1 /*
2 * Copyright (c) 1997, 2014, 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 "classfile/classLoader.hpp"
27 #include "classfile/javaClasses.hpp"
28 #include "classfile/systemDictionary.hpp"
29 #include "classfile/vmSymbols.hpp"
30 #include "code/icBuffer.hpp"
31 #include "code/vtableStubs.hpp"
32 #include "gc_implementation/shared/vmGCOperations.hpp"
33 #include "interpreter/interpreter.hpp"
34 #include "memory/allocation.inline.hpp"
35 #include "oops/oop.inline.hpp"
36 #include "prims/jvm.h"
37 #include "prims/jvm_misc.hpp"
38 #include "prims/privilegedStack.hpp"
39 #include "runtime/arguments.hpp"
40 #include "runtime/atomic.inline.hpp"
41 #include "runtime/frame.inline.hpp"
42 #include "runtime/interfaceSupport.hpp"
43 #include "runtime/java.hpp"
44 #include "runtime/javaCalls.hpp"
45 #include "runtime/mutexLocker.hpp"
46 #include "runtime/os.hpp"
47 #include "runtime/stubRoutines.hpp"
48 #include "runtime/thread.inline.hpp"
49 #include "services/attachListener.hpp"
50 #include "services/memTracker.hpp"
51 #include "services/threadService.hpp"
52 #include "utilities/defaultStream.hpp"
53 #include "utilities/events.hpp"
54 #ifdef TARGET_OS_FAMILY_linux
55 # include "os_linux.inline.hpp"
56 #endif
57 #ifdef TARGET_OS_FAMILY_solaris
58 # include "os_solaris.inline.hpp"
59 #endif
60 #ifdef TARGET_OS_FAMILY_windows
61 # include "os_windows.inline.hpp"
62 #endif
63 #ifdef TARGET_OS_FAMILY_bsd
64 # include "os_bsd.inline.hpp"
65 #endif
66
67 # include <signal.h>
68
69 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
70
71 OSThread* os::_starting_thread = NULL;
72 address os::_polling_page = NULL;
73 volatile int32_t* os::_mem_serialize_page = NULL;
74 uintptr_t os::_serialize_page_mask = 0;
75 long os::_rand_seed = 1;
76 int os::_processor_count = 0;
77 size_t os::_page_sizes[os::page_sizes_max];
78
79 #ifndef PRODUCT
80 julong os::num_mallocs = 0; // # of calls to malloc/realloc
81 julong os::alloc_bytes = 0; // # of bytes allocated
82 julong os::num_frees = 0; // # of calls to free
83 julong os::free_bytes = 0; // # of bytes freed
84 #endif
85
86 static juint cur_malloc_words = 0; // current size for MallocMaxTestWords
87
88 void os_init_globals() {
89 // Called from init_globals().
90 // See Threads::create_vm() in thread.cpp, and init.cpp.
91 os::init_globals();
92 }
93
94 // Fill in buffer with current local time as an ISO-8601 string.
95 // E.g., yyyy-mm-ddThh:mm:ss-zzzz.
96 // Returns buffer, or NULL if it failed.
97 // This would mostly be a call to
98 // strftime(...., "%Y-%m-%d" "T" "%H:%M:%S" "%z", ....)
99 // except that on Windows the %z behaves badly, so we do it ourselves.
100 // Also, people wanted milliseconds on there,
101 // and strftime doesn't do milliseconds.
102 char* os::iso8601_time(char* buffer, size_t buffer_length) {
103 // Output will be of the form "YYYY-MM-DDThh:mm:ss.mmm+zzzz\0"
104 // 1 2
105 // 12345678901234567890123456789
106 static const char* iso8601_format =
107 "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d";
108 static const size_t needed_buffer = 29;
109
110 // Sanity check the arguments
111 if (buffer == NULL) {
112 assert(false, "NULL buffer");
113 return NULL;
114 }
115 if (buffer_length < needed_buffer) {
116 assert(false, "buffer_length too small");
117 return NULL;
118 }
119 // Get the current time
120 jlong milliseconds_since_19700101 = javaTimeMillis();
121 const int milliseconds_per_microsecond = 1000;
122 const time_t seconds_since_19700101 =
123 milliseconds_since_19700101 / milliseconds_per_microsecond;
124 const int milliseconds_after_second =
125 milliseconds_since_19700101 % milliseconds_per_microsecond;
126 // Convert the time value to a tm and timezone variable
127 struct tm time_struct;
128 if (localtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
129 assert(false, "Failed localtime_pd");
130 return NULL;
131 }
132 #if defined(_ALLBSD_SOURCE)
133 const time_t zone = (time_t) time_struct.tm_gmtoff;
134 #else
135 const time_t zone = timezone;
136 #endif
137
138 // If daylight savings time is in effect,
139 // we are 1 hour East of our time zone
140 const time_t seconds_per_minute = 60;
141 const time_t minutes_per_hour = 60;
142 const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour;
143 time_t UTC_to_local = zone;
144 if (time_struct.tm_isdst > 0) {
145 UTC_to_local = UTC_to_local - seconds_per_hour;
146 }
147 // Compute the time zone offset.
148 // localtime_pd() sets timezone to the difference (in seconds)
149 // between UTC and and local time.
150 // ISO 8601 says we need the difference between local time and UTC,
151 // we change the sign of the localtime_pd() result.
152 const time_t local_to_UTC = -(UTC_to_local);
153 // Then we have to figure out if if we are ahead (+) or behind (-) UTC.
154 char sign_local_to_UTC = '+';
155 time_t abs_local_to_UTC = local_to_UTC;
156 if (local_to_UTC < 0) {
157 sign_local_to_UTC = '-';
158 abs_local_to_UTC = -(abs_local_to_UTC);
159 }
160 // Convert time zone offset seconds to hours and minutes.
161 const time_t zone_hours = (abs_local_to_UTC / seconds_per_hour);
162 const time_t zone_min =
163 ((abs_local_to_UTC % seconds_per_hour) / seconds_per_minute);
164
165 // Print an ISO 8601 date and time stamp into the buffer
166 const int year = 1900 + time_struct.tm_year;
167 const int month = 1 + time_struct.tm_mon;
168 const int printed = jio_snprintf(buffer, buffer_length, iso8601_format,
169 year,
170 month,
171 time_struct.tm_mday,
172 time_struct.tm_hour,
173 time_struct.tm_min,
174 time_struct.tm_sec,
175 milliseconds_after_second,
176 sign_local_to_UTC,
177 zone_hours,
178 zone_min);
179 if (printed == 0) {
180 assert(false, "Failed jio_printf");
181 return NULL;
182 }
183 return buffer;
184 }
185
186 OSReturn os::set_priority(Thread* thread, ThreadPriority p) {
187 #ifdef ASSERT
188 if (!(!thread->is_Java_thread() ||
189 Thread::current() == thread ||
190 Threads_lock->owned_by_self()
191 || thread->is_Compiler_thread()
192 )) {
193 assert(false, "possibility of dangling Thread pointer");
194 }
195 #endif
196
197 if (p >= MinPriority && p <= MaxPriority) {
198 int priority = java_to_os_priority[p];
199 return set_native_priority(thread, priority);
200 } else {
201 assert(false, "Should not happen");
202 return OS_ERR;
203 }
204 }
205
206 // The mapping from OS priority back to Java priority may be inexact because
207 // Java priorities can map M:1 with native priorities. If you want the definite
208 // Java priority then use JavaThread::java_priority()
209 OSReturn os::get_priority(const Thread* const thread, ThreadPriority& priority) {
210 int p;
211 int os_prio;
212 OSReturn ret = get_native_priority(thread, &os_prio);
213 if (ret != OS_OK) return ret;
214
215 if (java_to_os_priority[MaxPriority] > java_to_os_priority[MinPriority]) {
216 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] > os_prio; p--) ;
217 } else {
218 // niceness values are in reverse order
219 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] < os_prio; p--) ;
220 }
221 priority = (ThreadPriority)p;
222 return OS_OK;
223 }
224
225
226 // --------------------- sun.misc.Signal (optional) ---------------------
227
228
229 // SIGBREAK is sent by the keyboard to query the VM state
230 #ifndef SIGBREAK
231 #define SIGBREAK SIGQUIT
232 #endif
233
234 // sigexitnum_pd is a platform-specific special signal used for terminating the Signal thread.
