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/icBuffer.hpp"
31 #include "code/vtableStubs.hpp"
32 #include "gc_implementation/shared/vmGCOperations.hpp"
33 #include "interpreter/interpreter.hpp"
34 #include "memory/allocation.inline.hpp"
35 #ifdef ASSERT
36 #include "memory/guardedMemory.hpp"
37 #endif
38 #include "oops/oop.inline.hpp"
39 #include "prims/jvm.h"
40 #include "prims/jvm_misc.hpp"
41 #include "prims/privilegedStack.hpp"
42 #include "runtime/arguments.hpp"
43 #include "runtime/frame.inline.hpp"
44 #include "runtime/interfaceSupport.hpp"
45 #include "runtime/java.hpp"
46 #include "runtime/javaCalls.hpp"
47 #include "runtime/mutexLocker.hpp"
48 #include "runtime/os.hpp"
49 #include "runtime/stubRoutines.hpp"
50 #include "runtime/thread.inline.hpp"
51 #include "services/attachListener.hpp"
52 #include "services/nmtCommon.hpp"
53 #include "services/mallocTracker.hpp"
54 #include "services/memTracker.hpp"
55 #include "services/threadService.hpp"
56 #include "utilities/defaultStream.hpp"
57 #include "utilities/events.hpp"
58 #ifdef TARGET_OS_FAMILY_linux
59 # include "os_linux.inline.hpp"
60 #endif
61 #ifdef TARGET_OS_FAMILY_solaris
62 # include "os_solaris.inline.hpp"
63 #endif
64 #ifdef TARGET_OS_FAMILY_windows
65 # include "os_windows.inline.hpp"
66 #endif
67 #ifdef TARGET_OS_FAMILY_bsd
68 # include "os_bsd.inline.hpp"
69 #endif
70
71 # include <signal.h>
72
73 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
74
75 OSThread* os::_starting_thread = NULL;
76 address os::_polling_page = NULL;
77 volatile int32_t* os::_mem_serialize_page = NULL;
78 uintptr_t os::_serialize_page_mask = 0;
79 long os::_rand_seed = 1;
80 int os::_processor_count = 0;
81 size_t os::_page_sizes[os::page_sizes_max];
82
83 #ifndef PRODUCT
84 julong os::num_mallocs = 0; // # of calls to malloc/realloc
85 julong os::alloc_bytes = 0; // # of bytes allocated
86 julong os::num_frees = 0; // # of calls to free
87 julong os::free_bytes = 0; // # of bytes freed
88 #endif
89
90 static juint cur_malloc_words = 0; // current size for MallocMaxTestWords
91
92 void os_init_globals() {
93 // Called from init_globals().
94 // See Threads::create_vm() in thread.cpp, and init.cpp.
95 os::init_globals();
96 }
97
98 // Fill in buffer with current local time as an ISO-8601 string.
99 // E.g., yyyy-mm-ddThh:mm:ss-zzzz.
100 // Returns buffer, or NULL if it failed.
101 // This would mostly be a call to
102 // strftime(...., "%Y-%m-%d" "T" "%H:%M:%S" "%z", ....)
103 // except that on Windows the %z behaves badly, so we do it ourselves.
104 // Also, people wanted milliseconds on there,
105 // and strftime doesn't do milliseconds.
106 char* os::iso8601_time(char* buffer, size_t buffer_length) {
107 // Output will be of the form "YYYY-MM-DDThh:mm:ss.mmm+zzzz\0"
108 // 1 2
109 // 12345678901234567890123456789
110 static const char* iso8601_format =
111 "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d";
112 static const size_t needed_buffer = 29;
113
114 // Sanity check the arguments
115 if (buffer == NULL) {
116 assert(false, "NULL buffer");
117 return NULL;
118 }
119 if (buffer_length < needed_buffer) {
120 assert(false, "buffer_length too small");
121 return NULL;
122 }
123 // Get the current time
124 jlong milliseconds_since_19700101 = javaTimeMillis();
125 const int milliseconds_per_microsecond = 1000;
126 const time_t seconds_since_19700101 =
127 milliseconds_since_19700101 / milliseconds_per_microsecond;
128 const int milliseconds_after_second =
129 milliseconds_since_19700101 % milliseconds_per_microsecond;
130 // Convert the time value to a tm and timezone variable
131 struct tm time_struct;
132 if (localtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
133 assert(false, "Failed localtime_pd");
134 return NULL;
135 }
136 #if defined(_ALLBSD_SOURCE)
137 const time_t zone = (time_t) time_struct.tm_gmtoff;
138 #else
139 const time_t zone = timezone;
140 #endif
141
142 // If daylight savings time is in effect,
143 // we are 1 hour East of our time zone
144 const time_t seconds_per_minute = 60;
145 const time_t minutes_per_hour = 60;
146 const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour;
147 time_t UTC_to_local = zone;
148 if (time_struct.tm_isdst > 0) {
149 UTC_to_local = UTC_to_local - seconds_per_hour;
150 }
151 // Compute the time zone offset.
152 // localtime_pd() sets timezone to the difference (in seconds)
153 // between UTC and and local time.
154 // ISO 8601 says we need the difference between local time and UTC,
155 // we change the sign of the localtime_pd() result.
156 const time_t local_to_UTC = -(UTC_to_local);
157 // Then we have to figure out if if we are ahead (+) or behind (-) UTC.
158 char sign_local_to_UTC = '+';
159 time_t abs_local_to_UTC = local_to_UTC;
160 if (local_to_UTC < 0) {
161 sign_local_to_UTC = '-';
162 abs_local_to_UTC = -(abs_local_to_UTC);
163 }
164 // Convert time zone offset seconds to hours and minutes.
165 const time_t zone_hours = (abs_local_to_UTC / seconds_per_hour);
166 const time_t zone_min =
167 ((abs_local_to_UTC % seconds_per_hour) / seconds_per_minute);
168
169 // Print an ISO 8601 date and time stamp into the buffer
170 const int year = 1900 + time_struct.tm_year;
171 const int month = 1 + time_struct.tm_mon;
172 const int printed = jio_snprintf(buffer, buffer_length, iso8601_format,
173 year,
174 month,
175 time_struct.tm_mday,
176 time_struct.tm_hour,
177 time_struct.tm_min,
178 time_struct.tm_sec,
179 milliseconds_after_second,
180 sign_local_to_UTC,
181 zone_hours,
182 zone_min);
183 if (printed == 0) {
184 assert(false, "Failed jio_printf");
185 return NULL;
186 }
187 return buffer;
188 }
189
190 OSReturn os::set_priority(Thread* thread, ThreadPriority p) {
191 #ifdef ASSERT
192 if (!(!thread->is_Java_thread() ||
193 Thread::current() == thread ||
194 Threads_lock->owned_by_self()
195 || thread->is_Compiler_thread()
196 )) {
197 assert(false, "possibility of dangling Thread pointer");
198 }
199 #endif
200
201 if (p >= MinPriority && p <= MaxPriority) {
202 int priority = java_to_os_priority[p];
203 return set_native_priority(thread, priority);
204 } else {
205 assert(false, "Should not happen");
206 return OS_ERR;
207 }
208 }
209
210 // The mapping from OS priority back to Java priority may be inexact because
211 // Java priorities can map M:1 with native priorities. If you want the definite
212 // Java priority then use JavaThread::java_priority()
213 OSReturn os::get_priority(const Thread* const thread, ThreadPriority& priority) {
214 int p;
215 int os_prio;
216 OSReturn ret = get_native_priority(thread, &os_prio);
217 if (ret != OS_OK) return ret;
218
219 if (java_to_os_priority[MaxPriority] > java_to_os_priority[MinPriority]) {
220 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] > os_prio; p--) ;
221 } else {
222 // niceness values are in reverse order
223 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] < os_prio; p--) ;
224 }
225 priority = (ThreadPriority)p;
226 return OS_OK;
227 }
228
229
230 // --------------------- sun.misc.Signal (optional) ---------------------
231
232
233 // SIGBREAK is sent by the keyboard to query the VM state
234 #ifndef SIGBREAK
235 #define SIGBREAK SIGQUIT
236 #endif
237
238 // sigexitnum_pd is a platform-specific special signal used for terminating the Signal thread.
