1 /*
2 * Copyright (c) 1997, 2018, 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/vmGCOperations.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 #ifdef ASSERT
42 #include "memory/guardedMemory.hpp"
43 #endif
44 #include "memory/resourceArea.hpp"
45 #include "oops/oop.inline.hpp"
46 #include "prims/jvm_misc.hpp"
47 #include "prims/privilegedStack.hpp"
48 #include "runtime/arguments.hpp"
49 #include "runtime/atomic.hpp"
50 #include "runtime/frame.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 #include "utilities/vmErrorHelper.hpp"
70
71 # include <signal.h>
72 # include <errno.h>
73
74 OSThread* os::_starting_thread = NULL;
75 address os::_polling_page = NULL;
76 volatile int32_t* os::_mem_serialize_page = NULL;
77 uintptr_t os::_serialize_page_mask = 0;
78 volatile unsigned int os::_rand_seed = 1;
79 int os::_processor_count = 0;
80 int os::_initial_active_processor_count = 0;
81 size_t os::_page_sizes[os::page_sizes_max];
82
83 #ifndef PRODUCT
84 julong os::num_mallocs = 0; // # of calls to malloc/realloc
85 julong os::alloc_bytes = 0; // # of bytes allocated
86 julong os::num_frees = 0; // # of calls to free
87 julong os::free_bytes = 0; // # of bytes freed
88 #endif
89
90 static size_t cur_malloc_words = 0; // current size for MallocMaxTestWords
91
92 void os_init_globals() {
93 // Called from init_globals().
94 // See Threads::create_vm() in thread.cpp, and init.cpp.
95 os::init_globals();
96 }
97
98 static time_t get_timezone(const struct tm* time_struct) {
99 #if defined(_ALLBSD_SOURCE)
100 return time_struct->tm_gmtoff;
101 #elif defined(_WINDOWS)
102 long zone;
103 _get_timezone(&zone);
104 return static_cast<time_t>(zone);
105 #else
106 return timezone;
107 #endif
108 }
109
110 int os::snprintf(char* buf, size_t len, const char* fmt, ...) {
111 va_list args;
112 va_start(args, fmt);
113 int result = os::vsnprintf(buf, len, fmt, args);
114 va_end(args);
115 return result;
116 }
117
118 // Fill in buffer with current local time as an ISO-8601 string.
119 // E.g., yyyy-mm-ddThh:mm:ss-zzzz.
120 // Returns buffer, or NULL if it failed.
121 // This would mostly be a call to
122 // strftime(...., "%Y-%m-%d" "T" "%H:%M:%S" "%z", ....)
123 // except that on Windows the %z behaves badly, so we do it ourselves.
124 // Also, people wanted milliseconds on there,
125 // and strftime doesn't do milliseconds.
126 char* os::iso8601_time(char* buffer, size_t buffer_length, bool utc) {
127 // Output will be of the form "YYYY-MM-DDThh:mm:ss.mmm+zzzz\0"
128 // 1 2
129 // 12345678901234567890123456789
130 // format string: "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d"
131 static const size_t needed_buffer = 29;
132
133 // Sanity check the arguments
134 if (buffer == NULL) {
135 assert(false, "NULL buffer");
136 return NULL;
137 }
138 if (buffer_length < needed_buffer) {
139 assert(false, "buffer_length too small");
140 return NULL;
141 }
142 // Get the current time
143 jlong milliseconds_since_19700101 = javaTimeMillis();
144 const int milliseconds_per_microsecond = 1000;
145 const time_t seconds_since_19700101 =
146 milliseconds_since_19700101 / milliseconds_per_microsecond;
147 const int milliseconds_after_second =
148 milliseconds_since_19700101 % milliseconds_per_microsecond;
149 // Convert the time value to a tm and timezone variable
150 struct tm time_struct;
151 if (utc) {
152 if (gmtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
153 assert(false, "Failed gmtime_pd");
154 return NULL;
155 }
156 } else {
157 if (localtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
158 assert(false, "Failed localtime_pd");
159 return NULL;
160 }
161 }
162 const time_t zone = get_timezone(&time_struct);
163
164 // If daylight savings time is in effect,
165 // we are 1 hour East of our time zone
166 const time_t seconds_per_minute = 60;
167 const time_t minutes_per_hour = 60;
168 const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour;
169 time_t UTC_to_local = zone;
170 if (time_struct.tm_isdst > 0) {
171 UTC_to_local = UTC_to_local - seconds_per_hour;
172 }
173
174 // No offset when dealing with UTC
175 if (utc) {
176 UTC_to_local = 0;
177 }
178
179 // Compute the time zone offset.
180 // localtime_pd() sets timezone to the difference (in seconds)
181 // between UTC and and local time.
182 // ISO 8601 says we need the difference between local time and UTC,
183 // we change the sign of the localtime_pd() result.
184 const time_t local_to_UTC = -(UTC_to_local);
185 // Then we have to figure out if if we are ahead (+) or behind (-) UTC.
186 char sign_local_to_UTC = '+';
187 time_t abs_local_to_UTC = local_to_UTC;
188 if (local_to_UTC < 0) {
189 sign_local_to_UTC = '-';
190 abs_local_to_UTC = -(abs_local_to_UTC);
191 }
192 // Convert time zone offset seconds to hours and minutes.
193 const time_t zone_hours = (abs_local_to_UTC / seconds_per_hour);
194 const time_t zone_min =
195 ((abs_local_to_UTC % seconds_per_hour) / seconds_per_minute);
196
197 // Print an ISO 8601 date and time stamp into the buffer
198 const int year = 1900 + time_struct.tm_year;
199 const int month = 1 + time_struct.tm_mon;
200 const int printed = jio_snprintf(buffer, buffer_length,
201 "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d",
202 year,
203 month,
204 time_struct.tm_mday,
205 time_struct.tm_hour,
206 time_struct.tm_min,
207 time_struct.tm_sec,
208 milliseconds_after_second,
209 sign_local_to_UTC,
210 zone_hours,
211 zone_min);
212 if (printed == 0) {
213 assert(false, "Failed jio_printf");
214 return NULL;
215 }
216 return buffer;
217 }
218
219 OSReturn os::set_priority(Thread* thread, ThreadPriority p) {
220 debug_only(Thread::check_for_dangling_thread_pointer(thread);)
221
222 if (p >= MinPriority && p <= MaxPriority) {
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 && AttachListener::is_init_trigger()) {
366 continue;
367 }
368 // Print stack traces
369 // Any SIGBREAK operations added here should make sure to flush
370 // the output stream (e.g. tty->flush()) after output. See 4803766.
371 // Each module also prints an extra carriage return after its output.
372 VM_PrintThreads op;
373 VMThread::execute(&op);
374 VM_PrintJNI jni_op;
375 VMThread::execute(&jni_op);
376 VM_FindDeadlocks op1(tty);
377 VMThread::execute(&op1);
378 Universe::print_heap_at_SIGBREAK();
379 if (PrintClassHistogram) {
380 VM_GC_HeapInspection op1(tty, true /* force full GC before heap inspection */);
381 VMThread::execute(&op1);
382 }
383 if (JvmtiExport::should_post_data_dump()) {
384 JvmtiExport::post_data_dump();
385 }
386 break;
387 }
388 default: {
389 // Dispatch the signal to java
390 HandleMark hm(THREAD);
391 Klass* klass = SystemDictionary::resolve_or_null(vmSymbols::jdk_internal_misc_Signal(), THREAD);
392 if (klass != NULL) {
393 JavaValue result(T_VOID);
394 JavaCallArguments args;
395 args.push_int(sig);
396 JavaCalls::call_static(
397 &result,
398 klass,
399 vmSymbols::dispatch_name(),
400 vmSymbols::int_void_signature(),
401 &args,
402 THREAD
403 );
404 }
405 if (HAS_PENDING_EXCEPTION) {
406 // tty is initialized early so we don't expect it to be null, but
407 // if it is we can't risk doing an initialization that might
408 // trigger additional out-of-memory conditions
409 if (tty != NULL) {
410 char klass_name[256];
411 char tmp_sig_name[16];
412 const char* sig_name = "UNKNOWN";
413 InstanceKlass::cast(PENDING_EXCEPTION->klass())->
414 name()->as_klass_external_name(klass_name, 256);
415 if (os::exception_name(sig, tmp_sig_name, 16) != NULL)
416 sig_name = tmp_sig_name;
417 warning("Exception %s occurred dispatching signal %s to handler"
418 "- the VM may need to be forcibly terminated",
419 klass_name, sig_name );
420 }
421 CLEAR_PENDING_EXCEPTION;
422 }
423 }
424 }
425 }
426 }
427
428 void os::init_before_ergo() {
429 initialize_initial_active_processor_count();
430 // We need to initialize large page support here because ergonomics takes some
431 // decisions depending on large page support and the calculated large page size.
