1 /*
2 * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 // Must be at least Windows Vista or Server 2008 to use InitOnceExecuteOnce
26 #define _WIN32_WINNT 0x0600
27
28 // no precompiled headers
29 #include "classfile/classLoader.hpp"
30 #include "classfile/systemDictionary.hpp"
31 #include "classfile/vmSymbols.hpp"
32 #include "code/icBuffer.hpp"
33 #include "code/vtableStubs.hpp"
34 #include "compiler/compileBroker.hpp"
35 #include "compiler/disassembler.hpp"
36 #include "interpreter/interpreter.hpp"
37 #include "jvm_windows.h"
38 #include "logging/log.hpp"
39 #include "memory/allocation.inline.hpp"
40 #include "memory/filemap.hpp"
41 #include "oops/oop.inline.hpp"
42 #include "os_share_windows.hpp"
43 #include "os_windows.inline.hpp"
44 #include "prims/jniFastGetField.hpp"
45 #include "prims/jvm.h"
46 #include "prims/jvm_misc.hpp"
47 #include "runtime/arguments.hpp"
48 #include "runtime/atomic.hpp"
49 #include "runtime/extendedPC.hpp"
50 #include "runtime/globals.hpp"
51 #include "runtime/interfaceSupport.hpp"
52 #include "runtime/java.hpp"
53 #include "runtime/javaCalls.hpp"
54 #include "runtime/mutexLocker.hpp"
55 #include "runtime/objectMonitor.hpp"
56 #include "runtime/orderAccess.inline.hpp"
57 #include "runtime/osThread.hpp"
58 #include "runtime/perfMemory.hpp"
59 #include "runtime/sharedRuntime.hpp"
60 #include "runtime/statSampler.hpp"
61 #include "runtime/stubRoutines.hpp"
62 #include "runtime/thread.inline.hpp"
63 #include "runtime/threadCritical.hpp"
64 #include "runtime/timer.hpp"
65 #include "runtime/vm_version.hpp"
66 #include "semaphore_windows.hpp"
67 #include "services/attachListener.hpp"
68 #include "services/memTracker.hpp"
69 #include "services/runtimeService.hpp"
70 #include "utilities/align.hpp"
71 #include "utilities/decoder.hpp"
72 #include "utilities/defaultStream.hpp"
73 #include "utilities/events.hpp"
74 #include "utilities/growableArray.hpp"
75 #include "utilities/macros.hpp"
76 #include "utilities/vmError.hpp"
77 #include "windbghelp.hpp"
78
79
80 #ifdef _DEBUG
81 #include <crtdbg.h>
82 #endif
83
84
85 #include <windows.h>
86 #include <sys/types.h>
87 #include <sys/stat.h>
88 #include <sys/timeb.h>
89 #include <objidl.h>
90 #include <shlobj.h>
91
92 #include <malloc.h>
93 #include <signal.h>
94 #include <direct.h>
95 #include <errno.h>
96 #include <fcntl.h>
97 #include <io.h>
98 #include <process.h> // For _beginthreadex(), _endthreadex()
99 #include <imagehlp.h> // For os::dll_address_to_function_name
100 // for enumerating dll libraries
101 #include <vdmdbg.h>
102
103 // for timer info max values which include all bits
104 #define ALL_64_BITS CONST64(-1)
105
106 // For DLL loading/load error detection
107 // Values of PE COFF
108 #define IMAGE_FILE_PTR_TO_SIGNATURE 0x3c
109 #define IMAGE_FILE_SIGNATURE_LENGTH 4
110
111 static HANDLE main_process;
112 static HANDLE main_thread;
113 static int main_thread_id;
114
115 static FILETIME process_creation_time;
116 static FILETIME process_exit_time;
117 static FILETIME process_user_time;
118 static FILETIME process_kernel_time;
119
120 #ifdef _M_AMD64
121 #define __CPU__ amd64
122 #else
123 #define __CPU__ i486
124 #endif
125
126 // save DLL module handle, used by GetModuleFileName
127
128 HINSTANCE vm_lib_handle;
129
130 BOOL WINAPI DllMain(HINSTANCE hinst, DWORD reason, LPVOID reserved) {
131 switch (reason) {
132 case DLL_PROCESS_ATTACH:
133 vm_lib_handle = hinst;
134 if (ForceTimeHighResolution) {
135 timeBeginPeriod(1L);
136 }
137 break;
138 case DLL_PROCESS_DETACH:
139 if (ForceTimeHighResolution) {
140 timeEndPeriod(1L);
141 }
142 break;
143 default:
144 break;
145 }
146 return true;
147 }
148
149 static inline double fileTimeAsDouble(FILETIME* time) {
150 const double high = (double) ((unsigned int) ~0);
151 const double split = 10000000.0;
152 double result = (time->dwLowDateTime / split) +
153 time->dwHighDateTime * (high/split);
154 return result;
155 }
156
157 // Implementation of os
158
159 bool os::unsetenv(const char* name) {
160 assert(name != NULL, "Null pointer");
161 return (SetEnvironmentVariable(name, NULL) == TRUE);
162 }
163
164 // No setuid programs under Windows.
165 bool os::have_special_privileges() {
166 return false;
167 }
168
169
170 // This method is a periodic task to check for misbehaving JNI applications
171 // under CheckJNI, we can add any periodic checks here.
172 // For Windows at the moment does nothing
173 void os::run_periodic_checks() {
174 return;
175 }
176
177 // previous UnhandledExceptionFilter, if there is one
178 static LPTOP_LEVEL_EXCEPTION_FILTER prev_uef_handler = NULL;
179
180 LONG WINAPI Handle_FLT_Exception(struct _EXCEPTION_POINTERS* exceptionInfo);
181
182 void os::init_system_properties_values() {
183 // sysclasspath, java_home, dll_dir
184 {
185 char *home_path;
186 char *dll_path;
187 char *pslash;
188 char *bin = "\\bin";
189 char home_dir[MAX_PATH + 1];
190 char *alt_home_dir = ::getenv("_ALT_JAVA_HOME_DIR");
191
192 if (alt_home_dir != NULL) {
193 strncpy(home_dir, alt_home_dir, MAX_PATH + 1);
194 home_dir[MAX_PATH] = '\0';
195 } else {
196 os::jvm_path(home_dir, sizeof(home_dir));
197 // Found the full path to jvm.dll.
198 // Now cut the path to <java_home>/jre if we can.
199 *(strrchr(home_dir, '\\')) = '\0'; // get rid of \jvm.dll
200 pslash = strrchr(home_dir, '\\');
201 if (pslash != NULL) {
202 *pslash = '\0'; // get rid of \{client|server}
203 pslash = strrchr(home_dir, '\\');
204 if (pslash != NULL) {
205 *pslash = '\0'; // get rid of \bin
206 }
207 }
208 }
209
210 home_path = NEW_C_HEAP_ARRAY(char, strlen(home_dir) + 1, mtInternal);
211 if (home_path == NULL) {
212 return;
213 }
214 strcpy(home_path, home_dir);
215 Arguments::set_java_home(home_path);
216 FREE_C_HEAP_ARRAY(char, home_path);
217
218 dll_path = NEW_C_HEAP_ARRAY(char, strlen(home_dir) + strlen(bin) + 1,
219 mtInternal);
220 if (dll_path == NULL) {
221 return;
222 }
223 strcpy(dll_path, home_dir);
224 strcat(dll_path, bin);
225 Arguments::set_dll_dir(dll_path);
226 FREE_C_HEAP_ARRAY(char, dll_path);
227
228 if (!set_boot_path('\\', ';')) {
229 return;
230 }
231 }
232
233 // library_path
234 #define EXT_DIR "\\lib\\ext"
235 #define BIN_DIR "\\bin"
236 #define PACKAGE_DIR "\\Sun\\Java"
237 {
238 // Win32 library search order (See the documentation for LoadLibrary):
239 //
240 // 1. The directory from which application is loaded.
241 // 2. The system wide Java Extensions directory (Java only)
242 // 3. System directory (GetSystemDirectory)
243 // 4. Windows directory (GetWindowsDirectory)
244 // 5. The PATH environment variable
245 // 6. The current directory
246
247 char *library_path;
248 char tmp[MAX_PATH];
249 char *path_str = ::getenv("PATH");
250
251 library_path = NEW_C_HEAP_ARRAY(char, MAX_PATH * 5 + sizeof(PACKAGE_DIR) +
252 sizeof(BIN_DIR) + (path_str ? strlen(path_str) : 0) + 10, mtInternal);
253
254 library_path[0] = '\0';
255
256 GetModuleFileName(NULL, tmp, sizeof(tmp));
257 *(strrchr(tmp, '\\')) = '\0';
258 strcat(library_path, tmp);
259
260 GetWindowsDirectory(tmp, sizeof(tmp));
261 strcat(library_path, ";");
262 strcat(library_path, tmp);
263 strcat(library_path, PACKAGE_DIR BIN_DIR);
264
265 GetSystemDirectory(tmp, sizeof(tmp));
266 strcat(library_path, ";");
267 strcat(library_path, tmp);
268
269 GetWindowsDirectory(tmp, sizeof(tmp));
270 strcat(library_path, ";");
271 strcat(library_path, tmp);
272
273 if (path_str) {
274 strcat(library_path, ";");
275 strcat(library_path, path_str);
276 }
277
278 strcat(library_path, ";.");
279
280 Arguments::set_library_path(library_path);
281 FREE_C_HEAP_ARRAY(char, library_path);
282 }
283
284 // Default extensions directory
285 {
286 char path[MAX_PATH];
287 char buf[2 * MAX_PATH + 2 * sizeof(EXT_DIR) + sizeof(PACKAGE_DIR) + 1];
288 GetWindowsDirectory(path, MAX_PATH);
289 sprintf(buf, "%s%s;%s%s%s", Arguments::get_java_home(), EXT_DIR,
290 path, PACKAGE_DIR, EXT_DIR);
291 Arguments::set_ext_dirs(buf);
292 }
293 #undef EXT_DIR
294 #undef BIN_DIR
295 #undef PACKAGE_DIR
296
297 #ifndef _WIN64
298 // set our UnhandledExceptionFilter and save any previous one
299 prev_uef_handler = SetUnhandledExceptionFilter(Handle_FLT_Exception);
300 #endif
301
302 // Done
303 return;
304 }
305
306 void os::breakpoint() {
307 DebugBreak();
308 }
309
310 // Invoked from the BREAKPOINT Macro
311 extern "C" void breakpoint() {
312 os::breakpoint();
313 }
314
315 // RtlCaptureStackBackTrace Windows API may not exist prior to Windows XP.
316 // So far, this method is only used by Native Memory Tracking, which is
317 // only supported on Windows XP or later.
318 //
319 int os::get_native_stack(address* stack, int frames, int toSkip) {
320 int captured = RtlCaptureStackBackTrace(toSkip + 1, frames, (PVOID*)stack, NULL);
321 for (int index = captured; index < frames; index ++) {
322 stack[index] = NULL;
323 }
324 return captured;
325 }
326
327
328 // os::current_stack_base()
329 //
330 // Returns the base of the stack, which is the stack's
331 // starting address. This function must be called
332 // while running on the stack of the thread being queried.
333
334 address os::current_stack_base() {
335 MEMORY_BASIC_INFORMATION minfo;
336 address stack_bottom;
337 size_t stack_size;
338
339 VirtualQuery(&minfo, &minfo, sizeof(minfo));
340 stack_bottom = (address)minfo.AllocationBase;
341 stack_size = minfo.RegionSize;
342
343 // Add up the sizes of all the regions with the same
344 // AllocationBase.
345 while (1) {
346 VirtualQuery(stack_bottom+stack_size, &minfo, sizeof(minfo));
347 if (stack_bottom == (address)minfo.AllocationBase) {
348 stack_size += minfo.RegionSize;
349 } else {
350 break;
351 }
352 }
353 return stack_bottom + stack_size;
354 }
355
356 size_t os::current_stack_size() {
357 size_t sz;
358 MEMORY_BASIC_INFORMATION minfo;
359 VirtualQuery(&minfo, &minfo, sizeof(minfo));
360 sz = (size_t)os::current_stack_base() - (size_t)minfo.AllocationBase;
361 return sz;
362 }
363
364 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
365 const struct tm* time_struct_ptr = localtime(clock);
366 if (time_struct_ptr != NULL) {
367 *res = *time_struct_ptr;
368 return res;
369 }
370 return NULL;
371 }
372
373 struct tm* os::gmtime_pd(const time_t* clock, struct tm* res) {
374 const struct tm* time_struct_ptr = gmtime(clock);
375 if (time_struct_ptr != NULL) {
376 *res = *time_struct_ptr;
377 return res;
378 }
379 return NULL;
380 }
381
382 LONG WINAPI topLevelExceptionFilter(struct _EXCEPTION_POINTERS* exceptionInfo);
383
384 // Thread start routine for all newly created threads
385 static unsigned __stdcall thread_native_entry(Thread* thread) {
386 // Try to randomize the cache line index of hot stack frames.
387 // This helps when threads of the same stack traces evict each other's
388 // cache lines. The threads can be either from the same JVM instance, or
389 // from different JVM instances. The benefit is especially true for
390 // processors with hyperthreading technology.
391 static int counter = 0;
392 int pid = os::current_process_id();
393 _alloca(((pid ^ counter++) & 7) * 128);
394
395 thread->initialize_thread_current();
396
397 OSThread* osthr = thread->osthread();
398 assert(osthr->get_state() == RUNNABLE, "invalid os thread state");
399
400 if (UseNUMA) {
401 int lgrp_id = os::numa_get_group_id();
402 if (lgrp_id != -1) {
403 thread->set_lgrp_id(lgrp_id);
404 }
405 }
406
407 // Diagnostic code to investigate JDK-6573254
408 int res = 30115; // non-java thread
409 if (thread->is_Java_thread()) {
410 res = 20115; // java thread
411 }
412
413 log_info(os, thread)("Thread is alive (tid: " UINTX_FORMAT ").", os::current_thread_id());
414
415 // Install a win32 structured exception handler around every thread created
416 // by VM, so VM can generate error dump when an exception occurred in non-
417 // Java thread (e.g. VM thread).
418 __try {
419 thread->run();
420 } __except(topLevelExceptionFilter(
421 (_EXCEPTION_POINTERS*)_exception_info())) {
422 // Nothing to do.
423 }
424
425 log_info(os, thread)("Thread finished (tid: " UINTX_FORMAT ").", os::current_thread_id());
426
427 // One less thread is executing
428 // When the VMThread gets here, the main thread may have already exited
429 // which frees the CodeHeap containing the Atomic::add code
430 if (thread != VMThread::vm_thread() && VMThread::vm_thread() != NULL) {
431 Atomic::dec_ptr((intptr_t*)&os::win32::_os_thread_count);
432 }
433
434 // If a thread has not deleted itself ("delete this") as part of its
435 // termination sequence, we have to ensure thread-local-storage is
436 // cleared before we actually terminate. No threads should ever be
437 // deleted asynchronously with respect to their termination.
