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
89 DEBUG_ONLY(bool os::_mutex_init_done = false;)
90
91 void os_init_globals() {
92 // Called from init_globals().
93 // See Threads::create_vm() in thread.cpp, and init.cpp.
94 os::init_globals();
95 }
96
97 static time_t get_timezone(const struct tm* time_struct) {
98 #if defined(_ALLBSD_SOURCE)
99 return time_struct->tm_gmtoff;
100 #elif defined(_WINDOWS)
101 long zone;
102 _get_timezone(&zone);
103 return static_cast<time_t>(zone);
104 #else
105 return timezone;
106 #endif
107 }
108
109 int os::snprintf(char* buf, size_t len, const char* fmt, ...) {
110 va_list args;
111 va_start(args, fmt);
112 int result = os::vsnprintf(buf, len, fmt, args);
113 va_end(args);
114 return result;
115 }
116
117 // Fill in buffer with current local time as an ISO-8601 string.
118 // E.g., yyyy-mm-ddThh:mm:ss-zzzz.
119 // Returns buffer, or NULL if it failed.
120 // This would mostly be a call to
121 // strftime(...., "%Y-%m-%d" "T" "%H:%M:%S" "%z", ....)
122 // except that on Windows the %z behaves badly, so we do it ourselves.
123 // Also, people wanted milliseconds on there,
124 // and strftime doesn't do milliseconds.
125 char* os::iso8601_time(char* buffer, size_t buffer_length, bool utc) {
126 // Output will be of the form "YYYY-MM-DDThh:mm:ss.mmm+zzzz\0"
127 // 1 2
128 // 12345678901234567890123456789
129 // format string: "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d"
130 static const size_t needed_buffer = 29;
131
132 // Sanity check the arguments
133 if (buffer == NULL) {
134 assert(false, "NULL buffer");
135 return NULL;
136 }
137 if (buffer_length < needed_buffer) {
138 assert(false, "buffer_length too small");
139 return NULL;
140 }
141 // Get the current time
142 jlong milliseconds_since_19700101 = javaTimeMillis();
143 const int milliseconds_per_microsecond = 1000;
144 const time_t seconds_since_19700101 =
145 milliseconds_since_19700101 / milliseconds_per_microsecond;
146 const int milliseconds_after_second =
147 milliseconds_since_19700101 % milliseconds_per_microsecond;
148 // Convert the time value to a tm and timezone variable
149 struct tm time_struct;
150 if (utc) {
151 if (gmtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
152 assert(false, "Failed gmtime_pd");
153 return NULL;
154 }
155 } else {
156 if (localtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
157 assert(false, "Failed localtime_pd");
158 return NULL;
159 }
160 }
161 const time_t zone = get_timezone(&time_struct);
162
163 // If daylight savings time is in effect,
164 // we are 1 hour East of our time zone
165 const time_t seconds_per_minute = 60;
166 const time_t minutes_per_hour = 60;
167 const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour;
168 time_t UTC_to_local = zone;
169 if (time_struct.tm_isdst > 0) {
170 UTC_to_local = UTC_to_local - seconds_per_hour;
171 }
172
173 // No offset when dealing with UTC
174 if (utc) {
175 UTC_to_local = 0;
176 }
177
178 // Compute the time zone offset.
179 // localtime_pd() sets timezone to the difference (in seconds)
180 // between UTC and and local time.
181 // ISO 8601 says we need the difference between local time and UTC,
182 // we change the sign of the localtime_pd() result.
183 const time_t local_to_UTC = -(UTC_to_local);
184 // Then we have to figure out if if we are ahead (+) or behind (-) UTC.
185 char sign_local_to_UTC = '+';
186 time_t abs_local_to_UTC = local_to_UTC;
187 if (local_to_UTC < 0) {
188 sign_local_to_UTC = '-';
189 abs_local_to_UTC = -(abs_local_to_UTC);
190 }
191 // Convert time zone offset seconds to hours and minutes.
192 const time_t zone_hours = (abs_local_to_UTC / seconds_per_hour);
193 const time_t zone_min =
194 ((abs_local_to_UTC % seconds_per_hour) / seconds_per_minute);
195
196 // Print an ISO 8601 date and time stamp into the buffer
197 const int year = 1900 + time_struct.tm_year;
198 const int month = 1 + time_struct.tm_mon;
199 const int printed = jio_snprintf(buffer, buffer_length,
200 "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d",
201 year,
202 month,
203 time_struct.tm_mday,
204 time_struct.tm_hour,
205 time_struct.tm_min,
206 time_struct.tm_sec,
207 milliseconds_after_second,
208 sign_local_to_UTC,
209 zone_hours,
210 zone_min);
211 if (printed == 0) {
212 assert(false, "Failed jio_printf");
213 return NULL;
214 }
215 return buffer;
216 }
217
218 OSReturn os::set_priority(Thread* thread, ThreadPriority p) {
219 debug_only(Thread::check_for_dangling_thread_pointer(thread);)
220
221 if ((p >= MinPriority && p <= MaxPriority) ||
222 (p == CriticalPriority && thread->is_ConcurrentGC_thread())) {
223 int priority = java_to_os_priority[p];
224 return set_native_priority(thread, priority);
225 } else {
226 assert(false, "Should not happen");
227 return OS_ERR;
228 }
229 }
230
231 // The mapping from OS priority back to Java priority may be inexact because
232 // Java priorities can map M:1 with native priorities. If you want the definite
233 // Java priority then use JavaThread::java_priority()
234 OSReturn os::get_priority(const Thread* const thread, ThreadPriority& priority) {
235 int p;
236 int os_prio;
237 OSReturn ret = get_native_priority(thread, &os_prio);
238 if (ret != OS_OK) return ret;
239
240 if (java_to_os_priority[MaxPriority] > java_to_os_priority[MinPriority]) {
241 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] > os_prio; p--) ;
242 } else {
243 // niceness values are in reverse order
244 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] < os_prio; p--) ;
245 }
246 priority = (ThreadPriority)p;
247 return OS_OK;
248 }
249
250 bool os::dll_build_name(char* buffer, size_t size, const char* fname) {
251 int n = jio_snprintf(buffer, size, "%s%s%s", JNI_LIB_PREFIX, fname, JNI_LIB_SUFFIX);
252 return (n != -1);
253 }
254
255 #if !defined(LINUX) && !defined(_WINDOWS)
256 bool os::committed_in_range(address start, size_t size, address& committed_start, size_t& committed_size) {
257 committed_start = start;
258 committed_size = size;
259 return true;
260 }
261 #endif
262
263 // Helper for dll_locate_lib.
264 // Pass buffer and printbuffer as we already printed the path to buffer
265 // when we called get_current_directory. This way we avoid another buffer
266 // of size MAX_PATH.
267 static bool conc_path_file_and_check(char *buffer, char *printbuffer, size_t printbuflen,
268 const char* pname, char lastchar, const char* fname) {
269
270 // Concatenate path and file name, but don't print double path separators.
271 const char *filesep = (WINDOWS_ONLY(lastchar == ':' ||) lastchar == os::file_separator()[0]) ?
272 "" : os::file_separator();
273 int ret = jio_snprintf(printbuffer, printbuflen, "%s%s%s", pname, filesep, fname);
274 // Check whether file exists.
