1 /*
2 * Copyright (c) 1997, 2022, 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/javaClasses.hpp"
28 #include "classfile/moduleEntry.hpp"
29 #include "classfile/systemDictionary.hpp"
30 #include "classfile/vmClasses.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/gcVMOperations.hpp"
36 #include "logging/log.hpp"
37 #include "interpreter/interpreter.hpp"
38 #include "logging/log.hpp"
39 #include "logging/logStream.hpp"
40 #include "memory/allocation.inline.hpp"
41 #include "memory/resourceArea.hpp"
42 #include "memory/universe.hpp"
43 #include "oops/compressedKlass.hpp"
44 #include "oops/compressedOops.inline.hpp"
45 #include "oops/oop.inline.hpp"
46 #include "prims/jvm_misc.hpp"
47 #include "runtime/arguments.hpp"
48 #include "runtime/atomic.hpp"
49 #include "runtime/frame.inline.hpp"
50 #include "runtime/handles.inline.hpp"
51 #include "runtime/interfaceSupport.inline.hpp"
52 #include "runtime/java.hpp"
53 #include "runtime/javaCalls.hpp"
54 #include "runtime/jniHandles.hpp"
55 #include "runtime/mutexLocker.hpp"
56 #include "runtime/os.inline.hpp"
57 #include "runtime/osThread.hpp"
58 #include "runtime/safefetch.hpp"
59 #include "runtime/sharedRuntime.hpp"
60 #include "runtime/thread.inline.hpp"
61 #include "runtime/threadSMR.hpp"
62 #include "runtime/vmOperations.hpp"
63 #include "runtime/vm_version.hpp"
64 #include "services/attachListener.hpp"
65 #include "services/mallocTracker.hpp"
66 #include "services/memTracker.hpp"
67 #include "services/nmtPreInit.hpp"
68 #include "services/nmtCommon.hpp"
69 #include "services/threadService.hpp"
70 #include "utilities/align.hpp"
71 #include "utilities/count_trailing_zeros.hpp"
72 #include "utilities/defaultStream.hpp"
73 #include "utilities/events.hpp"
74 #include "utilities/powerOfTwo.hpp"
75
76 #ifndef _WINDOWS
77 # include <poll.h>
78 #endif
79
80 # include <signal.h>
81 # include <errno.h>
82
83 OSThread* os::_starting_thread = NULL;
84 address os::_polling_page = NULL;
85 volatile unsigned int os::_rand_seed = 1234567;
86 int os::_processor_count = 0;
87 int os::_initial_active_processor_count = 0;
88 os::PageSizes os::_page_sizes;
89
90 static size_t cur_malloc_words = 0; // current size for MallocMaxTestWords
91
92 DEBUG_ONLY(bool os::_mutex_init_done = false;)
93
94 int os::snprintf(char* buf, size_t len, const char* fmt, ...) {
95 va_list args;
96 va_start(args, fmt);
97 int result = os::vsnprintf(buf, len, fmt, args);
98 va_end(args);
99 return result;
100 }
101
102 // Fill in buffer with current local time as an ISO-8601 string.
103 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz.
104 // Returns buffer, or NULL if it failed.
105 char* os::iso8601_time(char* buffer, size_t buffer_length, bool utc) {
106 const jlong now = javaTimeMillis();
107 return os::iso8601_time(now, buffer, buffer_length, utc);
108 }
109
110 // Fill in buffer with an ISO-8601 string corresponding to the given javaTimeMillis value
111 // E.g., yyyy-mm-ddThh:mm:ss-zzzz.
112 // Returns buffer, or NULL if it failed.
113 // This would mostly be a call to
114 // strftime(...., "%Y-%m-%d" "T" "%H:%M:%S" "%z", ....)
115 // except that on Windows the %z behaves badly, so we do it ourselves.
116 // Also, people wanted milliseconds on there,
117 // and strftime doesn't do milliseconds.
118 char* os::iso8601_time(jlong milliseconds_since_19700101, char* buffer, size_t buffer_length, bool utc) {
119 // Output will be of the form "YYYY-MM-DDThh:mm:ss.mmm+zzzz\0"
120
121 // Sanity check the arguments
122 if (buffer == NULL) {
123 assert(false, "NULL buffer");
124 return NULL;
125 }
126 if (buffer_length < os::iso8601_timestamp_size) {
127 assert(false, "buffer_length too small");
128 return NULL;
129 }
130 const int milliseconds_per_microsecond = 1000;
131 const time_t seconds_since_19700101 =
132 milliseconds_since_19700101 / milliseconds_per_microsecond;
133 const int milliseconds_after_second =
134 milliseconds_since_19700101 % milliseconds_per_microsecond;
135 // Convert the time value to a tm and timezone variable
136 struct tm time_struct;
137 if (utc) {
138 if (gmtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
139 assert(false, "Failed gmtime_pd");
140 return NULL;
141 }
142 } else {
143 if (localtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
144 assert(false, "Failed localtime_pd");
145 return NULL;
146 }
147 }
148
149 const time_t seconds_per_minute = 60;
150 const time_t minutes_per_hour = 60;
151 const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour;
152
153 // No offset when dealing with UTC
154 time_t UTC_to_local = 0;
155 if (!utc) {
156 #if defined(_ALLBSD_SOURCE) || defined(_GNU_SOURCE)
157 UTC_to_local = -(time_struct.tm_gmtoff);
158 #elif defined(_WINDOWS)
159 long zone;
160 _get_timezone(&zone);
161 UTC_to_local = static_cast<time_t>(zone);
162 #else
163 UTC_to_local = timezone;
164 #endif
165
166 // tm_gmtoff already includes adjustment for daylight saving
167 #if !defined(_ALLBSD_SOURCE) && !defined(_GNU_SOURCE)
168 // If daylight savings time is in effect,
169 // we are 1 hour East of our time zone
170 if (time_struct.tm_isdst > 0) {
171 UTC_to_local = UTC_to_local - seconds_per_hour;
172 }
173 #endif
174 }
175
176 // Compute the time zone offset.
177 // localtime_pd() sets timezone to the difference (in seconds)
178 // between UTC and and local time.
179 // ISO 8601 says we need the difference between local time and UTC,
180 // we change the sign of the localtime_pd() result.
181 const time_t local_to_UTC = -(UTC_to_local);
182 // Then we have to figure out if if we are ahead (+) or behind (-) UTC.
183 char sign_local_to_UTC = '+';
184 time_t abs_local_to_UTC = local_to_UTC;
185 if (local_to_UTC < 0) {
186 sign_local_to_UTC = '-';
187 abs_local_to_UTC = -(abs_local_to_UTC);
188 }
189 // Convert time zone offset seconds to hours and minutes.
190 const time_t zone_hours = (abs_local_to_UTC / seconds_per_hour);
191 const time_t zone_min =
192 ((abs_local_to_UTC % seconds_per_hour) / seconds_per_minute);
193
194 // Print an ISO 8601 date and time stamp into the buffer
195 const int year = 1900 + time_struct.tm_year;
196 const int month = 1 + time_struct.tm_mon;
197 const int printed = jio_snprintf(buffer, buffer_length,
198 "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d",
199 year,
200 month,
201 time_struct.tm_mday,
202 time_struct.tm_hour,
203 time_struct.tm_min,
204 time_struct.tm_sec,
205 milliseconds_after_second,
206 sign_local_to_UTC,
207 zone_hours,
208 zone_min);
209 if (printed == 0) {
210 assert(false, "Failed jio_printf");
211 return NULL;
212 }
213 return buffer;
214 }
215
216 OSReturn os::set_priority(Thread* thread, ThreadPriority p) {
217 debug_only(Thread::check_for_dangling_thread_pointer(thread);)
218
219 if ((p >= MinPriority && p <= MaxPriority) ||
220 (p == CriticalPriority && thread->is_ConcurrentGC_thread())) {
221 int priority = java_to_os_priority[p];
222 return set_native_priority(thread, priority);
223 } else {
224 assert(false, "Should not happen");
225 return OS_ERR;
226 }
227 }
228
229 // The mapping from OS priority back to Java priority may be inexact because
230 // Java priorities can map M:1 with native priorities. If you want the definite
231 // Java priority then use JavaThread::java_priority()
232 OSReturn os::get_priority(const Thread* const thread, ThreadPriority& priority) {
233 int p;
234 int os_prio;
235 OSReturn ret = get_native_priority(thread, &os_prio);
236 if (ret != OS_OK) return ret;
237
238 if (java_to_os_priority[MaxPriority] > java_to_os_priority[MinPriority]) {
239 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] > os_prio; p--) ;
240 } else {
241 // niceness values are in reverse order
242 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] < os_prio; p--) ;
243 }
244 priority = (ThreadPriority)p;
245 return OS_OK;
246 }
247
248 bool os::dll_build_name(char* buffer, size_t size, const char* fname) {
249 int n = jio_snprintf(buffer, size, "%s%s%s", JNI_LIB_PREFIX, fname, JNI_LIB_SUFFIX);
250 return (n != -1);
251 }
252
253 #if !defined(LINUX) && !defined(_WINDOWS)
254 bool os::committed_in_range(address start, size_t size, address& committed_start, size_t& committed_size) {
255 committed_start = start;
256 committed_size = size;
257 return true;
258 }
259 #endif
260
261 // Helper for dll_locate_lib.
262 // Pass buffer and printbuffer as we already printed the path to buffer
263 // when we called get_current_directory. This way we avoid another buffer
264 // of size MAX_PATH.