438 if (Thread::current_or_null_safe() != NULL) {
439 assert(Thread::current_or_null_safe() == thread, "current thread is wrong");
440 thread->clear_thread_current();
441 }
442
443 // Thread must not return from exit_process_or_thread(), but if it does,
444 // let it proceed to exit normally
445 return (unsigned)os::win32::exit_process_or_thread(os::win32::EPT_THREAD, res);
446 }
447
448 static OSThread* create_os_thread(Thread* thread, HANDLE thread_handle,
449 int thread_id) {
450 // Allocate the OSThread object
451 OSThread* osthread = new OSThread(NULL, NULL);
452 if (osthread == NULL) return NULL;
453
454 // Initialize support for Java interrupts
455 HANDLE interrupt_event = CreateEvent(NULL, true, false, NULL);
456 if (interrupt_event == NULL) {
457 delete osthread;
458 return NULL;
459 }
460 osthread->set_interrupt_event(interrupt_event);
461
462 // Store info on the Win32 thread into the OSThread
463 osthread->set_thread_handle(thread_handle);
464 osthread->set_thread_id(thread_id);
465
466 if (UseNUMA) {
467 int lgrp_id = os::numa_get_group_id();
468 if (lgrp_id != -1) {
469 thread->set_lgrp_id(lgrp_id);
470 }
471 }
472
473 // Initial thread state is INITIALIZED, not SUSPENDED
474 osthread->set_state(INITIALIZED);
475
476 return osthread;
477 }
478
479
480 bool os::create_attached_thread(JavaThread* thread) {
481 #ifdef ASSERT
482 thread->verify_not_published();
483 #endif
484 HANDLE thread_h;
485 if (!DuplicateHandle(main_process, GetCurrentThread(), GetCurrentProcess(),
486 &thread_h, THREAD_ALL_ACCESS, false, 0)) {
487 fatal("DuplicateHandle failed\n");
488 }
489 OSThread* osthread = create_os_thread(thread, thread_h,
490 (int)current_thread_id());
491 if (osthread == NULL) {
492 return false;
493 }
494
495 // Initial thread state is RUNNABLE
496 osthread->set_state(RUNNABLE);
497
498 thread->set_osthread(osthread);
499
500 log_info(os, thread)("Thread attached (tid: " UINTX_FORMAT ").",
501 os::current_thread_id());
502
503 return true;
504 }
505
506 bool os::create_main_thread(JavaThread* thread) {
507 #ifdef ASSERT
508 thread->verify_not_published();
509 #endif
510 if (_starting_thread == NULL) {
511 _starting_thread = create_os_thread(thread, main_thread, main_thread_id);
512 if (_starting_thread == NULL) {
513 return false;
514 }
515 }
516
517 // The primordial thread is runnable from the start)
518 _starting_thread->set_state(RUNNABLE);
519
520 thread->set_osthread(_starting_thread);
521 return true;
522 }
523
524 // Helper function to trace _beginthreadex attributes,
525 // similar to os::Posix::describe_pthread_attr()
526 static char* describe_beginthreadex_attributes(char* buf, size_t buflen,
527 size_t stacksize, unsigned initflag) {
528 stringStream ss(buf, buflen);
529 if (stacksize == 0) {
530 ss.print("stacksize: default, ");
531 } else {
532 ss.print("stacksize: " SIZE_FORMAT "k, ", stacksize / 1024);
533 }
534 ss.print("flags: ");
535 #define PRINT_FLAG(f) if (initflag & f) ss.print( #f " ");
536 #define ALL(X) \
537 X(CREATE_SUSPENDED) \
538 X(STACK_SIZE_PARAM_IS_A_RESERVATION)
539 ALL(PRINT_FLAG)
540 #undef ALL
541 #undef PRINT_FLAG
542 return buf;
543 }
544
545 // Allocate and initialize a new OSThread
546 bool os::create_thread(Thread* thread, ThreadType thr_type,
547 size_t stack_size) {
548 unsigned thread_id;
549
550 // Allocate the OSThread object
551 OSThread* osthread = new OSThread(NULL, NULL);
552 if (osthread == NULL) {
553 return false;
554 }
555
556 // Initialize support for Java interrupts
557 HANDLE interrupt_event = CreateEvent(NULL, true, false, NULL);
558 if (interrupt_event == NULL) {
559 delete osthread;
560 return NULL;
561 }
562 osthread->set_interrupt_event(interrupt_event);
563 osthread->set_interrupted(false);
564
565 thread->set_osthread(osthread);
566
567 if (stack_size == 0) {
568 switch (thr_type) {
569 case os::java_thread:
570 // Java threads use ThreadStackSize which default value can be changed with the flag -Xss
571 if (JavaThread::stack_size_at_create() > 0) {
572 stack_size = JavaThread::stack_size_at_create();
573 }
574 break;
575 case os::compiler_thread:
576 if (CompilerThreadStackSize > 0) {
577 stack_size = (size_t)(CompilerThreadStackSize * K);
578 break;
579 } // else fall through:
580 // use VMThreadStackSize if CompilerThreadStackSize is not defined
581 case os::vm_thread:
582 case os::pgc_thread:
583 case os::cgc_thread:
584 case os::watcher_thread:
585 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K);
586 break;
587 }
588 }
589
590 // Create the Win32 thread
591 //
592 // Contrary to what MSDN document says, "stack_size" in _beginthreadex()
593 // does not specify stack size. Instead, it specifies the size of
594 // initially committed space. The stack size is determined by
595 // PE header in the executable. If the committed "stack_size" is larger
596 // than default value in the PE header, the stack is rounded up to the
597 // nearest multiple of 1MB. For example if the launcher has default
598 // stack size of 320k, specifying any size less than 320k does not
599 // affect the actual stack size at all, it only affects the initial
600 // commitment. On the other hand, specifying 'stack_size' larger than
601 // default value may cause significant increase in memory usage, because
602 // not only the stack space will be rounded up to MB, but also the
603 // entire space is committed upfront.
604 //
605 // Finally Windows XP added a new flag 'STACK_SIZE_PARAM_IS_A_RESERVATION'
606 // for CreateThread() that can treat 'stack_size' as stack size. However we
607 // are not supposed to call CreateThread() directly according to MSDN
608 // document because JVM uses C runtime library. The good news is that the
609 // flag appears to work with _beginthredex() as well.
610
611 const unsigned initflag = CREATE_SUSPENDED | STACK_SIZE_PARAM_IS_A_RESERVATION;
612 HANDLE thread_handle =
613 (HANDLE)_beginthreadex(NULL,
614 (unsigned)stack_size,
615 (unsigned (__stdcall *)(void*)) thread_native_entry,
616 thread,
617 initflag,
618 &thread_id);
619
620 char buf[64];
621 if (thread_handle != NULL) {
622 log_info(os, thread)("Thread started (tid: %u, attributes: %s)",
623 thread_id, describe_beginthreadex_attributes(buf, sizeof(buf), stack_size, initflag));
624 } else {
625 log_warning(os, thread)("Failed to start thread - _beginthreadex failed (%s) for attributes: %s.",
626 os::errno_name(errno), describe_beginthreadex_attributes(buf, sizeof(buf), stack_size, initflag));
627 }
628
629 if (thread_handle == NULL) {
630 // Need to clean up stuff we've allocated so far
631 CloseHandle(osthread->interrupt_event());
632 thread->set_osthread(NULL);
633 delete osthread;
634 return NULL;
635 }
636
637 Atomic::inc_ptr((intptr_t*)&os::win32::_os_thread_count);
638
639 // Store info on the Win32 thread into the OSThread
640 osthread->set_thread_handle(thread_handle);
641 osthread->set_thread_id(thread_id);
642
643 // Initial thread state is INITIALIZED, not SUSPENDED
644 osthread->set_state(INITIALIZED);
645
646 // The thread is returned suspended (in state INITIALIZED), and is started higher up in the call chain
647 return true;
648 }
649
650
651 // Free Win32 resources related to the OSThread
652 void os::free_thread(OSThread* osthread) {
653 assert(osthread != NULL, "osthread not set");
654
655 // We are told to free resources of the argument thread,
656 // but we can only really operate on the current thread.
657 assert(Thread::current()->osthread() == osthread,
658 "os::free_thread but not current thread");
659
660 CloseHandle(osthread->thread_handle());
661 CloseHandle(osthread->interrupt_event());
662 delete osthread;
663 }
664
665 static jlong first_filetime;
666 static jlong initial_performance_count;
667 static jlong performance_frequency;
668
669
670 jlong as_long(LARGE_INTEGER x) {
671 jlong result = 0; // initialization to avoid warning
672 set_high(&result, x.HighPart);
673 set_low(&result, x.LowPart);
674 return result;
675 }
676
677
678 jlong os::elapsed_counter() {
679 LARGE_INTEGER count;
680 QueryPerformanceCounter(&count);
681 return as_long(count) - initial_performance_count;
682 }
683
684
685 jlong os::elapsed_frequency() {
686 return performance_frequency;
687 }
688
689
690 julong os::available_memory() {
691 return win32::available_memory();
692 }
693
694 julong os::win32::available_memory() {
695 // Use GlobalMemoryStatusEx() because GlobalMemoryStatus() may return incorrect
696 // value if total memory is larger than 4GB
697 MEMORYSTATUSEX ms;
698 ms.dwLength = sizeof(ms);
699 GlobalMemoryStatusEx(&ms);
700
701 return (julong)ms.ullAvailPhys;
702 }
703
704 julong os::physical_memory() {
705 return win32::physical_memory();
706 }
707
708 bool os::has_allocatable_memory_limit(julong* limit) {
709 MEMORYSTATUSEX ms;
710 ms.dwLength = sizeof(ms);
711 GlobalMemoryStatusEx(&ms);
712 #ifdef _LP64
713 *limit = (julong)ms.ullAvailVirtual;
714 return true;
715 #else
716 // Limit to 1400m because of the 2gb address space wall
717 *limit = MIN2((julong)1400*M, (julong)ms.ullAvailVirtual);
718 return true;
719 #endif
720 }
721
722 int os::active_processor_count() {
723 DWORD_PTR lpProcessAffinityMask = 0;
724 DWORD_PTR lpSystemAffinityMask = 0;
725 int proc_count = processor_count();
726 if (proc_count <= sizeof(UINT_PTR) * BitsPerByte &&
727 GetProcessAffinityMask(GetCurrentProcess(), &lpProcessAffinityMask, &lpSystemAffinityMask)) {
728 // Nof active processors is number of bits in process affinity mask
729 int bitcount = 0;
730 while (lpProcessAffinityMask != 0) {
731 lpProcessAffinityMask = lpProcessAffinityMask & (lpProcessAffinityMask-1);
732 bitcount++;
733 }
734 return bitcount;
735 } else {
736 return proc_count;
737 }
738 }
739
740 void os::set_native_thread_name(const char *name) {
741
742 // See: http://msdn.microsoft.com/en-us/library/xcb2z8hs.aspx
743 //
744 // Note that unfortunately this only works if the process
745 // is already attached to a debugger; debugger must observe
746 // the exception below to show the correct name.
747
748 // If there is no debugger attached skip raising the exception
749 if (!IsDebuggerPresent()) {
750 return;
751 }
752
753 const DWORD MS_VC_EXCEPTION = 0x406D1388;
754 struct {
755 DWORD dwType; // must be 0x1000
756 LPCSTR szName; // pointer to name (in user addr space)
757 DWORD dwThreadID; // thread ID (-1=caller thread)
758 DWORD dwFlags; // reserved for future use, must be zero
759 } info;
760
761 info.dwType = 0x1000;
762 info.szName = name;
763 info.dwThreadID = -1;
764 info.dwFlags = 0;
765
766 __try {
767 RaiseException (MS_VC_EXCEPTION, 0, sizeof(info)/sizeof(DWORD), (const ULONG_PTR*)&info );
768 } __except(EXCEPTION_EXECUTE_HANDLER) {}
769 }
770
771 bool os::distribute_processes(uint length, uint* distribution) {
772 // Not yet implemented.
773 return false;
774 }
775
776 bool os::bind_to_processor(uint processor_id) {
777 // Not yet implemented.
778 return false;
779 }
780
781 void os::win32::initialize_performance_counter() {
782 LARGE_INTEGER count;
783 QueryPerformanceFrequency(&count);
784 performance_frequency = as_long(count);
785 QueryPerformanceCounter(&count);
786 initial_performance_count = as_long(count);
787 }
788
789
790 double os::elapsedTime() {
791 return (double) elapsed_counter() / (double) elapsed_frequency();
792 }
793
794
795 // Windows format:
796 // The FILETIME structure is a 64-bit value representing the number of 100-nanosecond intervals since January 1, 1601.
797 // Java format:
798 // Java standards require the number of milliseconds since 1/1/1970
799
800 // Constant offset - calculated using offset()
801 static jlong _offset = 116444736000000000;
802 // Fake time counter for reproducible results when debugging
803 static jlong fake_time = 0;
804
805 #ifdef ASSERT
806 // Just to be safe, recalculate the offset in debug mode
807 static jlong _calculated_offset = 0;
808 static int _has_calculated_offset = 0;
809
810 jlong offset() {
811 if (_has_calculated_offset) return _calculated_offset;
812 SYSTEMTIME java_origin;
813 java_origin.wYear = 1970;
814 java_origin.wMonth = 1;
815 java_origin.wDayOfWeek = 0; // ignored
816 java_origin.wDay = 1;
817 java_origin.wHour = 0;
818 java_origin.wMinute = 0;
819 java_origin.wSecond = 0;
820 java_origin.wMilliseconds = 0;
821 FILETIME jot;
822 if (!SystemTimeToFileTime(&java_origin, &jot)) {
823 fatal("Error = %d\nWindows error", GetLastError());
824 }
825 _calculated_offset = jlong_from(jot.dwHighDateTime, jot.dwLowDateTime);
826 _has_calculated_offset = 1;
827 assert(_calculated_offset == _offset, "Calculated and constant time offsets must be equal");
828 return _calculated_offset;
829 }
830 #else
831 jlong offset() {
832 return _offset;
833 }
834 #endif
835
836 jlong windows_to_java_time(FILETIME wt) {
837 jlong a = jlong_from(wt.dwHighDateTime, wt.dwLowDateTime);
838 return (a - offset()) / 10000;
839 }
840
841 // Returns time ticks in (10th of micro seconds)
842 jlong windows_to_time_ticks(FILETIME wt) {
843 jlong a = jlong_from(wt.dwHighDateTime, wt.dwLowDateTime);
844 return (a - offset());
845 }
846
847 FILETIME java_to_windows_time(jlong l) {
848 jlong a = (l * 10000) + offset();
849 FILETIME result;
850 result.dwHighDateTime = high(a);
851 result.dwLowDateTime = low(a);
852 return result;
853 }
854
855 bool os::supports_vtime() { return true; }
856 bool os::enable_vtime() { return false; }
857 bool os::vtime_enabled() { return false; }
858
859 double os::elapsedVTime() {
860 FILETIME created;
861 FILETIME exited;
862 FILETIME kernel;
863 FILETIME user;
864 if (GetThreadTimes(GetCurrentThread(), &created, &exited, &kernel, &user) != 0) {
865 // the resolution of windows_to_java_time() should be sufficient (ms)
866 return (double) (windows_to_java_time(kernel) + windows_to_java_time(user)) / MILLIUNITS;
867 } else {
868 return elapsedTime();
869 }
870 }
871
872 jlong os::javaTimeMillis() {
873 if (UseFakeTimers) {
874 return fake_time++;
875 } else {
876 FILETIME wt;
877 GetSystemTimeAsFileTime(&wt);
878 return windows_to_java_time(wt);
879 }
880 }
881
882 void os::javaTimeSystemUTC(jlong &seconds, jlong &nanos) {
883 FILETIME wt;
884 GetSystemTimeAsFileTime(&wt);
885 jlong ticks = windows_to_time_ticks(wt); // 10th of micros
886 jlong secs = jlong(ticks / 10000000); // 10000 * 1000
887 seconds = secs;
888 nanos = jlong(ticks - (secs*10000000)) * 100;
889 }
890
891 jlong os::javaTimeNanos() {
892 LARGE_INTEGER current_count;
893 QueryPerformanceCounter(¤t_count);
894 double current = as_long(current_count);
895 double freq = performance_frequency;
896 jlong time = (jlong)((current/freq) * NANOSECS_PER_SEC);
897 return time;
898 }
899
900 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
901 jlong freq = performance_frequency;
902 if (freq < NANOSECS_PER_SEC) {
903 // the performance counter is 64 bits and we will
904 // be multiplying it -- so no wrap in 64 bits
905 info_ptr->max_value = ALL_64_BITS;
906 } else if (freq > NANOSECS_PER_SEC) {
907 // use the max value the counter can reach to
908 // determine the max value which could be returned
909 julong max_counter = (julong)ALL_64_BITS;
910 info_ptr->max_value = (jlong)(max_counter / (freq / NANOSECS_PER_SEC));
911 } else {
912 // the performance counter is 64 bits and we will
913 // be using it directly -- so no wrap in 64 bits
914 info_ptr->max_value = ALL_64_BITS;
915 }
916
917 // using a counter, so no skipping
918 info_ptr->may_skip_backward = false;
919 info_ptr->may_skip_forward = false;
920
921 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
922 }
923
924 char* os::local_time_string(char *buf, size_t buflen) {
925 SYSTEMTIME st;
926 GetLocalTime(&st);
927 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
928 st.wYear, st.wMonth, st.wDay, st.wHour, st.wMinute, st.wSecond);
929 return buf;
930 }
931
932 bool os::getTimesSecs(double* process_real_time,
933 double* process_user_time,
934 double* process_system_time) {
935 HANDLE h_process = GetCurrentProcess();
936 FILETIME create_time, exit_time, kernel_time, user_time;
937 BOOL result = GetProcessTimes(h_process,
938 &create_time,
939 &exit_time,
940 &kernel_time,
941 &user_time);
942 if (result != 0) {
943 FILETIME wt;
944 GetSystemTimeAsFileTime(&wt);
945 jlong rtc_millis = windows_to_java_time(wt);
946 *process_real_time = ((double) rtc_millis) / ((double) MILLIUNITS);
947 *process_user_time =
948 (double) jlong_from(user_time.dwHighDateTime, user_time.dwLowDateTime) / (10 * MICROUNITS);
949 *process_system_time =
950 (double) jlong_from(kernel_time.dwHighDateTime, kernel_time.dwLowDateTime) / (10 * MICROUNITS);
951 return true;
952 } else {
953 return false;
954 }
955 }
956
957 void os::shutdown() {
958 // allow PerfMemory to attempt cleanup of any persistent resources
959 perfMemory_exit();
960
961 // flush buffered output, finish log files
962 ostream_abort();
963
964 // Check for abort hook
965 abort_hook_t abort_hook = Arguments::abort_hook();
966 if (abort_hook != NULL) {
967 abort_hook();
968 }
969 }
970
971
972 static BOOL (WINAPI *_MiniDumpWriteDump)(HANDLE, DWORD, HANDLE, MINIDUMP_TYPE,
973 PMINIDUMP_EXCEPTION_INFORMATION,
974 PMINIDUMP_USER_STREAM_INFORMATION,
975 PMINIDUMP_CALLBACK_INFORMATION);
976
977 static HANDLE dumpFile = NULL;
978
979 // Check if dump file can be created.