432 large_page_init();
433
434 // We need to adapt the configured number of stack protection pages given
435 // in 4K pages to the actual os page size. We must do this before setting
436 // up minimal stack sizes etc. in os::init_2().
437 JavaThread::set_stack_red_zone_size (align_up(StackRedPages * 4 * K, vm_page_size()));
438 JavaThread::set_stack_yellow_zone_size (align_up(StackYellowPages * 4 * K, vm_page_size()));
439 JavaThread::set_stack_reserved_zone_size(align_up(StackReservedPages * 4 * K, vm_page_size()));
440 JavaThread::set_stack_shadow_zone_size (align_up(StackShadowPages * 4 * K, vm_page_size()));
441
442 // VM version initialization identifies some characteristics of the
443 // platform that are used during ergonomic decisions.
444 VM_Version::init_before_ergo();
445 }
446
447 void os::initialize_jdk_signal_support(TRAPS) {
448 if (!ReduceSignalUsage) {
449 // Setup JavaThread for processing signals
450 const char thread_name[] = "Signal Dispatcher";
451 Handle string = java_lang_String::create_from_str(thread_name, CHECK);
452
453 // Initialize thread_oop to put it into the system threadGroup
454 Handle thread_group (THREAD, Universe::system_thread_group());
455 Handle thread_oop = JavaCalls::construct_new_instance(SystemDictionary::Thread_klass(),
456 vmSymbols::threadgroup_string_void_signature(),
457 thread_group,
458 string,
459 CHECK);
460
461 Klass* group = SystemDictionary::ThreadGroup_klass();
462 JavaValue result(T_VOID);
463 JavaCalls::call_special(&result,
464 thread_group,
465 group,
466 vmSymbols::add_method_name(),
467 vmSymbols::thread_void_signature(),
468 thread_oop,
469 CHECK);
470
471 { MutexLocker mu(Threads_lock);
472 JavaThread* signal_thread = new JavaThread(&signal_thread_entry);
473
474 // At this point it may be possible that no osthread was created for the
475 // JavaThread due to lack of memory. We would have to throw an exception
476 // in that case. However, since this must work and we do not allow
477 // exceptions anyway, check and abort if this fails.
478 if (signal_thread == NULL || signal_thread->osthread() == NULL) {
479 vm_exit_during_initialization("java.lang.OutOfMemoryError",
480 os::native_thread_creation_failed_msg());
481 }
482
483 java_lang_Thread::set_thread(thread_oop(), signal_thread);
484 java_lang_Thread::set_priority(thread_oop(), NearMaxPriority);
485 java_lang_Thread::set_daemon(thread_oop());
486
487 signal_thread->set_threadObj(thread_oop());
488 Threads::add(signal_thread);
489 Thread::start(signal_thread);
490 }
491 // Handle ^BREAK
492 os::signal(SIGBREAK, os::user_handler());
493 }
494 }
495
496
497 void os::terminate_signal_thread() {
498 if (!ReduceSignalUsage)
499 signal_notify(sigexitnum_pd());
500 }
501
502
503 // --------------------- loading libraries ---------------------
504
505 typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *);
506 extern struct JavaVM_ main_vm;
507
508 static void* _native_java_library = NULL;
509
510 void* os::native_java_library() {
511 if (_native_java_library == NULL) {
512 char buffer[JVM_MAXPATHLEN];
513 char ebuf[1024];
514
515 // Try to load verify dll first. In 1.3 java dll depends on it and is not
516 // always able to find it when the loading executable is outside the JDK.
517 // In order to keep working with 1.2 we ignore any loading errors.
518 if (dll_locate_lib(buffer, sizeof(buffer), Arguments::get_dll_dir(),
519 "verify")) {
520 dll_load(buffer, ebuf, sizeof(ebuf));
521 }
522
523 // Load java dll
524 if (dll_locate_lib(buffer, sizeof(buffer), Arguments::get_dll_dir(),
525 "java")) {
526 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf));
527 }
528 if (_native_java_library == NULL) {
529 vm_exit_during_initialization("Unable to load native library", ebuf);
530 }
531
532 #if defined(__OpenBSD__)
533 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so
534 // ignore errors
535 if (dll_locate_lib(buffer, sizeof(buffer), Arguments::get_dll_dir(),
536 "net")) {
537 dll_load(buffer, ebuf, sizeof(ebuf));
538 }
539 #endif
540 }
541 return _native_java_library;
542 }
543
544 /*
545 * Support for finding Agent_On(Un)Load/Attach<_lib_name> if it exists.
546 * If check_lib == true then we are looking for an
547 * Agent_OnLoad_lib_name or Agent_OnAttach_lib_name function to determine if
548 * this library is statically linked into the image.
549 * If check_lib == false then we will look for the appropriate symbol in the
550 * executable if agent_lib->is_static_lib() == true or in the shared library
551 * referenced by 'handle'.
552 */
553 void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib,
554 const char *syms[], size_t syms_len) {
555 assert(agent_lib != NULL, "sanity check");
556 const char *lib_name;
557 void *handle = agent_lib->os_lib();
558 void *entryName = NULL;
559 char *agent_function_name;
560 size_t i;
561
562 // If checking then use the agent name otherwise test is_static_lib() to
563 // see how to process this lookup
564 lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL);
565 for (i = 0; i < syms_len; i++) {
566 agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path());
567 if (agent_function_name == NULL) {
568 break;
569 }
570 entryName = dll_lookup(handle, agent_function_name);
571 FREE_C_HEAP_ARRAY(char, agent_function_name);
572 if (entryName != NULL) {
573 break;
574 }
575 }
576 return entryName;
577 }
578
579 // See if the passed in agent is statically linked into the VM image.
580 bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
581 size_t syms_len) {
582 void *ret;
583 void *proc_handle;
584 void *save_handle;
585
586 assert(agent_lib != NULL, "sanity check");
587 if (agent_lib->name() == NULL) {
588 return false;
589 }
590 proc_handle = get_default_process_handle();
591 // Check for Agent_OnLoad/Attach_lib_name function
592 save_handle = agent_lib->os_lib();
593 // We want to look in this process' symbol table.
