1 /*
2 * Copyright (c) 1997, 2019, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "jvm.h"
27 #include "classfile/classLoader.hpp"
28 #include "classfile/javaClasses.hpp"
29 #include "classfile/moduleEntry.hpp"
30 #include "classfile/systemDictionary.hpp"
31 #include "classfile/vmSymbols.hpp"
32 #include "code/codeCache.hpp"
33 #include "code/icBuffer.hpp"
34 #include "code/vtableStubs.hpp"
35 #include "gc/shared/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/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/mutexLocker.hpp"
55 #include "runtime/os.inline.hpp"
56 #include "runtime/sharedRuntime.hpp"
57 #include "runtime/stubRoutines.hpp"
58 #include "runtime/thread.inline.hpp"
59 #include "runtime/threadSMR.hpp"
60 #include "runtime/vm_version.hpp"
61 #include "services/attachListener.hpp"
62 #include "services/mallocTracker.hpp"
63 #include "services/memTracker.hpp"
64 #include "services/nmtCommon.hpp"
65 #include "services/threadService.hpp"
66 #include "utilities/align.hpp"
67 #include "utilities/defaultStream.hpp"
68 #include "utilities/events.hpp"
69
70 # include <signal.h>
71 # include <errno.h>
72
73 OSThread* os::_starting_thread = NULL;
74 address os::_polling_page = NULL;
75 volatile unsigned int os::_rand_seed = 1;
76 int os::_processor_count = 0;
77 int os::_initial_active_processor_count = 0;
78 size_t os::_page_sizes[os::page_sizes_max];
79
80 #ifndef PRODUCT
81 julong os::num_mallocs = 0; // # of calls to malloc/realloc
82 julong os::alloc_bytes = 0; // # of bytes allocated
83 julong os::num_frees = 0; // # of calls to free
84 julong os::free_bytes = 0; // # of bytes freed
85 #endif
86
87 static size_t cur_malloc_words = 0; // current size for MallocMaxTestWords
88
DEBUG_ONLY(bool os::_mutex_init_done=false;)89 DEBUG_ONLY(bool os::_mutex_init_done = false;)
90
91 static time_t get_timezone(const struct tm* time_struct) {
92 #if defined(_ALLBSD_SOURCE)
93 return time_struct->tm_gmtoff;
94 #elif defined(_WINDOWS)
95 long zone;
96 _get_timezone(&zone);
97 return static_cast<time_t>(zone);
98 #else
99 return timezone;
100 #endif
101 }
102
snprintf(char * buf,size_t len,const char * fmt,...)103 int os::snprintf(char* buf, size_t len, const char* fmt, ...) {
104 va_list args;
105 va_start(args, fmt);
106 int result = os::vsnprintf(buf, len, fmt, args);
107 va_end(args);
108 return result;
109 }
110
111 // Fill in buffer with current local time as an ISO-8601 string.
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.
iso8601_time(char * buffer,size_t buffer_length,bool utc)119 char* os::iso8601_time(char* buffer, size_t buffer_length, bool utc) {
120 // Output will be of the form "YYYY-MM-DDThh:mm:ss.mmm+zzzz\0"
121 // 1 2
122 // 12345678901234567890123456789
123 // format string: "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d"
124 static const size_t needed_buffer = 29;
125
126 // Sanity check the arguments
127 if (buffer == NULL) {
128 assert(false, "NULL buffer");
129 return NULL;
130 }
131 if (buffer_length < needed_buffer) {
132 assert(false, "buffer_length too small");
133 return NULL;
134 }
135 // Get the current time
136 jlong milliseconds_since_19700101 = javaTimeMillis();
137 const int milliseconds_per_microsecond = 1000;
138 const time_t seconds_since_19700101 =
139 milliseconds_since_19700101 / milliseconds_per_microsecond;
140 const int milliseconds_after_second =
141 milliseconds_since_19700101 % milliseconds_per_microsecond;
142 // Convert the time value to a tm and timezone variable
143 struct tm time_struct;
144 if (utc) {
145 if (gmtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
146 assert(false, "Failed gmtime_pd");
147 return NULL;
148 }
149 } else {
150 if (localtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
151 assert(false, "Failed localtime_pd");
152 return NULL;
153 }
154 }
155 const time_t zone = get_timezone(&time_struct);
156
157 // If daylight savings time is in effect,
158 // we are 1 hour East of our time zone
159 const time_t seconds_per_minute = 60;
160 const time_t minutes_per_hour = 60;
161 const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour;
162 time_t UTC_to_local = zone;
163 if (time_struct.tm_isdst > 0) {
164 UTC_to_local = UTC_to_local - seconds_per_hour;
165 }
166
167 // No offset when dealing with UTC
168 if (utc) {
169 UTC_to_local = 0;
170 }
171
172 // Compute the time zone offset.
173 // localtime_pd() sets timezone to the difference (in seconds)
174 // between UTC and and local time.
175 // ISO 8601 says we need the difference between local time and UTC,
176 // we change the sign of the localtime_pd() result.
177 const time_t local_to_UTC = -(UTC_to_local);
178 // Then we have to figure out if if we are ahead (+) or behind (-) UTC.
179 char sign_local_to_UTC = '+';
180 time_t abs_local_to_UTC = local_to_UTC;
181 if (local_to_UTC < 0) {
182 sign_local_to_UTC = '-';
183 abs_local_to_UTC = -(abs_local_to_UTC);
184 }
185 // Convert time zone offset seconds to hours and minutes.
186 const time_t zone_hours = (abs_local_to_UTC / seconds_per_hour);
187 const time_t zone_min =
188 ((abs_local_to_UTC % seconds_per_hour) / seconds_per_minute);
189
190 // Print an ISO 8601 date and time stamp into the buffer
191 const int year = 1900 + time_struct.tm_year;
192 const int month = 1 + time_struct.tm_mon;
193 const int printed = jio_snprintf(buffer, buffer_length,
194 "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d",
195 year,
196 month,
197 time_struct.tm_mday,
198 time_struct.tm_hour,
199 time_struct.tm_min,
200 time_struct.tm_sec,
201 milliseconds_after_second,
202 sign_local_to_UTC,
203 zone_hours,
204 zone_min);
205 if (printed == 0) {
206 assert(false, "Failed jio_printf");
207 return NULL;
208 }
209 return buffer;
210 }
211
set_priority(Thread * thread,ThreadPriority p)212 OSReturn os::set_priority(Thread* thread, ThreadPriority p) {
213 debug_only(Thread::check_for_dangling_thread_pointer(thread);)
214
215 if ((p >= MinPriority && p <= MaxPriority) ||
216 (p == CriticalPriority && thread->is_ConcurrentGC_thread())) {
217 int priority = java_to_os_priority[p];
218 return set_native_priority(thread, priority);
219 } else {
220 assert(false, "Should not happen");
221 return OS_ERR;
222 }
223 }
224
225 // The mapping from OS priority back to Java priority may be inexact because
226 // Java priorities can map M:1 with native priorities. If you want the definite
227 // Java priority then use JavaThread::java_priority()
get_priority(const Thread * const thread,ThreadPriority & priority)228 OSReturn os::get_priority(const Thread* const thread, ThreadPriority& priority) {
229 int p;
230 int os_prio;
231 OSReturn ret = get_native_priority(thread, &os_prio);
232 if (ret != OS_OK) return ret;
233
234 if (java_to_os_priority[MaxPriority] > java_to_os_priority[MinPriority]) {
235 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] > os_prio; p--) ;
236 } else {
237 // niceness values are in reverse order
238 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] < os_prio; p--) ;
239 }
240 priority = (ThreadPriority)p;
241 return OS_OK;
242 }
243
dll_build_name(char * buffer,size_t size,const char * fname)244 bool os::dll_build_name(char* buffer, size_t size, const char* fname) {
245 int n = jio_snprintf(buffer, size, "%s%s%s", JNI_LIB_PREFIX, fname, JNI_LIB_SUFFIX);
246 return (n != -1);
247 }
248
249 #if !defined(LINUX) && !defined(_WINDOWS)
committed_in_range(address start,size_t size,address & committed_start,size_t & committed_size)250 bool os::committed_in_range(address start, size_t size, address& committed_start, size_t& committed_size) {
251 committed_start = start;
252 committed_size = size;
253 return true;
254 }
255 #endif
256
257 // Helper for dll_locate_lib.
258 // Pass buffer and printbuffer as we already printed the path to buffer
259 // when we called get_current_directory. This way we avoid another buffer
260 // of size MAX_PATH.
conc_path_file_and_check(char * buffer,char * printbuffer,size_t printbuflen,const char * pname,char lastchar,const char * fname)261 static bool conc_path_file_and_check(char *buffer, char *printbuffer, size_t printbuflen,
262 const char* pname, char lastchar, const char* fname) {
263
264 // Concatenate path and file name, but don't print double path separators.
265 const char *filesep = (WINDOWS_ONLY(lastchar == ':' ||) lastchar == os::file_separator()[0]) ?
