1 /*
2 * Copyright (c) 1997, 2013, 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 OSThread* os::_starting_thread = NULL;
69 address os::_polling_page = NULL;
70 volatile int32_t* os::_mem_serialize_page = NULL;
71 uintptr_t os::_serialize_page_mask = 0;
72 long os::_rand_seed = 1;
73 int os::_processor_count = 0;
74 size_t os::_page_sizes[os::page_sizes_max];
75
76 #ifndef PRODUCT
77 julong os::num_mallocs = 0; // # of calls to malloc/realloc
78 julong os::alloc_bytes = 0; // # of bytes allocated
79 julong os::num_frees = 0; // # of calls to free
80 julong os::free_bytes = 0; // # of bytes freed
81 #endif
82
83 static juint cur_malloc_words = 0; // current size for MallocMaxTestWords
84
85 void os_init_globals() {
86 // Called from init_globals().
87 // See Threads::create_vm() in thread.cpp, and init.cpp.
88 os::init_globals();
89 }
90
91 // Fill in buffer with current local time as an ISO-8601 string.
92 // E.g., yyyy-mm-ddThh:mm:ss-zzzz.
93 // Returns buffer, or NULL if it failed.
94 // This would mostly be a call to
95 // strftime(...., "%Y-%m-%d" "T" "%H:%M:%S" "%z", ....)
96 // except that on Windows the %z behaves badly, so we do it ourselves.
97 // Also, people wanted milliseconds on there,
98 // and strftime doesn't do milliseconds.
99 char* os::iso8601_time(char* buffer, size_t buffer_length) {
100 // Output will be of the form "YYYY-MM-DDThh:mm:ss.mmm+zzzz\0"
101 // 1 2
102 // 12345678901234567890123456789
103 static const char* iso8601_format =
104 "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d";
105 static const size_t needed_buffer = 29;
106
107 // Sanity check the arguments
108 if (buffer == NULL) {
109 assert(false, "NULL buffer");
110 return NULL;
111 }
112 if (buffer_length < needed_buffer) {
113 assert(false, "buffer_length too small");
114 return NULL;
115 }
116 // Get the current time
117 jlong milliseconds_since_19700101 = javaTimeMillis();
118 const int milliseconds_per_microsecond = 1000;
119 const time_t seconds_since_19700101 =
120 milliseconds_since_19700101 / milliseconds_per_microsecond;
121 const int milliseconds_after_second =
122 milliseconds_since_19700101 % milliseconds_per_microsecond;
123 // Convert the time value to a tm and timezone variable
124 struct tm time_struct;
125 if (localtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
126 assert(false, "Failed localtime_pd");
127 return NULL;
128 }
129 #if defined(_ALLBSD_SOURCE)
130 const time_t zone = (time_t) time_struct.tm_gmtoff;
131 #else
132 const time_t zone = timezone;
133 #endif
134
135 // If daylight savings time is in effect,
136 // we are 1 hour East of our time zone
137 const time_t seconds_per_minute = 60;
138 const time_t minutes_per_hour = 60;
139 const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour;
140 time_t UTC_to_local = zone;
141 if (time_struct.tm_isdst > 0) {
142 UTC_to_local = UTC_to_local - seconds_per_hour;
143 }
144 // Compute the time zone offset.
145 // localtime_pd() sets timezone to the difference (in seconds)
146 // between UTC and and local time.
147 // ISO 8601 says we need the difference between local time and UTC,
148 // we change the sign of the localtime_pd() result.
149 const time_t local_to_UTC = -(UTC_to_local);
150 // Then we have to figure out if if we are ahead (+) or behind (-) UTC.
151 char sign_local_to_UTC = '+';
152 time_t abs_local_to_UTC = local_to_UTC;
153 if (local_to_UTC < 0) {
154 sign_local_to_UTC = '-';
155 abs_local_to_UTC = -(abs_local_to_UTC);
156 }
157 // Convert time zone offset seconds to hours and minutes.
158 const time_t zone_hours = (abs_local_to_UTC / seconds_per_hour);
159 const time_t zone_min =
160 ((abs_local_to_UTC % seconds_per_hour) / seconds_per_minute);
161
162 // Print an ISO 8601 date and time stamp into the buffer
163 const int year = 1900 + time_struct.tm_year;
164 const int month = 1 + time_struct.tm_mon;
165 const int printed = jio_snprintf(buffer, buffer_length, iso8601_format,
166 year,
167 month,
168 time_struct.tm_mday,
169 time_struct.tm_hour,
170 time_struct.tm_min,
171 time_struct.tm_sec,
172 milliseconds_after_second,
173 sign_local_to_UTC,
174 zone_hours,
175 zone_min);
176 if (printed == 0) {
177 assert(false, "Failed jio_printf");
178 return NULL;
179 }
180 return buffer;
181 }
182
183 OSReturn os::set_priority(Thread* thread, ThreadPriority p) {
184 #ifdef ASSERT
185 if (!(!thread->is_Java_thread() ||
186 Thread::current() == thread ||
187 Threads_lock->owned_by_self()
188 || thread->is_Compiler_thread()
189 )) {
190 assert(false, "possibility of dangling Thread pointer");
191 }
192 #endif
193
194 if (p >= MinPriority && p <= MaxPriority) {
195 int priority = java_to_os_priority[p];
196 return set_native_priority(thread, priority);
197 } else {
198 assert(false, "Should not happen");
199 return OS_ERR;
200 }
201 }
202
203 // The mapping from OS priority back to Java priority may be inexact because
204 // Java priorities can map M:1 with native priorities. If you want the definite
205 // Java priority then use JavaThread::java_priority()
206 OSReturn os::get_priority(const Thread* const thread, ThreadPriority& priority) {
207 int p;
208 int os_prio;
209 OSReturn ret = get_native_priority(thread, &os_prio);
210 if (ret != OS_OK) return ret;
211
212 if (java_to_os_priority[MaxPriority] > java_to_os_priority[MinPriority]) {
213 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] > os_prio; p--) ;
214 } else {
215 // niceness values are in reverse order
216 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] < os_prio; p--) ;
217 }
218 priority = (ThreadPriority)p;
219 return OS_OK;
220 }
221
222
223 // --------------------- sun.misc.Signal (optional) ---------------------
224
225
226 // SIGBREAK is sent by the keyboard to query the VM state
227 #ifndef SIGBREAK
228 #define SIGBREAK SIGQUIT
229 #endif
230
231 // sigexitnum_pd is a platform-specific special signal used for terminating the Signal thread.
232
233
234 static void signal_thread_entry(JavaThread* thread, TRAPS) {
235 os::set_priority(thread, NearMaxPriority);
236 while (true) {
237 int sig;
238 {
239 // FIXME : Currently we have not decieded what should be the status
240 // for this java thread blocked here. Once we decide about
241 // that we should fix this.
242 sig = os::signal_wait();
243 }
244 if (sig == os::sigexitnum_pd()) {
245 // Terminate the signal thread
246 return;
247 }
248
249 switch (sig) {
250 case SIGBREAK: {
251 // Check if the signal is a trigger to start the Attach Listener - in that
252 // case don't print stack traces.
253 if (!DisableAttachMechanism && AttachListener::is_init_trigger()) {
254 continue;
255 }
256 // Print stack traces
257 // Any SIGBREAK operations added here should make sure to flush
258 // the output stream (e.g. tty->flush()) after output. See 4803766.
259 // Each module also prints an extra carriage return after its output.
