Mon, 20 Jun 2016 22:46:28 -0700
8155968: Update command line options
Reviewed-by: gthornbr, hseigel, mschoene
Contributed-by: gerard.ziemski@oracle.com
1 /*
2 * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
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 #ifdef ASSERT
36 #include "memory/guardedMemory.hpp"
37 #endif
38 #include "oops/oop.inline.hpp"
39 #include "prims/jvm.h"
40 #include "prims/jvm_misc.hpp"
41 #include "prims/privilegedStack.hpp"
42 #include "runtime/arguments.hpp"
43 #include "runtime/frame.inline.hpp"
44 #include "runtime/interfaceSupport.hpp"
45 #include "runtime/java.hpp"
46 #include "runtime/javaCalls.hpp"
47 #include "runtime/mutexLocker.hpp"
48 #include "runtime/os.hpp"
49 #include "runtime/stubRoutines.hpp"
50 #include "runtime/thread.inline.hpp"
51 #include "services/attachListener.hpp"
52 #include "services/nmtCommon.hpp"
53 #include "services/mallocTracker.hpp"
54 #include "services/memTracker.hpp"
55 #include "services/threadService.hpp"
56 #include "utilities/defaultStream.hpp"
57 #include "utilities/events.hpp"
58 #ifdef TARGET_OS_FAMILY_linux
59 # include "os_linux.inline.hpp"
60 #endif
61 #ifdef TARGET_OS_FAMILY_solaris
62 # include "os_solaris.inline.hpp"
63 #endif
64 #ifdef TARGET_OS_FAMILY_windows
65 # include "os_windows.inline.hpp"
66 #endif
67 #ifdef TARGET_OS_FAMILY_bsd
68 # include "os_bsd.inline.hpp"
69 #endif
71 # include <signal.h>
73 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
75 OSThread* os::_starting_thread = NULL;
76 address os::_polling_page = NULL;
77 volatile int32_t* os::_mem_serialize_page = NULL;
78 uintptr_t os::_serialize_page_mask = 0;
79 long os::_rand_seed = 1;
80 int os::_processor_count = 0;
81 size_t os::_page_sizes[os::page_sizes_max];
83 #ifndef PRODUCT
84 julong os::num_mallocs = 0; // # of calls to malloc/realloc
85 julong os::alloc_bytes = 0; // # of bytes allocated
86 julong os::num_frees = 0; // # of calls to free
87 julong os::free_bytes = 0; // # of bytes freed
88 #endif
90 static juint cur_malloc_words = 0; // current size for MallocMaxTestWords
92 void os_init_globals() {
93 // Called from init_globals().
94 // See Threads::create_vm() in thread.cpp, and init.cpp.
95 os::init_globals();
96 }
98 // Fill in buffer with current local time as an ISO-8601 string.
99 // E.g., yyyy-mm-ddThh:mm:ss-zzzz.
100 // Returns buffer, or NULL if it failed.
101 // This would mostly be a call to
102 // strftime(...., "%Y-%m-%d" "T" "%H:%M:%S" "%z", ....)
103 // except that on Windows the %z behaves badly, so we do it ourselves.
104 // Also, people wanted milliseconds on there,
105 // and strftime doesn't do milliseconds.
106 char* os::iso8601_time(char* buffer, size_t buffer_length) {
107 // Output will be of the form "YYYY-MM-DDThh:mm:ss.mmm+zzzz\0"
108 // 1 2
109 // 12345678901234567890123456789
110 static const char* iso8601_format =
111 "%04d-%02d-%02dT%02d:%02d:%02d.%03d%c%02d%02d";
112 static const size_t needed_buffer = 29;
114 // Sanity check the arguments
115 if (buffer == NULL) {
116 assert(false, "NULL buffer");
117 return NULL;
118 }
119 if (buffer_length < needed_buffer) {
120 assert(false, "buffer_length too small");
121 return NULL;
122 }
123 // Get the current time
124 jlong milliseconds_since_19700101 = javaTimeMillis();
125 const int milliseconds_per_microsecond = 1000;
126 const time_t seconds_since_19700101 =
127 milliseconds_since_19700101 / milliseconds_per_microsecond;
128 const int milliseconds_after_second =
129 milliseconds_since_19700101 % milliseconds_per_microsecond;
130 // Convert the time value to a tm and timezone variable
131 struct tm time_struct;
132 if (localtime_pd(&seconds_since_19700101, &time_struct) == NULL) {
133 assert(false, "Failed localtime_pd");
134 return NULL;
135 }
136 #if defined(_ALLBSD_SOURCE)
137 const time_t zone = (time_t) time_struct.tm_gmtoff;
138 #else
139 const time_t zone = timezone;
140 #endif
142 // If daylight savings time is in effect,
143 // we are 1 hour East of our time zone
144 const time_t seconds_per_minute = 60;
145 const time_t minutes_per_hour = 60;
146 const time_t seconds_per_hour = seconds_per_minute * minutes_per_hour;
147 time_t UTC_to_local = zone;
148 if (time_struct.tm_isdst > 0) {
149 UTC_to_local = UTC_to_local - seconds_per_hour;
150 }
151 // Compute the time zone offset.
152 // localtime_pd() sets timezone to the difference (in seconds)
153 // between UTC and and local time.
154 // ISO 8601 says we need the difference between local time and UTC,
155 // we change the sign of the localtime_pd() result.
156 const time_t local_to_UTC = -(UTC_to_local);
157 // Then we have to figure out if if we are ahead (+) or behind (-) UTC.
158 char sign_local_to_UTC = '+';
159 time_t abs_local_to_UTC = local_to_UTC;
160 if (local_to_UTC < 0) {
161 sign_local_to_UTC = '-';
162 abs_local_to_UTC = -(abs_local_to_UTC);
163 }
164 // Convert time zone offset seconds to hours and minutes.
165 const time_t zone_hours = (abs_local_to_UTC / seconds_per_hour);
166 const time_t zone_min =
167 ((abs_local_to_UTC % seconds_per_hour) / seconds_per_minute);
169 // Print an ISO 8601 date and time stamp into the buffer
170 const int year = 1900 + time_struct.tm_year;
171 const int month = 1 + time_struct.tm_mon;
172 const int printed = jio_snprintf(buffer, buffer_length, iso8601_format,
173 year,
174 month,
175 time_struct.tm_mday,
176 time_struct.tm_hour,
177 time_struct.tm_min,
178 time_struct.tm_sec,
179 milliseconds_after_second,
180 sign_local_to_UTC,
181 zone_hours,
182 zone_min);
183 if (printed == 0) {
184 assert(false, "Failed jio_printf");
185 return NULL;
186 }
187 return buffer;
188 }
190 OSReturn os::set_priority(Thread* thread, ThreadPriority p) {
191 #ifdef ASSERT
192 if (!(!thread->is_Java_thread() ||
193 Thread::current() == thread ||
194 Threads_lock->owned_by_self()
195 || thread->is_Compiler_thread()
196 )) {
197 assert(false, "possibility of dangling Thread pointer");
198 }
199 #endif
201 if (p >= MinPriority && p <= MaxPriority) {
202 int priority = java_to_os_priority[p];
203 return set_native_priority(thread, priority);
204 } else {
205 assert(false, "Should not happen");
206 return OS_ERR;
207 }
208 }
210 // The mapping from OS priority back to Java priority may be inexact because
211 // Java priorities can map M:1 with native priorities. If you want the definite
212 // Java priority then use JavaThread::java_priority()
213 OSReturn os::get_priority(const Thread* const thread, ThreadPriority& priority) {
214 int p;
215 int os_prio;
216 OSReturn ret = get_native_priority(thread, &os_prio);
217 if (ret != OS_OK) return ret;
219 if (java_to_os_priority[MaxPriority] > java_to_os_priority[MinPriority]) {
220 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] > os_prio; p--) ;
221 } else {
222 // niceness values are in reverse order
223 for (p = MaxPriority; p > MinPriority && java_to_os_priority[p] < os_prio; p--) ;
224 }
225 priority = (ThreadPriority)p;
226 return OS_OK;
227 }
230 // --------------------- sun.misc.Signal (optional) ---------------------
233 // SIGBREAK is sent by the keyboard to query the VM state
234 #ifndef SIGBREAK
235 #define SIGBREAK SIGQUIT
236 #endif
238 // sigexitnum_pd is a platform-specific special signal used for terminating the Signal thread.