594 agent_lib->set_os_lib(proc_handle);
595 ret = find_agent_function(agent_lib, true, syms, syms_len);
596 if (ret != NULL) {
597 // Found an entry point like Agent_OnLoad_lib_name so we have a static agent
598 agent_lib->set_valid();
599 agent_lib->set_static_lib(true);
600 return true;
601 }
602 agent_lib->set_os_lib(save_handle);
603 return false;
604 }
605
606 // --------------------- heap allocation utilities ---------------------
607
608 char *os::strdup(const char *str, MEMFLAGS flags) {
609 size_t size = strlen(str);
610 char *dup_str = (char *)malloc(size + 1, flags);
611 if (dup_str == NULL) return NULL;
612 strcpy(dup_str, str);
613 return dup_str;
614 }
615
616 char* os::strdup_check_oom(const char* str, MEMFLAGS flags) {
617 char* p = os::strdup(str, flags);
618 if (p == NULL) {
619 vm_exit_out_of_memory(strlen(str) + 1, OOM_MALLOC_ERROR, "os::strdup_check_oom");
620 }
621 return p;
622 }
623
624
625 #define paranoid 0 /* only set to 1 if you suspect checking code has bug */
626
627 #ifdef ASSERT
628
629 static void verify_memory(void* ptr) {
630 GuardedMemory guarded(ptr);
631 if (!guarded.verify_guards()) {
632 LogTarget(Warning, malloc, free) lt;
633 ResourceMark rm;
634 LogStream ls(lt);
635 ls.print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees);
636 ls.print_cr("## memory stomp:");
637 guarded.print_on(&ls);
638 fatal("memory stomping error");
639 }
640 }
641
642 #endif
643
644 //
645 // This function supports testing of the malloc out of memory
646 // condition without really running the system out of memory.
647 //
648 static bool has_reached_max_malloc_test_peak(size_t alloc_size) {
649 if (MallocMaxTestWords > 0) {
650 size_t words = (alloc_size / BytesPerWord);
651
652 if ((cur_malloc_words + words) > MallocMaxTestWords) {
653 return true;
654 }
655 Atomic::add(words, &cur_malloc_words);
656 }
657 return false;
658 }
659
660 void* os::malloc(size_t size, MEMFLAGS flags) {
661 return os::malloc(size, flags, CALLER_PC);
662 }
663
664 void* os::malloc(size_t size, MEMFLAGS memflags, const NativeCallStack& stack) {
665 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
666 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
667
668 // Since os::malloc can be called when the libjvm.{dll,so} is
669 // first loaded and we don't have a thread yet we must accept NULL also here.
670 assert(!os::ThreadCrashProtection::is_crash_protected(Thread::current_or_null()),
671 "malloc() not allowed when crash protection is set");
672
673 if (size == 0) {
674 // return a valid pointer if size is zero
675 // if NULL is returned the calling functions assume out of memory.
676 size = 1;
677 }
678
679 // NMT support
680 NMT_TrackingLevel level = MemTracker::tracking_level();
681 size_t nmt_header_size = MemTracker::malloc_header_size(level);
682
683 #ifndef ASSERT
684 const size_t alloc_size = size + nmt_header_size;
685 #else
686 const size_t alloc_size = GuardedMemory::get_total_size(size + nmt_header_size);
687 if (size + nmt_header_size > alloc_size) { // Check for rollover.
688 return NULL;
689 }
690 #endif
691
692 // For the test flag -XX:MallocMaxTestWords
693 if (has_reached_max_malloc_test_peak(size)) {
694 return NULL;
695 }
696
697 u_char* ptr;
698 ptr = (u_char*)::malloc(alloc_size);
699
700 #ifdef ASSERT
701 if (ptr == NULL) {
702 return NULL;
703 }
704 // Wrap memory with guard
705 GuardedMemory guarded(ptr, size + nmt_header_size);
706 ptr = guarded.get_user_ptr();
707 #endif
708 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) {
709 log_warning(malloc, free)("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr));
710 breakpoint();
711 }
712 debug_only(if (paranoid) verify_memory(ptr));
713
714 // we do not track guard memory
715 return MemTracker::record_malloc((address)ptr, size, memflags, stack, level);
716 }
717
718 void* os::realloc(void *memblock, size_t size, MEMFLAGS flags) {
719 return os::realloc(memblock, size, flags, CALLER_PC);
720 }
721
722 void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, const NativeCallStack& stack) {
723
724 // For the test flag -XX:MallocMaxTestWords
725 if (has_reached_max_malloc_test_peak(size)) {
726 return NULL;
727 }
728
729 if (size == 0) {
730 // return a valid pointer if size is zero
731 // if NULL is returned the calling functions assume out of memory.
732 size = 1;
733 }
734
735 #ifndef ASSERT
736 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
737 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
738 // NMT support
739 void* membase = MemTracker::record_free(memblock);
740 NMT_TrackingLevel level = MemTracker::tracking_level();
741 size_t nmt_header_size = MemTracker::malloc_header_size(level);
742 void* ptr = ::realloc(membase, size + nmt_header_size);
743 return MemTracker::record_malloc(ptr, size, memflags, stack, level);
744 #else
745 if (memblock == NULL) {
746 return os::malloc(size, memflags, stack);
747 }
748 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
749 log_warning(malloc, free)("os::realloc caught " PTR_FORMAT, p2i(memblock));
750 breakpoint();
751 }
752 // NMT support
753 void* membase = MemTracker::malloc_base(memblock);
754 verify_memory(membase);
755 // always move the block
756 void* ptr = os::malloc(size, memflags, stack);
757 // Copy to new memory if malloc didn't fail
758 if (ptr != NULL ) {
759 GuardedMemory guarded(MemTracker::malloc_base(memblock));
760 // Guard's user data contains NMT header
761 size_t memblock_size = guarded.get_user_size() - MemTracker::malloc_header_size(memblock);
762 memcpy(ptr, memblock, MIN2(size, memblock_size));
763 if (paranoid) verify_memory(MemTracker::malloc_base(ptr));
764 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) {
765 log_warning(malloc, free)("os::realloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr));
766 breakpoint();
767 }
768 os::free(memblock);
769 }
770 return ptr;
771 #endif
772 }
773
774
775 void os::free(void *memblock) {
776 NOT_PRODUCT(inc_stat_counter(&num_frees, 1));
777 #ifdef ASSERT
778 if (memblock == NULL) return;
779 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
780 log_warning(malloc, free)("os::free caught " PTR_FORMAT, p2i(memblock));
781 breakpoint();
782 }
783 void* membase = MemTracker::record_free(memblock);
784 verify_memory(membase);
785
786 GuardedMemory guarded(membase);
787 size_t size = guarded.get_user_size();
788 inc_stat_counter(&free_bytes, size);
789 membase = guarded.release_for_freeing();
790 ::free(membase);
791 #else
792 void* membase = MemTracker::record_free(memblock);
793 ::free(membase);
794 #endif
795 }
796
797 void os::init_random(unsigned int initval) {
798 _rand_seed = initval;
799 }
800
801
802 static int random_helper(unsigned int rand_seed) {
803 /* standard, well-known linear congruential random generator with
804 * next_rand = (16807*seed) mod (2**31-1)
805 * see
806 * (1) "Random Number Generators: Good Ones Are Hard to Find",
807 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988),
808 * (2) "Two Fast Implementations of the 'Minimal Standard' Random
809 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88.
810 */
811 const unsigned int a = 16807;
812 const unsigned int m = 2147483647;
813 const int q = m / a; assert(q == 127773, "weird math");
814 const int r = m % a; assert(r == 2836, "weird math");
815
816 // compute az=2^31p+q
817 unsigned int lo = a * (rand_seed & 0xFFFF);
818 unsigned int hi = a * (rand_seed >> 16);
819 lo += (hi & 0x7FFF) << 16;
820
821 // if q overflowed, ignore the overflow and increment q
822 if (lo > m) {
823 lo &= m;
824 ++lo;
825 }
826 lo += hi >> 15;
827
828 // if (p+q) overflowed, ignore the overflow and increment (p+q)
829 if (lo > m) {
830 lo &= m;
831 ++lo;
832 }
833 return lo;
834 }
835
836 int os::random() {
837 // Make updating the random seed thread safe.