266 "" : os::file_separator();
267 int ret = jio_snprintf(printbuffer, printbuflen, "%s%s%s", pname, filesep, fname);
268 // Check whether file exists.
269 if (ret != -1) {
270 struct stat statbuf;
271 return os::stat(buffer, &statbuf) == 0;
272 }
273 return false;
274 }
275
276 // Frees all memory allocated on the heap for the
277 // supplied array of arrays of chars (a), where n
278 // is the number of elements in the array.
free_array_of_char_arrays(char ** a,size_t n)279 static void free_array_of_char_arrays(char** a, size_t n) {
280 while (n > 0) {
281 n--;
282 if (a[n] != NULL) {
283 FREE_C_HEAP_ARRAY(char, a[n]);
284 }
285 }
286 FREE_C_HEAP_ARRAY(char*, a);
287 }
288
dll_locate_lib(char * buffer,size_t buflen,const char * pname,const char * fname)289 bool os::dll_locate_lib(char *buffer, size_t buflen,
290 const char* pname, const char* fname) {
291 bool retval = false;
292
293 size_t fullfnamelen = strlen(JNI_LIB_PREFIX) + strlen(fname) + strlen(JNI_LIB_SUFFIX);
294 char* fullfname = NEW_C_HEAP_ARRAY(char, fullfnamelen + 1, mtInternal);
295 if (dll_build_name(fullfname, fullfnamelen + 1, fname)) {
296 const size_t pnamelen = pname ? strlen(pname) : 0;
297
298 if (pnamelen == 0) {
299 // If no path given, use current working directory.
300 const char* p = get_current_directory(buffer, buflen);
301 if (p != NULL) {
302 const size_t plen = strlen(buffer);
303 const char lastchar = buffer[plen - 1];
304 retval = conc_path_file_and_check(buffer, &buffer[plen], buflen - plen,
305 "", lastchar, fullfname);
306 }
307 } else if (strchr(pname, *os::path_separator()) != NULL) {
308 // A list of paths. Search for the path that contains the library.
309 size_t n;
310 char** pelements = split_path(pname, &n, fullfnamelen);
311 if (pelements != NULL) {
312 for (size_t i = 0; i < n; i++) {
313 char* path = pelements[i];
314 // Really shouldn't be NULL, but check can't hurt.
315 size_t plen = (path == NULL) ? 0 : strlen(path);
316 if (plen == 0) {
317 continue; // Skip the empty path values.
318 }
319 const char lastchar = path[plen - 1];
320 retval = conc_path_file_and_check(buffer, buffer, buflen, path, lastchar, fullfname);
321 if (retval) break;
322 }
323 // Release the storage allocated by split_path.
324 free_array_of_char_arrays(pelements, n);
325 }
326 } else {
327 // A definite path.
328 const char lastchar = pname[pnamelen-1];
329 retval = conc_path_file_and_check(buffer, buffer, buflen, pname, lastchar, fullfname);
330 }
331 }
332
333 FREE_C_HEAP_ARRAY(char*, fullfname);
334 return retval;
335 }
336
337 // --------------------- sun.misc.Signal (optional) ---------------------
338
339
340 // SIGBREAK is sent by the keyboard to query the VM state
341 #ifndef SIGBREAK
342 #define SIGBREAK SIGQUIT
343 #endif
344
345 // sigexitnum_pd is a platform-specific special signal used for terminating the Signal thread.
346
347
signal_thread_entry(JavaThread * thread,TRAPS)348 static void signal_thread_entry(JavaThread* thread, TRAPS) {
349 os::set_priority(thread, NearMaxPriority);
350 while (true) {
351 int sig;
352 {
353 // FIXME : Currently we have not decided what should be the status
354 // for this java thread blocked here. Once we decide about
355 // that we should fix this.
356 sig = os::signal_wait();
357 }
358 if (sig == os::sigexitnum_pd()) {
359 // Terminate the signal thread
360 return;
361 }
362
363 switch (sig) {
364 case SIGBREAK: {
365 #if INCLUDE_SERVICES
366 // Check if the signal is a trigger to start the Attach Listener - in that
367 // case don't print stack traces.
368 if (!DisableAttachMechanism) {
369 // Attempt to transit state to AL_INITIALIZING.
370 AttachListenerState cur_state = AttachListener::transit_state(AL_INITIALIZING, AL_NOT_INITIALIZED);
371 if (cur_state == AL_INITIALIZING) {
372 // Attach Listener has been started to initialize. Ignore this signal.
373 continue;
374 } else if (cur_state == AL_NOT_INITIALIZED) {
375 // Start to initialize.
376 if (AttachListener::is_init_trigger()) {
377 // Attach Listener has been initialized.
378 // Accept subsequent request.
379 continue;
380 } else {
381 // Attach Listener could not be started.
382 // So we need to transit the state to AL_NOT_INITIALIZED.
383 AttachListener::set_state(AL_NOT_INITIALIZED);
384 }
385 } else if (AttachListener::check_socket_file()) {
386 // Attach Listener has been started, but unix domain socket file
387 // does not exist. So restart Attach Listener.
388 continue;
389 }
390 }
391 #endif
392 // Print stack traces
393 // Any SIGBREAK operations added here should make sure to flush
394 // the output stream (e.g. tty->flush()) after output. See 4803766.
395 // Each module also prints an extra carriage return after its output.
396 VM_PrintThreads op;
397 VMThread::execute(&op);
398 VM_PrintJNI jni_op;
399 VMThread::execute(&jni_op);
400 VM_FindDeadlocks op1(tty);
401 VMThread::execute(&op1);
402 Universe::print_heap_at_SIGBREAK();
403 if (PrintClassHistogram) {
404 VM_GC_HeapInspection op1(tty, true /* force full GC before heap inspection */);
405 VMThread::execute(&op1);
406 }
407 if (JvmtiExport::should_post_data_dump()) {
408 JvmtiExport::post_data_dump();
409 }
410 break;
411 }
412 default: {
413 // Dispatch the signal to java
414 HandleMark hm(THREAD);
415 Klass* klass = SystemDictionary::resolve_or_null(vmSymbols::jdk_internal_misc_Signal(), THREAD);
416 if (klass != NULL) {
417 JavaValue result(T_VOID);
418 JavaCallArguments args;
419 args.push_int(sig);
420 JavaCalls::call_static(
421 &result,
422 klass,
423 vmSymbols::dispatch_name(),
424 vmSymbols::int_void_signature(),
425 &args,
426 THREAD
427 );
428 }
429 if (HAS_PENDING_EXCEPTION) {
430 // tty is initialized early so we don't expect it to be null, but
431 // if it is we can't risk doing an initialization that might
432 // trigger additional out-of-memory conditions
433 if (tty != NULL) {
434 char klass_name[256];
435 char tmp_sig_name[16];
436 const char* sig_name = "UNKNOWN";
437 InstanceKlass::cast(PENDING_EXCEPTION->klass())->
438 name()->as_klass_external_name(klass_name, 256);
439 if (os::exception_name(sig, tmp_sig_name, 16) != NULL)
440 sig_name = tmp_sig_name;
441 warning("Exception %s occurred dispatching signal %s to handler"
442 "- the VM may need to be forcibly terminated",
443 klass_name, sig_name );
444 }
445 CLEAR_PENDING_EXCEPTION;
446 }
447 }
448 }
449 }
450 }
451
init_before_ergo()452 void os::init_before_ergo() {
453 initialize_initial_active_processor_count();
454 // We need to initialize large page support here because ergonomics takes some
455 // decisions depending on large page support and the calculated large page size.
456 large_page_init();
457
458 // We need to adapt the configured number of stack protection pages given
459 // in 4K pages to the actual os page size. We must do this before setting
460 // up minimal stack sizes etc. in os::init_2().
461 JavaThread::set_stack_red_zone_size (align_up(StackRedPages * 4 * K, vm_page_size()));
462 JavaThread::set_stack_yellow_zone_size (align_up(StackYellowPages * 4 * K, vm_page_size()));
463 JavaThread::set_stack_reserved_zone_size(align_up(StackReservedPages * 4 * K, vm_page_size()));
464 JavaThread::set_stack_shadow_zone_size (align_up(StackShadowPages * 4 * K, vm_page_size()));
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
initialize_jdk_signal_support(TRAPS)471 void os::initialize_jdk_signal_support(TRAPS) {
472 if (!ReduceSignalUsage) {
473 // Setup JavaThread for processing signals
474 const char thread_name[] = "Signal Dispatcher";
475 Handle string = java_lang_String::create_from_str(thread_name, CHECK);
476
477 // Initialize thread_oop to put it into the system threadGroup
478 Handle thread_group (THREAD, Universe::system_thread_group());
479 Handle thread_oop = JavaCalls::construct_new_instance(SystemDictionary::Thread_klass(),
480 vmSymbols::threadgroup_string_void_signature(),
481 thread_group,
482 string,
483 CHECK);
484
485 Klass* group = SystemDictionary::ThreadGroup_klass();
486 JavaValue result(T_VOID);
487 JavaCalls::call_special(&result,
488 thread_group,
489 group,
490 vmSymbols::add_method_name(),
491 vmSymbols::thread_void_signature(),
492 thread_oop,
493 CHECK);
494
495 { MutexLocker mu(Threads_lock);
496 JavaThread* signal_thread = new JavaThread(&signal_thread_entry);
497
498 // At this point it may be possible that no osthread was created for the
499 // JavaThread due to lack of memory. We would have to throw an exception
500 // in that case. However, since this must work and we do not allow
501 // exceptions anyway, check and abort if this fails.
