restored");
1358
1359 // When VMThread is holding the SerializePageLock during modifying the
1360 // access permission of the memory serialize page, the following call
1361 // will block until the permission of that page is restored to rw.
1362 // Generally, it is unsafe to manipulate locks in signal handlers, but in
1363 // this case, it's OK as the signal is synchronous and we know precisely when
1364 // it can occur.
1365 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page");
1366 Thread::muxRelease(&SerializePageLock);
1367 }
1368
1369 // Serialize all thread state variables
1370 void os::serialize_thread_states() {
1371 // On some platforms such as Solaris & Linux, the time duration of the page
1372 // permission restoration is observed to be much longer than expected due to
1373 // scheduler starvation problem etc. To avoid the long synchronization
1374 // time and expensive page trap spinning, 'SerializePageLock' is used to block
1375 // the mutator thread if such case is encountered. See bug 6546278 for details.
1376 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states");
1377 os::protect_memory((char *)os::get_memory_serialize_page(),
1378 os::vm_page_size(), MEM_PROT_READ);
1379 os::protect_memory((char *)os::get_memory_serialize_page(),
1380 os::vm_page_size(), MEM_PROT_RW);
1381 Thread::muxRelease(&SerializePageLock);
1382 }
1383
1384 // Returns true if the current stack pointer is above the stack shadow
1385 // pages, false otherwise.
1386 bool os::stack_shadow_pages_available(Thread *thread, const methodHandle& method) {
1387 if (!thread->is_Java_thread()) return false;
1388 address sp = current_stack_pointer();
1389 // Check if we have StackShadowPages above the yellow zone. This parameter
1390 // is dependent on the depth of the maximum VM call stack possible from
1391 // the handler for stack overflow. 'instanceof' in the stack overflow
1392 // handler or a println uses at least 8k stack of VM and native code
1393 // respectively.
1394 const int framesize_in_bytes =
1395 Interpreter::size_top_interpreter_activation(method()) * wordSize;
1396
1397 assert((thread->stack_base() - thread->stack_size()) +
1398 (JavaThread::stack_guard_zone_size() +
1399 JavaThread::stack_shadow_zone_size() + framesize_in_bytes) ==
1400 ((JavaThread*)thread)->stack_overflow_limit() + framesize_in_bytes, "sanity");
1401
1402 return (sp > ((JavaThread*)thread)->stack_overflow_limit() + framesize_in_bytes);
1403 }
1404
1405 size_t os::page_size_for_region(size_t region_size, size_t min_pages, bool must_be_aligned) {
1406 assert(min_pages > 0, "sanity");
1407 if (UseLargePages) {
1408 const size_t max_page_size = region_size / min_pages;
1409
1410 for (size_t i = 0; _page_sizes[i] != 0; ++i) {
1411 const size_t page_size = _page_sizes[i];
1412 if (page_size <= max_page_size) {
1413 if (!must_be_aligned || is_size_aligned(region_size, page_size)) {
1414 return page_size;
1415 }
1416 }
1417 }
1418 }
1419
1420 return vm_page_size();
1421 }
1422
1423 size_t os::page_size_for_region_aligned(size_t region_size, size_t min_pages) {
1424 return page_size_for_region(region_size, min_pages, true);
1425 }
1426
1427 size_t os::page_size_for_region_unaligned(size_t region_size, size_t min_pages) {
1428 return page_size_for_region(region_size, min_pages, false);
1429 }
1430
1431 const char* os::strerror(int e, bool short_text) {
1432 #define ALL_SHARED_ENUMS(X) \
1433 X(E2BIG, "Argument list too long") \
1434 X(EACCES, "Permission denied") \