838 while (true) {
839 unsigned int seed = _rand_seed;
840 unsigned int rand = random_helper(seed);
841 if (Atomic::cmpxchg(rand, &_rand_seed, seed) == seed) {
842 return static_cast<int>(rand);
843 }
844 }
845 }
846
847 // The INITIALIZED state is distinguished from the SUSPENDED state because the
848 // conditions in which a thread is first started are different from those in which
849 // a suspension is resumed. These differences make it hard for us to apply the
850 // tougher checks when starting threads that we want to do when resuming them.
851 // However, when start_thread is called as a result of Thread.start, on a Java
852 // thread, the operation is synchronized on the Java Thread object. So there
853 // cannot be a race to start the thread and hence for the thread to exit while
854 // we are working on it. Non-Java threads that start Java threads either have
855 // to do so in a context in which races are impossible, or should do appropriate
856 // locking.
857
858 void os::start_thread(Thread* thread) {
859 // guard suspend/resume
860 MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag);
861 OSThread* osthread = thread->osthread();
862 osthread->set_state(RUNNABLE);
863 pd_start_thread(thread);
864 }
865
866 void os::abort(bool dump_core) {
867 abort(dump_core && CreateCoredumpOnCrash, NULL, NULL);
868 }
869
870 //---------------------------------------------------------------------------
871 // Helper functions for fatal error handler
872
873 void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) {
874 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking");
875
876 int cols = 0;
877 int cols_per_line = 0;
878 switch (unitsize) {
879 case 1: cols_per_line = 16; break;
880 case 2: cols_per_line = 8; break;
881 case 4: cols_per_line = 4; break;
882 case 8: cols_per_line = 2; break;
883 default: return;
884 }
885
886 address p = start;
887 st->print(PTR_FORMAT ": ", p2i(start));
888 while (p < end) {
889 switch (unitsize) {
890 case 1: st->print("%02x", *(u1*)p); break;
891 case 2: st->print("%04x", *(u2*)p); break;
892 case 4: st->print("%08x", *(u4*)p); break;
893 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break;
894 }
895 p += unitsize;
896 cols++;
897 if (cols >= cols_per_line && p < end) {
898 cols = 0;
899 st->cr();
900 st->print(PTR_FORMAT ": ", p2i(p));
901 } else {
902 st->print(" ");
903 }
904 }
905 st->cr();
906 }
907
908 void os::print_environment_variables(outputStream* st, const char** env_list) {
909 if (env_list) {
910 st->print_cr("Environment Variables:");
911
912 for (int i = 0; env_list[i] != NULL; i++) {
913 char *envvar = ::getenv(env_list[i]);
914 if (envvar != NULL) {
915 st->print("%s", env_list[i]);
916 st->print("=");
917 st->print_cr("%s", envvar);
918 }
919 }
920 }
921 }
922
923 void os::print_cpu_info(outputStream* st, char* buf, size_t buflen) {
924 // cpu
925 st->print("CPU:");
926 st->print("total %d", os::processor_count());
927 // It's not safe to query number of active processors after crash
928 // st->print("(active %d)", os::active_processor_count()); but we can
929 // print the initial number of active processors.
930 // We access the raw value here because the assert in the accessor will
931 // fail if the crash occurs before initialization of this value.
932 st->print(" (initial active %d)", _initial_active_processor_count);
933 st->print(" %s", VM_Version::features_string());
934 st->cr();
935 pd_print_cpu_info(st, buf, buflen);
936 }
937
938 // Print a one line string summarizing the cpu, number of cores, memory, and operating system version
939 void os::print_summary_info(outputStream* st, char* buf, size_t buflen) {
940 st->print("Host: ");
941 #ifndef PRODUCT
942 if (get_host_name(buf, buflen)) {
943 st->print("%s, ", buf);
944 }
945 #endif // PRODUCT
946 get_summary_cpu_info(buf, buflen);
947 st->print("%s, ", buf);
948 size_t mem = physical_memory()/G;
949 if (mem == 0) { // for low memory systems
950 mem = physical_memory()/M;
951 st->print("%d cores, " SIZE_FORMAT "M, ", processor_count(), mem);
952 } else {
953 st->print("%d cores, " SIZE_FORMAT "G, ", processor_count(), mem);
954 }
955 get_summary_os_info(buf, buflen);
956 st->print_raw(buf);
957 st->cr();
958 }
959
960 void os::print_date_and_time(outputStream *st, char* buf, size_t buflen) {
961 const int secs_per_day = 86400;
962 const int secs_per_hour = 3600;
963 const int secs_per_min = 60;
964
965 time_t tloc;
966 (void)time(&tloc);
967 char* timestring = ctime(&tloc); // ctime adds newline.
968 // edit out the newline
969 char* nl = strchr(timestring, '\n');
970 if (nl != NULL) {
971 *nl = '\0';
972 }
973
974 struct tm tz;
975 if (localtime_pd(&tloc, &tz) != NULL) {
976 ::strftime(buf, buflen, "%Z", &tz);
977 st->print("Time: %s %s", timestring, buf);
978 } else {
979 st->print("Time: %s", timestring);
980 }
981
982 double t = os::elapsedTime();
983 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in
984 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int
985 // before printf. We lost some precision, but who cares?
986 int eltime = (int)t; // elapsed time in seconds
987
988 // print elapsed time in a human-readable format:
989 int eldays = eltime / secs_per_day;
990 int day_secs = eldays * secs_per_day;
991 int elhours = (eltime - day_secs) / secs_per_hour;
992 int hour_secs = elhours * secs_per_hour;
993 int elmins = (eltime - day_secs - hour_secs) / secs_per_min;
994 int minute_secs = elmins * secs_per_min;
995 int elsecs = (eltime - day_secs - hour_secs - minute_secs);
996 st->print_cr(" elapsed time: %d seconds (%dd %dh %dm %ds)", eltime, eldays, elhours, elmins, elsecs);
997 }
998
999
1000 // Check if pointer can be read from (4-byte read access).
1001 // Helps to prove validity of a not-NULL pointer.
1002 // Returns true in very early stages of VM life when stub is not yet generated.
1003 #define SAFEFETCH_DEFAULT true
1004 bool os::is_readable_pointer(const void* p) {
1005 if (!CanUseSafeFetch32()) {
1006 return SAFEFETCH_DEFAULT;
1007 }
1008 int* const aligned = (int*) align_down((intptr_t)p, 4);
1009 int cafebabe = 0xcafebabe; // tester value 1
1010 int deadbeef = 0xdeadbeef; // tester value 2
1011 return (SafeFetch32(aligned, cafebabe) != cafebabe) || (SafeFetch32(aligned, deadbeef) != deadbeef);
1012 }
1013
1014
1015 // moved from debug.cpp (used to be find()) but still called from there
1016 // The verbose parameter is only set by the debug code in one case
1017 void os::print_location(outputStream* st, intptr_t x, bool verbose) {
1018 address addr = (address)x;
1019 // Handle NULL first, so later checks don't need to protect against it.
1020 if (addr == NULL) {
1021 st->print_cr("0x0 is NULL");
1022 return;
1023 }
1024
1025 // Check if addr points into a code blob.
1026 CodeBlob* b = CodeCache::find_blob_unsafe(addr);
1027 if (b != NULL) {
1028 vmErrorHelper::dump_code_blob(addr, b, st, verbose);
1029 return;
1030 }
1031
1032 // Check if addr points into Java heap.
1033 if (Universe::heap()->is_in(addr)) {
1034 oop o = vmErrorHelper::oop_or_null(addr);
1035 if (o != NULL) {
1036 if ((HeapWord*)o == (HeapWord*)addr) {
1037 st->print(INTPTR_FORMAT " is an oop: ", p2i(addr));
1038 } else {
1039 st->print(INTPTR_FORMAT " is pointing into object: " , p2i(addr));
1040 }
1041 o->print_on(st);
1042 return;
1043 }
1044 } else if (Universe::heap()->is_in_reserved(addr)) {
1045 st->print_cr(INTPTR_FORMAT " is an unallocated location in the heap", p2i(addr));
1046 return;
1047 }
1048
1049 // Compressed oop needs to be decoded first.