239
240
241 static void signal_thread_entry(JavaThread* thread, TRAPS) {
242 os::set_priority(thread, NearMaxPriority);
243 while (true) {
244 int sig;
245 {
246 // FIXME : Currently we have not decieded what should be the status
247 // for this java thread blocked here. Once we decide about
248 // that we should fix this.
249 sig = os::signal_wait();
250 }
251 if (sig == os::sigexitnum_pd()) {
252 // Terminate the signal thread
253 return;
254 }
255
256 switch (sig) {
257 case SIGBREAK: {
258 // Check if the signal is a trigger to start the Attach Listener - in that
259 // case don't print stack traces.
260 if (!DisableAttachMechanism && AttachListener::is_init_trigger()) {
261 continue;
262 }
263 // Print stack traces
264 // Any SIGBREAK operations added here should make sure to flush
265 // the output stream (e.g. tty->flush()) after output. See 4803766.
266 // Each module also prints an extra carriage return after its output.
267 VM_PrintThreads op;
268 VMThread::execute(&op);
269 VM_PrintJNI jni_op;
270 VMThread::execute(&jni_op);
271 VM_FindDeadlocks op1(tty);
272 VMThread::execute(&op1);
273 Universe::print_heap_at_SIGBREAK();
274 if (PrintClassHistogram) {
275 VM_GC_HeapInspection op1(gclog_or_tty, true /* force full GC before heap inspection */);
276 VMThread::execute(&op1);
277 }
278 if (JvmtiExport::should_post_data_dump()) {
279 JvmtiExport::post_data_dump();
280 }
281 break;
282 }
283 default: {
284 // Dispatch the signal to java
285 HandleMark hm(THREAD);
286 Klass* k = SystemDictionary::resolve_or_null(vmSymbols::sun_misc_Signal(), THREAD);
287 KlassHandle klass (THREAD, k);
288 if (klass.not_null()) {
289 JavaValue result(T_VOID);
290 JavaCallArguments args;
291 args.push_int(sig);
292 JavaCalls::call_static(
293 &result,
294 klass,
295 vmSymbols::dispatch_name(),
296 vmSymbols::int_void_signature(),
297 &args,
298 THREAD
299 );
300 }
301 if (HAS_PENDING_EXCEPTION) {
302 // tty is initialized early so we don't expect it to be null, but
303 // if it is we can't risk doing an initialization that might
304 // trigger additional out-of-memory conditions
305 if (tty != NULL) {
306 char klass_name[256];
307 char tmp_sig_name[16];
308 const char* sig_name = "UNKNOWN";
309 InstanceKlass::cast(PENDING_EXCEPTION->klass())->
310 name()->as_klass_external_name(klass_name, 256);
311 if (os::exception_name(sig, tmp_sig_name, 16) != NULL)
312 sig_name = tmp_sig_name;
313 warning("Exception %s occurred dispatching signal %s to handler"
314 "- the VM may need to be forcibly terminated",
315 klass_name, sig_name );
316 }
317 CLEAR_PENDING_EXCEPTION;
318 }
319 }
320 }
321 }
322 }
323
324 void os::init_before_ergo() {
325 // We need to initialize large page support here because ergonomics takes some
326 // decisions depending on large page support and the calculated large page size.
327 large_page_init();
328 }
329
330 void os::signal_init() {
331 if (!ReduceSignalUsage) {
332 // Setup JavaThread for processing signals
333 EXCEPTION_MARK;
334 Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(), true, CHECK);
335 instanceKlassHandle klass (THREAD, k);
336 instanceHandle thread_oop = klass->allocate_instance_handle(CHECK);
337
338 const char thread_name[] = "Signal Dispatcher";
339 Handle string = java_lang_String::create_from_str(thread_name, CHECK);
340
341 // Initialize thread_oop to put it into the system threadGroup
342 Handle thread_group (THREAD, Universe::system_thread_group());
343 JavaValue result(T_VOID);
344 JavaCalls::call_special(&result, thread_oop,
345 klass,
346 vmSymbols::object_initializer_name(),
347 vmSymbols::threadgroup_string_void_signature(),
348 thread_group,
349 string,
350 CHECK);
351
352 KlassHandle group(THREAD, SystemDictionary::ThreadGroup_klass());
353 JavaCalls::call_special(&result,
354 thread_group,
355 group,
356 vmSymbols::add_method_name(),
357 vmSymbols::thread_void_signature(),
358 thread_oop, // ARG 1
359 CHECK);
360
361 os::signal_init_pd();
362
363 { MutexLocker mu(Threads_lock);
364 JavaThread* signal_thread = new JavaThread(&signal_thread_entry);
365
366 // At this point it may be possible that no osthread was created for the
367 // JavaThread due to lack of memory. We would have to throw an exception
368 // in that case. However, since this must work and we do not allow
369 // exceptions anyway, check and abort if this fails.
370 if (signal_thread == NULL || signal_thread->osthread() == NULL) {
371 vm_exit_during_initialization("java.lang.OutOfMemoryError",
372 "unable to create new native thread");
373 }
374
375 java_lang_Thread::set_thread(thread_oop(), signal_thread);
376 java_lang_Thread::set_priority(thread_oop(), NearMaxPriority);
377 java_lang_Thread::set_daemon(thread_oop());
378
379 signal_thread->set_threadObj(thread_oop());
380 Threads::add(signal_thread);
381 Thread::start(signal_thread);
382 }
383 // Handle ^BREAK
384 os::signal(SIGBREAK, os::user_handler());
385 }
386 }
387
388
389 void os::terminate_signal_thread() {
390 if (!ReduceSignalUsage)
391 signal_notify(sigexitnum_pd());
392 }
393
394
395 // --------------------- loading libraries ---------------------
396
397 typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *);
398 extern struct JavaVM_ main_vm;
399
400 static void* _native_java_library = NULL;
401
402 void* os::native_java_library() {
403 if (_native_java_library == NULL) {
404 char buffer[JVM_MAXPATHLEN];
405 char ebuf[1024];
406
407 // Try to load verify dll first. In 1.3 java dll depends on it and is not
408 // always able to find it when the loading executable is outside the JDK.