1435 X(EADDRINUSE, "Address in use") \
1436 X(EADDRNOTAVAIL, "Address not available") \
1437 X(EAFNOSUPPORT, "Address family not supported") \
1438 X(EAGAIN, "Resource unavailable, try again") \
1439 X(EALREADY, "Connection already in progress") \
1440 X(EBADF, "Bad file descriptor") \
1441 X(EBADMSG, "Bad message") \
1442 X(EBUSY, "Device or resource busy") \
1443 X(ECANCELED, "Operation canceled") \
1444 X(ECHILD, "No child processes") \
1445 X(ECONNABORTED, "Connection aborted") \
1446 X(ECONNREFUSED, "Connection refused") \
1447 X(ECONNRESET, "Connection reset") \
1448 X(EDEADLK, "Resource deadlock would occur") \
1449 X(EDESTADDRREQ, "Destination address required") \
1450 X(EDOM, "Mathematics argument out of domain of function") \
1451 X(EEXIST, "File exists") \
1452 X(EFAULT, "Bad address") \
1453 X(EFBIG, "File too large") \
1454 X(EHOSTUNREACH, "Host is unreachable") \
1455 X(EIDRM, "Identifier removed") \
1456 X(EILSEQ, "Illegal byte sequence") \
1457 X(EINPROGRESS, "Operation in progress") \
1458 X(EINTR, "Interrupted function") \
1459 X(EINVAL, "Invalid argument") \
1460 X(EIO, "I/O error") \
1461 X(EISCONN, "Socket is connected") \
1462 X(EISDIR, "Is a directory") \
1463 X(ELOOP, "Too many levels of symbolic links") \
1464 X(EMFILE, "Too many open files") \
1465 X(EMLINK, "Too many links") \
1466 X(EMSGSIZE, "Message too large") \
1467 X(ENAMETOOLONG, "Filename too long") \
1468 X(ENETDOWN, "Network is down") \
1469 X(ENETRESET, "Connection aborted by network") \
1470 X(ENETUNREACH, "Network unreachable") \
1471 X(ENFILE, "Too many files open in system") \
1472 X(ENOBUFS, "No buffer space available") \
1473 X(ENODATA, "No message is available on the STREAM head read queue") \
1474 X(ENODEV, "No such device") \
1475 X(ENOENT, "No such file or directory") \
1476 X(ENOEXEC, "Executable file format error") \
1477 X(ENOLCK, "No locks available") \
1478 X(ENOLINK, "Reserved") \
1479 X(ENOMEM, "Not enough space") \
1480 X(ENOMSG, "No message of the desired type") \
1481 X(ENOPROTOOPT, "Protocol not available") \
1482 X(ENOSPC, "No space left on device") \
1483 X(ENOSR, "No STREAM resources") \
1484 X(ENOSTR, "Not a STREAM") \
1485 X(ENOSYS, "Function not supported") \
1486 X(ENOTCONN, "The socket is not connected") \
1487 X(ENOTDIR, "Not a directory") \
1488 X(ENOTEMPTY, "Directory not empty") \
1489 X(ENOTSOCK, "Not a socket") \
1490 X(ENOTSUP, "Not supported") \
1491 X(ENOTTY, "Inappropriate I/O control operation") \
1492 X(ENXIO, "No such device or address") \
1493 X(EOPNOTSUPP, "Operation not supported on socket") \
1494 X(EOVERFLOW, "Value too large to be stored in data type") \
1495 X(EPERM, "Operation not permitted") \
1496 X(EPIPE, "Broken pipe") \
1497 X(EPROTO, "Protocol error") \
1498 X(EPROTONOSUPPORT, "Protocol not supported") \
1499 X(EPROTOTYPE, "Protocol wrong type for socket") \
1500 X(ERANGE, "Result too large") \
1501 X(EROFS, "Read-only file system") \
1502 X(ESPIPE, "Invalid seek") \
1503 X(ESRCH, "No such process") \
1504 X(ETIME, "Stream ioctl() timeout") \
1505 X(ETIMEDOUT, "Connection timed out") \
1506 X(ETXTBSY, "Text file busy") \
1507 X(EWOULDBLOCK, "Operation would block") \
1508 X(EXDEV, "Cross-device link")
1509
1510 #define DEFINE_ENTRY(e, text) { e, #e, text },
1511
1512 static const struct {
1513 int v;
1514 const char* short_text;
1515 const char* long_text;
1516 } table [] = {
1517
1518 ALL_SHARED_ENUMS(DEFINE_ENTRY)
1519
1520 // The following enums are not defined on all platforms.
