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.inline.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 size_t os::_page_sizes[os::page_sizes_max];
75
76 #ifndef PRODUCT
77 julong os::num_mallocs = 0; // # of calls to malloc/realloc
78 julong os::alloc_bytes = 0; // # of bytes allocated
79 julong os::num_frees = 0; // # of calls to free
80 julong os::free_bytes = 0; // # of bytes freed
81 #endif
82
83 static juint cur_malloc_words = 0; // current size for MallocMaxTestWords
84
85 void os_init_globals() {
86 // Called from init_globals().
87 // See Threads::create_vm() in thread.cpp, and init.cpp.
88 os::init_globals();
89 }
90
91 // Fill in buffer with current local time as an ISO-8601 string.
92 // E.g., yyyy-mm-ddThh:mm:ss-zzzz.
93 // Returns buffer, or NULL if it failed.
94 // This would mostly be a call to
95 // strftime(...., "%Y-%m-%d" "T" "%H:%M:%S" "%z", ....)
96 // except that on Windows the %z behaves badly, so we do it ourselves.
97 // Also, people wanted milliseconds on there,
98 // and strftime doesn't do milliseconds.
99 char* os::iso8601_time(char* buffer, size_t buffer_length) {
100 // Output will be of the form "YYYY-MM-DDThh:mm:ss.mmm+zzzz\0"
101 // 1 2
102 // 12345678901234567890123456789
103 // format string: "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d"
104 static const size_t needed_buffer = 29;
105
106 // Sanity check the arguments
107 if (buffer == NULL) {
108 assert(false, "NULL buffer");
109 return NULL;
110 }
111 if (buffer_length < needed_buffer) {
112 assert(false, "buffer_length too small");
113 return NULL;
114 }
115 // Get the current time
116 jlong milliseconds_since_19700101 = javaTimeMillis();
117 const int milliseconds_per_microsecond = 1000;
118 const time_t seconds_since_19700101 =
119 milliseconds_since_19700101 / milliseconds_per_microsecond;
120 const int milliseconds_after_second =
121 milliseconds_since_19700101 % milliseconds_per_microsecond;
122 // Convert the time value to a tm and timezone variable
123 struct tm time_struct;
124 if (localtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
125 assert(false, "Failed localtime_pd");
126 return NULL;
127 }
128 #if defined(_ALLBSD_SOURCE)
129 const time_t zone = (time_t) time_struct.tm_gmtoff;
130 #else
131 const time_t zone = timezone;
132 #endif
133
134 // If daylight savings time is in effect,
135 // we are 1 hour East of our time zone
136 const time_t seconds_per_minute = 60;
137 const time_t minutes_per_hour = 60;
138 const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour;
139 time_t UTC_to_local = zone;
140 if (time_struct.tm_isdst > 0) {
141 UTC_to_local = UTC_to_local - seconds_per_hour;
142 }
143 // Compute the time zone offset.
144 // localtime_pd() sets timezone to the difference (in seconds)
145 // between UTC and and local time.
146 // ISO 8601 says we need the difference between local time and UTC,
147 // we change the sign of the localtime_pd() result.
148 const time_t local_to_UTC = -(UTC_to_local);
149 // Then we have to figure out if if we are ahead (+) or behind (-) UTC.
150 char sign_local_to_UTC = '+';
151 time_t abs_local_to_UTC = local_to_UTC;
152 if (local_to_UTC < 0) {
153 sign_local_to_UTC = '-';
154 abs_local_to_UTC = -(abs_local_to_UTC);
155 }
156 // Convert time zone offset seconds to hours and minutes.
157 const time_t zone_hours = (abs_local_to_UTC / seconds_per_hour);
158 const time_t zone_min =
159 ((abs_local_to_UTC % seconds_per_hour) / seconds_per_minute);
160
161 // Print an ISO 8601 date and time stamp into the buffer
162 const int year = 1900 + time_struct.tm_year;
163 const int month = 1 + time_struct.tm_mon;
164 const int printed = jio_snprintf(buffer, buffer_length,
165 "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d",
166 year,
167 month,
168 time_struct.tm_mday,
169 time_struct.tm_hour,
170 time_struct.tm_min,
171 time_struct.tm_sec,
172 milliseconds_after_second,
173 sign_local_to_UTC,
174 zone_hours,
175 zone_min);
176 if (printed == 0) {
177 assert(false, "Failed jio_printf");
178 return NULL;
179 }
180 return buffer;
181 }
182
183 OSReturn os::set_priority(Thread* thread, ThreadPriority p) {
184 #ifdef ASSERT
185 if (!(!thread->is_Java_thread() ||
186 Thread::current() == thread ||
187 Threads_lock->owned_by_self()
188 || thread->is_Compiler_thread()
189 )) {
190 assert(false, "possibility of dangling Thread pointer");
191 }
192 #endif
193
194 if (p >= MinPriority && p <= MaxPriority) {
195 int priority = java_to_os_priority[p];
196 return set_native_priority(thread, priority);
197 } else {
198 assert(false, "Should not happen");
199 return OS_ERR;
200 }
201 }
202
203 // The mapping from OS priority back to Java priority may be inexact because
204 // Java priorities can map M:1 with native priorities. If you want the definite
205 // Java priority then use JavaThread::java_priority()
206 OSReturn os::get_priority(const Thread* const thread, ThreadPriority& priority) {
207 int p;
208 int os_prio;
209 OSReturn ret = get_native_priority(thread, &os_prio);
210 if (ret != OS_OK) return ret;
211
212 if (java_to_os_priority[MaxPriority] > java_to_os_priority[MinPriority]) {
213 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] > os_prio; p--) ;
214 } else {
215 // niceness values are in reverse order
216 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] < os_prio; p--) ;
217 }
218 priority = (ThreadPriority)p;
219 return OS_OK;
220 }
221
222
223 // --------------------- sun.misc.Signal (optional) ---------------------
224
225
226 // SIGBREAK is sent by the keyboard to query the VM state
227 #ifndef SIGBREAK
228 #define SIGBREAK SIGQUIT
229 #endif
230
231 // sigexitnum_pd is a platform-specific special signal used for terminating the Signal thread.
232
233
234 static void signal_thread_entry(JavaThread* thread, TRAPS) {
235 os::set_priority(thread, NearMaxPriority);
236 while (true) {
237 int sig;
238 {
239 // FIXME : Currently we have not decided what should be the status
240 // for this java thread blocked here. Once we decide about
241 // that we should fix this.
242 sig = os::signal_wait();
243 }
244 if (sig == os::sigexitnum_pd()) {
245 // Terminate the signal thread
246 return;
247 }
248
249 switch (sig) {
250 case SIGBREAK: {
251 // Check if the signal is a trigger to start the Attach Listener - in that
252 // case don't print stack traces.
253 if (!DisableAttachMechanism && AttachListener::is_init_trigger()) {
254 continue;
255 }
256 // Print stack traces
257 // Any SIGBREAK operations added here should make sure to flush
258 // the output stream (e.g. tty->flush()) after output. See 4803766.
259 // Each module also prints an extra carriage return after its output.
260 VM_PrintThreads op;
261 VMThread::execute(&op);
262 VM_PrintJNI jni_op;
263 VMThread::execute(&jni_op);
264 VM_FindDeadlocks op1(tty);
265 VMThread::execute(&op1);
266 Universe::print_heap_at_SIGBREAK();
267 if (PrintClassHistogram) {
268 VM_GC_HeapInspection op1(tty, true /* force full GC before heap inspection */);
269 VMThread::execute(&op1);
270 }
271 if (JvmtiExport::should_post_data_dump()) {
272 JvmtiExport::post_data_dump();
273 }
274 break;
275 }
276 default: {
277 // Dispatch the signal to java
278 HandleMark hm(THREAD);
279 Klass* k = SystemDictionary::resolve_or_null(vmSymbols::jdk_internal_misc_Signal(), THREAD);
280 KlassHandle klass (THREAD, k);
281 if (klass.not_null()) {
282 JavaValue result(T_VOID);
283 JavaCallArguments args;
284 args.push_int(sig);
285 JavaCalls::call_static(
286 &result,
287 klass,
288 vmSymbols::dispatch_name(),
289 vmSymbols::int_void_signature(),
290 &args,
291 THREAD
292 );
293 }
294 if (HAS_PENDING_EXCEPTION) {
295 // tty is initialized early so we don't expect it to be null, but
296 // if it is we can't risk doing an initialization that might
297 // trigger additional out-of-memory conditions
298 if (tty != NULL) {
299 char klass_name[256];
300 char tmp_sig_name[16];
301 const char* sig_name = "UNKNOWN";
302 InstanceKlass::cast(PENDING_EXCEPTION->klass())->
303 name()->as_klass_external_name(klass_name, 256);
304 if (os::exception_name(sig, tmp_sig_name, 16) != NULL)
305 sig_name = tmp_sig_name;
306 warning("Exception %s occurred dispatching signal %s to handler"
307 "- the VM may need to be forcibly terminated",
308 klass_name, sig_name );
309 }
310 CLEAR_PENDING_EXCEPTION;
311 }
312 }
313 }
314 }
315 }
316
317 void os::init_before_ergo() {
318 // We need to initialize large page support here because ergonomics takes some
319 // decisions depending on large page support and the calculated large page size.