275 if (ret != -1) {
276 struct stat statbuf;
277 return os::stat(buffer, &statbuf) == 0;
278 }
279 return false;
280 }
281
282 bool os::dll_locate_lib(char *buffer, size_t buflen,
283 const char* pname, const char* fname) {
284 bool retval = false;
285
286 size_t fullfnamelen = strlen(JNI_LIB_PREFIX) + strlen(fname) + strlen(JNI_LIB_SUFFIX);
287 char* fullfname = (char*)NEW_C_HEAP_ARRAY(char, fullfnamelen + 1, mtInternal);
288 if (dll_build_name(fullfname, fullfnamelen + 1, fname)) {
289 const size_t pnamelen = pname ? strlen(pname) : 0;
290
291 if (pnamelen == 0) {
292 // If no path given, use current working directory.
293 const char* p = get_current_directory(buffer, buflen);
294 if (p != NULL) {
295 const size_t plen = strlen(buffer);
296 const char lastchar = buffer[plen - 1];
297 retval = conc_path_file_and_check(buffer, &buffer[plen], buflen - plen,
298 "", lastchar, fullfname);
299 }
300 } else if (strchr(pname, *os::path_separator()) != NULL) {
301 // A list of paths. Search for the path that contains the library.
302 int n;
303 char** pelements = split_path(pname, &n);
304 if (pelements != NULL) {
305 for (int i = 0; i < n; i++) {
306 char* path = pelements[i];
307 // Really shouldn't be NULL, but check can't hurt.
308 size_t plen = (path == NULL) ? 0 : strlen(path);
309 if (plen == 0) {
310 continue; // Skip the empty path values.
311 }
312 const char lastchar = path[plen - 1];
313 retval = conc_path_file_and_check(buffer, buffer, buflen, path, lastchar, fullfname);
314 if (retval) break;
315 }
316 // Release the storage allocated by split_path.
317 for (int i = 0; i < n; i++) {
318 if (pelements[i] != NULL) {
319 FREE_C_HEAP_ARRAY(char, pelements[i]);
320 }
321 }
322 FREE_C_HEAP_ARRAY(char*, pelements);
323 }
324 } else {
325 // A definite path.
326 const char lastchar = pname[pnamelen-1];
327 retval = conc_path_file_and_check(buffer, buffer, buflen, pname, lastchar, fullfname);
328 }
329 }
330
331 FREE_C_HEAP_ARRAY(char*, fullfname);
332 return retval;
333 }
334
335 // --------------------- sun.misc.Signal (optional) ---------------------
336
337
338 // SIGBREAK is sent by the keyboard to query the VM state
339 #ifndef SIGBREAK
340 #define SIGBREAK SIGQUIT
341 #endif
342
343 // sigexitnum_pd is a platform-specific special signal used for terminating the Signal thread.
344
345
346 static void signal_thread_entry(JavaThread* thread, TRAPS) {
347 os::set_priority(thread, NearMaxPriority);
348 while (true) {
349 int sig;
350 {
351 // FIXME : Currently we have not decided what should be the status
352 // for this java thread blocked here. Once we decide about
353 // that we should fix this.
354 sig = os::signal_wait();
355 }
356 if (sig == os::sigexitnum_pd()) {
357 // Terminate the signal thread
358 return;
359 }
360
361 switch (sig) {
362 case SIGBREAK: {
363 // Check if the signal is a trigger to start the Attach Listener - in that
364 // case don't print stack traces.
365 if (!DisableAttachMechanism) {
366 // Attempt to transit state to AL_INITIALIZING.
367 AttachListenerState cur_state = AttachListener::transit_state(AL_INITIALIZING, AL_NOT_INITIALIZED);
368 if (cur_state == AL_INITIALIZING) {
369 // Attach Listener has been started to initialize. Ignore this signal.
370 continue;
371 } else if (cur_state == AL_NOT_INITIALIZED) {
372 // Start to initialize.
373 if (!AttachListener::is_init_trigger()) {
374 // Attach Listener could not be started.
375 // So we need to transit the state to AL_NOT_INITIALIZED.
376 AttachListener::set_state(AL_NOT_INITIALIZED);
377 }
378 continue;
379 } else if (AttachListener::check_socket_file()) {
380 continue;
381 }
382 }
383 // Print stack traces
384 // Any SIGBREAK operations added here should make sure to flush
385 // the output stream (e.g. tty->flush()) after output. See 4803766.
386 // Each module also prints an extra carriage return after its output.
387 VM_PrintThreads op;
388 VMThread::execute(&op);
389 VM_PrintJNI jni_op;
390 VMThread::execute(&jni_op);
391 VM_FindDeadlocks op1(tty);
392 VMThread::execute(&op1);
393 Universe::print_heap_at_SIGBREAK();
394 if (PrintClassHistogram) {
395 VM_GC_HeapInspection op1(tty, true /* force full GC before heap inspection */);
396 VMThread::execute(&op1);
397 }
398 if (JvmtiExport::should_post_data_dump()) {
399 JvmtiExport::post_data_dump();
400 }
401 break;
402 }
403 default: {
404 // Dispatch the signal to java
405 HandleMark hm(THREAD);
406 Klass* klass = SystemDictionary::resolve_or_null(vmSymbols::jdk_internal_misc_Signal(), THREAD);
407 if (klass != NULL) {
408 JavaValue result(T_VOID);
409 JavaCallArguments args;
410 args.push_int(sig);
411 JavaCalls::call_static(
412 &result,
413 klass,
414 vmSymbols::dispatch_name(),
415 vmSymbols::int_void_signature(),
416 &args,
417 THREAD
418 );
419 }
420 if (HAS_PENDING_EXCEPTION) {
421 // tty is initialized early so we don't expect it to be null, but
422 // if it is we can't risk doing an initialization that might
423 // trigger additional out-of-memory conditions
424 if (tty != NULL) {
425 char klass_name[256];
426 char tmp_sig_name[16];
427 const char* sig_name = "UNKNOWN";
428 InstanceKlass::cast(PENDING_EXCEPTION->klass())->
429 name()->as_klass_external_name(klass_name, 256);
430 if (os::exception_name(sig, tmp_sig_name, 16) != NULL)
431 sig_name = tmp_sig_name;
432 warning("Exception %s occurred dispatching signal %s to handler"
433 "- the VM may need to be forcibly terminated",
434 klass_name, sig_name );
435 }
436 CLEAR_PENDING_EXCEPTION;
437 }
438 }
439 }
440 }
441 }
442
443 void os::init_before_ergo() {
444 initialize_initial_active_processor_count();
445 // We need to initialize large page support here because ergonomics takes some
446 // decisions depending on large page support and the calculated large page size.
447 large_page_init();
448
449 // We need to adapt the configured number of stack protection pages given
450 // in 4K pages to the actual os page size. We must do this before setting
451 // up minimal stack sizes etc. in os::init_2().
452 JavaThread::set_stack_red_zone_size (align_up(StackRedPages * 4 * K, vm_page_size()));
453 JavaThread::set_stack_yellow_zone_size (align_up(StackYellowPages * 4 * K, vm_page_size()));
454 JavaThread::set_stack_reserved_zone_size(align_up(StackReservedPages * 4 * K, vm_page_size()));
455 JavaThread::set_stack_shadow_zone_size (align_up(StackShadowPages * 4 * K, vm_page_size()));
456
457 // VM version initialization identifies some characteristics of the
458 // platform that are used during ergonomic decisions.
