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/frame.inline.hpp"
41 #include "runtime/interfaceSupport.hpp"
42 #include "runtime/java.hpp"
43 #include "runtime/javaCalls.hpp"
44 #include "runtime/mutexLocker.hpp"
45 #include "runtime/os.hpp"
46 #include "runtime/stubRoutines.hpp"
47 #include "runtime/thread.inline.hpp"
48 #include "services/attachListener.hpp"
49 #include "services/memTracker.hpp"
50 #include "services/threadService.hpp"
51 #include "utilities/defaultStream.hpp"
52 #include "utilities/events.hpp"
53 #ifdef TARGET_OS_FAMILY_linux
54 # include "os_linux.inline.hpp"
55 #endif
56 #ifdef TARGET_OS_FAMILY_solaris
57 # include "os_solaris.inline.hpp"
58 #endif
59 #ifdef TARGET_OS_FAMILY_windows
60 # include "os_windows.inline.hpp"
61 #endif
62 #ifdef TARGET_OS_FAMILY_bsd
63 # include "os_bsd.inline.hpp"
64 #endif
65
66 # include <signal.h>
67
68 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
69
70 OSThread* os::_starting_thread = NULL;
71 address os::_polling_page = NULL;
72 volatile int32_t* os::_mem_serialize_page = NULL;
73 uintptr_t os::_serialize_page_mask = 0;
74 long os::_rand_seed = 1;
75 int os::_processor_count = 0;
76 size_t os::_page_sizes[os::page_sizes_max];
77
78 #ifndef PRODUCT
79 julong os::num_mallocs = 0; // # of calls to malloc/realloc
80 julong os::alloc_bytes = 0; // # of bytes allocated
81 julong os::num_frees = 0; // # of calls to free
82 julong os::free_bytes = 0; // # of bytes freed
83 #endif
84
85 static juint cur_malloc_words = 0; // current size for MallocMaxTestWords
86
87 void os_init_globals() {
88 // Called from init_globals().
89 // See Threads::create_vm() in thread.cpp, and init.cpp.
90 os::init_globals();
91 }
92
93 // Fill in buffer with current local time as an ISO-8601 string.
94 // E.g., yyyy-mm-ddThh:mm:ss-zzzz.
95 // Returns buffer, or NULL if it failed.
96 // This would mostly be a call to
97 // strftime(...., "%Y-%m-%d" "T" "%H:%M:%S" "%z", ....)
98 // except that on Windows the %z behaves badly, so we do it ourselves.
99 // Also, people wanted milliseconds on there,
100 // and strftime doesn't do milliseconds.
101 char* os::iso8601_time(char* buffer, size_t buffer_length) {
102 // Output will be of the form "YYYY-MM-DDThh:mm:ss.mmm+zzzz\0"
103 // 1 2
104 // 12345678901234567890123456789
105 static const char* iso8601_format =
106 "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d";
107 static const size_t needed_buffer = 29;
108
109 // Sanity check the arguments
110 if (buffer == NULL) {
111 assert(false, "NULL buffer");
112 return NULL;
113 }
114 if (buffer_length < needed_buffer) {
115 assert(false, "buffer_length too small");
116 return NULL;
117 }
118 // Get the current time
119 jlong milliseconds_since_19700101 = javaTimeMillis();
120 const int milliseconds_per_microsecond = 1000;
121 const time_t seconds_since_19700101 =
122 milliseconds_since_19700101 / milliseconds_per_microsecond;
123 const int milliseconds_after_second =
124 milliseconds_since_19700101 % milliseconds_per_microsecond;
125 // Convert the time value to a tm and timezone variable
126 struct tm time_struct;
127 if (localtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
128 assert(false, "Failed localtime_pd");
129 return NULL;
130 }
131 #if defined(_ALLBSD_SOURCE)
132 const time_t zone = (time_t) time_struct.tm_gmtoff;
133 #else
134 const time_t zone = timezone;
135 #endif
136
137 // If daylight savings time is in effect,
138 // we are 1 hour East of our time zone
139 const time_t seconds_per_minute = 60;
140 const time_t minutes_per_hour = 60;
141 const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour;
142 time_t UTC_to_local = zone;
143 if (time_struct.tm_isdst > 0) {
144 UTC_to_local = UTC_to_local - seconds_per_hour;
145 }
146 // Compute the time zone offset.
147 // localtime_pd() sets timezone to the difference (in seconds)
148 // between UTC and and local time.
149 // ISO 8601 says we need the difference between local time and UTC,
150 // we change the sign of the localtime_pd() result.
151 const time_t local_to_UTC = -(UTC_to_local);
152 // Then we have to figure out if if we are ahead (+) or behind (-) UTC.
153 char sign_local_to_UTC = '+';
154 time_t abs_local_to_UTC = local_to_UTC;
155 if (local_to_UTC < 0) {
156 sign_local_to_UTC = '-';
157 abs_local_to_UTC = -(abs_local_to_UTC);
158 }
159 // Convert time zone offset seconds to hours and minutes.
160 const time_t zone_hours = (abs_local_to_UTC / seconds_per_hour);
161 const time_t zone_min =
162 ((abs_local_to_UTC % seconds_per_hour) / seconds_per_minute);
163
164 // Print an ISO 8601 date and time stamp into the buffer
165 const int year = 1900 + time_struct.tm_year;
166 const int month = 1 + time_struct.tm_mon;
167 const int printed = jio_snprintf(buffer, buffer_length, iso8601_format,
168 year,
169 month,
170 time_struct.tm_mday,
171 time_struct.tm_hour,
172 time_struct.tm_min,
173 time_struct.tm_sec,
174 milliseconds_after_second,
175 sign_local_to_UTC,
176 zone_hours,
177 zone_min);
178 if (printed == 0) {
179 assert(false, "Failed jio_printf");
180 return NULL;
181 }
182 return buffer;
183 }
184
185 OSReturn os::set_priority(Thread* thread, ThreadPriority p) {
186 #ifdef ASSERT
187 if (!(!thread->is_Java_thread() ||
188 Thread::current() == thread ||
189 Threads_lock->owned_by_self()
190 || thread->is_Compiler_thread()
191 )) {
192 assert(false, "possibility of dangling Thread pointer");
193 }
194 #endif
195
196 if (p >= MinPriority && p <= MaxPriority) {
197 int priority = java_to_os_priority[p];
198 return set_native_priority(thread, priority);
199 } else {
200 assert(false, "Should not happen");
201 return OS_ERR;
202 }
203 }
204
205 // The mapping from OS priority back to Java priority may be inexact because
206 // Java priorities can map M:1 with native priorities. If you want the definite
207 // Java priority then use JavaThread::java_priority()
208 OSReturn os::get_priority(const Thread* const thread, ThreadPriority& priority) {
209 int p;
210 int os_prio;
211 OSReturn ret = get_native_priority(thread, &os_prio);
212 if (ret != OS_OK) return ret;
213
214 if (java_to_os_priority[MaxPriority] > java_to_os_priority[MinPriority]) {
215 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] > os_prio; p--) ;
216 } else {
217 // niceness values are in reverse order
218 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] < os_prio; p--) ;
219 }
220 priority = (ThreadPriority)p;
221 return OS_OK;
222 }
223
224
225 // --------------------- sun.misc.Signal (optional) ---------------------
226
227
228 // SIGBREAK is sent by the keyboard to query the VM state
229 #ifndef SIGBREAK
230 #define SIGBREAK SIGQUIT
231 #endif
232
233 // sigexitnum_pd is a platform-specific special signal used for terminating the Signal thread.
