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 "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_implementation/shared/vmGCOperations.hpp"
34 #include "interpreter/interpreter.hpp"
35 #include "memory/allocation.inline.hpp"
36 #ifdef ASSERT
37 #include "memory/guardedMemory.hpp"
38 #endif
39 #include "oops/oop.inline.hpp"
40 #include "prims/jvm.h"
41 #include "prims/jvm_misc.hpp"
42 #include "prims/privilegedStack.hpp"
43 #include "runtime/arguments.hpp"
44 #include "runtime/atomic.inline.hpp"
45 #include "runtime/frame.inline.hpp"
46 #include "runtime/interfaceSupport.hpp"
47 #include "runtime/java.hpp"
48 #include "runtime/javaCalls.hpp"
49 #include "runtime/mutexLocker.hpp"
50 #include "runtime/os.inline.hpp"
51 #include "runtime/stubRoutines.hpp"
52 #include "runtime/thread.inline.hpp"
53 #include "runtime/vm_version.hpp"
54 #include "services/attachListener.hpp"
55 #include "services/nmtCommon.hpp"
56 #include "services/mallocTracker.hpp"
57 #include "services/memTracker.hpp"
58 #include "services/threadService.hpp"
59 #include "utilities/defaultStream.hpp"
60 #include "utilities/events.hpp"
61
62 # include <signal.h>
63
64 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
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 static const char* iso8601_format =
102 "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d";
103 static const size_t needed_buffer = 29;
104
105 // Sanity check the arguments
106 if (buffer == NULL) {
107 assert(false, "NULL buffer");
108 return NULL;
109 }
110 if (buffer_length < needed_buffer) {
111 assert(false, "buffer_length too small");
112 return NULL;
113 }
114 // Get the current time
115 jlong milliseconds_since_19700101 = javaTimeMillis();
116 const int milliseconds_per_microsecond = 1000;
117 const time_t seconds_since_19700101 =
118 milliseconds_since_19700101 / milliseconds_per_microsecond;
119 const int milliseconds_after_second =
120 milliseconds_since_19700101 % milliseconds_per_microsecond;
121 // Convert the time value to a tm and timezone variable
122 struct tm time_struct;
123 if (localtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
124 assert(false, "Failed localtime_pd");
125 return NULL;
126 }
127 #if defined(_ALLBSD_SOURCE)
128 const time_t zone = (time_t) time_struct.tm_gmtoff;
129 #else
130 const time_t zone = timezone;
131 #endif
132
133 // If daylight savings time is in effect,
134 // we are 1 hour East of our time zone
135 const time_t seconds_per_minute = 60;
136 const time_t minutes_per_hour = 60;
137 const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour;
138 time_t UTC_to_local = zone;
139 if (time_struct.tm_isdst > 0) {
140 UTC_to_local = UTC_to_local - seconds_per_hour;
141 }
142 // Compute the time zone offset.
143 // localtime_pd() sets timezone to the difference (in seconds)
144 // between UTC and and local time.
145 // ISO 8601 says we need the difference between local time and UTC,
146 // we change the sign of the localtime_pd() result.
147 const time_t local_to_UTC = -(UTC_to_local);
148 // Then we have to figure out if if we are ahead (+) or behind (-) UTC.
149 char sign_local_to_UTC = '+';
150 time_t abs_local_to_UTC = local_to_UTC;
151 if (local_to_UTC < 0) {
152 sign_local_to_UTC = '-';
153 abs_local_to_UTC = -(abs_local_to_UTC);
154 }
155 // Convert time zone offset seconds to hours and minutes.
156 const time_t zone_hours = (abs_local_to_UTC / seconds_per_hour);
157 const time_t zone_min =
158 ((abs_local_to_UTC % seconds_per_hour) / seconds_per_minute);
159
160 // Print an ISO 8601 date and time stamp into the buffer
161 const int year = 1900 + time_struct.tm_year;
162 const int month = 1 + time_struct.tm_mon;
163 const int printed = jio_snprintf(buffer, buffer_length, iso8601_format,
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(gclog_or_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::sun_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
321 void os::signal_init() {
322 if (!ReduceSignalUsage) {
323 // Setup JavaThread for processing signals
324 EXCEPTION_MARK;
325 Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(), true, CHECK);
326 instanceKlassHandle klass (THREAD, k);
327 instanceHandle thread_oop = klass->allocate_instance_handle(CHECK);
328
329 const char thread_name[] = "Signal Dispatcher";
330 Handle string = java_lang_String::create_from_str(thread_name, CHECK);
331
332 // Initialize thread_oop to put it into the system threadGroup
333 Handle thread_group (THREAD, Universe::system_thread_group());
334 JavaValue result(T_VOID);
335 JavaCalls::call_special(&result, thread_oop,
336 klass,
337 vmSymbols::object_initializer_name(),
338 vmSymbols::threadgroup_string_void_signature(),
339 thread_group,
340 string,
341 CHECK);
342
343 KlassHandle group(THREAD, SystemDictionary::ThreadGroup_klass());
344 JavaCalls::call_special(&result,
345 thread_group,
346 group,
347 vmSymbols::add_method_name(),
348 vmSymbols::thread_void_signature(),
349 thread_oop, // ARG 1
350 CHECK);
351
352 os::signal_init_pd();
353
354 { MutexLocker mu(Threads_lock);
355 JavaThread* signal_thread = new JavaThread(&signal_thread_entry);
356
357 // At this point it may be possible that no osthread was created for the
358 // JavaThread due to lack of memory. We would have to throw an exception
359 // in that case. However, since this must work and we do not allow
360 // exceptions anyway, check and abort if this fails.
361 if (signal_thread == NULL || signal_thread->osthread() == NULL) {
362 vm_exit_during_initialization("java.lang.OutOfMemoryError",
363 os::native_thread_creation_failed_msg());
364 }
365
366 java_lang_Thread::set_thread(thread_oop(), signal_thread);
367 java_lang_Thread::set_priority(thread_oop(), NearMaxPriority);
368 java_lang_Thread::set_daemon(thread_oop());
369
370 signal_thread->set_threadObj(thread_oop());
371 Threads::add(signal_thread);
372 Thread::start(signal_thread);
373 }
374 // Handle ^BREAK
375 os::signal(SIGBREAK, os::user_handler());
376 }
377 }
378
379
380 void os::terminate_signal_thread() {
381 if (!ReduceSignalUsage)
382 signal_notify(sigexitnum_pd());
383 }
384
385
386 // --------------------- loading libraries ---------------------
387
388 typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *);
389 extern struct JavaVM_ main_vm;
390
391 static void* _native_java_library = NULL;
392
393 void* os::native_java_library() {
394 if (_native_java_library == NULL) {
395 char buffer[JVM_MAXPATHLEN];
396 char ebuf[1024];
397
398 // Try to load verify dll first. In 1.3 java dll depends on it and is not
399 // always able to find it when the loading executable is outside the JDK.
400 // In order to keep working with 1.2 we ignore any loading errors.
401 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
402 "verify")) {
403 dll_load(buffer, ebuf, sizeof(ebuf));
404 }
405
406 // Load java dll
407 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
408 "java")) {
409 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf));
410 }
411 if (_native_java_library == NULL) {
412 vm_exit_during_initialization("Unable to load native library", ebuf);
413 }
414
415 #if defined(__OpenBSD__)
416 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so
417 // ignore errors
418 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
419 "net")) {
420 dll_load(buffer, ebuf, sizeof(ebuf));
421 }
422 #endif
423 }
424 static jboolean onLoaded = JNI_FALSE;
425 if (onLoaded) {
426 // We may have to wait to fire OnLoad until TLS is initialized.