459 VM_Version::init_before_ergo();
460 }
461
462 void os::initialize_jdk_signal_support(TRAPS) {
463 if (!ReduceSignalUsage) {
464 // Setup JavaThread for processing signals
465 const char thread_name[] = "Signal Dispatcher";
466 Handle string = java_lang_String::create_from_str(thread_name, CHECK);
467
468 // Initialize thread_oop to put it into the system threadGroup
469 Handle thread_group (THREAD, Universe::system_thread_group());
470 Handle thread_oop = JavaCalls::construct_new_instance(SystemDictionary::Thread_klass(),
471 vmSymbols::threadgroup_string_void_signature(),
472 thread_group,
473 string,
474 CHECK);
475
476 Klass* group = SystemDictionary::ThreadGroup_klass();
477 JavaValue result(T_VOID);
478 JavaCalls::call_special(&result,
479 thread_group,
480 group,
481 vmSymbols::add_method_name(),
482 vmSymbols::thread_void_signature(),
483 thread_oop,
484 CHECK);
485
486 { MutexLocker mu(Threads_lock);
487 JavaThread* signal_thread = new JavaThread(&signal_thread_entry);
488
489 // At this point it may be possible that no osthread was created for the
490 // JavaThread due to lack of memory. We would have to throw an exception
491 // in that case. However, since this must work and we do not allow
492 // exceptions anyway, check and abort if this fails.
493 if (signal_thread == NULL || signal_thread->osthread() == NULL) {
494 vm_exit_during_initialization("java.lang.OutOfMemoryError",
495 os::native_thread_creation_failed_msg());
496 }
497
498 java_lang_Thread::set_thread(thread_oop(), signal_thread);
499 java_lang_Thread::set_priority(thread_oop(), NearMaxPriority);
500 java_lang_Thread::set_daemon(thread_oop());
501
502 signal_thread->set_threadObj(thread_oop());
503 Threads::add(signal_thread);
504 Thread::start(signal_thread);
505 }
506 // Handle ^BREAK
507 os::signal(SIGBREAK, os::user_handler());
508 }
509 }
510
511
512 void os::terminate_signal_thread() {
513 if (!ReduceSignalUsage)
514 signal_notify(sigexitnum_pd());
515 }
516
517
518 // --------------------- loading libraries ---------------------
519
520 typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *);
521 extern struct JavaVM_ main_vm;
522
523 static void* _native_java_library = NULL;
524
525 void* os::native_java_library() {
526 if (_native_java_library == NULL) {
527 char buffer[JVM_MAXPATHLEN];
528 char ebuf[1024];
529
530 // Try to load verify dll first. In 1.3 java dll depends on it and is not
531 // always able to find it when the loading executable is outside the JDK.
532 // In order to keep working with 1.2 we ignore any loading errors.
533 if (dll_locate_lib(buffer, sizeof(buffer), Arguments::get_dll_dir(),
534 "verify")) {
535 dll_load(buffer, ebuf, sizeof(ebuf));
536 }
537
538 // Load java dll
539 if (dll_locate_lib(buffer, sizeof(buffer), Arguments::get_dll_dir(),
540 "java")) {
541 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf));
542 }
543 if (_native_java_library == NULL) {
544 vm_exit_during_initialization("Unable to load native library", ebuf);
545 }
546
547 #if defined(__OpenBSD__)
548 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so
549 // ignore errors
550 if (dll_locate_lib(buffer, sizeof(buffer), Arguments::get_dll_dir(),
551 "net")) {
552 dll_load(buffer, ebuf, sizeof(ebuf));
553 }
554 #endif
555 }
556 return _native_java_library;
557 }
558
559 /*
560 * Support for finding Agent_On(Un)Load/Attach<_lib_name> if it exists.
561 * If check_lib == true then we are looking for an
562 * Agent_OnLoad_lib_name or Agent_OnAttach_lib_name function to determine if
563 * this library is statically linked into the image.
564 * If check_lib == false then we will look for the appropriate symbol in the
565 * executable if agent_lib->is_static_lib() == true or in the shared library
566 * referenced by 'handle'.
567 */
568 void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib,
569 const char *syms[], size_t syms_len) {
570 assert(agent_lib != NULL, "sanity check");
571 const char *lib_name;
572 void *handle = agent_lib->os_lib();
573 void *entryName = NULL;
574 char *agent_function_name;
575 size_t i;
576
577 // If checking then use the agent name otherwise test is_static_lib() to
578 // see how to process this lookup
579 lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL);
580 for (i = 0; i < syms_len; i++) {
581 agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path());
582 if (agent_function_name == NULL) {
583 break;
584 }
585 entryName = dll_lookup(handle, agent_function_name);
586 FREE_C_HEAP_ARRAY(char, agent_function_name);
587 if (entryName != NULL) {
588 break;
589 }
590 }
591 return entryName;
592 }
593
594 // See if the passed in agent is statically linked into the VM image.
595 bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
596 size_t syms_len) {
597 void *ret;
598 void *proc_handle;
599 void *save_handle;
600
601 assert(agent_lib != NULL, "sanity check");
602 if (agent_lib->name() == NULL) {
603 return false;
604 }
605 proc_handle = get_default_process_handle();
606 // Check for Agent_OnLoad/Attach_lib_name function
607 save_handle = agent_lib->os_lib();
608 // We want to look in this process' symbol table.
609 agent_lib->set_os_lib(proc_handle);
610 ret = find_agent_function(agent_lib, true, syms, syms_len);
611 if (ret != NULL) {
612 // Found an entry point like Agent_OnLoad_lib_name so we have a static agent
613 agent_lib->set_valid();
614 agent_lib->set_static_lib(true);
615 return true;
616 }
617 agent_lib->set_os_lib(save_handle);
618 return false;
619 }
620
621 // --------------------- heap allocation utilities ---------------------
622
623 char *os::strdup(const char *str, MEMFLAGS flags) {
624 size_t size = strlen(str);
625 char *dup_str = (char *)malloc(size + 1, flags);
626 if (dup_str == NULL) return NULL;
627 strcpy(dup_str, str);
628 return dup_str;
629 }
630
631 char* os::strdup_check_oom(const char* str, MEMFLAGS flags) {
632 char* p = os::strdup(str, flags);
633 if (p == NULL) {
634 vm_exit_out_of_memory(strlen(str) + 1, OOM_MALLOC_ERROR, "os::strdup_check_oom");
635 }
636 return p;
637 }
638
639
640 #define paranoid 0 /* only set to 1 if you suspect checking code has bug */
641
642 #ifdef ASSERT
643
644 static void verify_memory(void* ptr) {
645 GuardedMemory guarded(ptr);
646 if (!guarded.verify_guards()) {
647 LogTarget(Warning, malloc, free) lt;
648 ResourceMark rm;
649 LogStream ls(lt);
650 ls.print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees);
651 ls.print_cr("## memory stomp:");
652 guarded.print_on(&ls);
653 fatal("memory stomping error");
654 }
655 }
656
657 #endif
658
659 //
660 // This function supports testing of the malloc out of memory
661 // condition without really running the system out of memory.
662 //
663 static bool has_reached_max_malloc_test_peak(size_t alloc_size) {
664 if (MallocMaxTestWords > 0) {
665 size_t words = (alloc_size / BytesPerWord);
666
667 if ((cur_malloc_words + words) > MallocMaxTestWords) {
668 return true;
669 }
670 Atomic::add(words, &cur_malloc_words);
671 }
672 return false;
673 }
674
675 void* os::malloc(size_t size, MEMFLAGS flags) {
676 return os::malloc(size, flags, CALLER_PC);
677 }
678
679 void* os::malloc(size_t size, MEMFLAGS memflags, const NativeCallStack& stack) {
680 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
681 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
682
683 // Since os::malloc can be called when the libjvm.{dll,so} is
684 // first loaded and we don't have a thread yet we must accept NULL also here.
