Thu, 13 Jun 2013 11:16:38 -0700
8013057: assert(_needs_gc || SafepointSynchronize::is_at_safepoint()) failed: only read at safepoint
Summary: Detect mmap() commit failures in Linux and Solaris os::commit_memory() impls and call vm_exit_out_of_memory(). Add os::commit_memory_or_exit(). Also tidy up some NMT accounting and some mmap() return value checking.
Reviewed-by: zgu, stefank, dholmes, dsamersoff
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 // --------------------- heap allocation utilities ---------------------
448 char *os::strdup(const char *str, MEMFLAGS flags) {
449 size_t size = strlen(str);
450 char *dup_str = (char *)malloc(size + 1, flags);
451 if (dup_str == NULL) return NULL;
452 strcpy(dup_str, str);
453 return dup_str;
454 }
458 #ifdef ASSERT
459 #define space_before (MallocCushion + sizeof(double))
460 #define space_after MallocCushion
461 #define size_addr_from_base(p) (size_t*)(p + space_before - sizeof(size_t))
462 #define size_addr_from_obj(p) ((size_t*)p - 1)
463 // MallocCushion: size of extra cushion allocated around objects with +UseMallocOnly
464 // NB: cannot be debug variable, because these aren't set from the command line until
465 // *after* the first few allocs already happened
466 #define MallocCushion 16
467 #else
468 #define space_before 0
469 #define space_after 0
470 #define size_addr_from_base(p) should not use w/o ASSERT
471 #define size_addr_from_obj(p) should not use w/o ASSERT
472 #define MallocCushion 0
473 #endif
474 #define paranoid 0 /* only set to 1 if you suspect checking code has bug */
476 #ifdef ASSERT
477 inline size_t get_size(void* obj) {
478 size_t size = *size_addr_from_obj(obj);
479 if (size < 0) {
480 fatal(err_msg("free: size field of object #" PTR_FORMAT " was overwritten ("
481 SIZE_FORMAT ")", obj, size));
482 }
483 return size;
484 }
486 u_char* find_cushion_backwards(u_char* start) {
487 u_char* p = start;
488 while (p[ 0] != badResourceValue || p[-1] != badResourceValue ||
489 p[-2] != badResourceValue || p[-3] != badResourceValue) p--;
490 // ok, we have four consecutive marker bytes; find start
491 u_char* q = p - 4;
492 while (*q == badResourceValue) q--;
493 return q + 1;
494 }
496 u_char* find_cushion_forwards(u_char* start) {
497 u_char* p = start;
498 while (p[0] != badResourceValue || p[1] != badResourceValue ||
499 p[2] != badResourceValue || p[3] != badResourceValue) p++;
500 // ok, we have four consecutive marker bytes; find end of cushion
501 u_char* q = p + 4;
502 while (*q == badResourceValue) q++;
503 return q - MallocCushion;
504 }
506 void print_neighbor_blocks(void* ptr) {
507 // find block allocated before ptr (not entirely crash-proof)
508 if (MallocCushion < 4) {
509 tty->print_cr("### cannot find previous block (MallocCushion < 4)");
510 return;
511 }
512 u_char* start_of_this_block = (u_char*)ptr - space_before;
513 u_char* end_of_prev_block_data = start_of_this_block - space_after -1;
514 // look for cushion in front of prev. block
515 u_char* start_of_prev_block = find_cushion_backwards(end_of_prev_block_data);
516 ptrdiff_t size = *size_addr_from_base(start_of_prev_block);
517 u_char* obj = start_of_prev_block + space_before;
518 if (size <= 0 ) {
519 // start is bad; mayhave been confused by OS data inbetween objects
520 // search one more backwards
521 start_of_prev_block = find_cushion_backwards(start_of_prev_block);
522 size = *size_addr_from_base(start_of_prev_block);
523 obj = start_of_prev_block + space_before;
524 }
526 if (start_of_prev_block + space_before + size + space_after == start_of_this_block) {
527 tty->print_cr("### previous object: " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", obj, size);
528 } else {
529 tty->print_cr("### previous object (not sure if correct): " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", obj, size);
530 }
532 // now find successor block
533 u_char* start_of_next_block = (u_char*)ptr + *size_addr_from_obj(ptr) + space_after;
534 start_of_next_block = find_cushion_forwards(start_of_next_block);
535 u_char* next_obj = start_of_next_block + space_before;
536 ptrdiff_t next_size = *size_addr_from_base(start_of_next_block);
537 if (start_of_next_block[0] == badResourceValue &&
538 start_of_next_block[1] == badResourceValue &&
539 start_of_next_block[2] == badResourceValue &&
540 start_of_next_block[3] == badResourceValue) {
541 tty->print_cr("### next object: " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", next_obj, next_size);
542 } else {
543 tty->print_cr("### next object (not sure if correct): " PTR_FORMAT " (" SSIZE_FORMAT " bytes)", next_obj, next_size);
544 }
545 }
548 void report_heap_error(void* memblock, void* bad, const char* where) {
549 tty->print_cr("## nof_mallocs = " UINT64_FORMAT ", nof_frees = " UINT64_FORMAT, os::num_mallocs, os::num_frees);
550 tty->print_cr("## memory stomp: byte at " PTR_FORMAT " %s object " PTR_FORMAT, bad, where, memblock);
551 print_neighbor_blocks(memblock);
552 fatal("memory stomping error");
553 }
555 void verify_block(void* memblock) {
556 size_t size = get_size(memblock);
557 if (MallocCushion) {
558 u_char* ptr = (u_char*)memblock - space_before;
559 for (int i = 0; i < MallocCushion; i++) {
560 if (ptr[i] != badResourceValue) {
561 report_heap_error(memblock, ptr+i, "in front of");
562 }
563 }
564 u_char* end = (u_char*)memblock + size + space_after;
565 for (int j = -MallocCushion; j < 0; j++) {
566 if (end[j] != badResourceValue) {
567 report_heap_error(memblock, end+j, "after");
568 }
569 }
570 }
571 }
572 #endif
574 //
575 // This function supports testing of the malloc out of memory
576 // condition without really running the system out of memory.
