Wed, 11 Sep 2013 20:03:34 -0400
8024007: Misc. cleanup of static agent code
Summary: Minor cleanup of static agent code from 8014135
Reviewed-by: dcubed, sspitsyn
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 }
318 void os::signal_init() {
319 if (!ReduceSignalUsage) {
320 // Setup JavaThread for processing signals
321 EXCEPTION_MARK;
322 Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(), true, CHECK);
323 instanceKlassHandle klass (THREAD, k);
324 instanceHandle thread_oop = klass->allocate_instance_handle(CHECK);
326 const char thread_name[] = "Signal Dispatcher";
327 Handle string = java_lang_String::create_from_str(thread_name, CHECK);
329 // Initialize thread_oop to put it into the system threadGroup
330 Handle thread_group (THREAD, Universe::system_thread_group());
331 JavaValue result(T_VOID);
332 JavaCalls::call_special(&result, thread_oop,
333 klass,
334 vmSymbols::object_initializer_name(),
335 vmSymbols::threadgroup_string_void_signature(),
336 thread_group,
337 string,
338 CHECK);
340 KlassHandle group(THREAD, SystemDictionary::ThreadGroup_klass());
341 JavaCalls::call_special(&result,
342 thread_group,
343 group,
344 vmSymbols::add_method_name(),
345 vmSymbols::thread_void_signature(),
346 thread_oop, // ARG 1
347 CHECK);
349 os::signal_init_pd();
351 { MutexLocker mu(Threads_lock);
352 JavaThread* signal_thread = new JavaThread(&signal_thread_entry);
354 // At this point it may be possible that no osthread was created for the
355 // JavaThread due to lack of memory. We would have to throw an exception
356 // in that case. However, since this must work and we do not allow
357 // exceptions anyway, check and abort if this fails.
358 if (signal_thread == NULL || signal_thread->osthread() == NULL) {
359 vm_exit_during_initialization("java.lang.OutOfMemoryError",
360 "unable to create new native thread");
361 }
363 java_lang_Thread::set_thread(thread_oop(), signal_thread);
364 java_lang_Thread::set_priority(thread_oop(), NearMaxPriority);
365 java_lang_Thread::set_daemon(thread_oop());
367 signal_thread->set_threadObj(thread_oop());
368 Threads::add(signal_thread);
369 Thread::start(signal_thread);
370 }
371 // Handle ^BREAK
372 os::signal(SIGBREAK, os::user_handler());
373 }
374 }
377 void os::terminate_signal_thread() {
378 if (!ReduceSignalUsage)
379 signal_notify(sigexitnum_pd());
380 }
383 // --------------------- loading libraries ---------------------
385 typedef jint (JNICALL *JNI_OnLoad_t)(JavaVM *, void *);
386 extern struct JavaVM_ main_vm;
388 static void* _native_java_library = NULL;
390 void* os::native_java_library() {
391 if (_native_java_library == NULL) {
392 char buffer[JVM_MAXPATHLEN];
393 char ebuf[1024];
395 // Try to load verify dll first. In 1.3 java dll depends on it and is not
396 // always able to find it when the loading executable is outside the JDK.
397 // In order to keep working with 1.2 we ignore any loading errors.
398 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
399 "verify")) {
400 dll_load(buffer, ebuf, sizeof(ebuf));
401 }
403 // Load java dll
404 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
405 "java")) {
406 _native_java_library = dll_load(buffer, ebuf, sizeof(ebuf));
407 }
408 if (_native_java_library == NULL) {
409 vm_exit_during_initialization("Unable to load native library", ebuf);
410 }
412 #if defined(__OpenBSD__)
413 // Work-around OpenBSD's lack of $ORIGIN support by pre-loading libnet.so
414 // ignore errors
415 if (dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(),
416 "net")) {
417 dll_load(buffer, ebuf, sizeof(ebuf));
418 }
419 #endif
420 }
421 static jboolean onLoaded = JNI_FALSE;
422 if (onLoaded) {
423 // We may have to wait to fire OnLoad until TLS is initialized.
424 if (ThreadLocalStorage::is_initialized()) {
425 // The JNI_OnLoad handling is normally done by method load in
426 // java.lang.ClassLoader$NativeLibrary, but the VM loads the base library
427 // explicitly so we have to check for JNI_OnLoad as well
428 const char *onLoadSymbols[] = JNI_ONLOAD_SYMBOLS;
429 JNI_OnLoad_t JNI_OnLoad = CAST_TO_FN_PTR(
430 JNI_OnLoad_t, dll_lookup(_native_java_library, onLoadSymbols[0]));
431 if (JNI_OnLoad != NULL) {
432 JavaThread* thread = JavaThread::current();
433 ThreadToNativeFromVM ttn(thread);
434 HandleMark hm(thread);
435 jint ver = (*JNI_OnLoad)(&main_vm, NULL);
436 onLoaded = JNI_TRUE;
437 if (!Threads::is_supported_jni_version_including_1_1(ver)) {
438 vm_exit_during_initialization("Unsupported JNI version");
439 }
440 }
441 }
442 }
443 return _native_java_library;
444 }
446 /*
447 * Support for finding Agent_On(Un)Load/Attach<_lib_name> if it exists.
448 * If check_lib == true then we are looking for an
449 * Agent_OnLoad_lib_name or Agent_OnAttach_lib_name function to determine if
450 * this library is statically linked into the image.
451 * If check_lib == false then we will look for the appropriate symbol in the
452 * executable if agent_lib->is_static_lib() == true or in the shared library
453 * referenced by 'handle'.
454 */
455 void* os::find_agent_function(AgentLibrary *agent_lib, bool check_lib,
456 const char *syms[], size_t syms_len) {
457 assert(agent_lib != NULL, "sanity check");
458 const char *lib_name;
459 void *handle = agent_lib->os_lib();
460 void *entryName = NULL;
461 char *agent_function_name;
462 size_t i;
464 // If checking then use the agent name otherwise test is_static_lib() to
465 // see how to process this lookup
466 lib_name = ((check_lib || agent_lib->is_static_lib()) ? agent_lib->name() : NULL);
467 for (i = 0; i < syms_len; i++) {
468 agent_function_name = build_agent_function_name(syms[i], lib_name, agent_lib->is_absolute_path());
469 if (agent_function_name == NULL) {
470 break;
471 }
472 entryName = dll_lookup(handle, agent_function_name);
473 FREE_C_HEAP_ARRAY(char, agent_function_name, mtThread);
474 if (entryName != NULL) {
475 break;
476 }
477 }
478 return entryName;
479 }
481 // See if the passed in agent is statically linked into the VM image.