685 assert(!os::ThreadCrashProtection::is_crash_protected(Thread::current_or_null()),
686 "malloc() not allowed when crash protection is set");
687
688 if (size == 0) {
689 // return a valid pointer if size is zero
690 // if NULL is returned the calling functions assume out of memory.
691 size = 1;
692 }
693
694 // NMT support
695 NMT_TrackingLevel level = MemTracker::tracking_level();
696 size_t nmt_header_size = MemTracker::malloc_header_size(level);
697
698 #ifndef ASSERT
699 const size_t alloc_size = size + nmt_header_size;
700 #else
701 const size_t alloc_size = GuardedMemory::get_total_size(size + nmt_header_size);
702 if (size + nmt_header_size > alloc_size) { // Check for rollover.
703 return NULL;
704 }
705 #endif
706
707 // For the test flag -XX:MallocMaxTestWords
708 if (has_reached_max_malloc_test_peak(size)) {
709 return NULL;
710 }
711
712 u_char* ptr;
713 ptr = (u_char*)::malloc(alloc_size);
714
715 #ifdef ASSERT
716 if (ptr == NULL) {
717 return NULL;
718 }
719 // Wrap memory with guard
720 GuardedMemory guarded(ptr, size + nmt_header_size);
721 ptr = guarded.get_user_ptr();
722
723 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) {
724 log_warning(malloc, free)("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr));
725 breakpoint();
726 }
727 if (paranoid) {
728 verify_memory(ptr);
729 }
730 #endif
731
732 // we do not track guard memory
733 return MemTracker::record_malloc((address)ptr, size, memflags, stack, level);
734 }
735
736 void* os::realloc(void *memblock, size_t size, MEMFLAGS flags) {
737 return os::realloc(memblock, size, flags, CALLER_PC);
738 }
739
740 void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, const NativeCallStack& stack) {
741
742 // For the test flag -XX:MallocMaxTestWords
743 if (has_reached_max_malloc_test_peak(size)) {
744 return NULL;
745 }
746
747 if (size == 0) {
748 // return a valid pointer if size is zero
749 // if NULL is returned the calling functions assume out of memory.
750 size = 1;
751 }
752
753 #ifndef ASSERT
754 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
755 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
756 // NMT support
757 void* membase = MemTracker::record_free(memblock);
758 NMT_TrackingLevel level = MemTracker::tracking_level();
759 size_t nmt_header_size = MemTracker::malloc_header_size(level);
760 void* ptr = ::realloc(membase, size + nmt_header_size);
761 return MemTracker::record_malloc(ptr, size, memflags, stack, level);
762 #else
763 if (memblock == NULL) {
764 return os::malloc(size, memflags, stack);
765 }
766 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
767 log_warning(malloc, free)("os::realloc caught " PTR_FORMAT, p2i(memblock));
768 breakpoint();
769 }
770 // NMT support
771 void* membase = MemTracker::malloc_base(memblock);
772 verify_memory(membase);
773 // always move the block
774 void* ptr = os::malloc(size, memflags, stack);
775 // Copy to new memory if malloc didn't fail
776 if (ptr != NULL ) {
777 GuardedMemory guarded(MemTracker::malloc_base(memblock));
778 // Guard's user data contains NMT header
779 size_t memblock_size = guarded.get_user_size() - MemTracker::malloc_header_size(memblock);
780 memcpy(ptr, memblock, MIN2(size, memblock_size));
781 if (paranoid) {
782 verify_memory(MemTracker::malloc_base(ptr));
783 }
784 os::free(memblock);
785 }
786 return ptr;
787 #endif
788 }
789
790
791 void os::free(void *memblock) {
792 NOT_PRODUCT(inc_stat_counter(&num_frees, 1));
793 #ifdef ASSERT
794 if (memblock == NULL) return;
795 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
796 log_warning(malloc, free)("os::free caught " PTR_FORMAT, p2i(memblock));
797 breakpoint();
798 }
799 void* membase = MemTracker::record_free(memblock);
800 verify_memory(membase);
801
802 GuardedMemory guarded(membase);
803 size_t size = guarded.get_user_size();
804 inc_stat_counter(&free_bytes, size);
805 membase = guarded.release_for_freeing();
806 ::free(membase);
807 #else
808 void* membase = MemTracker::record_free(memblock);
809 ::free(membase);
810 #endif
811 }
812
813 void os::init_random(unsigned int initval) {
814 _rand_seed = initval;
815 }
816
817
818 static int random_helper(unsigned int rand_seed) {
819 /* standard, well-known linear congruential random generator with
820 * next_rand = (16807*seed) mod (2**31-1)
821 * see
822 * (1) "Random Number Generators: Good Ones Are Hard to Find",
823 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988),
824 * (2) "Two Fast Implementations of the 'Minimal Standard' Random
825 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88.
826 */
827 const unsigned int a = 16807;
828 const unsigned int m = 2147483647;
829 const int q = m / a; assert(q == 127773, "weird math");
830 const int r = m % a; assert(r == 2836, "weird math");
831
832 // compute az=2^31p+q
833 unsigned int lo = a * (rand_seed & 0xFFFF);
834 unsigned int hi = a * (rand_seed >> 16);
835 lo += (hi & 0x7FFF) << 16;
836
837 // if q overflowed, ignore the overflow and increment q
838 if (lo > m) {
839 lo &= m;
840 ++lo;
841 }
842 lo += hi >> 15;
843
844 // if (p+q) overflowed, ignore the overflow and increment (p+q)
845 if (lo > m) {
846 lo &= m;
847 ++lo;
848 }
849 return lo;
850 }
851
852 int os::random() {
853 // Make updating the random seed thread safe.
854 while (true) {
855 unsigned int seed = _rand_seed;
856 unsigned int rand = random_helper(seed);
857 if (Atomic::cmpxchg(rand, &_rand_seed, seed) == seed) {
858 return static_cast<int>(rand);
859 }
860 }
861 }
862
863 // The INITIALIZED state is distinguished from the SUSPENDED state because the
864 // conditions in which a thread is first started are different from those in which
865 // a suspension is resumed. These differences make it hard for us to apply the
866 // tougher checks when starting threads that we want to do when resuming them.
867 // However, when start_thread is called as a result of Thread.start, on a Java
868 // thread, the operation is synchronized on the Java Thread object. So there
869 // cannot be a race to start the thread and hence for the thread to exit while
870 // we are working on it. Non-Java threads that start Java threads either have
871 // to do so in a context in which races are impossible, or should do appropriate
872 // locking.