235
236
237 static void signal_thread_entry(JavaThread* thread, TRAPS) {
238 os::set_priority(thread, NearMaxPriority);
239 while (true) {
240 int sig;
241 {
242 // FIXME : Currently we have not decided what should be the status
243 // for this java thread blocked here. Once we decide about
244 // that we should fix this.
245 sig = os::signal_wait();
246 }
247 if (sig == os::sigexitnum_pd()) {
248 // Terminate the signal thread
249 return;
250 }
251
252 switch (sig) {
253 case SIGBREAK: {
254 // Check if the signal is a trigger to start the Attach Listener - in that
255 // case don't print stack traces.
256 if (!DisableAttachMechanism && AttachListener::is_init_trigger()) {
257 continue;
258 }
259 // Print stack traces
260 // Any SIGBREAK operations added here should make sure to flush
261 // the output stream (e.g. tty->flush()) after output. See 4803766.
262 // Each module also prints an extra carriage return after its output.
263 VM_PrintThreads op;
264 VMThread::execute(&op);
265 VM_PrintJNI jni_op;
266 VMThread::execute(&jni_op);
267 VM_FindDeadlocks op1(tty);
268 VMThread::execute(&op1);
269 Universe::print_heap_at_SIGBREAK();
270 if (PrintClassHistogram) {
271 VM_GC_HeapInspection op1(gclog_or_tty, true /* force full GC before heap inspection */);
272 VMThread::execute(&op1);
273 }
274 if (JvmtiExport::should_post_data_dump()) {
275 JvmtiExport::post_data_dump();
276 }
277 break;
278 }
279 default: {
280 // Dispatch the signal to java
281 HandleMark hm(THREAD);
282 Klass* k = SystemDictionary::resolve_or_null(vmSymbols::sun_misc_Signal(), THREAD);
283 KlassHandle klass (THREAD, k);
284 if (klass.not_null()) {
285 JavaValue result(T_VOID);
286 JavaCallArguments args;
287 args.push_int(sig);
288 JavaCalls::call_static(
289 &result,
290 klass,
291 vmSymbols::dispatch_name(),
292 vmSymbols::int_void_signature(),
293 &args,
294 THREAD
295 );
296 }
297 if (HAS_PENDING_EXCEPTION) {
298 // tty is initialized early so we don't expect it to be null, but
299 // if it is we can't risk doing an initialization that might
300 // trigger additional out-of-memory conditions
301 if (tty != NULL) {
302 char klass_name[256];
303 char tmp_sig_name[16];
304 const char* sig_name = "UNKNOWN";
305 InstanceKlass::cast(PENDING_EXCEPTION->klass())->
306 name()->as_klass_external_name(klass_name, 256);
307 if (os::exception_name(sig, tmp_sig_name, 16) != NULL)
308 sig_name = tmp_sig_name;
309 warning("Exception %s occurred dispatching signal %s to handler"
310 "- the VM may need to be forcibly terminated",
311 klass_name, sig_name );
312 }
313 CLEAR_PENDING_EXCEPTION;
314 }
315 }
316 }
317 }
318 }
319
320 void os::init_before_ergo() {
321 // We need to initialize large page support here because ergonomics takes some
322 // decisions depending on large page support and the calculated large page size.
323 large_page_init();
324 }
325
326 void os::signal_init() {
327 if (!ReduceSignalUsage) {
328 // Setup JavaThread for processing signals
329 EXCEPTION_MARK;
330 Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(), true, CHECK);
331 instanceKlassHandle klass (THREAD, k);
332 instanceHandle thread_oop = klass->allocate_instance_handle(CHECK);
333
334 const char thread_name[] = "Signal Dispatcher";
335 Handle string = java_lang_String::create_from_str(thread_name, CHECK);
336
337 // Initialize thread_oop to put it into the system threadGroup
338 Handle thread_group (THREAD, Universe::system_thread_group());
339 JavaValue result(T_VOID);
340 JavaCalls::call_special(&result, thread_oop,
341 klass,
342 vmSymbols::object_initializer_name(),
343 vmSymbols::threadgroup_string_void_signature(),
344 thread_group,
345 string,
346 CHECK);
347
348 KlassHandle group(THREAD, SystemDictionary::ThreadGroup_klass());
349 JavaCalls::call_special(&result,
350 thread_group,
351 group,
352 vmSymbols::add_method_name(),
353 vmSymbols::thread_void_signature(),
354 thread_oop, // ARG 1
355 CHECK);
356
357 os::signal_init_pd();
358
359 { MutexLocker mu(Threads_lock);
360 JavaThread* signal_thread = new JavaThread(&signal_thread_entry);
361
362 // At this point it may be possible that no osthread was created for the
363 // JavaThread due to lack of memory. We would have to throw an exception
364 // in that case. However, since this must work and we do not allow
365 // exceptions anyway, check and abort if this fails.
366 if (signal_thread == NULL || signal_thread->osthread() == NULL) {
367 vm_exit_during_initialization("java.lang.OutOfMemoryError",
368 os::native_thread_creation_failed_msg());
369 }
370
371 java_lang_Thread::set_thread(thread_oop(), signal_thread);
372 java_lang_Thread::set_priority(thread_oop(), NearMaxPriority);
373 java_lang_Thread::set_daemon(thread_oop());
374
375 signal_thread->set_threadObj(thread_oop());
376 Threads::add(signal_thread);
377 Thread::start(signal_thread);
378 }
379 // Handle ^BREAK
380 os::signal(SIGBREAK, os::user_handler());
381 }
382 }
383
384
385 void os::terminate_signal_thread() {
386 if (!ReduceSignalUsage)
387 signal_notify(sigexitnum_pd());
388 }
389
390
391 // --------------------- loading libraries ---------------------
392
393 typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *);
394 extern struct JavaVM_ main_vm;
395
396 static void* _native_java_library = NULL;
397
398 void* os::native_java_library() {
399 if (_native_java_library == NULL) {
400 char buffer[JVM_MAXPATHLEN];
401 char ebuf[1024];
402
403 // Try to load verify dll first. In 1.3 java dll depends on it and is not
404 // always able to find it when the loading executable is outside the JDK.
