1 /*
2 * Copyright (c) 1997, 2016, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "classfile/classLoader.hpp"
27 #include "classfile/javaClasses.hpp"
28 #include "classfile/systemDictionary.hpp"
29 #include "classfile/vmSymbols.hpp"
30 #include "code/codeCache.hpp"
31 #include "code/icBuffer.hpp"
32 #include "code/vtableStubs.hpp"
33 #include "gc/shared/vmGCOperations.hpp"
34 #include "interpreter/interpreter.hpp"
35 #include "logging/log.hpp"
36 #include "logging/logStream.inline.hpp"
37 #include "memory/allocation.inline.hpp"
38 #ifdef ASSERT
39 #include "memory/guardedMemory.hpp"
40 #endif
41 #include "memory/resourceArea.hpp"
42 #include "oops/oop.inline.hpp"
43 #include "prims/jvm.h"
44 #include "prims/jvm_misc.hpp"
45 #include "prims/privilegedStack.hpp"
46 #include "runtime/arguments.hpp"
47 #include "runtime/atomic.hpp"
48 #include "runtime/frame.inline.hpp"
49 #include "runtime/interfaceSupport.hpp"
50 #include "runtime/java.hpp"
51 #include "runtime/javaCalls.hpp"
52 #include "runtime/mutexLocker.hpp"
53 #include "runtime/os.inline.hpp"
54 #include "runtime/stubRoutines.hpp"
55 #include "runtime/thread.inline.hpp"
56 #include "runtime/vm_version.hpp"
57 #include "services/attachListener.hpp"
58 #include "services/mallocTracker.hpp"
59 #include "services/memTracker.hpp"
60 #include "services/nmtCommon.hpp"
61 #include "services/threadService.hpp"
62 #include "utilities/defaultStream.hpp"
63 #include "utilities/events.hpp"
64
65 # include <signal.h>
66 # include <errno.h>
67
68 OSThread* os::_starting_thread = NULL;
69 address os::_polling_page = NULL;
70 volatile int32_t* os::_mem_serialize_page = NULL;
71 uintptr_t os::_serialize_page_mask = 0;
72 long os::_rand_seed = 1;
73 int os::_processor_count = 0;
74 int os::_initial_active_processor_count = 0;
75 size_t os::_page_sizes[os::page_sizes_max];
76
77 #ifndef PRODUCT
78 julong os::num_mallocs = 0; // # of calls to malloc/realloc
79 julong os::alloc_bytes = 0; // # of bytes allocated
80 julong os::num_frees = 0; // # of calls to free
81 julong os::free_bytes = 0; // # of bytes freed
82 #endif
83
84 static juint cur_malloc_words = 0; // current size for MallocMaxTestWords
85
86 void os_init_globals() {
87 // Called from init_globals().
88 // See Threads::create_vm() in thread.cpp, and init.cpp.
89 os::init_globals();
90 }
91
92 // Fill in buffer with current local time as an ISO-8601 string.
93 // E.g., yyyy-mm-ddThh:mm:ss-zzzz.
94 // Returns buffer, or NULL if it failed.
95 // This would mostly be a call to
96 // strftime(...., "%Y-%m-%d" "T" "%H:%M:%S" "%z", ....)
97 // except that on Windows the %z behaves badly, so we do it ourselves.
98 // Also, people wanted milliseconds on there,
99 // and strftime doesn't do milliseconds.
100 char* os::iso8601_time(char* buffer, size_t buffer_length, bool utc) {
101 // Output will be of the form "YYYY-MM-DDThh:mm:ss.mmm+zzzz\0"
102 // 1 2
103 // 12345678901234567890123456789
104 // format string: "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d"
105 static const size_t needed_buffer = 29;
106
107 // Sanity check the arguments
108 if (buffer == NULL) {
109 assert(false, "NULL buffer");
110 return NULL;
111 }
112 if (buffer_length < needed_buffer) {
113 assert(false, "buffer_length too small");
114 return NULL;
115 }
116 // Get the current time
117 jlong milliseconds_since_19700101 = javaTimeMillis();
118 const int milliseconds_per_microsecond = 1000;
119 const time_t seconds_since_19700101 =
120 milliseconds_since_19700101 / milliseconds_per_microsecond;
121 const int milliseconds_after_second =
122 milliseconds_since_19700101 % milliseconds_per_microsecond;
123 // Convert the time value to a tm and timezone variable
124 struct tm time_struct;
125 if (utc) {
126 if (gmtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
127 assert(false, "Failed gmtime_pd");
128 return NULL;
129 }
130 } else {
131 if (localtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
132 assert(false, "Failed localtime_pd");
133 return NULL;
134 }
135 }
136 #if defined(_ALLBSD_SOURCE)
137 const time_t zone = (time_t) time_struct.tm_gmtoff;
138 #else
139 const time_t zone = timezone;
140 #endif
141
142 // If daylight savings time is in effect,
143 // we are 1 hour East of our time zone
144 const time_t seconds_per_minute = 60;
145 const time_t minutes_per_hour = 60;
146 const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour;
147 time_t UTC_to_local = zone;
148 if (time_struct.tm_isdst > 0) {
149 UTC_to_local = UTC_to_local - seconds_per_hour;
150 }
151
152 // No offset when dealing with UTC
153 if (utc) {
154 UTC_to_local = 0;
155 }
156
157 // Compute the time zone offset.
158 // localtime_pd() sets timezone to the difference (in seconds)
159 // between UTC and and local time.
160 // ISO 8601 says we need the difference between local time and UTC,
161 // we change the sign of the localtime_pd() result.
162 const time_t local_to_UTC = -(UTC_to_local);
163 // Then we have to figure out if if we are ahead (+) or behind (-) UTC.
164 char sign_local_to_UTC = '+';
165 time_t abs_local_to_UTC = local_to_UTC;
166 if (local_to_UTC < 0) {
167 sign_local_to_UTC = '-';
168 abs_local_to_UTC = -(abs_local_to_UTC);
169 }
170 // Convert time zone offset seconds to hours and minutes.