873
874 void os::start_thread(Thread* thread) {
875 // guard suspend/resume
876 MutexLocker ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag);
877 OSThread* osthread = thread->osthread();
878 osthread->set_state(RUNNABLE);
879 pd_start_thread(thread);
880 }
881
882 void os::abort(bool dump_core) {
883 abort(dump_core && CreateCoredumpOnCrash, NULL, NULL);
884 }
885
886 //---------------------------------------------------------------------------
887 // Helper functions for fatal error handler
888
889 void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) {
890 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking");
891
892 start = align_down(start, unitsize);
893
894 int cols = 0;
895 int cols_per_line = 0;
896 switch (unitsize) {
897 case 1: cols_per_line = 16; break;
898 case 2: cols_per_line = 8; break;
899 case 4: cols_per_line = 4; break;
900 case 8: cols_per_line = 2; break;
901 default: return;
902 }
903
904 address p = start;
905 st->print(PTR_FORMAT ": ", p2i(start));
906 while (p < end) {
907 if (is_readable_pointer(p)) {
908 switch (unitsize) {
909 case 1: st->print("%02x", *(u1*)p); break;
910 case 2: st->print("%04x", *(u2*)p); break;
911 case 4: st->print("%08x", *(u4*)p); break;
912 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break;
913 }
914 } else {
915 st->print("%*.*s", 2*unitsize, 2*unitsize, "????????????????");
916 }
917 p += unitsize;
918 cols++;
919 if (cols >= cols_per_line && p < end) {
920 cols = 0;
921 st->cr();
922 st->print(PTR_FORMAT ": ", p2i(p));
923 } else {
924 st->print(" ");
925 }
926 }
927 st->cr();
928 }
929
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
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
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
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
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
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
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
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()->is_in(addr)) {
1071 oop o = oopDesc::oop_or_null(addr);
1072 if (o != NULL) {
1073 if ((HeapWord*)o == (HeapWord*)addr) {
1074 st->print(INTPTR_FORMAT " is an oop: ", p2i(addr));
1075 } else {
1076 st->print(INTPTR_FORMAT " is pointing into object: " , p2i(addr));
1077 }
1078 o->print_on(st);
1079 return;
1080 }
1081 } else if (Universe::heap()->is_in_reserved(addr)) {
1082 st->print_cr(INTPTR_FORMAT " is an unallocated location in the heap", p2i(addr));
1083 return;
1084 }
1085
1086 // Compressed oop needs to be decoded first.
1087 #ifdef _LP64
1088 if (UseCompressedOops && ((uintptr_t)addr &~ (uintptr_t)max_juint) == 0) {
1089 narrowOop narrow_oop = (narrowOop)(uintptr_t)addr;
1090 oop o = CompressedOops::decode_raw(narrow_oop);
1091
1092 if (oopDesc::is_valid(o)) {
1093 st->print(UINT32_FORMAT " is a compressed pointer to object: ", narrow_oop);
1094 o->print_on(st);
1095 return;
1096 }
1097 }
1098 #endif
1099
1100 bool accessible = is_readable_pointer(addr);
1101
1102 // Check if addr is a JNI handle.
1103 if (align_down((intptr_t)addr, sizeof(intptr_t)) != 0 && accessible) {
1104 if (JNIHandles::is_global_handle((jobject) addr)) {
1105 st->print_cr(INTPTR_FORMAT " is a global jni handle", p2i(addr));
1106 return;
1107 }
1108 if (JNIHandles::is_weak_global_handle((jobject) addr)) {
1109 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", p2i(addr));
1110 return;
1111 }
1112 #ifndef PRODUCT
1113 // we don't keep the block list in product mode
1114 if (JNIHandles::is_local_handle((jobject) addr)) {
1115 st->print_cr(INTPTR_FORMAT " is a local jni handle", p2i(addr));
1116 return;
1117 }
1118 #endif
1119 }
1120
1121 // Check if addr belongs to a Java thread.
1122 for (JavaThreadIteratorWithHandle jtiwh; JavaThread *thread = jtiwh.next(); ) {
1123 // If the addr is a java thread print information about that.
1124 if (addr == (address)thread) {
1125 if (verbose) {
1126 thread->print_on(st);
1127 } else {
1128 st->print_cr(INTPTR_FORMAT " is a thread", p2i(addr));
1129 }
1130 return;
1131 }
1132 // If the addr is in the stack region for this thread then report that
1133 // and print thread info
1134 if (thread->on_local_stack(addr)) {
1135 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: "
1136 INTPTR_FORMAT, p2i(addr), p2i(thread));
1137 if (verbose) thread->print_on(st);
1138 return;
1139 }
1140 }
1141
1142 // Check if in metaspace and print types that have vptrs
1143 if (Metaspace::contains(addr)) {
1144 if (Klass::is_valid((Klass*)addr)) {
1145 st->print_cr(INTPTR_FORMAT " is a pointer to class: ", p2i(addr));
1146 ((Klass*)addr)->print_on(st);
1147 } else if (Method::is_valid_method((const Method*)addr)) {
1148 ((Method*)addr)->print_value_on(st);
1149 st->cr();
1150 } else {
1151 // Use addr->print() from the debugger instead (not here)
1152 st->print_cr(INTPTR_FORMAT " is pointing into metadata", p2i(addr));
1153 }
1154 return;
1155 }
1156
1157 // Compressed klass needs to be decoded first.
1158 #ifdef _LP64
1159 if (UseCompressedClassPointers && ((uintptr_t)addr &~ (uintptr_t)max_juint) == 0) {
1160 narrowKlass narrow_klass = (narrowKlass)(uintptr_t)addr;
1161 Klass* k = CompressedKlassPointers::decode_raw(narrow_klass);
1162
1163 if (Klass::is_valid(k)) {
1164 st->print_cr(UINT32_FORMAT " is a compressed pointer to class: " INTPTR_FORMAT, narrow_klass, p2i((HeapWord*)k));
1165 k->print_on(st);
1166 return;
1167 }
1168 }
1169 #endif
1170
1171 // Try an OS specific find
1172 if (os::find(addr, st)) {
1173 return;
1174 }
1175
1176 if (accessible) {
1177 st->print(INTPTR_FORMAT " points into unknown readable memory:", p2i(addr));
1178 for (address p = addr; p < align_up(addr + 1, sizeof(intptr_t)); ++p) {
1179 st->print(" %02x", *(u1*)p);
1180 }
1181 st->cr();
1182 return;
1183 }
1184
1185 st->print_cr(INTPTR_FORMAT " is an unknown value", p2i(addr));
1186 }
1187
1188 // Looks like all platforms can use the same function to check if C
1189 // stack is walkable beyond current frame. The check for fp() is not
1190 // necessary on Sparc, but it's harmless.
1191 bool os::is_first_C_frame(frame* fr) {
1192 // Load up sp, fp, sender sp and sender fp, check for reasonable values.
1193 // Check usp first, because if that's bad the other accessors may fault
1194 // on some architectures. Ditto ufp second, etc.
1195 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1);
1196 // sp on amd can be 32 bit aligned.
1197 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1);
1198
1199 uintptr_t usp = (uintptr_t)fr->sp();
1200 if ((usp & sp_align_mask) != 0) return true;
1201
1202 uintptr_t ufp = (uintptr_t)fr->fp();
1203 if ((ufp & fp_align_mask) != 0) return true;
1204
1205 uintptr_t old_sp = (uintptr_t)fr->sender_sp();
1206 if ((old_sp & sp_align_mask) != 0) return true;
1207 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true;
1208
1209 uintptr_t old_fp = (uintptr_t)fr->link();
1210 if ((old_fp & fp_align_mask) != 0) return true;
1211 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true;
1212
1213 // stack grows downwards; if old_fp is below current fp or if the stack
1214 // frame is too large, either the stack is corrupted or fp is not saved
1215 // on stack (i.e. on x86, ebp may be used as general register). The stack
1216 // is not walkable beyond current frame.
1217 if (old_fp < ufp) return true;
1218 if (old_fp - ufp > 64 * K) return true;
1219
1220 return false;
1221 }
1222
1223
1224 // Set up the boot classpath.
1225
1226 char* os::format_boot_path(const char* format_string,
1227 const char* home,
1228 int home_len,
1229 char fileSep,
1230 char pathSep) {
1231 assert((fileSep == '/' && pathSep == ':') ||
1232 (fileSep == '\\' && pathSep == ';'), "unexpected separator chars");
1233
1234 // Scan the format string to determine the length of the actual
1235 // boot classpath, and handle platform dependencies as well.