427 if (ThreadLocalStorage::is_initialized()) {
428 // The JNI_OnLoad handling is normally done by method load in
429 // java.lang.ClassLoader$NativeLibrary, but the VM loads the base library
430 // explicitly so we have to check for JNI_OnLoad as well
431 const char *onLoadSymbols[] = JNI_ONLOAD_SYMBOLS;
432 JNI_OnLoad_t JNI_OnLoad = CAST_TO_FN_PTR(
433 JNI_OnLoad_t, dll_lookup(_native_java_library, onLoadSymbols[0]));
434 if (JNI_OnLoad != NULL) {
435 JavaThread* thread = JavaThread::current();
436 ThreadToNativeFromVM ttn(thread);
437 HandleMark hm(thread);
438 jint ver = (*JNI_OnLoad)(&main_vm, NULL);
439 onLoaded = JNI_TRUE;
440 if (!Threads::is_supported_jni_version_including_1_1(ver)) {
441 vm_exit_during_initialization("Unsupported JNI version");
442 }
443 }
444 }
445 }
446 return _native_java_library;
447 }
448
449 /*
450 * Support for finding Agent_On(Un)Load/Attach<_lib_name> if it exists.
451 * If check_lib == true then we are looking for an
452 * Agent_OnLoad_lib_name or Agent_OnAttach_lib_name function to determine if
453 * this library is statically linked into the image.
454 * If check_lib == false then we will look for the appropriate symbol in the
455 * executable if agent_lib->is_static_lib() == true or in the shared library
456 * referenced by 'handle'.
457 */
458 void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib,
459 const char *syms[], size_t syms_len) {
460 assert(agent_lib != NULL, "sanity check");
461 const char *lib_name;
462 void *handle = agent_lib->os_lib();
463 void *entryName = NULL;
464 char *agent_function_name;
465 size_t i;
466
467 // If checking then use the agent name otherwise test is_static_lib() to
468 // see how to process this lookup
469 lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL);
470 for (i = 0; i < syms_len; i++) {
471 agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path());
472 if (agent_function_name == NULL) {
473 break;
474 }
475 entryName = dll_lookup(handle, agent_function_name);
476 FREE_C_HEAP_ARRAY(char, agent_function_name, mtThread);
477 if (entryName != NULL) {
478 break;
479 }
480 }
481 return entryName;
482 }
483
484 // See if the passed in agent is statically linked into the VM image.
485 bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
486 size_t syms_len) {
487 void *ret;
488 void *proc_handle;
489 void *save_handle;
490
491 assert(agent_lib != NULL, "sanity check");
492 if (agent_lib->name() == NULL) {
493 return false;
494 }
495 proc_handle = get_default_process_handle();
496 // Check for Agent_OnLoad/Attach_lib_name function
497 save_handle = agent_lib->os_lib();
498 // We want to look in this process' symbol table.
499 agent_lib->set_os_lib(proc_handle);
500 ret = find_agent_function(agent_lib, true, syms, syms_len);
501 if (ret != NULL) {
502 // Found an entry point like Agent_OnLoad_lib_name so we have a static agent
503 agent_lib->set_valid();
504 agent_lib->set_static_lib(true);
505 return true;
506 }
507 agent_lib->set_os_lib(save_handle);
508 return false;
509 }
510
511 // --------------------- heap allocation utilities ---------------------
512
513 char *os::strdup(const char *str, MEMFLAGS flags) {
514 size_t size = strlen(str);
515 char *dup_str = (char *)malloc(size + 1, flags);
516 if (dup_str == NULL) return NULL;
517 strcpy(dup_str, str);
518 return dup_str;
519 }
520
521 char* os::strdup_check_oom(const char* str, MEMFLAGS flags) {
522 char* p = os::strdup(str, flags);
523 if (p == NULL) {
524 vm_exit_out_of_memory(strlen(str) + 1, OOM_MALLOC_ERROR, "os::strdup_check_oom");
525 }
526 return p;
527 }
528
529
530 #define paranoid 0 /* only set to 1 if you suspect checking code has bug */
531
532 #ifdef ASSERT
533
534 static void verify_memory(void* ptr) {
535 GuardedMemory guarded(ptr);
536 if (!guarded.verify_guards()) {
537 tty->print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees);
538 tty->print_cr("## memory stomp:");
539 guarded.print_on(tty);
540 fatal("memory stomping error");
541 }
542 }
543
544 #endif
545
546 //
547 // This function supports testing of the malloc out of memory
548 // condition without really running the system out of memory.
549 //
550 static u_char* testMalloc(size_t alloc_size) {
551 assert(MallocMaxTestWords > 0, "sanity check");
552
553 if ((cur_malloc_words + (alloc_size / BytesPerWord)) > MallocMaxTestWords) {
554 return NULL;
555 }
556
557 u_char* ptr = (u_char*)::malloc(alloc_size);
558
559 if (ptr != NULL) {
560 Atomic::add(((jint) (alloc_size / BytesPerWord)),
561 (volatile jint *) &cur_malloc_words);
562 }
563 return ptr;
564 }
565
566 void* os::malloc(size_t size, MEMFLAGS flags) {
567 return os::malloc(size, flags, CALLER_PC);
568 }
569
570 void* os::malloc(size_t size, MEMFLAGS memflags, const NativeCallStack& stack) {
571 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
572 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
573
574 #if INCLUDE_NMT
575 // NMT can not track malloc allocation size > MAX_MALLOC_SIZE, which is
576 // (1GB - 1) on 32-bit system. It is not an issue on 64-bit system, where
577 // MAX_MALLOC_SIZE = ((1 << 62) - 1).
578 // VM code does not have such large malloc allocation. However, it can come
579 // Unsafe call.
580 if (MemTracker::tracking_level() >= NMT_summary && size > MAX_MALLOC_SIZE) {
581 return NULL;
582 }
583 #endif
584
585 #ifdef ASSERT
586 // checking for the WatcherThread and crash_protection first
587 // since os::malloc can be called when the libjvm.{dll,so} is
588 // first loaded and we don't have a thread yet.
589 // try to find the thread after we see that the watcher thread
590 // exists and has crash protection.
591 WatcherThread *wt = WatcherThread::watcher_thread();
592 if (wt != NULL && wt->has_crash_protection()) {
593 Thread* thread = ThreadLocalStorage::get_thread_slow();
594 if (thread == wt) {
595 assert(!wt->has_crash_protection(),
596 "Can't malloc with crash protection from WatcherThread");
597 }
598 }
599 #endif
600
601 if (size == 0) {
602 // return a valid pointer if size is zero
603 // if NULL is returned the calling functions assume out of memory.
604 size = 1;
605 }
606
607 // NMT support
608 NMT_TrackingLevel level = MemTracker::tracking_level();
609 size_t nmt_header_size = MemTracker::malloc_header_size(level);
610
611 #ifndef ASSERT
612 const size_t alloc_size = size + nmt_header_size;
613 #else
614 const size_t alloc_size = GuardedMemory::get_total_size(size + nmt_header_size);
615 if (size + nmt_header_size > alloc_size) { // Check for rollover.