265 static bool conc_path_file_and_check(char *buffer, char *printbuffer, size_t printbuflen,
266 const char* pname, char lastchar, const char* fname) {
267
268 // Concatenate path and file name, but don't print double path separators.
269 const char *filesep = (WINDOWS_ONLY(lastchar == ':' ||) lastchar == os::file_separator()[0]) ?
270 "" : os::file_separator();
271 int ret = jio_snprintf(printbuffer, printbuflen, "%s%s%s", pname, filesep, fname);
272 // Check whether file exists.
273 if (ret != -1) {
274 struct stat statbuf;
275 return os::stat(buffer, &statbuf) == 0;
276 }
277 return false;
278 }
279
280 // Frees all memory allocated on the heap for the
281 // supplied array of arrays of chars (a), where n
282 // is the number of elements in the array.
283 static void free_array_of_char_arrays(char** a, size_t n) {
284 while (n > 0) {
285 n--;
286 if (a[n] != NULL) {
287 FREE_C_HEAP_ARRAY(char, a[n]);
288 }
289 }
290 FREE_C_HEAP_ARRAY(char*, a);
291 }
292
293 bool os::dll_locate_lib(char *buffer, size_t buflen,
294 const char* pname, const char* fname) {
295 bool retval = false;
296
297 size_t fullfnamelen = strlen(JNI_LIB_PREFIX) + strlen(fname) + strlen(JNI_LIB_SUFFIX);
298 char* fullfname = NEW_C_HEAP_ARRAY(char, fullfnamelen + 1, mtInternal);
299 if (dll_build_name(fullfname, fullfnamelen + 1, fname)) {
300 const size_t pnamelen = pname ? strlen(pname) : 0;
301
302 if (pnamelen == 0) {
303 // If no path given, use current working directory.
304 const char* p = get_current_directory(buffer, buflen);
305 if (p != NULL) {
306 const size_t plen = strlen(buffer);
307 const char lastchar = buffer[plen - 1];
308 retval = conc_path_file_and_check(buffer, &buffer[plen], buflen - plen,
309 "", lastchar, fullfname);
310 }
311 } else if (strchr(pname, *os::path_separator()) != NULL) {
312 // A list of paths. Search for the path that contains the library.
313 size_t n;
314 char** pelements = split_path(pname, &n, fullfnamelen);
315 if (pelements != NULL) {
316 for (size_t i = 0; i < n; i++) {
317 char* path = pelements[i];
318 // Really shouldn't be NULL, but check can't hurt.
319 size_t plen = (path == NULL) ? 0 : strlen(path);
320 if (plen == 0) {
321 continue; // Skip the empty path values.
322 }
323 const char lastchar = path[plen - 1];
324 retval = conc_path_file_and_check(buffer, buffer, buflen, path, lastchar, fullfname);
325 if (retval) break;
326 }
327 // Release the storage allocated by split_path.
328 free_array_of_char_arrays(pelements, n);
329 }
330 } else {
331 // A definite path.
332 const char lastchar = pname[pnamelen-1];
333 retval = conc_path_file_and_check(buffer, buffer, buflen, pname, lastchar, fullfname);
334 }
335 }
336
337 FREE_C_HEAP_ARRAY(char*, fullfname);
338 return retval;
339 }
340
341 // --------------------- sun.misc.Signal (optional) ---------------------
342
343
344 // SIGBREAK is sent by the keyboard to query the VM state
345 #ifndef SIGBREAK
346 #define SIGBREAK SIGQUIT
347 #endif
348
349 // sigexitnum_pd is a platform-specific special signal used for terminating the Signal thread.
350
351
352 static void signal_thread_entry(JavaThread* thread, TRAPS) {
353 os::set_priority(thread, NearMaxPriority);
354 while (true) {
355 int sig;
356 {
357 // FIXME : Currently we have not decided what should be the status
358 // for this java thread blocked here. Once we decide about
359 // that we should fix this.
360 sig = os::signal_wait();
361 }
362 if (sig == os::sigexitnum_pd()) {
363 // Terminate the signal thread
364 return;
365 }
366
367 switch (sig) {
368 case SIGBREAK: {
369 #if INCLUDE_SERVICES
370 // Check if the signal is a trigger to start the Attach Listener - in that
371 // case don't print stack traces.
372 if (!DisableAttachMechanism) {
373 // Attempt to transit state to AL_INITIALIZING.
374 AttachListenerState cur_state = AttachListener::transit_state(AL_INITIALIZING, AL_NOT_INITIALIZED);
375 if (cur_state == AL_INITIALIZING) {
376 // Attach Listener has been started to initialize. Ignore this signal.
377 continue;
378 } else if (cur_state == AL_NOT_INITIALIZED) {
379 // Start to initialize.
380 if (AttachListener::is_init_trigger()) {
381 // Attach Listener has been initialized.
382 // Accept subsequent request.
383 continue;
384 } else {
385 // Attach Listener could not be started.
386 // So we need to transit the state to AL_NOT_INITIALIZED.
387 AttachListener::set_state(AL_NOT_INITIALIZED);
388 }
389 } else if (AttachListener::check_socket_file()) {
390 // Attach Listener has been started, but unix domain socket file
391 // does not exist. So restart Attach Listener.
392 continue;
393 }
394 }
395 #endif
396 // Print stack traces
397 // Any SIGBREAK operations added here should make sure to flush
398 // the output stream (e.g. tty->flush()) after output. See 4803766.
399 // Each module also prints an extra carriage return after its output.
400 VM_PrintThreads op(tty, PrintConcurrentLocks, false /* no extended info */, true /* print JNI handle info */);
401 VMThread::execute(&op);
402 VM_FindDeadlocks op1(tty);
403 VMThread::execute(&op1);
404 Universe::print_heap_at_SIGBREAK();
405 if (PrintClassHistogram) {
406 VM_GC_HeapInspection op1(tty, true /* force full GC before heap inspection */);
407 VMThread::execute(&op1);
408 }
409 if (JvmtiExport::should_post_data_dump()) {
410 JvmtiExport::post_data_dump();
411 }
412 break;
413 }
414 default: {
415 // Dispatch the signal to java
416 HandleMark hm(THREAD);
417 Klass* klass = SystemDictionary::resolve_or_null(vmSymbols::jdk_internal_misc_Signal(), THREAD);
418 if (klass != NULL) {
419 JavaValue result(T_VOID);
420 JavaCallArguments args;
421 args.push_int(sig);
422 JavaCalls::call_static(
423 &result,
424 klass,
425 vmSymbols::dispatch_name(),
426 vmSymbols::int_void_signature(),
427 &args,
428 THREAD
429 );
430 }
431 if (HAS_PENDING_EXCEPTION) {
432 // tty is initialized early so we don't expect it to be null, but
433 // if it is we can't risk doing an initialization that might
434 // trigger additional out-of-memory conditions
435 if (tty != NULL) {
436 char klass_name[256];
437 char tmp_sig_name[16];
438 const char* sig_name = "UNKNOWN";
439 InstanceKlass::cast(PENDING_EXCEPTION->klass())->
440 name()->as_klass_external_name(klass_name, 256);
441 if (os::exception_name(sig, tmp_sig_name, 16) != NULL)
442 sig_name = tmp_sig_name;
443 warning("Exception %s occurred dispatching signal %s to handler"
444 "- the VM may need to be forcibly terminated",
445 klass_name, sig_name );
446 }
447 CLEAR_PENDING_EXCEPTION;
448 }
449 }
450 }
451 }
452 }
453
454 void os::init_before_ergo() {
455 initialize_initial_active_processor_count();
456 // We need to initialize large page support here because ergonomics takes some
457 // decisions depending on large page support and the calculated large page size.
458 large_page_init();
459
460 StackOverflow::initialize_stack_zone_sizes();
461
462 // VM version initialization identifies some characteristics of the
463 // platform that are used during ergonomic decisions.
464 VM_Version::init_before_ergo();
465 }
466
467 void os::initialize_jdk_signal_support(TRAPS) {
468 if (!ReduceSignalUsage) {
469 // Setup JavaThread for processing signals
470 const char* name = "Signal Dispatcher";
471 Handle thread_oop = JavaThread::create_system_thread_object(name, true /* visible */, CHECK);
472
473 JavaThread* thread = new JavaThread(&signal_thread_entry);
474 JavaThread::vm_exit_on_osthread_failure(thread);
475
476 JavaThread::start_internal_daemon(THREAD, thread, thread_oop, NearMaxPriority);
477
478 // Handle ^BREAK
479 os::signal(SIGBREAK, os::user_handler());
480 }
481 }
482
483
484 void os::terminate_signal_thread() {
485 if (!ReduceSignalUsage)
486 signal_notify(sigexitnum_pd());
487 }
488
489
490 // --------------------- loading libraries ---------------------
491
492 typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *);
493 extern struct JavaVM_ main_vm;
494
495 static void* _native_java_library = NULL;
496
497 void* os::native_java_library() {
498 if (_native_java_library == NULL) {
499 char buffer[JVM_MAXPATHLEN];
500 char ebuf[1024];
501
502 // Load java dll
503 if (dll_locate_lib(buffer, sizeof(buffer), Arguments::get_dll_dir(),
504 "java")) {
505 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf));
506 }
507 if (_native_java_library == NULL) {
508 vm_exit_during_initialization("Unable to load native library", ebuf);
509 }
510
511 #if defined(__OpenBSD__)
512 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so
513 // ignore errors
514 if (dll_locate_lib(buffer, sizeof(buffer), Arguments::get_dll_dir(),
515 "net")) {
516 dll_load(buffer, ebuf, sizeof(ebuf));
517 }
518 #endif
519 }
520 return _native_java_library;
521 }
522
523 /*
524 * Support for finding Agent_On(Un)Load/Attach<_lib_name> if it exists.
