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 "runtime/arguments.hpp"
48 #include "runtime/atomic.hpp"
49 #include "runtime/frame.inline.hpp"
50 #include "runtime/interfaceSupport.inline.hpp"
51 #include "runtime/java.hpp"
52 #include "runtime/javaCalls.hpp"
53 #include "runtime/mutexLocker.hpp"
54 #include "runtime/os.inline.hpp"
55 #include "runtime/sharedRuntime.hpp"
56 #include "runtime/stubRoutines.hpp"
57 #include "runtime/thread.inline.hpp"
58 #include "runtime/threadSMR.hpp"
59 #include "runtime/vm_version.hpp"
60 #include "services/attachListener.hpp"
61 #include "services/mallocTracker.hpp"
62 #include "services/memTracker.hpp"
63 #include "services/nmtCommon.hpp"
64 #include "services/threadService.hpp"
65 #include "utilities/align.hpp"
66 #include "utilities/defaultStream.hpp"
67 #include "utilities/events.hpp"
68
69 # include <signal.h>
70 # include <errno.h>
71
72 OSThread* os::_starting_thread = NULL;
73 address os::_polling_page = NULL;
74 volatile int32_t* os::_mem_serialize_page = NULL;
75 uintptr_t os::_serialize_page_mask = 0;
76 volatile unsigned int os::_rand_seed = 1;
77 int os::_processor_count = 0;
78 int os::_initial_active_processor_count = 0;
79 size_t os::_page_sizes[os::page_sizes_max];
80
81 #ifndef PRODUCT
82 julong os::num_mallocs = 0; // # of calls to malloc/realloc
83 julong os::alloc_bytes = 0; // # of bytes allocated
84 julong os::num_frees = 0; // # of calls to free
85 julong os::free_bytes = 0; // # of bytes freed
86 #endif
87
88 static size_t cur_malloc_words = 0; // current size for MallocMaxTestWords
89
90 void os_init_globals() {
91 // Called from init_globals().
92 // See Threads::create_vm() in thread.cpp, and init.cpp.
93 os::init_globals();
94 }
95
96 static time_t get_timezone(const struct tm* time_struct) {
97 #if defined(_ALLBSD_SOURCE)
98 return time_struct->tm_gmtoff;
99 #elif defined(_WINDOWS)
100 long zone;
101 _get_timezone(&zone);
102 return static_cast<time_t>(zone);
103 #else
104 return timezone;
105 #endif
106 }
107
108 int os::snprintf(char* buf, size_t len, const char* fmt, ...) {
109 va_list args;
110 va_start(args, fmt);
111 int result = os::vsnprintf(buf, len, fmt, args);
112 va_end(args);
113 return result;
114 }
115
116 // Fill in buffer with current local time as an ISO-8601 string.
117 // E.g., yyyy-mm-ddThh:mm:ss-zzzz.
118 // Returns buffer, or NULL if it failed.
119 // This would mostly be a call to
120 // strftime(...., "%Y-%m-%d" "T" "%H:%M:%S" "%z", ....)
121 // except that on Windows the %z behaves badly, so we do it ourselves.
122 // Also, people wanted milliseconds on there,
123 // and strftime doesn't do milliseconds.
124 char* os::iso8601_time(char* buffer, size_t buffer_length, bool utc) {
125 // Output will be of the form "YYYY-MM-DDThh:mm:ss.mmm+zzzz\0"
126 // 1 2
127 // 12345678901234567890123456789
128 // format string: "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d"
129 static const size_t needed_buffer = 29;
130
131 // Sanity check the arguments
132 if (buffer == NULL) {
133 assert(false, "NULL buffer");
134 return NULL;
135 }
136 if (buffer_length < needed_buffer) {
137 assert(false, "buffer_length too small");
138 return NULL;
139 }
140 // Get the current time
141 jlong milliseconds_since_19700101 = javaTimeMillis();
142 const int milliseconds_per_microsecond = 1000;
143 const time_t seconds_since_19700101 =
144 milliseconds_since_19700101 / milliseconds_per_microsecond;
145 const int milliseconds_after_second =
146 milliseconds_since_19700101 % milliseconds_per_microsecond;
147 // Convert the time value to a tm and timezone variable
148 struct tm time_struct;
149 if (utc) {
150 if (gmtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
151 assert(false, "Failed gmtime_pd");
152 return NULL;
153 }
154 } else {
155 if (localtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
156 assert(false, "Failed localtime_pd");
157 return NULL;
158 }
159 }
160 const time_t zone = get_timezone(&time_struct);
161
162 // If daylight savings time is in effect,
163 // we are 1 hour East of our time zone
164 const time_t seconds_per_minute = 60;
165 const time_t minutes_per_hour = 60;
166 const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour;
167 time_t UTC_to_local = zone;
168 if (time_struct.tm_isdst > 0) {
169 UTC_to_local = UTC_to_local - seconds_per_hour;
170 }
171
172 // No offset when dealing with UTC
173 if (utc) {
174 UTC_to_local = 0;
175 }
176
177 // Compute the time zone offset.
178 // localtime_pd() sets timezone to the difference (in seconds)
179 // between UTC and and local time.
180 // ISO 8601 says we need the difference between local time and UTC,
181 // we change the sign of the localtime_pd() result.
182 const time_t local_to_UTC = -(UTC_to_local);
183 // Then we have to figure out if if we are ahead (+) or behind (-) UTC.
184 char sign_local_to_UTC = '+';
185 time_t abs_local_to_UTC = local_to_UTC;
186 if (local_to_UTC < 0) {
187 sign_local_to_UTC = '-';
188 abs_local_to_UTC = -(abs_local_to_UTC);
189 }
190 // Convert time zone offset seconds to hours and minutes.
191 const time_t zone_hours = (abs_local_to_UTC / seconds_per_hour);
192 const time_t zone_min =
193 ((abs_local_to_UTC % seconds_per_hour) / seconds_per_minute);
194
195 // Print an ISO 8601 date and time stamp into the buffer
196 const int year = 1900 + time_struct.tm_year;
197 const int month = 1 + time_struct.tm_mon;
198 const int printed = jio_snprintf(buffer, buffer_length,
199 "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d",
200 year,
201 month,
202 time_struct.tm_mday,
203 time_struct.tm_hour,
204 time_struct.tm_min,
205 time_struct.tm_sec,
206 milliseconds_after_second,
207 sign_local_to_UTC,
208 zone_hours,
209 zone_min);
210 if (printed == 0) {
211 assert(false, "Failed jio_printf");
212 return NULL;
213 }
214 return buffer;
215 }
216
217 OSReturn os::set_priority(Thread* thread, ThreadPriority p) {
218 debug_only(Thread::check_for_dangling_thread_pointer(thread);)
219
220 if (p >= MinPriority && p <= MaxPriority) {
221 int priority = java_to_os_priority[p];
222 return set_native_priority(thread, priority);
223 } else {
224 assert(false, "Should not happen");
225 return OS_ERR;
226 }
227 }
228
229 // The mapping from OS priority back to Java priority may be inexact because
230 // Java priorities can map M:1 with native priorities. If you want the definite
231 // Java priority then use JavaThread::java_priority()
232 OSReturn os::get_priority(const Thread* const thread, ThreadPriority& priority) {
233 int p;
234 int os_prio;
235 OSReturn ret = get_native_priority(thread, &os_prio);
236 if (ret != OS_OK) return ret;
237
238 if (java_to_os_priority[MaxPriority] > java_to_os_priority[MinPriority]) {
239 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] > os_prio; p--) ;
240 } else {
241 // niceness values are in reverse order
242 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] < os_prio; p--) ;
243 }
244 priority = (ThreadPriority)p;
245 return OS_OK;
246 }
247
248 bool os::dll_build_name(char* buffer, size_t size, const char* fname) {
249 int n = jio_snprintf(buffer, size, "%s%s%s", JNI_LIB_PREFIX, fname, JNI_LIB_SUFFIX);
250 return (n != -1);
251 }
252
253 #if !defined(LINUX) && !defined(_WINDOWS)
254 bool os::committed_in_range(address start, size_t size, address& committed_start, size_t& committed_size) {
255 committed_start = start;
256 committed_size = size;
257 return true;
258 }
259 #endif
260
261 // Helper for dll_locate_lib.
262 // Pass buffer and printbuffer as we already printed the path to buffer
263 // when we called get_current_directory. This way we avoid another buffer
264 // of size MAX_PATH.