577 //
578 static u_char* testMalloc(size_t alloc_size) {
579 assert(MallocMaxTestWords > 0, "sanity check");
581 if ((cur_malloc_words + (alloc_size / BytesPerWord)) > MallocMaxTestWords) {
582 return NULL;
583 }
585 u_char* ptr = (u_char*)::malloc(alloc_size);
587 if (ptr != NULL) {
588 Atomic::add(((jint) (alloc_size / BytesPerWord)),
589 (volatile jint *) &cur_malloc_words);
590 }
591 return ptr;
592 }
594 void* os::malloc(size_t size, MEMFLAGS memflags, address caller) {
595 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
596 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
598 if (size == 0) {
599 // return a valid pointer if size is zero
600 // if NULL is returned the calling functions assume out of memory.
601 size = 1;
602 }
604 const size_t alloc_size = size + space_before + space_after;
606 if (size > alloc_size) { // Check for rollover.
607 return NULL;
608 }
610 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
612 u_char* ptr;
614 if (MallocMaxTestWords > 0) {
615 ptr = testMalloc(alloc_size);
616 } else {
617 ptr = (u_char*)::malloc(alloc_size);
618 }
620 #ifdef ASSERT
621 if (ptr == NULL) return NULL;
622 if (MallocCushion) {
623 for (u_char* p = ptr; p < ptr + MallocCushion; p++) *p = (u_char)badResourceValue;
624 u_char* end = ptr + space_before + size;
625 for (u_char* pq = ptr+MallocCushion; pq < end; pq++) *pq = (u_char)uninitBlockPad;
626 for (u_char* q = end; q < end + MallocCushion; q++) *q = (u_char)badResourceValue;
627 }
628 // put size just before data
629 *size_addr_from_base(ptr) = size;
630 #endif
631 u_char* memblock = ptr + space_before;
632 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
633 tty->print_cr("os::malloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, memblock);
634 breakpoint();
635 }
636 debug_only(if (paranoid) verify_block(memblock));
637 if (PrintMalloc && tty != NULL) tty->print_cr("os::malloc " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, memblock);
639 // we do not track MallocCushion memory
640 MemTracker::record_malloc((address)memblock, size, memflags, caller == 0 ? CALLER_PC : caller);
642 return memblock;
643 }
646 void* os::realloc(void *memblock, size_t size, MEMFLAGS memflags, address caller) {
647 #ifndef ASSERT
648 NOT_PRODUCT(inc_stat_counter(&num_mallocs, 1));
649 NOT_PRODUCT(inc_stat_counter(&alloc_bytes, size));
650 void* ptr = ::realloc(memblock, size);
651 if (ptr != NULL) {
652 MemTracker::record_realloc((address)memblock, (address)ptr, size, memflags,
653 caller == 0 ? CALLER_PC : caller);
654 }
655 return ptr;
656 #else
657 if (memblock == NULL) {
658 return malloc(size, memflags, (caller == 0 ? CALLER_PC : caller));
659 }
660 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
661 tty->print_cr("os::realloc caught " PTR_FORMAT, memblock);
662 breakpoint();
663 }
664 verify_block(memblock);
665 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
666 if (size == 0) return NULL;
667 // always move the block
668 void* ptr = malloc(size, memflags, caller == 0 ? CALLER_PC : caller);
669 if (PrintMalloc) tty->print_cr("os::remalloc " SIZE_FORMAT " bytes, " PTR_FORMAT " --> " PTR_FORMAT, size, memblock, ptr);
670 // Copy to new memory if malloc didn't fail
671 if ( ptr != NULL ) {
672 memcpy(ptr, memblock, MIN2(size, get_size(memblock)));
673 if (paranoid) verify_block(ptr);
674 if ((intptr_t)ptr == (intptr_t)MallocCatchPtr) {
675 tty->print_cr("os::realloc caught, " SIZE_FORMAT " bytes --> " PTR_FORMAT, size, ptr);
676 breakpoint();
677 }
678 free(memblock);
679 }
680 return ptr;
681 #endif
682 }
685 void os::free(void *memblock, MEMFLAGS memflags) {
686 NOT_PRODUCT(inc_stat_counter(&num_frees, 1));
687 #ifdef ASSERT
688 if (memblock == NULL) return;
689 if ((intptr_t)memblock == (intptr_t)MallocCatchPtr) {
690 if (tty != NULL) tty->print_cr("os::free caught " PTR_FORMAT, memblock);
691 breakpoint();
692 }
693 verify_block(memblock);
694 NOT_PRODUCT(if (MallocVerifyInterval > 0) check_heap());
695 // Added by detlefs.