320 large_page_init();
321
322 // We need to adapt the configured number of stack protection pages given
323 // in 4K pages to the actual os page size. We must do this before setting
324 // up minimal stack sizes etc. in os::init_2().
325 JavaThread::set_stack_red_zone_size (align_size_up(StackRedPages * 4 * K, vm_page_size()));
326 JavaThread::set_stack_yellow_zone_size (align_size_up(StackYellowPages * 4 * K, vm_page_size()));
327 JavaThread::set_stack_reserved_zone_size(align_size_up(StackReservedPages * 4 * K, vm_page_size()));
328 JavaThread::set_stack_shadow_zone_size (align_size_up(StackShadowPages * 4 * K, vm_page_size()));
329
330 // VM version initialization identifies some characteristics of the
331 // platform that are used during ergonomic decisions.
332 VM_Version::init_before_ergo();
333 }
334
335 void os::signal_init() {
336 if (!ReduceSignalUsage) {
337 // Setup JavaThread for processing signals
338 EXCEPTION_MARK;
339 Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(), true, CHECK);
340 instanceKlassHandle klass (THREAD, k);
341 instanceHandle thread_oop = klass->allocate_instance_handle(CHECK);
342
343 const char thread_name[] = "Signal Dispatcher";
344 Handle string = java_lang_String::create_from_str(thread_name, CHECK);
345
346 // Initialize thread_oop to put it into the system threadGroup
347 Handle thread_group (THREAD, Universe::system_thread_group());
348 JavaValue result(T_VOID);
349 JavaCalls::call_special(&result, thread_oop,
350 klass,
351 vmSymbols::object_initializer_name(),
352 vmSymbols::threadgroup_string_void_signature(),
353 thread_group,
354 string,
355 CHECK);
356
357 KlassHandle group(THREAD, SystemDictionary::ThreadGroup_klass());
358 JavaCalls::call_special(&result,
359 thread_group,
360 group,
361 vmSymbols::add_method_name(),
362 vmSymbols::thread_void_signature(),
363 thread_oop, // ARG 1
364 CHECK);
365
366 os::signal_init_pd();
367
368 { MutexLocker mu(Threads_lock);
369 JavaThread* signal_thread = new JavaThread(&signal_thread_entry);
370
371 // At this point it may be possible that no osthread was created for the
372 // JavaThread due to lack of memory. We would have to throw an exception
373 // in that case. However, since this must work and we do not allow
374 // exceptions anyway, check and abort if this fails.
375 if (signal_thread == NULL || signal_thread->osthread() == NULL) {
376 vm_exit_during_initialization("java.lang.OutOfMemoryError",
377 os::native_thread_creation_failed_msg());
378 }
379
380 java_lang_Thread::set_thread(thread_oop(), signal_thread);
381 java_lang_Thread::set_priority(thread_oop(), NearMaxPriority);
382 java_lang_Thread::set_daemon(thread_oop());
383
384 signal_thread->set_threadObj(thread_oop());
385 Threads::add(signal_thread);
386 Thread::start(signal_thread);
387 }
388 // Handle ^BREAK
389 os::signal(SIGBREAK, os::user_handler());
390 }
391 }
392
393
394 void os::terminate_signal_thread() {
395 if (!ReduceSignalUsage)
396 signal_notify(sigexitnum_pd());
397 }
398
399
400 // --------------------- loading libraries ---------------------
401
402 typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *);
403 extern struct JavaVM_ main_vm;
404
405 static void* _native_java_library = NULL;
406
407 void* os::native_java_library() {
408 if (_native_java_library == NULL) {
409 char buffer[JVM_MAXPATHLEN];
410 char ebuf[1024];
411
412 // Try to load verify dll first. In 1.3 java dll depends on it and is not
413 // always able to find it when the loading executable is outside the JDK.
414 // In order to keep working with 1.2 we ignore any loading errors.
415 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
416 "verify")) {
417 dll_load(buffer, ebuf, sizeof(ebuf));
418 }
419
420 // Load java dll
421 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
422 "java")) {
423 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf));
424 }
425 if (_native_java_library == NULL) {
426 vm_exit_during_initialization("Unable to load native library", ebuf);
427 }
428
429 #if defined(__OpenBSD__)
430 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so
431 // ignore errors
432 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
433 "net")) {
434 dll_load(buffer, ebuf, sizeof(ebuf));
435 }
436 #endif
437 }
438 return _native_java_library;
439 }
440
441 /*
442 * Support for finding Agent_On(Un)Load/Attach<_lib_name> if it exists.
443 * If check_lib == true then we are looking for an
444 * Agent_OnLoad_lib_name or Agent_OnAttach_lib_name function to determine if
445 * this library is statically linked into the image.
446 * If check_lib == false then we will look for the appropriate symbol in the
447 * executable if agent_lib->is_static_lib() == true or in the shared library
448 * referenced by 'handle'.
449 */
450 void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib,
451 const char *syms[], size_t syms_len) {
452 assert(agent_lib != NULL, "sanity check");
453 const char *lib_name;
454 void *handle = agent_lib->os_lib();
455 void *entryName = NULL;
456 char *agent_function_name;
457 size_t i;
458
459 // If checking then use the agent name otherwise test is_static_lib() to
460 // see how to process this lookup
461 lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL);
462 for (i = 0; i < syms_len; i++) {
463 agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path());
464 if (agent_function_name == NULL) {
465 break;
466 }
467 entryName = dll_lookup(handle, agent_function_name);
468 FREE_C_HEAP_ARRAY(char, agent_function_name);
469 if (entryName != NULL) {
470 break;
471 }
472 }
473 return entryName;
474 }
475
476 // See if the passed in agent is statically linked into the VM image.
477 bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
478 size_t syms_len) {
479 void *ret;
480 void *proc_handle;
481 void *save_handle;
482
483 assert(agent_lib != NULL, "sanity check");
484 if (agent_lib->name() == NULL) {
485 return false;
486 }
487 proc_handle = get_default_process_handle();
488 // Check for Agent_OnLoad/Attach_lib_name function
489 save_handle = agent_lib->os_lib();
490 // We want to look in this process' symbol table.
491 agent_lib->set_os_lib(proc_handle);
492 ret = find_agent_function(agent_lib, true, syms, syms_len);
493 if (ret != NULL) {
494 // Found an entry point like Agent_OnLoad_lib_name so we have a static agent
495 agent_lib->set_valid();
496 agent_lib->set_static_lib(true);
497 return true;
498 }
499 agent_lib->set_os_lib(save_handle);
500 return false;
501 }
502
503 // --------------------- heap allocation utilities ---------------------
504
505 char *os::strdup(const char *str, MEMFLAGS flags) {
506 size_t size = strlen(str);
507 char *dup_str = (char *)malloc(size + 1, flags);
508 if (dup_str == NULL) return NULL;
509 strcpy(dup_str, str);
510 return dup_str;
511 }
512
513 char* os::strdup_check_oom(const char* str, MEMFLAGS flags) {
514 char* p = os::strdup(str, flags);
515 if (p == NULL) {
516 vm_exit_out_of_memory(strlen(str) + 1, OOM_MALLOC_ERROR, "os::strdup_check_oom");
517 }
518 return p;
519 }
520
521
522 #define paranoid 0 /* only set to 1 if you suspect checking code has bug */
523
524 #ifdef ASSERT
525
526 static void verify_memory(void* ptr) {
527 GuardedMemory guarded(ptr);
528 if (!guarded.verify_guards()) {
529 tty->print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees);
530 tty->print_cr("## memory stomp:");
531 guarded.print_on(tty);
532 fatal("memory stomping error");
533 }
534 }
535
536 #endif
537
538 //
539 // This function supports testing of the malloc out of memory
540 // condition without really running the system out of memory.