482 bool os::find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
483 size_t syms_len) {
484 void *ret;
485 void *proc_handle;
486 void *save_handle;
488 assert(agent_lib != NULL, "sanity check");
489 if (agent_lib->name() == NULL) {
490 return false;
491 }
492 proc_handle = get_default_process_handle();
493 // Check for Agent_OnLoad/Attach_lib_name function
494 save_handle = agent_lib->os_lib();
495 // We want to look in this process' symbol table.
496 agent_lib->set_os_lib(proc_handle);
497 ret = find_agent_function(agent_lib, true, syms, syms_len);
498 if (ret != NULL) {
499 // Found an entry point like Agent_OnLoad_lib_name so we have a static agent
500 agent_lib->set_valid();
501 agent_lib->set_static_lib(true);
502 return true;
503 }
504 agent_lib->set_os_lib(save_handle);
505 return false;
506 }
508 // --------------------- heap allocation utilities ---------------------
510 char *os::strdup(const char *str, MEMFLAGS flags) {
511 size_t size = strlen(str);
512 char *dup_str = (char *)malloc(size + 1, flags);
513 if (dup_str == NULL) return NULL;
514 strcpy(dup_str, str);
515 return dup_str;
516 }
520 #ifdef ASSERT
521 #define space_before (MallocCushion + sizeof(double))
522 #define space_after MallocCushion
523 #define size_addr_from_base(p) (size_t*)(p + space_before - sizeof(size_t))
524 #define size_addr_from_obj(p) ((size_t*)p - 1)
525 // MallocCushion: size of extra cushion allocated around objects with +UseMallocOnly
526 // NB: cannot be debug variable, because these aren't set from the command line until
527 // *after* the first few allocs already happened
528 #define MallocCushion 16
529 #else
530 #define space_before 0
531 #define space_after 0
532 #define size_addr_from_base(p) should not use w/o ASSERT
533 #define size_addr_from_obj(p) should not use w/o ASSERT
534 #define MallocCushion 0
535 #endif
536 #define paranoid 0 /* only set to 1 if you suspect checking code has bug */
538 #ifdef ASSERT
539 inline size_t get_size(void* obj) {
540 size_t size = *size_addr_from_obj(obj);
541 if (size < 0) {
542 fatal(err_msg("free: size field of object #" PTR_FORMAT " was overwritten ("
543 SIZE_FORMAT ")", obj, size));
544 }
545 return size;
546 }
548 u_char* find_cushion_backwards(u_char* start) {
549 u_char* p = start;
550 while (p[ 0] != badResourceValue || p[-1] != badResourceValue ||
551 p[-2] != badResourceValue || p[-3] != badResourceValue) p--;
552 // ok, we have four consecutive marker bytes; find start
553 u_char* q = p - 4;
554 while (*q == badResourceValue) q--;
555 return q + 1;
556 }
558 u_char* find_cushion_forwards(u_char* start) {
559 u_char* p = start;
560 while (p[0] != badResourceValue || p[1] != badResourceValue ||
561 p[2] != badResourceValue || p[3] != badResourceValue) p++;
562 // ok, we have four consecutive marker bytes; find end of cushion
563 u_char* q = p + 4;
564 while (*q == badResourceValue) q++;
565 return q - MallocCushion;
566 }
568 void print_neighbor_blocks(void* ptr) {
569 // find block allocated before ptr (not entirely crash-proof)
570 if (MallocCushion < 4) {
571 tty->print_cr("### cannot find previous block (MallocCushion < 4)");
572 return;
573 }
574 u_char* start_of_this_block = (u_char*)ptr - space_before;
575 u_char* end_of_prev_block_data = start_of_this_block - space_after -1;
576 // look for cushion in front of prev. block
577 u_char* start_of_prev_block = find_cushion_backwards(end_of_prev_block_data);
578 ptrdiff_t size = *size_addr_from_base(start_of_prev_block);
579 u_char* obj = start_of_prev_block + space_before;
580 if (size <= 0 ) {
581 // start is bad; mayhave been confused by OS data inbetween objects
582 // search one more backwards
583 start_of_prev_block = find_cushion_backwards(start_of_prev_block);
584 size = *size_addr_from_base(start_of_prev_block);
585 obj = start_of_prev_block + space_before;
586 }
588 if (start_of_prev_block + space_before + size + space_after == start_of_this_block) {
589 tty->print_cr("### previous object: " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", obj, size);
590 } else {
591 tty->print_cr("### previous object (not sure if correct): " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", obj, size);
592 }
594 // now find successor block
595 u_char* start_of_next_block = (u_char*)ptr + *size_addr_from_obj(ptr) + space_after;
596 start_of_next_block = find_cushion_forwards(start_of_next_block);
597 u_char* next_obj = start_of_next_block + space_before;
598 ptrdiff_t next_size = *size_addr_from_base(start_of_next_block);
599 if (start_of_next_block[0] == badResourceValue &&
600 start_of_next_block[1] == badResourceValue &&
601 start_of_next_block[2] == badResourceValue &&
602 start_of_next_block[3] == badResourceValue) {
603 tty->print_cr("### next object: " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", next_obj, next_size);
604 } else {
605 tty->print_cr("### next object (not sure if correct): " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", next_obj, next_size);
606 }
607 }
610 void report_heap_error(void* memblock, void* bad, const char* where) {
611 tty->print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees);
612 tty->print_cr("## memory stomp: byte at " PTR_FORMAT " %s object " PTR_FORMAT, bad, where, memblock);
613 print_neighbor_blocks(memblock);
614 fatal("memory stomping error");
615 }
617 void verify_block(void* memblock) {
618 size_t size = get_size(memblock);
619 if (MallocCushion) {
620 u_char* ptr = (u_char*)memblock - space_before;
621 for (int i = 0; i < MallocCushion; i++) {
622 if (ptr[i] != badResourceValue) {
623 report_heap_error(memblock, ptr+i, "in front of");
624 }
625 }
626 u_char* end = (u_char*)memblock + size + space_after;
627 for (int j = -MallocCushion; j < 0; j++) {
628 if (end[j] != badResourceValue) {
629 report_heap_error(memblock, end+j, "after");
630 }
631 }
632 }
633 }
634 #endif
636 //
637 // This function supports testing of the malloc out of memory
638 // condition without really running the system out of memory.