405 // In order to keep working with 1.2 we ignore any loading errors.
406 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
407 "verify")) {
408 dll_load(buffer, ebuf, sizeof(ebuf));
409 }
410
411 // Load java dll
412 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
413 "java")) {
414 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf));
415 }
416 if (_native_java_library == NULL) {
417 vm_exit_during_initialization("Unable to load native library", ebuf);
418 }
419
420 #if defined(__OpenBSD__)
421 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so
422 // ignore errors
423 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
424 "net")) {
425 dll_load(buffer, ebuf, sizeof(ebuf));
426 }
427 #endif
428 }
429 static jboolean onLoaded = JNI_FALSE;
430 if (onLoaded) {
431 // We may have to wait to fire OnLoad until TLS is initialized.
432 if (ThreadLocalStorage::is_initialized()) {
433 // The JNI_OnLoad handling is normally done by method load in
434 // java.lang.ClassLoader$NativeLibrary, but the VM loads the base library
435 // explicitly so we have to check for JNI_OnLoad as well
436 const char *onLoadSymbols[] = JNI_ONLOAD_SYMBOLS;
437 JNI_OnLoad_t JNI_OnLoad = CAST_TO_FN_PTR(
438 JNI_OnLoad_t, dll_lookup(_native_java_library, onLoadSymbols[0]));
439 if (JNI_OnLoad != NULL) {
440 JavaThread* thread = JavaThread::current();
441 ThreadToNativeFromVM ttn(thread);
442 HandleMark hm(thread);
443 jint ver = (*JNI_OnLoad)(&main_vm, NULL);
444 onLoaded = JNI_TRUE;
445 if (!Threads::is_supported_jni_version_including_1_1(ver)) {
446 vm_exit_during_initialization("Unsupported JNI version");
447 }
448 }
449 }
450 }
451 return _native_java_library;
452 }
453
454 /*
455 * Support for finding Agent_On(Un)Load/Attach<_lib_name> if it exists.
456 * If check_lib == true then we are looking for an
457 * Agent_OnLoad_lib_name or Agent_OnAttach_lib_name function to determine if
458 * this library is statically linked into the image.
459 * If check_lib == false then we will look for the appropriate symbol in the
460 * executable if agent_lib->is_static_lib() == true or in the shared library
461 * referenced by 'handle'.
462 */
463 void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib,
464 const char *syms[], size_t syms_len) {
465 assert(agent_lib != NULL, "sanity check");
466 const char *lib_name;
467 void *handle = agent_lib->os_lib();
468 void *entryName = NULL;
469 char *agent_function_name;
470 size_t i;
471
472 // If checking then use the agent name otherwise test is_static_lib() to
473 // see how to process this lookup
474 lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL);
475 for (i = 0; i < syms_len; i++) {
476 agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path());
477 if (agent_function_name == NULL) {
478 break;
479 }
480 entryName = dll_lookup(handle, agent_function_name);
481 FREE_C_HEAP_ARRAY(char, agent_function_name, mtThread);
482 if (entryName != NULL) {
483 break;
484 }
485 }
486 return entryName;
487 }
488
489 // See if the passed in agent is statically linked into the VM image.
490 bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
491 size_t syms_len) {
492 void *ret;
493 void *proc_handle;
494 void *save_handle;
495
496 assert(agent_lib != NULL, "sanity check");
497 if (agent_lib->name() == NULL) {
498 return false;
499 }
500 proc_handle = get_default_process_handle();
501 // Check for Agent_OnLoad/Attach_lib_name function
502 save_handle = agent_lib->os_lib();
503 // We want to look in this process' symbol table.
504 agent_lib->set_os_lib(proc_handle);
505 ret = find_agent_function(agent_lib, true, syms, syms_len);
506 if (ret != NULL) {
507 // Found an entry point like Agent_OnLoad_lib_name so we have a static agent
508 agent_lib->set_valid();
509 agent_lib->set_static_lib(true);
510 return true;
511 }
512 agent_lib->set_os_lib(save_handle);
513 return false;
514 }
515
516 // --------------------- heap allocation utilities ---------------------
517
518 char *os::strdup(const char *str, MEMFLAGS flags) {
519 size_t size = strlen(str);
520 char *dup_str = (char *)malloc(size + 1, flags);
521 if (dup_str == NULL) return NULL;
522 strcpy(dup_str, str);
523 return dup_str;
524 }
525
526
527
528 #ifdef ASSERT
529 #define space_before (MallocCushion + sizeof(double))
530 #define space_after MallocCushion
531 #define size_addr_from_base(p) (size_t*)(p + space_before - sizeof(size_t))
532 #define size_addr_from_obj(p) ((size_t*)p - 1)
533 // MallocCushion: size of extra cushion allocated around objects with +UseMallocOnly
534 // NB: cannot be debug variable, because these aren't set from the command line until
535 // *after* the first few allocs already happened
536 #define MallocCushion 16
537 #else
538 #define space_before 0
539 #define space_after 0
540 #define size_addr_from_base(p) should not use w/o ASSERT
541 #define size_addr_from_obj(p) should not use w/o ASSERT
542 #define MallocCushion 0
543 #endif
544 #define paranoid 0 /* only set to 1 if you suspect checking code has bug */
545
546 #ifdef ASSERT
547 inline size_t get_size(void* obj) {
548 size_t size = *size_addr_from_obj(obj);
549 if (size < 0) {
550 fatal(err_msg("free: size field of object #" PTR_FORMAT " was overwritten ("
551 SIZE_FORMAT ")", obj, size));
552 }
553 return size;
554 }
555
556 u_char* find_cushion_backwards(u_char* start) {
557 u_char* p = start;
558 while (p[ 0] != badResourceValue || p[-1] != badResourceValue ||
559 p[-2] != badResourceValue || p[-3] != badResourceValue) p--;
560 // ok, we have four consecutive marker bytes; find start
561 u_char* q = p - 4;
562 while (*q == badResourceValue) q--;
563 return q + 1;
564 }
565
566 u_char* find_cushion_forwards(u_char* start) {
567 u_char* p = start;
568 while (p[0] != badResourceValue || p[1] != badResourceValue ||
569 p[2] != badResourceValue || p[3] != badResourceValue) p++;
570 // ok, we have four consecutive marker bytes; find end of cushion
571 u_char* q = p + 4;
572 while (*q == badResourceValue) q++;
573 return q - MallocCushion;
574 }
575
576 void print_neighbor_blocks(void* ptr) {
577 // find block allocated before ptr (not entirely crash-proof)
578 if (MallocCushion < 4) {
579 tty->print_cr("### cannot find previous block (MallocCushion < 4)");
580 return;
581 }
582 u_char* start_of_this_block = (u_char*)ptr - space_before;
583 u_char* end_of_prev_block_data = start_of_this_block - space_after -1;
584 // look for cushion in front of prev. block
585 u_char* start_of_prev_block = find_cushion_backwards(end_of_prev_block_data);
586 ptrdiff_t size = *size_addr_from_base(start_of_prev_block);
587 u_char* obj = start_of_prev_block + space_before;
588 if (size <= 0 ) {
589 // start is bad; may have been confused by OS data in between objects
590 // search one more backwards
591 start_of_prev_block = find_cushion_backwards(start_of_prev_block);
592 size = *size_addr_from_base(start_of_prev_block);
