1 /*
2 * Copyright (c) 1997, 2017, 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/moduleEntry.hpp"
29 #include "classfile/systemDictionary.hpp"
30 #include "classfile/vmSymbols.hpp"
31 #include "code/codeCache.hpp"
32 #include "code/icBuffer.hpp"
33 #include "code/vtableStubs.hpp"
34 #include "gc/shared/vmGCOperations.hpp"
35 #include "interpreter/interpreter.hpp"
36 #include "logging/log.hpp"
37 #include "logging/logStream.inline.hpp"
38 #include "memory/allocation.inline.hpp"
39 #ifdef ASSERT
40 #include "memory/guardedMemory.hpp"
41 #endif
42 #include "memory/resourceArea.hpp"
43 #include "oops/oop.inline.hpp"
44 #include "prims/jvm.h"
45 #include "prims/jvm_misc.hpp"
46 #include "prims/privilegedStack.hpp"
47 #include "runtime/arguments.hpp"
48 #include "runtime/atomic.hpp"
49 #include "runtime/frame.inline.hpp"
50 #include "runtime/interfaceSupport.hpp"
51 #include "runtime/java.hpp"
52 #include "runtime/javaCalls.hpp"
53 #include "runtime/mutexLocker.hpp"
54 #include "runtime/os.inline.hpp"
55 #include "runtime/stubRoutines.hpp"
56 #include "runtime/thread.inline.hpp"
57 #include "runtime/vm_version.hpp"
58 #include "services/attachListener.hpp"
59 #include "services/mallocTracker.hpp"
60 #include "services/memTracker.hpp"
61 #include "services/nmtCommon.hpp"
62 #include "services/threadService.hpp"
63 #include "utilities/defaultStream.hpp"
64 #include "utilities/events.hpp"
65
66 # include <signal.h>
67 # include <errno.h>
68
69 OSThread* os::_starting_thread = NULL;
70 address os::_polling_page = NULL;
71 volatile int32_t* os::_mem_serialize_page = NULL;
72 uintptr_t os::_serialize_page_mask = 0;
73 long os::_rand_seed = 1;
74 int os::_processor_count = 0;
75 int os::_initial_active_processor_count = 0;
76 size_t os::_page_sizes[os::page_sizes_max];
77
78 #ifndef PRODUCT
79 julong os::num_mallocs = 0; // # of calls to malloc/realloc
80 julong os::alloc_bytes = 0; // # of bytes allocated
81 julong os::num_frees = 0; // # of calls to free
82 julong os::free_bytes = 0; // # of bytes freed
83 #endif
84
85 static juint cur_malloc_words = 0; // current size for MallocMaxTestWords
86
87 void os_init_globals() {
88 // Called from init_globals().
89 // See Threads::create_vm() in thread.cpp, and init.cpp.
90 os::init_globals();
91 }
92
93 // Fill in buffer with current local time as an ISO-8601 string.
94 // E.g., yyyy-mm-ddThh:mm:ss-zzzz.
95 // Returns buffer, or NULL if it failed.
96 // This would mostly be a call to
97 // strftime(...., "%Y-%m-%d" "T" "%H:%M:%S" "%z", ....)
98 // except that on Windows the %z behaves badly, so we do it ourselves.
99 // Also, people wanted milliseconds on there,
100 // and strftime doesn't do milliseconds.
101 char* os::iso8601_time(char* buffer, size_t buffer_length, bool utc) {
102 // Output will be of the form "YYYY-MM-DDThh:mm:ss.mmm+zzzz\0"
103 // 1 2
104 // 12345678901234567890123456789
105 // format string: "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d"
106 static const size_t needed_buffer = 29;
107
108 // Sanity check the arguments
109 if (buffer == NULL) {
110 assert(false, "NULL buffer");
111 return NULL;
112 }
113 if (buffer_length < needed_buffer) {
114 assert(false, "buffer_length too small");
115 return NULL;
116 }
117 // Get the current time
118 jlong milliseconds_since_19700101 = javaTimeMillis();
119 const int milliseconds_per_microsecond = 1000;
120 const time_t seconds_since_19700101 =
121 milliseconds_since_19700101 / milliseconds_per_microsecond;
122 const int milliseconds_after_second =
123 milliseconds_since_19700101 % milliseconds_per_microsecond;
124 // Convert the time value to a tm and timezone variable
125 struct tm time_struct;
126 if (utc) {
127 if (gmtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
128 assert(false, "Failed gmtime_pd");
129 return NULL;
130 }
131 } else {
132 if (localtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
133 assert(false, "Failed localtime_pd");
134 return NULL;
135 }
136 }
137 #if defined(_ALLBSD_SOURCE)
138 const time_t zone = (time_t) time_struct.tm_gmtoff;
139 #else
140 const time_t zone = timezone;
141 #endif
142
143 // If daylight savings time is in effect,
144 // we are 1 hour East of our time zone
145 const time_t seconds_per_minute = 60;
146 const time_t minutes_per_hour = 60;
147 const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour;
148 time_t UTC_to_local = zone;
149 if (time_struct.tm_isdst > 0) {
150 UTC_to_local = UTC_to_local - seconds_per_hour;
151 }
152
153 // No offset when dealing with UTC
154 if (utc) {
155 UTC_to_local = 0;
156 }
157
158 // Compute the time zone offset.
159 // localtime_pd() sets timezone to the difference (in seconds)
160 // between UTC and and local time.
161 // ISO 8601 says we need the difference between local time and UTC,
162 // we change the sign of the localtime_pd() result.
163 const time_t local_to_UTC = -(UTC_to_local);
164 // Then we have to figure out if if we are ahead (+) or behind (-) UTC.
165 char sign_local_to_UTC = '+';
166 time_t abs_local_to_UTC = local_to_UTC;
167 if (local_to_UTC < 0) {
168 sign_local_to_UTC = '-';
169 abs_local_to_UTC = -(abs_local_to_UTC);
170 }
171 // Convert time zone offset seconds to hours and minutes.
172 const time_t zone_hours = (abs_local_to_UTC / seconds_per_hour);
173 const time_t zone_min =
174 ((abs_local_to_UTC % seconds_per_hour) / seconds_per_minute);
175
176 // Print an ISO 8601 date and time stamp into the buffer
177 const int year = 1900 + time_struct.tm_year;
178 const int month = 1 + time_struct.tm_mon;
179 const int printed = jio_snprintf(buffer, buffer_length,
180 "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d",
181 year,
182 month,
183 time_struct.tm_mday,
184 time_struct.tm_hour,
185 time_struct.tm_min,
186 time_struct.tm_sec,
187 milliseconds_after_second,
188 sign_local_to_UTC,
189 zone_hours,
190 zone_min);
191 if (printed == 0) {
192 assert(false, "Failed jio_printf");
193 return NULL;
194 }
195 return buffer;
196 }
197
198 OSReturn os::set_priority(Thread* thread, ThreadPriority p) {
199 #ifdef ASSERT
200 if (!(!thread->is_Java_thread() ||
201 Thread::current() == thread ||
202 Threads_lock->owned_by_self()
203 || thread->is_Compiler_thread()
204 )) {
205 assert(false, "possibility of dangling Thread pointer");
206 }
207 #endif
208
209 if (p >= MinPriority && p <= MaxPriority) {
210 int priority = java_to_os_priority[p];
211 return set_native_priority(thread, priority);
212 } else {
213 assert(false, "Should not happen");
214 return OS_ERR;
215 }
216 }
217
218 // The mapping from OS priority back to Java priority may be inexact because
219 // Java priorities can map M:1 with native priorities. If you want the definite
220 // Java priority then use JavaThread::java_priority()
221 OSReturn os::get_priority(const Thread* const thread, ThreadPriority& priority) {
222 int p;
223 int os_prio;
224 OSReturn ret = get_native_priority(thread, &os_prio);
225 if (ret != OS_OK) return ret;
226
227 if (java_to_os_priority[MaxPriority] > java_to_os_priority[MinPriority]) {
228 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] > os_prio; p--) ;
229 } else {
230 // niceness values are in reverse order
231 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] < os_prio; p--) ;
232 }
233 priority = (ThreadPriority)p;
234 return OS_OK;
235 }
236
237
238 // --------------------- sun.misc.Signal (optional) ---------------------
239
240
241 // SIGBREAK is sent by the keyboard to query the VM state
242 #ifndef SIGBREAK
243 #define SIGBREAK SIGQUIT
244 #endif
245
246 // sigexitnum_pd is a platform-specific special signal used for terminating the Signal thread.
