Tue, 24 Dec 2013 11:48:39 -0800
8029233: Update copyright year to match last edit in jdk8 hotspot repository for 2013
Summary: Copyright year updated for files modified during 2013
Reviewed-by: twisti, iveresov
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 */
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
66 # include <signal.h>
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];
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
83 static juint cur_malloc_words = 0; // current size for MallocMaxTestWords
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 }
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;
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
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);
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 }
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
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 }
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;
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 }
223 // --------------------- sun.misc.Signal (optional) ---------------------
226 // SIGBREAK is sent by the keyboard to query the VM state
227 #ifndef SIGBREAK
228 #define SIGBREAK SIGQUIT
229 #endif
231 // sigexitnum_pd is a platform-specific special signal used for terminating the Signal thread.
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 }
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 }
317 void os::init_before_ergo() {
318 // We need to initialize large page support here because ergonomics takes some
319 // decisions depending on large page support and the calculated large page size.
320 large_page_init();
321 }
323 void os::signal_init() {
324 if (!ReduceSignalUsage) {
325 // Setup JavaThread for processing signals
326 EXCEPTION_MARK;
327 Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(), true, CHECK);
328 instanceKlassHandle klass (THREAD, k);
329 instanceHandle thread_oop = klass->allocate_instance_handle(CHECK);
331 const char thread_name[] = "Signal Dispatcher";
332 Handle string = java_lang_String::create_from_str(thread_name, CHECK);
334 // Initialize thread_oop to put it into the system threadGroup
335 Handle thread_group (THREAD, Universe::system_thread_group());
336 JavaValue result(T_VOID);
337 JavaCalls::call_special(&result, thread_oop,
338 klass,
339 vmSymbols::object_initializer_name(),
340 vmSymbols::threadgroup_string_void_signature(),
341 thread_group,
342 string,
343 CHECK);
345 KlassHandle group(THREAD, SystemDictionary::ThreadGroup_klass());
346 JavaCalls::call_special(&result,
347 thread_group,
348 group,
349 vmSymbols::add_method_name(),
350 vmSymbols::thread_void_signature(),
351 thread_oop, // ARG 1
352 CHECK);
354 os::signal_init_pd();
356 { MutexLocker mu(Threads_lock);
357 JavaThread* signal_thread = new JavaThread(&signal_thread_entry);
359 // At this point it may be possible that no osthread was created for the
360 // JavaThread due to lack of memory. We would have to throw an exception
361 // in that case. However, since this must work and we do not allow
362 // exceptions anyway, check and abort if this fails.
363 if (signal_thread == NULL || signal_thread->osthread() == NULL) {
364 vm_exit_during_initialization("java.lang.OutOfMemoryError",
365 "unable to create new native thread");
366 }
368 java_lang_Thread::set_thread(thread_oop(), signal_thread);
369 java_lang_Thread::set_priority(thread_oop(), NearMaxPriority);
370 java_lang_Thread::set_daemon(thread_oop());
372 signal_thread->set_threadObj(thread_oop());
373 Threads::add(signal_thread);
374 Thread::start(signal_thread);
375 }
376 // Handle ^BREAK
377 os::signal(SIGBREAK, os::user_handler());
378 }
379 }
382 void os::terminate_signal_thread() {
383 if (!ReduceSignalUsage)
384 signal_notify(sigexitnum_pd());
385 }
388 // --------------------- loading libraries ---------------------
390 typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *);
391 extern struct JavaVM_ main_vm;
393 static void* _native_java_library = NULL;
395 void* os::native_java_library() {
396 if (_native_java_library == NULL) {
397 char buffer[JVM_MAXPATHLEN];
398 char ebuf[1024];
400 // Try to load verify dll first. In 1.3 java dll depends on it and is not
401 // always able to find it when the loading executable is outside the JDK.
402 // In order to keep working with 1.2 we ignore any loading errors.
403 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
404 "verify")) {
405 dll_load(buffer, ebuf, sizeof(ebuf));
406 }
408 // Load java dll
409 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
410 "java")) {
411 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf));
412 }
413 if (_native_java_library == NULL) {
414 vm_exit_during_initialization("Unable to load native library", ebuf);
415 }
417 #if defined(__OpenBSD__)
418 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so
419 // ignore errors
420 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
421 "net")) {
422 dll_load(buffer, ebuf, sizeof(ebuf));
423 }
424 #endif
425 }
426 static jboolean onLoaded = JNI_FALSE;
427 if (onLoaded) {
428 // We may have to wait to fire OnLoad until TLS is initialized.
429 if (ThreadLocalStorage::is_initialized()) {
430 // The JNI_OnLoad handling is normally done by method load in
431 // java.lang.ClassLoader$NativeLibrary, but the VM loads the base library
432 // explicitly so we have to check for JNI_OnLoad as well
433 const char *onLoadSymbols[] = JNI_ONLOAD_SYMBOLS;
434 JNI_OnLoad_t JNI_OnLoad = CAST_TO_FN_PTR(
435 JNI_OnLoad_t, dll_lookup(_native_java_library, onLoadSymbols[0]));
436 if (JNI_OnLoad != NULL) {
437 JavaThread* thread = JavaThread::current();
438 ThreadToNativeFromVM ttn(thread);
439 HandleMark hm(thread);
440 jint ver = (*JNI_OnLoad)(&main_vm, NULL);
441 onLoaded = JNI_TRUE;
442 if (!Threads::is_supported_jni_version_including_1_1(ver)) {
443 vm_exit_during_initialization("Unsupported JNI version");
444 }
445 }
446 }
447 }
448 return _native_java_library;
449 }
451 /*
452 * Support for finding Agent_On(Un)Load/Attach<_lib_name> if it exists.
453 * If check_lib == true then we are looking for an
454 * Agent_OnLoad_lib_name or Agent_OnAttach_lib_name function to determine if
455 * this library is statically linked into the image.
456 * If check_lib == false then we will look for the appropriate symbol in the
457 * executable if agent_lib->is_static_lib() == true or in the shared library
458 * referenced by 'handle'.