234
235
236 static void signal_thread_entry(JavaThread* thread, TRAPS) {
237 os::set_priority(thread, NearMaxPriority);
238 while (true) {
239 int sig;
240 {
241 // FIXME : Currently we have not decieded what should be the status
242 // for this java thread blocked here. Once we decide about
243 // that we should fix this.
244 sig = os::signal_wait();
245 }
246 if (sig == os::sigexitnum_pd()) {
247 // Terminate the signal thread
248 return;
249 }
250
251 switch (sig) {
252 case SIGBREAK: {
253 // Check if the signal is a trigger to start the Attach Listener - in that
254 // case don't print stack traces.
255 if (!DisableAttachMechanism && AttachListener::is_init_trigger()) {
256 continue;
257 }
258 // Print stack traces
259 // Any SIGBREAK operations added here should make sure to flush
260 // the output stream (e.g. tty->flush()) after output. See 4803766.
261 // Each module also prints an extra carriage return after its output.
262 VM_PrintThreads op;
263 VMThread::execute(&op);
264 VM_PrintJNI jni_op;
265 VMThread::execute(&jni_op);
266 VM_FindDeadlocks op1(tty);
267 VMThread::execute(&op1);
268 Universe::print_heap_at_SIGBREAK();
269 if (PrintClassHistogram) {
270 VM_GC_HeapInspection op1(gclog_or_tty, true /* force full GC before heap inspection */);
271 VMThread::execute(&op1);
272 }
273 if (JvmtiExport::should_post_data_dump()) {
274 JvmtiExport::post_data_dump();
275 }
276 break;
277 }
278 default: {
279 // Dispatch the signal to java
280 HandleMark hm(THREAD);
281 Klass* k = SystemDictionary::resolve_or_null(vmSymbols::sun_misc_Signal(), THREAD);
282 KlassHandle klass (THREAD, k);
283 if (klass.not_null()) {
284 JavaValue result(T_VOID);
285 JavaCallArguments args;
286 args.push_int(sig);
287 JavaCalls::call_static(
288 &result,
289 klass,
290 vmSymbols::dispatch_name(),
291 vmSymbols::int_void_signature(),
292 &args,
293 THREAD
294 );
295 }
296 if (HAS_PENDING_EXCEPTION) {
297 // tty is initialized early so we don't expect it to be null, but
298 // if it is we can't risk doing an initialization that might
299 // trigger additional out-of-memory conditions
300 if (tty != NULL) {
301 char klass_name[256];
302 char tmp_sig_name[16];
303 const char* sig_name = "UNKNOWN";
304 InstanceKlass::cast(PENDING_EXCEPTION->klass())->
305 name()->as_klass_external_name(klass_name, 256);
306 if (os::exception_name(sig, tmp_sig_name, 16) != NULL)
307 sig_name = tmp_sig_name;
308 warning("Exception %s occurred dispatching signal %s to handler"
309 "- the VM may need to be forcibly terminated",
310 klass_name, sig_name );
311 }
312 CLEAR_PENDING_EXCEPTION;
313 }
314 }
315 }
316 }
317 }
318
319 void os::init_before_ergo() {
320 // We need to initialize large page support here because ergonomics takes some
321 // decisions depending on large page support and the calculated large page size.
322 large_page_init();
323 }
324
325 void os::signal_init() {
326 if (!ReduceSignalUsage) {
327 // Setup JavaThread for processing signals
328 EXCEPTION_MARK;
329 Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(), true, CHECK);
330 instanceKlassHandle klass (THREAD, k);
331 instanceHandle thread_oop = klass->allocate_instance_handle(CHECK);
332
333 const char thread_name[] = "Signal Dispatcher";
334 Handle string = java_lang_String::create_from_str(thread_name, CHECK);
335
336 // Initialize thread_oop to put it into the system threadGroup
337 Handle thread_group (THREAD, Universe::system_thread_group());
338 JavaValue result(T_VOID);
339 JavaCalls::call_special(&result, thread_oop,
340 klass,
341 vmSymbols::object_initializer_name(),
342 vmSymbols::threadgroup_string_void_signature(),
343 thread_group,
344 string,
345 CHECK);
346
347 KlassHandle group(THREAD, SystemDictionary::ThreadGroup_klass());
348 JavaCalls::call_special(&result,
349 thread_group,
350 group,
351 vmSymbols::add_method_name(),
352 vmSymbols::thread_void_signature(),
353 thread_oop, // ARG 1
354 CHECK);
355
356 os::signal_init_pd();
357
358 { MutexLocker mu(Threads_lock);
359 JavaThread* signal_thread = new JavaThread(&signal_thread_entry);
360
361 // At this point it may be possible that no osthread was created for the
362 // JavaThread due to lack of memory. We would have to throw an exception
363 // in that case. However, since this must work and we do not allow
364 // exceptions anyway, check and abort if this fails.
365 if (signal_thread == NULL || signal_thread->osthread() == NULL) {
366 vm_exit_during_initialization("java.lang.OutOfMemoryError",
367 "unable to create new native thread");
368 }
369
370 java_lang_Thread::set_thread(thread_oop(), signal_thread);
371 java_lang_Thread::set_priority(thread_oop(), NearMaxPriority);
372 java_lang_Thread::set_daemon(thread_oop());
373
374 signal_thread->set_threadObj(thread_oop());
375 Threads::add(signal_thread);
376 Thread::start(signal_thread);
377 }
378 // Handle ^BREAK
379 os::signal(SIGBREAK, os::user_handler());
380 }
381 }
382
383
384 void os::terminate_signal_thread() {
385 if (!ReduceSignalUsage)
386 signal_notify(sigexitnum_pd());
387 }
388
389
390 // --------------------- loading libraries ---------------------
391
392 typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *);
393 extern struct JavaVM_ main_vm;
394
395 static void* _native_java_library = NULL;
396
397 void* os::native_java_library() {
398 if (_native_java_library == NULL) {
399 char buffer[JVM_MAXPATHLEN];
400 char ebuf[1024];
401
402 // Try to load verify dll first. In 1.3 java dll depends on it and is not
403 // always able to find it when the loading executable is outside the JDK.
404 // In order to keep working with 1.2 we ignore any loading errors.
405 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
406 "verify")) {
407 dll_load(buffer, ebuf, sizeof(ebuf));
408 }
409
410 // Load java dll
411 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
412 "java")) {
413 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf));
414 }
415 if (_native_java_library == NULL) {
416 vm_exit_during_initialization("Unable to load native library", ebuf);
417 }
418
419 #if defined(__OpenBSD__)
420 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so
421 // ignore errors
422 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
423 "net")) {
424 dll_load(buffer, ebuf, sizeof(ebuf));
425 }
426 #endif
427 }
428 static jboolean onLoaded = JNI_FALSE;
429 if (onLoaded) {
430 // We may have to wait to fire OnLoad until TLS is initialized.
431 if (ThreadLocalStorage::is_initialized()) {
432 // The JNI_OnLoad handling is normally done by method load in
433 // java.lang.ClassLoader$NativeLibrary, but the VM loads the base library
434 // explicitly so we have to check for JNI_OnLoad as well
435 const char *onLoadSymbols[] = JNI_ONLOAD_SYMBOLS;
436 JNI_OnLoad_t JNI_OnLoad = CAST_TO_FN_PTR(
437 JNI_OnLoad_t, dll_lookup(_native_java_library, onLoadSymbols[0]));
438 if (JNI_OnLoad != NULL) {
439 JavaThread* thread = JavaThread::current();
440 ThreadToNativeFromVM ttn(thread);
441 HandleMark hm(thread);
442 jint ver = (*JNI_OnLoad)(&main_vm, NULL);
443 onLoaded = JNI_TRUE;
444 if (!Threads::is_supported_jni_version_including_1_1(ver)) {
445 vm_exit_during_initialization("Unsupported JNI version");
446 }
447 }
448 }
449 }
450 return _native_java_library;
451 }
452
453 /*
454 * Support for finding Agent_On(Un)Load/Attach<_lib_name> if it exists.