980 void os::check_dump_limit(char* buffer, size_t buffsz) {
981 bool status = true;
982 if (!FLAG_IS_DEFAULT(CreateCoredumpOnCrash) && !CreateCoredumpOnCrash) {
983 jio_snprintf(buffer, buffsz, "CreateCoredumpOnCrash is disabled from command line");
984 status = false;
985 }
986
987 #ifndef ASSERT
988 if (!os::win32::is_windows_server() && FLAG_IS_DEFAULT(CreateCoredumpOnCrash)) {
989 jio_snprintf(buffer, buffsz, "Minidumps are not enabled by default on client versions of Windows");
990 status = false;
991 }
992 #endif
993
994 if (status) {
995 const char* cwd = get_current_directory(NULL, 0);
996 int pid = current_process_id();
997 if (cwd != NULL) {
998 jio_snprintf(buffer, buffsz, "%s\\hs_err_pid%u.mdmp", cwd, pid);
999 } else {
1000 jio_snprintf(buffer, buffsz, ".\\hs_err_pid%u.mdmp", pid);
1001 }
1002
1003 if (dumpFile == NULL &&
1004 (dumpFile = CreateFile(buffer, GENERIC_WRITE, 0, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL))
1005 == INVALID_HANDLE_VALUE) {
1006 jio_snprintf(buffer, buffsz, "Failed to create minidump file (0x%x).", GetLastError());
1007 status = false;
1008 }
1009 }
1010 VMError::record_coredump_status(buffer, status);
1011 }
1012
1013 void os::abort(bool dump_core, void* siginfo, const void* context) {
1014 EXCEPTION_POINTERS ep;
1015 MINIDUMP_EXCEPTION_INFORMATION mei;
1016 MINIDUMP_EXCEPTION_INFORMATION* pmei;
1017
1018 HANDLE hProcess = GetCurrentProcess();
1019 DWORD processId = GetCurrentProcessId();
1020 MINIDUMP_TYPE dumpType;
1021
1022 shutdown();
1023 if (!dump_core || dumpFile == NULL) {
1024 if (dumpFile != NULL) {
1025 CloseHandle(dumpFile);
1026 }
1027 win32::exit_process_or_thread(win32::EPT_PROCESS, 1);
1028 }
1029
1030 dumpType = (MINIDUMP_TYPE)(MiniDumpWithFullMemory | MiniDumpWithHandleData |
1031 MiniDumpWithFullMemoryInfo | MiniDumpWithThreadInfo | MiniDumpWithUnloadedModules);
1032
1033 if (siginfo != NULL && context != NULL) {
1034 ep.ContextRecord = (PCONTEXT) context;
1035 ep.ExceptionRecord = (PEXCEPTION_RECORD) siginfo;
1036
1037 mei.ThreadId = GetCurrentThreadId();
1038 mei.ExceptionPointers = &ep;
1039 pmei = &mei;
1040 } else {
1041 pmei = NULL;
1042 }
1043
1044 // Older versions of dbghelp.dll (the one shipped with Win2003 for example) may not support all
1045 // the dump types we really want. If first call fails, lets fall back to just use MiniDumpWithFullMemory then.
1046 if (!WindowsDbgHelp::miniDumpWriteDump(hProcess, processId, dumpFile, dumpType, pmei, NULL, NULL) &&
1047 !WindowsDbgHelp::miniDumpWriteDump(hProcess, processId, dumpFile, (MINIDUMP_TYPE)MiniDumpWithFullMemory, pmei, NULL, NULL)) {
1048 jio_fprintf(stderr, "Call to MiniDumpWriteDump() failed (Error 0x%x)\n", GetLastError());
1049 }
1050 CloseHandle(dumpFile);
1051 win32::exit_process_or_thread(win32::EPT_PROCESS, 1);
1052 }
1053
1054 // Die immediately, no exit hook, no abort hook, no cleanup.
1055 void os::die() {
1056 win32::exit_process_or_thread(win32::EPT_PROCESS_DIE, -1);
1057 }
1058
1059 // Directory routines copied from src/win32/native/java/io/dirent_md.c
1060 // * dirent_md.c 1.15 00/02/02
1061 //
1062 // The declarations for DIR and struct dirent are in jvm_win32.h.
1063
1064 // Caller must have already run dirname through JVM_NativePath, which removes
1065 // duplicate slashes and converts all instances of '/' into '\\'.
1066
1067 DIR * os::opendir(const char *dirname) {
1068 assert(dirname != NULL, "just checking"); // hotspot change
1069 DIR *dirp = (DIR *)malloc(sizeof(DIR), mtInternal);
1070 DWORD fattr; // hotspot change
1071 char alt_dirname[4] = { 0, 0, 0, 0 };
1072
1073 if (dirp == 0) {
1074 errno = ENOMEM;
1075 return 0;
1076 }
1077
1078 // Win32 accepts "\" in its POSIX stat(), but refuses to treat it
1079 // as a directory in FindFirstFile(). We detect this case here and
1080 // prepend the current drive name.
1081 //
1082 if (dirname[1] == '\0' && dirname[0] == '\\') {
1083 alt_dirname[0] = _getdrive() + 'A' - 1;
1084 alt_dirname[1] = ':';
1085 alt_dirname[2] = '\\';
1086 alt_dirname[3] = '\0';
1087 dirname = alt_dirname;
1088 }
1089
1090 dirp->path = (char *)malloc(strlen(dirname) + 5, mtInternal);
1091 if (dirp->path == 0) {
1092 free(dirp);
1093 errno = ENOMEM;
1094 return 0;
1095 }
1096 strcpy(dirp->path, dirname);
1097
1098 fattr = GetFileAttributes(dirp->path);
1099 if (fattr == 0xffffffff) {
1100 free(dirp->path);
1101 free(dirp);
1102 errno = ENOENT;
1103 return 0;
1104 } else if ((fattr & FILE_ATTRIBUTE_DIRECTORY) == 0) {
1105 free(dirp->path);
1106 free(dirp);
1107 errno = ENOTDIR;
1108 return 0;
1109 }
1110
1111 // Append "*.*", or possibly "\\*.*", to path
1112 if (dirp->path[1] == ':' &&
1113 (dirp->path[2] == '\0' ||
1114 (dirp->path[2] == '\\' && dirp->path[3] == '\0'))) {
1115 // No '\\' needed for cases like "Z:" or "Z:\"
1116 strcat(dirp->path, "*.*");
1117 } else {
1118 strcat(dirp->path, "\\*.*");
1119 }
1120
1121 dirp->handle = FindFirstFile(dirp->path, &dirp->find_data);
1122 if (dirp->handle == INVALID_HANDLE_VALUE) {
1123 if (GetLastError() != ERROR_FILE_NOT_FOUND) {
1124 free(dirp->path);
1125 free(dirp);
1126 errno = EACCES;
1127 return 0;
1128 }
1129 }
1130 return dirp;
1131 }
1132
1133 // parameter dbuf unused on Windows
1134 struct dirent * os::readdir(DIR *dirp, dirent *dbuf) {
1135 assert(dirp != NULL, "just checking"); // hotspot change
1136 if (dirp->handle == INVALID_HANDLE_VALUE) {
1137 return 0;
1138 }
1139
1140 strcpy(dirp->dirent.d_name, dirp->find_data.cFileName);
1141
1142 if (!FindNextFile(dirp->handle, &dirp->find_data)) {
1143 if (GetLastError() == ERROR_INVALID_HANDLE) {
1144 errno = EBADF;
1145 return 0;
1146 }
1147 FindClose(dirp->handle);
1148 dirp->handle = INVALID_HANDLE_VALUE;
1149 }
1150
1151 return &dirp->dirent;
1152 }
1153
1154 int os::closedir(DIR *dirp) {
1155 assert(dirp != NULL, "just checking"); // hotspot change
1156 if (dirp->handle != INVALID_HANDLE_VALUE) {
1157 if (!FindClose(dirp->handle)) {
1158 errno = EBADF;
1159 return -1;
1160 }
1161 dirp->handle = INVALID_HANDLE_VALUE;
1162 }
1163 free(dirp->path);
1164 free(dirp);
1165 return 0;
1166 }
1167
1168 // This must be hard coded because it's the system's temporary
1169 // directory not the java application's temp directory, ala java.io.tmpdir.
1170 const char* os::get_temp_directory() {
1171 static char path_buf[MAX_PATH];
1172 if (GetTempPath(MAX_PATH, path_buf) > 0) {
1173 return path_buf;
1174 } else {
1175 path_buf[0] = '\0';
1176 return path_buf;
1177 }
1178 }
1179
1180 // Needs to be in os specific directory because windows requires another
1181 // header file <direct.h>
1182 const char* os::get_current_directory(char *buf, size_t buflen) {
1183 int n = static_cast<int>(buflen);
1184 if (buflen > INT_MAX) n = INT_MAX;
1185 return _getcwd(buf, n);
1186 }
1187
1188 //-----------------------------------------------------------
1189 // Helper functions for fatal error handler
1190 #ifdef _WIN64
1191 // Helper routine which returns true if address in
1192 // within the NTDLL address space.
1193 //
1194 static bool _addr_in_ntdll(address addr) {
1195 HMODULE hmod;
1196 MODULEINFO minfo;
1197
1198 hmod = GetModuleHandle("NTDLL.DLL");
1199 if (hmod == NULL) return false;
1200 if (!GetModuleInformation(GetCurrentProcess(), hmod,
1201 &minfo, sizeof(MODULEINFO))) {
1202 return false;
1203 }
1204
1205 if ((addr >= minfo.lpBaseOfDll) &&
1206 (addr < (address)((uintptr_t)minfo.lpBaseOfDll + (uintptr_t)minfo.SizeOfImage))) {
1207 return true;
1208 } else {
1209 return false;
1210 }
1211 }
1212 #endif
1213
1214 struct _modinfo {
1215 address addr;
1216 char* full_path; // point to a char buffer
1217 int buflen; // size of the buffer
1218 address base_addr;
1219 };
1220
1221 static int _locate_module_by_addr(const char * mod_fname, address base_addr,
1222 address top_address, void * param) {
1223 struct _modinfo *pmod = (struct _modinfo *)param;
1224 if (!pmod) return -1;
1225
1226 if (base_addr <= pmod->addr &&
1227 top_address > pmod->addr) {
1228 // if a buffer is provided, copy path name to the buffer
1229 if (pmod->full_path) {
1230 jio_snprintf(pmod->full_path, pmod->buflen, "%s", mod_fname);
1231 }
1232 pmod->base_addr = base_addr;
1233 return 1;
1234 }
1235 return 0;
1236 }
1237
1238 bool os::dll_address_to_library_name(address addr, char* buf,
1239 int buflen, int* offset) {
1240 // buf is not optional, but offset is optional
1241 assert(buf != NULL, "sanity check");
1242
1243 // NOTE: the reason we don't use SymGetModuleInfo() is it doesn't always
1244 // return the full path to the DLL file, sometimes it returns path
1245 // to the corresponding PDB file (debug info); sometimes it only
1246 // returns partial path, which makes life painful.
1247
1248 struct _modinfo mi;
1249 mi.addr = addr;
1250 mi.full_path = buf;
1251 mi.buflen = buflen;
1252 if (get_loaded_modules_info(_locate_module_by_addr, (void *)&mi)) {
1253 // buf already contains path name
1254 if (offset) *offset = addr - mi.base_addr;
1255 return true;
1256 }
1257
1258 buf[0] = '\0';
1259 if (offset) *offset = -1;
1260 return false;
1261 }
1262
1263 bool os::dll_address_to_function_name(address addr, char *buf,
1264 int buflen, int *offset,
1265 bool demangle) {
1266 // buf is not optional, but offset is optional
1267 assert(buf != NULL, "sanity check");
1268
1269 if (Decoder::decode(addr, buf, buflen, offset, demangle)) {
1270 return true;
1271 }
1272 if (offset != NULL) *offset = -1;
1273 buf[0] = '\0';
1274 return false;
1275 }
1276
1277 // save the start and end address of jvm.dll into param[0] and param[1]
1278 static int _locate_jvm_dll(const char* mod_fname, address base_addr,
1279 address top_address, void * param) {
1280 if (!param) return -1;
1281
1282 if (base_addr <= (address)_locate_jvm_dll &&
1283 top_address > (address)_locate_jvm_dll) {
1284 ((address*)param)[0] = base_addr;
1285 ((address*)param)[1] = top_address;
1286 return 1;
1287 }
1288 return 0;
1289 }
1290
1291 address vm_lib_location[2]; // start and end address of jvm.dll
1292
1293 // check if addr is inside jvm.dll
1294 bool os::address_is_in_vm(address addr) {
1295 if (!vm_lib_location[0] || !vm_lib_location[1]) {
1296 if (!get_loaded_modules_info(_locate_jvm_dll, (void *)vm_lib_location)) {
1297 assert(false, "Can't find jvm module.");
1298 return false;
1299 }
1300 }
1301
1302 return (vm_lib_location[0] <= addr) && (addr < vm_lib_location[1]);
1303 }
1304
1305 // print module info; param is outputStream*
1306 static int _print_module(const char* fname, address base_address,
1307 address top_address, void* param) {
1308 if (!param) return -1;
1309
1310 outputStream* st = (outputStream*)param;
1311
1312 st->print(PTR_FORMAT " - " PTR_FORMAT " \t%s\n", base_address, top_address, fname);
1313 return 0;
1314 }
1315
1316 // Loads .dll/.so and
1317 // in case of error it checks if .dll/.so was built for the
1318 // same architecture as Hotspot is running on
1319 void * os::dll_load(const char *name, char *ebuf, int ebuflen) {
1320 void * result = LoadLibrary(name);
1321 if (result != NULL) {
1322 return result;
1323 }
1324
1325 DWORD errcode = GetLastError();
1326 if (errcode == ERROR_MOD_NOT_FOUND) {
1327 strncpy(ebuf, "Can't find dependent libraries", ebuflen - 1);
1328 ebuf[ebuflen - 1] = '\0';
1329 return NULL;
1330 }
1331
1332 // Parsing dll below
1333 // If we can read dll-info and find that dll was built
1334 // for an architecture other than Hotspot is running in
1335 // - then print to buffer "DLL was built for a different architecture"
1336 // else call os::lasterror to obtain system error message
1337
1338 // Read system error message into ebuf
1339 // It may or may not be overwritten below (in the for loop and just above)
1340 lasterror(ebuf, (size_t) ebuflen);
1341 ebuf[ebuflen - 1] = '\0';
1342 int fd = ::open(name, O_RDONLY | O_BINARY, 0);
1343 if (fd < 0) {
1344 return NULL;
1345 }
1346
1347 uint32_t signature_offset;
1348 uint16_t lib_arch = 0;
1349 bool failed_to_get_lib_arch =
1350 ( // Go to position 3c in the dll
1351 (os::seek_to_file_offset(fd, IMAGE_FILE_PTR_TO_SIGNATURE) < 0)
1352 ||
1353 // Read location of signature
1354 (sizeof(signature_offset) !=
1355 (os::read(fd, (void*)&signature_offset, sizeof(signature_offset))))
1356 ||
1357 // Go to COFF File Header in dll
1358 // that is located after "signature" (4 bytes long)
1359 (os::seek_to_file_offset(fd,
1360 signature_offset + IMAGE_FILE_SIGNATURE_LENGTH) < 0)
1361 ||
1362 // Read field that contains code of architecture
1363 // that dll was built for
1364 (sizeof(lib_arch) != (os::read(fd, (void*)&lib_arch, sizeof(lib_arch))))
1365 );
1366
1367 ::close(fd);
1368 if (failed_to_get_lib_arch) {
1369 // file i/o error - report os::lasterror(...) msg
1370 return NULL;
1371 }
1372
1373 typedef struct {
1374 uint16_t arch_code;
1375 char* arch_name;
1376 } arch_t;
1377
1378 static const arch_t arch_array[] = {
1379 {IMAGE_FILE_MACHINE_I386, (char*)"IA 32"},
1380 {IMAGE_FILE_MACHINE_AMD64, (char*)"AMD 64"}
1381 };
1382 #if (defined _M_AMD64)
1383 static const uint16_t running_arch = IMAGE_FILE_MACHINE_AMD64;
1384 #elif (defined _M_IX86)
1385 static const uint16_t running_arch = IMAGE_FILE_MACHINE_I386;
1386 #else
1387 #error Method os::dll_load requires that one of following \
1388 is defined :_M_AMD64 or _M_IX86
1389 #endif
1390
1391
1392 // Obtain a string for printf operation
1393 // lib_arch_str shall contain string what platform this .dll was built for
1394 // running_arch_str shall string contain what platform Hotspot was built for
1395 char *running_arch_str = NULL, *lib_arch_str = NULL;
1396 for (unsigned int i = 0; i < ARRAY_SIZE(arch_array); i++) {
1397 if (lib_arch == arch_array[i].arch_code) {
1398 lib_arch_str = arch_array[i].arch_name;
1399 }
1400 if (running_arch == arch_array[i].arch_code) {
1401 running_arch_str = arch_array[i].arch_name;
1402 }
1403 }
1404
1405 assert(running_arch_str,
1406 "Didn't find running architecture code in arch_array");
1407
1408 // If the architecture is right
1409 // but some other error took place - report os::lasterror(...) msg
1410 if (lib_arch == running_arch) {
1411 return NULL;
1412 }
1413
1414 if (lib_arch_str != NULL) {
1415 ::_snprintf(ebuf, ebuflen - 1,
1416 "Can't load %s-bit .dll on a %s-bit platform",
1417 lib_arch_str, running_arch_str);
1418 } else {
1419 // don't know what architecture this dll was build for
1420 ::_snprintf(ebuf, ebuflen - 1,
1421 "Can't load this .dll (machine code=0x%x) on a %s-bit platform",
1422 lib_arch, running_arch_str);
1423 }
1424
1425 return NULL;
1426 }
1427
1428 void os::print_dll_info(outputStream *st) {
1429 st->print_cr("Dynamic libraries:");
1430 get_loaded_modules_info(_print_module, (void *)st);
1431 }
1432
1433 int os::get_loaded_modules_info(os::LoadedModulesCallbackFunc callback, void *param) {
1434 HANDLE hProcess;
1435
1436 # define MAX_NUM_MODULES 128
1437 HMODULE modules[MAX_NUM_MODULES];
1438 static char filename[MAX_PATH];
1439 int result = 0;
1440
1441 int pid = os::current_process_id();
1442 hProcess = OpenProcess(PROCESS_QUERY_INFORMATION | PROCESS_VM_READ,
1443 FALSE, pid);
1444 if (hProcess == NULL) return 0;
1445
1446 DWORD size_needed;
1447 if (!EnumProcessModules(hProcess, modules, sizeof(modules), &size_needed)) {
1448 CloseHandle(hProcess);
1449 return 0;
1450 }
1451
1452 // number of modules that are currently loaded
1453 int num_modules = size_needed / sizeof(HMODULE);
1454
1455 for (int i = 0; i < MIN2(num_modules, MAX_NUM_MODULES); i++) {
1456 // Get Full pathname:
1457 if (!GetModuleFileNameEx(hProcess, modules[i], filename, sizeof(filename))) {
1458 filename[0] = '\0';
1459 }
1460
1461 MODULEINFO modinfo;
1462 if (!GetModuleInformation(hProcess, modules[i], &modinfo, sizeof(modinfo))) {
1463 modinfo.lpBaseOfDll = NULL;
1464 modinfo.SizeOfImage = 0;
1465 }
1466
1467 // Invoke callback function
1468 result = callback(filename, (address)modinfo.lpBaseOfDll,
1469 (address)((u8)modinfo.lpBaseOfDll + (u8)modinfo.SizeOfImage), param);
1470 if (result) break;
1471 }
1472
1473 CloseHandle(hProcess);
1474 return result;
1475 }
1476
1477 bool os::get_host_name(char* buf, size_t buflen) {
1478 DWORD size = (DWORD)buflen;
1479 return (GetComputerNameEx(ComputerNameDnsHostname, buf, &size) == TRUE);
1480 }
1481
1482 void os::get_summary_os_info(char* buf, size_t buflen) {
1483 stringStream sst(buf, buflen);
1484 os::win32::print_windows_version(&sst);
1485 // chop off newline character
1486 char* nl = strchr(buf, '\n');
1487 if (nl != NULL) *nl = '\0';
1488 }
1489
1490 int os::log_vsnprintf(char* buf, size_t len, const char* fmt, va_list args) {
1491 int ret = vsnprintf(buf, len, fmt, args);
1492 // Get the correct buffer size if buf is too small
1493 if (ret < 0) {
1494 return _vscprintf(fmt, args);
1495 }
1496 return ret;
1497 }
1498
1499 static inline time_t get_mtime(const char* filename) {
1500 struct stat st;
1501 int ret = os::stat(filename, &st);
1502 assert(ret == 0, "failed to stat() file '%s': %s", filename, strerror(errno));
1503 return st.st_mtime;
1504 }
1505
1506 int os::compare_file_modified_times(const char* file1, const char* file2) {
1507 time_t t1 = get_mtime(file1);
1508 time_t t2 = get_mtime(file2);
1509 return t1 - t2;
1510 }
1511
1512 void os::print_os_info_brief(outputStream* st) {
1513 os::print_os_info(st);
1514 }
1515
1516 void os::print_os_info(outputStream* st) {
1517 #ifdef ASSERT
1518 char buffer[1024];
1519 st->print("HostName: ");
1520 if (get_host_name(buffer, sizeof(buffer))) {
1521 st->print("%s ", buffer);
1522 } else {
1523 st->print("N/A ");
1524 }
1525 #endif
1526 st->print("OS:");
1527 os::win32::print_windows_version(st);
1528 }
1529
1530 void os::win32::print_windows_version(outputStream* st) {
1531 OSVERSIONINFOEX osvi;
1532 VS_FIXEDFILEINFO *file_info;
1533 TCHAR kernel32_path[MAX_PATH];
1534 UINT len, ret;
1535
1536 // Use the GetVersionEx information to see if we're on a server or
1537 // workstation edition of Windows. Starting with Windows 8.1 we can't
1538 // trust the OS version information returned by this API.