502 if (signal_thread == NULL || signal_thread->osthread() == NULL) {
503 vm_exit_during_initialization("java.lang.OutOfMemoryError",
504 os::native_thread_creation_failed_msg());
505 }
506
507 java_lang_Thread::set_thread(thread_oop(), signal_thread);
508 java_lang_Thread::set_priority(thread_oop(), NearMaxPriority);
509 java_lang_Thread::set_daemon(thread_oop());
510
511 signal_thread->set_threadObj(thread_oop());
512 Threads::add(signal_thread);
513 Thread::start(signal_thread);
514 }
515 // Handle ^BREAK
516 os::signal(SIGBREAK, os::user_handler());
517 }
518 }
519
520
terminate_signal_thread()521 void os::terminate_signal_thread() {
522 if (!ReduceSignalUsage)
523 signal_notify(sigexitnum_pd());
524 }
525
526
527 // --------------------- loading libraries ---------------------
528
529 typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *);
530 extern struct JavaVM_ main_vm;
531
532 static void* _native_java_library = NULL;
533
native_java_library()534 void* os::native_java_library() {
535 if (_native_java_library == NULL) {
536 char buffer[JVM_MAXPATHLEN];
537 char ebuf[1024];
538
539 // Load java dll
540 if (dll_locate_lib(buffer, sizeof(buffer), Arguments::get_dll_dir(),
541 "java")) {
542 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf));
543 }
544 if (_native_java_library == NULL) {
545 vm_exit_during_initialization("Unable to load native library", ebuf);
546 }
547 }
548 return _native_java_library;
549 }
550
551 /*
552 * Support for finding Agent_On(Un)Load/Attach<_lib_name> if it exists.
553 * If check_lib == true then we are looking for an
554 * Agent_OnLoad_lib_name or Agent_OnAttach_lib_name function to determine if
555 * this library is statically linked into the image.
556 * If check_lib == false then we will look for the appropriate symbol in the
557 * executable if agent_lib->is_static_lib() == true or in the shared library
558 * referenced by 'handle'.
559 */
find_agent_function(AgentLibrary * agent_lib,bool check_lib,const char * syms[],size_t syms_len)560 void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib,
561 const char *syms[], size_t syms_len) {
562 assert(agent_lib != NULL, "sanity check");
563 const char *lib_name;
564 void *handle = agent_lib->os_lib();
565 void *entryName = NULL;
566 char *agent_function_name;
567 size_t i;
568
569 // If checking then use the agent name otherwise test is_static_lib() to
570 // see how to process this lookup
571 lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL);
572 for (i = 0; i < syms_len; i++) {
573 agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path());
574 if (agent_function_name == NULL) {
575 break;
576 }
577 entryName = dll_lookup(handle, agent_function_name);
578 FREE_C_HEAP_ARRAY(char, agent_function_name);
579 if (entryName != NULL) {
580 break;
581 }
582 }
583 return entryName;
584 }
585
586 // See if the passed in agent is statically linked into the VM image.
find_builtin_agent(AgentLibrary * agent_lib,const char * syms[],size_t syms_len)587 bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
588 size_t syms_len) {
589 void *ret;
590 void *proc_handle;
591 void *save_handle;
592
593 assert(agent_lib != NULL, "sanity check");
594 if (agent_lib->name() == NULL) {
595 return false;
596 }
597 proc_handle = get_default_process_handle();
598 // Check for Agent_OnLoad/Attach_lib_name function
599 save_handle = agent_lib->os_lib();
600 // We want to look in this process' symbol table.
601 agent_lib->set_os_lib(proc_handle);
602 ret = find_agent_function(agent_lib, true, syms, syms_len);
603 if (ret != NULL) {
604 // Found an entry point like Agent_OnLoad_lib_name so we have a static agent
605 agent_lib->set_valid();
606 agent_lib->set_static_lib(true);
607 return true;
608 }
609 agent_lib->set_os_lib(save_handle);
610 return false;
611 }
612
613 // --------------------- heap allocation utilities ---------------------
614
strdup(const char * str,MEMFLAGS flags)615 char *os::strdup(const char *str, MEMFLAGS flags) {
616 size_t size = strlen(str);
617 char *dup_str = (char *)malloc(size + 1, flags);
618 if (dup_str == NULL) return NULL;
619 strcpy(dup_str, str);
620 return dup_str;
621 }
622
strdup_check_oom(const char * str,MEMFLAGS flags)623 char* os::strdup_check_oom(const char* str, MEMFLAGS flags) {
624 char* p = os::strdup(str, flags);
625 if (p == NULL) {
626 vm_exit_out_of_memory(strlen(str) + 1, OOM_MALLOC_ERROR, "os::strdup_check_oom");
627 }
628 return p;
629 }
630
631
632 #define paranoid 0 /* only set to 1 if you suspect checking code has bug */
633
634 #ifdef ASSERT
635
verify_memory(void * ptr)636 static void verify_memory(void* ptr) {
637 GuardedMemory guarded(ptr);
638 if (!guarded.verify_guards()) {
639 LogTarget(Warning, malloc, free) lt;
640 ResourceMark rm;
641 LogStream ls(lt);
642 ls.print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees);
643 ls.print_cr("## memory stomp:");
644 guarded.print_on(&ls);
645 fatal("memory stomping error");
646 }
647 }
648
649 #endif
650
651 //
652 // This function supports testing of the malloc out of memory
653 // condition without really running the system out of memory.
654 //
has_reached_max_malloc_test_peak(size_t alloc_size)655 static bool has_reached_max_malloc_test_peak(size_t alloc_size) {
656 if (MallocMaxTestWords > 0) {
657 size_t words = (alloc_size / BytesPerWord);
658
659 if ((cur_malloc_words + words) > MallocMaxTestWords) {
660 return true;
661 }
662 Atomic::add(&cur_malloc_words, words);
663 }
664 return false;
665 }
666
malloc(size_t size,MEMFLAGS flags)667 void* os::malloc(size_t size, MEMFLAGS flags) {
668 return os::malloc(size, flags, CALLER_PC);
669 }
670
malloc(size_t size,MEMFLAGS memflags,const NativeCallStack & stack)671 void* os::malloc(size_t size, MEMFLAGS memflags, const NativeCallStack& stack) {
672 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
673 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
674
675 // Since os::malloc can be called when the libjvm.{dll,so} is
676 // first loaded and we don't have a thread yet we must accept NULL also here.
677 assert(!os::ThreadCrashProtection::is_crash_protected(Thread::current_or_null()),
678 "malloc() not allowed when crash protection is set");
679
680 if (size == 0) {
681 // return a valid pointer if size is zero
682 // if NULL is returned the calling functions assume out of memory.
683 size = 1;
684 }
685
686 // NMT support
687 NMT_TrackingLevel level = MemTracker::tracking_level();
688 size_t nmt_header_size = MemTracker::malloc_header_size(level);
689
690 #ifndef ASSERT
691 const size_t alloc_size = size + nmt_header_size;
692 #else
693 const size_t alloc_size = GuardedMemory::get_total_size(size + nmt_header_size);
694 if (size + nmt_header_size > alloc_size) { // Check for rollover.
695 return NULL;
696 }
697 #endif
698
699 // For the test flag -XX:MallocMaxTestWords
700 if (has_reached_max_malloc_test_peak(size)) {
701 return NULL;
702 }
703
704 u_char* ptr;
705 ptr = (u_char*)::malloc(alloc_size);
706
707 #ifdef ASSERT
708 if (ptr == NULL) {
709 return NULL;
710 }
711 // Wrap memory with guard
712 GuardedMemory guarded(ptr, size + nmt_header_size);
713 ptr = guarded.get_user_ptr();
714
715 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) {
716 log_warning(malloc, free)("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr));
717 breakpoint();
718 }
719 if (paranoid) {
720 verify_memory(ptr);
721 }
722 #endif
723
724 // we do not track guard memory
725 return MemTracker::record_malloc((address)ptr, size, memflags, stack, level);
726 }
727
realloc(void * memblock,size_t size,MEMFLAGS flags)728 void* os::realloc(void *memblock, size_t size, MEMFLAGS flags) {
729 return os::realloc(memblock, size, flags, CALLER_PC);
730 }
731
realloc(void * memblock,size_t size,MEMFLAGS memflags,const NativeCallStack & stack)732 void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, const NativeCallStack& stack) {
733
734 // For the test flag -XX:MallocMaxTestWords
735 if (has_reached_max_malloc_test_peak(size)) {
736 return NULL;
737 }
738
739 if (size == 0) {
740 // return a valid pointer if size is zero
741 // if NULL is returned the calling functions assume out of memory.