260 VM_PrintThreads op;
261 VMThread::execute(&op);
262 VM_PrintJNI jni_op;
263 VMThread::execute(&jni_op);
264 VM_FindDeadlocks op1(tty);
265 VMThread::execute(&op1);
266 Universe::print_heap_at_SIGBREAK();
267 if (PrintClassHistogram) {
268 VM_GC_HeapInspection op1(gclog_or_tty, true /* force full GC before heap inspection */);
269 VMThread::execute(&op1);
270 }
271 if (JvmtiExport::should_post_data_dump()) {
272 JvmtiExport::post_data_dump();
273 }
274 break;
275 }
276 default: {
277 // Dispatch the signal to java
278 HandleMark hm(THREAD);
279 Klass* k = SystemDictionary::resolve_or_null(vmSymbols::sun_misc_Signal(), THREAD);
280 KlassHandle klass (THREAD, k);
281 if (klass.not_null()) {
282 JavaValue result(T_VOID);
283 JavaCallArguments args;
284 args.push_int(sig);
285 JavaCalls::call_static(
286 &result,
287 klass,
288 vmSymbols::dispatch_name(),
289 vmSymbols::int_void_signature(),
290 &args,
291 THREAD
292 );
293 }
294 if (HAS_PENDING_EXCEPTION) {
295 // tty is initialized early so we don't expect it to be null, but
296 // if it is we can't risk doing an initialization that might
297 // trigger additional out-of-memory conditions
298 if (tty != NULL) {
299 char klass_name[256];
300 char tmp_sig_name[16];
301 const char* sig_name = "UNKNOWN";
302 InstanceKlass::cast(PENDING_EXCEPTION->klass())->
303 name()->as_klass_external_name(klass_name, 256);
304 if (os::exception_name(sig, tmp_sig_name, 16) != NULL)
305 sig_name = tmp_sig_name;
306 warning("Exception %s occurred dispatching signal %s to handler"
307 "- the VM may need to be forcibly terminated",
308 klass_name, sig_name );
309 }
310 CLEAR_PENDING_EXCEPTION;
311 }
312 }
313 }
314 }
315 }
316
317
318 void os::signal_init() {
319 if (!ReduceSignalUsage) {
320 // Setup JavaThread for processing signals
321 EXCEPTION_MARK;
322 Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(), true, CHECK);
323 instanceKlassHandle klass (THREAD, k);
324 instanceHandle thread_oop = klass->allocate_instance_handle(CHECK);
325
326 const char thread_name[] = "Signal Dispatcher";
327 Handle string = java_lang_String::create_from_str(thread_name, CHECK);
328
329 // Initialize thread_oop to put it into the system threadGroup
330 Handle thread_group (THREAD, Universe::system_thread_group());
331 JavaValue result(T_VOID);
332 JavaCalls::call_special(&result, thread_oop,
333 klass,
334 vmSymbols::object_initializer_name(),
335 vmSymbols::threadgroup_string_void_signature(),
336 thread_group,
337 string,
338 CHECK);
339
340 KlassHandle group(THREAD, SystemDictionary::ThreadGroup_klass());
341 JavaCalls::call_special(&result,
342 thread_group,
343 group,
344 vmSymbols::add_method_name(),
345 vmSymbols::thread_void_signature(),
346 thread_oop, // ARG 1
347 CHECK);
348
349 os::signal_init_pd();
350
351 { MutexLocker mu(Threads_lock);
352 JavaThread* signal_thread = new JavaThread(&signal_thread_entry);
353
354 // At this point it may be possible that no osthread was created for the
355 // JavaThread due to lack of memory. We would have to throw an exception
356 // in that case. However, since this must work and we do not allow
357 // exceptions anyway, check and abort if this fails.
358 if (signal_thread == NULL || signal_thread->osthread() == NULL) {
359 vm_exit_during_initialization("java.lang.OutOfMemoryError",
360 "unable to create new native thread");
361 }
362
363 java_lang_Thread::set_thread(thread_oop(), signal_thread);
364 java_lang_Thread::set_priority(thread_oop(), NearMaxPriority);
365 java_lang_Thread::set_daemon(thread_oop());
366
367 signal_thread->set_threadObj(thread_oop());
368 Threads::add(signal_thread);
369 Thread::start(signal_thread);
370 }
371 // Handle ^BREAK
372 os::signal(SIGBREAK, os::user_handler());
373 }
374 }
375
376
377 void os::terminate_signal_thread() {
378 if (!ReduceSignalUsage)
379 signal_notify(sigexitnum_pd());
380 }
381
382
383 // --------------------- loading libraries ---------------------
384
385 typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *);
386 extern struct JavaVM_ main_vm;
387
388 static void* _native_java_library = NULL;
389
390 void* os::native_java_library() {
391 if (_native_java_library == NULL) {
392 char buffer[JVM_MAXPATHLEN];
393 char ebuf[1024];
394
395 // Try to load verify dll first. In 1.3 java dll depends on it and is not
396 // always able to find it when the loading executable is outside the JDK.
397 // In order to keep working with 1.2 we ignore any loading errors.
398 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
399 "verify")) {
400 dll_load(buffer, ebuf, sizeof(ebuf));
401 }
402
403 // Load java dll
404 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
405 "java")) {
406 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf));
407 }
408 if (_native_java_library == NULL) {
409 vm_exit_during_initialization("Unable to load native library", ebuf);
410 }
411
412 #if defined(__OpenBSD__)
413 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so
414 // ignore errors
415 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
416 "net")) {
417 dll_load(buffer, ebuf, sizeof(ebuf));
418 }
419 #endif
420 }
421 static jboolean onLoaded = JNI_FALSE;
422 if (onLoaded) {
423 // We may have to wait to fire OnLoad until TLS is initialized.
424 if (ThreadLocalStorage::is_initialized()) {
425 // The JNI_OnLoad handling is normally done by method load in
426 // java.lang.ClassLoader$NativeLibrary, but the VM loads the base library
427 // explicitly so we have to check for JNI_OnLoad as well
428 const char *onLoadSymbols[] = JNI_ONLOAD_SYMBOLS;
429 JNI_OnLoad_t JNI_OnLoad = CAST_TO_FN_PTR(
430 JNI_OnLoad_t, dll_lookup(_native_java_library, onLoadSymbols[0]));
431 if (JNI_OnLoad != NULL) {
432 JavaThread* thread = JavaThread::current();
433 ThreadToNativeFromVM ttn(thread);
434 HandleMark hm(thread);
435 jint ver = (*JNI_OnLoad)(&main_vm, NULL);
436 onLoaded = JNI_TRUE;
437 if (!Threads::is_supported_jni_version_including_1_1(ver)) {
438 vm_exit_during_initialization("Unsupported JNI version");
439 }
440 }
441 }
442 }
443 return _native_java_library;
444 }
445
446 /*
447 * Support for finding Agent_On(Un)Load/Attach<_lib_name> if it exists.
448 * If check_lib == true then we are looking for an
449 * Agent_OnLoad_lib_name or Agent_OnAttach_lib_name function to determine if
450 * this library is statically linked into the image.
451 * If check_lib == false then we will look for the appropriate symbol in the
452 * executable if agent_lib->is_static_lib() == true or in the shared library
453 * referenced by 'handle'.