696 if (MallocCushion) {
697 u_char* ptr = (u_char*)memblock - space_before;
698 for (u_char* p = ptr; p < ptr + MallocCushion; p++) {
699 guarantee(*p == badResourceValue,
700 "Thing freed should be malloc result.");
701 *p = (u_char)freeBlockPad;
702 }
703 size_t size = get_size(memblock);
704 inc_stat_counter(&free_bytes, size);
705 u_char* end = ptr + space_before + size;
706 for (u_char* q = end; q < end + MallocCushion; q++) {
707 guarantee(*q == badResourceValue,
708 "Thing freed should be malloc result.");
709 *q = (u_char)freeBlockPad;
710 }
711 if (PrintMalloc && tty != NULL)
712 fprintf(stderr, "os::free " SIZE_FORMAT " bytes --> " PTR_FORMAT "\n", size, (uintptr_t)memblock);
713 } else if (PrintMalloc && tty != NULL) {
714 // tty->print_cr("os::free %p", memblock);
715 fprintf(stderr, "os::free " PTR_FORMAT "\n", (uintptr_t)memblock);
716 }
717 #endif
718 MemTracker::record_free((address)memblock, memflags);
720 ::free((char*)memblock - space_before);
721 }
723 void os::init_random(long initval) {
724 _rand_seed = initval;
725 }
728 long os::random() {
729 /* standard, well-known linear congruential random generator with
730 * next_rand = (16807*seed) mod (2**31-1)
731 * see
732 * (1) "Random Number Generators: Good Ones Are Hard to Find",
733 * S.K. Park and K.W. Miller, Communications of the ACM 31:10 (Oct 1988),
734 * (2) "Two Fast Implementations of the 'Minimal Standard' Random
735 * Number Generator", David G. Carta, Comm. ACM 33, 1 (Jan 1990), pp. 87-88.
736 */
737 const long a = 16807;
738 const unsigned long m = 2147483647;
739 const long q = m / a; assert(q == 127773, "weird math");
740 const long r = m % a; assert(r == 2836, "weird math");
742 // compute az=2^31p+q
743 unsigned long lo = a * (long)(_rand_seed & 0xFFFF);
744 unsigned long hi = a * (long)((unsigned long)_rand_seed >> 16);
745 lo += (hi & 0x7FFF) << 16;
747 // if q overflowed, ignore the overflow and increment q
748 if (lo > m) {
749 lo &= m;
750 ++lo;
751 }
752 lo += hi >> 15;
754 // if (p+q) overflowed, ignore the overflow and increment (p+q)
755 if (lo > m) {
756 lo &= m;
757 ++lo;
758 }
759 return (_rand_seed = lo);
760 }
762 // The INITIALIZED state is distinguished from the SUSPENDED state because the
763 // conditions in which a thread is first started are different from those in which
764 // a suspension is resumed. These differences make it hard for us to apply the
765 // tougher checks when starting threads that we want to do when resuming them.
766 // However, when start_thread is called as a result of Thread.start, on a Java
767 // thread, the operation is synchronized on the Java Thread object. So there
768 // cannot be a race to start the thread and hence for the thread to exit while
769 // we are working on it. Non-Java threads that start Java threads either have
770 // to do so in a context in which races are impossible, or should do appropriate
771 // locking.
773 void os::start_thread(Thread* thread) {
774 // guard suspend/resume
775 MutexLockerEx ml(thread->SR_lock(), Mutex::_no_safepoint_check_flag);
776 OSThread* osthread = thread->osthread();
777 osthread->set_state(RUNNABLE);
778 pd_start_thread(thread);
779 }
781 //---------------------------------------------------------------------------
782 // Helper functions for fatal error handler
784 void os::print_hex_dump(outputStream* st, address start, address end, int unitsize) {
785 assert(unitsize == 1 || unitsize == 2 || unitsize == 4 || unitsize == 8, "just checking");
787 int cols = 0;
788 int cols_per_line = 0;
789 switch (unitsize) {
790 case 1: cols_per_line = 16; break;
791 case 2: cols_per_line = 8; break;
792 case 4: cols_per_line = 4; break;
793 case 8: cols_per_line = 2; break;
794 default: return;
795 }
797 address p = start;
798 st->print(PTR_FORMAT ": ", start);
799 while (p < end) {
800 switch (unitsize) {
801 case 1: st->print("%02x", *(u1*)p); break;
802 case 2: st->print("%04x", *(u2*)p); break;
803 case 4: st->print("%08x", *(u4*)p); break;
804 case 8: st->print("%016" FORMAT64_MODIFIER "x", *(u8*)p); break;
805 }
806 p += unitsize;
807 cols++;
808 if (cols >= cols_per_line && p < end) {
809 cols = 0;
810 st->cr();
811 st->print(PTR_FORMAT ": ", p);
812 } else {
813 st->print(" ");
814 }
815 }
816 st->cr();
817 }
819 void os::print_environment_variables(outputStream* st, const char** env_list,
820 char* buffer, int len) {
821 if (env_list) {
822 st->print_cr("Environment Variables:");
824 for (int i = 0; env_list[i] != NULL; i++) {
825 if (getenv(env_list[i], buffer, len)) {
826 st->print(env_list[i]);
827 st->print("=");
828 st->print_cr(buffer);
829 }
830 }
831 }
832 }
834 void os::print_cpu_info(outputStream* st) {
835 // cpu
836 st->print("CPU:");
837 st->print("total %d", os::processor_count());
838 // It's not safe to query number of active processors after crash
839 // st->print("(active %d)", os::active_processor_count());
840 st->print(" %s", VM_Version::cpu_features());
841 st->cr();
842 pd_print_cpu_info(st);
843 }
845 void os::print_date_and_time(outputStream *st) {
846 time_t tloc;
847 (void)time(&tloc);
848 st->print("time: %s", ctime(&tloc)); // ctime adds newline.
850 double t = os::elapsedTime();
851 // NOTE: It tends to crash after a SEGV if we want to printf("%f",...) in
852 // Linux. Must be a bug in glibc ? Workaround is to round "t" to int
853 // before printf. We lost some precision, but who cares?
