1 /*
2 * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "jvm.h"
27 #include "classfile/classLoader.hpp"
28 #include "classfile/javaClasses.hpp"
29 #include "classfile/moduleEntry.hpp"
30 #include "classfile/systemDictionary.hpp"
31 #include "classfile/vmSymbols.hpp"
32 #include "code/codeCache.hpp"
33 #include "code/icBuffer.hpp"
34 #include "code/vtableStubs.hpp"
35 #include "gc/shared/vmGCOperations.hpp"
36 #include "interpreter/interpreter.hpp"
37 #include "logging/log.hpp"
38 #include "logging/logStream.hpp"
39 #include "memory/allocation.inline.hpp"
40 #ifdef ASSERT
41 #include "memory/guardedMemory.hpp"
42 #endif
43 #include "memory/resourceArea.hpp"
44 #include "oops/oop.inline.hpp"
45 #include "prims/jvm_misc.hpp"
46 #include "prims/privilegedStack.hpp"
47 #include "runtime/arguments.hpp"
48 #include "runtime/atomic.hpp"
49 #include "runtime/frame.inline.hpp"
50 #include "runtime/interfaceSupport.hpp"
51 #include "runtime/java.hpp"
52 #include "runtime/javaCalls.hpp"
53 #include "runtime/mutexLocker.hpp"
54 #include "runtime/os.inline.hpp"
55 #include "runtime/stubRoutines.hpp"
56 #include "runtime/thread.inline.hpp"
57 #include "runtime/threadSMR.hpp"
58 #include "runtime/vm_version.hpp"
59 #include "services/attachListener.hpp"
60 #include "services/mallocTracker.hpp"
61 #include "services/memTracker.hpp"
62 #include "services/nmtCommon.hpp"
63 #include "services/threadService.hpp"
64 #include "utilities/align.hpp"
65 #include "utilities/defaultStream.hpp"
66 #include "utilities/events.hpp"
67
68 # include <signal.h>
69 # include <errno.h>
70
71 OSThread* os::_starting_thread = NULL;
72 address os::_polling_page = NULL;
73 volatile int32_t* os::_mem_serialize_page = NULL;
74 uintptr_t os::_serialize_page_mask = 0;
75 volatile unsigned int os::_rand_seed = 1;
76 int os::_processor_count = 0;
77 int os::_initial_active_processor_count = 0;
78 size_t os::_page_sizes[os::page_sizes_max];
79
80 #ifndef PRODUCT
81 julong os::num_mallocs = 0; // # of calls to malloc/realloc
82 julong os::alloc_bytes = 0; // # of bytes allocated
83 julong os::num_frees = 0; // # of calls to free
84 julong os::free_bytes = 0; // # of bytes freed
85 #endif
86
87 static juint cur_malloc_words = 0; // current size for MallocMaxTestWords
88
89 void os_init_globals() {
90 // Called from init_globals().
91 // See Threads::create_vm() in thread.cpp, and init.cpp.
92 os::init_globals();
93 }
94
95 // Fill in buffer with current local time as an ISO-8601 string.
96 // E.g., yyyy-mm-ddThh:mm:ss-zzzz.
97 // Returns buffer, or NULL if it failed.
98 // This would mostly be a call to
99 // strftime(...., "%Y-%m-%d" "T" "%H:%M:%S" "%z", ....)
100 // except that on Windows the %z behaves badly, so we do it ourselves.
101 // Also, people wanted milliseconds on there,
102 // and strftime doesn't do milliseconds.
103 char* os::iso8601_time(char* buffer, size_t buffer_length, bool utc) {
104 // Output will be of the form "YYYY-MM-DDThh:mm:ss.mmm+zzzz\0"
105 // 1 2
106 // 12345678901234567890123456789
107 // format string: "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d"
108 static const size_t needed_buffer = 29;
109
110 // Sanity check the arguments
111 if (buffer == NULL) {
112 assert(false, "NULL buffer");
113 return NULL;
114 }
115 if (buffer_length < needed_buffer) {
116 assert(false, "buffer_length too small");
117 return NULL;
118 }
119 // Get the current time
120 jlong milliseconds_since_19700101 = javaTimeMillis();
121 const int milliseconds_per_microsecond = 1000;
122 const time_t seconds_since_19700101 =
123 milliseconds_since_19700101 / milliseconds_per_microsecond;
124 const int milliseconds_after_second =
125 milliseconds_since_19700101 % milliseconds_per_microsecond;
126 // Convert the time value to a tm and timezone variable
127 struct tm time_struct;
128 if (utc) {
129 if (gmtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
130 assert(false, "Failed gmtime_pd");
131 return NULL;
132 }
133 } else {
134 if (localtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
135 assert(false, "Failed localtime_pd");
136 return NULL;
137 }
138 }
139 #if defined(_ALLBSD_SOURCE)
140 const time_t zone = (time_t) time_struct.tm_gmtoff;
141 #else
142 const time_t zone = timezone;
143 #endif
144
145 // If daylight savings time is in effect,
146 // we are 1 hour East of our time zone
147 const time_t seconds_per_minute = 60;
148 const time_t minutes_per_hour = 60;
149 const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour;
150 time_t UTC_to_local = zone;
151 if (time_struct.tm_isdst > 0) {
152 UTC_to_local = UTC_to_local - seconds_per_hour;
153 }
154
155 // No offset when dealing with UTC
156 if (utc) {
157 UTC_to_local = 0;
158 }
159
160 // Compute the time zone offset.
161 // localtime_pd() sets timezone to the difference (in seconds)
162 // between UTC and and local time.
163 // ISO 8601 says we need the difference between local time and UTC,
164 // we change the sign of the localtime_pd() result.
165 const time_t local_to_UTC = -(UTC_to_local);
166 // Then we have to figure out if if we are ahead (+) or behind (-) UTC.
167 char sign_local_to_UTC = '+';
168 time_t abs_local_to_UTC = local_to_UTC;
169 if (local_to_UTC < 0) {
170 sign_local_to_UTC = '-';
171 abs_local_to_UTC = -(abs_local_to_UTC);
172 }
173 // Convert time zone offset seconds to hours and minutes.
174 const time_t zone_hours = (abs_local_to_UTC / seconds_per_hour);
175 const time_t zone_min =
176 ((abs_local_to_UTC % seconds_per_hour) / seconds_per_minute);
177
178 // Print an ISO 8601 date and time stamp into the buffer
179 const int year = 1900 + time_struct.tm_year;
180 const int month = 1 + time_struct.tm_mon;
181 const int printed = jio_snprintf(buffer, buffer_length,
182 "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d",
183 year,
184 month,
185 time_struct.tm_mday,
186 time_struct.tm_hour,
187 time_struct.tm_min,
188 time_struct.tm_sec,
189 milliseconds_after_second,
190 sign_local_to_UTC,
191 zone_hours,
192 zone_min);
193 if (printed == 0) {
194 assert(false, "Failed jio_printf");
195 return NULL;
196 }
197 return buffer;
198 }
199
200 OSReturn os::set_priority(Thread* thread, ThreadPriority p) {
201 debug_only(Thread::check_for_dangling_thread_pointer(thread);)
202
203 if (p >= MinPriority && p <= MaxPriority) {
204 int priority = java_to_os_priority[p];
205 return set_native_priority(thread, priority);
206 } else {
207 assert(false, "Should not happen");
208 return OS_ERR;
209 }
210 }
211
212 // The mapping from OS priority back to Java priority may be inexact because
213 // Java priorities can map M:1 with native priorities. If you want the definite
214 // Java priority then use JavaThread::java_priority()
215 OSReturn os::get_priority(const Thread* const thread, ThreadPriority& priority) {
216 int p;
217 int os_prio;
218 OSReturn ret = get_native_priority(thread, &os_prio);
219 if (ret != OS_OK) return ret;
220
221 if (java_to_os_priority[MaxPriority] > java_to_os_priority[MinPriority]) {
222 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] > os_prio; p--) ;
223 } else {
224 // niceness values are in reverse order
225 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] < os_prio; p--) ;
226 }
227 priority = (ThreadPriority)p;
228 return OS_OK;
229 }
230
231 bool os::dll_build_name(char* buffer, size_t size, const char* fname) {
232 int n = jio_snprintf(buffer, size, "%s%s%s", JNI_LIB_PREFIX, fname, JNI_LIB_SUFFIX);
233 return (n != -1);
234 }
235
236 // Helper for dll_locate_lib.
237 // Pass buffer and printbuffer as we already printed the path to buffer
238 // when we called get_current_directory. This way we avoid another buffer
239 // of size MAX_PATH.