171 const time_t zone_hours = (abs_local_to_UTC / seconds_per_hour);
172 const time_t zone_min =
173 ((abs_local_to_UTC % seconds_per_hour) / seconds_per_minute);
174
175 // Print an ISO 8601 date and time stamp into the buffer
176 const int year = 1900 + time_struct.tm_year;
177 const int month = 1 + time_struct.tm_mon;
178 const int printed = jio_snprintf(buffer, buffer_length,
179 "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d",
180 year,
181 month,
182 time_struct.tm_mday,
183 time_struct.tm_hour,
184 time_struct.tm_min,
185 time_struct.tm_sec,
186 milliseconds_after_second,
187 sign_local_to_UTC,
188 zone_hours,
189 zone_min);
190 if (printed == 0) {
191 assert(false, "Failed jio_printf");
192 return NULL;
193 }
194 return buffer;
195 }
196
197 OSReturn os::set_priority(Thread* thread, ThreadPriority p) {
198 #ifdef ASSERT
199 if (!(!thread->is_Java_thread() ||
200 Thread::current() == thread ||
201 Threads_lock->owned_by_self()
202 || thread->is_Compiler_thread()
203 )) {
204 assert(false, "possibility of dangling Thread pointer");
205 }
206 #endif
207
208 if (p >= MinPriority && p <= MaxPriority) {
209 int priority = java_to_os_priority[p];
210 return set_native_priority(thread, priority);
211 } else {
212 assert(false, "Should not happen");
213 return OS_ERR;
214 }
215 }
216
217 // The mapping from OS priority back to Java priority may be inexact because
218 // Java priorities can map M:1 with native priorities. If you want the definite
219 // Java priority then use JavaThread::java_priority()
220 OSReturn os::get_priority(const Thread* const thread, ThreadPriority& priority) {
221 int p;
222 int os_prio;
223 OSReturn ret = get_native_priority(thread, &os_prio);
224 if (ret != OS_OK) return ret;
225
226 if (java_to_os_priority[MaxPriority] > java_to_os_priority[MinPriority]) {
227 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] > os_prio; p--) ;
228 } else {
229 // niceness values are in reverse order
230 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] < os_prio; p--) ;
231 }
232 priority = (ThreadPriority)p;
233 return OS_OK;
234 }
235
236
237 // --------------------- sun.misc.Signal (optional) ---------------------
238
239
240 // SIGBREAK is sent by the keyboard to query the VM state
241 #ifndef SIGBREAK
242 #define SIGBREAK SIGQUIT
243 #endif
244
245 // sigexitnum_pd is a platform-specific special signal used for terminating the Signal thread.
246
247
248 static void signal_thread_entry(JavaThread* thread, TRAPS) {
249 os::set_priority(thread, NearMaxPriority);
250 while (true) {
251 int sig;
252 {
253 // FIXME : Currently we have not decided what should be the status
254 // for this java thread blocked here. Once we decide about
255 // that we should fix this.
256 sig = os::signal_wait();
257 }
258 if (sig == os::sigexitnum_pd()) {
259 // Terminate the signal thread
260 return;
261 }
262
263 switch (sig) {
264 case SIGBREAK: {
265 // Check if the signal is a trigger to start the Attach Listener - in that
266 // case don't print stack traces.
267 if (!DisableAttachMechanism && AttachListener::is_init_trigger()) {
268 continue;
269 }
270 // Print stack traces
271 // Any SIGBREAK operations added here should make sure to flush
272 // the output stream (e.g. tty->flush()) after output. See 4803766.
273 // Each module also prints an extra carriage return after its output.
274 VM_PrintThreads op;
275 VMThread::execute(&op);
276 VM_PrintJNI jni_op;
277 VMThread::execute(&jni_op);
278 VM_FindDeadlocks op1(tty);
279 VMThread::execute(&op1);
280 Universe::print_heap_at_SIGBREAK();
281 if (PrintClassHistogram) {
282 VM_GC_HeapInspection op1(tty, true /* force full GC before heap inspection */);
283 VMThread::execute(&op1);
284 }
285 if (JvmtiExport::should_post_data_dump()) {
286 JvmtiExport::post_data_dump();
287 }
288 break;
289 }
290 default: {
291 // Dispatch the signal to java
292 HandleMark hm(THREAD);
293 Klass* k = SystemDictionary::resolve_or_null(vmSymbols::jdk_internal_misc_Signal(), THREAD);
294 KlassHandle klass (THREAD, k);
295 if (klass.not_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() {
351 if (!ReduceSignalUsage) {
352 // Setup JavaThread for processing signals
353 EXCEPTION_MARK;
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 #ifndef ASSERT
653 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
654 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
655 // NMT support
656 void* membase = MemTracker::record_free(memblock);
657 NMT_TrackingLevel level = MemTracker::tracking_level();
658 size_t nmt_header_size = MemTracker::malloc_header_size(level);
659 void* ptr = ::realloc(membase, size + nmt_header_size);
660 return MemTracker::record_malloc(ptr, size, memflags, stack, level);
661 #else
662 if (memblock == NULL) {
663 return os::malloc(size, memflags, stack);
664 }
665 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
666 tty->print_cr("os::realloc caught " PTR_FORMAT, p2i(memblock));
667 breakpoint();
668 }
669 // NMT support
670 void* membase = MemTracker::malloc_base(memblock);
671 verify_memory(membase);
672 if (size == 0) {
673 return NULL;
674 }
675 // always move the block
676 void* ptr = os::malloc(size, memflags, stack);
677 if (PrintMalloc && tty != NULL) {
678 tty->print_cr("os::realloc " SIZE_FORMAT " bytes, " PTR_FORMAT " --> " PTR_FORMAT, size, p2i(memblock), p2i(ptr));
679 }
680 // Copy to new memory if malloc didn't fail
681 if ( ptr != NULL ) {
682 GuardedMemory guarded(MemTracker::malloc_base(memblock));
683 // Guard's user data contains NMT header
684 size_t memblock_size = guarded.get_user_size() - MemTracker::malloc_header_size(memblock);
685 memcpy(ptr, memblock, MIN2(size, memblock_size));
686 if (paranoid) verify_memory(MemTracker::malloc_base(ptr));
687 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) {
688 tty->print_cr("os::realloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr));
689 breakpoint();
690 }
691 os::free(memblock);
692 }
693 return ptr;
694 #endif
695 }
696
697
698 void os::free(void *memblock) {
699 NOT_PRODUCT(inc_stat_counter(&num_frees, 1));
700 #ifdef ASSERT
701 if (memblock == NULL) return;
702 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
703 if (tty != NULL) tty->print_cr("os::free caught " PTR_FORMAT, p2i(memblock));
704 breakpoint();
705 }
706 void* membase = MemTracker::record_free(memblock);
707 verify_memory(membase);
708
709 GuardedMemory guarded(membase);
710 size_t size = guarded.get_user_size();
711 inc_stat_counter(&free_bytes, size);
712 membase = guarded.release_for_freeing();
713 if (PrintMalloc && tty != NULL) {
714 fprintf(stderr, "os::free " SIZE_FORMAT " bytes --> " PTR_FORMAT "\n", size, (uintptr_t)membase);
715 }
716 ::free(membase);
717 #else
718 void* membase = MemTracker::record_free(memblock);
719 ::free(membase);
720 #endif
721 }
722
723 void os::init_random(long initval) {
724 _rand_seed = initval;
725 }
726
727
728 long os::random() {
729 /* standard, well-known linear congruential random generator with
730 * next_rand = (16807*seed) mod (2**31-1)
731 * see
732 * (1) "Random Number Generators: Good Ones Are Hard to Find",
733 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988),
734 * (2) "Two Fast Implementations of the 'Minimal Standard' Random
735 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88.
