1 /*
2 * Copyright (c) 1997, 2021, 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/guardedMemory.hpp"
42 #include "memory/resourceArea.hpp"
43 #include "memory/universe.hpp"
44 #include "oops/compressedKlass.hpp"
45 #include "oops/compressedOops.inline.hpp"
46 #include "oops/oop.inline.hpp"
47 #include "prims/jvm_misc.hpp"
48 #include "runtime/arguments.hpp"
49 #include "runtime/atomic.hpp"
50 #include "runtime/frame.inline.hpp"
51 #include "runtime/handles.inline.hpp"
52 #include "runtime/interfaceSupport.inline.hpp"
53 #include "runtime/java.hpp"
54 #include "runtime/javaCalls.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.inline.hpp"
60 #include "runtime/sharedRuntime.hpp"
61 #include "runtime/thread.inline.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 # include <signal.h>
78 # include <errno.h>
79
80 OSThread* os::_starting_thread = NULL;
81 address os::_polling_page = NULL;
82 volatile unsigned int os::_rand_seed = 1234567;
83 int os::_processor_count = 0;
84 int os::_initial_active_processor_count = 0;
85 os::PageSizes os::_page_sizes;
86
87 #ifndef PRODUCT
88 julong os::num_mallocs = 0; // # of calls to malloc/realloc
89 julong os::alloc_bytes = 0; // # of bytes allocated
90 julong os::num_frees = 0; // # of calls to free
91 julong os::free_bytes = 0; // # of bytes freed
92 #endif
93
94 static size_t cur_malloc_words = 0; // current size for MallocMaxTestWords
95
96 DEBUG_ONLY(bool os::_mutex_init_done = false;)
97
98 int os::snprintf(char* buf, size_t len, const char* fmt, ...) {
99 va_list args;
100 va_start(args, fmt);
101 int result = os::vsnprintf(buf, len, fmt, args);
102 va_end(args);
103 return result;
104 }
105
106 // Fill in buffer with current local time as an ISO-8601 string.
107 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz.
108 // Returns buffer, or NULL if it failed.
109 char* os::iso8601_time(char* buffer, size_t buffer_length, bool utc) {
110 const jlong now = javaTimeMillis();
111 return os::iso8601_time(now, buffer, buffer_length, utc);
112 }
113
114 // Fill in buffer with an ISO-8601 string corresponding to the given javaTimeMillis value
115 // E.g., yyyy-mm-ddThh:mm:ss-zzzz.
116 // Returns buffer, or NULL if it failed.
117 // This would mostly be a call to
118 // strftime(...., "%Y-%m-%d" "T" "%H:%M:%S" "%z", ....)
119 // except that on Windows the %z behaves badly, so we do it ourselves.
120 // Also, people wanted milliseconds on there,
121 // and strftime doesn't do milliseconds.
122 char* os::iso8601_time(jlong milliseconds_since_19700101, char* buffer, size_t buffer_length, bool utc) {
123 // Output will be of the form "YYYY-MM-DDThh:mm:ss.mmm+zzzz\0"
124
125 // Sanity check the arguments
126 if (buffer == NULL) {
127 assert(false, "NULL buffer");
128 return NULL;
129 }
130 if (buffer_length < os::iso8601_timestamp_size) {
131 assert(false, "buffer_length too small");
132 return NULL;
133 }
134 const int milliseconds_per_microsecond = 1000;
135 const time_t seconds_since_19700101 =
136 milliseconds_since_19700101 / milliseconds_per_microsecond;
137 const int milliseconds_after_second =
138 milliseconds_since_19700101 % milliseconds_per_microsecond;
139 // Convert the time value to a tm and timezone variable
140 struct tm time_struct;
141 if (utc) {
142 if (gmtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
143 assert(false, "Failed gmtime_pd");
144 return NULL;
145 }
146 } else {
147 if (localtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
148 assert(false, "Failed localtime_pd");
149 return NULL;
150 }
151 }
152
153 const time_t seconds_per_minute = 60;
154 const time_t minutes_per_hour = 60;
155 const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour;
156
157 // No offset when dealing with UTC
158 time_t UTC_to_local = 0;
159 if (!utc) {
160 #if defined(_ALLBSD_SOURCE) || defined(_GNU_SOURCE)
161 UTC_to_local = -(time_struct.tm_gmtoff);
162 #elif defined(_WINDOWS)
163 long zone;
164 _get_timezone(&zone);
165 UTC_to_local = static_cast<time_t>(zone);
166 #else
167 UTC_to_local = timezone;
168 #endif
169
170 // tm_gmtoff already includes adjustment for daylight saving
171 #if !defined(_ALLBSD_SOURCE) && !defined(_GNU_SOURCE)
172 // If daylight savings time is in effect,
173 // we are 1 hour East of our time zone
174 if (time_struct.tm_isdst > 0) {
175 UTC_to_local = UTC_to_local - seconds_per_hour;
176 }
177 #endif
178 }
179
180 // Compute the time zone offset.
181 // localtime_pd() sets timezone to the difference (in seconds)
182 // between UTC and and local time.
183 // ISO 8601 says we need the difference between local time and UTC,
184 // we change the sign of the localtime_pd() result.
185 const time_t local_to_UTC = -(UTC_to_local);
186 // Then we have to figure out if if we are ahead (+) or behind (-) UTC.
187 char sign_local_to_UTC = '+';
188 time_t abs_local_to_UTC = local_to_UTC;
189 if (local_to_UTC < 0) {
190 sign_local_to_UTC = '-';
191 abs_local_to_UTC = -(abs_local_to_UTC);
192 }
193 // Convert time zone offset seconds to hours and minutes.
194 const time_t zone_hours = (abs_local_to_UTC / seconds_per_hour);
195 const time_t zone_min =
196 ((abs_local_to_UTC % seconds_per_hour) / seconds_per_minute);
197
198 // Print an ISO 8601 date and time stamp into the buffer
199 const int year = 1900 + time_struct.tm_year;
200 const int month = 1 + time_struct.tm_mon;
201 const int printed = jio_snprintf(buffer, buffer_length,
202 "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d",
203 year,
204 month,
205 time_struct.tm_mday,
206 time_struct.tm_hour,
207 time_struct.tm_min,
208 time_struct.tm_sec,
209 milliseconds_after_second,
210 sign_local_to_UTC,
211 zone_hours,
212 zone_min);
213 if (printed == 0) {
214 assert(false, "Failed jio_printf");
215 return NULL;
216 }
217 return buffer;
218 }
219
220 OSReturn os::set_priority(Thread* thread, ThreadPriority p) {
221 debug_only(Thread::check_for_dangling_thread_pointer(thread);)
222
223 if ((p >= MinPriority && p <= MaxPriority) ||
224 (p == CriticalPriority && thread->is_ConcurrentGC_thread())) {
225 int priority = java_to_os_priority[p];
226 return set_native_priority(thread, priority);
227 } else {
228 assert(false, "Should not happen");
229 return OS_ERR;
230 }
231 }
232
233 // The mapping from OS priority back to Java priority may be inexact because
234 // Java priorities can map M:1 with native priorities. If you want the definite
235 // Java priority then use JavaThread::java_priority()
236 OSReturn os::get_priority(const Thread* const thread, ThreadPriority& priority) {
237 int p;
238 int os_prio;
239 OSReturn ret = get_native_priority(thread, &os_prio);
240 if (ret != OS_OK) return ret;
241
242 if (java_to_os_priority[MaxPriority] > java_to_os_priority[MinPriority]) {
243 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] > os_prio; p--) ;
244 } else {
245 // niceness values are in reverse order
246 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] < os_prio; p--) ;
247 }
248 priority = (ThreadPriority)p;
249 return OS_OK;
250 }
251
252 bool os::dll_build_name(char* buffer, size_t size, const char* fname) {
253 int n = jio_snprintf(buffer, size, "%s%s%s", JNI_LIB_PREFIX, fname, JNI_LIB_SUFFIX);
254 return (n != -1);
255 }
256
257 #if !defined(LINUX) && !defined(_WINDOWS)
258 bool os::committed_in_range(address start, size_t size, address& committed_start, size_t& committed_size) {
259 committed_start = start;
260 committed_size = size;
261 return true;
262 }
263 #endif
264
265 // Helper for dll_locate_lib.
266 // Pass buffer and printbuffer as we already printed the path to buffer
267 // when we called get_current_directory. This way we avoid another buffer
268 // of size MAX_PATH.
269 static bool conc_path_file_and_check(char *buffer, char *printbuffer, size_t printbuflen,
270 const char* pname, char lastchar, const char* fname) {
271
272 // Concatenate path and file name, but don't print double path separators.
273 const char *filesep = (WINDOWS_ONLY(lastchar == ':' ||) lastchar == os::file_separator()[0]) ?
274 "" : os::file_separator();
275 int ret = jio_snprintf(printbuffer, printbuflen, "%s%s%s", pname, filesep, fname);
276 // Check whether file exists.
277 if (ret != -1) {
278 struct stat statbuf;
279 return os::stat(buffer, &statbuf) == 0;
280 }
281 return false;
282 }
283
284 // Frees all memory allocated on the heap for the
285 // supplied array of arrays of chars (a), where n
286 // is the number of elements in the array.