525 * If check_lib == true then we are looking for an
526 * Agent_OnLoad_lib_name or Agent_OnAttach_lib_name function to determine if
527 * this library is statically linked into the image.
528 * If check_lib == false then we will look for the appropriate symbol in the
529 * executable if agent_lib->is_static_lib() == true or in the shared library
530 * referenced by 'handle'.
531 */
532 void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib,
533 const char *syms[], size_t syms_len) {
534 assert(agent_lib != NULL, "sanity check");
535 const char *lib_name;
536 void *handle = agent_lib->os_lib();
537 void *entryName = NULL;
538 char *agent_function_name;
539 size_t i;
540
541 // If checking then use the agent name otherwise test is_static_lib() to
542 // see how to process this lookup
543 lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL);
544 for (i = 0; i < syms_len; i++) {
545 agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path());
546 if (agent_function_name == NULL) {
547 break;
548 }
549 entryName = dll_lookup(handle, agent_function_name);
550 FREE_C_HEAP_ARRAY(char, agent_function_name);
551 if (entryName != NULL) {
552 break;
553 }
554 }
555 return entryName;
556 }
557
558 // See if the passed in agent is statically linked into the VM image.
559 bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
560 size_t syms_len) {
561 void *ret;
562 void *proc_handle;
563 void *save_handle;
564
565 assert(agent_lib != NULL, "sanity check");
566 if (agent_lib->name() == NULL) {
567 return false;
568 }
569 proc_handle = get_default_process_handle();
570 // Check for Agent_OnLoad/Attach_lib_name function
571 save_handle = agent_lib->os_lib();
572 // We want to look in this process' symbol table.
573 agent_lib->set_os_lib(proc_handle);
574 ret = find_agent_function(agent_lib, true, syms, syms_len);
575 if (ret != NULL) {
576 // Found an entry point like Agent_OnLoad_lib_name so we have a static agent
577 agent_lib->set_valid();
578 agent_lib->set_static_lib(true);
579 return true;
580 }
581 agent_lib->set_os_lib(save_handle);
582 return false;
583 }
584
585 // --------------------- heap allocation utilities ---------------------
586
587 char *os::strdup(const char *str, MEMFLAGS flags) {
588 size_t size = strlen(str);
589 char *dup_str = (char *)malloc(size + 1, flags);
590 if (dup_str == NULL) return NULL;
591 strcpy(dup_str, str);
592 return dup_str;
593 }
594
595 char* os::strdup_check_oom(const char* str, MEMFLAGS flags) {
596 char* p = os::strdup(str, flags);
597 if (p == NULL) {
598 vm_exit_out_of_memory(strlen(str) + 1, OOM_MALLOC_ERROR, "os::strdup_check_oom");
599 }
600 return p;
601 }
602
603 //
604 // This function supports testing of the malloc out of memory
605 // condition without really running the system out of memory.
606 //
607
608 static bool has_reached_max_malloc_test_peak(size_t alloc_size) {
609 if (MallocMaxTestWords > 0) {
610 size_t words = (alloc_size / BytesPerWord);
611
612 if ((cur_malloc_words + words) > MallocMaxTestWords) {
613 return true;
614 }
615 Atomic::add(&cur_malloc_words, words);
616 }
617 return false;
618 }
619
620 #ifdef ASSERT
621 static void check_crash_protection() {
622 assert(!os::ThreadCrashProtection::is_crash_protected(Thread::current_or_null()),
623 "not allowed when crash protection is set");
624 }
625 static void break_if_ptr_caught(void* ptr) {
626 if (p2i(ptr) == (intptr_t)MallocCatchPtr) {
627 log_warning(malloc, free)("ptr caught: " PTR_FORMAT, p2i(ptr));
628 breakpoint();
629 }
630 }
631 #endif // ASSERT
632
633 void* os::malloc(size_t size, MEMFLAGS flags) {
634 return os::malloc(size, flags, CALLER_PC);
635 }
636
637 void* os::malloc(size_t size, MEMFLAGS memflags, const NativeCallStack& stack) {
638
639 // Special handling for NMT preinit phase before arguments are parsed
640 void* rc = NULL;
641 if (NMTPreInit::handle_malloc(&rc, size)) {
642 // No need to fill with 0 because DumpSharedSpaces doesn't use these
643 // early allocations.
644 return rc;
645 }
646
647 DEBUG_ONLY(check_crash_protection());
648
649 // On malloc(0), implementations of malloc(3) have the choice to return either
650 // NULL or a unique non-NULL pointer. To unify libc behavior across our platforms
651 // we chose the latter.
652 size = MAX2((size_t)1, size);
653
654 // For the test flag -XX:MallocMaxTestWords
655 if (has_reached_max_malloc_test_peak(size)) {
656 return NULL;
657 }
658
659 const size_t outer_size = size + MemTracker::overhead_per_malloc();
660
661 void* const outer_ptr = ::malloc(outer_size);
662 if (outer_ptr == NULL) {
663 return NULL;
664 }
665
666 void* const inner_ptr = MemTracker::record_malloc((address)outer_ptr, size, memflags, stack);
667
668 if (DumpSharedSpaces) {
669 // Need to deterministically fill all the alignment gaps in C++ structures.
670 ::memset(inner_ptr, 0, size);
671 } else {
672 DEBUG_ONLY(::memset(inner_ptr, uninitBlockPad, size);)
673 }
674 DEBUG_ONLY(break_if_ptr_caught(inner_ptr);)
675 return inner_ptr;
676 }
677
678 void* os::realloc(void *memblock, size_t size, MEMFLAGS flags) {
679 return os::realloc(memblock, size, flags, CALLER_PC);
680 }
681
682 void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, const NativeCallStack& stack) {
683
684 // Special handling for NMT preinit phase before arguments are parsed
685 void* rc = NULL;
686 if (NMTPreInit::handle_realloc(&rc, memblock, size)) {
687 return rc;
688 }
689
690 if (memblock == NULL) {
691 return os::malloc(size, memflags, stack);
692 }
693
694 DEBUG_ONLY(check_crash_protection());
695
696 // On realloc(p, 0), implementers of realloc(3) have the choice to return either
697 // NULL or a unique non-NULL pointer. To unify libc behavior across our platforms
698 // we chose the latter.
699 size = MAX2((size_t)1, size);
700
701 // For the test flag -XX:MallocMaxTestWords
702 if (has_reached_max_malloc_test_peak(size)) {
703 return NULL;
704 }
705
706 const size_t new_outer_size = size + MemTracker::overhead_per_malloc();
707
708 // If NMT is enabled, this checks for heap overwrites, then de-accounts the old block.
709 void* const old_outer_ptr = MemTracker::record_free(memblock);
710
711 void* const new_outer_ptr = ::realloc(old_outer_ptr, new_outer_size);
712 if (new_outer_ptr == NULL) {
713 return NULL;
714 }
715
716 void* const new_inner_ptr = MemTracker::record_malloc(new_outer_ptr, size, memflags, stack);
717
718 DEBUG_ONLY(break_if_ptr_caught(new_inner_ptr);)
719
720 return new_inner_ptr;
721 }
722
723 void os::free(void *memblock) {
724
725 // Special handling for NMT preinit phase before arguments are parsed
726 if (NMTPreInit::handle_free(memblock)) {
727 return;
728 }
729
730 if (memblock == NULL) {
731 return;
732 }
733
734 DEBUG_ONLY(break_if_ptr_caught(memblock);)
735
736 // If NMT is enabled, this checks for heap overwrites, then de-accounts the old block.
737 void* const old_outer_ptr = MemTracker::record_free(memblock);
738
739 ::free(old_outer_ptr);
740 }
741
742 void os::init_random(unsigned int initval) {
743 _rand_seed = initval;
744 }
745
746
747 int os::next_random(unsigned int rand_seed) {
748 /* standard, well-known linear congruential random generator with
749 * next_rand = (16807*seed) mod (2**31-1)
750 * see
751 * (1) "Random Number Generators: Good Ones Are Hard to Find",
752 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988),
753 * (2) "Two Fast Implementations of the 'Minimal Standard' Random
754 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88.
755 */
756 const unsigned int a = 16807;
757 const unsigned int m = 2147483647;
758 const int q = m / a; assert(q == 127773, "weird math");
759 const int r = m % a; assert(r == 2836, "weird math");
760
761 // compute az=2^31p+q
762 unsigned int lo = a * (rand_seed & 0xFFFF);
763 unsigned int hi = a * (rand_seed >> 16);
764 lo += (hi & 0x7FFF) << 16;
765
766 // if q overflowed, ignore the overflow and increment q
767 if (lo > m) {
768 lo &= m;
769 ++lo;
770 }
771 lo += hi >> 15;
772
773 // if (p+q) overflowed, ignore the overflow and increment (p+q)
774 if (lo > m) {
775 lo &= m;
776 ++lo;
777 }
778 return lo;
779 }
780
781 int os::random() {
782 // Make updating the random seed thread safe.
783 while (true) {
784 unsigned int seed = _rand_seed;
785 unsigned int rand = next_random(seed);
786 if (Atomic::cmpxchg(&_rand_seed, seed, rand, memory_order_relaxed) == seed) {
787 return static_cast<int>(rand);
788 }
789 }
790 }
791
792 // The INITIALIZED state is distinguished from the SUSPENDED state because the
793 // conditions in which a thread is first started are different from those in which
794 // a suspension is resumed. These differences make it hard for us to apply the
795 // tougher checks when starting threads that we want to do when resuming them.