736 */
737 const long a = 16807;
738 const unsigned long m = 2147483647;
739 const long q = m / a; assert(q == 127773, "weird math");
740 const long r = m % a; assert(r == 2836, "weird math");
741
742 // compute az=2^31p+q
743 unsigned long lo = a * (long)(_rand_seed & 0xFFFF);
744 unsigned long hi = a * (long)((unsigned long)_rand_seed >> 16);
745 lo += (hi & 0x7FFF) << 16;
746
747 // if q overflowed, ignore the overflow and increment q
748 if (lo > m) {
749 lo &= m;
750 ++lo;
751 }
752 lo += hi >> 15;
753
754 // if (p+q) overflowed, ignore the overflow and increment (p+q)
755 if (lo > m) {
756 lo &= m;
757 ++lo;
758 }
759 return (_rand_seed = lo);
760 }
761
762 // The INITIALIZED state is distinguished from the SUSPENDED state because the
763 // conditions in which a thread is first started are different from those in which
764 // a suspension is resumed. These differences make it hard for us to apply the
765 // tougher checks when starting threads that we want to do when resuming them.
766 // However, when start_thread is called as a result of Thread.start, on a Java
767 // thread, the operation is synchronized on the Java Thread object. So there
768 // cannot be a race to start the thread and hence for the thread to exit while
769 // we are working on it. Non-Java threads that start Java threads either have
770 // to do so in a context in which races are impossible, or should do appropriate
771 // locking.
772
773 void os::start_thread(Thread* thread) {
774 // guard suspend/resume
775 MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag);
776 OSThread* osthread = thread->osthread();
777 osthread->set_state(RUNNABLE);
778 pd_start_thread(thread);
779 }
780
781 void os::abort(bool dump_core) {
782 abort(dump_core && CreateCoredumpOnCrash, NULL, NULL);
783 }
784
785 //---------------------------------------------------------------------------
786 // Helper functions for fatal error handler
787
788 void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) {
789 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking");
790
791 int cols = 0;
792 int cols_per_line = 0;
793 switch (unitsize) {
794 case 1: cols_per_line = 16; break;
795 case 2: cols_per_line = 8; break;
796 case 4: cols_per_line = 4; break;
797 case 8: cols_per_line = 2; break;
798 default: return;
799 }
800
801 address p = start;
802 st->print(PTR_FORMAT ": ", p2i(start));
803 while (p < end) {
804 switch (unitsize) {
805 case 1: st->print("%02x", *(u1*)p); break;
806 case 2: st->print("%04x", *(u2*)p); break;
807 case 4: st->print("%08x", *(u4*)p); break;
808 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break;
809 }
810 p += unitsize;
811 cols++;
812 if (cols >= cols_per_line && p < end) {
813 cols = 0;
814 st->cr();
815 st->print(PTR_FORMAT ": ", p2i(p));
816 } else {
817 st->print(" ");
818 }
819 }
820 st->cr();
821 }
822
823 void os::print_environment_variables(outputStream* st, const char** env_list) {
824 if (env_list) {
825 st->print_cr("Environment Variables:");
826
827 for (int i = 0; env_list[i] != NULL; i++) {
828 char *envvar = ::getenv(env_list[i]);
829 if (envvar != NULL) {
830 st->print("%s", env_list[i]);
831 st->print("=");
832 st->print_cr("%s", envvar);
833 }
834 }
835 }
836 }
837
838 void os::print_cpu_info(outputStream* st, char* buf, size_t buflen) {
839 // cpu
840 st->print("CPU:");
841 st->print("total %d", os::processor_count());
842 // It's not safe to query number of active processors after crash
843 // st->print("(active %d)", os::active_processor_count()); but we can
844 // print the initial number of active processors.
845 // We access the raw value here because the assert in the accessor will
846 // fail if the crash occurs before initialization of this value.
847 st->print(" (initial active %d)", _initial_active_processor_count);
848 st->print(" %s", VM_Version::features_string());
849 st->cr();
850 pd_print_cpu_info(st, buf, buflen);
851 }
852
853 // Print a one line string summarizing the cpu, number of cores, memory, and operating system version
854 void os::print_summary_info(outputStream* st, char* buf, size_t buflen) {
855 st->print("Host: ");
856 #ifndef PRODUCT
857 if (get_host_name(buf, buflen)) {
858 st->print("%s, ", buf);
859 }
860 #endif // PRODUCT
861 get_summary_cpu_info(buf, buflen);
862 st->print("%s, ", buf);
863 size_t mem = physical_memory()/G;
864 if (mem == 0) { // for low memory systems
865 mem = physical_memory()/M;
866 st->print("%d cores, " SIZE_FORMAT "M, ", processor_count(), mem);
867 } else {
868 st->print("%d cores, " SIZE_FORMAT "G, ", processor_count(), mem);
869 }
870 get_summary_os_info(buf, buflen);
871 st->print_raw(buf);
872 st->cr();
873 }
874
875 void os::print_date_and_time(outputStream *st, char* buf, size_t buflen) {
876 const int secs_per_day = 86400;
877 const int secs_per_hour = 3600;
878 const int secs_per_min = 60;
879
880 time_t tloc;
881 (void)time(&tloc);
882 char* timestring = ctime(&tloc); // ctime adds newline.
883 // edit out the newline
884 char* nl = strchr(timestring, '\n');
885 if (nl != NULL) {
886 *nl = '\0';
887 }
888
889 struct tm tz;
890 if (localtime_pd(&tloc, &tz) != NULL) {
891 ::strftime(buf, buflen, "%Z", &tz);
892 st->print("Time: %s %s", timestring, buf);
893 } else {
894 st->print("Time: %s", timestring);
895 }
896
897 double t = os::elapsedTime();
898 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in
899 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int
900 // before printf. We lost some precision, but who cares?