639 //
640 static u_char* testMalloc(size_t alloc_size) {
641 assert(MallocMaxTestWords > 0, "sanity check");
643 if ((cur_malloc_words + (alloc_size / BytesPerWord)) > MallocMaxTestWords) {
644 return NULL;
645 }
647 u_char* ptr = (u_char*)::malloc(alloc_size);
649 if (ptr != NULL) {
650 Atomic::add(((jint) (alloc_size / BytesPerWord)),
651 (volatile jint *) &cur_malloc_words);
652 }
653 return ptr;
654 }
656 void* os::malloc(size_t size, MEMFLAGS memflags, address caller) {
657 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
658 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
660 #ifdef ASSERT
661 // checking for the WatcherThread and crash_protection first
662 // since os::malloc can be called when the libjvm.{dll,so} is
663 // first loaded and we don't have a thread yet.
664 // try to find the thread after we see that the watcher thread
665 // exists and has crash protection.
666 WatcherThread *wt = WatcherThread::watcher_thread();
667 if (wt != NULL && wt->has_crash_protection()) {
668 Thread* thread = ThreadLocalStorage::get_thread_slow();
669 if (thread == wt) {
670 assert(!wt->has_crash_protection(),
671 "Can't malloc with crash protection from WatcherThread");
672 }
673 }
674 #endif
676 if (size == 0) {
677 // return a valid pointer if size is zero
678 // if NULL is returned the calling functions assume out of memory.
679 size = 1;
680 }
682 const size_t alloc_size = size + space_before + space_after;
684 if (size > alloc_size) { // Check for rollover.
685 return NULL;
686 }
688 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
690 u_char* ptr;
692 if (MallocMaxTestWords > 0) {
693 ptr = testMalloc(alloc_size);
694 } else {
695 ptr = (u_char*)::malloc(alloc_size);
696 }
698 #ifdef ASSERT
699 if (ptr == NULL) return NULL;
700 if (MallocCushion) {
701 for (u_char* p = ptr; p < ptr + MallocCushion; p++) *p = (u_char)badResourceValue;
702 u_char* end = ptr + space_before + size;
703 for (u_char* pq = ptr+MallocCushion; pq < end; pq++) *pq = (u_char)uninitBlockPad;
704 for (u_char* q = end; q < end + MallocCushion; q++) *q = (u_char)badResourceValue;
705 }
706 // put size just before data
707 *size_addr_from_base(ptr) = size;
708 #endif
709 u_char* memblock = ptr + space_before;
710 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
711 tty->print_cr("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, memblock);
712 breakpoint();
713 }
714 debug_only(if (paranoid) verify_block(memblock));
715 if (PrintMalloc && tty != NULL) tty->print_cr("os::malloc " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, memblock);
717 // we do not track MallocCushion memory
718 MemTracker::record_malloc((address)memblock, size, memflags, caller == 0 ? CALLER_PC : caller);
720 return memblock;
721 }
724 void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, address caller) {
725 #ifndef ASSERT
726 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
727 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
728 MemTracker::Tracker tkr = MemTracker::get_realloc_tracker();
729 void* ptr = ::realloc(memblock, size);
730 if (ptr != NULL) {
731 tkr.record((address)memblock, (address)ptr, size, memflags,
732 caller == 0 ? CALLER_PC : caller);
733 } else {
734 tkr.discard();
735 }
736 return ptr;
737 #else
738 if (memblock == NULL) {
739 return malloc(size, memflags, (caller == 0 ? CALLER_PC : caller));
740 }
741 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
742 tty->print_cr("os::realloc caught " PTR_FORMAT, memblock);
743 breakpoint();
744 }
745 verify_block(memblock);
746 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
747 if (size == 0) return NULL;
748 // always move the block
749 void* ptr = malloc(size, memflags, caller == 0 ? CALLER_PC : caller);
750 if (PrintMalloc) tty->print_cr("os::remalloc " SIZE_FORMAT " bytes, " PTR_FORMAT " --> " PTR_FORMAT, size, memblock, ptr);
751 // Copy to new memory if malloc didn't fail
752 if ( ptr != NULL ) {
753 memcpy(ptr, memblock, MIN2(size, get_size(memblock)));
754 if (paranoid) verify_block(ptr);
755 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) {
756 tty->print_cr("os::realloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr);
757 breakpoint();
758 }
759 free(memblock);
760 }
761 return ptr;
762 #endif
763 }
766 void os::free(void *memblock, MEMFLAGS memflags) {
767 NOT_PRODUCT(inc_stat_counter(&num_frees, 1));
768 #ifdef ASSERT
769 if (memblock == NULL) return;
770 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
771 if (tty != NULL) tty->print_cr("os::free caught " PTR_FORMAT, memblock);
772 breakpoint();
773 }
774 verify_block(memblock);
775 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
776 // Added by detlefs.