541 //
542 static bool has_reached_max_malloc_test_peak(size_t alloc_size) {
543 if (MallocMaxTestWords > 0) {
544 jint words = (jint)(alloc_size / BytesPerWord);
545
546 if ((cur_malloc_words + words) > MallocMaxTestWords) {
547 return true;
548 }
549 Atomic::add(words, (volatile jint *)&cur_malloc_words);
550 }
551 return false;
552 }
553
554 void* os::malloc(size_t size, MEMFLAGS flags) {
555 return os::malloc(size, flags, CALLER_PC);
556 }
557
558 void* os::malloc(size_t size, MEMFLAGS memflags, const NativeCallStack& stack) {
559 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
560 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
561
562 #ifdef ASSERT
563 // checking for the WatcherThread and crash_protection first
564 // since os::malloc can be called when the libjvm.{dll,so} is
565 // first loaded and we don't have a thread yet.
566 // try to find the thread after we see that the watcher thread
567 // exists and has crash protection.
568 WatcherThread *wt = WatcherThread::watcher_thread();
569 if (wt != NULL && wt->has_crash_protection()) {
570 Thread* thread = Thread::current_or_null();
571 if (thread == wt) {
572 assert(!wt->has_crash_protection(),
573 "Can't malloc with crash protection from WatcherThread");
574 }
575 }
576 #endif
577
578 if (size == 0) {
579 // return a valid pointer if size is zero
580 // if NULL is returned the calling functions assume out of memory.
581 size = 1;
582 }
583
584 // NMT support
585 NMT_TrackingLevel level = MemTracker::tracking_level();
586 size_t nmt_header_size = MemTracker::malloc_header_size(level);
587
588 #ifndef ASSERT
589 const size_t alloc_size = size + nmt_header_size;
590 #else
591 const size_t alloc_size = GuardedMemory::get_total_size(size + nmt_header_size);
592 if (size + nmt_header_size > alloc_size) { // Check for rollover.
593 return NULL;
594 }
595 #endif
596
597 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
598
599 // For the test flag -XX:MallocMaxTestWords
600 if (has_reached_max_malloc_test_peak(size)) {
601 return NULL;
602 }
603
604 u_char* ptr;
605 ptr = (u_char*)::malloc(alloc_size);
606
607 #ifdef ASSERT
608 if (ptr == NULL) {
609 return NULL;
610 }
611 // Wrap memory with guard
612 GuardedMemory guarded(ptr, size + nmt_header_size);
613 ptr = guarded.get_user_ptr();
614 #endif
615 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) {
616 tty->print_cr("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr));
617 breakpoint();
618 }
619 debug_only(if (paranoid) verify_memory(ptr));
620 if (PrintMalloc && tty != NULL) {
621 tty->print_cr("os::malloc " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr));
622 }
623
624 // we do not track guard memory
625 return MemTracker::record_malloc((address)ptr, size, memflags, stack, level);
626 }
627
628 void* os::realloc(void *memblock, size_t size, MEMFLAGS flags) {
629 return os::realloc(memblock, size, flags, CALLER_PC);
630 }
631
632 void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, const NativeCallStack& stack) {
633
634 // For the test flag -XX:MallocMaxTestWords
635 if (has_reached_max_malloc_test_peak(size)) {
636 return NULL;
637 }
638
639 #ifndef ASSERT
640 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
641 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
642 // NMT support
643 void* membase = MemTracker::record_free(memblock);
644 NMT_TrackingLevel level = MemTracker::tracking_level();
645 size_t nmt_header_size = MemTracker::malloc_header_size(level);
646 void* ptr = ::realloc(membase, size + nmt_header_size);
647 return MemTracker::record_malloc(ptr, size, memflags, stack, level);
648 #else
649 if (memblock == NULL) {
650 return os::malloc(size, memflags, stack);
651 }
652 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
653 tty->print_cr("os::realloc caught " PTR_FORMAT, p2i(memblock));
654 breakpoint();
655 }
656 // NMT support
657 void* membase = MemTracker::malloc_base(memblock);
658 verify_memory(membase);
659 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
660 if (size == 0) {
661 return NULL;
662 }
663 // always move the block
664 void* ptr = os::malloc(size, memflags, stack);
665 if (PrintMalloc && tty != NULL) {
666 tty->print_cr("os::realloc " SIZE_FORMAT " bytes, " PTR_FORMAT " --> " PTR_FORMAT, size, p2i(memblock), p2i(ptr));
667 }
668 // Copy to new memory if malloc didn't fail
669 if ( ptr != NULL ) {
670 GuardedMemory guarded(MemTracker::malloc_base(memblock));
671 // Guard's user data contains NMT header
672 size_t memblock_size = guarded.get_user_size() - MemTracker::malloc_header_size(memblock);
673 memcpy(ptr, memblock, MIN2(size, memblock_size));
674 if (paranoid) verify_memory(MemTracker::malloc_base(ptr));
675 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) {
676 tty->print_cr("os::realloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr));
677 breakpoint();
678 }
679 os::free(memblock);
680 }
681 return ptr;
682 #endif
683 }
684
685
686 void os::free(void *memblock) {
687 NOT_PRODUCT(inc_stat_counter(&num_frees, 1));
688 #ifdef ASSERT
689 if (memblock == NULL) return;
690 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
691 if (tty != NULL) tty->print_cr("os::free caught " PTR_FORMAT, p2i(memblock));
692 breakpoint();
693 }
694 void* membase = MemTracker::record_free(memblock);
695 verify_memory(membase);
696 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
697
698 GuardedMemory guarded(membase);
699 size_t size = guarded.get_user_size();
700 inc_stat_counter(&free_bytes, size);
701 membase = guarded.release_for_freeing();
702 if (PrintMalloc && tty != NULL) {
703 fprintf(stderr, "os::free " SIZE_FORMAT " bytes --> " PTR_FORMAT "\n", size, (uintptr_t)membase);
704 }
705 ::free(membase);
706 #else
707 void* membase = MemTracker::record_free(memblock);
708 ::free(membase);
709 #endif
710 }
711
712 void os::init_random(long initval) {
713 _rand_seed = initval;
714 }
715
716
717 long os::random() {
718 /* standard, well-known linear congruential random generator with
719 * next_rand = (16807*seed) mod (2**31-1)
720 * see
721 * (1) "Random Number Generators: Good Ones Are Hard to Find",
722 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988),
723 * (2) "Two Fast Implementations of the 'Minimal Standard' Random
724 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88.
725 */
726 const long a = 16807;
727 const unsigned long m = 2147483647;
728 const long q = m / a; assert(q == 127773, "weird math");
729 const long r = m % a; assert(r == 2836, "weird math");
730
731 // compute az=2^31p+q
732 unsigned long lo = a * (long)(_rand_seed & 0xFFFF);
733 unsigned long hi = a * (long)((unsigned long)_rand_seed >> 16);
734 lo += (hi & 0x7FFF) << 16;
735
736 // if q overflowed, ignore the overflow and increment q
737 if (lo > m) {
738 lo &= m;
739 ++lo;
740 }
741 lo += hi >> 15;
742
743 // if (p+q) overflowed, ignore the overflow and increment (p+q)
744 if (lo > m) {
745 lo &= m;
746 ++lo;
747 }
748 return (_rand_seed = lo);
749 }
750
751 // The INITIALIZED state is distinguished from the SUSPENDED state because the
752 // conditions in which a thread is first started are different from those in which
753 // a suspension is resumed. These differences make it hard for us to apply the
754 // tougher checks when starting threads that we want to do when resuming them.
755 // However, when start_thread is called as a result of Thread.start, on a Java
756 // thread, the operation is synchronized on the Java Thread object. So there
757 // cannot be a race to start the thread and hence for the thread to exit while
758 // we are working on it. Non-Java threads that start Java threads either have
759 // to do so in a context in which races are impossible, or should do appropriate
760 // locking.