742 size = 1;
743 }
744
745 #ifndef ASSERT
746 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
747 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
748 // NMT support
749 NMT_TrackingLevel level = MemTracker::tracking_level();
750 void* membase = MemTracker::record_free(memblock, level);
751 size_t nmt_header_size = MemTracker::malloc_header_size(level);
752 void* ptr = ::realloc(membase, size + nmt_header_size);
753 return MemTracker::record_malloc(ptr, size, memflags, stack, level);
754 #else
755 if (memblock == NULL) {
756 return os::malloc(size, memflags, stack);
757 }
758 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
759 log_warning(malloc, free)("os::realloc caught " PTR_FORMAT, p2i(memblock));
760 breakpoint();
761 }
762 // NMT support
763 void* membase = MemTracker::malloc_base(memblock);
764 verify_memory(membase);
765 // always move the block
766 void* ptr = os::malloc(size, memflags, stack);
767 // Copy to new memory if malloc didn't fail
768 if (ptr != NULL ) {
769 GuardedMemory guarded(MemTracker::malloc_base(memblock));
770 // Guard's user data contains NMT header
771 size_t memblock_size = guarded.get_user_size() - MemTracker::malloc_header_size(memblock);
772 memcpy(ptr, memblock, MIN2(size, memblock_size));
773 if (paranoid) {
774 verify_memory(MemTracker::malloc_base(ptr));
775 }
776 os::free(memblock);
777 }
778 return ptr;
779 #endif
780 }
781
782 // handles NULL pointers
free(void * memblock)783 void os::free(void *memblock) {
784 NOT_PRODUCT(inc_stat_counter(&num_frees, 1));
785 #ifdef ASSERT
786 if (memblock == NULL) return;
787 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
788 log_warning(malloc, free)("os::free caught " PTR_FORMAT, p2i(memblock));
789 breakpoint();
790 }
791 void* membase = MemTracker::record_free(memblock, MemTracker::tracking_level());
792 verify_memory(membase);
793
794 GuardedMemory guarded(membase);
795 size_t size = guarded.get_user_size();
796 inc_stat_counter(&free_bytes, size);
797 membase = guarded.release_for_freeing();
798 ::free(membase);
799 #else
800 void* membase = MemTracker::record_free(memblock, MemTracker::tracking_level());
801 ::free(membase);
802 #endif
803 }
804
init_random(unsigned int initval)805 void os::init_random(unsigned int initval) {
806 _rand_seed = initval;
807 }
808
809
random_helper(unsigned int rand_seed)810 static int random_helper(unsigned int rand_seed) {
811 /* standard, well-known linear congruential random generator with
812 * next_rand = (16807*seed) mod (2**31-1)
813 * see
814 * (1) "Random Number Generators: Good Ones Are Hard to Find",
815 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988),
816 * (2) "Two Fast Implementations of the 'Minimal Standard' Random
817 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88.
818 */
819 const unsigned int a = 16807;
820 const unsigned int m = 2147483647;
821 const int q = m / a; assert(q == 127773, "weird math");
822 const int r = m % a; assert(r == 2836, "weird math");
823
824 // compute az=2^31p+q
825 unsigned int lo = a * (rand_seed & 0xFFFF);
826 unsigned int hi = a * (rand_seed >> 16);
827 lo += (hi & 0x7FFF) << 16;
828
829 // if q overflowed, ignore the overflow and increment q
830 if (lo > m) {
831 lo &= m;
832 ++lo;
833 }
834 lo += hi >> 15;
835
836 // if (p+q) overflowed, ignore the overflow and increment (p+q)
837 if (lo > m) {
838 lo &= m;
839 ++lo;
840 }
841 return lo;
842 }
843
random()844 int os::random() {
845 // Make updating the random seed thread safe.
846 while (true) {
847 unsigned int seed = _rand_seed;
848 unsigned int rand = random_helper(seed);
849 if (Atomic::cmpxchg(&_rand_seed, seed, rand) == seed) {
850 return static_cast<int>(rand);
851 }
852 }
853 }
854
855 // The INITIALIZED state is distinguished from the SUSPENDED state because the
856 // conditions in which a thread is first started are different from those in which
857 // a suspension is resumed. These differences make it hard for us to apply the
858 // tougher checks when starting threads that we want to do when resuming them.
859 // However, when start_thread is called as a result of Thread.start, on a Java
860 // thread, the operation is synchronized on the Java Thread object. So there
861 // cannot be a race to start the thread and hence for the thread to exit while
862 // we are working on it. Non-Java threads that start Java threads either have
863 // to do so in a context in which races are impossible, or should do appropriate
864 // locking.
865
start_thread(Thread * thread)866 void os::start_thread(Thread* thread) {
867 // guard suspend/resume
868 MutexLocker ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag);
869 OSThread* osthread = thread->osthread();
870 osthread->set_state(RUNNABLE);
871 pd_start_thread(thread);
872 }
873
abort(bool dump_core)874 void os::abort(bool dump_core) {
875 abort(dump_core && CreateCoredumpOnCrash, NULL, NULL);
876 }
877
878 //---------------------------------------------------------------------------
879 // Helper functions for fatal error handler
880
print_hex_dump(outputStream * st,address start,address end,int unitsize)881 void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) {
882 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking");
883
884 start = align_down(start, unitsize);
885
886 int cols = 0;
887 int cols_per_line = 0;
888 switch (unitsize) {
889 case 1: cols_per_line = 16; break;
890 case 2: cols_per_line = 8; break;
891 case 4: cols_per_line = 4; break;
892 case 8: cols_per_line = 2; break;
893 default: return;
894 }
895
896 address p = start;
897 st->print(PTR_FORMAT ": ", p2i(start));
898 while (p < end) {
899 if (is_readable_pointer(p)) {
900 switch (unitsize) {
901 case 1: st->print("%02x", *(u1*)p); break;
902 case 2: st->print("%04x", *(u2*)p); break;
903 case 4: st->print("%08x", *(u4*)p); break;
904 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break;
905 }
906 } else {
907 st->print("%*.*s", 2*unitsize, 2*unitsize, "????????????????");
908 }
909 p += unitsize;
910 cols++;
911 if (cols >= cols_per_line && p < end) {
912 cols = 0;
913 st->cr();
914 st->print(PTR_FORMAT ": ", p2i(p));
915 } else {
916 st->print(" ");
917 }
918 }
919 st->cr();
920 }
921
print_dhm(outputStream * st,const char * startStr,long sec)922 void os::print_dhm(outputStream* st, const char* startStr, long sec) {
923 long days = sec/86400;
924 long hours = (sec/3600) - (days * 24);
925 long minutes = (sec/60) - (days * 1440) - (hours * 60);
926 if (startStr == NULL) startStr = "";
927 st->print_cr("%s %ld days %ld:%02ld hours", startStr, days, hours, minutes);
928 }
929
print_instructions(outputStream * st,address pc,int unitsize)930 void os::print_instructions(outputStream* st, address pc, int unitsize) {
931 st->print_cr("Instructions: (pc=" PTR_FORMAT ")", p2i(pc));
932 print_hex_dump(st, pc - 256, pc + 256, unitsize);
933 }
934
print_environment_variables(outputStream * st,const char ** env_list)935 void os::print_environment_variables(outputStream* st, const char** env_list) {
936 if (env_list) {
937 st->print_cr("Environment Variables:");
938
939 for (int i = 0; env_list[i] != NULL; i++) {
940 char *envvar = ::getenv(env_list[i]);
941 if (envvar != NULL) {
942 st->print("%s", env_list[i]);
943 st->print("=");
944 st->print_cr("%s", envvar);
945 }
946 }
947 }
948 }
949
print_cpu_info(outputStream * st,char * buf,size_t buflen)950 void os::print_cpu_info(outputStream* st, char* buf, size_t buflen) {
951 // cpu
952 st->print("CPU:");
953 st->print("total %d", os::processor_count());
954 // It's not safe to query number of active processors after crash
955 // st->print("(active %d)", os::active_processor_count()); but we can
956 // print the initial number of active processors.
957 // We access the raw value here because the assert in the accessor will
958 // fail if the crash occurs before initialization of this value.