240 static bool conc_path_file_and_check(char *buffer, char *printbuffer, size_t printbuflen,
241 const char* pname, char lastchar, const char* fname) {
242
243 // Concatenate path and file name, but don't print double path separators.
244 const char *filesep = (WINDOWS_ONLY(lastchar == ':' ||) lastchar == os::file_separator()[0]) ?
245 "" : os::file_separator();
246 int ret = jio_snprintf(printbuffer, printbuflen, "%s%s%s", pname, filesep, fname);
247 // Check whether file exists.
248 if (ret != -1) {
249 struct stat statbuf;
250 return os::stat(buffer, &statbuf) == 0;
251 }
252 return false;
253 }
254
255 bool os::dll_locate_lib(char *buffer, size_t buflen,
256 const char* pname, const char* fname) {
257 bool retval = false;
258
259 size_t fullfnamelen = strlen(JNI_LIB_PREFIX) + strlen(fname) + strlen(JNI_LIB_SUFFIX);
260 char* fullfname = (char*)NEW_C_HEAP_ARRAY(char, fullfnamelen + 1, mtInternal);
261 if (dll_build_name(fullfname, fullfnamelen + 1, fname)) {
262 const size_t pnamelen = pname ? strlen(pname) : 0;
263
264 if (pnamelen == 0) {
265 // If no path given, use current working directory.
266 const char* p = get_current_directory(buffer, buflen);
267 if (p != NULL) {
268 const size_t plen = strlen(buffer);
269 const char lastchar = buffer[plen - 1];
270 retval = conc_path_file_and_check(buffer, &buffer[plen], buflen - plen,
271 "", lastchar, fullfname);
272 }
273 } else if (strchr(pname, *os::path_separator()) != NULL) {
274 // A list of paths. Search for the path that contains the library.
275 int n;
276 char** pelements = split_path(pname, &n);
277 if (pelements != NULL) {
278 for (int i = 0; i < n; i++) {
279 char* path = pelements[i];
280 // Really shouldn't be NULL, but check can't hurt.
281 size_t plen = (path == NULL) ? 0 : strlen(path);
282 if (plen == 0) {
283 continue; // Skip the empty path values.
284 }
285 const char lastchar = path[plen - 1];
286 retval = conc_path_file_and_check(buffer, buffer, buflen, path, lastchar, fullfname);
287 if (retval) break;
288 }
289 // Release the storage allocated by split_path.
290 for (int i = 0; i < n; i++) {
291 if (pelements[i] != NULL) {
292 FREE_C_HEAP_ARRAY(char, pelements[i]);
293 }
294 }
295 FREE_C_HEAP_ARRAY(char*, pelements);
296 }
297 } else {
298 // A definite path.
299 const char lastchar = pname[pnamelen-1];
300 retval = conc_path_file_and_check(buffer, buffer, buflen, pname, lastchar, fullfname);
301 }
302 }
303
304 FREE_C_HEAP_ARRAY(char*, fullfname);
305 return retval;
306 }
307
308 // --------------------- sun.misc.Signal (optional) ---------------------
309
310
311 // SIGBREAK is sent by the keyboard to query the VM state
312 #ifndef SIGBREAK
313 #define SIGBREAK SIGQUIT
314 #endif
315
316 // sigexitnum_pd is a platform-specific special signal used for terminating the Signal thread.
317
318
319 static void signal_thread_entry(JavaThread* thread, TRAPS) {
320 os::set_priority(thread, NearMaxPriority);
321 while (true) {
322 int sig;
323 {
324 // FIXME : Currently we have not decided what should be the status
325 // for this java thread blocked here. Once we decide about
326 // that we should fix this.
327 sig = os::signal_wait();
328 }
329 if (sig == os::sigexitnum_pd()) {
330 // Terminate the signal thread
331 return;
332 }
333
334 switch (sig) {
335 case SIGBREAK: {
336 // Check if the signal is a trigger to start the Attach Listener - in that
337 // case don't print stack traces.
338 if (!DisableAttachMechanism && AttachListener::is_init_trigger()) {
339 continue;
340 }
341 // Print stack traces
342 // Any SIGBREAK operations added here should make sure to flush
343 // the output stream (e.g. tty->flush()) after output. See 4803766.
344 // Each module also prints an extra carriage return after its output.
345 VM_PrintThreads op;
346 VMThread::execute(&op);
347 VM_PrintJNI jni_op;
348 VMThread::execute(&jni_op);
349 VM_FindDeadlocks op1(tty);
350 VMThread::execute(&op1);
351 Universe::print_heap_at_SIGBREAK();
352 if (PrintClassHistogram) {
353 VM_GC_HeapInspection op1(tty, true /* force full GC before heap inspection */);
354 VMThread::execute(&op1);
355 }
356 if (JvmtiExport::should_post_data_dump()) {
357 JvmtiExport::post_data_dump();
358 }
359 break;
360 }
361 default: {
362 // Dispatch the signal to java
363 HandleMark hm(THREAD);
364 Klass* klass = SystemDictionary::resolve_or_null(vmSymbols::jdk_internal_misc_Signal(), THREAD);
365 if (klass != NULL) {
366 JavaValue result(T_VOID);
367 JavaCallArguments args;
368 args.push_int(sig);
369 JavaCalls::call_static(
370 &result,
371 klass,
372 vmSymbols::dispatch_name(),
373 vmSymbols::int_void_signature(),
374 &args,
375 THREAD
376 );
377 }
378 if (HAS_PENDING_EXCEPTION) {
379 // tty is initialized early so we don't expect it to be null, but
380 // if it is we can't risk doing an initialization that might
381 // trigger additional out-of-memory conditions
382 if (tty != NULL) {
383 char klass_name[256];
384 char tmp_sig_name[16];
385 const char* sig_name = "UNKNOWN";
386 InstanceKlass::cast(PENDING_EXCEPTION->klass())->
387 name()->as_klass_external_name(klass_name, 256);
388 if (os::exception_name(sig, tmp_sig_name, 16) != NULL)
389 sig_name = tmp_sig_name;
390 warning("Exception %s occurred dispatching signal %s to handler"
391 "- the VM may need to be forcibly terminated",
392 klass_name, sig_name );
393 }
394 CLEAR_PENDING_EXCEPTION;
395 }
396 }
397 }
398 }
399 }
400
401 void os::init_before_ergo() {
402 initialize_initial_active_processor_count();
403 // We need to initialize large page support here because ergonomics takes some
404 // decisions depending on large page support and the calculated large page size.
405 large_page_init();
406
407 // We need to adapt the configured number of stack protection pages given
408 // in 4K pages to the actual os page size. We must do this before setting
409 // up minimal stack sizes etc. in os::init_2().
410 JavaThread::set_stack_red_zone_size (align_up(StackRedPages * 4 * K, vm_page_size()));
411 JavaThread::set_stack_yellow_zone_size (align_up(StackYellowPages * 4 * K, vm_page_size()));
412 JavaThread::set_stack_reserved_zone_size(align_up(StackReservedPages * 4 * K, vm_page_size()));
413 JavaThread::set_stack_shadow_zone_size (align_up(StackShadowPages * 4 * K, vm_page_size()));
414
415 // VM version initialization identifies some characteristics of the
416 // platform that are used during ergonomic decisions.
417 VM_Version::init_before_ergo();
418 }
419
420 void os::signal_init(TRAPS) {
421 if (!ReduceSignalUsage) {
422 // Setup JavaThread for processing signals
423 Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(), true, CHECK);
424 InstanceKlass* ik = InstanceKlass::cast(k);
425 instanceHandle thread_oop = ik->allocate_instance_handle(CHECK);
426
427 const char thread_name[] = "Signal Dispatcher";
428 Handle string = java_lang_String::create_from_str(thread_name, CHECK);
429
430 // Initialize thread_oop to put it into the system threadGroup
431 Handle thread_group (THREAD, Universe::system_thread_group());
432 JavaValue result(T_VOID);
433 JavaCalls::call_special(&result, thread_oop,
434 ik,
435 vmSymbols::object_initializer_name(),
436 vmSymbols::threadgroup_string_void_signature(),
437 thread_group,
438 string,
439 CHECK);
440
441 Klass* group = SystemDictionary::ThreadGroup_klass();
442 JavaCalls::call_special(&result,
443 thread_group,
444 group,
445 vmSymbols::add_method_name(),
446 vmSymbols::thread_void_signature(),
447 thread_oop, // ARG 1
448 CHECK);
449
450 os::signal_init_pd();
451
452 { MutexLocker mu(Threads_lock);
453 JavaThread* signal_thread = new JavaThread(&signal_thread_entry);
454
455 // At this point it may be possible that no osthread was created for the
456 // JavaThread due to lack of memory. We would have to throw an exception
457 // in that case. However, since this must work and we do not allow
458 // exceptions anyway, check and abort if this fails.