247
248
249 static void signal_thread_entry(JavaThread* thread, TRAPS) {
250 os::set_priority(thread, NearMaxPriority);
251 while (true) {
252 int sig;
253 {
254 // FIXME : Currently we have not decided what should be the status
255 // for this java thread blocked here. Once we decide about
256 // that we should fix this.
257 sig = os::signal_wait();
258 }
259 if (sig == os::sigexitnum_pd()) {
260 // Terminate the signal thread
261 return;
262 }
263
264 switch (sig) {
265 case SIGBREAK: {
266 // Check if the signal is a trigger to start the Attach Listener - in that
267 // case don't print stack traces.
268 if (!DisableAttachMechanism && AttachListener::is_init_trigger()) {
269 continue;
270 }
271 // Print stack traces
272 // Any SIGBREAK operations added here should make sure to flush
273 // the output stream (e.g. tty->flush()) after output. See 4803766.
274 // Each module also prints an extra carriage return after its output.
275 VM_PrintThreads op;
276 VMThread::execute(&op);
277 VM_PrintJNI jni_op;
278 VMThread::execute(&jni_op);
279 VM_FindDeadlocks op1(tty);
280 VMThread::execute(&op1);
281 Universe::print_heap_at_SIGBREAK();
282 if (PrintClassHistogram) {
283 VM_GC_HeapInspection op1(tty, true /* force full GC before heap inspection */);
284 VMThread::execute(&op1);
285 }
286 if (JvmtiExport::should_post_data_dump()) {
287 JvmtiExport::post_data_dump();
288 }
289 break;
290 }
291 default: {
292 // Dispatch the signal to java
293 HandleMark hm(THREAD);
294 Klass* k = SystemDictionary::resolve_or_null(vmSymbols::jdk_internal_misc_Signal(), THREAD);
295 KlassHandle klass (THREAD, k);
296 if (klass.not_null()) {
297 JavaValue result(T_VOID);
298 JavaCallArguments args;
299 args.push_int(sig);
300 JavaCalls::call_static(
301 &result,
302 klass,
303 vmSymbols::dispatch_name(),
304 vmSymbols::int_void_signature(),
305 &args,
306 THREAD
307 );
308 }
309 if (HAS_PENDING_EXCEPTION) {
310 // tty is initialized early so we don't expect it to be null, but
311 // if it is we can't risk doing an initialization that might
312 // trigger additional out-of-memory conditions
313 if (tty != NULL) {
314 char klass_name[256];
315 char tmp_sig_name[16];
316 const char* sig_name = "UNKNOWN";
317 InstanceKlass::cast(PENDING_EXCEPTION->klass())->
318 name()->as_klass_external_name(klass_name, 256);
319 if (os::exception_name(sig, tmp_sig_name, 16) != NULL)
320 sig_name = tmp_sig_name;
321 warning("Exception %s occurred dispatching signal %s to handler"
322 "- the VM may need to be forcibly terminated",
323 klass_name, sig_name );
324 }
325 CLEAR_PENDING_EXCEPTION;
326 }
327 }
328 }
329 }
330 }
331
332 void os::init_before_ergo() {
333 initialize_initial_active_processor_count();
334 // We need to initialize large page support here because ergonomics takes some
335 // decisions depending on large page support and the calculated large page size.
336 large_page_init();
337
338 // We need to adapt the configured number of stack protection pages given
339 // in 4K pages to the actual os page size. We must do this before setting
340 // up minimal stack sizes etc. in os::init_2().
341 JavaThread::set_stack_red_zone_size (align_size_up(StackRedPages * 4 * K, vm_page_size()));
342 JavaThread::set_stack_yellow_zone_size (align_size_up(StackYellowPages * 4 * K, vm_page_size()));
343 JavaThread::set_stack_reserved_zone_size(align_size_up(StackReservedPages * 4 * K, vm_page_size()));
344 JavaThread::set_stack_shadow_zone_size (align_size_up(StackShadowPages * 4 * K, vm_page_size()));
345
346 // VM version initialization identifies some characteristics of the
347 // platform that are used during ergonomic decisions.
348 VM_Version::init_before_ergo();
349 }
350
351 void os::signal_init(TRAPS) {
352 if (!ReduceSignalUsage) {
353 // Setup JavaThread for processing signals
354 Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(), true, CHECK);
355 instanceKlassHandle klass (THREAD, k);
356 instanceHandle thread_oop = klass->allocate_instance_handle(CHECK);
357
358 const char thread_name[] = "Signal Dispatcher";
359 Handle string = java_lang_String::create_from_str(thread_name, CHECK);
360
361 // Initialize thread_oop to put it into the system threadGroup
362 Handle thread_group (THREAD, Universe::system_thread_group());
363 JavaValue result(T_VOID);
364 JavaCalls::call_special(&result, thread_oop,
365 klass,
366 vmSymbols::object_initializer_name(),
367 vmSymbols::threadgroup_string_void_signature(),
368 thread_group,
369 string,
370 CHECK);
371
372 KlassHandle group(THREAD, SystemDictionary::ThreadGroup_klass());
373 JavaCalls::call_special(&result,
374 thread_group,
375 group,
376 vmSymbols::add_method_name(),
377 vmSymbols::thread_void_signature(),
378 thread_oop, // ARG 1
379 CHECK);
380
381 os::signal_init_pd();
382
383 { MutexLocker mu(Threads_lock);
384 JavaThread* signal_thread = new JavaThread(&signal_thread_entry);
385
386 // At this point it may be possible that no osthread was created for the
387 // JavaThread due to lack of memory. We would have to throw an exception
388 // in that case. However, since this must work and we do not allow
389 // exceptions anyway, check and abort if this fails.
390 if (signal_thread == NULL || signal_thread->osthread() == NULL) {
391 vm_exit_during_initialization("java.lang.OutOfMemoryError",
392 os::native_thread_creation_failed_msg());
393 }
394
395 java_lang_Thread::set_thread(thread_oop(), signal_thread);
396 java_lang_Thread::set_priority(thread_oop(), NearMaxPriority);
397 java_lang_Thread::set_daemon(thread_oop());
398
399 signal_thread->set_threadObj(thread_oop());
400 Threads::add(signal_thread);
401 Thread::start(signal_thread);
402 }
403 // Handle ^BREAK
404 os::signal(SIGBREAK, os::user_handler());
405 }
406 }
407
408
409 void os::terminate_signal_thread() {
410 if (!ReduceSignalUsage)
411 signal_notify(sigexitnum_pd());
412 }
413
414
415 // --------------------- loading libraries ---------------------
416
417 typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *);
418 extern struct JavaVM_ main_vm;
419
420 static void* _native_java_library = NULL;
421
422 void* os::native_java_library() {
423 if (_native_java_library == NULL) {
424 char buffer[JVM_MAXPATHLEN];
425 char ebuf[1024];
426
427 // Try to load verify dll first. In 1.3 java dll depends on it and is not
428 // always able to find it when the loading executable is outside the JDK.
429 // In order to keep working with 1.2 we ignore any loading errors.
430 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
431 "verify")) {
432 dll_load(buffer, ebuf, sizeof(ebuf));
433 }
434
435 // Load java dll
436 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
437 "java")) {
438 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf));
439 }
440 if (_native_java_library == NULL) {
441 vm_exit_during_initialization("Unable to load native library", ebuf);
442 }
443
444 #if defined(__OpenBSD__)
445 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so
446 // ignore errors
447 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
448 "net")) {
449 dll_load(buffer, ebuf, sizeof(ebuf));
450 }
451 #endif
452 }
453 return _native_java_library;
454 }
455
456 /*
457 * Support for finding Agent_On(Un)Load/Attach<_lib_name> if it exists.
458 * If check_lib == true then we are looking for an
459 * Agent_OnLoad_lib_name or Agent_OnAttach_lib_name function to determine if
460 * this library is statically linked into the image.