959 st->print(" (initial active %d)", _initial_active_processor_count);
960 st->print(" %s", VM_Version::features_string());
961 st->cr();
962 pd_print_cpu_info(st, buf, buflen);
963 }
964
965 // Print a one line string summarizing the cpu, number of cores, memory, and operating system version
print_summary_info(outputStream * st,char * buf,size_t buflen)966 void os::print_summary_info(outputStream* st, char* buf, size_t buflen) {
967 st->print("Host: ");
968 #ifndef PRODUCT
969 if (get_host_name(buf, buflen)) {
970 st->print("%s, ", buf);
971 }
972 #endif // PRODUCT
973 get_summary_cpu_info(buf, buflen);
974 st->print("%s, ", buf);
975 size_t mem = physical_memory()/G;
976 if (mem == 0) { // for low memory systems
977 mem = physical_memory()/M;
978 st->print("%d cores, " SIZE_FORMAT "M, ", processor_count(), mem);
979 } else {
980 st->print("%d cores, " SIZE_FORMAT "G, ", processor_count(), mem);
981 }
982 get_summary_os_info(buf, buflen);
983 st->print_raw(buf);
984 st->cr();
985 }
986
print_date_and_time(outputStream * st,char * buf,size_t buflen)987 void os::print_date_and_time(outputStream *st, char* buf, size_t buflen) {
988 const int secs_per_day = 86400;
989 const int secs_per_hour = 3600;
990 const int secs_per_min = 60;
991
992 time_t tloc;
993 (void)time(&tloc);
994 char* timestring = ctime(&tloc); // ctime adds newline.
995 // edit out the newline
996 char* nl = strchr(timestring, '\n');
997 if (nl != NULL) {
998 *nl = '\0';
999 }
1000
1001 struct tm tz;
1002 if (localtime_pd(&tloc, &tz) != NULL) {
1003 ::strftime(buf, buflen, "%Z", &tz);
1004 st->print("Time: %s %s", timestring, buf);
1005 } else {
1006 st->print("Time: %s", timestring);
1007 }
1008
1009 double t = os::elapsedTime();
1010 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in
1011 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int
1012 // before printf. We lost some precision, but who cares?
1013 int eltime = (int)t; // elapsed time in seconds
1014
1015 // print elapsed time in a human-readable format:
1016 int eldays = eltime / secs_per_day;
1017 int day_secs = eldays * secs_per_day;
1018 int elhours = (eltime - day_secs) / secs_per_hour;
1019 int hour_secs = elhours * secs_per_hour;
1020 int elmins = (eltime - day_secs - hour_secs) / secs_per_min;
1021 int minute_secs = elmins * secs_per_min;
1022 int elsecs = (eltime - day_secs - hour_secs - minute_secs);
1023 st->print_cr(" elapsed time: %d seconds (%dd %dh %dm %ds)", eltime, eldays, elhours, elmins, elsecs);
1024 }
1025
1026
1027 // Check if pointer can be read from (4-byte read access).
1028 // Helps to prove validity of a not-NULL pointer.
1029 // Returns true in very early stages of VM life when stub is not yet generated.
1030 #define SAFEFETCH_DEFAULT true
is_readable_pointer(const void * p)1031 bool os::is_readable_pointer(const void* p) {
1032 if (!CanUseSafeFetch32()) {
1033 return SAFEFETCH_DEFAULT;
1034 }
1035 int* const aligned = (int*) align_down((intptr_t)p, 4);
1036 int cafebabe = 0xcafebabe; // tester value 1
1037 int deadbeef = 0xdeadbeef; // tester value 2
1038 return (SafeFetch32(aligned, cafebabe) != cafebabe) || (SafeFetch32(aligned, deadbeef) != deadbeef);
1039 }
1040
is_readable_range(const void * from,const void * to)1041 bool os::is_readable_range(const void* from, const void* to) {
1042 if ((uintptr_t)from >= (uintptr_t)to) return false;
1043 for (uintptr_t p = align_down((uintptr_t)from, min_page_size()); p < (uintptr_t)to; p += min_page_size()) {
1044 if (!is_readable_pointer((const void*)p)) {
1045 return false;
1046 }
1047 }
1048 return true;
1049 }
1050
1051
1052 // moved from debug.cpp (used to be find()) but still called from there
1053 // The verbose parameter is only set by the debug code in one case
print_location(outputStream * st,intptr_t x,bool verbose)1054 void os::print_location(outputStream* st, intptr_t x, bool verbose) {
1055 address addr = (address)x;
1056 // Handle NULL first, so later checks don't need to protect against it.
1057 if (addr == NULL) {
1058 st->print_cr("0x0 is NULL");
1059 return;
1060 }
1061
1062 // Check if addr points into a code blob.
1063 CodeBlob* b = CodeCache::find_blob_unsafe(addr);
1064 if (b != NULL) {
1065 b->dump_for_addr(addr, st, verbose);
1066 return;
1067 }
1068
1069 // Check if addr points into Java heap.
1070 if (Universe::heap()->print_location(st, addr)) {
1071 return;
1072 }
1073
1074 bool accessible = is_readable_pointer(addr);
1075
1076 // Check if addr is a JNI handle.
1077 if (align_down((intptr_t)addr, sizeof(intptr_t)) != 0 && accessible) {
1078 if (JNIHandles::is_global_handle((jobject) addr)) {
1079 st->print_cr(INTPTR_FORMAT " is a global jni handle", p2i(addr));
1080 return;
1081 }
1082 if (JNIHandles::is_weak_global_handle((jobject) addr)) {
1083 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", p2i(addr));
1084 return;
1085 }
1086 #ifndef PRODUCT
1087 // we don't keep the block list in product mode
1088 if (JNIHandles::is_local_handle((jobject) addr)) {
1089 st->print_cr(INTPTR_FORMAT " is a local jni handle", p2i(addr));
1090 return;
1091 }
1092 #endif
1093 }
1094
1095 // Check if addr belongs to a Java thread.
1096 for (JavaThreadIteratorWithHandle jtiwh; JavaThread *thread = jtiwh.next(); ) {
1097 // If the addr is a java thread print information about that.
1098 if (addr == (address)thread) {
1099 if (verbose) {
1100 thread->print_on(st);
1101 } else {
1102 st->print_cr(INTPTR_FORMAT " is a thread", p2i(addr));
1103 }
1104 return;
1105 }
1106 // If the addr is in the stack region for this thread then report that
1107 // and print thread info
1108 if (thread->on_local_stack(addr)) {
1109 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: "
1110 INTPTR_FORMAT, p2i(addr), p2i(thread));
1111 if (verbose) thread->print_on(st);
1112 return;
1113 }
1114 }
1115
1116 // Check if in metaspace and print types that have vptrs
1117 if (Metaspace::contains(addr)) {
1118 if (Klass::is_valid((Klass*)addr)) {
1119 st->print_cr(INTPTR_FORMAT " is a pointer to class: ", p2i(addr));
1120 ((Klass*)addr)->print_on(st);
1121 } else if (Method::is_valid_method((const Method*)addr)) {
1122 ((Method*)addr)->print_value_on(st);
1123 st->cr();
1124 } else {
1125 // Use addr->print() from the debugger instead (not here)
1126 st->print_cr(INTPTR_FORMAT " is pointing into metadata", p2i(addr));
1127 }
1128 return;
1129 }
1130
1131 // Compressed klass needs to be decoded first.
1132 #ifdef _LP64
1133 if (UseCompressedClassPointers && ((uintptr_t)addr &~ (uintptr_t)max_juint) == 0) {
1134 narrowKlass narrow_klass = (narrowKlass)(uintptr_t)addr;
1135 Klass* k = CompressedKlassPointers::decode_raw(narrow_klass);
1136
1137 if (Klass::is_valid(k)) {
1138 st->print_cr(UINT32_FORMAT " is a compressed pointer to class: " INTPTR_FORMAT, narrow_klass, p2i((HeapWord*)k));
1139 k->print_on(st);
1140 return;
1141 }
1142 }
1143 #endif
1144
1145 // Try an OS specific find
1146 if (os::find(addr, st)) {
1147 return;
1148 }
1149
1150 if (accessible) {
1151 st->print(INTPTR_FORMAT " points into unknown readable memory:", p2i(addr));
1152 for (address p = addr; p < align_up(addr + 1, sizeof(intptr_t)); ++p) {
1153 st->print(" %02x", *(u1*)p);
1154 }
1155 st->cr();
1156 return;
1157 }
1158
1159 st->print_cr(INTPTR_FORMAT " is an unknown value", p2i(addr));
1160 }
1161
1162 // Looks like all platforms can use the same function to check if C
1163 // stack is walkable beyond current frame. The check for fp() is not
1164 // necessary on Sparc, but it's harmless.
is_first_C_frame(frame * fr)1165 bool os::is_first_C_frame(frame* fr) {
1166 // Load up sp, fp, sender sp and sender fp, check for reasonable values.
1167 // Check usp first, because if that's bad the other accessors may fault
1168 // on some architectures. Ditto ufp second, etc.
1169 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1);
1170 // sp on amd can be 32 bit aligned.
1171 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1);
1172
1173 uintptr_t usp = (uintptr_t)fr->sp();
1174 if ((usp & sp_align_mask) != 0) return true;
1175
1176 uintptr_t ufp = (uintptr_t)fr->fp();
1177 if ((ufp & fp_align_mask) != 0) return true;
1178
1179 uintptr_t old_sp = (uintptr_t)fr->sender_sp();
1180 if ((old_sp & sp_align_mask) != 0) return true;
1181 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true;
1182
1183 uintptr_t old_fp = (uintptr_t)fr->link();
1184 if ((old_fp & fp_align_mask) != 0) return true;
1185 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true;
1186
1187 // stack grows downwards; if old_fp is below current fp or if the stack
1188 // frame is too large, either the stack is corrupted or fp is not saved
1189 // on stack (i.e. on x86, ebp may be used as general register). The stack
1190 // is not walkable beyond current frame.