616 return NULL;
617 }
618 #endif
619
620 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
621
622 u_char* ptr;
623 if (MallocMaxTestWords > 0) {
624 ptr = testMalloc(alloc_size);
625 } else {
626 ptr = (u_char*)::malloc(alloc_size);
627 }
628
629 #ifdef ASSERT
630 if (ptr == NULL) {
631 return NULL;
632 }
633 // Wrap memory with guard
634 GuardedMemory guarded(ptr, size + nmt_header_size);
635 ptr = guarded.get_user_ptr();
636 #endif
637 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) {
638 tty->print_cr("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr);
639 breakpoint();
640 }
641 debug_only(if (paranoid) verify_memory(ptr));
642 if (PrintMalloc && tty != NULL) {
643 tty->print_cr("os::malloc " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr);
644 }
645
646 // we do not track guard memory
647 return MemTracker::record_malloc((address)ptr, size, memflags, stack, level);
648 }
649
650 void* os::realloc(void *memblock, size_t size, MEMFLAGS flags) {
651 return os::realloc(memblock, size, flags, CALLER_PC);
652 }
653
654 void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, const NativeCallStack& stack) {
655 #if INCLUDE_NMT
656 // See comments in os::malloc() above
657 if (MemTracker::tracking_level() >= NMT_summary && size > MAX_MALLOC_SIZE) {
658 return NULL;
659 }
660 #endif
661
662 #ifndef ASSERT
663 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
664 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
665 // NMT support
666 void* membase = MemTracker::record_free(memblock);
667 NMT_TrackingLevel level = MemTracker::tracking_level();
668 size_t nmt_header_size = MemTracker::malloc_header_size(level);
669 void* ptr = ::realloc(membase, size + nmt_header_size);
670 return MemTracker::record_malloc(ptr, size, memflags, stack, level);
671 #else
672 if (memblock == NULL) {
673 return os::malloc(size, memflags, stack);
674 }
675 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
676 tty->print_cr("os::realloc caught " PTR_FORMAT, memblock);
677 breakpoint();
678 }
679 // NMT support
680 void* membase = MemTracker::malloc_base(memblock);
681 verify_memory(membase);
682 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
683 if (size == 0) {
684 return NULL;
685 }
686 // always move the block
687 void* ptr = os::malloc(size, memflags, stack);
688 if (PrintMalloc) {
689 tty->print_cr("os::remalloc " SIZE_FORMAT " bytes, " PTR_FORMAT " --> " PTR_FORMAT, size, memblock, ptr);
690 }
691 // Copy to new memory if malloc didn't fail
692 if ( ptr != NULL ) {
693 GuardedMemory guarded(MemTracker::malloc_base(memblock));
694 // Guard's user data contains NMT header
695 size_t memblock_size = guarded.get_user_size() - MemTracker::malloc_header_size(memblock);
696 memcpy(ptr, memblock, MIN2(size, memblock_size));
697 if (paranoid) verify_memory(MemTracker::malloc_base(ptr));
698 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) {
699 tty->print_cr("os::realloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr);
700 breakpoint();
701 }
702 os::free(memblock);
703 }
704 return ptr;
705 #endif
706 }
707
708
709 void os::free(void *memblock, MEMFLAGS memflags) {
710 NOT_PRODUCT(inc_stat_counter(&num_frees, 1));
711 #ifdef ASSERT
712 if (memblock == NULL) return;
713 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
714 if (tty != NULL) tty->print_cr("os::free caught " PTR_FORMAT, memblock);
715 breakpoint();
716 }
717 void* membase = MemTracker::record_free(memblock);
718 verify_memory(membase);
719 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
720
721 GuardedMemory guarded(membase);
722 size_t size = guarded.get_user_size();
723 inc_stat_counter(&free_bytes, size);
724 membase = guarded.release_for_freeing();
725 if (PrintMalloc && tty != NULL) {
726 fprintf(stderr, "os::free " SIZE_FORMAT " bytes --> " PTR_FORMAT "\n", size, (uintptr_t)membase);
727 }
728 ::free(membase);
729 #else
730 void* membase = MemTracker::record_free(memblock);
731 ::free(membase);
732 #endif
733 }
734
735 void os::init_random(long initval) {
736 _rand_seed = initval;
737 }
738
739
740 long os::random() {
741 /* standard, well-known linear congruential random generator with
742 * next_rand = (16807*seed) mod (2**31-1)
743 * see
744 * (1) "Random Number Generators: Good Ones Are Hard to Find",
745 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988),
746 * (2) "Two Fast Implementations of the 'Minimal Standard' Random
747 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88.
748 */
749 const long a = 16807;
750 const unsigned long m = 2147483647;
751 const long q = m / a; assert(q == 127773, "weird math");
752 const long r = m % a; assert(r == 2836, "weird math");
753
754 // compute az=2^31p+q
755 unsigned long lo = a * (long)(_rand_seed & 0xFFFF);
756 unsigned long hi = a * (long)((unsigned long)_rand_seed >> 16);
757 lo += (hi & 0x7FFF) << 16;
758
759 // if q overflowed, ignore the overflow and increment q
760 if (lo > m) {
761 lo &= m;
762 ++lo;
763 }
764 lo += hi >> 15;
765
766 // if (p+q) overflowed, ignore the overflow and increment (p+q)
767 if (lo > m) {
768 lo &= m;
769 ++lo;
770 }
771 return (_rand_seed = lo);
772 }
773
774 // The INITIALIZED state is distinguished from the SUSPENDED state because the
775 // conditions in which a thread is first started are different from those in which
776 // a suspension is resumed. These differences make it hard for us to apply the
777 // tougher checks when starting threads that we want to do when resuming them.
778 // However, when start_thread is called as a result of Thread.start, on a Java
779 // thread, the operation is synchronized on the Java Thread object. So there
780 // cannot be a race to start the thread and hence for the thread to exit while
781 // we are working on it. Non-Java threads that start Java threads either have
782 // to do so in a context in which races are impossible, or should do appropriate
783 // locking.
784
785 void os::start_thread(Thread* thread) {
786 // guard suspend/resume
787 MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag);
788 OSThread* osthread = thread->osthread();
789 osthread->set_state(RUNNABLE);
790 pd_start_thread(thread);
791 }
792
793 //---------------------------------------------------------------------------
794 // Helper functions for fatal error handler
795
796 void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) {
797 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking");
798
799 int cols = 0;
800 int cols_per_line = 0;
801 switch (unitsize) {
802 case 1: cols_per_line = 16; break;
803 case 2: cols_per_line = 8; break;
804 case 4: cols_per_line = 4; break;
805 case 8: cols_per_line = 2; break;
806 default: return;
807 }
808
809 address p = start;
810 st->print(PTR_FORMAT ": ", start);
811 while (p < end) {
812 switch (unitsize) {
813 case 1: st->print("%02x", *(u1*)p); break;
814 case 2: st->print("%04x", *(u2*)p); break;
815 case 4: st->print("%08x", *(u4*)p); break;
816 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break;
817 }
818 p += unitsize;
819 cols++;
820 if (cols >= cols_per_line && p < end) {
821 cols = 0;
822 st->cr();
823 st->print(PTR_FORMAT ": ", p);
824 } else {
825 st->print(" ");
826 }
827 }
828 st->cr();
829 }
830
831 void os::print_environment_variables(outputStream* st, const char** env_list,
832 char* buffer, int len) {
833 if (env_list) {
834 st->print_cr("Environment Variables:");
835
836 for (int i = 0; env_list[i] != NULL; i++) {
837 if (getenv(env_list[i], buffer, len)) {
838 st->print("%s", env_list[i]);
839 st->print("=");
840 st->print_cr("%s", buffer);
841 }
842 }
843 }
844 }
845
846 void os::print_cpu_info(outputStream* st) {
847 // cpu
848 st->print("CPU:");
849 st->print("total %d", os::processor_count());
850 // It's not safe to query number of active processors after crash
851 // st->print("(active %d)", os::active_processor_count());
852 st->print(" %s", VM_Version::cpu_features());
853 st->cr();
854 pd_print_cpu_info(st);
855 }
856
857 void os::print_date_and_time(outputStream *st) {
858 const int secs_per_day = 86400;
859 const int secs_per_hour = 3600;
860 const int secs_per_min = 60;
861
862 time_t tloc;
863 (void)time(&tloc);
864 st->print("time: %s", ctime(&tloc)); // ctime adds newline.