409 // In order to keep working with 1.2 we ignore any loading errors.
410 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
411 "verify")) {
412 dll_load(buffer, ebuf, sizeof(ebuf));
413 }
414
415 // Load java dll
416 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
417 "java")) {
418 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf));
419 }
420 if (_native_java_library == NULL) {
421 vm_exit_during_initialization("Unable to load native library", ebuf);
422 }
423
424 #if defined(__OpenBSD__)
425 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so
426 // ignore errors
427 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
428 "net")) {
429 dll_load(buffer, ebuf, sizeof(ebuf));
430 }
431 #endif
432 }
433 static jboolean onLoaded = JNI_FALSE;
434 if (onLoaded) {
435 // We may have to wait to fire OnLoad until TLS is initialized.
436 if (ThreadLocalStorage::is_initialized()) {
437 // The JNI_OnLoad handling is normally done by method load in
438 // java.lang.ClassLoader$NativeLibrary, but the VM loads the base library
439 // explicitly so we have to check for JNI_OnLoad as well
440 const char *onLoadSymbols[] = JNI_ONLOAD_SYMBOLS;
441 JNI_OnLoad_t JNI_OnLoad = CAST_TO_FN_PTR(
442 JNI_OnLoad_t, dll_lookup(_native_java_library, onLoadSymbols[0]));
443 if (JNI_OnLoad != NULL) {
444 JavaThread* thread = JavaThread::current();
445 ThreadToNativeFromVM ttn(thread);
446 HandleMark hm(thread);
447 jint ver = (*JNI_OnLoad)(&main_vm, NULL);
448 onLoaded = JNI_TRUE;
449 if (!Threads::is_supported_jni_version_including_1_1(ver)) {
450 vm_exit_during_initialization("Unsupported JNI version");
451 }
452 }
453 }
454 }
455 return _native_java_library;
456 }
457
458 /*
459 * Support for finding Agent_On(Un)Load/Attach<_lib_name> if it exists.
460 * If check_lib == true then we are looking for an
461 * Agent_OnLoad_lib_name or Agent_OnAttach_lib_name function to determine if
462 * this library is statically linked into the image.
463 * If check_lib == false then we will look for the appropriate symbol in the
464 * executable if agent_lib->is_static_lib() == true or in the shared library
465 * referenced by 'handle'.
466 */
467 void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib,
468 const char *syms[], size_t syms_len) {
469 assert(agent_lib != NULL, "sanity check");
470 const char *lib_name;
471 void *handle = agent_lib->os_lib();
472 void *entryName = NULL;
473 char *agent_function_name;
474 size_t i;
475
476 // If checking then use the agent name otherwise test is_static_lib() to
477 // see how to process this lookup
478 lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL);
479 for (i = 0; i < syms_len; i++) {
480 agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path());
481 if (agent_function_name == NULL) {
482 break;
483 }
484 entryName = dll_lookup(handle, agent_function_name);
485 FREE_C_HEAP_ARRAY(char, agent_function_name, mtThread);
486 if (entryName != NULL) {
487 break;
488 }
489 }
490 return entryName;
491 }
492
493 // See if the passed in agent is statically linked into the VM image.
494 bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
495 size_t syms_len) {
496 void *ret;
497 void *proc_handle;
498 void *save_handle;
499
500 assert(agent_lib != NULL, "sanity check");
501 if (agent_lib->name() == NULL) {
502 return false;
503 }
504 proc_handle = get_default_process_handle();
505 // Check for Agent_OnLoad/Attach_lib_name function
506 save_handle = agent_lib->os_lib();
507 // We want to look in this process' symbol table.
508 agent_lib->set_os_lib(proc_handle);
509 ret = find_agent_function(agent_lib, true, syms, syms_len);
510 if (ret != NULL) {
511 // Found an entry point like Agent_OnLoad_lib_name so we have a static agent
512 agent_lib->set_valid();
513 agent_lib->set_static_lib(true);
514 return true;
515 }
516 agent_lib->set_os_lib(save_handle);
517 return false;
518 }
519
520 // --------------------- heap allocation utilities ---------------------
521
522 char *os::strdup(const char *str, MEMFLAGS flags) {
523 size_t size = strlen(str);
524 char *dup_str = (char *)malloc(size + 1, flags);
525 if (dup_str == NULL) return NULL;
526 strcpy(dup_str, str);
527 return dup_str;
528 }
529
530
531
532 #define paranoid 0 /* only set to 1 if you suspect checking code has bug */
533
534 #ifdef ASSERT
535 static void verify_memory(void* ptr) {
536 GuardedMemory guarded(ptr);
537 if (!guarded.verify_guards()) {
538 tty->print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees);
539 tty->print_cr("## memory stomp:");
540 guarded.print_on(tty);
541 fatal("memory stomping error");
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 #ifdef ASSERT
575 // checking for the WatcherThread and crash_protection first
576 // since os::malloc can be called when the libjvm.{dll,so} is
577 // first loaded and we don't have a thread yet.
578 // try to find the thread after we see that the watcher thread
579 // exists and has crash protection.
580 WatcherThread *wt = WatcherThread::watcher_thread();
581 if (wt != NULL && wt->has_crash_protection()) {
582 Thread* thread = ThreadLocalStorage::get_thread_slow();
583 if (thread == wt) {
584 assert(!wt->has_crash_protection(),
585 "Can't malloc with crash protection from WatcherThread");
586 }
587 }
588 #endif
589
590 if (size == 0) {
591 // return a valid pointer if size is zero
592 // if NULL is returned the calling functions assume out of memory.
593 size = 1;
594 }
595
596 // NMT support
597 NMT_TrackingLevel level = MemTracker::tracking_level();
598 size_t nmt_header_size = MemTracker::malloc_header_size(level);
599
600 #ifndef ASSERT
601 const size_t alloc_size = size + nmt_header_size;
602 #else
603 const size_t alloc_size = GuardedMemory::get_total_size(size + nmt_header_size);
604 if (size + nmt_header_size > alloc_size) { // Check for rollover.