1521 #ifdef ESTALE
1522 DEFINE_ENTRY(ESTALE, "Reserved")
1523 #endif
1524 #ifdef EDQUOT
1525 DEFINE_ENTRY(EDQUOT, "Reserved")
1526 #endif
1527 #ifdef EMULTIHOP
1528 DEFINE_ENTRY(EMULTIHOP, "Reserved")
1529 #endif
1530
1531 // End marker.
1532 { -1, NULL, NULL }
1533
1534 };
1535
1536 #undef DEFINE_ENTRY
1537 #undef ALL_FLAGS
1538
1539 int i = 0;
1540 while (table[i].v != -1 && table[i].v != e) {
1541 i ++;
1542 }
1543
1544 if (table[i].v == e) {
1545 return short_text ? table[i].short_text : table[i].long_text;
1546 }
1547
1548 return "unknown";
1549
1550 }
1551
1552 #ifndef PRODUCT
1553 void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count)
1554 {
1555 if (TracePageSizes) {
1556 tty->print("%s: ", str);
1557 for (int i = 0; i < count; ++i) {
1558 tty->print(" " SIZE_FORMAT, page_sizes[i]);
1559 }
1560 tty->cr();
1561 }
1562 }
1563
1564 void os::trace_page_sizes(const char* str, const size_t region_min_size,
1565 const size_t region_max_size, const size_t page_size,
1566 const char* base, const size_t size)
1567 {
1568 if (TracePageSizes) {
1569 tty->print_cr("%s: min=" SIZE_FORMAT " max=" SIZE_FORMAT
1570 " pg_sz=" SIZE_FORMAT " base=" PTR_FORMAT
1571 " size=" SIZE_FORMAT,
1572 str, region_min_size, region_max_size,
1573 page_size, p2i(base), size);
1574 }
1575 }
1576 #endif // #ifndef PRODUCT
1577
1578 // This is the working definition of a server class machine:
1579 // >= 2 physical CPU's and >=2GB of memory, with some fuzz
1580 // because the graphics memory (?) sometimes masks physical memory.
1581 // If you want to change the definition of a server class machine
1582 // on some OS or platform, e.g., >=4GB on Windows platforms,
1583 // then you'll have to parameterize this method based on that state,
1584 // as was done for logical processors here, or replicate and
1585 // specialize this method for each platform. (Or fix os to have
1586 // some inheritance structure and use subclassing. Sigh.)
1587 // If you want some platform to always or never behave as a server
1588 // class machine, change the setting of AlwaysActAsServerClassMachine
1589 // and NeverActAsServerClassMachine in globals*.hpp.
1590 bool os::is_server_class_machine() {
1591 // First check for the early returns
1592 if (NeverActAsServerClassMachine) {
1593 return false;
1594 }
1595 if (AlwaysActAsServerClassMachine) {
1596 return true;
1597 }
1598 // Then actually look at the machine
1599 bool result = false;
1600 const unsigned int server_processors = 2;
1601 const julong server_memory = 2UL * G;
1602 // We seem not to get our full complement of memory.
1603 // We allow some part (1/8?) of the memory to be "missing",
1604 // based on the sizes of DIMMs, and maybe graphics cards.