865
866 double t = os::elapsedTime();
867 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in
868 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int
869 // before printf. We lost some precision, but who cares?
870 int eltime = (int)t; // elapsed time in seconds
871
872 // print elapsed time in a human-readable format:
873 int eldays = eltime / secs_per_day;
874 int day_secs = eldays * secs_per_day;
875 int elhours = (eltime - day_secs) / secs_per_hour;
876 int hour_secs = elhours * secs_per_hour;
877 int elmins = (eltime - day_secs - hour_secs) / secs_per_min;
878 int minute_secs = elmins * secs_per_min;
879 int elsecs = (eltime - day_secs - hour_secs - minute_secs);
880 st->print_cr("elapsed time: %d seconds (%dd %dh %dm %ds)", eltime, eldays, elhours, elmins, elsecs);
881 }
882
883 // moved from debug.cpp (used to be find()) but still called from there
884 // The verbose parameter is only set by the debug code in one case
885 void os::print_location(outputStream* st, intptr_t x, bool verbose) {
886 address addr = (address)x;
887 CodeBlob* b = CodeCache::find_blob_unsafe(addr);
888 if (b != NULL) {
889 if (b->is_buffer_blob()) {
890 // the interpreter is generated into a buffer blob
891 InterpreterCodelet* i = Interpreter::codelet_containing(addr);
892 if (i != NULL) {
893 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an Interpreter codelet", addr, (int)(addr - i->code_begin()));
894 i->print_on(st);
895 return;
896 }
897 if (Interpreter::contains(addr)) {
898 st->print_cr(INTPTR_FORMAT " is pointing into interpreter code"
899 " (not bytecode specific)", addr);
900 return;
901 }
902 //
903 if (AdapterHandlerLibrary::contains(b)) {
904 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an AdapterHandler", addr, (int)(addr - b->code_begin()));
905 AdapterHandlerLibrary::print_handler_on(st, b);
906 }
907 // the stubroutines are generated into a buffer blob
908 StubCodeDesc* d = StubCodeDesc::desc_for(addr);
909 if (d != NULL) {
910 st->print_cr(INTPTR_FORMAT " is at begin+%d in a stub", addr, (int)(addr - d->begin()));
911 d->print_on(st);
912 st->cr();
913 return;
914 }
915 if (StubRoutines::contains(addr)) {
916 st->print_cr(INTPTR_FORMAT " is pointing to an (unnamed) "
917 "stub routine", addr);
918 return;
919 }
920 // the InlineCacheBuffer is using stubs generated into a buffer blob
921 if (InlineCacheBuffer::contains(addr)) {
922 st->print_cr(INTPTR_FORMAT " is pointing into InlineCacheBuffer", addr);
923 return;
924 }
925 VtableStub* v = VtableStubs::stub_containing(addr);
926 if (v != NULL) {
927 st->print_cr(INTPTR_FORMAT " is at entry_point+%d in a vtable stub", addr, (int)(addr - v->entry_point()));
928 v->print_on(st);
929 st->cr();
930 return;
931 }
932 }
933 nmethod* nm = b->as_nmethod_or_null();
934 if (nm != NULL) {
935 ResourceMark rm;
936 st->print(INTPTR_FORMAT " is at entry_point+%d in (nmethod*)" INTPTR_FORMAT,
937 addr, (int)(addr - nm->entry_point()), nm);
938 if (verbose) {
939 st->print(" for ");
940 nm->method()->print_value_on(st);
941 }
942 st->cr();
943 nm->print_nmethod(verbose);
944 return;
945 }
946 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in ", addr, (int)(addr - b->code_begin()));
947 b->print_on(st);
948 return;
949 }
950
951 if (Universe::heap()->is_in(addr)) {
952 HeapWord* p = Universe::heap()->block_start(addr);
953 bool print = false;
954 // If we couldn't find it it just may mean that heap wasn't parsable
955 // See if we were just given an oop directly
956 if (p != NULL && Universe::heap()->block_is_obj(p)) {
957 print = true;
958 } else if (p == NULL && ((oopDesc*)addr)->is_oop()) {
959 p = (HeapWord*) addr;
960 print = true;
961 }
962 if (print) {
963 if (p == (HeapWord*) addr) {
964 st->print_cr(INTPTR_FORMAT " is an oop", addr);
965 } else {
966 st->print_cr(INTPTR_FORMAT " is pointing into object: " INTPTR_FORMAT, addr, p);
967 }
968 oop(p)->print_on(st);
969 return;
970 }
971 } else {
972 if (Universe::heap()->is_in_reserved(addr)) {
973 st->print_cr(INTPTR_FORMAT " is an unallocated location "
974 "in the heap", addr);
975 return;
976 }
977 }
978 if (JNIHandles::is_global_handle((jobject) addr)) {
979 st->print_cr(INTPTR_FORMAT " is a global jni handle", addr);
980 return;
981 }
982 if (JNIHandles::is_weak_global_handle((jobject) addr)) {
983 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", addr);
984 return;
985 }
986 #ifndef PRODUCT
987 // we don't keep the block list in product mode
988 if (JNIHandleBlock::any_contains((jobject) addr)) {
989 st->print_cr(INTPTR_FORMAT " is a local jni handle", addr);
990 return;
991 }
992 #endif
993
994 for(JavaThread *thread = Threads::first(); thread; thread = thread->next()) {
995 // Check for privilege stack
996 if (thread->privileged_stack_top() != NULL &&
997 thread->privileged_stack_top()->contains(addr)) {
998 st->print_cr(INTPTR_FORMAT " is pointing into the privilege stack "
999 "for thread: " INTPTR_FORMAT, addr, thread);
1000 if (verbose) thread->print_on(st);
1001 return;
1002 }
1003 // If the addr is a java thread print information about that.