605 return NULL;
606 }
607 #endif
608
609 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
610
611 u_char* ptr;
612 if (MallocMaxTestWords > 0) {
613 ptr = testMalloc(alloc_size);
614 } else {
615 ptr = (u_char*)::malloc(alloc_size);
616 }
617
618 #ifdef ASSERT
619 if (ptr == NULL) {
620 return NULL;
621 }
622 // Wrap memory with guard
623 GuardedMemory guarded(ptr, size + nmt_header_size);
624 ptr = guarded.get_user_ptr();
625 #endif
626 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) {
627 tty->print_cr("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr);
628 breakpoint();
629 }
630 debug_only(if (paranoid) verify_memory(ptr));
631 if (PrintMalloc && tty != NULL) {
632 tty->print_cr("os::malloc " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr);
633 }
634
635 // we do not track guard memory
636 return MemTracker::record_malloc((address)ptr, size, memflags, stack, level);
637 }
638
639 void* os::realloc(void *memblock, size_t size, MEMFLAGS flags) {
640 return os::realloc(memblock, size, flags, CALLER_PC);
641 }
642
643 void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, const NativeCallStack& stack) {
644
645 #ifndef ASSERT
646 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
647 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
648 // NMT support
649 void* membase = MemTracker::record_free(memblock);
650 NMT_TrackingLevel level = MemTracker::tracking_level();
651 size_t nmt_header_size = MemTracker::malloc_header_size(level);
652 void* ptr = ::realloc(membase, size + nmt_header_size);
653 return MemTracker::record_malloc(ptr, size, memflags, stack, level);
654 #else
655 if (memblock == NULL) {
656 return os::malloc(size, memflags, stack);
657 }
658 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
659 tty->print_cr("os::realloc caught " PTR_FORMAT, memblock);
660 breakpoint();
661 }
662 // NMT support
663 void* membase = MemTracker::malloc_base(memblock);
664 verify_memory(membase);
665 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
666 if (size == 0) {
667 return NULL;
668 }
669 // always move the block
670 void* ptr = os::malloc(size, memflags, stack);
671 if (PrintMalloc) {
672 tty->print_cr("os::remalloc " SIZE_FORMAT " bytes, " PTR_FORMAT " --> " PTR_FORMAT, size, memblock, ptr);
673 }
674 // Copy to new memory if malloc didn't fail
675 if ( ptr != NULL ) {
676 GuardedMemory guarded(MemTracker::malloc_base(memblock));
677 // Guard's user data contains NMT header
678 size_t memblock_size = guarded.get_user_size() - MemTracker::malloc_header_size(memblock);
679 memcpy(ptr, memblock, MIN2(size, memblock_size));
680 if (paranoid) verify_memory(MemTracker::malloc_base(ptr));
681 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) {
682 tty->print_cr("os::realloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr);
683 breakpoint();
684 }
685 os::free(memblock);
686 }
687 return ptr;
688 #endif
689 }
690
691
692 void os::free(void *memblock, MEMFLAGS memflags) {
693 NOT_PRODUCT(inc_stat_counter(&num_frees, 1));
694 #ifdef ASSERT
695 if (memblock == NULL) return;
696 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
697 if (tty != NULL) tty->print_cr("os::free caught " PTR_FORMAT, memblock);
698 breakpoint();
699 }
700 void* membase = MemTracker::record_free(memblock);
701 verify_memory(membase);
702 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
703
704 GuardedMemory guarded(membase);
705 size_t size = guarded.get_user_size();
706 inc_stat_counter(&free_bytes, size);
707 membase = guarded.release_for_freeing();
708 if (PrintMalloc && tty != NULL) {
709 fprintf(stderr, "os::free " SIZE_FORMAT " bytes --> " PTR_FORMAT "\n", size, (uintptr_t)membase);
710 }
711 ::free(membase);
712 #else
713 void* membase = MemTracker::record_free(memblock);
714 ::free(membase);
715 #endif
716 }
717
718 void os::init_random(long initval) {
719 _rand_seed = initval;
720 }
721
722
723 long os::random() {
724 /* standard, well-known linear congruential random generator with
725 * next_rand = (16807*seed) mod (2**31-1)
726 * see
727 * (1) "Random Number Generators: Good Ones Are Hard to Find",
728 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988),
729 * (2) "Two Fast Implementations of the 'Minimal Standard' Random
730 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88.
731 */
732 const long a = 16807;
733 const unsigned long m = 2147483647;
734 const long q = m / a; assert(q == 127773, "weird math");
735 const long r = m % a; assert(r == 2836, "weird math");
736
737 // compute az=2^31p+q
738 unsigned long lo = a * (long)(_rand_seed & 0xFFFF);
739 unsigned long hi = a * (long)((unsigned long)_rand_seed >> 16);
740 lo += (hi & 0x7FFF) << 16;
741
742 // if q overflowed, ignore the overflow and increment q
743 if (lo > m) {
744 lo &= m;
745 ++lo;
746 }
747 lo += hi >> 15;
748
749 // if (p+q) overflowed, ignore the overflow and increment (p+q)
750 if (lo > m) {
751 lo &= m;
752 ++lo;
753 }
754 return (_rand_seed = lo);
755 }
756
757 // The INITIALIZED state is distinguished from the SUSPENDED state because the
758 // conditions in which a thread is first started are different from those in which
759 // a suspension is resumed. These differences make it hard for us to apply the
760 // tougher checks when starting threads that we want to do when resuming them.
761 // However, when start_thread is called as a result of Thread.start, on a Java
762 // thread, the operation is synchronized on the Java Thread object. So there
763 // cannot be a race to start the thread and hence for the thread to exit while
764 // we are working on it. Non-Java threads that start Java threads either have
765 // to do so in a context in which races are impossible, or should do appropriate
766 // locking.
767
768 void os::start_thread(Thread* thread) {
769 // guard suspend/resume
770 MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag);
771 OSThread* osthread = thread->osthread();
772 osthread->set_state(RUNNABLE);
773 pd_start_thread(thread);
774 }
775
776 //---------------------------------------------------------------------------
777 // Helper functions for fatal error handler
778
779 void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) {
780 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking");
781
782 int cols = 0;
783 int cols_per_line = 0;
784 switch (unitsize) {
785 case 1: cols_per_line = 16; break;
786 case 2: cols_per_line = 8; break;
787 case 4: cols_per_line = 4; break;
788 case 8: cols_per_line = 2; break;
789 default: return;
790 }
791
792 address p = start;
793 st->print(PTR_FORMAT ": ", start);
794 while (p < end) {
795 switch (unitsize) {
796 case 1: st->print("%02x", *(u1*)p); break;
797 case 2: st->print("%04x", *(u2*)p); break;
798 case 4: st->print("%08x", *(u4*)p); break;
799 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break;
800 }
801 p += unitsize;
802 cols++;
803 if (cols >= cols_per_line && p < end) {
804 cols = 0;
805 st->cr();
806 st->print(PTR_FORMAT ": ", p);
807 } else {
808 st->print(" ");
809 }
810 }
811 st->cr();
812 }
813
814 void os::print_environment_variables(outputStream* st, const char** env_list,
815 char* buffer, int len) {
816 if (env_list) {
817 st->print_cr("Environment Variables:");
818
819 for (int i = 0; env_list[i] != NULL; i++) {
820 if (getenv(env_list[i], buffer, len)) {
821 st->print("%s", env_list[i]);
822 st->print("=");
823 st->print_cr("%s", buffer);
824 }
825 }
826 }
827 }
828
829 void os::print_cpu_info(outputStream* st) {
830 // cpu
831 st->print("CPU:");
832 st->print("total %d", os::processor_count());
833 // It's not safe to query number of active processors after crash
834 // st->print("(active %d)", os::active_processor_count());
835 st->print(" %s", VM_Version::cpu_features());
836 st->cr();
837 pd_print_cpu_info(st);
838 }
839
840 void os::print_date_and_time(outputStream *st) {
841 const int secs_per_day = 86400;
842 const int secs_per_hour = 3600;
843 const int secs_per_min = 60;
844
845 time_t tloc;
846 (void)time(&tloc);
847 st->print("time: %s", ctime(&tloc)); // ctime adds newline.
848
849 double t = os::elapsedTime();
850 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in
851 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int
852 // before printf. We lost some precision, but who cares?