459 */
460 void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib,
461 const char *syms[], size_t syms_len) {
462 assert(agent_lib != NULL, "sanity check");
463 const char *lib_name;
464 void *handle = agent_lib->os_lib();
465 void *entryName = NULL;
466 char *agent_function_name;
467 size_t i;
469 // If checking then use the agent name otherwise test is_static_lib() to
470 // see how to process this lookup
471 lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL);
472 for (i = 0; i < syms_len; i++) {
473 agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path());
474 if (agent_function_name == NULL) {
475 break;
476 }
477 entryName = dll_lookup(handle, agent_function_name);
478 FREE_C_HEAP_ARRAY(char, agent_function_name, mtThread);
479 if (entryName != NULL) {
480 break;
481 }
482 }
483 return entryName;
484 }
486 // See if the passed in agent is statically linked into the VM image.
487 bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
488 size_t syms_len) {
489 void *ret;
490 void *proc_handle;
491 void *save_handle;
493 assert(agent_lib != NULL, "sanity check");
494 if (agent_lib->name() == NULL) {
495 return false;
496 }
497 proc_handle = get_default_process_handle();
498 // Check for Agent_OnLoad/Attach_lib_name function
499 save_handle = agent_lib->os_lib();
500 // We want to look in this process' symbol table.
501 agent_lib->set_os_lib(proc_handle);
502 ret = find_agent_function(agent_lib, true, syms, syms_len);
503 if (ret != NULL) {
504 // Found an entry point like Agent_OnLoad_lib_name so we have a static agent
505 agent_lib->set_valid();
506 agent_lib->set_static_lib(true);
507 return true;
508 }
509 agent_lib->set_os_lib(save_handle);
510 return false;
511 }
513 // --------------------- heap allocation utilities ---------------------
515 char *os::strdup(const char *str, MEMFLAGS flags) {
516 size_t size = strlen(str);
517 char *dup_str = (char *)malloc(size + 1, flags);
518 if (dup_str == NULL) return NULL;
519 strcpy(dup_str, str);
520 return dup_str;
521 }
525 #ifdef ASSERT
526 #define space_before (MallocCushion + sizeof(double))
527 #define space_after MallocCushion
528 #define size_addr_from_base(p) (size_t*)(p + space_before - sizeof(size_t))
529 #define size_addr_from_obj(p) ((size_t*)p - 1)
530 // MallocCushion: size of extra cushion allocated around objects with +UseMallocOnly
531 // NB: cannot be debug variable, because these aren't set from the command line until
532 // *after* the first few allocs already happened
533 #define MallocCushion 16
534 #else
535 #define space_before 0
536 #define space_after 0
537 #define size_addr_from_base(p) should not use w/o ASSERT
538 #define size_addr_from_obj(p) should not use w/o ASSERT
539 #define MallocCushion 0
540 #endif
541 #define paranoid 0 /* only set to 1 if you suspect checking code has bug */
543 #ifdef ASSERT
544 inline size_t get_size(void* obj) {
545 size_t size = *size_addr_from_obj(obj);
546 if (size < 0) {
547 fatal(err_msg("free: size field of object #" PTR_FORMAT " was overwritten ("
548 SIZE_FORMAT ")", obj, size));
549 }
550 return size;
551 }
553 u_char* find_cushion_backwards(u_char* start) {
554 u_char* p = start;
555 while (p[ 0] != badResourceValue || p[-1] != badResourceValue ||
556 p[-2] != badResourceValue || p[-3] != badResourceValue) p--;
557 // ok, we have four consecutive marker bytes; find start
558 u_char* q = p - 4;
559 while (*q == badResourceValue) q--;
560 return q + 1;
561 }
563 u_char* find_cushion_forwards(u_char* start) {
564 u_char* p = start;
565 while (p[0] != badResourceValue || p[1] != badResourceValue ||
566 p[2] != badResourceValue || p[3] != badResourceValue) p++;
567 // ok, we have four consecutive marker bytes; find end of cushion
568 u_char* q = p + 4;
569 while (*q == badResourceValue) q++;
570 return q - MallocCushion;
571 }
573 void print_neighbor_blocks(void* ptr) {
574 // find block allocated before ptr (not entirely crash-proof)
575 if (MallocCushion < 4) {
576 tty->print_cr("### cannot find previous block (MallocCushion < 4)");
577 return;
578 }
579 u_char* start_of_this_block = (u_char*)ptr - space_before;
580 u_char* end_of_prev_block_data = start_of_this_block - space_after -1;
581 // look for cushion in front of prev. block
582 u_char* start_of_prev_block = find_cushion_backwards(end_of_prev_block_data);
583 ptrdiff_t size = *size_addr_from_base(start_of_prev_block);
584 u_char* obj = start_of_prev_block + space_before;
585 if (size <= 0 ) {
586 // start is bad; mayhave been confused by OS data inbetween objects
587 // search one more backwards
588 start_of_prev_block = find_cushion_backwards(start_of_prev_block);
589 size = *size_addr_from_base(start_of_prev_block);
590 obj = start_of_prev_block + space_before;
591 }
593 if (start_of_prev_block + space_before + size + space_after == start_of_this_block) {
594 tty->print_cr("### previous object: " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", obj, size);
595 } else {
596 tty->print_cr("### previous object (not sure if correct): " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", obj, size);
597 }
599 // now find successor block
600 u_char* start_of_next_block = (u_char*)ptr + *size_addr_from_obj(ptr) + space_after;
601 start_of_next_block = find_cushion_forwards(start_of_next_block);
602 u_char* next_obj = start_of_next_block + space_before;
603 ptrdiff_t next_size = *size_addr_from_base(start_of_next_block);
604 if (start_of_next_block[0] == badResourceValue &&
605 start_of_next_block[1] == badResourceValue &&
606 start_of_next_block[2] == badResourceValue &&
607 start_of_next_block[3] == badResourceValue) {
608 tty->print_cr("### next object: " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", next_obj, next_size);
609 } else {
610 tty->print_cr("### next object (not sure if correct): " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", next_obj, next_size);
611 }
612 }
615 void report_heap_error(void* memblock, void* bad, const char* where) {
616 tty->print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees);
617 tty->print_cr("## memory stomp: byte at " PTR_FORMAT " %s object " PTR_FORMAT, bad, where, memblock);
618 print_neighbor_blocks(memblock);
619 fatal("memory stomping error");
620 }
622 void verify_block(void* memblock) {
623 size_t size = get_size(memblock);
624 if (MallocCushion) {
625 u_char* ptr = (u_char*)memblock - space_before;
626 for (int i = 0; i < MallocCushion; i++) {
627 if (ptr[i] != badResourceValue) {
628 report_heap_error(memblock, ptr+i, "in front of");
629 }
630 }
631 u_char* end = (u_char*)memblock + size + space_after;
632 for (int j = -MallocCushion; j < 0; j++) {
633 if (end[j] != badResourceValue) {
634 report_heap_error(memblock, end+j, "after");
635 }
636 }
637 }
638 }
639 #endif
641 //
642 // This function supports testing of the malloc out of memory
643 // condition without really running the system out of memory.