593 obj = start_of_prev_block + space_before;
594 }
595
596 if (start_of_prev_block + space_before + size + space_after == start_of_this_block) {
597 tty->print_cr("### previous object: " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", obj, size);
598 } else {
599 tty->print_cr("### previous object (not sure if correct): " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", obj, size);
600 }
601
602 // now find successor block
603 u_char* start_of_next_block = (u_char*)ptr + *size_addr_from_obj(ptr) + space_after;
604 start_of_next_block = find_cushion_forwards(start_of_next_block);
605 u_char* next_obj = start_of_next_block + space_before;
606 ptrdiff_t next_size = *size_addr_from_base(start_of_next_block);
607 if (start_of_next_block[0] == badResourceValue &&
608 start_of_next_block[1] == badResourceValue &&
609 start_of_next_block[2] == badResourceValue &&
610 start_of_next_block[3] == badResourceValue) {
611 tty->print_cr("### next object: " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", next_obj, next_size);
612 } else {
613 tty->print_cr("### next object (not sure if correct): " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", next_obj, next_size);
614 }
615 }
616
617
618 void report_heap_error(void* memblock, void* bad, const char* where) {
619 tty->print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees);
620 tty->print_cr("## memory stomp: byte at " PTR_FORMAT " %s object " PTR_FORMAT, bad, where, memblock);
621 print_neighbor_blocks(memblock);
622 fatal("memory stomping error");
623 }
624
625 void verify_block(void* memblock) {
626 size_t size = get_size(memblock);
627 if (MallocCushion) {
628 u_char* ptr = (u_char*)memblock - space_before;
629 for (int i = 0; i < MallocCushion; i++) {
630 if (ptr[i] != badResourceValue) {
631 report_heap_error(memblock, ptr+i, "in front of");
632 }
633 }
634 u_char* end = (u_char*)memblock + size + space_after;
635 for (int j = -MallocCushion; j < 0; j++) {
636 if (end[j] != badResourceValue) {
637 report_heap_error(memblock, end+j, "after");
638 }
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 u_char* testMalloc(size_t alloc_size) {
649 assert(MallocMaxTestWords > 0, "sanity check");
650
651 if ((cur_malloc_words + (alloc_size / BytesPerWord)) > MallocMaxTestWords) {
652 return NULL;
653 }
654
655 u_char* ptr = (u_char*)::malloc(alloc_size);
656
657 if (ptr != NULL) {
658 Atomic::add(((jint) (alloc_size / BytesPerWord)),
659 (volatile jint *) &cur_malloc_words);
660 }
661 return ptr;
662 }
663
664 void* os::malloc(size_t size, MEMFLAGS memflags, address caller) {
665 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
666 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
667
668 #ifdef ASSERT
669 // checking for the WatcherThread and crash_protection first
670 // since os::malloc can be called when the libjvm.{dll,so} is
671 // first loaded and we don't have a thread yet.
672 // try to find the thread after we see that the watcher thread
673 // exists and has crash protection.
674 WatcherThread *wt = WatcherThread::watcher_thread();
675 if (wt != NULL && wt->has_crash_protection()) {
676 Thread* thread = ThreadLocalStorage::get_thread_slow();
677 if (thread == wt) {
678 assert(!wt->has_crash_protection(),
679 "Can't malloc with crash protection from WatcherThread");
680 }
681 }
682 #endif
683
684 if (size == 0) {
685 // return a valid pointer if size is zero
686 // if NULL is returned the calling functions assume out of memory.
687 size = 1;
688 }
689
690 const size_t alloc_size = size + space_before + space_after;
691
692 if (size > alloc_size) { // Check for rollover.
693 return NULL;
694 }
695
696 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
697
698 u_char* ptr;
699
700 if (MallocMaxTestWords > 0) {
701 ptr = testMalloc(alloc_size);
702 } else {
703 ptr = (u_char*)::malloc(alloc_size);
704 }
705
706 #ifdef ASSERT
707 if (ptr == NULL) return NULL;
708 if (MallocCushion) {
709 for (u_char* p = ptr; p < ptr + MallocCushion; p++) *p = (u_char)badResourceValue;
710 u_char* end = ptr + space_before + size;
711 for (u_char* pq = ptr+MallocCushion; pq < end; pq++) *pq = (u_char)uninitBlockPad;
712 for (u_char* q = end; q < end + MallocCushion; q++) *q = (u_char)badResourceValue;
713 }
714 // put size just before data
715 *size_addr_from_base(ptr) = size;
716 #endif
717 u_char* memblock = ptr + space_before;
718 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
719 tty->print_cr("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, memblock);
720 breakpoint();
721 }
722 debug_only(if (paranoid) verify_block(memblock));
723 if (PrintMalloc && tty != NULL) tty->print_cr("os::malloc " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, memblock);
724
725 // we do not track MallocCushion memory
726 MemTracker::record_malloc((address)memblock, size, memflags, caller == 0 ? CALLER_PC : caller);
727
728 return memblock;
729 }
730
731
732 void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, address caller) {
733 #ifndef ASSERT
734 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
735 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
736 MemTracker::Tracker tkr = MemTracker::get_realloc_tracker();
737 void* ptr = ::realloc(memblock, size);
738 if (ptr != NULL) {
739 tkr.record((address)memblock, (address)ptr, size, memflags,
740 caller == 0 ? CALLER_PC : caller);
741 } else {
742 tkr.discard();
743 }
744 return ptr;
745 #else
746 if (memblock == NULL) {
747 return malloc(size, memflags, (caller == 0 ? CALLER_PC : caller));
748 }
749 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
750 tty->print_cr("os::realloc caught " PTR_FORMAT, memblock);
751 breakpoint();
752 }
753 verify_block(memblock);
754 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
755 if (size == 0) return NULL;
756 // always move the block
757 void* ptr = malloc(size, memflags, caller == 0 ? CALLER_PC : caller);
758 if (PrintMalloc) tty->print_cr("os::remalloc " SIZE_FORMAT " bytes, " PTR_FORMAT " --> " PTR_FORMAT, size, memblock, ptr);
759 // Copy to new memory if malloc didn't fail
760 if ( ptr != NULL ) {
761 memcpy(ptr, memblock, MIN2(size, get_size(memblock)));
762 if (paranoid) verify_block(ptr);
763 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) {
764 tty->print_cr("os::realloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr);
765 breakpoint();
766 }
767 free(memblock);
768 }
769 return ptr;
770 #endif
771 }
772
773
774 void os::free(void *memblock, MEMFLAGS memflags) {
775 NOT_PRODUCT(inc_stat_counter(&num_frees, 1));
776 #ifdef ASSERT
777 if (memblock == NULL) return;
778 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
779 if (tty != NULL) tty->print_cr("os::free caught " PTR_FORMAT, memblock);
780 breakpoint();
781 }
782 verify_block(memblock);
783 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
784 // Added by detlefs.