455 * If check_lib == true then we are looking for an
456 * Agent_OnLoad_lib_name or Agent_OnAttach_lib_name function to determine if
457 * this library is statically linked into the image.
458 * If check_lib == false then we will look for the appropriate symbol in the
459 * executable if agent_lib->is_static_lib() == true or in the shared library
460 * referenced by 'handle'.
461 */
462 void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib,
463 const char *syms[], size_t syms_len) {
464 assert(agent_lib != NULL, "sanity check");
465 const char *lib_name;
466 void *handle = agent_lib->os_lib();
467 void *entryName = NULL;
468 char *agent_function_name;
469 size_t i;
470
471 // If checking then use the agent name otherwise test is_static_lib() to
472 // see how to process this lookup
473 lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL);
474 for (i = 0; i < syms_len; i++) {
475 agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path());
476 if (agent_function_name == NULL) {
477 break;
478 }
479 entryName = dll_lookup(handle, agent_function_name);
480 FREE_C_HEAP_ARRAY(char, agent_function_name, mtThread);
481 if (entryName != NULL) {
482 break;
483 }
484 }
485 return entryName;
486 }
487
488 // See if the passed in agent is statically linked into the VM image.
489 bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
490 size_t syms_len) {
491 void *ret;
492 void *proc_handle;
493 void *save_handle;
494
495 assert(agent_lib != NULL, "sanity check");
496 if (agent_lib->name() == NULL) {
497 return false;
498 }
499 proc_handle = get_default_process_handle();
500 // Check for Agent_OnLoad/Attach_lib_name function
501 save_handle = agent_lib->os_lib();
502 // We want to look in this process' symbol table.
503 agent_lib->set_os_lib(proc_handle);
504 ret = find_agent_function(agent_lib, true, syms, syms_len);
505 if (ret != NULL) {
506 // Found an entry point like Agent_OnLoad_lib_name so we have a static agent
507 agent_lib->set_valid();
508 agent_lib->set_static_lib(true);
509 return true;
510 }
511 agent_lib->set_os_lib(save_handle);
512 return false;
513 }
514
515 // --------------------- heap allocation utilities ---------------------
516
517 char *os::strdup(const char *str, MEMFLAGS flags) {
518 size_t size = strlen(str);
519 char *dup_str = (char *)malloc(size + 1, flags);
520 if (dup_str == NULL) return NULL;
521 strcpy(dup_str, str);
522 return dup_str;
523 }
524
525
526
527 #ifdef ASSERT
528 #define space_before (MallocCushion + sizeof(double))
529 #define space_after MallocCushion
530 #define size_addr_from_base(p) (size_t*)(p + space_before - sizeof(size_t))
531 #define size_addr_from_obj(p) ((size_t*)p - 1)
532 // MallocCushion: size of extra cushion allocated around objects with +UseMallocOnly
533 // NB: cannot be debug variable, because these aren't set from the command line until
534 // *after* the first few allocs already happened
535 #define MallocCushion 16
536 #else
537 #define space_before 0
538 #define space_after 0
539 #define size_addr_from_base(p) should not use w/o ASSERT
540 #define size_addr_from_obj(p) should not use w/o ASSERT
541 #define MallocCushion 0
542 #endif
543 #define paranoid 0 /* only set to 1 if you suspect checking code has bug */
544
545 #ifdef ASSERT
546 inline size_t get_size(void* obj) {
547 size_t size = *size_addr_from_obj(obj);
548 if (size < 0) {
549 fatal(err_msg("free: size field of object #" PTR_FORMAT " was overwritten ("
550 SIZE_FORMAT ")", obj, size));
551 }
552 return size;
553 }
554
555 u_char* find_cushion_backwards(u_char* start) {
556 u_char* p = start;
557 while (p[ 0] != badResourceValue || p[-1] != badResourceValue ||
558 p[-2] != badResourceValue || p[-3] != badResourceValue) p--;
559 // ok, we have four consecutive marker bytes; find start
560 u_char* q = p - 4;
561 while (*q == badResourceValue) q--;
562 return q + 1;
563 }
564
565 u_char* find_cushion_forwards(u_char* start) {
566 u_char* p = start;
567 while (p[0] != badResourceValue || p[1] != badResourceValue ||
568 p[2] != badResourceValue || p[3] != badResourceValue) p++;
569 // ok, we have four consecutive marker bytes; find end of cushion
570 u_char* q = p + 4;
571 while (*q == badResourceValue) q++;
572 return q - MallocCushion;
573 }
574
575 void print_neighbor_blocks(void* ptr) {
576 // find block allocated before ptr (not entirely crash-proof)
577 if (MallocCushion < 4) {
578 tty->print_cr("### cannot find previous block (MallocCushion < 4)");
579 return;
580 }
581 u_char* start_of_this_block = (u_char*)ptr - space_before;
582 u_char* end_of_prev_block_data = start_of_this_block - space_after -1;
583 // look for cushion in front of prev. block
584 u_char* start_of_prev_block = find_cushion_backwards(end_of_prev_block_data);
585 ptrdiff_t size = *size_addr_from_base(start_of_prev_block);
586 u_char* obj = start_of_prev_block + space_before;
587 if (size <= 0 ) {
588 // start is bad; mayhave been confused by OS data inbetween objects
589 // search one more backwards
590 start_of_prev_block = find_cushion_backwards(start_of_prev_block);
591 size = *size_addr_from_base(start_of_prev_block);
592 obj = start_of_prev_block + space_before;
593 }
594
595 if (start_of_prev_block + space_before + size + space_after == start_of_this_block) {
596 tty->print_cr("### previous object: " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", obj, size);
597 } else {
598 tty->print_cr("### previous object (not sure if correct): " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", obj, size);
599 }
600
601 // now find successor block
602 u_char* start_of_next_block = (u_char*)ptr + *size_addr_from_obj(ptr) + space_after;
603 start_of_next_block = find_cushion_forwards(start_of_next_block);
604 u_char* next_obj = start_of_next_block + space_before;
605 ptrdiff_t next_size = *size_addr_from_base(start_of_next_block);
606 if (start_of_next_block[0] == badResourceValue &&
607 start_of_next_block[1] == badResourceValue &&
608 start_of_next_block[2] == badResourceValue &&
609 start_of_next_block[3] == badResourceValue) {
610 tty->print_cr("### next object: " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", next_obj, next_size);
611 } else {
612 tty->print_cr("### next object (not sure if correct): " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", next_obj, next_size);
613 }
614 }
615
616
617 void report_heap_error(void* memblock, void* bad, const char* where) {
618 tty->print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees);
619 tty->print_cr("## memory stomp: byte at " PTR_FORMAT " %s object " PTR_FORMAT, bad, where, memblock);
620 print_neighbor_blocks(memblock);
621 fatal("memory stomping error");
622 }
623
624 void verify_block(void* memblock) {
625 size_t size = get_size(memblock);
626 if (MallocCushion) {
627 u_char* ptr = (u_char*)memblock - space_before;
628 for (int i = 0; i < MallocCushion; i++) {
629 if (ptr[i] != badResourceValue) {
630 report_heap_error(memblock, ptr+i, "in front of");
631 }
632 }
633 u_char* end = (u_char*)memblock + size + space_after;
634 for (int j = -MallocCushion; j < 0; j++) {
635 if (end[j] != badResourceValue) {
636 report_heap_error(memblock, end+j, "after");
637 }
638 }
639 }
640 }
641 #endif
642
643 //
644 // This function supports testing of the malloc out of memory
645 // condition without really running the system out of memory.