1236 int formatted_path_len = 0;
1237 const char* p;
1238 for (p = format_string; *p != 0; ++p) {
1239 if (*p == '%') formatted_path_len += home_len - 1;
1240 ++formatted_path_len;
1241 }
1242
1243 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal);
1244 if (formatted_path == NULL) {
1245 return NULL;
1246 }
1247
1248 // Create boot classpath from format, substituting separator chars and
1249 // java home directory.
1250 char* q = formatted_path;
1251 for (p = format_string; *p != 0; ++p) {
1252 switch (*p) {
1253 case '%':
1254 strcpy(q, home);
1255 q += home_len;
1256 break;
1257 case '/':
1258 *q++ = fileSep;
1259 break;
1260 case ':':
1261 *q++ = pathSep;
1262 break;
1263 default:
1264 *q++ = *p;
1265 }
1266 }
1267 *q = '\0';
1268
1269 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched");
1270 return formatted_path;
1271 }
1272
1273 // This function is a proxy to fopen, it tries to add a non standard flag ('e' or 'N')
1274 // that ensures automatic closing of the file on exec. If it can not find support in
1275 // the underlying c library, it will make an extra system call (fcntl) to ensure automatic
1276 // closing of the file on exec.
1277 FILE* os::fopen(const char* path, const char* mode) {
1278 char modified_mode[20];
1279 assert(strlen(mode) + 1 < sizeof(modified_mode), "mode chars plus one extra must fit in buffer");
1280 sprintf(modified_mode, "%s" LINUX_ONLY("e") BSD_ONLY("e") WINDOWS_ONLY("N"), mode);
1281 FILE* file = ::fopen(path, modified_mode);
1282
1283 #if !(defined LINUX || defined BSD || defined _WINDOWS)
1284 // assume fcntl FD_CLOEXEC support as a backup solution when 'e' or 'N'
1285 // is not supported as mode in fopen
1286 if (file != NULL) {
1287 int fd = fileno(file);
1288 if (fd != -1) {
1289 int fd_flags = fcntl(fd, F_GETFD);
1290 if (fd_flags != -1) {
1291 fcntl(fd, F_SETFD, fd_flags | FD_CLOEXEC);
1292 }
1293 }
1294 }
1295 #endif
1296
1297 return file;
1298 }
1299
1300 bool os::set_boot_path(char fileSep, char pathSep) {
1301 const char* home = Arguments::get_java_home();
1302 int home_len = (int)strlen(home);
1303
1304 struct stat st;
1305
1306 // modular image if "modules" jimage exists
1307 char* jimage = format_boot_path("%/lib/" MODULES_IMAGE_NAME, home, home_len, fileSep, pathSep);
1308 if (jimage == NULL) return false;
1309 bool has_jimage = (os::stat(jimage, &st) == 0);
1310 if (has_jimage) {
1311 Arguments::set_sysclasspath(jimage, true);
1312 FREE_C_HEAP_ARRAY(char, jimage);
1313 return true;
1314 }
1315 FREE_C_HEAP_ARRAY(char, jimage);
1316
1317 // check if developer build with exploded modules
1318 char* base_classes = format_boot_path("%/modules/" JAVA_BASE_NAME, home, home_len, fileSep, pathSep);
1319 if (base_classes == NULL) return false;
1320 if (os::stat(base_classes, &st) == 0) {
1321 Arguments::set_sysclasspath(base_classes, false);
1322 FREE_C_HEAP_ARRAY(char, base_classes);
1323 return true;
1324 }
1325 FREE_C_HEAP_ARRAY(char, base_classes);
1326
1327 return false;
1328 }
1329
1330 /*
1331 * Splits a path, based on its separator, the number of
1332 * elements is returned back in n.
1333 * It is the callers responsibility to:
1334 * a> check the value of n, and n may be 0.
1335 * b> ignore any empty path elements
1336 * c> free up the data.
1337 */
1338 char** os::split_path(const char* path, int* n) {
1339 *n = 0;
1340 if (path == NULL || strlen(path) == 0) {
1341 return NULL;
1342 }
1343 const char psepchar = *os::path_separator();
1344 char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal);
1345 if (inpath == NULL) {
1346 return NULL;
1347 }
1348 strcpy(inpath, path);
1349 int count = 1;
1350 char* p = strchr(inpath, psepchar);
1351 // Get a count of elements to allocate memory
1352 while (p != NULL) {
1353 count++;
1354 p++;
1355 p = strchr(p, psepchar);
1356 }
1357 char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count, mtInternal);
1358 if (opath == NULL) {
1359 return NULL;
1360 }
1361
1362 // do the actual splitting
1363 p = inpath;
1364 for (int i = 0 ; i < count ; i++) {
1365 size_t len = strcspn(p, os::path_separator());
1366 if (len > JVM_MAXPATHLEN) {
1367 return NULL;
1368 }
1369 // allocate the string and add terminator storage
1370 char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
1371 if (s == NULL) {
1372 return NULL;
1373 }
1374 strncpy(s, p, len);
1375 s[len] = '\0';
1376 opath[i] = s;
1377 p += len + 1;
1378 }
1379 FREE_C_HEAP_ARRAY(char, inpath);
1380 *n = count;
1381 return opath;
1382 }
1383
1384 // Returns true if the current stack pointer is above the stack shadow
1385 // pages, false otherwise.
1386 bool os::stack_shadow_pages_available(Thread *thread, const methodHandle& method, address sp) {
1387 if (!thread->is_Java_thread()) return false;
1388 // Check if we have StackShadowPages above the yellow zone. This parameter
1389 // is dependent on the depth of the maximum VM call stack possible from
1390 // the handler for stack overflow. 'instanceof' in the stack overflow
1391 // handler or a println uses at least 8k stack of VM and native code
1392 // respectively.