241 static void signal_thread_entry(JavaThread* thread, TRAPS) {
242 os::set_priority(thread, NearMaxPriority);
243 while (true) {
244 int sig;
245 {
246 // FIXME : Currently we have not decieded what should be the status
247 // for this java thread blocked here. Once we decide about
248 // that we should fix this.
249 sig = os::signal_wait();
250 }
251 if (sig == os::sigexitnum_pd()) {
252 // Terminate the signal thread
253 return;
254 }
256 switch (sig) {
257 case SIGBREAK: {
258 // Check if the signal is a trigger to start the Attach Listener - in that
259 // case don't print stack traces.
260 if (!DisableAttachMechanism && AttachListener::is_init_trigger()) {
261 continue;
262 }
263 // Print stack traces
264 // Any SIGBREAK operations added here should make sure to flush
265 // the output stream (e.g. tty->flush()) after output. See 4803766.
266 // Each module also prints an extra carriage return after its output.
267 VM_PrintThreads op;
268 VMThread::execute(&op);
269 VM_PrintJNI jni_op;
270 VMThread::execute(&jni_op);
271 VM_FindDeadlocks op1(tty);
272 VMThread::execute(&op1);
273 Universe::print_heap_at_SIGBREAK();
274 if (PrintClassHistogram) {
275 VM_GC_HeapInspection op1(gclog_or_tty, true /* force full GC before heap inspection */);
276 VMThread::execute(&op1);
277 }
278 if (JvmtiExport::should_post_data_dump()) {
279 JvmtiExport::post_data_dump();
280 }
281 break;
282 }
283 default: {
284 // Dispatch the signal to java
285 HandleMark hm(THREAD);
286 Klass* k = SystemDictionary::resolve_or_null(vmSymbols::sun_misc_Signal(), THREAD);
287 KlassHandle klass (THREAD, k);
288 if (klass.not_null()) {
289 JavaValue result(T_VOID);
290 JavaCallArguments args;
291 args.push_int(sig);
292 JavaCalls::call_static(
293 &result,
294 klass,
295 vmSymbols::dispatch_name(),
296 vmSymbols::int_void_signature(),
297 &args,
298 THREAD
299 );
300 }
301 if (HAS_PENDING_EXCEPTION) {
302 // tty is initialized early so we don't expect it to be null, but
303 // if it is we can't risk doing an initialization that might
304 // trigger additional out-of-memory conditions
305 if (tty != NULL) {
306 char klass_name[256];
307 char tmp_sig_name[16];
308 const char* sig_name = "UNKNOWN";
309 InstanceKlass::cast(PENDING_EXCEPTION->klass())->
310 name()->as_klass_external_name(klass_name, 256);
311 if (os::exception_name(sig, tmp_sig_name, 16) != NULL)
312 sig_name = tmp_sig_name;
313 warning("Exception %s occurred dispatching signal %s to handler"
314 "- the VM may need to be forcibly terminated",
315 klass_name, sig_name );
316 }
317 CLEAR_PENDING_EXCEPTION;
318 }
319 }
320 }
321 }
322 }
324 void os::init_before_ergo() {
325 // We need to initialize large page support here because ergonomics takes some
326 // decisions depending on large page support and the calculated large page size.
327 large_page_init();
329 // VM version initialization identifies some characteristics of the
330 // the platform that are used during ergonomic decisions.
331 VM_Version::init_before_ergo();
332 }
334 void os::signal_init() {
335 if (!ReduceSignalUsage) {
336 // Setup JavaThread for processing signals
337 EXCEPTION_MARK;
338 Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(), true, CHECK);
339 instanceKlassHandle klass (THREAD, k);
340 instanceHandle thread_oop = klass->allocate_instance_handle(CHECK);
342 const char thread_name[] = "Signal Dispatcher";
343 Handle string = java_lang_String::create_from_str(thread_name, CHECK);
345 // Initialize thread_oop to put it into the system threadGroup
346 Handle thread_group (THREAD, Universe::system_thread_group());
347 JavaValue result(T_VOID);
348 JavaCalls::call_special(&result, thread_oop,
349 klass,
350 vmSymbols::object_initializer_name(),
351 vmSymbols::threadgroup_string_void_signature(),
352 thread_group,
353 string,
354 CHECK);
356 KlassHandle group(THREAD, SystemDictionary::ThreadGroup_klass());
357 JavaCalls::call_special(&result,
358 thread_group,
359 group,
360 vmSymbols::add_method_name(),
361 vmSymbols::thread_void_signature(),
362 thread_oop, // ARG 1
363 CHECK);
365 os::signal_init_pd();
367 { MutexLocker mu(Threads_lock);
368 JavaThread* signal_thread = new JavaThread(&signal_thread_entry);
370 // At this point it may be possible that no osthread was created for the
371 // JavaThread due to lack of memory. We would have to throw an exception
372 // in that case. However, since this must work and we do not allow
373 // exceptions anyway, check and abort if this fails.
374 if (signal_thread == NULL || signal_thread->osthread() == NULL) {
375 vm_exit_during_initialization("java.lang.OutOfMemoryError",
376 "unable to create new native thread");
377 }
379 java_lang_Thread::set_thread(thread_oop(), signal_thread);
380 java_lang_Thread::set_priority(thread_oop(), NearMaxPriority);
381 java_lang_Thread::set_daemon(thread_oop());
383 signal_thread->set_threadObj(thread_oop());
384 Threads::add(signal_thread);
385 Thread::start(signal_thread);
386 }
387 // Handle ^BREAK
388 os::signal(SIGBREAK, os::user_handler());
389 }
390 }
393 void os::terminate_signal_thread() {
394 if (!ReduceSignalUsage)
395 signal_notify(sigexitnum_pd());
396 }
399 // --------------------- loading libraries ---------------------
401 typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *);
402 extern struct JavaVM_ main_vm;
404 static void* _native_java_library = NULL;
406 void* os::native_java_library() {
407 if (_native_java_library == NULL) {
408 char buffer[JVM_MAXPATHLEN];
409 char ebuf[1024];
411 // Try to load verify dll first. In 1.3 java dll depends on it and is not
412 // always able to find it when the loading executable is outside the JDK.
413 // In order to keep working with 1.2 we ignore any loading errors.
