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/javaThread.hpp"
55 #include "runtime/jniHandles.hpp"
56 #include "runtime/mutexLocker.hpp"
57 #include "runtime/os.inline.hpp"
58 #include "runtime/osThread.hpp"
59 #include "runtime/safefetch.hpp"
60 #include "runtime/sharedRuntime.hpp"
61 #include "runtime/threadCrashProtection.hpp"
62 #include "runtime/threadSMR.hpp"
63 #include "runtime/vmOperations.hpp"
64 #include "runtime/vm_version.hpp"
65 #include "services/attachListener.hpp"
66 #include "services/mallocTracker.hpp"
67 #include "services/memTracker.hpp"
68 #include "services/nmtPreInit.hpp"
69 #include "services/nmtCommon.hpp"
70 #include "services/threadService.hpp"
71 #include "utilities/align.hpp"
72 #include "utilities/count_trailing_zeros.hpp"
73 #include "utilities/defaultStream.hpp"
74 #include "utilities/events.hpp"
75 #include "utilities/powerOfTwo.hpp"
76
77 #ifndef _WINDOWS
78 # include <poll.h>
79 #endif
80
81 # include <signal.h>
82 # include <errno.h>
83
84 OSThread* os::_starting_thread = NULL;
85 address os::_polling_page = NULL;
86 volatile unsigned int os::_rand_seed = 1234567;
87 int os::_processor_count = 0;
88 int os::_initial_active_processor_count = 0;
89 os::PageSizes os::_page_sizes;
90
91 static size_t cur_malloc_words = 0; // current size for MallocMaxTestWords
92
93 DEBUG_ONLY(bool os::_mutex_init_done = false;)
94
95 int os::snprintf(char* buf, size_t len, const char* fmt, ...) {
96 va_list args;
97 va_start(args, fmt);
98 int result = os::vsnprintf(buf, len, fmt, args);
99 va_end(args);
100 return result;
101 }
102
103 // Fill in buffer with current local time as an ISO-8601 string.
104 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz.
105 // Returns buffer, or NULL if it failed.
106 char* os::iso8601_time(char* buffer, size_t buffer_length, bool utc) {
107 const jlong now = javaTimeMillis();
108 return os::iso8601_time(now, buffer, buffer_length, utc);
109 }
110
111 // Fill in buffer with an ISO-8601 string corresponding to the given javaTimeMillis value
112 // E.g., yyyy-mm-ddThh:mm:ss-zzzz.
113 // Returns buffer, or NULL if it failed.
114 // This would mostly be a call to
115 // strftime(...., "%Y-%m-%d" "T" "%H:%M:%S" "%z", ....)
116 // except that on Windows the %z behaves badly, so we do it ourselves.
117 // Also, people wanted milliseconds on there,
118 // and strftime doesn't do milliseconds.
119 char* os::iso8601_time(jlong milliseconds_since_19700101, char* buffer, size_t buffer_length, bool utc) {
120 // Output will be of the form "YYYY-MM-DDThh:mm:ss.mmm+zzzz\0"
121
122 // Sanity check the arguments
123 if (buffer == NULL) {
124 assert(false, "NULL buffer");
125 return NULL;
126 }
127 if (buffer_length < os::iso8601_timestamp_size) {
128 assert(false, "buffer_length too small");
129 return NULL;
130 }
131 const int milliseconds_per_microsecond = 1000;
132 const time_t seconds_since_19700101 =
133 milliseconds_since_19700101 / milliseconds_per_microsecond;
134 const int milliseconds_after_second =
135 milliseconds_since_19700101 % milliseconds_per_microsecond;
136 // Convert the time value to a tm and timezone variable
137 struct tm time_struct;
138 if (utc) {
139 if (gmtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
140 assert(false, "Failed gmtime_pd");
141 return NULL;
142 }
143 } else {
144 if (localtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
145 assert(false, "Failed localtime_pd");
146 return NULL;
147 }
148 }
149
150 const time_t seconds_per_minute = 60;
151 const time_t minutes_per_hour = 60;
152 const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour;
153
154 // No offset when dealing with UTC
155 time_t UTC_to_local = 0;
156 if (!utc) {
157 #if defined(_ALLBSD_SOURCE) || defined(_GNU_SOURCE)
158 UTC_to_local = -(time_struct.tm_gmtoff);
159 #elif defined(_WINDOWS)
160 long zone;
161 _get_timezone(&zone);
162 UTC_to_local = static_cast<time_t>(zone);
163 #else
164 UTC_to_local = timezone;
165 #endif
166
167 // tm_gmtoff already includes adjustment for daylight saving
168 #if !defined(_ALLBSD_SOURCE) && !defined(_GNU_SOURCE)
169 // If daylight savings time is in effect,
170 // we are 1 hour East of our time zone
171 if (time_struct.tm_isdst > 0) {
172 UTC_to_local = UTC_to_local - seconds_per_hour;
173 }
174 #endif
175 }
176
177 // Compute the time zone offset.
178 // localtime_pd() sets timezone to the difference (in seconds)
179 // between UTC and and local time.
180 // ISO 8601 says we need the difference between local time and UTC,
181 // we change the sign of the localtime_pd() result.
182 const time_t local_to_UTC = -(UTC_to_local);
183 // Then we have to figure out if if we are ahead (+) or behind (-) UTC.
184 char sign_local_to_UTC = '+';
185 time_t abs_local_to_UTC = local_to_UTC;
186 if (local_to_UTC < 0) {
187 sign_local_to_UTC = '-';
188 abs_local_to_UTC = -(abs_local_to_UTC);
189 }
190 // Convert time zone offset seconds to hours and minutes.
191 const time_t zone_hours = (abs_local_to_UTC / seconds_per_hour);
192 const time_t zone_min =
193 ((abs_local_to_UTC % seconds_per_hour) / seconds_per_minute);
194
195 // Print an ISO 8601 date and time stamp into the buffer
196 const int year = 1900 + time_struct.tm_year;
197 const int month = 1 + time_struct.tm_mon;
198 const int printed = jio_snprintf(buffer, buffer_length,
199 "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d",
200 year,
201 month,
202 time_struct.tm_mday,
203 time_struct.tm_hour,
204 time_struct.tm_min,
205 time_struct.tm_sec,
206 milliseconds_after_second,
207 sign_local_to_UTC,
208 zone_hours,
209 zone_min);
210 if (printed == 0) {
211 assert(false, "Failed jio_printf");
212 return NULL;
213 }
214 return buffer;
215 }
216
217 OSReturn os::set_priority(Thread* thread, ThreadPriority p) {
218 debug_only(Thread::check_for_dangling_thread_pointer(thread);)
219
220 if ((p >= MinPriority && p <= MaxPriority) ||
221 (p == CriticalPriority && thread->is_ConcurrentGC_thread())) {
222 int priority = java_to_os_priority[p];
223 return set_native_priority(thread, priority);
224 } else {
225 assert(false, "Should not happen");
226 return OS_ERR;
227 }
228 }
229
230 // The mapping from OS priority back to Java priority may be inexact because
231 // Java priorities can map M:1 with native priorities. If you want the definite
232 // Java priority then use JavaThread::java_priority()
233 OSReturn os::get_priority(const Thread* const thread, ThreadPriority& priority) {
234 int p;
235 int os_prio;
236 OSReturn ret = get_native_priority(thread, &os_prio);
237 if (ret != OS_OK) return ret;
238
239 if (java_to_os_priority[MaxPriority] > java_to_os_priority[MinPriority]) {
240 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] > os_prio; p--) ;
241 } else {
242 // niceness values are in reverse order
243 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] < os_prio; p--) ;
244 }
245 priority = (ThreadPriority)p;
246 return OS_OK;
247 }
248
249 bool os::dll_build_name(char* buffer, size_t size, const char* fname) {
250 int n = jio_snprintf(buffer, size, "%s%s%s", JNI_LIB_PREFIX, fname, JNI_LIB_SUFFIX);
251 return (n != -1);
252 }
253
254 #if !defined(LINUX) && !defined(_WINDOWS)
255 bool os::committed_in_range(address start, size_t size, address& committed_start, size_t& committed_size) {
256 committed_start = start;
257 committed_size = size;
258 return true;
259 }
260 #endif
261
262 // Helper for dll_locate_lib.
263 // Pass buffer and printbuffer as we already printed the path to buffer
264 // when we called get_current_directory. This way we avoid another buffer
265 // of size MAX_PATH.
266 static bool conc_path_file_and_check(char *buffer, char *printbuffer, size_t printbuflen,
267 const char* pname, char lastchar, const char* fname) {
268
269 // Concatenate path and file name, but don't print double path separators.
270 const char *filesep = (WINDOWS_ONLY(lastchar == ':' ||) lastchar == os::file_separator()[0]) ?
271 "" : os::file_separator();
272 int ret = jio_snprintf(printbuffer, printbuflen, "%s%s%s", pname, filesep, fname);
273 // Check whether file exists.
274 if (ret != -1) {
275 struct stat statbuf;
276 return os::stat(buffer, &statbuf) == 0;
277 }
278 return false;
279 }
280
281 // Frees all memory allocated on the heap for the
282 // supplied array of arrays of chars (a), where n
283 // is the number of elements in the array.
284 static void free_array_of_char_arrays(char** a, size_t n) {
285 while (n > 0) {
286 n--;
287 if (a[n] != NULL) {
288 FREE_C_HEAP_ARRAY(char, a[n]);
289 }
290 }
291 FREE_C_HEAP_ARRAY(char*, a);
292 }
293
294 bool os::dll_locate_lib(char *buffer, size_t buflen,
295 const char* pname, const char* fname) {
296 bool retval = false;
297
298 size_t fullfnamelen = strlen(JNI_LIB_PREFIX) + strlen(fname) + strlen(JNI_LIB_SUFFIX);
299 char* fullfname = NEW_C_HEAP_ARRAY(char, fullfnamelen + 1, mtInternal);
300 if (dll_build_name(fullfname, fullfnamelen + 1, fname)) {
301 const size_t pnamelen = pname ? strlen(pname) : 0;
302
303 if (pnamelen == 0) {
304 // If no path given, use current working directory.