287 static void free_array_of_char_arrays(char** a, size_t n) {
288 while (n > 0) {
289 n--;
290 if (a[n] != NULL) {
291 FREE_C_HEAP_ARRAY(char, a[n]);
292 }
293 }
294 FREE_C_HEAP_ARRAY(char*, a);
295 }
296
297 bool os::dll_locate_lib(char *buffer, size_t buflen,
298 const char* pname, const char* fname) {
299 bool retval = false;
300
301 size_t fullfnamelen = strlen(JNI_LIB_PREFIX) + strlen(fname) + strlen(JNI_LIB_SUFFIX);
302 char* fullfname = NEW_C_HEAP_ARRAY(char, fullfnamelen + 1, mtInternal);
303 if (dll_build_name(fullfname, fullfnamelen + 1, fname)) {
304 const size_t pnamelen = pname ? strlen(pname) : 0;
305
306 if (pnamelen == 0) {
307 // If no path given, use current working directory.
308 const char* p = get_current_directory(buffer, buflen);
309 if (p != NULL) {
310 const size_t plen = strlen(buffer);
311 const char lastchar = buffer[plen - 1];
312 retval = conc_path_file_and_check(buffer, &buffer[plen], buflen - plen,
313 "", lastchar, fullfname);
314 }
315 } else if (strchr(pname, *os::path_separator()) != NULL) {
316 // A list of paths. Search for the path that contains the library.
317 size_t n;
318 char** pelements = split_path(pname, &n, fullfnamelen);
319 if (pelements != NULL) {
320 for (size_t i = 0; i < n; i++) {
321 char* path = pelements[i];
322 // Really shouldn't be NULL, but check can't hurt.
323 size_t plen = (path == NULL) ? 0 : strlen(path);
324 if (plen == 0) {
325 continue; // Skip the empty path values.
326 }
327 const char lastchar = path[plen - 1];
328 retval = conc_path_file_and_check(buffer, buffer, buflen, path, lastchar, fullfname);
329 if (retval) break;
330 }
331 // Release the storage allocated by split_path.
332 free_array_of_char_arrays(pelements, n);
333 }
334 } else {
335 // A definite path.
336 const char lastchar = pname[pnamelen-1];
337 retval = conc_path_file_and_check(buffer, buffer, buflen, pname, lastchar, fullfname);
338 }
339 }
340
341 FREE_C_HEAP_ARRAY(char*, fullfname);
342 return retval;
343 }
344
345 // --------------------- sun.misc.Signal (optional) ---------------------
346
347
348 // SIGBREAK is sent by the keyboard to query the VM state
349 #ifndef SIGBREAK
350 #define SIGBREAK SIGQUIT
351 #endif
352
353 // sigexitnum_pd is a platform-specific special signal used for terminating the Signal thread.
354
355
356 static void signal_thread_entry(JavaThread* thread, TRAPS) {
357 os::set_priority(thread, NearMaxPriority);
358 while (true) {
359 int sig;
360 {
361 // FIXME : Currently we have not decided what should be the status
362 // for this java thread blocked here. Once we decide about
363 // that we should fix this.
364 sig = os::signal_wait();
365 }
366 if (sig == os::sigexitnum_pd()) {
367 // Terminate the signal thread
368 return;
369 }
370
371 switch (sig) {
372 case SIGBREAK: {
373 #if INCLUDE_SERVICES
374 // Check if the signal is a trigger to start the Attach Listener - in that
375 // case don't print stack traces.
376 if (!DisableAttachMechanism) {
377 // Attempt to transit state to AL_INITIALIZING.
378 AttachListenerState cur_state = AttachListener::transit_state(AL_INITIALIZING, AL_NOT_INITIALIZED);
379 if (cur_state == AL_INITIALIZING) {
380 // Attach Listener has been started to initialize. Ignore this signal.
381 continue;
382 } else if (cur_state == AL_NOT_INITIALIZED) {
383 // Start to initialize.
384 if (AttachListener::is_init_trigger()) {
385 // Attach Listener has been initialized.
386 // Accept subsequent request.
387 continue;
388 } else {
389 // Attach Listener could not be started.
390 // So we need to transit the state to AL_NOT_INITIALIZED.
391 AttachListener::set_state(AL_NOT_INITIALIZED);
392 }
393 } else if (AttachListener::check_socket_file()) {
394 // Attach Listener has been started, but unix domain socket file
395 // does not exist. So restart Attach Listener.
396 continue;
397 }
398 }
399 #endif
400 // Print stack traces
401 // Any SIGBREAK operations added here should make sure to flush
402 // the output stream (e.g. tty->flush()) after output. See 4803766.
403 // Each module also prints an extra carriage return after its output.
404 VM_PrintThreads op(tty, PrintConcurrentLocks, false /* no extended info */, true /* print JNI handle info */);
405 VMThread::execute(&op);
406 VM_FindDeadlocks op1(tty);
407 VMThread::execute(&op1);
408 Universe::print_heap_at_SIGBREAK();
409 if (PrintClassHistogram) {
410 VM_GC_HeapInspection op1(tty, true /* force full GC before heap inspection */);
411 VMThread::execute(&op1);
412 }
413 if (JvmtiExport::should_post_data_dump()) {
414 JvmtiExport::post_data_dump();
415 }
416 break;
417 }
418 default: {
419 // Dispatch the signal to java
420 HandleMark hm(THREAD);
421 Klass* klass = SystemDictionary::resolve_or_null(vmSymbols::jdk_internal_misc_Signal(), THREAD);
422 if (klass != NULL) {
423 JavaValue result(T_VOID);
424 JavaCallArguments args;
425 args.push_int(sig);
426 JavaCalls::call_static(
427 &result,
428 klass,
429 vmSymbols::dispatch_name(),
430 vmSymbols::int_void_signature(),
431 &args,
432 THREAD
433 );
434 }
435 if (HAS_PENDING_EXCEPTION) {
436 // tty is initialized early so we don't expect it to be null, but
437 // if it is we can't risk doing an initialization that might
438 // trigger additional out-of-memory conditions
439 if (tty != NULL) {
440 char klass_name[256];
441 char tmp_sig_name[16];
442 const char* sig_name = "UNKNOWN";
443 InstanceKlass::cast(PENDING_EXCEPTION->klass())->
444 name()->as_klass_external_name(klass_name, 256);
445 if (os::exception_name(sig, tmp_sig_name, 16) != NULL)
446 sig_name = tmp_sig_name;
447 warning("Exception %s occurred dispatching signal %s to handler"
448 "- the VM may need to be forcibly terminated",
449 klass_name, sig_name );
450 }
451 CLEAR_PENDING_EXCEPTION;
452 }
453 }
454 }
455 }
456 }
457
458 void os::init_before_ergo() {
459 initialize_initial_active_processor_count();
460 // We need to initialize large page support here because ergonomics takes some
461 // decisions depending on large page support and the calculated large page size.
462 large_page_init();
463
464 StackOverflow::initialize_stack_zone_sizes();
465
466 // VM version initialization identifies some characteristics of the
467 // platform that are used during ergonomic decisions.
468 VM_Version::init_before_ergo();
469 }
470
471 void os::initialize_jdk_signal_support(TRAPS) {
472 if (!ReduceSignalUsage) {
473 // Setup JavaThread for processing signals
474 const char* name = "Signal Dispatcher";
475 Handle thread_oop = JavaThread::create_system_thread_object(name, true /* visible */, CHECK);
476
477 JavaThread* thread = new JavaThread(&signal_thread_entry);
478 JavaThread::vm_exit_on_osthread_failure(thread);
479
480 JavaThread::start_internal_daemon(THREAD, thread, thread_oop, NearMaxPriority);
481
482 // Handle ^BREAK
483 os::signal(SIGBREAK, os::user_handler());
484 }
485 }
486
487
488 void os::terminate_signal_thread() {
489 if (!ReduceSignalUsage)
490 signal_notify(sigexitnum_pd());
491 }
492
493
494 // --------------------- loading libraries ---------------------
495
496 typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *);
497 extern struct JavaVM_ main_vm;
498
499 static void* _native_java_library = NULL;
500
501 void* os::native_java_library() {
502 if (_native_java_library == NULL) {
503 char buffer[JVM_MAXPATHLEN];
504 char ebuf[1024];
505
506 // Load java dll
507 if (dll_locate_lib(buffer, sizeof(buffer), Arguments::get_dll_dir(),
508 "java")) {
509 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf));
510 }
511 if (_native_java_library == NULL) {
512 vm_exit_during_initialization("Unable to load native library", ebuf);
513 }
514
515 #if defined(__OpenBSD__)
516 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so
517 // ignore errors
518 if (dll_locate_lib(buffer, sizeof(buffer), Arguments::get_dll_dir(),
519 "net")) {
520 dll_load(buffer, ebuf, sizeof(ebuf));
521 }
522 #endif
523 }
524 return _native_java_library;
525 }
526
527 /*
528 * Support for finding Agent_On(Un)Load/Attach<_lib_name> if it exists.
529 * If check_lib == true then we are looking for an
530 * Agent_OnLoad_lib_name or Agent_OnAttach_lib_name function to determine if
531 * this library is statically linked into the image.
532 * If check_lib == false then we will look for the appropriate symbol in the
533 * executable if agent_lib->is_static_lib() == true or in the shared library
534 * referenced by 'handle'.