853 int eltime = (int)t; // elapsed time in seconds
854
855 // print elapsed time in a human-readable format:
856 int eldays = eltime / secs_per_day;
857 int day_secs = eldays * secs_per_day;
858 int elhours = (eltime - day_secs) / secs_per_hour;
859 int hour_secs = elhours * secs_per_hour;
860 int elmins = (eltime - day_secs - hour_secs) / secs_per_min;
861 int minute_secs = elmins * secs_per_min;
862 int elsecs = (eltime - day_secs - hour_secs - minute_secs);
863 st->print_cr("elapsed time: %d seconds (%dd %dh %dm %ds)", eltime, eldays, elhours, elmins, elsecs);
864 }
865
866 // moved from debug.cpp (used to be find()) but still called from there
867 // The verbose parameter is only set by the debug code in one case
868 void os::print_location(outputStream* st, intptr_t x, bool verbose) {
869 address addr = (address)x;
870 CodeBlob* b = CodeCache::find_blob_unsafe(addr);
871 if (b != NULL) {
872 if (b->is_buffer_blob()) {
873 // the interpreter is generated into a buffer blob
874 InterpreterCodelet* i = Interpreter::codelet_containing(addr);
875 if (i != NULL) {
876 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an Interpreter codelet", addr, (int)(addr - i->code_begin()));
877 i->print_on(st);
878 return;
879 }
880 if (Interpreter::contains(addr)) {
881 st->print_cr(INTPTR_FORMAT " is pointing into interpreter code"
882 " (not bytecode specific)", addr);
883 return;
884 }
885 //
886 if (AdapterHandlerLibrary::contains(b)) {
887 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an AdapterHandler", addr, (int)(addr - b->code_begin()));
888 AdapterHandlerLibrary::print_handler_on(st, b);
889 }
890 // the stubroutines are generated into a buffer blob
891 StubCodeDesc* d = StubCodeDesc::desc_for(addr);
892 if (d != NULL) {
893 st->print_cr(INTPTR_FORMAT " is at begin+%d in a stub", addr, (int)(addr - d->begin()));
894 d->print_on(st);
895 st->cr();
896 return;
897 }
898 if (StubRoutines::contains(addr)) {
899 st->print_cr(INTPTR_FORMAT " is pointing to an (unnamed) "
900 "stub routine", addr);
901 return;
902 }
903 // the InlineCacheBuffer is using stubs generated into a buffer blob
904 if (InlineCacheBuffer::contains(addr)) {
905 st->print_cr(INTPTR_FORMAT " is pointing into InlineCacheBuffer", addr);
906 return;
907 }
908 VtableStub* v = VtableStubs::stub_containing(addr);
909 if (v != NULL) {
910 st->print_cr(INTPTR_FORMAT " is at entry_point+%d in a vtable stub", addr, (int)(addr - v->entry_point()));
911 v->print_on(st);
912 st->cr();
913 return;
914 }
915 }
916 nmethod* nm = b->as_nmethod_or_null();
917 if (nm != NULL) {
918 ResourceMark rm;
919 st->print(INTPTR_FORMAT " is at entry_point+%d in (nmethod*)" INTPTR_FORMAT,
920 addr, (int)(addr - nm->entry_point()), nm);
921 if (verbose) {
922 st->print(" for ");
923 nm->method()->print_value_on(st);
924 }
925 st->cr();
926 nm->print_nmethod(verbose);
927 return;
928 }
929 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in ", addr, (int)(addr - b->code_begin()));
930 b->print_on(st);
931 return;
932 }
933
934 if (Universe::heap()->is_in(addr)) {
935 HeapWord* p = Universe::heap()->block_start(addr);
936 bool print = false;
937 // If we couldn't find it it just may mean that heap wasn't parseable
938 // See if we were just given an oop directly
939 if (p != NULL && Universe::heap()->block_is_obj(p)) {
940 print = true;
941 } else if (p == NULL && ((oopDesc*)addr)->is_oop()) {
942 p = (HeapWord*) addr;
943 print = true;
944 }
945 if (print) {
946 if (p == (HeapWord*) addr) {
947 st->print_cr(INTPTR_FORMAT " is an oop", addr);
948 } else {
949 st->print_cr(INTPTR_FORMAT " is pointing into object: " INTPTR_FORMAT, addr, p);
950 }
951 oop(p)->print_on(st);
952 return;
953 }
954 } else {
955 if (Universe::heap()->is_in_reserved(addr)) {
956 st->print_cr(INTPTR_FORMAT " is an unallocated location "
957 "in the heap", addr);
958 return;
959 }
960 }
961 if (JNIHandles::is_global_handle((jobject) addr)) {
962 st->print_cr(INTPTR_FORMAT " is a global jni handle", addr);
963 return;
964 }
965 if (JNIHandles::is_weak_global_handle((jobject) addr)) {
966 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", addr);
967 return;
968 }
969 #ifndef PRODUCT
970 // we don't keep the block list in product mode
971 if (JNIHandleBlock::any_contains((jobject) addr)) {
972 st->print_cr(INTPTR_FORMAT " is a local jni handle", addr);
973 return;
974 }
975 #endif
976
977 for(JavaThread *thread = Threads::first(); thread; thread = thread->next()) {
978 // Check for privilege stack
979 if (thread->privileged_stack_top() != NULL &&
980 thread->privileged_stack_top()->contains(addr)) {
981 st->print_cr(INTPTR_FORMAT " is pointing into the privilege stack "
982 "for thread: " INTPTR_FORMAT, addr, thread);
983 if (verbose) thread->print_on(st);
984 return;
985 }
986 // If the addr is a java thread print information about that.
987 if (addr == (address)thread) {
988 if (verbose) {
989 thread->print_on(st);
990 } else {
991 st->print_cr(INTPTR_FORMAT " is a thread", addr);
992 }
993 return;
994 }
995 // If the addr is in the stack region for this thread then report that
996 // and print thread info
997 if (thread->stack_base() >= addr &&
998 addr > (thread->stack_base() - thread->stack_size())) {
999 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: "
1000 INTPTR_FORMAT, addr, thread);
1001 if (verbose) thread->print_on(st);
1002 return;
1003 }
1004
1005 }
1006
1007 // Check if in metaspace and print types that have vptrs (only method now)
1008 if (Metaspace::contains(addr)) {
1009 if (Method::has_method_vptr((const void*)addr)) {
1010 ((Method*)addr)->print_value_on(st);
1011 st->cr();
1012 } else {
1013 // Use addr->print() from the debugger instead (not here)
1014 st->print_cr(INTPTR_FORMAT " is pointing into metadata", addr);
1015 }
1016 return;
1017 }
1018
1019 // Try an OS specific find
1020 if (os::find(addr, st)) {
1021 return;
1022 }
1023
1024 st->print_cr(INTPTR_FORMAT " is an unknown value", addr);
1025 }
1026
1027 // Looks like all platforms except IA64 can use the same function to check
1028 // if C stack is walkable beyond current frame. The check for fp() is not
1029 // necessary on Sparc, but it's harmless.