1050 #ifdef _LP64
1051 if (UseCompressedOops && ((uintptr_t)addr &~ (uintptr_t)max_juint) == 0) {
1052 narrowOop narrow_oop = (narrowOop)(uintptr_t)addr;
1053 oop o = vmErrorHelper::decode_oop_raw(narrow_oop);
1054
1055 if (vmErrorHelper::is_valid_oop(o)) {
1056 st->print(UINT32_FORMAT " is a compressed pointer to object: ", narrow_oop);
1057 o->print_on(st);
1058 return;
1059 }
1060 }
1061 #endif
1062
1063 bool accessible = is_readable_pointer(addr);
1064
1065 // Check if addr is a JNI handle.
1066 if (align_down((intptr_t)addr, sizeof(intptr_t)) != 0 && accessible) {
1067 if (JNIHandles::is_global_handle((jobject) addr)) {
1068 st->print_cr(INTPTR_FORMAT " is a global jni handle", p2i(addr));
1069 return;
1070 }
1071 if (JNIHandles::is_weak_global_handle((jobject) addr)) {
1072 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", p2i(addr));
1073 return;
1074 }
1075 #ifndef PRODUCT
1076 // we don't keep the block list in product mode
1077 if (JNIHandles::is_local_handle((jobject) addr)) {
1078 st->print_cr(INTPTR_FORMAT " is a local jni handle", p2i(addr));
1079 return;
1080 }
1081 #endif
1082 }
1083
1084 // Check if addr belongs to a Java thread.
1085 for (JavaThreadIteratorWithHandle jtiwh; JavaThread *thread = jtiwh.next(); ) {
1086 // Check for privilege stack
1087 if (thread->privileged_stack_top() != NULL &&
1088 thread->privileged_stack_top()->contains(addr)) {
1089 st->print_cr(INTPTR_FORMAT " is pointing into the privilege stack "
1090 "for thread: " INTPTR_FORMAT, p2i(addr), p2i(thread));
1091 if (verbose) thread->print_on(st);
1092 return;
1093 }
1094 // If the addr is a java thread print information about that.
1095 if (addr == (address)thread) {
1096 if (verbose) {
1097 thread->print_on(st);
1098 } else {
1099 st->print_cr(INTPTR_FORMAT " is a thread", p2i(addr));
1100 }
1101 return;
1102 }
1103 // If the addr is in the stack region for this thread then report that
1104 // and print thread info
1105 if (thread->on_local_stack(addr)) {
1106 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: "
1107 INTPTR_FORMAT, p2i(addr), p2i(thread));
1108 if (verbose) thread->print_on(st);
1109 return;
1110 }
1111 }
1112
1113 // Check if in metaspace and print types that have vptrs (only method now)
1114 if (Metaspace::contains(addr)) {
1115 if (Method::has_method_vptr((const void*)addr)) {
1116 ((Method*)addr)->print_value_on(st);
1117 st->cr();
1118 } else {
1119 // Use addr->print() from the debugger instead (not here)
1120 st->print_cr(INTPTR_FORMAT " is pointing into metadata", p2i(addr));
1121 }
1122 return;
1123 }
1124
1125 // Compressed klass needs to be decoded first.
1126 #ifdef _LP64
1127 if (UseCompressedClassPointers && ((uintptr_t)addr &~ (uintptr_t)max_juint) == 0) {
1128 narrowKlass narrow_klass = (narrowKlass)(uintptr_t)addr;
1129 Klass* k = vmErrorHelper::decode_klass_raw(narrow_klass);
1130
1131 if (vmErrorHelper::is_valid_klass(k)) {
1132 st->print_cr(UINT32_FORMAT " is a compressed pointer to class: " INTPTR_FORMAT, narrow_klass, p2i((HeapWord*)k));
1133 k->print_on(st);
1134 return;
1135 }
1136 }
1137 #endif
1138
1139 // Try an OS specific find
1140 if (os::find(addr, st)) {
1141 return;
1142 }
1143
1144 if (accessible) {
1145 st->print_cr(INTPTR_FORMAT " points into unknown readable memory", p2i(addr));
1146 return;
1147 }
1148
1149 st->print_cr(INTPTR_FORMAT " is an unknown value", p2i(addr));
1150 }
1151
1152 // Looks like all platforms can use the same function to check if C
1153 // stack is walkable beyond current frame. The check for fp() is not
1154 // necessary on Sparc, but it's harmless.
1155 bool os::is_first_C_frame(frame* fr) {
1156 // Load up sp, fp, sender sp and sender fp, check for reasonable values.
1157 // Check usp first, because if that's bad the other accessors may fault
1158 // on some architectures. Ditto ufp second, etc.
1159 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1);
1160 // sp on amd can be 32 bit aligned.
1161 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1);
1162
1163 uintptr_t usp = (uintptr_t)fr->sp();
1164 if ((usp & sp_align_mask) != 0) return true;
1165
1166 uintptr_t ufp = (uintptr_t)fr->fp();
1167 if ((ufp & fp_align_mask) != 0) return true;
1168
1169 uintptr_t old_sp = (uintptr_t)fr->sender_sp();
1170 if ((old_sp & sp_align_mask) != 0) return true;
1171 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true;
1172
1173 uintptr_t old_fp = (uintptr_t)fr->link();
1174 if ((old_fp & fp_align_mask) != 0) return true;
1175 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true;
1176
1177 // stack grows downwards; if old_fp is below current fp or if the stack
1178 // frame is too large, either the stack is corrupted or fp is not saved
1179 // on stack (i.e. on x86, ebp may be used as general register). The stack
1180 // is not walkable beyond current frame.
1181 if (old_fp < ufp) return true;
1182 if (old_fp - ufp > 64 * K) return true;
1183
1184 return false;
1185 }
1186
1187
1188 // Set up the boot classpath.
1189
1190 char* os::format_boot_path(const char* format_string,
1191 const char* home,
1192 int home_len,
1193 char fileSep,
1194 char pathSep) {
1195 assert((fileSep == '/' && pathSep == ':') ||
1196 (fileSep == '\\' && pathSep == ';'), "unexpected separator chars");
1197
1198 // Scan the format string to determine the length of the actual
1199 // boot classpath, and handle platform dependencies as well.
1200 int formatted_path_len = 0;
1201 const char* p;
1202 for (p = format_string; *p != 0; ++p) {
1203 if (*p == '%') formatted_path_len += home_len - 1;
1204 ++formatted_path_len;
1205 }
1206
1207 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal);
1208 if (formatted_path == NULL) {
1209 return NULL;
1210 }
1211
1212 // Create boot classpath from format, substituting separator chars and
1213 // java home directory.
1214 char* q = formatted_path;
1215 for (p = format_string; *p != 0; ++p) {
1216 switch (*p) {
1217 case '%':
1218 strcpy(q, home);
1219 q += home_len;
1220 break;
1221 case '/':
1222 *q++ = fileSep;
1223 break;
1224 case ':':
1225 *q++ = pathSep;
1226 break;
1227 default:
1228 *q++ = *p;
1229 }
1230 }
1231 *q = '\0';
1232
1233 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched");
1234 return formatted_path;
1235 }
1236
1237 // This function is a proxy to fopen, it tries to add a non standard flag ('e' or 'N')
1238 // that ensures automatic closing of the file on exec. If it can not find support in
1239 // the underlying c library, it will make an extra system call (fcntl) to ensure automatic
1240 // closing of the file on exec.