461 * If check_lib == false then we will look for the appropriate symbol in the
462 * executable if agent_lib->is_static_lib() == true or in the shared library
463 * referenced by 'handle'.
464 */
465 void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib,
466 const char *syms[], size_t syms_len) {
467 assert(agent_lib != NULL, "sanity check");
468 const char *lib_name;
469 void *handle = agent_lib->os_lib();
470 void *entryName = NULL;
471 char *agent_function_name;
472 size_t i;
473
474 // If checking then use the agent name otherwise test is_static_lib() to
475 // see how to process this lookup
476 lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL);
477 for (i = 0; i < syms_len; i++) {
478 agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path());
479 if (agent_function_name == NULL) {
480 break;
481 }
482 entryName = dll_lookup(handle, agent_function_name);
483 FREE_C_HEAP_ARRAY(char, agent_function_name);
484 if (entryName != NULL) {
485 break;
486 }
487 }
488 return entryName;
489 }
490
491 // See if the passed in agent is statically linked into the VM image.
492 bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
493 size_t syms_len) {
494 void *ret;
495 void *proc_handle;
496 void *save_handle;
497
498 assert(agent_lib != NULL, "sanity check");
499 if (agent_lib->name() == NULL) {
500 return false;
501 }
502 proc_handle = get_default_process_handle();
503 // Check for Agent_OnLoad/Attach_lib_name function
504 save_handle = agent_lib->os_lib();
505 // We want to look in this process' symbol table.
506 agent_lib->set_os_lib(proc_handle);
507 ret = find_agent_function(agent_lib, true, syms, syms_len);
508 if (ret != NULL) {
509 // Found an entry point like Agent_OnLoad_lib_name so we have a static agent
510 agent_lib->set_valid();
511 agent_lib->set_static_lib(true);
512 return true;
513 }
514 agent_lib->set_os_lib(save_handle);
515 return false;
516 }
517
518 // --------------------- heap allocation utilities ---------------------
519
520 char *os::strdup(const char *str, MEMFLAGS flags) {
521 size_t size = strlen(str);
522 char *dup_str = (char *)malloc(size + 1, flags);
523 if (dup_str == NULL) return NULL;
524 strcpy(dup_str, str);
525 return dup_str;
526 }
527
528 char* os::strdup_check_oom(const char* str, MEMFLAGS flags) {
529 char* p = os::strdup(str, flags);
530 if (p == NULL) {
531 vm_exit_out_of_memory(strlen(str) + 1, OOM_MALLOC_ERROR, "os::strdup_check_oom");
532 }
533 return p;
534 }
535
536
537 #define paranoid 0 /* only set to 1 if you suspect checking code has bug */
538
539 #ifdef ASSERT
540
541 static void verify_memory(void* ptr) {
542 GuardedMemory guarded(ptr);
543 if (!guarded.verify_guards()) {
544 tty->print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees);
545 tty->print_cr("## memory stomp:");
546 guarded.print_on(tty);
547 fatal("memory stomping error");
548 }
549 }
550
551 #endif
552
553 //
554 // This function supports testing of the malloc out of memory
555 // condition without really running the system out of memory.
556 //
557 static bool has_reached_max_malloc_test_peak(size_t alloc_size) {
558 if (MallocMaxTestWords > 0) {
559 jint words = (jint)(alloc_size / BytesPerWord);
560
561 if ((cur_malloc_words + words) > MallocMaxTestWords) {
562 return true;
563 }
564 Atomic::add(words, (volatile jint *)&cur_malloc_words);
565 }
566 return false;
567 }
568
569 void* os::malloc(size_t size, MEMFLAGS flags) {
570 return os::malloc(size, flags, CALLER_PC);
571 }
572
573 void* os::malloc(size_t size, MEMFLAGS memflags, const NativeCallStack& stack) {
574 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
575 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
576
577 #ifdef ASSERT
578 // checking for the WatcherThread and crash_protection first
579 // since os::malloc can be called when the libjvm.{dll,so} is
580 // first loaded and we don't have a thread yet.
581 // try to find the thread after we see that the watcher thread
582 // exists and has crash protection.
583 WatcherThread *wt = WatcherThread::watcher_thread();
584 if (wt != NULL && wt->has_crash_protection()) {
585 Thread* thread = Thread::current_or_null();
586 if (thread == wt) {
587 assert(!wt->has_crash_protection(),
588 "Can't malloc with crash protection from WatcherThread");
589 }
590 }
591 #endif
592
593 if (size == 0) {
594 // return a valid pointer if size is zero
595 // if NULL is returned the calling functions assume out of memory.
596 size = 1;
597 }
598
599 // NMT support
600 NMT_TrackingLevel level = MemTracker::tracking_level();
601 size_t nmt_header_size = MemTracker::malloc_header_size(level);
602
603 #ifndef ASSERT
604 const size_t alloc_size = size + nmt_header_size;
605 #else
606 const size_t alloc_size = GuardedMemory::get_total_size(size + nmt_header_size);
607 if (size + nmt_header_size > alloc_size) { // Check for rollover.
608 return NULL;
609 }
610 #endif
611
612 // For the test flag -XX:MallocMaxTestWords
613 if (has_reached_max_malloc_test_peak(size)) {
614 return NULL;
615 }
616
617 u_char* ptr;
618 ptr = (u_char*)::malloc(alloc_size);
619
620 #ifdef ASSERT
621 if (ptr == NULL) {
622 return NULL;
623 }
624 // Wrap memory with guard
625 GuardedMemory guarded(ptr, size + nmt_header_size);
626 ptr = guarded.get_user_ptr();
627 #endif
628 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) {
629 tty->print_cr("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr));
630 breakpoint();
631 }
632 debug_only(if (paranoid) verify_memory(ptr));
633 if (PrintMalloc && tty != NULL) {
634 tty->print_cr("os::malloc " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr));
635 }
636
637 // we do not track guard memory
638 return MemTracker::record_malloc((address)ptr, size, memflags, stack, level);
639 }
640
641 void* os::realloc(void *memblock, size_t size, MEMFLAGS flags) {
642 return os::realloc(memblock, size, flags, CALLER_PC);
643 }
644
645 void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, const NativeCallStack& stack) {
646
647 // For the test flag -XX:MallocMaxTestWords
648 if (has_reached_max_malloc_test_peak(size)) {
649 return NULL;
650 }
651
652 if (size == 0) {
653 // return a valid pointer if size is zero
654 // if NULL is returned the calling functions assume out of memory.
655 size = 1;
656 }
657
658 #ifndef ASSERT
659 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
660 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
661 // NMT support
662 void* membase = MemTracker::record_free(memblock);
663 NMT_TrackingLevel level = MemTracker::tracking_level();
664 size_t nmt_header_size = MemTracker::malloc_header_size(level);
665 void* ptr = ::realloc(membase, size + nmt_header_size);
666 return MemTracker::record_malloc(ptr, size, memflags, stack, level);
667 #else
668 if (memblock == NULL) {
669 return os::malloc(size, memflags, stack);
670 }
671 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
672 tty->print_cr("os::realloc caught " PTR_FORMAT, p2i(memblock));
673 breakpoint();
674 }
675 // NMT support
676 void* membase = MemTracker::malloc_base(memblock);
677 verify_memory(membase);
678 // always move the block
679 void* ptr = os::malloc(size, memflags, stack);
680 if (PrintMalloc && tty != NULL) {
681 tty->print_cr("os::realloc " SIZE_FORMAT " bytes, " PTR_FORMAT " --> " PTR_FORMAT, size, p2i(memblock), p2i(ptr));
682 }
683 // Copy to new memory if malloc didn't fail
684 if ( ptr != NULL ) {
685 GuardedMemory guarded(MemTracker::malloc_base(memblock));
686 // Guard's user data contains NMT header
687 size_t memblock_size = guarded.get_user_size() - MemTracker::malloc_header_size(memblock);
688 memcpy(ptr, memblock, MIN2(size, memblock_size));
689 if (paranoid) verify_memory(MemTracker::malloc_base(ptr));
690 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) {
691 tty->print_cr("os::realloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr));
692 breakpoint();
693 }
694 os::free(memblock);
695 }
696 return ptr;
697 #endif
698 }
699
700
701 void os::free(void *memblock) {
702 NOT_PRODUCT(inc_stat_counter(&num_frees, 1));
703 #ifdef ASSERT
704 if (memblock == NULL) return;
705 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
706 if (tty != NULL) tty->print_cr("os::free caught " PTR_FORMAT, p2i(memblock));
707 breakpoint();
708 }
709 void* membase = MemTracker::record_free(memblock);
710 verify_memory(membase);
711
712 GuardedMemory guarded(membase);
713 size_t size = guarded.get_user_size();
714 inc_stat_counter(&free_bytes, size);
715 membase = guarded.release_for_freeing();
716 if (PrintMalloc && tty != NULL) {
717 fprintf(stderr, "os::free " SIZE_FORMAT " bytes --> " PTR_FORMAT "\n", size, (uintptr_t)membase);
718 }
719 ::free(membase);
720 #else
721 void* membase = MemTracker::record_free(memblock);
722 ::free(membase);
723 #endif
724 }
725
726 void os::init_random(long initval) {
727 _rand_seed = initval;
728 }
729
730
731 long os::random() {
732 /* standard, well-known linear congruential random generator with
733 * next_rand = (16807*seed) mod (2**31-1)
734 * see
735 * (1) "Random Number Generators: Good Ones Are Hard to Find",
736 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988),
737 * (2) "Two Fast Implementations of the 'Minimal Standard' Random
738 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88.