646 //
647 static u_char* testMalloc(size_t alloc_size) {
648 assert(MallocMaxTestWords > 0, "sanity check");
649
650 if ((cur_malloc_words + (alloc_size / BytesPerWord)) > MallocMaxTestWords) {
651 return NULL;
652 }
653
654 u_char* ptr = (u_char*)::malloc(alloc_size);
655
656 if (ptr != NULL) {
657 Atomic::add(((jint) (alloc_size / BytesPerWord)),
658 (volatile jint *) &cur_malloc_words);
659 }
660 return ptr;
661 }
662
663 void* os::malloc(size_t size, MEMFLAGS memflags, address caller) {
664 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
665 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
666
667 #ifdef ASSERT
668 // checking for the WatcherThread and crash_protection first
669 // since os::malloc can be called when the libjvm.{dll,so} is
670 // first loaded and we don't have a thread yet.
671 // try to find the thread after we see that the watcher thread
672 // exists and has crash protection.
673 WatcherThread *wt = WatcherThread::watcher_thread();
674 if (wt != NULL && wt->has_crash_protection()) {
675 Thread* thread = ThreadLocalStorage::get_thread_slow();
676 if (thread == wt) {
677 assert(!wt->has_crash_protection(),
678 "Can't malloc with crash protection from WatcherThread");
679 }
680 }
681 #endif
682
683 if (size == 0) {
684 // return a valid pointer if size is zero
685 // if NULL is returned the calling functions assume out of memory.
686 size = 1;
687 }
688
689 const size_t alloc_size = size + space_before + space_after;
690
691 if (size > alloc_size) { // Check for rollover.
692 return NULL;
693 }
694
695 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
696
697 u_char* ptr;
698
699 if (MallocMaxTestWords > 0) {
700 ptr = testMalloc(alloc_size);
701 } else {
702 ptr = (u_char*)::malloc(alloc_size);
703 }
704
705 #ifdef ASSERT
706 if (ptr == NULL) return NULL;
707 if (MallocCushion) {
708 for (u_char* p = ptr; p < ptr + MallocCushion; p++) *p = (u_char)badResourceValue;
709 u_char* end = ptr + space_before + size;
710 for (u_char* pq = ptr+MallocCushion; pq < end; pq++) *pq = (u_char)uninitBlockPad;
711 for (u_char* q = end; q < end + MallocCushion; q++) *q = (u_char)badResourceValue;
712 }
713 // put size just before data
714 *size_addr_from_base(ptr) = size;
715 #endif
716 u_char* memblock = ptr + space_before;
717 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
718 tty->print_cr("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, memblock);
719 breakpoint();
720 }
721 debug_only(if (paranoid) verify_block(memblock));
722 if (PrintMalloc && tty != NULL) tty->print_cr("os::malloc " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, memblock);
723
724 // we do not track MallocCushion memory
725 MemTracker::record_malloc((address)memblock, size, memflags, caller == 0 ? CALLER_PC : caller);
726
727 return memblock;
728 }
729
730
731 void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, address caller) {
732 #ifndef ASSERT
733 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
734 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
735 MemTracker::Tracker tkr = MemTracker::get_realloc_tracker();
736 void* ptr = ::realloc(memblock, size);
737 if (ptr != NULL) {
738 tkr.record((address)memblock, (address)ptr, size, memflags,
739 caller == 0 ? CALLER_PC : caller);
740 } else {
741 tkr.discard();
742 }
743 return ptr;
744 #else
745 if (memblock == NULL) {
746 return malloc(size, memflags, (caller == 0 ? CALLER_PC : caller));
747 }
748 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
749 tty->print_cr("os::realloc caught " PTR_FORMAT, memblock);
750 breakpoint();
751 }
752 verify_block(memblock);
753 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
754 if (size == 0) return NULL;
755 // always move the block
756 void* ptr = malloc(size, memflags, caller == 0 ? CALLER_PC : caller);
757 if (PrintMalloc) tty->print_cr("os::remalloc " SIZE_FORMAT " bytes, " PTR_FORMAT " --> " PTR_FORMAT, size, memblock, ptr);
758 // Copy to new memory if malloc didn't fail
759 if ( ptr != NULL ) {
760 memcpy(ptr, memblock, MIN2(size, get_size(memblock)));
761 if (paranoid) verify_block(ptr);
762 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) {
763 tty->print_cr("os::realloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr);
764 breakpoint();
765 }
766 free(memblock);
767 }
768 return ptr;
769 #endif
770 }
771
772
773 void os::free(void *memblock, MEMFLAGS memflags) {
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 if (tty != NULL) tty->print_cr("os::free caught " PTR_FORMAT, memblock);
779 breakpoint();
780 }
781 verify_block(memblock);
782 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
783 // Added by detlefs.
784 if (MallocCushion) {
785 u_char* ptr = (u_char*)memblock - space_before;
786 for (u_char* p = ptr; p < ptr + MallocCushion; p++) {
787 guarantee(*p == badResourceValue,
788 "Thing freed should be malloc result.");
789 *p = (u_char)freeBlockPad;
790 }
791 size_t size = get_size(memblock);
792 inc_stat_counter(&free_bytes, size);
793 u_char* end = ptr + space_before + size;
794 for (u_char* q = end; q < end + MallocCushion; q++) {
795 guarantee(*q == badResourceValue,
796 "Thing freed should be malloc result.");
797 *q = (u_char)freeBlockPad;
798 }
799 if (PrintMalloc && tty != NULL)
800 fprintf(stderr, "os::free " SIZE_FORMAT " bytes --> " PTR_FORMAT "\n", size, (uintptr_t)memblock);
801 } else if (PrintMalloc && tty != NULL) {
802 // tty->print_cr("os::free %p", memblock);
803 fprintf(stderr, "os::free " PTR_FORMAT "\n", (uintptr_t)memblock);
804 }
805 #endif
806 MemTracker::record_free((address)memblock, memflags);
807
808 ::free((char*)memblock - space_before);
809 }
810
811 void os::init_random(long initval) {
812 _rand_seed = initval;
813 }
814
815
816 long os::random() {
817 /* standard, well-known linear congruential random generator with
818 * next_rand = (16807*seed) mod (2**31-1)
819 * see
820 * (1) "Random Number Generators: Good Ones Are Hard to Find",
821 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988),
822 * (2) "Two Fast Implementations of the 'Minimal Standard' Random
823 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88.
824 */
825 const long a = 16807;
826 const unsigned long m = 2147483647;
827 const long q = m / a; assert(q == 127773, "weird math");
828 const long r = m % a; assert(r == 2836, "weird math");
829
830 // compute az=2^31p+q
831 unsigned long lo = a * (long)(_rand_seed & 0xFFFF);
832 unsigned long hi = a * (long)((unsigned long)_rand_seed >> 16);
833 lo += (hi & 0x7FFF) << 16;
834
835 // if q overflowed, ignore the overflow and increment q
836 if (lo > m) {
837 lo &= m;
838 ++lo;
839 }
840 lo += hi >> 15;
841
842 // if (p+q) overflowed, ignore the overflow and increment (p+q)
843 if (lo > m) {
844 lo &= m;
845 ++lo;
846 }
847 return (_rand_seed = lo);
848 }
849
850 // The INITIALIZED state is distinguished from the SUSPENDED state because the
851 // conditions in which a thread is first started are different from those in which
852 // a suspension is resumed. These differences make it hard for us to apply the
853 // tougher checks when starting threads that we want to do when resuming them.