901 int eltime = (int)t; // elapsed time in seconds
902
903 // print elapsed time in a human-readable format:
904 int eldays = eltime / secs_per_day;
905 int day_secs = eldays * secs_per_day;
906 int elhours = (eltime - day_secs) / secs_per_hour;
907 int hour_secs = elhours * secs_per_hour;
908 int elmins = (eltime - day_secs - hour_secs) / secs_per_min;
909 int minute_secs = elmins * secs_per_min;
910 int elsecs = (eltime - day_secs - hour_secs - minute_secs);
911 st->print_cr(" elapsed time: %d seconds (%dd %dh %dm %ds)", eltime, eldays, elhours, elmins, elsecs);
912 }
913
914 // moved from debug.cpp (used to be find()) but still called from there
915 // The verbose parameter is only set by the debug code in one case
916 void os::print_location(outputStream* st, intptr_t x, bool verbose) {
917 address addr = (address)x;
918 CodeBlob* b = CodeCache::find_blob_unsafe(addr);
919 if (b != NULL) {
920 if (b->is_buffer_blob()) {
921 // the interpreter is generated into a buffer blob
922 InterpreterCodelet* i = Interpreter::codelet_containing(addr);
923 if (i != NULL) {
924 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an Interpreter codelet", p2i(addr), (int)(addr - i->code_begin()));
925 i->print_on(st);
926 return;
927 }
928 if (Interpreter::contains(addr)) {
929 st->print_cr(INTPTR_FORMAT " is pointing into interpreter code"
930 " (not bytecode specific)", p2i(addr));
931 return;
932 }
933 //
934 if (AdapterHandlerLibrary::contains(b)) {
935 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an AdapterHandler", p2i(addr), (int)(addr - b->code_begin()));
936 AdapterHandlerLibrary::print_handler_on(st, b);
937 }
938 // the stubroutines are generated into a buffer blob
939 StubCodeDesc* d = StubCodeDesc::desc_for(addr);
940 if (d != NULL) {
941 st->print_cr(INTPTR_FORMAT " is at begin+%d in a stub", p2i(addr), (int)(addr - d->begin()));
942 d->print_on(st);
943 st->cr();
944 return;
945 }
946 if (StubRoutines::contains(addr)) {
947 st->print_cr(INTPTR_FORMAT " is pointing to an (unnamed) stub routine", p2i(addr));
948 return;
949 }
950 // the InlineCacheBuffer is using stubs generated into a buffer blob
951 if (InlineCacheBuffer::contains(addr)) {
952 st->print_cr(INTPTR_FORMAT " is pointing into InlineCacheBuffer", p2i(addr));
953 return;
954 }
955 VtableStub* v = VtableStubs::stub_containing(addr);
956 if (v != NULL) {
957 st->print_cr(INTPTR_FORMAT " is at entry_point+%d in a vtable stub", p2i(addr), (int)(addr - v->entry_point()));
958 v->print_on(st);
959 st->cr();
960 return;
961 }
962 }
963 nmethod* nm = b->as_nmethod_or_null();
964 if (nm != NULL) {
965 ResourceMark rm;
966 st->print(INTPTR_FORMAT " is at entry_point+%d in (nmethod*)" INTPTR_FORMAT,
967 p2i(addr), (int)(addr - nm->entry_point()), p2i(nm));
968 if (verbose) {
969 st->print(" for ");
970 nm->method()->print_value_on(st);
971 }
972 st->cr();
973 nm->print_nmethod(verbose);
974 return;
975 }
976 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in ", p2i(addr), (int)(addr - b->code_begin()));
977 b->print_on(st);
978 return;
979 }
980
981 if (Universe::heap()->is_in(addr)) {
982 HeapWord* p = Universe::heap()->block_start(addr);
983 bool print = false;
984 // If we couldn't find it it just may mean that heap wasn't parsable
985 // See if we were just given an oop directly
986 if (p != NULL && Universe::heap()->block_is_obj(p)) {
987 print = true;
988 } else if (p == NULL && ((oopDesc*)addr)->is_oop()) {
989 p = (HeapWord*) addr;
990 print = true;
991 }
992 if (print) {
993 if (p == (HeapWord*) addr) {
994 st->print_cr(INTPTR_FORMAT " is an oop", p2i(addr));
995 } else {
996 st->print_cr(INTPTR_FORMAT " is pointing into object: " INTPTR_FORMAT, p2i(addr), p2i(p));
997 }
998 oop(p)->print_on(st);
999 return;
1000 }
1001 } else {
1002 if (Universe::heap()->is_in_reserved(addr)) {
1003 st->print_cr(INTPTR_FORMAT " is an unallocated location "
1004 "in the heap", p2i(addr));
1005 return;
1006 }
1007 }
1008 if (JNIHandles::is_global_handle((jobject) addr)) {
1009 st->print_cr(INTPTR_FORMAT " is a global jni handle", p2i(addr));
1010 return;
1011 }
1012 if (JNIHandles::is_weak_global_handle((jobject) addr)) {
1013 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", p2i(addr));
1014 return;
1015 }
1016 #ifndef PRODUCT
1017 // we don't keep the block list in product mode
1018 if (JNIHandleBlock::any_contains((jobject) addr)) {
1019 st->print_cr(INTPTR_FORMAT " is a local jni handle", p2i(addr));
1020 return;
1021 }
1022 #endif
1023
1024 for(JavaThread *thread = Threads::first(); thread; thread = thread->next()) {
1025 // Check for privilege stack
1026 if (thread->privileged_stack_top() != NULL &&
1027 thread->privileged_stack_top()->contains(addr)) {
1028 st->print_cr(INTPTR_FORMAT " is pointing into the privilege stack "
1029 "for thread: " INTPTR_FORMAT, p2i(addr), p2i(thread));
1030 if (verbose) thread->print_on(st);
1031 return;
1032 }
1033 // If the addr is a java thread print information about that.
1034 if (addr == (address)thread) {
1035 if (verbose) {
1036 thread->print_on(st);
1037 } else {
1038 st->print_cr(INTPTR_FORMAT " is a thread", p2i(addr));
1039 }
1040 return;
1041 }
1042 // If the addr is in the stack region for this thread then report that
1043 // and print thread info
1044 if (thread->on_local_stack(addr)) {
1045 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: "
1046 INTPTR_FORMAT, p2i(addr), p2i(thread));
1047 if (verbose) thread->print_on(st);
1048 return;
1049 }
1050
1051 }
1052
1053 // Check if in metaspace and print types that have vptrs (only method now)
1054 if (Metaspace::contains(addr)) {
1055 if (Method::has_method_vptr((const void*)addr)) {
1056 ((Method*)addr)->print_value_on(st);
1057 st->cr();
1058 } else {
1059 // Use addr->print() from the debugger instead (not here)
1060 st->print_cr(INTPTR_FORMAT " is pointing into metadata", p2i(addr));
1061 }
1062 return;
1063 }
1064
1065 // Try an OS specific find
1066 if (os::find(addr, st)) {
1067 return;
1068 }
1069
1070 st->print_cr(INTPTR_FORMAT " is an unknown value", p2i(addr));
1071 }
1072
1073 // Looks like all platforms except IA64 can use the same function to check
1074 // if C stack is walkable beyond current frame. The check for fp() is not
1075 // necessary on Sparc, but it's harmless.