1393 const int framesize_in_bytes =
1394 Interpreter::size_top_interpreter_activation(method()) * wordSize;
1395
1396 address limit = ((JavaThread*)thread)->stack_end() +
1397 (JavaThread::stack_guard_zone_size() + JavaThread::stack_shadow_zone_size());
1398
1399 return sp > (limit + framesize_in_bytes);
1400 }
1401
1402 size_t os::page_size_for_region(size_t region_size, size_t min_pages, bool must_be_aligned) {
1403 assert(min_pages > 0, "sanity");
1404 if (UseLargePages) {
1405 const size_t max_page_size = region_size / min_pages;
1406
1407 for (size_t i = 0; _page_sizes[i] != 0; ++i) {
1408 const size_t page_size = _page_sizes[i];
1409 if (page_size <= max_page_size) {
1410 if (!must_be_aligned || is_aligned(region_size, page_size)) {
1411 return page_size;
1412 }
1413 }
1414 }
1415 }
1416
1417 return vm_page_size();
1418 }
1419
1420 size_t os::page_size_for_region_aligned(size_t region_size, size_t min_pages) {
1421 return page_size_for_region(region_size, min_pages, true);
1422 }
1423
1424 size_t os::page_size_for_region_unaligned(size_t region_size, size_t min_pages) {
1425 return page_size_for_region(region_size, min_pages, false);
1426 }
1427
1428 static const char* errno_to_string (int e, bool short_text) {
1429 #define ALL_SHARED_ENUMS(X) \
1430 X(E2BIG, "Argument list too long") \
1431 X(EACCES, "Permission denied") \
1432 X(EADDRINUSE, "Address in use") \
1433 X(EADDRNOTAVAIL, "Address not available") \
1434 X(EAFNOSUPPORT, "Address family not supported") \
1435 X(EAGAIN, "Resource unavailable, try again") \
1436 X(EALREADY, "Connection already in progress") \
1437 X(EBADF, "Bad file descriptor") \
1438 X(EBADMSG, "Bad message") \
1439 X(EBUSY, "Device or resource busy") \
1440 X(ECANCELED, "Operation canceled") \
1441 X(ECHILD, "No child processes") \
1442 X(ECONNABORTED, "Connection aborted") \
1443 X(ECONNREFUSED, "Connection refused") \
1444 X(ECONNRESET, "Connection reset") \
1445 X(EDEADLK, "Resource deadlock would occur") \
1446 X(EDESTADDRREQ, "Destination address required") \
1447 X(EDOM, "Mathematics argument out of domain of function") \
1448 X(EEXIST, "File exists") \
1449 X(EFAULT, "Bad address") \
1450 X(EFBIG, "File too large") \
1451 X(EHOSTUNREACH, "Host is unreachable") \
1452 X(EIDRM, "Identifier removed") \
1453 X(EILSEQ, "Illegal byte sequence") \
1454 X(EINPROGRESS, "Operation in progress") \
1455 X(EINTR, "Interrupted function") \
1456 X(EINVAL, "Invalid argument") \
1457 X(EIO, "I/O error") \
1458 X(EISCONN, "Socket is connected") \
1459 X(EISDIR, "Is a directory") \
1460 X(ELOOP, "Too many levels of symbolic links") \
1461 X(EMFILE, "Too many open files") \
1462 X(EMLINK, "Too many links") \
1463 X(EMSGSIZE, "Message too large") \
1464 X(ENAMETOOLONG, "Filename too long") \
1465 X(ENETDOWN, "Network is down") \
1466 X(ENETRESET, "Connection aborted by network") \
1467 X(ENETUNREACH, "Network unreachable") \
1468 X(ENFILE, "Too many files open in system") \
1469 X(ENOBUFS, "No buffer space available") \
1470 X(ENODATA, "No message is available on the STREAM head read queue") \
1471 X(ENODEV, "No such device") \
1472 X(ENOENT, "No such file or directory") \
1473 X(ENOEXEC, "Executable file format error") \
1474 X(ENOLCK, "No locks available") \
1475 X(ENOLINK, "Reserved") \
1476 X(ENOMEM, "Not enough space") \
1477 X(ENOMSG, "No message of the desired type") \
1478 X(ENOPROTOOPT, "Protocol not available") \
1479 X(ENOSPC, "No space left on device") \
1480 X(ENOSR, "No STREAM resources") \
1481 X(ENOSTR, "Not a STREAM") \
1482 X(ENOSYS, "Function not supported") \
1483 X(ENOTCONN, "The socket is not connected") \
1484 X(ENOTDIR, "Not a directory") \
1485 X(ENOTEMPTY, "Directory not empty") \
1486 X(ENOTSOCK, "Not a socket") \
1487 X(ENOTSUP, "Not supported") \
1488 X(ENOTTY, "Inappropriate I/O control operation") \
1489 X(ENXIO, "No such device or address") \
1490 X(EOPNOTSUPP, "Operation not supported on socket") \
1491 X(EOVERFLOW, "Value too large to be stored in data type") \
1492 X(EPERM, "Operation not permitted") \
1493 X(EPIPE, "Broken pipe") \
1494 X(EPROTO, "Protocol error") \
1495 X(EPROTONOSUPPORT, "Protocol not supported") \
1496 X(EPROTOTYPE, "Protocol wrong type for socket") \
1497 X(ERANGE, "Result too large") \
1498 X(EROFS, "Read-only file system") \
1499 X(ESPIPE, "Invalid seek") \
1500 X(ESRCH, "No such process") \
1501 X(ETIME, "Stream ioctl() timeout") \
1502 X(ETIMEDOUT, "Connection timed out") \
1503 X(ETXTBSY, "Text file busy") \
1504 X(EWOULDBLOCK, "Operation would block") \
1505 X(EXDEV, "Cross-device link")
1506
1507 #define DEFINE_ENTRY(e, text) { e, #e, text },
1508
1509 static const struct {
1510 int v;
1511 const char* short_text;
1512 const char* long_text;
1513 } table [] = {
1514
1515 ALL_SHARED_ENUMS(DEFINE_ENTRY)
1516
1517 // The following enums are not defined on all platforms.
1518 #ifdef ESTALE
1519 DEFINE_ENTRY(ESTALE, "Reserved")
1520 #endif
1521 #ifdef EDQUOT
1522 DEFINE_ENTRY(EDQUOT, "Reserved")
1523 #endif
1524 #ifdef EMULTIHOP
1525 DEFINE_ENTRY(EMULTIHOP, "Reserved")
1526 #endif
1527
1528 // End marker.
1529 { -1, "Unknown errno", "Unknown error" }
1530
1531 };
1532
1533 #undef DEFINE_ENTRY
1534 #undef ALL_FLAGS
1535
1536 int i = 0;
1537 while (table[i].v != -1 && table[i].v != e) {
1538 i ++;
1539 }
1540
1541 return short_text ? table[i].short_text : table[i].long_text;
1542
1543 }
1544
1545 const char* os::strerror(int e) {
1546 return errno_to_string(e, false);
1547 }
1548
1549 const char* os::errno_name(int e) {
1550 return errno_to_string(e, true);
1551 }
1552
1553 void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count) {
1554 LogTarget(Info, pagesize) log;
1555 if (log.is_enabled()) {
1556 LogStream out(log);
1557
1558 out.print("%s: ", str);
1559 for (int i = 0; i < count; ++i) {
1560 out.print(" " SIZE_FORMAT, page_sizes[i]);
1561 }
1562 out.cr();
1563 }
1564 }
1565
1566 #define trace_page_size_params(size) byte_size_in_exact_unit(size), exact_unit_for_byte_size(size)
1567
1568 void os::trace_page_sizes(const char* str,
1569 const size_t region_min_size,
1570 const size_t region_max_size,
1571 const size_t page_size,
1572 const char* base,
1573 const size_t size) {
1574
1575 log_info(pagesize)("%s: "
1576 " min=" SIZE_FORMAT "%s"
1577 " max=" SIZE_FORMAT "%s"
1578 " base=" PTR_FORMAT
1579 " page_size=" SIZE_FORMAT "%s"
1580 " size=" SIZE_FORMAT "%s",
1581 str,
1582 trace_page_size_params(region_min_size),
1583 trace_page_size_params(region_max_size),
1584 p2i(base),
1585 trace_page_size_params(page_size),
1586 trace_page_size_params(size));
1587 }
1588
1589 void os::trace_page_sizes_for_requested_size(const char* str,
1590 const size_t requested_size,
1591 const size_t page_size,
1592 const size_t alignment,
1593 const char* base,
1594 const size_t size) {
1595
1596 log_info(pagesize)("%s:"
1597 " req_size=" SIZE_FORMAT "%s"
1598 " base=" PTR_FORMAT
1599 " page_size=" SIZE_FORMAT "%s"
1600 " alignment=" SIZE_FORMAT "%s"
1601 " size=" SIZE_FORMAT "%s",
1602 str,
1603 trace_page_size_params(requested_size),
1604 p2i(base),
1605 trace_page_size_params(page_size),
1606 trace_page_size_params(alignment),
1607 trace_page_size_params(size));
1608 }
1609
1610
1611 // This is the working definition of a server class machine:
1612 // >= 2 physical CPU's and >=2GB of memory, with some fuzz
1613 // because the graphics memory (?) sometimes masks physical memory.