854 // However, when start_thread is called as a result of Thread.start, on a Java
855 // thread, the operation is synchronized on the Java Thread object. So there
856 // cannot be a race to start the thread and hence for the thread to exit while
857 // we are working on it. Non-Java threads that start Java threads either have
858 // to do so in a context in which races are impossible, or should do appropriate
859 // locking.
860
861 void os::start_thread(Thread* thread) {
862 // guard suspend/resume
863 MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag);
864 OSThread* osthread = thread->osthread();
865 osthread->set_state(RUNNABLE);
866 pd_start_thread(thread);
867 }
868
869 //---------------------------------------------------------------------------
870 // Helper functions for fatal error handler
871
872 void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) {
873 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking");
874
875 int cols = 0;
876 int cols_per_line = 0;
877 switch (unitsize) {
878 case 1: cols_per_line = 16; break;
879 case 2: cols_per_line = 8; break;
880 case 4: cols_per_line = 4; break;
881 case 8: cols_per_line = 2; break;
882 default: return;
883 }
884
885 address p = start;
886 st->print(PTR_FORMAT ": ", start);
887 while (p < end) {
888 switch (unitsize) {
889 case 1: st->print("%02x", *(u1*)p); break;
890 case 2: st->print("%04x", *(u2*)p); break;
891 case 4: st->print("%08x", *(u4*)p); break;
892 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break;
893 }
894 p += unitsize;
895 cols++;
896 if (cols >= cols_per_line && p < end) {
897 cols = 0;
898 st->cr();
899 st->print(PTR_FORMAT ": ", p);
900 } else {
901 st->print(" ");
902 }
903 }
904 st->cr();
905 }
906
907 void os::print_environment_variables(outputStream* st, const char** env_list,
908 char* buffer, int len) {
909 if (env_list) {
910 st->print_cr("Environment Variables:");
911
912 for (int i = 0; env_list[i] != NULL; i++) {
913 if (getenv(env_list[i], buffer, len)) {
914 st->print("%s", env_list[i]);
915 st->print("=");
916 st->print_cr("%s", buffer);
917 }
918 }
919 }
920 }
921
922 void os::print_cpu_info(outputStream* st) {
923 // cpu
924 st->print("CPU:");
925 st->print("total %d", os::processor_count());
926 // It's not safe to query number of active processors after crash
927 // st->print("(active %d)", os::active_processor_count());
928 st->print(" %s", VM_Version::cpu_features());
929 st->cr();
930 pd_print_cpu_info(st);
931 }
932
933 void os::print_date_and_time(outputStream *st) {
934 const int secs_per_day = 86400;
935 const int secs_per_hour = 3600;
936 const int secs_per_min = 60;
937
938 time_t tloc;
939 (void)time(&tloc);
940 st->print("time: %s", ctime(&tloc)); // ctime adds newline.
941
942 double t = os::elapsedTime();
943 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in
944 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int
945 // before printf. We lost some precision, but who cares?
946 int eltime = (int)t; // elapsed time in seconds
947
948 // print elapsed time in a human-readable format:
949 int eldays = eltime / secs_per_day;
950 int day_secs = eldays * secs_per_day;
951 int elhours = (eltime - day_secs) / secs_per_hour;
952 int hour_secs = elhours * secs_per_hour;
953 int elmins = (eltime - day_secs - hour_secs) / secs_per_min;
954 int minute_secs = elmins * secs_per_min;
955 int elsecs = (eltime - day_secs - hour_secs - minute_secs);
956 st->print_cr("elapsed time: %d seconds (%dd %dh %dm %ds)", eltime, eldays, elhours, elmins, elsecs);
957 }
958
959 // moved from debug.cpp (used to be find()) but still called from there
960 // The verbose parameter is only set by the debug code in one case
961 void os::print_location(outputStream* st, intptr_t x, bool verbose) {
962 address addr = (address)x;
963 CodeBlob* b = CodeCache::find_blob_unsafe(addr);
964 if (b != NULL) {
965 if (b->is_buffer_blob()) {
966 // the interpreter is generated into a buffer blob
967 InterpreterCodelet* i = Interpreter::codelet_containing(addr);
968 if (i != NULL) {
969 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an Interpreter codelet", addr, (int)(addr - i->code_begin()));
970 i->print_on(st);
971 return;
972 }
973 if (Interpreter::contains(addr)) {
974 st->print_cr(INTPTR_FORMAT " is pointing into interpreter code"
975 " (not bytecode specific)", addr);
976 return;
977 }
978 //
979 if (AdapterHandlerLibrary::contains(b)) {
980 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an AdapterHandler", addr, (int)(addr - b->code_begin()));
981 AdapterHandlerLibrary::print_handler_on(st, b);
982 }
983 // the stubroutines are generated into a buffer blob
984 StubCodeDesc* d = StubCodeDesc::desc_for(addr);
985 if (d != NULL) {
986 st->print_cr(INTPTR_FORMAT " is at begin+%d in a stub", addr, (int)(addr - d->begin()));
987 d->print_on(st);
988 st->cr();
989 return;
990 }
991 if (StubRoutines::contains(addr)) {
992 st->print_cr(INTPTR_FORMAT " is pointing to an (unnamed) "
993 "stub routine", addr);
994 return;
995 }
996 // the InlineCacheBuffer is using stubs generated into a buffer blob
997 if (InlineCacheBuffer::contains(addr)) {
998 st->print_cr(INTPTR_FORMAT " is pointing into InlineCacheBuffer", addr);
999 return;
1000 }
1001 VtableStub* v = VtableStubs::stub_containing(addr);
1002 if (v != NULL) {
1003 st->print_cr(INTPTR_FORMAT " is at entry_point+%d in a vtable stub", addr, (int)(addr - v->entry_point()));
1004 v->print_on(st);
1005 st->cr();
1006 return;
1007 }
1008 }
1009 nmethod* nm = b->as_nmethod_or_null();
1010 if (nm != NULL) {
1011 ResourceMark rm;
1012 st->print(INTPTR_FORMAT " is at entry_point+%d in (nmethod*)" INTPTR_FORMAT,
1013 addr, (int)(addr - nm->entry_point()), nm);
1014 if (verbose) {
1015 st->print(" for ");
1016 nm->method()->print_value_on(st);
1017 }
1018 st->cr();
1019 nm->print_nmethod(verbose);
1020 return;
1021 }
1022 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in ", addr, (int)(addr - b->code_begin()));
1023 b->print_on(st);
1024 return;
1025 }
1026
1027 if (Universe::heap()->is_in(addr)) {
1028 HeapWord* p = Universe::heap()->block_start(addr);
1029 bool print = false;
1030 // If we couldn't find it it just may mean that heap wasn't parseable
1031 // See if we were just given an oop directly
1032 if (p != NULL && Universe::heap()->block_is_obj(p)) {
1033 print = true;
1034 } else if (p == NULL && ((oopDesc*)addr)->is_oop()) {
1035 p = (HeapWord*) addr;
1036 print = true;
1037 }
1038 if (print) {
1039 if (p == (HeapWord*) addr) {
1040 st->print_cr(INTPTR_FORMAT " is an oop", addr);
1041 } else {
1042 st->print_cr(INTPTR_FORMAT " is pointing into object: " INTPTR_FORMAT, addr, p);
1043 }
1044 oop(p)->print_on(st);
1045 return;
1046 }
1047 } else {
1048 if (Universe::heap()->is_in_reserved(addr)) {
1049 st->print_cr(INTPTR_FORMAT " is an unallocated location "
1050 "in the heap", addr);
1051 return;
1052 }
1053 }
1054 if (JNIHandles::is_global_handle((jobject) addr)) {
1055 st->print_cr(INTPTR_FORMAT " is a global jni handle", addr);
1056 return;
1057 }
1058 if (JNIHandles::is_weak_global_handle((jobject) addr)) {
1059 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", addr);
1060 return;
1061 }
1062 #ifndef PRODUCT
1063 // we don't keep the block list in product mode
1064 if (JNIHandleBlock::any_contains((jobject) addr)) {
1065 st->print_cr(INTPTR_FORMAT " is a local jni handle", addr);
1066 return;
1067 }
1068 #endif
1069
1070 for(JavaThread *thread = Threads::first(); thread; thread = thread->next()) {
1071 // Check for privilege stack
1072 if (thread->privileged_stack_top() != NULL &&
1073 thread->privileged_stack_top()->contains(addr)) {
1074 st->print_cr(INTPTR_FORMAT " is pointing into the privilege stack "
1075 "for thread: " INTPTR_FORMAT, addr, thread);
1076 if (verbose) thread->print_on(st);
1077 return;
1078 }
1079 // If the addr is a java thread print information about that.