1076 bool os::is_first_C_frame(frame* fr) {
1077 #if (defined(IA64) && !defined(AIX)) && !defined(_WIN32)
1078 // On IA64 we have to check if the callers bsp is still valid
1079 // (i.e. within the register stack bounds).
1080 // Notice: this only works for threads created by the VM and only if
1081 // we walk the current stack!!! If we want to be able to walk
1082 // arbitrary other threads, we'll have to somehow store the thread
1083 // object in the frame.
1084 Thread *thread = Thread::current();
1085 if ((address)fr->fp() <=
1086 thread->register_stack_base() HPUX_ONLY(+ 0x0) LINUX_ONLY(+ 0x50)) {
1087 // This check is a little hacky, because on Linux the first C
1088 // frame's ('start_thread') register stack frame starts at
1089 // "register_stack_base + 0x48" while on HPUX, the first C frame's
1090 // ('__pthread_bound_body') register stack frame seems to really
1091 // start at "register_stack_base".
1092 return true;
1093 } else {
1094 return false;
1095 }
1096 #elif defined(IA64) && defined(_WIN32)
1097 return true;
1098 #else
1099 // Load up sp, fp, sender sp and sender fp, check for reasonable values.
1100 // Check usp first, because if that's bad the other accessors may fault
1101 // on some architectures. Ditto ufp second, etc.
1102 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1);
1103 // sp on amd can be 32 bit aligned.
1104 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1);
1105
1106 uintptr_t usp = (uintptr_t)fr->sp();
1107 if ((usp & sp_align_mask) != 0) return true;
1108
1109 uintptr_t ufp = (uintptr_t)fr->fp();
1110 if ((ufp & fp_align_mask) != 0) return true;
1111
1112 uintptr_t old_sp = (uintptr_t)fr->sender_sp();
1113 if ((old_sp & sp_align_mask) != 0) return true;
1114 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true;
1115
1116 uintptr_t old_fp = (uintptr_t)fr->link();
1117 if ((old_fp & fp_align_mask) != 0) return true;
1118 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true;
1119
1120 // stack grows downwards; if old_fp is below current fp or if the stack
1121 // frame is too large, either the stack is corrupted or fp is not saved
1122 // on stack (i.e. on x86, ebp may be used as general register). The stack
1123 // is not walkable beyond current frame.
1124 if (old_fp < ufp) return true;
1125 if (old_fp - ufp > 64 * K) return true;
1126
1127 return false;
1128 #endif
1129 }
1130
1131 #ifdef ASSERT
1132 extern "C" void test_random() {
1133 const double m = 2147483647;
1134 double mean = 0.0, variance = 0.0, t;
1135 long reps = 10000;
1136 unsigned long seed = 1;
1137
1138 tty->print_cr("seed %ld for %ld repeats...", seed, reps);
1139 os::init_random(seed);
1140 long num;
1141 for (int k = 0; k < reps; k++) {
1142 num = os::random();
1143 double u = (double)num / m;
1144 assert(u >= 0.0 && u <= 1.0, "bad random number!");
1145
1146 // calculate mean and variance of the random sequence
1147 mean += u;
1148 variance += (u*u);
1149 }
1150 mean /= reps;
1151 variance /= (reps - 1);
1152
1153 assert(num == 1043618065, "bad seed");
1154 tty->print_cr("mean of the 1st 10000 numbers: %f", mean);
1155 tty->print_cr("variance of the 1st 10000 numbers: %f", variance);
1156 const double eps = 0.0001;
1157 t = fabsd(mean - 0.5018);
1158 assert(t < eps, "bad mean");
1159 t = (variance - 0.3355) < 0.0 ? -(variance - 0.3355) : variance - 0.3355;
1160 assert(t < eps, "bad variance");
1161 }
1162 #endif
1163
1164
1165 // Set up the boot classpath.
1166
1167 char* os::format_boot_path(const char* format_string,
1168 const char* home,
1169 int home_len,
1170 char fileSep,
1171 char pathSep) {
1172 assert((fileSep == '/' && pathSep == ':') ||
1173 (fileSep == '\\' && pathSep == ';'), "unexpected separator chars");
1174
1175 // Scan the format string to determine the length of the actual
1176 // boot classpath, and handle platform dependencies as well.
1177 int formatted_path_len = 0;
1178 const char* p;
1179 for (p = format_string; *p != 0; ++p) {
1180 if (*p == '%') formatted_path_len += home_len - 1;
1181 ++formatted_path_len;
1182 }
1183
1184 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal);
1185 if (formatted_path == NULL) {
1186 return NULL;
1187 }
1188
1189 // Create boot classpath from format, substituting separator chars and
1190 // java home directory.
1191 char* q = formatted_path;
1192 for (p = format_string; *p != 0; ++p) {
1193 switch (*p) {
1194 case '%':
1195 strcpy(q, home);
1196 q += home_len;
1197 break;
1198 case '/':
1199 *q++ = fileSep;
1200 break;
1201 case ':':
1202 *q++ = pathSep;
1203 break;
1204 default:
1205 *q++ = *p;
1206 }
1207 }
1208 *q = '\0';
1209
1210 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched");
1211 return formatted_path;
1212 }
1213
1214 bool os::set_boot_path(char fileSep, char pathSep) {
1215 const char* home = Arguments::get_java_home();
1216 int home_len = (int)strlen(home);
1217
1218 struct stat st;
1219
1220 // modular image if "modules" jimage exists
1221 char* jimage = format_boot_path("%/lib/" MODULES_IMAGE_NAME, home, home_len, fileSep, pathSep);
1222 if (jimage == NULL) return false;
1223 bool has_jimage = (os::stat(jimage, &st) == 0);
1224 if (has_jimage) {
1225 Arguments::set_sysclasspath(jimage, true);
1226 FREE_C_HEAP_ARRAY(char, jimage);
1227 return true;
1228 }
1229 FREE_C_HEAP_ARRAY(char, jimage);
1230
1231 // check if developer build with exploded modules
1232 char* base_classes = format_boot_path("%/modules/java.base", home, home_len, fileSep, pathSep);
1233 if (base_classes == NULL) return false;
1234 if (os::stat(base_classes, &st) == 0) {
1235 Arguments::set_sysclasspath(base_classes, false);
1236 FREE_C_HEAP_ARRAY(char, base_classes);
1237 return true;
1238 }
1239 FREE_C_HEAP_ARRAY(char, base_classes);
1240
1241 return false;
1242 }
1243
1244 /*
1245 * Splits a path, based on its separator, the number of
1246 * elements is returned back in n.
1247 * It is the callers responsibility to:
1248 * a> check the value of n, and n may be 0.
1249 * b> ignore any empty path elements
1250 * c> free up the data.