1004 if (addr == (address)thread) {
1005 if (verbose) {
1006 thread->print_on(st);
1007 } else {
1008 st->print_cr(INTPTR_FORMAT " is a thread", addr);
1009 }
1010 return;
1011 }
1012 // If the addr is in the stack region for this thread then report that
1013 // and print thread info
1014 if (thread->stack_base() >= addr &&
1015 addr > (thread->stack_base() - thread->stack_size())) {
1016 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: "
1017 INTPTR_FORMAT, addr, thread);
1018 if (verbose) thread->print_on(st);
1019 return;
1020 }
1021
1022 }
1023
1024 // Check if in metaspace and print types that have vptrs (only method now)
1025 if (Metaspace::contains(addr)) {
1026 if (Method::has_method_vptr((const void*)addr)) {
1027 ((Method*)addr)->print_value_on(st);
1028 st->cr();
1029 } else {
1030 // Use addr->print() from the debugger instead (not here)
1031 st->print_cr(INTPTR_FORMAT " is pointing into metadata", addr);
1032 }
1033 return;
1034 }
1035
1036 // Try an OS specific find
1037 if (os::find(addr, st)) {
1038 return;
1039 }
1040
1041 st->print_cr(INTPTR_FORMAT " is an unknown value", addr);
1042 }
1043
1044 // Looks like all platforms except IA64 can use the same function to check
1045 // if C stack is walkable beyond current frame. The check for fp() is not
1046 // necessary on Sparc, but it's harmless.
1047 bool os::is_first_C_frame(frame* fr) {
1048 #if (defined(IA64) && !defined(AIX)) && !defined(_WIN32)
1049 // On IA64 we have to check if the callers bsp is still valid
1050 // (i.e. within the register stack bounds).
1051 // Notice: this only works for threads created by the VM and only if
1052 // we walk the current stack!!! If we want to be able to walk
1053 // arbitrary other threads, we'll have to somehow store the thread
1054 // object in the frame.
1055 Thread *thread = Thread::current();
1056 if ((address)fr->fp() <=
1057 thread->register_stack_base() HPUX_ONLY(+ 0x0) LINUX_ONLY(+ 0x50)) {
1058 // This check is a little hacky, because on Linux the first C
1059 // frame's ('start_thread') register stack frame starts at
1060 // "register_stack_base + 0x48" while on HPUX, the first C frame's
1061 // ('__pthread_bound_body') register stack frame seems to really
1062 // start at "register_stack_base".
1063 return true;
1064 } else {
1065 return false;
1066 }
1067 #elif defined(IA64) && defined(_WIN32)
1068 return true;
1069 #else
1070 // Load up sp, fp, sender sp and sender fp, check for reasonable values.
1071 // Check usp first, because if that's bad the other accessors may fault
1072 // on some architectures. Ditto ufp second, etc.
1073 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1);
1074 // sp on amd can be 32 bit aligned.
1075 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1);
1076
1077 uintptr_t usp = (uintptr_t)fr->sp();
1078 if ((usp & sp_align_mask) != 0) return true;
1079
1080 uintptr_t ufp = (uintptr_t)fr->fp();
1081 if ((ufp & fp_align_mask) != 0) return true;
1082
1083 uintptr_t old_sp = (uintptr_t)fr->sender_sp();
1084 if ((old_sp & sp_align_mask) != 0) return true;
1085 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true;
1086
1087 uintptr_t old_fp = (uintptr_t)fr->link();
1088 if ((old_fp & fp_align_mask) != 0) return true;
1089 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true;
1090
1091 // stack grows downwards; if old_fp is below current fp or if the stack
1092 // frame is too large, either the stack is corrupted or fp is not saved
1093 // on stack (i.e. on x86, ebp may be used as general register). The stack
1094 // is not walkable beyond current frame.
1095 if (old_fp < ufp) return true;
1096 if (old_fp - ufp > 64 * K) return true;
1097
1098 return false;
1099 #endif
1100 }
1101
1102 #ifdef ASSERT
1103 extern "C" void test_random() {
1104 const double m = 2147483647;
1105 double mean = 0.0, variance = 0.0, t;
1106 long reps = 10000;
1107 unsigned long seed = 1;
1108
1109 tty->print_cr("seed %ld for %ld repeats...", seed, reps);
1110 os::init_random(seed);
1111 long num;
1112 for (int k = 0; k < reps; k++) {
1113 num = os::random();
1114 double u = (double)num / m;
1115 assert(u >= 0.0 && u <= 1.0, "bad random number!");
1116
1117 // calculate mean and variance of the random sequence
1118 mean += u;
1119 variance += (u*u);
1120 }
1121 mean /= reps;
1122 variance /= (reps - 1);
1123
1124 assert(num == 1043618065, "bad seed");
1125 tty->print_cr("mean of the 1st 10000 numbers: %f", mean);
1126 tty->print_cr("variance of the 1st 10000 numbers: %f", variance);
1127 const double eps = 0.0001;
1128 t = fabsd(mean - 0.5018);
1129 assert(t < eps, "bad mean");
1130 t = (variance - 0.3355) < 0.0 ? -(variance - 0.3355) : variance - 0.3355;
1131 assert(t < eps, "bad variance");
1132 }
1133 #endif
1134
1135
1136 // Set up the boot classpath.
1137
1138 char* os::format_boot_path(const char* format_string,
1139 const char* home,
1140 int home_len,
1141 char fileSep,
1142 char pathSep) {
1143 assert((fileSep == '/' && pathSep == ':') ||
1144 (fileSep == '\\' && pathSep == ';'), "unexpected separator chars");
1145
1146 // Scan the format string to determine the length of the actual
1147 // boot classpath, and handle platform dependencies as well.
1148 int formatted_path_len = 0;
1149 const char* p;
1150 for (p = format_string; *p != 0; ++p) {
1151 if (*p == '%') formatted_path_len += home_len - 1;
1152 ++formatted_path_len;
1153 }
1154
1155 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal);
1156 if (formatted_path == NULL) {
1157 return NULL;
1158 }
1159
1160 // Create boot classpath from format, substituting separator chars and
1161 // java home directory.
1162 char* q = formatted_path;
1163 for (p = format_string; *p != 0; ++p) {
1164 switch (*p) {
1165 case '%':
1166 strcpy(q, home);
1167 q += home_len;
1168 break;
1169 case '/':
1170 *q++ = fileSep;
1171 break;
1172 case ':':
1173 *q++ = pathSep;
1174 break;
1175 default:
1176 *q++ = *p;
1177 }
1178 }
1179 *q = '\0';
1180
1181 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched");
1182 return formatted_path;
1183 }
1184
1185 // returns a PATH of all entries in the given directory that do not start with a '.'