854 st->print_cr("elapsed time: %d seconds", (int)t);
855 }
857 // moved from debug.cpp (used to be find()) but still called from there
858 // The verbose parameter is only set by the debug code in one case
859 void os::print_location(outputStream* st, intptr_t x, bool verbose) {
860 address addr = (address)x;
861 CodeBlob* b = CodeCache::find_blob_unsafe(addr);
862 if (b != NULL) {
863 if (b->is_buffer_blob()) {
864 // the interpreter is generated into a buffer blob
865 InterpreterCodelet* i = Interpreter::codelet_containing(addr);
866 if (i != NULL) {
867 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an Interpreter codelet", addr, (int)(addr - i->code_begin()));
868 i->print_on(st);
869 return;
870 }
871 if (Interpreter::contains(addr)) {
872 st->print_cr(INTPTR_FORMAT " is pointing into interpreter code"
873 " (not bytecode specific)", addr);
874 return;
875 }
876 //
877 if (AdapterHandlerLibrary::contains(b)) {
878 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in an AdapterHandler", addr, (int)(addr - b->code_begin()));
879 AdapterHandlerLibrary::print_handler_on(st, b);
880 }
881 // the stubroutines are generated into a buffer blob
882 StubCodeDesc* d = StubCodeDesc::desc_for(addr);
883 if (d != NULL) {
884 st->print_cr(INTPTR_FORMAT " is at begin+%d in a stub", addr, (int)(addr - d->begin()));
885 d->print_on(st);
886 st->cr();
887 return;
888 }
889 if (StubRoutines::contains(addr)) {
890 st->print_cr(INTPTR_FORMAT " is pointing to an (unnamed) "
891 "stub routine", addr);
892 return;
893 }
894 // the InlineCacheBuffer is using stubs generated into a buffer blob
895 if (InlineCacheBuffer::contains(addr)) {
896 st->print_cr(INTPTR_FORMAT " is pointing into InlineCacheBuffer", addr);
897 return;
898 }
899 VtableStub* v = VtableStubs::stub_containing(addr);
900 if (v != NULL) {
901 st->print_cr(INTPTR_FORMAT " is at entry_point+%d in a vtable stub", addr, (int)(addr - v->entry_point()));
902 v->print_on(st);
903 st->cr();
904 return;
905 }
906 }
907 nmethod* nm = b->as_nmethod_or_null();
908 if (nm != NULL) {
909 ResourceMark rm;
910 st->print(INTPTR_FORMAT " is at entry_point+%d in (nmethod*)" INTPTR_FORMAT,
911 addr, (int)(addr - nm->entry_point()), nm);
912 if (verbose) {
913 st->print(" for ");
914 nm->method()->print_value_on(st);
915 }
916 st->cr();
917 nm->print_nmethod(verbose);
918 return;
919 }
920 st->print_cr(INTPTR_FORMAT " is at code_begin+%d in ", addr, (int)(addr - b->code_begin()));
921 b->print_on(st);
922 return;
923 }
925 if (Universe::heap()->is_in(addr)) {
926 HeapWord* p = Universe::heap()->block_start(addr);
927 bool print = false;
928 // If we couldn't find it it just may mean that heap wasn't parseable
929 // See if we were just given an oop directly
930 if (p != NULL && Universe::heap()->block_is_obj(p)) {
931 print = true;
932 } else if (p == NULL && ((oopDesc*)addr)->is_oop()) {
933 p = (HeapWord*) addr;
934 print = true;
935 }
936 if (print) {
937 if (p == (HeapWord*) addr) {
938 st->print_cr(INTPTR_FORMAT " is an oop", addr);
939 } else {
940 st->print_cr(INTPTR_FORMAT " is pointing into object: " INTPTR_FORMAT, addr, p);
941 }
942 oop(p)->print_on(st);
943 return;
944 }
945 } else {
946 if (Universe::heap()->is_in_reserved(addr)) {
947 st->print_cr(INTPTR_FORMAT " is an unallocated location "
948 "in the heap", addr);
949 return;
950 }
951 }
952 if (JNIHandles::is_global_handle((jobject) addr)) {
953 st->print_cr(INTPTR_FORMAT " is a global jni handle", addr);
954 return;
955 }
956 if (JNIHandles::is_weak_global_handle((jobject) addr)) {
957 st->print_cr(INTPTR_FORMAT " is a weak global jni handle", addr);
958 return;
959 }
960 #ifndef PRODUCT
961 // we don't keep the block list in product mode
962 if (JNIHandleBlock::any_contains((jobject) addr)) {
963 st->print_cr(INTPTR_FORMAT " is a local jni handle", addr);
964 return;
965 }
966 #endif
968 for(JavaThread *thread = Threads::first(); thread; thread = thread->next()) {
969 // Check for privilege stack
970 if (thread->privileged_stack_top() != NULL &&
971 thread->privileged_stack_top()->contains(addr)) {
972 st->print_cr(INTPTR_FORMAT " is pointing into the privilege stack "
973 "for thread: " INTPTR_FORMAT, addr, thread);
974 if (verbose) thread->print_on(st);
975 return;
976 }
977 // If the addr is a java thread print information about that.
978 if (addr == (address)thread) {
979 if (verbose) {
980 thread->print_on(st);
981 } else {
982 st->print_cr(INTPTR_FORMAT " is a thread", addr);
983 }
984 return;
985 }
986 // If the addr is in the stack region for this thread then report that
987 // and print thread info
988 if (thread->stack_base() >= addr &&
989 addr > (thread->stack_base() - thread->stack_size())) {
990 st->print_cr(INTPTR_FORMAT " is pointing into the stack for thread: "
991 INTPTR_FORMAT, addr, thread);
992 if (verbose) thread->print_on(st);
993 return;
994 }
996 }
998 #ifndef PRODUCT
999 // Check if in metaspace.