459 if (signal_thread == NULL || signal_thread->osthread() == NULL) {
460 vm_exit_during_initialization("java.lang.OutOfMemoryError",
461 os::native_thread_creation_failed_msg());
462 }
463
464 java_lang_Thread::set_thread(thread_oop(), signal_thread);
465 java_lang_Thread::set_priority(thread_oop(), NearMaxPriority);
466 java_lang_Thread::set_daemon(thread_oop());
467
468 signal_thread->set_threadObj(thread_oop());
469 Threads::add(signal_thread);
470 Thread::start(signal_thread);
471 }
472 // Handle ^BREAK
473 os::signal(SIGBREAK, os::user_handler());
474 }
475 }
476
477
478 void os::terminate_signal_thread() {
479 if (!ReduceSignalUsage)
480 signal_notify(sigexitnum_pd());
481 }
482
483
484 // --------------------- loading libraries ---------------------
485
486 typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *);
487 extern struct JavaVM_ main_vm;
488
489 static void* _native_java_library = NULL;
490
491 void* os::native_java_library() {
492 if (_native_java_library == NULL) {
493 char buffer[JVM_MAXPATHLEN];
494 char ebuf[1024];
495
496 // Try to load verify dll first. In 1.3 java dll depends on it and is not
497 // always able to find it when the loading executable is outside the JDK.
498 // In order to keep working with 1.2 we ignore any loading errors.
499 if (dll_locate_lib(buffer, sizeof(buffer), Arguments::get_dll_dir(),
500 "verify")) {
501 dll_load(buffer, ebuf, sizeof(ebuf));
502 }
503
504 // Load java dll
505 if (dll_locate_lib(buffer, sizeof(buffer), Arguments::get_dll_dir(),
506 "java")) {
507 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf));
508 }
509 if (_native_java_library == NULL) {
510 vm_exit_during_initialization("Unable to load native library", ebuf);
511 }
512
513 #if defined(__OpenBSD__)
514 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so
515 // ignore errors
516 if (dll_locate_lib(buffer, sizeof(buffer), Arguments::get_dll_dir(),
517 "net")) {
518 dll_load(buffer, ebuf, sizeof(ebuf));
519 }
520 #endif
521 }
522 return _native_java_library;
523 }
524
525 /*
526 * Support for finding Agent_On(Un)Load/Attach<_lib_name> if it exists.
527 * If check_lib == true then we are looking for an
528 * Agent_OnLoad_lib_name or Agent_OnAttach_lib_name function to determine if
529 * this library is statically linked into the image.
530 * If check_lib == false then we will look for the appropriate symbol in the
531 * executable if agent_lib->is_static_lib() == true or in the shared library
532 * referenced by 'handle'.
533 */
534 void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib,
535 const char *syms[], size_t syms_len) {
536 assert(agent_lib != NULL, "sanity check");
537 const char *lib_name;
538 void *handle = agent_lib->os_lib();
539 void *entryName = NULL;
540 char *agent_function_name;
541 size_t i;
542
543 // If checking then use the agent name otherwise test is_static_lib() to
544 // see how to process this lookup
545 lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL);
546 for (i = 0; i < syms_len; i++) {
547 agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path());
548 if (agent_function_name == NULL) {
549 break;
550 }
551 entryName = dll_lookup(handle, agent_function_name);
552 FREE_C_HEAP_ARRAY(char, agent_function_name);
553 if (entryName != NULL) {
554 break;
555 }
556 }
557 return entryName;
558 }
559
560 // See if the passed in agent is statically linked into the VM image.
561 bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
562 size_t syms_len) {
563 void *ret;
564 void *proc_handle;
565 void *save_handle;
566
567 assert(agent_lib != NULL, "sanity check");
568 if (agent_lib->name() == NULL) {
569 return false;
570 }
571 proc_handle = get_default_process_handle();
572 // Check for Agent_OnLoad/Attach_lib_name function
573 save_handle = agent_lib->os_lib();
574 // We want to look in this process' symbol table.
575 agent_lib->set_os_lib(proc_handle);
576 ret = find_agent_function(agent_lib, true, syms, syms_len);
577 if (ret != NULL) {
578 // Found an entry point like Agent_OnLoad_lib_name so we have a static agent
579 agent_lib->set_valid();
580 agent_lib->set_static_lib(true);
581 return true;
582 }
583 agent_lib->set_os_lib(save_handle);
584 return false;
585 }
586
587 // --------------------- heap allocation utilities ---------------------
588
589 char *os::strdup(const char *str, MEMFLAGS flags) {
590 size_t size = strlen(str);
591 char *dup_str = (char *)malloc(size + 1, flags);
592 if (dup_str == NULL) return NULL;
593 strcpy(dup_str, str);
594 return dup_str;
595 }
596
597 char* os::strdup_check_oom(const char* str, MEMFLAGS flags) {
598 char* p = os::strdup(str, flags);
599 if (p == NULL) {
600 vm_exit_out_of_memory(strlen(str) + 1, OOM_MALLOC_ERROR, "os::strdup_check_oom");
601 }
602 return p;
603 }
604
605
606 #define paranoid 0 /* only set to 1 if you suspect checking code has bug */
607
608 #ifdef ASSERT
609
610 static void verify_memory(void* ptr) {
611 GuardedMemory guarded(ptr);
612 if (!guarded.verify_guards()) {
613 tty->print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees);
614 tty->print_cr("## memory stomp:");
615 guarded.print_on(tty);
616 fatal("memory stomping error");
617 }
618 }
619
620 #endif
621
622 //
623 // This function supports testing of the malloc out of memory
624 // condition without really running the system out of memory.
625 //
626 static bool has_reached_max_malloc_test_peak(size_t alloc_size) {
627 if (MallocMaxTestWords > 0) {
628 jint words = (jint)(alloc_size / BytesPerWord);
629
630 if ((cur_malloc_words + words) > MallocMaxTestWords) {
631 return true;
632 }
633 Atomic::add(words, (volatile jint *)&cur_malloc_words);
634 }
635 return false;
636 }
637
638 void* os::malloc(size_t size, MEMFLAGS flags) {
639 return os::malloc(size, flags, CALLER_PC);
640 }
641
642 void* os::malloc(size_t size, MEMFLAGS memflags, const NativeCallStack& stack) {
643 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
644 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
645
646 // Since os::malloc can be called when the libjvm.{dll,so} is
647 // first loaded and we don't have a thread yet we must accept NULL also here.
648 assert(!os::ThreadCrashProtection::is_crash_protected(Thread::current_or_null()),
649 "malloc() not allowed when crash protection is set");
650
651 if (size == 0) {
652 // return a valid pointer if size is zero
653 // if NULL is returned the calling functions assume out of memory.
654 size = 1;
655 }
656
657 // NMT support
658 NMT_TrackingLevel level = MemTracker::tracking_level();
659 size_t nmt_header_size = MemTracker::malloc_header_size(level);
660
661 #ifndef ASSERT
662 const size_t alloc_size = size + nmt_header_size;
663 #else
664 const size_t alloc_size = GuardedMemory::get_total_size(size + nmt_header_size);
665 if (size + nmt_header_size > alloc_size) { // Check for rollover.
666 return NULL;
667 }
668 #endif
669
670 // For the test flag -XX:MallocMaxTestWords
671 if (has_reached_max_malloc_test_peak(size)) {
672 return NULL;
673 }
674
675 u_char* ptr;
676 ptr = (u_char*)::malloc(alloc_size);
677
678 #ifdef ASSERT
679 if (ptr == NULL) {
680 return NULL;
681 }
682 // Wrap memory with guard
683 GuardedMemory guarded(ptr, size + nmt_header_size);
684 ptr = guarded.get_user_ptr();
685 #endif
686 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) {
687 tty->print_cr("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr));
688 breakpoint();
689 }
690 debug_only(if (paranoid) verify_memory(ptr));
691 if (PrintMalloc && tty != NULL) {
692 tty->print_cr("os::malloc " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr));
693 }
694
695 // we do not track guard memory
696 return MemTracker::record_malloc((address)ptr, size, memflags, stack, level);
697 }
698
699 void* os::realloc(void *memblock, size_t size, MEMFLAGS flags) {
700 return os::realloc(memblock, size, flags, CALLER_PC);
701 }
702
703 void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, const NativeCallStack& stack) {
704
705 // For the test flag -XX:MallocMaxTestWords
706 if (has_reached_max_malloc_test_peak(size)) {
707 return NULL;
708 }
709
710 if (size == 0) {
711 // return a valid pointer if size is zero
712 // if NULL is returned the calling functions assume out of memory.