761
762 void os::start_thread(Thread* thread) {
763 // guard suspend/resume
764 MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag);
765 OSThread* osthread = thread->osthread();
766 osthread->set_state(RUNNABLE);
767 pd_start_thread(thread);
768 }
769
770 void os::abort(bool dump_core) {
771 abort(dump_core && CreateCoredumpOnCrash, NULL, NULL);
772 }
773
774 //---------------------------------------------------------------------------
775 // Helper functions for fatal error handler
776
777 void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) {
778 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking");
779
780 int cols = 0;
781 int cols_per_line = 0;
782 switch (unitsize) {
783 case 1: cols_per_line = 16; break;
784 case 2: cols_per_line = 8; break;
785 case 4: cols_per_line = 4; break;
786 case 8: cols_per_line = 2; break;
787 default: return;
788 }
789
790 address p = start;
791 st->print(PTR_FORMAT ": ", p2i(start));
792 while (p < end) {
793 switch (unitsize) {
794 case 1: st->print("%02x", *(u1*)p); break;
795 case 2: st->print("%04x", *(u2*)p); break;
796 case 4: st->print("%08x", *(u4*)p); break;
797 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break;
798 }
799 p += unitsize;
800 cols++;
801 if (cols >= cols_per_line && p < end) {
802 cols = 0;
803 st->cr();
804 st->print(PTR_FORMAT ": ", p2i(p));
805 } else {
806 st->print(" ");
807 }
808 }
809 st->cr();
810 }
811
812 void os::print_environment_variables(outputStream* st, const char** env_list) {
813 if (env_list) {
814 st->print_cr("Environment Variables:");
815
816 for (int i = 0; env_list[i] != NULL; i++) {
817 char *envvar = ::getenv(env_list[i]);
818 if (envvar != NULL) {
819 st->print("%s", env_list[i]);
820 st->print("=");
821 st->print_cr("%s", envvar);
822 }
823 }
824 }
825 }
826
827 void os::print_cpu_info(outputStream* st, char* buf, size_t buflen) {
828 // cpu
829 st->print("CPU:");
830 st->print("total %d", os::processor_count());
831 // It's not safe to query number of active processors after crash
832 // st->print("(active %d)", os::active_processor_count());
833 st->print(" %s", VM_Version::features_string());
834 st->cr();
835 pd_print_cpu_info(st, buf, buflen);
836 }
837
838 // Print a one line string summarizing the cpu, number of cores, memory, and operating system version
839 void os::print_summary_info(outputStream* st, char* buf, size_t buflen) {
840 st->print("Host: ");
841 #ifndef PRODUCT
842 if (get_host_name(buf, buflen)) {
843 st->print("%s, ", buf);
844 }
845 #endif // PRODUCT
846 get_summary_cpu_info(buf, buflen);
847 st->print("%s, ", buf);
848 size_t mem = physical_memory()/G;
849 if (mem == 0) { // for low memory systems
850 mem = physical_memory()/M;
851 st->print("%d cores, " SIZE_FORMAT "M, ", processor_count(), mem);
852 } else {
853 st->print("%d cores, " SIZE_FORMAT "G, ", processor_count(), mem);
854 }
855 get_summary_os_info(buf, buflen);
856 st->print_raw(buf);
857 st->cr();
858 }
859
860 void os::print_date_and_time(outputStream *st, char* buf, size_t buflen) {
861 const int secs_per_day = 86400;
862 const int secs_per_hour = 3600;
863 const int secs_per_min = 60;
864
865 time_t tloc;
866 (void)time(&tloc);
867 char* timestring = ctime(&tloc); // ctime adds newline.
868 // edit out the newline
869 char* nl = strchr(timestring, '\n');
870 if (nl != NULL) {
871 *nl = '\0';
872 }
873
874 struct tm tz;
875 if (localtime_pd(&tloc, &tz) != NULL) {
876 ::strftime(buf, buflen, "%Z", &tz);
877 st->print("Time: %s %s", timestring, buf);
878 } else {
879 st->print("Time: %s", timestring);
880 }
881
882 double t = os::elapsedTime();
883 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in
884 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int
885 // before printf. We lost some precision, but who cares?
886 int eltime = (int)t; // elapsed time in seconds
887
888 // print elapsed time in a human-readable format:
889 int eldays = eltime / secs_per_day;
890 int day_secs = eldays * secs_per_day;
891 int elhours = (eltime - day_secs) / secs_per_hour;
892 int hour_secs = elhours * secs_per_hour;
893 int elmins = (eltime - day_secs - hour_secs) / secs_per_min;
894 int minute_secs = elmins * secs_per_min;
895 int elsecs = (eltime - day_secs - hour_secs - minute_secs);
896 st->print_cr(" elapsed time: %d seconds (%dd %dh %dm %ds)", eltime, eldays, elhours, elmins, elsecs);
897 }
898
899 // moved from debug.cpp (used to be find()) but still called from there
900 // The verbose parameter is only set by the debug code in one case
901 void os::print_location(outputStream* st, intptr_t x, bool verbose) {
902 address addr = (address)x;
903 CodeBlob* b = CodeCache::find_blob_unsafe(addr);
904 if (b != NULL) {
905 if (b->is_buffer_blob()) {
906 // the interpreter is generated into a buffer blob
907 InterpreterCodelet* i = Interpreter::codelet_containing(addr);
908 if (i != NULL) {
909 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an Interpreter codelet", p2i(addr), (int)(addr - i->code_begin()));
910 i->print_on(st);
911 return;
912 }
913 if (Interpreter::contains(addr)) {
914 st->print_cr(INTPTR_FORMAT " is pointing into interpreter code"
915 " (not bytecode specific)", p2i(addr));
916 return;
917 }
918 //
919 if (AdapterHandlerLibrary::contains(b)) {
920 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an AdapterHandler", p2i(addr), (int)(addr - b->code_begin()));
921 AdapterHandlerLibrary::print_handler_on(st, b);
922 }
923 // the stubroutines are generated into a buffer blob
924 StubCodeDesc* d = StubCodeDesc::desc_for(addr);
925 if (d != NULL) {
926 st->print_cr(INTPTR_FORMAT " is at begin+%d in a stub", p2i(addr), (int)(addr - d->begin()));
927 d->print_on(st);
928 st->cr();
929 return;
930 }
931 if (StubRoutines::contains(addr)) {
932 st->print_cr(INTPTR_FORMAT " is pointing to an (unnamed) stub routine", p2i(addr));
933 return;
934 }
935 // the InlineCacheBuffer is using stubs generated into a buffer blob
936 if (InlineCacheBuffer::contains(addr)) {
937 st->print_cr(INTPTR_FORMAT " is pointing into InlineCacheBuffer", p2i(addr));
938 return;
939 }
940 VtableStub* v = VtableStubs::stub_containing(addr);
941 if (v != NULL) {
942 st->print_cr(INTPTR_FORMAT " is at entry_point+%d in a vtable stub", p2i(addr), (int)(addr - v->entry_point()));
943 v->print_on(st);
944 st->cr();
945 return;
946 }
947 }
948 nmethod* nm = b->as_nmethod_or_null();
949 if (nm != NULL) {
950 ResourceMark rm;
951 st->print(INTPTR_FORMAT " is at entry_point+%d in (nmethod*)" INTPTR_FORMAT,
952 p2i(addr), (int)(addr - nm->entry_point()), p2i(nm));
953 if (verbose) {
954 st->print(" for ");
955 nm->method()->print_value_on(st);
956 }
957 st->cr();
958 nm->print_nmethod(verbose);
959 return;
960 }
961 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in ", p2i(addr), (int)(addr - b->code_begin()));
962 b->print_on(st);
963 return;
964 }
965
966 if (Universe::heap()->is_in(addr)) {
967 HeapWord* p = Universe::heap()->block_start(addr);
968 bool print = false;
969 // If we couldn't find it it just may mean that heap wasn't parsable
970 // See if we were just given an oop directly
971 if (p != NULL && Universe::heap()->block_is_obj(p)) {
972 print = true;
973 } else if (p == NULL && ((oopDesc*)addr)->is_oop()) {
974 p = (HeapWord*) addr;
975 print = true;
976 }
977 if (print) {
978 if (p == (HeapWord*) addr) {
979 st->print_cr(INTPTR_FORMAT " is an oop", p2i(addr));
980 } else {
981 st->print_cr(INTPTR_FORMAT " is pointing into object: " INTPTR_FORMAT, p2i(addr), p2i(p));
982 }
983 oop(p)->print_on(st);
984 return;
985 }
986 } else {
987 if (Universe::heap()->is_in_reserved(addr)) {
988 st->print_cr(INTPTR_FORMAT " is an unallocated location "
989 "in the heap", p2i(addr));
990 return;
991 }
992 }
993 if (JNIHandles::is_global_handle((jobject) addr)) {
994 st->print_cr(INTPTR_FORMAT " is a global jni handle", p2i(addr));
995 return;
996 }
997 if (JNIHandles::is_weak_global_handle((jobject) addr)) {
998 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", p2i(addr));
999 return;
1000 }
1001 #ifndef PRODUCT
1002 // we don't keep the block list in product mode
1003 if (JNIHandleBlock::any_contains((jobject) addr)) {
1004 st->print_cr(INTPTR_FORMAT " is a local jni handle", p2i(addr));
1005 return;
1006 }
1007 #endif
1008
1009 for(JavaThread *thread = Threads::first(); thread; thread = thread->next()) {
1010 // Check for privilege stack
1011 if (thread->privileged_stack_top() != NULL &&
1012 thread->privileged_stack_top()->contains(addr)) {
1013 st->print_cr(INTPTR_FORMAT " is pointing into the privilege stack "
1014 "for thread: " INTPTR_FORMAT, p2i(addr), p2i(thread));
1015 if (verbose) thread->print_on(st);
1016 return;
1017 }
1018 // If the addr is a java thread print information about that.