739 */
740 const long a = 16807;
741 const unsigned long m = 2147483647;
742 const long q = m / a; assert(q == 127773, "weird math");
743 const long r = m % a; assert(r == 2836, "weird math");
744
745 // compute az=2^31p+q
746 unsigned long lo = a * (long)(_rand_seed & 0xFFFF);
747 unsigned long hi = a * (long)((unsigned long)_rand_seed >> 16);
748 lo += (hi & 0x7FFF) << 16;
749
750 // if q overflowed, ignore the overflow and increment q
751 if (lo > m) {
752 lo &= m;
753 ++lo;
754 }
755 lo += hi >> 15;
756
757 // if (p+q) overflowed, ignore the overflow and increment (p+q)
758 if (lo > m) {
759 lo &= m;
760 ++lo;
761 }
762 return (_rand_seed = lo);
763 }
764
765 // The INITIALIZED state is distinguished from the SUSPENDED state because the
766 // conditions in which a thread is first started are different from those in which
767 // a suspension is resumed. These differences make it hard for us to apply the
768 // tougher checks when starting threads that we want to do when resuming them.
769 // However, when start_thread is called as a result of Thread.start, on a Java
770 // thread, the operation is synchronized on the Java Thread object. So there
771 // cannot be a race to start the thread and hence for the thread to exit while
772 // we are working on it. Non-Java threads that start Java threads either have
773 // to do so in a context in which races are impossible, or should do appropriate
774 // locking.
775
776 void os::start_thread(Thread* thread) {
777 // guard suspend/resume
778 MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag);
779 OSThread* osthread = thread->osthread();
780 osthread->set_state(RUNNABLE);
781 pd_start_thread(thread);
782 }
783
784 void os::abort(bool dump_core) {
785 abort(dump_core && CreateCoredumpOnCrash, NULL, NULL);
786 }
787
788 //---------------------------------------------------------------------------
789 // Helper functions for fatal error handler
790
791 void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) {
792 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking");
793
794 int cols = 0;
795 int cols_per_line = 0;
796 switch (unitsize) {
797 case 1: cols_per_line = 16; break;
798 case 2: cols_per_line = 8; break;
799 case 4: cols_per_line = 4; break;
800 case 8: cols_per_line = 2; break;
801 default: return;
802 }
803
804 address p = start;
805 st->print(PTR_FORMAT ": ", p2i(start));
806 while (p < end) {
807 switch (unitsize) {
808 case 1: st->print("%02x", *(u1*)p); break;
809 case 2: st->print("%04x", *(u2*)p); break;
810 case 4: st->print("%08x", *(u4*)p); break;
811 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break;
812 }
813 p += unitsize;
814 cols++;
815 if (cols >= cols_per_line && p < end) {
816 cols = 0;
817 st->cr();
818 st->print(PTR_FORMAT ": ", p2i(p));
819 } else {
820 st->print(" ");
821 }
822 }
823 st->cr();
824 }
825
826 void os::print_environment_variables(outputStream* st, const char** env_list) {
827 if (env_list) {
828 st->print_cr("Environment Variables:");
829
830 for (int i = 0; env_list[i] != NULL; i++) {
831 char *envvar = ::getenv(env_list[i]);
832 if (envvar != NULL) {
833 st->print("%s", env_list[i]);
834 st->print("=");
835 st->print_cr("%s", envvar);
836 }
837 }
838 }
839 }
840
841 void os::print_cpu_info(outputStream* st, char* buf, size_t buflen) {
842 // cpu
843 st->print("CPU:");
844 st->print("total %d", os::processor_count());
845 // It's not safe to query number of active processors after crash
846 // st->print("(active %d)", os::active_processor_count()); but we can
847 // print the initial number of active processors.
848 // We access the raw value here because the assert in the accessor will
849 // fail if the crash occurs before initialization of this value.
850 st->print(" (initial active %d)", _initial_active_processor_count);
851 st->print(" %s", VM_Version::features_string());
852 st->cr();
853 pd_print_cpu_info(st, buf, buflen);
854 }
855
856 // Print a one line string summarizing the cpu, number of cores, memory, and operating system version
857 void os::print_summary_info(outputStream* st, char* buf, size_t buflen) {
858 st->print("Host: ");
859 #ifndef PRODUCT
860 if (get_host_name(buf, buflen)) {
861 st->print("%s, ", buf);
862 }
863 #endif // PRODUCT
864 get_summary_cpu_info(buf, buflen);
865 st->print("%s, ", buf);
866 size_t mem = physical_memory()/G;
867 if (mem == 0) { // for low memory systems
868 mem = physical_memory()/M;
869 st->print("%d cores, " SIZE_FORMAT "M, ", processor_count(), mem);
870 } else {
871 st->print("%d cores, " SIZE_FORMAT "G, ", processor_count(), mem);
872 }
873 get_summary_os_info(buf, buflen);
874 st->print_raw(buf);
875 st->cr();
876 }
877
878 void os::print_date_and_time(outputStream *st, char* buf, size_t buflen) {
879 const int secs_per_day = 86400;
880 const int secs_per_hour = 3600;
881 const int secs_per_min = 60;
882
883 time_t tloc;
884 (void)time(&tloc);
885 char* timestring = ctime(&tloc); // ctime adds newline.
886 // edit out the newline
887 char* nl = strchr(timestring, '\n');
888 if (nl != NULL) {
889 *nl = '\0';
890 }
891
892 struct tm tz;
893 if (localtime_pd(&tloc, &tz) != NULL) {
894 ::strftime(buf, buflen, "%Z", &tz);
895 st->print("Time: %s %s", timestring, buf);
896 } else {
897 st->print("Time: %s", timestring);
898 }
899
900 double t = os::elapsedTime();
901 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in
902 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int
903 // before printf. We lost some precision, but who cares?