1191 if (old_fp < ufp) return true;
1192 if (old_fp - ufp > 64 * K) return true;
1193
1194 return false;
1195 }
1196
1197
1198 // Set up the boot classpath.
1199
format_boot_path(const char * format_string,const char * home,int home_len,char fileSep,char pathSep)1200 char* os::format_boot_path(const char* format_string,
1201 const char* home,
1202 int home_len,
1203 char fileSep,
1204 char pathSep) {
1205 assert((fileSep == '/' && pathSep == ':') ||
1206 (fileSep == '\\' && pathSep == ';'), "unexpected separator chars");
1207
1208 // Scan the format string to determine the length of the actual
1209 // boot classpath, and handle platform dependencies as well.
1210 int formatted_path_len = 0;
1211 const char* p;
1212 for (p = format_string; *p != 0; ++p) {
1213 if (*p == '%') formatted_path_len += home_len - 1;
1214 ++formatted_path_len;
1215 }
1216
1217 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal);
1218
1219 // Create boot classpath from format, substituting separator chars and
1220 // java home directory.
1221 char* q = formatted_path;
1222 for (p = format_string; *p != 0; ++p) {
1223 switch (*p) {
1224 case '%':
1225 strcpy(q, home);
1226 q += home_len;
1227 break;
1228 case '/':
1229 *q++ = fileSep;
1230 break;
1231 case ':':
1232 *q++ = pathSep;
1233 break;
1234 default:
1235 *q++ = *p;
1236 }
1237 }
1238 *q = '\0';
1239
1240 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched");
1241 return formatted_path;
1242 }
1243
1244 // This function is a proxy to fopen, it tries to add a non standard flag ('e' or 'N')
1245 // that ensures automatic closing of the file on exec. If it can not find support in
1246 // the underlying c library, it will make an extra system call (fcntl) to ensure automatic
1247 // closing of the file on exec.
fopen(const char * path,const char * mode)1248 FILE* os::fopen(const char* path, const char* mode) {
1249 char modified_mode[20];
1250 assert(strlen(mode) + 1 < sizeof(modified_mode), "mode chars plus one extra must fit in buffer");
1251 sprintf(modified_mode, "%s" LINUX_ONLY("e") BSD_ONLY("e") WINDOWS_ONLY("N"), mode);
1252 FILE* file = ::fopen(path, modified_mode);
1253
1254 #if !(defined LINUX || defined BSD || defined _WINDOWS)
1255 // assume fcntl FD_CLOEXEC support as a backup solution when 'e' or 'N'
1256 // is not supported as mode in fopen
1257 if (file != NULL) {
1258 int fd = fileno(file);
1259 if (fd != -1) {
1260 int fd_flags = fcntl(fd, F_GETFD);
1261 if (fd_flags != -1) {
1262 fcntl(fd, F_SETFD, fd_flags | FD_CLOEXEC);
1263 }
1264 }
1265 }
1266 #endif
1267
1268 return file;
1269 }
1270
set_boot_path(char fileSep,char pathSep)1271 bool os::set_boot_path(char fileSep, char pathSep) {
1272 const char* home = Arguments::get_java_home();
1273 int home_len = (int)strlen(home);
1274
1275 struct stat st;
1276
1277 // modular image if "modules" jimage exists
1278 char* jimage = format_boot_path("%/lib/" MODULES_IMAGE_NAME, home, home_len, fileSep, pathSep);
1279 if (jimage == NULL) return false;
1280 bool has_jimage = (os::stat(jimage, &st) == 0);
1281 if (has_jimage) {
1282 Arguments::set_sysclasspath(jimage, true);
1283 FREE_C_HEAP_ARRAY(char, jimage);
1284 return true;
1285 }
1286 FREE_C_HEAP_ARRAY(char, jimage);
1287
1288 // check if developer build with exploded modules
1289 char* base_classes = format_boot_path("%/modules/" JAVA_BASE_NAME, home, home_len, fileSep, pathSep);
1290 if (base_classes == NULL) return false;
1291 if (os::stat(base_classes, &st) == 0) {
1292 Arguments::set_sysclasspath(base_classes, false);
1293 FREE_C_HEAP_ARRAY(char, base_classes);
1294 return true;
1295 }
1296 FREE_C_HEAP_ARRAY(char, base_classes);
1297
1298 return false;
1299 }
1300
1301 // Splits a path, based on its separator, the number of
1302 // elements is returned back in "elements".
1303 // file_name_length is used as a modifier for each path's
1304 // length when compared to JVM_MAXPATHLEN. So if you know
1305 // each returned path will have something appended when
1306 // in use, you can pass the length of that in
1307 // file_name_length, to ensure we detect if any path
1308 // exceeds the maximum path length once prepended onto
1309 // the sub-path/file name.
1310 // It is the callers responsibility to:
1311 // a> check the value of "elements", which may be 0.
1312 // b> ignore any empty path elements
1313 // c> free up the data.
split_path(const char * path,size_t * elements,size_t file_name_length)1314 char** os::split_path(const char* path, size_t* elements, size_t file_name_length) {
1315 *elements = (size_t)0;
1316 if (path == NULL || strlen(path) == 0 || file_name_length == (size_t)NULL) {
1317 return NULL;
1318 }
1319 const char psepchar = *os::path_separator();
1320 char* inpath = NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal);
1321 strcpy(inpath, path);
1322 size_t count = 1;
1323 char* p = strchr(inpath, psepchar);
1324 // Get a count of elements to allocate memory
1325 while (p != NULL) {
1326 count++;
1327 p++;
1328 p = strchr(p, psepchar);
1329 }
1330
1331 char** opath = NEW_C_HEAP_ARRAY(char*, count, mtInternal);
1332
1333 // do the actual splitting
1334 p = inpath;
1335 for (size_t i = 0 ; i < count ; i++) {
1336 size_t len = strcspn(p, os::path_separator());
1337 if (len + file_name_length > JVM_MAXPATHLEN) {
1338 // release allocated storage before exiting the vm
1339 free_array_of_char_arrays(opath, i++);
1340 vm_exit_during_initialization("The VM tried to use a path that exceeds the maximum path length for "
1341 "this system. Review path-containing parameters and properties, such as "
1342 "sun.boot.library.path, to identify potential sources for this path.");
1343 }
1344 // allocate the string and add terminator storage
1345 char* s = NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
1346 strncpy(s, p, len);
1347 s[len] = '\0';
1348 opath[i] = s;
1349 p += len + 1;
1350 }
1351 FREE_C_HEAP_ARRAY(char, inpath);
1352 *elements = count;
1353 return opath;
1354 }
1355
1356 // Returns true if the current stack pointer is above the stack shadow
1357 // pages, false otherwise.
stack_shadow_pages_available(Thread * thread,const methodHandle & method,address sp)1358 bool os::stack_shadow_pages_available(Thread *thread, const methodHandle& method, address sp) {
1359 if (!thread->is_Java_thread()) return false;
1360 // Check if we have StackShadowPages above the yellow zone. This parameter
1361 // is dependent on the depth of the maximum VM call stack possible from
1362 // the handler for stack overflow. 'instanceof' in the stack overflow
1363 // handler or a println uses at least 8k stack of VM and native code
1364 // respectively.