796 // However, when start_thread is called as a result of Thread.start, on a Java
797 // thread, the operation is synchronized on the Java Thread object. So there
798 // cannot be a race to start the thread and hence for the thread to exit while
799 // we are working on it. Non-Java threads that start Java threads either have
800 // to do so in a context in which races are impossible, or should do appropriate
801 // locking.
802
803 void os::start_thread(Thread* thread) {
804 OSThread* osthread = thread->osthread();
805 osthread->set_state(RUNNABLE);
806 pd_start_thread(thread);
807 }
808
809 void os::abort(bool dump_core) {
810 abort(dump_core && CreateCoredumpOnCrash, NULL, NULL);
811 }
812
813 //---------------------------------------------------------------------------
814 // Helper functions for fatal error handler
815
816 bool os::print_function_and_library_name(outputStream* st,
817 address addr,
818 char* buf, int buflen,
819 bool shorten_paths,
820 bool demangle,
821 bool strip_arguments) {
822 // If no scratch buffer given, allocate one here on stack.
823 // (used during error handling; its a coin toss, really, if on-stack allocation
824 // is worse than (raw) C-heap allocation in that case).
825 char* p = buf;
826 if (p == NULL) {
827 p = (char*)::alloca(O_BUFLEN);
828 buflen = O_BUFLEN;
829 }
830 int offset = 0;
831 bool have_function_name = dll_address_to_function_name(addr, p, buflen,
832 &offset, demangle);
833 bool is_function_descriptor = false;
834 #ifdef HAVE_FUNCTION_DESCRIPTORS
835 // When we deal with a function descriptor instead of a real code pointer, try to
836 // resolve it. There is a small chance that a random pointer given to this function
837 // may just happen to look like a valid descriptor, but this is rare and worth the
838 // risk to see resolved function names. But we will print a little suffix to mark
839 // this as a function descriptor for the reader (see below).
840 if (!have_function_name && os::is_readable_pointer(addr)) {
841 address addr2 = (address)os::resolve_function_descriptor(addr);
842 if (have_function_name = is_function_descriptor =
843 dll_address_to_function_name(addr2, p, buflen, &offset, demangle)) {
844 addr = addr2;
845 }
846 }
847 #endif // HAVE_FUNCTION_DESCRIPTORS
848
849 if (have_function_name) {
850 // Print function name, optionally demangled
851 if (demangle && strip_arguments) {
852 char* args_start = strchr(p, '(');
853 if (args_start != NULL) {
854 *args_start = '\0';
855 }
856 }
857 // Print offset. Omit printing if offset is zero, which makes the output
858 // more readable if we print function pointers.
859 if (offset == 0) {
860 st->print("%s", p);
861 } else {
862 st->print("%s+%d", p, offset);
863 }
864 } else {
865 st->print(PTR_FORMAT, p2i(addr));
866 }
867 offset = 0;
868
869 const bool have_library_name = dll_address_to_library_name(addr, p, buflen, &offset);
870 if (have_library_name) {
871 // Cut path parts
872 if (shorten_paths) {
873 char* p2 = strrchr(p, os::file_separator()[0]);
874 if (p2 != NULL) {
875 p = p2 + 1;
876 }
877 }
878 st->print(" in %s", p);
879 if (!have_function_name) { // Omit offset if we already printed the function offset
880 st->print("+%d", offset);
881 }
882 }
883
884 // Write a trailing marker if this was a function descriptor
885 if (have_function_name && is_function_descriptor) {
886 st->print_raw(" (FD)");
887 }
888
889 return have_function_name || have_library_name;
890 }
891
892 void os::print_hex_dump(outputStream* st, address start, address end, int unitsize,
893 int bytes_per_line, address logical_start) {
894 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking");
895
896 start = align_down(start, unitsize);
897 logical_start = align_down(logical_start, unitsize);
898 bytes_per_line = align_up(bytes_per_line, 8);
899
900 int cols = 0;
901 int cols_per_line = bytes_per_line / unitsize;
902
903 address p = start;
904 address logical_p = logical_start;
905
906 // Print out the addresses as if we were starting from logical_start.
907 st->print(PTR_FORMAT ": ", p2i(logical_p));
908 while (p < end) {
909 if (is_readable_pointer(p)) {
910 switch (unitsize) {
911 case 1: st->print("%02x", *(u1*)p); break;
912 case 2: st->print("%04x", *(u2*)p); break;
913 case 4: st->print("%08x", *(u4*)p); break;
914 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break;
915 }
916 } else {
917 st->print("%*.*s", 2*unitsize, 2*unitsize, "????????????????");
918 }
919 p += unitsize;
920 logical_p += unitsize;
921 cols++;
922 if (cols >= cols_per_line && p < end) {
923 cols = 0;
924 st->cr();
925 st->print(PTR_FORMAT ": ", p2i(logical_p));
926 } else {
927 st->print(" ");
928 }
929 }
930 st->cr();
931 }
932
933 void os::print_dhm(outputStream* st, const char* startStr, long sec) {
934 long days = sec/86400;
935 long hours = (sec/3600) - (days * 24);
936 long minutes = (sec/60) - (days * 1440) - (hours * 60);
937 if (startStr == NULL) startStr = "";
938 st->print_cr("%s %ld days %ld:%02ld hours", startStr, days, hours, minutes);
939 }
940
941 void os::print_instructions(outputStream* st, address pc, int unitsize) {
942 st->print_cr("Instructions: (pc=" PTR_FORMAT ")", p2i(pc));
943 print_hex_dump(st, pc - 256, pc + 256, unitsize);
944 }
945
946 void os::print_environment_variables(outputStream* st, const char** env_list) {
947 if (env_list) {
948 st->print_cr("Environment Variables:");
949
950 for (int i = 0; env_list[i] != NULL; i++) {
951 char *envvar = ::getenv(env_list[i]);
952 if (envvar != NULL) {
953 st->print("%s", env_list[i]);
954 st->print("=");
955 st->print("%s", envvar);
956 // Use separate cr() printing to avoid unnecessary buffer operations that might cause truncation.
957 st->cr();
958 }
959 }
960 }
961 }
962
963 void os::print_cpu_info(outputStream* st, char* buf, size_t buflen) {
964 // cpu
965 st->print("CPU:");
966 #if defined(__APPLE__) && !defined(ZERO)
967 if (VM_Version::is_cpu_emulated()) {
968 st->print(" (EMULATED)");
969 }
970 #endif
971 st->print(" total %d", os::processor_count());
972 // It's not safe to query number of active processors after crash
973 // st->print("(active %d)", os::active_processor_count()); but we can
974 // print the initial number of active processors.
975 // We access the raw value here because the assert in the accessor will
976 // fail if the crash occurs before initialization of this value.
977 st->print(" (initial active %d)", _initial_active_processor_count);
978 st->print(" %s", VM_Version::features_string());
979 st->cr();
980 pd_print_cpu_info(st, buf, buflen);
981 }
982
983 // Print a one line string summarizing the cpu, number of cores, memory, and operating system version
984 void os::print_summary_info(outputStream* st, char* buf, size_t buflen) {
985 st->print("Host: ");
986 #ifndef PRODUCT
987 if (get_host_name(buf, buflen)) {
988 st->print("%s, ", buf);
989 }
990 #endif // PRODUCT
991 get_summary_cpu_info(buf, buflen);
992 st->print("%s, ", buf);
993 size_t mem = physical_memory()/G;
994 if (mem == 0) { // for low memory systems
995 mem = physical_memory()/M;
996 st->print("%d cores, " SIZE_FORMAT "M, ", processor_count(), mem);
997 } else {
998 st->print("%d cores, " SIZE_FORMAT "G, ", processor_count(), mem);
999 }
1000 get_summary_os_info(buf, buflen);
1001 st->print_raw(buf);
1002 st->cr();
1003 }
1004
1005 void os::print_date_and_time(outputStream *st, char* buf, size_t buflen) {
1006 const int secs_per_day = 86400;
1007 const int secs_per_hour = 3600;
1008 const int secs_per_min = 60;
1009
1010 time_t tloc;
1011 (void)time(&tloc);
1012 char* timestring = ctime(&tloc); // ctime adds newline.
1013 // edit out the newline
1014 char* nl = strchr(timestring, '\n');
1015 if (nl != NULL) {
1016 *nl = '\0';
1017 }
1018
1019 struct tm tz;
1020 if (localtime_pd(&tloc, &tz) != NULL) {
1021 wchar_t w_buf[80];
1022 size_t n = ::wcsftime(w_buf, 80, L"%Z", &tz);
1023 if (n > 0) {
1024 ::wcstombs(buf, w_buf, buflen);
1025 st->print("Time: %s %s", timestring, buf);
1026 } else {
1027 st->print("Time: %s", timestring);
1028 }
1029 } else {
1030 st->print("Time: %s", timestring);
1031 }
1032
1033 double t = os::elapsedTime();
1034 // NOTE: a crash using printf("%f",...) on Linux was historically noted here.
1035 int eltime = (int)t; // elapsed time in seconds
1036 int eltimeFraction = (int) ((t - eltime) * 1000000);
1037
1038 // print elapsed time in a human-readable format:
1039 int eldays = eltime / secs_per_day;
1040 int day_secs = eldays * secs_per_day;
1041 int elhours = (eltime - day_secs) / secs_per_hour;
1042 int hour_secs = elhours * secs_per_hour;
1043 int elmins = (eltime - day_secs - hour_secs) / secs_per_min;
1044 int minute_secs = elmins * secs_per_min;
1045 int elsecs = (eltime - day_secs - hour_secs - minute_secs);
1046 st->print_cr(" elapsed time: %d.%06d seconds (%dd %dh %dm %ds)", eltime, eltimeFraction, eldays, elhours, elmins, elsecs);
1047 }
1048
1049
1050 // Check if pointer can be read from (4-byte read access).