1000 if (ClassLoaderDataGraph::contains((address)addr)) {
1001 // Use addr->print() from the debugger instead (not here)
1002 st->print_cr(INTPTR_FORMAT
1003 " is pointing into metadata", addr);
1004 return;
1005 }
1006 #endif
1008 // Try an OS specific find
1009 if (os::find(addr, st)) {
1010 return;
1011 }
1013 st->print_cr(INTPTR_FORMAT " is an unknown value", addr);
1014 }
1016 // Looks like all platforms except IA64 can use the same function to check
1017 // if C stack is walkable beyond current frame. The check for fp() is not
1018 // necessary on Sparc, but it's harmless.
1019 bool os::is_first_C_frame(frame* fr) {
1020 #if defined(IA64) && !defined(_WIN32)
1021 // On IA64 we have to check if the callers bsp is still valid
1022 // (i.e. within the register stack bounds).
1023 // Notice: this only works for threads created by the VM and only if
1024 // we walk the current stack!!! If we want to be able to walk
1025 // arbitrary other threads, we'll have to somehow store the thread
1026 // object in the frame.
1027 Thread *thread = Thread::current();
1028 if ((address)fr->fp() <=
1029 thread->register_stack_base() HPUX_ONLY(+ 0x0) LINUX_ONLY(+ 0x50)) {
1030 // This check is a little hacky, because on Linux the first C
1031 // frame's ('start_thread') register stack frame starts at
1032 // "register_stack_base + 0x48" while on HPUX, the first C frame's
1033 // ('__pthread_bound_body') register stack frame seems to really
1034 // start at "register_stack_base".
1035 return true;
1036 } else {
1037 return false;
1038 }
1039 #elif defined(IA64) && defined(_WIN32)
1040 return true;
1041 #else
1042 // Load up sp, fp, sender sp and sender fp, check for reasonable values.
1043 // Check usp first, because if that's bad the other accessors may fault
1044 // on some architectures. Ditto ufp second, etc.
1045 uintptr_t fp_align_mask = (uintptr_t)(sizeof(address)-1);
1046 // sp on amd can be 32 bit aligned.
1047 uintptr_t sp_align_mask = (uintptr_t)(sizeof(int)-1);
1049 uintptr_t usp = (uintptr_t)fr->sp();
1050 if ((usp & sp_align_mask) != 0) return true;
1052 uintptr_t ufp = (uintptr_t)fr->fp();
1053 if ((ufp & fp_align_mask) != 0) return true;
1055 uintptr_t old_sp = (uintptr_t)fr->sender_sp();
1056 if ((old_sp & sp_align_mask) != 0) return true;
1057 if (old_sp == 0 || old_sp == (uintptr_t)-1) return true;
1059 uintptr_t old_fp = (uintptr_t)fr->link();
1060 if ((old_fp & fp_align_mask) != 0) return true;
1061 if (old_fp == 0 || old_fp == (uintptr_t)-1 || old_fp == ufp) return true;
1063 // stack grows downwards; if old_fp is below current fp or if the stack
1064 // frame is too large, either the stack is corrupted or fp is not saved
1065 // on stack (i.e. on x86, ebp may be used as general register). The stack
1066 // is not walkable beyond current frame.
1067 if (old_fp < ufp) return true;
1068 if (old_fp - ufp > 64 * K) return true;
1070 return false;
1071 #endif
1072 }
1074 #ifdef ASSERT
1075 extern "C" void test_random() {
1076 const double m = 2147483647;
1077 double mean = 0.0, variance = 0.0, t;
1078 long reps = 10000;
1079 unsigned long seed = 1;
1081 tty->print_cr("seed %ld for %ld repeats...", seed, reps);
1082 os::init_random(seed);
1083 long num;
1084 for (int k = 0; k < reps; k++) {
1085 num = os::random();
1086 double u = (double)num / m;
1087 assert(u >= 0.0 && u <= 1.0, "bad random number!");
1089 // calculate mean and variance of the random sequence
1090 mean += u;
1091 variance += (u*u);
1092 }
1093 mean /= reps;
1094 variance /= (reps - 1);
1096 assert(num == 1043618065, "bad seed");
1097 tty->print_cr("mean of the 1st 10000 numbers: %f", mean);
1098 tty->print_cr("variance of the 1st 10000 numbers: %f", variance);
1099 const double eps = 0.0001;
1100 t = fabsd(mean - 0.5018);
1101 assert(t < eps, "bad mean");
1102 t = (variance - 0.3355) < 0.0 ? -(variance - 0.3355) : variance - 0.3355;
1103 assert(t < eps, "bad variance");
1104 }
1105 #endif
1108 // Set up the boot classpath.
1110 char* os::format_boot_path(const char* format_string,
1111 const char* home,
1112 int home_len,
1113 char fileSep,
1114 char pathSep) {
1115 assert((fileSep == '/' && pathSep == ':') ||
1116 (fileSep == '\\' && pathSep == ';'), "unexpected seperator chars");
1118 // Scan the format string to determine the length of the actual
1119 // boot classpath, and handle platform dependencies as well.
1120 int formatted_path_len = 0;
1121 const char* p;
1122 for (p = format_string; *p != 0; ++p) {
1123 if (*p == '%') formatted_path_len += home_len - 1;
1124 ++formatted_path_len;
1125 }
1127 char* formatted_path = NEW_C_HEAP_ARRAY(char, formatted_path_len + 1, mtInternal);
1128 if (formatted_path == NULL) {
1129 return NULL;
1130 }
1132 // Create boot classpath from format, substituting separator chars and
1133 // java home directory.