1241 FILE* os::fopen(const char* path, const char* mode) {
1242 char modified_mode[20];
1243 assert(strlen(mode) + 1 < sizeof(modified_mode), "mode chars plus one extra must fit in buffer");
1244 sprintf(modified_mode, "%s" LINUX_ONLY("e") BSD_ONLY("e") WINDOWS_ONLY("N"), mode);
1245 FILE* file = ::fopen(path, modified_mode);
1246
1247 #if !(defined LINUX || defined BSD || defined _WINDOWS)
1248 // assume fcntl FD_CLOEXEC support as a backup solution when 'e' or 'N'
1249 // is not supported as mode in fopen
1250 if (file != NULL) {
1251 int fd = fileno(file);
1252 if (fd != -1) {
1253 int fd_flags = fcntl(fd, F_GETFD);
1254 if (fd_flags != -1) {
1255 fcntl(fd, F_SETFD, fd_flags | FD_CLOEXEC);
1256 }
1257 }
1258 }
1259 #endif
1260
1261 return file;
1262 }
1263
1264 bool os::set_boot_path(char fileSep, char pathSep) {
1265 const char* home = Arguments::get_java_home();
1266 int home_len = (int)strlen(home);
1267
1268 struct stat st;
1269
1270 // modular image if "modules" jimage exists
1271 char* jimage = format_boot_path("%/lib/" MODULES_IMAGE_NAME, home, home_len, fileSep, pathSep);
1272 if (jimage == NULL) return false;
1273 bool has_jimage = (os::stat(jimage, &st) == 0);
1274 if (has_jimage) {
1275 Arguments::set_sysclasspath(jimage, true);
1276 FREE_C_HEAP_ARRAY(char, jimage);
1277 return true;
1278 }
1279 FREE_C_HEAP_ARRAY(char, jimage);
1280
1281 // check if developer build with exploded modules
1282 char* base_classes = format_boot_path("%/modules/" JAVA_BASE_NAME, home, home_len, fileSep, pathSep);
1283 if (base_classes == NULL) return false;
1284 if (os::stat(base_classes, &st) == 0) {
1285 Arguments::set_sysclasspath(base_classes, false);
1286 FREE_C_HEAP_ARRAY(char, base_classes);
1287 return true;
1288 }
1289 FREE_C_HEAP_ARRAY(char, base_classes);
1290
1291 return false;
1292 }
1293
1294 /*
1295 * Splits a path, based on its separator, the number of
1296 * elements is returned back in n.
1297 * It is the callers responsibility to:
1298 * a> check the value of n, and n may be 0.
1299 * b> ignore any empty path elements
1300 * c> free up the data.
1301 */
1302 char** os::split_path(const char* path, int* n) {
1303 *n = 0;
1304 if (path == NULL || strlen(path) == 0) {
1305 return NULL;
1306 }
1307 const char psepchar = *os::path_separator();
1308 char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal);
1309 if (inpath == NULL) {
1310 return NULL;
1311 }
1312 strcpy(inpath, path);
1313 int count = 1;
1314 char* p = strchr(inpath, psepchar);
1315 // Get a count of elements to allocate memory
1316 while (p != NULL) {
1317 count++;
1318 p++;
1319 p = strchr(p, psepchar);
1320 }
1321 char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count, mtInternal);
1322 if (opath == NULL) {
1323 return NULL;
1324 }
1325
1326 // do the actual splitting
1327 p = inpath;
1328 for (int i = 0 ; i < count ; i++) {
1329 size_t len = strcspn(p, os::path_separator());
1330 if (len > JVM_MAXPATHLEN) {
1331 return NULL;
1332 }
1333 // allocate the string and add terminator storage
1334 char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
1335 if (s == NULL) {
1336 return NULL;
1337 }
1338 strncpy(s, p, len);
1339 s[len] = '\0';
1340 opath[i] = s;
1341 p += len + 1;
1342 }
1343 FREE_C_HEAP_ARRAY(char, inpath);
1344 *n = count;
1345 return opath;
1346 }
1347
1348 void os::set_memory_serialize_page(address page) {
1349 int count = log2_intptr(sizeof(class JavaThread)) - log2_intptr(64);
1350 _mem_serialize_page = (volatile int32_t *)page;
1351 // We initialize the serialization page shift count here
1352 // We assume a cache line size of 64 bytes
1353 assert(SerializePageShiftCount == count, "JavaThread size changed; "
1354 "SerializePageShiftCount constant should be %d", count);
1355 set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t)));
1356 }
1357
1358 static volatile intptr_t SerializePageLock = 0;
1359
1360 // This method is called from signal handler when SIGSEGV occurs while the current
1361 // thread tries to store to the "read-only" memory serialize page during state
1362 // transition.
1363 void os::block_on_serialize_page_trap() {
1364 log_debug(safepoint)("Block until the serialize page permission restored");
1365
1366 // When VMThread is holding the SerializePageLock during modifying the
1367 // access permission of the memory serialize page, the following call
1368 // will block until the permission of that page is restored to rw.
1369 // Generally, it is unsafe to manipulate locks in signal handlers, but in
1370 // this case, it's OK as the signal is synchronous and we know precisely when
1371 // it can occur.
1372 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page");
1373 Thread::muxRelease(&SerializePageLock);
1374 }
1375
1376 // Serialize all thread state variables
1377 void os::serialize_thread_states() {
1378 // On some platforms such as Solaris & Linux, the time duration of the page
1379 // permission restoration is observed to be much longer than expected due to
1380 // scheduler starvation problem etc. To avoid the long synchronization
1381 // time and expensive page trap spinning, 'SerializePageLock' is used to block
1382 // the mutator thread if such case is encountered. See bug 6546278 for details.
1383 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states");
1384 os::protect_memory((char *)os::get_memory_serialize_page(),
1385 os::vm_page_size(), MEM_PROT_READ);
1386 os::protect_memory((char *)os::get_memory_serialize_page(),
1387 os::vm_page_size(), MEM_PROT_RW);
1388 Thread::muxRelease(&SerializePageLock);
1389 }
1390
1391 // Returns true if the current stack pointer is above the stack shadow
1392 // pages, false otherwise.
1393 bool os::stack_shadow_pages_available(Thread *thread, const methodHandle& method, address sp) {
1394 if (!thread->is_Java_thread()) return false;
1395 // Check if we have StackShadowPages above the yellow zone. This parameter
1396 // is dependent on the depth of the maximum VM call stack possible from
1397 // the handler for stack overflow. 'instanceof' in the stack overflow
1398 // handler or a println uses at least 8k stack of VM and native code
1399 // respectively.