644 //
645 static u_char* testMalloc(size_t alloc_size) {
646 assert(MallocMaxTestWords > 0, "sanity check");
648 if ((cur_malloc_words + (alloc_size / BytesPerWord)) > MallocMaxTestWords) {
649 return NULL;
650 }
652 u_char* ptr = (u_char*)::malloc(alloc_size);
654 if (ptr != NULL) {
655 Atomic::add(((jint) (alloc_size / BytesPerWord)),
656 (volatile jint *) &cur_malloc_words);
657 }
658 return ptr;
659 }
661 void* os::malloc(size_t size, MEMFLAGS memflags, address caller) {
662 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
663 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
665 #ifdef ASSERT
666 // checking for the WatcherThread and crash_protection first
667 // since os::malloc can be called when the libjvm.{dll,so} is
668 // first loaded and we don't have a thread yet.
669 // try to find the thread after we see that the watcher thread
670 // exists and has crash protection.
671 WatcherThread *wt = WatcherThread::watcher_thread();
672 if (wt != NULL && wt->has_crash_protection()) {
673 Thread* thread = ThreadLocalStorage::get_thread_slow();
674 if (thread == wt) {
675 assert(!wt->has_crash_protection(),
676 "Can't malloc with crash protection from WatcherThread");
677 }
678 }
679 #endif
681 if (size == 0) {
682 // return a valid pointer if size is zero
683 // if NULL is returned the calling functions assume out of memory.
684 size = 1;
685 }
687 const size_t alloc_size = size + space_before + space_after;
689 if (size > alloc_size) { // Check for rollover.
690 return NULL;
691 }
693 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
695 u_char* ptr;
697 if (MallocMaxTestWords > 0) {
698 ptr = testMalloc(alloc_size);
699 } else {
700 ptr = (u_char*)::malloc(alloc_size);
701 }
703 #ifdef ASSERT
704 if (ptr == NULL) return NULL;
705 if (MallocCushion) {
706 for (u_char* p = ptr; p < ptr + MallocCushion; p++) *p = (u_char)badResourceValue;
707 u_char* end = ptr + space_before + size;
708 for (u_char* pq = ptr+MallocCushion; pq < end; pq++) *pq = (u_char)uninitBlockPad;
709 for (u_char* q = end; q < end + MallocCushion; q++) *q = (u_char)badResourceValue;
710 }
711 // put size just before data
712 *size_addr_from_base(ptr) = size;
713 #endif
714 u_char* memblock = ptr + space_before;
715 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
716 tty->print_cr("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, memblock);
717 breakpoint();
718 }
719 debug_only(if (paranoid) verify_block(memblock));
720 if (PrintMalloc && tty != NULL) tty->print_cr("os::malloc " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, memblock);
722 // we do not track MallocCushion memory
723 MemTracker::record_malloc((address)memblock, size, memflags, caller == 0 ? CALLER_PC : caller);
725 return memblock;
726 }
729 void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, address caller) {
730 #ifndef ASSERT
731 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
732 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
733 MemTracker::Tracker tkr = MemTracker::get_realloc_tracker();
734 void* ptr = ::realloc(memblock, size);
735 if (ptr != NULL) {
736 tkr.record((address)memblock, (address)ptr, size, memflags,
737 caller == 0 ? CALLER_PC : caller);
738 } else {
739 tkr.discard();
740 }
741 return ptr;
742 #else
743 if (memblock == NULL) {
744 return malloc(size, memflags, (caller == 0 ? CALLER_PC : caller));
745 }
746 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
747 tty->print_cr("os::realloc caught " PTR_FORMAT, memblock);
748 breakpoint();
749 }
750 verify_block(memblock);
751 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
752 if (size == 0) return NULL;
753 // always move the block
754 void* ptr = malloc(size, memflags, caller == 0 ? CALLER_PC : caller);
755 if (PrintMalloc) tty->print_cr("os::remalloc " SIZE_FORMAT " bytes, " PTR_FORMAT " --> " PTR_FORMAT, size, memblock, ptr);
756 // Copy to new memory if malloc didn't fail
757 if ( ptr != NULL ) {
758 memcpy(ptr, memblock, MIN2(size, get_size(memblock)));
759 if (paranoid) verify_block(ptr);
760 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) {
761 tty->print_cr("os::realloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr);
762 breakpoint();
763 }
764 free(memblock);
765 }
766 return ptr;
767 #endif
768 }
771 void os::free(void *memblock, MEMFLAGS memflags) {
772 NOT_PRODUCT(inc_stat_counter(&num_frees, 1));
773 #ifdef ASSERT
774 if (memblock == NULL) return;
775 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
776 if (tty != NULL) tty->print_cr("os::free caught " PTR_FORMAT, memblock);
777 breakpoint();
778 }
779 verify_block(memblock);
780 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
781 // Added by detlefs.