305 const char* p = get_current_directory(buffer, buflen);
306 if (p != NULL) {
307 const size_t plen = strlen(buffer);
308 const char lastchar = buffer[plen - 1];
309 retval = conc_path_file_and_check(buffer, &buffer[plen], buflen - plen,
310 "", lastchar, fullfname);
311 }
312 } else if (strchr(pname, *os::path_separator()) != NULL) {
313 // A list of paths. Search for the path that contains the library.
314 size_t n;
315 char** pelements = split_path(pname, &n, fullfnamelen);
316 if (pelements != NULL) {
317 for (size_t i = 0; i < n; i++) {
318 char* path = pelements[i];
319 // Really shouldn't be NULL, but check can't hurt.
320 size_t plen = (path == NULL) ? 0 : strlen(path);
321 if (plen == 0) {
322 continue; // Skip the empty path values.
323 }
324 const char lastchar = path[plen - 1];
325 retval = conc_path_file_and_check(buffer, buffer, buflen, path, lastchar, fullfname);
326 if (retval) break;
327 }
328 // Release the storage allocated by split_path.
329 free_array_of_char_arrays(pelements, n);
330 }
331 } else {
332 // A definite path.
333 const char lastchar = pname[pnamelen-1];
334 retval = conc_path_file_and_check(buffer, buffer, buflen, pname, lastchar, fullfname);
335 }
336 }
337
338 FREE_C_HEAP_ARRAY(char*, fullfname);
339 return retval;
340 }
341
342 // --------------------- sun.misc.Signal (optional) ---------------------
343
344
345 // SIGBREAK is sent by the keyboard to query the VM state
346 #ifndef SIGBREAK
347 #define SIGBREAK SIGQUIT
348 #endif
349
350 // sigexitnum_pd is a platform-specific special signal used for terminating the Signal thread.
351
352
353 static void signal_thread_entry(JavaThread* thread, TRAPS) {
354 os::set_priority(thread, NearMaxPriority);
355 while (true) {
356 int sig;
357 {
358 // FIXME : Currently we have not decided what should be the status
359 // for this java thread blocked here. Once we decide about
360 // that we should fix this.
361 sig = os::signal_wait();
362 }
363 if (sig == os::sigexitnum_pd()) {
364 // Terminate the signal thread
365 return;
366 }
367
368 switch (sig) {
369 case SIGBREAK: {
370 #if INCLUDE_SERVICES
371 // Check if the signal is a trigger to start the Attach Listener - in that
372 // case don't print stack traces.
373 if (!DisableAttachMechanism) {
374 // Attempt to transit state to AL_INITIALIZING.
375 AttachListenerState cur_state = AttachListener::transit_state(AL_INITIALIZING, AL_NOT_INITIALIZED);
376 if (cur_state == AL_INITIALIZING) {
377 // Attach Listener has been started to initialize. Ignore this signal.
378 continue;
379 } else if (cur_state == AL_NOT_INITIALIZED) {
380 // Start to initialize.
381 if (AttachListener::is_init_trigger()) {
382 // Attach Listener has been initialized.
383 // Accept subsequent request.
384 continue;
385 } else {
386 // Attach Listener could not be started.
387 // So we need to transit the state to AL_NOT_INITIALIZED.
388 AttachListener::set_state(AL_NOT_INITIALIZED);
389 }
390 } else if (AttachListener::check_socket_file()) {
391 // Attach Listener has been started, but unix domain socket file
392 // does not exist. So restart Attach Listener.
393 continue;
394 }
395 }
396 #endif
397 // Print stack traces
398 // Any SIGBREAK operations added here should make sure to flush
399 // the output stream (e.g. tty->flush()) after output. See 4803766.
400 // Each module also prints an extra carriage return after its output.
401 VM_PrintThreads op(tty, PrintConcurrentLocks, false /* no extended info */, true /* print JNI handle info */);
402 VMThread::execute(&op);
403 VM_FindDeadlocks op1(tty);
404 VMThread::execute(&op1);
405 Universe::print_heap_at_SIGBREAK();
406 if (PrintClassHistogram) {
407 VM_GC_HeapInspection op1(tty, true /* force full GC before heap inspection */);
408 VMThread::execute(&op1);
409 }
410 if (JvmtiExport::should_post_data_dump()) {
411 JvmtiExport::post_data_dump();
412 }
413 break;
414 }
415 default: {
416 // Dispatch the signal to java
417 HandleMark hm(THREAD);
418 Klass* klass = SystemDictionary::resolve_or_null(vmSymbols::jdk_internal_misc_Signal(), THREAD);
419 if (klass != NULL) {
420 JavaValue result(T_VOID);
421 JavaCallArguments args;
422 args.push_int(sig);
423 JavaCalls::call_static(
424 &result,
425 klass,
426 vmSymbols::dispatch_name(),
427 vmSymbols::int_void_signature(),
428 &args,
429 THREAD
430 );
431 }
432 if (HAS_PENDING_EXCEPTION) {
433 // tty is initialized early so we don't expect it to be null, but
434 // if it is we can't risk doing an initialization that might
435 // trigger additional out-of-memory conditions
436 if (tty != NULL) {
437 char klass_name[256];
438 char tmp_sig_name[16];
439 const char* sig_name = "UNKNOWN";
440 InstanceKlass::cast(PENDING_EXCEPTION->klass())->
441 name()->as_klass_external_name(klass_name, 256);
442 if (os::exception_name(sig, tmp_sig_name, 16) != NULL)
443 sig_name = tmp_sig_name;
444 warning("Exception %s occurred dispatching signal %s to handler"
445 "- the VM may need to be forcibly terminated",
446 klass_name, sig_name );
447 }
448 CLEAR_PENDING_EXCEPTION;
449 }
450 }
451 }
452 }
453 }
454
455 void os::init_before_ergo() {
456 initialize_initial_active_processor_count();
457 // We need to initialize large page support here because ergonomics takes some
458 // decisions depending on large page support and the calculated large page size.
459 large_page_init();
460
461 StackOverflow::initialize_stack_zone_sizes();
462
463 // VM version initialization identifies some characteristics of the
464 // platform that are used during ergonomic decisions.
465 VM_Version::init_before_ergo();
466 }
467
468 void os::initialize_jdk_signal_support(TRAPS) {
469 if (!ReduceSignalUsage) {
470 // Setup JavaThread for processing signals
471 const char* name = "Signal Dispatcher";
472 Handle thread_oop = JavaThread::create_system_thread_object(name, true /* visible */, CHECK);
473
474 JavaThread* thread = new JavaThread(&signal_thread_entry);
475 JavaThread::vm_exit_on_osthread_failure(thread);
476
477 JavaThread::start_internal_daemon(THREAD, thread, thread_oop, NearMaxPriority);
478 }
479 }
480
481
482 void os::terminate_signal_thread() {
483 if (!ReduceSignalUsage)
484 signal_notify(sigexitnum_pd());
485 }
486
487
488 // --------------------- loading libraries ---------------------
489
490 typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *);
491 extern struct JavaVM_ main_vm;
492
493 static void* _native_java_library = NULL;
494
495 void* os::native_java_library() {
496 if (_native_java_library == NULL) {
497 char buffer[JVM_MAXPATHLEN];
498 char ebuf[1024];
499
500 // Load java dll
501 if (dll_locate_lib(buffer, sizeof(buffer), Arguments::get_dll_dir(),
502 "java")) {
503 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf));
504 }
505 if (_native_java_library == NULL) {
506 vm_exit_during_initialization("Unable to load native library", ebuf);
507 }
508
509 #if defined(__OpenBSD__)
510 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so
511 // ignore errors
512 if (dll_locate_lib(buffer, sizeof(buffer), Arguments::get_dll_dir(),
513 "net")) {
514 dll_load(buffer, ebuf, sizeof(ebuf));
515 }
516 #endif
517 }
518 return _native_java_library;
519 }
520
521 /*
522 * Support for finding Agent_On(Un)Load/Attach<_lib_name> if it exists.
523 * If check_lib == true then we are looking for an
524 * Agent_OnLoad_lib_name or Agent_OnAttach_lib_name function to determine if
525 * this library is statically linked into the image.
526 * If check_lib == false then we will look for the appropriate symbol in the
527 * executable if agent_lib->is_static_lib() == true or in the shared library
528 * referenced by 'handle'.
529 */
530 void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib,
531 const char *syms[], size_t syms_len) {
532 assert(agent_lib != NULL, "sanity check");
533 const char *lib_name;
534 void *handle = agent_lib->os_lib();
535 void *entryName = NULL;
536 char *agent_function_name;
537 size_t i;
538
539 // If checking then use the agent name otherwise test is_static_lib() to
540 // see how to process this lookup
541 lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL);
542 for (i = 0; i < syms_len; i++) {
543 agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path());
544 if (agent_function_name == NULL) {
545 break;
546 }
547 entryName = dll_lookup(handle, agent_function_name);
548 FREE_C_HEAP_ARRAY(char, agent_function_name);
549 if (entryName != NULL) {
550 break;
551 }
552 }
553 return entryName;
554 }
555
556 // See if the passed in agent is statically linked into the VM image.
557 bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
558 size_t syms_len) {
559 void *ret;
560 void *proc_handle;
561 void *save_handle;
562
563 assert(agent_lib != NULL, "sanity check");
564 if (agent_lib->name() == NULL) {
565 return false;
566 }
567 proc_handle = get_default_process_handle();
568 // Check for Agent_OnLoad/Attach_lib_name function
569 save_handle = agent_lib->os_lib();
570 // We want to look in this process' symbol table.