1251 */
1252 char** os::split_path(const char* path, int* n) {
1253 *n = 0;
1254 if (path == NULL || strlen(path) == 0) {
1255 return NULL;
1256 }
1257 const char psepchar = *os::path_separator();
1258 char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal);
1259 if (inpath == NULL) {
1260 return NULL;
1261 }
1262 strcpy(inpath, path);
1263 int count = 1;
1264 char* p = strchr(inpath, psepchar);
1265 // Get a count of elements to allocate memory
1266 while (p != NULL) {
1267 count++;
1268 p++;
1269 p = strchr(p, psepchar);
1270 }
1271 char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count, mtInternal);
1272 if (opath == NULL) {
1273 return NULL;
1274 }
1275
1276 // do the actual splitting
1277 p = inpath;
1278 for (int i = 0 ; i < count ; i++) {
1279 size_t len = strcspn(p, os::path_separator());
1280 if (len > JVM_MAXPATHLEN) {
1281 return NULL;
1282 }
1283 // allocate the string and add terminator storage
1284 char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
1285 if (s == NULL) {
1286 return NULL;
1287 }
1288 strncpy(s, p, len);
1289 s[len] = '\0';
1290 opath[i] = s;
1291 p += len + 1;
1292 }
1293 FREE_C_HEAP_ARRAY(char, inpath);
1294 *n = count;
1295 return opath;
1296 }
1297
1298 void os::set_memory_serialize_page(address page) {
1299 int count = log2_intptr(sizeof(class JavaThread)) - log2_intptr(64);
1300 _mem_serialize_page = (volatile int32_t *)page;
1301 // We initialize the serialization page shift count here
1302 // We assume a cache line size of 64 bytes
1303 assert(SerializePageShiftCount == count, "JavaThread size changed; "
1304 "SerializePageShiftCount constant should be %d", count);
1305 set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t)));
1306 }
1307
1308 static volatile intptr_t SerializePageLock = 0;
1309
1310 // This method is called from signal handler when SIGSEGV occurs while the current
1311 // thread tries to store to the "read-only" memory serialize page during state
1312 // transition.
1313 void os::block_on_serialize_page_trap() {
1314 log_debug(safepoint)("Block until the serialize page permission restored");
1315
1316 // When VMThread is holding the SerializePageLock during modifying the
1317 // access permission of the memory serialize page, the following call
1318 // will block until the permission of that page is restored to rw.
1319 // Generally, it is unsafe to manipulate locks in signal handlers, but in
1320 // this case, it's OK as the signal is synchronous and we know precisely when
1321 // it can occur.
1322 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page");
1323 Thread::muxRelease(&SerializePageLock);
1324 }
1325
1326 // Serialize all thread state variables
1327 void os::serialize_thread_states() {
1328 // On some platforms such as Solaris & Linux, the time duration of the page
1329 // permission restoration is observed to be much longer than expected due to
1330 // scheduler starvation problem etc. To avoid the long synchronization
1331 // time and expensive page trap spinning, 'SerializePageLock' is used to block
1332 // the mutator thread if such case is encountered. See bug 6546278 for details.
1333 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states");
1334 os::protect_memory((char *)os::get_memory_serialize_page(),
1335 os::vm_page_size(), MEM_PROT_READ);
1336 os::protect_memory((char *)os::get_memory_serialize_page(),
1337 os::vm_page_size(), MEM_PROT_RW);
1338 Thread::muxRelease(&SerializePageLock);
1339 }
1340
1341 // Returns true if the current stack pointer is above the stack shadow
1342 // pages, false otherwise.
1343 bool os::stack_shadow_pages_available(Thread *thread, const methodHandle& method, address sp) {
1344 if (!thread->is_Java_thread()) return false;
1345 // Check if we have StackShadowPages above the yellow zone. This parameter
1346 // is dependent on the depth of the maximum VM call stack possible from
1347 // the handler for stack overflow. 'instanceof' in the stack overflow
1348 // handler or a println uses at least 8k stack of VM and native code
1349 // respectively.
1350 const int framesize_in_bytes =
1351 Interpreter::size_top_interpreter_activation(method()) * wordSize;
1352
1353 address limit = ((JavaThread*)thread)->stack_end() +
1354 (JavaThread::stack_guard_zone_size() + JavaThread::stack_shadow_zone_size());
1355
1356 return sp > (limit + framesize_in_bytes);
1357 }
1358
1359 size_t os::page_size_for_region(size_t region_size, size_t min_pages, bool must_be_aligned) {
1360 assert(min_pages > 0, "sanity");
1361 if (UseLargePages) {
1362 const size_t max_page_size = region_size / min_pages;
1363
1364 for (size_t i = 0; _page_sizes[i] != 0; ++i) {
1365 const size_t page_size = _page_sizes[i];
1366 if (page_size <= max_page_size) {
1367 if (!must_be_aligned || is_size_aligned(region_size, page_size)) {
1368 return page_size;
1369 }
1370 }
1371 }
1372 }
1373
1374 return vm_page_size();
1375 }
1376
1377 size_t os::page_size_for_region_aligned(size_t region_size, size_t min_pages) {
1378 return page_size_for_region(region_size, min_pages, true);
1379 }
1380
1381 size_t os::page_size_for_region_unaligned(size_t region_size, size_t min_pages) {
1382 return page_size_for_region(region_size, min_pages, false);
1383 }
1384
1385 static const char* errno_to_string (int e, bool short_text) {
1386 #define ALL_SHARED_ENUMS(X) \
1387 X(E2BIG, "Argument list too long") \
1388 X(EACCES, "Permission denied") \
1389 X(EADDRINUSE, "Address in use") \
1390 X(EADDRNOTAVAIL, "Address not available") \
1391 X(EAFNOSUPPORT, "Address family not supported") \
1392 X(EAGAIN, "Resource unavailable, try again") \
1393 X(EALREADY, "Connection already in progress") \
1394 X(EBADF, "Bad file descriptor") \
1395 X(EBADMSG, "Bad message") \