1400 const int framesize_in_bytes =
1401 Interpreter::size_top_interpreter_activation(method()) * wordSize;
1402
1403 address limit = ((JavaThread*)thread)->stack_end() +
1404 (JavaThread::stack_guard_zone_size() + JavaThread::stack_shadow_zone_size());
1405
1406 return sp > (limit + framesize_in_bytes);
1407 }
1408
1409 size_t os::page_size_for_region(size_t region_size, size_t min_pages, bool must_be_aligned) {
1410 assert(min_pages > 0, "sanity");
1411 if (UseLargePages) {
1412 const size_t max_page_size = region_size / min_pages;
1413
1414 for (size_t i = 0; _page_sizes[i] != 0; ++i) {
1415 const size_t page_size = _page_sizes[i];
1416 if (page_size <= max_page_size) {
1417 if (!must_be_aligned || is_aligned(region_size, page_size)) {
1418 return page_size;
1419 }
1420 }
1421 }
1422 }
1423
1424 return vm_page_size();
1425 }
1426
1427 size_t os::page_size_for_region_aligned(size_t region_size, size_t min_pages) {
1428 return page_size_for_region(region_size, min_pages, true);
1429 }
1430
1431 size_t os::page_size_for_region_unaligned(size_t region_size, size_t min_pages) {
1432 return page_size_for_region(region_size, min_pages, false);
1433 }
1434
1435 static const char* errno_to_string (int e, bool short_text) {
1436 #define ALL_SHARED_ENUMS(X) \
1437 X(E2BIG, "Argument list too long") \
1438 X(EACCES, "Permission denied") \
1439 X(EADDRINUSE, "Address in use") \
1440 X(EADDRNOTAVAIL, "Address not available") \
1441 X(EAFNOSUPPORT, "Address family not supported") \
1442 X(EAGAIN, "Resource unavailable, try again") \
1443 X(EALREADY, "Connection already in progress") \
1444 X(EBADF, "Bad file descriptor") \
1445 X(EBADMSG, "Bad message") \
1446 X(EBUSY, "Device or resource busy") \
1447 X(ECANCELED, "Operation canceled") \
1448 X(ECHILD, "No child processes") \
1449 X(ECONNABORTED, "Connection aborted") \
1450 X(ECONNREFUSED, "Connection refused") \
1451 X(ECONNRESET, "Connection reset") \
1452 X(EDEADLK, "Resource deadlock would occur") \
1453 X(EDESTADDRREQ, "Destination address required") \
1454 X(EDOM, "Mathematics argument out of domain of function") \
1455 X(EEXIST, "File exists") \
1456 X(EFAULT, "Bad address") \
1457 X(EFBIG, "File too large") \
1458 X(EHOSTUNREACH, "Host is unreachable") \
1459 X(EIDRM, "Identifier removed") \
1460 X(EILSEQ, "Illegal byte sequence") \
1461 X(EINPROGRESS, "Operation in progress") \
1462 X(EINTR, "Interrupted function") \
1463 X(EINVAL, "Invalid argument") \
1464 X(EIO, "I/O error") \
1465 X(EISCONN, "Socket is connected") \
1466 X(EISDIR, "Is a directory") \
1467 X(ELOOP, "Too many levels of symbolic links") \
1468 X(EMFILE, "Too many open files") \
1469 X(EMLINK, "Too many links") \
1470 X(EMSGSIZE, "Message too large") \
1471 X(ENAMETOOLONG, "Filename too long") \
1472 X(ENETDOWN, "Network is down") \
1473 X(ENETRESET, "Connection aborted by network") \
1474 X(ENETUNREACH, "Network unreachable") \
1475 X(ENFILE, "Too many files open in system") \
1476 X(ENOBUFS, "No buffer space available") \
1477 X(ENODATA, "No message is available on the STREAM head read queue") \
1478 X(ENODEV, "No such device") \
1479 X(ENOENT, "No such file or directory") \
1480 X(ENOEXEC, "Executable file format error") \
1481 X(ENOLCK, "No locks available") \
1482 X(ENOLINK, "Reserved") \
1483 X(ENOMEM, "Not enough space") \
1484 X(ENOMSG, "No message of the desired type") \
1485 X(ENOPROTOOPT, "Protocol not available") \
1486 X(ENOSPC, "No space left on device") \
1487 X(ENOSR, "No STREAM resources") \
1488 X(ENOSTR, "Not a STREAM") \
1489 X(ENOSYS, "Function not supported") \
1490 X(ENOTCONN, "The socket is not connected") \
1491 X(ENOTDIR, "Not a directory") \
1492 X(ENOTEMPTY, "Directory not empty") \
1493 X(ENOTSOCK, "Not a socket") \
1494 X(ENOTSUP, "Not supported") \
1495 X(ENOTTY, "Inappropriate I/O control operation") \
1496 X(ENXIO, "No such device or address") \
1497 X(EOPNOTSUPP, "Operation not supported on socket") \
1498 X(EOVERFLOW, "Value too large to be stored in data type") \
1499 X(EPERM, "Operation not permitted") \
1500 X(EPIPE, "Broken pipe") \
1501 X(EPROTO, "Protocol error") \
1502 X(EPROTONOSUPPORT, "Protocol not supported") \
1503 X(EPROTOTYPE, "Protocol wrong type for socket") \
1504 X(ERANGE, "Result too large") \
1505 X(EROFS, "Read-only file system") \
1506 X(ESPIPE, "Invalid seek") \
1507 X(ESRCH, "No such process") \
1508 X(ETIME, "Stream ioctl() timeout") \
1509 X(ETIMEDOUT, "Connection timed out") \
1510 X(ETXTBSY, "Text file busy") \
1511 X(EWOULDBLOCK, "Operation would block") \
1512 X(EXDEV, "Cross-device link")
1513
1514 #define DEFINE_ENTRY(e, text) { e, #e, text },
1515
1516 static const struct {
1517 int v;
1518 const char* short_text;
1519 const char* long_text;
1520 } table [] = {
1521
1522 ALL_SHARED_ENUMS(DEFINE_ENTRY)
1523
1524 // The following enums are not defined on all platforms.
1525 #ifdef ESTALE
1526 DEFINE_ENTRY(ESTALE, "Reserved")
1527 #endif
1528 #ifdef EDQUOT
1529 DEFINE_ENTRY(EDQUOT, "Reserved")
1530 #endif
1531 #ifdef EMULTIHOP
1532 DEFINE_ENTRY(EMULTIHOP, "Reserved")
1533 #endif
1534
1535 // End marker.
1536 { -1, "Unknown errno", "Unknown error" }
1537
1538 };
1539
1540 #undef DEFINE_ENTRY
1541 #undef ALL_FLAGS
1542
1543 int i = 0;
1544 while (table[i].v != -1 && table[i].v != e) {
1545 i ++;
1546 }
1547
1548 return short_text ? table[i].short_text : table[i].long_text;
1549
1550 }
1551
1552 const char* os::strerror(int e) {
1553 return errno_to_string(e, false);
1554 }
1555
1556 const char* os::errno_name(int e) {
1557 return errno_to_string(e, true);
1558 }
1559
1560 void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count) {
1561 LogTarget(Info, pagesize) log;
1562 if (log.is_enabled()) {
1563 LogStream out(log);
1564
1565 out.print("%s: ", str);
1566 for (int i = 0; i < count; ++i) {
1567 out.print(" " SIZE_FORMAT, page_sizes[i]);
1568 }
1569 out.cr();
1570 }
1571 }
1572
1573 #define trace_page_size_params(size) byte_size_in_exact_unit(size), exact_unit_for_byte_size(size)
1574
1575 void os::trace_page_sizes(const char* str,
1576 const size_t region_min_size,
1577 const size_t region_max_size,
1578 const size_t page_size,
1579 const char* base,
1580 const size_t size) {
1581
1582 log_info(pagesize)("%s: "
1583 " min=" SIZE_FORMAT "%s"
1584 " max=" SIZE_FORMAT "%s"
1585 " base=" PTR_FORMAT
1586 " page_size=" SIZE_FORMAT "%s"
1587 " size=" SIZE_FORMAT "%s",
1588 str,
1589 trace_page_size_params(region_min_size),
1590 trace_page_size_params(region_max_size),
1591 p2i(base),
1592 trace_page_size_params(page_size),
1593 trace_page_size_params(size));
1594 }
1595
1596 void os::trace_page_sizes_for_requested_size(const char* str,
1597 const size_t requested_size,
1598 const size_t page_size,
1599 const size_t alignment,
1600 const char* base,
1601 const size_t size) {
1602
1603 log_info(pagesize)("%s:"
1604 " req_size=" SIZE_FORMAT "%s"
1605 " base=" PTR_FORMAT
1606 " page_size=" SIZE_FORMAT "%s"
1607 " alignment=" SIZE_FORMAT "%s"
1608 " size=" SIZE_FORMAT "%s",
1609 str,
1610 trace_page_size_params(requested_size),
1611 p2i(base),
1612 trace_page_size_params(page_size),
1613 trace_page_size_params(alignment),
1614 trace_page_size_params(size));
1615 }
1616
1617
1618 // This is the working definition of a server class machine:
1619 // >= 2 physical CPU's and >=2GB of memory, with some fuzz
1620 // because the graphics memory (?) sometimes masks physical memory.