265 static bool conc_path_file_and_check(char *buffer, char *printbuffer, size_t printbuflen,
266 const char* pname, char lastchar, const char* fname) {
267
268 // Concatenate path and file name, but don't print double path separators.
269 const char *filesep = (WINDOWS_ONLY(lastchar == ':' ||) lastchar == os::file_separator()[0]) ?
270 "" : os::file_separator();
271 int ret = jio_snprintf(printbuffer, printbuflen, "%s%s%s", pname, filesep, fname);
272 // Check whether file exists.
273 if (ret != -1) {
274 struct stat statbuf;
275 return os::stat(buffer, &statbuf) == 0;
276 }
277 return false;
278 }
279
280 bool os::dll_locate_lib(char *buffer, size_t buflen,
281 const char* pname, const char* fname) {
282 bool retval = false;
283
284 size_t fullfnamelen = strlen(JNI_LIB_PREFIX) + strlen(fname) + strlen(JNI_LIB_SUFFIX);
285 char* fullfname = (char*)NEW_C_HEAP_ARRAY(char, fullfnamelen + 1, mtInternal);
286 if (dll_build_name(fullfname, fullfnamelen + 1, fname)) {
287 const size_t pnamelen = pname ? strlen(pname) : 0;
288
289 if (pnamelen == 0) {
290 // If no path given, use current working directory.
291 const char* p = get_current_directory(buffer, buflen);
292 if (p != NULL) {
293 const size_t plen = strlen(buffer);
294 const char lastchar = buffer[plen - 1];
295 retval = conc_path_file_and_check(buffer, &buffer[plen], buflen - plen,
296 "", lastchar, fullfname);
297 }
298 } else if (strchr(pname, *os::path_separator()) != NULL) {
299 // A list of paths. Search for the path that contains the library.
300 int n;
301 char** pelements = split_path(pname, &n);
302 if (pelements != NULL) {
303 for (int i = 0; i < n; i++) {
304 char* path = pelements[i];
305 // Really shouldn't be NULL, but check can't hurt.
306 size_t plen = (path == NULL) ? 0 : strlen(path);
307 if (plen == 0) {
308 continue; // Skip the empty path values.
309 }
310 const char lastchar = path[plen - 1];
311 retval = conc_path_file_and_check(buffer, buffer, buflen, path, lastchar, fullfname);
312 if (retval) break;
313 }
314 // Release the storage allocated by split_path.
315 for (int i = 0; i < n; i++) {
316 if (pelements[i] != NULL) {
317 FREE_C_HEAP_ARRAY(char, pelements[i]);
318 }
319 }
320 FREE_C_HEAP_ARRAY(char*, pelements);
321 }
322 } else {
323 // A definite path.
324 const char lastchar = pname[pnamelen-1];
325 retval = conc_path_file_and_check(buffer, buffer, buflen, pname, lastchar, fullfname);
326 }
327 }
328
329 FREE_C_HEAP_ARRAY(char*, fullfname);
330 return retval;
331 }
332
333 // --------------------- sun.misc.Signal (optional) ---------------------
334
335
336 // SIGBREAK is sent by the keyboard to query the VM state
337 #ifndef SIGBREAK
338 #define SIGBREAK SIGQUIT
339 #endif
340
341 // sigexitnum_pd is a platform-specific special signal used for terminating the Signal thread.
342
343
344 static void signal_thread_entry(JavaThread* thread, TRAPS) {
345 os::set_priority(thread, NearMaxPriority);
346 while (true) {
347 int sig;
348 {
349 // FIXME : Currently we have not decided what should be the status
350 // for this java thread blocked here. Once we decide about
351 // that we should fix this.
352 sig = os::signal_wait();
353 }
354 if (sig == os::sigexitnum_pd()) {
355 // Terminate the signal thread
356 return;
357 }
358
359 switch (sig) {
360 case SIGBREAK: {
361 // Check if the signal is a trigger to start the Attach Listener - in that
362 // case don't print stack traces.
363 if (!DisableAttachMechanism && AttachListener::is_init_trigger()) {
364 continue;
365 }
366 // Print stack traces
367 // Any SIGBREAK operations added here should make sure to flush
368 // the output stream (e.g. tty->flush()) after output. See 4803766.
369 // Each module also prints an extra carriage return after its output.
370 VM_PrintThreads op;
371 VMThread::execute(&op);
372 VM_PrintJNI jni_op;
373 VMThread::execute(&jni_op);
374 VM_FindDeadlocks op1(tty);
375 VMThread::execute(&op1);
376 Universe::print_heap_at_SIGBREAK();
377 if (PrintClassHistogram) {
378 VM_GC_HeapInspection op1(tty, true /* force full GC before heap inspection */);
379 VMThread::execute(&op1);
380 }
381 if (JvmtiExport::should_post_data_dump()) {
382 JvmtiExport::post_data_dump();
383 }
384 break;
385 }
386 default: {
387 // Dispatch the signal to java
388 HandleMark hm(THREAD);
389 Klass* klass = SystemDictionary::resolve_or_null(vmSymbols::jdk_internal_misc_Signal(), THREAD);
390 if (klass != NULL) {
391 JavaValue result(T_VOID);
392 JavaCallArguments args;
393 args.push_int(sig);
394 JavaCalls::call_static(
395 &result,
396 klass,
397 vmSymbols::dispatch_name(),
398 vmSymbols::int_void_signature(),
399 &args,
400 THREAD
401 );
402 }
403 if (HAS_PENDING_EXCEPTION) {
404 // tty is initialized early so we don't expect it to be null, but
405 // if it is we can't risk doing an initialization that might
406 // trigger additional out-of-memory conditions
407 if (tty != NULL) {
408 char klass_name[256];
409 char tmp_sig_name[16];
410 const char* sig_name = "UNKNOWN";
411 InstanceKlass::cast(PENDING_EXCEPTION->klass())->
412 name()->as_klass_external_name(klass_name, 256);
413 if (os::exception_name(sig, tmp_sig_name, 16) != NULL)
414 sig_name = tmp_sig_name;
415 warning("Exception %s occurred dispatching signal %s to handler"
416 "- the VM may need to be forcibly terminated",
417 klass_name, sig_name );
418 }
419 CLEAR_PENDING_EXCEPTION;
420 }
421 }
422 }
423 }
424 }
425
426 void os::init_before_ergo() {
427 initialize_initial_active_processor_count();
428 // We need to initialize large page support here because ergonomics takes some
429 // decisions depending on large page support and the calculated large page size.
430 large_page_init();
431
432 // We need to adapt the configured number of stack protection pages given
433 // in 4K pages to the actual os page size. We must do this before setting
434 // up minimal stack sizes etc. in os::init_2().
435 JavaThread::set_stack_red_zone_size (align_up(StackRedPages * 4 * K, vm_page_size()));
436 JavaThread::set_stack_yellow_zone_size (align_up(StackYellowPages * 4 * K, vm_page_size()));
437 JavaThread::set_stack_reserved_zone_size(align_up(StackReservedPages * 4 * K, vm_page_size()));
438 JavaThread::set_stack_shadow_zone_size (align_up(StackShadowPages * 4 * K, vm_page_size()));
439
440 // VM version initialization identifies some characteristics of the
441 // platform that are used during ergonomic decisions.
442 VM_Version::init_before_ergo();
443 }
444
445 void os::initialize_jdk_signal_support(TRAPS) {
446 if (!ReduceSignalUsage) {
447 // Setup JavaThread for processing signals
448 const char thread_name[] = "Signal Dispatcher";
449 Handle string = java_lang_String::create_from_str(thread_name, CHECK);
450
451 // Initialize thread_oop to put it into the system threadGroup
452 Handle thread_group (THREAD, Universe::system_thread_group());
453 Handle thread_oop = JavaCalls::construct_new_instance(SystemDictionary::Thread_klass(),
454 vmSymbols::threadgroup_string_void_signature(),
455 thread_group,
456 string,
457 CHECK);
458
459 Klass* group = SystemDictionary::ThreadGroup_klass();
460 JavaValue result(T_VOID);
461 JavaCalls::call_special(&result,
462 thread_group,
463 group,
464 vmSymbols::add_method_name(),
465 vmSymbols::thread_void_signature(),
466 thread_oop,
467 CHECK);
468
469 { MutexLocker mu(Threads_lock);
470 JavaThread* signal_thread = new JavaThread(&signal_thread_entry);
471
472 // At this point it may be possible that no osthread was created for the
473 // JavaThread due to lack of memory. We would have to throw an exception
474 // in that case. However, since this must work and we do not allow
475 // exceptions anyway, check and abort if this fails.