1365 const int framesize_in_bytes =
1366 Interpreter::size_top_interpreter_activation(method()) * wordSize;
1367
1368 address limit = ((JavaThread*)thread)->stack_end() +
1369 (JavaThread::stack_guard_zone_size() + JavaThread::stack_shadow_zone_size());
1370
1371 return sp > (limit + framesize_in_bytes);
1372 }
1373
page_size_for_region(size_t region_size,size_t min_pages,bool must_be_aligned)1374 size_t os::page_size_for_region(size_t region_size, size_t min_pages, bool must_be_aligned) {
1375 assert(min_pages > 0, "sanity");
1376 if (UseLargePages) {
1377 const size_t max_page_size = region_size / min_pages;
1378
1379 for (size_t i = 0; _page_sizes[i] != 0; ++i) {
1380 const size_t page_size = _page_sizes[i];
1381 if (page_size <= max_page_size) {
1382 if (!must_be_aligned || is_aligned(region_size, page_size)) {
1383 return page_size;
1384 }
1385 }
1386 }
1387 }
1388
1389 return vm_page_size();
1390 }
1391
page_size_for_region_aligned(size_t region_size,size_t min_pages)1392 size_t os::page_size_for_region_aligned(size_t region_size, size_t min_pages) {
1393 return page_size_for_region(region_size, min_pages, true);
1394 }
1395
page_size_for_region_unaligned(size_t region_size,size_t min_pages)1396 size_t os::page_size_for_region_unaligned(size_t region_size, size_t min_pages) {
1397 return page_size_for_region(region_size, min_pages, false);
1398 }
1399
errno_to_string(int e,bool short_text)1400 static const char* errno_to_string (int e, bool short_text) {
1401 #define ALL_SHARED_ENUMS(X) \
1402 X(E2BIG, "Argument list too long") \
1403 X(EACCES, "Permission denied") \
1404 X(EADDRINUSE, "Address in use") \
1405 X(EADDRNOTAVAIL, "Address not available") \
1406 X(EAFNOSUPPORT, "Address family not supported") \
1407 X(EAGAIN, "Resource unavailable, try again") \
1408 X(EALREADY, "Connection already in progress") \
1409 X(EBADF, "Bad file descriptor") \
1410 X(EBADMSG, "Bad message") \
1411 X(EBUSY, "Device or resource busy") \
1412 X(ECANCELED, "Operation canceled") \
1413 X(ECHILD, "No child processes") \
1414 X(ECONNABORTED, "Connection aborted") \
1415 X(ECONNREFUSED, "Connection refused") \
1416 X(ECONNRESET, "Connection reset") \
1417 X(EDEADLK, "Resource deadlock would occur") \
1418 X(EDESTADDRREQ, "Destination address required") \
1419 X(EDOM, "Mathematics argument out of domain of function") \
1420 X(EEXIST, "File exists") \
1421 X(EFAULT, "Bad address") \
1422 X(EFBIG, "File too large") \
1423 X(EHOSTUNREACH, "Host is unreachable") \
1424 X(EIDRM, "Identifier removed") \
1425 X(EILSEQ, "Illegal byte sequence") \
1426 X(EINPROGRESS, "Operation in progress") \
1427 X(EINTR, "Interrupted function") \
1428 X(EINVAL, "Invalid argument") \
1429 X(EIO, "I/O error") \
1430 X(EISCONN, "Socket is connected") \
1431 X(EISDIR, "Is a directory") \
1432 X(ELOOP, "Too many levels of symbolic links") \
1433 X(EMFILE, "Too many open files") \
1434 X(EMLINK, "Too many links") \
1435 X(EMSGSIZE, "Message too large") \
1436 X(ENAMETOOLONG, "Filename too long") \
1437 X(ENETDOWN, "Network is down") \
1438 X(ENETRESET, "Connection aborted by network") \
1439 X(ENETUNREACH, "Network unreachable") \
1440 X(ENFILE, "Too many files open in system") \
1441 X(ENOBUFS, "No buffer space available") \
1442 X(ENODEV, "No such device") \
1443 X(ENOENT, "No such file or directory") \
1444 X(ENOEXEC, "Executable file format error") \
1445 X(ENOLCK, "No locks available") \
1446 X(ENOMEM, "Not enough space") \
1447 X(ENOMSG, "No message of the desired type") \
1448 X(ENOPROTOOPT, "Protocol not available") \
1449 X(ENOSPC, "No space left on device") \
1450 X(ENOSYS, "Function not supported") \
1451 X(ENOTCONN, "The socket is not connected") \
1452 X(ENOTDIR, "Not a directory") \
1453 X(ENOTEMPTY, "Directory not empty") \
1454 X(ENOTSOCK, "Not a socket") \
1455 X(ENOTSUP, "Not supported") \
1456 X(ENOTTY, "Inappropriate I/O control operation") \
1457 X(ENXIO, "No such device or address") \
1458 X(EOPNOTSUPP, "Operation not supported on socket") \
1459 X(EOVERFLOW, "Value too large to be stored in data type") \
1460 X(EPERM, "Operation not permitted") \
1461 X(EPIPE, "Broken pipe") \
1462 X(EPROTO, "Protocol error") \
1463 X(EPROTONOSUPPORT, "Protocol not supported") \
1464 X(EPROTOTYPE, "Protocol wrong type for socket") \
1465 X(ERANGE, "Result too large") \
1466 X(EROFS, "Read-only file system") \
1467 X(ESPIPE, "Invalid seek") \
1468 X(ESRCH, "No such process") \
1469 X(ETIMEDOUT, "Connection timed out") \
1470 X(ETXTBSY, "Text file busy") \
1471 X(EWOULDBLOCK, "Operation would block") \
1472 X(EXDEV, "Cross-device link")
1473
1474 #define DEFINE_ENTRY(e, text) { e, #e, text },
1475
1476 static const struct {
1477 int v;
1478 const char* short_text;
1479 const char* long_text;
1480 } table [] = {
1481
1482 ALL_SHARED_ENUMS(DEFINE_ENTRY)
1483
1484 // The following enums are not defined on all platforms.
1485 #ifdef ESTALE
1486 DEFINE_ENTRY(ESTALE, "Reserved")
1487 #endif
1488 #ifdef EDQUOT
1489 DEFINE_ENTRY(EDQUOT, "Reserved")
1490 #endif
1491 #ifdef EMULTIHOP
1492 DEFINE_ENTRY(EMULTIHOP, "Reserved")
1493 #endif
1494 #ifdef ENODATA
1495 DEFINE_ENTRY(ENODATA, "No message is available on the STREAM head read queue")
1496 #endif
1497 #ifdef ENOLINK
1498 DEFINE_ENTRY(ENOLINK, "Reserved")
1499 #endif
1500 #ifdef ENOSR
1501 DEFINE_ENTRY(ENOSR, "No STREAM resources")
1502 #endif
1503 #ifdef ENOSTR
1504 DEFINE_ENTRY(ENOSTR, "Not a STREAM")
1505 #endif
1506 #ifdef ETIME
1507 DEFINE_ENTRY(ETIME, "Stream ioctl() timeout")
1508 #endif
1509
1510 // End marker.
1511 { -1, "Unknown errno", "Unknown error" }
1512
1513 };
1514
1515 #undef DEFINE_ENTRY
1516 #undef ALL_FLAGS
1517
1518 int i = 0;
1519 while (table[i].v != -1 && table[i].v != e) {
1520 i ++;
1521 }
1522
1523 return short_text ? table[i].short_text : table[i].long_text;
1524
1525 }
1526
strerror(int e)1527 const char* os::strerror(int e) {
1528 return errno_to_string(e, false);
1529 }
1530
errno_name(int e)1531 const char* os::errno_name(int e) {
1532 return errno_to_string(e, true);
1533 }
1534
trace_page_sizes(const char * str,const size_t * page_sizes,int count)1535 void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count) {
1536 LogTarget(Info, pagesize) log;
1537 if (log.is_enabled()) {
1538 LogStream out(log);
1539
1540 out.print("%s: ", str);
1541 for (int i = 0; i < count; ++i) {
1542 out.print(" " SIZE_FORMAT, page_sizes[i]);
1543 }
1544 out.cr();
1545 }
1546 }
1547
1548 #define trace_page_size_params(size) byte_size_in_exact_unit(size), exact_unit_for_byte_size(size)
1549
trace_page_sizes(const char * str,const size_t region_min_size,const size_t region_max_size,const size_t page_size,const char * base,const size_t size)1550 void os::trace_page_sizes(const char* str,
1551 const size_t region_min_size,
1552 const size_t region_max_size,
1553 const size_t page_size,
1554 const char* base,
1555 const size_t size) {
1556
1557 log_info(pagesize)("%s: "
1558 " min=" SIZE_FORMAT "%s"
1559 " max=" SIZE_FORMAT "%s"
1560 " base=" PTR_FORMAT
1561 " page_size=" SIZE_FORMAT "%s"
1562 " size=" SIZE_FORMAT "%s",
1563 str,
1564 trace_page_size_params(region_min_size),
1565 trace_page_size_params(region_max_size),
1566 p2i(base),
1567 trace_page_size_params(page_size),
1568 trace_page_size_params(size));
1569 }
1570
trace_page_sizes_for_requested_size(const char * str,const size_t requested_size,const size_t page_size,const size_t alignment,const char * base,const size_t size)1571 void os::trace_page_sizes_for_requested_size(const char* str,
1572 const size_t requested_size,
1573 const size_t page_size,
1574 const size_t alignment,
1575 const char* base,
1576 const size_t size) {
1577
1578 log_info(pagesize)("%s:"
1579 " req_size=" SIZE_FORMAT "%s"
1580 " base=" PTR_FORMAT
1581 " page_size=" SIZE_FORMAT "%s"
1582 " alignment=" SIZE_FORMAT "%s"
1583 " size=" SIZE_FORMAT "%s",
1584 str,
1585 trace_page_size_params(requested_size),
1586 p2i(base),
1587 trace_page_size_params(page_size),
1588 trace_page_size_params(alignment),
1589 trace_page_size_params(size));
1590 }
1591
1592
1593 // This is the working definition of a server class machine:
1594 // >= 2 physical CPU's and >=2GB of memory, with some fuzz
1595 // because the graphics memory (?) sometimes masks physical memory.
1596 // If you want to change the definition of a server class machine
1597 // on some OS or platform, e.g., >=4GB on Windows platforms,
1598 // then you'll have to parameterize this method based on that state,
1599 // as was done for logical processors here, or replicate and
1600 // specialize this method for each platform. (Or fix os to have
1601 // some inheritance structure and use subclassing. Sigh.)