782 if (MallocCushion) {
783 u_char* ptr = (u_char*)memblock - space_before;
784 for (u_char* p = ptr; p < ptr + MallocCushion; p++) {
785 guarantee(*p == badResourceValue,
786 "Thing freed should be malloc result.");
787 *p = (u_char)freeBlockPad;
788 }
789 size_t size = get_size(memblock);
790 inc_stat_counter(&free_bytes, size);
791 u_char* end = ptr + space_before + size;
792 for (u_char* q = end; q < end + MallocCushion; q++) {
793 guarantee(*q == badResourceValue,
794 "Thing freed should be malloc result.");
795 *q = (u_char)freeBlockPad;
796 }
797 if (PrintMalloc && tty != NULL)
798 fprintf(stderr, "os::free " SIZE_FORMAT " bytes --> " PTR_FORMAT "\n", size, (uintptr_t)memblock);
799 } else if (PrintMalloc && tty != NULL) {
800 // tty->print_cr("os::free %p", memblock);
801 fprintf(stderr, "os::free " PTR_FORMAT "\n", (uintptr_t)memblock);
802 }
803 #endif
804 MemTracker::record_free((address)memblock, memflags);
806 ::free((char*)memblock - space_before);
807 }
809 void os::init_random(long initval) {
810 _rand_seed = initval;
811 }
814 long os::random() {
815 /* standard, well-known linear congruential random generator with
816 * next_rand = (16807*seed) mod (2**31-1)
817 * see
818 * (1) "Random Number Generators: Good Ones Are Hard to Find",
819 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988),
820 * (2) "Two Fast Implementations of the 'Minimal Standard' Random
821 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88.
822 */
823 const long a = 16807;
824 const unsigned long m = 2147483647;
825 const long q = m / a; assert(q == 127773, "weird math");
826 const long r = m % a; assert(r == 2836, "weird math");
828 // compute az=2^31p+q
829 unsigned long lo = a * (long)(_rand_seed & 0xFFFF);
830 unsigned long hi = a * (long)((unsigned long)_rand_seed >> 16);
831 lo += (hi & 0x7FFF) << 16;
833 // if q overflowed, ignore the overflow and increment q
834 if (lo > m) {
835 lo &= m;
836 ++lo;
837 }
838 lo += hi >> 15;
840 // if (p+q) overflowed, ignore the overflow and increment (p+q)
841 if (lo > m) {
842 lo &= m;
843 ++lo;
844 }
845 return (_rand_seed = lo);
846 }
848 // The INITIALIZED state is distinguished from the SUSPENDED state because the
849 // conditions in which a thread is first started are different from those in which
850 // a suspension is resumed. These differences make it hard for us to apply the
851 // tougher checks when starting threads that we want to do when resuming them.
852 // However, when start_thread is called as a result of Thread.start, on a Java
853 // thread, the operation is synchronized on the Java Thread object. So there
854 // cannot be a race to start the thread and hence for the thread to exit while
855 // we are working on it. Non-Java threads that start Java threads either have
856 // to do so in a context in which races are impossible, or should do appropriate
857 // locking.
859 void os::start_thread(Thread* thread) {
860 // guard suspend/resume
861 MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag);
862 OSThread* osthread = thread->osthread();
863 osthread->set_state(RUNNABLE);
864 pd_start_thread(thread);
865 }
867 //---------------------------------------------------------------------------
868 // Helper functions for fatal error handler
870 void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) {
871 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking");
873 int cols = 0;
874 int cols_per_line = 0;
875 switch (unitsize) {
876 case 1: cols_per_line = 16; break;
877 case 2: cols_per_line = 8; break;
878 case 4: cols_per_line = 4; break;
879 case 8: cols_per_line = 2; break;
880 default: return;
881 }
883 address p = start;
884 st->print(PTR_FORMAT ": ", start);
885 while (p < end) {
886 switch (unitsize) {
887 case 1: st->print("%02x", *(u1*)p); break;
888 case 2: st->print("%04x", *(u2*)p); break;
889 case 4: st->print("%08x", *(u4*)p); break;
890 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break;
891 }
892 p += unitsize;
893 cols++;
894 if (cols >= cols_per_line && p < end) {
895 cols = 0;
896 st->cr();
897 st->print(PTR_FORMAT ": ", p);
898 } else {
899 st->print(" ");
900 }
901 }
902 st->cr();
903 }
905 void os::print_environment_variables(outputStream* st, const char** env_list,
906 char* buffer, int len) {
907 if (env_list) {
908 st->print_cr("Environment Variables:");
910 for (int i = 0; env_list[i] != NULL; i++) {
911 if (getenv(env_list[i], buffer, len)) {
912 st->print(env_list[i]);
913 st->print("=");
914 st->print_cr(buffer);
915 }
916 }
917 }
918 }
920 void os::print_cpu_info(outputStream* st) {
921 // cpu
922 st->print("CPU:");
923 st->print("total %d", os::processor_count());
924 // It's not safe to query number of active processors after crash
925 // st->print("(active %d)", os::active_processor_count());
926 st->print(" %s", VM_Version::cpu_features());
927 st->cr();
928 pd_print_cpu_info(st);
929 }
931 void os::print_date_and_time(outputStream *st) {
932 time_t tloc;
933 (void)time(&tloc);
934 st->print("time: %s", ctime(&tloc)); // ctime adds newline.
936 double t = os::elapsedTime();
937 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in
938 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int
939 // before printf. We lost some precision, but who cares?