777 if (MallocCushion) {
778 u_char* ptr = (u_char*)memblock - space_before;
779 for (u_char* p = ptr; p < ptr + MallocCushion; p++) {
780 guarantee(*p == badResourceValue,
781 "Thing freed should be malloc result.");
782 *p = (u_char)freeBlockPad;
783 }
784 size_t size = get_size(memblock);
785 inc_stat_counter(&free_bytes, size);
786 u_char* end = ptr + space_before + size;
787 for (u_char* q = end; q < end + MallocCushion; q++) {
788 guarantee(*q == badResourceValue,
789 "Thing freed should be malloc result.");
790 *q = (u_char)freeBlockPad;
791 }
792 if (PrintMalloc && tty != NULL)
793 fprintf(stderr, "os::free " SIZE_FORMAT " bytes --> " PTR_FORMAT "\n", size, (uintptr_t)memblock);
794 } else if (PrintMalloc && tty != NULL) {
795 // tty->print_cr("os::free %p", memblock);
796 fprintf(stderr, "os::free " PTR_FORMAT "\n", (uintptr_t)memblock);
797 }
798 #endif
799 MemTracker::record_free((address)memblock, memflags);
801 ::free((char*)memblock - space_before);
802 }
804 void os::init_random(long initval) {
805 _rand_seed = initval;
806 }
809 long os::random() {
810 /* standard, well-known linear congruential random generator with
811 * next_rand = (16807*seed) mod (2**31-1)
812 * see
813 * (1) "Random Number Generators: Good Ones Are Hard to Find",
814 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988),
815 * (2) "Two Fast Implementations of the 'Minimal Standard' Random
816 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88.
817 */
818 const long a = 16807;
819 const unsigned long m = 2147483647;
820 const long q = m / a; assert(q == 127773, "weird math");
821 const long r = m % a; assert(r == 2836, "weird math");
823 // compute az=2^31p+q
824 unsigned long lo = a * (long)(_rand_seed & 0xFFFF);
825 unsigned long hi = a * (long)((unsigned long)_rand_seed >> 16);
826 lo += (hi & 0x7FFF) << 16;
828 // if q overflowed, ignore the overflow and increment q
829 if (lo > m) {
830 lo &= m;
831 ++lo;
832 }
833 lo += hi >> 15;
835 // if (p+q) overflowed, ignore the overflow and increment (p+q)
836 if (lo > m) {
837 lo &= m;
838 ++lo;
839 }
840 return (_rand_seed = lo);
841 }
843 // The INITIALIZED state is distinguished from the SUSPENDED state because the
844 // conditions in which a thread is first started are different from those in which
845 // a suspension is resumed. These differences make it hard for us to apply the
846 // tougher checks when starting threads that we want to do when resuming them.
847 // However, when start_thread is called as a result of Thread.start, on a Java
848 // thread, the operation is synchronized on the Java Thread object. So there
849 // cannot be a race to start the thread and hence for the thread to exit while
850 // we are working on it. Non-Java threads that start Java threads either have
851 // to do so in a context in which races are impossible, or should do appropriate
852 // locking.
854 void os::start_thread(Thread* thread) {
855 // guard suspend/resume
856 MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag);
857 OSThread* osthread = thread->osthread();
858 osthread->set_state(RUNNABLE);
859 pd_start_thread(thread);
860 }
862 //---------------------------------------------------------------------------
863 // Helper functions for fatal error handler
865 void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) {
866 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking");
868 int cols = 0;
869 int cols_per_line = 0;
870 switch (unitsize) {
871 case 1: cols_per_line = 16; break;
872 case 2: cols_per_line = 8; break;
873 case 4: cols_per_line = 4; break;
874 case 8: cols_per_line = 2; break;
875 default: return;
876 }
878 address p = start;
879 st->print(PTR_FORMAT ": ", start);
880 while (p < end) {
881 switch (unitsize) {
882 case 1: st->print("%02x", *(u1*)p); break;
883 case 2: st->print("%04x", *(u2*)p); break;
884 case 4: st->print("%08x", *(u4*)p); break;
885 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break;
886 }
887 p += unitsize;
888 cols++;
889 if (cols >= cols_per_line && p < end) {
890 cols = 0;
891 st->cr();
892 st->print(PTR_FORMAT ": ", p);
893 } else {
894 st->print(" ");
895 }
896 }
897 st->cr();
898 }
900 void os::print_environment_variables(outputStream* st, const char** env_list,
901 char* buffer, int len) {
902 if (env_list) {
903 st->print_cr("Environment Variables:");
905 for (int i = 0; env_list[i] != NULL; i++) {
906 if (getenv(env_list[i], buffer, len)) {
907 st->print(env_list[i]);
908 st->print("=");
909 st->print_cr(buffer);
910 }
911 }
912 }
913 }
915 void os::print_cpu_info(outputStream* st) {
916 // cpu
917 st->print("CPU:");
918 st->print("total %d", os::processor_count());
919 // It's not safe to query number of active processors after crash
920 // st->print("(active %d)", os::active_processor_count());
921 st->print(" %s", VM_Version::cpu_features());
922 st->cr();
923 pd_print_cpu_info(st);
924 }
926 void os::print_date_and_time(outputStream *st) {
927 time_t tloc;
928 (void)time(&tloc);
929 st->print("time: %s", ctime(&tloc)); // ctime adds newline.
931 double t = os::elapsedTime();
932 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in
933 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int
934 // before printf. We lost some precision, but who cares?