1186 static char* expand_entries_to_path(char* directory, char fileSep, char pathSep) {
1187 DIR* dir = os::opendir(directory);
1188 if (dir == NULL) return NULL;
1189
1190 char* path = NULL;
1191 size_t path_len = 0; // path length including \0 terminator
1192
1193 size_t directory_len = strlen(directory);
1194 struct dirent *entry;
1195 char* dbuf = NEW_C_HEAP_ARRAY(char, os::readdir_buf_size(directory), mtInternal);
1196 while ((entry = os::readdir(dir, (dirent *) dbuf)) != NULL) {
1197 const char* name = entry->d_name;
1198 if (name[0] == '.') continue;
1199
1200 size_t name_len = strlen(name);
1201 size_t needed = directory_len + name_len + 2;
1202 size_t new_len = path_len + needed;
1203 if (path == NULL) {
1204 path = NEW_C_HEAP_ARRAY(char, new_len, mtInternal);
1205 } else {
1206 path = REALLOC_C_HEAP_ARRAY(char, path, new_len, mtInternal);
1207 }
1208 if (path == NULL)
1209 break;
1210
1211 // append <pathSep>directory<fileSep>name
1212 char* p = path;
1213 if (path_len > 0) {
1214 p += (path_len -1);
1215 *p = pathSep;
1216 p++;
1217 }
1218
1219 strcpy(p, directory);
1220 p += directory_len;
1221
1222 *p = fileSep;
1223 p++;
1224
1225 strcpy(p, name);
1226 p += name_len;
1227
1228 path_len = new_len;
1229 }
1230
1231 FREE_C_HEAP_ARRAY(char, dbuf, mtInternal);
1232 os::closedir(dir);
1233
1234 return path;
1235 }
1236
1237 bool os::set_boot_path(char fileSep, char pathSep) {
1238 const char* home = Arguments::get_java_home();
1239 int home_len = (int)strlen(home);
1240
1241 static const char* meta_index_dir_format = "%/lib/";
1242 static const char* meta_index_format = "%/lib/meta-index";
1243 char* meta_index = format_boot_path(meta_index_format, home, home_len, fileSep, pathSep);
1244 if (meta_index == NULL) return false;
1245 char* meta_index_dir = format_boot_path(meta_index_dir_format, home, home_len, fileSep, pathSep);
1246 if (meta_index_dir == NULL) return false;
1247 Arguments::set_meta_index_path(meta_index, meta_index_dir);
1248
1249 char* sysclasspath = NULL;
1250
1251 // images build if rt.jar exists
1252 char* rt_jar = format_boot_path("%/lib/rt.jar", home, home_len, fileSep, pathSep);
1253 if (rt_jar == NULL) return false;
1254 struct stat st;
1255 bool has_rt_jar = (os::stat(rt_jar, &st) == 0);
1256 FREE_C_HEAP_ARRAY(char, rt_jar, mtInternal);
1257
1258 if (has_rt_jar) {
1259 // Any modification to the JAR-file list, for the boot classpath must be
1260 // aligned with install/install/make/common/Pack.gmk. Note: boot class
1261 // path class JARs, are stripped for StackMapTable to reduce download size.
1262 static const char classpath_format[] =
1263 "%/lib/resources.jar:"
1264 "%/lib/rt.jar:"
1265 "%/lib/jsse.jar:"
1266 "%/lib/jce.jar:"
1267 "%/lib/charsets.jar:"
1268 "%/lib/jfr.jar:"
1269 "%/classes";
1270 sysclasspath = format_boot_path(classpath_format, home, home_len, fileSep, pathSep);
1271 } else {
1272 // no rt.jar, check if developer build with exploded modules
1273 char* modules_dir = format_boot_path("%/modules", home, home_len, fileSep, pathSep);
1274 if (os::stat(modules_dir, &st) == 0) {
1275 if ((st.st_mode & S_IFDIR) == S_IFDIR) {
1276 sysclasspath = expand_entries_to_path(modules_dir, fileSep, pathSep);
1277 }
1278 }
1279
1280 // fallback to classes
1281 if (sysclasspath == NULL)
1282 sysclasspath = format_boot_path("%/classes", home, home_len, fileSep, pathSep);
1283 }
1284
1285 if (sysclasspath == NULL) return false;
1286 Arguments::set_sysclasspath(sysclasspath);
1287
1288 return true;
1289 }
1290
1291 /*
1292 * Splits a path, based on its separator, the number of
1293 * elements is returned back in n.
1294 * It is the callers responsibility to:
1295 * a> check the value of n, and n may be 0.
1296 * b> ignore any empty path elements
1297 * c> free up the data.
1298 */
1299 char** os::split_path(const char* path, int* n) {
1300 *n = 0;
1301 if (path == NULL || strlen(path) == 0) {
1302 return NULL;
1303 }
1304 const char psepchar = *os::path_separator();
1305 char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal);
1306 if (inpath == NULL) {
1307 return NULL;
1308 }
1309 strcpy(inpath, path);
1310 int count = 1;
1311 char* p = strchr(inpath, psepchar);
1312 // Get a count of elements to allocate memory
1313 while (p != NULL) {
1314 count++;
1315 p++;
1316 p = strchr(p, psepchar);
1317 }
1318 char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count, mtInternal);
1319 if (opath == NULL) {
1320 return NULL;
1321 }
1322
1323 // do the actual splitting
1324 p = inpath;
1325 for (int i = 0 ; i < count ; i++) {
1326 size_t len = strcspn(p, os::path_separator());
1327 if (len > JVM_MAXPATHLEN) {
1328 return NULL;
1329 }
1330 // allocate the string and add terminator storage
1331 char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
1332 if (s == NULL) {
1333 return NULL;
1334 }
1335 strncpy(s, p, len);
1336 s[len] = '\0';
1337 opath[i] = s;
1338 p += len + 1;
1339 }
1340 FREE_C_HEAP_ARRAY(char, inpath, mtInternal);
1341 *n = count;
1342 return opath;
1343 }
1344
1345 void os::set_memory_serialize_page(address page) {
1346 int count = log2_intptr(sizeof(class JavaThread)) - log2_intptr(64);
1347 _mem_serialize_page = (volatile int32_t *)page;
1348 // We initialize the serialization page shift count here
1349 // We assume a cache line size of 64 bytes
1350 assert(SerializePageShiftCount == count,
1351 "thread size changed, fix SerializePageShiftCount constant");
1352 set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t)));
1353 }
1354
1355 static volatile intptr_t SerializePageLock = 0;
1356
1357 // This method is called from signal handler when SIGSEGV occurs while the current
1358 // thread tries to store to the "read-only" memory serialize page during state
1359 // transition.
1360 void os::block_on_serialize_page_trap() {
1361 if (TraceSafepoint) {
1362 tty->print_cr("Block until the serialize page permission restored");
1363 }
1364 // When VMThread is holding the SerializePageLock during modifying the
1365 // access permission of the memory serialize page, the following call
1366 // will block until the permission of that page is restored to rw.
1367 // Generally, it is unsafe to manipulate locks in signal handlers, but in
1368 // this case, it's OK as the signal is synchronous and we know precisely when
1369 // it can occur.
1370 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page");
1371 Thread::muxRelease(&SerializePageLock);
1372 }
1373
1374 // Serialize all thread state variables
1375 void os::serialize_thread_states() {
1376 // On some platforms such as Solaris & Linux, the time duration of the page
1377 // permission restoration is observed to be much longer than expected due to
1378 // scheduler starvation problem etc. To avoid the long synchronization
1379 // time and expensive page trap spinning, 'SerializePageLock' is used to block
1380 // the mutator thread if such case is encountered. See bug 6546278 for details.
1381 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states");
1382 os::protect_memory((char *)os::get_memory_serialize_page(),
1383 os::vm_page_size(), MEM_PROT_READ);
1384 os::protect_memory((char *)os::get_memory_serialize_page(),
1385 os::vm_page_size(), MEM_PROT_RW);
1386 Thread::muxRelease(&SerializePageLock);
1387 }
1388
1389 // Returns true if the current stack pointer is above the stack shadow
1390 // pages, false otherwise.