940 st->print_cr("elapsed time: %d seconds", (int)t);
941 }
943 // moved from debug.cpp (used to be find()) but still called from there
944 // The verbose parameter is only set by the debug code in one case
945 void os::print_location(outputStream* st, intptr_t x, bool verbose) {
946 address addr = (address)x;
947 CodeBlob* b = CodeCache::find_blob_unsafe(addr);
948 if (b != NULL) {
949 if (b->is_buffer_blob()) {
950 // the interpreter is generated into a buffer blob
951 InterpreterCodelet* i = Interpreter::codelet_containing(addr);
952 if (i != NULL) {
953 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an Interpreter codelet", addr, (int)(addr - i->code_begin()));
954 i->print_on(st);
955 return;
956 }
957 if (Interpreter::contains(addr)) {
958 st->print_cr(INTPTR_FORMAT " is pointing into interpreter code"
959 " (not bytecode specific)", addr);
960 return;
961 }
962 //
963 if (AdapterHandlerLibrary::contains(b)) {
964 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an AdapterHandler", addr, (int)(addr - b->code_begin()));
965 AdapterHandlerLibrary::print_handler_on(st, b);
966 }
967 // the stubroutines are generated into a buffer blob
968 StubCodeDesc* d = StubCodeDesc::desc_for(addr);
969 if (d != NULL) {
970 st->print_cr(INTPTR_FORMAT " is at begin+%d in a stub", addr, (int)(addr - d->begin()));
971 d->print_on(st);
972 st->cr();
973 return;
974 }
975 if (StubRoutines::contains(addr)) {
976 st->print_cr(INTPTR_FORMAT " is pointing to an (unnamed) "
977 "stub routine", addr);
978 return;
979 }
980 // the InlineCacheBuffer is using stubs generated into a buffer blob
981 if (InlineCacheBuffer::contains(addr)) {
982 st->print_cr(INTPTR_FORMAT " is pointing into InlineCacheBuffer", addr);
983 return;
984 }
985 VtableStub* v = VtableStubs::stub_containing(addr);
986 if (v != NULL) {
987 st->print_cr(INTPTR_FORMAT " is at entry_point+%d in a vtable stub", addr, (int)(addr - v->entry_point()));
988 v->print_on(st);
989 st->cr();
990 return;
991 }
992 }
993 nmethod* nm = b->as_nmethod_or_null();
994 if (nm != NULL) {
995 ResourceMark rm;
996 st->print(INTPTR_FORMAT " is at entry_point+%d in (nmethod*)" INTPTR_FORMAT,
997 addr, (int)(addr - nm->entry_point()), nm);
998 if (verbose) {
999 st->print(" for ");
1000 nm->method()->print_value_on(st);
1001 }
1002 st->cr();
1003 nm->print_nmethod(verbose);
1004 return;
1005 }
1006 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in ", addr, (int)(addr - b->code_begin()));
1007 b->print_on(st);
1008 return;
1009 }
1011 if (Universe::heap()->is_in(addr)) {
1012 HeapWord* p = Universe::heap()->block_start(addr);
1013 bool print = false;
1014 // If we couldn't find it it just may mean that heap wasn't parseable
1015 // See if we were just given an oop directly
1016 if (p != NULL && Universe::heap()->block_is_obj(p)) {
1017 print = true;
1018 } else if (p == NULL && ((oopDesc*)addr)->is_oop()) {
1019 p = (HeapWord*) addr;
1020 print = true;
1021 }
1022 if (print) {
1023 if (p == (HeapWord*) addr) {
1024 st->print_cr(INTPTR_FORMAT " is an oop", addr);
1025 } else {
1026 st->print_cr(INTPTR_FORMAT " is pointing into object: " INTPTR_FORMAT, addr, p);
1027 }
1028 oop(p)->print_on(st);
1029 return;
1030 }
1031 } else {
1032 if (Universe::heap()->is_in_reserved(addr)) {
1033 st->print_cr(INTPTR_FORMAT " is an unallocated location "
1034 "in the heap", addr);
1035 return;
1036 }
1037 }
1038 if (JNIHandles::is_global_handle((jobject) addr)) {
1039 st->print_cr(INTPTR_FORMAT " is a global jni handle", addr);
1040 return;
1041 }
1042 if (JNIHandles::is_weak_global_handle((jobject) addr)) {
1043 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", addr);
1044 return;
1045 }
1046 #ifndef PRODUCT
1047 // we don't keep the block list in product mode
1048 if (JNIHandleBlock::any_contains((jobject) addr)) {
1049 st->print_cr(INTPTR_FORMAT " is a local jni handle", addr);
1050 return;
1051 }
1052 #endif
1054 for(JavaThread *thread = Threads::first(); thread; thread = thread->next()) {
1055 // Check for privilege stack
1056 if (thread->privileged_stack_top() != NULL &&
1057 thread->privileged_stack_top()->contains(addr)) {
1058 st->print_cr(INTPTR_FORMAT " is pointing into the privilege stack "
1059 "for thread: " INTPTR_FORMAT, addr, thread);
1060 if (verbose) thread->print_on(st);
1061 return;
1062 }
1063 // If the addr is a java thread print information about that.
1064 if (addr == (address)thread) {
1065 if (verbose) {
1066 thread->print_on(st);
1067 } else {
1068 st->print_cr(INTPTR_FORMAT " is a thread", addr);
1069 }
1070 return;
1071 }
1072 // If the addr is in the stack region for this thread then report that
1073 // and print thread info
1074 if (thread->stack_base() >= addr &&
1075 addr > (thread->stack_base() - thread->stack_size())) {
1076 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: "
1077 INTPTR_FORMAT, addr, thread);
1078 if (verbose) thread->print_on(st);
1079 return;
1080 }
1082 }
1084 #ifndef PRODUCT
1085 // Check if in metaspace.
1086 if (ClassLoaderDataGraph::contains((address)addr)) {
1087 // Use addr->print() from the debugger instead (not here)
1088 st->print_cr(INTPTR_FORMAT
1089 " is pointing into metadata", addr);
1090 return;
1091 }
1092 #endif
1094 // Try an OS specific find
1095 if (os::find(addr, st)) {
1096 return;
1097 }
1099 st->print_cr(INTPTR_FORMAT " is an unknown value", addr);
1100 }
1102 // Looks like all platforms except IA64 can use the same function to check
1103 // if C stack is walkable beyond current frame. The check for fp() is not
1104 // necessary on Sparc, but it's harmless.
1105 bool os::is_first_C_frame(frame* fr) {
1106 #if defined(IA64) && !defined(_WIN32)
1107 // On IA64 we have to check if the callers bsp is still valid
1108 // (i.e. within the register stack bounds).
1109 // Notice: this only works for threads created by the VM and only if
1110 // we walk the current stack!!! If we want to be able to walk
1111 // arbitrary other threads, we'll have to somehow store the thread
1112 // object in the frame.
1113 Thread *thread = Thread::current();
1114 if ((address)fr->fp() <=
1115 thread->register_stack_base() HPUX_ONLY(+ 0x0) LINUX_ONLY(+ 0x50)) {
1116 // This check is a little hacky, because on Linux the first C
1117 // frame's ('start_thread') register stack frame starts at
1118 // "register_stack_base + 0x48" while on HPUX, the first C frame's
1119 // ('__pthread_bound_body') register stack frame seems to really
1120 // start at "register_stack_base".