904 int eltime = (int)t; // elapsed time in seconds
905
906 // print elapsed time in a human-readable format:
907 int eldays = eltime / secs_per_day;
908 int day_secs = eldays * secs_per_day;
909 int elhours = (eltime - day_secs) / secs_per_hour;
910 int hour_secs = elhours * secs_per_hour;
911 int elmins = (eltime - day_secs - hour_secs) / secs_per_min;
912 int minute_secs = elmins * secs_per_min;
913 int elsecs = (eltime - day_secs - hour_secs - minute_secs);
914 st->print_cr(" elapsed time: %d seconds (%dd %dh %dm %ds)", eltime, eldays, elhours, elmins, elsecs);
915 }
916
917 // moved from debug.cpp (used to be find()) but still called from there
918 // The verbose parameter is only set by the debug code in one case
919 void os::print_location(outputStream* st, intptr_t x, bool verbose) {
920 address addr = (address)x;
921 CodeBlob* b = CodeCache::find_blob_unsafe(addr);
922 if (b != NULL) {
923 if (b->is_buffer_blob()) {
924 // the interpreter is generated into a buffer blob
925 InterpreterCodelet* i = Interpreter::codelet_containing(addr);
926 if (i != NULL) {
927 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an Interpreter codelet", p2i(addr), (int)(addr - i->code_begin()));
928 i->print_on(st);
929 return;
930 }
931 if (Interpreter::contains(addr)) {
932 st->print_cr(INTPTR_FORMAT " is pointing into interpreter code"
933 " (not bytecode specific)", p2i(addr));
934 return;
935 }
936 //
937 if (AdapterHandlerLibrary::contains(b)) {
938 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an AdapterHandler", p2i(addr), (int)(addr - b->code_begin()));
939 AdapterHandlerLibrary::print_handler_on(st, b);
940 }
941 // the stubroutines are generated into a buffer blob
942 StubCodeDesc* d = StubCodeDesc::desc_for(addr);
943 if (d != NULL) {
944 st->print_cr(INTPTR_FORMAT " is at begin+%d in a stub", p2i(addr), (int)(addr - d->begin()));
945 d->print_on(st);
946 st->cr();
947 return;
948 }
949 if (StubRoutines::contains(addr)) {
950 st->print_cr(INTPTR_FORMAT " is pointing to an (unnamed) stub routine", p2i(addr));
951 return;
952 }
953 // the InlineCacheBuffer is using stubs generated into a buffer blob
954 if (InlineCacheBuffer::contains(addr)) {
955 st->print_cr(INTPTR_FORMAT " is pointing into InlineCacheBuffer", p2i(addr));
956 return;
957 }
958 VtableStub* v = VtableStubs::stub_containing(addr);
959 if (v != NULL) {
960 st->print_cr(INTPTR_FORMAT " is at entry_point+%d in a vtable stub", p2i(addr), (int)(addr - v->entry_point()));
961 v->print_on(st);
962 st->cr();
963 return;
964 }
965 }
966 nmethod* nm = b->as_nmethod_or_null();
967 if (nm != NULL) {
968 ResourceMark rm;
969 st->print(INTPTR_FORMAT " is at entry_point+%d in (nmethod*)" INTPTR_FORMAT,
970 p2i(addr), (int)(addr - nm->entry_point()), p2i(nm));
971 if (verbose) {
972 st->print(" for ");
973 nm->method()->print_value_on(st);
974 }
975 st->cr();
976 nm->print_nmethod(verbose);
977 return;
978 }
979 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in ", p2i(addr), (int)(addr - b->code_begin()));
980 b->print_on(st);
981 return;
982 }
983
984 if (Universe::heap()->is_in(addr)) {
985 HeapWord* p = Universe::heap()->block_start(addr);
986 bool print = false;
987 // If we couldn't find it it just may mean that heap wasn't parsable
988 // See if we were just given an oop directly
989 if (p != NULL && Universe::heap()->block_is_obj(p)) {
990 print = true;
991 } else if (p == NULL && ((oopDesc*)addr)->is_oop()) {
992 p = (HeapWord*) addr;
993 print = true;
994 }
995 if (print) {
996 if (p == (HeapWord*) addr) {
997 st->print_cr(INTPTR_FORMAT " is an oop", p2i(addr));
998 } else {
999 st->print_cr(INTPTR_FORMAT " is pointing into object: " INTPTR_FORMAT, p2i(addr), p2i(p));
1000 }
1001 oop(p)->print_on(st);
1002 return;
1003 }
1004 } else {
1005 if (Universe::heap()->is_in_reserved(addr)) {
1006 st->print_cr(INTPTR_FORMAT " is an unallocated location "
1007 "in the heap", p2i(addr));
1008 return;
1009 }
1010 }
1011 if (JNIHandles::is_global_handle((jobject) addr)) {
1012 st->print_cr(INTPTR_FORMAT " is a global jni handle", p2i(addr));
1013 return;
1014 }
1015 if (JNIHandles::is_weak_global_handle((jobject) addr)) {
1016 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", p2i(addr));
1017 return;
1018 }
1019 #ifndef PRODUCT
1020 // we don't keep the block list in product mode
1021 if (JNIHandleBlock::any_contains((jobject) addr)) {
1022 st->print_cr(INTPTR_FORMAT " is a local jni handle", p2i(addr));
1023 return;
1024 }
1025 #endif
1026
1027 for(JavaThread *thread = Threads::first(); thread; thread = thread->next()) {
1028 // Check for privilege stack
1029 if (thread->privileged_stack_top() != NULL &&
1030 thread->privileged_stack_top()->contains(addr)) {
1031 st->print_cr(INTPTR_FORMAT " is pointing into the privilege stack "
1032 "for thread: " INTPTR_FORMAT, p2i(addr), p2i(thread));
1033 if (verbose) thread->print_on(st);
1034 return;
1035 }
1036 // If the addr is a java thread print information about that.
1037 if (addr == (address)thread) {
1038 if (verbose) {
1039 thread->print_on(st);
1040 } else {
1041 st->print_cr(INTPTR_FORMAT " is a thread", p2i(addr));
1042 }
1043 return;
1044 }
1045 // If the addr is in the stack region for this thread then report that
1046 // and print thread info
1047 if (thread->on_local_stack(addr)) {
1048 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: "
1049 INTPTR_FORMAT, p2i(addr), p2i(thread));
1050 if (verbose) thread->print_on(st);
1051 return;
1052 }
1053
1054 }
1055
1056 // Check if in metaspace and print types that have vptrs (only method now)
1057 if (Metaspace::contains(addr)) {
1058 if (Method::has_method_vptr((const void*)addr)) {
1059 ((Method*)addr)->print_value_on(st);
1060 st->cr();
1061 } else {
1062 // Use addr->print() from the debugger instead (not here)
1063 st->print_cr(INTPTR_FORMAT " is pointing into metadata", p2i(addr));
1064 }
1065 return;
1066 }
1067
1068 // Try an OS specific find
1069 if (os::find(addr, st)) {
1070 return;
1071 }
1072
1073 st->print_cr(INTPTR_FORMAT " is an unknown value", p2i(addr));
1074 }
1075
1076 // Looks like all platforms except IA64 can use the same function to check
1077 // if C stack is walkable beyond current frame. The check for fp() is not
1078 // necessary on Sparc, but it's harmless.
1079 bool os::is_first_C_frame(frame* fr) {
1080 #if (defined(IA64) && !defined(AIX)) && !defined(_WIN32)
1081 // On IA64 we have to check if the callers bsp is still valid
1082 // (i.e. within the register stack bounds).
1083 // Notice: this only works for threads created by the VM and only if
1084 // we walk the current stack!!! If we want to be able to walk
1085 // arbitrary other threads, we'll have to somehow store the thread
1086 // object in the frame.
1087 Thread *thread = Thread::current();
1088 if ((address)fr->fp() <=
1089 thread->register_stack_base() HPUX_ONLY(+ 0x0) LINUX_ONLY(+ 0x50)) {
1090 // This check is a little hacky, because on Linux the first C
1091 // frame's ('start_thread') register stack frame starts at
1092 // "register_stack_base + 0x48" while on HPUX, the first C frame's
1093 // ('__pthread_bound_body') register stack frame seems to really
1094 // start at "register_stack_base".
1095 return true;
1096 } else {
1097 return false;
1098 }
1099 #elif defined(IA64) && defined(_WIN32)
1100 return true;
1101 #else
1102 // Load up sp, fp, sender sp and sender fp, check for reasonable values.
1103 // Check usp first, because if that's bad the other accessors may fault
1104 // on some architectures. Ditto ufp second, etc.
1105 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1);
1106 // sp on amd can be 32 bit aligned.
1107 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1);
1108
1109 uintptr_t usp = (uintptr_t)fr->sp();
1110 if ((usp & sp_align_mask) != 0) return true;
1111
1112 uintptr_t ufp = (uintptr_t)fr->fp();
1113 if ((ufp & fp_align_mask) != 0) return true;
1114
1115 uintptr_t old_sp = (uintptr_t)fr->sender_sp();
1116 if ((old_sp & sp_align_mask) != 0) return true;
1117 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true;
1118
1119 uintptr_t old_fp = (uintptr_t)fr->link();
1120 if ((old_fp & fp_align_mask) != 0) return true;
1121 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true;
1122
1123 // stack grows downwards; if old_fp is below current fp or if the stack
1124 // frame is too large, either the stack is corrupted or fp is not saved
1125 // on stack (i.e. on x86, ebp may be used as general register). The stack
1126 // is not walkable beyond current frame.