1539 ZeroMemory(&osvi, sizeof(OSVERSIONINFOEX));
1540 osvi.dwOSVersionInfoSize = sizeof(OSVERSIONINFOEX);
1541 if (!GetVersionEx((OSVERSIONINFO *)&osvi)) {
1542 st->print_cr("Call to GetVersionEx failed");
1543 return;
1544 }
1545 bool is_workstation = (osvi.wProductType == VER_NT_WORKSTATION);
1546
1547 // Get the full path to \Windows\System32\kernel32.dll and use that for
1548 // determining what version of Windows we're running on.
1549 len = MAX_PATH - (UINT)strlen("\\kernel32.dll") - 1;
1550 ret = GetSystemDirectory(kernel32_path, len);
1551 if (ret == 0 || ret > len) {
1552 st->print_cr("Call to GetSystemDirectory failed");
1553 return;
1554 }
1555 strncat(kernel32_path, "\\kernel32.dll", MAX_PATH - ret);
1556
1557 DWORD version_size = GetFileVersionInfoSize(kernel32_path, NULL);
1558 if (version_size == 0) {
1559 st->print_cr("Call to GetFileVersionInfoSize failed");
1560 return;
1561 }
1562
1563 LPTSTR version_info = (LPTSTR)os::malloc(version_size, mtInternal);
1564 if (version_info == NULL) {
1565 st->print_cr("Failed to allocate version_info");
1566 return;
1567 }
1568
1569 if (!GetFileVersionInfo(kernel32_path, NULL, version_size, version_info)) {
1570 os::free(version_info);
1571 st->print_cr("Call to GetFileVersionInfo failed");
1572 return;
1573 }
1574
1575 if (!VerQueryValue(version_info, TEXT("\\"), (LPVOID*)&file_info, &len)) {
1576 os::free(version_info);
1577 st->print_cr("Call to VerQueryValue failed");
1578 return;
1579 }
1580
1581 int major_version = HIWORD(file_info->dwProductVersionMS);
1582 int minor_version = LOWORD(file_info->dwProductVersionMS);
1583 int build_number = HIWORD(file_info->dwProductVersionLS);
1584 int build_minor = LOWORD(file_info->dwProductVersionLS);
1585 int os_vers = major_version * 1000 + minor_version;
1586 os::free(version_info);
1587
1588 st->print(" Windows ");
1589 switch (os_vers) {
1590
1591 case 6000:
1592 if (is_workstation) {
1593 st->print("Vista");
1594 } else {
1595 st->print("Server 2008");
1596 }
1597 break;
1598
1599 case 6001:
1600 if (is_workstation) {
1601 st->print("7");
1602 } else {
1603 st->print("Server 2008 R2");
1604 }
1605 break;
1606
1607 case 6002:
1608 if (is_workstation) {
1609 st->print("8");
1610 } else {
1611 st->print("Server 2012");
1612 }
1613 break;
1614
1615 case 6003:
1616 if (is_workstation) {
1617 st->print("8.1");
1618 } else {
1619 st->print("Server 2012 R2");
1620 }
1621 break;
1622
1623 case 10000:
1624 if (is_workstation) {
1625 st->print("10");
1626 } else {
1627 st->print("Server 2016");
1628 }
1629 break;
1630
1631 default:
1632 // Unrecognized windows, print out its major and minor versions
1633 st->print("%d.%d", major_version, minor_version);
1634 break;
1635 }
1636
1637 // Retrieve SYSTEM_INFO from GetNativeSystemInfo call so that we could
1638 // find out whether we are running on 64 bit processor or not
1639 SYSTEM_INFO si;
1640 ZeroMemory(&si, sizeof(SYSTEM_INFO));
1641 GetNativeSystemInfo(&si);
1642 if (si.wProcessorArchitecture == PROCESSOR_ARCHITECTURE_AMD64) {
1643 st->print(" , 64 bit");
1644 }
1645
1646 st->print(" Build %d", build_number);
1647 st->print(" (%d.%d.%d.%d)", major_version, minor_version, build_number, build_minor);
1648 st->cr();
1649 }
1650
1651 void os::pd_print_cpu_info(outputStream* st, char* buf, size_t buflen) {
1652 // Nothing to do for now.
1653 }
1654
1655 void os::get_summary_cpu_info(char* buf, size_t buflen) {
1656 HKEY key;
1657 DWORD status = RegOpenKey(HKEY_LOCAL_MACHINE,
1658 "HARDWARE\\DESCRIPTION\\System\\CentralProcessor\\0", &key);
1659 if (status == ERROR_SUCCESS) {
1660 DWORD size = (DWORD)buflen;
1661 status = RegQueryValueEx(key, "ProcessorNameString", NULL, NULL, (byte*)buf, &size);
1662 if (status != ERROR_SUCCESS) {
1663 strncpy(buf, "## __CPU__", buflen);
1664 }
1665 RegCloseKey(key);
1666 } else {
1667 // Put generic cpu info to return
1668 strncpy(buf, "## __CPU__", buflen);
1669 }
1670 }
1671
1672 void os::print_memory_info(outputStream* st) {
1673 st->print("Memory:");
1674 st->print(" %dk page", os::vm_page_size()>>10);
1675
1676 // Use GlobalMemoryStatusEx() because GlobalMemoryStatus() may return incorrect
1677 // value if total memory is larger than 4GB
1678 MEMORYSTATUSEX ms;
1679 ms.dwLength = sizeof(ms);
1680 GlobalMemoryStatusEx(&ms);
1681
1682 st->print(", physical %uk", os::physical_memory() >> 10);
1683 st->print("(%uk free)", os::available_memory() >> 10);
1684
1685 st->print(", swap %uk", ms.ullTotalPageFile >> 10);
1686 st->print("(%uk free)", ms.ullAvailPageFile >> 10);
1687 st->cr();
1688 }
1689
1690 void os::print_siginfo(outputStream *st, const void* siginfo) {
1691 const EXCEPTION_RECORD* const er = (EXCEPTION_RECORD*)siginfo;
1692 st->print("siginfo:");
1693
1694 char tmp[64];
1695 if (os::exception_name(er->ExceptionCode, tmp, sizeof(tmp)) == NULL) {
1696 strcpy(tmp, "EXCEPTION_??");
1697 }
1698 st->print(" %s (0x%x)", tmp, er->ExceptionCode);
1699
1700 if ((er->ExceptionCode == EXCEPTION_ACCESS_VIOLATION ||
1701 er->ExceptionCode == EXCEPTION_IN_PAGE_ERROR) &&
1702 er->NumberParameters >= 2) {
1703 switch (er->ExceptionInformation[0]) {
1704 case 0: st->print(", reading address"); break;
1705 case 1: st->print(", writing address"); break;
1706 case 8: st->print(", data execution prevention violation at address"); break;
1707 default: st->print(", ExceptionInformation=" INTPTR_FORMAT,
1708 er->ExceptionInformation[0]);
1709 }
1710 st->print(" " INTPTR_FORMAT, er->ExceptionInformation[1]);
1711 } else {
1712 int num = er->NumberParameters;
1713 if (num > 0) {
1714 st->print(", ExceptionInformation=");
1715 for (int i = 0; i < num; i++) {
1716 st->print(INTPTR_FORMAT " ", er->ExceptionInformation[i]);
1717 }
1718 }
1719 }
1720 st->cr();
1721 }
1722
1723 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1724 // do nothing
1725 }
1726
1727 static char saved_jvm_path[MAX_PATH] = {0};
1728
1729 // Find the full path to the current module, jvm.dll
1730 void os::jvm_path(char *buf, jint buflen) {
1731 // Error checking.
1732 if (buflen < MAX_PATH) {
1733 assert(false, "must use a large-enough buffer");
1734 buf[0] = '\0';
1735 return;
1736 }
1737 // Lazy resolve the path to current module.
1738 if (saved_jvm_path[0] != 0) {
1739 strcpy(buf, saved_jvm_path);
1740 return;
1741 }
1742
1743 buf[0] = '\0';
1744 if (Arguments::sun_java_launcher_is_altjvm()) {
1745 // Support for the java launcher's '-XXaltjvm=<path>' option. Check
1746 // for a JAVA_HOME environment variable and fix up the path so it
1747 // looks like jvm.dll is installed there (append a fake suffix
1748 // hotspot/jvm.dll).
1749 char* java_home_var = ::getenv("JAVA_HOME");
1750 if (java_home_var != NULL && java_home_var[0] != 0 &&
1751 strlen(java_home_var) < (size_t)buflen) {
1752 strncpy(buf, java_home_var, buflen);
1753
1754 // determine if this is a legacy image or modules image
1755 // modules image doesn't have "jre" subdirectory
1756 size_t len = strlen(buf);
1757 char* jrebin_p = buf + len;
1758 jio_snprintf(jrebin_p, buflen-len, "\\jre\\bin\\");
1759 if (0 != _access(buf, 0)) {
1760 jio_snprintf(jrebin_p, buflen-len, "\\bin\\");
1761 }
1762 len = strlen(buf);
1763 jio_snprintf(buf + len, buflen-len, "hotspot\\jvm.dll");
1764 }
1765 }
1766
1767 if (buf[0] == '\0') {
1768 GetModuleFileName(vm_lib_handle, buf, buflen);
1769 }
1770 strncpy(saved_jvm_path, buf, MAX_PATH);
1771 saved_jvm_path[MAX_PATH - 1] = '\0';
1772 }
1773
1774
1775 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1776 #ifndef _WIN64
1777 st->print("_");
1778 #endif
1779 }
1780
1781
1782 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1783 #ifndef _WIN64
1784 st->print("@%d", args_size * sizeof(int));
1785 #endif
1786 }
1787
1788 // This method is a copy of JDK's sysGetLastErrorString
1789 // from src/windows/hpi/src/system_md.c
1790
1791 size_t os::lasterror(char* buf, size_t len) {
1792 DWORD errval;
1793
1794 if ((errval = GetLastError()) != 0) {
1795 // DOS error
1796 size_t n = (size_t)FormatMessage(
1797 FORMAT_MESSAGE_FROM_SYSTEM|FORMAT_MESSAGE_IGNORE_INSERTS,
1798 NULL,
1799 errval,
1800 0,
1801 buf,
1802 (DWORD)len,
1803 NULL);
1804 if (n > 3) {
1805 // Drop final '.', CR, LF
1806 if (buf[n - 1] == '\n') n--;
1807 if (buf[n - 1] == '\r') n--;
1808 if (buf[n - 1] == '.') n--;
1809 buf[n] = '\0';
1810 }
1811 return n;
1812 }
1813
1814 if (errno != 0) {
1815 // C runtime error that has no corresponding DOS error code
1816 const char* s = os::strerror(errno);
1817 size_t n = strlen(s);
1818 if (n >= len) n = len - 1;
1819 strncpy(buf, s, n);
1820 buf[n] = '\0';
1821 return n;
1822 }
1823
1824 return 0;
1825 }
1826
1827 int os::get_last_error() {
1828 DWORD error = GetLastError();
1829 if (error == 0) {
1830 error = errno;
1831 }
1832 return (int)error;
1833 }
1834
1835 WindowsSemaphore::WindowsSemaphore(uint value) {
1836 _semaphore = ::CreateSemaphore(NULL, value, LONG_MAX, NULL);
1837
1838 guarantee(_semaphore != NULL, "CreateSemaphore failed with error code: %lu", GetLastError());
1839 }
1840
1841 WindowsSemaphore::~WindowsSemaphore() {
1842 ::CloseHandle(_semaphore);
1843 }
1844
1845 void WindowsSemaphore::signal(uint count) {
1846 if (count > 0) {
1847 BOOL ret = ::ReleaseSemaphore(_semaphore, count, NULL);
1848
1849 assert(ret != 0, "ReleaseSemaphore failed with error code: %lu", GetLastError());
1850 }
1851 }
1852
1853 void WindowsSemaphore::wait() {
1854 DWORD ret = ::WaitForSingleObject(_semaphore, INFINITE);
1855 assert(ret != WAIT_FAILED, "WaitForSingleObject failed with error code: %lu", GetLastError());
1856 assert(ret == WAIT_OBJECT_0, "WaitForSingleObject failed with return value: %lu", ret);
1857 }
1858
1859 bool WindowsSemaphore::trywait() {
1860 DWORD ret = ::WaitForSingleObject(_semaphore, 0);
1861 assert(ret != WAIT_FAILED, "WaitForSingleObject failed with error code: %lu", GetLastError());
1862 return ret == WAIT_OBJECT_0;
1863 }
1864
1865 // sun.misc.Signal
1866 // NOTE that this is a workaround for an apparent kernel bug where if
1867 // a signal handler for SIGBREAK is installed then that signal handler
1868 // takes priority over the console control handler for CTRL_CLOSE_EVENT.
1869 // See bug 4416763.