1621 // If you want to change the definition of a server class machine
1622 // on some OS or platform, e.g., >=4GB on Windows platforms,
1623 // then you'll have to parameterize this method based on that state,
1624 // as was done for logical processors here, or replicate and
1625 // specialize this method for each platform. (Or fix os to have
1626 // some inheritance structure and use subclassing. Sigh.)
1627 // If you want some platform to always or never behave as a server
1628 // class machine, change the setting of AlwaysActAsServerClassMachine
1629 // and NeverActAsServerClassMachine in globals*.hpp.
1630 bool os::is_server_class_machine() {
1631 // First check for the early returns
1632 if (NeverActAsServerClassMachine) {
1633 return false;
1634 }
1635 if (AlwaysActAsServerClassMachine) {
1636 return true;
1637 }
1638 // Then actually look at the machine
1639 bool result = false;
1640 const unsigned int server_processors = 2;
1641 const julong server_memory = 2UL * G;
1642 // We seem not to get our full complement of memory.
1643 // We allow some part (1/8?) of the memory to be "missing",
1644 // based on the sizes of DIMMs, and maybe graphics cards.
1645 const julong missing_memory = 256UL * M;
1646
1647 /* Is this a server class machine? */
1648 if ((os::active_processor_count() >= (int)server_processors) &&
1649 (os::physical_memory() >= (server_memory - missing_memory))) {
1650 const unsigned int logical_processors =
1651 VM_Version::logical_processors_per_package();
1652 if (logical_processors > 1) {
1653 const unsigned int physical_packages =
1654 os::active_processor_count() / logical_processors;
1655 if (physical_packages >= server_processors) {
1656 result = true;
1657 }
1658 } else {
1659 result = true;
1660 }
1661 }
1662 return result;
1663 }
1664
1665 void os::initialize_initial_active_processor_count() {
1666 assert(_initial_active_processor_count == 0, "Initial active processor count already set.");
1667 _initial_active_processor_count = active_processor_count();
1668 log_debug(os)("Initial active processor count set to %d" , _initial_active_processor_count);
1669 }
1670
1671 void os::SuspendedThreadTask::run() {
1672 internal_do_task();
1673 _done = true;
1674 }
1675
1676 bool os::create_stack_guard_pages(char* addr, size_t bytes) {
1677 return os::pd_create_stack_guard_pages(addr, bytes);
1678 }
1679
1680 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint, int file_desc) {
1681 char* result = NULL;
1682
1683 if (file_desc != -1) {
1684 // Could have called pd_reserve_memory() followed by replace_existing_mapping_with_file_mapping(),
1685 // but AIX may use SHM in which case its more trouble to detach the segment and remap memory to the file.
1686 result = os::map_memory_to_file(addr, bytes, file_desc);
1687 if (result != NULL) {
1688 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC);
1689 }
1690 } else {
1691 result = pd_reserve_memory(bytes, addr, alignment_hint);
1692 if (result != NULL) {
1693 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1694 }
1695 }
1696
1697 return result;
1698 }
1699
1700 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint,
1701 MEMFLAGS flags) {
1702 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1703 if (result != NULL) {
1704 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1705 MemTracker::record_virtual_memory_type((address)result, flags);
1706 }
1707
1708 return result;
1709 }
1710
1711 char* os::attempt_reserve_memory_at(size_t bytes, char* addr, int file_desc) {
1712 char* result = NULL;
1713 if (file_desc != -1) {
1714 result = pd_attempt_reserve_memory_at(bytes, addr, file_desc);
1715 if (result != NULL) {
1716 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC);
1717 }
1718 } else {
1719 result = pd_attempt_reserve_memory_at(bytes, addr);
1720 if (result != NULL) {
1721 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1722 }
1723 }
1724 return result;
1725 }
1726
1727 void os::split_reserved_memory(char *base, size_t size,
1728 size_t split, bool realloc) {
1729 pd_split_reserved_memory(base, size, split, realloc);
1730 }
1731
1732 bool os::commit_memory(char* addr, size_t bytes, bool executable) {
1733 bool res = pd_commit_memory(addr, bytes, executable);
1734 if (res) {
1735 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1736 }
1737 return res;
1738 }
1739
1740 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint,
1741 bool executable) {
1742 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable);
1743 if (res) {
1744 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1745 }
1746 return res;
1747 }
1748
1749 void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable,
1750 const char* mesg) {
1751 pd_commit_memory_or_exit(addr, bytes, executable, mesg);
1752 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1753 }
1754
1755 void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint,
1756 bool executable, const char* mesg) {
1757 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg);
1758 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1759 }
1760
1761 bool os::uncommit_memory(char* addr, size_t bytes) {
1762 bool res;
1763 if (MemTracker::tracking_level() > NMT_minimal) {
1764 Tracker tkr(Tracker::uncommit);
1765 res = pd_uncommit_memory(addr, bytes);
1766 if (res) {
1767 tkr.record((address)addr, bytes);
1768 }
1769 } else {
1770 res = pd_uncommit_memory(addr, bytes);
1771 }
1772 return res;
1773 }
1774
1775 bool os::release_memory(char* addr, size_t bytes) {
1776 bool res;
1777 if (MemTracker::tracking_level() > NMT_minimal) {
1778 Tracker tkr(Tracker::release);
1779 res = pd_release_memory(addr, bytes);
1780 if (res) {
1781 tkr.record((address)addr, bytes);
1782 }
1783 } else {
1784 res = pd_release_memory(addr, bytes);
1785 }
1786 return res;
1787 }
1788
1789 void os::pretouch_memory(void* start, void* end, size_t page_size) {
1790 for (volatile char *p = (char*)start; p < (char*)end; p += page_size) {
1791 *p = 0;
1792 }
1793 }
1794
1795 char* os::map_memory(int fd, const char* file_name, size_t file_offset,
1796 char *addr, size_t bytes, bool read_only,
1797 bool allow_exec) {
1798 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec);
1799 if (result != NULL) {
1800 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC);
1801 }
1802 return result;
1803 }
1804
1805 char* os::remap_memory(int fd, const char* file_name, size_t file_offset,
1806 char *addr, size_t bytes, bool read_only,
1807 bool allow_exec) {
1808 return pd_remap_memory(fd, file_name, file_offset, addr, bytes,
1809 read_only, allow_exec);
1810 }
1811
1812 bool os::unmap_memory(char *addr, size_t bytes) {
1813 bool result;
1814 if (MemTracker::tracking_level() > NMT_minimal) {
1815 Tracker tkr(Tracker::release);
1816 result = pd_unmap_memory(addr, bytes);
1817 if (result) {
1818 tkr.record((address)addr, bytes);
1819 }
1820 } else {
1821 result = pd_unmap_memory(addr, bytes);
1822 }
1823 return result;
1824 }
1825
1826 void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) {
1827 pd_free_memory(addr, bytes, alignment_hint);
1828 }
1829
1830 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
1831 pd_realign_memory(addr, bytes, alignment_hint);
1832 }
1833
1834 #ifndef _WINDOWS
1835 /* try to switch state from state "from" to state "to"
1836 * returns the state set after the method is complete
1837 */
1838 os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from,
1839 os::SuspendResume::State to)
1840 {
1841 os::SuspendResume::State result = Atomic::cmpxchg(to, &_state, from);
1842 if (result == from) {
1843 // success
1844 return to;
1845 }
1846 return result;
1847 }
1848 #endif