454 */
455 void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib,
456 const char *syms[], size_t syms_len) {
457 const char *lib_name;
458 void *handle = agent_lib->os_lib();
459 void *entryName = NULL;
460 char *agent_function_name;
461 size_t i;
462
463 // If checking then use the agent name otherwise test is_static_lib() to
464 // see how to process this lookup
465 lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL);
466 for (i = 0; i < syms_len; i++) {
467 agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path());
468 if (agent_function_name == NULL) {
469 break;
470 }
471 entryName = dll_lookup(handle, agent_function_name);
472 FREE_C_HEAP_ARRAY(char, agent_function_name, mtThread);
473 if (entryName != NULL) {
474 break;
475 }
476 }
477 return entryName;
478 }
479
480 // See if the passed in agent is statically linked into the VM image.
481 bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
482 size_t syms_len) {
483 void *ret;
484 void *proc_handle;
485 void *save_handle;
486
487 if (agent_lib->name() == NULL) {
488 return false;
489 }
490 proc_handle = get_default_process_handle();
491 // Check for Agent_OnLoad/Attach_lib_name function
492 save_handle = agent_lib->os_lib();
493 // We want to look in this process' symbol table.
494 agent_lib->set_os_lib(proc_handle);
495 ret = find_agent_function(agent_lib, true, syms, syms_len);
496 agent_lib->set_os_lib(save_handle);
497 if (ret != NULL) {
498 // Found an entry point like Agent_OnLoad_lib_name so we have a static agent
499 agent_lib->set_os_lib(proc_handle);
500 agent_lib->set_valid();
501 agent_lib->set_static_lib(true);
502 return true;
503 }
504 return false;
505 }
506
507 // --------------------- heap allocation utilities ---------------------
508
509 char *os::strdup(const char *str, MEMFLAGS flags) {
510 size_t size = strlen(str);
511 char *dup_str = (char *)malloc(size + 1, flags);
512 if (dup_str == NULL) return NULL;
513 strcpy(dup_str, str);
514 return dup_str;
515 }
516
517
518
519 #ifdef ASSERT
520 #define space_before (MallocCushion + sizeof(double))
521 #define space_after MallocCushion
522 #define size_addr_from_base(p) (size_t*)(p + space_before - sizeof(size_t))
523 #define size_addr_from_obj(p) ((size_t*)p - 1)
524 // MallocCushion: size of extra cushion allocated around objects with +UseMallocOnly
525 // NB: cannot be debug variable, because these aren't set from the command line until
526 // *after* the first few allocs already happened
527 #define MallocCushion 16
528 #else
529 #define space_before 0
530 #define space_after 0
531 #define size_addr_from_base(p) should not use w/o ASSERT
532 #define size_addr_from_obj(p) should not use w/o ASSERT
533 #define MallocCushion 0
534 #endif
535 #define paranoid 0 /* only set to 1 if you suspect checking code has bug */
536
537 #ifdef ASSERT
538 inline size_t get_size(void* obj) {
539 size_t size = *size_addr_from_obj(obj);
540 if (size < 0) {
541 fatal(err_msg("free: size field of object #" PTR_FORMAT " was overwritten ("
542 SIZE_FORMAT ")", obj, size));
543 }
544 return size;
545 }
546
547 u_char* find_cushion_backwards(u_char* start) {
548 u_char* p = start;
549 while (p[ 0] != badResourceValue || p[-1] != badResourceValue ||
550 p[-2] != badResourceValue || p[-3] != badResourceValue) p--;
551 // ok, we have four consecutive marker bytes; find start
552 u_char* q = p - 4;
553 while (*q == badResourceValue) q--;
554 return q + 1;
555 }
556
557 u_char* find_cushion_forwards(u_char* start) {
558 u_char* p = start;
559 while (p[0] != badResourceValue || p[1] != badResourceValue ||
560 p[2] != badResourceValue || p[3] != badResourceValue) p++;
561 // ok, we have four consecutive marker bytes; find end of cushion
562 u_char* q = p + 4;
563 while (*q == badResourceValue) q++;
564 return q - MallocCushion;
565 }
566
567 void print_neighbor_blocks(void* ptr) {
568 // find block allocated before ptr (not entirely crash-proof)
569 if (MallocCushion < 4) {
570 tty->print_cr("### cannot find previous block (MallocCushion < 4)");
571 return;
572 }
573 u_char* start_of_this_block = (u_char*)ptr - space_before;
574 u_char* end_of_prev_block_data = start_of_this_block - space_after -1;
575 // look for cushion in front of prev. block
576 u_char* start_of_prev_block = find_cushion_backwards(end_of_prev_block_data);
577 ptrdiff_t size = *size_addr_from_base(start_of_prev_block);
578 u_char* obj = start_of_prev_block + space_before;
579 if (size <= 0 ) {
580 // start is bad; mayhave been confused by OS data inbetween objects
581 // search one more backwards
582 start_of_prev_block = find_cushion_backwards(start_of_prev_block);
583 size = *size_addr_from_base(start_of_prev_block);
584 obj = start_of_prev_block + space_before;
585 }
586
587 if (start_of_prev_block + space_before + size + space_after == start_of_this_block) {
588 tty->print_cr("### previous object: " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", obj, size);
589 } else {
590 tty->print_cr("### previous object (not sure if correct): " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", obj, size);
591 }
592
593 // now find successor block
594 u_char* start_of_next_block = (u_char*)ptr + *size_addr_from_obj(ptr) + space_after;
595 start_of_next_block = find_cushion_forwards(start_of_next_block);
596 u_char* next_obj = start_of_next_block + space_before;
597 ptrdiff_t next_size = *size_addr_from_base(start_of_next_block);
598 if (start_of_next_block[0] == badResourceValue &&
599 start_of_next_block[1] == badResourceValue &&
600 start_of_next_block[2] == badResourceValue &&
601 start_of_next_block[3] == badResourceValue) {
602 tty->print_cr("### next object: " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", next_obj, next_size);
603 } else {
604 tty->print_cr("### next object (not sure if correct): " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", next_obj, next_size);
605 }
606 }
607
608
609 void report_heap_error(void* memblock, void* bad, const char* where) {
610 tty->print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees);
611 tty->print_cr("## memory stomp: byte at " PTR_FORMAT " %s object " PTR_FORMAT, bad, where, memblock);
612 print_neighbor_blocks(memblock);
613 fatal("memory stomping error");
614 }
615
616 void verify_block(void* memblock) {
617 size_t size = get_size(memblock);
618 if (MallocCushion) {
619 u_char* ptr = (u_char*)memblock - space_before;
620 for (int i = 0; i < MallocCushion; i++) {
621 if (ptr[i] != badResourceValue) {
622 report_heap_error(memblock, ptr+i, "in front of");
623 }
624 }
625 u_char* end = (u_char*)memblock + size + space_after;
626 for (int j = -MallocCushion; j < 0; j++) {
627 if (end[j] != badResourceValue) {
628 report_heap_error(memblock, end+j, "after");
629 }
630 }
631 }
632 }
633 #endif
634
635 //
636 // This function supports testing of the malloc out of memory
637 // condition without really running the system out of memory.
638 //
639 static u_char* testMalloc(size_t alloc_size) {
640 assert(MallocMaxTestWords > 0, "sanity check");
641
642 if ((cur_malloc_words + (alloc_size / BytesPerWord)) > MallocMaxTestWords) {
643 return NULL;
644 }
645
646 u_char* ptr = (u_char*)::malloc(alloc_size);
647
648 if (ptr != NULL) {
649 Atomic::add(((jint) (alloc_size / BytesPerWord)),
650 (volatile jint *) &cur_malloc_words);
651 }
652 return ptr;
653 }
654
655 void* os::malloc(size_t size, MEMFLAGS memflags, address caller) {
656 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
657 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
658
659 #ifdef ASSERT
660 // checking for the WatcherThread and crash_protection first
661 // since os::malloc can be called when the libjvm.{dll,so} is
662 // first loaded and we don't have a thread yet.