1605 const julong missing_memory = 256UL * M;
1606
1607 /* Is this a server class machine? */
1608 if ((os::active_processor_count() >= (int)server_processors) &&
1609 (os::physical_memory() >= (server_memory - missing_memory))) {
1610 const unsigned int logical_processors =
1611 VM_Version::logical_processors_per_package();
1612 if (logical_processors > 1) {
1613 const unsigned int physical_packages =
1614 os::active_processor_count() / logical_processors;
1615 if (physical_packages >= server_processors) {
1616 result = true;
1617 }
1618 } else {
1619 result = true;
1620 }
1621 }
1622 return result;
1623 }
1624
1625 void os::SuspendedThreadTask::run() {
1626 assert(Threads_lock->owned_by_self() || (_thread == VMThread::vm_thread()), "must have threads lock to call this");
1627 internal_do_task();
1628 _done = true;
1629 }
1630
1631 bool os::create_stack_guard_pages(char* addr, size_t bytes) {
1632 return os::pd_create_stack_guard_pages(addr, bytes);
1633 }
1634
1635 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint) {
1636 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1637 if (result != NULL) {
1638 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1639 }
1640
1641 return result;
1642 }
1643
1644 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint,
1645 MEMFLAGS flags) {
1646 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1647 if (result != NULL) {
1648 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1649 MemTracker::record_virtual_memory_type((address)result, flags);
1650 }
1651
1652 return result;
1653 }
1654
1655 char* os::attempt_reserve_memory_at(size_t bytes, char* addr) {
1656 char* result = pd_attempt_reserve_memory_at(bytes, addr);
1657 if (result != NULL) {
1658 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1659 }
1660 return result;
1661 }
1662
1663 void os::split_reserved_memory(char *base, size_t size,
1664 size_t split, bool realloc) {
1665 pd_split_reserved_memory(base, size, split, realloc);
1666 }
1667
1668 bool os::commit_memory(char* addr, size_t bytes, bool executable) {
1669 bool res = pd_commit_memory(addr, bytes, executable);
1670 if (res) {
1671 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1672 }
1673 return res;
1674 }
1675
1676 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint,
1677 bool executable) {
1678 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable);
1679 if (res) {
1680 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1681 }
1682 return res;
1683 }
1684
1685 void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable,
1686 const char* mesg) {
1687 pd_commit_memory_or_exit(addr, bytes, executable, mesg);
1688 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1689 }
1690
1691 void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint,
1692 bool executable, const char* mesg) {
1693 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg);
1694 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1695 }
1696
1697 bool os::uncommit_memory(char* addr, size_t bytes) {
1698 bool res;
1699 if (MemTracker::tracking_level() > NMT_minimal) {
1700 Tracker tkr = MemTracker::get_virtual_memory_uncommit_tracker();
1701 res = pd_uncommit_memory(addr, bytes);
1702 if (res) {
1703 tkr.record((address)addr, bytes);
1704 }
1705 } else {
1706 res = pd_uncommit_memory(addr, bytes);
1707 }
1708 return res;
1709 }
1710
1711 bool os::release_memory(char* addr, size_t bytes) {
1712 bool res;
1713 if (MemTracker::tracking_level() > NMT_minimal) {
1714 Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
1715 res = pd_release_memory(addr, bytes);
1716 if (res) {
1717 tkr.record((address)addr, bytes);
1718 }
1719 } else {
1720 res = pd_release_memory(addr, bytes);
1721 }
1722 return res;
1723 }
1724
1725 void os::pretouch_memory(char* start, char* end) {
1726 for (volatile char *p = start; p < end; p += os::vm_page_size()) {
1727 *p = 0;
1728 }
1729 }
1730
1731 char* os::map_memory(int fd, const char* file_name, size_t file_offset,
1732 char *addr, size_t bytes, bool read_only,
1733 bool allow_exec) {
1734 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec);
1735 if (result != NULL) {
1736 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC);
1737 }
1738 return result;
1739 }
1740
1741 char* os::remap_memory(int fd, const char* file_name, size_t file_offset,