1030 bool os::is_first_C_frame(frame* fr) {
1031 #if (defined(IA64) && !defined(AIX)) && !defined(_WIN32)
1032 // On IA64 we have to check if the callers bsp is still valid
1033 // (i.e. within the register stack bounds).
1034 // Notice: this only works for threads created by the VM and only if
1035 // we walk the current stack!!! If we want to be able to walk
1036 // arbitrary other threads, we'll have to somehow store the thread
1037 // object in the frame.
1038 Thread *thread = Thread::current();
1039 if ((address)fr->fp() <=
1040 thread->register_stack_base() HPUX_ONLY(+ 0x0) LINUX_ONLY(+ 0x50)) {
1041 // This check is a little hacky, because on Linux the first C
1042 // frame's ('start_thread') register stack frame starts at
1043 // "register_stack_base + 0x48" while on HPUX, the first C frame's
1044 // ('__pthread_bound_body') register stack frame seems to really
1045 // start at "register_stack_base".
1046 return true;
1047 } else {
1048 return false;
1049 }
1050 #elif defined(IA64) && defined(_WIN32)
1051 return true;
1052 #else
1053 // Load up sp, fp, sender sp and sender fp, check for reasonable values.
1054 // Check usp first, because if that's bad the other accessors may fault
1055 // on some architectures. Ditto ufp second, etc.
1056 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1);
1057 // sp on amd can be 32 bit aligned.
1058 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1);
1059
1060 uintptr_t usp = (uintptr_t)fr->sp();
1061 if ((usp & sp_align_mask) != 0) return true;
1062
1063 uintptr_t ufp = (uintptr_t)fr->fp();
1064 if ((ufp & fp_align_mask) != 0) return true;
1065
1066 uintptr_t old_sp = (uintptr_t)fr->sender_sp();
1067 if ((old_sp & sp_align_mask) != 0) return true;
1068 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true;
1069
1070 uintptr_t old_fp = (uintptr_t)fr->link();
1071 if ((old_fp & fp_align_mask) != 0) return true;
1072 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true;
1073
1074 // stack grows downwards; if old_fp is below current fp or if the stack
1075 // frame is too large, either the stack is corrupted or fp is not saved
1076 // on stack (i.e. on x86, ebp may be used as general register). The stack
1077 // is not walkable beyond current frame.
1078 if (old_fp < ufp) return true;
1079 if (old_fp - ufp > 64 * K) return true;
1080
1081 return false;
1082 #endif
1083 }
1084
1085 #ifdef ASSERT
1086 extern "C" void test_random() {
1087 const double m = 2147483647;
1088 double mean = 0.0, variance = 0.0, t;
1089 long reps = 10000;
1090 unsigned long seed = 1;
1091
1092 tty->print_cr("seed %ld for %ld repeats...", seed, reps);
1093 os::init_random(seed);
1094 long num;
1095 for (int k = 0; k < reps; k++) {
1096 num = os::random();
1097 double u = (double)num / m;
1098 assert(u >= 0.0 && u <= 1.0, "bad random number!");
1099
1100 // calculate mean and variance of the random sequence
1101 mean += u;
1102 variance += (u*u);
1103 }
1104 mean /= reps;
1105 variance /= (reps - 1);
1106
1107 assert(num == 1043618065, "bad seed");
1108 tty->print_cr("mean of the 1st 10000 numbers: %f", mean);
1109 tty->print_cr("variance of the 1st 10000 numbers: %f", variance);
1110 const double eps = 0.0001;
1111 t = fabsd(mean - 0.5018);
1112 assert(t < eps, "bad mean");
1113 t = (variance - 0.3355) < 0.0 ? -(variance - 0.3355) : variance - 0.3355;
1114 assert(t < eps, "bad variance");
1115 }
1116 #endif
1117
1118
1119 // Set up the boot classpath.
1120
1121 char* os::format_boot_path(const char* format_string,
1122 const char* home,
1123 int home_len,
1124 char fileSep,
1125 char pathSep) {
1126 assert((fileSep == '/' && pathSep == ':') ||
1127 (fileSep == '\\' && pathSep == ';'), "unexpected seperator chars");
1128
1129 // Scan the format string to determine the length of the actual
1130 // boot classpath, and handle platform dependencies as well.
1131 int formatted_path_len = 0;
1132 const char* p;
1133 for (p = format_string; *p != 0; ++p) {
1134 if (*p == '%') formatted_path_len += home_len - 1;
1135 ++formatted_path_len;
1136 }
1137
1138 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal);
1139 if (formatted_path == NULL) {
1140 return NULL;
1141 }
1142
1143 // Create boot classpath from format, substituting separator chars and
1144 // java home directory.
1145 char* q = formatted_path;
1146 for (p = format_string; *p != 0; ++p) {
1147 switch (*p) {
1148 case '%':
1149 strcpy(q, home);
1150 q += home_len;
1151 break;
1152 case '/':
1153 *q++ = fileSep;
1154 break;
1155 case ':':
1156 *q++ = pathSep;
1157 break;
1158 default:
1159 *q++ = *p;
1160 }
1161 }
1162 *q = '\0';
1163
1164 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched");
1165 return formatted_path;
1166 }
1167
1168
1169 bool os::set_boot_path(char fileSep, char pathSep) {
1170 const char* home = Arguments::get_java_home();
1171 int home_len = (int)strlen(home);
1172
1173 static const char* meta_index_dir_format = "%/lib/";
1174 static const char* meta_index_format = "%/lib/meta-index";
1175 char* meta_index = format_boot_path(meta_index_format, home, home_len, fileSep, pathSep);
1176 if (meta_index == NULL) return false;
1177 char* meta_index_dir = format_boot_path(meta_index_dir_format, home, home_len, fileSep, pathSep);
1178 if (meta_index_dir == NULL) return false;
1179 Arguments::set_meta_index_path(meta_index, meta_index_dir);
1180
1181 // Any modification to the JAR-file list, for the boot classpath must be
1182 // aligned with install/install/make/common/Pack.gmk. Note: boot class
1183 // path class JARs, are stripped for StackMapTable to reduce download size.
1184 static const char classpath_format[] =
1185 "%/lib/resources.jar:"
1186 "%/lib/rt.jar:"
1187 "%/lib/sunrsasign.jar:"
1188 "%/lib/jsse.jar:"
1189 "%/lib/jce.jar:"
1190 "%/lib/charsets.jar:"
1191 "%/lib/jfr.jar:"
1192 "%/classes";
1193 char* sysclasspath = format_boot_path(classpath_format, home, home_len, fileSep, pathSep);
1194 if (sysclasspath == NULL) return false;
1195 Arguments::set_sysclasspath(sysclasspath);
1196
1197 return true;
1198 }
1199
1200 /*
1201 * Splits a path, based on its separator, the number of
1202 * elements is returned back in n.
1203 * It is the callers responsibility to:
1204 * a> check the value of n, and n may be 0.
1205 * b> ignore any empty path elements
1206 * c> free up the data.