1019 if (addr == (address)thread) {
1020 if (verbose) {
1021 thread->print_on(st);
1022 } else {
1023 st->print_cr(INTPTR_FORMAT " is a thread", p2i(addr));
1024 }
1025 return;
1026 }
1027 // If the addr is in the stack region for this thread then report that
1028 // and print thread info
1029 if (thread->on_local_stack(addr)) {
1030 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: "
1031 INTPTR_FORMAT, p2i(addr), p2i(thread));
1032 if (verbose) thread->print_on(st);
1033 return;
1034 }
1035
1036 }
1037
1038 // Check if in metaspace and print types that have vptrs (only method now)
1039 if (Metaspace::contains(addr)) {
1040 if (Method::has_method_vptr((const void*)addr)) {
1041 ((Method*)addr)->print_value_on(st);
1042 st->cr();
1043 } else {
1044 // Use addr->print() from the debugger instead (not here)
1045 st->print_cr(INTPTR_FORMAT " is pointing into metadata", p2i(addr));
1046 }
1047 return;
1048 }
1049
1050 // Try an OS specific find
1051 if (os::find(addr, st)) {
1052 return;
1053 }
1054
1055 st->print_cr(INTPTR_FORMAT " is an unknown value", p2i(addr));
1056 }
1057
1058 // Looks like all platforms except IA64 can use the same function to check
1059 // if C stack is walkable beyond current frame. The check for fp() is not
1060 // necessary on Sparc, but it's harmless.
1061 bool os::is_first_C_frame(frame* fr) {
1062 #if (defined(IA64) && !defined(AIX)) && !defined(_WIN32)
1063 // On IA64 we have to check if the callers bsp is still valid
1064 // (i.e. within the register stack bounds).
1065 // Notice: this only works for threads created by the VM and only if
1066 // we walk the current stack!!! If we want to be able to walk
1067 // arbitrary other threads, we'll have to somehow store the thread
1068 // object in the frame.
1069 Thread *thread = Thread::current();
1070 if ((address)fr->fp() <=
1071 thread->register_stack_base() HPUX_ONLY(+ 0x0) LINUX_ONLY(+ 0x50)) {
1072 // This check is a little hacky, because on Linux the first C
1073 // frame's ('start_thread') register stack frame starts at
1074 // "register_stack_base + 0x48" while on HPUX, the first C frame's
1075 // ('__pthread_bound_body') register stack frame seems to really
1076 // start at "register_stack_base".
1077 return true;
1078 } else {
1079 return false;
1080 }
1081 #elif defined(IA64) && defined(_WIN32)
1082 return true;
1083 #else
1084 // Load up sp, fp, sender sp and sender fp, check for reasonable values.
1085 // Check usp first, because if that's bad the other accessors may fault
1086 // on some architectures. Ditto ufp second, etc.
1087 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1);
1088 // sp on amd can be 32 bit aligned.
1089 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1);
1090
1091 uintptr_t usp = (uintptr_t)fr->sp();
1092 if ((usp & sp_align_mask) != 0) return true;
1093
1094 uintptr_t ufp = (uintptr_t)fr->fp();
1095 if ((ufp & fp_align_mask) != 0) return true;
1096
1097 uintptr_t old_sp = (uintptr_t)fr->sender_sp();
1098 if ((old_sp & sp_align_mask) != 0) return true;
1099 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true;
1100
1101 uintptr_t old_fp = (uintptr_t)fr->link();
1102 if ((old_fp & fp_align_mask) != 0) return true;
1103 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true;
1104
1105 // stack grows downwards; if old_fp is below current fp or if the stack
1106 // frame is too large, either the stack is corrupted or fp is not saved
1107 // on stack (i.e. on x86, ebp may be used as general register). The stack
1108 // is not walkable beyond current frame.
1109 if (old_fp < ufp) return true;
1110 if (old_fp - ufp > 64 * K) return true;
1111
1112 return false;
1113 #endif
1114 }
1115
1116 #ifdef ASSERT
1117 extern "C" void test_random() {
1118 const double m = 2147483647;
1119 double mean = 0.0, variance = 0.0, t;
1120 long reps = 10000;
1121 unsigned long seed = 1;
1122
1123 tty->print_cr("seed %ld for %ld repeats...", seed, reps);
1124 os::init_random(seed);
1125 long num;
1126 for (int k = 0; k < reps; k++) {
1127 num = os::random();
1128 double u = (double)num / m;
1129 assert(u >= 0.0 && u <= 1.0, "bad random number!");
1130
1131 // calculate mean and variance of the random sequence
1132 mean += u;
1133 variance += (u*u);
1134 }
1135 mean /= reps;
1136 variance /= (reps - 1);
1137
1138 assert(num == 1043618065, "bad seed");
1139 tty->print_cr("mean of the 1st 10000 numbers: %f", mean);
1140 tty->print_cr("variance of the 1st 10000 numbers: %f", variance);
1141 const double eps = 0.0001;
1142 t = fabsd(mean - 0.5018);
1143 assert(t < eps, "bad mean");
1144 t = (variance - 0.3355) < 0.0 ? -(variance - 0.3355) : variance - 0.3355;
1145 assert(t < eps, "bad variance");
1146 }
1147 #endif
1148
1149
1150 // Set up the boot classpath.
1151
1152 char* os::format_boot_path(const char* format_string,
1153 const char* home,
1154 int home_len,
1155 char fileSep,
1156 char pathSep) {
1157 assert((fileSep == '/' && pathSep == ':') ||
1158 (fileSep == '\\' && pathSep == ';'), "unexpected separator chars");
1159
1160 // Scan the format string to determine the length of the actual
1161 // boot classpath, and handle platform dependencies as well.
1162 int formatted_path_len = 0;
1163 const char* p;
1164 for (p = format_string; *p != 0; ++p) {
1165 if (*p == '%') formatted_path_len += home_len - 1;
1166 ++formatted_path_len;
1167 }
1168
1169 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal);
1170 if (formatted_path == NULL) {
1171 return NULL;
1172 }
1173
1174 // Create boot classpath from format, substituting separator chars and
1175 // java home directory.