1127 if (old_fp < ufp) return true;
1128 if (old_fp - ufp > 64 * K) return true;
1129
1130 return false;
1131 #endif
1132 }
1133
1134 #ifdef ASSERT
1135 extern "C" void test_random() {
1136 const double m = 2147483647;
1137 double mean = 0.0, variance = 0.0, t;
1138 long reps = 10000;
1139 unsigned long seed = 1;
1140
1141 tty->print_cr("seed %ld for %ld repeats...", seed, reps);
1142 os::init_random(seed);
1143 long num;
1144 for (int k = 0; k < reps; k++) {
1145 num = os::random();
1146 double u = (double)num / m;
1147 assert(u >= 0.0 && u <= 1.0, "bad random number!");
1148
1149 // calculate mean and variance of the random sequence
1150 mean += u;
1151 variance += (u*u);
1152 }
1153 mean /= reps;
1154 variance /= (reps - 1);
1155
1156 assert(num == 1043618065, "bad seed");
1157 tty->print_cr("mean of the 1st 10000 numbers: %f", mean);
1158 tty->print_cr("variance of the 1st 10000 numbers: %f", variance);
1159 const double eps = 0.0001;
1160 t = fabsd(mean - 0.5018);
1161 assert(t < eps, "bad mean");
1162 t = (variance - 0.3355) < 0.0 ? -(variance - 0.3355) : variance - 0.3355;
1163 assert(t < eps, "bad variance");
1164 }
1165 #endif
1166
1167
1168 // Set up the boot classpath.
1169
1170 char* os::format_boot_path(const char* format_string,
1171 const char* home,
1172 int home_len,
1173 char fileSep,
1174 char pathSep) {
1175 assert((fileSep == '/' && pathSep == ':') ||
1176 (fileSep == '\\' && pathSep == ';'), "unexpected separator chars");
1177
1178 // Scan the format string to determine the length of the actual
1179 // boot classpath, and handle platform dependencies as well.
1180 int formatted_path_len = 0;
1181 const char* p;
1182 for (p = format_string; *p != 0; ++p) {
1183 if (*p == '%') formatted_path_len += home_len - 1;
1184 ++formatted_path_len;
1185 }
1186
1187 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal);
1188 if (formatted_path == NULL) {
1189 return NULL;
1190 }
1191
1192 // Create boot classpath from format, substituting separator chars and
1193 // java home directory.
1194 char* q = formatted_path;
1195 for (p = format_string; *p != 0; ++p) {
1196 switch (*p) {
1197 case '%':
1198 strcpy(q, home);
1199 q += home_len;
1200 break;
1201 case '/':
1202 *q++ = fileSep;
1203 break;
1204 case ':':
1205 *q++ = pathSep;
1206 break;
1207 default:
1208 *q++ = *p;
1209 }
1210 }
1211 *q = '\0';
1212
1213 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched");
1214 return formatted_path;
1215 }
1216
1217 bool os::set_boot_path(char fileSep, char pathSep) {
1218 const char* home = Arguments::get_java_home();
1219 int home_len = (int)strlen(home);
1220
1221 struct stat st;
1222
1223 // modular image if "modules" jimage exists
1224 char* jimage = format_boot_path("%/lib/" MODULES_IMAGE_NAME, home, home_len, fileSep, pathSep);
1225 if (jimage == NULL) return false;
1226 bool has_jimage = (os::stat(jimage, &st) == 0);
1227 if (has_jimage) {
1228 Arguments::set_sysclasspath(jimage, true);
1229 FREE_C_HEAP_ARRAY(char, jimage);
1230 return true;
1231 }
1232 FREE_C_HEAP_ARRAY(char, jimage);
1233
1234 // check if developer build with exploded modules
1235 char* base_classes = format_boot_path("%/modules/" JAVA_BASE_NAME, home, home_len, fileSep, pathSep);
1236 if (base_classes == NULL) return false;
1237 if (os::stat(base_classes, &st) == 0) {
1238 Arguments::set_sysclasspath(base_classes, false);
1239 FREE_C_HEAP_ARRAY(char, base_classes);
1240 return true;
1241 }
1242 FREE_C_HEAP_ARRAY(char, base_classes);
1243
1244 return false;
1245 }
1246
1247 /*
1248 * Splits a path, based on its separator, the number of
1249 * elements is returned back in n.
1250 * It is the callers responsibility to:
1251 * a> check the value of n, and n may be 0.
1252 * b> ignore any empty path elements
1253 * c> free up the data.
1254 */
1255 char** os::split_path(const char* path, int* n) {
1256 *n = 0;
1257 if (path == NULL || strlen(path) == 0) {
1258 return NULL;
1259 }
1260 const char psepchar = *os::path_separator();
1261 char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal);
1262 if (inpath == NULL) {
1263 return NULL;
1264 }
1265 strcpy(inpath, path);
1266 int count = 1;
1267 char* p = strchr(inpath, psepchar);
1268 // Get a count of elements to allocate memory
1269 while (p != NULL) {
1270 count++;
1271 p++;
1272 p = strchr(p, psepchar);
1273 }
1274 char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count, mtInternal);
1275 if (opath == NULL) {
1276 return NULL;
1277 }
1278
1279 // do the actual splitting
1280 p = inpath;
1281 for (int i = 0 ; i < count ; i++) {
1282 size_t len = strcspn(p, os::path_separator());
1283 if (len > JVM_MAXPATHLEN) {
1284 return NULL;
1285 }
1286 // allocate the string and add terminator storage
1287 char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
1288 if (s == NULL) {
1289 return NULL;
1290 }
1291 strncpy(s, p, len);
1292 s[len] = '\0';
1293 opath[i] = s;
1294 p += len + 1;
1295 }
1296 FREE_C_HEAP_ARRAY(char, inpath);
1297 *n = count;
1298 return opath;
1299 }
1300
1301 void os::set_memory_serialize_page(address page) {
1302 int count = log2_intptr(sizeof(class JavaThread)) - log2_intptr(64);
1303 _mem_serialize_page = (volatile int32_t *)page;
1304 // We initialize the serialization page shift count here
1305 // We assume a cache line size of 64 bytes
1306 assert(SerializePageShiftCount == count, "JavaThread size changed; "
1307 "SerializePageShiftCount constant should be %d", count);
1308 set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t)));
1309 }
1310
1311 static volatile intptr_t SerializePageLock = 0;
1312
1313 // This method is called from signal handler when SIGSEGV occurs while the current
1314 // thread tries to store to the "read-only" memory serialize page during state
1315 // transition.
1316 void os::block_on_serialize_page_trap() {
1317 log_debug(safepoint)("Block until the serialize page permission restored");
1318
1319 // When VMThread is holding the SerializePageLock during modifying the
1320 // access permission of the memory serialize page, the following call
1321 // will block until the permission of that page is restored to rw.
1322 // Generally, it is unsafe to manipulate locks in signal handlers, but in
1323 // this case, it's OK as the signal is synchronous and we know precisely when
1324 // it can occur.
1325 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page");
1326 Thread::muxRelease(&SerializePageLock);
1327 }
1328
1329 // Serialize all thread state variables
1330 void os::serialize_thread_states() {
1331 // On some platforms such as Solaris & Linux, the time duration of the page
1332 // permission restoration is observed to be much longer than expected due to
1333 // scheduler starvation problem etc. To avoid the long synchronization
1334 // time and expensive page trap spinning, 'SerializePageLock' is used to block
1335 // the mutator thread if such case is encountered. See bug 6546278 for details.
1336 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states");
1337 os::protect_memory((char *)os::get_memory_serialize_page(),
1338 os::vm_page_size(), MEM_PROT_READ);
1339 os::protect_memory((char *)os::get_memory_serialize_page(),
1340 os::vm_page_size(), MEM_PROT_RW);
1341 Thread::muxRelease(&SerializePageLock);
1342 }
1343
1344 // Returns true if the current stack pointer is above the stack shadow
1345 // pages, false otherwise.