1051 // Helps to prove validity of a not-NULL pointer.
1052 // Returns true in very early stages of VM life when stub is not yet generated.
1053 bool os::is_readable_pointer(const void* p) {
1054 int* const aligned = (int*) align_down((intptr_t)p, 4);
1055 int cafebabe = 0xcafebabe; // tester value 1
1056 int deadbeef = 0xdeadbeef; // tester value 2
1057 return (SafeFetch32(aligned, cafebabe) != cafebabe) || (SafeFetch32(aligned, deadbeef) != deadbeef);
1058 }
1059
1060 bool os::is_readable_range(const void* from, const void* to) {
1061 if ((uintptr_t)from >= (uintptr_t)to) return false;
1062 for (uintptr_t p = align_down((uintptr_t)from, min_page_size()); p < (uintptr_t)to; p += min_page_size()) {
1063 if (!is_readable_pointer((const void*)p)) {
1064 return false;
1065 }
1066 }
1067 return true;
1068 }
1069
1070
1071 // moved from debug.cpp (used to be find()) but still called from there
1072 // The verbose parameter is only set by the debug code in one case
1073 void os::print_location(outputStream* st, intptr_t x, bool verbose) {
1074 address addr = (address)x;
1075 // Handle NULL first, so later checks don't need to protect against it.
1076 if (addr == NULL) {
1077 st->print_cr("0x0 is NULL");
1078 return;
1079 }
1080
1081 // Check if addr points into a code blob.
1082 CodeBlob* b = CodeCache::find_blob_unsafe(addr);
1083 if (b != NULL) {
1084 b->dump_for_addr(addr, st, verbose);
1085 return;
1086 }
1087
1088 // Check if addr points into Java heap.
1089 if (Universe::heap()->print_location(st, addr)) {
1090 return;
1091 }
1092
1093 bool accessible = is_readable_pointer(addr);
1094
1095 // Check if addr is a JNI handle.
1096 if (align_down((intptr_t)addr, sizeof(intptr_t)) != 0 && accessible) {
1097 if (JNIHandles::is_global_handle((jobject) addr)) {
1098 st->print_cr(INTPTR_FORMAT " is a global jni handle", p2i(addr));
1099 return;
1100 }
1101 if (JNIHandles::is_weak_global_handle((jobject) addr)) {
1102 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", p2i(addr));
1103 return;
1104 }
1105 }
1106
1107 // Check if addr belongs to a Java thread.
1108 for (JavaThreadIteratorWithHandle jtiwh; JavaThread *thread = jtiwh.next(); ) {
1109 // If the addr is a java thread print information about that.
1110 if (addr == (address)thread) {
1111 if (verbose) {
1112 thread->print_on(st);
1113 } else {
1114 st->print_cr(INTPTR_FORMAT " is a thread", p2i(addr));
1115 }
1116 return;
1117 }
1118 // If the addr is in the stack region for this thread then report that
1119 // and print thread info
1120 if (thread->is_in_full_stack(addr)) {
1121 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: "
1122 INTPTR_FORMAT, p2i(addr), p2i(thread));
1123 if (verbose) thread->print_on(st);
1124 return;
1125 }
1126 }
1127
1128 // Check if in metaspace and print types that have vptrs
1129 if (Metaspace::contains(addr)) {
1130 if (Klass::is_valid((Klass*)addr)) {
1131 st->print_cr(INTPTR_FORMAT " is a pointer to class: ", p2i(addr));
1132 ((Klass*)addr)->print_on(st);
1133 } else if (Method::is_valid_method((const Method*)addr)) {
1134 ((Method*)addr)->print_value_on(st);
1135 st->cr();
1136 } else {
1137 // Use addr->print() from the debugger instead (not here)
1138 st->print_cr(INTPTR_FORMAT " is pointing into metadata", p2i(addr));
1139 }
1140 return;
1141 }
1142
1143 // Compressed klass needs to be decoded first.
1144 #ifdef _LP64
1145 if (UseCompressedClassPointers && ((uintptr_t)addr &~ (uintptr_t)max_juint) == 0) {
1146 narrowKlass narrow_klass = (narrowKlass)(uintptr_t)addr;
1147 Klass* k = CompressedKlassPointers::decode_raw(narrow_klass);
1148
1149 if (Klass::is_valid(k)) {
1150 st->print_cr(UINT32_FORMAT " is a compressed pointer to class: " INTPTR_FORMAT, narrow_klass, p2i((HeapWord*)k));
1151 k->print_on(st);
1152 return;
1153 }
1154 }
1155 #endif
1156
1157 // Try an OS specific find
1158 if (os::find(addr, st)) {
1159 return;
1160 }
1161
1162 if (accessible) {
1163 st->print(INTPTR_FORMAT " points into unknown readable memory:", p2i(addr));
1164 if (is_aligned(addr, sizeof(intptr_t))) {
1165 st->print(" " PTR_FORMAT " |", *(intptr_t*)addr);
1166 }
1167 for (address p = addr; p < align_up(addr + 1, sizeof(intptr_t)); ++p) {
1168 st->print(" %02x", *(u1*)p);
1169 }
1170 st->cr();
1171 return;
1172 }
1173
1174 st->print_cr(INTPTR_FORMAT " is an unknown value", p2i(addr));
1175 }
1176
1177 bool is_pointer_bad(intptr_t* ptr) {
1178 return !is_aligned(ptr, sizeof(uintptr_t)) || !os::is_readable_pointer(ptr);
1179 }
1180
1181 // Looks like all platforms can use the same function to check if C
1182 // stack is walkable beyond current frame.
1183 // Returns true if this is not the case, i.e. the frame is possibly
1184 // the first C frame on the stack.
1185 bool os::is_first_C_frame(frame* fr) {
1186
1187 #ifdef _WINDOWS
1188 return true; // native stack isn't walkable on windows this way.
1189 #endif
1190 // Load up sp, fp, sender sp and sender fp, check for reasonable values.
1191 // Check usp first, because if that's bad the other accessors may fault
1192 // on some architectures. Ditto ufp second, etc.
1193
1194 if (is_pointer_bad(fr->sp())) return true;
1195
1196 uintptr_t ufp = (uintptr_t)fr->fp();
1197 if (is_pointer_bad(fr->fp())) return true;
1198
1199 uintptr_t old_sp = (uintptr_t)fr->sender_sp();
1200 if ((uintptr_t)fr->sender_sp() == (uintptr_t)-1 || is_pointer_bad(fr->sender_sp())) return true;
1201
1202 uintptr_t old_fp = (uintptr_t)fr->link_or_null();
1203 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp ||
1204 is_pointer_bad(fr->link_or_null())) return true;
1205
1206 // stack grows downwards; if old_fp is below current fp or if the stack
1207 // frame is too large, either the stack is corrupted or fp is not saved
1208 // on stack (i.e. on x86, ebp may be used as general register). The stack
1209 // is not walkable beyond current frame.
1210 if (old_fp < ufp) return true;
1211 if (old_fp - ufp > 64 * K) return true;
1212
1213 return false;
1214 }
1215
1216 // Set up the boot classpath.
1217
1218 char* os::format_boot_path(const char* format_string,
1219 const char* home,
1220 int home_len,
1221 char fileSep,
1222 char pathSep) {
1223 assert((fileSep == '/' && pathSep == ':') ||
1224 (fileSep == '\\' && pathSep == ';'), "unexpected separator chars");
1225
1226 // Scan the format string to determine the length of the actual
1227 // boot classpath, and handle platform dependencies as well.
1228 int formatted_path_len = 0;
1229 const char* p;
1230 for (p = format_string; *p != 0; ++p) {
1231 if (*p == '%') formatted_path_len += home_len - 1;
1232 ++formatted_path_len;
1233 }
1234
1235 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal);
1236
1237 // Create boot classpath from format, substituting separator chars and
1238 // java home directory.
1239 char* q = formatted_path;
1240 for (p = format_string; *p != 0; ++p) {
1241 switch (*p) {
1242 case '%':
1243 strcpy(q, home);
1244 q += home_len;
1245 break;
1246 case '/':
1247 *q++ = fileSep;
1248 break;
1249 case ':':
1250 *q++ = pathSep;
1251 break;
1252 default:
1253 *q++ = *p;
1254 }
1255 }
1256 *q = '\0';
1257
1258 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched");
1259 return formatted_path;
1260 }
1261
1262 // This function is a proxy to fopen, it tries to add a non standard flag ('e' or 'N')
1263 // that ensures automatic closing of the file on exec. If it can not find support in
1264 // the underlying c library, it will make an extra system call (fcntl) to ensure automatic
1265 // closing of the file on exec.