414 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
415 "verify")) {
416 dll_load(buffer, ebuf, sizeof(ebuf));
417 }
419 // Load java dll
420 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
421 "java")) {
422 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf));
423 }
424 if (_native_java_library == NULL) {
425 vm_exit_during_initialization("Unable to load native library", ebuf);
426 }
428 #if defined(__OpenBSD__)
429 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so
430 // ignore errors
431 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
432 "net")) {
433 dll_load(buffer, ebuf, sizeof(ebuf));
434 }
435 #endif
436 }
437 static jboolean onLoaded = JNI_FALSE;
438 if (onLoaded) {
439 // We may have to wait to fire OnLoad until TLS is initialized.
440 if (ThreadLocalStorage::is_initialized()) {
441 // The JNI_OnLoad handling is normally done by method load in
442 // java.lang.ClassLoader$NativeLibrary, but the VM loads the base library
443 // explicitly so we have to check for JNI_OnLoad as well
444 const char *onLoadSymbols[] = JNI_ONLOAD_SYMBOLS;
445 JNI_OnLoad_t JNI_OnLoad = CAST_TO_FN_PTR(
446 JNI_OnLoad_t, dll_lookup(_native_java_library, onLoadSymbols[0]));
447 if (JNI_OnLoad != NULL) {
448 JavaThread* thread = JavaThread::current();
449 ThreadToNativeFromVM ttn(thread);
450 HandleMark hm(thread);
451 jint ver = (*JNI_OnLoad)(&main_vm, NULL);
452 onLoaded = JNI_TRUE;
453 if (!Threads::is_supported_jni_version_including_1_1(ver)) {
454 vm_exit_during_initialization("Unsupported JNI version");
455 }
456 }
457 }
458 }
459 return _native_java_library;
460 }
462 /*
463 * Support for finding Agent_On(Un)Load/Attach<_lib_name> if it exists.
464 * If check_lib == true then we are looking for an
465 * Agent_OnLoad_lib_name or Agent_OnAttach_lib_name function to determine if
466 * this library is statically linked into the image.
467 * If check_lib == false then we will look for the appropriate symbol in the
468 * executable if agent_lib->is_static_lib() == true or in the shared library
469 * referenced by 'handle'.
470 */
471 void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib,
472 const char *syms[], size_t syms_len) {
473 assert(agent_lib != NULL, "sanity check");
474 const char *lib_name;
475 void *handle = agent_lib->os_lib();
476 void *entryName = NULL;
477 char *agent_function_name;
478 size_t i;
480 // If checking then use the agent name otherwise test is_static_lib() to
481 // see how to process this lookup
482 lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL);
483 for (i = 0; i < syms_len; i++) {
484 agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path());
485 if (agent_function_name == NULL) {
486 break;
487 }
488 entryName = dll_lookup(handle, agent_function_name);
489 FREE_C_HEAP_ARRAY(char, agent_function_name, mtThread);
490 if (entryName != NULL) {
491 break;
492 }
493 }
494 return entryName;
495 }
497 // See if the passed in agent is statically linked into the VM image.
498 bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
499 size_t syms_len) {
500 void *ret;
501 void *proc_handle;
502 void *save_handle;
504 assert(agent_lib != NULL, "sanity check");
505 if (agent_lib->name() == NULL) {
506 return false;
507 }
508 proc_handle = get_default_process_handle();
509 // Check for Agent_OnLoad/Attach_lib_name function
510 save_handle = agent_lib->os_lib();
511 // We want to look in this process' symbol table.
512 agent_lib->set_os_lib(proc_handle);
513 ret = find_agent_function(agent_lib, true, syms, syms_len);
514 if (ret != NULL) {
515 // Found an entry point like Agent_OnLoad_lib_name so we have a static agent
516 agent_lib->set_valid();
517 agent_lib->set_static_lib(true);
518 return true;
519 }
520 agent_lib->set_os_lib(save_handle);
521 return false;
522 }
524 // --------------------- heap allocation utilities ---------------------
526 char *os::strdup(const char *str, MEMFLAGS flags) {
527 size_t size = strlen(str);
528 char *dup_str = (char *)malloc(size + 1, flags);
529 if (dup_str == NULL) return NULL;
530 strcpy(dup_str, str);
531 return dup_str;
532 }
536 #define paranoid 0 /* only set to 1 if you suspect checking code has bug */
538 #ifdef ASSERT
539 static void verify_memory(void* ptr) {
540 GuardedMemory guarded(ptr);
541 if (!guarded.verify_guards()) {
542 tty->print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees);
543 tty->print_cr("## memory stomp:");
544 guarded.print_on(tty);
545 fatal("memory stomping error");
546 }
547 }
548 #endif
550 //
551 // This function supports testing of the malloc out of memory
552 // condition without really running the system out of memory.
553 //
554 static u_char* testMalloc(size_t alloc_size) {
555 assert(MallocMaxTestWords > 0, "sanity check");
557 if ((cur_malloc_words + (alloc_size / BytesPerWord)) > MallocMaxTestWords) {
558 return NULL;
559 }
561 u_char* ptr = (u_char*)::malloc(alloc_size);
563 if (ptr != NULL) {
564 Atomic::add(((jint) (alloc_size / BytesPerWord)),
565 (volatile jint *) &cur_malloc_words);
566 }
567 return ptr;
568 }
570 void* os::malloc(size_t size, MEMFLAGS flags) {
571 return os::malloc(size, flags, CALLER_PC);
572 }
574 void* os::malloc(size_t size, MEMFLAGS memflags, const NativeCallStack& stack) {
575 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
576 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
578 #ifdef ASSERT
579 // checking for the WatcherThread and crash_protection first
580 // since os::malloc can be called when the libjvm.{dll,so} is
581 // first loaded and we don't have a thread yet.
582 // try to find the thread after we see that the watcher thread
583 // exists and has crash protection.
584 WatcherThread *wt = WatcherThread::watcher_thread();
585 if (wt != NULL && wt->has_crash_protection()) {
586 Thread* thread = ThreadLocalStorage::get_thread_slow();
587 if (thread == wt) {
588 assert(!wt->has_crash_protection(),
589 "Can't malloc with crash protection from WatcherThread");
590 }
591 }
592 #endif
594 if (size == 0) {
595 // return a valid pointer if size is zero
596 // if NULL is returned the calling functions assume out of memory.
597 size = 1;
598 }
600 // NMT support
601 NMT_TrackingLevel level = MemTracker::tracking_level();
602 size_t nmt_header_size = MemTracker::malloc_header_size(level);
604 #ifndef ASSERT
605 const size_t alloc_size = size + nmt_header_size;
606 #else
607 const size_t alloc_size = GuardedMemory::get_total_size(size + nmt_header_size);
608 if (size + nmt_header_size > alloc_size) { // Check for rollover.