713 size = 1;
714 }
715
716 #ifndef ASSERT
717 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
718 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
719 // NMT support
720 void* membase = MemTracker::record_free(memblock);
721 NMT_TrackingLevel level = MemTracker::tracking_level();
722 size_t nmt_header_size = MemTracker::malloc_header_size(level);
723 void* ptr = ::realloc(membase, size + nmt_header_size);
724 return MemTracker::record_malloc(ptr, size, memflags, stack, level);
725 #else
726 if (memblock == NULL) {
727 return os::malloc(size, memflags, stack);
728 }
729 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
730 tty->print_cr("os::realloc caught " PTR_FORMAT, p2i(memblock));
731 breakpoint();
732 }
733 // NMT support
734 void* membase = MemTracker::malloc_base(memblock);
735 verify_memory(membase);
736 // always move the block
737 void* ptr = os::malloc(size, memflags, stack);
738 if (PrintMalloc && tty != NULL) {
739 tty->print_cr("os::realloc " SIZE_FORMAT " bytes, " PTR_FORMAT " --> " PTR_FORMAT, size, p2i(memblock), p2i(ptr));
740 }
741 // Copy to new memory if malloc didn't fail
742 if ( ptr != NULL ) {
743 GuardedMemory guarded(MemTracker::malloc_base(memblock));
744 // Guard's user data contains NMT header
745 size_t memblock_size = guarded.get_user_size() - MemTracker::malloc_header_size(memblock);
746 memcpy(ptr, memblock, MIN2(size, memblock_size));
747 if (paranoid) verify_memory(MemTracker::malloc_base(ptr));
748 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) {
749 tty->print_cr("os::realloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr));
750 breakpoint();
751 }
752 os::free(memblock);
753 }
754 return ptr;
755 #endif
756 }
757
758
759 void os::free(void *memblock) {
760 NOT_PRODUCT(inc_stat_counter(&num_frees, 1));
761 #ifdef ASSERT
762 if (memblock == NULL) return;
763 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
764 if (tty != NULL) tty->print_cr("os::free caught " PTR_FORMAT, p2i(memblock));
765 breakpoint();
766 }
767 void* membase = MemTracker::record_free(memblock);
768 verify_memory(membase);
769
770 GuardedMemory guarded(membase);
771 size_t size = guarded.get_user_size();
772 inc_stat_counter(&free_bytes, size);
773 membase = guarded.release_for_freeing();
774 if (PrintMalloc && tty != NULL) {
775 fprintf(stderr, "os::free " SIZE_FORMAT " bytes --> " PTR_FORMAT "\n", size, (uintptr_t)membase);
776 }
777 ::free(membase);
778 #else
779 void* membase = MemTracker::record_free(memblock);
780 ::free(membase);
781 #endif
782 }
783
784 void os::init_random(unsigned int initval) {
785 _rand_seed = initval;
786 }
787
788
789 static int random_helper(unsigned int rand_seed) {
790 /* standard, well-known linear congruential random generator with
791 * next_rand = (16807*seed) mod (2**31-1)
792 * see
793 * (1) "Random Number Generators: Good Ones Are Hard to Find",
794 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988),
795 * (2) "Two Fast Implementations of the 'Minimal Standard' Random
796 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88.
797 */
798 const unsigned int a = 16807;
799 const unsigned int m = 2147483647;
800 const int q = m / a; assert(q == 127773, "weird math");
801 const int r = m % a; assert(r == 2836, "weird math");
802
803 // compute az=2^31p+q
804 unsigned int lo = a * (rand_seed & 0xFFFF);
805 unsigned int hi = a * (rand_seed >> 16);
806 lo += (hi & 0x7FFF) << 16;
807
808 // if q overflowed, ignore the overflow and increment q
809 if (lo > m) {
810 lo &= m;
811 ++lo;
812 }
813 lo += hi >> 15;
814
815 // if (p+q) overflowed, ignore the overflow and increment (p+q)
816 if (lo > m) {
817 lo &= m;
818 ++lo;
819 }
820 return lo;
821 }
822
823 int os::random() {
824 // Make updating the random seed thread safe.
825 while (true) {
826 unsigned int seed = _rand_seed;
827 unsigned int rand = random_helper(seed);
828 if (Atomic::cmpxchg(rand, &_rand_seed, seed) == seed) {
829 return static_cast<int>(rand);
830 }
831 }
832 }
833
834 // The INITIALIZED state is distinguished from the SUSPENDED state because the
835 // conditions in which a thread is first started are different from those in which
836 // a suspension is resumed. These differences make it hard for us to apply the
837 // tougher checks when starting threads that we want to do when resuming them.
838 // However, when start_thread is called as a result of Thread.start, on a Java
839 // thread, the operation is synchronized on the Java Thread object. So there
840 // cannot be a race to start the thread and hence for the thread to exit while
841 // we are working on it. Non-Java threads that start Java threads either have
842 // to do so in a context in which races are impossible, or should do appropriate
843 // locking.
844
845 void os::start_thread(Thread* thread) {
846 // guard suspend/resume
847 MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag);
848 OSThread* osthread = thread->osthread();
849 osthread->set_state(RUNNABLE);
850 pd_start_thread(thread);
851 }
852
853 void os::abort(bool dump_core) {
854 abort(dump_core && CreateCoredumpOnCrash, NULL, NULL);
855 }
856
857 //---------------------------------------------------------------------------
858 // Helper functions for fatal error handler
859
860 void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) {
861 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking");
862
863 int cols = 0;
864 int cols_per_line = 0;
865 switch (unitsize) {
866 case 1: cols_per_line = 16; break;
867 case 2: cols_per_line = 8; break;
868 case 4: cols_per_line = 4; break;
869 case 8: cols_per_line = 2; break;
870 default: return;
871 }
872
873 address p = start;
874 st->print(PTR_FORMAT ": ", p2i(start));
875 while (p < end) {
876 switch (unitsize) {
877 case 1: st->print("%02x", *(u1*)p); break;
878 case 2: st->print("%04x", *(u2*)p); break;
879 case 4: st->print("%08x", *(u4*)p); break;
880 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break;
881 }
882 p += unitsize;
883 cols++;
884 if (cols >= cols_per_line && p < end) {
885 cols = 0;
886 st->cr();
887 st->print(PTR_FORMAT ": ", p2i(p));
888 } else {
889 st->print(" ");
890 }
891 }
892 st->cr();
893 }
894
895 void os::print_environment_variables(outputStream* st, const char** env_list) {
896 if (env_list) {
897 st->print_cr("Environment Variables:");
898
899 for (int i = 0; env_list[i] != NULL; i++) {
900 char *envvar = ::getenv(env_list[i]);
901 if (envvar != NULL) {
902 st->print("%s", env_list[i]);
903 st->print("=");
904 st->print_cr("%s", envvar);
905 }
906 }
907 }
908 }
909
910 void os::print_cpu_info(outputStream* st, char* buf, size_t buflen) {
911 // cpu
912 st->print("CPU:");
913 st->print("total %d", os::processor_count());
914 // It's not safe to query number of active processors after crash
915 // st->print("(active %d)", os::active_processor_count()); but we can
916 // print the initial number of active processors.
917 // We access the raw value here because the assert in the accessor will
918 // fail if the crash occurs before initialization of this value.
919 st->print(" (initial active %d)", _initial_active_processor_count);
920 st->print(" %s", VM_Version::features_string());
921 st->cr();
922 pd_print_cpu_info(st, buf, buflen);
923 }
924
925 // Print a one line string summarizing the cpu, number of cores, memory, and operating system version
926 void os::print_summary_info(outputStream* st, char* buf, size_t buflen) {
927 st->print("Host: ");
928 #ifndef PRODUCT
929 if (get_host_name(buf, buflen)) {
930 st->print("%s, ", buf);
931 }
932 #endif // PRODUCT
933 get_summary_cpu_info(buf, buflen);
934 st->print("%s, ", buf);
935 size_t mem = physical_memory()/G;
936 if (mem == 0) { // for low memory systems
937 mem = physical_memory()/M;
938 st->print("%d cores, " SIZE_FORMAT "M, ", processor_count(), mem);
939 } else {
940 st->print("%d cores, " SIZE_FORMAT "G, ", processor_count(), mem);
941 }
942 get_summary_os_info(buf, buflen);
943 st->print_raw(buf);
944 st->cr();
945 }
946
947 void os::print_date_and_time(outputStream *st, char* buf, size_t buflen) {
948 const int secs_per_day = 86400;
949 const int secs_per_hour = 3600;
950 const int secs_per_min = 60;
951
952 time_t tloc;
953 (void)time(&tloc);
954 char* timestring = ctime(&tloc); // ctime adds newline.