663 // try to find the thread after we see that the watcher thread
664 // exists and has crash protection.
665 WatcherThread *wt = WatcherThread::watcher_thread();
666 if (wt != NULL && wt->has_crash_protection()) {
667 Thread* thread = ThreadLocalStorage::get_thread_slow();
668 if (thread == wt) {
669 assert(!wt->has_crash_protection(),
670 "Can't malloc with crash protection from WatcherThread");
671 }
672 }
673 #endif
674
675 if (size == 0) {
676 // return a valid pointer if size is zero
677 // if NULL is returned the calling functions assume out of memory.
678 size = 1;
679 }
680
681 const size_t alloc_size = size + space_before + space_after;
682
683 if (size > alloc_size) { // Check for rollover.
684 return NULL;
685 }
686
687 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
688
689 u_char* ptr;
690
691 if (MallocMaxTestWords > 0) {
692 ptr = testMalloc(alloc_size);
693 } else {
694 ptr = (u_char*)::malloc(alloc_size);
695 }
696
697 #ifdef ASSERT
698 if (ptr == NULL) return NULL;
699 if (MallocCushion) {
700 for (u_char* p = ptr; p < ptr + MallocCushion; p++) *p = (u_char)badResourceValue;
701 u_char* end = ptr + space_before + size;
702 for (u_char* pq = ptr+MallocCushion; pq < end; pq++) *pq = (u_char)uninitBlockPad;
703 for (u_char* q = end; q < end + MallocCushion; q++) *q = (u_char)badResourceValue;
704 }
705 // put size just before data
706 *size_addr_from_base(ptr) = size;
707 #endif
708 u_char* memblock = ptr + space_before;
709 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
710 tty->print_cr("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, memblock);
711 breakpoint();
712 }
713 debug_only(if (paranoid) verify_block(memblock));
714 if (PrintMalloc && tty != NULL) tty->print_cr("os::malloc " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, memblock);
715
716 // we do not track MallocCushion memory
717 MemTracker::record_malloc((address)memblock, size, memflags, caller == 0 ? CALLER_PC : caller);
718
719 return memblock;
720 }
721
722
723 void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, address caller) {
724 #ifndef ASSERT
725 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
726 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
727 MemTracker::Tracker tkr = MemTracker::get_realloc_tracker();
728 void* ptr = ::realloc(memblock, size);
729 if (ptr != NULL) {
730 tkr.record((address)memblock, (address)ptr, size, memflags,
731 caller == 0 ? CALLER_PC : caller);
732 } else {
733 tkr.discard();
734 }
735 return ptr;
736 #else
737 if (memblock == NULL) {
738 return malloc(size, memflags, (caller == 0 ? CALLER_PC : caller));
739 }
740 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
741 tty->print_cr("os::realloc caught " PTR_FORMAT, memblock);
742 breakpoint();
743 }
744 verify_block(memblock);
745 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
746 if (size == 0) return NULL;
747 // always move the block
748 void* ptr = malloc(size, memflags, caller == 0 ? CALLER_PC : caller);
749 if (PrintMalloc) tty->print_cr("os::remalloc " SIZE_FORMAT " bytes, " PTR_FORMAT " --> " PTR_FORMAT, size, memblock, ptr);
750 // Copy to new memory if malloc didn't fail
751 if ( ptr != NULL ) {
752 memcpy(ptr, memblock, MIN2(size, get_size(memblock)));
753 if (paranoid) verify_block(ptr);
754 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) {
755 tty->print_cr("os::realloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr);
756 breakpoint();
757 }
758 free(memblock);
759 }
760 return ptr;
761 #endif
762 }
763
764
765 void os::free(void *memblock, MEMFLAGS memflags) {
766 NOT_PRODUCT(inc_stat_counter(&num_frees, 1));
767 #ifdef ASSERT
768 if (memblock == NULL) return;
769 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
770 if (tty != NULL) tty->print_cr("os::free caught " PTR_FORMAT, memblock);
771 breakpoint();
772 }
773 verify_block(memblock);
774 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
775 // Added by detlefs.
776 if (MallocCushion) {
777 u_char* ptr = (u_char*)memblock - space_before;
778 for (u_char* p = ptr; p < ptr + MallocCushion; p++) {
779 guarantee(*p == badResourceValue,
780 "Thing freed should be malloc result.");
781 *p = (u_char)freeBlockPad;
782 }
783 size_t size = get_size(memblock);
784 inc_stat_counter(&free_bytes, size);
785 u_char* end = ptr + space_before + size;
786 for (u_char* q = end; q < end + MallocCushion; q++) {
787 guarantee(*q == badResourceValue,
788 "Thing freed should be malloc result.");
789 *q = (u_char)freeBlockPad;
790 }
791 if (PrintMalloc && tty != NULL)
792 fprintf(stderr, "os::free " SIZE_FORMAT " bytes --> " PTR_FORMAT "\n", size, (uintptr_t)memblock);
793 } else if (PrintMalloc && tty != NULL) {
794 // tty->print_cr("os::free %p", memblock);
795 fprintf(stderr, "os::free " PTR_FORMAT "\n", (uintptr_t)memblock);
796 }
797 #endif
798 MemTracker::record_free((address)memblock, memflags);
799
800 ::free((char*)memblock - space_before);
801 }
802
803 void os::init_random(long initval) {
804 _rand_seed = initval;
805 }
806
807
808 long os::random() {
809 /* standard, well-known linear congruential random generator with
810 * next_rand = (16807*seed) mod (2**31-1)
811 * see
812 * (1) "Random Number Generators: Good Ones Are Hard to Find",
813 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988),
814 * (2) "Two Fast Implementations of the 'Minimal Standard' Random
815 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88.
816 */
817 const long a = 16807;
818 const unsigned long m = 2147483647;
819 const long q = m / a; assert(q == 127773, "weird math");
820 const long r = m % a; assert(r == 2836, "weird math");
821
822 // compute az=2^31p+q
823 unsigned long lo = a * (long)(_rand_seed & 0xFFFF);
824 unsigned long hi = a * (long)((unsigned long)_rand_seed >> 16);
825 lo += (hi & 0x7FFF) << 16;
826
827 // if q overflowed, ignore the overflow and increment q
828 if (lo > m) {
829 lo &= m;
830 ++lo;
831 }
832 lo += hi >> 15;
833
834 // if (p+q) overflowed, ignore the overflow and increment (p+q)
835 if (lo > m) {
836 lo &= m;
837 ++lo;
838 }
839 return (_rand_seed = lo);
840 }
841
842 // The INITIALIZED state is distinguished from the SUSPENDED state because the
843 // conditions in which a thread is first started are different from those in which
844 // a suspension is resumed. These differences make it hard for us to apply the
845 // tougher checks when starting threads that we want to do when resuming them.
846 // However, when start_thread is called as a result of Thread.start, on a Java
847 // thread, the operation is synchronized on the Java Thread object. So there
848 // cannot be a race to start the thread and hence for the thread to exit while
849 // we are working on it. Non-Java threads that start Java threads either have
850 // to do so in a context in which races are impossible, or should do appropriate
851 // locking.