571 agent_lib->set_os_lib(proc_handle);
572 ret = find_agent_function(agent_lib, true, syms, syms_len);
573 if (ret != NULL) {
574 // Found an entry point like Agent_OnLoad_lib_name so we have a static agent
575 agent_lib->set_valid();
576 agent_lib->set_static_lib(true);
577 return true;
578 }
579 agent_lib->set_os_lib(save_handle);
580 return false;
581 }
582
583 // --------------------- heap allocation utilities ---------------------
584
585 char *os::strdup(const char *str, MEMFLAGS flags) {
586 size_t size = strlen(str);
587 char *dup_str = (char *)malloc(size + 1, flags);
588 if (dup_str == NULL) return NULL;
589 strcpy(dup_str, str);
590 return dup_str;
591 }
592
593 char* os::strdup_check_oom(const char* str, MEMFLAGS flags) {
594 char* p = os::strdup(str, flags);
595 if (p == NULL) {
596 vm_exit_out_of_memory(strlen(str) + 1, OOM_MALLOC_ERROR, "os::strdup_check_oom");
597 }
598 return p;
599 }
600
601 //
602 // This function supports testing of the malloc out of memory
603 // condition without really running the system out of memory.
604 //
605
606 static bool has_reached_max_malloc_test_peak(size_t alloc_size) {
607 if (MallocMaxTestWords > 0) {
608 size_t words = (alloc_size / BytesPerWord);
609
610 if ((cur_malloc_words + words) > MallocMaxTestWords) {
611 return true;
612 }
613 Atomic::add(&cur_malloc_words, words);
614 }
615 return false;
616 }
617
618 #ifdef ASSERT
619 static void check_crash_protection() {
620 assert(!ThreadCrashProtection::is_crash_protected(Thread::current_or_null()),
621 "not allowed when crash protection is set");
622 }
623 static void break_if_ptr_caught(void* ptr) {
624 if (p2i(ptr) == (intptr_t)MallocCatchPtr) {
625 log_warning(malloc, free)("ptr caught: " PTR_FORMAT, p2i(ptr));
626 breakpoint();
627 }
628 }
629 #endif // ASSERT
630
631 void* os::malloc(size_t size, MEMFLAGS flags) {
632 return os::malloc(size, flags, CALLER_PC);
633 }
634
635 void* os::malloc(size_t size, MEMFLAGS memflags, const NativeCallStack& stack) {
636
637 // Special handling for NMT preinit phase before arguments are parsed
638 void* rc = NULL;
639 if (NMTPreInit::handle_malloc(&rc, size)) {
640 // No need to fill with 0 because DumpSharedSpaces doesn't use these
641 // early allocations.
642 return rc;
643 }
644
645 DEBUG_ONLY(check_crash_protection());
646
647 // On malloc(0), implementations of malloc(3) have the choice to return either
648 // NULL or a unique non-NULL pointer. To unify libc behavior across our platforms
649 // we chose the latter.
650 size = MAX2((size_t)1, size);
651
652 // For the test flag -XX:MallocMaxTestWords
653 if (has_reached_max_malloc_test_peak(size)) {
654 return NULL;
655 }
656
657 const size_t outer_size = size + MemTracker::overhead_per_malloc();
658
659 ALLOW_C_FUNCTION(::malloc, void* const outer_ptr = ::malloc(outer_size);)
660 if (outer_ptr == NULL) {
661 return NULL;
662 }
663
664 void* const inner_ptr = MemTracker::record_malloc((address)outer_ptr, size, memflags, stack);
665
666 if (DumpSharedSpaces) {
667 // Need to deterministically fill all the alignment gaps in C++ structures.
668 ::memset(inner_ptr, 0, size);
669 } else {
670 DEBUG_ONLY(::memset(inner_ptr, uninitBlockPad, size);)
671 }
672 DEBUG_ONLY(break_if_ptr_caught(inner_ptr);)
673 return inner_ptr;
674 }
675
676 void* os::realloc(void *memblock, size_t size, MEMFLAGS flags) {
677 return os::realloc(memblock, size, flags, CALLER_PC);
678 }
679
680 void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, const NativeCallStack& stack) {
681
682 // Special handling for NMT preinit phase before arguments are parsed
683 void* rc = NULL;
684 if (NMTPreInit::handle_realloc(&rc, memblock, size)) {
685 return rc;
686 }
687
688 if (memblock == NULL) {
689 return os::malloc(size, memflags, stack);
690 }
691
692 DEBUG_ONLY(check_crash_protection());
693
694 // On realloc(p, 0), implementers of realloc(3) have the choice to return either
695 // NULL or a unique non-NULL pointer. To unify libc behavior across our platforms
696 // we chose the latter.
697 size = MAX2((size_t)1, size);
698
699 // For the test flag -XX:MallocMaxTestWords
700 if (has_reached_max_malloc_test_peak(size)) {
701 return NULL;
702 }
703
704 const size_t new_outer_size = size + MemTracker::overhead_per_malloc();
705
706 // If NMT is enabled, this checks for heap overwrites, then de-accounts the old block.
707 void* const old_outer_ptr = MemTracker::record_free(memblock);
708
709 ALLOW_C_FUNCTION(::realloc, void* const new_outer_ptr = ::realloc(old_outer_ptr, new_outer_size);)
710 if (new_outer_ptr == NULL) {
711 return NULL;
712 }
713
714 void* const new_inner_ptr = MemTracker::record_malloc(new_outer_ptr, size, memflags, stack);
715
716 DEBUG_ONLY(break_if_ptr_caught(new_inner_ptr);)
717
718 return new_inner_ptr;
719 }
720
721 void os::free(void *memblock) {
722
723 // Special handling for NMT preinit phase before arguments are parsed
724 if (NMTPreInit::handle_free(memblock)) {
725 return;
726 }
727
728 if (memblock == NULL) {
729 return;
730 }
731
732 DEBUG_ONLY(break_if_ptr_caught(memblock);)
733
734 // If NMT is enabled, this checks for heap overwrites, then de-accounts the old block.
735 void* const old_outer_ptr = MemTracker::record_free(memblock);
736
737 ALLOW_C_FUNCTION(::free, ::free(old_outer_ptr);)
738 }
739
740 void os::init_random(unsigned int initval) {
741 _rand_seed = initval;
742 }
743
744
745 int os::next_random(unsigned int rand_seed) {
746 /* standard, well-known linear congruential random generator with
747 * next_rand = (16807*seed) mod (2**31-1)
748 * see
749 * (1) "Random Number Generators: Good Ones Are Hard to Find",
750 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988),
751 * (2) "Two Fast Implementations of the 'Minimal Standard' Random
752 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88.
753 */
754 const unsigned int a = 16807;
755 const unsigned int m = 2147483647;
756 const int q = m / a; assert(q == 127773, "weird math");
757 const int r = m % a; assert(r == 2836, "weird math");
758
759 // compute az=2^31p+q
760 unsigned int lo = a * (rand_seed & 0xFFFF);
761 unsigned int hi = a * (rand_seed >> 16);
762 lo += (hi & 0x7FFF) << 16;
763
764 // if q overflowed, ignore the overflow and increment q
765 if (lo > m) {
766 lo &= m;
767 ++lo;
768 }
769 lo += hi >> 15;
770
771 // if (p+q) overflowed, ignore the overflow and increment (p+q)
772 if (lo > m) {
773 lo &= m;
774 ++lo;
775 }
776 return lo;
777 }
778
779 int os::random() {
780 // Make updating the random seed thread safe.
781 while (true) {
782 unsigned int seed = _rand_seed;
783 unsigned int rand = next_random(seed);
784 if (Atomic::cmpxchg(&_rand_seed, seed, rand, memory_order_relaxed) == seed) {
785 return static_cast<int>(rand);
786 }
787 }
788 }
789
790 // The INITIALIZED state is distinguished from the SUSPENDED state because the
791 // conditions in which a thread is first started are different from those in which
792 // a suspension is resumed. These differences make it hard for us to apply the
793 // tougher checks when starting threads that we want to do when resuming them.
794 // However, when start_thread is called as a result of Thread.start, on a Java
795 // thread, the operation is synchronized on the Java Thread object. So there
796 // cannot be a race to start the thread and hence for the thread to exit while
797 // we are working on it. Non-Java threads that start Java threads either have
798 // to do so in a context in which races are impossible, or should do appropriate
799 // locking.
800
801 void os::start_thread(Thread* thread) {
802 OSThread* osthread = thread->osthread();
803 osthread->set_state(RUNNABLE);
804 pd_start_thread(thread);
805 }
806
807 void os::abort(bool dump_core) {
808 abort(dump_core && CreateCoredumpOnCrash, NULL, NULL);
809 }
810
811 //---------------------------------------------------------------------------
812 // Helper functions for fatal error handler
813
814 bool os::print_function_and_library_name(outputStream* st,
815 address addr,
816 char* buf, int buflen,
817 bool shorten_paths,
818 bool demangle,
819 bool strip_arguments) {
820 // If no scratch buffer given, allocate one here on stack.
821 // (used during error handling; its a coin toss, really, if on-stack allocation
822 // is worse than (raw) C-heap allocation in that case).
823 char* p = buf;
824 if (p == NULL) {
825 p = (char*)::alloca(O_BUFLEN);
826 buflen = O_BUFLEN;
827 }
828 int offset = 0;
829 bool have_function_name = dll_address_to_function_name(addr, p, buflen,
830 &offset, demangle);
831 bool is_function_descriptor = false;
832 #ifdef HAVE_FUNCTION_DESCRIPTORS
833 // When we deal with a function descriptor instead of a real code pointer, try to
834 // resolve it. There is a small chance that a random pointer given to this function
835 // may just happen to look like a valid descriptor, but this is rare and worth the
836 // risk to see resolved function names. But we will print a little suffix to mark
837 // this as a function descriptor for the reader (see below).