535 */
536 void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib,
537 const char *syms[], size_t syms_len) {
538 assert(agent_lib != NULL, "sanity check");
539 const char *lib_name;
540 void *handle = agent_lib->os_lib();
541 void *entryName = NULL;
542 char *agent_function_name;
543 size_t i;
544
545 // If checking then use the agent name otherwise test is_static_lib() to
546 // see how to process this lookup
547 lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL);
548 for (i = 0; i < syms_len; i++) {
549 agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path());
550 if (agent_function_name == NULL) {
551 break;
552 }
553 entryName = dll_lookup(handle, agent_function_name);
554 FREE_C_HEAP_ARRAY(char, agent_function_name);
555 if (entryName != NULL) {
556 break;
557 }
558 }
559 return entryName;
560 }
561
562 // See if the passed in agent is statically linked into the VM image.
563 bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
564 size_t syms_len) {
565 void *ret;
566 void *proc_handle;
567 void *save_handle;
568
569 assert(agent_lib != NULL, "sanity check");
570 if (agent_lib->name() == NULL) {
571 return false;
572 }
573 proc_handle = get_default_process_handle();
574 // Check for Agent_OnLoad/Attach_lib_name function
575 save_handle = agent_lib->os_lib();
576 // We want to look in this process' symbol table.
577 agent_lib->set_os_lib(proc_handle);
578 ret = find_agent_function(agent_lib, true, syms, syms_len);
579 if (ret != NULL) {
580 // Found an entry point like Agent_OnLoad_lib_name so we have a static agent
581 agent_lib->set_valid();
582 agent_lib->set_static_lib(true);
583 return true;
584 }
585 agent_lib->set_os_lib(save_handle);
586 return false;
587 }
588
589 // --------------------- heap allocation utilities ---------------------
590
591 char *os::strdup(const char *str, MEMFLAGS flags) {
592 size_t size = strlen(str);
593 char *dup_str = (char *)malloc(size + 1, flags);
594 if (dup_str == NULL) return NULL;
595 strcpy(dup_str, str);
596 return dup_str;
597 }
598
599 char* os::strdup_check_oom(const char* str, MEMFLAGS flags) {
600 char* p = os::strdup(str, flags);
601 if (p == NULL) {
602 vm_exit_out_of_memory(strlen(str) + 1, OOM_MALLOC_ERROR, "os::strdup_check_oom");
603 }
604 return p;
605 }
606
607
608 #define paranoid 0 /* only set to 1 if you suspect checking code has bug */
609
610 #ifdef ASSERT
611
612 static void verify_memory(void* ptr) {
613 GuardedMemory guarded(ptr);
614 if (!guarded.verify_guards()) {
615 LogTarget(Warning, malloc, free) lt;
616 ResourceMark rm;
617 LogStream ls(lt);
618 ls.print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees);
619 ls.print_cr("## memory stomp:");
620 guarded.print_on(&ls);
621 fatal("memory stomping error");
622 }
623 }
624
625 #endif
626
627 //
628 // This function supports testing of the malloc out of memory
629 // condition without really running the system out of memory.
630 //
631 static bool has_reached_max_malloc_test_peak(size_t alloc_size) {
632 if (MallocMaxTestWords > 0) {
633 size_t words = (alloc_size / BytesPerWord);
634
635 if ((cur_malloc_words + words) > MallocMaxTestWords) {
636 return true;
637 }
638 Atomic::add(&cur_malloc_words, words);
639 }
640 return false;
641 }
642
643 void* os::malloc(size_t size, MEMFLAGS flags) {
644 return os::malloc(size, flags, CALLER_PC);
645 }
646
647 void* os::malloc(size_t size, MEMFLAGS memflags, const NativeCallStack& stack) {
648 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
649 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
650
651 #if INCLUDE_NMT
652 {
653 void* rc = NULL;
654 if (NMTPreInit::handle_malloc(&rc, size)) {
655 return rc;
656 }
657 }
658 #endif
659
660 // Since os::malloc can be called when the libjvm.{dll,so} is
661 // first loaded and we don't have a thread yet we must accept NULL also here.
662 assert(!os::ThreadCrashProtection::is_crash_protected(Thread::current_or_null()),
663 "malloc() not allowed when crash protection is set");
664
665 if (size == 0) {
666 // return a valid pointer if size is zero
667 // if NULL is returned the calling functions assume out of memory.
668 size = 1;
669 }
670
671 // NMT support
672 NMT_TrackingLevel level = MemTracker::tracking_level();
673 const size_t nmt_overhead =
674 MemTracker::malloc_header_size(level) + MemTracker::malloc_footer_size(level);
675
676 #ifndef ASSERT
677 const size_t alloc_size = size + nmt_overhead;
678 #else
679 const size_t alloc_size = GuardedMemory::get_total_size(size + nmt_overhead);
680 if (size + nmt_overhead > alloc_size) { // Check for rollover.
681 return NULL;
682 }
683 #endif
684
685 // For the test flag -XX:MallocMaxTestWords
686 if (has_reached_max_malloc_test_peak(size)) {
687 return NULL;
688 }
689
690 u_char* ptr;
691 ptr = (u_char*)::malloc(alloc_size);
692
693 #ifdef ASSERT
694 if (ptr == NULL) {
695 return NULL;
696 }
697 // Wrap memory with guard
698 GuardedMemory guarded(ptr, size + nmt_overhead);
699 ptr = guarded.get_user_ptr();
700
701 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) {
702 log_warning(malloc, free)("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr));
703 breakpoint();
704 }
705 if (paranoid) {
706 verify_memory(ptr);
707 }
708 #endif
709
710 // we do not track guard memory
711 return MemTracker::record_malloc((address)ptr, size, memflags, stack, level);
712 }
713
714 void* os::realloc(void *memblock, size_t size, MEMFLAGS flags) {
715 return os::realloc(memblock, size, flags, CALLER_PC);
716 }
717
718 void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, const NativeCallStack& stack) {
719
720 #if INCLUDE_NMT
721 {
722 void* rc = NULL;
723 if (NMTPreInit::handle_realloc(&rc, memblock, size)) {
724 return rc;
725 }
726 }
727 #endif
728
729 // For the test flag -XX:MallocMaxTestWords
730 if (has_reached_max_malloc_test_peak(size)) {
731 return NULL;
732 }
733
734 if (size == 0) {
735 // return a valid pointer if size is zero
736 // if NULL is returned the calling functions assume out of memory.
737 size = 1;
738 }
739
740 #ifndef ASSERT
741 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
742 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
743 // NMT support
744 NMT_TrackingLevel level = MemTracker::tracking_level();
745 void* membase = MemTracker::record_free(memblock, level);
746 const size_t nmt_overhead =
747 MemTracker::malloc_header_size(level) + MemTracker::malloc_footer_size(level);
748 void* ptr = ::realloc(membase, size + nmt_overhead);
749 return MemTracker::record_malloc(ptr, size, memflags, stack, level);
750 #else
751 if (memblock == NULL) {
752 return os::malloc(size, memflags, stack);
753 }
754 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
755 log_warning(malloc, free)("os::realloc caught " PTR_FORMAT, p2i(memblock));
756 breakpoint();
757 }
758 // NMT support
759 void* membase = MemTracker::malloc_base(memblock);
760 verify_memory(membase);
761 // always move the block
762 void* ptr = os::malloc(size, memflags, stack);
763 // Copy to new memory if malloc didn't fail
764 if (ptr != NULL ) {
765 GuardedMemory guarded(MemTracker::malloc_base(memblock));
766 // Guard's user data contains NMT header
767 NMT_TrackingLevel level = MemTracker::tracking_level();
768 const size_t nmt_overhead =
769 MemTracker::malloc_header_size(level) + MemTracker::malloc_footer_size(level);
770 size_t memblock_size = guarded.get_user_size() - nmt_overhead;
771 memcpy(ptr, memblock, MIN2(size, memblock_size));
772 if (paranoid) {
773 verify_memory(MemTracker::malloc_base(ptr));
774 }
775 os::free(memblock);
776 }
777 return ptr;
778 #endif
779 }
780
781 // handles NULL pointers
782 void os::free(void *memblock) {
783
784 #if INCLUDE_NMT
785 if (NMTPreInit::handle_free(memblock)) {
786 return;
787 }
788 #endif
789
790 NOT_PRODUCT(inc_stat_counter(&num_frees, 1));
791 #ifdef ASSERT
792 if (memblock == NULL) return;
793 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
794 log_warning(malloc, free)("os::free caught " PTR_FORMAT, p2i(memblock));
795 breakpoint();
796 }
797 void* membase = MemTracker::record_free(memblock, MemTracker::tracking_level());
798 verify_memory(membase);
799
800 GuardedMemory guarded(membase);
801 size_t size = guarded.get_user_size();
802 inc_stat_counter(&free_bytes, size);
803 membase = guarded.release_for_freeing();
804 ::free(membase);
805 #else
806 void* membase = MemTracker::record_free(memblock, MemTracker::tracking_level());
807 ::free(membase);
808 #endif
809 }
810
811 void os::init_random(unsigned int initval) {
812 _rand_seed = initval;
813 }
814
815
816 int os::next_random(unsigned int rand_seed) {
817 /* standard, well-known linear congruential random generator with
818 * next_rand = (16807*seed) mod (2**31-1)
819 * see
820 * (1) "Random Number Generators: Good Ones Are Hard to Find",
821 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988),
822 * (2) "Two Fast Implementations of the 'Minimal Standard' Random
823 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88.