1346 bool os::stack_shadow_pages_available(Thread *thread, const methodHandle& method, address sp) {
1347 if (!thread->is_Java_thread()) return false;
1348 // Check if we have StackShadowPages above the yellow zone. This parameter
1349 // is dependent on the depth of the maximum VM call stack possible from
1350 // the handler for stack overflow. 'instanceof' in the stack overflow
1351 // handler or a println uses at least 8k stack of VM and native code
1352 // respectively.
1353 const int framesize_in_bytes =
1354 Interpreter::size_top_interpreter_activation(method()) * wordSize;
1355
1356 address limit = ((JavaThread*)thread)->stack_end() +
1357 (JavaThread::stack_guard_zone_size() + JavaThread::stack_shadow_zone_size());
1358
1359 return sp > (limit + framesize_in_bytes);
1360 }
1361
1362 size_t os::page_size_for_region(size_t region_size, size_t min_pages, bool must_be_aligned) {
1363 assert(min_pages > 0, "sanity");
1364 if (UseLargePages) {
1365 const size_t max_page_size = region_size / min_pages;
1366
1367 for (size_t i = 0; _page_sizes[i] != 0; ++i) {
1368 const size_t page_size = _page_sizes[i];
1369 if (page_size <= max_page_size) {
1370 if (!must_be_aligned || is_size_aligned(region_size, page_size)) {
1371 return page_size;
1372 }
1373 }
1374 }
1375 }
1376
1377 return vm_page_size();
1378 }
1379
1380 size_t os::page_size_for_region_aligned(size_t region_size, size_t min_pages) {
1381 return page_size_for_region(region_size, min_pages, true);
1382 }
1383
1384 size_t os::page_size_for_region_unaligned(size_t region_size, size_t min_pages) {
1385 return page_size_for_region(region_size, min_pages, false);
1386 }
1387
1388 static const char* errno_to_string (int e, bool short_text) {
1389 #define ALL_SHARED_ENUMS(X) \
1390 X(E2BIG, "Argument list too long") \
1391 X(EACCES, "Permission denied") \
1392 X(EADDRINUSE, "Address in use") \
1393 X(EADDRNOTAVAIL, "Address not available") \
1394 X(EAFNOSUPPORT, "Address family not supported") \
1395 X(EAGAIN, "Resource unavailable, try again") \
1396 X(EALREADY, "Connection already in progress") \
1397 X(EBADF, "Bad file descriptor") \
1398 X(EBADMSG, "Bad message") \
1399 X(EBUSY, "Device or resource busy") \
1400 X(ECANCELED, "Operation canceled") \
1401 X(ECHILD, "No child processes") \
1402 X(ECONNABORTED, "Connection aborted") \
1403 X(ECONNREFUSED, "Connection refused") \
1404 X(ECONNRESET, "Connection reset") \
1405 X(EDEADLK, "Resource deadlock would occur") \
1406 X(EDESTADDRREQ, "Destination address required") \
1407 X(EDOM, "Mathematics argument out of domain of function") \
1408 X(EEXIST, "File exists") \
1409 X(EFAULT, "Bad address") \
1410 X(EFBIG, "File too large") \
1411 X(EHOSTUNREACH, "Host is unreachable") \
1412 X(EIDRM, "Identifier removed") \
1413 X(EILSEQ, "Illegal byte sequence") \
1414 X(EINPROGRESS, "Operation in progress") \
1415 X(EINTR, "Interrupted function") \
1416 X(EINVAL, "Invalid argument") \
1417 X(EIO, "I/O error") \
1418 X(EISCONN, "Socket is connected") \
1419 X(EISDIR, "Is a directory") \
1420 X(ELOOP, "Too many levels of symbolic links") \
1421 X(EMFILE, "Too many open files") \
1422 X(EMLINK, "Too many links") \
1423 X(EMSGSIZE, "Message too large") \
1424 X(ENAMETOOLONG, "Filename too long") \
1425 X(ENETDOWN, "Network is down") \
1426 X(ENETRESET, "Connection aborted by network") \
1427 X(ENETUNREACH, "Network unreachable") \
1428 X(ENFILE, "Too many files open in system") \
1429 X(ENOBUFS, "No buffer space available") \
1430 X(ENODATA, "No message is available on the STREAM head read queue") \
1431 X(ENODEV, "No such device") \
1432 X(ENOENT, "No such file or directory") \
1433 X(ENOEXEC, "Executable file format error") \
1434 X(ENOLCK, "No locks available") \
1435 X(ENOLINK, "Reserved") \
1436 X(ENOMEM, "Not enough space") \
1437 X(ENOMSG, "No message of the desired type") \
1438 X(ENOPROTOOPT, "Protocol not available") \
1439 X(ENOSPC, "No space left on device") \
1440 X(ENOSR, "No STREAM resources") \
1441 X(ENOSTR, "Not a STREAM") \
1442 X(ENOSYS, "Function not supported") \
1443 X(ENOTCONN, "The socket is not connected") \
1444 X(ENOTDIR, "Not a directory") \
1445 X(ENOTEMPTY, "Directory not empty") \
1446 X(ENOTSOCK, "Not a socket") \
1447 X(ENOTSUP, "Not supported") \
1448 X(ENOTTY, "Inappropriate I/O control operation") \
1449 X(ENXIO, "No such device or address") \
1450 X(EOPNOTSUPP, "Operation not supported on socket") \
1451 X(EOVERFLOW, "Value too large to be stored in data type") \
1452 X(EPERM, "Operation not permitted") \
1453 X(EPIPE, "Broken pipe") \
1454 X(EPROTO, "Protocol error") \
1455 X(EPROTONOSUPPORT, "Protocol not supported") \
1456 X(EPROTOTYPE, "Protocol wrong type for socket") \
1457 X(ERANGE, "Result too large") \
1458 X(EROFS, "Read-only file system") \
1459 X(ESPIPE, "Invalid seek") \
1460 X(ESRCH, "No such process") \
1461 X(ETIME, "Stream ioctl() timeout") \
1462 X(ETIMEDOUT, "Connection timed out") \
1463 X(ETXTBSY, "Text file busy") \
1464 X(EWOULDBLOCK, "Operation would block") \
1465 X(EXDEV, "Cross-device link")
1466
1467 #define DEFINE_ENTRY(e, text) { e, #e, text },
1468
1469 static const struct {
1470 int v;
1471 const char* short_text;
1472 const char* long_text;
1473 } table [] = {
1474
1475 ALL_SHARED_ENUMS(DEFINE_ENTRY)
1476
1477 // The following enums are not defined on all platforms.
1478 #ifdef ESTALE
1479 DEFINE_ENTRY(ESTALE, "Reserved")
1480 #endif
1481 #ifdef EDQUOT
1482 DEFINE_ENTRY(EDQUOT, "Reserved")
1483 #endif
1484 #ifdef EMULTIHOP
1485 DEFINE_ENTRY(EMULTIHOP, "Reserved")
1486 #endif
1487
1488 // End marker.