476 if (signal_thread == NULL || signal_thread->osthread() == NULL) {
477 vm_exit_during_initialization("java.lang.OutOfMemoryError",
478 os::native_thread_creation_failed_msg());
479 }
480
481 java_lang_Thread::set_thread(thread_oop(), signal_thread);
482 java_lang_Thread::set_priority(thread_oop(), NearMaxPriority);
483 java_lang_Thread::set_daemon(thread_oop());
484
485 signal_thread->set_threadObj(thread_oop());
486 Threads::add(signal_thread);
487 Thread::start(signal_thread);
488 }
489 // Handle ^BREAK
490 os::signal(SIGBREAK, os::user_handler());
491 }
492 }
493
494
495 void os::terminate_signal_thread() {
496 if (!ReduceSignalUsage)
497 signal_notify(sigexitnum_pd());
498 }
499
500
501 // --------------------- loading libraries ---------------------
502
503 typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *);
504 extern struct JavaVM_ main_vm;
505
506 static void* _native_java_library = NULL;
507
508 void* os::native_java_library() {
509 if (_native_java_library == NULL) {
510 char buffer[JVM_MAXPATHLEN];
511 char ebuf[1024];
512
513 // Try to load verify dll first. In 1.3 java dll depends on it and is not
514 // always able to find it when the loading executable is outside the JDK.
515 // In order to keep working with 1.2 we ignore any loading errors.
516 if (dll_locate_lib(buffer, sizeof(buffer), Arguments::get_dll_dir(),
517 "verify")) {
518 dll_load(buffer, ebuf, sizeof(ebuf));
519 }
520
521 // Load java dll
522 if (dll_locate_lib(buffer, sizeof(buffer), Arguments::get_dll_dir(),
523 "java")) {
524 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf));
525 }
526 if (_native_java_library == NULL) {
527 vm_exit_during_initialization("Unable to load native library", ebuf);
528 }
529
530 #if defined(__OpenBSD__)
531 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so
532 // ignore errors
533 if (dll_locate_lib(buffer, sizeof(buffer), Arguments::get_dll_dir(),
534 "net")) {
535 dll_load(buffer, ebuf, sizeof(ebuf));
536 }
537 #endif
538 }
539 return _native_java_library;
540 }
541
542 /*
543 * Support for finding Agent_On(Un)Load/Attach<_lib_name> if it exists.
544 * If check_lib == true then we are looking for an
545 * Agent_OnLoad_lib_name or Agent_OnAttach_lib_name function to determine if
546 * this library is statically linked into the image.
547 * If check_lib == false then we will look for the appropriate symbol in the
548 * executable if agent_lib->is_static_lib() == true or in the shared library
549 * referenced by 'handle'.
550 */
551 void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib,
552 const char *syms[], size_t syms_len) {
553 assert(agent_lib != NULL, "sanity check");
554 const char *lib_name;
555 void *handle = agent_lib->os_lib();
556 void *entryName = NULL;
557 char *agent_function_name;
558 size_t i;
559
560 // If checking then use the agent name otherwise test is_static_lib() to
561 // see how to process this lookup
562 lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL);
563 for (i = 0; i < syms_len; i++) {
564 agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path());
565 if (agent_function_name == NULL) {
566 break;
567 }
568 entryName = dll_lookup(handle, agent_function_name);
569 FREE_C_HEAP_ARRAY(char, agent_function_name);
570 if (entryName != NULL) {
571 break;
572 }
573 }
574 return entryName;
575 }
576
577 // See if the passed in agent is statically linked into the VM image.
578 bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
579 size_t syms_len) {
580 void *ret;
581 void *proc_handle;
582 void *save_handle;
583
584 assert(agent_lib != NULL, "sanity check");
585 if (agent_lib->name() == NULL) {
586 return false;
587 }
588 proc_handle = get_default_process_handle();
589 // Check for Agent_OnLoad/Attach_lib_name function
590 save_handle = agent_lib->os_lib();
591 // We want to look in this process' symbol table.
592 agent_lib->set_os_lib(proc_handle);
593 ret = find_agent_function(agent_lib, true, syms, syms_len);
594 if (ret != NULL) {
595 // Found an entry point like Agent_OnLoad_lib_name so we have a static agent
596 agent_lib->set_valid();
597 agent_lib->set_static_lib(true);
598 return true;
599 }
600 agent_lib->set_os_lib(save_handle);
601 return false;
602 }
603
604 // --------------------- heap allocation utilities ---------------------
605
606 char *os::strdup(const char *str, MEMFLAGS flags) {
607 size_t size = strlen(str);
608 char *dup_str = (char *)malloc(size + 1, flags);
609 if (dup_str == NULL) return NULL;
610 strcpy(dup_str, str);
611 return dup_str;
612 }
613
614 char* os::strdup_check_oom(const char* str, MEMFLAGS flags) {
615 char* p = os::strdup(str, flags);
616 if (p == NULL) {
617 vm_exit_out_of_memory(strlen(str) + 1, OOM_MALLOC_ERROR, "os::strdup_check_oom");
618 }
619 return p;
620 }
621
622
623 #define paranoid 0 /* only set to 1 if you suspect checking code has bug */
624
625 #ifdef ASSERT
626
627 static void verify_memory(void* ptr) {
628 GuardedMemory guarded(ptr);
629 if (!guarded.verify_guards()) {
630 LogTarget(Warning, malloc, free) lt;
631 ResourceMark rm;
632 LogStream ls(lt);
633 ls.print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees);
634 ls.print_cr("## memory stomp:");
635 guarded.print_on(&ls);
636 fatal("memory stomping error");
637 }
638 }
639
640 #endif
641
642 //
643 // This function supports testing of the malloc out of memory
644 // condition without really running the system out of memory.
645 //
646 static bool has_reached_max_malloc_test_peak(size_t alloc_size) {
647 if (MallocMaxTestWords > 0) {
648 size_t words = (alloc_size / BytesPerWord);
649
650 if ((cur_malloc_words + words) > MallocMaxTestWords) {
651 return true;
652 }
653 Atomic::add(words, &cur_malloc_words);
654 }
655 return false;
656 }
657
658 void* os::malloc(size_t size, MEMFLAGS flags) {
659 return os::malloc(size, flags, CALLER_PC);
660 }
661
662 void* os::malloc(size_t size, MEMFLAGS memflags, const NativeCallStack& stack) {
663 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
664 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
665
666 // Since os::malloc can be called when the libjvm.{dll,so} is
667 // first loaded and we don't have a thread yet we must accept NULL also here.
668 assert(!os::ThreadCrashProtection::is_crash_protected(Thread::current_or_null()),
669 "malloc() not allowed when crash protection is set");
670
671 if (size == 0) {
672 // return a valid pointer if size is zero
673 // if NULL is returned the calling functions assume out of memory.
674 size = 1;
675 }
676
677 // NMT support
678 NMT_TrackingLevel level = MemTracker::tracking_level();
679 size_t nmt_header_size = MemTracker::malloc_header_size(level);
680
681 #ifndef ASSERT
682 const size_t alloc_size = size + nmt_header_size;
683 #else
684 const size_t alloc_size = GuardedMemory::get_total_size(size + nmt_header_size);
685 if (size + nmt_header_size > alloc_size) { // Check for rollover.
686 return NULL;
687 }
688 #endif
689
690 // For the test flag -XX:MallocMaxTestWords
691 if (has_reached_max_malloc_test_peak(size)) {
692 return NULL;
693 }
694
695 u_char* ptr;
696 ptr = (u_char*)::malloc(alloc_size);
697
698 #ifdef ASSERT
699 if (ptr == NULL) {
700 return NULL;
701 }
702 // Wrap memory with guard
703 GuardedMemory guarded(ptr, size + nmt_header_size);
704 ptr = guarded.get_user_ptr();
705 #endif
706 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) {
707 log_warning(malloc, free)("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr));
708 breakpoint();
709 }
710 debug_only(if (paranoid) verify_memory(ptr));
711
712 // we do not track guard memory
713 return MemTracker::record_malloc((address)ptr, size, memflags, stack, level);
714 }
715
716 void* os::realloc(void *memblock, size_t size, MEMFLAGS flags) {
717 return os::realloc(memblock, size, flags, CALLER_PC);
718 }
719
720 void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, const NativeCallStack& stack) {
721
722 // For the test flag -XX:MallocMaxTestWords
723 if (has_reached_max_malloc_test_peak(size)) {
724 return NULL;
725 }
726
727 if (size == 0) {
728 // return a valid pointer if size is zero
729 // if NULL is returned the calling functions assume out of memory.