785 if (MallocCushion) {
786 u_char* ptr = (u_char*)memblock - space_before;
787 for (u_char* p = ptr; p < ptr + MallocCushion; p++) {
788 guarantee(*p == badResourceValue,
789 "Thing freed should be malloc result.");
790 *p = (u_char)freeBlockPad;
791 }
792 size_t size = get_size(memblock);
793 inc_stat_counter(&free_bytes, size);
794 u_char* end = ptr + space_before + size;
795 for (u_char* q = end; q < end + MallocCushion; q++) {
796 guarantee(*q == badResourceValue,
797 "Thing freed should be malloc result.");
798 *q = (u_char)freeBlockPad;
799 }
800 if (PrintMalloc && tty != NULL)
801 fprintf(stderr, "os::free " SIZE_FORMAT " bytes --> " PTR_FORMAT "\n", size, (uintptr_t)memblock);
802 } else if (PrintMalloc && tty != NULL) {
803 // tty->print_cr("os::free %p", memblock);
804 fprintf(stderr, "os::free " PTR_FORMAT "\n", (uintptr_t)memblock);
805 }
806 #endif
807 MemTracker::record_free((address)memblock, memflags);
808
809 ::free((char*)memblock - space_before);
810 }
811
812 void os::init_random(long initval) {
813 _rand_seed = initval;
814 }
815
816
817 long os::random() {
818 /* standard, well-known linear congruential random generator with
819 * next_rand = (16807*seed) mod (2**31-1)
820 * see
821 * (1) "Random Number Generators: Good Ones Are Hard to Find",
822 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988),
823 * (2) "Two Fast Implementations of the 'Minimal Standard' Random
824 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88.
825 */
826 const long a = 16807;
827 const unsigned long m = 2147483647;
828 const long q = m / a; assert(q == 127773, "weird math");
829 const long r = m % a; assert(r == 2836, "weird math");
830
831 // compute az=2^31p+q
832 unsigned long lo = a * (long)(_rand_seed & 0xFFFF);
833 unsigned long hi = a * (long)((unsigned long)_rand_seed >> 16);
834 lo += (hi & 0x7FFF) << 16;
835
836 // if q overflowed, ignore the overflow and increment q
837 if (lo > m) {
838 lo &= m;
839 ++lo;
840 }
841 lo += hi >> 15;
842
843 // if (p+q) overflowed, ignore the overflow and increment (p+q)
844 if (lo > m) {
845 lo &= m;
846 ++lo;
847 }
848 return (_rand_seed = lo);
849 }
850
851 // The INITIALIZED state is distinguished from the SUSPENDED state because the
852 // conditions in which a thread is first started are different from those in which
853 // a suspension is resumed. These differences make it hard for us to apply the
854 // tougher checks when starting threads that we want to do when resuming them.
855 // However, when start_thread is called as a result of Thread.start, on a Java
856 // thread, the operation is synchronized on the Java Thread object. So there
857 // cannot be a race to start the thread and hence for the thread to exit while
858 // we are working on it. Non-Java threads that start Java threads either have
859 // to do so in a context in which races are impossible, or should do appropriate
860 // locking.
861
862 void os::start_thread(Thread* thread) {
863 // guard suspend/resume
864 MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag);
865 OSThread* osthread = thread->osthread();
866 osthread->set_state(RUNNABLE);
867 pd_start_thread(thread);
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 ": ", 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 ": ", 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 char* buffer, int len) {
910 if (env_list) {
911 st->print_cr("Environment Variables:");
912
913 for (int i = 0; env_list[i] != NULL; i++) {
914 if (getenv(env_list[i], buffer, len)) {
915 st->print("%s", env_list[i]);
916 st->print("=");
917 st->print_cr("%s", buffer);
918 }
919 }
920 }
921 }
922
923 void os::print_cpu_info(outputStream* st) {
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());
929 st->print(" %s", VM_Version::cpu_features());
930 st->cr();
931 pd_print_cpu_info(st);
932 }
933
934 void os::print_date_and_time(outputStream *st) {
935 const int secs_per_day = 86400;
936 const int secs_per_hour = 3600;
937 const int secs_per_min = 60;
938
939 time_t tloc;
940 (void)time(&tloc);
941 st->print("time: %s", ctime(&tloc)); // ctime adds newline.
942
943 double t = os::elapsedTime();
944 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in
945 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int
946 // before printf. We lost some precision, but who cares?
947 int eltime = (int)t; // elapsed time in seconds
948
949 // print elapsed time in a human-readable format:
950 int eldays = eltime / secs_per_day;
951 int day_secs = eldays * secs_per_day;
952 int elhours = (eltime - day_secs) / secs_per_hour;
953 int hour_secs = elhours * secs_per_hour;
954 int elmins = (eltime - day_secs - hour_secs) / secs_per_min;
955 int minute_secs = elmins * secs_per_min;
956 int elsecs = (eltime - day_secs - hour_secs - minute_secs);
957 st->print_cr("elapsed time: %d seconds (%dd %dh %dm %ds)", eltime, eldays, elhours, elmins, elsecs);
958 }
959
960 // moved from debug.cpp (used to be find()) but still called from there
961 // The verbose parameter is only set by the debug code in one case
962 void os::print_location(outputStream* st, intptr_t x, bool verbose) {
963 address addr = (address)x;
964 CodeBlob* b = CodeCache::find_blob_unsafe(addr);
965 if (b != NULL) {
966 if (b->is_buffer_blob()) {
967 // the interpreter is generated into a buffer blob
968 InterpreterCodelet* i = Interpreter::codelet_containing(addr);
969 if (i != NULL) {
970 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an Interpreter codelet", addr, (int)(addr - i->code_begin()));
971 i->print_on(st);
972 return;
973 }
974 if (Interpreter::contains(addr)) {
975 st->print_cr(INTPTR_FORMAT " is pointing into interpreter code"
976 " (not bytecode specific)", addr);
977 return;
978 }
979 //
980 if (AdapterHandlerLibrary::contains(b)) {
981 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an AdapterHandler", addr, (int)(addr - b->code_begin()));
982 AdapterHandlerLibrary::print_handler_on(st, b);
983 }
984 // the stubroutines are generated into a buffer blob
985 StubCodeDesc* d = StubCodeDesc::desc_for(addr);
986 if (d != NULL) {
987 st->print_cr(INTPTR_FORMAT " is at begin+%d in a stub", addr, (int)(addr - d->begin()));
988 d->print_on(st);
989 st->cr();
990 return;
991 }
992 if (StubRoutines::contains(addr)) {
993 st->print_cr(INTPTR_FORMAT " is pointing to an (unnamed) "
994 "stub routine", addr);
995 return;
996 }
997 // the InlineCacheBuffer is using stubs generated into a buffer blob