1742 char *addr, size_t bytes, bool read_only,
1743 bool allow_exec) {
1744 return pd_remap_memory(fd, file_name, file_offset, addr, bytes,
1745 read_only, allow_exec);
1746 }
1747
1748 bool os::unmap_memory(char *addr, size_t bytes) {
1749 bool result;
1750 if (MemTracker::tracking_level() > NMT_minimal) {
1751 Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
1752 result = pd_unmap_memory(addr, bytes);
1753 if (result) {
1754 tkr.record((address)addr, bytes);
1755 }
1756 } else {
1757 result = pd_unmap_memory(addr, bytes);
1758 }
1759 return result;
1760 }
1761
1762 void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) {
1763 pd_free_memory(addr, bytes, alignment_hint);
1764 }
1765
1766 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
1767 pd_realign_memory(addr, bytes, alignment_hint);
1768 }
1769
1770 #ifndef TARGET_OS_FAMILY_windows
1771 /* try to switch state from state "from" to state "to"
1772 * returns the state set after the method is complete
1773 */
1774 os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from,
1775 os::SuspendResume::State to)
1776 {
1777 os::SuspendResume::State result =
1778 (os::SuspendResume::State) Atomic::cmpxchg((jint) to, (jint *) &_state, (jint) from);
1779 if (result == from) {
1780 // success
1781 return to;
1782 }
1783 return result;
1784 }
1785 #endif
1786
1787 /////////////// Unit tests ///////////////
1788
1789 #ifndef PRODUCT
1790
1791 #define assert_eq(a,b) assert(a == b, SIZE_FORMAT " != " SIZE_FORMAT, a, b)
1792
1793 class TestOS : AllStatic {
1794 static size_t small_page_size() {
1795 return os::vm_page_size();
1796 }
1797
1798 static size_t large_page_size() {
1799 const size_t large_page_size_example = 4 * M;
1800 return os::page_size_for_region_aligned(large_page_size_example, 1);
1801 }
1802
1803 static void test_page_size_for_region_aligned() {
1804 if (UseLargePages) {
1805 const size_t small_page = small_page_size();
1806 const size_t large_page = large_page_size();
1807
1808 if (large_page > small_page) {
1809 size_t num_small_pages_in_large = large_page / small_page;
1810 size_t page = os::page_size_for_region_aligned(large_page, num_small_pages_in_large);
1811
1812 assert_eq(page, small_page);
1813 }
1814 }
1815 }
1816
1817 static void test_page_size_for_region_alignment() {
1818 if (UseLargePages) {
1819 const size_t small_page = small_page_size();
1820 const size_t large_page = large_page_size();
1821 if (large_page > small_page) {
1822 const size_t unaligned_region = large_page + 17;
1823 size_t page = os::page_size_for_region_aligned(unaligned_region, 1);
1824 assert_eq(page, small_page);
1825
1826 const size_t num_pages = 5;
1827 const size_t aligned_region = large_page * num_pages;
1828 page = os::page_size_for_region_aligned(aligned_region, num_pages);
1829 assert_eq(page, large_page);
1830 }
1831 }
1832 }
1833
1834 static void test_page_size_for_region_unaligned() {
1835 if (UseLargePages) {
1836 // Given exact page size, should return that page size.
1837 for (size_t i = 0; os::_page_sizes[i] != 0; i++) {
1838 size_t expected = os::_page_sizes[i];
1839 size_t actual = os::page_size_for_region_unaligned(expected, 1);
1840 assert_eq(expected, actual);
1841 }
1842
1843 // Given slightly larger size than a page size, return the page size.
1844 for (size_t i = 0; os::_page_sizes[i] != 0; i++) {
1845 size_t expected = os::_page_sizes[i];
1846 size_t actual = os::page_size_for_region_unaligned(expected + 17, 1);
1847 assert_eq(expected, actual);
1848 }
1849
1850 // Given a slightly smaller size than a page size,
1851 // return the next smaller page size.
1852 if (os::_page_sizes[1] > os::_page_sizes[0]) {
1853 size_t expected = os::_page_sizes[0];
1854 size_t actual = os::page_size_for_region_unaligned(os::_page_sizes[1] - 17, 1);
1855 assert_eq(actual, expected);
1856 }
1857
1858 // Return small page size for values less than a small page.
1859 size_t small_page = small_page_size();
1860 size_t actual = os::page_size_for_region_unaligned(small_page - 17, 1);
1861 assert_eq(small_page, actual);
1862 }
1863 }
1864
1865 public:
1866 static void run_tests() {
1867 test_page_size_for_region_aligned();
1868 test_page_size_for_region_alignment();
1869 test_page_size_for_region_unaligned();
1870 }
1871 };
1872
1873 void TestOS_test() {
1874 TestOS::run_tests();
1875 }
1876
1877 #endif // PRODUCT