730 size = 1;
731 }
732
733 #ifndef ASSERT
734 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
735 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
736 // NMT support
737 void* membase = MemTracker::record_free(memblock);
738 NMT_TrackingLevel level = MemTracker::tracking_level();
739 size_t nmt_header_size = MemTracker::malloc_header_size(level);
740 void* ptr = ::realloc(membase, size + nmt_header_size);
741 return MemTracker::record_malloc(ptr, size, memflags, stack, level);
742 #else
743 if (memblock == NULL) {
744 return os::malloc(size, memflags, stack);
745 }
746 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
747 log_warning(malloc, free)("os::realloc caught " PTR_FORMAT, p2i(memblock));
748 breakpoint();
749 }
750 // NMT support
751 void* membase = MemTracker::malloc_base(memblock);
752 verify_memory(membase);
753 // always move the block
754 void* ptr = os::malloc(size, memflags, stack);
755 // Copy to new memory if malloc didn't fail
756 if (ptr != NULL ) {
757 GuardedMemory guarded(MemTracker::malloc_base(memblock));
758 // Guard's user data contains NMT header
759 size_t memblock_size = guarded.get_user_size() - MemTracker::malloc_header_size(memblock);
760 memcpy(ptr, memblock, MIN2(size, memblock_size));
761 if (paranoid) verify_memory(MemTracker::malloc_base(ptr));
762 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) {
763 log_warning(malloc, free)("os::realloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, p2i(ptr));
764 breakpoint();
765 }
766 os::free(memblock);
767 }
768 return ptr;
769 #endif
770 }
771
772
773 void os::free(void *memblock) {
774 NOT_PRODUCT(inc_stat_counter(&num_frees, 1));
775 #ifdef ASSERT
776 if (memblock == NULL) return;
777 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
778 log_warning(malloc, free)("os::free caught " PTR_FORMAT, p2i(memblock));
779 breakpoint();
780 }
781 void* membase = MemTracker::record_free(memblock);
782 verify_memory(membase);
783
784 GuardedMemory guarded(membase);
785 size_t size = guarded.get_user_size();
786 inc_stat_counter(&free_bytes, size);
787 membase = guarded.release_for_freeing();
788 ::free(membase);
789 #else
790 void* membase = MemTracker::record_free(memblock);
791 ::free(membase);
792 #endif
793 }
794
795 void os::init_random(unsigned int initval) {
796 _rand_seed = initval;
797 }
798
799
800 static int random_helper(unsigned int rand_seed) {
801 /* standard, well-known linear congruential random generator with
802 * next_rand = (16807*seed) mod (2**31-1)
803 * see
804 * (1) "Random Number Generators: Good Ones Are Hard to Find",
805 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988),
806 * (2) "Two Fast Implementations of the 'Minimal Standard' Random
807 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88.
808 */
809 const unsigned int a = 16807;
810 const unsigned int m = 2147483647;
811 const int q = m / a; assert(q == 127773, "weird math");
812 const int r = m % a; assert(r == 2836, "weird math");
813
814 // compute az=2^31p+q
815 unsigned int lo = a * (rand_seed & 0xFFFF);
816 unsigned int hi = a * (rand_seed >> 16);
817 lo += (hi & 0x7FFF) << 16;
818
819 // if q overflowed, ignore the overflow and increment q
820 if (lo > m) {
821 lo &= m;
822 ++lo;
823 }
824 lo += hi >> 15;
825
826 // if (p+q) overflowed, ignore the overflow and increment (p+q)
827 if (lo > m) {
828 lo &= m;
829 ++lo;
830 }
831 return lo;
832 }
833
834 int os::random() {
835 // Make updating the random seed thread safe.
836 while (true) {
837 unsigned int seed = _rand_seed;
838 unsigned int rand = random_helper(seed);
839 if (Atomic::cmpxchg(rand, &_rand_seed, seed) == seed) {
840 return static_cast<int>(rand);
841 }
842 }
843 }
844
845 // The INITIALIZED state is distinguished from the SUSPENDED state because the
846 // conditions in which a thread is first started are different from those in which
847 // a suspension is resumed. These differences make it hard for us to apply the
848 // tougher checks when starting threads that we want to do when resuming them.
849 // However, when start_thread is called as a result of Thread.start, on a Java
850 // thread, the operation is synchronized on the Java Thread object. So there
851 // cannot be a race to start the thread and hence for the thread to exit while
852 // we are working on it. Non-Java threads that start Java threads either have
853 // to do so in a context in which races are impossible, or should do appropriate
854 // locking.
855
856 void os::start_thread(Thread* thread) {
857 // guard suspend/resume
858 MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag);
859 OSThread* osthread = thread->osthread();
860 osthread->set_state(RUNNABLE);
861 pd_start_thread(thread);
862 }
863
864 void os::abort(bool dump_core) {
865 abort(dump_core && CreateCoredumpOnCrash, NULL, NULL);
866 }
867
868 //---------------------------------------------------------------------------
869 // Helper functions for fatal error handler
870
871 void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) {
872 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking");
873
874 int cols = 0;
875 int cols_per_line = 0;
876 switch (unitsize) {
877 case 1: cols_per_line = 16; break;
878 case 2: cols_per_line = 8; break;
879 case 4: cols_per_line = 4; break;
880 case 8: cols_per_line = 2; break;
881 default: return;
882 }
883
884 address p = start;
885 st->print(PTR_FORMAT ": ", p2i(start));
886 while (p < end) {
887 switch (unitsize) {
888 case 1: st->print("%02x", *(u1*)p); break;
889 case 2: st->print("%04x", *(u2*)p); break;
890 case 4: st->print("%08x", *(u4*)p); break;
891 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break;
892 }
893 p += unitsize;
894 cols++;
895 if (cols >= cols_per_line && p < end) {
896 cols = 0;
897 st->cr();
898 st->print(PTR_FORMAT ": ", p2i(p));
899 } else {
900 st->print(" ");
901 }
902 }
903 st->cr();
904 }
905
906 void os::print_environment_variables(outputStream* st, const char** env_list) {
907 if (env_list) {
908 st->print_cr("Environment Variables:");
909
910 for (int i = 0; env_list[i] != NULL; i++) {
911 char *envvar = ::getenv(env_list[i]);
912 if (envvar != NULL) {
913 st->print("%s", env_list[i]);
914 st->print("=");
915 st->print_cr("%s", envvar);
916 }
917 }
918 }
919 }
920
921 void os::print_cpu_info(outputStream* st, char* buf, size_t buflen) {
922 // cpu
923 st->print("CPU:");
924 st->print("total %d", os::processor_count());
925 // It's not safe to query number of active processors after crash
926 // st->print("(active %d)", os::active_processor_count()); but we can
927 // print the initial number of active processors.
928 // We access the raw value here because the assert in the accessor will
929 // fail if the crash occurs before initialization of this value.
930 st->print(" (initial active %d)", _initial_active_processor_count);
931 st->print(" %s", VM_Version::features_string());
932 st->cr();
933 pd_print_cpu_info(st, buf, buflen);
934 }
935
936 // Print a one line string summarizing the cpu, number of cores, memory, and operating system version
937 void os::print_summary_info(outputStream* st, char* buf, size_t buflen) {
938 st->print("Host: ");
939 #ifndef PRODUCT
940 if (get_host_name(buf, buflen)) {
941 st->print("%s, ", buf);
942 }
943 #endif // PRODUCT
944 get_summary_cpu_info(buf, buflen);
945 st->print("%s, ", buf);
946 size_t mem = physical_memory()/G;
947 if (mem == 0) { // for low memory systems
948 mem = physical_memory()/M;
949 st->print("%d cores, " SIZE_FORMAT "M, ", processor_count(), mem);
950 } else {
951 st->print("%d cores, " SIZE_FORMAT "G, ", processor_count(), mem);
952 }
953 get_summary_os_info(buf, buflen);
954 st->print_raw(buf);
955 st->cr();
956 }
957
958 void os::print_date_and_time(outputStream *st, char* buf, size_t buflen) {
959 const int secs_per_day = 86400;
960 const int secs_per_hour = 3600;
961 const int secs_per_min = 60;
962
963 time_t tloc;
964 (void)time(&tloc);
965 char* timestring = ctime(&tloc); // ctime adds newline.