824 */
825 const unsigned int a = 16807;
826 const unsigned int m = 2147483647;
827 const int q = m / a; assert(q == 127773, "weird math");
828 const int r = m % a; assert(r == 2836, "weird math");
829
830 // compute az=2^31p+q
831 unsigned int lo = a * (rand_seed & 0xFFFF);
832 unsigned int hi = a * (rand_seed >> 16);
833 lo += (hi & 0x7FFF) << 16;
834
835 // if q overflowed, ignore the overflow and increment q
836 if (lo > m) {
837 lo &= m;
838 ++lo;
839 }
840 lo += hi >> 15;
841
842 // if (p+q) overflowed, ignore the overflow and increment (p+q)
843 if (lo > m) {
844 lo &= m;
845 ++lo;
846 }
847 return lo;
848 }
849
850 int os::random() {
851 // Make updating the random seed thread safe.
852 while (true) {
853 unsigned int seed = _rand_seed;
854 unsigned int rand = next_random(seed);
855 if (Atomic::cmpxchg(&_rand_seed, seed, rand, memory_order_relaxed) == seed) {
856 return static_cast<int>(rand);
857 }
858 }
859 }
860
861 // The INITIALIZED state is distinguished from the SUSPENDED state because the
862 // conditions in which a thread is first started are different from those in which
863 // a suspension is resumed. These differences make it hard for us to apply the
864 // tougher checks when starting threads that we want to do when resuming them.
865 // However, when start_thread is called as a result of Thread.start, on a Java
866 // thread, the operation is synchronized on the Java Thread object. So there
867 // cannot be a race to start the thread and hence for the thread to exit while
868 // we are working on it. Non-Java threads that start Java threads either have
869 // to do so in a context in which races are impossible, or should do appropriate
870 // locking.
871
872 void os::start_thread(Thread* thread) {
873 OSThread* osthread = thread->osthread();
874 osthread->set_state(RUNNABLE);
875 pd_start_thread(thread);
876 }
877
878 void os::abort(bool dump_core) {
879 abort(dump_core && CreateCoredumpOnCrash, NULL, NULL);
880 }
881
882 //---------------------------------------------------------------------------
883 // Helper functions for fatal error handler
884
885 bool os::print_function_and_library_name(outputStream* st,
886 address addr,
887 char* buf, int buflen,
888 bool shorten_paths,
889 bool demangle,
890 bool strip_arguments) {
891 // If no scratch buffer given, allocate one here on stack.
892 // (used during error handling; its a coin toss, really, if on-stack allocation
893 // is worse than (raw) C-heap allocation in that case).
894 char* p = buf;
895 if (p == NULL) {
896 p = (char*)::alloca(O_BUFLEN);
897 buflen = O_BUFLEN;
898 }
899 int offset = 0;
900 bool have_function_name = dll_address_to_function_name(addr, p, buflen,
901 &offset, demangle);
902 bool is_function_descriptor = false;
903 #ifdef HAVE_FUNCTION_DESCRIPTORS
904 // When we deal with a function descriptor instead of a real code pointer, try to
905 // resolve it. There is a small chance that a random pointer given to this function
906 // may just happen to look like a valid descriptor, but this is rare and worth the
907 // risk to see resolved function names. But we will print a little suffix to mark
908 // this as a function descriptor for the reader (see below).
909 if (!have_function_name && os::is_readable_pointer(addr)) {
910 address addr2 = (address)os::resolve_function_descriptor(addr);
911 if (have_function_name = is_function_descriptor =
912 dll_address_to_function_name(addr2, p, buflen, &offset, demangle)) {
913 addr = addr2;
914 }
915 }
916 #endif // HAVE_FUNCTION_DESCRIPTORS
917
918 if (have_function_name) {
919 // Print function name, optionally demangled
920 if (demangle && strip_arguments) {
921 char* args_start = strchr(p, '(');
922 if (args_start != NULL) {
923 *args_start = '\0';
924 }
925 }
926 // Print offset. Omit printing if offset is zero, which makes the output
927 // more readable if we print function pointers.
928 if (offset == 0) {
929 st->print("%s", p);
930 } else {
931 st->print("%s+%d", p, offset);
932 }
933 } else {
934 st->print(PTR_FORMAT, p2i(addr));
935 }
936 offset = 0;
937
938 const bool have_library_name = dll_address_to_library_name(addr, p, buflen, &offset);
939 if (have_library_name) {
940 // Cut path parts
941 if (shorten_paths) {
942 char* p2 = strrchr(p, os::file_separator()[0]);
943 if (p2 != NULL) {
944 p = p2 + 1;
945 }
946 }
947 st->print(" in %s", p);
948 if (!have_function_name) { // Omit offset if we already printed the function offset
949 st->print("+%d", offset);
950 }
951 }
952
953 // Write a trailing marker if this was a function descriptor
954 if (have_function_name && is_function_descriptor) {
955 st->print_raw(" (FD)");
956 }
957
958 return have_function_name || have_library_name;
959 }
960
961 void os::print_hex_dump(outputStream* st, address start, address end, int unitsize,
962 int bytes_per_line, address logical_start) {
963 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking");
964
965 start = align_down(start, unitsize);
966 logical_start = align_down(logical_start, unitsize);
967 bytes_per_line = align_up(bytes_per_line, 8);
968
969 int cols = 0;
970 int cols_per_line = bytes_per_line / unitsize;
971
972 address p = start;
973 address logical_p = logical_start;
974
975 // Print out the addresses as if we were starting from logical_start.
976 st->print(PTR_FORMAT ": ", p2i(logical_p));
977 while (p < end) {
978 if (is_readable_pointer(p)) {
979 switch (unitsize) {
980 case 1: st->print("%02x", *(u1*)p); break;
981 case 2: st->print("%04x", *(u2*)p); break;
982 case 4: st->print("%08x", *(u4*)p); break;
983 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break;
984 }
985 } else {
986 st->print("%*.*s", 2*unitsize, 2*unitsize, "????????????????");
987 }
988 p += unitsize;
989 logical_p += unitsize;
990 cols++;
991 if (cols >= cols_per_line && p < end) {
992 cols = 0;
993 st->cr();
994 st->print(PTR_FORMAT ": ", p2i(logical_p));
995 } else {
996 st->print(" ");
997 }
998 }
999 st->cr();
1000 }
1001
1002 void os::print_dhm(outputStream* st, const char* startStr, long sec) {
1003 long days = sec/86400;
1004 long hours = (sec/3600) - (days * 24);
1005 long minutes = (sec/60) - (days * 1440) - (hours * 60);
1006 if (startStr == NULL) startStr = "";
1007 st->print_cr("%s %ld days %ld:%02ld hours", startStr, days, hours, minutes);
1008 }
1009
1010 void os::print_instructions(outputStream* st, address pc, int unitsize) {
1011 st->print_cr("Instructions: (pc=" PTR_FORMAT ")", p2i(pc));
1012 print_hex_dump(st, pc - 256, pc + 256, unitsize);
1013 }
1014
1015 void os::print_environment_variables(outputStream* st, const char** env_list) {
1016 if (env_list) {
1017 st->print_cr("Environment Variables:");
1018
1019 for (int i = 0; env_list[i] != NULL; i++) {
1020 char *envvar = ::getenv(env_list[i]);
1021 if (envvar != NULL) {
1022 st->print("%s", env_list[i]);
1023 st->print("=");
1024 st->print("%s", envvar);
1025 // Use separate cr() printing to avoid unnecessary buffer operations that might cause truncation.
1026 st->cr();
1027 }
1028 }
1029 }
1030 }
1031
1032 void os::print_cpu_info(outputStream* st, char* buf, size_t buflen) {
1033 // cpu
1034 st->print("CPU:");
1035 #if defined(__APPLE__) && !defined(ZERO)
1036 if (VM_Version::is_cpu_emulated()) {
1037 st->print(" (EMULATED)");
1038 }
1039 #endif
1040 st->print(" total %d", os::processor_count());
1041 // It's not safe to query number of active processors after crash
1042 // st->print("(active %d)", os::active_processor_count()); but we can
1043 // print the initial number of active processors.
1044 // We access the raw value here because the assert in the accessor will
1045 // fail if the crash occurs before initialization of this value.
1046 st->print(" (initial active %d)", _initial_active_processor_count);
1047 st->print(" %s", VM_Version::features_string());
1048 st->cr();
1049 pd_print_cpu_info(st, buf, buflen);
1050 }
1051
1052 // Print a one line string summarizing the cpu, number of cores, memory, and operating system version
1053 void os::print_summary_info(outputStream* st, char* buf, size_t buflen) {
1054 st->print("Host: ");
1055 #ifndef PRODUCT
1056 if (get_host_name(buf, buflen)) {
1057 st->print("%s, ", buf);
1058 }
1059 #endif // PRODUCT
1060 get_summary_cpu_info(buf, buflen);
1061 st->print("%s, ", buf);
1062 size_t mem = physical_memory()/G;
1063 if (mem == 0) { // for low memory systems
1064 mem = physical_memory()/M;
1065 st->print("%d cores, " SIZE_FORMAT "M, ", processor_count(), mem);
1066 } else {
1067 st->print("%d cores, " SIZE_FORMAT "G, ", processor_count(), mem);
1068 }
1069 get_summary_os_info(buf, buflen);
1070 st->print_raw(buf);
1071 st->cr();
1072 }
1073
1074 void os::print_date_and_time(outputStream *st, char* buf, size_t buflen) {
1075 const int secs_per_day = 86400;
1076 const int secs_per_hour = 3600;
1077 const int secs_per_min = 60;
1078
1079 time_t tloc;
1080 (void)time(&tloc);
1081 char* timestring = ctime(&tloc); // ctime adds newline.