935 st->print_cr("elapsed time: %d seconds", (int)t);
936 }
938 // moved from debug.cpp (used to be find()) but still called from there
939 // The verbose parameter is only set by the debug code in one case
940 void os::print_location(outputStream* st, intptr_t x, bool verbose) {
941 address addr = (address)x;
942 CodeBlob* b = CodeCache::find_blob_unsafe(addr);
943 if (b != NULL) {
944 if (b->is_buffer_blob()) {
945 // the interpreter is generated into a buffer blob
946 InterpreterCodelet* i = Interpreter::codelet_containing(addr);
947 if (i != NULL) {
948 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an Interpreter codelet", addr, (int)(addr - i->code_begin()));
949 i->print_on(st);
950 return;
951 }
952 if (Interpreter::contains(addr)) {
953 st->print_cr(INTPTR_FORMAT " is pointing into interpreter code"
954 " (not bytecode specific)", addr);
955 return;
956 }
957 //
958 if (AdapterHandlerLibrary::contains(b)) {
959 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an AdapterHandler", addr, (int)(addr - b->code_begin()));
960 AdapterHandlerLibrary::print_handler_on(st, b);
961 }
962 // the stubroutines are generated into a buffer blob
963 StubCodeDesc* d = StubCodeDesc::desc_for(addr);
964 if (d != NULL) {
965 st->print_cr(INTPTR_FORMAT " is at begin+%d in a stub", addr, (int)(addr - d->begin()));
966 d->print_on(st);
967 st->cr();
968 return;
969 }
970 if (StubRoutines::contains(addr)) {
971 st->print_cr(INTPTR_FORMAT " is pointing to an (unnamed) "
972 "stub routine", addr);
973 return;
974 }
975 // the InlineCacheBuffer is using stubs generated into a buffer blob
976 if (InlineCacheBuffer::contains(addr)) {
977 st->print_cr(INTPTR_FORMAT " is pointing into InlineCacheBuffer", addr);
978 return;
979 }
980 VtableStub* v = VtableStubs::stub_containing(addr);
981 if (v != NULL) {
982 st->print_cr(INTPTR_FORMAT " is at entry_point+%d in a vtable stub", addr, (int)(addr - v->entry_point()));
983 v->print_on(st);
984 st->cr();
985 return;
986 }
987 }
988 nmethod* nm = b->as_nmethod_or_null();
989 if (nm != NULL) {
990 ResourceMark rm;
991 st->print(INTPTR_FORMAT " is at entry_point+%d in (nmethod*)" INTPTR_FORMAT,
992 addr, (int)(addr - nm->entry_point()), nm);
993 if (verbose) {
994 st->print(" for ");
995 nm->method()->print_value_on(st);
996 }
997 st->cr();
998 nm->print_nmethod(verbose);
999 return;
1000 }
1001 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in ", addr, (int)(addr - b->code_begin()));
1002 b->print_on(st);
1003 return;
1004 }
1006 if (Universe::heap()->is_in(addr)) {
1007 HeapWord* p = Universe::heap()->block_start(addr);
1008 bool print = false;
1009 // If we couldn't find it it just may mean that heap wasn't parseable
1010 // See if we were just given an oop directly
1011 if (p != NULL && Universe::heap()->block_is_obj(p)) {
1012 print = true;
1013 } else if (p == NULL && ((oopDesc*)addr)->is_oop()) {
1014 p = (HeapWord*) addr;
1015 print = true;
1016 }
1017 if (print) {
1018 if (p == (HeapWord*) addr) {
1019 st->print_cr(INTPTR_FORMAT " is an oop", addr);
1020 } else {
1021 st->print_cr(INTPTR_FORMAT " is pointing into object: " INTPTR_FORMAT, addr, p);
1022 }
1023 oop(p)->print_on(st);
1024 return;
1025 }
1026 } else {
1027 if (Universe::heap()->is_in_reserved(addr)) {
1028 st->print_cr(INTPTR_FORMAT " is an unallocated location "
1029 "in the heap", addr);
1030 return;
1031 }
1032 }
1033 if (JNIHandles::is_global_handle((jobject) addr)) {
1034 st->print_cr(INTPTR_FORMAT " is a global jni handle", addr);
1035 return;
1036 }
1037 if (JNIHandles::is_weak_global_handle((jobject) addr)) {
1038 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", addr);
1039 return;
1040 }
1041 #ifndef PRODUCT
1042 // we don't keep the block list in product mode
1043 if (JNIHandleBlock::any_contains((jobject) addr)) {
1044 st->print_cr(INTPTR_FORMAT " is a local jni handle", addr);
1045 return;
1046 }
1047 #endif
1049 for(JavaThread *thread = Threads::first(); thread; thread = thread->next()) {
1050 // Check for privilege stack
1051 if (thread->privileged_stack_top() != NULL &&
1052 thread->privileged_stack_top()->contains(addr)) {
1053 st->print_cr(INTPTR_FORMAT " is pointing into the privilege stack "
1054 "for thread: " INTPTR_FORMAT, addr, thread);
1055 if (verbose) thread->print_on(st);
1056 return;
1057 }
1058 // If the addr is a java thread print information about that.
1059 if (addr == (address)thread) {
1060 if (verbose) {
1061 thread->print_on(st);
1062 } else {
1063 st->print_cr(INTPTR_FORMAT " is a thread", addr);
1064 }
1065 return;
1066 }
1067 // If the addr is in the stack region for this thread then report that
1068 // and print thread info
1069 if (thread->stack_base() >= addr &&
1070 addr > (thread->stack_base() - thread->stack_size())) {
1071 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: "
1072 INTPTR_FORMAT, addr, thread);
1073 if (verbose) thread->print_on(st);
1074 return;
1075 }
1077 }
1079 #ifndef PRODUCT
1080 // Check if in metaspace.
1081 if (ClassLoaderDataGraph::contains((address)addr)) {
1082 // Use addr->print() from the debugger instead (not here)
1083 st->print_cr(INTPTR_FORMAT
1084 " is pointing into metadata", addr);
1085 return;
1086 }
1087 #endif
1089 // Try an OS specific find
1090 if (os::find(addr, st)) {
1091 return;
1092 }
1094 st->print_cr(INTPTR_FORMAT " is an unknown value", addr);
1095 }
1097 // Looks like all platforms except IA64 can use the same function to check
1098 // if C stack is walkable beyond current frame. The check for fp() is not
1099 // necessary on Sparc, but it's harmless.
1100 bool os::is_first_C_frame(frame* fr) {
1101 #if defined(IA64) && !defined(_WIN32)
1102 // On IA64 we have to check if the callers bsp is still valid
1103 // (i.e. within the register stack bounds).
1104 // Notice: this only works for threads created by the VM and only if
1105 // we walk the current stack!!! If we want to be able to walk
1106 // arbitrary other threads, we'll have to somehow store the thread
1107 // object in the frame.
1108 Thread *thread = Thread::current();
1109 if ((address)fr->fp() <=
1110 thread->register_stack_base() HPUX_ONLY(+ 0x0) LINUX_ONLY(+ 0x50)) {
1111 // This check is a little hacky, because on Linux the first C
1112 // frame's ('start_thread') register stack frame starts at
1113 // "register_stack_base + 0x48" while on HPUX, the first C frame's
1114 // ('__pthread_bound_body') register stack frame seems to really
1115 // start at "register_stack_base".