998 if (InlineCacheBuffer::contains(addr)) {
999 st->print_cr(INTPTR_FORMAT " is pointing into InlineCacheBuffer", addr);
1000 return;
1001 }
1002 VtableStub* v = VtableStubs::stub_containing(addr);
1003 if (v != NULL) {
1004 st->print_cr(INTPTR_FORMAT " is at entry_point+%d in a vtable stub", addr, (int)(addr - v->entry_point()));
1005 v->print_on(st);
1006 st->cr();
1007 return;
1008 }
1009 }
1010 nmethod* nm = b->as_nmethod_or_null();
1011 if (nm != NULL) {
1012 ResourceMark rm;
1013 st->print(INTPTR_FORMAT " is at entry_point+%d in (nmethod*)" INTPTR_FORMAT,
1014 addr, (int)(addr - nm->entry_point()), nm);
1015 if (verbose) {
1016 st->print(" for ");
1017 nm->method()->print_value_on(st);
1018 }
1019 st->cr();
1020 nm->print_nmethod(verbose);
1021 return;
1022 }
1023 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in ", addr, (int)(addr - b->code_begin()));
1024 b->print_on(st);
1025 return;
1026 }
1027
1028 if (Universe::heap()->is_in(addr)) {
1029 HeapWord* p = Universe::heap()->block_start(addr);
1030 bool print = false;
1031 // If we couldn't find it it just may mean that heap wasn't parsable
1032 // See if we were just given an oop directly
1033 if (p != NULL && Universe::heap()->block_is_obj(p)) {
1034 print = true;
1035 } else if (p == NULL && ((oopDesc*)addr)->is_oop()) {
1036 p = (HeapWord*) addr;
1037 print = true;
1038 }
1039 if (print) {
1040 if (p == (HeapWord*) addr) {
1041 st->print_cr(INTPTR_FORMAT " is an oop", addr);
1042 } else {
1043 st->print_cr(INTPTR_FORMAT " is pointing into object: " INTPTR_FORMAT, addr, p);
1044 }
1045 oop(p)->print_on(st);
1046 return;
1047 }
1048 } else {
1049 if (Universe::heap()->is_in_reserved(addr)) {
1050 st->print_cr(INTPTR_FORMAT " is an unallocated location "
1051 "in the heap", addr);
1052 return;
1053 }
1054 }
1055 if (JNIHandles::is_global_handle((jobject) addr)) {
1056 st->print_cr(INTPTR_FORMAT " is a global jni handle", addr);
1057 return;
1058 }
1059 if (JNIHandles::is_weak_global_handle((jobject) addr)) {
1060 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", addr);
1061 return;
1062 }
1063 #ifndef PRODUCT
1064 // we don't keep the block list in product mode
1065 if (JNIHandleBlock::any_contains((jobject) addr)) {
1066 st->print_cr(INTPTR_FORMAT " is a local jni handle", addr);
1067 return;
1068 }
1069 #endif
1070
1071 for(JavaThread *thread = Threads::first(); thread; thread = thread->next()) {
1072 // Check for privilege stack
1073 if (thread->privileged_stack_top() != NULL &&
1074 thread->privileged_stack_top()->contains(addr)) {
1075 st->print_cr(INTPTR_FORMAT " is pointing into the privilege stack "
1076 "for thread: " INTPTR_FORMAT, addr, thread);
1077 if (verbose) thread->print_on(st);
1078 return;
1079 }
1080 // If the addr is a java thread print information about that.
1081 if (addr == (address)thread) {
1082 if (verbose) {
1083 thread->print_on(st);
1084 } else {
1085 st->print_cr(INTPTR_FORMAT " is a thread", addr);
1086 }
1087 return;
1088 }
1089 // If the addr is in the stack region for this thread then report that
1090 // and print thread info
1091 if (thread->stack_base() >= addr &&
1092 addr > (thread->stack_base() - thread->stack_size())) {
1093 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: "
1094 INTPTR_FORMAT, addr, thread);
1095 if (verbose) thread->print_on(st);
1096 return;
1097 }
1098
1099 }
1100
1101 // Check if in metaspace and print types that have vptrs (only method now)
1102 if (Metaspace::contains(addr)) {
1103 if (Method::has_method_vptr((const void*)addr)) {
1104 ((Method*)addr)->print_value_on(st);
1105 st->cr();
1106 } else {
1107 // Use addr->print() from the debugger instead (not here)
1108 st->print_cr(INTPTR_FORMAT " is pointing into metadata", addr);
1109 }
1110 return;
1111 }
1112
1113 // Try an OS specific find
1114 if (os::find(addr, st)) {
1115 return;
1116 }
1117
1118 st->print_cr(INTPTR_FORMAT " is an unknown value", addr);
1119 }
1120
1121 // Looks like all platforms except IA64 can use the same function to check
1122 // if C stack is walkable beyond current frame. The check for fp() is not
1123 // necessary on Sparc, but it's harmless.
1124 bool os::is_first_C_frame(frame* fr) {
1125 #if (defined(IA64) && !defined(AIX)) && !defined(_WIN32)
1126 // On IA64 we have to check if the callers bsp is still valid
1127 // (i.e. within the register stack bounds).
1128 // Notice: this only works for threads created by the VM and only if
1129 // we walk the current stack!!! If we want to be able to walk
1130 // arbitrary other threads, we'll have to somehow store the thread
1131 // object in the frame.
1132 Thread *thread = Thread::current();
1133 if ((address)fr->fp() <=
1134 thread->register_stack_base() HPUX_ONLY(+ 0x0) LINUX_ONLY(+ 0x50)) {
1135 // This check is a little hacky, because on Linux the first C
1136 // frame's ('start_thread') register stack frame starts at
1137 // "register_stack_base + 0x48" while on HPUX, the first C frame's
1138 // ('__pthread_bound_body') register stack frame seems to really
1139 // start at "register_stack_base".
1140 return true;
1141 } else {
1142 return false;
1143 }
1144 #elif defined(IA64) && defined(_WIN32)
1145 return true;
1146 #else
1147 // Load up sp, fp, sender sp and sender fp, check for reasonable values.
1148 // Check usp first, because if that's bad the other accessors may fault
1149 // on some architectures. Ditto ufp second, etc.
1150 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1);
1151 // sp on amd can be 32 bit aligned.
1152 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1);
1153
1154 uintptr_t usp = (uintptr_t)fr->sp();
1155 if ((usp & sp_align_mask) != 0) return true;
1156
1157 uintptr_t ufp = (uintptr_t)fr->fp();
1158 if ((ufp & fp_align_mask) != 0) return true;
1159
1160 uintptr_t old_sp = (uintptr_t)fr->sender_sp();
1161 if ((old_sp & sp_align_mask) != 0) return true;
1162 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true;
1163
1164 uintptr_t old_fp = (uintptr_t)fr->link();
1165 if ((old_fp & fp_align_mask) != 0) return true;
1166 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true;
1167
1168 // stack grows downwards; if old_fp is below current fp or if the stack
1169 // frame is too large, either the stack is corrupted or fp is not saved
1170 // on stack (i.e. on x86, ebp may be used as general register). The stack
1171 // is not walkable beyond current frame.