852
853 void os::start_thread(Thread* thread) {
854 // guard suspend/resume
855 MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag);
856 OSThread* osthread = thread->osthread();
857 osthread->set_state(RUNNABLE);
858 pd_start_thread(thread);
859 }
860
861 //---------------------------------------------------------------------------
862 // Helper functions for fatal error handler
863
864 void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) {
865 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking");
866
867 int cols = 0;
868 int cols_per_line = 0;
869 switch (unitsize) {
870 case 1: cols_per_line = 16; break;
871 case 2: cols_per_line = 8; break;
872 case 4: cols_per_line = 4; break;
873 case 8: cols_per_line = 2; break;
874 default: return;
875 }
876
877 address p = start;
878 st->print(PTR_FORMAT ": ", start);
879 while (p < end) {
880 switch (unitsize) {
881 case 1: st->print("%02x", *(u1*)p); break;
882 case 2: st->print("%04x", *(u2*)p); break;
883 case 4: st->print("%08x", *(u4*)p); break;
884 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break;
885 }
886 p += unitsize;
887 cols++;
888 if (cols >= cols_per_line && p < end) {
889 cols = 0;
890 st->cr();
891 st->print(PTR_FORMAT ": ", p);
892 } else {
893 st->print(" ");
894 }
895 }
896 st->cr();
897 }
898
899 void os::print_environment_variables(outputStream* st, const char** env_list,
900 char* buffer, int len) {
901 if (env_list) {
902 st->print_cr("Environment Variables:");
903
904 for (int i = 0; env_list[i] != NULL; i++) {
905 if (getenv(env_list[i], buffer, len)) {
906 st->print(env_list[i]);
907 st->print("=");
908 st->print_cr(buffer);
909 }
910 }
911 }
912 }
913
914 void os::print_cpu_info(outputStream* st) {
915 // cpu
916 st->print("CPU:");
917 st->print("total %d", os::processor_count());
918 // It's not safe to query number of active processors after crash
919 // st->print("(active %d)", os::active_processor_count());
920 st->print(" %s", VM_Version::cpu_features());
921 st->cr();
922 pd_print_cpu_info(st);
923 }
924
925 void os::print_date_and_time(outputStream *st) {
926 time_t tloc;
927 (void)time(&tloc);
928 st->print("time: %s", ctime(&tloc)); // ctime adds newline.
929
930 double t = os::elapsedTime();
931 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in
932 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int
933 // before printf. We lost some precision, but who cares?
934 st->print_cr("elapsed time: %d seconds", (int)t);
935 }
936
937 // moved from debug.cpp (used to be find()) but still called from there
938 // The verbose parameter is only set by the debug code in one case
939 void os::print_location(outputStream* st, intptr_t x, bool verbose) {
940 address addr = (address)x;
941 CodeBlob* b = CodeCache::find_blob_unsafe(addr);
942 if (b != NULL) {
943 if (b->is_buffer_blob()) {
944 // the interpreter is generated into a buffer blob
945 InterpreterCodelet* i = Interpreter::codelet_containing(addr);
946 if (i != NULL) {
947 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an Interpreter codelet", addr, (int)(addr - i->code_begin()));
948 i->print_on(st);
949 return;
950 }
951 if (Interpreter::contains(addr)) {
952 st->print_cr(INTPTR_FORMAT " is pointing into interpreter code"
953 " (not bytecode specific)", addr);
954 return;
955 }
956 //
957 if (AdapterHandlerLibrary::contains(b)) {
958 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an AdapterHandler", addr, (int)(addr - b->code_begin()));
959 AdapterHandlerLibrary::print_handler_on(st, b);
960 }
961 // the stubroutines are generated into a buffer blob
962 StubCodeDesc* d = StubCodeDesc::desc_for(addr);
963 if (d != NULL) {
964 st->print_cr(INTPTR_FORMAT " is at begin+%d in a stub", addr, (int)(addr - d->begin()));
965 d->print_on(st);
966 st->cr();
967 return;
968 }
969 if (StubRoutines::contains(addr)) {
970 st->print_cr(INTPTR_FORMAT " is pointing to an (unnamed) "
971 "stub routine", addr);
972 return;
973 }
974 // the InlineCacheBuffer is using stubs generated into a buffer blob
975 if (InlineCacheBuffer::contains(addr)) {
976 st->print_cr(INTPTR_FORMAT " is pointing into InlineCacheBuffer", addr);
977 return;
978 }
979 VtableStub* v = VtableStubs::stub_containing(addr);
980 if (v != NULL) {
981 st->print_cr(INTPTR_FORMAT " is at entry_point+%d in a vtable stub", addr, (int)(addr - v->entry_point()));
982 v->print_on(st);
983 st->cr();
984 return;
985 }
986 }
987 nmethod* nm = b->as_nmethod_or_null();
988 if (nm != NULL) {
989 ResourceMark rm;
990 st->print(INTPTR_FORMAT " is at entry_point+%d in (nmethod*)" INTPTR_FORMAT,
991 addr, (int)(addr - nm->entry_point()), nm);
992 if (verbose) {
993 st->print(" for ");
994 nm->method()->print_value_on(st);
995 }
996 st->cr();
997 nm->print_nmethod(verbose);
998 return;
999 }
1000 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in ", addr, (int)(addr - b->code_begin()));
1001 b->print_on(st);
1002 return;
1003 }
1004
1005 if (Universe::heap()->is_in(addr)) {
1006 HeapWord* p = Universe::heap()->block_start(addr);
1007 bool print = false;
1008 // If we couldn't find it it just may mean that heap wasn't parseable
1009 // See if we were just given an oop directly
1010 if (p != NULL && Universe::heap()->block_is_obj(p)) {
1011 print = true;
1012 } else if (p == NULL && ((oopDesc*)addr)->is_oop()) {
1013 p = (HeapWord*) addr;
1014 print = true;
1015 }
1016 if (print) {
1017 if (p == (HeapWord*) addr) {
1018 st->print_cr(INTPTR_FORMAT " is an oop", addr);
1019 } else {
1020 st->print_cr(INTPTR_FORMAT " is pointing into object: " INTPTR_FORMAT, addr, p);
1021 }
1022 oop(p)->print_on(st);
1023 return;
1024 }
1025 } else {
1026 if (Universe::heap()->is_in_reserved(addr)) {
1027 st->print_cr(INTPTR_FORMAT " is an unallocated location "
1028 "in the heap", addr);
1029 return;
1030 }
1031 }
1032 if (JNIHandles::is_global_handle((jobject) addr)) {
1033 st->print_cr(INTPTR_FORMAT " is a global jni handle", addr);
1034 return;
1035 }
1036 if (JNIHandles::is_weak_global_handle((jobject) addr)) {
1037 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", addr);
1038 return;
1039 }
1040 #ifndef PRODUCT
1041 // we don't keep the block list in product mode
1042 if (JNIHandleBlock::any_contains((jobject) addr)) {
1043 st->print_cr(INTPTR_FORMAT " is a local jni handle", addr);
1044 return;
1045 }
1046 #endif
1047
1048 for(JavaThread *thread = Threads::first(); thread; thread = thread->next()) {
1049 // Check for privilege stack
1050 if (thread->privileged_stack_top() != NULL &&
1051 thread->privileged_stack_top()->contains(addr)) {
1052 st->print_cr(INTPTR_FORMAT " is pointing into the privilege stack "
1053 "for thread: " INTPTR_FORMAT, addr, thread);
1054 if (verbose) thread->print_on(st);
1055 return;
1056 }
1057 // If the addr is a java thread print information about that.