1116 return true;
1117 } else {
1118 return false;
1119 }
1120 #elif defined(IA64) && defined(_WIN32)
1121 return true;
1122 #else
1123 // Load up sp, fp, sender sp and sender fp, check for reasonable values.
1124 // Check usp first, because if that's bad the other accessors may fault
1125 // on some architectures. Ditto ufp second, etc.
1126 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1);
1127 // sp on amd can be 32 bit aligned.
1128 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1);
1130 uintptr_t usp = (uintptr_t)fr->sp();
1131 if ((usp & sp_align_mask) != 0) return true;
1133 uintptr_t ufp = (uintptr_t)fr->fp();
1134 if ((ufp & fp_align_mask) != 0) return true;
1136 uintptr_t old_sp = (uintptr_t)fr->sender_sp();
1137 if ((old_sp & sp_align_mask) != 0) return true;
1138 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true;
1140 uintptr_t old_fp = (uintptr_t)fr->link();
1141 if ((old_fp & fp_align_mask) != 0) return true;
1142 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true;
1144 // stack grows downwards; if old_fp is below current fp or if the stack
1145 // frame is too large, either the stack is corrupted or fp is not saved
1146 // on stack (i.e. on x86, ebp may be used as general register). The stack
1147 // is not walkable beyond current frame.
1148 if (old_fp < ufp) return true;
1149 if (old_fp - ufp > 64 * K) return true;
1151 return false;
1152 #endif
1153 }
1155 #ifdef ASSERT
1156 extern "C" void test_random() {
1157 const double m = 2147483647;
1158 double mean = 0.0, variance = 0.0, t;
1159 long reps = 10000;
1160 unsigned long seed = 1;
1162 tty->print_cr("seed %ld for %ld repeats...", seed, reps);
1163 os::init_random(seed);
1164 long num;
1165 for (int k = 0; k < reps; k++) {
1166 num = os::random();
1167 double u = (double)num / m;
1168 assert(u >= 0.0 && u <= 1.0, "bad random number!");
1170 // calculate mean and variance of the random sequence
1171 mean += u;
1172 variance += (u*u);
1173 }
1174 mean /= reps;
1175 variance /= (reps - 1);
1177 assert(num == 1043618065, "bad seed");
1178 tty->print_cr("mean of the 1st 10000 numbers: %f", mean);
1179 tty->print_cr("variance of the 1st 10000 numbers: %f", variance);
1180 const double eps = 0.0001;
1181 t = fabsd(mean - 0.5018);
1182 assert(t < eps, "bad mean");
1183 t = (variance - 0.3355) < 0.0 ? -(variance - 0.3355) : variance - 0.3355;
1184 assert(t < eps, "bad variance");
1185 }
1186 #endif
1189 // Set up the boot classpath.
1191 char* os::format_boot_path(const char* format_string,
1192 const char* home,
1193 int home_len,
1194 char fileSep,
1195 char pathSep) {
1196 assert((fileSep == '/' && pathSep == ':') ||
1197 (fileSep == '\\' && pathSep == ';'), "unexpected seperator chars");
1199 // Scan the format string to determine the length of the actual
1200 // boot classpath, and handle platform dependencies as well.
1201 int formatted_path_len = 0;
1202 const char* p;
1203 for (p = format_string; *p != 0; ++p) {
1204 if (*p == '%') formatted_path_len += home_len - 1;
1205 ++formatted_path_len;
1206 }
1208 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal);
1209 if (formatted_path == NULL) {
1210 return NULL;
1211 }
1213 // Create boot classpath from format, substituting separator chars and
1214 // java home directory.
1215 char* q = formatted_path;
1216 for (p = format_string; *p != 0; ++p) {
1217 switch (*p) {
1218 case '%':
1219 strcpy(q, home);
1220 q += home_len;
1221 break;
1222 case '/':
1223 *q++ = fileSep;
1224 break;
1225 case ':':
1226 *q++ = pathSep;
1227 break;
1228 default:
1229 *q++ = *p;
1230 }
1231 }
1232 *q = '\0';
1234 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched");
1235 return formatted_path;
1236 }
1239 bool os::set_boot_path(char fileSep, char pathSep) {
1240 const char* home = Arguments::get_java_home();
1241 int home_len = (int)strlen(home);
1243 static const char* meta_index_dir_format = "%/lib/";
1244 static const char* meta_index_format = "%/lib/meta-index";
1245 char* meta_index = format_boot_path(meta_index_format, home, home_len, fileSep, pathSep);
1246 if (meta_index == NULL) return false;
1247 char* meta_index_dir = format_boot_path(meta_index_dir_format, home, home_len, fileSep, pathSep);
1248 if (meta_index_dir == NULL) return false;
1249 Arguments::set_meta_index_path(meta_index, meta_index_dir);
1251 // Any modification to the JAR-file list, for the boot classpath must be
1252 // aligned with install/install/make/common/Pack.gmk. Note: boot class
1253 // path class JARs, are stripped for StackMapTable to reduce download size.
1254 static const char classpath_format[] =
1255 "%/lib/resources.jar:"
1256 "%/lib/rt.jar:"
1257 "%/lib/sunrsasign.jar:"
1258 "%/lib/jsse.jar:"
1259 "%/lib/jce.jar:"
1260 "%/lib/charsets.jar:"
1261 "%/lib/jfr.jar:"
1262 #ifdef __APPLE__
1263 "%/lib/JObjC.jar:"
1264 #endif
1265 "%/classes";
1266 char* sysclasspath = format_boot_path(classpath_format, home, home_len, fileSep, pathSep);
1267 if (sysclasspath == NULL) return false;
1268 Arguments::set_sysclasspath(sysclasspath);
1270 return true;
1271 }
1273 /*
1274 * Splits a path, based on its separator, the number of
1275 * elements is returned back in n.
1276 * It is the callers responsibility to:
1277 * a> check the value of n, and n may be 0.
1278 * b> ignore any empty path elements
1279 * c> free up the data.