838 if (!have_function_name && os::is_readable_pointer(addr)) {
839 address addr2 = (address)os::resolve_function_descriptor(addr);
840 if (have_function_name = is_function_descriptor =
841 dll_address_to_function_name(addr2, p, buflen, &offset, demangle)) {
842 addr = addr2;
843 }
844 }
845 #endif // HAVE_FUNCTION_DESCRIPTORS
846
847 if (have_function_name) {
848 // Print function name, optionally demangled
849 if (demangle && strip_arguments) {
850 char* args_start = strchr(p, '(');
851 if (args_start != NULL) {
852 *args_start = '\0';
853 }
854 }
855 // Print offset. Omit printing if offset is zero, which makes the output
856 // more readable if we print function pointers.
857 if (offset == 0) {
858 st->print("%s", p);
859 } else {
860 st->print("%s+%d", p, offset);
861 }
862 } else {
863 st->print(PTR_FORMAT, p2i(addr));
864 }
865 offset = 0;
866
867 const bool have_library_name = dll_address_to_library_name(addr, p, buflen, &offset);
868 if (have_library_name) {
869 // Cut path parts
870 if (shorten_paths) {
871 char* p2 = strrchr(p, os::file_separator()[0]);
872 if (p2 != NULL) {
873 p = p2 + 1;
874 }
875 }
876 st->print(" in %s", p);
877 if (!have_function_name) { // Omit offset if we already printed the function offset
878 st->print("+%d", offset);
879 }
880 }
881
882 // Write a trailing marker if this was a function descriptor
883 if (have_function_name && is_function_descriptor) {
884 st->print_raw(" (FD)");
885 }
886
887 return have_function_name || have_library_name;
888 }
889
890 void os::print_hex_dump(outputStream* st, address start, address end, int unitsize,
891 int bytes_per_line, address logical_start) {
892 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking");
893
894 start = align_down(start, unitsize);
895 logical_start = align_down(logical_start, unitsize);
896 bytes_per_line = align_up(bytes_per_line, 8);
897
898 int cols = 0;
899 int cols_per_line = bytes_per_line / unitsize;
900
901 address p = start;
902 address logical_p = logical_start;
903
904 // Print out the addresses as if we were starting from logical_start.
905 st->print(PTR_FORMAT ": ", p2i(logical_p));
906 while (p < end) {
907 if (is_readable_pointer(p)) {
908 switch (unitsize) {
909 case 1: st->print("%02x", *(u1*)p); break;
910 case 2: st->print("%04x", *(u2*)p); break;
911 case 4: st->print("%08x", *(u4*)p); break;
912 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break;
913 }
914 } else {
915 st->print("%*.*s", 2*unitsize, 2*unitsize, "????????????????");
916 }
917 p += unitsize;
918 logical_p += unitsize;
919 cols++;
920 if (cols >= cols_per_line && p < end) {
921 cols = 0;
922 st->cr();
923 st->print(PTR_FORMAT ": ", p2i(logical_p));
924 } else {
925 st->print(" ");
926 }
927 }
928 st->cr();
929 }
930
931 void os::print_dhm(outputStream* st, const char* startStr, long sec) {
932 long days = sec/86400;
933 long hours = (sec/3600) - (days * 24);
934 long minutes = (sec/60) - (days * 1440) - (hours * 60);
935 if (startStr == NULL) startStr = "";
936 st->print_cr("%s %ld days %ld:%02ld hours", startStr, days, hours, minutes);
937 }
938
939 void os::print_tos(outputStream* st, address sp) {
940 st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", p2i(sp));
941 print_hex_dump(st, sp, sp + 512, sizeof(intptr_t));
942 }
943
944 void os::print_instructions(outputStream* st, address pc, int unitsize) {
945 st->print_cr("Instructions: (pc=" PTR_FORMAT ")", p2i(pc));
946 print_hex_dump(st, pc - 256, pc + 256, unitsize);
947 }
948
949 void os::print_environment_variables(outputStream* st, const char** env_list) {
950 if (env_list) {
951 st->print_cr("Environment Variables:");
952
953 for (int i = 0; env_list[i] != NULL; i++) {
954 char *envvar = ::getenv(env_list[i]);
955 if (envvar != NULL) {
956 st->print("%s", env_list[i]);
957 st->print("=");
958 st->print("%s", envvar);
959 // Use separate cr() printing to avoid unnecessary buffer operations that might cause truncation.
960 st->cr();
961 }
962 }
963 }
964 }
965
966 void os::print_cpu_info(outputStream* st, char* buf, size_t buflen) {
967 // cpu
968 st->print("CPU:");
969 #if defined(__APPLE__) && !defined(ZERO)
970 if (VM_Version::is_cpu_emulated()) {
971 st->print(" (EMULATED)");
972 }
973 #endif
974 st->print(" total %d", os::processor_count());
975 // It's not safe to query number of active processors after crash
976 // st->print("(active %d)", os::active_processor_count()); but we can
977 // print the initial number of active processors.
978 // We access the raw value here because the assert in the accessor will
979 // fail if the crash occurs before initialization of this value.
980 st->print(" (initial active %d)", _initial_active_processor_count);
981 st->print(" %s", VM_Version::features_string());
982 st->cr();
983 pd_print_cpu_info(st, buf, buflen);
984 }
985
986 // Print a one line string summarizing the cpu, number of cores, memory, and operating system version
987 void os::print_summary_info(outputStream* st, char* buf, size_t buflen) {
988 st->print("Host: ");
989 #ifndef PRODUCT
990 if (get_host_name(buf, buflen)) {
991 st->print("%s, ", buf);
992 }
993 #endif // PRODUCT
994 get_summary_cpu_info(buf, buflen);
995 st->print("%s, ", buf);
996 size_t mem = physical_memory()/G;
997 if (mem == 0) { // for low memory systems
998 mem = physical_memory()/M;
999 st->print("%d cores, " SIZE_FORMAT "M, ", processor_count(), mem);
1000 } else {
1001 st->print("%d cores, " SIZE_FORMAT "G, ", processor_count(), mem);
1002 }
1003 get_summary_os_info(buf, buflen);
1004 st->print_raw(buf);
1005 st->cr();
1006 }
1007
1008 void os::print_date_and_time(outputStream *st, char* buf, size_t buflen) {
1009 const int secs_per_day = 86400;
1010 const int secs_per_hour = 3600;
1011 const int secs_per_min = 60;
1012
1013 time_t tloc;
1014 (void)time(&tloc);
1015 char* timestring = ctime(&tloc); // ctime adds newline.
1016 // edit out the newline
1017 char* nl = strchr(timestring, '\n');
1018 if (nl != NULL) {
1019 *nl = '\0';
1020 }
1021
1022 struct tm tz;
1023 if (localtime_pd(&tloc, &tz) != NULL) {
1024 wchar_t w_buf[80];
1025 size_t n = ::wcsftime(w_buf, 80, L"%Z", &tz);
1026 if (n > 0) {
1027 ::wcstombs(buf, w_buf, buflen);
1028 st->print("Time: %s %s", timestring, buf);
1029 } else {
1030 st->print("Time: %s", timestring);
1031 }
1032 } else {
1033 st->print("Time: %s", timestring);
1034 }
1035
1036 double t = os::elapsedTime();
1037 // NOTE: a crash using printf("%f",...) on Linux was historically noted here.
1038 int eltime = (int)t; // elapsed time in seconds
1039 int eltimeFraction = (int) ((t - eltime) * 1000000);
1040
1041 // print elapsed time in a human-readable format:
1042 int eldays = eltime / secs_per_day;
1043 int day_secs = eldays * secs_per_day;
1044 int elhours = (eltime - day_secs) / secs_per_hour;
1045 int hour_secs = elhours * secs_per_hour;
1046 int elmins = (eltime - day_secs - hour_secs) / secs_per_min;
1047 int minute_secs = elmins * secs_per_min;
1048 int elsecs = (eltime - day_secs - hour_secs - minute_secs);
1049 st->print_cr(" elapsed time: %d.%06d seconds (%dd %dh %dm %ds)", eltime, eltimeFraction, eldays, elhours, elmins, elsecs);
1050 }
1051
1052
1053 // Check if pointer can be read from (4-byte read access).
1054 // Helps to prove validity of a not-NULL pointer.
1055 // Returns true in very early stages of VM life when stub is not yet generated.
1056 bool os::is_readable_pointer(const void* p) {
1057 int* const aligned = (int*) align_down((intptr_t)p, 4);
1058 int cafebabe = 0xcafebabe; // tester value 1
1059 int deadbeef = 0xdeadbeef; // tester value 2
1060 return (SafeFetch32(aligned, cafebabe) != cafebabe) || (SafeFetch32(aligned, deadbeef) != deadbeef);
1061 }
1062
1063 bool os::is_readable_range(const void* from, const void* to) {
1064 if ((uintptr_t)from >= (uintptr_t)to) return false;
1065 for (uintptr_t p = align_down((uintptr_t)from, min_page_size()); p < (uintptr_t)to; p += min_page_size()) {
1066 if (!is_readable_pointer((const void*)p)) {
1067 return false;
1068 }
1069 }
1070 return true;
1071 }
1072
1073
1074 // moved from debug.cpp (used to be find()) but still called from there
1075 // The verbose parameter is only set by the debug code in one case
1076 void os::print_location(outputStream* st, intptr_t x, bool verbose) {
1077 address addr = (address)x;
1078 // Handle NULL first, so later checks don't need to protect against it.
1079 if (addr == NULL) {
1080 st->print_cr("0x0 is NULL");
1081 return;
1082 }
1083
1084 // Check if addr points into a code blob.