609 return NULL;
610 }
611 #endif
613 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
615 u_char* ptr;
616 if (MallocMaxTestWords > 0) {
617 ptr = testMalloc(alloc_size);
618 } else {
619 ptr = (u_char*)::malloc(alloc_size);
620 }
622 #ifdef ASSERT
623 if (ptr == NULL) {
624 return NULL;
625 }
626 // Wrap memory with guard
627 GuardedMemory guarded(ptr, size + nmt_header_size);
628 ptr = guarded.get_user_ptr();
629 #endif
630 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) {
631 tty->print_cr("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr);
632 breakpoint();
633 }
634 debug_only(if (paranoid) verify_memory(ptr));
635 if (PrintMalloc && tty != NULL) {
636 tty->print_cr("os::malloc " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr);
637 }
639 // we do not track guard memory
640 return MemTracker::record_malloc((address)ptr, size, memflags, stack, level);
641 }
643 void* os::realloc(void *memblock, size_t size, MEMFLAGS flags) {
644 return os::realloc(memblock, size, flags, CALLER_PC);
645 }
647 void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, const NativeCallStack& stack) {
649 #ifndef ASSERT
650 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
651 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
652 // NMT support
653 void* membase = MemTracker::record_free(memblock);
654 NMT_TrackingLevel level = MemTracker::tracking_level();
655 size_t nmt_header_size = MemTracker::malloc_header_size(level);
656 void* ptr = ::realloc(membase, size + nmt_header_size);
657 return MemTracker::record_malloc(ptr, size, memflags, stack, level);
658 #else
659 if (memblock == NULL) {
660 return os::malloc(size, memflags, stack);
661 }
662 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
663 tty->print_cr("os::realloc caught " PTR_FORMAT, memblock);
664 breakpoint();
665 }
666 // NMT support
667 void* membase = MemTracker::malloc_base(memblock);
668 verify_memory(membase);
669 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
670 if (size == 0) {
671 return NULL;
672 }
673 // always move the block
674 void* ptr = os::malloc(size, memflags, stack);
675 if (PrintMalloc) {
676 tty->print_cr("os::remalloc " SIZE_FORMAT " bytes, " PTR_FORMAT " --> " PTR_FORMAT, size, memblock, ptr);
677 }
678 // Copy to new memory if malloc didn't fail
679 if ( ptr != NULL ) {
680 GuardedMemory guarded(MemTracker::malloc_base(memblock));
681 // Guard's user data contains NMT header
682 size_t memblock_size = guarded.get_user_size() - MemTracker::malloc_header_size(memblock);
683 memcpy(ptr, memblock, MIN2(size, memblock_size));
684 if (paranoid) verify_memory(MemTracker::malloc_base(ptr));
685 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) {
686 tty->print_cr("os::realloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr);
687 breakpoint();
688 }
689 os::free(memblock);
690 }
691 return ptr;
692 #endif
693 }
696 void os::free(void *memblock, MEMFLAGS memflags) {
697 NOT_PRODUCT(inc_stat_counter(&num_frees, 1));
698 #ifdef ASSERT
699 if (memblock == NULL) return;
700 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
701 if (tty != NULL) tty->print_cr("os::free caught " PTR_FORMAT, memblock);
702 breakpoint();
703 }
704 void* membase = MemTracker::record_free(memblock);
705 verify_memory(membase);
706 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
708 GuardedMemory guarded(membase);
709 size_t size = guarded.get_user_size();
710 inc_stat_counter(&free_bytes, size);
711 membase = guarded.release_for_freeing();
712 if (PrintMalloc && tty != NULL) {
713 fprintf(stderr, "os::free " SIZE_FORMAT " bytes --> " PTR_FORMAT "\n", size, (uintptr_t)membase);
714 }
715 ::free(membase);
716 #else
717 void* membase = MemTracker::record_free(memblock);
718 ::free(membase);
719 #endif
720 }
722 void os::init_random(long initval) {
723 _rand_seed = initval;
724 }
727 long os::random() {
728 /* standard, well-known linear congruential random generator with
729 * next_rand = (16807*seed) mod (2**31-1)
730 * see
731 * (1) "Random Number Generators: Good Ones Are Hard to Find",
732 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988),
733 * (2) "Two Fast Implementations of the 'Minimal Standard' Random
734 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88.
735 */
736 const long a = 16807;
737 const unsigned long m = 2147483647;
738 const long q = m / a; assert(q == 127773, "weird math");
739 const long r = m % a; assert(r == 2836, "weird math");
741 // compute az=2^31p+q
742 unsigned long lo = a * (long)(_rand_seed & 0xFFFF);
743 unsigned long hi = a * (long)((unsigned long)_rand_seed >> 16);
744 lo += (hi & 0x7FFF) << 16;
746 // if q overflowed, ignore the overflow and increment q
747 if (lo > m) {
748 lo &= m;
749 ++lo;
750 }
751 lo += hi >> 15;
753 // if (p+q) overflowed, ignore the overflow and increment (p+q)
754 if (lo > m) {
755 lo &= m;
756 ++lo;
757 }
758 return (_rand_seed = lo);
759 }
761 // The INITIALIZED state is distinguished from the SUSPENDED state because the
762 // conditions in which a thread is first started are different from those in which
763 // a suspension is resumed. These differences make it hard for us to apply the
764 // tougher checks when starting threads that we want to do when resuming them.
765 // However, when start_thread is called as a result of Thread.start, on a Java
766 // thread, the operation is synchronized on the Java Thread object. So there
767 // cannot be a race to start the thread and hence for the thread to exit while
768 // we are working on it. Non-Java threads that start Java threads either have
769 // to do so in a context in which races are impossible, or should do appropriate
770 // locking.
772 void os::start_thread(Thread* thread) {
773 // guard suspend/resume
774 MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag);
775 OSThread* osthread = thread->osthread();
776 osthread->set_state(RUNNABLE);
777 pd_start_thread(thread);
778 }
780 //---------------------------------------------------------------------------
781 // Helper functions for fatal error handler
783 void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) {
784 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking");
786 int cols = 0;
787 int cols_per_line = 0;
788 switch (unitsize) {
789 case 1: cols_per_line = 16; break;
790 case 2: cols_per_line = 8; break;
791 case 4: cols_per_line = 4; break;
792 case 8: cols_per_line = 2; break;
793 default: return;
794 }
796 address p = start;
797 st->print(PTR_FORMAT ": ", start);
798 while (p < end) {
799 switch (unitsize) {
800 case 1: st->print("%02x", *(u1*)p); break;
801 case 2: st->print("%04x", *(u2*)p); break;
802 case 4: st->print("%08x", *(u4*)p); break;
803 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break;
804 }
805 p += unitsize;
806 cols++;
807 if (cols >= cols_per_line && p < end) {
808 cols = 0;
809 st->cr();
810 st->print(PTR_FORMAT ": ", p);
811 } else {
812 st->print(" ");
813 }
814 }
815 st->cr();
816 }
818 void os::print_environment_variables(outputStream* st, const char** env_list,
819 char* buffer, int len) {
820 if (env_list) {
821 st->print_cr("Environment Variables:");
823 for (int i = 0; env_list[i] != NULL; i++) {
824 if (getenv(env_list[i], buffer, len)) {
825 st->print("%s", env_list[i]);
826 st->print("=");
827 st->print_cr("%s", buffer);
828 }
829 }
830 }
831 }
833 void os::print_cpu_info(outputStream* st) {
834 // cpu
835 st->print("CPU:");
836 st->print("total %d", os::processor_count());
837 // It's not safe to query number of active processors after crash
838 // st->print("(active %d)", os::active_processor_count());
839 st->print(" %s", VM_Version::cpu_features());
840 st->cr();
841 pd_print_cpu_info(st);
842 }
844 void os::print_date_and_time(outputStream *st) {
845 const int secs_per_day = 86400;
846 const int secs_per_hour = 3600;
847 const int secs_per_min = 60;
849 time_t tloc;
850 (void)time(&tloc);
851 st->print("time: %s", ctime(&tloc)); // ctime adds newline.
853 double t = os::elapsedTime();
854 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in
855 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int
856 // before printf. We lost some precision, but who cares?