1280 */
1281 char** os::split_path(const char* path, int* n) {
1282 *n = 0;
1283 if (path == NULL || strlen(path) == 0) {
1284 return NULL;
1285 }
1286 const char psepchar = *os::path_separator();
1287 char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal);
1288 if (inpath == NULL) {
1289 return NULL;
1290 }
1291 strcpy(inpath, path);
1292 int count = 1;
1293 char* p = strchr(inpath, psepchar);
1294 // Get a count of elements to allocate memory
1295 while (p != NULL) {
1296 count++;
1297 p++;
1298 p = strchr(p, psepchar);
1299 }
1300 char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count, mtInternal);
1301 if (opath == NULL) {
1302 return NULL;
1303 }
1305 // do the actual splitting
1306 p = inpath;
1307 for (int i = 0 ; i < count ; i++) {
1308 size_t len = strcspn(p, os::path_separator());
1309 if (len > JVM_MAXPATHLEN) {
1310 return NULL;
1311 }
1312 // allocate the string and add terminator storage
1313 char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
1314 if (s == NULL) {
1315 return NULL;
1316 }
1317 strncpy(s, p, len);
1318 s[len] = '\0';
1319 opath[i] = s;
1320 p += len + 1;
1321 }
1322 FREE_C_HEAP_ARRAY(char, inpath, mtInternal);
1323 *n = count;
1324 return opath;
1325 }
1327 void os::set_memory_serialize_page(address page) {
1328 int count = log2_intptr(sizeof(class JavaThread)) - log2_intptr(64);
1329 _mem_serialize_page = (volatile int32_t *)page;
1330 // We initialize the serialization page shift count here
1331 // We assume a cache line size of 64 bytes
1332 assert(SerializePageShiftCount == count,
1333 "thread size changed, fix SerializePageShiftCount constant");
1334 set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t)));
1335 }
1337 static volatile intptr_t SerializePageLock = 0;
1339 // This method is called from signal handler when SIGSEGV occurs while the current
1340 // thread tries to store to the "read-only" memory serialize page during state
1341 // transition.
1342 void os::block_on_serialize_page_trap() {
1343 if (TraceSafepoint) {
1344 tty->print_cr("Block until the serialize page permission restored");
1345 }
1346 // When VMThread is holding the SerializePageLock during modifying the
1347 // access permission of the memory serialize page, the following call
1348 // will block until the permission of that page is restored to rw.
1349 // Generally, it is unsafe to manipulate locks in signal handlers, but in
1350 // this case, it's OK as the signal is synchronous and we know precisely when
1351 // it can occur.
1352 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page");
1353 Thread::muxRelease(&SerializePageLock);
1354 }
1356 // Serialize all thread state variables
1357 void os::serialize_thread_states() {
1358 // On some platforms such as Solaris & Linux, the time duration of the page
1359 // permission restoration is observed to be much longer than expected due to
1360 // scheduler starvation problem etc. To avoid the long synchronization
1361 // time and expensive page trap spinning, 'SerializePageLock' is used to block
1362 // the mutator thread if such case is encountered. See bug 6546278 for details.
1363 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states");
1364 os::protect_memory((char *)os::get_memory_serialize_page(),
1365 os::vm_page_size(), MEM_PROT_READ);
1366 os::protect_memory((char *)os::get_memory_serialize_page(),
1367 os::vm_page_size(), MEM_PROT_RW);
1368 Thread::muxRelease(&SerializePageLock);
1369 }
1371 // Returns true if the current stack pointer is above the stack shadow
1372 // pages, false otherwise.
1374 bool os::stack_shadow_pages_available(Thread *thread, methodHandle method) {
1375 assert(StackRedPages > 0 && StackYellowPages > 0,"Sanity check");
1376 address sp = current_stack_pointer();
1377 // Check if we have StackShadowPages above the yellow zone. This parameter
1378 // is dependent on the depth of the maximum VM call stack possible from
1379 // the handler for stack overflow. 'instanceof' in the stack overflow
1380 // handler or a println uses at least 8k stack of VM and native code
1381 // respectively.
1382 const int framesize_in_bytes =
1383 Interpreter::size_top_interpreter_activation(method()) * wordSize;
1384 int reserved_area = ((StackShadowPages + StackRedPages + StackYellowPages)
1385 * vm_page_size()) + framesize_in_bytes;
1386 // The very lower end of the stack
1387 address stack_limit = thread->stack_base() - thread->stack_size();
1388 return (sp > (stack_limit + reserved_area));
1389 }
1391 size_t os::page_size_for_region(size_t region_min_size, size_t region_max_size,
1392 uint min_pages)
1393 {
1394 assert(min_pages > 0, "sanity");
1395 if (UseLargePages) {
1396 const size_t max_page_size = region_max_size / min_pages;
1398 for (unsigned int i = 0; _page_sizes[i] != 0; ++i) {
1399 const size_t sz = _page_sizes[i];
1400 const size_t mask = sz - 1;
1401 if ((region_min_size & mask) == 0 && (region_max_size & mask) == 0) {
1402 // The largest page size with no fragmentation.
1403 return sz;
1404 }
1406 if (sz <= max_page_size) {
1407 // The largest page size that satisfies the min_pages requirement.
1408 return sz;
1409 }
1410 }
1411 }
1413 return vm_page_size();
1414 }
1416 #ifndef PRODUCT
1417 void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count)
1418 {
1419 if (TracePageSizes) {
1420 tty->print("%s: ", str);
1421 for (int i = 0; i < count; ++i) {
1422 tty->print(" " SIZE_FORMAT, page_sizes[i]);
1423 }
1424 tty->cr();
1425 }
1426 }
1428 void os::trace_page_sizes(const char* str, const size_t region_min_size,
1429 const size_t region_max_size, const size_t page_size,
1430 const char* base, const size_t size)
1431 {
1432 if (TracePageSizes) {
1433 tty->print_cr("%s: min=" SIZE_FORMAT " max=" SIZE_FORMAT
1434 " pg_sz=" SIZE_FORMAT " base=" PTR_FORMAT
1435 " size=" SIZE_FORMAT,
1436 str, region_min_size, region_max_size,
1437 page_size, base, size);
1438 }
1439 }
1440 #endif // #ifndef PRODUCT
1442 // This is the working definition of a server class machine:
1443 // >= 2 physical CPU's and >=2GB of memory, with some fuzz
1444 // because the graphics memory (?) sometimes masks physical memory.