955 // edit out the newline
956 char* nl = strchr(timestring, '\n');
957 if (nl != NULL) {
958 *nl = '\0';
959 }
960
961 struct tm tz;
962 if (localtime_pd(&tloc, &tz) != NULL) {
963 ::strftime(buf, buflen, "%Z", &tz);
964 st->print("Time: %s %s", timestring, buf);
965 } else {
966 st->print("Time: %s", timestring);
967 }
968
969 double t = os::elapsedTime();
970 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in
971 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int
972 // before printf. We lost some precision, but who cares?
973 int eltime = (int)t; // elapsed time in seconds
974
975 // print elapsed time in a human-readable format:
976 int eldays = eltime / secs_per_day;
977 int day_secs = eldays * secs_per_day;
978 int elhours = (eltime - day_secs) / secs_per_hour;
979 int hour_secs = elhours * secs_per_hour;
980 int elmins = (eltime - day_secs - hour_secs) / secs_per_min;
981 int minute_secs = elmins * secs_per_min;
982 int elsecs = (eltime - day_secs - hour_secs - minute_secs);
983 st->print_cr(" elapsed time: %d seconds (%dd %dh %dm %ds)", eltime, eldays, elhours, elmins, elsecs);
984 }
985
986 // moved from debug.cpp (used to be find()) but still called from there
987 // The verbose parameter is only set by the debug code in one case
988 void os::print_location(outputStream* st, intptr_t x, bool verbose) {
989 address addr = (address)x;
990 CodeBlob* b = CodeCache::find_blob_unsafe(addr);
991 if (b != NULL) {
992 if (b->is_buffer_blob()) {
993 // the interpreter is generated into a buffer blob
994 InterpreterCodelet* i = Interpreter::codelet_containing(addr);
995 if (i != NULL) {
996 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an Interpreter codelet", p2i(addr), (int)(addr - i->code_begin()));
997 i->print_on(st);
998 return;
999 }
1000 if (Interpreter::contains(addr)) {
1001 st->print_cr(INTPTR_FORMAT " is pointing into interpreter code"
1002 " (not bytecode specific)", p2i(addr));
1003 return;
1004 }
1005 //
1006 if (AdapterHandlerLibrary::contains(b)) {
1007 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an AdapterHandler", p2i(addr), (int)(addr - b->code_begin()));
1008 AdapterHandlerLibrary::print_handler_on(st, b);
1009 }
1010 // the stubroutines are generated into a buffer blob
1011 StubCodeDesc* d = StubCodeDesc::desc_for(addr);
1012 if (d != NULL) {
1013 st->print_cr(INTPTR_FORMAT " is at begin+%d in a stub", p2i(addr), (int)(addr - d->begin()));
1014 d->print_on(st);
1015 st->cr();
1016 return;
1017 }
1018 if (StubRoutines::contains(addr)) {
1019 st->print_cr(INTPTR_FORMAT " is pointing to an (unnamed) stub routine", p2i(addr));
1020 return;
1021 }
1022 // the InlineCacheBuffer is using stubs generated into a buffer blob
1023 if (InlineCacheBuffer::contains(addr)) {
1024 st->print_cr(INTPTR_FORMAT " is pointing into InlineCacheBuffer", p2i(addr));
1025 return;
1026 }
1027 VtableStub* v = VtableStubs::stub_containing(addr);
1028 if (v != NULL) {
1029 st->print_cr(INTPTR_FORMAT " is at entry_point+%d in a vtable stub", p2i(addr), (int)(addr - v->entry_point()));
1030 v->print_on(st);
1031 st->cr();
1032 return;
1033 }
1034 }
1035 nmethod* nm = b->as_nmethod_or_null();
1036 if (nm != NULL) {
1037 ResourceMark rm;
1038 st->print(INTPTR_FORMAT " is at entry_point+%d in (nmethod*)" INTPTR_FORMAT,
1039 p2i(addr), (int)(addr - nm->entry_point()), p2i(nm));
1040 if (verbose) {
1041 st->print(" for ");
1042 nm->method()->print_value_on(st);
1043 }
1044 st->cr();
1045 nm->print_nmethod(verbose);
1046 return;
1047 }
1048 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in ", p2i(addr), (int)(addr - b->code_begin()));
1049 b->print_on(st);
1050 return;
1051 }
1052
1053 if (Universe::heap()->is_in(addr)) {
1054 HeapWord* p = Universe::heap()->block_start(addr);
1055 bool print = false;
1056 // If we couldn't find it it just may mean that heap wasn't parsable
1057 // See if we were just given an oop directly
1058 if (p != NULL && Universe::heap()->block_is_obj(p)) {
1059 print = true;
1060 } else if (p == NULL && oopDesc::is_oop(oop(addr))) {
1061 p = (HeapWord*) addr;
1062 print = true;
1063 }
1064 if (print) {
1065 if (p == (HeapWord*) addr) {
1066 st->print_cr(INTPTR_FORMAT " is an oop", p2i(addr));
1067 } else {
1068 st->print_cr(INTPTR_FORMAT " is pointing into object: " INTPTR_FORMAT, p2i(addr), p2i(p));
1069 }
1070 oop(p)->print_on(st);
1071 return;
1072 }
1073 } else {
1074 if (Universe::heap()->is_in_reserved(addr)) {
1075 st->print_cr(INTPTR_FORMAT " is an unallocated location "
1076 "in the heap", p2i(addr));
1077 return;
1078 }
1079 }
1080 if (JNIHandles::is_global_handle((jobject) addr)) {
1081 st->print_cr(INTPTR_FORMAT " is a global jni handle", p2i(addr));
1082 return;
1083 }
1084 if (JNIHandles::is_weak_global_handle((jobject) addr)) {
1085 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", p2i(addr));
1086 return;
1087 }
1088 #ifndef PRODUCT
1089 // we don't keep the block list in product mode
1090 if (JNIHandleBlock::any_contains((jobject) addr)) {
1091 st->print_cr(INTPTR_FORMAT " is a local jni handle", p2i(addr));
1092 return;
1093 }
1094 #endif
1095
1096 for (JavaThreadIteratorWithHandle jtiwh; JavaThread *thread = jtiwh.next(); ) {
1097 // Check for privilege stack
1098 if (thread->privileged_stack_top() != NULL &&
1099 thread->privileged_stack_top()->contains(addr)) {
1100 st->print_cr(INTPTR_FORMAT " is pointing into the privilege stack "
1101 "for thread: " INTPTR_FORMAT, p2i(addr), p2i(thread));
1102 if (verbose) thread->print_on(st);
1103 return;
1104 }
1105 // If the addr is a java thread print information about that.
1106 if (addr == (address)thread) {
1107 if (verbose) {
1108 thread->print_on(st);
1109 } else {
1110 st->print_cr(INTPTR_FORMAT " is a thread", p2i(addr));
1111 }
1112 return;
1113 }
1114 // If the addr is in the stack region for this thread then report that
1115 // and print thread info
1116 if (thread->on_local_stack(addr)) {
1117 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: "
1118 INTPTR_FORMAT, p2i(addr), p2i(thread));
1119 if (verbose) thread->print_on(st);
1120 return;
1121 }
1122 }
1123
1124 // Check if in metaspace and print types that have vptrs (only method now)
1125 if (Metaspace::contains(addr)) {
1126 if (Method::has_method_vptr((const void*)addr)) {
1127 ((Method*)addr)->print_value_on(st);
1128 st->cr();
1129 } else {
1130 // Use addr->print() from the debugger instead (not here)
1131 st->print_cr(INTPTR_FORMAT " is pointing into metadata", p2i(addr));
1132 }
1133 return;
1134 }
1135
1136 // Try an OS specific find
1137 if (os::find(addr, st)) {
1138 return;
1139 }
1140
1141 st->print_cr(INTPTR_FORMAT " is an unknown value", p2i(addr));
1142 }
1143
1144 // Looks like all platforms except IA64 can use the same function to check
1145 // if C stack is walkable beyond current frame. The check for fp() is not
1146 // necessary on Sparc, but it's harmless.