1266 FILE* os::fopen(const char* path, const char* mode) {
1267 char modified_mode[20];
1268 assert(strlen(mode) + 1 < sizeof(modified_mode), "mode chars plus one extra must fit in buffer");
1269 sprintf(modified_mode, "%s" LINUX_ONLY("e") BSD_ONLY("e") WINDOWS_ONLY("N"), mode);
1270 FILE* file = ::fopen(path, modified_mode);
1271
1272 #if !(defined LINUX || defined BSD || defined _WINDOWS)
1273 // assume fcntl FD_CLOEXEC support as a backup solution when 'e' or 'N'
1274 // is not supported as mode in fopen
1275 if (file != NULL) {
1276 int fd = fileno(file);
1277 if (fd != -1) {
1278 int fd_flags = fcntl(fd, F_GETFD);
1279 if (fd_flags != -1) {
1280 fcntl(fd, F_SETFD, fd_flags | FD_CLOEXEC);
1281 }
1282 }
1283 }
1284 #endif
1285
1286 return file;
1287 }
1288
1289 bool os::set_boot_path(char fileSep, char pathSep) {
1290 const char* home = Arguments::get_java_home();
1291 int home_len = (int)strlen(home);
1292
1293 struct stat st;
1294
1295 // modular image if "modules" jimage exists
1296 char* jimage = format_boot_path("%/lib/" MODULES_IMAGE_NAME, home, home_len, fileSep, pathSep);
1297 if (jimage == NULL) return false;
1298 bool has_jimage = (os::stat(jimage, &st) == 0);
1299 if (has_jimage) {
1300 Arguments::set_sysclasspath(jimage, true);
1301 FREE_C_HEAP_ARRAY(char, jimage);
1302 return true;
1303 }
1304 FREE_C_HEAP_ARRAY(char, jimage);
1305
1306 // check if developer build with exploded modules
1307 char* base_classes = format_boot_path("%/modules/" JAVA_BASE_NAME, home, home_len, fileSep, pathSep);
1308 if (base_classes == NULL) return false;
1309 if (os::stat(base_classes, &st) == 0) {
1310 Arguments::set_sysclasspath(base_classes, false);
1311 FREE_C_HEAP_ARRAY(char, base_classes);
1312 return true;
1313 }
1314 FREE_C_HEAP_ARRAY(char, base_classes);
1315
1316 return false;
1317 }
1318
1319 bool os::file_exists(const char* filename) {
1320 struct stat statbuf;
1321 if (filename == NULL || strlen(filename) == 0) {
1322 return false;
1323 }
1324 return os::stat(filename, &statbuf) == 0;
1325 }
1326
1327 // Splits a path, based on its separator, the number of
1328 // elements is returned back in "elements".
1329 // file_name_length is used as a modifier for each path's
1330 // length when compared to JVM_MAXPATHLEN. So if you know
1331 // each returned path will have something appended when
1332 // in use, you can pass the length of that in
1333 // file_name_length, to ensure we detect if any path
1334 // exceeds the maximum path length once prepended onto
1335 // the sub-path/file name.
1336 // It is the callers responsibility to:
1337 // a> check the value of "elements", which may be 0.
1338 // b> ignore any empty path elements
1339 // c> free up the data.
1340 char** os::split_path(const char* path, size_t* elements, size_t file_name_length) {
1341 *elements = (size_t)0;
1342 if (path == NULL || strlen(path) == 0 || file_name_length == (size_t)NULL) {
1343 return NULL;
1344 }
1345 const char psepchar = *os::path_separator();
1346 char* inpath = NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal);
1347 strcpy(inpath, path);
1348 size_t count = 1;
1349 char* p = strchr(inpath, psepchar);
1350 // Get a count of elements to allocate memory
1351 while (p != NULL) {
1352 count++;
1353 p++;
1354 p = strchr(p, psepchar);
1355 }
1356
1357 char** opath = NEW_C_HEAP_ARRAY(char*, count, mtInternal);
1358
1359 // do the actual splitting
1360 p = inpath;
1361 for (size_t i = 0 ; i < count ; i++) {
1362 size_t len = strcspn(p, os::path_separator());
1363 if (len + file_name_length > JVM_MAXPATHLEN) {
1364 // release allocated storage before exiting the vm
1365 free_array_of_char_arrays(opath, i++);
1366 vm_exit_during_initialization("The VM tried to use a path that exceeds the maximum path length for "
1367 "this system. Review path-containing parameters and properties, such as "
1368 "sun.boot.library.path, to identify potential sources for this path.");
1369 }
1370 // allocate the string and add terminator storage
1371 char* s = NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
1372 strncpy(s, p, len);
1373 s[len] = '\0';
1374 opath[i] = s;
1375 p += len + 1;
1376 }
1377 FREE_C_HEAP_ARRAY(char, inpath);
1378 *elements = count;
1379 return opath;
1380 }
1381
1382 // Returns true if the current stack pointer is above the stack shadow
1383 // pages, false otherwise.
1384 bool os::stack_shadow_pages_available(Thread *thread, const methodHandle& method, address sp) {
1385 if (!thread->is_Java_thread()) return false;
1386 // Check if we have StackShadowPages above the guard zone. This parameter
1387 // is dependent on the depth of the maximum VM call stack possible from
1388 // the handler for stack overflow. 'instanceof' in the stack overflow
1389 // handler or a println uses at least 8k stack of VM and native code
1390 // respectively.
1391 const int framesize_in_bytes =
1392 Interpreter::size_top_interpreter_activation(method()) * wordSize;
1393
1394 address limit = JavaThread::cast(thread)->stack_overflow_state()->shadow_zone_safe_limit();
1395 return sp > (limit + framesize_in_bytes);
1396 }
1397
1398 size_t os::page_size_for_region(size_t region_size, size_t min_pages, bool must_be_aligned) {
1399 assert(min_pages > 0, "sanity");
1400 if (UseLargePages) {
1401 const size_t max_page_size = region_size / min_pages;
1402
1403 for (size_t page_size = page_sizes().largest(); page_size != 0;
1404 page_size = page_sizes().next_smaller(page_size)) {
1405 if (page_size <= max_page_size) {
1406 if (!must_be_aligned || is_aligned(region_size, page_size)) {
1407 return page_size;
1408 }
1409 }
1410 }
1411 }
1412
1413 return vm_page_size();
1414 }
1415
1416 size_t os::page_size_for_region_aligned(size_t region_size, size_t min_pages) {
1417 return page_size_for_region(region_size, min_pages, true);
1418 }
1419
1420 size_t os::page_size_for_region_unaligned(size_t region_size, size_t min_pages) {
1421 return page_size_for_region(region_size, min_pages, false);
1422 }
1423
1424 #ifndef MAX_PATH
1425 #define MAX_PATH (2 * K)
1426 #endif
1427
1428 void os::pause() {
1429 char filename[MAX_PATH];
1430 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
1431 jio_snprintf(filename, MAX_PATH, "%s", PauseAtStartupFile);
1432 } else {
1433 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
1434 }
1435
1436 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
1437 if (fd != -1) {
1438 struct stat buf;
1439 ::close(fd);
1440 while (::stat(filename, &buf) == 0) {
1441 #if defined(_WINDOWS)
1442 Sleep(100);
1443 #else
1444 (void)::poll(NULL, 0, 100);
1445 #endif
1446 }
1447 } else {
1448 jio_fprintf(stderr,
1449 "Could not open pause file '%s', continuing immediately.\n", filename);
1450 }
1451 }
1452
1453 static const char* errno_to_string (int e, bool short_text) {
1454 #define ALL_SHARED_ENUMS(X) \
1455 X(E2BIG, "Argument list too long") \
1456 X(EACCES, "Permission denied") \
1457 X(EADDRINUSE, "Address in use") \
1458 X(EADDRNOTAVAIL, "Address not available") \
1459 X(EAFNOSUPPORT, "Address family not supported") \
1460 X(EAGAIN, "Resource unavailable, try again") \
1461 X(EALREADY, "Connection already in progress") \
1462 X(EBADF, "Bad file descriptor") \
1463 X(EBADMSG, "Bad message") \
1464 X(EBUSY, "Device or resource busy") \
1465 X(ECANCELED, "Operation canceled") \
1466 X(ECHILD, "No child processes") \
1467 X(ECONNABORTED, "Connection aborted") \
1468 X(ECONNREFUSED, "Connection refused") \
1469 X(ECONNRESET, "Connection reset") \
1470 X(EDEADLK, "Resource deadlock would occur") \
1471 X(EDESTADDRREQ, "Destination address required") \
1472 X(EDOM, "Mathematics argument out of domain of function") \
1473 X(EEXIST, "File exists") \
1474 X(EFAULT, "Bad address") \
1475 X(EFBIG, "File too large") \
1476 X(EHOSTUNREACH, "Host is unreachable") \
1477 X(EIDRM, "Identifier removed") \
1478 X(EILSEQ, "Illegal byte sequence") \
1479 X(EINPROGRESS, "Operation in progress") \
1480 X(EINTR, "Interrupted function") \
1481 X(EINVAL, "Invalid argument") \
1482 X(EIO, "I/O error") \
1483 X(EISCONN, "Socket is connected") \
1484 X(EISDIR, "Is a directory") \
1485 X(ELOOP, "Too many levels of symbolic links") \
1486 X(EMFILE, "Too many open files") \
1487 X(EMLINK, "Too many links") \
1488 X(EMSGSIZE, "Message too large") \
1489 X(ENAMETOOLONG, "Filename too long") \
1490 X(ENETDOWN, "Network is down") \
1491 X(ENETRESET, "Connection aborted by network") \
1492 X(ENETUNREACH, "Network unreachable") \
1493 X(ENFILE, "Too many files open in system") \
1494 X(ENOBUFS, "No buffer space available") \
1495 X(ENODATA, "No message is available on the STREAM head read queue") \
1496 X(ENODEV, "No such device") \
1497 X(ENOENT, "No such file or directory") \
1498 X(ENOEXEC, "Executable file format error") \
1499 X(ENOLCK, "No locks available") \
1500 X(ENOLINK, "Reserved") \
1501 X(ENOMEM, "Not enough space") \
1502 X(ENOMSG, "No message of the desired type") \
1503 X(ENOPROTOOPT, "Protocol not available") \
1504 X(ENOSPC, "No space left on device") \
1505 X(ENOSR, "No STREAM resources") \
1506 X(ENOSTR, "Not a STREAM") \
1507 X(ENOSYS, "Function not supported") \
1508 X(ENOTCONN, "The socket is not connected") \
1509 X(ENOTDIR, "Not a directory") \
1510 X(ENOTEMPTY, "Directory not empty") \
1511 X(ENOTSOCK, "Not a socket") \
1512 X(ENOTSUP, "Not supported") \
1513 X(ENOTTY, "Inappropriate I/O control operation") \
1514 X(ENXIO, "No such device or address") \
1515 X(EOPNOTSUPP, "Operation not supported on socket") \
1516 X(EOVERFLOW, "Value too large to be stored in data type") \
1517 X(EPERM, "Operation not permitted") \
1518 X(EPIPE, "Broken pipe") \
1519 X(EPROTO, "Protocol error") \
1520 X(EPROTONOSUPPORT, "Protocol not supported") \
1521 X(EPROTOTYPE, "Protocol wrong type for socket") \
1522 X(ERANGE, "Result too large") \
1523 X(EROFS, "Read-only file system") \
1524 X(ESPIPE, "Invalid seek") \
1525 X(ESRCH, "No such process") \
1526 X(ETIME, "Stream ioctl() timeout") \
1527 X(ETIMEDOUT, "Connection timed out") \
1528 X(ETXTBSY, "Text file busy") \
1529 X(EWOULDBLOCK, "Operation would block") \
1530 X(EXDEV, "Cross-device link")
1531
1532 #define DEFINE_ENTRY(e, text) { e, #e, text },
1533
1534 static const struct {
1535 int v;
1536 const char* short_text;
1537 const char* long_text;
1538 } table [] = {
1539
1540 ALL_SHARED_ENUMS(DEFINE_ENTRY)
1541
1542 // The following enums are not defined on all platforms.