1121 return true;
1122 } else {
1123 return false;
1124 }
1125 #elif defined(IA64) && defined(_WIN32)
1126 return true;
1127 #else
1128 // Load up sp, fp, sender sp and sender fp, check for reasonable values.
1129 // Check usp first, because if that's bad the other accessors may fault
1130 // on some architectures. Ditto ufp second, etc.
1131 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1);
1132 // sp on amd can be 32 bit aligned.
1133 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1);
1135 uintptr_t usp = (uintptr_t)fr->sp();
1136 if ((usp & sp_align_mask) != 0) return true;
1138 uintptr_t ufp = (uintptr_t)fr->fp();
1139 if ((ufp & fp_align_mask) != 0) return true;
1141 uintptr_t old_sp = (uintptr_t)fr->sender_sp();
1142 if ((old_sp & sp_align_mask) != 0) return true;
1143 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true;
1145 uintptr_t old_fp = (uintptr_t)fr->link();
1146 if ((old_fp & fp_align_mask) != 0) return true;
1147 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true;
1149 // stack grows downwards; if old_fp is below current fp or if the stack
1150 // frame is too large, either the stack is corrupted or fp is not saved
1151 // on stack (i.e. on x86, ebp may be used as general register). The stack
1152 // is not walkable beyond current frame.
1153 if (old_fp < ufp) return true;
1154 if (old_fp - ufp > 64 * K) return true;
1156 return false;
1157 #endif
1158 }
1160 #ifdef ASSERT
1161 extern "C" void test_random() {
1162 const double m = 2147483647;
1163 double mean = 0.0, variance = 0.0, t;
1164 long reps = 10000;
1165 unsigned long seed = 1;
1167 tty->print_cr("seed %ld for %ld repeats...", seed, reps);
1168 os::init_random(seed);
1169 long num;
1170 for (int k = 0; k < reps; k++) {
1171 num = os::random();
1172 double u = (double)num / m;
1173 assert(u >= 0.0 && u <= 1.0, "bad random number!");
1175 // calculate mean and variance of the random sequence
1176 mean += u;
1177 variance += (u*u);
1178 }
1179 mean /= reps;
1180 variance /= (reps - 1);
1182 assert(num == 1043618065, "bad seed");
1183 tty->print_cr("mean of the 1st 10000 numbers: %f", mean);
1184 tty->print_cr("variance of the 1st 10000 numbers: %f", variance);
1185 const double eps = 0.0001;
1186 t = fabsd(mean - 0.5018);
1187 assert(t < eps, "bad mean");
1188 t = (variance - 0.3355) < 0.0 ? -(variance - 0.3355) : variance - 0.3355;
1189 assert(t < eps, "bad variance");
1190 }
1191 #endif
1194 // Set up the boot classpath.
1196 char* os::format_boot_path(const char* format_string,
1197 const char* home,
1198 int home_len,
1199 char fileSep,
1200 char pathSep) {
1201 assert((fileSep == '/' && pathSep == ':') ||
1202 (fileSep == '\\' && pathSep == ';'), "unexpected seperator chars");
1204 // Scan the format string to determine the length of the actual
1205 // boot classpath, and handle platform dependencies as well.
1206 int formatted_path_len = 0;
1207 const char* p;
1208 for (p = format_string; *p != 0; ++p) {
1209 if (*p == '%') formatted_path_len += home_len - 1;
1210 ++formatted_path_len;
1211 }
1213 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal);
1214 if (formatted_path == NULL) {
1215 return NULL;
1216 }
1218 // Create boot classpath from format, substituting separator chars and
1219 // java home directory.
1220 char* q = formatted_path;
1221 for (p = format_string; *p != 0; ++p) {
1222 switch (*p) {
1223 case '%':
1224 strcpy(q, home);
1225 q += home_len;
1226 break;
1227 case '/':
1228 *q++ = fileSep;
1229 break;
1230 case ':':
1231 *q++ = pathSep;
1232 break;
1233 default:
1234 *q++ = *p;
1235 }
1236 }
1237 *q = '\0';
1239 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched");
1240 return formatted_path;
1241 }
1244 bool os::set_boot_path(char fileSep, char pathSep) {
1245 const char* home = Arguments::get_java_home();
1246 int home_len = (int)strlen(home);
1248 static const char* meta_index_dir_format = "%/lib/";
1249 static const char* meta_index_format = "%/lib/meta-index";
1250 char* meta_index = format_boot_path(meta_index_format, home, home_len, fileSep, pathSep);
1251 if (meta_index == NULL) return false;
1252 char* meta_index_dir = format_boot_path(meta_index_dir_format, home, home_len, fileSep, pathSep);
1253 if (meta_index_dir == NULL) return false;
1254 Arguments::set_meta_index_path(meta_index, meta_index_dir);
1256 // Any modification to the JAR-file list, for the boot classpath must be
1257 // aligned with install/install/make/common/Pack.gmk. Note: boot class
1258 // path class JARs, are stripped for StackMapTable to reduce download size.
1259 static const char classpath_format[] =
1260 "%/lib/resources.jar:"
1261 "%/lib/rt.jar:"
1262 "%/lib/sunrsasign.jar:"
1263 "%/lib/jsse.jar:"
1264 "%/lib/jce.jar:"
1265 "%/lib/charsets.jar:"
1266 "%/lib/jfr.jar:"
1267 #ifdef __APPLE__
1268 "%/lib/JObjC.jar:"
1269 #endif
1270 "%/classes";
1271 char* sysclasspath = format_boot_path(classpath_format, home, home_len, fileSep, pathSep);
1272 if (sysclasspath == NULL) return false;
1273 Arguments::set_sysclasspath(sysclasspath);
1275 return true;
1276 }
1278 /*
1279 * Splits a path, based on its separator, the number of
1280 * elements is returned back in n.
1281 * It is the callers responsibility to:
1282 * a> check the value of n, and n may be 0.
1283 * b> ignore any empty path elements
1284 * c> free up the data.