1176 char* q = formatted_path;
1177 for (p = format_string; *p != 0; ++p) {
1178 switch (*p) {
1179 case '%':
1180 strcpy(q, home);
1181 q += home_len;
1182 break;
1183 case '/':
1184 *q++ = fileSep;
1185 break;
1186 case ':':
1187 *q++ = pathSep;
1188 break;
1189 default:
1190 *q++ = *p;
1191 }
1192 }
1193 *q = '\0';
1194
1195 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched");
1196 return formatted_path;
1197 }
1198
1199 bool os::set_boot_path(char fileSep, char pathSep) {
1200 const char* home = Arguments::get_java_home();
1201 int home_len = (int)strlen(home);
1202
1203 struct stat st;
1204
1205 // modular image if "modules" jimage exists
1206 char* jimage = format_boot_path("%/lib/" MODULES_IMAGE_NAME, home, home_len, fileSep, pathSep);
1207 if (jimage == NULL) return false;
1208 bool has_jimage = (os::stat(jimage, &st) == 0);
1209 if (has_jimage) {
1210 Arguments::set_sysclasspath(jimage);
1211 FREE_C_HEAP_ARRAY(char, jimage);
1212 return true;
1213 }
1214 FREE_C_HEAP_ARRAY(char, jimage);
1215
1216 // check if developer build with exploded modules
1217 char* base_classes = format_boot_path("%/modules/java.base", home, home_len, fileSep, pathSep);
1218 if (base_classes == NULL) return false;
1219 if (os::stat(base_classes, &st) == 0) {
1220 Arguments::set_sysclasspath(base_classes);
1221 FREE_C_HEAP_ARRAY(char, base_classes);
1222 return true;
1223 }
1224 FREE_C_HEAP_ARRAY(char, base_classes);
1225
1226 return false;
1227 }
1228
1229 /*
1230 * Splits a path, based on its separator, the number of
1231 * elements is returned back in n.
1232 * It is the callers responsibility to:
1233 * a> check the value of n, and n may be 0.
1234 * b> ignore any empty path elements
1235 * c> free up the data.
1236 */
1237 char** os::split_path(const char* path, int* n) {
1238 *n = 0;
1239 if (path == NULL || strlen(path) == 0) {
1240 return NULL;
1241 }
1242 const char psepchar = *os::path_separator();
1243 char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal);
1244 if (inpath == NULL) {
1245 return NULL;
1246 }
1247 strcpy(inpath, path);
1248 int count = 1;
1249 char* p = strchr(inpath, psepchar);
1250 // Get a count of elements to allocate memory
1251 while (p != NULL) {
1252 count++;
1253 p++;
1254 p = strchr(p, psepchar);
1255 }
1256 char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count, mtInternal);
1257 if (opath == NULL) {
1258 return NULL;
1259 }
1260
1261 // do the actual splitting
1262 p = inpath;
1263 for (int i = 0 ; i < count ; i++) {
1264 size_t len = strcspn(p, os::path_separator());
1265 if (len > JVM_MAXPATHLEN) {
1266 return NULL;
1267 }
1268 // allocate the string and add terminator storage
1269 char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
1270 if (s == NULL) {
1271 return NULL;
1272 }
1273 strncpy(s, p, len);
1274 s[len] = '\0';
1275 opath[i] = s;
1276 p += len + 1;
1277 }
1278 FREE_C_HEAP_ARRAY(char, inpath);
1279 *n = count;
1280 return opath;
1281 }
1282
1283 void os::set_memory_serialize_page(address page) {
1284 int count = log2_intptr(sizeof(class JavaThread)) - log2_intptr(64);
1285 _mem_serialize_page = (volatile int32_t *)page;
1286 // We initialize the serialization page shift count here
1287 // We assume a cache line size of 64 bytes
1288 assert(SerializePageShiftCount == count, "JavaThread size changed; "
1289 "SerializePageShiftCount constant should be %d", count);
1290 set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t)));
1291 }
1292
1293 static volatile intptr_t SerializePageLock = 0;
1294
1295 // This method is called from signal handler when SIGSEGV occurs while the current
1296 // thread tries to store to the "read-only" memory serialize page during state
1297 // transition.
1298 void os::block_on_serialize_page_trap() {
1299 log_debug(safepoint)("Block until the serialize page permission restored");
1300
1301 // When VMThread is holding the SerializePageLock during modifying the
1302 // access permission of the memory serialize page, the following call
1303 // will block until the permission of that page is restored to rw.
1304 // Generally, it is unsafe to manipulate locks in signal handlers, but in
1305 // this case, it's OK as the signal is synchronous and we know precisely when
1306 // it can occur.
1307 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page");
1308 Thread::muxRelease(&SerializePageLock);
1309 }
1310
1311 // Serialize all thread state variables
1312 void os::serialize_thread_states() {
1313 // On some platforms such as Solaris & Linux, the time duration of the page
1314 // permission restoration is observed to be much longer than expected due to
1315 // scheduler starvation problem etc. To avoid the long synchronization
1316 // time and expensive page trap spinning, 'SerializePageLock' is used to block
1317 // the mutator thread if such case is encountered. See bug 6546278 for details.
1318 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states");
1319 os::protect_memory((char *)os::get_memory_serialize_page(),
1320 os::vm_page_size(), MEM_PROT_READ);
1321 os::protect_memory((char *)os::get_memory_serialize_page(),
1322 os::vm_page_size(), MEM_PROT_RW);
1323 Thread::muxRelease(&SerializePageLock);
1324 }
1325
1326 // Returns true if the current stack pointer is above the stack shadow
1327 // pages, false otherwise.
1328 bool os::stack_shadow_pages_available(Thread *thread, const methodHandle& method, address sp) {
1329 if (!thread->is_Java_thread()) return false;
1330 // Check if we have StackShadowPages above the yellow zone. This parameter
1331 // is dependent on the depth of the maximum VM call stack possible from
1332 // the handler for stack overflow. 'instanceof' in the stack overflow
1333 // handler or a println uses at least 8k stack of VM and native code
1334 // respectively.
1335 const int framesize_in_bytes =
1336 Interpreter::size_top_interpreter_activation(method()) * wordSize;
1337
1338 address limit = ((JavaThread*)thread)->stack_end() +
1339 (JavaThread::stack_guard_zone_size() + JavaThread::stack_shadow_zone_size());
1340
1341 return sp > (limit + framesize_in_bytes);
1342 }
1343
1344 size_t os::page_size_for_region(size_t region_size, size_t min_pages, bool must_be_aligned) {
1345 assert(min_pages > 0, "sanity");
1346 if (UseLargePages) {
1347 const size_t max_page_size = region_size / min_pages;
1348
1349 for (size_t i = 0; _page_sizes[i] != 0; ++i) {
1350 const size_t page_size = _page_sizes[i];
1351 if (page_size <= max_page_size) {
1352 if (!must_be_aligned || is_size_aligned(region_size, page_size)) {
1353 return page_size;
1354 }
1355 }
1356 }
1357 }
1358
1359 return vm_page_size();
1360 }
1361
1362 size_t os::page_size_for_region_aligned(size_t region_size, size_t min_pages) {
1363 return page_size_for_region(region_size, min_pages, true);
1364 }
1365
1366 size_t os::page_size_for_region_unaligned(size_t region_size, size_t min_pages) {
1367 return page_size_for_region(region_size, min_pages, false);
1368 }
1369
1370 static const char* errno_to_string (int e, bool short_text) {
1371 #define ALL_SHARED_ENUMS(X) \
1372 X(E2BIG, "Argument list too long") \
1373 X(EACCES, "Permission denied") \
1374 X(EADDRINUSE, "Address in use") \