1870 static void (*sigbreakHandler)(int) = NULL;
1871
1872 static void UserHandler(int sig, void *siginfo, void *context) {
1873 os::signal_notify(sig);
1874 // We need to reinstate the signal handler each time...
1875 os::signal(sig, (void*)UserHandler);
1876 }
1877
1878 void* os::user_handler() {
1879 return (void*) UserHandler;
1880 }
1881
1882 void* os::signal(int signal_number, void* handler) {
1883 if ((signal_number == SIGBREAK) && (!ReduceSignalUsage)) {
1884 void (*oldHandler)(int) = sigbreakHandler;
1885 sigbreakHandler = (void (*)(int)) handler;
1886 return (void*) oldHandler;
1887 } else {
1888 return (void*)::signal(signal_number, (void (*)(int))handler);
1889 }
1890 }
1891
1892 void os::signal_raise(int signal_number) {
1893 raise(signal_number);
1894 }
1895
1896 // The Win32 C runtime library maps all console control events other than ^C
1897 // into SIGBREAK, which makes it impossible to distinguish ^BREAK from close,
1898 // logoff, and shutdown events. We therefore install our own console handler
1899 // that raises SIGTERM for the latter cases.
1900 //
1901 static BOOL WINAPI consoleHandler(DWORD event) {
1902 switch (event) {
1903 case CTRL_C_EVENT:
1904 if (VMError::is_error_reported()) {
1905 // Ctrl-C is pressed during error reporting, likely because the error
1906 // handler fails to abort. Let VM die immediately.
1907 os::die();
1908 }
1909
1910 os::signal_raise(SIGINT);
1911 return TRUE;
1912 break;
1913 case CTRL_BREAK_EVENT:
1914 if (sigbreakHandler != NULL) {
1915 (*sigbreakHandler)(SIGBREAK);
1916 }
1917 return TRUE;
1918 break;
1919 case CTRL_LOGOFF_EVENT: {
1920 // Don't terminate JVM if it is running in a non-interactive session,
1921 // such as a service process.
1922 USEROBJECTFLAGS flags;
1923 HANDLE handle = GetProcessWindowStation();
1924 if (handle != NULL &&
1925 GetUserObjectInformation(handle, UOI_FLAGS, &flags,
1926 sizeof(USEROBJECTFLAGS), NULL)) {
1927 // If it is a non-interactive session, let next handler to deal
1928 // with it.
1929 if ((flags.dwFlags & WSF_VISIBLE) == 0) {
1930 return FALSE;
1931 }
1932 }
1933 }
1934 case CTRL_CLOSE_EVENT:
1935 case CTRL_SHUTDOWN_EVENT:
1936 os::signal_raise(SIGTERM);
1937 return TRUE;
1938 break;
1939 default:
1940 break;
1941 }
1942 return FALSE;
1943 }
1944
1945 // The following code is moved from os.cpp for making this
1946 // code platform specific, which it is by its very nature.
1947
1948 // Return maximum OS signal used + 1 for internal use only
1949 // Used as exit signal for signal_thread
1950 int os::sigexitnum_pd() {
1951 return NSIG;
1952 }
1953
1954 // a counter for each possible signal value, including signal_thread exit signal
1955 static volatile jint pending_signals[NSIG+1] = { 0 };
1956 static HANDLE sig_sem = NULL;
1957
1958 void os::signal_init_pd() {
1959 // Initialize signal structures
1960 memset((void*)pending_signals, 0, sizeof(pending_signals));
1961
1962 sig_sem = ::CreateSemaphore(NULL, 0, NSIG+1, NULL);
1963
1964 // Programs embedding the VM do not want it to attempt to receive
1965 // events like CTRL_LOGOFF_EVENT, which are used to implement the
1966 // shutdown hooks mechanism introduced in 1.3. For example, when
1967 // the VM is run as part of a Windows NT service (i.e., a servlet
1968 // engine in a web server), the correct behavior is for any console
1969 // control handler to return FALSE, not TRUE, because the OS's
1970 // "final" handler for such events allows the process to continue if
1971 // it is a service (while terminating it if it is not a service).
1972 // To make this behavior uniform and the mechanism simpler, we
1973 // completely disable the VM's usage of these console events if -Xrs
1974 // (=ReduceSignalUsage) is specified. This means, for example, that
1975 // the CTRL-BREAK thread dump mechanism is also disabled in this
1976 // case. See bugs 4323062, 4345157, and related bugs.
1977
1978 if (!ReduceSignalUsage) {
1979 // Add a CTRL-C handler
1980 SetConsoleCtrlHandler(consoleHandler, TRUE);
1981 }
1982 }
1983
1984 void os::signal_notify(int signal_number) {
1985 BOOL ret;
1986 if (sig_sem != NULL) {
1987 Atomic::inc(&pending_signals[signal_number]);
1988 ret = ::ReleaseSemaphore(sig_sem, 1, NULL);
1989 assert(ret != 0, "ReleaseSemaphore() failed");
1990 }
1991 }
1992
1993 static int check_pending_signals(bool wait_for_signal) {
1994 DWORD ret;
1995 while (true) {
1996 for (int i = 0; i < NSIG + 1; i++) {
1997 jint n = pending_signals[i];
1998 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
1999 return i;
2000 }
2001 }
2002 if (!wait_for_signal) {
2003 return -1;
2004 }
2005
2006 JavaThread *thread = JavaThread::current();
2007
2008 ThreadBlockInVM tbivm(thread);
2009
2010 bool threadIsSuspended;
2011 do {
2012 thread->set_suspend_equivalent();
2013 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
2014 ret = ::WaitForSingleObject(sig_sem, INFINITE);
2015 assert(ret == WAIT_OBJECT_0, "WaitForSingleObject() failed");
2016
2017 // were we externally suspended while we were waiting?
2018 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
2019 if (threadIsSuspended) {
2020 // The semaphore has been incremented, but while we were waiting
2021 // another thread suspended us. We don't want to continue running
2022 // while suspended because that would surprise the thread that
2023 // suspended us.
2024 ret = ::ReleaseSemaphore(sig_sem, 1, NULL);
2025 assert(ret != 0, "ReleaseSemaphore() failed");
2026
2027 thread->java_suspend_self();
2028 }
2029 } while (threadIsSuspended);
2030 }
2031 }
2032
2033 int os::signal_lookup() {
2034 return check_pending_signals(false);
2035 }
2036
2037 int os::signal_wait() {
2038 return check_pending_signals(true);
2039 }
2040
2041 // Implicit OS exception handling
2042
2043 LONG Handle_Exception(struct _EXCEPTION_POINTERS* exceptionInfo,
2044 address handler) {
2045 JavaThread* thread = (JavaThread*) Thread::current_or_null();
2046 // Save pc in thread
2047 #ifdef _M_AMD64
2048 // Do not blow up if no thread info available.
2049 if (thread) {
2050 thread->set_saved_exception_pc((address)(DWORD_PTR)exceptionInfo->ContextRecord->Rip);
2051 }
2052 // Set pc to handler
2053 exceptionInfo->ContextRecord->Rip = (DWORD64)handler;
2054 #else
2055 // Do not blow up if no thread info available.
2056 if (thread) {
2057 thread->set_saved_exception_pc((address)(DWORD_PTR)exceptionInfo->ContextRecord->Eip);
2058 }
2059 // Set pc to handler
2060 exceptionInfo->ContextRecord->Eip = (DWORD)(DWORD_PTR)handler;
2061 #endif
2062
2063 // Continue the execution
2064 return EXCEPTION_CONTINUE_EXECUTION;
2065 }
2066
2067
2068 // Used for PostMortemDump
2069 extern "C" void safepoints();
2070 extern "C" void find(int x);
2071 extern "C" void events();
2072
2073 // According to Windows API documentation, an illegal instruction sequence should generate
2074 // the 0xC000001C exception code. However, real world experience shows that occasionnaly
2075 // the execution of an illegal instruction can generate the exception code 0xC000001E. This
2076 // seems to be an undocumented feature of Win NT 4.0 (and probably other Windows systems).
2077
2078 #define EXCEPTION_ILLEGAL_INSTRUCTION_2 0xC000001E
2079
2080 // From "Execution Protection in the Windows Operating System" draft 0.35
2081 // Once a system header becomes available, the "real" define should be
2082 // included or copied here.
2083 #define EXCEPTION_INFO_EXEC_VIOLATION 0x08
2084
2085 // Windows Vista/2008 heap corruption check
2086 #define EXCEPTION_HEAP_CORRUPTION 0xC0000374
2087
2088 // All Visual C++ exceptions thrown from code generated by the Microsoft Visual
2089 // C++ compiler contain this error code. Because this is a compiler-generated
2090 // error, the code is not listed in the Win32 API header files.
2091 // The code is actually a cryptic mnemonic device, with the initial "E"
2092 // standing for "exception" and the final 3 bytes (0x6D7363) representing the
2093 // ASCII values of "msc".
2094
2095 #define EXCEPTION_UNCAUGHT_CXX_EXCEPTION 0xE06D7363
2096
2097 #define def_excpt(val) { #val, (val) }
2098
2099 static const struct { char* name; uint number; } exceptlabels[] = {
2100 def_excpt(EXCEPTION_ACCESS_VIOLATION),
2101 def_excpt(EXCEPTION_DATATYPE_MISALIGNMENT),
2102 def_excpt(EXCEPTION_BREAKPOINT),
2103 def_excpt(EXCEPTION_SINGLE_STEP),
2104 def_excpt(EXCEPTION_ARRAY_BOUNDS_EXCEEDED),
2105 def_excpt(EXCEPTION_FLT_DENORMAL_OPERAND),
2106 def_excpt(EXCEPTION_FLT_DIVIDE_BY_ZERO),
2107 def_excpt(EXCEPTION_FLT_INEXACT_RESULT),
2108 def_excpt(EXCEPTION_FLT_INVALID_OPERATION),
2109 def_excpt(EXCEPTION_FLT_OVERFLOW),
2110 def_excpt(EXCEPTION_FLT_STACK_CHECK),
2111 def_excpt(EXCEPTION_FLT_UNDERFLOW),
2112 def_excpt(EXCEPTION_INT_DIVIDE_BY_ZERO),
2113 def_excpt(EXCEPTION_INT_OVERFLOW),
2114 def_excpt(EXCEPTION_PRIV_INSTRUCTION),
2115 def_excpt(EXCEPTION_IN_PAGE_ERROR),
2116 def_excpt(EXCEPTION_ILLEGAL_INSTRUCTION),
2117 def_excpt(EXCEPTION_ILLEGAL_INSTRUCTION_2),
2118 def_excpt(EXCEPTION_NONCONTINUABLE_EXCEPTION),
2119 def_excpt(EXCEPTION_STACK_OVERFLOW),
2120 def_excpt(EXCEPTION_INVALID_DISPOSITION),
2121 def_excpt(EXCEPTION_GUARD_PAGE),
2122 def_excpt(EXCEPTION_INVALID_HANDLE),
2123 def_excpt(EXCEPTION_UNCAUGHT_CXX_EXCEPTION),
2124 def_excpt(EXCEPTION_HEAP_CORRUPTION)
2125 };
2126
2127 #undef def_excpt
2128
2129 const char* os::exception_name(int exception_code, char *buf, size_t size) {
2130 uint code = static_cast<uint>(exception_code);
2131 for (uint i = 0; i < ARRAY_SIZE(exceptlabels); ++i) {
2132 if (exceptlabels[i].number == code) {
2133 jio_snprintf(buf, size, "%s", exceptlabels[i].name);
2134 return buf;
2135 }
2136 }
2137
2138 return NULL;
2139 }
2140
2141 //-----------------------------------------------------------------------------
2142 LONG Handle_IDiv_Exception(struct _EXCEPTION_POINTERS* exceptionInfo) {
2143 // handle exception caused by idiv; should only happen for -MinInt/-1
2144 // (division by zero is handled explicitly)
2145 #ifdef _M_AMD64
2146 PCONTEXT ctx = exceptionInfo->ContextRecord;
2147 address pc = (address)ctx->Rip;
2148 assert(pc[0] >= Assembler::REX && pc[0] <= Assembler::REX_WRXB && pc[1] == 0xF7 || pc[0] == 0xF7, "not an idiv opcode");
2149 assert(pc[0] >= Assembler::REX && pc[0] <= Assembler::REX_WRXB && (pc[2] & ~0x7) == 0xF8 || (pc[1] & ~0x7) == 0xF8, "cannot handle non-register operands");
2150 if (pc[0] == 0xF7) {
2151 // set correct result values and continue after idiv instruction
2152 ctx->Rip = (DWORD64)pc + 2; // idiv reg, reg is 2 bytes
2153 } else {
2154 ctx->Rip = (DWORD64)pc + 3; // REX idiv reg, reg is 3 bytes
2155 }
2156 // Do not set ctx->Rax as it already contains the correct value (either 32 or 64 bit, depending on the operation)
2157 // this is the case because the exception only happens for -MinValue/-1 and -MinValue is always in rax because of the
2158 // idiv opcode (0xF7).
2159 ctx->Rdx = (DWORD)0; // remainder
2160 // Continue the execution
2161 #else
2162 PCONTEXT ctx = exceptionInfo->ContextRecord;
2163 address pc = (address)ctx->Eip;
2164 assert(pc[0] == 0xF7, "not an idiv opcode");
2165 assert((pc[1] & ~0x7) == 0xF8, "cannot handle non-register operands");
2166 assert(ctx->Eax == min_jint, "unexpected idiv exception");
2167 // set correct result values and continue after idiv instruction
2168 ctx->Eip = (DWORD)pc + 2; // idiv reg, reg is 2 bytes
2169 ctx->Eax = (DWORD)min_jint; // result
2170 ctx->Edx = (DWORD)0; // remainder
2171 // Continue the execution
2172 #endif
2173 return EXCEPTION_CONTINUE_EXECUTION;
2174 }
2175
2176 //-----------------------------------------------------------------------------
2177 LONG WINAPI Handle_FLT_Exception(struct _EXCEPTION_POINTERS* exceptionInfo) {
2178 PCONTEXT ctx = exceptionInfo->ContextRecord;
2179 #ifndef _WIN64
2180 // handle exception caused by native method modifying control word
2181 DWORD exception_code = exceptionInfo->ExceptionRecord->ExceptionCode;
2182
2183 switch (exception_code) {
2184 case EXCEPTION_FLT_DENORMAL_OPERAND:
2185 case EXCEPTION_FLT_DIVIDE_BY_ZERO:
2186 case EXCEPTION_FLT_INEXACT_RESULT:
2187 case EXCEPTION_FLT_INVALID_OPERATION:
2188 case EXCEPTION_FLT_OVERFLOW:
2189 case EXCEPTION_FLT_STACK_CHECK:
2190 case EXCEPTION_FLT_UNDERFLOW:
2191 jint fp_control_word = (* (jint*) StubRoutines::addr_fpu_cntrl_wrd_std());
2192 if (fp_control_word != ctx->FloatSave.ControlWord) {
2193 // Restore FPCW and mask out FLT exceptions
2194 ctx->FloatSave.ControlWord = fp_control_word | 0xffffffc0;
2195 // Mask out pending FLT exceptions
2196 ctx->FloatSave.StatusWord &= 0xffffff00;
2197 return EXCEPTION_CONTINUE_EXECUTION;
2198 }
2199 }
2200
2201 if (prev_uef_handler != NULL) {
2202 // We didn't handle this exception so pass it to the previous
2203 // UnhandledExceptionFilter.
2204 return (prev_uef_handler)(exceptionInfo);
2205 }
2206 #else // !_WIN64
2207 // On Windows, the mxcsr control bits are non-volatile across calls
2208 // See also CR 6192333
2209 //
2210 jint MxCsr = INITIAL_MXCSR;
2211 // we can't use StubRoutines::addr_mxcsr_std()
2212 // because in Win64 mxcsr is not saved there
2213 if (MxCsr != ctx->MxCsr) {
2214 ctx->MxCsr = MxCsr;
2215 return EXCEPTION_CONTINUE_EXECUTION;
2216 }
2217 #endif // !_WIN64
2218
2219 return EXCEPTION_CONTINUE_SEARCH;
2220 }
2221
2222 static inline void report_error(Thread* t, DWORD exception_code,
2223 address addr, void* siginfo, void* context) {
2224 VMError::report_and_die(t, exception_code, addr, siginfo, context);
2225
2226 // If UseOsErrorReporting, this will return here and save the error file
2227 // somewhere where we can find it in the minidump.
2228 }
2229
2230 bool os::win32::get_frame_at_stack_banging_point(JavaThread* thread,
2231 struct _EXCEPTION_POINTERS* exceptionInfo, address pc, frame* fr) {
2232 PEXCEPTION_RECORD exceptionRecord = exceptionInfo->ExceptionRecord;
2233 address addr = (address) exceptionRecord->ExceptionInformation[1];
2234 if (Interpreter::contains(pc)) {
2235 *fr = os::fetch_frame_from_context((void*)exceptionInfo->ContextRecord);
2236 if (!fr->is_first_java_frame()) {
2237 // get_frame_at_stack_banging_point() is only called when we
2238 // have well defined stacks so java_sender() calls do not need
2239 // to assert safe_for_sender() first.