1085 CodeBlob* b = CodeCache::find_blob(addr);
1086 if (b != NULL) {
1087 b->dump_for_addr(addr, st, verbose);
1088 return;
1089 }
1090
1091 // Check if addr points into Java heap.
1092 if (Universe::heap()->print_location(st, addr)) {
1093 return;
1094 }
1095
1096 bool accessible = is_readable_pointer(addr);
1097
1098 // Check if addr is a JNI handle.
1099 if (align_down((intptr_t)addr, sizeof(intptr_t)) != 0 && accessible) {
1100 if (JNIHandles::is_global_handle((jobject) addr)) {
1101 st->print_cr(INTPTR_FORMAT " is a global jni handle", p2i(addr));
1102 return;
1103 }
1104 if (JNIHandles::is_weak_global_handle((jobject) addr)) {
1105 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", p2i(addr));
1106 return;
1107 }
1108 }
1109
1110 // Check if addr belongs to a Java thread.
1111 for (JavaThreadIteratorWithHandle jtiwh; JavaThread *thread = jtiwh.next(); ) {
1112 // If the addr is a java thread print information about that.
1113 if (addr == (address)thread) {
1114 if (verbose) {
1115 thread->print_on(st);
1116 } else {
1117 st->print_cr(INTPTR_FORMAT " is a thread", p2i(addr));
1118 }
1119 return;
1120 }
1121 // If the addr is in the stack region for this thread then report that
1122 // and print thread info
1123 if (thread->is_in_full_stack(addr)) {
1124 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: "
1125 INTPTR_FORMAT, p2i(addr), p2i(thread));
1126 if (verbose) thread->print_on(st);
1127 return;
1128 }
1129 }
1130
1131 // Check if in metaspace and print types that have vptrs
1132 if (Metaspace::contains(addr)) {
1133 if (Klass::is_valid((Klass*)addr)) {
1134 st->print_cr(INTPTR_FORMAT " is a pointer to class: ", p2i(addr));
1135 ((Klass*)addr)->print_on(st);
1136 } else if (Method::is_valid_method((const Method*)addr)) {
1137 ((Method*)addr)->print_value_on(st);
1138 st->cr();
1139 } else {
1140 // Use addr->print() from the debugger instead (not here)
1141 st->print_cr(INTPTR_FORMAT " is pointing into metadata", p2i(addr));
1142 }
1143 return;
1144 }
1145
1146 // Compressed klass needs to be decoded first.
1147 #ifdef _LP64
1148 if (UseCompressedClassPointers && ((uintptr_t)addr &~ (uintptr_t)max_juint) == 0) {
1149 narrowKlass narrow_klass = (narrowKlass)(uintptr_t)addr;
1150 Klass* k = CompressedKlassPointers::decode_raw(narrow_klass);
1151
1152 if (Klass::is_valid(k)) {
1153 st->print_cr(UINT32_FORMAT " is a compressed pointer to class: " INTPTR_FORMAT, narrow_klass, p2i((HeapWord*)k));
1154 k->print_on(st);
1155 return;
1156 }
1157 }
1158 #endif
1159
1160 // Try an OS specific find
1161 if (os::find(addr, st)) {
1162 return;
1163 }
1164
1165 if (accessible) {
1166 st->print(INTPTR_FORMAT " points into unknown readable memory:", p2i(addr));
1167 if (is_aligned(addr, sizeof(intptr_t))) {
1168 st->print(" " PTR_FORMAT " |", *(intptr_t*)addr);
1169 }
1170 for (address p = addr; p < align_up(addr + 1, sizeof(intptr_t)); ++p) {
1171 st->print(" %02x", *(u1*)p);
1172 }
1173 st->cr();
1174 return;
1175 }
1176
1177 st->print_cr(INTPTR_FORMAT " is an unknown value", p2i(addr));
1178 }
1179
1180 bool is_pointer_bad(intptr_t* ptr) {
1181 return !is_aligned(ptr, sizeof(uintptr_t)) || !os::is_readable_pointer(ptr);
1182 }
1183
1184 // Looks like all platforms can use the same function to check if C
1185 // stack is walkable beyond current frame.
1186 // Returns true if this is not the case, i.e. the frame is possibly
1187 // the first C frame on the stack.
1188 bool os::is_first_C_frame(frame* fr) {
1189
1190 #ifdef _WINDOWS
1191 return true; // native stack isn't walkable on windows this way.
1192 #endif
1193 // Load up sp, fp, sender sp and sender fp, check for reasonable values.
1194 // Check usp first, because if that's bad the other accessors may fault
1195 // on some architectures. Ditto ufp second, etc.
1196
1197 if (is_pointer_bad(fr->sp())) return true;
1198
1199 uintptr_t ufp = (uintptr_t)fr->fp();
1200 if (is_pointer_bad(fr->fp())) return true;
1201
1202 uintptr_t old_sp = (uintptr_t)fr->sender_sp();
1203 if ((uintptr_t)fr->sender_sp() == (uintptr_t)-1 || is_pointer_bad(fr->sender_sp())) return true;
1204
1205 uintptr_t old_fp = (uintptr_t)fr->link_or_null();
1206 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp ||
1207 is_pointer_bad(fr->link_or_null())) return true;
1208
1209 // stack grows downwards; if old_fp is below current fp or if the stack
1210 // frame is too large, either the stack is corrupted or fp is not saved
1211 // on stack (i.e. on x86, ebp may be used as general register). The stack
1212 // is not walkable beyond current frame.
1213 if (old_fp < ufp) return true;
1214 if (old_fp - ufp > 64 * K) return true;
1215
1216 return false;
1217 }
1218
1219 // Set up the boot classpath.
1220
1221 char* os::format_boot_path(const char* format_string,
1222 const char* home,
1223 int home_len,
1224 char fileSep,
1225 char pathSep) {
1226 assert((fileSep == '/' && pathSep == ':') ||
1227 (fileSep == '\\' && pathSep == ';'), "unexpected separator chars");
1228
1229 // Scan the format string to determine the length of the actual
1230 // boot classpath, and handle platform dependencies as well.
1231 int formatted_path_len = 0;
1232 const char* p;
1233 for (p = format_string; *p != 0; ++p) {
1234 if (*p == '%') formatted_path_len += home_len - 1;
1235 ++formatted_path_len;
1236 }
1237
1238 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal);
1239
1240 // Create boot classpath from format, substituting separator chars and
1241 // java home directory.
1242 char* q = formatted_path;
1243 for (p = format_string; *p != 0; ++p) {
1244 switch (*p) {
1245 case '%':
1246 strcpy(q, home);
1247 q += home_len;
1248 break;
1249 case '/':
1250 *q++ = fileSep;
1251 break;
1252 case ':':
1253 *q++ = pathSep;
1254 break;
1255 default:
1256 *q++ = *p;
1257 }
1258 }
1259 *q = '\0';
1260
1261 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched");
1262 return formatted_path;
1263 }
1264
1265 // This function is a proxy to fopen, it tries to add a non standard flag ('e' or 'N')
1266 // that ensures automatic closing of the file on exec. If it can not find support in
1267 // the underlying c library, it will make an extra system call (fcntl) to ensure automatic
1268 // closing of the file on exec.
1269 FILE* os::fopen(const char* path, const char* mode) {
1270 char modified_mode[20];
1271 assert(strlen(mode) + 1 < sizeof(modified_mode), "mode chars plus one extra must fit in buffer");
1272 sprintf(modified_mode, "%s" LINUX_ONLY("e") BSD_ONLY("e") WINDOWS_ONLY("N"), mode);
1273 FILE* file = ::fopen(path, modified_mode);
1274
1275 #if !(defined LINUX || defined BSD || defined _WINDOWS)
1276 // assume fcntl FD_CLOEXEC support as a backup solution when 'e' or 'N'
1277 // is not supported as mode in fopen
1278 if (file != NULL) {
1279 int fd = fileno(file);
1280 if (fd != -1) {
1281 int fd_flags = fcntl(fd, F_GETFD);
1282 if (fd_flags != -1) {
1283 fcntl(fd, F_SETFD, fd_flags | FD_CLOEXEC);
1284 }
1285 }
1286 }
1287 #endif
1288
1289 return file;
1290 }
1291
1292 bool os::set_boot_path(char fileSep, char pathSep) {
1293 const char* home = Arguments::get_java_home();
1294 int home_len = (int)strlen(home);
1295
1296 struct stat st;
1297
1298 // modular image if "modules" jimage exists
1299 char* jimage = format_boot_path("%/lib/" MODULES_IMAGE_NAME, home, home_len, fileSep, pathSep);
1300 if (jimage == NULL) return false;
1301 bool has_jimage = (os::stat(jimage, &st) == 0);
1302 if (has_jimage) {
1303 Arguments::set_boot_class_path(jimage, true);
1304 FREE_C_HEAP_ARRAY(char, jimage);
1305 return true;
1306 }
1307 FREE_C_HEAP_ARRAY(char, jimage);
1308
1309 // check if developer build with exploded modules
1310 char* base_classes = format_boot_path("%/modules/" JAVA_BASE_NAME, home, home_len, fileSep, pathSep);
1311 if (base_classes == NULL) return false;
1312 if (os::stat(base_classes, &st) == 0) {
1313 Arguments::set_boot_class_path(base_classes, false);
1314 FREE_C_HEAP_ARRAY(char, base_classes);
1315 return true;
1316 }
1317 FREE_C_HEAP_ARRAY(char, base_classes);
1318
1319 return false;
1320 }
1321
1322 bool os::file_exists(const char* filename) {
1323 struct stat statbuf;
1324 if (filename == NULL || strlen(filename) == 0) {
1325 return false;
1326 }
1327 return os::stat(filename, &statbuf) == 0;
1328 }
1329
1330 // Splits a path, based on its separator, the number of
1331 // elements is returned back in "elements".