1080 if (addr == (address)thread) {
1081 if (verbose) {
1082 thread->print_on(st);
1083 } else {
1084 st->print_cr(INTPTR_FORMAT " is a thread", addr);
1085 }
1086 return;
1087 }
1088 // If the addr is in the stack region for this thread then report that
1089 // and print thread info
1090 if (thread->stack_base() >= addr &&
1091 addr > (thread->stack_base() - thread->stack_size())) {
1092 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: "
1093 INTPTR_FORMAT, addr, thread);
1094 if (verbose) thread->print_on(st);
1095 return;
1096 }
1097
1098 }
1099
1100 // Check if in metaspace and print types that have vptrs (only method now)
1101 if (Metaspace::contains(addr)) {
1102 if (Method::has_method_vptr((const void*)addr)) {
1103 ((Method*)addr)->print_value_on(st);
1104 st->cr();
1105 } else {
1106 // Use addr->print() from the debugger instead (not here)
1107 st->print_cr(INTPTR_FORMAT " is pointing into metadata", addr);
1108 }
1109 return;
1110 }
1111
1112 // Try an OS specific find
1113 if (os::find(addr, st)) {
1114 return;
1115 }
1116
1117 st->print_cr(INTPTR_FORMAT " is an unknown value", addr);
1118 }
1119
1120 // Looks like all platforms except IA64 can use the same function to check
1121 // if C stack is walkable beyond current frame. The check for fp() is not
1122 // necessary on Sparc, but it's harmless.
1123 bool os::is_first_C_frame(frame* fr) {
1124 #if (defined(IA64) && !defined(AIX)) && !defined(_WIN32)
1125 // On IA64 we have to check if the callers bsp is still valid
1126 // (i.e. within the register stack bounds).
1127 // Notice: this only works for threads created by the VM and only if
1128 // we walk the current stack!!! If we want to be able to walk
1129 // arbitrary other threads, we'll have to somehow store the thread
1130 // object in the frame.
1131 Thread *thread = Thread::current();
1132 if ((address)fr->fp() <=
1133 thread->register_stack_base() HPUX_ONLY(+ 0x0) LINUX_ONLY(+ 0x50)) {
1134 // This check is a little hacky, because on Linux the first C
1135 // frame's ('start_thread') register stack frame starts at
1136 // "register_stack_base + 0x48" while on HPUX, the first C frame's
1137 // ('__pthread_bound_body') register stack frame seems to really
1138 // start at "register_stack_base".
1139 return true;
1140 } else {
1141 return false;
1142 }
1143 #elif defined(IA64) && defined(_WIN32)
1144 return true;
1145 #else
1146 // Load up sp, fp, sender sp and sender fp, check for reasonable values.
1147 // Check usp first, because if that's bad the other accessors may fault
1148 // on some architectures. Ditto ufp second, etc.
1149 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1);
1150 // sp on amd can be 32 bit aligned.
1151 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1);
1152
1153 uintptr_t usp = (uintptr_t)fr->sp();
1154 if ((usp & sp_align_mask) != 0) return true;
1155
1156 uintptr_t ufp = (uintptr_t)fr->fp();
1157 if ((ufp & fp_align_mask) != 0) return true;
1158
1159 uintptr_t old_sp = (uintptr_t)fr->sender_sp();
1160 if ((old_sp & sp_align_mask) != 0) return true;
1161 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true;
1162
1163 uintptr_t old_fp = (uintptr_t)fr->link();
1164 if ((old_fp & fp_align_mask) != 0) return true;
1165 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true;
1166
1167 // stack grows downwards; if old_fp is below current fp or if the stack
1168 // frame is too large, either the stack is corrupted or fp is not saved
1169 // on stack (i.e. on x86, ebp may be used as general register). The stack
1170 // is not walkable beyond current frame.
1171 if (old_fp < ufp) return true;
1172 if (old_fp - ufp > 64 * K) return true;
1173
1174 return false;
1175 #endif
1176 }
1177
1178 #ifdef ASSERT
1179 extern "C" void test_random() {
1180 const double m = 2147483647;
1181 double mean = 0.0, variance = 0.0, t;
1182 long reps = 10000;
1183 unsigned long seed = 1;
1184
1185 tty->print_cr("seed %ld for %ld repeats...", seed, reps);
1186 os::init_random(seed);
1187 long num;
1188 for (int k = 0; k < reps; k++) {
1189 num = os::random();
1190 double u = (double)num / m;
1191 assert(u >= 0.0 && u <= 1.0, "bad random number!");
1192
1193 // calculate mean and variance of the random sequence
1194 mean += u;
1195 variance += (u*u);
1196 }
1197 mean /= reps;
1198 variance /= (reps - 1);
1199
1200 assert(num == 1043618065, "bad seed");
1201 tty->print_cr("mean of the 1st 10000 numbers: %f", mean);
1202 tty->print_cr("variance of the 1st 10000 numbers: %f", variance);
1203 const double eps = 0.0001;
1204 t = fabsd(mean - 0.5018);
1205 assert(t < eps, "bad mean");
1206 t = (variance - 0.3355) < 0.0 ? -(variance - 0.3355) : variance - 0.3355;
1207 assert(t < eps, "bad variance");
1208 }
1209 #endif
1210
1211
1212 // Set up the boot classpath.
1213
1214 char* os::format_boot_path(const char* format_string,
1215 const char* home,
1216 int home_len,
1217 char fileSep,
1218 char pathSep) {
1219 assert((fileSep == '/' && pathSep == ':') ||
1220 (fileSep == '\\' && pathSep == ';'), "unexpected seperator chars");
1221
1222 // Scan the format string to determine the length of the actual
1223 // boot classpath, and handle platform dependencies as well.
1224 int formatted_path_len = 0;
1225 const char* p;
1226 for (p = format_string; *p != 0; ++p) {
1227 if (*p == '%') formatted_path_len += home_len - 1;
1228 ++formatted_path_len;
1229 }
1230
1231 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal);
1232 if (formatted_path == NULL) {
1233 return NULL;
1234 }
1235
1236 // Create boot classpath from format, substituting separator chars and
1237 // java home directory.