1058 if (addr == (address)thread) {
1059 if (verbose) {
1060 thread->print_on(st);
1061 } else {
1062 st->print_cr(INTPTR_FORMAT " is a thread", addr);
1063 }
1064 return;
1065 }
1066 // If the addr is in the stack region for this thread then report that
1067 // and print thread info
1068 if (thread->stack_base() >= addr &&
1069 addr > (thread->stack_base() - thread->stack_size())) {
1070 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: "
1071 INTPTR_FORMAT, addr, thread);
1072 if (verbose) thread->print_on(st);
1073 return;
1074 }
1075
1076 }
1077
1078 #ifndef PRODUCT
1079 // Check if in metaspace.
1080 if (ClassLoaderDataGraph::contains((address)addr)) {
1081 // Use addr->print() from the debugger instead (not here)
1082 st->print_cr(INTPTR_FORMAT
1083 " is pointing into metadata", addr);
1084 return;
1085 }
1086 #endif
1087
1088 // Try an OS specific find
1089 if (os::find(addr, st)) {
1090 return;
1091 }
1092
1093 st->print_cr(INTPTR_FORMAT " is an unknown value", addr);
1094 }
1095
1096 // Looks like all platforms except IA64 can use the same function to check
1097 // if C stack is walkable beyond current frame. The check for fp() is not
1098 // necessary on Sparc, but it's harmless.
1099 bool os::is_first_C_frame(frame* fr) {
1100 #if defined(IA64) && !defined(_WIN32)
1101 // On IA64 we have to check if the callers bsp is still valid
1102 // (i.e. within the register stack bounds).
1103 // Notice: this only works for threads created by the VM and only if
1104 // we walk the current stack!!! If we want to be able to walk
1105 // arbitrary other threads, we'll have to somehow store the thread
1106 // object in the frame.
1107 Thread *thread = Thread::current();
1108 if ((address)fr->fp() <=
1109 thread->register_stack_base() HPUX_ONLY(+ 0x0) LINUX_ONLY(+ 0x50)) {
1110 // This check is a little hacky, because on Linux the first C
1111 // frame's ('start_thread') register stack frame starts at
1112 // "register_stack_base + 0x48" while on HPUX, the first C frame's
1113 // ('__pthread_bound_body') register stack frame seems to really
1114 // start at "register_stack_base".
1115 return true;
1116 } else {
1117 return false;
1118 }
1119 #elif defined(IA64) && defined(_WIN32)
1120 return true;
1121 #else
1122 // Load up sp, fp, sender sp and sender fp, check for reasonable values.
1123 // Check usp first, because if that's bad the other accessors may fault
1124 // on some architectures. Ditto ufp second, etc.
1125 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1);
1126 // sp on amd can be 32 bit aligned.
1127 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1);
1128
1129 uintptr_t usp = (uintptr_t)fr->sp();
1130 if ((usp & sp_align_mask) != 0) return true;
1131
1132 uintptr_t ufp = (uintptr_t)fr->fp();
1133 if ((ufp & fp_align_mask) != 0) return true;
1134
1135 uintptr_t old_sp = (uintptr_t)fr->sender_sp();
1136 if ((old_sp & sp_align_mask) != 0) return true;
1137 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true;
1138
1139 uintptr_t old_fp = (uintptr_t)fr->link();
1140 if ((old_fp & fp_align_mask) != 0) return true;
1141 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true;
1142
1143 // stack grows downwards; if old_fp is below current fp or if the stack
1144 // frame is too large, either the stack is corrupted or fp is not saved
1145 // on stack (i.e. on x86, ebp may be used as general register). The stack
1146 // is not walkable beyond current frame.
1147 if (old_fp < ufp) return true;
1148 if (old_fp - ufp > 64 * K) return true;
1149
1150 return false;
1151 #endif
1152 }
1153
1154 #ifdef ASSERT
1155 extern "C" void test_random() {
1156 const double m = 2147483647;
1157 double mean = 0.0, variance = 0.0, t;
1158 long reps = 10000;
1159 unsigned long seed = 1;
1160
1161 tty->print_cr("seed %ld for %ld repeats...", seed, reps);
1162 os::init_random(seed);
1163 long num;
1164 for (int k = 0; k < reps; k++) {
1165 num = os::random();
1166 double u = (double)num / m;
1167 assert(u >= 0.0 && u <= 1.0, "bad random number!");
1168
1169 // calculate mean and variance of the random sequence
1170 mean += u;
1171 variance += (u*u);
1172 }
1173 mean /= reps;
1174 variance /= (reps - 1);
1175
1176 assert(num == 1043618065, "bad seed");
1177 tty->print_cr("mean of the 1st 10000 numbers: %f", mean);
1178 tty->print_cr("variance of the 1st 10000 numbers: %f", variance);
1179 const double eps = 0.0001;
1180 t = fabsd(mean - 0.5018);
1181 assert(t < eps, "bad mean");
1182 t = (variance - 0.3355) < 0.0 ? -(variance - 0.3355) : variance - 0.3355;
1183 assert(t < eps, "bad variance");
1184 }
1185 #endif
1186
1187
1188 // Set up the boot classpath.
1189
1190 char* os::format_boot_path(const char* format_string,
1191 const char* home,
1192 int home_len,
1193 char fileSep,
1194 char pathSep) {
1195 assert((fileSep == '/' && pathSep == ':') ||
1196 (fileSep == '\\' && pathSep == ';'), "unexpected seperator chars");
1197
1198 // Scan the format string to determine the length of the actual
1199 // boot classpath, and handle platform dependencies as well.
1200 int formatted_path_len = 0;
1201 const char* p;
1202 for (p = format_string; *p != 0; ++p) {
1203 if (*p == '%') formatted_path_len += home_len - 1;
1204 ++formatted_path_len;
1205 }
1206
1207 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal);
1208 if (formatted_path == NULL) {
1209 return NULL;
1210 }
1211
1212 // Create boot classpath from format, substituting separator chars and
1213 // java home directory.
1214 char* q = formatted_path;
1215 for (p = format_string; *p != 0; ++p) {
1216 switch (*p) {
1217 case '%':
1218 strcpy(q, home);
1219 q += home_len;
1220 break;
1221 case '/':
1222 *q++ = fileSep;
1223 break;
1224 case ':':
1225 *q++ = pathSep;
1226 break;
1227 default:
1228 *q++ = *p;
1229 }
1230 }
1231 *q = '\0';
1232
1233 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched");
1234 return formatted_path;
1235 }
1236
1237
1238 bool os::set_boot_path(char fileSep, char pathSep) {
1239 const char* home = Arguments::get_java_home();
1240 int home_len = (int)strlen(home);
1241
1242 static const char* meta_index_dir_format = "%/lib/";
1243 static const char* meta_index_format = "%/lib/meta-index";
1244 char* meta_index = format_boot_path(meta_index_format, home, home_len, fileSep, pathSep);
1245 if (meta_index == NULL) return false;
1246 char* meta_index_dir = format_boot_path(meta_index_dir_format, home, home_len, fileSep, pathSep);
1247 if (meta_index_dir == NULL) return false;
1248 Arguments::set_meta_index_path(meta_index, meta_index_dir);
1249
1250 // Any modification to the JAR-file list, for the boot classpath must be
1251 // aligned with install/install/make/common/Pack.gmk. Note: boot class
1252 // path class JARs, are stripped for StackMapTable to reduce download size.