1391
1392 bool os::stack_shadow_pages_available(Thread *thread, methodHandle method) {
1393 assert(StackRedPages > 0 && StackYellowPages > 0,"Sanity check");
1394 address sp = current_stack_pointer();
1395 // Check if we have StackShadowPages above the yellow zone. This parameter
1396 // is dependent on the depth of the maximum VM call stack possible from
1397 // the handler for stack overflow. 'instanceof' in the stack overflow
1398 // handler or a println uses at least 8k stack of VM and native code
1399 // respectively.
1400 const int framesize_in_bytes =
1401 Interpreter::size_top_interpreter_activation(method()) * wordSize;
1402 int reserved_area = ((StackShadowPages + StackRedPages + StackYellowPages)
1403 * vm_page_size()) + framesize_in_bytes;
1404 // The very lower end of the stack
1405 address stack_limit = thread->stack_base() - thread->stack_size();
1406 return (sp > (stack_limit + reserved_area));
1407 }
1408
1409 size_t os::page_size_for_region(size_t region_size, size_t min_pages) {
1410 assert(min_pages > 0, "sanity");
1411 if (UseLargePages) {
1412 const size_t max_page_size = region_size / min_pages;
1413
1414 for (size_t i = 0; _page_sizes[i] != 0; ++i) {
1415 const size_t page_size = _page_sizes[i];
1416 if (page_size <= max_page_size && is_size_aligned(region_size, page_size)) {
1417 return page_size;
1418 }
1419 }
1420 }
1421
1422 return vm_page_size();
1423 }
1424
1425 #ifndef PRODUCT
1426 void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count)
1427 {
1428 if (TracePageSizes) {
1429 tty->print("%s: ", str);
1430 for (int i = 0; i < count; ++i) {
1431 tty->print(" " SIZE_FORMAT, page_sizes[i]);
1432 }
1433 tty->cr();
1434 }
1435 }
1436
1437 void os::trace_page_sizes(const char* str, const size_t region_min_size,
1438 const size_t region_max_size, const size_t page_size,
1439 const char* base, const size_t size)
1440 {
1441 if (TracePageSizes) {
1442 tty->print_cr("%s: min=" SIZE_FORMAT " max=" SIZE_FORMAT
1443 " pg_sz=" SIZE_FORMAT " base=" PTR_FORMAT
1444 " size=" SIZE_FORMAT,
1445 str, region_min_size, region_max_size,
1446 page_size, base, size);
1447 }
1448 }
1449 #endif // #ifndef PRODUCT
1450
1451 // This is the working definition of a server class machine:
1452 // >= 2 physical CPU's and >=2GB of memory, with some fuzz
1453 // because the graphics memory (?) sometimes masks physical memory.
1454 // If you want to change the definition of a server class machine
1455 // on some OS or platform, e.g., >=4GB on Windows platforms,
1456 // then you'll have to parameterize this method based on that state,
1457 // as was done for logical processors here, or replicate and
1458 // specialize this method for each platform. (Or fix os to have
1459 // some inheritance structure and use subclassing. Sigh.)
1460 // If you want some platform to always or never behave as a server
1461 // class machine, change the setting of AlwaysActAsServerClassMachine
1462 // and NeverActAsServerClassMachine in globals*.hpp.
1463 bool os::is_server_class_machine() {
1464 // First check for the early returns
1465 if (NeverActAsServerClassMachine) {
1466 return false;
1467 }
1468 if (AlwaysActAsServerClassMachine) {
1469 return true;
1470 }
1471 // Then actually look at the machine
1472 bool result = false;
1473 const unsigned int server_processors = 2;
1474 const julong server_memory = 2UL * G;
1475 // We seem not to get our full complement of memory.
1476 // We allow some part (1/8?) of the memory to be "missing",
1477 // based on the sizes of DIMMs, and maybe graphics cards.
1478 const julong missing_memory = 256UL * M;
1479
1480 /* Is this a server class machine? */
1481 if ((os::active_processor_count() >= (int)server_processors) &&
1482 (os::physical_memory() >= (server_memory - missing_memory))) {
1483 const unsigned int logical_processors =
1484 VM_Version::logical_processors_per_package();
1485 if (logical_processors > 1) {
1486 const unsigned int physical_packages =
1487 os::active_processor_count() / logical_processors;
1488 if (physical_packages > server_processors) {
1489 result = true;
1490 }
1491 } else {
1492 result = true;
1493 }
1494 }
1495 return result;
1496 }
1497
1498 void os::SuspendedThreadTask::run() {
1499 assert(Threads_lock->owned_by_self() || (_thread == VMThread::vm_thread()), "must have threads lock to call this");
1500 internal_do_task();
1501 _done = true;
1502 }
1503
1504 bool os::create_stack_guard_pages(char* addr, size_t bytes) {
1505 return os::pd_create_stack_guard_pages(addr, bytes);
1506 }
1507
1508 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint) {
1509 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1510 if (result != NULL) {
1511 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1512 }
1513
1514 return result;
1515 }
1516
1517 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint,
1518 MEMFLAGS flags) {
1519 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1520 if (result != NULL) {
1521 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1522 MemTracker::record_virtual_memory_type((address)result, flags);
1523 }
1524
1525 return result;
1526 }
1527
1528 char* os::attempt_reserve_memory_at(size_t bytes, char* addr) {
1529 char* result = pd_attempt_reserve_memory_at(bytes, addr);
1530 if (result != NULL) {
1531 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1532 }
1533 return result;
1534 }
1535
1536 // A convenience function which attempts to reserve memory at a number
1537 // of given addresses. An address array is given and first the first,
1538 // then the second is tried and so on.
1539 // Function returns NULL if memory could not be obtained at any of the
1540 // given addresses.
1541 //
1542 // parameters
1543 // bytes - size of block
1544 // addr - array of addresses, NULL terminated
1545 //
1546 char* os::attempt_reserve_memory_at_multiple(size_t bytes, char* addr[]) {
1547 for (int i = 0; addr[i]; i ++) {
1548 char* const attach_point = addr[i];
1549 assert(attach_point >= (char *)HeapBaseMinAddress, "Flag support broken");
1550 char* const addr = os::attempt_reserve_memory_at(bytes, attach_point);
1551 if (addr) {
1552 // Note: depending on platform and OS, it is not guaranteed that
1553 // os::attempt_reserve_memory_at only returns requested addr or nothing :/
1554 if (addr != attach_point) {
1555 os::release_memory(addr, bytes);
1556 } else {
1557 return addr;
1558 }
1559 }
1560 }
1561
1562 return NULL;
1563 }
1564
1565 // A convenience function which attempts to reserve memory
1566 // in a given memory range.
1567 char* os::attempt_reserve_memory_in_range(size_t size, size_t alignment,
1568 char* range_from, char* range_to, int num_attempts) {
1569 // sanity checks
1570 if (range_from == 0) {
1571 range_from = (char*) 1;
1572 }
1573
1574 if (size == 0) {
1575 return NULL;
1576 }
1577
1578 if (range_to <= range_from) {
1579 return NULL;
1580 } else {
1581 size_t d = range_to - range_from;
1582 if (d < size) {
1583 return NULL;
1584 }
1585 }
1586
1587 // The necessary attach point alignment (for mmap or shmat to have a
1588 // chance of attaching).
1589 const size_t os_attach_point_alignment =
1590 AIX_ONLY(SIZE_256M) // Known shm boundary alignment.
1591 NOT_AIX(os::vm_allocation_granularity());
1592
1593 const size_t attach_point_alignment =
1594 alignment > 0 ?