966 // edit out the newline
967 char* nl = strchr(timestring, '\n');
968 if (nl != NULL) {
969 *nl = '\0';
970 }
971
972 struct tm tz;
973 if (localtime_pd(&tloc, &tz) != NULL) {
974 ::strftime(buf, buflen, "%Z", &tz);
975 st->print("Time: %s %s", timestring, buf);
976 } else {
977 st->print("Time: %s", timestring);
978 }
979
980 double t = os::elapsedTime();
981 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in
982 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int
983 // before printf. We lost some precision, but who cares?
984 int eltime = (int)t; // elapsed time in seconds
985
986 // print elapsed time in a human-readable format:
987 int eldays = eltime / secs_per_day;
988 int day_secs = eldays * secs_per_day;
989 int elhours = (eltime - day_secs) / secs_per_hour;
990 int hour_secs = elhours * secs_per_hour;
991 int elmins = (eltime - day_secs - hour_secs) / secs_per_min;
992 int minute_secs = elmins * secs_per_min;
993 int elsecs = (eltime - day_secs - hour_secs - minute_secs);
994 st->print_cr(" elapsed time: %d seconds (%dd %dh %dm %ds)", eltime, eldays, elhours, elmins, elsecs);
995 }
996
997
998 // Check if pointer can be read from (4-byte read access).
999 // Helps to prove validity of a not-NULL pointer.
1000 // Returns true in very early stages of VM life when stub is not yet generated.
1001 #define SAFEFETCH_DEFAULT true
1002 bool os::is_readable_pointer(const void* p) {
1003 if (!CanUseSafeFetch32()) {
1004 return SAFEFETCH_DEFAULT;
1005 }
1006 int* const aligned = (int*) align_down((intptr_t)p, 4);
1007 int cafebabe = 0xcafebabe; // tester value 1
1008 int deadbeef = 0xdeadbeef; // tester value 2
1009 return (SafeFetch32(aligned, cafebabe) != cafebabe) || (SafeFetch32(aligned, deadbeef) != deadbeef);
1010 }
1011
1012 bool os::is_readable_range(const void* from, const void* to) {
1013 for (address p = align_down((address)from, min_page_size()); p < to; p += min_page_size()) {
1014 if (!is_readable_pointer(p)) {
1015 return false;
1016 }
1017 }
1018 return true;
1019 }
1020
1021
1022 // moved from debug.cpp (used to be find()) but still called from there
1023 // The verbose parameter is only set by the debug code in one case
1024 void os::print_location(outputStream* st, intptr_t x, bool verbose) {
1025 address addr = (address)x;
1026 // Handle NULL first, so later checks don't need to protect against it.
1027 if (addr == NULL) {
1028 st->print_cr("0x0 is NULL");
1029 return;
1030 }
1031
1032 // Check if addr points into a code blob.
1033 CodeBlob* b = CodeCache::find_blob_unsafe(addr);
1034 if (b != NULL) {
1035 b->dump_for_addr(addr, st, verbose);
1036 return;
1037 }
1038
1039 // Check if addr points into Java heap.
1040 if (Universe::heap()->is_in(addr)) {
1041 oop o = oopDesc::oop_or_null(addr);
1042 if (o != NULL) {
1043 if ((HeapWord*)o == (HeapWord*)addr) {
1044 st->print(INTPTR_FORMAT " is an oop: ", p2i(addr));
1045 } else {
1046 st->print(INTPTR_FORMAT " is pointing into object: " , p2i(addr));
1047 }
1048 o->print_on(st);
1049 return;
1050 }
1051 } else if (Universe::heap()->is_in_reserved(addr)) {
1052 st->print_cr(INTPTR_FORMAT " is an unallocated location in the heap", p2i(addr));
1053 return;
1054 }
1055
1056 // Compressed oop needs to be decoded first.
1057 #ifdef _LP64
1058 if (UseCompressedOops && ((uintptr_t)addr &~ (uintptr_t)max_juint) == 0) {
1059 narrowOop narrow_oop = (narrowOop)(uintptr_t)addr;
1060 oop o = oopDesc::decode_oop_raw(narrow_oop);
1061
1062 if (oopDesc::is_valid(o)) {
1063 st->print(UINT32_FORMAT " is a compressed pointer to object: ", narrow_oop);
1064 o->print_on(st);
1065 return;
1066 }
1067 }
1068 #endif
1069
1070 bool accessible = is_readable_pointer(addr);
1071
1072 // Check if addr is a JNI handle.
1073 if (align_down((intptr_t)addr, sizeof(intptr_t)) != 0 && accessible) {
1074 if (JNIHandles::is_global_handle((jobject) addr)) {
1075 st->print_cr(INTPTR_FORMAT " is a global jni handle", p2i(addr));
1076 return;
1077 }
1078 if (JNIHandles::is_weak_global_handle((jobject) addr)) {
1079 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", p2i(addr));
1080 return;
1081 }
1082 #ifndef PRODUCT
1083 // we don't keep the block list in product mode
1084 if (JNIHandles::is_local_handle((jobject) addr)) {
1085 st->print_cr(INTPTR_FORMAT " is a local jni handle", p2i(addr));
1086 return;
1087 }
1088 #endif
1089 }
1090
1091 // Check if addr belongs to a Java thread.
1092 for (JavaThreadIteratorWithHandle jtiwh; JavaThread *thread = jtiwh.next(); ) {
1093 // If the addr is a java thread print information about that.
1094 if (addr == (address)thread) {
1095 if (verbose) {
1096 thread->print_on(st);
1097 } else {
1098 st->print_cr(INTPTR_FORMAT " is a thread", p2i(addr));
1099 }
1100 return;
1101 }
1102 // If the addr is in the stack region for this thread then report that
1103 // and print thread info
1104 if (thread->on_local_stack(addr)) {
1105 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: "
1106 INTPTR_FORMAT, p2i(addr), p2i(thread));
1107 if (verbose) thread->print_on(st);
1108 return;
1109 }
1110 }
1111
1112 // Check if in metaspace and print types that have vptrs
1113 if (Metaspace::contains(addr)) {
1114 if (Klass::is_valid((Klass*)addr)) {
1115 st->print_cr(INTPTR_FORMAT " is a pointer to class: ", p2i(addr));
1116 ((Klass*)addr)->print_on(st);
1117 } else if (Method::is_valid_method((const Method*)addr)) {
1118 ((Method*)addr)->print_value_on(st);
1119 st->cr();
1120 } else {
1121 // Use addr->print() from the debugger instead (not here)
1122 st->print_cr(INTPTR_FORMAT " is pointing into metadata", p2i(addr));
1123 }
1124 return;
1125 }
1126
1127 // Compressed klass needs to be decoded first.
1128 #ifdef _LP64
1129 if (UseCompressedClassPointers && ((uintptr_t)addr &~ (uintptr_t)max_juint) == 0) {
1130 narrowKlass narrow_klass = (narrowKlass)(uintptr_t)addr;
1131 Klass* k = Klass::decode_klass_raw(narrow_klass);
1132
1133 if (Klass::is_valid(k)) {
1134 st->print_cr(UINT32_FORMAT " is a compressed pointer to class: " INTPTR_FORMAT, narrow_klass, p2i((HeapWord*)k));
1135 k->print_on(st);
1136 return;
1137 }
1138 }
1139 #endif
1140
1141 // Try an OS specific find
1142 if (os::find(addr, st)) {
1143 return;
1144 }
1145
1146 if (accessible) {
1147 st->print(INTPTR_FORMAT " points into unknown readable memory:", p2i(addr));
1148 for (address p = addr; p < align_up(addr + 1, sizeof(intptr_t)); ++p) {
1149 st->print(" %02x", *(u1*)p);
1150 }
1151 st->cr();
1152 return;
1153 }
1154
1155 st->print_cr(INTPTR_FORMAT " is an unknown value", p2i(addr));
1156 }
1157
1158 // Looks like all platforms can use the same function to check if C
1159 // stack is walkable beyond current frame. The check for fp() is not
1160 // necessary on Sparc, but it's harmless.
1161 bool os::is_first_C_frame(frame* fr) {
1162 // Load up sp, fp, sender sp and sender fp, check for reasonable values.
1163 // Check usp first, because if that's bad the other accessors may fault
1164 // on some architectures. Ditto ufp second, etc.
1165 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1);
1166 // sp on amd can be 32 bit aligned.