1602 // If you want some platform to always or never behave as a server
1603 // class machine, change the setting of AlwaysActAsServerClassMachine
1604 // and NeverActAsServerClassMachine in globals*.hpp.
is_server_class_machine()1605 bool os::is_server_class_machine() {
1606 // First check for the early returns
1607 if (NeverActAsServerClassMachine) {
1608 return false;
1609 }
1610 if (AlwaysActAsServerClassMachine) {
1611 return true;
1612 }
1613 // Then actually look at the machine
1614 bool result = false;
1615 const unsigned int server_processors = 2;
1616 const julong server_memory = 2UL * G;
1617 // We seem not to get our full complement of memory.
1618 // We allow some part (1/8?) of the memory to be "missing",
1619 // based on the sizes of DIMMs, and maybe graphics cards.
1620 const julong missing_memory = 256UL * M;
1621
1622 /* Is this a server class machine? */
1623 if ((os::active_processor_count() >= (int)server_processors) &&
1624 (os::physical_memory() >= (server_memory - missing_memory))) {
1625 const unsigned int logical_processors =
1626 VM_Version::logical_processors_per_package();
1627 if (logical_processors > 1) {
1628 const unsigned int physical_packages =
1629 os::active_processor_count() / logical_processors;
1630 if (physical_packages >= server_processors) {
1631 result = true;
1632 }
1633 } else {
1634 result = true;
1635 }
1636 }
1637 return result;
1638 }
1639
initialize_initial_active_processor_count()1640 void os::initialize_initial_active_processor_count() {
1641 assert(_initial_active_processor_count == 0, "Initial active processor count already set.");
1642 _initial_active_processor_count = active_processor_count();
1643 log_debug(os)("Initial active processor count set to %d" , _initial_active_processor_count);
1644 }
1645
run()1646 void os::SuspendedThreadTask::run() {
1647 internal_do_task();
1648 _done = true;
1649 }
1650
create_stack_guard_pages(char * addr,size_t bytes)1651 bool os::create_stack_guard_pages(char* addr, size_t bytes) {
1652 return os::pd_create_stack_guard_pages(addr, bytes);
1653 }
1654
reserve_memory(size_t bytes,char * addr,size_t alignment_hint,int file_desc)1655 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint, int file_desc) {
1656 char* result = NULL;
1657
1658 if (file_desc != -1) {
1659 // Could have called pd_reserve_memory() followed by replace_existing_mapping_with_file_mapping(),
1660 // but AIX may use SHM in which case its more trouble to detach the segment and remap memory to the file.
1661 result = os::map_memory_to_file(addr, bytes, file_desc);
1662 if (result != NULL) {
1663 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC);
1664 }
1665 } else {
1666 result = pd_reserve_memory(bytes, addr, alignment_hint);
1667 if (result != NULL) {
1668 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1669 }
1670 }
1671
1672 return result;
1673 }
1674
reserve_memory(size_t bytes,char * addr,size_t alignment_hint,MEMFLAGS flags)1675 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint,
1676 MEMFLAGS flags) {
1677 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1678 if (result != NULL) {
1679 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1680 MemTracker::record_virtual_memory_type((address)result, flags);
1681 }
1682
1683 return result;
1684 }
1685
attempt_reserve_memory_at(size_t bytes,char * addr,int file_desc)1686 char* os::attempt_reserve_memory_at(size_t bytes, char* addr, int file_desc) {
1687 char* result = NULL;
1688 if (file_desc != -1) {
1689 result = pd_attempt_reserve_memory_at(bytes, addr, file_desc);
1690 if (result != NULL) {
1691 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC);
1692 }
1693 } else {
1694 result = pd_attempt_reserve_memory_at(bytes, addr);
1695 if (result != NULL) {
1696 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1697 }
1698 }
1699 return result;
1700 }
1701
split_reserved_memory(char * base,size_t size,size_t split,bool realloc)1702 void os::split_reserved_memory(char *base, size_t size,
1703 size_t split, bool realloc) {
1704 pd_split_reserved_memory(base, size, split, realloc);
1705 }
1706
commit_memory(char * addr,size_t bytes,bool executable)1707 bool os::commit_memory(char* addr, size_t bytes, bool executable) {
1708 bool res = pd_commit_memory(addr, bytes, executable);
1709 if (res) {
1710 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1711 }
1712 return res;
1713 }
1714
commit_memory(char * addr,size_t size,size_t alignment_hint,bool executable)1715 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint,
1716 bool executable) {
1717 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable);
1718 if (res) {
1719 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1720 }
1721 return res;
1722 }
1723
commit_memory_or_exit(char * addr,size_t bytes,bool executable,const char * mesg)1724 void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable,
1725 const char* mesg) {
1726 pd_commit_memory_or_exit(addr, bytes, executable, mesg);
1727 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1728 }
1729
commit_memory_or_exit(char * addr,size_t size,size_t alignment_hint,bool executable,const char * mesg)1730 void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint,
1731 bool executable, const char* mesg) {
1732 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg);
1733 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1734 }
1735
uncommit_memory(char * addr,size_t bytes)1736 bool os::uncommit_memory(char* addr, size_t bytes) {
1737 bool res;
1738 if (MemTracker::tracking_level() > NMT_minimal) {
1739 Tracker tkr(Tracker::uncommit);
1740 res = pd_uncommit_memory(addr, bytes);
1741 if (res) {
1742 tkr.record((address)addr, bytes);
1743 }
1744 } else {
1745 res = pd_uncommit_memory(addr, bytes);
1746 }
1747 return res;
1748 }
1749
release_memory(char * addr,size_t bytes)1750 bool os::release_memory(char* addr, size_t bytes) {
1751 bool res;
1752 if (MemTracker::tracking_level() > NMT_minimal) {
1753 Tracker tkr(Tracker::release);
1754 res = pd_release_memory(addr, bytes);
1755 if (res) {
1756 tkr.record((address)addr, bytes);
1757 }
1758 } else {
1759 res = pd_release_memory(addr, bytes);
1760 }
1761 return res;
1762 }
1763
pretouch_memory(void * start,void * end,size_t page_size)1764 void os::pretouch_memory(void* start, void* end, size_t page_size) {
1765 for (volatile char *p = (char*)start; p < (char*)end; p += page_size) {
1766 *p = 0;
1767 }
1768 }
1769
map_memory(int fd,const char * file_name,size_t file_offset,char * addr,size_t bytes,bool read_only,bool allow_exec)1770 char* os::map_memory(int fd, const char* file_name, size_t file_offset,
1771 char *addr, size_t bytes, bool read_only,
1772 bool allow_exec) {
1773 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec);
1774 if (result != NULL) {
1775 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC);
1776 }
1777 return result;
1778 }
1779
remap_memory(int fd,const char * file_name,size_t file_offset,char * addr,size_t bytes,bool read_only,bool allow_exec)1780 char* os::remap_memory(int fd, const char* file_name, size_t file_offset,
1781 char *addr, size_t bytes, bool read_only,
1782 bool allow_exec) {
1783 return pd_remap_memory(fd, file_name, file_offset, addr, bytes,
1784 read_only, allow_exec);
1785 }
1786
unmap_memory(char * addr,size_t bytes)1787 bool os::unmap_memory(char *addr, size_t bytes) {
1788 bool result;
1789 if (MemTracker::tracking_level() > NMT_minimal) {
1790 Tracker tkr(Tracker::release);
1791 result = pd_unmap_memory(addr, bytes);
1792 if (result) {
1793 tkr.record((address)addr, bytes);
1794 }
1795 } else {
1796 result = pd_unmap_memory(addr, bytes);
1797 }
1798 return result;
1799 }
1800
free_memory(char * addr,size_t bytes,size_t alignment_hint)1801 void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) {
1802 pd_free_memory(addr, bytes, alignment_hint);
1803 }
1804
realign_memory(char * addr,size_t bytes,size_t alignment_hint)1805 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
1806 pd_realign_memory(addr, bytes, alignment_hint);
1807 }
1808
1809 #ifndef _WINDOWS
1810 /* try to switch state from state "from" to state "to"
1811 * returns the state set after the method is complete
1812 */
switch_state(os::SuspendResume::State from,os::SuspendResume::State to)1813 os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from,
1814 os::SuspendResume::State to)
1815 {
1816 os::SuspendResume::State result = Atomic::cmpxchg(&_state, from, to);
1817 if (result == from) {
1818 // success
1819 return to;
1820 }
1821 return result;
1822 }
1823 #endif
1824
1825 // Convenience wrapper around naked_short_sleep to allow for longer sleep
1826 // times. Only for use by non-JavaThreads.
naked_sleep(jlong millis)1827 void os::naked_sleep(jlong millis) {
1828 assert(!Thread::current()->is_Java_thread(), "not for use by JavaThreads");
1829 const jlong limit = 999;
1830 while (millis > limit) {
1831 naked_short_sleep(limit);
1832 millis -= limit;
1833 }
1834 naked_short_sleep(millis);
1835 }
1836