1082 // edit out the newline
1083 char* nl = strchr(timestring, '\n');
1084 if (nl != NULL) {
1085 *nl = '\0';
1086 }
1087
1088 struct tm tz;
1089 if (localtime_pd(&tloc, &tz) != NULL) {
1090 wchar_t w_buf[80];
1091 size_t n = ::wcsftime(w_buf, 80, L"%Z", &tz);
1092 if (n > 0) {
1093 ::wcstombs(buf, w_buf, buflen);
1094 st->print("Time: %s %s", timestring, buf);
1095 } else {
1096 st->print("Time: %s", timestring);
1097 }
1098 } else {
1099 st->print("Time: %s", timestring);
1100 }
1101
1102 double t = os::elapsedTime();
1103 // NOTE: a crash using printf("%f",...) on Linux was historically noted here.
1104 int eltime = (int)t; // elapsed time in seconds
1105 int eltimeFraction = (int) ((t - eltime) * 1000000);
1106
1107 // print elapsed time in a human-readable format:
1108 int eldays = eltime / secs_per_day;
1109 int day_secs = eldays * secs_per_day;
1110 int elhours = (eltime - day_secs) / secs_per_hour;
1111 int hour_secs = elhours * secs_per_hour;
1112 int elmins = (eltime - day_secs - hour_secs) / secs_per_min;
1113 int minute_secs = elmins * secs_per_min;
1114 int elsecs = (eltime - day_secs - hour_secs - minute_secs);
1115 st->print_cr(" elapsed time: %d.%06d seconds (%dd %dh %dm %ds)", eltime, eltimeFraction, eldays, elhours, elmins, elsecs);
1116 }
1117
1118
1119 // Check if pointer can be read from (4-byte read access).
1120 // Helps to prove validity of a not-NULL pointer.
1121 // Returns true in very early stages of VM life when stub is not yet generated.
1122 #define SAFEFETCH_DEFAULT true
1123 bool os::is_readable_pointer(const void* p) {
1124 if (!CanUseSafeFetch32()) {
1125 return SAFEFETCH_DEFAULT;
1126 }
1127 int* const aligned = (int*) align_down((intptr_t)p, 4);
1128 int cafebabe = 0xcafebabe; // tester value 1
1129 int deadbeef = 0xdeadbeef; // tester value 2
1130 return (SafeFetch32(aligned, cafebabe) != cafebabe) || (SafeFetch32(aligned, deadbeef) != deadbeef);
1131 }
1132
1133 bool os::is_readable_range(const void* from, const void* to) {
1134 if ((uintptr_t)from >= (uintptr_t)to) return false;
1135 for (uintptr_t p = align_down((uintptr_t)from, min_page_size()); p < (uintptr_t)to; p += min_page_size()) {
1136 if (!is_readable_pointer((const void*)p)) {
1137 return false;
1138 }
1139 }
1140 return true;
1141 }
1142
1143
1144 // moved from debug.cpp (used to be find()) but still called from there
1145 // The verbose parameter is only set by the debug code in one case
1146 void os::print_location(outputStream* st, intptr_t x, bool verbose) {
1147 address addr = (address)x;
1148 // Handle NULL first, so later checks don't need to protect against it.
1149 if (addr == NULL) {
1150 st->print_cr("0x0 is NULL");
1151 return;
1152 }
1153
1154 // Check if addr points into a code blob.
1155 CodeBlob* b = CodeCache::find_blob_unsafe(addr);
1156 if (b != NULL) {
1157 b->dump_for_addr(addr, st, verbose);
1158 return;
1159 }
1160
1161 // Check if addr points into Java heap.
1162 if (Universe::heap()->print_location(st, addr)) {
1163 return;
1164 }
1165
1166 bool accessible = is_readable_pointer(addr);
1167
1168 // Check if addr is a JNI handle.
1169 if (align_down((intptr_t)addr, sizeof(intptr_t)) != 0 && accessible) {
1170 if (JNIHandles::is_global_handle((jobject) addr)) {
1171 st->print_cr(INTPTR_FORMAT " is a global jni handle", p2i(addr));
1172 return;
1173 }
1174 if (JNIHandles::is_weak_global_handle((jobject) addr)) {
1175 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", p2i(addr));
1176 return;
1177 }
1178 }
1179
1180 // Check if addr belongs to a Java thread.
1181 for (JavaThreadIteratorWithHandle jtiwh; JavaThread *thread = jtiwh.next(); ) {
1182 // If the addr is a java thread print information about that.
1183 if (addr == (address)thread) {
1184 if (verbose) {
1185 thread->print_on(st);
1186 } else {
1187 st->print_cr(INTPTR_FORMAT " is a thread", p2i(addr));
1188 }
1189 return;
1190 }
1191 // If the addr is in the stack region for this thread then report that
1192 // and print thread info
1193 if (thread->is_in_full_stack(addr)) {
1194 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: "
1195 INTPTR_FORMAT, p2i(addr), p2i(thread));
1196 if (verbose) thread->print_on(st);
1197 return;
1198 }
1199 }
1200
1201 // Check if in metaspace and print types that have vptrs
1202 if (Metaspace::contains(addr)) {
1203 if (Klass::is_valid((Klass*)addr)) {
1204 st->print_cr(INTPTR_FORMAT " is a pointer to class: ", p2i(addr));
1205 ((Klass*)addr)->print_on(st);
1206 } else if (Method::is_valid_method((const Method*)addr)) {
1207 ((Method*)addr)->print_value_on(st);
1208 st->cr();
1209 } else {
1210 // Use addr->print() from the debugger instead (not here)
1211 st->print_cr(INTPTR_FORMAT " is pointing into metadata", p2i(addr));
1212 }
1213 return;
1214 }
1215
1216 // Compressed klass needs to be decoded first.
1217 #ifdef _LP64
1218 if (UseCompressedClassPointers && ((uintptr_t)addr &~ (uintptr_t)max_juint) == 0) {
1219 narrowKlass narrow_klass = (narrowKlass)(uintptr_t)addr;
1220 Klass* k = CompressedKlassPointers::decode_raw(narrow_klass);
1221
1222 if (Klass::is_valid(k)) {
1223 st->print_cr(UINT32_FORMAT " is a compressed pointer to class: " INTPTR_FORMAT, narrow_klass, p2i((HeapWord*)k));
1224 k->print_on(st);
1225 return;
1226 }
1227 }
1228 #endif
1229
1230 // Try an OS specific find
1231 if (os::find(addr, st)) {
1232 return;
1233 }
1234
1235 if (accessible) {
1236 st->print(INTPTR_FORMAT " points into unknown readable memory:", p2i(addr));
1237 if (is_aligned(addr, sizeof(intptr_t))) {
1238 st->print(" " PTR_FORMAT " |", *(intptr_t*)addr);
1239 }
1240 for (address p = addr; p < align_up(addr + 1, sizeof(intptr_t)); ++p) {
1241 st->print(" %02x", *(u1*)p);
1242 }
1243 st->cr();
1244 return;
1245 }
1246
1247 st->print_cr(INTPTR_FORMAT " is an unknown value", p2i(addr));
1248 }
1249
1250 // Looks like all platforms can use the same function to check if C
1251 // stack is walkable beyond current frame.
1252 bool os::is_first_C_frame(frame* fr) {
1253
1254 #ifdef _WINDOWS
1255 return true; // native stack isn't walkable on windows this way.
1256 #endif
1257
1258 // Load up sp, fp, sender sp and sender fp, check for reasonable values.
1259 // Check usp first, because if that's bad the other accessors may fault
1260 // on some architectures. Ditto ufp second, etc.
1261 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1);
1262 // sp on amd can be 32 bit aligned.
1263 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1);
1264
1265 uintptr_t usp = (uintptr_t)fr->sp();
1266 if ((usp & sp_align_mask) != 0) return true;
1267
1268 uintptr_t ufp = (uintptr_t)fr->fp();
1269 if ((ufp & fp_align_mask) != 0) return true;
1270
1271 uintptr_t old_sp = (uintptr_t)fr->sender_sp();
1272 if ((old_sp & sp_align_mask) != 0) return true;
1273 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true;
1274
1275 uintptr_t old_fp = (uintptr_t)fr->link();
1276 if ((old_fp & fp_align_mask) != 0) return true;
1277 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true;
1278
1279 // stack grows downwards; if old_fp is below current fp or if the stack
1280 // frame is too large, either the stack is corrupted or fp is not saved
1281 // on stack (i.e. on x86, ebp may be used as general register). The stack
1282 // is not walkable beyond current frame.
1283 if (old_fp < ufp) return true;
1284 if (old_fp - ufp > 64 * K) return true;
1285
1286 return false;
1287 }
1288
1289
1290 // Set up the boot classpath.
1291
1292 char* os::format_boot_path(const char* format_string,
1293 const char* home,
1294 int home_len,
1295 char fileSep,
1296 char pathSep) {
1297 assert((fileSep == '/' && pathSep == ':') ||
1298 (fileSep == '\\' && pathSep == ';'), "unexpected separator chars");
1299
1300 // Scan the format string to determine the length of the actual
1301 // boot classpath, and handle platform dependencies as well.