2240 *fr = fr->java_sender();
2241 }
2242 } else {
2243 // more complex code with compiled code
2244 assert(!Interpreter::contains(pc), "Interpreted methods should have been handled above");
2245 CodeBlob* cb = CodeCache::find_blob(pc);
2246 if (cb == NULL || !cb->is_nmethod() || cb->is_frame_complete_at(pc)) {
2247 // Not sure where the pc points to, fallback to default
2248 // stack overflow handling
2249 return false;
2250 } else {
2251 *fr = os::fetch_frame_from_context((void*)exceptionInfo->ContextRecord);
2252 // in compiled code, the stack banging is performed just after the return pc
2253 // has been pushed on the stack
2254 *fr = frame(fr->sp() + 1, fr->fp(), (address)*(fr->sp()));
2255 if (!fr->is_java_frame()) {
2256 // See java_sender() comment above.
2257 *fr = fr->java_sender();
2258 }
2259 }
2260 }
2261 assert(fr->is_java_frame(), "Safety check");
2262 return true;
2263 }
2264
2265 //-----------------------------------------------------------------------------
2266 LONG WINAPI topLevelExceptionFilter(struct _EXCEPTION_POINTERS* exceptionInfo) {
2267 if (InterceptOSException) return EXCEPTION_CONTINUE_SEARCH;
2268 DWORD exception_code = exceptionInfo->ExceptionRecord->ExceptionCode;
2269 #ifdef _M_AMD64
2270 address pc = (address) exceptionInfo->ContextRecord->Rip;
2271 #else
2272 address pc = (address) exceptionInfo->ContextRecord->Eip;
2273 #endif
2274 Thread* t = Thread::current_or_null_safe();
2275
2276 // Handle SafeFetch32 and SafeFetchN exceptions.
2277 if (StubRoutines::is_safefetch_fault(pc)) {
2278 return Handle_Exception(exceptionInfo, StubRoutines::continuation_for_safefetch_fault(pc));
2279 }
2280
2281 #ifndef _WIN64
2282 // Execution protection violation - win32 running on AMD64 only
2283 // Handled first to avoid misdiagnosis as a "normal" access violation;
2284 // This is safe to do because we have a new/unique ExceptionInformation
2285 // code for this condition.
2286 if (exception_code == EXCEPTION_ACCESS_VIOLATION) {
2287 PEXCEPTION_RECORD exceptionRecord = exceptionInfo->ExceptionRecord;
2288 int exception_subcode = (int) exceptionRecord->ExceptionInformation[0];
2289 address addr = (address) exceptionRecord->ExceptionInformation[1];
2290
2291 if (exception_subcode == EXCEPTION_INFO_EXEC_VIOLATION) {
2292 int page_size = os::vm_page_size();
2293
2294 // Make sure the pc and the faulting address are sane.
2295 //
2296 // If an instruction spans a page boundary, and the page containing
2297 // the beginning of the instruction is executable but the following
2298 // page is not, the pc and the faulting address might be slightly
2299 // different - we still want to unguard the 2nd page in this case.
2300 //
2301 // 15 bytes seems to be a (very) safe value for max instruction size.
2302 bool pc_is_near_addr =
2303 (pointer_delta((void*) addr, (void*) pc, sizeof(char)) < 15);
2304 bool instr_spans_page_boundary =
2305 (align_down((intptr_t) pc ^ (intptr_t) addr,
2306 (intptr_t) page_size) > 0);
2307
2308 if (pc == addr || (pc_is_near_addr && instr_spans_page_boundary)) {
2309 static volatile address last_addr =
2310 (address) os::non_memory_address_word();
2311
2312 // In conservative mode, don't unguard unless the address is in the VM
2313 if (UnguardOnExecutionViolation > 0 && addr != last_addr &&
2314 (UnguardOnExecutionViolation > 1 || os::address_is_in_vm(addr))) {
2315
2316 // Set memory to RWX and retry
2317 address page_start = align_down(addr, page_size);
2318 bool res = os::protect_memory((char*) page_start, page_size,
2319 os::MEM_PROT_RWX);
2320
2321 log_debug(os)("Execution protection violation "
2322 "at " INTPTR_FORMAT
2323 ", unguarding " INTPTR_FORMAT ": %s", p2i(addr),
2324 p2i(page_start), (res ? "success" : os::strerror(errno)));
2325
2326 // Set last_addr so if we fault again at the same address, we don't
2327 // end up in an endless loop.
2328 //
2329 // There are two potential complications here. Two threads trapping
2330 // at the same address at the same time could cause one of the
2331 // threads to think it already unguarded, and abort the VM. Likely
2332 // very rare.
2333 //
2334 // The other race involves two threads alternately trapping at
2335 // different addresses and failing to unguard the page, resulting in
2336 // an endless loop. This condition is probably even more unlikely
2337 // than the first.
2338 //
2339 // Although both cases could be avoided by using locks or thread
2340 // local last_addr, these solutions are unnecessary complication:
2341 // this handler is a best-effort safety net, not a complete solution.
2342 // It is disabled by default and should only be used as a workaround
2343 // in case we missed any no-execute-unsafe VM code.
2344
2345 last_addr = addr;
2346
2347 return EXCEPTION_CONTINUE_EXECUTION;
2348 }
2349 }
2350
2351 // Last unguard failed or not unguarding
2352 tty->print_raw_cr("Execution protection violation");
2353 report_error(t, exception_code, addr, exceptionInfo->ExceptionRecord,
2354 exceptionInfo->ContextRecord);
2355 return EXCEPTION_CONTINUE_SEARCH;
2356 }
2357 }
2358 #endif // _WIN64
2359
2360 // Check to see if we caught the safepoint code in the
2361 // process of write protecting the memory serialization page.
2362 // It write enables the page immediately after protecting it
2363 // so just return.
2364 if (exception_code == EXCEPTION_ACCESS_VIOLATION) {
2365 if (t != NULL && t->is_Java_thread()) {
2366 JavaThread* thread = (JavaThread*) t;
2367 PEXCEPTION_RECORD exceptionRecord = exceptionInfo->ExceptionRecord;
2368 address addr = (address) exceptionRecord->ExceptionInformation[1];
2369 if (os::is_memory_serialize_page(thread, addr)) {
2370 // Block current thread until the memory serialize page permission restored.
2371 os::block_on_serialize_page_trap();
2372 return EXCEPTION_CONTINUE_EXECUTION;
2373 }
2374 }
2375 }
2376
2377 if ((exception_code == EXCEPTION_ACCESS_VIOLATION) &&
2378 VM_Version::is_cpuinfo_segv_addr(pc)) {
2379 // Verify that OS save/restore AVX registers.
2380 return Handle_Exception(exceptionInfo, VM_Version::cpuinfo_cont_addr());
2381 }
2382
2383 if (t != NULL && t->is_Java_thread()) {
2384 JavaThread* thread = (JavaThread*) t;
2385 bool in_java = thread->thread_state() == _thread_in_Java;
2386
2387 // Handle potential stack overflows up front.
2388 if (exception_code == EXCEPTION_STACK_OVERFLOW) {
2389 if (thread->stack_guards_enabled()) {
2390 if (in_java) {
2391 frame fr;
2392 PEXCEPTION_RECORD exceptionRecord = exceptionInfo->ExceptionRecord;
2393 address addr = (address) exceptionRecord->ExceptionInformation[1];
2394 if (os::win32::get_frame_at_stack_banging_point(thread, exceptionInfo, pc, &fr)) {
2395 assert(fr.is_java_frame(), "Must be a Java frame");
2396 SharedRuntime::look_for_reserved_stack_annotated_method(thread, fr);
2397 }
2398 }
2399 // Yellow zone violation. The o/s has unprotected the first yellow
2400 // zone page for us. Note: must call disable_stack_yellow_zone to
2401 // update the enabled status, even if the zone contains only one page.
2402 assert(thread->thread_state() != _thread_in_vm, "Undersized StackShadowPages");
2403 thread->disable_stack_yellow_reserved_zone();
2404 // If not in java code, return and hope for the best.
2405 return in_java
2406 ? Handle_Exception(exceptionInfo, SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW))
2407 : EXCEPTION_CONTINUE_EXECUTION;
2408 } else {
2409 // Fatal red zone violation.
2410 thread->disable_stack_red_zone();
2411 tty->print_raw_cr("An unrecoverable stack overflow has occurred.");
2412 report_error(t, exception_code, pc, exceptionInfo->ExceptionRecord,
2413 exceptionInfo->ContextRecord);
2414 return EXCEPTION_CONTINUE_SEARCH;
2415 }
2416 } else if (exception_code == EXCEPTION_ACCESS_VIOLATION) {
2417 // Either stack overflow or null pointer exception.
2418 if (in_java) {
2419 PEXCEPTION_RECORD exceptionRecord = exceptionInfo->ExceptionRecord;
2420 address addr = (address) exceptionRecord->ExceptionInformation[1];
2421 address stack_end = thread->stack_end();
2422 if (addr < stack_end && addr >= stack_end - os::vm_page_size()) {
2423 // Stack overflow.
2424 assert(!os::uses_stack_guard_pages(),
2425 "should be caught by red zone code above.");
2426 return Handle_Exception(exceptionInfo,
2427 SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW));
2428 }
2429 // Check for safepoint polling and implicit null
2430 // We only expect null pointers in the stubs (vtable)
2431 // the rest are checked explicitly now.
2432 CodeBlob* cb = CodeCache::find_blob(pc);
2433 if (cb != NULL) {
2434 if (os::is_poll_address(addr)) {
2435 address stub = SharedRuntime::get_poll_stub(pc);
2436 return Handle_Exception(exceptionInfo, stub);
2437 }
2438 }
2439 {
2440 #ifdef _WIN64
2441 // If it's a legal stack address map the entire region in
2442 //
2443 PEXCEPTION_RECORD exceptionRecord = exceptionInfo->ExceptionRecord;
2444 address addr = (address) exceptionRecord->ExceptionInformation[1];
2445 if (addr > thread->stack_reserved_zone_base() && addr < thread->stack_base()) {
2446 addr = (address)((uintptr_t)addr &
2447 (~((uintptr_t)os::vm_page_size() - (uintptr_t)1)));
2448 os::commit_memory((char *)addr, thread->stack_base() - addr,
2449 !ExecMem);
2450 return EXCEPTION_CONTINUE_EXECUTION;
2451 } else
2452 #endif
2453 {
2454 // Null pointer exception.
2455 if (!MacroAssembler::needs_explicit_null_check((intptr_t)addr)) {
2456 address stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
2457 if (stub != NULL) return Handle_Exception(exceptionInfo, stub);
2458 }
2459 report_error(t, exception_code, pc, exceptionInfo->ExceptionRecord,
2460 exceptionInfo->ContextRecord);
2461 return EXCEPTION_CONTINUE_SEARCH;
2462 }
2463 }
2464 }
2465
2466 #ifdef _WIN64
2467 // Special care for fast JNI field accessors.
2468 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks
2469 // in and the heap gets shrunk before the field access.
2470 if (exception_code == EXCEPTION_ACCESS_VIOLATION) {
2471 address addr = JNI_FastGetField::find_slowcase_pc(pc);
2472 if (addr != (address)-1) {
2473 return Handle_Exception(exceptionInfo, addr);
2474 }
2475 }
2476 #endif
2477
2478 // Stack overflow or null pointer exception in native code.
2479 report_error(t, exception_code, pc, exceptionInfo->ExceptionRecord,
2480 exceptionInfo->ContextRecord);
2481 return EXCEPTION_CONTINUE_SEARCH;
2482 } // /EXCEPTION_ACCESS_VIOLATION
2483 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
2484
2485 if (in_java) {
2486 switch (exception_code) {
2487 case EXCEPTION_INT_DIVIDE_BY_ZERO:
2488 return Handle_Exception(exceptionInfo, SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO));
2489
2490 case EXCEPTION_INT_OVERFLOW:
2491 return Handle_IDiv_Exception(exceptionInfo);
2492
2493 } // switch
2494 }
2495 if (((thread->thread_state() == _thread_in_Java) ||
2496 (thread->thread_state() == _thread_in_native)) &&
2497 exception_code != EXCEPTION_UNCAUGHT_CXX_EXCEPTION) {
2498 LONG result=Handle_FLT_Exception(exceptionInfo);
2499 if (result==EXCEPTION_CONTINUE_EXECUTION) return result;
2500 }
2501 }
2502
2503 if (exception_code != EXCEPTION_BREAKPOINT) {
2504 report_error(t, exception_code, pc, exceptionInfo->ExceptionRecord,
2505 exceptionInfo->ContextRecord);
2506 }
2507 return EXCEPTION_CONTINUE_SEARCH;
2508 }
2509
2510 #ifndef _WIN64
2511 // Special care for fast JNI accessors.
2512 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in and
2513 // the heap gets shrunk before the field access.
2514 // Need to install our own structured exception handler since native code may
2515 // install its own.
2516 LONG WINAPI fastJNIAccessorExceptionFilter(struct _EXCEPTION_POINTERS* exceptionInfo) {
2517 DWORD exception_code = exceptionInfo->ExceptionRecord->ExceptionCode;
2518 if (exception_code == EXCEPTION_ACCESS_VIOLATION) {
2519 address pc = (address) exceptionInfo->ContextRecord->Eip;
2520 address addr = JNI_FastGetField::find_slowcase_pc(pc);
2521 if (addr != (address)-1) {
2522 return Handle_Exception(exceptionInfo, addr);
2523 }
2524 }
2525 return EXCEPTION_CONTINUE_SEARCH;
2526 }
2527
2528 #define DEFINE_FAST_GETFIELD(Return, Fieldname, Result) \
2529 Return JNICALL jni_fast_Get##Result##Field_wrapper(JNIEnv *env, \
2530 jobject obj, \
2531 jfieldID fieldID) { \
2532 __try { \
2533 return (*JNI_FastGetField::jni_fast_Get##Result##Field_fp)(env, \
2534 obj, \
2535 fieldID); \
2536 } __except(fastJNIAccessorExceptionFilter((_EXCEPTION_POINTERS*) \
2537 _exception_info())) { \
2538 } \
2539 return 0; \
2540 }
2541
2542 DEFINE_FAST_GETFIELD(jboolean, bool, Boolean)
2543 DEFINE_FAST_GETFIELD(jbyte, byte, Byte)
2544 DEFINE_FAST_GETFIELD(jchar, char, Char)
2545 DEFINE_FAST_GETFIELD(jshort, short, Short)
2546 DEFINE_FAST_GETFIELD(jint, int, Int)
2547 DEFINE_FAST_GETFIELD(jlong, long, Long)
2548 DEFINE_FAST_GETFIELD(jfloat, float, Float)
2549 DEFINE_FAST_GETFIELD(jdouble, double, Double)
2550
2551 address os::win32::fast_jni_accessor_wrapper(BasicType type) {
2552 switch (type) {
2553 case T_BOOLEAN: return (address)jni_fast_GetBooleanField_wrapper;
2554 case T_BYTE: return (address)jni_fast_GetByteField_wrapper;
2555 case T_CHAR: return (address)jni_fast_GetCharField_wrapper;
2556 case T_SHORT: return (address)jni_fast_GetShortField_wrapper;
2557 case T_INT: return (address)jni_fast_GetIntField_wrapper;
2558 case T_LONG: return (address)jni_fast_GetLongField_wrapper;
2559 case T_FLOAT: return (address)jni_fast_GetFloatField_wrapper;
2560 case T_DOUBLE: return (address)jni_fast_GetDoubleField_wrapper;
2561 default: ShouldNotReachHere();
2562 }
2563 return (address)-1;
2564 }
2565 #endif
2566
2567 // Virtual Memory
2568
2569 int os::vm_page_size() { return os::win32::vm_page_size(); }
2570 int os::vm_allocation_granularity() {
2571 return os::win32::vm_allocation_granularity();
2572 }
2573
2574 // Windows large page support is available on Windows 2003. In order to use
2575 // large page memory, the administrator must first assign additional privilege
2576 // to the user:
2577 // + select Control Panel -> Administrative Tools -> Local Security Policy
2578 // + select Local Policies -> User Rights Assignment
2579 // + double click "Lock pages in memory", add users and/or groups
2580 // + reboot
2581 // Note the above steps are needed for administrator as well, as administrators
2582 // by default do not have the privilege to lock pages in memory.
2583 //
2584 // Note about Windows 2003: although the API supports committing large page
2585 // memory on a page-by-page basis and VirtualAlloc() returns success under this
2586 // scenario, I found through experiment it only uses large page if the entire
2587 // memory region is reserved and committed in a single VirtualAlloc() call.
2588 // This makes Windows large page support more or less like Solaris ISM, in
2589 // that the entire heap must be committed upfront. This probably will change
2590 // in the future, if so the code below needs to be revisited.