1172 if (old_fp < ufp) return true;
1173 if (old_fp - ufp > 64 * K) return true;
1174
1175 return false;
1176 #endif
1177 }
1178
1179 #ifdef ASSERT
1180 extern "C" void test_random() {
1181 const double m = 2147483647;
1182 double mean = 0.0, variance = 0.0, t;
1183 long reps = 10000;
1184 unsigned long seed = 1;
1185
1186 tty->print_cr("seed %ld for %ld repeats...", seed, reps);
1187 os::init_random(seed);
1188 long num;
1189 for (int k = 0; k < reps; k++) {
1190 num = os::random();
1191 double u = (double)num / m;
1192 assert(u >= 0.0 && u <= 1.0, "bad random number!");
1193
1194 // calculate mean and variance of the random sequence
1195 mean += u;
1196 variance += (u*u);
1197 }
1198 mean /= reps;
1199 variance /= (reps - 1);
1200
1201 assert(num == 1043618065, "bad seed");
1202 tty->print_cr("mean of the 1st 10000 numbers: %f", mean);
1203 tty->print_cr("variance of the 1st 10000 numbers: %f", variance);
1204 const double eps = 0.0001;
1205 t = fabsd(mean - 0.5018);
1206 assert(t < eps, "bad mean");
1207 t = (variance - 0.3355) < 0.0 ? -(variance - 0.3355) : variance - 0.3355;
1208 assert(t < eps, "bad variance");
1209 }
1210 #endif
1211
1212
1213 // Set up the boot classpath.
1214
1215 char* os::format_boot_path(const char* format_string,
1216 const char* home,
1217 int home_len,
1218 char fileSep,
1219 char pathSep) {
1220 assert((fileSep == '/' && pathSep == ':') ||
1221 (fileSep == '\\' && pathSep == ';'), "unexpected separator chars");
1222
1223 // Scan the format string to determine the length of the actual
1224 // boot classpath, and handle platform dependencies as well.
1225 int formatted_path_len = 0;
1226 const char* p;
1227 for (p = format_string; *p != 0; ++p) {
1228 if (*p == '%') formatted_path_len += home_len - 1;
1229 ++formatted_path_len;
1230 }
1231
1232 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal);
1233 if (formatted_path == NULL) {
1234 return NULL;
1235 }
1236
1237 // Create boot classpath from format, substituting separator chars and
1238 // java home directory.
1239 char* q = formatted_path;
1240 for (p = format_string; *p != 0; ++p) {
1241 switch (*p) {
1242 case '%':
1243 strcpy(q, home);
1244 q += home_len;
1245 break;
1246 case '/':
1247 *q++ = fileSep;
1248 break;
1249 case ':':
1250 *q++ = pathSep;
1251 break;
1252 default:
1253 *q++ = *p;
1254 }
1255 }
1256 *q = '\0';
1257
1258 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched");
1259 return formatted_path;
1260 }
1261
1262
1263 bool os::set_boot_path(char fileSep, char pathSep) {
1264 const char* home = Arguments::get_java_home();
1265 int home_len = (int)strlen(home);
1266
1267 static const char* meta_index_dir_format = "%/lib/";
1268 static const char* meta_index_format = "%/lib/meta-index";
1269 char* meta_index = format_boot_path(meta_index_format, home, home_len, fileSep, pathSep);
1270 if (meta_index == NULL) return false;
1271 char* meta_index_dir = format_boot_path(meta_index_dir_format, home, home_len, fileSep, pathSep);
1272 if (meta_index_dir == NULL) return false;
1273 Arguments::set_meta_index_path(meta_index, meta_index_dir);
1274
1275 // Any modification to the JAR-file list, for the boot classpath must be
1276 // aligned with install/install/make/common/Pack.gmk. Note: boot class
1277 // path class JARs, are stripped for StackMapTable to reduce download size.
1278 static const char classpath_format[] =
1279 "%/lib/resources.jar:"
1280 "%/lib/rt.jar:"
1281 "%/lib/sunrsasign.jar:"
1282 "%/lib/jsse.jar:"
1283 "%/lib/jce.jar:"
1284 "%/lib/charsets.jar:"
1285 "%/lib/jfr.jar:"
1286 "%/classes";
1287 char* sysclasspath = format_boot_path(classpath_format, home, home_len, fileSep, pathSep);
1288 if (sysclasspath == NULL) return false;
1289 Arguments::set_sysclasspath(sysclasspath);
1290
1291 return true;
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, mtInternal);
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,
1354 "thread size changed, fix SerializePageShiftCount constant");
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 if (TraceSafepoint) {
1365 tty->print_cr("Block until the serialize page permission restored");
1366 }
1367 // When VMThread is holding the SerializePageLock during modifying the
1368 // access permission of the memory serialize page, the following call
1369 // will block until the permission of that page is restored to rw.
1370 // Generally, it is unsafe to manipulate locks in signal handlers, but in
1371 // this case, it's OK as the signal is synchronous and we know precisely when
1372 // it can occur.
1373 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page");
1374 Thread::muxRelease(&SerializePageLock);
1375 }
1376
1377 // Serialize all thread state variables
1378 void os::serialize_thread_states() {
1379 // On some platforms such as Solaris & Linux, the time duration of the page
1380 // permission restoration is observed to be much longer than expected due to
1381 // scheduler starvation problem etc. To avoid the long synchronization
1382 // time and expensive page trap spinning, 'SerializePageLock' is used to block
1383 // the mutator thread if such case is encountered. See bug 6546278 for details.
1384 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states");
1385 os::protect_memory((char *)os::get_memory_serialize_page(),
1386 os::vm_page_size(), MEM_PROT_READ);
1387 os::protect_memory((char *)os::get_memory_serialize_page(),
1388 os::vm_page_size(), MEM_PROT_RW);
1389 Thread::muxRelease(&SerializePageLock);
1390 }
1391
1392 // Returns true if the current stack pointer is above the stack shadow
1393 // pages, false otherwise.
1394
1395 bool os::stack_shadow_pages_available(Thread *thread, methodHandle method) {
1396 assert(StackRedPages > 0 && StackYellowPages > 0,"Sanity check");
1397 address sp = current_stack_pointer();
1398 // Check if we have StackShadowPages above the yellow zone. This parameter
1399 // is dependent on the depth of the maximum VM call stack possible from
1400 // the handler for stack overflow. 'instanceof' in the stack overflow
1401 // handler or a println uses at least 8k stack of VM and native code
1402 // respectively.
1403 const int framesize_in_bytes =
1404 Interpreter::size_top_interpreter_activation(method()) * wordSize;
1405 int reserved_area = ((StackShadowPages + StackRedPages + StackYellowPages)
1406 * vm_page_size()) + framesize_in_bytes;
1407 // The very lower end of the stack
1408 address stack_limit = thread->stack_base() - thread->stack_size();
1409 return (sp > (stack_limit + reserved_area));
1410 }
1411
1412 size_t os::page_size_for_region(size_t region_min_size, size_t region_max_size,
1413 uint min_pages)
1414 {
1415 assert(min_pages > 0, "sanity");
1416 if (UseLargePages) {
1417 const size_t max_page_size = region_max_size / min_pages;
1418
1419 for (unsigned int i = 0; _page_sizes[i] != 0; ++i) {
1420 const size_t sz = _page_sizes[i];
1421 const size_t mask = sz - 1;
1422 if ((region_min_size & mask) == 0 && (region_max_size & mask) == 0) {
1423 // The largest page size with no fragmentation.
1424 return sz;
1425 }
1426
1427 if (sz <= max_page_size) {
1428 // The largest page size that satisfies the min_pages requirement.