1147 bool os::is_first_C_frame(frame* fr) {
1148 #if (defined(IA64) && !defined(AIX)) && !defined(_WIN32)
1149 // On IA64 we have to check if the callers bsp is still valid
1150 // (i.e. within the register stack bounds).
1151 // Notice: this only works for threads created by the VM and only if
1152 // we walk the current stack!!! If we want to be able to walk
1153 // arbitrary other threads, we'll have to somehow store the thread
1154 // object in the frame.
1155 Thread *thread = Thread::current();
1156 if ((address)fr->fp() <=
1157 thread->register_stack_base() HPUX_ONLY(+ 0x0) LINUX_ONLY(+ 0x50)) {
1158 // This check is a little hacky, because on Linux the first C
1159 // frame's ('start_thread') register stack frame starts at
1160 // "register_stack_base + 0x48" while on HPUX, the first C frame's
1161 // ('__pthread_bound_body') register stack frame seems to really
1162 // start at "register_stack_base".
1163 return true;
1164 } else {
1165 return false;
1166 }
1167 #elif defined(IA64) && defined(_WIN32)
1168 return true;
1169 #else
1170 // Load up sp, fp, sender sp and sender fp, check for reasonable values.
1171 // Check usp first, because if that's bad the other accessors may fault
1172 // on some architectures. Ditto ufp second, etc.
1173 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1);
1174 // sp on amd can be 32 bit aligned.
1175 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1);
1176
1177 uintptr_t usp = (uintptr_t)fr->sp();
1178 if ((usp & sp_align_mask) != 0) return true;
1179
1180 uintptr_t ufp = (uintptr_t)fr->fp();
1181 if ((ufp & fp_align_mask) != 0) return true;
1182
1183 uintptr_t old_sp = (uintptr_t)fr->sender_sp();
1184 if ((old_sp & sp_align_mask) != 0) return true;
1185 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true;
1186
1187 uintptr_t old_fp = (uintptr_t)fr->link();
1188 if ((old_fp & fp_align_mask) != 0) return true;
1189 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true;
1190
1191 // stack grows downwards; if old_fp is below current fp or if the stack
1192 // frame is too large, either the stack is corrupted or fp is not saved
1193 // on stack (i.e. on x86, ebp may be used as general register). The stack
1194 // is not walkable beyond current frame.
1195 if (old_fp < ufp) return true;
1196 if (old_fp - ufp > 64 * K) return true;
1197
1198 return false;
1199 #endif
1200 }
1201
1202
1203 // Set up the boot classpath.
1204
1205 char* os::format_boot_path(const char* format_string,
1206 const char* home,
1207 int home_len,
1208 char fileSep,
1209 char pathSep) {
1210 assert((fileSep == '/' && pathSep == ':') ||
1211 (fileSep == '\\' && pathSep == ';'), "unexpected separator chars");
1212
1213 // Scan the format string to determine the length of the actual
1214 // boot classpath, and handle platform dependencies as well.
1215 int formatted_path_len = 0;
1216 const char* p;
1217 for (p = format_string; *p != 0; ++p) {
1218 if (*p == '%') formatted_path_len += home_len - 1;
1219 ++formatted_path_len;
1220 }
1221
1222 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal);
1223 if (formatted_path == NULL) {
1224 return NULL;
1225 }
1226
1227 // Create boot classpath from format, substituting separator chars and
1228 // java home directory.
1229 char* q = formatted_path;
1230 for (p = format_string; *p != 0; ++p) {
1231 switch (*p) {
1232 case '%':
1233 strcpy(q, home);
1234 q += home_len;
1235 break;
1236 case '/':
1237 *q++ = fileSep;
1238 break;
1239 case ':':
1240 *q++ = pathSep;
1241 break;
1242 default:
1243 *q++ = *p;
1244 }
1245 }
1246 *q = '\0';
1247
1248 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched");
1249 return formatted_path;
1250 }
1251
1252 bool os::set_boot_path(char fileSep, char pathSep) {
1253 const char* home = Arguments::get_java_home();
1254 int home_len = (int)strlen(home);
1255
1256 struct stat st;
1257
1258 // modular image if "modules" jimage exists
1259 char* jimage = format_boot_path("%/lib/" MODULES_IMAGE_NAME, home, home_len, fileSep, pathSep);
1260 if (jimage == NULL) return false;
1261 bool has_jimage = (os::stat(jimage, &st) == 0);
1262 if (has_jimage) {
1263 Arguments::set_sysclasspath(jimage, true);
1264 FREE_C_HEAP_ARRAY(char, jimage);
1265 return true;
1266 }
1267 FREE_C_HEAP_ARRAY(char, jimage);
1268
1269 // check if developer build with exploded modules
1270 char* base_classes = format_boot_path("%/modules/" JAVA_BASE_NAME, home, home_len, fileSep, pathSep);
1271 if (base_classes == NULL) return false;
1272 if (os::stat(base_classes, &st) == 0) {
1273 Arguments::set_sysclasspath(base_classes, false);
1274 FREE_C_HEAP_ARRAY(char, base_classes);
1275 return true;
1276 }
1277 FREE_C_HEAP_ARRAY(char, base_classes);
1278
1279 return false;
1280 }
1281
1282 /*
1283 * Splits a path, based on its separator, the number of
1284 * elements is returned back in n.
1285 * It is the callers responsibility to:
1286 * a> check the value of n, and n may be 0.
1287 * b> ignore any empty path elements
1288 * c> free up the data.
1289 */
1290 char** os::split_path(const char* path, int* n) {
1291 *n = 0;
1292 if (path == NULL || strlen(path) == 0) {
1293 return NULL;
1294 }
1295 const char psepchar = *os::path_separator();
1296 char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal);
1297 if (inpath == NULL) {
1298 return NULL;
1299 }
1300 strcpy(inpath, path);
1301 int count = 1;
1302 char* p = strchr(inpath, psepchar);
1303 // Get a count of elements to allocate memory
1304 while (p != NULL) {
1305 count++;
1306 p++;
1307 p = strchr(p, psepchar);
1308 }
1309 char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count, mtInternal);
1310 if (opath == NULL) {
1311 return NULL;
1312 }
1313
1314 // do the actual splitting
1315 p = inpath;
1316 for (int i = 0 ; i < count ; i++) {
1317 size_t len = strcspn(p, os::path_separator());
1318 if (len > JVM_MAXPATHLEN) {
1319 return NULL;
1320 }
1321 // allocate the string and add terminator storage
1322 char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
1323 if (s == NULL) {
1324 return NULL;
1325 }
1326 strncpy(s, p, len);
1327 s[len] = '\0';
1328 opath[i] = s;
1329 p += len + 1;
1330 }
1331 FREE_C_HEAP_ARRAY(char, inpath);
1332 *n = count;
1333 return opath;
1334 }
1335
1336 void os::set_memory_serialize_page(address page) {
1337 int count = log2_intptr(sizeof(class JavaThread)) - log2_intptr(64);
1338 _mem_serialize_page = (volatile int32_t *)page;
1339 // We initialize the serialization page shift count here
1340 // We assume a cache line size of 64 bytes
1341 assert(SerializePageShiftCount == count, "JavaThread size changed; "
1342 "SerializePageShiftCount constant should be %d", count);
1343 set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t)));
1344 }
1345
1346 static volatile intptr_t SerializePageLock = 0;
1347
1348 // This method is called from signal handler when SIGSEGV occurs while the current
1349 // thread tries to store to the "read-only" memory serialize page during state
1350 // transition.
1351 void os::block_on_serialize_page_trap() {
1352 log_debug(safepoint)("Block until the serialize page permission restored");
1353
1354 // When VMThread is holding the SerializePageLock during modifying the
1355 // access permission of the memory serialize page, the following call
1356 // will block until the permission of that page is restored to rw.
1357 // Generally, it is unsafe to manipulate locks in signal handlers, but in
1358 // this case, it's OK as the signal is synchronous and we know precisely when
1359 // it can occur.
1360 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page");
1361 Thread::muxRelease(&SerializePageLock);
1362 }
1363
1364 // Serialize all thread state variables
1365 void os::serialize_thread_states() {
1366 // On some platforms such as Solaris & Linux, the time duration of the page
1367 // permission restoration is observed to be much longer than expected due to
1368 // scheduler starvation problem etc. To avoid the long synchronization
1369 // time and expensive page trap spinning, 'SerializePageLock' is used to block
1370 // the mutator thread if such case is encountered. See bug 6546278 for details.