1543 #ifdef ESTALE
1544 DEFINE_ENTRY(ESTALE, "Reserved")
1545 #endif
1546 #ifdef EDQUOT
1547 DEFINE_ENTRY(EDQUOT, "Reserved")
1548 #endif
1549 #ifdef EMULTIHOP
1550 DEFINE_ENTRY(EMULTIHOP, "Reserved")
1551 #endif
1552
1553 // End marker.
1554 { -1, "Unknown errno", "Unknown error" }
1555
1556 };
1557
1558 #undef DEFINE_ENTRY
1559 #undef ALL_FLAGS
1560
1561 int i = 0;
1562 while (table[i].v != -1 && table[i].v != e) {
1563 i ++;
1564 }
1565
1566 return short_text ? table[i].short_text : table[i].long_text;
1567
1568 }
1569
1570 const char* os::strerror(int e) {
1571 return errno_to_string(e, false);
1572 }
1573
1574 const char* os::errno_name(int e) {
1575 return errno_to_string(e, true);
1576 }
1577
1578 #define trace_page_size_params(size) byte_size_in_exact_unit(size), exact_unit_for_byte_size(size)
1579
1580 void os::trace_page_sizes(const char* str,
1581 const size_t region_min_size,
1582 const size_t region_max_size,
1583 const size_t page_size,
1584 const char* base,
1585 const size_t size) {
1586
1587 log_info(pagesize)("%s: "
1588 " min=" SIZE_FORMAT "%s"
1589 " max=" SIZE_FORMAT "%s"
1590 " base=" PTR_FORMAT
1591 " page_size=" SIZE_FORMAT "%s"
1592 " size=" SIZE_FORMAT "%s",
1593 str,
1594 trace_page_size_params(region_min_size),
1595 trace_page_size_params(region_max_size),
1596 p2i(base),
1597 trace_page_size_params(page_size),
1598 trace_page_size_params(size));
1599 }
1600
1601 void os::trace_page_sizes_for_requested_size(const char* str,
1602 const size_t requested_size,
1603 const size_t page_size,
1604 const size_t alignment,
1605 const char* base,
1606 const size_t size) {
1607
1608 log_info(pagesize)("%s:"
1609 " req_size=" SIZE_FORMAT "%s"
1610 " base=" PTR_FORMAT
1611 " page_size=" SIZE_FORMAT "%s"
1612 " alignment=" SIZE_FORMAT "%s"
1613 " size=" SIZE_FORMAT "%s",
1614 str,
1615 trace_page_size_params(requested_size),
1616 p2i(base),
1617 trace_page_size_params(page_size),
1618 trace_page_size_params(alignment),
1619 trace_page_size_params(size));
1620 }
1621
1622
1623 // This is the working definition of a server class machine:
1624 // >= 2 physical CPU's and >=2GB of memory, with some fuzz
1625 // because the graphics memory (?) sometimes masks physical memory.
1626 // If you want to change the definition of a server class machine
1627 // on some OS or platform, e.g., >=4GB on Windows platforms,
1628 // then you'll have to parameterize this method based on that state,
1629 // as was done for logical processors here, or replicate and
1630 // specialize this method for each platform. (Or fix os to have
1631 // some inheritance structure and use subclassing. Sigh.)
1632 // If you want some platform to always or never behave as a server
1633 // class machine, change the setting of AlwaysActAsServerClassMachine
1634 // and NeverActAsServerClassMachine in globals*.hpp.
1635 bool os::is_server_class_machine() {
1636 // First check for the early returns
1637 if (NeverActAsServerClassMachine) {
1638 return false;
1639 }
1640 if (AlwaysActAsServerClassMachine) {
1641 return true;
1642 }
1643 // Then actually look at the machine
1644 bool result = false;
1645 const unsigned int server_processors = 2;
1646 const julong server_memory = 2UL * G;
1647 // We seem not to get our full complement of memory.
1648 // We allow some part (1/8?) of the memory to be "missing",
1649 // based on the sizes of DIMMs, and maybe graphics cards.
1650 const julong missing_memory = 256UL * M;
1651
1652 /* Is this a server class machine? */
1653 if ((os::active_processor_count() >= (int)server_processors) &&
1654 (os::physical_memory() >= (server_memory - missing_memory))) {
1655 const unsigned int logical_processors =
1656 VM_Version::logical_processors_per_package();
1657 if (logical_processors > 1) {
1658 const unsigned int physical_packages =
1659 os::active_processor_count() / logical_processors;
1660 if (physical_packages >= server_processors) {
1661 result = true;
1662 }
1663 } else {
1664 result = true;
1665 }
1666 }
1667 return result;
1668 }
1669
1670 void os::initialize_initial_active_processor_count() {
1671 assert(_initial_active_processor_count == 0, "Initial active processor count already set.");
1672 _initial_active_processor_count = active_processor_count();
1673 log_debug(os)("Initial active processor count set to %d" , _initial_active_processor_count);
1674 }
1675
1676 void os::SuspendedThreadTask::run() {
1677 internal_do_task();
1678 _done = true;
1679 }
1680
1681 bool os::create_stack_guard_pages(char* addr, size_t bytes) {
1682 return os::pd_create_stack_guard_pages(addr, bytes);
1683 }
1684
1685 char* os::reserve_memory(size_t bytes, bool executable, MEMFLAGS flags) {
1686 char* result = pd_reserve_memory(bytes, executable);
1687 if (result != NULL) {
1688 MemTracker::record_virtual_memory_reserve(result, bytes, CALLER_PC);
1689 if (flags != mtOther) {
1690 MemTracker::record_virtual_memory_type(result, flags);
1691 }
1692 }
1693
1694 return result;
1695 }
1696
1697 char* os::attempt_reserve_memory_at(char* addr, size_t bytes, bool executable) {
1698 char* result = pd_attempt_reserve_memory_at(addr, bytes, executable);
1699 if (result != NULL) {
1700 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1701 } else {
1702 log_debug(os)("Attempt to reserve memory at " INTPTR_FORMAT " for "
1703 SIZE_FORMAT " bytes failed, errno %d", p2i(addr), bytes, get_last_error());
1704 }
1705 return result;
1706 }
1707
1708 static void assert_nonempty_range(const char* addr, size_t bytes) {
1709 assert(addr != nullptr && bytes > 0, "invalid range [" PTR_FORMAT ", " PTR_FORMAT ")",
1710 p2i(addr), p2i(addr) + bytes);
1711 }
1712
1713 bool os::commit_memory(char* addr, size_t bytes, bool executable) {
1714 assert_nonempty_range(addr, bytes);
1715 bool res = pd_commit_memory(addr, bytes, executable);
1716 if (res) {
1717 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1718 }
1719 return res;
1720 }
1721
1722 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint,
1723 bool executable) {
1724 assert_nonempty_range(addr, size);
1725 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable);
1726 if (res) {
1727 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1728 }
1729 return res;
1730 }
1731
1732 void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable,
1733 const char* mesg) {
1734 assert_nonempty_range(addr, bytes);
1735 pd_commit_memory_or_exit(addr, bytes, executable, mesg);
1736 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1737 }
1738
1739 void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint,
1740 bool executable, const char* mesg) {
1741 assert_nonempty_range(addr, size);
1742 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg);
1743 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1744 }
1745
1746 bool os::uncommit_memory(char* addr, size_t bytes, bool executable) {
1747 assert_nonempty_range(addr, bytes);
1748 bool res;
1749 if (MemTracker::enabled()) {
1750 Tracker tkr(Tracker::uncommit);
1751 res = pd_uncommit_memory(addr, bytes, executable);
1752 if (res) {
1753 tkr.record((address)addr, bytes);
1754 }
1755 } else {
1756 res = pd_uncommit_memory(addr, bytes, executable);
1757 }
1758 return res;
1759 }
1760
1761 bool os::release_memory(char* addr, size_t bytes) {
1762 assert_nonempty_range(addr, bytes);
1763 bool res;
1764 if (MemTracker::enabled()) {
1765 // Note: Tracker contains a ThreadCritical.