1429 return sz;
1430 }
1431 }
1432 }
1433
1434 return vm_page_size();
1435 }
1436
1437 #ifndef PRODUCT
1438 void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count)
1439 {
1440 if (TracePageSizes) {
1441 tty->print("%s: ", str);
1442 for (int i = 0; i < count; ++i) {
1443 tty->print(" " SIZE_FORMAT, page_sizes[i]);
1444 }
1445 tty->cr();
1446 }
1447 }
1448
1449 void os::trace_page_sizes(const char* str, const size_t region_min_size,
1450 const size_t region_max_size, const size_t page_size,
1451 const char* base, const size_t size)
1452 {
1453 if (TracePageSizes) {
1454 tty->print_cr("%s: min=" SIZE_FORMAT " max=" SIZE_FORMAT
1455 " pg_sz=" SIZE_FORMAT " base=" PTR_FORMAT
1456 " size=" SIZE_FORMAT,
1457 str, region_min_size, region_max_size,
1458 page_size, base, size);
1459 }
1460 }
1461 #endif // #ifndef PRODUCT
1462
1463 // This is the working definition of a server class machine:
1464 // >= 2 physical CPU's and >=2GB of memory, with some fuzz
1465 // because the graphics memory (?) sometimes masks physical memory.
1466 // If you want to change the definition of a server class machine
1467 // on some OS or platform, e.g., >=4GB on Windows platforms,
1468 // then you'll have to parameterize this method based on that state,
1469 // as was done for logical processors here, or replicate and
1470 // specialize this method for each platform. (Or fix os to have
1471 // some inheritance structure and use subclassing. Sigh.)
1472 // If you want some platform to always or never behave as a server
1473 // class machine, change the setting of AlwaysActAsServerClassMachine
1474 // and NeverActAsServerClassMachine in globals*.hpp.
1475 bool os::is_server_class_machine() {
1476 // First check for the early returns
1477 if (NeverActAsServerClassMachine) {
1478 return false;
1479 }
1480 if (AlwaysActAsServerClassMachine) {
1481 return true;
1482 }
1483 // Then actually look at the machine
1484 bool result = false;
1485 const unsigned int server_processors = 2;
1486 const julong server_memory = 2UL * G;
1487 // We seem not to get our full complement of memory.
1488 // We allow some part (1/8?) of the memory to be "missing",
1489 // based on the sizes of DIMMs, and maybe graphics cards.
1490 const julong missing_memory = 256UL * M;
1491
1492 /* Is this a server class machine? */
1493 if ((os::active_processor_count() >= (int)server_processors) &&
1494 (os::physical_memory() >= (server_memory - missing_memory))) {
1495 const unsigned int logical_processors =
1496 VM_Version::logical_processors_per_package();
1497 if (logical_processors > 1) {
1498 const unsigned int physical_packages =
1499 os::active_processor_count() / logical_processors;
1500 if (physical_packages > server_processors) {
1501 result = true;
1502 }
1503 } else {
1504 result = true;
1505 }
1506 }
1507 return result;
1508 }
1509
1510 void os::SuspendedThreadTask::run() {
1511 assert(Threads_lock->owned_by_self() || (_thread == VMThread::vm_thread()), "must have threads lock to call this");
1512 internal_do_task();
1513 _done = true;
1514 }
1515
1516 bool os::create_stack_guard_pages(char* addr, size_t bytes) {
1517 return os::pd_create_stack_guard_pages(addr, bytes);
1518 }
1519
1520 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint) {
1521 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1522 if (result != NULL) {
1523 MemTracker::record_virtual_memory_reserve((address)result, bytes, mtNone, CALLER_PC);
1524 }
1525
1526 return result;
1527 }
1528
1529 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint,
1530 MEMFLAGS flags) {
1531 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1532 if (result != NULL) {
1533 MemTracker::record_virtual_memory_reserve((address)result, bytes, mtNone, CALLER_PC);
1534 MemTracker::record_virtual_memory_type((address)result, flags);
1535 }
1536
1537 return result;
1538 }
1539
1540 char* os::attempt_reserve_memory_at(size_t bytes, char* addr) {
1541 char* result = pd_attempt_reserve_memory_at(bytes, addr);
1542 if (result != NULL) {
1543 MemTracker::record_virtual_memory_reserve((address)result, bytes, mtNone, CALLER_PC);
1544 }
1545 return result;
1546 }
1547
1548 void os::split_reserved_memory(char *base, size_t size,
1549 size_t split, bool realloc) {
1550 pd_split_reserved_memory(base, size, split, realloc);
1551 }
1552
1553 bool os::commit_memory(char* addr, size_t bytes, bool executable) {
1554 bool res = pd_commit_memory(addr, bytes, executable);
1555 if (res) {
1556 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1557 }
1558 return res;
1559 }
1560
1561 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint,
1562 bool executable) {
1563 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable);
1564 if (res) {
1565 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1566 }
1567 return res;
1568 }
1569
1570 void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable,
1571 const char* mesg) {
1572 pd_commit_memory_or_exit(addr, bytes, executable, mesg);
1573 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1574 }
1575
1576 void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint,
1577 bool executable, const char* mesg) {
1578 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg);
1579 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1580 }
1581
1582 bool os::uncommit_memory(char* addr, size_t bytes) {
1583 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_uncommit_tracker();
1584 bool res = pd_uncommit_memory(addr, bytes);
1585 if (res) {
1586 tkr.record((address)addr, bytes);
1587 } else {
1588 tkr.discard();
1589 }
1590 return res;
1591 }
1592
1593 bool os::release_memory(char* addr, size_t bytes) {
1594 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
1595 bool res = pd_release_memory(addr, bytes);
1596 if (res) {
1597 tkr.record((address)addr, bytes);
1598 } else {
1599 tkr.discard();
1600 }
1601 return res;
1602 }
1603
1604
1605 char* os::map_memory(int fd, const char* file_name, size_t file_offset,
1606 char *addr, size_t bytes, bool read_only,
1607 bool allow_exec) {
1608 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec);
1609 if (result != NULL) {
1610 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, mtNone, CALLER_PC);
1611 }
1612 return result;
1613 }
1614
1615 char* os::remap_memory(int fd, const char* file_name, size_t file_offset,
1616 char *addr, size_t bytes, bool read_only,
1617 bool allow_exec) {
1618 return pd_remap_memory(fd, file_name, file_offset, addr, bytes,
1619 read_only, allow_exec);
1620 }
1621
1622 bool os::unmap_memory(char *addr, size_t bytes) {
1623 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
1624 bool result = pd_unmap_memory(addr, bytes);
1625 if (result) {
1626 tkr.record((address)addr, bytes);
1627 } else {
1628 tkr.discard();
1629 }
1630 return result;
1631 }
1632
1633 void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) {
1634 pd_free_memory(addr, bytes, alignment_hint);
1635 }
1636
1637 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
1638 pd_realign_memory(addr, bytes, alignment_hint);
1639 }
1640
1641 #ifndef TARGET_OS_FAMILY_windows
1642 /* try to switch state from state "from" to state "to"
1643 * returns the state set after the method is complete
1644 */
1645 os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from,
1646 os::SuspendResume::State to)
1647 {
1648 os::SuspendResume::State result =
1649 (os::SuspendResume::State) Atomic::cmpxchg((jint) to, (jint *) &_state, (jint) from);
1650 if (result == from) {
1651 // success
1652 return to;
1653 }
1654 return result;
1655 }
1656 #endif