2591
2592 #ifndef MEM_LARGE_PAGES
2593 #define MEM_LARGE_PAGES 0x20000000
2594 #endif
2595
2596 static HANDLE _hProcess;
2597 static HANDLE _hToken;
2598
2599 // Container for NUMA node list info
2600 class NUMANodeListHolder {
2601 private:
2602 int *_numa_used_node_list; // allocated below
2603 int _numa_used_node_count;
2604
2605 void free_node_list() {
2606 if (_numa_used_node_list != NULL) {
2607 FREE_C_HEAP_ARRAY(int, _numa_used_node_list);
2608 }
2609 }
2610
2611 public:
2612 NUMANodeListHolder() {
2613 _numa_used_node_count = 0;
2614 _numa_used_node_list = NULL;
2615 // do rest of initialization in build routine (after function pointers are set up)
2616 }
2617
2618 ~NUMANodeListHolder() {
2619 free_node_list();
2620 }
2621
2622 bool build() {
2623 DWORD_PTR proc_aff_mask;
2624 DWORD_PTR sys_aff_mask;
2625 if (!GetProcessAffinityMask(GetCurrentProcess(), &proc_aff_mask, &sys_aff_mask)) return false;
2626 ULONG highest_node_number;
2627 if (!GetNumaHighestNodeNumber(&highest_node_number)) return false;
2628 free_node_list();
2629 _numa_used_node_list = NEW_C_HEAP_ARRAY(int, highest_node_number + 1, mtInternal);
2630 for (unsigned int i = 0; i <= highest_node_number; i++) {
2631 ULONGLONG proc_mask_numa_node;
2632 if (!GetNumaNodeProcessorMask(i, &proc_mask_numa_node)) return false;
2633 if ((proc_aff_mask & proc_mask_numa_node)!=0) {
2634 _numa_used_node_list[_numa_used_node_count++] = i;
2635 }
2636 }
2637 return (_numa_used_node_count > 1);
2638 }
2639
2640 int get_count() { return _numa_used_node_count; }
2641 int get_node_list_entry(int n) {
2642 // for indexes out of range, returns -1
2643 return (n < _numa_used_node_count ? _numa_used_node_list[n] : -1);
2644 }
2645
2646 } numa_node_list_holder;
2647
2648
2649
2650 static size_t _large_page_size = 0;
2651
2652 static bool request_lock_memory_privilege() {
2653 _hProcess = OpenProcess(PROCESS_QUERY_INFORMATION, FALSE,
2654 os::current_process_id());
2655
2656 LUID luid;
2657 if (_hProcess != NULL &&
2658 OpenProcessToken(_hProcess, TOKEN_ADJUST_PRIVILEGES, &_hToken) &&
2659 LookupPrivilegeValue(NULL, "SeLockMemoryPrivilege", &luid)) {
2660
2661 TOKEN_PRIVILEGES tp;
2662 tp.PrivilegeCount = 1;
2663 tp.Privileges[0].Luid = luid;
2664 tp.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED;
2665
2666 // AdjustTokenPrivileges() may return TRUE even when it couldn't change the
2667 // privilege. Check GetLastError() too. See MSDN document.
2668 if (AdjustTokenPrivileges(_hToken, false, &tp, sizeof(tp), NULL, NULL) &&
2669 (GetLastError() == ERROR_SUCCESS)) {
2670 return true;
2671 }
2672 }
2673
2674 return false;
2675 }
2676
2677 static void cleanup_after_large_page_init() {
2678 if (_hProcess) CloseHandle(_hProcess);
2679 _hProcess = NULL;
2680 if (_hToken) CloseHandle(_hToken);
2681 _hToken = NULL;
2682 }
2683
2684 static bool numa_interleaving_init() {
2685 bool success = false;
2686 bool use_numa_interleaving_specified = !FLAG_IS_DEFAULT(UseNUMAInterleaving);
2687
2688 // print a warning if UseNUMAInterleaving flag is specified on command line
2689 bool warn_on_failure = use_numa_interleaving_specified;
2690 #define WARN(msg) if (warn_on_failure) { warning(msg); }
2691
2692 // NUMAInterleaveGranularity cannot be less than vm_allocation_granularity (or _large_page_size if using large pages)
2693 size_t min_interleave_granularity = UseLargePages ? _large_page_size : os::vm_allocation_granularity();
2694 NUMAInterleaveGranularity = align_up(NUMAInterleaveGranularity, min_interleave_granularity);
2695
2696 if (numa_node_list_holder.build()) {
2697 if (log_is_enabled(Debug, os, cpu)) {
2698 Log(os, cpu) log;
2699 log.debug("NUMA UsedNodeCount=%d, namely ", numa_node_list_holder.get_count());
2700 for (int i = 0; i < numa_node_list_holder.get_count(); i++) {
2701 log.debug(" %d ", numa_node_list_holder.get_node_list_entry(i));
2702 }
2703 }
2704 success = true;
2705 } else {
2706 WARN("Process does not cover multiple NUMA nodes.");
2707 }
2708 if (!success) {
2709 if (use_numa_interleaving_specified) WARN("...Ignoring UseNUMAInterleaving flag.");
2710 }
2711 return success;
2712 #undef WARN
2713 }
2714
2715 // this routine is used whenever we need to reserve a contiguous VA range
2716 // but we need to make separate VirtualAlloc calls for each piece of the range
2717 // Reasons for doing this:
2718 // * UseLargePagesIndividualAllocation was set (normally only needed on WS2003 but possible to be set otherwise)
2719 // * UseNUMAInterleaving requires a separate node for each piece
2720 static char* allocate_pages_individually(size_t bytes, char* addr, DWORD flags,
2721 DWORD prot,
2722 bool should_inject_error = false) {
2723 char * p_buf;
2724 // note: at setup time we guaranteed that NUMAInterleaveGranularity was aligned up to a page size
2725 size_t page_size = UseLargePages ? _large_page_size : os::vm_allocation_granularity();
2726 size_t chunk_size = UseNUMAInterleaving ? NUMAInterleaveGranularity : page_size;
2727
2728 // first reserve enough address space in advance since we want to be
2729 // able to break a single contiguous virtual address range into multiple
2730 // large page commits but WS2003 does not allow reserving large page space
2731 // so we just use 4K pages for reserve, this gives us a legal contiguous
2732 // address space. then we will deallocate that reservation, and re alloc
2733 // using large pages
2734 const size_t size_of_reserve = bytes + chunk_size;
2735 if (bytes > size_of_reserve) {
2736 // Overflowed.
2737 return NULL;
2738 }
2739 p_buf = (char *) VirtualAlloc(addr,
2740 size_of_reserve, // size of Reserve
2741 MEM_RESERVE,
2742 PAGE_READWRITE);
2743 // If reservation failed, return NULL
2744 if (p_buf == NULL) return NULL;
2745 MemTracker::record_virtual_memory_reserve((address)p_buf, size_of_reserve, CALLER_PC);
2746 os::release_memory(p_buf, bytes + chunk_size);
2747
2748 // we still need to round up to a page boundary (in case we are using large pages)
2749 // but not to a chunk boundary (in case InterleavingGranularity doesn't align with page size)
2750 // instead we handle this in the bytes_to_rq computation below
2751 p_buf = align_up(p_buf, page_size);
2752
2753 // now go through and allocate one chunk at a time until all bytes are
2754 // allocated
2755 size_t bytes_remaining = bytes;
2756 // An overflow of align_up() would have been caught above
2757 // in the calculation of size_of_reserve.
2758 char * next_alloc_addr = p_buf;
2759 HANDLE hProc = GetCurrentProcess();
2760
2761 #ifdef ASSERT
2762 // Variable for the failure injection
2763 int ran_num = os::random();
2764 size_t fail_after = ran_num % bytes;
2765 #endif
2766
2767 int count=0;
2768 while (bytes_remaining) {
2769 // select bytes_to_rq to get to the next chunk_size boundary
2770
2771 size_t bytes_to_rq = MIN2(bytes_remaining, chunk_size - ((size_t)next_alloc_addr % chunk_size));
2772 // Note allocate and commit
2773 char * p_new;
2774
2775 #ifdef ASSERT
2776 bool inject_error_now = should_inject_error && (bytes_remaining <= fail_after);
2777 #else
2778 const bool inject_error_now = false;
2779 #endif
2780
2781 if (inject_error_now) {
2782 p_new = NULL;
2783 } else {
2784 if (!UseNUMAInterleaving) {
2785 p_new = (char *) VirtualAlloc(next_alloc_addr,
2786 bytes_to_rq,
2787 flags,
2788 prot);
2789 } else {
2790 // get the next node to use from the used_node_list
2791 assert(numa_node_list_holder.get_count() > 0, "Multiple NUMA nodes expected");
2792 DWORD node = numa_node_list_holder.get_node_list_entry(count % numa_node_list_holder.get_count());
2793 p_new = (char *)VirtualAllocExNuma(hProc, next_alloc_addr, bytes_to_rq, flags, prot, node);
2794 }
2795 }
2796
2797 if (p_new == NULL) {
2798 // Free any allocated pages
2799 if (next_alloc_addr > p_buf) {
2800 // Some memory was committed so release it.
2801 size_t bytes_to_release = bytes - bytes_remaining;
2802 // NMT has yet to record any individual blocks, so it
2803 // need to create a dummy 'reserve' record to match
2804 // the release.
2805 MemTracker::record_virtual_memory_reserve((address)p_buf,
2806 bytes_to_release, CALLER_PC);
2807 os::release_memory(p_buf, bytes_to_release);
2808 }
2809 #ifdef ASSERT
2810 if (should_inject_error) {
2811 log_develop_debug(pagesize)("Reserving pages individually failed.");
2812 }
2813 #endif
2814 return NULL;
2815 }
2816
2817 bytes_remaining -= bytes_to_rq;
2818 next_alloc_addr += bytes_to_rq;
2819 count++;
2820 }
2821 // Although the memory is allocated individually, it is returned as one.
2822 // NMT records it as one block.
2823 if ((flags & MEM_COMMIT) != 0) {
2824 MemTracker::record_virtual_memory_reserve_and_commit((address)p_buf, bytes, CALLER_PC);
2825 } else {
2826 MemTracker::record_virtual_memory_reserve((address)p_buf, bytes, CALLER_PC);
2827 }
2828
2829 // made it this far, success
2830 return p_buf;
2831 }
2832
2833
2834
2835 void os::large_page_init() {
2836 if (!UseLargePages) return;
2837
2838 // print a warning if any large page related flag is specified on command line
2839 bool warn_on_failure = !FLAG_IS_DEFAULT(UseLargePages) ||
2840 !FLAG_IS_DEFAULT(LargePageSizeInBytes);
2841 bool success = false;
2842
2843 #define WARN(msg) if (warn_on_failure) { warning(msg); }
2844 if (request_lock_memory_privilege()) {
2845 size_t s = GetLargePageMinimum();
2846 if (s) {
2847 #if defined(IA32) || defined(AMD64)
2848 if (s > 4*M || LargePageSizeInBytes > 4*M) {
2849 WARN("JVM cannot use large pages bigger than 4mb.");
2850 } else {
2851 #endif
2852 if (LargePageSizeInBytes && LargePageSizeInBytes % s == 0) {
2853 _large_page_size = LargePageSizeInBytes;
2854 } else {
2855 _large_page_size = s;
2856 }
2857 success = true;
2858 #if defined(IA32) || defined(AMD64)
2859 }
2860 #endif
2861 } else {
2862 WARN("Large page is not supported by the processor.");
2863 }
2864 } else {
2865 WARN("JVM cannot use large page memory because it does not have enough privilege to lock pages in memory.");
2866 }
2867 #undef WARN
2868
2869 const size_t default_page_size = (size_t) vm_page_size();
2870 if (success && _large_page_size > default_page_size) {
2871 _page_sizes[0] = _large_page_size;
2872 _page_sizes[1] = default_page_size;
2873 _page_sizes[2] = 0;
2874 }
2875
2876 cleanup_after_large_page_init();
2877 UseLargePages = success;
2878 }
2879
2880 // On win32, one cannot release just a part of reserved memory, it's an
2881 // all or nothing deal. When we split a reservation, we must break the
2882 // reservation into two reservations.
2883 void os::pd_split_reserved_memory(char *base, size_t size, size_t split,
2884 bool realloc) {
2885 if (size > 0) {
2886 release_memory(base, size);
2887 if (realloc) {
2888 reserve_memory(split, base);
2889 }
2890 if (size != split) {
2891 reserve_memory(size - split, base + split);
2892 }
2893 }
2894 }
2895
2896 // Multiple threads can race in this code but it's not possible to unmap small sections of
2897 // virtual space to get requested alignment, like posix-like os's.
2898 // Windows prevents multiple thread from remapping over each other so this loop is thread-safe.
2899 char* os::reserve_memory_aligned(size_t size, size_t alignment) {
2900 assert((alignment & (os::vm_allocation_granularity() - 1)) == 0,
2901 "Alignment must be a multiple of allocation granularity (page size)");
2902 assert((size & (alignment -1)) == 0, "size must be 'alignment' aligned");
2903
2904 size_t extra_size = size + alignment;
2905 assert(extra_size >= size, "overflow, size is too large to allow alignment");
2906
2907 char* aligned_base = NULL;
2908
2909 do {
2910 char* extra_base = os::reserve_memory(extra_size, NULL, alignment);
2911 if (extra_base == NULL) {
2912 return NULL;
2913 }
2914 // Do manual alignment
2915 aligned_base = align_up(extra_base, alignment);
2916
2917 os::release_memory(extra_base, extra_size);
2918
2919 aligned_base = os::reserve_memory(size, aligned_base);
2920
2921 } while (aligned_base == NULL);
2922
2923 return aligned_base;
2924 }
2925
2926 char* os::pd_reserve_memory(size_t bytes, char* addr, size_t alignment_hint) {
2927 assert((size_t)addr % os::vm_allocation_granularity() == 0,
2928 "reserve alignment");
2929 assert(bytes % os::vm_page_size() == 0, "reserve page size");
2930 char* res;
2931 // note that if UseLargePages is on, all the areas that require interleaving
2932 // will go thru reserve_memory_special rather than thru here.
2933 bool use_individual = (UseNUMAInterleaving && !UseLargePages);
2934 if (!use_individual) {
2935 res = (char*)VirtualAlloc(addr, bytes, MEM_RESERVE, PAGE_READWRITE);
2936 } else {
2937 elapsedTimer reserveTimer;
2938 if (Verbose && PrintMiscellaneous) reserveTimer.start();
2939 // in numa interleaving, we have to allocate pages individually
2940 // (well really chunks of NUMAInterleaveGranularity size)
2941 res = allocate_pages_individually(bytes, addr, MEM_RESERVE, PAGE_READWRITE);
2942 if (res == NULL) {
2943 warning("NUMA page allocation failed");
2944 }
2945 if (Verbose && PrintMiscellaneous) {
2946 reserveTimer.stop();
2947 tty->print_cr("reserve_memory of %Ix bytes took " JLONG_FORMAT " ms (" JLONG_FORMAT " ticks)", bytes,
2948 reserveTimer.milliseconds(), reserveTimer.ticks());
2949 }
2950 }
2951 assert(res == NULL || addr == NULL || addr == res,
2952 "Unexpected address from reserve.");
2953
2954 return res;
2955 }
2956
2957 // Reserve memory at an arbitrary address, only if that area is
2958 // available (and not reserved for something else).
2959 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2960 // Windows os::reserve_memory() fails of the requested address range is
2961 // not avilable.
2962 return reserve_memory(bytes, requested_addr);
2963 }
2964
2965 size_t os::large_page_size() {
2966 return _large_page_size;
2967 }
2968
2969 bool os::can_commit_large_page_memory() {
2970 // Windows only uses large page memory when the entire region is reserved
2971 // and committed in a single VirtualAlloc() call. This may change in the
2972 // future, but with Windows 2003 it's not possible to commit on demand.
2973 return false;
2974 }
2975
2976 bool os::can_execute_large_page_memory() {
2977 return true;
2978 }
2979
2980 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* addr,
2981 bool exec) {
2982 assert(UseLargePages, "only for large pages");
2983
2984 if (!is_aligned(bytes, os::large_page_size()) || alignment > os::large_page_size()) {
2985 return NULL; // Fallback to small pages.
2986 }
2987
2988 const DWORD prot = exec ? PAGE_EXECUTE_READWRITE : PAGE_READWRITE;
2989 const DWORD flags = MEM_RESERVE | MEM_COMMIT | MEM_LARGE_PAGES;
2990
2991 // with large pages, there are two cases where we need to use Individual Allocation
2992 // 1) the UseLargePagesIndividualAllocation flag is set (set by default on WS2003)
2993 // 2) NUMA Interleaving is enabled, in which case we use a different node for each page
2994 if (UseLargePagesIndividualAllocation || UseNUMAInterleaving) {
2995 log_debug(pagesize)("Reserving large pages individually.");
2996
2997 char * p_buf = allocate_pages_individually(bytes, addr, flags, prot, LargePagesIndividualAllocationInjectError);
2998 if (p_buf == NULL) {
2999 // give an appropriate warning message
3000 if (UseNUMAInterleaving) {
3001 warning("NUMA large page allocation failed, UseLargePages flag ignored");
3002 }
3003 if (UseLargePagesIndividualAllocation) {
3004 warning("Individually allocated large pages failed, "
3005 "use -XX:-UseLargePagesIndividualAllocation to turn off");
3006 }
3007 return NULL;
3008 }
3009
3010 return p_buf;
3011
3012 } else {
3013 log_debug(pagesize)("Reserving large pages in a single large chunk.");
3014
3015 // normal policy just allocate it all at once
3016 DWORD flag = MEM_RESERVE | MEM_COMMIT | MEM_LARGE_PAGES;
3017 char * res = (char *)VirtualAlloc(addr, bytes, flag, prot);
3018 if (res != NULL) {
3019 MemTracker::record_virtual_memory_reserve_and_commit((address)res, bytes, CALLER_PC);
3020 }
3021
3022 return res;
3023 }
3024 }
3025
3026 bool os::release_memory_special(char* base, size_t bytes) {
3027 assert(base != NULL, "Sanity check");
3028 return release_memory(base, bytes);
3029 }
3030
3031 void os::print_statistics() {
3032 }
3033
3034 static void warn_fail_commit_memory(char* addr, size_t bytes, bool exec) {
3035 int err = os::get_last_error();
3036 char buf[256];
3037 size_t buf_len = os::lasterror(buf, sizeof(buf));
3038 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT
3039 ", %d) failed; error='%s' (DOS error/errno=%d)", addr, bytes,
3040 exec, buf_len != 0 ? buf : "<no_error_string>", err);
3041 }
3042
3043 bool os::pd_commit_memory(char* addr, size_t bytes, bool exec) {
3044 if (bytes == 0) {
3045 // Don't bother the OS with noops.