1375 X(EADDRNOTAVAIL, "Address not available") \
1376 X(EAFNOSUPPORT, "Address family not supported") \
1377 X(EAGAIN, "Resource unavailable, try again") \
1378 X(EALREADY, "Connection already in progress") \
1379 X(EBADF, "Bad file descriptor") \
1380 X(EBADMSG, "Bad message") \
1381 X(EBUSY, "Device or resource busy") \
1382 X(ECANCELED, "Operation canceled") \
1383 X(ECHILD, "No child processes") \
1384 X(ECONNABORTED, "Connection aborted") \
1385 X(ECONNREFUSED, "Connection refused") \
1386 X(ECONNRESET, "Connection reset") \
1387 X(EDEADLK, "Resource deadlock would occur") \
1388 X(EDESTADDRREQ, "Destination address required") \
1389 X(EDOM, "Mathematics argument out of domain of function") \
1390 X(EEXIST, "File exists") \
1391 X(EFAULT, "Bad address") \
1392 X(EFBIG, "File too large") \
1393 X(EHOSTUNREACH, "Host is unreachable") \
1394 X(EIDRM, "Identifier removed") \
1395 X(EILSEQ, "Illegal byte sequence") \
1396 X(EINPROGRESS, "Operation in progress") \
1397 X(EINTR, "Interrupted function") \
1398 X(EINVAL, "Invalid argument") \
1399 X(EIO, "I/O error") \
1400 X(EISCONN, "Socket is connected") \
1401 X(EISDIR, "Is a directory") \
1402 X(ELOOP, "Too many levels of symbolic links") \
1403 X(EMFILE, "Too many open files") \
1404 X(EMLINK, "Too many links") \
1405 X(EMSGSIZE, "Message too large") \
1406 X(ENAMETOOLONG, "Filename too long") \
1407 X(ENETDOWN, "Network is down") \
1408 X(ENETRESET, "Connection aborted by network") \
1409 X(ENETUNREACH, "Network unreachable") \
1410 X(ENFILE, "Too many files open in system") \
1411 X(ENOBUFS, "No buffer space available") \
1412 X(ENODATA, "No message is available on the STREAM head read queue") \
1413 X(ENODEV, "No such device") \
1414 X(ENOENT, "No such file or directory") \
1415 X(ENOEXEC, "Executable file format error") \
1416 X(ENOLCK, "No locks available") \
1417 X(ENOLINK, "Reserved") \
1418 X(ENOMEM, "Not enough space") \
1419 X(ENOMSG, "No message of the desired type") \
1420 X(ENOPROTOOPT, "Protocol not available") \
1421 X(ENOSPC, "No space left on device") \
1422 X(ENOSR, "No STREAM resources") \
1423 X(ENOSTR, "Not a STREAM") \
1424 X(ENOSYS, "Function not supported") \
1425 X(ENOTCONN, "The socket is not connected") \
1426 X(ENOTDIR, "Not a directory") \
1427 X(ENOTEMPTY, "Directory not empty") \
1428 X(ENOTSOCK, "Not a socket") \
1429 X(ENOTSUP, "Not supported") \
1430 X(ENOTTY, "Inappropriate I/O control operation") \
1431 X(ENXIO, "No such device or address") \
1432 X(EOPNOTSUPP, "Operation not supported on socket") \
1433 X(EOVERFLOW, "Value too large to be stored in data type") \
1434 X(EPERM, "Operation not permitted") \
1435 X(EPIPE, "Broken pipe") \
1436 X(EPROTO, "Protocol error") \
1437 X(EPROTONOSUPPORT, "Protocol not supported") \
1438 X(EPROTOTYPE, "Protocol wrong type for socket") \
1439 X(ERANGE, "Result too large") \
1440 X(EROFS, "Read-only file system") \
1441 X(ESPIPE, "Invalid seek") \
1442 X(ESRCH, "No such process") \
1443 X(ETIME, "Stream ioctl() timeout") \
1444 X(ETIMEDOUT, "Connection timed out") \
1445 X(ETXTBSY, "Text file busy") \
1446 X(EWOULDBLOCK, "Operation would block") \
1447 X(EXDEV, "Cross-device link")
1448
1449 #define DEFINE_ENTRY(e, text) { e, #e, text },
1450
1451 static const struct {
1452 int v;
1453 const char* short_text;
1454 const char* long_text;
1455 } table [] = {
1456
1457 ALL_SHARED_ENUMS(DEFINE_ENTRY)
1458
1459 // The following enums are not defined on all platforms.
1460 #ifdef ESTALE
1461 DEFINE_ENTRY(ESTALE, "Reserved")
1462 #endif
1463 #ifdef EDQUOT
1464 DEFINE_ENTRY(EDQUOT, "Reserved")
1465 #endif
1466 #ifdef EMULTIHOP
1467 DEFINE_ENTRY(EMULTIHOP, "Reserved")
1468 #endif
1469
1470 // End marker.
1471 { -1, "Unknown errno", "Unknown error" }
1472
1473 };
1474
1475 #undef DEFINE_ENTRY
1476 #undef ALL_FLAGS
1477
1478 int i = 0;
1479 while (table[i].v != -1 && table[i].v != e) {
1480 i ++;
1481 }
1482
1483 return short_text ? table[i].short_text : table[i].long_text;
1484
1485 }
1486
1487 const char* os::strerror(int e) {
1488 return errno_to_string(e, false);
1489 }
1490
1491 const char* os::errno_name(int e) {
1492 return errno_to_string(e, true);
1493 }
1494
1495 void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count) {
1496 LogTarget(Info, pagesize) log;
1497 if (log.is_enabled()) {
1498 LogStreamCHeap out(log);
1499
1500 out.print("%s: ", str);
1501 for (int i = 0; i < count; ++i) {
1502 out.print(" " SIZE_FORMAT, page_sizes[i]);
1503 }
1504 out.cr();
1505 }
1506 }
1507
1508 #define trace_page_size_params(size) byte_size_in_exact_unit(size), exact_unit_for_byte_size(size)
1509
1510 void os::trace_page_sizes(const char* str,
1511 const size_t region_min_size,
1512 const size_t region_max_size,
1513 const size_t page_size,
1514 const char* base,
1515 const size_t size) {
1516
1517 log_info(pagesize)("%s: "
1518 " min=" SIZE_FORMAT "%s"
1519 " max=" SIZE_FORMAT "%s"
1520 " base=" PTR_FORMAT
1521 " page_size=" SIZE_FORMAT "%s"
1522 " size=" SIZE_FORMAT "%s",
1523 str,
1524 trace_page_size_params(region_min_size),
1525 trace_page_size_params(region_max_size),
1526 p2i(base),
1527 trace_page_size_params(page_size),
1528 trace_page_size_params(size));
1529 }
1530
1531 void os::trace_page_sizes_for_requested_size(const char* str,
1532 const size_t requested_size,
1533 const size_t page_size,
1534 const size_t alignment,
1535 const char* base,
1536 const size_t size) {
1537
1538 log_info(pagesize)("%s:"
1539 " req_size=" SIZE_FORMAT "%s"
1540 " base=" PTR_FORMAT
1541 " page_size=" SIZE_FORMAT "%s"
1542 " alignment=" SIZE_FORMAT "%s"
1543 " size=" SIZE_FORMAT "%s",
1544 str,
1545 trace_page_size_params(requested_size),
1546 p2i(base),
1547 trace_page_size_params(page_size),
1548 trace_page_size_params(alignment),
1549 trace_page_size_params(size));
1550 }
1551
1552
1553 // This is the working definition of a server class machine:
1554 // >= 2 physical CPU's and >=2GB of memory, with some fuzz
1555 // because the graphics memory (?) sometimes masks physical memory.
1556 // If you want to change the definition of a server class machine
1557 // on some OS or platform, e.g., >=4GB on Windows platforms,
1558 // then you'll have to parameterize this method based on that state,
1559 // as was done for logical processors here, or replicate and
1560 // specialize this method for each platform. (Or fix os to have
1561 // some inheritance structure and use subclassing. Sigh.)
1562 // If you want some platform to always or never behave as a server
1563 // class machine, change the setting of AlwaysActAsServerClassMachine
1564 // and NeverActAsServerClassMachine in globals*.hpp.
1565 bool os::is_server_class_machine() {
1566 // First check for the early returns
1567 if (NeverActAsServerClassMachine) {
1568 return false;
1569 }
1570 if (AlwaysActAsServerClassMachine) {
1571 return true;
1572 }
1573 // Then actually look at the machine
1574 bool result = false;
1575 const unsigned int server_processors = 2;
1576 const julong server_memory = 2UL * G;
1577 // We seem not to get our full complement of memory.
1578 // We allow some part (1/8?) of the memory to be "missing",
1579 // based on the sizes of DIMMs, and maybe graphics cards.