1167 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1);
1168
1169 uintptr_t usp = (uintptr_t)fr->sp();
1170 if ((usp & sp_align_mask) != 0) return true;
1171
1172 uintptr_t ufp = (uintptr_t)fr->fp();
1173 if ((ufp & fp_align_mask) != 0) return true;
1174
1175 uintptr_t old_sp = (uintptr_t)fr->sender_sp();
1176 if ((old_sp & sp_align_mask) != 0) return true;
1177 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true;
1178
1179 uintptr_t old_fp = (uintptr_t)fr->link();
1180 if ((old_fp & fp_align_mask) != 0) return true;
1181 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true;
1182
1183 // stack grows downwards; if old_fp is below current fp or if the stack
1184 // frame is too large, either the stack is corrupted or fp is not saved
1185 // on stack (i.e. on x86, ebp may be used as general register). The stack
1186 // is not walkable beyond current frame.
1187 if (old_fp < ufp) return true;
1188 if (old_fp - ufp > 64 * K) return true;
1189
1190 return false;
1191 }
1192
1193
1194 // Set up the boot classpath.
1195
1196 char* os::format_boot_path(const char* format_string,
1197 const char* home,
1198 int home_len,
1199 char fileSep,
1200 char pathSep) {
1201 assert((fileSep == '/' && pathSep == ':') ||
1202 (fileSep == '\\' && pathSep == ';'), "unexpected separator chars");
1203
1204 // Scan the format string to determine the length of the actual
1205 // boot classpath, and handle platform dependencies as well.
1206 int formatted_path_len = 0;
1207 const char* p;
1208 for (p = format_string; *p != 0; ++p) {
1209 if (*p == '%') formatted_path_len += home_len - 1;
1210 ++formatted_path_len;
1211 }
1212
1213 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal);
1214 if (formatted_path == NULL) {
1215 return NULL;
1216 }
1217
1218 // Create boot classpath from format, substituting separator chars and
1219 // java home directory.
1220 char* q = formatted_path;
1221 for (p = format_string; *p != 0; ++p) {
1222 switch (*p) {
1223 case '%':
1224 strcpy(q, home);
1225 q += home_len;
1226 break;
1227 case '/':
1228 *q++ = fileSep;
1229 break;
1230 case ':':
1231 *q++ = pathSep;
1232 break;
1233 default:
1234 *q++ = *p;
1235 }
1236 }
1237 *q = '\0';
1238
1239 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched");
1240 return formatted_path;
1241 }
1242
1243 // This function is a proxy to fopen, it tries to add a non standard flag ('e' or 'N')
1244 // that ensures automatic closing of the file on exec. If it can not find support in
1245 // the underlying c library, it will make an extra system call (fcntl) to ensure automatic
1246 // closing of the file on exec.
1247 FILE* os::fopen(const char* path, const char* mode) {
1248 char modified_mode[20];
1249 assert(strlen(mode) + 1 < sizeof(modified_mode), "mode chars plus one extra must fit in buffer");
1250 sprintf(modified_mode, "%s" LINUX_ONLY("e") BSD_ONLY("e") WINDOWS_ONLY("N"), mode);
1251 FILE* file = ::fopen(path, modified_mode);
1252
1253 #if !(defined LINUX || defined BSD || defined _WINDOWS)
1254 // assume fcntl FD_CLOEXEC support as a backup solution when 'e' or 'N'
1255 // is not supported as mode in fopen
1256 if (file != NULL) {
1257 int fd = fileno(file);
1258 if (fd != -1) {
1259 int fd_flags = fcntl(fd, F_GETFD);
1260 if (fd_flags != -1) {
1261 fcntl(fd, F_SETFD, fd_flags | FD_CLOEXEC);
1262 }
1263 }
1264 }
1265 #endif
1266
1267 return file;
1268 }
1269
1270 bool os::set_boot_path(char fileSep, char pathSep) {
1271 const char* home = Arguments::get_java_home();
1272 int home_len = (int)strlen(home);
1273
1274 struct stat st;
1275
1276 // modular image if "modules" jimage exists
1277 char* jimage = format_boot_path("%/lib/" MODULES_IMAGE_NAME, home, home_len, fileSep, pathSep);
1278 if (jimage == NULL) return false;
1279 bool has_jimage = (os::stat(jimage, &st) == 0);
1280 if (has_jimage) {
1281 Arguments::set_sysclasspath(jimage, true);
1282 FREE_C_HEAP_ARRAY(char, jimage);
1283 return true;
1284 }
1285 FREE_C_HEAP_ARRAY(char, jimage);
1286
1287 // check if developer build with exploded modules
1288 char* base_classes = format_boot_path("%/modules/" JAVA_BASE_NAME, home, home_len, fileSep, pathSep);
1289 if (base_classes == NULL) return false;
1290 if (os::stat(base_classes, &st) == 0) {
1291 Arguments::set_sysclasspath(base_classes, false);
1292 FREE_C_HEAP_ARRAY(char, base_classes);
1293 return true;
1294 }
1295 FREE_C_HEAP_ARRAY(char, base_classes);
1296
1297 return false;
1298 }
1299
1300 /*
1301 * Splits a path, based on its separator, the number of
1302 * elements is returned back in n.
1303 * It is the callers responsibility to:
1304 * a> check the value of n, and n may be 0.
1305 * b> ignore any empty path elements
1306 * c> free up the data.
1307 */
1308 char** os::split_path(const char* path, int* n) {
1309 *n = 0;
1310 if (path == NULL || strlen(path) == 0) {
1311 return NULL;
1312 }
1313 const char psepchar = *os::path_separator();
1314 char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal);
1315 if (inpath == NULL) {
1316 return NULL;
1317 }
1318 strcpy(inpath, path);
1319 int count = 1;
1320 char* p = strchr(inpath, psepchar);
1321 // Get a count of elements to allocate memory
1322 while (p != NULL) {
1323 count++;
1324 p++;
1325 p = strchr(p, psepchar);
1326 }
1327 char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count, mtInternal);
1328 if (opath == NULL) {
1329 return NULL;
1330 }
1331
1332 // do the actual splitting
1333 p = inpath;
1334 for (int i = 0 ; i < count ; i++) {
1335 size_t len = strcspn(p, os::path_separator());
1336 if (len > JVM_MAXPATHLEN) {
1337 return NULL;
1338 }
1339 // allocate the string and add terminator storage
1340 char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
1341 if (s == NULL) {
1342 return NULL;
1343 }
1344 strncpy(s, p, len);
1345 s[len] = '\0';
1346 opath[i] = s;
1347 p += len + 1;
1348 }
1349 FREE_C_HEAP_ARRAY(char, inpath);
1350 *n = count;
1351 return opath;
1352 }
1353
1354 void os::set_memory_serialize_page(address page) {
1355 int count = log2_intptr(sizeof(class JavaThread)) - log2_intptr(64);
1356 _mem_serialize_page = (volatile int32_t *)page;
1357 // We initialize the serialization page shift count here
1358 // We assume a cache line size of 64 bytes
1359 assert(SerializePageShiftCount == count, "JavaThread size changed; "
1360 "SerializePageShiftCount constant should be %d", count);
1361 set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t)));
1362 }
1363
1364 static volatile intptr_t SerializePageLock = 0;
1365
1366 // This method is called from signal handler when SIGSEGV occurs while the current
1367 // thread tries to store to the "read-only" memory serialize page during state
1368 // transition.
1369 void os::block_on_serialize_page_trap() {
1370 log_debug(safepoint)("Block until the serialize page permission restored");
1371
1372 // When VMThread is holding the SerializePageLock during modifying the
1373 // access permission of the memory serialize page, the following call
1374 // will block until the permission of that page is restored to rw.
1375 // Generally, it is unsafe to manipulate locks in signal handlers, but in
1376 // this case, it's OK as the signal is synchronous and we know precisely when
1377 // it can occur.
1378 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page");
1379 Thread::muxRelease(&SerializePageLock);
1380 }
1381
1382 // Serialize all thread state variables
1383 void os::serialize_thread_states() {
1384 // On some platforms such as Solaris & Linux, the time duration of the page
1385 // permission restoration is observed to be much longer than expected due to
1386 // scheduler starvation problem etc. To avoid the long synchronization
1387 // time and expensive page trap spinning, 'SerializePageLock' is used to block
1388 // the mutator thread if such case is encountered. See bug 6546278 for details.
1389 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states");
1390 os::protect_memory((char *)os::get_memory_serialize_page(),
1391 os::vm_page_size(), MEM_PROT_READ);
1392 os::protect_memory((char *)os::get_memory_serialize_page(),
1393 os::vm_page_size(), MEM_PROT_RW);
1394 Thread::muxRelease(&SerializePageLock);
1395 }
1396
1397 // Returns true if the current stack pointer is above the stack shadow
1398 // pages, false otherwise.