1207 */
1208 char** os::split_path(const char* path, int* n) {
1209 *n = 0;
1210 if (path == NULL || strlen(path) == 0) {
1211 return NULL;
1212 }
1213 const char psepchar = *os::path_separator();
1214 char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal);
1215 if (inpath == NULL) {
1216 return NULL;
1217 }
1218 strcpy(inpath, path);
1219 int count = 1;
1220 char* p = strchr(inpath, psepchar);
1221 // Get a count of elements to allocate memory
1222 while (p != NULL) {
1223 count++;
1224 p++;
1225 p = strchr(p, psepchar);
1226 }
1227 char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count, mtInternal);
1228 if (opath == NULL) {
1229 return NULL;
1230 }
1231
1232 // do the actual splitting
1233 p = inpath;
1234 for (int i = 0 ; i < count ; i++) {
1235 size_t len = strcspn(p, os::path_separator());
1236 if (len > JVM_MAXPATHLEN) {
1237 return NULL;
1238 }
1239 // allocate the string and add terminator storage
1240 char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
1241 if (s == NULL) {
1242 return NULL;
1243 }
1244 strncpy(s, p, len);
1245 s[len] = '\0';
1246 opath[i] = s;
1247 p += len + 1;
1248 }
1249 FREE_C_HEAP_ARRAY(char, inpath, mtInternal);
1250 *n = count;
1251 return opath;
1252 }
1253
1254 void os::set_memory_serialize_page(address page) {
1255 int count = log2_intptr(sizeof(class JavaThread)) - log2_intptr(64);
1256 _mem_serialize_page = (volatile int32_t *)page;
1257 // We initialize the serialization page shift count here
1258 // We assume a cache line size of 64 bytes
1259 assert(SerializePageShiftCount == count,
1260 "thread size changed, fix SerializePageShiftCount constant");
1261 set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t)));
1262 }
1263
1264 static volatile intptr_t SerializePageLock = 0;
1265
1266 // This method is called from signal handler when SIGSEGV occurs while the current
1267 // thread tries to store to the "read-only" memory serialize page during state
1268 // transition.
1269 void os::block_on_serialize_page_trap() {
1270 if (TraceSafepoint) {
1271 tty->print_cr("Block until the serialize page permission restored");
1272 }
1273 // When VMThread is holding the SerializePageLock during modifying the
1274 // access permission of the memory serialize page, the following call
1275 // will block until the permission of that page is restored to rw.
1276 // Generally, it is unsafe to manipulate locks in signal handlers, but in
1277 // this case, it's OK as the signal is synchronous and we know precisely when
1278 // it can occur.
1279 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page");
1280 Thread::muxRelease(&SerializePageLock);
1281 }
1282
1283 // Serialize all thread state variables
1284 void os::serialize_thread_states() {
1285 // On some platforms such as Solaris & Linux, the time duration of the page
1286 // permission restoration is observed to be much longer than expected due to
1287 // scheduler starvation problem etc. To avoid the long synchronization
1288 // time and expensive page trap spinning, 'SerializePageLock' is used to block
1289 // the mutator thread if such case is encountered. See bug 6546278 for details.
1290 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states");
1291 os::protect_memory((char *)os::get_memory_serialize_page(),
1292 os::vm_page_size(), MEM_PROT_READ);
1293 os::protect_memory((char *)os::get_memory_serialize_page(),
1294 os::vm_page_size(), MEM_PROT_RW);
1295 Thread::muxRelease(&SerializePageLock);
1296 }
1297
1298 // Returns true if the current stack pointer is above the stack shadow
1299 // pages, false otherwise.
1300
1301 bool os::stack_shadow_pages_available(Thread *thread, methodHandle method) {
1302 assert(StackRedPages > 0 && StackYellowPages > 0,"Sanity check");
1303 address sp = current_stack_pointer();
1304 // Check if we have StackShadowPages above the yellow zone. This parameter
1305 // is dependent on the depth of the maximum VM call stack possible from
1306 // the handler for stack overflow. 'instanceof' in the stack overflow
1307 // handler or a println uses at least 8k stack of VM and native code
1308 // respectively.
1309 const int framesize_in_bytes =
1310 Interpreter::size_top_interpreter_activation(method()) * wordSize;
1311 int reserved_area = ((StackShadowPages + StackRedPages + StackYellowPages)
1312 * vm_page_size()) + framesize_in_bytes;
1313 // The very lower end of the stack
1314 address stack_limit = thread->stack_base() - thread->stack_size();
1315 return (sp > (stack_limit + reserved_area));
1316 }
1317
1318 size_t os::page_size_for_region(size_t region_size, size_t min_pages) {
1319 assert(min_pages > 0, "sanity");
1320 if (UseLargePages) {
1321 const size_t max_page_size = region_size / min_pages;
1322
1323 for (size_t i = 0; _page_sizes[i] != 0; ++i) {
1324 const size_t page_size = _page_sizes[i];
1325 if (page_size <= max_page_size && is_size_aligned(region_size, page_size)) {
1326 return page_size;
1327 }
1328 }
1329 }
1330
1331 return vm_page_size();
1332 }
1333
1334 #ifndef PRODUCT
1335 void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count)
1336 {
1337 if (TracePageSizes) {
1338 tty->print("%s: ", str);
1339 for (int i = 0; i < count; ++i) {
1340 tty->print(" " SIZE_FORMAT, page_sizes[i]);
1341 }
1342 tty->cr();
1343 }
1344 }
1345
1346 void os::trace_page_sizes(const char* str, const size_t region_min_size,
1347 const size_t region_max_size, const size_t page_size,
1348 const char* base, const size_t size)
1349 {
1350 if (TracePageSizes) {
1351 tty->print_cr("%s: min=" SIZE_FORMAT " max=" SIZE_FORMAT
1352 " pg_sz=" SIZE_FORMAT " base=" PTR_FORMAT
1353 " size=" SIZE_FORMAT,
1354 str, region_min_size, region_max_size,
1355 page_size, base, size);
1356 }
1357 }
1358 #endif // #ifndef PRODUCT
1359
1360 // This is the working definition of a server class machine:
1361 // >= 2 physical CPU's and >=2GB of memory, with some fuzz
1362 // because the graphics memory (?) sometimes masks physical memory.
1363 // If you want to change the definition of a server class machine
1364 // on some OS or platform, e.g., >=4GB on Windohs platforms,
1365 // then you'll have to parameterize this method based on that state,
1366 // as was done for logical processors here, or replicate and
1367 // specialize this method for each platform. (Or fix os to have
1368 // some inheritance structure and use subclassing. Sigh.)
1369 // If you want some platform to always or never behave as a server
1370 // class machine, change the setting of AlwaysActAsServerClassMachine
1371 // and NeverActAsServerClassMachine in globals*.hpp.
1372 bool os::is_server_class_machine() {
1373 // First check for the early returns
1374 if (NeverActAsServerClassMachine) {
1375 return false;
1376 }
1377 if (AlwaysActAsServerClassMachine) {
1378 return true;
1379 }
1380 // Then actually look at the machine
1381 bool result = false;
1382 const unsigned int server_processors = 2;
1383 const julong server_memory = 2UL * G;
1384 // We seem not to get our full complement of memory.
1385 // We allow some part (1/8?) of the memory to be "missing",
1386 // based on the sizes of DIMMs, and maybe graphics cards.