1580 const julong missing_memory = 256UL * M;
1581
1582 /* Is this a server class machine? */
1583 if ((os::active_processor_count() >= (int)server_processors) &&
1584 (os::physical_memory() >= (server_memory - missing_memory))) {
1585 const unsigned int logical_processors =
1586 VM_Version::logical_processors_per_package();
1587 if (logical_processors > 1) {
1588 const unsigned int physical_packages =
1589 os::active_processor_count() / logical_processors;
1590 if (physical_packages >= server_processors) {
1591 result = true;
1592 }
1593 } else {
1594 result = true;
1595 }
1596 }
1597 return result;
1598 }
1599
1600 void os::SuspendedThreadTask::run() {
1601 assert(Threads_lock->owned_by_self() || (_thread == VMThread::vm_thread()), "must have threads lock to call this");
1602 internal_do_task();
1603 _done = true;
1604 }
1605
1606 bool os::create_stack_guard_pages(char* addr, size_t bytes) {
1607 return os::pd_create_stack_guard_pages(addr, bytes);
1608 }
1609
1610 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint) {
1611 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1612 if (result != NULL) {
1613 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1614 }
1615
1616 return result;
1617 }
1618
1619 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint,
1620 MEMFLAGS flags) {
1621 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1622 if (result != NULL) {
1623 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1624 MemTracker::record_virtual_memory_type((address)result, flags);
1625 }
1626
1627 return result;
1628 }
1629
1630 char* os::attempt_reserve_memory_at(size_t bytes, char* addr) {
1631 char* result = pd_attempt_reserve_memory_at(bytes, addr);
1632 if (result != NULL) {
1633 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1634 }
1635 return result;
1636 }
1637
1638 void os::split_reserved_memory(char *base, size_t size,
1639 size_t split, bool realloc) {
1640 pd_split_reserved_memory(base, size, split, realloc);
1641 }
1642
1643 bool os::commit_memory(char* addr, size_t bytes, bool executable) {
1644 bool res = pd_commit_memory(addr, bytes, executable);
1645 if (res) {
1646 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1647 }
1648 return res;
1649 }
1650
1651 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint,
1652 bool executable) {
1653 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable);
1654 if (res) {
1655 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1656 }
1657 return res;
1658 }
1659
1660 void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable,
1661 const char* mesg) {
1662 pd_commit_memory_or_exit(addr, bytes, executable, mesg);
1663 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1664 }
1665
1666 void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint,
1667 bool executable, const char* mesg) {
1668 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg);
1669 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1670 }
1671
1672 bool os::uncommit_memory(char* addr, size_t bytes) {
1673 bool res;
1674 if (MemTracker::tracking_level() > NMT_minimal) {
1675 Tracker tkr = MemTracker::get_virtual_memory_uncommit_tracker();
1676 res = pd_uncommit_memory(addr, bytes);
1677 if (res) {
1678 tkr.record((address)addr, bytes);
1679 }
1680 } else {
1681 res = pd_uncommit_memory(addr, bytes);
1682 }
1683 return res;
1684 }
1685
1686 bool os::release_memory(char* addr, size_t bytes) {
1687 bool res;
1688 if (MemTracker::tracking_level() > NMT_minimal) {
1689 Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
1690 res = pd_release_memory(addr, bytes);
1691 if (res) {
1692 tkr.record((address)addr, bytes);
1693 }
1694 } else {
1695 res = pd_release_memory(addr, bytes);
1696 }
1697 return res;
1698 }
1699
1700 void os::pretouch_memory(void* start, void* end) {
1701 for (volatile char *p = (char*)start; p < (char*)end; p += os::vm_page_size()) {
1702 *p = 0;
1703 }
1704 }
1705
1706 char* os::map_memory(int fd, const char* file_name, size_t file_offset,
1707 char *addr, size_t bytes, bool read_only,
1708 bool allow_exec) {
1709 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec);
1710 if (result != NULL) {
1711 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC);
1712 }
1713 return result;
1714 }
1715
1716 char* os::remap_memory(int fd, const char* file_name, size_t file_offset,
1717 char *addr, size_t bytes, bool read_only,
1718 bool allow_exec) {
1719 return pd_remap_memory(fd, file_name, file_offset, addr, bytes,
1720 read_only, allow_exec);
1721 }
1722
1723 bool os::unmap_memory(char *addr, size_t bytes) {
1724 bool result;
1725 if (MemTracker::tracking_level() > NMT_minimal) {
1726 Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
1727 result = pd_unmap_memory(addr, bytes);
1728 if (result) {
1729 tkr.record((address)addr, bytes);
1730 }
1731 } else {
1732 result = pd_unmap_memory(addr, bytes);
1733 }
1734 return result;
1735 }
1736
1737 void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) {
1738 pd_free_memory(addr, bytes, alignment_hint);
1739 }
1740
1741 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
1742 pd_realign_memory(addr, bytes, alignment_hint);
1743 }
1744
1745 #ifndef _WINDOWS
1746 /* try to switch state from state "from" to state "to"
1747 * returns the state set after the method is complete
1748 */
1749 os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from,
1750 os::SuspendResume::State to)
1751 {
1752 os::SuspendResume::State result =
1753 (os::SuspendResume::State) Atomic::cmpxchg((jint) to, (jint *) &_state, (jint) from);
1754 if (result == from) {
1755 // success
1756 return to;
1757 }
1758 return result;
1759 }
1760 #endif
1761
1762 /////////////// Unit tests ///////////////
1763
1764 #ifndef PRODUCT
1765
1766 #define assert_eq(a,b) assert(a == b, SIZE_FORMAT " != " SIZE_FORMAT, a, b)
1767
1768 class TestOS : AllStatic {
1769 static size_t small_page_size() {
1770 return os::vm_page_size();
1771 }
1772
1773 static size_t large_page_size() {
1774 const size_t large_page_size_example = 4 * M;
1775 return os::page_size_for_region_aligned(large_page_size_example, 1);
1776 }
1777
1778 static void test_page_size_for_region_aligned() {
1779 if (UseLargePages) {
1780 const size_t small_page = small_page_size();
1781 const size_t large_page = large_page_size();
1782
1783 if (large_page > small_page) {
1784 size_t num_small_pages_in_large = large_page / small_page;
1785 size_t page = os::page_size_for_region_aligned(large_page, num_small_pages_in_large);
1786
1787 assert_eq(page, small_page);
1788 }
1789 }
1790 }
1791
1792 static void test_page_size_for_region_alignment() {
1793 if (UseLargePages) {
1794 const size_t small_page = small_page_size();
1795 const size_t large_page = large_page_size();
1796 if (large_page > small_page) {
1797 const size_t unaligned_region = large_page + 17;
1798 size_t page = os::page_size_for_region_aligned(unaligned_region, 1);
1799 assert_eq(page, small_page);
1800
1801 const size_t num_pages = 5;
1802 const size_t aligned_region = large_page * num_pages;
1803 page = os::page_size_for_region_aligned(aligned_region, num_pages);
1804 assert_eq(page, large_page);
1805 }
1806 }
1807 }
1808
1809 static void test_page_size_for_region_unaligned() {
1810 if (UseLargePages) {
1811 // Given exact page size, should return that page size.
1812 for (size_t i = 0; os::_page_sizes[i] != 0; i++) {
1813 size_t expected = os::_page_sizes[i];
1814 size_t actual = os::page_size_for_region_unaligned(expected, 1);
1815 assert_eq(expected, actual);
1816 }
1817
1818 // Given slightly larger size than a page size, return the page size.
1819 for (size_t i = 0; os::_page_sizes[i] != 0; i++) {
1820 size_t expected = os::_page_sizes[i];
1821 size_t actual = os::page_size_for_region_unaligned(expected + 17, 1);
1822 assert_eq(expected, actual);
1823 }
1824
1825 // Given a slightly smaller size than a page size,
1826 // return the next smaller page size.
1827 if (os::_page_sizes[1] > os::_page_sizes[0]) {
1828 size_t expected = os::_page_sizes[0];
1829 size_t actual = os::page_size_for_region_unaligned(os::_page_sizes[1] - 17, 1);
1830 assert_eq(actual, expected);
1831 }
1832
1833 // Return small page size for values less than a small page.
1834 size_t small_page = small_page_size();
1835 size_t actual = os::page_size_for_region_unaligned(small_page - 17, 1);
1836 assert_eq(small_page, actual);
1837 }
1838 }
1839
1840 public:
1841 static void run_tests() {
1842 test_page_size_for_region_aligned();
1843 test_page_size_for_region_alignment();
1844 test_page_size_for_region_unaligned();
1845 }
1846 };
1847
1848 void TestOS_test() {
1849 TestOS::run_tests();
1850 }
1851
1852 #endif // PRODUCT