1285 */
1286 char** os::split_path(const char* path, int* n) {
1287 *n = 0;
1288 if (path == NULL || strlen(path) == 0) {
1289 return NULL;
1290 }
1291 const char psepchar = *os::path_separator();
1292 char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal);
1293 if (inpath == NULL) {
1294 return NULL;
1295 }
1296 strcpy(inpath, path);
1297 int count = 1;
1298 char* p = strchr(inpath, psepchar);
1299 // Get a count of elements to allocate memory
1300 while (p != NULL) {
1301 count++;
1302 p++;
1303 p = strchr(p, psepchar);
1304 }
1305 char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count, mtInternal);
1306 if (opath == NULL) {
1307 return NULL;
1308 }
1310 // do the actual splitting
1311 p = inpath;
1312 for (int i = 0 ; i < count ; i++) {
1313 size_t len = strcspn(p, os::path_separator());
1314 if (len > JVM_MAXPATHLEN) {
1315 return NULL;
1316 }
1317 // allocate the string and add terminator storage
1318 char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
1319 if (s == NULL) {
1320 return NULL;
1321 }
1322 strncpy(s, p, len);
1323 s[len] = '\0';
1324 opath[i] = s;
1325 p += len + 1;
1326 }
1327 FREE_C_HEAP_ARRAY(char, inpath, mtInternal);
1328 *n = count;
1329 return opath;
1330 }
1332 void os::set_memory_serialize_page(address page) {
1333 int count = log2_intptr(sizeof(class JavaThread)) - log2_intptr(64);
1334 _mem_serialize_page = (volatile int32_t *)page;
1335 // We initialize the serialization page shift count here
1336 // We assume a cache line size of 64 bytes
1337 assert(SerializePageShiftCount == count,
1338 "thread size changed, fix SerializePageShiftCount constant");
1339 set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t)));
1340 }
1342 static volatile intptr_t SerializePageLock = 0;
1344 // This method is called from signal handler when SIGSEGV occurs while the current
1345 // thread tries to store to the "read-only" memory serialize page during state
1346 // transition.
1347 void os::block_on_serialize_page_trap() {
1348 if (TraceSafepoint) {
1349 tty->print_cr("Block until the serialize page permission restored");
1350 }
1351 // When VMThread is holding the SerializePageLock during modifying the
1352 // access permission of the memory serialize page, the following call
1353 // will block until the permission of that page is restored to rw.
1354 // Generally, it is unsafe to manipulate locks in signal handlers, but in
1355 // this case, it's OK as the signal is synchronous and we know precisely when
1356 // it can occur.
1357 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page");
1358 Thread::muxRelease(&SerializePageLock);
1359 }
1361 // Serialize all thread state variables
1362 void os::serialize_thread_states() {
1363 // On some platforms such as Solaris & Linux, the time duration of the page
1364 // permission restoration is observed to be much longer than expected due to
1365 // scheduler starvation problem etc. To avoid the long synchronization
1366 // time and expensive page trap spinning, 'SerializePageLock' is used to block
1367 // the mutator thread if such case is encountered. See bug 6546278 for details.
1368 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states");
1369 os::protect_memory((char *)os::get_memory_serialize_page(),
1370 os::vm_page_size(), MEM_PROT_READ);
1371 os::protect_memory((char *)os::get_memory_serialize_page(),
1372 os::vm_page_size(), MEM_PROT_RW);
1373 Thread::muxRelease(&SerializePageLock);
1374 }
1376 // Returns true if the current stack pointer is above the stack shadow
1377 // pages, false otherwise.
1379 bool os::stack_shadow_pages_available(Thread *thread, methodHandle method) {
1380 assert(StackRedPages > 0 && StackYellowPages > 0,"Sanity check");
1381 address sp = current_stack_pointer();
1382 // Check if we have StackShadowPages above the yellow zone. This parameter
1383 // is dependent on the depth of the maximum VM call stack possible from
1384 // the handler for stack overflow. 'instanceof' in the stack overflow
1385 // handler or a println uses at least 8k stack of VM and native code
1386 // respectively.
1387 const int framesize_in_bytes =
1388 Interpreter::size_top_interpreter_activation(method()) * wordSize;
1389 int reserved_area = ((StackShadowPages + StackRedPages + StackYellowPages)
1390 * vm_page_size()) + framesize_in_bytes;
1391 // The very lower end of the stack
1392 address stack_limit = thread->stack_base() - thread->stack_size();
1393 return (sp > (stack_limit + reserved_area));
1394 }
1396 size_t os::page_size_for_region(size_t region_min_size, size_t region_max_size,
1397 uint min_pages)
1398 {
1399 assert(min_pages > 0, "sanity");
1400 if (UseLargePages) {
1401 const size_t max_page_size = region_max_size / min_pages;
1403 for (unsigned int i = 0; _page_sizes[i] != 0; ++i) {
1404 const size_t sz = _page_sizes[i];
1405 const size_t mask = sz - 1;
1406 if ((region_min_size & mask) == 0 && (region_max_size & mask) == 0) {
1407 // The largest page size with no fragmentation.
1408 return sz;
1409 }
1411 if (sz <= max_page_size) {
1412 // The largest page size that satisfies the min_pages requirement.
1413 return sz;
1414 }
1415 }
1416 }
1418 return vm_page_size();
1419 }
1421 #ifndef PRODUCT
1422 void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count)
1423 {
1424 if (TracePageSizes) {
1425 tty->print("%s: ", str);
1426 for (int i = 0; i < count; ++i) {
1427 tty->print(" " SIZE_FORMAT, page_sizes[i]);
1428 }
1429 tty->cr();
1430 }
1431 }
1433 void os::trace_page_sizes(const char* str, const size_t region_min_size,
1434 const size_t region_max_size, const size_t page_size,
1435 const char* base, const size_t size)
1436 {
1437 if (TracePageSizes) {
1438 tty->print_cr("%s: min=" SIZE_FORMAT " max=" SIZE_FORMAT
1439 " pg_sz=" SIZE_FORMAT " base=" PTR_FORMAT
1440 " size=" SIZE_FORMAT,
1441 str, region_min_size, region_max_size,
1442 page_size, base, size);
1443 }
1444 }
1445 #endif // #ifndef PRODUCT
1447 // This is the working definition of a server class machine:
1448 // >= 2 physical CPU's and >=2GB of memory, with some fuzz
1449 // because the graphics memory (?) sometimes masks physical memory.