1134 char* q = formatted_path;
1135 for (p = format_string; *p != 0; ++p) {
1136 switch (*p) {
1137 case '%':
1138 strcpy(q, home);
1139 q += home_len;
1140 break;
1141 case '/':
1142 *q++ = fileSep;
1143 break;
1144 case ':':
1145 *q++ = pathSep;
1146 break;
1147 default:
1148 *q++ = *p;
1149 }
1150 }
1151 *q = '\0';
1153 assert((q - formatted_path) == formatted_path_len, "formatted_path size botched");
1154 return formatted_path;
1155 }
1158 bool os::set_boot_path(char fileSep, char pathSep) {
1159 const char* home = Arguments::get_java_home();
1160 int home_len = (int)strlen(home);
1162 static const char* meta_index_dir_format = "%/lib/";
1163 static const char* meta_index_format = "%/lib/meta-index";
1164 char* meta_index = format_boot_path(meta_index_format, home, home_len, fileSep, pathSep);
1165 if (meta_index == NULL) return false;
1166 char* meta_index_dir = format_boot_path(meta_index_dir_format, home, home_len, fileSep, pathSep);
1167 if (meta_index_dir == NULL) return false;
1168 Arguments::set_meta_index_path(meta_index, meta_index_dir);
1170 // Any modification to the JAR-file list, for the boot classpath must be
1171 // aligned with install/install/make/common/Pack.gmk. Note: boot class
1172 // path class JARs, are stripped for StackMapTable to reduce download size.
1173 static const char classpath_format[] =
1174 "%/lib/resources.jar:"
1175 "%/lib/rt.jar:"
1176 "%/lib/sunrsasign.jar:"
1177 "%/lib/jsse.jar:"
1178 "%/lib/jce.jar:"
1179 "%/lib/charsets.jar:"
1180 "%/lib/jfr.jar:"
1181 #ifdef __APPLE__
1182 "%/lib/JObjC.jar:"
1183 #endif
1184 "%/classes";
1185 char* sysclasspath = format_boot_path(classpath_format, home, home_len, fileSep, pathSep);
1186 if (sysclasspath == NULL) return false;
1187 Arguments::set_sysclasspath(sysclasspath);
1189 return true;
1190 }
1192 /*
1193 * Splits a path, based on its separator, the number of
1194 * elements is returned back in n.
1195 * It is the callers responsibility to:
1196 * a> check the value of n, and n may be 0.
1197 * b> ignore any empty path elements
1198 * c> free up the data.
1199 */
1200 char** os::split_path(const char* path, int* n) {
1201 *n = 0;
1202 if (path == NULL || strlen(path) == 0) {
1203 return NULL;
1204 }
1205 const char psepchar = *os::path_separator();
1206 char* inpath = (char*)NEW_C_HEAP_ARRAY(char, strlen(path) + 1, mtInternal);
1207 if (inpath == NULL) {
1208 return NULL;
1209 }
1210 strcpy(inpath, path);
1211 int count = 1;
1212 char* p = strchr(inpath, psepchar);
1213 // Get a count of elements to allocate memory
1214 while (p != NULL) {
1215 count++;
1216 p++;
1217 p = strchr(p, psepchar);
1218 }
1219 char** opath = (char**) NEW_C_HEAP_ARRAY(char*, count, mtInternal);
1220 if (opath == NULL) {
1221 return NULL;
1222 }
1224 // do the actual splitting
1225 p = inpath;
1226 for (int i = 0 ; i < count ; i++) {
1227 size_t len = strcspn(p, os::path_separator());
1228 if (len > JVM_MAXPATHLEN) {
1229 return NULL;
1230 }
1231 // allocate the string and add terminator storage
1232 char* s = (char*)NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
1233 if (s == NULL) {
1234 return NULL;
1235 }
1236 strncpy(s, p, len);
1237 s[len] = '\0';
1238 opath[i] = s;
1239 p += len + 1;
1240 }
1241 FREE_C_HEAP_ARRAY(char, inpath, mtInternal);
1242 *n = count;
1243 return opath;
1244 }
1246 void os::set_memory_serialize_page(address page) {
1247 int count = log2_intptr(sizeof(class JavaThread)) - log2_intptr(64);
1248 _mem_serialize_page = (volatile int32_t *)page;
1249 // We initialize the serialization page shift count here
1250 // We assume a cache line size of 64 bytes
1251 assert(SerializePageShiftCount == count,
1252 "thread size changed, fix SerializePageShiftCount constant");
1253 set_serialize_page_mask((uintptr_t)(vm_page_size() - sizeof(int32_t)));
1254 }
1256 static volatile intptr_t SerializePageLock = 0;
1258 // This method is called from signal handler when SIGSEGV occurs while the current
1259 // thread tries to store to the "read-only" memory serialize page during state
1260 // transition.
1261 void os::block_on_serialize_page_trap() {
1262 if (TraceSafepoint) {
1263 tty->print_cr("Block until the serialize page permission restored");
1264 }
1265 // When VMThread is holding the SerializePageLock during modifying the
1266 // access permission of the memory serialize page, the following call
1267 // will block until the permission of that page is restored to rw.
1268 // Generally, it is unsafe to manipulate locks in signal handlers, but in
1269 // this case, it's OK as the signal is synchronous and we know precisely when
1270 // it can occur.
1271 Thread::muxAcquire(&SerializePageLock, "set_memory_serialize_page");
1272 Thread::muxRelease(&SerializePageLock);
1273 }
1275 // Serialize all thread state variables
1276 void os::serialize_thread_states() {
1277 // On some platforms such as Solaris & Linux, the time duration of the page
1278 // permission restoration is observed to be much longer than expected due to
1279 // scheduler starvation problem etc. To avoid the long synchronization
1280 // time and expensive page trap spinning, 'SerializePageLock' is used to block
1281 // the mutator thread if such case is encountered. See bug 6546278 for details.