1332 // file_name_length is used as a modifier for each path's
1333 // length when compared to JVM_MAXPATHLEN. So if you know
1334 // each returned path will have something appended when
1335 // in use, you can pass the length of that in
1336 // file_name_length, to ensure we detect if any path
1337 // exceeds the maximum path length once prepended onto
1338 // the sub-path/file name.
1339 // It is the callers responsibility to:
1340 // a> check the value of "elements", which may be 0.
1341 // b> ignore any empty path elements
1342 // c> free up the data.
1343 char** os::split_path(const char* path, size_t* elements, size_t file_name_length) {
1344 *elements = (size_t)0;
1345 if (path == NULL || strlen(path) == 0 || file_name_length == (size_t)NULL) {
1346 return NULL;
1347 }
1348 const char psepchar = *os::path_separator();
1349 char* inpath = NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal);
1350 strcpy(inpath, path);
1351 size_t count = 1;
1352 char* p = strchr(inpath, psepchar);
1353 // Get a count of elements to allocate memory
1354 while (p != NULL) {
1355 count++;
1356 p++;
1357 p = strchr(p, psepchar);
1358 }
1359
1360 char** opath = NEW_C_HEAP_ARRAY(char*, count, mtInternal);
1361
1362 // do the actual splitting
1363 p = inpath;
1364 for (size_t i = 0 ; i < count ; i++) {
1365 size_t len = strcspn(p, os::path_separator());
1366 if (len + file_name_length > JVM_MAXPATHLEN) {
1367 // release allocated storage before exiting the vm
1368 free_array_of_char_arrays(opath, i++);
1369 vm_exit_during_initialization("The VM tried to use a path that exceeds the maximum path length for "
1370 "this system. Review path-containing parameters and properties, such as "
1371 "sun.boot.library.path, to identify potential sources for this path.");
1372 }
1373 // allocate the string and add terminator storage
1374 char* s = NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
1375 strncpy(s, p, len);
1376 s[len] = '\0';
1377 opath[i] = s;
1378 p += len + 1;
1379 }
1380 FREE_C_HEAP_ARRAY(char, inpath);
1381 *elements = count;
1382 return opath;
1383 }
1384
1385 // Returns true if the current stack pointer is above the stack shadow
1386 // pages, false otherwise.
1387 bool os::stack_shadow_pages_available(Thread *thread, const methodHandle& method, address sp) {
1388 if (!thread->is_Java_thread()) return false;
1389 // Check if we have StackShadowPages above the guard zone. This parameter
1390 // is dependent on the depth of the maximum VM call stack possible from
1391 // the handler for stack overflow. 'instanceof' in the stack overflow
1392 // handler or a println uses at least 8k stack of VM and native code
1393 // respectively.
1394 const int framesize_in_bytes =
1395 Interpreter::size_top_interpreter_activation(method()) * wordSize;
1396
1397 address limit = JavaThread::cast(thread)->stack_overflow_state()->shadow_zone_safe_limit();
1398 return sp > (limit + framesize_in_bytes);
1399 }
1400
1401 size_t os::page_size_for_region(size_t region_size, size_t min_pages, bool must_be_aligned) {
1402 assert(min_pages > 0, "sanity");
1403 if (UseLargePages) {
1404 const size_t max_page_size = region_size / min_pages;
1405
1406 for (size_t page_size = page_sizes().largest(); page_size != 0;
1407 page_size = page_sizes().next_smaller(page_size)) {
1408 if (page_size <= max_page_size) {
1409 if (!must_be_aligned || is_aligned(region_size, page_size)) {
1410 return page_size;
1411 }
1412 }
1413 }
1414 }
1415
1416 return vm_page_size();
1417 }
1418
1419 size_t os::page_size_for_region_aligned(size_t region_size, size_t min_pages) {
1420 return page_size_for_region(region_size, min_pages, true);
1421 }
1422
1423 size_t os::page_size_for_region_unaligned(size_t region_size, size_t min_pages) {
1424 return page_size_for_region(region_size, min_pages, false);
1425 }
1426
1427 #ifndef MAX_PATH
1428 #define MAX_PATH (2 * K)
1429 #endif
1430
1431 void os::pause() {
1432 char filename[MAX_PATH];
1433 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
1434 jio_snprintf(filename, MAX_PATH, "%s", PauseAtStartupFile);
1435 } else {
1436 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
1437 }
1438
1439 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
1440 if (fd != -1) {
1441 struct stat buf;
1442 ::close(fd);
1443 while (::stat(filename, &buf) == 0) {
1444 #if defined(_WINDOWS)
1445 Sleep(100);
1446 #else
1447 (void)::poll(NULL, 0, 100);
1448 #endif
1449 }
1450 } else {
1451 jio_fprintf(stderr,
1452 "Could not open pause file '%s', continuing immediately.\n", filename);
1453 }
1454 }
1455
1456 static const char* errno_to_string (int e, bool short_text) {
1457 #define ALL_SHARED_ENUMS(X) \
1458 X(E2BIG, "Argument list too long") \
1459 X(EACCES, "Permission denied") \
1460 X(EADDRINUSE, "Address in use") \
1461 X(EADDRNOTAVAIL, "Address not available") \
1462 X(EAFNOSUPPORT, "Address family not supported") \
1463 X(EAGAIN, "Resource unavailable, try again") \
1464 X(EALREADY, "Connection already in progress") \
1465 X(EBADF, "Bad file descriptor") \
1466 X(EBADMSG, "Bad message") \
1467 X(EBUSY, "Device or resource busy") \
1468 X(ECANCELED, "Operation canceled") \
1469 X(ECHILD, "No child processes") \
1470 X(ECONNABORTED, "Connection aborted") \
1471 X(ECONNREFUSED, "Connection refused") \
1472 X(ECONNRESET, "Connection reset") \
1473 X(EDEADLK, "Resource deadlock would occur") \
1474 X(EDESTADDRREQ, "Destination address required") \
1475 X(EDOM, "Mathematics argument out of domain of function") \
1476 X(EEXIST, "File exists") \
1477 X(EFAULT, "Bad address") \
1478 X(EFBIG, "File too large") \
1479 X(EHOSTUNREACH, "Host is unreachable") \
1480 X(EIDRM, "Identifier removed") \
1481 X(EILSEQ, "Illegal byte sequence") \
1482 X(EINPROGRESS, "Operation in progress") \
1483 X(EINTR, "Interrupted function") \
1484 X(EINVAL, "Invalid argument") \
1485 X(EIO, "I/O error") \
1486 X(EISCONN, "Socket is connected") \
1487 X(EISDIR, "Is a directory") \
1488 X(ELOOP, "Too many levels of symbolic links") \
1489 X(EMFILE, "Too many open files") \
1490 X(EMLINK, "Too many links") \
1491 X(EMSGSIZE, "Message too large") \
1492 X(ENAMETOOLONG, "Filename too long") \
1493 X(ENETDOWN, "Network is down") \
1494 X(ENETRESET, "Connection aborted by network") \
1495 X(ENETUNREACH, "Network unreachable") \
1496 X(ENFILE, "Too many files open in system") \
1497 X(ENOBUFS, "No buffer space available") \
1498 X(ENODATA, "No message is available on the STREAM head read queue") \
1499 X(ENODEV, "No such device") \
1500 X(ENOENT, "No such file or directory") \
1501 X(ENOEXEC, "Executable file format error") \
1502 X(ENOLCK, "No locks available") \
1503 X(ENOLINK, "Reserved") \
1504 X(ENOMEM, "Not enough space") \
1505 X(ENOMSG, "No message of the desired type") \
1506 X(ENOPROTOOPT, "Protocol not available") \
1507 X(ENOSPC, "No space left on device") \
1508 X(ENOSR, "No STREAM resources") \
1509 X(ENOSTR, "Not a STREAM") \
1510 X(ENOSYS, "Function not supported") \
1511 X(ENOTCONN, "The socket is not connected") \
1512 X(ENOTDIR, "Not a directory") \
1513 X(ENOTEMPTY, "Directory not empty") \
1514 X(ENOTSOCK, "Not a socket") \
1515 X(ENOTSUP, "Not supported") \
1516 X(ENOTTY, "Inappropriate I/O control operation") \
1517 X(ENXIO, "No such device or address") \
1518 X(EOPNOTSUPP, "Operation not supported on socket") \
1519 X(EOVERFLOW, "Value too large to be stored in data type") \
1520 X(EPERM, "Operation not permitted") \
1521 X(EPIPE, "Broken pipe") \
1522 X(EPROTO, "Protocol error") \
1523 X(EPROTONOSUPPORT, "Protocol not supported") \
1524 X(EPROTOTYPE, "Protocol wrong type for socket") \
1525 X(ERANGE, "Result too large") \
1526 X(EROFS, "Read-only file system") \
1527 X(ESPIPE, "Invalid seek") \
1528 X(ESRCH, "No such process") \
1529 X(ETIME, "Stream ioctl() timeout") \
1530 X(ETIMEDOUT, "Connection timed out") \
1531 X(ETXTBSY, "Text file busy") \
1532 X(EWOULDBLOCK, "Operation would block") \
1533 X(EXDEV, "Cross-device link")
1534
1535 #define DEFINE_ENTRY(e, text) { e, #e, text },
1536
1537 static const struct {
1538 int v;
1539 const char* short_text;
1540 const char* long_text;
1541 } table [] = {
1542
1543 ALL_SHARED_ENUMS(DEFINE_ENTRY)
1544
1545 // The following enums are not defined on all platforms.
1546 #ifdef ESTALE
1547 DEFINE_ENTRY(ESTALE, "Reserved")
1548 #endif
1549 #ifdef EDQUOT
1550 DEFINE_ENTRY(EDQUOT, "Reserved")
1551 #endif
1552 #ifdef EMULTIHOP
1553 DEFINE_ENTRY(EMULTIHOP, "Reserved")
1554 #endif
1555
1556 // End marker.