1595 lcm(alignment, os_attach_point_alignment) : os_attach_point_alignment;
1596
1597 // Calc address range within we try to attach (range of possible start addresses).
1598 char* const highest_start = (char *)align_ptr_down(range_to - size, attach_point_alignment);
1599 char* const lowest_start = (char *)align_ptr_up(range_from, attach_point_alignment);
1600 const size_t attach_range = highest_start - lowest_start;
1601
1602 // Default is 20 ...
1603 if (num_attempts <= 0) {
1604 num_attempts = 20;
1605 }
1606
1607 // ... but cap at possible
1608 const uint64_t num_attempts_possible =
1609 (attach_range / attach_point_alignment) + 1; // at least one is possible even for 0 sized attach range
1610
1611 if (num_attempts_possible < (uint64_t)num_attempts) {
1612 num_attempts = num_attempts_possible;
1613 }
1614
1615 const size_t stepsize =
1616 align_size_up(attach_range / num_attempts, attach_point_alignment);
1617
1618 // Build up attach point array.
1619 char** attach_points = (char**) os::malloc((num_attempts + 1) * sizeof(char*), mtInternal);
1620 assert(attach_points, "OOM");
1621
1622 // Fill attach points array.
1623 char* attach_point = highest_start;
1624 int i = 0;
1625 while (i < num_attempts && attach_point >= lowest_start) {
1626 attach_points[i] = attach_point;
1627 i++;
1628 // Handle overflow correctly!
1629 if ((uintptr_t)attach_point > stepsize) {
1630 attach_point -= stepsize;
1631 } else {
1632 attach_point = 0;
1633 }
1634 }
1635
1636 attach_points[i] = NULL;
1637
1638 char* addr = os::attempt_reserve_memory_at_multiple(size, attach_points);
1639
1640 os::free(attach_points);
1641
1642 return addr;
1643 }
1644
1645 void os::split_reserved_memory(char *base, size_t size,
1646 size_t split, bool realloc) {
1647 pd_split_reserved_memory(base, size, split, realloc);
1648 }
1649
1650 bool os::commit_memory(char* addr, size_t bytes, bool executable) {
1651 bool res = pd_commit_memory(addr, bytes, executable);
1652 if (res) {
1653 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1654 }
1655 return res;
1656 }
1657
1658 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint,
1659 bool executable) {
1660 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable);
1661 if (res) {
1662 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1663 }
1664 return res;
1665 }
1666
1667 void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable,
1668 const char* mesg) {
1669 pd_commit_memory_or_exit(addr, bytes, executable, mesg);
1670 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1671 }
1672
1673 void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint,
1674 bool executable, const char* mesg) {
1675 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg);
1676 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1677 }
1678
1679 bool os::uncommit_memory(char* addr, size_t bytes) {
1680 bool res;
1681 if (MemTracker::tracking_level() > NMT_minimal) {
1682 Tracker tkr = MemTracker::get_virtual_memory_uncommit_tracker();
1683 res = pd_uncommit_memory(addr, bytes);
1684 if (res) {
1685 tkr.record((address)addr, bytes);
1686 }
1687 } else {
1688 res = pd_uncommit_memory(addr, bytes);
1689 }
1690 return res;
1691 }
1692
1693 bool os::release_memory(char* addr, size_t bytes) {
1694 bool res;
1695 if (MemTracker::tracking_level() > NMT_minimal) {
1696 Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
1697 res = pd_release_memory(addr, bytes);
1698 if (res) {
1699 tkr.record((address)addr, bytes);
1700 }
1701 } else {
1702 res = pd_release_memory(addr, bytes);
1703 }
1704 return res;
1705 }
1706
1707
1708 char* os::map_memory(int fd, const char* file_name, size_t file_offset,
1709 char *addr, size_t bytes, bool read_only,
1710 bool allow_exec) {
1711 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec);
1712 if (result != NULL) {
1713 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC);
1714 }
1715 return result;
1716 }
1717
1718 char* os::remap_memory(int fd, const char* file_name, size_t file_offset,
1719 char *addr, size_t bytes, bool read_only,
1720 bool allow_exec) {
1721 return pd_remap_memory(fd, file_name, file_offset, addr, bytes,
1722 read_only, allow_exec);
1723 }
1724
1725 bool os::unmap_memory(char *addr, size_t bytes) {
1726 bool result;
1727 if (MemTracker::tracking_level() > NMT_minimal) {
1728 Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
1729 result = pd_unmap_memory(addr, bytes);
1730 if (result) {
1731 tkr.record((address)addr, bytes);
1732 }
1733 } else {
1734 result = pd_unmap_memory(addr, bytes);
1735 }
1736 return result;
1737 }
1738
1739 void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) {
1740 pd_free_memory(addr, bytes, alignment_hint);
1741 }
1742
1743 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
1744 pd_realign_memory(addr, bytes, alignment_hint);
1745 }
1746
1747 #ifndef TARGET_OS_FAMILY_windows
1748 /* try to switch state from state "from" to state "to"
1749 * returns the state set after the method is complete
1750 */
1751 os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from,
1752 os::SuspendResume::State to)
1753 {
1754 os::SuspendResume::State result =
1755 (os::SuspendResume::State) Atomic::cmpxchg((jint) to, (jint *) &_state, (jint) from);
1756 if (result == from) {
1757 // success
1758 return to;
1759 }
1760 return result;
1761 }
1762 #endif
1763
1764 /////////////// Unit tests ///////////////
1765
1766 #ifndef PRODUCT
1767
1768 #define assert_eq(a,b) assert(a == b, err_msg(SIZE_FORMAT " != " SIZE_FORMAT, a, b))
1769
1770 class TestOS : AllStatic {
1771 static size_t small_page_size() {
1772 return os::vm_page_size();
1773 }
1774
1775 static size_t large_page_size() {
1776 const size_t large_page_size_example = 4 * M;
1777 return os::page_size_for_region(large_page_size_example, 1);
1778 }
1779
1780 static void test_page_size_for_region() {
1781 if (UseLargePages) {
1782 const size_t small_page = small_page_size();
1783 const size_t large_page = large_page_size();
1784
1785 if (large_page > small_page) {
1786 size_t num_small_pages_in_large = large_page / small_page;
1787 size_t page = os::page_size_for_region(large_page, num_small_pages_in_large);
1788
1789 assert_eq(page, small_page);
1790 }
1791 }
1792 }
1793
1794 static void test_page_size_for_region_alignment() {
1795 if (UseLargePages) {
1796 const size_t small_page = small_page_size();
1797 const size_t large_page = large_page_size();
1798 if (large_page > small_page) {
1799 const size_t unaligned_region = large_page + 17;
1800 size_t page = os::page_size_for_region(unaligned_region, 1);
1801 assert_eq(page, small_page);
1802
1803 const size_t num_pages = 5;
1804 const size_t aligned_region = large_page * num_pages;
1805 page = os::page_size_for_region(aligned_region, num_pages);
1806 assert_eq(page, large_page);
1807 }
1808 }
1809 }
1810
1811 public:
1812 static void run_tests() {
1813 test_page_size_for_region();
1814 test_page_size_for_region_alignment();
1815 }
1816 };
1817
1818 void TestOS_test() {
1819 TestOS::run_tests();
1820 }
1821
1822 #endif // PRODUCT