1282 Thread::muxAcquire(&SerializePageLock, "serialize_thread_states");
1283 os::protect_memory((char *)os::get_memory_serialize_page(),
1284 os::vm_page_size(), MEM_PROT_READ);
1285 os::protect_memory((char *)os::get_memory_serialize_page(),
1286 os::vm_page_size(), MEM_PROT_RW);
1287 Thread::muxRelease(&SerializePageLock);
1288 }
1290 // Returns true if the current stack pointer is above the stack shadow
1291 // pages, false otherwise.
1293 bool os::stack_shadow_pages_available(Thread *thread, methodHandle method) {
1294 assert(StackRedPages > 0 && StackYellowPages > 0,"Sanity check");
1295 address sp = current_stack_pointer();
1296 // Check if we have StackShadowPages above the yellow zone. This parameter
1297 // is dependent on the depth of the maximum VM call stack possible from
1298 // the handler for stack overflow. 'instanceof' in the stack overflow
1299 // handler or a println uses at least 8k stack of VM and native code
1300 // respectively.
1301 const int framesize_in_bytes =
1302 Interpreter::size_top_interpreter_activation(method()) * wordSize;
1303 int reserved_area = ((StackShadowPages + StackRedPages + StackYellowPages)
1304 * vm_page_size()) + framesize_in_bytes;
1305 // The very lower end of the stack
1306 address stack_limit = thread->stack_base() - thread->stack_size();
1307 return (sp > (stack_limit + reserved_area));
1308 }
1310 size_t os::page_size_for_region(size_t region_min_size, size_t region_max_size,
1311 uint min_pages)
1312 {
1313 assert(min_pages > 0, "sanity");
1314 if (UseLargePages) {
1315 const size_t max_page_size = region_max_size / min_pages;
1317 for (unsigned int i = 0; _page_sizes[i] != 0; ++i) {
1318 const size_t sz = _page_sizes[i];
1319 const size_t mask = sz - 1;
1320 if ((region_min_size & mask) == 0 && (region_max_size & mask) == 0) {
1321 // The largest page size with no fragmentation.
1322 return sz;
1323 }
1325 if (sz <= max_page_size) {
1326 // The largest page size that satisfies the min_pages requirement.
1327 return sz;
1328 }
1329 }
1330 }
1332 return vm_page_size();
1333 }
1335 #ifndef PRODUCT
1336 void os::trace_page_sizes(const char* str, const size_t* page_sizes, int count)
1337 {
1338 if (TracePageSizes) {
1339 tty->print("%s: ", str);
1340 for (int i = 0; i < count; ++i) {
1341 tty->print(" " SIZE_FORMAT, page_sizes[i]);
1342 }
1343 tty->cr();
1344 }
1345 }
1347 void os::trace_page_sizes(const char* str, const size_t region_min_size,
1348 const size_t region_max_size, const size_t page_size,
1349 const char* base, const size_t size)
1350 {
1351 if (TracePageSizes) {
1352 tty->print_cr("%s: min=" SIZE_FORMAT " max=" SIZE_FORMAT
1353 " pg_sz=" SIZE_FORMAT " base=" PTR_FORMAT
1354 " size=" SIZE_FORMAT,
1355 str, region_min_size, region_max_size,
1356 page_size, base, size);
1357 }
1358 }
1359 #endif // #ifndef PRODUCT
1361 // This is the working definition of a server class machine:
1362 // >= 2 physical CPU's and >=2GB of memory, with some fuzz
1363 // because the graphics memory (?) sometimes masks physical memory.
1364 // If you want to change the definition of a server class machine
1365 // on some OS or platform, e.g., >=4GB on Windohs platforms,
1366 // then you'll have to parameterize this method based on that state,
1367 // as was done for logical processors here, or replicate and
1368 // specialize this method for each platform. (Or fix os to have
1369 // some inheritance structure and use subclassing. Sigh.)
1370 // If you want some platform to always or never behave as a server
1371 // class machine, change the setting of AlwaysActAsServerClassMachine
1372 // and NeverActAsServerClassMachine in globals*.hpp.
1373 bool os::is_server_class_machine() {
1374 // First check for the early returns
1375 if (NeverActAsServerClassMachine) {
1376 return false;
1377 }
1378 if (AlwaysActAsServerClassMachine) {
1379 return true;
1380 }
1381 // Then actually look at the machine
1382 bool result = false;
1383 const unsigned int server_processors = 2;
1384 const julong server_memory = 2UL * G;
1385 // We seem not to get our full complement of memory.
1386 // We allow some part (1/8?) of the memory to be "missing",
1387 // based on the sizes of DIMMs, and maybe graphics cards.
1388 const julong missing_memory = 256UL * M;
1390 /* Is this a server class machine? */
1391 if ((os::active_processor_count() >= (int)server_processors) &&
1392 (os::physical_memory() >= (server_memory - missing_memory))) {
1393 const unsigned int logical_processors =
1394 VM_Version::logical_processors_per_package();
1395 if (logical_processors > 1) {
1396 const unsigned int physical_packages =
1397 os::active_processor_count() / logical_processors;
1398 if (physical_packages > server_processors) {
1399 result = true;
1400 }
1401 } else {
1402 result = true;
1403 }
1404 }
1405 return result;
1406 }
1408 // Read file line by line, if line is longer than bsize,
1409 // skip rest of line.