1253 static const char classpath_format[] =
1254 "%/lib/resources.jar:"
1255 "%/lib/rt.jar:"
1256 "%/lib/sunrsasign.jar:"
1257 "%/lib/jsse.jar:"
1258 "%/lib/jce.jar:"
1259 "%/lib/charsets.jar:"
1260 "%/lib/jfr.jar:"
1261 #ifdef __APPLE__
1262 "%/lib/JObjC.jar:"
1263 #endif
1264 "%/classes";
1265 char* sysclasspath = format_boot_path(classpath_format, home, home_len, fileSep, pathSep);
1266 if (sysclasspath == NULL) return false;
1267 Arguments::set_sysclasspath(sysclasspath);
1268
1269 return true;
1270 }
1271
1272 /*
1273 * Splits a path, based on its separator, the number of
1274 * elements is returned back in n.
1275 * It is the callers responsibility to:
1276 * a> check the value of n, and n may be 0.
1277 * b> ignore any empty path elements
1278 * c> free up the data.
1279 */
1280 char** os::split_path(const char* path, int* n) {
1281 *n = 0;
1282 if (path == NULL || strlen(path) == 0) {
1283 return NULL;
1284 }
1285 const char psepchar = *os::path_separator();
1286 char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal);
1287 if (inpath == NULL) {
1288 return NULL;
1289 }
1290 strcpy(inpath, path);
1291 int count = 1;
1292 char* p = strchr(inpath, psepchar);
1293 // Get a count of elements to allocate memory
1294 while (p != NULL) {
1295 count++;
1296 p++;
1297 p = strchr(p, psepchar);
1298 }
1299 char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count, mtInternal);
1300 if (opath == NULL) {
1301 return NULL;
1302 }
1303
1304 // do the actual splitting
1305 p = inpath;
1306 for (int i = 0 ; i < count ; i++) {
1307 size_t len = strcspn(p, os::path_separator());
1308 if (len > JVM_MAXPATHLEN) {
1309 return NULL;
1310 }
1311 // allocate the string and add terminator storage
1312 char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
1313 if (s == NULL) {
1314 return NULL;
1315 }
1316 strncpy(s, p, len);
1317 s[len] = '\0';
1318 opath[i] = s;
1319 p += len + 1;
1320 }
1321 FREE_C_HEAP_ARRAY(char, inpath, mtInternal);
1322 *n = count;
1323 return opath;
1324 }
1325
1326 void os::set_memory_serialize_page(address page) {
1327 int count = log2_intptr(sizeof(class JavaThread)) - log2_intptr(64);
1328 _mem_serialize_page = (volatile int32_t *)page;
1329 // We initialize the serialization page shift count here
1330 // We assume a cache line size of 64 bytes
1331 assert(SerializePageShiftCount == count,
1332 "thread size changed, fix SerializePageShiftCount constant");
1333 set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t)));
1334 }
1335
1336 static volatile intptr_t SerializePageLock = 0;
1337
1338 // This method is called from signal handler when SIGSEGV occurs while the current
1339 // thread tries to store to the "read-only" memory serialize page during state
1340 // transition.
1341 void os::block_on_serialize_page_trap() {
1342 if (TraceSafepoint) {
1343 tty->print_cr("Block until the serialize page permission restored");
1344 }
1345 // When VMThread is holding the SerializePageLock during modifying the
1346 // access permission of the memory serialize page, the following call
1347 // will block until the permission of that page is restored to rw.
1348 // Generally, it is unsafe to manipulate locks in signal handlers, but in
1349 // this case, it's OK as the signal is synchronous and we know precisely when
1350 // it can occur.
1351 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page");
1352 Thread::muxRelease(&SerializePageLock);
1353 }
1354
1355 // Serialize all thread state variables
1356 void os::serialize_thread_states() {
1357 // On some platforms such as Solaris & Linux, the time duration of the page
1358 // permission restoration is observed to be much longer than expected due to
1359 // scheduler starvation problem etc. To avoid the long synchronization
1360 // time and expensive page trap spinning, 'SerializePageLock' is used to block
1361 // the mutator thread if such case is encountered. See bug 6546278 for details.
1362 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states");
1363 os::protect_memory((char *)os::get_memory_serialize_page(),
1364 os::vm_page_size(), MEM_PROT_READ);
1365 os::protect_memory((char *)os::get_memory_serialize_page(),
1366 os::vm_page_size(), MEM_PROT_RW);
1367 Thread::muxRelease(&SerializePageLock);
1368 }
1369
1370 // Returns true if the current stack pointer is above the stack shadow
1371 // pages, false otherwise.
1372
1373 bool os::stack_shadow_pages_available(Thread *thread, methodHandle method) {
1374 assert(StackRedPages > 0 && StackYellowPages > 0,"Sanity check");
1375 address sp = current_stack_pointer();
1376 // Check if we have StackShadowPages above the yellow zone. This parameter
1377 // is dependent on the depth of the maximum VM call stack possible from
1378 // the handler for stack overflow. 'instanceof' in the stack overflow
1379 // handler or a println uses at least 8k stack of VM and native code
1380 // respectively.
1381 const int framesize_in_bytes =
1382 Interpreter::size_top_interpreter_activation(method()) * wordSize;
1383 int reserved_area = ((StackShadowPages + StackRedPages + StackYellowPages)
1384 * vm_page_size()) + framesize_in_bytes;
1385 // The very lower end of the stack
1386 address stack_limit = thread->stack_base() - thread->stack_size();
1387 return (sp > (stack_limit + reserved_area));
1388 }
1389
1390 size_t os::page_size_for_region(size_t region_min_size, size_t region_max_size,
1391 uint min_pages)
1392 {
1393 assert(min_pages > 0, "sanity");
1394 if (UseLargePages) {
1395 const size_t max_page_size = region_max_size / min_pages;
1396
1397 for (unsigned int i = 0; _page_sizes[i] != 0; ++i) {
1398 const size_t sz = _page_sizes[i];
1399 const size_t mask = sz - 1;
1400 if ((region_min_size & mask) == 0 && (region_max_size & mask) == 0) {
1401 // The largest page size with no fragmentation.
1402 return sz;
1403 }
1404
1405 if (sz <= max_page_size) {
1406 // The largest page size that satisfies the min_pages requirement.
1407 return sz;
1408 }
1409 }
1410 }
1411
1412 return vm_page_size();
1413 }
1414
1415 #ifndef PRODUCT
1416 void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count)
1417 {
1418 if (TracePageSizes) {
1419 tty->print("%s: ", str);
1420 for (int i = 0; i < count; ++i) {
1421 tty->print(" " SIZE_FORMAT, page_sizes[i]);
1422 }
1423 tty->cr();
1424 }
1425 }
1426
1427 void os::trace_page_sizes(const char* str, const size_t region_min_size,
1428 const size_t region_max_size, const size_t page_size,
1429 const char* base, const size_t size)
1430 {
1431 if (TracePageSizes) {
1432 tty->print_cr("%s: min=" SIZE_FORMAT " max=" SIZE_FORMAT
1433 " pg_sz=" SIZE_FORMAT " base=" PTR_FORMAT
1434 " size=" SIZE_FORMAT,
1435 str, region_min_size, region_max_size,
1436 page_size, base, size);
1437 }
1438 }
1439 #endif // #ifndef PRODUCT
1440
1441 // This is the working definition of a server class machine:
1442 // >= 2 physical CPU's and >=2GB of memory, with some fuzz
1443 // because the graphics memory (?) sometimes masks physical memory.