1445 // If you want to change the definition of a server class machine
1446 // on some OS or platform, e.g., >=4GB on Windohs platforms,
1447 // then you'll have to parameterize this method based on that state,
1448 // as was done for logical processors here, or replicate and
1449 // specialize this method for each platform. (Or fix os to have
1450 // some inheritance structure and use subclassing. Sigh.)
1451 // If you want some platform to always or never behave as a server
1452 // class machine, change the setting of AlwaysActAsServerClassMachine
1453 // and NeverActAsServerClassMachine in globals*.hpp.
1454 bool os::is_server_class_machine() {
1455 // First check for the early returns
1456 if (NeverActAsServerClassMachine) {
1457 return false;
1458 }
1459 if (AlwaysActAsServerClassMachine) {
1460 return true;
1461 }
1462 // Then actually look at the machine
1463 bool result = false;
1464 const unsigned int server_processors = 2;
1465 const julong server_memory = 2UL * G;
1466 // We seem not to get our full complement of memory.
1467 // We allow some part (1/8?) of the memory to be "missing",
1468 // based on the sizes of DIMMs, and maybe graphics cards.
1469 const julong missing_memory = 256UL * M;
1471 /* Is this a server class machine? */
1472 if ((os::active_processor_count() >= (int)server_processors) &&
1473 (os::physical_memory() >= (server_memory - missing_memory))) {
1474 const unsigned int logical_processors =
1475 VM_Version::logical_processors_per_package();
1476 if (logical_processors > 1) {
1477 const unsigned int physical_packages =
1478 os::active_processor_count() / logical_processors;
1479 if (physical_packages > server_processors) {
1480 result = true;
1481 }
1482 } else {
1483 result = true;
1484 }
1485 }
1486 return result;
1487 }
1489 void os::SuspendedThreadTask::run() {
1490 assert(Threads_lock->owned_by_self() || (_thread == VMThread::vm_thread()), "must have threads lock to call this");
1491 internal_do_task();
1492 _done = true;
1493 }
1495 bool os::create_stack_guard_pages(char* addr, size_t bytes) {
1496 return os::pd_create_stack_guard_pages(addr, bytes);
1497 }
1499 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint) {
1500 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1501 if (result != NULL) {
1502 MemTracker::record_virtual_memory_reserve((address)result, bytes, mtNone, CALLER_PC);
1503 }
1505 return result;
1506 }
1508 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint,
1509 MEMFLAGS flags) {
1510 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1511 if (result != NULL) {
1512 MemTracker::record_virtual_memory_reserve((address)result, bytes, mtNone, CALLER_PC);
1513 MemTracker::record_virtual_memory_type((address)result, flags);
1514 }
1516 return result;
1517 }
1519 char* os::attempt_reserve_memory_at(size_t bytes, char* addr) {
1520 char* result = pd_attempt_reserve_memory_at(bytes, addr);
1521 if (result != NULL) {
1522 MemTracker::record_virtual_memory_reserve((address)result, bytes, mtNone, CALLER_PC);
1523 }
1524 return result;
1525 }
1527 void os::split_reserved_memory(char *base, size_t size,
1528 size_t split, bool realloc) {
1529 pd_split_reserved_memory(base, size, split, realloc);
1530 }
1532 bool os::commit_memory(char* addr, size_t bytes, bool executable) {
1533 bool res = pd_commit_memory(addr, bytes, executable);
1534 if (res) {
1535 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1536 }
1537 return res;
1538 }
1540 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint,
1541 bool executable) {
1542 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable);
1543 if (res) {
1544 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1545 }
1546 return res;
1547 }
1549 void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable,
1550 const char* mesg) {
1551 pd_commit_memory_or_exit(addr, bytes, executable, mesg);
1552 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1553 }
1555 void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint,
1556 bool executable, const char* mesg) {
1557 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg);
1558 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1559 }
1561 bool os::uncommit_memory(char* addr, size_t bytes) {
1562 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_uncommit_tracker();
1563 bool res = pd_uncommit_memory(addr, bytes);
1564 if (res) {
1565 tkr.record((address)addr, bytes);
1566 } else {
1567 tkr.discard();
1568 }
1569 return res;
1570 }
1572 bool os::release_memory(char* addr, size_t bytes) {
1573 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
1574 bool res = pd_release_memory(addr, bytes);
1575 if (res) {
1576 tkr.record((address)addr, bytes);
1577 } else {
1578 tkr.discard();
1579 }
1580 return res;
1581 }
1584 char* os::map_memory(int fd, const char* file_name, size_t file_offset,
1585 char *addr, size_t bytes, bool read_only,
1586 bool allow_exec) {
1587 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec);
1588 if (result != NULL) {
1589 MemTracker::record_virtual_memory_reserve_and_commit((address)result, bytes, mtNone, CALLER_PC);
1590 }
1591 return result;
1592 }
1594 char* os::remap_memory(int fd, const char* file_name, size_t file_offset,
1595 char *addr, size_t bytes, bool read_only,
1596 bool allow_exec) {
1597 return pd_remap_memory(fd, file_name, file_offset, addr, bytes,
1598 read_only, allow_exec);
1599 }
1601 bool os::unmap_memory(char *addr, size_t bytes) {
1602 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
1603 bool result = pd_unmap_memory(addr, bytes);
1604 if (result) {
1605 tkr.record((address)addr, bytes);
1606 } else {
1607 tkr.discard();
1608 }
1609 return result;
1610 }
1612 void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) {
1613 pd_free_memory(addr, bytes, alignment_hint);
1614 }
1616 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
1617 pd_realign_memory(addr, bytes, alignment_hint);
1618 }
1620 #ifndef TARGET_OS_FAMILY_windows
1621 /* try to switch state from state "from" to state "to"
1622 * returns the state set after the method is complete
1623 */
1624 os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from,
1625 os::SuspendResume::State to)
1626 {
1627 os::SuspendResume::State result =
1628 (os::SuspendResume::State) Atomic::cmpxchg((jint) to, (jint *) &_state, (jint) from);
1629 if (result == from) {
1630 // success
1631 return to;
1632 }
1633 return result;
1634 }
1635 #endif