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