1399 bool os::stack_shadow_pages_available(Thread *thread, const methodHandle& method, address sp) {
1400 if (!thread->is_Java_thread()) return false;
1401 // Check if we have StackShadowPages above the yellow zone. This parameter
1402 // is dependent on the depth of the maximum VM call stack possible from
1403 // the handler for stack overflow. 'instanceof' in the stack overflow
1404 // handler or a println uses at least 8k stack of VM and native code
1405 // respectively.
1406 const int framesize_in_bytes =
1407 Interpreter::size_top_interpreter_activation(method()) * wordSize;
1408
1409 address limit = ((JavaThread*)thread)->stack_end() +
1410 (JavaThread::stack_guard_zone_size() + JavaThread::stack_shadow_zone_size());
1411
1412 return sp > (limit + framesize_in_bytes);
1413 }
1414
1415 size_t os::page_size_for_region(size_t region_size, size_t min_pages, bool must_be_aligned) {
1416 assert(min_pages > 0, "sanity");
1417 if (UseLargePages) {
1418 const size_t max_page_size = region_size / min_pages;
1419
1420 for (size_t i = 0; _page_sizes[i] != 0; ++i) {
1421 const size_t page_size = _page_sizes[i];
1422 if (page_size <= max_page_size) {
1423 if (!must_be_aligned || is_aligned(region_size, page_size)) {
1424 return page_size;
1425 }
1426 }
1427 }
1428 }
1429
1430 return vm_page_size();
1431 }
1432
1433 size_t os::page_size_for_region_aligned(size_t region_size, size_t min_pages) {
1434 return page_size_for_region(region_size, min_pages, true);
1435 }
1436
1437 size_t os::page_size_for_region_unaligned(size_t region_size, size_t min_pages) {
1438 return page_size_for_region(region_size, min_pages, false);
1439 }
1440
1441 static const char* errno_to_string (int e, bool short_text) {
1442 #define ALL_SHARED_ENUMS(X) \
1443 X(E2BIG, "Argument list too long") \
1444 X(EACCES, "Permission denied") \
1445 X(EADDRINUSE, "Address in use") \
1446 X(EADDRNOTAVAIL, "Address not available") \
1447 X(EAFNOSUPPORT, "Address family not supported") \
1448 X(EAGAIN, "Resource unavailable, try again") \
1449 X(EALREADY, "Connection already in progress") \
1450 X(EBADF, "Bad file descriptor") \
1451 X(EBADMSG, "Bad message") \
1452 X(EBUSY, "Device or resource busy") \
1453 X(ECANCELED, "Operation canceled") \
1454 X(ECHILD, "No child processes") \
1455 X(ECONNABORTED, "Connection aborted") \
1456 X(ECONNREFUSED, "Connection refused") \
1457 X(ECONNRESET, "Connection reset") \
1458 X(EDEADLK, "Resource deadlock would occur") \
1459 X(EDESTADDRREQ, "Destination address required") \
1460 X(EDOM, "Mathematics argument out of domain of function") \
1461 X(EEXIST, "File exists") \
1462 X(EFAULT, "Bad address") \
1463 X(EFBIG, "File too large") \
1464 X(EHOSTUNREACH, "Host is unreachable") \
1465 X(EIDRM, "Identifier removed") \
1466 X(EILSEQ, "Illegal byte sequence") \
1467 X(EINPROGRESS, "Operation in progress") \
1468 X(EINTR, "Interrupted function") \
1469 X(EINVAL, "Invalid argument") \
1470 X(EIO, "I/O error") \
1471 X(EISCONN, "Socket is connected") \
1472 X(EISDIR, "Is a directory") \
1473 X(ELOOP, "Too many levels of symbolic links") \
1474 X(EMFILE, "Too many open files") \
1475 X(EMLINK, "Too many links") \
1476 X(EMSGSIZE, "Message too large") \
1477 X(ENAMETOOLONG, "Filename too long") \
1478 X(ENETDOWN, "Network is down") \
1479 X(ENETRESET, "Connection aborted by network") \
1480 X(ENETUNREACH, "Network unreachable") \
1481 X(ENFILE, "Too many files open in system") \
1482 X(ENOBUFS, "No buffer space available") \
1483 X(ENODATA, "No message is available on the STREAM head read queue") \
1484 X(ENODEV, "No such device") \
1485 X(ENOENT, "No such file or directory") \
1486 X(ENOEXEC, "Executable file format error") \
1487 X(ENOLCK, "No locks available") \
1488 X(ENOLINK, "Reserved") \
1489 X(ENOMEM, "Not enough space") \
1490 X(ENOMSG, "No message of the desired type") \
1491 X(ENOPROTOOPT, "Protocol not available") \
1492 X(ENOSPC, "No space left on device") \
1493 X(ENOSR, "No STREAM resources") \
1494 X(ENOSTR, "Not a STREAM") \
1495 X(ENOSYS, "Function not supported") \
1496 X(ENOTCONN, "The socket is not connected") \
1497 X(ENOTDIR, "Not a directory") \
1498 X(ENOTEMPTY, "Directory not empty") \
1499 X(ENOTSOCK, "Not a socket") \
1500 X(ENOTSUP, "Not supported") \
1501 X(ENOTTY, "Inappropriate I/O control operation") \
1502 X(ENXIO, "No such device or address") \
1503 X(EOPNOTSUPP, "Operation not supported on socket") \
1504 X(EOVERFLOW, "Value too large to be stored in data type") \
1505 X(EPERM, "Operation not permitted") \
1506 X(EPIPE, "Broken pipe") \
1507 X(EPROTO, "Protocol error") \
1508 X(EPROTONOSUPPORT, "Protocol not supported") \
1509 X(EPROTOTYPE, "Protocol wrong type for socket") \
1510 X(ERANGE, "Result too large") \
1511 X(EROFS, "Read-only file system") \
1512 X(ESPIPE, "Invalid seek") \
1513 X(ESRCH, "No such process") \
1514 X(ETIME, "Stream ioctl() timeout") \
1515 X(ETIMEDOUT, "Connection timed out") \
1516 X(ETXTBSY, "Text file busy") \
1517 X(EWOULDBLOCK, "Operation would block") \
1518 X(EXDEV, "Cross-device link")
1519
1520 #define DEFINE_ENTRY(e, text) { e, #e, text },
1521
1522 static const struct {
1523 int v;
1524 const char* short_text;
1525 const char* long_text;
1526 } table [] = {
1527
1528 ALL_SHARED_ENUMS(DEFINE_ENTRY)
1529
1530 // The following enums are not defined on all platforms.
1531 #ifdef ESTALE
1532 DEFINE_ENTRY(ESTALE, "Reserved")
1533 #endif
1534 #ifdef EDQUOT
1535 DEFINE_ENTRY(EDQUOT, "Reserved")
1536 #endif
1537 #ifdef EMULTIHOP
1538 DEFINE_ENTRY(EMULTIHOP, "Reserved")
1539 #endif
1540
1541 // End marker.
1542 { -1, "Unknown errno", "Unknown error" }
1543
1544 };
1545
1546 #undef DEFINE_ENTRY
1547 #undef ALL_FLAGS
1548
1549 int i = 0;
1550 while (table[i].v != -1 && table[i].v != e) {
1551 i ++;
1552 }
1553
1554 return short_text ? table[i].short_text : table[i].long_text;
1555
1556 }
1557
1558 const char* os::strerror(int e) {
1559 return errno_to_string(e, false);
1560 }
1561
1562 const char* os::errno_name(int e) {
1563 return errno_to_string(e, true);
1564 }
1565
1566 void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count) {
1567 LogTarget(Info, pagesize) log;
1568 if (log.is_enabled()) {
1569 LogStream out(log);
1570
1571 out.print("%s: ", str);
1572 for (int i = 0; i < count; ++i) {
1573 out.print(" " SIZE_FORMAT, page_sizes[i]);
1574 }
1575 out.cr();
1576 }
1577 }
1578
1579 #define trace_page_size_params(size) byte_size_in_exact_unit(size), exact_unit_for_byte_size(size)
1580
1581 void os::trace_page_sizes(const char* str,
1582 const size_t region_min_size,
1583 const size_t region_max_size,
1584 const size_t page_size,
1585 const char* base,
1586 const size_t size) {
1587
1588 log_info(pagesize)("%s: "
1589 " min=" SIZE_FORMAT "%s"
1590 " max=" SIZE_FORMAT "%s"
1591 " base=" PTR_FORMAT
1592 " page_size=" SIZE_FORMAT "%s"
1593 " size=" SIZE_FORMAT "%s",
1594 str,
1595 trace_page_size_params(region_min_size),
1596 trace_page_size_params(region_max_size),
1597 p2i(base),
1598 trace_page_size_params(page_size),
1599 trace_page_size_params(size));
1600 }
1601
1602 void os::trace_page_sizes_for_requested_size(const char* str,
1603 const size_t requested_size,
1604 const size_t page_size,
1605 const size_t alignment,
1606 const char* base,
1607 const size_t size) {
1608
1609 log_info(pagesize)("%s:"
1610 " req_size=" SIZE_FORMAT "%s"
1611 " base=" PTR_FORMAT
1612 " page_size=" SIZE_FORMAT "%s"
1613 " alignment=" SIZE_FORMAT "%s"
1614 " size=" SIZE_FORMAT "%s",
1615 str,
1616 trace_page_size_params(requested_size),
1617 p2i(base),
1618 trace_page_size_params(page_size),
1619 trace_page_size_params(alignment),
1620 trace_page_size_params(size));
1621 }
1622
1623
1624 // This is the working definition of a server class machine:
1625 // >= 2 physical CPU's and >=2GB of memory, with some fuzz
1626 // because the graphics memory (?) sometimes masks physical memory.