857 int eltime = (int)t; // elapsed time in seconds
859 // print elapsed time in a human-readable format:
860 int eldays = eltime / secs_per_day;
861 int day_secs = eldays * secs_per_day;
862 int elhours = (eltime - day_secs) / secs_per_hour;
863 int hour_secs = elhours * secs_per_hour;
864 int elmins = (eltime - day_secs - hour_secs) / secs_per_min;
865 int minute_secs = elmins * secs_per_min;
866 int elsecs = (eltime - day_secs - hour_secs - minute_secs);
867 st->print_cr("elapsed time: %d seconds (%dd %dh %dm %ds)", eltime, eldays, elhours, elmins, elsecs);
868 }
870 // moved from debug.cpp (used to be find()) but still called from there
871 // The verbose parameter is only set by the debug code in one case
872 void os::print_location(outputStream* st, intptr_t x, bool verbose) {
873 address addr = (address)x;
874 CodeBlob* b = CodeCache::find_blob_unsafe(addr);
875 if (b != NULL) {
876 if (b->is_buffer_blob()) {
877 // the interpreter is generated into a buffer blob
878 InterpreterCodelet* i = Interpreter::codelet_containing(addr);
879 if (i != NULL) {
880 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an Interpreter codelet", addr, (int)(addr - i->code_begin()));
881 i->print_on(st);
882 return;
883 }
884 if (Interpreter::contains(addr)) {
885 st->print_cr(INTPTR_FORMAT " is pointing into interpreter code"
886 " (not bytecode specific)", addr);
887 return;
888 }
889 //
890 if (AdapterHandlerLibrary::contains(b)) {
891 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an AdapterHandler", addr, (int)(addr - b->code_begin()));
892 AdapterHandlerLibrary::print_handler_on(st, b);
893 }
894 // the stubroutines are generated into a buffer blob
895 StubCodeDesc* d = StubCodeDesc::desc_for(addr);
896 if (d != NULL) {
897 st->print_cr(INTPTR_FORMAT " is at begin+%d in a stub", addr, (int)(addr - d->begin()));
898 d->print_on(st);
899 st->cr();
900 return;
901 }
902 if (StubRoutines::contains(addr)) {
903 st->print_cr(INTPTR_FORMAT " is pointing to an (unnamed) "
904 "stub routine", addr);
905 return;
906 }
907 // the InlineCacheBuffer is using stubs generated into a buffer blob
908 if (InlineCacheBuffer::contains(addr)) {
909 st->print_cr(INTPTR_FORMAT " is pointing into InlineCacheBuffer", addr);
910 return;
911 }
912 VtableStub* v = VtableStubs::stub_containing(addr);
913 if (v != NULL) {
914 st->print_cr(INTPTR_FORMAT " is at entry_point+%d in a vtable stub", addr, (int)(addr - v->entry_point()));
915 v->print_on(st);
916 st->cr();
917 return;
918 }
919 }
920 nmethod* nm = b->as_nmethod_or_null();
921 if (nm != NULL) {
922 ResourceMark rm;
923 st->print(INTPTR_FORMAT " is at entry_point+%d in (nmethod*)" INTPTR_FORMAT,
924 addr, (int)(addr - nm->entry_point()), nm);
925 if (verbose) {
926 st->print(" for ");
927 nm->method()->print_value_on(st);
928 }
929 st->cr();
930 nm->print_nmethod(verbose);
931 return;
932 }
933 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in ", addr, (int)(addr - b->code_begin()));
934 b->print_on(st);
935 return;
936 }
938 if (Universe::heap()->is_in(addr)) {
939 HeapWord* p = Universe::heap()->block_start(addr);
940 bool print = false;
941 // If we couldn't find it it just may mean that heap wasn't parseable
942 // See if we were just given an oop directly
943 if (p != NULL && Universe::heap()->block_is_obj(p)) {
944 print = true;
945 } else if (p == NULL && ((oopDesc*)addr)->is_oop()) {
946 p = (HeapWord*) addr;
947 print = true;
948 }
949 if (print) {
950 if (p == (HeapWord*) addr) {
951 st->print_cr(INTPTR_FORMAT " is an oop", addr);
952 } else {
953 st->print_cr(INTPTR_FORMAT " is pointing into object: " INTPTR_FORMAT, addr, p);
954 }
955 oop(p)->print_on(st);
956 return;
957 }
958 } else {
959 if (Universe::heap()->is_in_reserved(addr)) {
960 st->print_cr(INTPTR_FORMAT " is an unallocated location "
961 "in the heap", addr);
962 return;
963 }
964 }
965 if (JNIHandles::is_global_handle((jobject) addr)) {
966 st->print_cr(INTPTR_FORMAT " is a global jni handle", addr);
967 return;
968 }
969 if (JNIHandles::is_weak_global_handle((jobject) addr)) {
970 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", addr);
971 return;
972 }
973 #ifndef PRODUCT
974 // we don't keep the block list in product mode
975 if (JNIHandleBlock::any_contains((jobject) addr)) {
976 st->print_cr(INTPTR_FORMAT " is a local jni handle", addr);
977 return;
978 }
979 #endif
981 for(JavaThread *thread = Threads::first(); thread; thread = thread->next()) {
982 // Check for privilege stack
983 if (thread->privileged_stack_top() != NULL &&
984 thread->privileged_stack_top()->contains(addr)) {
985 st->print_cr(INTPTR_FORMAT " is pointing into the privilege stack "
986 "for thread: " INTPTR_FORMAT, addr, thread);
987 if (verbose) thread->print_on(st);
988 return;
989 }
990 // If the addr is a java thread print information about that.
991 if (addr == (address)thread) {
992 if (verbose) {
993 thread->print_on(st);
994 } else {
995 st->print_cr(INTPTR_FORMAT " is a thread", addr);
996 }
997 return;
998 }
999 // If the addr is in the stack region for this thread then report that
1000 // and print thread info
1001 if (thread->stack_base() >= addr &&
1002 addr > (thread->stack_base() - thread->stack_size())) {
1003 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: "
1004 INTPTR_FORMAT, addr, thread);
1005 if (verbose) thread->print_on(st);
1006 return;
1007 }
1009 }
1011 // Check if in metaspace and print types that have vptrs (only method now)
1012 if (Metaspace::contains(addr)) {
1013 if (Method::has_method_vptr((const void*)addr)) {
1014 ((Method*)addr)->print_value_on(st);
1015 st->cr();
1016 } else {
1017 // Use addr->print() from the debugger instead (not here)
1018 st->print_cr(INTPTR_FORMAT " is pointing into metadata", addr);
1019 }
1020 return;
1021 }
1023 // Try an OS specific find
1024 if (os::find(addr, st)) {
1025 return;
1026 }
1028 st->print_cr(INTPTR_FORMAT " is an unknown value", addr);
1029 }
1031 // Looks like all platforms except IA64 can use the same function to check
1032 // if C stack is walkable beyond current frame. The check for fp() is not
1033 // necessary on Sparc, but it's harmless.
1034 bool os::is_first_C_frame(frame* fr) {
1035 #if (defined(IA64) && !defined(AIX)) && !defined(_WIN32)
1036 // On IA64 we have to check if the callers bsp is still valid
1037 // (i.e. within the register stack bounds).
1038 // Notice: this only works for threads created by the VM and only if
1039 // we walk the current stack!!! If we want to be able to walk
1040 // arbitrary other threads, we'll have to somehow store the thread
1041 // object in the frame.