1396 X(EBUSY, "Device or resource busy") \
1397 X(ECANCELED, "Operation canceled") \
1398 X(ECHILD, "No child processes") \
1399 X(ECONNABORTED, "Connection aborted") \
1400 X(ECONNREFUSED, "Connection refused") \
1401 X(ECONNRESET, "Connection reset") \
1402 X(EDEADLK, "Resource deadlock would occur") \
1403 X(EDESTADDRREQ, "Destination address required") \
1404 X(EDOM, "Mathematics argument out of domain of function") \
1405 X(EEXIST, "File exists") \
1406 X(EFAULT, "Bad address") \
1407 X(EFBIG, "File too large") \
1408 X(EHOSTUNREACH, "Host is unreachable") \
1409 X(EIDRM, "Identifier removed") \
1410 X(EILSEQ, "Illegal byte sequence") \
1411 X(EINPROGRESS, "Operation in progress") \
1412 X(EINTR, "Interrupted function") \
1413 X(EINVAL, "Invalid argument") \
1414 X(EIO, "I/O error") \
1415 X(EISCONN, "Socket is connected") \
1416 X(EISDIR, "Is a directory") \
1417 X(ELOOP, "Too many levels of symbolic links") \
1418 X(EMFILE, "Too many open files") \
1419 X(EMLINK, "Too many links") \
1420 X(EMSGSIZE, "Message too large") \
1421 X(ENAMETOOLONG, "Filename too long") \
1422 X(ENETDOWN, "Network is down") \
1423 X(ENETRESET, "Connection aborted by network") \
1424 X(ENETUNREACH, "Network unreachable") \
1425 X(ENFILE, "Too many files open in system") \
1426 X(ENOBUFS, "No buffer space available") \
1427 X(ENODATA, "No message is available on the STREAM head read queue") \
1428 X(ENODEV, "No such device") \
1429 X(ENOENT, "No such file or directory") \
1430 X(ENOEXEC, "Executable file format error") \
1431 X(ENOLCK, "No locks available") \
1432 X(ENOLINK, "Reserved") \
1433 X(ENOMEM, "Not enough space") \
1434 X(ENOMSG, "No message of the desired type") \
1435 X(ENOPROTOOPT, "Protocol not available") \
1436 X(ENOSPC, "No space left on device") \
1437 X(ENOSR, "No STREAM resources") \
1438 X(ENOSTR, "Not a STREAM") \
1439 X(ENOSYS, "Function not supported") \
1440 X(ENOTCONN, "The socket is not connected") \
1441 X(ENOTDIR, "Not a directory") \
1442 X(ENOTEMPTY, "Directory not empty") \
1443 X(ENOTSOCK, "Not a socket") \
1444 X(ENOTSUP, "Not supported") \
1445 X(ENOTTY, "Inappropriate I/O control operation") \
1446 X(ENXIO, "No such device or address") \
1447 X(EOPNOTSUPP, "Operation not supported on socket") \
1448 X(EOVERFLOW, "Value too large to be stored in data type") \
1449 X(EPERM, "Operation not permitted") \
1450 X(EPIPE, "Broken pipe") \
1451 X(EPROTO, "Protocol error") \
1452 X(EPROTONOSUPPORT, "Protocol not supported") \
1453 X(EPROTOTYPE, "Protocol wrong type for socket") \
1454 X(ERANGE, "Result too large") \
1455 X(EROFS, "Read-only file system") \
1456 X(ESPIPE, "Invalid seek") \
1457 X(ESRCH, "No such process") \
1458 X(ETIME, "Stream ioctl() timeout") \
1459 X(ETIMEDOUT, "Connection timed out") \
1460 X(ETXTBSY, "Text file busy") \
1461 X(EWOULDBLOCK, "Operation would block") \
1462 X(EXDEV, "Cross-device link")
1463
1464 #define DEFINE_ENTRY(e, text) { e, #e, text },
1465
1466 static const struct {
1467 int v;
1468 const char* short_text;
1469 const char* long_text;
1470 } table [] = {
1471
1472 ALL_SHARED_ENUMS(DEFINE_ENTRY)
1473
1474 // The following enums are not defined on all platforms.
1475 #ifdef ESTALE
1476 DEFINE_ENTRY(ESTALE, "Reserved")
1477 #endif
1478 #ifdef EDQUOT
1479 DEFINE_ENTRY(EDQUOT, "Reserved")
1480 #endif
1481 #ifdef EMULTIHOP
1482 DEFINE_ENTRY(EMULTIHOP, "Reserved")
1483 #endif
1484
1485 // End marker.
1486 { -1, "Unknown errno", "Unknown error" }
1487
1488 };
1489
1490 #undef DEFINE_ENTRY
1491 #undef ALL_FLAGS
1492
1493 int i = 0;
1494 while (table[i].v != -1 && table[i].v != e) {
1495 i ++;
1496 }
1497
1498 return short_text ? table[i].short_text : table[i].long_text;
1499
1500 }
1501
1502 const char* os::strerror(int e) {
1503 return errno_to_string(e, false);
1504 }
1505
1506 const char* os::errno_name(int e) {
1507 return errno_to_string(e, true);
1508 }
1509
1510 void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count) {
1511 LogTarget(Info, pagesize) log;
1512 if (log.is_enabled()) {
1513 LogStreamCHeap out(log);
1514
1515 out.print("%s: ", str);
1516 for (int i = 0; i < count; ++i) {
1517 out.print(" " SIZE_FORMAT, page_sizes[i]);
1518 }
1519 out.cr();
1520 }
1521 }
1522
1523 #define trace_page_size_params(size) byte_size_in_exact_unit(size), exact_unit_for_byte_size(size)
1524
1525 void os::trace_page_sizes(const char* str,
1526 const size_t region_min_size,
1527 const size_t region_max_size,
1528 const size_t page_size,
1529 const char* base,
1530 const size_t size) {
1531
1532 log_info(pagesize)("%s: "
1533 " min=" SIZE_FORMAT "%s"
1534 " max=" SIZE_FORMAT "%s"
1535 " base=" PTR_FORMAT
1536 " page_size=" SIZE_FORMAT "%s"
1537 " size=" SIZE_FORMAT "%s",
1538 str,
1539 trace_page_size_params(region_min_size),
1540 trace_page_size_params(region_max_size),
1541 p2i(base),
1542 trace_page_size_params(page_size),
1543 trace_page_size_params(size));
1544 }
1545
1546 void os::trace_page_sizes_for_requested_size(const char* str,
1547 const size_t requested_size,
1548 const size_t page_size,
1549 const size_t alignment,
1550 const char* base,
1551 const size_t size) {
1552
1553 log_info(pagesize)("%s:"
1554 " req_size=" SIZE_FORMAT "%s"
1555 " base=" PTR_FORMAT
1556 " page_size=" SIZE_FORMAT "%s"
1557 " alignment=" SIZE_FORMAT "%s"
1558 " size=" SIZE_FORMAT "%s",
1559 str,
1560 trace_page_size_params(requested_size),
1561 p2i(base),
1562 trace_page_size_params(page_size),
1563 trace_page_size_params(alignment),
1564 trace_page_size_params(size));
1565 }
1566
1567
1568 // This is the working definition of a server class machine:
1569 // >= 2 physical CPU's and >=2GB of memory, with some fuzz
1570 // because the graphics memory (?) sometimes masks physical memory.