1302 int formatted_path_len = 0;
1303 const char* p;
1304 for (p = format_string; *p != 0; ++p) {
1305 if (*p == '%') formatted_path_len += home_len - 1;
1306 ++formatted_path_len;
1307 }
1308
1309 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal);
1310
1311 // Create boot classpath from format, substituting separator chars and
1312 // java home directory.
1313 char* q = formatted_path;
1314 for (p = format_string; *p != 0; ++p) {
1315 switch (*p) {
1316 case '%':
1317 strcpy(q, home);
1318 q += home_len;
1319 break;
1320 case '/':
1321 *q++ = fileSep;
1322 break;
1323 case ':':
1324 *q++ = pathSep;
1325 break;
1326 default:
1327 *q++ = *p;
1328 }
1329 }
1330 *q = '\0';
1331
1332 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched");
1333 return formatted_path;
1334 }
1335
1336 // This function is a proxy to fopen, it tries to add a non standard flag ('e' or 'N')
1337 // that ensures automatic closing of the file on exec. If it can not find support in
1338 // the underlying c library, it will make an extra system call (fcntl) to ensure automatic
1339 // closing of the file on exec.
1340 FILE* os::fopen(const char* path, const char* mode) {
1341 char modified_mode[20];
1342 assert(strlen(mode) + 1 < sizeof(modified_mode), "mode chars plus one extra must fit in buffer");
1343 sprintf(modified_mode, "%s" LINUX_ONLY("e") BSD_ONLY("e") WINDOWS_ONLY("N"), mode);
1344 FILE* file = ::fopen(path, modified_mode);
1345
1346 #if !(defined LINUX || defined BSD || defined _WINDOWS)
1347 // assume fcntl FD_CLOEXEC support as a backup solution when 'e' or 'N'
1348 // is not supported as mode in fopen
1349 if (file != NULL) {
1350 int fd = fileno(file);
1351 if (fd != -1) {
1352 int fd_flags = fcntl(fd, F_GETFD);
1353 if (fd_flags != -1) {
1354 fcntl(fd, F_SETFD, fd_flags | FD_CLOEXEC);
1355 }
1356 }
1357 }
1358 #endif
1359
1360 return file;
1361 }
1362
1363 ssize_t os::read(int fd, void *buf, unsigned int nBytes) {
1364 return ::read(fd, buf, nBytes);
1365 }
1366
1367 bool os::set_boot_path(char fileSep, char pathSep) {
1368 const char* home = Arguments::get_java_home();
1369 int home_len = (int)strlen(home);
1370
1371 struct stat st;
1372
1373 // modular image if "modules" jimage exists
1374 char* jimage = format_boot_path("%/lib/" MODULES_IMAGE_NAME, home, home_len, fileSep, pathSep);
1375 if (jimage == NULL) return false;
1376 bool has_jimage = (os::stat(jimage, &st) == 0);
1377 if (has_jimage) {
1378 Arguments::set_sysclasspath(jimage, true);
1379 FREE_C_HEAP_ARRAY(char, jimage);
1380 return true;
1381 }
1382 FREE_C_HEAP_ARRAY(char, jimage);
1383
1384 // check if developer build with exploded modules
1385 char* base_classes = format_boot_path("%/modules/" JAVA_BASE_NAME, home, home_len, fileSep, pathSep);
1386 if (base_classes == NULL) return false;
1387 if (os::stat(base_classes, &st) == 0) {
1388 Arguments::set_sysclasspath(base_classes, false);
1389 FREE_C_HEAP_ARRAY(char, base_classes);
1390 return true;
1391 }
1392 FREE_C_HEAP_ARRAY(char, base_classes);
1393
1394 return false;
1395 }
1396
1397 bool os::file_exists(const char* filename) {
1398 struct stat statbuf;
1399 if (filename == NULL || strlen(filename) == 0) {
1400 return false;
1401 }
1402 return os::stat(filename, &statbuf) == 0;
1403 }
1404
1405 // Splits a path, based on its separator, the number of
1406 // elements is returned back in "elements".
1407 // file_name_length is used as a modifier for each path's
1408 // length when compared to JVM_MAXPATHLEN. So if you know
1409 // each returned path will have something appended when
1410 // in use, you can pass the length of that in
1411 // file_name_length, to ensure we detect if any path
1412 // exceeds the maximum path length once prepended onto
1413 // the sub-path/file name.
1414 // It is the callers responsibility to:
1415 // a> check the value of "elements", which may be 0.
1416 // b> ignore any empty path elements
1417 // c> free up the data.
1418 char** os::split_path(const char* path, size_t* elements, size_t file_name_length) {
1419 *elements = (size_t)0;
1420 if (path == NULL || strlen(path) == 0 || file_name_length == (size_t)NULL) {
1421 return NULL;
1422 }
1423 const char psepchar = *os::path_separator();
1424 char* inpath = NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal);
1425 strcpy(inpath, path);
1426 size_t count = 1;
1427 char* p = strchr(inpath, psepchar);
1428 // Get a count of elements to allocate memory
1429 while (p != NULL) {
1430 count++;
1431 p++;
1432 p = strchr(p, psepchar);
1433 }
1434
1435 char** opath = NEW_C_HEAP_ARRAY(char*, count, mtInternal);
1436
1437 // do the actual splitting
1438 p = inpath;
1439 for (size_t i = 0 ; i < count ; i++) {
1440 size_t len = strcspn(p, os::path_separator());
1441 if (len + file_name_length > JVM_MAXPATHLEN) {
1442 // release allocated storage before exiting the vm
1443 free_array_of_char_arrays(opath, i++);
1444 vm_exit_during_initialization("The VM tried to use a path that exceeds the maximum path length for "
1445 "this system. Review path-containing parameters and properties, such as "
1446 "sun.boot.library.path, to identify potential sources for this path.");
1447 }
1448 // allocate the string and add terminator storage
1449 char* s = NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
1450 strncpy(s, p, len);
1451 s[len] = '\0';
1452 opath[i] = s;
1453 p += len + 1;
1454 }
1455 FREE_C_HEAP_ARRAY(char, inpath);
1456 *elements = count;
1457 return opath;
1458 }
1459
1460 // Returns true if the current stack pointer is above the stack shadow
1461 // pages, false otherwise.
1462 bool os::stack_shadow_pages_available(Thread *thread, const methodHandle& method, address sp) {
1463 if (!thread->is_Java_thread()) return false;
1464 // Check if we have StackShadowPages above the yellow zone. This parameter
1465 // is dependent on the depth of the maximum VM call stack possible from
1466 // the handler for stack overflow. 'instanceof' in the stack overflow
1467 // handler or a println uses at least 8k stack of VM and native code
1468 // respectively.