1042 Thread *thread = Thread::current();
1043 if ((address)fr->fp() <=
1044 thread->register_stack_base() HPUX_ONLY(+ 0x0) LINUX_ONLY(+ 0x50)) {
1045 // This check is a little hacky, because on Linux the first C
1046 // frame's ('start_thread') register stack frame starts at
1047 // "register_stack_base + 0x48" while on HPUX, the first C frame's
1048 // ('__pthread_bound_body') register stack frame seems to really
1049 // start at "register_stack_base".
1050 return true;
1051 } else {
1052 return false;
1053 }
1054 #elif defined(IA64) && defined(_WIN32)
1055 return true;
1056 #else
1057 // Load up sp, fp, sender sp and sender fp, check for reasonable values.
1058 // Check usp first, because if that's bad the other accessors may fault
1059 // on some architectures. Ditto ufp second, etc.
1060 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1);
1061 // sp on amd can be 32 bit aligned.
1062 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1);
1064 uintptr_t usp = (uintptr_t)fr->sp();
1065 if ((usp & sp_align_mask) != 0) return true;
1067 uintptr_t ufp = (uintptr_t)fr->fp();
1068 if ((ufp & fp_align_mask) != 0) return true;
1070 uintptr_t old_sp = (uintptr_t)fr->sender_sp();
1071 if ((old_sp & sp_align_mask) != 0) return true;
1072 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true;
1074 uintptr_t old_fp = (uintptr_t)fr->link();
1075 if ((old_fp & fp_align_mask) != 0) return true;
1076 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true;
1078 // stack grows downwards; if old_fp is below current fp or if the stack
1079 // frame is too large, either the stack is corrupted or fp is not saved
1080 // on stack (i.e. on x86, ebp may be used as general register). The stack
1081 // is not walkable beyond current frame.
1082 if (old_fp < ufp) return true;
1083 if (old_fp - ufp > 64 * K) return true;
1085 return false;
1086 #endif
1087 }
1089 #ifdef ASSERT
1090 extern "C" void test_random() {
1091 const double m = 2147483647;
1092 double mean = 0.0, variance = 0.0, t;
1093 long reps = 10000;
1094 unsigned long seed = 1;
1096 tty->print_cr("seed %ld for %ld repeats...", seed, reps);
1097 os::init_random(seed);
1098 long num;
1099 for (int k = 0; k < reps; k++) {
1100 num = os::random();
1101 double u = (double)num / m;
1102 assert(u >= 0.0 && u <= 1.0, "bad random number!");
1104 // calculate mean and variance of the random sequence
1105 mean += u;
1106 variance += (u*u);
1107 }
1108 mean /= reps;
1109 variance /= (reps - 1);
1111 assert(num == 1043618065, "bad seed");
1112 tty->print_cr("mean of the 1st 10000 numbers: %f", mean);
1113 tty->print_cr("variance of the 1st 10000 numbers: %f", variance);
1114 const double eps = 0.0001;
1115 t = fabsd(mean - 0.5018);
1116 assert(t < eps, "bad mean");
1117 t = (variance - 0.3355) < 0.0 ? -(variance - 0.3355) : variance - 0.3355;
1118 assert(t < eps, "bad variance");
1119 }
1120 #endif
1123 // Set up the boot classpath.
1125 char* os::format_boot_path(const char* format_string,
1126 const char* home,
1127 int home_len,
1128 char fileSep,
1129 char pathSep) {
1130 assert((fileSep == '/' && pathSep == ':') ||
1131 (fileSep == '\\' && pathSep == ';'), "unexpected seperator chars");
1133 // Scan the format string to determine the length of the actual
1134 // boot classpath, and handle platform dependencies as well.
1135 int formatted_path_len = 0;
1136 const char* p;
1137 for (p = format_string; *p != 0; ++p) {
1138 if (*p == '%') formatted_path_len += home_len - 1;
1139 ++formatted_path_len;
1140 }
1142 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal);
1143 if (formatted_path == NULL) {
1144 return NULL;
1145 }
1147 // Create boot classpath from format, substituting separator chars and
1148 // java home directory.
1149 char* q = formatted_path;
1150 for (p = format_string; *p != 0; ++p) {
1151 switch (*p) {
1152 case '%':
1153 strcpy(q, home);
1154 q += home_len;
1155 break;
1156 case '/':
1157 *q++ = fileSep;
1158 break;
1159 case ':':
1160 *q++ = pathSep;
1161 break;
1162 default:
1163 *q++ = *p;
1164 }
1165 }
1166 *q = '\0';
1168 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched");
1169 return formatted_path;
1170 }
1173 bool os::set_boot_path(char fileSep, char pathSep) {
1174 const char* home = Arguments::get_java_home();
1175 int home_len = (int)strlen(home);
1177 static const char* meta_index_dir_format = "%/lib/";
1178 static const char* meta_index_format = "%/lib/meta-index";
1179 char* meta_index = format_boot_path(meta_index_format, home, home_len, fileSep, pathSep);
1180 if (meta_index == NULL) return false;
1181 char* meta_index_dir = format_boot_path(meta_index_dir_format, home, home_len, fileSep, pathSep);
1182 if (meta_index_dir == NULL) return false;
1183 Arguments::set_meta_index_path(meta_index, meta_index_dir);
1185 // Any modification to the JAR-file list, for the boot classpath must be
1186 // aligned with install/install/make/common/Pack.gmk. Note: boot class
1187 // path class JARs, are stripped for StackMapTable to reduce download size.
1188 static const char classpath_format[] =
1189 "%/lib/resources.jar:"
1190 "%/lib/rt.jar:"
1191 "%/lib/sunrsasign.jar:"
1192 "%/lib/jsse.jar:"
1193 "%/lib/jce.jar:"
1194 "%/lib/charsets.jar:"
1195 "%/lib/jfr.jar:"
1196 "%/classes";
1197 char* sysclasspath = format_boot_path(classpath_format, home, home_len, fileSep, pathSep);
1198 if (sysclasspath == NULL) return false;
1199 Arguments::set_sysclasspath(sysclasspath);
1201 return true;
1202 }
1204 /*
1205 * Splits a path, based on its separator, the number of
1206 * elements is returned back in n.
1207 * It is the callers responsibility to:
1208 * a> check the value of n, and n may be 0.
1209 * b> ignore any empty path elements
1210 * c> free up the data.
1211 */
1212 char** os::split_path(const char* path, int* n) {
1213 *n = 0;
1214 if (path == NULL || strlen(path) == 0) {
1215 return NULL;
1216 }
1217 const char psepchar = *os::path_separator();
1218 char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal);
1219 if (inpath == NULL) {
1220 return NULL;
1221 }
1222 strcpy(inpath, path);
1223 int count = 1;
1224 char* p = strchr(inpath, psepchar);
1225 // Get a count of elements to allocate memory
1226 while (p != NULL) {
1227 count++;
1228 p++;
1229 p = strchr(p, psepchar);
1230 }
1231 char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count, mtInternal);
1232 if (opath == NULL) {
1233 return NULL;
1234 }
1236 // do the actual splitting
1237 p = inpath;
1238 for (int i = 0 ; i < count ; i++) {
1239 size_t len = strcspn(p, os::path_separator());
1240 if (len > JVM_MAXPATHLEN) {
1241 return NULL;
1242 }
1243 // allocate the string and add terminator storage
1244 char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
1245 if (s == NULL) {
1246 return NULL;
1247 }
1248 strncpy(s, p, len);
1249 s[len] = '\0';
1250 opath[i] = s;
1251 p += len + 1;
1252 }
1253 FREE_C_HEAP_ARRAY(char, inpath, mtInternal);
1254 *n = count;
1255 return opath;
1256 }
1258 void os::set_memory_serialize_page(address page) {
1259 int count = log2_intptr(sizeof(class JavaThread)) - log2_intptr(64);
1260 _mem_serialize_page = (volatile int32_t *)page;
1261 // We initialize the serialization page shift count here
1262 // We assume a cache line size of 64 bytes
1263 assert(SerializePageShiftCount == count,
1264 "thread size changed, fix SerializePageShiftCount constant");
1265 set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t)));
1266 }
1268 static volatile intptr_t SerializePageLock = 0;
1270 // This method is called from signal handler when SIGSEGV occurs while the current
1271 // thread tries to store to the "read-only" memory serialize page during state
1272 // transition.