1627 // If you want to change the definition of a server class machine
1628 // on some OS or platform, e.g., >=4GB on Windows platforms,
1629 // then you'll have to parameterize this method based on that state,
1630 // as was done for logical processors here, or replicate and
1631 // specialize this method for each platform. (Or fix os to have
1632 // some inheritance structure and use subclassing. Sigh.)
1633 // If you want some platform to always or never behave as a server
1634 // class machine, change the setting of AlwaysActAsServerClassMachine
1635 // and NeverActAsServerClassMachine in globals*.hpp.
1636 bool os::is_server_class_machine() {
1637 // First check for the early returns
1638 if (NeverActAsServerClassMachine) {
1639 return false;
1640 }
1641 if (AlwaysActAsServerClassMachine) {
1642 return true;
1643 }
1644 // Then actually look at the machine
1645 bool result = false;
1646 const unsigned int server_processors = 2;
1647 const julong server_memory = 2UL * G;
1648 // We seem not to get our full complement of memory.
1649 // We allow some part (1/8?) of the memory to be "missing",
1650 // based on the sizes of DIMMs, and maybe graphics cards.
1651 const julong missing_memory = 256UL * M;
1652
1653 /* Is this a server class machine? */
1654 if ((os::active_processor_count() >= (int)server_processors) &&
1655 (os::physical_memory() >= (server_memory - missing_memory))) {
1656 const unsigned int logical_processors =
1657 VM_Version::logical_processors_per_package();
1658 if (logical_processors > 1) {
1659 const unsigned int physical_packages =
1660 os::active_processor_count() / logical_processors;
1661 if (physical_packages >= server_processors) {
1662 result = true;
1663 }
1664 } else {
1665 result = true;
1666 }
1667 }
1668 return result;
1669 }
1670
1671 void os::initialize_initial_active_processor_count() {
1672 assert(_initial_active_processor_count == 0, "Initial active processor count already set.");
1673 _initial_active_processor_count = active_processor_count();
1674 log_debug(os)("Initial active processor count set to %d" , _initial_active_processor_count);
1675 }
1676
1677 void os::SuspendedThreadTask::run() {
1678 internal_do_task();
1679 _done = true;
1680 }
1681
1682 bool os::create_stack_guard_pages(char* addr, size_t bytes) {
1683 return os::pd_create_stack_guard_pages(addr, bytes);
1684 }
1685
1686 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint, int file_desc) {
1687 char* result = NULL;
1688
1689 if (file_desc != -1) {
1690 // Could have called pd_reserve_memory() followed by replace_existing_mapping_with_file_mapping(),
1691 // but AIX may use SHM in which case its more trouble to detach the segment and remap memory to the file.
1692 result = os::map_memory_to_file(addr, bytes, file_desc);
1693 if (result != NULL) {
1694 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC);
1695 }
1696 } else {
1697 result = pd_reserve_memory(bytes, addr, alignment_hint);
1698 if (result != NULL) {
1699 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1700 }
1701 }
1702
1703 return result;
1704 }
1705
1706 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint,
1707 MEMFLAGS flags) {
1708 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1709 if (result != NULL) {
1710 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1711 MemTracker::record_virtual_memory_type((address)result, flags);
1712 }
1713
1714 return result;
1715 }
1716
1717 char* os::attempt_reserve_memory_at(size_t bytes, char* addr, int file_desc) {
1718 char* result = NULL;
1719 if (file_desc != -1) {
1720 result = pd_attempt_reserve_memory_at(bytes, addr, file_desc);
1721 if (result != NULL) {
1722 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC);
1723 }
1724 } else {
1725 result = pd_attempt_reserve_memory_at(bytes, addr);
1726 if (result != NULL) {
1727 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1728 }
1729 }
1730 return result;
1731 }
1732
1733 void os::split_reserved_memory(char *base, size_t size,
1734 size_t split, bool realloc) {
1735 pd_split_reserved_memory(base, size, split, realloc);
1736 }
1737
1738 bool os::commit_memory(char* addr, size_t bytes, bool executable) {
1739 bool res = pd_commit_memory(addr, bytes, executable);
1740 if (res) {
1741 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1742 }
1743 return res;
1744 }
1745
1746 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint,
1747 bool executable) {
1748 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable);
1749 if (res) {
1750 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1751 }
1752 return res;
1753 }
1754
1755 void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable,
1756 const char* mesg) {
1757 pd_commit_memory_or_exit(addr, bytes, executable, mesg);
1758 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1759 }
1760
1761 void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint,
1762 bool executable, const char* mesg) {
1763 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg);
1764 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1765 }
1766
1767 bool os::uncommit_memory(char* addr, size_t bytes) {
1768 bool res;
1769 if (MemTracker::tracking_level() > NMT_minimal) {
1770 Tracker tkr(Tracker::uncommit);
1771 res = pd_uncommit_memory(addr, bytes);
1772 if (res) {
1773 tkr.record((address)addr, bytes);
1774 }
1775 } else {
1776 res = pd_uncommit_memory(addr, bytes);
1777 }
1778 return res;
1779 }
1780
1781 bool os::release_memory(char* addr, size_t bytes) {
1782 bool res;
1783 if (MemTracker::tracking_level() > NMT_minimal) {
1784 Tracker tkr(Tracker::release);
1785 res = pd_release_memory(addr, bytes);
1786 if (res) {
1787 tkr.record((address)addr, bytes);
1788 }
1789 } else {
1790 res = pd_release_memory(addr, bytes);
1791 }
1792 return res;
1793 }
1794
1795 void os::pretouch_memory(void* start, void* end, size_t page_size) {
1796 for (volatile char *p = (char*)start; p < (char*)end; p += page_size) {
1797 *p = 0;
1798 }
1799 }
1800
1801 char* os::map_memory(int fd, const char* file_name, size_t file_offset,
1802 char *addr, size_t bytes, bool read_only,
1803 bool allow_exec) {
1804 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec);
1805 if (result != NULL) {
1806 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC);
1807 }
1808 return result;
1809 }
1810
1811 char* os::remap_memory(int fd, const char* file_name, size_t file_offset,
1812 char *addr, size_t bytes, bool read_only,
1813 bool allow_exec) {
1814 return pd_remap_memory(fd, file_name, file_offset, addr, bytes,
1815 read_only, allow_exec);
1816 }
1817
1818 bool os::unmap_memory(char *addr, size_t bytes) {
1819 bool result;
1820 if (MemTracker::tracking_level() > NMT_minimal) {
1821 Tracker tkr(Tracker::release);
1822 result = pd_unmap_memory(addr, bytes);
1823 if (result) {
1824 tkr.record((address)addr, bytes);
1825 }
1826 } else {
1827 result = pd_unmap_memory(addr, bytes);
1828 }
1829 return result;
1830 }
1831
1832 void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) {
1833 pd_free_memory(addr, bytes, alignment_hint);
1834 }
1835
1836 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
1837 pd_realign_memory(addr, bytes, alignment_hint);
1838 }
1839
1840 #ifndef _WINDOWS
1841 /* try to switch state from state "from" to state "to"
1842 * returns the state set after the method is complete
1843 */
1844 os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from,
1845 os::SuspendResume::State to)
1846 {
1847 os::SuspendResume::State result = Atomic::cmpxchg(to, &_state, from);
1848 if (result == from) {
1849 // success
1850 return to;
1851 }
1852 return result;
1853 }
1854 #endif