1410 int os::get_line_chars(int fd, char* buf, const size_t bsize){
1411 size_t sz, i = 0;
1413 // read until EOF, EOL or buf is full
1414 while ((sz = (int) read(fd, &buf[i], 1)) == 1 && i < (bsize-2) && buf[i] != '\n') {
1415 ++i;
1416 }
1418 if (buf[i] == '\n') {
1419 // EOL reached so ignore EOL character and return
1421 buf[i] = 0;
1422 return (int) i;
1423 }
1425 buf[i+1] = 0;
1427 if (sz != 1) {
1428 // EOF reached. if we read chars before EOF return them and
1429 // return EOF on next call otherwise return EOF
1431 return (i == 0) ? -1 : (int) i;
1432 }
1434 // line is longer than size of buf, skip to EOL
1435 char ch;
1436 while (read(fd, &ch, 1) == 1 && ch != '\n') {
1437 // Do nothing
1438 }
1440 // return initial part of line that fits in buf.
1441 // If we reached EOF, it will be returned on next call.
1443 return (int) i;
1444 }
1446 void os::SuspendedThreadTask::run() {
1447 assert(Threads_lock->owned_by_self() || (_thread == VMThread::vm_thread()), "must have threads lock to call this");
1448 internal_do_task();
1449 _done = true;
1450 }
1452 bool os::create_stack_guard_pages(char* addr, size_t bytes) {
1453 return os::pd_create_stack_guard_pages(addr, bytes);
1454 }
1456 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint) {
1457 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1458 if (result != NULL) {
1459 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1460 }
1462 return result;
1463 }
1465 char* os::reserve_memory(size_t bytes, char* addr, size_t alignment_hint,
1466 MEMFLAGS flags) {
1467 char* result = pd_reserve_memory(bytes, addr, alignment_hint);
1468 if (result != NULL) {
1469 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1470 MemTracker::record_virtual_memory_type((address)result, flags);
1471 }
1473 return result;
1474 }
1476 char* os::attempt_reserve_memory_at(size_t bytes, char* addr) {
1477 char* result = pd_attempt_reserve_memory_at(bytes, addr);
1478 if (result != NULL) {
1479 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1480 }
1481 return result;
1482 }
1484 void os::split_reserved_memory(char *base, size_t size,
1485 size_t split, bool realloc) {
1486 pd_split_reserved_memory(base, size, split, realloc);
1487 }
1489 bool os::commit_memory(char* addr, size_t bytes, bool executable) {
1490 bool res = pd_commit_memory(addr, bytes, executable);
1491 if (res) {
1492 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1493 }
1494 return res;
1495 }
1497 bool os::commit_memory(char* addr, size_t size, size_t alignment_hint,
1498 bool executable) {
1499 bool res = os::pd_commit_memory(addr, size, alignment_hint, executable);
1500 if (res) {
1501 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1502 }
1503 return res;
1504 }
1506 void os::commit_memory_or_exit(char* addr, size_t bytes, bool executable,
1507 const char* mesg) {
1508 pd_commit_memory_or_exit(addr, bytes, executable, mesg);
1509 MemTracker::record_virtual_memory_commit((address)addr, bytes, CALLER_PC);
1510 }
1512 void os::commit_memory_or_exit(char* addr, size_t size, size_t alignment_hint,
1513 bool executable, const char* mesg) {
1514 os::pd_commit_memory_or_exit(addr, size, alignment_hint, executable, mesg);
1515 MemTracker::record_virtual_memory_commit((address)addr, size, CALLER_PC);
1516 }
1518 bool os::uncommit_memory(char* addr, size_t bytes) {
1519 bool res = pd_uncommit_memory(addr, bytes);
1520 if (res) {
1521 MemTracker::record_virtual_memory_uncommit((address)addr, bytes);
1522 }
1523 return res;
1524 }
1526 bool os::release_memory(char* addr, size_t bytes) {
1527 bool res = pd_release_memory(addr, bytes);
1528 if (res) {
1529 MemTracker::record_virtual_memory_release((address)addr, bytes);
1530 }
1531 return res;
1532 }
1535 char* os::map_memory(int fd, const char* file_name, size_t file_offset,
1536 char *addr, size_t bytes, bool read_only,
1537 bool allow_exec) {
1538 char* result = pd_map_memory(fd, file_name, file_offset, addr, bytes, read_only, allow_exec);
1539 if (result != NULL) {
1540 MemTracker::record_virtual_memory_reserve((address)result, bytes, CALLER_PC);
1541 MemTracker::record_virtual_memory_commit((address)result, bytes, CALLER_PC);
1542 }
1543 return result;
1544 }
1546 char* os::remap_memory(int fd, const char* file_name, size_t file_offset,
1547 char *addr, size_t bytes, bool read_only,
1548 bool allow_exec) {
1549 return pd_remap_memory(fd, file_name, file_offset, addr, bytes,
1550 read_only, allow_exec);
1551 }
1553 bool os::unmap_memory(char *addr, size_t bytes) {
1554 bool result = pd_unmap_memory(addr, bytes);
1555 if (result) {
1556 MemTracker::record_virtual_memory_uncommit((address)addr, bytes);
1557 MemTracker::record_virtual_memory_release((address)addr, bytes);
1558 }
1559 return result;
1560 }
1562 void os::free_memory(char *addr, size_t bytes, size_t alignment_hint) {
1563 pd_free_memory(addr, bytes, alignment_hint);
1564 }
1566 void os::realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
1567 pd_realign_memory(addr, bytes, alignment_hint);
1568 }
1570 #ifndef TARGET_OS_FAMILY_windows
1571 /* try to switch state from state "from" to state "to"
1572 * returns the state set after the method is complete
1573 */
1574 os::SuspendResume::State os::SuspendResume::switch_state(os::SuspendResume::State from,
1575 os::SuspendResume::State to)
1576 {
1577 os::SuspendResume::State result =
1578 (os::SuspendResume::State) Atomic::cmpxchg((jint) to, (jint *) &_state, (jint) from);
1579 if (result == from) {
1580 // success
1581 return to;
1582 }
1583 return result;
1584 }
1585 #endif