1273 void os::block_on_serialize_page_trap() {
1274 if (TraceSafepoint) {
1275 tty->print_cr("Block until the serialize page permission restored");
1276 }
1277 // When VMThread is holding the SerializePageLock during modifying the
1278 // access permission of the memory serialize page, the following call
1279 // will block until the permission of that page is restored to rw.
1280 // Generally, it is unsafe to manipulate locks in signal handlers, but in
1281 // this case, it's OK as the signal is synchronous and we know precisely when
1282 // it can occur.
1283 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page");
1284 Thread::muxRelease(&SerializePageLock);
1285 }
1287 // Serialize all thread state variables
1288 void os::serialize_thread_states() {
1289 // On some platforms such as Solaris & Linux, the time duration of the page
1290 // permission restoration is observed to be much longer than expected due to
1291 // scheduler starvation problem etc. To avoid the long synchronization
1292 // time and expensive page trap spinning, 'SerializePageLock' is used to block
1293 // the mutator thread if such case is encountered. See bug 6546278 for details.
1294 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states");
1295 os::protect_memory((char *)os::get_memory_serialize_page(),
1296 os::vm_page_size(), MEM_PROT_READ);
1297 os::protect_memory((char *)os::get_memory_serialize_page(),
1298 os::vm_page_size(), MEM_PROT_RW);
1299 Thread::muxRelease(&SerializePageLock);
1300 }
1302 // Returns true if the current stack pointer is above the stack shadow
1303 // pages, false otherwise.
1305 bool os::stack_shadow_pages_available(Thread *thread, methodHandle method) {
1306 assert(StackRedPages > 0 && StackYellowPages > 0,"Sanity check");
1307 address sp = current_stack_pointer();
1308 // Check if we have StackShadowPages above the yellow zone. This parameter
1309 // is dependent on the depth of the maximum VM call stack possible from
1310 // the handler for stack overflow. 'instanceof' in the stack overflow
1311 // handler or a println uses at least 8k stack of VM and native code
1312 // respectively.
1313 const int framesize_in_bytes =
1314 Interpreter::size_top_interpreter_activation(method()) * wordSize;
1315 int reserved_area = ((StackShadowPages + StackRedPages + StackYellowPages)
1316 * vm_page_size()) + framesize_in_bytes;
1317 // The very lower end of the stack
1318 address stack_limit = thread->stack_base() - thread->stack_size();
1319 return (sp > (stack_limit + reserved_area));
1320 }
1322 size_t os::page_size_for_region(size_t region_size, size_t min_pages, bool must_be_aligned) {
1323 assert(min_pages > 0, "sanity");
1324 if (UseLargePages) {
1325 const size_t max_page_size = region_size / min_pages;
1327 for (size_t i = 0; _page_sizes[i] != 0; ++i) {
1328 const size_t page_size = _page_sizes[i];
1329 if (page_size <= max_page_size) {
1330 if (!must_be_aligned || is_size_aligned(region_size, page_size)) {
1331 return page_size;
1332 }
1333 }
1334 }
1335 }
1337 return vm_page_size();
1338 }
1340 size_t os::page_size_for_region_aligned(size_t region_size, size_t min_pages) {
1341 return page_size_for_region(region_size, min_pages, true);
1342 }
1344 size_t os::page_size_for_region_unaligned(size_t region_size, size_t min_pages) {
1345 return page_size_for_region(region_size, min_pages, false);
1346 }
1348 #ifndef PRODUCT
1349 void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count)
1350 {
1351 if (TracePageSizes) {
1352 tty->print("%s: ", str);
1353 for (int i = 0; i < count; ++i) {
1354 tty->print(" " SIZE_FORMAT, page_sizes[i]);
1355 }
1356 tty->cr();
1357 }
1358 }
1360 void os::trace_page_sizes(const char* str, const size_t region_min_size,
1361 const size_t region_max_size, const size_t page_size,
1362 const char* base, const size_t size)
1363 {
1364 if (TracePageSizes) {
1365 tty->print_cr("%s: min=" SIZE_FORMAT " max=" SIZE_FORMAT
1366 " pg_sz=" SIZE_FORMAT " base=" PTR_FORMAT
1367 " size=" SIZE_FORMAT,
1368 str, region_min_size, region_max_size,
1369 page_size, base, size);
1370 }
1371 }
1372 #endif // #ifndef PRODUCT
1374 // This is the working definition of a server class machine:
1375 // >= 2 physical CPU's and >=2GB of memory, with some fuzz
1376 // because the graphics memory (?) sometimes masks physical memory.
1377 // If you want to change the definition of a server class machine
1378 // on some OS or platform, e.g., >=4GB on Windohs platforms,
1379 // then you'll have to parameterize this method based on that state,
1380 // as was done for logical processors here, or replicate and
1381 // specialize this method for each platform. (Or fix os to have
1382 // some inheritance structure and use subclassing. Sigh.)
1383 // If you want some platform to always or never behave as a server
1384 // class machine, change the setting of AlwaysActAsServerClassMachine
1385 // and NeverActAsServerClassMachine in globals*.hpp.
1386 bool os::is_server_class_machine() {
1387 // First check for the early returns
1388 if (NeverActAsServerClassMachine) {
1389 return false;
1390 }
1391 if (AlwaysActAsServerClassMachine) {
1392 return true;
1393 }
1394 // Then actually look at the machine
1395 bool result = false;
1396 const unsigned int server_processors = 2;
1397 const julong server_memory = 2UL * G;
1398 // We seem not to get our full complement of memory.
1399 // We allow some part (1/8?) of the memory to be "missing",
1400 // based on the sizes of DIMMs, and maybe graphics cards.