1238 char* q = formatted_path;
1239 for (p = format_string; *p != 0; ++p) {
1240 switch (*p) {
1241 case '%':
1242 strcpy(q, home);
1243 q += home_len;
1244 break;
1245 case '/':
1246 *q++ = fileSep;
1247 break;
1248 case ':':
1249 *q++ = pathSep;
1250 break;
1251 default:
1252 *q++ = *p;
1253 }
1254 }
1255 *q = '\0';
1256
1257 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched");
1258 return formatted_path;
1259 }
1260
1261
1262 bool os::set_boot_path(char fileSep, char pathSep) {
1263 const char* home = Arguments::get_java_home();
1264 int home_len = (int)strlen(home);
1265
1266 static const char* meta_index_dir_format = "%/lib/";
1267 static const char* meta_index_format = "%/lib/meta-index";
1268 char* meta_index = format_boot_path(meta_index_format, home, home_len, fileSep, pathSep);
1269 if (meta_index == NULL) return false;
1270 char* meta_index_dir = format_boot_path(meta_index_dir_format, home, home_len, fileSep, pathSep);
1271 if (meta_index_dir == NULL) return false;
1272 Arguments::set_meta_index_path(meta_index, meta_index_dir);
1273
1274 // Any modification to the JAR-file list, for the boot classpath must be
1275 // aligned with install/install/make/common/Pack.gmk. Note: boot class
1276 // path class JARs, are stripped for StackMapTable to reduce download size.
1277 static const char classpath_format[] =
1278 "%/lib/resources.jar:"
1279 "%/lib/rt.jar:"
1280 "%/lib/sunrsasign.jar:"
1281 "%/lib/jsse.jar:"
1282 "%/lib/jce.jar:"
1283 "%/lib/charsets.jar:"
1284 "%/lib/jfr.jar:"
1285 "%/classes";
1286 char* sysclasspath = format_boot_path(classpath_format, home, home_len, fileSep, pathSep);
1287 if (sysclasspath == NULL) return false;
1288 Arguments::set_sysclasspath(sysclasspath);
1289
1290 return true;
1291 }
1292
1293 /*
1294 * Splits a path, based on its separator, the number of
1295 * elements is returned back in n.
1296 * It is the callers responsibility to:
1297 * a> check the value of n, and n may be 0.
1298 * b> ignore any empty path elements
1299 * c> free up the data.
1300 */
1301 char** os::split_path(const char* path, int* n) {
1302 *n = 0;
1303 if (path == NULL || strlen(path) == 0) {
1304 return NULL;
1305 }
1306 const char psepchar = *os::path_separator();
1307 char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal);
1308 if (inpath == NULL) {
1309 return NULL;
1310 }
1311 strcpy(inpath, path);
1312 int count = 1;
1313 char* p = strchr(inpath, psepchar);
1314 // Get a count of elements to allocate memory
1315 while (p != NULL) {
1316 count++;
1317 p++;
1318 p = strchr(p, psepchar);
1319 }
1320 char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count, mtInternal);
1321 if (opath == NULL) {
1322 return NULL;
1323 }
1324
1325 // do the actual splitting
1326 p = inpath;
1327 for (int i = 0 ; i < count ; i++) {
1328 size_t len = strcspn(p, os::path_separator());
1329 if (len > JVM_MAXPATHLEN) {
1330 return NULL;
1331 }
1332 // allocate the string and add terminator storage
1333 char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
1334 if (s == NULL) {
1335 return NULL;
1336 }
1337 strncpy(s, p, len);
1338 s[len] = '\0';
1339 opath[i] = s;
1340 p += len + 1;
1341 }
1342 FREE_C_HEAP_ARRAY(char, inpath, mtInternal);
1343 *n = count;
1344 return opath;
1345 }
1346
1347 void os::set_memory_serialize_page(address page) {
1348 int count = log2_intptr(sizeof(class JavaThread)) - log2_intptr(64);
1349 _mem_serialize_page = (volatile int32_t *)page;
1350 // We initialize the serialization page shift count here
1351 // We assume a cache line size of 64 bytes
1352 assert(SerializePageShiftCount == count,
1353 "thread size changed, fix SerializePageShiftCount constant");
1354 set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t)));
1355 }
1356
1357 static volatile intptr_t SerializePageLock = 0;
1358
1359 // This method is called from signal handler when SIGSEGV occurs while the current
1360 // thread tries to store to the "read-only" memory serialize page during state
1361 // transition.
1362 void os::block_on_serialize_page_trap() {
1363 if (TraceSafepoint) {
1364 tty->print_cr("Block until the serialize page permission restored");
1365 }
1366 // When VMThread is holding the SerializePageLock during modifying the
1367 // access permission of the memory serialize page, the following call
1368 // will block until the permission of that page is restored to rw.
1369 // Generally, it is unsafe to manipulate locks in signal handlers, but in
1370 // this case, it's OK as the signal is synchronous and we know precisely when
1371 // it can occur.
1372 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page");
1373 Thread::muxRelease(&SerializePageLock);
1374 }
1375
1376 // Serialize all thread state variables
1377 void os::serialize_thread_states() {
1378 // On some platforms such as Solaris & Linux, the time duration of the page
1379 // permission restoration is observed to be much longer than expected due to
1380 // scheduler starvation problem etc. To avoid the long synchronization
1381 // time and expensive page trap spinning, 'SerializePageLock' is used to block
1382 // the mutator thread if such case is encountered. See bug 6546278 for details.
1383 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states");
1384 os::protect_memory((char *)os::get_memory_serialize_page(),
1385 os::vm_page_size(), MEM_PROT_READ);
1386 os::protect_memory((char *)os::get_memory_serialize_page(),
1387 os::vm_page_size(), MEM_PROT_RW);
1388 Thread::muxRelease(&SerializePageLock);
1389 }
1390
1391 // Returns true if the current stack pointer is above the stack shadow
1392 // pages, false otherwise.
1393
1394 bool os::stack_shadow_pages_available(Thread *thread, methodHandle method) {
1395 assert(StackRedPages > 0 && StackYellowPages > 0,"Sanity check");
1396 address sp = current_stack_pointer();
1397 // Check if we have StackShadowPages above the yellow zone. This parameter
1398 // is dependent on the depth of the maximum VM call stack possible from
1399 // the handler for stack overflow. 'instanceof' in the stack overflow
1400 // handler or a println uses at least 8k stack of VM and native code
1401 // respectively.
1402 const int framesize_in_bytes =
1403 Interpreter::size_top_interpreter_activation(method()) * wordSize;
1404 int reserved_area = ((StackShadowPages + StackRedPages + StackYellowPages)
1405 * vm_page_size()) + framesize_in_bytes;
1406 // The very lower end of the stack
1407 address stack_limit = thread->stack_base() - thread->stack_size();
1408 return (sp > (stack_limit + reserved_area));
1409 }
1410
1411 size_t os::page_size_for_region(size_t region_min_size, size_t region_max_size,
1412 uint min_pages)
1413 {
1414 assert(min_pages > 0, "sanity");
1415 if (UseLargePages) {
1416 const size_t max_page_size = region_max_size / min_pages;
1417
1418 for (unsigned int i = 0; _page_sizes[i] != 0; ++i) {
1419 const size_t sz = _page_sizes[i];
1420 const size_t mask = sz - 1;
1421 if ((region_min_size & mask) == 0 && (region_max_size & mask) == 0) {
1422 // The largest page size with no fragmentation.