1450 // If you want to change the definition of a server class machine
1451 // on some OS or platform, e.g., >=4GB on Windohs platforms,
1452 // then you'll have to parameterize this method based on that state,
1453 // as was done for logical processors here, or replicate and
1454 // specialize this method for each platform. (Or fix os to have
1455 // some inheritance structure and use subclassing. Sigh.)
1456 // If you want some platform to always or never behave as a server
1457 // class machine, change the setting of AlwaysActAsServerClassMachine
1458 // and NeverActAsServerClassMachine in globals*.hpp.
1459 bool os::is_server_class_machine() {
1460 // First check for the early returns
1461 if (NeverActAsServerClassMachine) {
1462 return false;
1463 }
1464 if (AlwaysActAsServerClassMachine) {
1465 return true;
1466 }
1467 // Then actually look at the machine
1468 bool result = false;
1469 const unsigned int server_processors = 2;
1470 const julong server_memory = 2UL * G;
1471 // We seem not to get our full complement of memory.
1472 // We allow some part (1/8?) of the memory to be "missing",
1473 // based on the sizes of DIMMs, and maybe graphics cards.
1474 const julong missing_memory = 256UL * M;
1476 /* Is this a server class machine? */
1477 if ((os::active_processor_count() >= (int)server_processors) &&
1478 (os::physical_memory() >= (server_memory - missing_memory))) {
1479 const unsigned int logical_processors =
1480 VM_Version::logical_processors_per_package();
1481 if (logical_processors > 1) {
1482 const unsigned int physical_packages =
1483 os::active_processor_count() / logical_processors;
1484 if (physical_packages > server_processors) {
1485 result = true;
1486 }
1487 } else {
1488 result = true;
1489 }
1490 }
1491 return result;
1492 }
1494 void os::SuspendedThreadTask::run() {
1495 assert(Threads_lock->owned_by_self() || (_thread == VMThread::vm_thread()), "must have threads lock to call this");
1496 internal_do_task();
1497 _done = true;
1498 }
1500 bool os::create_stack_guard_pages(char* addr, size_t bytes) {
1501 return os::pd_create_stack_guard_pages(addr, bytes);
1502 }
1504 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint) {
1505 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1506 if (result != NULL) {
1507 MemTracker::record_virtual_memory_reserve((address)result, bytes, mtNone, CALLER_PC);
1508 }
1510 return result;
1511 }
1513 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint,
1514 MEMFLAGS flags) {
1515 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1516 if (result != NULL) {
1517 MemTracker::record_virtual_memory_reserve((address)result, bytes, mtNone, CALLER_PC);
1518 MemTracker::record_virtual_memory_type((address)result, flags);
1519 }
1521 return result;
1522 }
1524 char* os::attempt_reserve_memory_at(size_t bytes, char* addr) {
1525 char* result = pd_attempt_reserve_memory_at(bytes, addr);
1526 if (result != NULL) {
1527 MemTracker::record_virtual_memory_reserve((address)result, bytes, mtNone, CALLER_PC);
1528 }
1529 return result;
1530 }
1532 void os::split_reserved_memory(char *base, size_t size,
1533 size_t split, bool realloc) {
1534 pd_split_reserved_memory(base, size, split, realloc);
1535 }
1537 bool os::commit_memory(char* addr, size_t bytes, bool executable) {
1538 bool res = pd_commit_memory(addr, bytes, executable);
1539 if (res) {
1540 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1541 }
1542 return res;
1543 }
1545 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint,
1546 bool executable) {
1547 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable);
1548 if (res) {
1549 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1550 }
1551 return res;
1552 }
1554 void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable,
1555 const char* mesg) {
1556 pd_commit_memory_or_exit(addr, bytes, executable, mesg);
1557 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1558 }
1560 void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint,
1561 bool executable, const char* mesg) {
1562 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg);
1563 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1564 }
1566 bool os::uncommit_memory(char* addr, size_t bytes) {
1567 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_uncommit_tracker();
1568 bool res = pd_uncommit_memory(addr, bytes);
1569 if (res) {
1570 tkr.record((address)addr, bytes);
1571 } else {
1572 tkr.discard();
1573 }
1574 return res;
1575 }
1577 bool os::release_memory(char* addr, size_t bytes) {
1578 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
1579 bool res = pd_release_memory(addr, bytes);
1580 if (res) {
1581 tkr.record((address)addr, bytes);
1582 } else {
1583 tkr.discard();
1584 }
1585 return res;
1586 }
1589 char* os::map_memory(int fd, const char* file_name, size_t file_offset,
1590 char *addr, size_t bytes, bool read_only,
1591 bool allow_exec) {
1592 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec);
1593 if (result != NULL) {
1594 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, mtNone, CALLER_PC);
1595 }
1596 return result;
1597 }
1599 char* os::remap_memory(int fd, const char* file_name, size_t file_offset,
1600 char *addr, size_t bytes, bool read_only,
1601 bool allow_exec) {
1602 return pd_remap_memory(fd, file_name, file_offset, addr, bytes,
1603 read_only, allow_exec);
1604 }
1606 bool os::unmap_memory(char *addr, size_t bytes) {
1607 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
1608 bool result = pd_unmap_memory(addr, bytes);
1609 if (result) {
1610 tkr.record((address)addr, bytes);
1611 } else {
1612 tkr.discard();
1613 }
1614 return result;
1615 }
1617 void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) {
1618 pd_free_memory(addr, bytes, alignment_hint);
1619 }
1621 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
1622 pd_realign_memory(addr, bytes, alignment_hint);
1623 }
1625 #ifndef TARGET_OS_FAMILY_windows
1626 /* try to switch state from state "from" to state "to"
1627 * returns the state set after the method is complete
1628 */
1629 os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from,
1630 os::SuspendResume::State to)
1631 {
1632 os::SuspendResume::State result =
1633 (os::SuspendResume::State) Atomic::cmpxchg((jint) to, (jint *) &_state, (jint) from);
1634 if (result == from) {
1635 // success
1636 return to;
1637 }
1638 return result;
1639 }
1640 #endif