1371 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states");
1372 os::protect_memory((char *)os::get_memory_serialize_page(),
1373 os::vm_page_size(), MEM_PROT_READ);
1374 os::protect_memory((char *)os::get_memory_serialize_page(),
1375 os::vm_page_size(), MEM_PROT_RW);
1376 Thread::muxRelease(&SerializePageLock);
1377 }
1378
1379 // Returns true if the current stack pointer is above the stack shadow
1380 // pages, false otherwise.
1381 bool os::stack_shadow_pages_available(Thread *thread, const methodHandle& method, address sp) {
1382 if (!thread->is_Java_thread()) return false;
1383 // Check if we have StackShadowPages above the yellow zone. This parameter
1384 // is dependent on the depth of the maximum VM call stack possible from
1385 // the handler for stack overflow. 'instanceof' in the stack overflow
1386 // handler or a println uses at least 8k stack of VM and native code
1387 // respectively.
1388 const int framesize_in_bytes =
1389 Interpreter::size_top_interpreter_activation(method()) * wordSize;
1390
1391 address limit = ((JavaThread*)thread)->stack_end() +
1392 (JavaThread::stack_guard_zone_size() + JavaThread::stack_shadow_zone_size());
1393
1394 return sp > (limit + framesize_in_bytes);
1395 }
1396
1397 size_t os::page_size_for_region(size_t region_size, size_t min_pages, bool must_be_aligned) {
1398 assert(min_pages > 0, "sanity");
1399 if (UseLargePages) {
1400 const size_t max_page_size = region_size / min_pages;
1401
1402 for (size_t i = 0; _page_sizes[i] != 0; ++i) {
1403 const size_t page_size = _page_sizes[i];
1404 if (page_size <= max_page_size) {
1405 if (!must_be_aligned || is_aligned(region_size, page_size)) {
1406 return page_size;
1407 }
1408 }
1409 }
1410 }
1411
1412 return vm_page_size();
1413 }
1414
1415 size_t os::page_size_for_region_aligned(size_t region_size, size_t min_pages) {
1416 return page_size_for_region(region_size, min_pages, true);
1417 }
1418
1419 size_t os::page_size_for_region_unaligned(size_t region_size, size_t min_pages) {
1420 return page_size_for_region(region_size, min_pages, false);
1421 }
1422
1423 static const char* errno_to_string (int e, bool short_text) {
1424 #define ALL_SHARED_ENUMS(X) \
1425 X(E2BIG, "Argument list too long") \
1426 X(EACCES, "Permission denied") \
1427 X(EADDRINUSE, "Address in use") \
1428 X(EADDRNOTAVAIL, "Address not available") \
1429 X(EAFNOSUPPORT, "Address family not supported") \
1430 X(EAGAIN, "Resource unavailable, try again") \
1431 X(EALREADY, "Connection already in progress") \
1432 X(EBADF, "Bad file descriptor") \
1433 X(EBADMSG, "Bad message") \
1434 X(EBUSY, "Device or resource busy") \
1435 X(ECANCELED, "Operation canceled") \
1436 X(ECHILD, "No child processes") \
1437 X(ECONNABORTED, "Connection aborted") \
1438 X(ECONNREFUSED, "Connection refused") \
1439 X(ECONNRESET, "Connection reset") \
1440 X(EDEADLK, "Resource deadlock would occur") \
1441 X(EDESTADDRREQ, "Destination address required") \
1442 X(EDOM, "Mathematics argument out of domain of function") \
1443 X(EEXIST, "File exists") \
1444 X(EFAULT, "Bad address") \
1445 X(EFBIG, "File too large") \
1446 X(EHOSTUNREACH, "Host is unreachable") \
1447 X(EIDRM, "Identifier removed") \
1448 X(EILSEQ, "Illegal byte sequence") \
1449 X(EINPROGRESS, "Operation in progress") \
1450 X(EINTR, "Interrupted function") \
1451 X(EINVAL, "Invalid argument") \
1452 X(EIO, "I/O error") \
1453 X(EISCONN, "Socket is connected") \
1454 X(EISDIR, "Is a directory") \
1455 X(ELOOP, "Too many levels of symbolic links") \
1456 X(EMFILE, "Too many open files") \
1457 X(EMLINK, "Too many links") \
1458 X(EMSGSIZE, "Message too large") \
1459 X(ENAMETOOLONG, "Filename too long") \
1460 X(ENETDOWN, "Network is down") \
1461 X(ENETRESET, "Connection aborted by network") \
1462 X(ENETUNREACH, "Network unreachable") \
1463 X(ENFILE, "Too many files open in system") \
1464 X(ENOBUFS, "No buffer space available") \
1465 X(ENODATA, "No message is available on the STREAM head read queue") \
1466 X(ENODEV, "No such device") \
1467 X(ENOENT, "No such file or directory") \
1468 X(ENOEXEC, "Executable file format error") \
1469 X(ENOLCK, "No locks available") \
1470 X(ENOLINK, "Reserved") \
1471 X(ENOMEM, "Not enough space") \
1472 X(ENOMSG, "No message of the desired type") \
1473 X(ENOPROTOOPT, "Protocol not available") \
1474 X(ENOSPC, "No space left on device") \
1475 X(ENOSR, "No STREAM resources") \
1476 X(ENOSTR, "Not a STREAM") \
1477 X(ENOSYS, "Function not supported") \
1478 X(ENOTCONN, "The socket is not connected") \
1479 X(ENOTDIR, "Not a directory") \
1480 X(ENOTEMPTY, "Directory not empty") \
1481 X(ENOTSOCK, "Not a socket") \
1482 X(ENOTSUP, "Not supported") \
1483 X(ENOTTY, "Inappropriate I/O control operation") \
1484 X(ENXIO, "No such device or address") \
1485 X(EOPNOTSUPP, "Operation not supported on socket") \
1486 X(EOVERFLOW, "Value too large to be stored in data type") \
1487 X(EPERM, "Operation not permitted") \
1488 X(EPIPE, "Broken pipe") \
1489 X(EPROTO, "Protocol error") \
1490 X(EPROTONOSUPPORT, "Protocol not supported") \
1491 X(EPROTOTYPE, "Protocol wrong type for socket") \
1492 X(ERANGE, "Result too large") \
1493 X(EROFS, "Read-only file system") \
1494 X(ESPIPE, "Invalid seek") \
1495 X(ESRCH, "No such process") \
1496 X(ETIME, "Stream ioctl() timeout") \
1497 X(ETIMEDOUT, "Connection timed out") \
1498 X(ETXTBSY, "Text file busy") \
1499 X(EWOULDBLOCK, "Operation would block") \
1500 X(EXDEV, "Cross-device link")
1501
1502 #define DEFINE_ENTRY(e, text) { e, #e, text },
1503
1504 static const struct {
1505 int v;
1506 const char* short_text;
1507 const char* long_text;
1508 } table [] = {
1509
1510 ALL_SHARED_ENUMS(DEFINE_ENTRY)
1511
1512 // The following enums are not defined on all platforms.
1513 #ifdef ESTALE
1514 DEFINE_ENTRY(ESTALE, "Reserved")
1515 #endif
1516 #ifdef EDQUOT
1517 DEFINE_ENTRY(EDQUOT, "Reserved")
1518 #endif
1519 #ifdef EMULTIHOP
1520 DEFINE_ENTRY(EMULTIHOP, "Reserved")
1521 #endif
1522
1523 // End marker.