1766 Tracker tkr(Tracker::release);
1767 res = pd_release_memory(addr, bytes);
1768 if (res) {
1769 tkr.record((address)addr, bytes);
1770 }
1771 } else {
1772 res = pd_release_memory(addr, bytes);
1773 }
1774 if (!res) {
1775 log_info(os)("os::release_memory failed (" PTR_FORMAT ", " SIZE_FORMAT ")", p2i(addr), bytes);
1776 }
1777 return res;
1778 }
1779
1780 // Prints all mappings
1781 void os::print_memory_mappings(outputStream* st) {
1782 os::print_memory_mappings(nullptr, (size_t)-1, st);
1783 }
1784
1785 // Pretouching must use a store, not just a load. On many OSes loads from
1786 // fresh memory would be satisfied from a single mapped page containing all
1787 // zeros. We need to store something to each page to get them backed by
1788 // their own memory, which is the effect we want here. An atomic add of
1789 // zero is used instead of a simple store, allowing the memory to be used
1790 // while pretouch is in progress, rather than requiring users of the memory
1791 // to wait until the entire range has been touched. This is technically
1792 // a UB data race, but doesn't cause any problems for us.
1793 void os::pretouch_memory(void* start, void* end, size_t page_size) {
1794 assert(start <= end, "invalid range: " PTR_FORMAT " -> " PTR_FORMAT, p2i(start), p2i(end));
1795 assert(is_power_of_2(page_size), "page size misaligned: %zu", page_size);
1796 assert(page_size >= sizeof(int), "page size too small: %zu", page_size);
1797 if (start < end) {
1798 // We're doing concurrent-safe touch and memory state has page
1799 // granularity, so we can touch anywhere in a page. Touch at the
1800 // beginning of each page to simplify iteration.
1801 char* cur = static_cast<char*>(align_down(start, page_size));
1802 void* last = align_down(static_cast<char*>(end) - 1, page_size);
1803 assert(cur <= last, "invariant");
1804 // Iterate from first page through last (inclusive), being careful to
1805 // avoid overflow if the last page abuts the end of the address range.
1806 for ( ; true; cur += page_size) {
1807 Atomic::add(reinterpret_cast<int*>(cur), 0, memory_order_relaxed);
1808 if (cur >= last) break;
1809 }
1810 }
1811 }
1812
1813 char* os::map_memory_to_file(size_t bytes, int file_desc) {
1814 // Could have called pd_reserve_memory() followed by replace_existing_mapping_with_file_mapping(),
1815 // but AIX may use SHM in which case its more trouble to detach the segment and remap memory to the file.
1816 // On all current implementations NULL is interpreted as any available address.
1817 char* result = os::map_memory_to_file(NULL /* addr */, bytes, file_desc);
1818 if (result != NULL) {
1819 MemTracker::record_virtual_memory_reserve_and_commit(result, bytes, CALLER_PC);
1820 }
1821 return result;
1822 }
1823
1824 char* os::attempt_map_memory_to_file_at(char* addr, size_t bytes, int file_desc) {
1825 char* result = pd_attempt_map_memory_to_file_at(addr, bytes, file_desc);
1826 if (result != NULL) {
1827 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC);
1828 }
1829 return result;
1830 }
1831
1832 char* os::map_memory(int fd, const char* file_name, size_t file_offset,
1833 char *addr, size_t bytes, bool read_only,
1834 bool allow_exec, MEMFLAGS flags) {
1835 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec);
1836 if (result != NULL) {
1837 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC, flags);
1838 }
1839 return result;
1840 }
1841
1842 char* os::remap_memory(int fd, const char* file_name, size_t file_offset,
1843 char *addr, size_t bytes, bool read_only,
1844 bool allow_exec) {
1845 return pd_remap_memory(fd, file_name, file_offset, addr, bytes,
1846 read_only, allow_exec);
1847 }
1848
1849 bool os::unmap_memory(char *addr, size_t bytes) {
1850 bool result;
1851 if (MemTracker::enabled()) {
1852 Tracker tkr(Tracker::release);
1853 result = pd_unmap_memory(addr, bytes);
1854 if (result) {
1855 tkr.record((address)addr, bytes);
1856 }
1857 } else {
1858 result = pd_unmap_memory(addr, bytes);
1859 }
1860 return result;
1861 }
1862
1863 void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) {
1864 pd_free_memory(addr, bytes, alignment_hint);
1865 }
1866
1867 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
1868 pd_realign_memory(addr, bytes, alignment_hint);
1869 }
1870
1871 char* os::reserve_memory_special(size_t size, size_t alignment, size_t page_size,
1872 char* addr, bool executable) {
1873
1874 assert(is_aligned(addr, alignment), "Unaligned request address");
1875
1876 char* result = pd_reserve_memory_special(size, alignment, page_size, addr, executable);
1877 if (result != NULL) {
1878 // The memory is committed
1879 MemTracker::record_virtual_memory_reserve_and_commit((address)result, size, CALLER_PC);
1880 }
1881
1882 return result;
1883 }
1884
1885 bool os::release_memory_special(char* addr, size_t bytes) {
1886 bool res;
1887 if (MemTracker::enabled()) {
1888 // Note: Tracker contains a ThreadCritical.
1889 Tracker tkr(Tracker::release);
1890 res = pd_release_memory_special(addr, bytes);
1891 if (res) {
1892 tkr.record((address)addr, bytes);
1893 }
1894 } else {
1895 res = pd_release_memory_special(addr, bytes);
1896 }
1897 return res;
1898 }
1899
1900 #ifndef _WINDOWS
1901 /* try to switch state from state "from" to state "to"
1902 * returns the state set after the method is complete
1903 */
1904 os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from,
1905 os::SuspendResume::State to)
1906 {
1907 os::SuspendResume::State result = Atomic::cmpxchg(&_state, from, to);
1908 if (result == from) {
1909 // success
1910 return to;
1911 }
1912 return result;
1913 }
1914 #endif
1915
1916 // Convenience wrapper around naked_short_sleep to allow for longer sleep
1917 // times. Only for use by non-JavaThreads.
1918 void os::naked_sleep(jlong millis) {
1919 assert(!Thread::current()->is_Java_thread(), "not for use by JavaThreads");
1920 const jlong limit = 999;
1921 while (millis > limit) {
1922 naked_short_sleep(limit);
1923 millis -= limit;
1924 }
1925 naked_short_sleep(millis);
1926 }
1927
1928
1929 ////// Implementation of PageSizes
1930
1931 void os::PageSizes::add(size_t page_size) {
1932 assert(is_power_of_2(page_size), "page_size must be a power of 2: " SIZE_FORMAT_HEX, page_size);
1933 _v |= page_size;
1934 }
1935
1936 bool os::PageSizes::contains(size_t page_size) const {
1937 assert(is_power_of_2(page_size), "page_size must be a power of 2: " SIZE_FORMAT_HEX, page_size);
1938 return (_v & page_size) != 0;
1939 }
1940
1941 size_t os::PageSizes::next_smaller(size_t page_size) const {
1942 assert(is_power_of_2(page_size), "page_size must be a power of 2: " SIZE_FORMAT_HEX, page_size);
1943 size_t v2 = _v & (page_size - 1);
1944 if (v2 == 0) {
1945 return 0;
1946 }
1947 return round_down_power_of_2(v2);
1948 }
1949
1950 size_t os::PageSizes::next_larger(size_t page_size) const {
1951 assert(is_power_of_2(page_size), "page_size must be a power of 2: " SIZE_FORMAT_HEX, page_size);
1952 if (page_size == max_power_of_2<size_t>()) { // Shift by 32/64 would be UB
1953 return 0;
1954 }
1955 // Remove current and smaller page sizes
1956 size_t v2 = _v & ~(page_size + (page_size - 1));
1957 if (v2 == 0) {
1958 return 0;
1959 }
1960 return (size_t)1 << count_trailing_zeros(v2);
1961 }
1962
1963 size_t os::PageSizes::largest() const {
1964 const size_t max = max_power_of_2<size_t>();
1965 if (contains(max)) {
1966 return max;
1967 }
1968 return next_smaller(max);
1969 }
1970
1971 size_t os::PageSizes::smallest() const {
1972 // Strictly speaking the set should not contain sizes < os::vm_page_size().
1973 // But this is not enforced.
1974 return next_larger(1);
1975 }
1976
1977 void os::PageSizes::print_on(outputStream* st) const {
1978 bool first = true;
1979 for (size_t sz = smallest(); sz != 0; sz = next_larger(sz)) {
1980 if (first) {
1981 first = false;
1982 } else {
1983 st->print_raw(", ");
1984 }
1985 if (sz < M) {
1986 st->print(SIZE_FORMAT "k", sz / K);
1987 } else if (sz < G) {
1988 st->print(SIZE_FORMAT "M", sz / M);
1989 } else {
1990 st->print(SIZE_FORMAT "G", sz / G);
1991 }
1992 }
1993 if (first) {
1994 st->print("empty");
1995 }
1996 }