1469 const int framesize_in_bytes =
1470 Interpreter::size_top_interpreter_activation(method()) * wordSize;
1471
1472 address limit = JavaThread::cast(thread)->stack_end() +
1473 (StackOverflow::stack_guard_zone_size() + StackOverflow::stack_shadow_zone_size());
1474
1475 return sp > (limit + framesize_in_bytes);
1476 }
1477
1478 size_t os::page_size_for_region(size_t region_size, size_t min_pages, bool must_be_aligned) {
1479 assert(min_pages > 0, "sanity");
1480 if (UseLargePages) {
1481 const size_t max_page_size = region_size / min_pages;
1482
1483 for (size_t page_size = page_sizes().largest(); page_size != 0;
1484 page_size = page_sizes().next_smaller(page_size)) {
1485 if (page_size <= max_page_size) {
1486 if (!must_be_aligned || is_aligned(region_size, page_size)) {
1487 return page_size;
1488 }
1489 }
1490 }
1491 }
1492
1493 return vm_page_size();
1494 }
1495
1496 size_t os::page_size_for_region_aligned(size_t region_size, size_t min_pages) {
1497 return page_size_for_region(region_size, min_pages, true);
1498 }
1499
1500 size_t os::page_size_for_region_unaligned(size_t region_size, size_t min_pages) {
1501 return page_size_for_region(region_size, min_pages, false);
1502 }
1503
1504 static const char* errno_to_string (int e, bool short_text) {
1505 #define ALL_SHARED_ENUMS(X) \
1506 X(E2BIG, "Argument list too long") \
1507 X(EACCES, "Permission denied") \
1508 X(EADDRINUSE, "Address in use") \
1509 X(EADDRNOTAVAIL, "Address not available") \
1510 X(EAFNOSUPPORT, "Address family not supported") \
1511 X(EAGAIN, "Resource unavailable, try again") \
1512 X(EALREADY, "Connection already in progress") \
1513 X(EBADF, "Bad file descriptor") \
1514 X(EBADMSG, "Bad message") \
1515 X(EBUSY, "Device or resource busy") \
1516 X(ECANCELED, "Operation canceled") \
1517 X(ECHILD, "No child processes") \
1518 X(ECONNABORTED, "Connection aborted") \
1519 X(ECONNREFUSED, "Connection refused") \
1520 X(ECONNRESET, "Connection reset") \
1521 X(EDEADLK, "Resource deadlock would occur") \
1522 X(EDESTADDRREQ, "Destination address required") \
1523 X(EDOM, "Mathematics argument out of domain of function") \
1524 X(EEXIST, "File exists") \
1525 X(EFAULT, "Bad address") \
1526 X(EFBIG, "File too large") \
1527 X(EHOSTUNREACH, "Host is unreachable") \
1528 X(EIDRM, "Identifier removed") \
1529 X(EILSEQ, "Illegal byte sequence") \
1530 X(EINPROGRESS, "Operation in progress") \
1531 X(EINTR, "Interrupted function") \
1532 X(EINVAL, "Invalid argument") \
1533 X(EIO, "I/O error") \
1534 X(EISCONN, "Socket is connected") \
1535 X(EISDIR, "Is a directory") \
1536 X(ELOOP, "Too many levels of symbolic links") \
1537 X(EMFILE, "Too many open files") \
1538 X(EMLINK, "Too many links") \
1539 X(EMSGSIZE, "Message too large") \
1540 X(ENAMETOOLONG, "Filename too long") \
1541 X(ENETDOWN, "Network is down") \
1542 X(ENETRESET, "Connection aborted by network") \
1543 X(ENETUNREACH, "Network unreachable") \
1544 X(ENFILE, "Too many files open in system") \
1545 X(ENOBUFS, "No buffer space available") \
1546 X(ENODATA, "No message is available on the STREAM head read queue") \
1547 X(ENODEV, "No such device") \
1548 X(ENOENT, "No such file or directory") \
1549 X(ENOEXEC, "Executable file format error") \
1550 X(ENOLCK, "No locks available") \
1551 X(ENOLINK, "Reserved") \
1552 X(ENOMEM, "Not enough space") \
1553 X(ENOMSG, "No message of the desired type") \
1554 X(ENOPROTOOPT, "Protocol not available") \
1555 X(ENOSPC, "No space left on device") \
1556 X(ENOSR, "No STREAM resources") \
1557 X(ENOSTR, "Not a STREAM") \
1558 X(ENOSYS, "Function not supported") \
1559 X(ENOTCONN, "The socket is not connected") \
1560 X(ENOTDIR, "Not a directory") \
1561 X(ENOTEMPTY, "Directory not empty") \
1562 X(ENOTSOCK, "Not a socket") \
1563 X(ENOTSUP, "Not supported") \
1564 X(ENOTTY, "Inappropriate I/O control operation") \
1565 X(ENXIO, "No such device or address") \
1566 X(EOPNOTSUPP, "Operation not supported on socket") \
1567 X(EOVERFLOW, "Value too large to be stored in data type") \
1568 X(EPERM, "Operation not permitted") \
1569 X(EPIPE, "Broken pipe") \
1570 X(EPROTO, "Protocol error") \
1571 X(EPROTONOSUPPORT, "Protocol not supported") \
1572 X(EPROTOTYPE, "Protocol wrong type for socket") \
1573 X(ERANGE, "Result too large") \
1574 X(EROFS, "Read-only file system") \
1575 X(ESPIPE, "Invalid seek") \
1576 X(ESRCH, "No such process") \
1577 X(ETIME, "Stream ioctl() timeout") \
1578 X(ETIMEDOUT, "Connection timed out") \
1579 X(ETXTBSY, "Text file busy") \
1580 X(EWOULDBLOCK, "Operation would block") \
1581 X(EXDEV, "Cross-device link")
1582
1583 #define DEFINE_ENTRY(e, text) { e, #e, text },
1584
1585 static const struct {
1586 int v;
1587 const char* short_text;
1588 const char* long_text;
1589 } table [] = {
1590
1591 ALL_SHARED_ENUMS(DEFINE_ENTRY)
1592
1593 // The following enums are not defined on all platforms.
1594 #ifdef ESTALE
1595 DEFINE_ENTRY(ESTALE, "Reserved")
1596 #endif
1597 #ifdef EDQUOT
1598 DEFINE_ENTRY(EDQUOT, "Reserved")
1599 #endif
1600 #ifdef EMULTIHOP
1601 DEFINE_ENTRY(EMULTIHOP, "Reserved")
1602 #endif
1603
1604 // End marker.
1605 { -1, "Unknown errno", "Unknown error" }
1606
1607 };
1608
1609 #undef DEFINE_ENTRY
1610 #undef ALL_FLAGS
1611
1612 int i = 0;
1613 while (table[i].v != -1 && table[i].v != e) {
1614 i ++;
1615 }
1616
1617 return short_text ? table[i].short_text : table[i].long_text;
1618
1619 }
1620
1621 const char* os::strerror(int e) {
1622 return errno_to_string(e, false);
1623 }
1624
1625 const char* os::errno_name(int e) {
1626 return errno_to_string(e, true);
1627 }
1628
1629 #define trace_page_size_params(size) byte_size_in_exact_unit(size), exact_unit_for_byte_size(size)
1630
1631 void os::trace_page_sizes(const char* str,
1632 const size_t region_min_size,
1633 const size_t region_max_size,
1634 const size_t page_size,
1635 const char* base,
1636 const size_t size) {
1637
1638 log_info(pagesize)("%s: "
1639 " min=" SIZE_FORMAT "%s"
1640 " max=" SIZE_FORMAT "%s"
1641 " base=" PTR_FORMAT
1642 " page_size=" SIZE_FORMAT "%s"
1643 " size=" SIZE_FORMAT "%s",
1644 str,
1645 trace_page_size_params(region_min_size),
1646 trace_page_size_params(region_max_size),
1647 p2i(base),
1648 trace_page_size_params(page_size),
1649 trace_page_size_params(size));
1650 }
1651
1652 void os::trace_page_sizes_for_requested_size(const char* str,
1653 const size_t requested_size,
1654 const size_t page_size,
1655 const size_t alignment,
1656 const char* base,
1657 const size_t size) {
1658
1659 log_info(pagesize)("%s:"
1660 " req_size=" SIZE_FORMAT "%s"
1661 " base=" PTR_FORMAT
1662 " page_size=" SIZE_FORMAT "%s"
1663 " alignment=" SIZE_FORMAT "%s"
1664 " size=" SIZE_FORMAT "%s",
1665 str,
1666 trace_page_size_params(requested_size),
1667 p2i(base),
1668 trace_page_size_params(page_size),
1669 trace_page_size_params(alignment),
1670 trace_page_size_params(size));
1671 }
1672
1673
1674 // This is the working definition of a server class machine:
1675 // >= 2 physical CPU's and >=2GB of memory, with some fuzz
1676 // because the graphics memory (?) sometimes masks physical memory.
1677 // If you want to change the definition of a server class machine
1678 // on some OS or platform, e.g., >=4GB on Windows platforms,
1679 // then you'll have to parameterize this method based on that state,
1680 // as was done for logical processors here, or replicate and
1681 // specialize this method for each platform. (Or fix os to have
1682 // some inheritance structure and use subclassing. Sigh.)
1683 // If you want some platform to always or never behave as a server
1684 // class machine, change the setting of AlwaysActAsServerClassMachine
1685 // and NeverActAsServerClassMachine in globals*.hpp.
1686 bool os::is_server_class_machine() {
1687 // First check for the early returns
1688 if (NeverActAsServerClassMachine) {
1689 return false;
1690 }
1691 if (AlwaysActAsServerClassMachine) {
1692 return true;
1693 }
1694 // Then actually look at the machine
1695 bool result = false;
1696 const unsigned int server_processors = 2;
1697 const julong server_memory = 2UL * G;
1698 // We seem not to get our full complement of memory.
1699 // We allow some part (1/8?) of the memory to be "missing",
1700 // based on the sizes of DIMMs, and maybe graphics cards.
1701 const julong missing_memory = 256UL * M;
1702
1703 /* Is this a server class machine? */
1704 if ((os::active_processor_count() >= (int)server_processors) &&
1705 (os::physical_memory() >= (server_memory - missing_memory))) {
1706 const unsigned int logical_processors =
1707 VM_Version::logical_processors_per_package();
1708 if (logical_processors > 1) {
1709 const unsigned int physical_packages =
1710 os::active_processor_count() / logical_processors;
1711 if (physical_packages >= server_processors) {
1712 result = true;
1713 }
1714 } else {
1715 result = true;
1716 }
1717 }
1718 return result;
1719 }
1720
1721 void os::initialize_initial_active_processor_count() {
1722 assert(_initial_active_processor_count == 0, "Initial active processor count already set.");
1723 _initial_active_processor_count = active_processor_count();
1724 log_debug(os)("Initial active processor count set to %d" , _initial_active_processor_count);
1725 }
1726
1727 void os::SuspendedThreadTask::run() {
1728 internal_do_task();
1729 _done = true;
1730 }
1731
1732 bool os::create_stack_guard_pages(char* addr, size_t bytes) {
1733 return os::pd_create_stack_guard_pages(addr, bytes);
1734 }
1735
1736 char* os::reserve_memory(size_t bytes, bool executable, MEMFLAGS flags) {
1737 char* result = pd_reserve_memory(bytes, executable);
1738 if (result != NULL) {
1739 MemTracker::record_virtual_memory_reserve(result, bytes, CALLER_PC);
1740 if (flags != mtOther) {
1741 MemTracker::record_virtual_memory_type(result, flags);
1742 }
1743 }
1744
1745 return result;
1746 }
1747
1748 char* os::attempt_reserve_memory_at(char* addr, size_t bytes, bool executable) {
1749 char* result = pd_attempt_reserve_memory_at(addr, bytes, executable);
1750 if (result != NULL) {
1751 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1752 } else {
1753 log_debug(os)("Attempt to reserve memory at " INTPTR_FORMAT " for "
1754 SIZE_FORMAT " bytes failed, errno %d", p2i(addr), bytes, get_last_error());
1755 }
1756 return result;
1757 }
1758
1759 bool os::commit_memory(char* addr, size_t bytes, bool executable) {
1760 bool res = pd_commit_memory(addr, bytes, executable);
1761 if (res) {
1762 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1763 }
1764 return res;
1765 }
1766
1767 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint,
1768 bool executable) {
1769 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable);
1770 if (res) {
1771 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1772 }
1773 return res;
1774 }
1775
1776 void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable,
1777 const char* mesg) {
1778 pd_commit_memory_or_exit(addr, bytes, executable, mesg);
1779 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1780 }
1781
1782 void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint,
1783 bool executable, const char* mesg) {
1784 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg);
1785 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1786 }
1787
1788 bool os::uncommit_memory(char* addr, size_t bytes, bool executable) {
1789 bool res;
1790 if (MemTracker::enabled()) {
1791 Tracker tkr(Tracker::uncommit);
1792 res = pd_uncommit_memory(addr, bytes, executable);
1793 if (res) {
1794 tkr.record((address)addr, bytes);
1795 }
1796 } else {
1797 res = pd_uncommit_memory(addr, bytes, executable);
1798 }
1799 return res;
1800 }
1801
1802 bool os::release_memory(char* addr, size_t bytes) {
1803 bool res;
1804 if (MemTracker::enabled()) {
1805 // Note: Tracker contains a ThreadCritical.