1489 { -1, "Unknown errno", "Unknown error" }
1490
1491 };
1492
1493 #undef DEFINE_ENTRY
1494 #undef ALL_FLAGS
1495
1496 int i = 0;
1497 while (table[i].v != -1 && table[i].v != e) {
1498 i ++;
1499 }
1500
1501 return short_text ? table[i].short_text : table[i].long_text;
1502
1503 }
1504
1505 const char* os::strerror(int e) {
1506 return errno_to_string(e, false);
1507 }
1508
1509 const char* os::errno_name(int e) {
1510 return errno_to_string(e, true);
1511 }
1512
1513 void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count) {
1514 LogTarget(Info, pagesize) log;
1515 if (log.is_enabled()) {
1516 LogStreamCHeap out(log);
1517
1518 out.print("%s: ", str);
1519 for (int i = 0; i < count; ++i) {
1520 out.print(" " SIZE_FORMAT, page_sizes[i]);
1521 }
1522 out.cr();
1523 }
1524 }
1525
1526 #define trace_page_size_params(size) byte_size_in_exact_unit(size), exact_unit_for_byte_size(size)
1527
1528 void os::trace_page_sizes(const char* str,
1529 const size_t region_min_size,
1530 const size_t region_max_size,
1531 const size_t page_size,
1532 const char* base,
1533 const size_t size) {
1534
1535 log_info(pagesize)("%s: "
1536 " min=" SIZE_FORMAT "%s"
1537 " max=" SIZE_FORMAT "%s"
1538 " base=" PTR_FORMAT
1539 " page_size=" SIZE_FORMAT "%s"
1540 " size=" SIZE_FORMAT "%s",
1541 str,
1542 trace_page_size_params(region_min_size),
1543 trace_page_size_params(region_max_size),
1544 p2i(base),
1545 trace_page_size_params(page_size),
1546 trace_page_size_params(size));
1547 }
1548
1549 void os::trace_page_sizes_for_requested_size(const char* str,
1550 const size_t requested_size,
1551 const size_t page_size,
1552 const size_t alignment,
1553 const char* base,
1554 const size_t size) {
1555
1556 log_info(pagesize)("%s:"
1557 " req_size=" SIZE_FORMAT "%s"
1558 " base=" PTR_FORMAT
1559 " page_size=" SIZE_FORMAT "%s"
1560 " alignment=" SIZE_FORMAT "%s"
1561 " size=" SIZE_FORMAT "%s",
1562 str,
1563 trace_page_size_params(requested_size),
1564 p2i(base),
1565 trace_page_size_params(page_size),
1566 trace_page_size_params(alignment),
1567 trace_page_size_params(size));
1568 }
1569
1570
1571 // This is the working definition of a server class machine:
1572 // >= 2 physical CPU's and >=2GB of memory, with some fuzz
1573 // because the graphics memory (?) sometimes masks physical memory.
1574 // If you want to change the definition of a server class machine
1575 // on some OS or platform, e.g., >=4GB on Windows platforms,
1576 // then you'll have to parameterize this method based on that state,
1577 // as was done for logical processors here, or replicate and
1578 // specialize this method for each platform. (Or fix os to have
1579 // some inheritance structure and use subclassing. Sigh.)
1580 // If you want some platform to always or never behave as a server
1581 // class machine, change the setting of AlwaysActAsServerClassMachine
1582 // and NeverActAsServerClassMachine in globals*.hpp.
1583 bool os::is_server_class_machine() {
1584 // First check for the early returns
1585 if (NeverActAsServerClassMachine) {
1586 return false;
1587 }
1588 if (AlwaysActAsServerClassMachine) {
1589 return true;
1590 }
1591 // Then actually look at the machine
1592 bool result = false;
1593 const unsigned int server_processors = 2;
1594 const julong server_memory = 2UL * G;
1595 // We seem not to get our full complement of memory.
1596 // We allow some part (1/8?) of the memory to be "missing",
1597 // based on the sizes of DIMMs, and maybe graphics cards.
1598 const julong missing_memory = 256UL * M;
1599
1600 /* Is this a server class machine? */
1601 if ((os::active_processor_count() >= (int)server_processors) &&
1602 (os::physical_memory() >= (server_memory - missing_memory))) {
1603 const unsigned int logical_processors =
1604 VM_Version::logical_processors_per_package();
1605 if (logical_processors > 1) {
1606 const unsigned int physical_packages =
1607 os::active_processor_count() / logical_processors;
1608 if (physical_packages >= server_processors) {
1609 result = true;
1610 }
1611 } else {
1612 result = true;
1613 }
1614 }
1615 return result;
1616 }
1617
1618 void os::initialize_initial_active_processor_count() {
1619 assert(_initial_active_processor_count == 0, "Initial active processor count already set.");
1620 _initial_active_processor_count = active_processor_count();
1621 log_debug(os)("Initial active processor count set to %d" , _initial_active_processor_count);
1622 }
1623
1624 void os::SuspendedThreadTask::run() {
1625 assert(Threads_lock->owned_by_self() || (_thread == VMThread::vm_thread()), "must have threads lock to call this");
1626 internal_do_task();
1627 _done = true;
1628 }
1629
1630 bool os::create_stack_guard_pages(char* addr, size_t bytes) {
1631 return os::pd_create_stack_guard_pages(addr, bytes);
1632 }
1633
1634 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint) {
1635 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1636 if (result != NULL) {
1637 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1638 }
1639
1640 return result;
1641 }
1642
1643 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint,
1644 MEMFLAGS flags) {
1645 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1646 if (result != NULL) {
1647 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1648 MemTracker::record_virtual_memory_type((address)result, flags);
1649 }
1650
1651 return result;
1652 }
1653
1654 char* os::attempt_reserve_memory_at(size_t bytes, char* addr) {
1655 char* result = pd_attempt_reserve_memory_at(bytes, addr);
1656 if (result != NULL) {
1657 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1658 }
1659 return result;
1660 }
1661
1662 void os::split_reserved_memory(char *base, size_t size,
1663 size_t split, bool realloc) {
1664 pd_split_reserved_memory(base, size, split, realloc);
1665 }
1666
1667 bool os::commit_memory(char* addr, size_t bytes, bool executable) {
1668 bool res = pd_commit_memory(addr, bytes, executable);
1669 if (res) {
1670 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1671 }
1672 return res;
1673 }
1674
1675 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint,
1676 bool executable) {
1677 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable);
1678 if (res) {
1679 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1680 }
1681 return res;
1682 }
1683
1684 void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable,
1685 const char* mesg) {
1686 pd_commit_memory_or_exit(addr, bytes, executable, mesg);
1687 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1688 }
1689
1690 void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint,
1691 bool executable, const char* mesg) {
1692 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg);
1693 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1694 }
1695
1696 bool os::uncommit_memory(char* addr, size_t bytes) {
1697 bool res;
1698 if (MemTracker::tracking_level() > NMT_minimal) {
1699 Tracker tkr = MemTracker::get_virtual_memory_uncommit_tracker();
1700 res = pd_uncommit_memory(addr, bytes);
1701 if (res) {
1702 tkr.record((address)addr, bytes);
1703 }
1704 } else {
1705 res = pd_uncommit_memory(addr, bytes);
1706 }
1707 return res;
1708 }
1709
1710 bool os::release_memory(char* addr, size_t bytes) {
1711 bool res;
1712 if (MemTracker::tracking_level() > NMT_minimal) {
1713 Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
1714 res = pd_release_memory(addr, bytes);
1715 if (res) {
1716 tkr.record((address)addr, bytes);
1717 }
1718 } else {
1719 res = pd_release_memory(addr, bytes);
1720 }
1721 return res;
1722 }
1723
1724 void os::pretouch_memory(void* start, void* end, size_t page_size) {
1725 for (volatile char *p = (char*)start; p < (char*)end; p += page_size) {
1726 *p = 0;
1727 }
1728 }
1729
1730 char* os::map_memory(int fd, const char* file_name, size_t file_offset,
1731 char *addr, size_t bytes, bool read_only,
1732 bool allow_exec) {
1733 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec);
1734 if (result != NULL) {
1735 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC);
1736 }
1737 return result;
1738 }
1739
1740 char* os::remap_memory(int fd, const char* file_name, size_t file_offset,
1741 char *addr, size_t bytes, bool read_only,
1742 bool allow_exec) {
1743 return pd_remap_memory(fd, file_name, file_offset, addr, bytes,
1744 read_only, allow_exec);
1745 }
1746
1747 bool os::unmap_memory(char *addr, size_t bytes) {
1748 bool result;
1749 if (MemTracker::tracking_level() > NMT_minimal) {
1750 Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
1751 result = pd_unmap_memory(addr, bytes);
1752 if (result) {
1753 tkr.record((address)addr, bytes);
1754 }
1755 } else {
1756 result = pd_unmap_memory(addr, bytes);
1757 }
1758 return result;
1759 }
1760
1761 void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) {
1762 pd_free_memory(addr, bytes, alignment_hint);
1763 }
1764
1765 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
1766 pd_realign_memory(addr, bytes, alignment_hint);
1767 }
1768
1769 #ifndef _WINDOWS
1770 /* try to switch state from state "from" to state "to"
1771 * returns the state set after the method is complete
1772 */
1773 os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from,
1774 os::SuspendResume::State to)
1775 {
1776 os::SuspendResume::State result =
1777 (os::SuspendResume::State) Atomic::cmpxchg((jint) to, (jint *) &_state, (jint) from);
1778 if (result == from) {
1779 // success
1780 return to;
1781 }
1782 return result;
1783 }
1784 #endif