1524 { -1, "Unknown errno", "Unknown error" }
1525
1526 };
1527
1528 #undef DEFINE_ENTRY
1529 #undef ALL_FLAGS
1530
1531 int i = 0;
1532 while (table[i].v != -1 && table[i].v != e) {
1533 i ++;
1534 }
1535
1536 return short_text ? table[i].short_text : table[i].long_text;
1537
1538 }
1539
1540 const char* os::strerror(int e) {
1541 return errno_to_string(e, false);
1542 }
1543
1544 const char* os::errno_name(int e) {
1545 return errno_to_string(e, true);
1546 }
1547
1548 void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count) {
1549 LogTarget(Info, pagesize) log;
1550 if (log.is_enabled()) {
1551 LogStream out(log);
1552
1553 out.print("%s: ", str);
1554 for (int i = 0; i < count; ++i) {
1555 out.print(" " SIZE_FORMAT, page_sizes[i]);
1556 }
1557 out.cr();
1558 }
1559 }
1560
1561 #define trace_page_size_params(size) byte_size_in_exact_unit(size), exact_unit_for_byte_size(size)
1562
1563 void os::trace_page_sizes(const char* str,
1564 const size_t region_min_size,
1565 const size_t region_max_size,
1566 const size_t page_size,
1567 const char* base,
1568 const size_t size) {
1569
1570 log_info(pagesize)("%s: "
1571 " min=" SIZE_FORMAT "%s"
1572 " max=" SIZE_FORMAT "%s"
1573 " base=" PTR_FORMAT
1574 " page_size=" SIZE_FORMAT "%s"
1575 " size=" SIZE_FORMAT "%s",
1576 str,
1577 trace_page_size_params(region_min_size),
1578 trace_page_size_params(region_max_size),
1579 p2i(base),
1580 trace_page_size_params(page_size),
1581 trace_page_size_params(size));
1582 }
1583
1584 void os::trace_page_sizes_for_requested_size(const char* str,
1585 const size_t requested_size,
1586 const size_t page_size,
1587 const size_t alignment,
1588 const char* base,
1589 const size_t size) {
1590
1591 log_info(pagesize)("%s:"
1592 " req_size=" SIZE_FORMAT "%s"
1593 " base=" PTR_FORMAT
1594 " page_size=" SIZE_FORMAT "%s"
1595 " alignment=" SIZE_FORMAT "%s"
1596 " size=" SIZE_FORMAT "%s",
1597 str,
1598 trace_page_size_params(requested_size),
1599 p2i(base),
1600 trace_page_size_params(page_size),
1601 trace_page_size_params(alignment),
1602 trace_page_size_params(size));
1603 }
1604
1605
1606 // This is the working definition of a server class machine:
1607 // >= 2 physical CPU's and >=2GB of memory, with some fuzz
1608 // because the graphics memory (?) sometimes masks physical memory.
1609 // If you want to change the definition of a server class machine
1610 // on some OS or platform, e.g., >=4GB on Windows platforms,
1611 // then you'll have to parameterize this method based on that state,
1612 // as was done for logical processors here, or replicate and
1613 // specialize this method for each platform. (Or fix os to have
1614 // some inheritance structure and use subclassing. Sigh.)
1615 // If you want some platform to always or never behave as a server
1616 // class machine, change the setting of AlwaysActAsServerClassMachine
1617 // and NeverActAsServerClassMachine in globals*.hpp.
1618 bool os::is_server_class_machine() {
1619 // First check for the early returns
1620 if (NeverActAsServerClassMachine) {
1621 return false;
1622 }
1623 if (AlwaysActAsServerClassMachine) {
1624 return true;
1625 }
1626 // Then actually look at the machine
1627 bool result = false;
1628 const unsigned int server_processors = 2;
1629 const julong server_memory = 2UL * G;
1630 // We seem not to get our full complement of memory.
1631 // We allow some part (1/8?) of the memory to be "missing",
1632 // based on the sizes of DIMMs, and maybe graphics cards.
1633 const julong missing_memory = 256UL * M;
1634
1635 /* Is this a server class machine? */
1636 if ((os::active_processor_count() >= (int)server_processors) &&
1637 (os::physical_memory() >= (server_memory - missing_memory))) {
1638 const unsigned int logical_processors =
1639 VM_Version::logical_processors_per_package();
1640 if (logical_processors > 1) {
1641 const unsigned int physical_packages =
1642 os::active_processor_count() / logical_processors;
1643 if (physical_packages >= server_processors) {
1644 result = true;
1645 }
1646 } else {
1647 result = true;
1648 }
1649 }
1650 return result;
1651 }
1652
1653 void os::initialize_initial_active_processor_count() {
1654 assert(_initial_active_processor_count == 0, "Initial active processor count already set.");
1655 _initial_active_processor_count = active_processor_count();
1656 log_debug(os)("Initial active processor count set to %d" , _initial_active_processor_count);
1657 }
1658
1659 void os::SuspendedThreadTask::run() {
1660 internal_do_task();
1661 _done = true;
1662 }
1663
1664 bool os::create_stack_guard_pages(char* addr, size_t bytes) {
1665 return os::pd_create_stack_guard_pages(addr, bytes);
1666 }
1667
1668 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint) {
1669 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1670 if (result != NULL) {
1671 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1672 }
1673
1674 return result;
1675 }
1676
1677 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint,
1678 MEMFLAGS flags) {
1679 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1680 if (result != NULL) {
1681 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1682 MemTracker::record_virtual_memory_type((address)result, flags);
1683 }
1684
1685 return result;
1686 }
1687
1688 char* os::attempt_reserve_memory_at(size_t bytes, char* addr) {
1689 char* result = pd_attempt_reserve_memory_at(bytes, addr);
1690 if (result != NULL) {
1691 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1692 }
1693 return result;
1694 }
1695
1696 void os::split_reserved_memory(char *base, size_t size,
1697 size_t split, bool realloc) {
1698 pd_split_reserved_memory(base, size, split, realloc);
1699 }
1700
1701 bool os::commit_memory(char* addr, size_t bytes, bool executable) {
1702 bool res = pd_commit_memory(addr, bytes, executable);
1703 if (res) {
1704 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1705 }
1706 return res;
1707 }
1708
1709 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint,
1710 bool executable) {
1711 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable);
1712 if (res) {
1713 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1714 }
1715 return res;
1716 }
1717
1718 void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable,
1719 const char* mesg) {
1720 pd_commit_memory_or_exit(addr, bytes, executable, mesg);
1721 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1722 }
1723
1724 void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint,
1725 bool executable, const char* mesg) {
1726 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg);
1727 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1728 }
1729
1730 bool os::uncommit_memory(char* addr, size_t bytes) {
1731 bool res;
1732 if (MemTracker::tracking_level() > NMT_minimal) {
1733 Tracker tkr = MemTracker::get_virtual_memory_uncommit_tracker();
1734 res = pd_uncommit_memory(addr, bytes);
1735 if (res) {
1736 tkr.record((address)addr, bytes);
1737 }
1738 } else {
1739 res = pd_uncommit_memory(addr, bytes);
1740 }
1741 return res;
1742 }
1743
1744 bool os::release_memory(char* addr, size_t bytes) {
1745 bool res;
1746 if (MemTracker::tracking_level() > NMT_minimal) {
1747 Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
1748 res = pd_release_memory(addr, bytes);
1749 if (res) {
1750 tkr.record((address)addr, bytes);
1751 }
1752 } else {
1753 res = pd_release_memory(addr, bytes);
1754 }
1755 return res;
1756 }
1757
1758 void os::pretouch_memory(void* start, void* end, size_t page_size) {
1759 for (volatile char *p = (char*)start; p < (char*)end; p += page_size) {
1760 *p = 0;
1761 }
1762 }
1763
1764 char* os::map_memory(int fd, const char* file_name, size_t file_offset,
1765 char *addr, size_t bytes, bool read_only,
1766 bool allow_exec) {
1767 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec);
1768 if (result != NULL) {
1769 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC);
1770 }
1771 return result;
1772 }
1773
1774 char* os::remap_memory(int fd, const char* file_name, size_t file_offset,
1775 char *addr, size_t bytes, bool read_only,
1776 bool allow_exec) {
1777 return pd_remap_memory(fd, file_name, file_offset, addr, bytes,
1778 read_only, allow_exec);
1779 }
1780
1781 bool os::unmap_memory(char *addr, size_t bytes) {
1782 bool result;
1783 if (MemTracker::tracking_level() > NMT_minimal) {
1784 Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
1785 result = pd_unmap_memory(addr, bytes);
1786 if (result) {
1787 tkr.record((address)addr, bytes);
1788 }
1789 } else {
1790 result = pd_unmap_memory(addr, bytes);
1791 }
1792 return result;
1793 }
1794
1795 void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) {
1796 pd_free_memory(addr, bytes, alignment_hint);
1797 }
1798
1799 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
1800 pd_realign_memory(addr, bytes, alignment_hint);
1801 }
1802
1803 #ifndef _WINDOWS
1804 /* try to switch state from state "from" to state "to"
1805 * returns the state set after the method is complete
1806 */
1807 os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from,
1808 os::SuspendResume::State to)
1809 {
1810 os::SuspendResume::State result =
1811 (os::SuspendResume::State) Atomic::cmpxchg((jint) to, (jint *) &_state, (jint) from);
1812 if (result == from) {
1813 // success
1814 return to;
1815 }
1816 return result;
1817 }
1818 #endif