1806 Tracker tkr(Tracker::release);
1807 res = pd_release_memory(addr, bytes);
1808 if (res) {
1809 tkr.record((address)addr, bytes);
1810 }
1811 } else {
1812 res = pd_release_memory(addr, bytes);
1813 }
1814 if (!res) {
1815 log_info(os)("os::release_memory failed (" PTR_FORMAT ", " SIZE_FORMAT ")", p2i(addr), bytes);
1816 }
1817 return res;
1818 }
1819
1820 // Prints all mappings
1821 void os::print_memory_mappings(outputStream* st) {
1822 os::print_memory_mappings(nullptr, (size_t)-1, st);
1823 }
1824
1825 void os::pretouch_memory(void* start, void* end, size_t page_size) {
1826 for (volatile char *p = (char*)start; p < (char*)end; p += page_size) {
1827 // Note: this must be a store, not a load. On many OSes loads from fresh
1828 // memory would be satisfied from a single mapped page containing all zeros.
1829 // We need to store something to each page to get them backed by their own
1830 // memory, which is the effect we want here.
1831 *p = 0;
1832 }
1833 }
1834
1835 char* os::map_memory_to_file(size_t bytes, int file_desc) {
1836 // Could have called pd_reserve_memory() followed by replace_existing_mapping_with_file_mapping(),
1837 // but AIX may use SHM in which case its more trouble to detach the segment and remap memory to the file.
1838 // On all current implementations NULL is interpreted as any available address.
1839 char* result = os::map_memory_to_file(NULL /* addr */, bytes, file_desc);
1840 if (result != NULL) {
1841 MemTracker::record_virtual_memory_reserve_and_commit(result, bytes, CALLER_PC);
1842 }
1843 return result;
1844 }
1845
1846 char* os::attempt_map_memory_to_file_at(char* addr, size_t bytes, int file_desc) {
1847 char* result = pd_attempt_map_memory_to_file_at(addr, bytes, file_desc);
1848 if (result != NULL) {
1849 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC);
1850 }
1851 return result;
1852 }
1853
1854 char* os::map_memory(int fd, const char* file_name, size_t file_offset,
1855 char *addr, size_t bytes, bool read_only,
1856 bool allow_exec, MEMFLAGS flags) {
1857 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec);
1858 if (result != NULL) {
1859 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC, flags);
1860 }
1861 return result;
1862 }
1863
1864 char* os::remap_memory(int fd, const char* file_name, size_t file_offset,
1865 char *addr, size_t bytes, bool read_only,
1866 bool allow_exec) {
1867 return pd_remap_memory(fd, file_name, file_offset, addr, bytes,
1868 read_only, allow_exec);
1869 }
1870
1871 bool os::unmap_memory(char *addr, size_t bytes) {
1872 bool result;
1873 if (MemTracker::enabled()) {
1874 Tracker tkr(Tracker::release);
1875 result = pd_unmap_memory(addr, bytes);
1876 if (result) {
1877 tkr.record((address)addr, bytes);
1878 }
1879 } else {
1880 result = pd_unmap_memory(addr, bytes);
1881 }
1882 return result;
1883 }
1884
1885 void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) {
1886 pd_free_memory(addr, bytes, alignment_hint);
1887 }
1888
1889 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
1890 pd_realign_memory(addr, bytes, alignment_hint);
1891 }
1892
1893 char* os::reserve_memory_special(size_t size, size_t alignment, size_t page_size,
1894 char* addr, bool executable) {
1895
1896 assert(is_aligned(addr, alignment), "Unaligned request address");
1897
1898 char* result = pd_reserve_memory_special(size, alignment, page_size, addr, executable);
1899 if (result != NULL) {
1900 // The memory is committed
1901 MemTracker::record_virtual_memory_reserve_and_commit((address)result, size, CALLER_PC);
1902 }
1903
1904 return result;
1905 }
1906
1907 bool os::release_memory_special(char* addr, size_t bytes) {
1908 bool res;
1909 if (MemTracker::enabled()) {
1910 // Note: Tracker contains a ThreadCritical.
1911 Tracker tkr(Tracker::release);
1912 res = pd_release_memory_special(addr, bytes);
1913 if (res) {
1914 tkr.record((address)addr, bytes);
1915 }
1916 } else {
1917 res = pd_release_memory_special(addr, bytes);
1918 }
1919 return res;
1920 }
1921
1922 #ifndef _WINDOWS
1923 /* try to switch state from state "from" to state "to"
1924 * returns the state set after the method is complete
1925 */
1926 os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from,
1927 os::SuspendResume::State to)
1928 {
1929 os::SuspendResume::State result = Atomic::cmpxchg(&_state, from, to);
1930 if (result == from) {
1931 // success
1932 return to;
1933 }
1934 return result;
1935 }
1936 #endif
1937
1938 // Convenience wrapper around naked_short_sleep to allow for longer sleep
1939 // times. Only for use by non-JavaThreads.
1940 void os::naked_sleep(jlong millis) {
1941 assert(!Thread::current()->is_Java_thread(), "not for use by JavaThreads");
1942 const jlong limit = 999;
1943 while (millis > limit) {
1944 naked_short_sleep(limit);
1945 millis -= limit;
1946 }
1947 naked_short_sleep(millis);
1948 }
1949
1950
1951 ////// Implementation of PageSizes
1952
1953 void os::PageSizes::add(size_t page_size) {
1954 assert(is_power_of_2(page_size), "page_size must be a power of 2: " SIZE_FORMAT_HEX, page_size);
1955 _v |= page_size;
1956 }
1957
1958 bool os::PageSizes::contains(size_t page_size) const {
1959 assert(is_power_of_2(page_size), "page_size must be a power of 2: " SIZE_FORMAT_HEX, page_size);
1960 return (_v & page_size) != 0;
1961 }
1962
1963 size_t os::PageSizes::next_smaller(size_t page_size) const {
1964 assert(is_power_of_2(page_size), "page_size must be a power of 2: " SIZE_FORMAT_HEX, page_size);
1965 size_t v2 = _v & (page_size - 1);
1966 if (v2 == 0) {
1967 return 0;
1968 }
1969 return round_down_power_of_2(v2);
1970 }
1971
1972 size_t os::PageSizes::next_larger(size_t page_size) const {
1973 assert(is_power_of_2(page_size), "page_size must be a power of 2: " SIZE_FORMAT_HEX, page_size);
1974 if (page_size == max_power_of_2<size_t>()) { // Shift by 32/64 would be UB
1975 return 0;
1976 }
1977 // Remove current and smaller page sizes
1978 size_t v2 = _v & ~(page_size + (page_size - 1));
1979 if (v2 == 0) {
1980 return 0;
1981 }
1982 return (size_t)1 << count_trailing_zeros(v2);
1983 }
1984
1985 size_t os::PageSizes::largest() const {
1986 const size_t max = max_power_of_2<size_t>();
1987 if (contains(max)) {
1988 return max;
1989 }
1990 return next_smaller(max);
1991 }
1992
1993 size_t os::PageSizes::smallest() const {
1994 // Strictly speaking the set should not contain sizes < os::vm_page_size().
1995 // But this is not enforced.
1996 return next_larger(1);
1997 }
1998
1999 void os::PageSizes::print_on(outputStream* st) const {
2000 bool first = true;
2001 for (size_t sz = smallest(); sz != 0; sz = next_larger(sz)) {
2002 if (first) {
2003 first = false;
2004 } else {
2005 st->print_raw(", ");
2006 }
2007 if (sz < M) {
2008 st->print(SIZE_FORMAT "k", sz / K);
2009 } else if (sz < G) {
2010 st->print(SIZE_FORMAT "M", sz / M);
2011 } else {
2012 st->print(SIZE_FORMAT "G", sz / G);
2013 }
2014 }
2015 if (first) {
2016 st->print("empty");
2017 }
2018 }