1571 // If you want to change the definition of a server class machine
1572 // on some OS or platform, e.g., >=4GB on Windows platforms,
1573 // then you'll have to parameterize this method based on that state,
1574 // as was done for logical processors here, or replicate and
1575 // specialize this method for each platform. (Or fix os to have
1576 // some inheritance structure and use subclassing. Sigh.)
1577 // If you want some platform to always or never behave as a server
1578 // class machine, change the setting of AlwaysActAsServerClassMachine
1579 // and NeverActAsServerClassMachine in globals*.hpp.
1580 bool os::is_server_class_machine() {
1581 // First check for the early returns
1582 if (NeverActAsServerClassMachine) {
1583 return false;
1584 }
1585 if (AlwaysActAsServerClassMachine) {
1586 return true;
1587 }
1588 // Then actually look at the machine
1589 bool result = false;
1590 const unsigned int server_processors = 2;
1591 const julong server_memory = 2UL * G;
1592 // We seem not to get our full complement of memory.
1593 // We allow some part (1/8?) of the memory to be "missing",
1594 // based on the sizes of DIMMs, and maybe graphics cards.
1595 const julong missing_memory = 256UL * M;
1596
1597 /* Is this a server class machine? */
1598 if ((os::active_processor_count() >= (int)server_processors) &&
1599 (os::physical_memory() >= (server_memory - missing_memory))) {
1600 const unsigned int logical_processors =
1601 VM_Version::logical_processors_per_package();
1602 if (logical_processors > 1) {
1603 const unsigned int physical_packages =
1604 os::active_processor_count() / logical_processors;
1605 if (physical_packages >= server_processors) {
1606 result = true;
1607 }
1608 } else {
1609 result = true;
1610 }
1611 }
1612 return result;
1613 }
1614
1615 void os::initialize_initial_active_processor_count() {
1616 assert(_initial_active_processor_count == 0, "Initial active processor count already set.");
1617 _initial_active_processor_count = active_processor_count();
1618 log_debug(os)("Initial active processor count set to %d" , _initial_active_processor_count);
1619 }
1620
1621 void os::SuspendedThreadTask::run() {
1622 assert(Threads_lock->owned_by_self() || (_thread == VMThread::vm_thread()), "must have threads lock to call this");
1623 internal_do_task();
1624 _done = true;
1625 }
1626
1627 bool os::create_stack_guard_pages(char* addr, size_t bytes) {
1628 return os::pd_create_stack_guard_pages(addr, bytes);
1629 }
1630
1631 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint) {
1632 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1633 if (result != NULL) {
1634 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1635 }
1636
1637 return result;
1638 }
1639
1640 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint,
1641 MEMFLAGS flags) {
1642 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1643 if (result != NULL) {
1644 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1645 MemTracker::record_virtual_memory_type((address)result, flags);
1646 }
1647
1648 return result;
1649 }
1650
1651 char* os::attempt_reserve_memory_at(size_t bytes, char* addr) {
1652 char* result = pd_attempt_reserve_memory_at(bytes, addr);
1653 if (result != NULL) {
1654 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1655 }
1656 return result;
1657 }
1658
1659 void os::split_reserved_memory(char *base, size_t size,
1660 size_t split, bool realloc) {
1661 pd_split_reserved_memory(base, size, split, realloc);
1662 }
1663
1664 bool os::commit_memory(char* addr, size_t bytes, bool executable) {
1665 bool res = pd_commit_memory(addr, bytes, executable);
1666 if (res) {
1667 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1668 }
1669 return res;
1670 }
1671
1672 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint,
1673 bool executable) {
1674 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable);
1675 if (res) {
1676 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1677 }
1678 return res;
1679 }
1680
1681 void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable,
1682 const char* mesg) {
1683 pd_commit_memory_or_exit(addr, bytes, executable, mesg);
1684 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1685 }
1686
1687 void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint,
1688 bool executable, const char* mesg) {
1689 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg);
1690 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1691 }
1692
1693 bool os::uncommit_memory(char* addr, size_t bytes) {
1694 bool res;
1695 if (MemTracker::tracking_level() > NMT_minimal) {
1696 Tracker tkr = MemTracker::get_virtual_memory_uncommit_tracker();
1697 res = pd_uncommit_memory(addr, bytes);
1698 if (res) {
1699 tkr.record((address)addr, bytes);
1700 }
1701 } else {
1702 res = pd_uncommit_memory(addr, bytes);
1703 }
1704 return res;
1705 }
1706
1707 bool os::release_memory(char* addr, size_t bytes) {
1708 bool res;
1709 if (MemTracker::tracking_level() > NMT_minimal) {
1710 Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
1711 res = pd_release_memory(addr, bytes);
1712 if (res) {
1713 tkr.record((address)addr, bytes);
1714 }
1715 } else {
1716 res = pd_release_memory(addr, bytes);
1717 }
1718 return res;
1719 }
1720
1721 void os::pretouch_memory(void* start, void* end, size_t page_size) {
1722 for (volatile char *p = (char*)start; p < (char*)end; p += page_size) {
1723 *p = 0;
1724 }
1725 }
1726
1727 char* os::map_memory(int fd, const char* file_name, size_t file_offset,
1728 char *addr, size_t bytes, bool read_only,
1729 bool allow_exec) {
1730 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec);
1731 if (result != NULL) {
1732 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC);
1733 }
1734 return result;
1735 }
1736
1737 char* os::remap_memory(int fd, const char* file_name, size_t file_offset,
1738 char *addr, size_t bytes, bool read_only,
1739 bool allow_exec) {
1740 return pd_remap_memory(fd, file_name, file_offset, addr, bytes,
1741 read_only, allow_exec);
1742 }
1743
1744 bool os::unmap_memory(char *addr, size_t bytes) {
1745 bool result;
1746 if (MemTracker::tracking_level() > NMT_minimal) {
1747 Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
1748 result = pd_unmap_memory(addr, bytes);
1749 if (result) {
1750 tkr.record((address)addr, bytes);
1751 }
1752 } else {
1753 result = pd_unmap_memory(addr, bytes);
1754 }
1755 return result;
1756 }
1757
1758 void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) {
1759 pd_free_memory(addr, bytes, alignment_hint);
1760 }
1761
1762 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
1763 pd_realign_memory(addr, bytes, alignment_hint);
1764 }
1765
1766 #ifndef _WINDOWS
1767 /* try to switch state from state "from" to state "to"
1768 * returns the state set after the method is complete
1769 */
1770 os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from,
1771 os::SuspendResume::State to)
1772 {
1773 os::SuspendResume::State result =
1774 (os::SuspendResume::State) Atomic::cmpxchg((jint) to, (jint *) &_state, (jint) from);
1775 if (result == from) {
1776 // success
1777 return to;
1778 }
1779 return result;
1780 }
1781 #endif