1401 const julong missing_memory = 256UL * M;
1403 /* Is this a server class machine? */
1404 if ((os::active_processor_count() >= (int)server_processors) &&
1405 (os::physical_memory() >= (server_memory - missing_memory))) {
1406 const unsigned int logical_processors =
1407 VM_Version::logical_processors_per_package();
1408 if (logical_processors > 1) {
1409 const unsigned int physical_packages =
1410 os::active_processor_count() / logical_processors;
1411 if (physical_packages > server_processors) {
1412 result = true;
1413 }
1414 } else {
1415 result = true;
1416 }
1417 }
1418 return result;
1419 }
1421 void os::SuspendedThreadTask::run() {
1422 assert(Threads_lock->owned_by_self() || (_thread == VMThread::vm_thread()), "must have threads lock to call this");
1423 internal_do_task();
1424 _done = true;
1425 }
1427 bool os::create_stack_guard_pages(char* addr, size_t bytes) {
1428 return os::pd_create_stack_guard_pages(addr, bytes);
1429 }
1431 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint) {
1432 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1433 if (result != NULL) {
1434 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1435 }
1437 return result;
1438 }
1440 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint,
1441 MEMFLAGS flags) {
1442 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1443 if (result != NULL) {
1444 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1445 MemTracker::record_virtual_memory_type((address)result, flags);
1446 }
1448 return result;
1449 }
1451 char* os::attempt_reserve_memory_at(size_t bytes, char* addr) {
1452 char* result = pd_attempt_reserve_memory_at(bytes, addr);
1453 if (result != NULL) {
1454 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1455 }
1456 return result;
1457 }
1459 void os::split_reserved_memory(char *base, size_t size,
1460 size_t split, bool realloc) {
1461 pd_split_reserved_memory(base, size, split, realloc);
1462 }
1464 bool os::commit_memory(char* addr, size_t bytes, bool executable) {
1465 bool res = pd_commit_memory(addr, bytes, executable);
1466 if (res) {
1467 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1468 }
1469 return res;
1470 }
1472 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint,
1473 bool executable) {
1474 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable);
1475 if (res) {
1476 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1477 }
1478 return res;
1479 }
1481 void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable,
1482 const char* mesg) {
1483 pd_commit_memory_or_exit(addr, bytes, executable, mesg);
1484 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1485 }
1487 void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint,
1488 bool executable, const char* mesg) {
1489 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg);
1490 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1491 }
1493 bool os::uncommit_memory(char* addr, size_t bytes) {
1494 bool res;
1495 if (MemTracker::tracking_level() > NMT_minimal) {
1496 Tracker tkr = MemTracker::get_virtual_memory_uncommit_tracker();
1497 res = pd_uncommit_memory(addr, bytes);
1498 if (res) {
1499 tkr.record((address)addr, bytes);
1500 }
1501 } else {
1502 res = pd_uncommit_memory(addr, bytes);
1503 }
1504 return res;
1505 }
1507 bool os::release_memory(char* addr, size_t bytes) {
1508 bool res;
1509 if (MemTracker::tracking_level() > NMT_minimal) {
1510 Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
1511 res = pd_release_memory(addr, bytes);
1512 if (res) {
1513 tkr.record((address)addr, bytes);
1514 }
1515 } else {
1516 res = pd_release_memory(addr, bytes);
1517 }
1518 return res;
1519 }
1521 void os::pretouch_memory(char* start, char* end) {
1522 for (volatile char *p = start; p < end; p += os::vm_page_size()) {
1523 *p = 0;
1524 }
1525 }
1527 char* os::map_memory(int fd, const char* file_name, size_t file_offset,
1528 char *addr, size_t bytes, bool read_only,
1529 bool allow_exec) {
1530 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec);
1531 if (result != NULL) {
1532 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, CALLER_PC);
1533 }
1534 return result;
1535 }
1537 char* os::remap_memory(int fd, const char* file_name, size_t file_offset,
1538 char *addr, size_t bytes, bool read_only,
1539 bool allow_exec) {
1540 return pd_remap_memory(fd, file_name, file_offset, addr, bytes,
1541 read_only, allow_exec);
1542 }
1544 bool os::unmap_memory(char *addr, size_t bytes) {
1545 bool result;
1546 if (MemTracker::tracking_level() > NMT_minimal) {
1547 Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
1548 result = pd_unmap_memory(addr, bytes);
1549 if (result) {
1550 tkr.record((address)addr, bytes);
1551 }
1552 } else {
1553 result = pd_unmap_memory(addr, bytes);
1554 }
1555 return result;
1556 }
1558 void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) {
1559 pd_free_memory(addr, bytes, alignment_hint);
1560 }
1562 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
1563 pd_realign_memory(addr, bytes, alignment_hint);
1564 }
1566 #ifndef TARGET_OS_FAMILY_windows
1567 /* try to switch state from state "from" to state "to"
1568 * returns the state set after the method is complete
1569 */
1570 os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from,
1571 os::SuspendResume::State to)
1572 {
1573 os::SuspendResume::State result =
1574 (os::SuspendResume::State) Atomic::cmpxchg((jint) to, (jint *) &_state, (jint) from);
1575 if (result == from) {
1576 // success
1577 return to;
1578 }
1579 return result;
1580 }
1581 #endif
1583 /////////////// Unit tests ///////////////
1585 #ifndef PRODUCT
1587 #define assert_eq(a,b) assert(a == b, err_msg(SIZE_FORMAT " != " SIZE_FORMAT, a, b))
1589 class TestOS : AllStatic {
1590 static size_t small_page_size() {
1591 return os::vm_page_size();
1592 }
1594 static size_t large_page_size() {
1595 const size_t large_page_size_example = 4 * M;
1596 return os::page_size_for_region_aligned(large_page_size_example, 1);
1597 }
1599 static void test_page_size_for_region_aligned() {
1600 if (UseLargePages) {
1601 const size_t small_page = small_page_size();
1602 const size_t large_page = large_page_size();
1604 if (large_page > small_page) {
1605 size_t num_small_pages_in_large = large_page / small_page;
1606 size_t page = os::page_size_for_region_aligned(large_page, num_small_pages_in_large);
1608 assert_eq(page, small_page);
1609 }
1610 }
1611 }
1613 static void test_page_size_for_region_alignment() {
1614 if (UseLargePages) {
1615 const size_t small_page = small_page_size();
1616 const size_t large_page = large_page_size();
1617 if (large_page > small_page) {
1618 const size_t unaligned_region = large_page + 17;
1619 size_t page = os::page_size_for_region_aligned(unaligned_region, 1);
1620 assert_eq(page, small_page);
1622 const size_t num_pages = 5;
1623 const size_t aligned_region = large_page * num_pages;
1624 page = os::page_size_for_region_aligned(aligned_region, num_pages);
1625 assert_eq(page, large_page);
1626 }
1627 }
1628 }
1630 static void test_page_size_for_region_unaligned() {
1631 if (UseLargePages) {
1632 // Given exact page size, should return that page size.
1633 for (size_t i = 0; os::_page_sizes[i] != 0; i++) {
1634 size_t expected = os::_page_sizes[i];
1635 size_t actual = os::page_size_for_region_unaligned(expected, 1);
1636 assert_eq(expected, actual);
1637 }
1639 // Given slightly larger size than a page size, return the page size.
1640 for (size_t i = 0; os::_page_sizes[i] != 0; i++) {
1641 size_t expected = os::_page_sizes[i];
1642 size_t actual = os::page_size_for_region_unaligned(expected + 17, 1);
1643 assert_eq(expected, actual);
1644 }
1646 // Given a slightly smaller size than a page size,
1647 // return the next smaller page size.
1648 if (os::_page_sizes[1] > os::_page_sizes[0]) {
1649 size_t expected = os::_page_sizes[0];
1650 size_t actual = os::page_size_for_region_unaligned(os::_page_sizes[1] - 17, 1);
1651 assert_eq(actual, expected);
1652 }
1654 // Return small page size for values less than a small page.
1655 size_t small_page = small_page_size();
1656 size_t actual = os::page_size_for_region_unaligned(small_page - 17, 1);
1657 assert_eq(small_page, actual);
1658 }
1659 }
1661 public:
1662 static void run_tests() {
1663 test_page_size_for_region_aligned();
1664 test_page_size_for_region_alignment();
1665 test_page_size_for_region_unaligned();
1666 }
1667 };
1669 void TestOS_test() {
1670 TestOS::run_tests();
1671 }
1673 #endif // PRODUCT