1614 // If you want to change the definition of a server class machine
1615 // on some OS or platform, e.g., >=4GB on Windows platforms,
1616 // then you'll have to parameterize this method based on that state,
1617 // as was done for logical processors here, or replicate and
1618 // specialize this method for each platform. (Or fix os to have
1619 // some inheritance structure and use subclassing. Sigh.)
1620 // If you want some platform to always or never behave as a server
1621 // class machine, change the setting of AlwaysActAsServerClassMachine
1622 // and NeverActAsServerClassMachine in globals*.hpp.
1623 bool os::is_server_class_machine() {
1624 // First check for the early returns
1625 if (NeverActAsServerClassMachine) {
1626 return false;
1627 }
1628 if (AlwaysActAsServerClassMachine) {
1629 return true;
1630 }
1631 // Then actually look at the machine
1632 bool result = false;
1633 const unsigned int server_processors = 2;
1634 const julong server_memory = 2UL * G;
1635 // We seem not to get our full complement of memory.
1636 // We allow some part (1/8?) of the memory to be "missing",
1637 // based on the sizes of DIMMs, and maybe graphics cards.
1638 const julong missing_memory = 256UL * M;
1639
1640 /* Is this a server class machine? */
1641 if ((os::active_processor_count() >= (int)server_processors) &&
1642 (os::physical_memory() >= (server_memory - missing_memory))) {
1643 const unsigned int logical_processors =
1644 VM_Version::logical_processors_per_package();
1645 if (logical_processors > 1) {
1646 const unsigned int physical_packages =
1647 os::active_processor_count() / logical_processors;
1648 if (physical_packages >= server_processors) {
1649 result = true;
1650 }
1651 } else {
1652 result = true;
1653 }
1654 }
1655 return result;
1656 }
1657
1658 void os::initialize_initial_active_processor_count() {
1659 assert(_initial_active_processor_count == 0, "Initial active processor count already set.");
1660 _initial_active_processor_count = active_processor_count();
1661 log_debug(os)("Initial active processor count set to %d" , _initial_active_processor_count);
1662 }
1663
1664 void os::SuspendedThreadTask::run() {
1665 internal_do_task();
1666 _done = true;
1667 }
1668
1669 bool os::create_stack_guard_pages(char* addr, size_t bytes) {
1670 return os::pd_create_stack_guard_pages(addr, bytes);
1671 }
1672
1673 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint, int file_desc) {
1674 char* result = NULL;
1675
1676 if (file_desc != -1) {
1677 // Could have called pd_reserve_memory() followed by replace_existing_mapping_with_file_mapping(),
1678 // but AIX may use SHM in which case its more trouble to detach the segment and remap memory to the file.
1679 result = os::map_memory_to_file(addr, bytes, file_desc);
1680 if (result != NULL) {
1681 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC);
1682 }
1683 } else {
1684 result = pd_reserve_memory(bytes, addr, alignment_hint);
1685 if (result != NULL) {
1686 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1687 }
1688 }
1689
1690 return result;
1691 }
1692
1693 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint,
1694 MEMFLAGS flags) {
1695 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1696 if (result != NULL) {
1697 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1698 MemTracker::record_virtual_memory_type((address)result, flags);
1699 }
1700
1701 return result;
1702 }
1703
1704 char* os::attempt_reserve_memory_at(size_t bytes, char* addr, int file_desc) {
1705 char* result = NULL;
1706 if (file_desc != -1) {
1707 result = pd_attempt_reserve_memory_at(bytes, addr, file_desc);
1708 if (result != NULL) {
1709 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC);
1710 }
1711 } else {
1712 result = pd_attempt_reserve_memory_at(bytes, addr);
1713 if (result != NULL) {
1714 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1715 }
1716 }
1717 return result;
1718 }
1719
1720 void os::split_reserved_memory(char *base, size_t size,
1721 size_t split, bool realloc) {
1722 pd_split_reserved_memory(base, size, split, realloc);
1723 }
1724
1725 bool os::commit_memory(char* addr, size_t bytes, bool executable) {
1726 bool res = pd_commit_memory(addr, bytes, executable);
1727 if (res) {
1728 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1729 }
1730 return res;
1731 }
1732
1733 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint,
1734 bool executable) {
1735 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable);
1736 if (res) {
1737 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1738 }
1739 return res;
1740 }
1741
1742 void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable,
1743 const char* mesg) {
1744 pd_commit_memory_or_exit(addr, bytes, executable, mesg);
1745 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1746 }
1747
1748 void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint,
1749 bool executable, const char* mesg) {
1750 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg);
1751 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1752 }
1753
1754 bool os::uncommit_memory(char* addr, size_t bytes) {
1755 bool res;
1756 if (MemTracker::tracking_level() > NMT_minimal) {
1757 Tracker tkr(Tracker::uncommit);
1758 res = pd_uncommit_memory(addr, bytes);
1759 if (res) {
1760 tkr.record((address)addr, bytes);
1761 }
1762 } else {
1763 res = pd_uncommit_memory(addr, bytes);
1764 }
1765 return res;
1766 }
1767
1768 bool os::release_memory(char* addr, size_t bytes) {
1769 bool res;
1770 if (MemTracker::tracking_level() > NMT_minimal) {
1771 Tracker tkr(Tracker::release);
1772 res = pd_release_memory(addr, bytes);
1773 if (res) {
1774 tkr.record((address)addr, bytes);
1775 }
1776 } else {
1777 res = pd_release_memory(addr, bytes);
1778 }
1779 return res;
1780 }
1781
1782 void os::pretouch_memory(void* start, void* end, size_t page_size) {
1783 for (volatile char *p = (char*)start; p < (char*)end; p += page_size) {
1784 *p = 0;
1785 }
1786 }
1787
1788 char* os::map_memory(int fd, const char* file_name, size_t file_offset,
1789 char *addr, size_t bytes, bool read_only,
1790 bool allow_exec) {
1791 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec);
1792 if (result != NULL) {
1793 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC);
1794 }
1795 return result;
1796 }
1797
1798 char* os::remap_memory(int fd, const char* file_name, size_t file_offset,
1799 char *addr, size_t bytes, bool read_only,
1800 bool allow_exec) {
1801 return pd_remap_memory(fd, file_name, file_offset, addr, bytes,
1802 read_only, allow_exec);
1803 }
1804
1805 bool os::unmap_memory(char *addr, size_t bytes) {
1806 bool result;
1807 if (MemTracker::tracking_level() > NMT_minimal) {
1808 Tracker tkr(Tracker::release);
1809 result = pd_unmap_memory(addr, bytes);
1810 if (result) {
1811 tkr.record((address)addr, bytes);
1812 }
1813 } else {
1814 result = pd_unmap_memory(addr, bytes);
1815 }
1816 return result;
1817 }
1818
1819 void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) {
1820 pd_free_memory(addr, bytes, alignment_hint);
1821 }
1822
1823 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
1824 pd_realign_memory(addr, bytes, alignment_hint);
1825 }
1826
1827 #ifndef _WINDOWS
1828 /* try to switch state from state "from" to state "to"
1829 * returns the state set after the method is complete
1830 */
1831 os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from,
1832 os::SuspendResume::State to)
1833 {
1834 os::SuspendResume::State result = Atomic::cmpxchg(to, &_state, from);
1835 if (result == from) {
1836 // success
1837 return to;
1838 }
1839 return result;
1840 }
1841 #endif