1423 return sz;
1424 }
1425
1426 if (sz <= max_page_size) {
1427 // The largest page size that satisfies the min_pages requirement.
1428 return sz;
1429 }
1430 }
1431 }
1432
1433 return vm_page_size();
1434 }
1435
1436 #ifndef PRODUCT
1437 void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count)
1438 {
1439 if (TracePageSizes) {
1440 tty->print("%s: ", str);
1441 for (int i = 0; i < count; ++i) {
1442 tty->print(" " SIZE_FORMAT, page_sizes[i]);
1443 }
1444 tty->cr();
1445 }
1446 }
1447
1448 void os::trace_page_sizes(const char* str, const size_t region_min_size,
1449 const size_t region_max_size, const size_t page_size,
1450 const char* base, const size_t size)
1451 {
1452 if (TracePageSizes) {
1453 tty->print_cr("%s: min=" SIZE_FORMAT " max=" SIZE_FORMAT
1454 " pg_sz=" SIZE_FORMAT " base=" PTR_FORMAT
1455 " size=" SIZE_FORMAT,
1456 str, region_min_size, region_max_size,
1457 page_size, base, size);
1458 }
1459 }
1460 #endif // #ifndef PRODUCT
1461
1462 // This is the working definition of a server class machine:
1463 // >= 2 physical CPU's and >=2GB of memory, with some fuzz
1464 // because the graphics memory (?) sometimes masks physical memory.
1465 // If you want to change the definition of a server class machine
1466 // on some OS or platform, e.g., >=4GB on Windohs platforms,
1467 // then you'll have to parameterize this method based on that state,
1468 // as was done for logical processors here, or replicate and
1469 // specialize this method for each platform. (Or fix os to have
1470 // some inheritance structure and use subclassing. Sigh.)
1471 // If you want some platform to always or never behave as a server
1472 // class machine, change the setting of AlwaysActAsServerClassMachine
1473 // and NeverActAsServerClassMachine in globals*.hpp.
1474 bool os::is_server_class_machine() {
1475 // First check for the early returns
1476 if (NeverActAsServerClassMachine) {
1477 return false;
1478 }
1479 if (AlwaysActAsServerClassMachine) {
1480 return true;
1481 }
1482 // Then actually look at the machine
1483 bool result = false;
1484 const unsigned int server_processors = 2;
1485 const julong server_memory = 2UL * G;
1486 // We seem not to get our full complement of memory.
1487 // We allow some part (1/8?) of the memory to be "missing",
1488 // based on the sizes of DIMMs, and maybe graphics cards.
1489 const julong missing_memory = 256UL * M;
1490
1491 /* Is this a server class machine? */
1492 if ((os::active_processor_count() >= (int)server_processors) &&
1493 (os::physical_memory() >= (server_memory - missing_memory))) {
1494 const unsigned int logical_processors =
1495 VM_Version::logical_processors_per_package();
1496 if (logical_processors > 1) {
1497 const unsigned int physical_packages =
1498 os::active_processor_count() / logical_processors;
1499 if (physical_packages > server_processors) {
1500 result = true;
1501 }
1502 } else {
1503 result = true;
1504 }
1505 }
1506 return result;
1507 }
1508
1509 void os::SuspendedThreadTask::run() {
1510 assert(Threads_lock->owned_by_self() || (_thread == VMThread::vm_thread()), "must have threads lock to call this");
1511 internal_do_task();
1512 _done = true;
1513 }
1514
1515 bool os::create_stack_guard_pages(char* addr, size_t bytes) {
1516 return os::pd_create_stack_guard_pages(addr, bytes);
1517 }
1518
1519 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint) {
1520 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1521 if (result != NULL) {
1522 MemTracker::record_virtual_memory_reserve((address)result, bytes, mtNone, CALLER_PC);
1523 }
1524
1525 return result;
1526 }
1527
1528 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint,
1529 MEMFLAGS flags) {
1530 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1531 if (result != NULL) {
1532 MemTracker::record_virtual_memory_reserve((address)result, bytes, mtNone, CALLER_PC);
1533 MemTracker::record_virtual_memory_type((address)result, flags);
1534 }
1535
1536 return result;
1537 }
1538
1539 char* os::attempt_reserve_memory_at(size_t bytes, char* addr) {
1540 char* result = pd_attempt_reserve_memory_at(bytes, addr);
1541 if (result != NULL) {
1542 MemTracker::record_virtual_memory_reserve((address)result, bytes, mtNone, CALLER_PC);
1543 }
1544 return result;
1545 }
1546
1547 void os::split_reserved_memory(char *base, size_t size,
1548 size_t split, bool realloc) {
1549 pd_split_reserved_memory(base, size, split, realloc);
1550 }
1551
1552 bool os::commit_memory(char* addr, size_t bytes, bool executable) {
1553 bool res = pd_commit_memory(addr, bytes, executable);
1554 if (res) {
1555 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1556 }
1557 return res;
1558 }
1559
1560 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint,
1561 bool executable) {
1562 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable);
1563 if (res) {
1564 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1565 }
1566 return res;
1567 }
1568
1569 void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable,
1570 const char* mesg) {
1571 pd_commit_memory_or_exit(addr, bytes, executable, mesg);
1572 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1573 }
1574
1575 void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint,
1576 bool executable, const char* mesg) {
1577 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg);
1578 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1579 }
1580
1581 bool os::uncommit_memory(char* addr, size_t bytes) {
1582 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_uncommit_tracker();
1583 bool res = pd_uncommit_memory(addr, bytes);
1584 if (res) {
1585 tkr.record((address)addr, bytes);
1586 } else {
1587 tkr.discard();
1588 }
1589 return res;
1590 }
1591
1592 bool os::release_memory(char* addr, size_t bytes) {
1593 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
1594 bool res = pd_release_memory(addr, bytes);
1595 if (res) {
1596 tkr.record((address)addr, bytes);
1597 } else {
1598 tkr.discard();
1599 }
1600 return res;
1601 }
1602
1603
1604 char* os::map_memory(int fd, const char* file_name, size_t file_offset,
1605 char *addr, size_t bytes, bool read_only,
1606 bool allow_exec) {
1607 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec);
1608 if (result != NULL) {
1609 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, mtNone, CALLER_PC);
1610 }
1611 return result;
1612 }
1613
1614 char* os::remap_memory(int fd, const char* file_name, size_t file_offset,
1615 char *addr, size_t bytes, bool read_only,
1616 bool allow_exec) {
1617 return pd_remap_memory(fd, file_name, file_offset, addr, bytes,
1618 read_only, allow_exec);
1619 }
1620
1621 bool os::unmap_memory(char *addr, size_t bytes) {
1622 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
1623 bool result = pd_unmap_memory(addr, bytes);
1624 if (result) {
1625 tkr.record((address)addr, bytes);
1626 } else {
1627 tkr.discard();
1628 }
1629 return result;
1630 }
1631
1632 void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) {
1633 pd_free_memory(addr, bytes, alignment_hint);
1634 }
1635
1636 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
1637 pd_realign_memory(addr, bytes, alignment_hint);
1638 }
1639
1640 #ifndef TARGET_OS_FAMILY_windows
1641 /* try to switch state from state "from" to state "to"
1642 * returns the state set after the method is complete
1643 */
1644 os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from,
1645 os::SuspendResume::State to)
1646 {
1647 os::SuspendResume::State result =
1648 (os::SuspendResume::State) Atomic::cmpxchg((jint) to, (jint *) &_state, (jint) from);
1649 if (result == from) {
1650 // success
1651 return to;
1652 }
1653 return result;
1654 }
1655 #endif