1444 // If you want to change the definition of a server class machine
1445 // on some OS or platform, e.g., >=4GB on Windohs platforms,
1446 // then you'll have to parameterize this method based on that state,
1447 // as was done for logical processors here, or replicate and
1448 // specialize this method for each platform. (Or fix os to have
1449 // some inheritance structure and use subclassing. Sigh.)
1450 // If you want some platform to always or never behave as a server
1451 // class machine, change the setting of AlwaysActAsServerClassMachine
1452 // and NeverActAsServerClassMachine in globals*.hpp.
1453 bool os::is_server_class_machine() {
1454 // First check for the early returns
1455 if (NeverActAsServerClassMachine) {
1456 return false;
1457 }
1458 if (AlwaysActAsServerClassMachine) {
1459 return true;
1460 }
1461 // Then actually look at the machine
1462 bool result = false;
1463 const unsigned int server_processors = 2;
1464 const julong server_memory = 2UL * G;
1465 // We seem not to get our full complement of memory.
1466 // We allow some part (1/8?) of the memory to be "missing",
1467 // based on the sizes of DIMMs, and maybe graphics cards.
1468 const julong missing_memory = 256UL * M;
1469
1470 /* Is this a server class machine? */
1471 if ((os::active_processor_count() >= (int)server_processors) &&
1472 (os::physical_memory() >= (server_memory - missing_memory))) {
1473 const unsigned int logical_processors =
1474 VM_Version::logical_processors_per_package();
1475 if (logical_processors > 1) {
1476 const unsigned int physical_packages =
1477 os::active_processor_count() / logical_processors;
1478 if (physical_packages > server_processors) {
1479 result = true;
1480 }
1481 } else {
1482 result = true;
1483 }
1484 }
1485 return result;
1486 }
1487
1488 // Read file line by line, if line is longer than bsize,
1489 // skip rest of line.
1490 int os::get_line_chars(int fd, char* buf, const size_t bsize){
1491 size_t sz, i = 0;
1492
1493 // read until EOF, EOL or buf is full
1494 while ((sz = (int) read(fd, &buf[i], 1)) == 1 && i < (bsize-2) && buf[i] != '\n') {
1495 ++i;
1496 }
1497
1498 if (buf[i] == '\n') {
1499 // EOL reached so ignore EOL character and return
1500
1501 buf[i] = 0;
1502 return (int) i;
1503 }
1504
1505 buf[i+1] = 0;
1506
1507 if (sz != 1) {
1508 // EOF reached. if we read chars before EOF return them and
1509 // return EOF on next call otherwise return EOF
1510
1511 return (i == 0) ? -1 : (int) i;
1512 }
1513
1514 // line is longer than size of buf, skip to EOL
1515 char ch;
1516 while (read(fd, &ch, 1) == 1 && ch != '\n') {
1517 // Do nothing
1518 }
1519
1520 // return initial part of line that fits in buf.
1521 // If we reached EOF, it will be returned on next call.
1522
1523 return (int) i;
1524 }
1525
1526 void os::SuspendedThreadTask::run() {
1527 assert(Threads_lock->owned_by_self() || (_thread == VMThread::vm_thread()), "must have threads lock to call this");
1528 internal_do_task();
1529 _done = true;
1530 }
1531
1532 bool os::create_stack_guard_pages(char* addr, size_t bytes) {
1533 return os::pd_create_stack_guard_pages(addr, bytes);
1534 }
1535
1536 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint) {
1537 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1538 if (result != NULL) {
1539 MemTracker::record_virtual_memory_reserve((address)result, bytes, mtNone, CALLER_PC);
1540 }
1541
1542 return result;
1543 }
1544
1545 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint,
1546 MEMFLAGS flags) {
1547 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1548 if (result != NULL) {
1549 MemTracker::record_virtual_memory_reserve((address)result, bytes, mtNone, CALLER_PC);
1550 MemTracker::record_virtual_memory_type((address)result, flags);
1551 }
1552
1553 return result;
1554 }
1555
1556 char* os::attempt_reserve_memory_at(size_t bytes, char* addr) {
1557 char* result = pd_attempt_reserve_memory_at(bytes, addr);
1558 if (result != NULL) {
1559 MemTracker::record_virtual_memory_reserve((address)result, bytes, mtNone, CALLER_PC);
1560 }
1561 return result;
1562 }
1563
1564 void os::split_reserved_memory(char *base, size_t size,
1565 size_t split, bool realloc) {
1566 pd_split_reserved_memory(base, size, split, realloc);
1567 }
1568
1569 bool os::commit_memory(char* addr, size_t bytes, bool executable) {
1570 bool res = pd_commit_memory(addr, bytes, executable);
1571 if (res) {
1572 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1573 }
1574 return res;
1575 }
1576
1577 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint,
1578 bool executable) {
1579 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable);
1580 if (res) {
1581 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1582 }
1583 return res;
1584 }
1585
1586 void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable,
1587 const char* mesg) {
1588 pd_commit_memory_or_exit(addr, bytes, executable, mesg);
1589 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1590 }
1591
1592 void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint,
1593 bool executable, const char* mesg) {
1594 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg);
1595 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1596 }
1597
1598 bool os::uncommit_memory(char* addr, size_t bytes) {
1599 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_uncommit_tracker();
1600 bool res = pd_uncommit_memory(addr, bytes);
1601 if (res) {
1602 tkr.record((address)addr, bytes);
1603 } else {
1604 tkr.discard();
1605 }
1606 return res;
1607 }
1608
1609 bool os::release_memory(char* addr, size_t bytes) {
1610 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
1611 bool res = pd_release_memory(addr, bytes);
1612 if (res) {
1613 tkr.record((address)addr, bytes);
1614 } else {
1615 tkr.discard();
1616 }
1617 return res;
1618 }
1619
1620
1621 char* os::map_memory(int fd, const char* file_name, size_t file_offset,
1622 char *addr, size_t bytes, bool read_only,
1623 bool allow_exec) {
1624 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec);
1625 if (result != NULL) {
1626 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, mtNone, CALLER_PC);
1627 }
1628 return result;
1629 }
1630
1631 char* os::remap_memory(int fd, const char* file_name, size_t file_offset,
1632 char *addr, size_t bytes, bool read_only,
1633 bool allow_exec) {
1634 return pd_remap_memory(fd, file_name, file_offset, addr, bytes,
1635 read_only, allow_exec);
1636 }
1637
1638 bool os::unmap_memory(char *addr, size_t bytes) {
1639 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
1640 bool result = pd_unmap_memory(addr, bytes);
1641 if (result) {
1642 tkr.record((address)addr, bytes);
1643 } else {
1644 tkr.discard();
1645 }
1646 return result;
1647 }
1648
1649 void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) {
1650 pd_free_memory(addr, bytes, alignment_hint);
1651 }
1652
1653 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
1654 pd_realign_memory(addr, bytes, alignment_hint);
1655 }
1656
1657 #ifndef TARGET_OS_FAMILY_windows
1658 /* try to switch state from state "from" to state "to"
1659 * returns the state set after the method is complete
1660 */
1661 os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from,
1662 os::SuspendResume::State to)
1663 {
1664 os::SuspendResume::State result =
1665 (os::SuspendResume::State) Atomic::cmpxchg((jint) to, (jint *) &_state, (jint) from);
1666 if (result == from) {
1667 // success
1668 return to;
1669 }
1670 return result;
1671 }
1672 #endif