1557 { -1, "Unknown errno", "Unknown error" }
1558
1559 };
1560
1561 #undef DEFINE_ENTRY
1562 #undef ALL_FLAGS
1563
1564 int i = 0;
1565 while (table[i].v != -1 && table[i].v != e) {
1566 i ++;
1567 }
1568
1569 return short_text ? table[i].short_text : table[i].long_text;
1570
1571 }
1572
1573 const char* os::strerror(int e) {
1574 return errno_to_string(e, false);
1575 }
1576
1577 const char* os::errno_name(int e) {
1578 return errno_to_string(e, true);
1579 }
1580
1581 #define trace_page_size_params(size) byte_size_in_exact_unit(size), exact_unit_for_byte_size(size)
1582
1583 void os::trace_page_sizes(const char* str,
1584 const size_t region_min_size,
1585 const size_t region_max_size,
1586 const size_t page_size,
1587 const char* base,
1588 const size_t size) {
1589
1590 log_info(pagesize)("%s: "
1591 " min=" SIZE_FORMAT "%s"
1592 " max=" SIZE_FORMAT "%s"
1593 " base=" PTR_FORMAT
1594 " page_size=" SIZE_FORMAT "%s"
1595 " size=" SIZE_FORMAT "%s",
1596 str,
1597 trace_page_size_params(region_min_size),
1598 trace_page_size_params(region_max_size),
1599 p2i(base),
1600 trace_page_size_params(page_size),
1601 trace_page_size_params(size));
1602 }
1603
1604 void os::trace_page_sizes_for_requested_size(const char* str,
1605 const size_t requested_size,
1606 const size_t page_size,
1607 const size_t alignment,
1608 const char* base,
1609 const size_t size) {
1610
1611 log_info(pagesize)("%s:"
1612 " req_size=" SIZE_FORMAT "%s"
1613 " base=" PTR_FORMAT
1614 " page_size=" SIZE_FORMAT "%s"
1615 " alignment=" SIZE_FORMAT "%s"
1616 " size=" SIZE_FORMAT "%s",
1617 str,
1618 trace_page_size_params(requested_size),
1619 p2i(base),
1620 trace_page_size_params(page_size),
1621 trace_page_size_params(alignment),
1622 trace_page_size_params(size));
1623 }
1624
1625
1626 // This is the working definition of a server class machine:
1627 // >= 2 physical CPU's and >=2GB of memory, with some fuzz
1628 // because the graphics memory (?) sometimes masks physical memory.
1629 // If you want to change the definition of a server class machine
1630 // on some OS or platform, e.g., >=4GB on Windows platforms,
1631 // then you'll have to parameterize this method based on that state,
1632 // as was done for logical processors here, or replicate and
1633 // specialize this method for each platform. (Or fix os to have
1634 // some inheritance structure and use subclassing. Sigh.)
1635 // If you want some platform to always or never behave as a server
1636 // class machine, change the setting of AlwaysActAsServerClassMachine
1637 // and NeverActAsServerClassMachine in globals*.hpp.
1638 bool os::is_server_class_machine() {
1639 // First check for the early returns
1640 if (NeverActAsServerClassMachine) {
1641 return false;
1642 }
1643 if (AlwaysActAsServerClassMachine) {
1644 return true;
1645 }
1646 // Then actually look at the machine
1647 bool result = false;
1648 const unsigned int server_processors = 2;
1649 const julong server_memory = 2UL * G;
1650 // We seem not to get our full complement of memory.
1651 // We allow some part (1/8?) of the memory to be "missing",
1652 // based on the sizes of DIMMs, and maybe graphics cards.
1653 const julong missing_memory = 256UL * M;
1654
1655 /* Is this a server class machine? */
1656 if ((os::active_processor_count() >= (int)server_processors) &&
1657 (os::physical_memory() >= (server_memory - missing_memory))) {
1658 const unsigned int logical_processors =
1659 VM_Version::logical_processors_per_package();
1660 if (logical_processors > 1) {
1661 const unsigned int physical_packages =
1662 os::active_processor_count() / logical_processors;
1663 if (physical_packages >= server_processors) {
1664 result = true;
1665 }
1666 } else {
1667 result = true;
1668 }
1669 }
1670 return result;
1671 }
1672
1673 void os::initialize_initial_active_processor_count() {
1674 assert(_initial_active_processor_count == 0, "Initial active processor count already set.");
1675 _initial_active_processor_count = active_processor_count();
1676 log_debug(os)("Initial active processor count set to %d" , _initial_active_processor_count);
1677 }
1678
1679 bool os::create_stack_guard_pages(char* addr, size_t bytes) {
1680 return os::pd_create_stack_guard_pages(addr, bytes);
1681 }
1682
1683 char* os::reserve_memory(size_t bytes, bool executable, MEMFLAGS flags) {
1684 char* result = pd_reserve_memory(bytes, executable);
1685 if (result != NULL) {
1686 MemTracker::record_virtual_memory_reserve(result, bytes, CALLER_PC, flags);
1687 }
1688 return result;
1689 }
1690
1691 char* os::attempt_reserve_memory_at(char* addr, size_t bytes, bool executable) {
1692 char* result = pd_attempt_reserve_memory_at(addr, bytes, executable);
1693 if (result != NULL) {
1694 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1695 } else {
1696 log_debug(os)("Attempt to reserve memory at " INTPTR_FORMAT " for "
1697 SIZE_FORMAT " bytes failed, errno %d", p2i(addr), bytes, get_last_error());
1698 }
1699 return result;
1700 }
1701
1702 static void assert_nonempty_range(const char* addr, size_t bytes) {
1703 assert(addr != nullptr && bytes > 0, "invalid range [" PTR_FORMAT ", " PTR_FORMAT ")",
1704 p2i(addr), p2i(addr) + bytes);
1705 }
1706
1707 bool os::commit_memory(char* addr, size_t bytes, bool executable) {
1708 assert_nonempty_range(addr, bytes);
1709 bool res = pd_commit_memory(addr, bytes, executable);
1710 if (res) {
1711 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1712 }
1713 return res;
1714 }
1715
1716 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint,
1717 bool executable) {
1718 assert_nonempty_range(addr, size);
1719 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable);
1720 if (res) {
1721 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1722 }
1723 return res;
1724 }
1725
1726 void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable,
1727 const char* mesg) {
1728 assert_nonempty_range(addr, bytes);
1729 pd_commit_memory_or_exit(addr, bytes, executable, mesg);
1730 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1731 }
1732
1733 void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint,
1734 bool executable, const char* mesg) {
1735 assert_nonempty_range(addr, size);
1736 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg);
1737 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1738 }
1739
1740 bool os::uncommit_memory(char* addr, size_t bytes, bool executable) {
1741 assert_nonempty_range(addr, bytes);
1742 bool res;
1743 if (MemTracker::enabled()) {
1744 Tracker tkr(Tracker::uncommit);
1745 res = pd_uncommit_memory(addr, bytes, executable);
1746 if (res) {
1747 tkr.record((address)addr, bytes);
1748 }
1749 } else {
1750 res = pd_uncommit_memory(addr, bytes, executable);
1751 }
1752 return res;
1753 }
1754
1755 bool os::release_memory(char* addr, size_t bytes) {
1756 assert_nonempty_range(addr, bytes);
1757 bool res;
1758 if (MemTracker::enabled()) {
1759 // Note: Tracker contains a ThreadCritical.
1760 Tracker tkr(Tracker::release);
1761 res = pd_release_memory(addr, bytes);
1762 if (res) {
1763 tkr.record((address)addr, bytes);
1764 }
1765 } else {
1766 res = pd_release_memory(addr, bytes);
1767 }
1768 if (!res) {
1769 log_info(os)("os::release_memory failed (" PTR_FORMAT ", " SIZE_FORMAT ")", p2i(addr), bytes);
1770 }
1771 return res;
1772 }
1773
1774 // Prints all mappings
1775 void os::print_memory_mappings(outputStream* st) {
1776 os::print_memory_mappings(nullptr, (size_t)-1, st);
1777 }
1778
1779 // Pretouching must use a store, not just a load. On many OSes loads from
1780 // fresh memory would be satisfied from a single mapped page containing all
1781 // zeros. We need to store something to each page to get them backed by
1782 // their own memory, which is the effect we want here. An atomic add of
1783 // zero is used instead of a simple store, allowing the memory to be used
1784 // while pretouch is in progress, rather than requiring users of the memory
1785 // to wait until the entire range has been touched. This is technically
1786 // a UB data race, but doesn't cause any problems for us.
1787 void os::pretouch_memory(void* start, void* end, size_t page_size) {
1788 assert(start <= end, "invalid range: " PTR_FORMAT " -> " PTR_FORMAT, p2i(start), p2i(end));
1789 assert(is_power_of_2(page_size), "page size misaligned: %zu", page_size);
1790 assert(page_size >= sizeof(int), "page size too small: %zu", page_size);
1791 if (start < end) {
1792 // We're doing concurrent-safe touch and memory state has page
1793 // granularity, so we can touch anywhere in a page. Touch at the
1794 // beginning of each page to simplify iteration.
1795 char* cur = static_cast<char*>(align_down(start, page_size));
1796 void* last = align_down(static_cast<char*>(end) - 1, page_size);
1797 assert(cur <= last, "invariant");
1798 // Iterate from first page through last (inclusive), being careful to
1799 // avoid overflow if the last page abuts the end of the address range.
1800 for ( ; true; cur += page_size) {
1801 Atomic::add(reinterpret_cast<int*>(cur), 0, memory_order_relaxed);
1802 if (cur >= last) break;
1803 }
1804 }
1805 }
1806
1807 char* os::map_memory_to_file(size_t bytes, int file_desc) {
1808 // Could have called pd_reserve_memory() followed by replace_existing_mapping_with_file_mapping(),
1809 // but AIX may use SHM in which case its more trouble to detach the segment and remap memory to the file.