1387 const julong missing_memory = 256UL * M;
1388
1389 /* Is this a server class machine? */
1390 if ((os::active_processor_count() >= (int)server_processors) &&
1391 (os::physical_memory() >= (server_memory - missing_memory))) {
1392 const unsigned int logical_processors =
1393 VM_Version::logical_processors_per_package();
1394 if (logical_processors > 1) {
1395 const unsigned int physical_packages =
1396 os::active_processor_count() / logical_processors;
1397 if (physical_packages > server_processors) {
1398 result = true;
1399 }
1400 } else {
1401 result = true;
1402 }
1403 }
1404 return result;
1405 }
1406
1407 void os::SuspendedThreadTask::run() {
1408 assert(Threads_lock->owned_by_self() || (_thread == VMThread::vm_thread()), "must have threads lock to call this");
1409 internal_do_task();
1410 _done = true;
1411 }
1412
1413 bool os::create_stack_guard_pages(char* addr, size_t bytes) {
1414 return os::pd_create_stack_guard_pages(addr, bytes);
1415 }
1416
1417 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint) {
1418 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1419 if (result != NULL) {
1420 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1421 }
1422
1423 return result;
1424 }
1425
1426 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint,
1427 MEMFLAGS flags) {
1428 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1429 if (result != NULL) {
1430 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1431 MemTracker::record_virtual_memory_type((address)result, flags);
1432 }
1433
1434 return result;
1435 }
1436
1437 char* os::attempt_reserve_memory_at(size_t bytes, char* addr) {
1438 char* result = pd_attempt_reserve_memory_at(bytes, addr);
1439 if (result != NULL) {
1440 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1441 }
1442 return result;
1443 }
1444
1445 void os::split_reserved_memory(char *base, size_t size,
1446 size_t split, bool realloc) {
1447 pd_split_reserved_memory(base, size, split, realloc);
1448 }
1449
1450 bool os::commit_memory(char* addr, size_t bytes, bool executable) {
1451 bool res = pd_commit_memory(addr, bytes, executable);
1452 if (res) {
1453 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1454 }
1455 return res;
1456 }
1457
1458 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint,
1459 bool executable) {
1460 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable);
1461 if (res) {
1462 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1463 }
1464 return res;
1465 }
1466
1467 void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable,
1468 const char* mesg) {
1469 pd_commit_memory_or_exit(addr, bytes, executable, mesg);
1470 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1471 }
1472
1473 void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint,
1474 bool executable, const char* mesg) {
1475 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg);
1476 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1477 }
1478
1479 bool os::uncommit_memory(char* addr, size_t bytes) {
1480 bool res;
1481 if (MemTracker::tracking_level() > NMT_minimal) {
1482 Tracker tkr = MemTracker::get_virtual_memory_uncommit_tracker();
1483 res = pd_uncommit_memory(addr, bytes);
1484 if (res) {
1485 tkr.record((address)addr, bytes);
1486 }
1487 } else {
1488 res = pd_uncommit_memory(addr, bytes);
1489 }
1490 return res;
1491 }
1492
1493 bool os::release_memory(char* addr, size_t bytes) {
1494 bool res;
1495 if (MemTracker::tracking_level() > NMT_minimal) {
1496 Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
1497 res = pd_release_memory(addr, bytes);
1498 if (res) {
1499 tkr.record((address)addr, bytes);
1500 }
1501 } else {
1502 res = pd_release_memory(addr, bytes);
1503 }
1504 return res;
1505 }
1506
1507 void os::pretouch_memory(char* start, char* end) {
1508 for (volatile char *p = start; p < end; p += os::vm_page_size()) {
1509 *p = 0;
1510 }
1511 }
1512
1513 char* os::map_memory(int fd, const char* file_name, size_t file_offset,
1514 char *addr, size_t bytes, bool read_only,
1515 bool allow_exec) {
1516 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec);
1517 if (result != NULL) {
1518 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC);
1519 }
1520 return result;
1521 }
1522
1523 char* os::remap_memory(int fd, const char* file_name, size_t file_offset,
1524 char *addr, size_t bytes, bool read_only,
1525 bool allow_exec) {
1526 return pd_remap_memory(fd, file_name, file_offset, addr, bytes,
1527 read_only, allow_exec);
1528 }
1529
1530 bool os::unmap_memory(char *addr, size_t bytes) {
1531 bool result;
1532 if (MemTracker::tracking_level() > NMT_minimal) {
1533 Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
1534 result = pd_unmap_memory(addr, bytes);
1535 if (result) {
1536 tkr.record((address)addr, bytes);
1537 }
1538 } else {
1539 result = pd_unmap_memory(addr, bytes);
1540 }
1541 return result;
1542 }
1543
1544 void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) {
1545 pd_free_memory(addr, bytes, alignment_hint);
1546 }
1547
1548 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
1549 pd_realign_memory(addr, bytes, alignment_hint);
1550 }
1551
1552 #ifndef TARGET_OS_FAMILY_windows
1553 /* try to switch state from state "from" to state "to"
1554 * returns the state set after the method is complete
1555 */
1556 os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from,
1557 os::SuspendResume::State to)
1558 {
1559 os::SuspendResume::State result =
1560 (os::SuspendResume::State) Atomic::cmpxchg((jint) to, (jint *) &_state, (jint) from);
1561 if (result == from) {
1562 // success
1563 return to;
1564 }
1565 return result;
1566 }
1567 #endif
1568
1569 /////////////// Unit tests ///////////////
1570
1571 #ifndef PRODUCT
1572
1573 #define assert_eq(a,b) assert(a == b, err_msg(SIZE_FORMAT " != " SIZE_FORMAT, a, b))
1574
1575 class TestOS : AllStatic {
1576 static size_t small_page_size() {
1577 return os::vm_page_size();
1578 }
1579
1580 static size_t large_page_size() {
1581 const size_t large_page_size_example = 4 * M;
1582 return os::page_size_for_region(large_page_size_example, 1);
1583 }
1584
1585 static void test_page_size_for_region() {
1586 if (UseLargePages) {
1587 const size_t small_page = small_page_size();
1588 const size_t large_page = large_page_size();
1589
1590 if (large_page > small_page) {
1591 size_t num_small_pages_in_large = large_page / small_page;
1592 size_t page = os::page_size_for_region(large_page, num_small_pages_in_large);
1593
1594 assert_eq(page, small_page);
1595 }
1596 }
1597 }
1598
1599 static void test_page_size_for_region_alignment() {
1600 if (UseLargePages) {
1601 const size_t small_page = small_page_size();
1602 const size_t large_page = large_page_size();
1603 if (large_page > small_page) {
1604 const size_t unaligned_region = large_page + 17;
1605 size_t page = os::page_size_for_region(unaligned_region, 1);
1606 assert_eq(page, small_page);
1607
1608 const size_t num_pages = 5;
1609 const size_t aligned_region = large_page * num_pages;
1610 page = os::page_size_for_region(aligned_region, num_pages);
1611 assert_eq(page, large_page);
1612 }
1613 }
1614 }
1615
1616 public:
1617 static void run_tests() {
1618 test_page_size_for_region();
1619 test_page_size_for_region_alignment();
1620 }
1621 };
1622
1623 void TestOS_test() {
1624 TestOS::run_tests();
1625 }
1626
1627 #endif // PRODUCT