1810 // On all current implementations NULL is interpreted as any available address.
1811 char* result = os::map_memory_to_file(NULL /* addr */, bytes, file_desc);
1812 if (result != NULL) {
1813 MemTracker::record_virtual_memory_reserve_and_commit(result, bytes, CALLER_PC);
1814 }
1815 return result;
1816 }
1817
1818 char* os::attempt_map_memory_to_file_at(char* addr, size_t bytes, int file_desc) {
1819 char* result = pd_attempt_map_memory_to_file_at(addr, bytes, file_desc);
1820 if (result != NULL) {
1821 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC);
1822 }
1823 return result;
1824 }
1825
1826 char* os::map_memory(int fd, const char* file_name, size_t file_offset,
1827 char *addr, size_t bytes, bool read_only,
1828 bool allow_exec, MEMFLAGS flags) {
1829 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec);
1830 if (result != NULL) {
1831 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC, flags);
1832 }
1833 return result;
1834 }
1835
1836 char* os::remap_memory(int fd, const char* file_name, size_t file_offset,
1837 char *addr, size_t bytes, bool read_only,
1838 bool allow_exec) {
1839 return pd_remap_memory(fd, file_name, file_offset, addr, bytes,
1840 read_only, allow_exec);
1841 }
1842
1843 bool os::unmap_memory(char *addr, size_t bytes) {
1844 bool result;
1845 if (MemTracker::enabled()) {
1846 Tracker tkr(Tracker::release);
1847 result = pd_unmap_memory(addr, bytes);
1848 if (result) {
1849 tkr.record((address)addr, bytes);
1850 }
1851 } else {
1852 result = pd_unmap_memory(addr, bytes);
1853 }
1854 return result;
1855 }
1856
1857 void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) {
1858 pd_free_memory(addr, bytes, alignment_hint);
1859 }
1860
1861 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
1862 pd_realign_memory(addr, bytes, alignment_hint);
1863 }
1864
1865 char* os::reserve_memory_special(size_t size, size_t alignment, size_t page_size,
1866 char* addr, bool executable) {
1867
1868 assert(is_aligned(addr, alignment), "Unaligned request address");
1869
1870 char* result = pd_reserve_memory_special(size, alignment, page_size, addr, executable);
1871 if (result != NULL) {
1872 // The memory is committed
1873 MemTracker::record_virtual_memory_reserve_and_commit((address)result, size, CALLER_PC);
1874 }
1875
1876 return result;
1877 }
1878
1879 bool os::release_memory_special(char* addr, size_t bytes) {
1880 bool res;
1881 if (MemTracker::enabled()) {
1882 // Note: Tracker contains a ThreadCritical.
1883 Tracker tkr(Tracker::release);
1884 res = pd_release_memory_special(addr, bytes);
1885 if (res) {
1886 tkr.record((address)addr, bytes);
1887 }
1888 } else {
1889 res = pd_release_memory_special(addr, bytes);
1890 }
1891 return res;
1892 }
1893
1894 // Convenience wrapper around naked_short_sleep to allow for longer sleep
1895 // times. Only for use by non-JavaThreads.
1896 void os::naked_sleep(jlong millis) {
1897 assert(!Thread::current()->is_Java_thread(), "not for use by JavaThreads");
1898 const jlong limit = 999;
1899 while (millis > limit) {
1900 naked_short_sleep(limit);
1901 millis -= limit;
1902 }
1903 naked_short_sleep(millis);
1904 }
1905
1906
1907 ////// Implementation of PageSizes
1908
1909 void os::PageSizes::add(size_t page_size) {
1910 assert(is_power_of_2(page_size), "page_size must be a power of 2: " SIZE_FORMAT_X, page_size);
1911 _v |= page_size;
1912 }
1913
1914 bool os::PageSizes::contains(size_t page_size) const {
1915 assert(is_power_of_2(page_size), "page_size must be a power of 2: " SIZE_FORMAT_X, page_size);
1916 return (_v & page_size) != 0;
1917 }
1918
1919 size_t os::PageSizes::next_smaller(size_t page_size) const {
1920 assert(is_power_of_2(page_size), "page_size must be a power of 2: " SIZE_FORMAT_X, page_size);
1921 size_t v2 = _v & (page_size - 1);
1922 if (v2 == 0) {
1923 return 0;
1924 }
1925 return round_down_power_of_2(v2);
1926 }
1927
1928 size_t os::PageSizes::next_larger(size_t page_size) const {
1929 assert(is_power_of_2(page_size), "page_size must be a power of 2: " SIZE_FORMAT_X, page_size);
1930 if (page_size == max_power_of_2<size_t>()) { // Shift by 32/64 would be UB
1931 return 0;
1932 }
1933 // Remove current and smaller page sizes
1934 size_t v2 = _v & ~(page_size + (page_size - 1));
1935 if (v2 == 0) {
1936 return 0;
1937 }
1938 return (size_t)1 << count_trailing_zeros(v2);
1939 }
1940
1941 size_t os::PageSizes::largest() const {
1942 const size_t max = max_power_of_2<size_t>();
1943 if (contains(max)) {
1944 return max;
1945 }
1946 return next_smaller(max);
1947 }
1948
1949 size_t os::PageSizes::smallest() const {
1950 // Strictly speaking the set should not contain sizes < os::vm_page_size().
1951 // But this is not enforced.
1952 return next_larger(1);
1953 }
1954
1955 void os::PageSizes::print_on(outputStream* st) const {
1956 bool first = true;
1957 for (size_t sz = smallest(); sz != 0; sz = next_larger(sz)) {
1958 if (first) {
1959 first = false;
1960 } else {
1961 st->print_raw(", ");
1962 }
1963 if (sz < M) {
1964 st->print(SIZE_FORMAT "k", sz / K);
1965 } else if (sz < G) {
1966 st->print(SIZE_FORMAT "M", sz / M);
1967 } else {
1968 st->print(SIZE_FORMAT "G", sz / G);
1969 }
1970 }
1971 if (first) {
1972 st->print("empty");
1973 }
1974 }
1975
1976 // Check minimum allowable stack sizes for thread creation and to initialize
1977 // the java system classes, including StackOverflowError - depends on page
1978 // size.
1979 // The space needed for frames during startup is platform dependent. It
1980 // depends on word size, platform calling conventions, C frame layout and
1981 // interpreter/C1/C2 design decisions. Therefore this is given in a
1982 // platform (os/cpu) dependent constant.
1983 // To this, space for guard mechanisms is added, which depends on the
1984 // page size which again depends on the concrete system the VM is running
1985 // on. Space for libc guard pages is not included in this size.
1986 jint os::set_minimum_stack_sizes() {
1987
1988 _java_thread_min_stack_allowed = _java_thread_min_stack_allowed +
1989 StackOverflow::stack_guard_zone_size() +
1990 StackOverflow::stack_shadow_zone_size();
1991
1992 _java_thread_min_stack_allowed = align_up(_java_thread_min_stack_allowed, vm_page_size());
1993 _java_thread_min_stack_allowed = MAX2(_java_thread_min_stack_allowed, _os_min_stack_allowed);
1994
1995 size_t stack_size_in_bytes = ThreadStackSize * K;
1996 if (stack_size_in_bytes != 0 &&
1997 stack_size_in_bytes < _java_thread_min_stack_allowed) {
1998 // The '-Xss' and '-XX:ThreadStackSize=N' options both set
1999 // ThreadStackSize so we go with "Java thread stack size" instead
2000 // of "ThreadStackSize" to be more friendly.
2001 tty->print_cr("\nThe Java thread stack size specified is too small. "
2002 "Specify at least " SIZE_FORMAT "k",
2003 _java_thread_min_stack_allowed / K);
2004 return JNI_ERR;
2005 }
2006
2007 // Make the stack size a multiple of the page size so that
2008 // the yellow/red zones can be guarded.
2009 JavaThread::set_stack_size_at_create(align_up(stack_size_in_bytes, vm_page_size()));
2010
2011 // Reminder: a compiler thread is a Java thread.
2012 _compiler_thread_min_stack_allowed = _compiler_thread_min_stack_allowed +
2013 StackOverflow::stack_guard_zone_size() +
2014 StackOverflow::stack_shadow_zone_size();
2015
2016 _compiler_thread_min_stack_allowed = align_up(_compiler_thread_min_stack_allowed, vm_page_size());
2017 _compiler_thread_min_stack_allowed = MAX2(_compiler_thread_min_stack_allowed, _os_min_stack_allowed);
2018
2019 stack_size_in_bytes = CompilerThreadStackSize * K;
2020 if (stack_size_in_bytes != 0 &&
2021 stack_size_in_bytes < _compiler_thread_min_stack_allowed) {
2022 tty->print_cr("\nThe CompilerThreadStackSize specified is too small. "
2023 "Specify at least " SIZE_FORMAT "k",
2024 _compiler_thread_min_stack_allowed / K);
2025 return JNI_ERR;
2026 }
2027
2028 _vm_internal_thread_min_stack_allowed = align_up(_vm_internal_thread_min_stack_allowed, vm_page_size());
2029 _vm_internal_thread_min_stack_allowed = MAX2(_vm_internal_thread_min_stack_allowed, _os_min_stack_allowed);
2030
2031 stack_size_in_bytes = VMThreadStackSize * K;
2032 if (stack_size_in_bytes != 0 &&
2033 stack_size_in_bytes < _vm_internal_thread_min_stack_allowed) {
2034 tty->print_cr("\nThe VMThreadStackSize specified is too small. "
2035 "Specify at least " SIZE_FORMAT "k",
2036 _vm_internal_thread_min_stack_allowed / K);
2037 return JNI_ERR;
2038 }
2039 return JNI_OK;
2040 }