3046 return true;
3047 }
3048 assert((size_t) addr % os::vm_page_size() == 0, "commit on page boundaries");
3049 assert(bytes % os::vm_page_size() == 0, "commit in page-sized chunks");
3050 // Don't attempt to print anything if the OS call fails. We're
3051 // probably low on resources, so the print itself may cause crashes.
3052
3053 // unless we have NUMAInterleaving enabled, the range of a commit
3054 // is always within a reserve covered by a single VirtualAlloc
3055 // in that case we can just do a single commit for the requested size
3056 if (!UseNUMAInterleaving) {
3057 if (VirtualAlloc(addr, bytes, MEM_COMMIT, PAGE_READWRITE) == NULL) {
3058 NOT_PRODUCT(warn_fail_commit_memory(addr, bytes, exec);)
3059 return false;
3060 }
3061 if (exec) {
3062 DWORD oldprot;
3063 // Windows doc says to use VirtualProtect to get execute permissions
3064 if (!VirtualProtect(addr, bytes, PAGE_EXECUTE_READWRITE, &oldprot)) {
3065 NOT_PRODUCT(warn_fail_commit_memory(addr, bytes, exec);)
3066 return false;
3067 }
3068 }
3069 return true;
3070 } else {
3071
3072 // when NUMAInterleaving is enabled, the commit might cover a range that
3073 // came from multiple VirtualAlloc reserves (using allocate_pages_individually).
3074 // VirtualQuery can help us determine that. The RegionSize that VirtualQuery
3075 // returns represents the number of bytes that can be committed in one step.
3076 size_t bytes_remaining = bytes;
3077 char * next_alloc_addr = addr;
3078 while (bytes_remaining > 0) {
3079 MEMORY_BASIC_INFORMATION alloc_info;
3080 VirtualQuery(next_alloc_addr, &alloc_info, sizeof(alloc_info));
3081 size_t bytes_to_rq = MIN2(bytes_remaining, (size_t)alloc_info.RegionSize);
3082 if (VirtualAlloc(next_alloc_addr, bytes_to_rq, MEM_COMMIT,
3083 PAGE_READWRITE) == NULL) {
3084 NOT_PRODUCT(warn_fail_commit_memory(next_alloc_addr, bytes_to_rq,
3085 exec);)
3086 return false;
3087 }
3088 if (exec) {
3089 DWORD oldprot;
3090 if (!VirtualProtect(next_alloc_addr, bytes_to_rq,
3091 PAGE_EXECUTE_READWRITE, &oldprot)) {
3092 NOT_PRODUCT(warn_fail_commit_memory(next_alloc_addr, bytes_to_rq,
3093 exec);)
3094 return false;
3095 }
3096 }
3097 bytes_remaining -= bytes_to_rq;
3098 next_alloc_addr += bytes_to_rq;
3099 }
3100 }
3101 // if we made it this far, return true
3102 return true;
3103 }
3104
3105 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
3106 bool exec) {
3107 // alignment_hint is ignored on this OS
3108 return pd_commit_memory(addr, size, exec);
3109 }
3110
3111 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
3112 const char* mesg) {
3113 assert(mesg != NULL, "mesg must be specified");
3114 if (!pd_commit_memory(addr, size, exec)) {
3115 warn_fail_commit_memory(addr, size, exec);
3116 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, "%s", mesg);
3117 }
3118 }
3119
3120 void os::pd_commit_memory_or_exit(char* addr, size_t size,
3121 size_t alignment_hint, bool exec,
3122 const char* mesg) {
3123 // alignment_hint is ignored on this OS
3124 pd_commit_memory_or_exit(addr, size, exec, mesg);
3125 }
3126
3127 bool os::pd_uncommit_memory(char* addr, size_t bytes) {
3128 if (bytes == 0) {
3129 // Don't bother the OS with noops.
3130 return true;
3131 }
3132 assert((size_t) addr % os::vm_page_size() == 0, "uncommit on page boundaries");
3133 assert(bytes % os::vm_page_size() == 0, "uncommit in page-sized chunks");
3134 return (VirtualFree(addr, bytes, MEM_DECOMMIT) != 0);
3135 }
3136
3137 bool os::pd_release_memory(char* addr, size_t bytes) {
3138 return VirtualFree(addr, 0, MEM_RELEASE) != 0;
3139 }
3140
3141 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
3142 return os::commit_memory(addr, size, !ExecMem);
3143 }
3144
3145 bool os::remove_stack_guard_pages(char* addr, size_t size) {
3146 return os::uncommit_memory(addr, size);
3147 }
3148
3149 static bool protect_pages_individually(char* addr, size_t bytes, unsigned int p, DWORD *old_status) {
3150 uint count = 0;
3151 bool ret = false;
3152 size_t bytes_remaining = bytes;
3153 char * next_protect_addr = addr;
3154
3155 // Use VirtualQuery() to get the chunk size.
3156 while (bytes_remaining) {
3157 MEMORY_BASIC_INFORMATION alloc_info;
3158 if (VirtualQuery(next_protect_addr, &alloc_info, sizeof(alloc_info)) == 0) {
3159 return false;
3160 }
3161
3162 size_t bytes_to_protect = MIN2(bytes_remaining, (size_t)alloc_info.RegionSize);
3163 // We used different API at allocate_pages_individually() based on UseNUMAInterleaving,
3164 // but we don't distinguish here as both cases are protected by same API.
3165 ret = VirtualProtect(next_protect_addr, bytes_to_protect, p, old_status) != 0;
3166 warning("Failed protecting pages individually for chunk #%u", count);
3167 if (!ret) {
3168 return false;
3169 }
3170
3171 bytes_remaining -= bytes_to_protect;
3172 next_protect_addr += bytes_to_protect;
3173 count++;
3174 }
3175 return ret;
3176 }
3177
3178 // Set protections specified
3179 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
3180 bool is_committed) {
3181 unsigned int p = 0;
3182 switch (prot) {
3183 case MEM_PROT_NONE: p = PAGE_NOACCESS; break;
3184 case MEM_PROT_READ: p = PAGE_READONLY; break;
3185 case MEM_PROT_RW: p = PAGE_READWRITE; break;
3186 case MEM_PROT_RWX: p = PAGE_EXECUTE_READWRITE; break;
3187 default:
3188 ShouldNotReachHere();
3189 }
3190
3191 DWORD old_status;
3192
3193 // Strange enough, but on Win32 one can change protection only for committed
3194 // memory, not a big deal anyway, as bytes less or equal than 64K
3195 if (!is_committed) {
3196 commit_memory_or_exit(addr, bytes, prot == MEM_PROT_RWX,
3197 "cannot commit protection page");
3198 }
3199 // One cannot use os::guard_memory() here, as on Win32 guard page
3200 // have different (one-shot) semantics, from MSDN on PAGE_GUARD:
3201 //
3202 // Pages in the region become guard pages. Any attempt to access a guard page
3203 // causes the system to raise a STATUS_GUARD_PAGE exception and turn off
3204 // the guard page status. Guard pages thus act as a one-time access alarm.
3205 bool ret;
3206 if (UseNUMAInterleaving) {
3207 // If UseNUMAInterleaving is enabled, the pages may have been allocated a chunk at a time,
3208 // so we must protect the chunks individually.
3209 ret = protect_pages_individually(addr, bytes, p, &old_status);
3210 } else {
3211 ret = VirtualProtect(addr, bytes, p, &old_status) != 0;
3212 }
3213 #ifdef ASSERT
3214 if (!ret) {
3215 int err = os::get_last_error();
3216 char buf[256];
3217 size_t buf_len = os::lasterror(buf, sizeof(buf));
3218 warning("INFO: os::protect_memory(" PTR_FORMAT ", " SIZE_FORMAT
3219 ") failed; error='%s' (DOS error/errno=%d)", addr, bytes,
3220 buf_len != 0 ? buf : "<no_error_string>", err);
3221 }
3222 #endif
3223 return ret;
3224 }
3225
3226 bool os::guard_memory(char* addr, size_t bytes) {
3227 DWORD old_status;
3228 return VirtualProtect(addr, bytes, PAGE_READWRITE | PAGE_GUARD, &old_status) != 0;
3229 }
3230
3231 bool os::unguard_memory(char* addr, size_t bytes) {
3232 DWORD old_status;
3233 return VirtualProtect(addr, bytes, PAGE_READWRITE, &old_status) != 0;
3234 }
3235
3236 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) { }
3237 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) { }
3238 void os::numa_make_global(char *addr, size_t bytes) { }
3239 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) { }
3240 bool os::numa_topology_changed() { return false; }
3241 size_t os::numa_get_groups_num() { return MAX2(numa_node_list_holder.get_count(), 1); }
3242 int os::numa_get_group_id() { return 0; }
3243 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
3244 if (numa_node_list_holder.get_count() == 0 && size > 0) {
3245 // Provide an answer for UMA systems
3246 ids[0] = 0;
3247 return 1;
3248 } else {
3249 // check for size bigger than actual groups_num
3250 size = MIN2(size, numa_get_groups_num());
3251 for (int i = 0; i < (int)size; i++) {
3252 ids[i] = numa_node_list_holder.get_node_list_entry(i);
3253 }
3254 return size;
3255 }
3256 }
3257
3258 bool os::get_page_info(char *start, page_info* info) {
3259 return false;
3260 }
3261
3262 char *os::scan_pages(char *start, char* end, page_info* page_expected,
3263 page_info* page_found) {
3264 return end;
3265 }
3266
3267 char* os::non_memory_address_word() {
3268 // Must never look like an address returned by reserve_memory,
3269 // even in its subfields (as defined by the CPU immediate fields,
3270 // if the CPU splits constants across multiple instructions).
3271 return (char*)-1;
3272 }
3273
3274 #define MAX_ERROR_COUNT 100
3275 #define SYS_THREAD_ERROR 0xffffffffUL
3276
3277 void os::pd_start_thread(Thread* thread) {
3278 DWORD ret = ResumeThread(thread->osthread()->thread_handle());
3279 // Returns previous suspend state:
3280 // 0: Thread was not suspended
3281 // 1: Thread is running now
3282 // >1: Thread is still suspended.
3283 assert(ret != SYS_THREAD_ERROR, "StartThread failed"); // should propagate back
3284 }
3285
3286 class HighResolutionInterval : public CHeapObj<mtThread> {
3287 // The default timer resolution seems to be 10 milliseconds.
3288 // (Where is this written down?)
3289 // If someone wants to sleep for only a fraction of the default,
3290 // then we set the timer resolution down to 1 millisecond for
3291 // the duration of their interval.
3292 // We carefully set the resolution back, since otherwise we
3293 // seem to incur an overhead (3%?) that we don't need.
3294 // CONSIDER: if ms is small, say 3, then we should run with a high resolution time.
3295 // Buf if ms is large, say 500, or 503, we should avoid the call to timeBeginPeriod().
3296 // Alternatively, we could compute the relative error (503/500 = .6%) and only use
3297 // timeBeginPeriod() if the relative error exceeded some threshold.
3298 // timeBeginPeriod() has been linked to problems with clock drift on win32 systems and
3299 // to decreased efficiency related to increased timer "tick" rates. We want to minimize
3300 // (a) calls to timeBeginPeriod() and timeEndPeriod() and (b) time spent with high
3301 // resolution timers running.
3302 private:
3303 jlong resolution;
3304 public:
3305 HighResolutionInterval(jlong ms) {
3306 resolution = ms % 10L;
3307 if (resolution != 0) {
3308 MMRESULT result = timeBeginPeriod(1L);
3309 }
3310 }
3311 ~HighResolutionInterval() {
3312 if (resolution != 0) {
3313 MMRESULT result = timeEndPeriod(1L);
3314 }
3315 resolution = 0L;
3316 }
3317 };
3318
3319 int os::sleep(Thread* thread, jlong ms, bool interruptable) {
3320 jlong limit = (jlong) MAXDWORD;
3321
3322 while (ms > limit) {
3323 int res;
3324 if ((res = sleep(thread, limit, interruptable)) != OS_TIMEOUT) {
3325 return res;
3326 }
3327 ms -= limit;
3328 }
3329
3330 assert(thread == Thread::current(), "thread consistency check");
3331 OSThread* osthread = thread->osthread();
3332 OSThreadWaitState osts(osthread, false /* not Object.wait() */);
3333 int result;
3334 if (interruptable) {
3335 assert(thread->is_Java_thread(), "must be java thread");
3336 JavaThread *jt = (JavaThread *) thread;
3337 ThreadBlockInVM tbivm(jt);
3338
3339 jt->set_suspend_equivalent();
3340 // cleared by handle_special_suspend_equivalent_condition() or
3341 // java_suspend_self() via check_and_wait_while_suspended()
3342
3343 HANDLE events[1];
3344 events[0] = osthread->interrupt_event();
3345 HighResolutionInterval *phri=NULL;
3346 if (!ForceTimeHighResolution) {
3347 phri = new HighResolutionInterval(ms);
3348 }
3349 if (WaitForMultipleObjects(1, events, FALSE, (DWORD)ms) == WAIT_TIMEOUT) {
3350 result = OS_TIMEOUT;
3351 } else {
3352 ResetEvent(osthread->interrupt_event());
3353 osthread->set_interrupted(false);
3354 result = OS_INTRPT;
3355 }
3356 delete phri; //if it is NULL, harmless
3357
3358 // were we externally suspended while we were waiting?
3359 jt->check_and_wait_while_suspended();
3360 } else {
3361 assert(!thread->is_Java_thread(), "must not be java thread");
3362 Sleep((long) ms);
3363 result = OS_TIMEOUT;
3364 }
3365 return result;
3366 }
3367
3368 // Short sleep, direct OS call.
3369 //
3370 // ms = 0, means allow others (if any) to run.
3371 //
3372 void os::naked_short_sleep(jlong ms) {
3373 assert(ms < 1000, "Un-interruptable sleep, short time use only");
3374 Sleep(ms);
3375 }
3376
3377 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
3378 void os::infinite_sleep() {
3379 while (true) { // sleep forever ...
3380 Sleep(100000); // ... 100 seconds at a time
3381 }
3382 }
3383
3384 typedef BOOL (WINAPI * STTSignature)(void);
3385
3386 void os::naked_yield() {
3387 // Consider passing back the return value from SwitchToThread().
3388 SwitchToThread();
3389 }
3390
3391 // Win32 only gives you access to seven real priorities at a time,
3392 // so we compress Java's ten down to seven. It would be better
3393 // if we dynamically adjusted relative priorities.
3394
3395 int os::java_to_os_priority[CriticalPriority + 1] = {
3396 THREAD_PRIORITY_IDLE, // 0 Entry should never be used
3397 THREAD_PRIORITY_LOWEST, // 1 MinPriority
3398 THREAD_PRIORITY_LOWEST, // 2
3399 THREAD_PRIORITY_BELOW_NORMAL, // 3
3400 THREAD_PRIORITY_BELOW_NORMAL, // 4
3401 THREAD_PRIORITY_NORMAL, // 5 NormPriority
3402 THREAD_PRIORITY_NORMAL, // 6
3403 THREAD_PRIORITY_ABOVE_NORMAL, // 7
3404 THREAD_PRIORITY_ABOVE_NORMAL, // 8
3405 THREAD_PRIORITY_HIGHEST, // 9 NearMaxPriority
3406 THREAD_PRIORITY_HIGHEST, // 10 MaxPriority
3407 THREAD_PRIORITY_HIGHEST // 11 CriticalPriority
3408 };
3409
3410 int prio_policy1[CriticalPriority + 1] = {
3411 THREAD_PRIORITY_IDLE, // 0 Entry should never be used
3412 THREAD_PRIORITY_LOWEST, // 1 MinPriority
3413 THREAD_PRIORITY_LOWEST, // 2
3414 THREAD_PRIORITY_BELOW_NORMAL, // 3
3415 THREAD_PRIORITY_BELOW_NORMAL, // 4
3416 THREAD_PRIORITY_NORMAL, // 5 NormPriority
3417 THREAD_PRIORITY_ABOVE_NORMAL, // 6
3418 THREAD_PRIORITY_ABOVE_NORMAL, // 7
3419 THREAD_PRIORITY_HIGHEST, // 8
3420 THREAD_PRIORITY_HIGHEST, // 9 NearMaxPriority
3421 THREAD_PRIORITY_TIME_CRITICAL, // 10 MaxPriority
3422 THREAD_PRIORITY_TIME_CRITICAL // 11 CriticalPriority
3423 };
3424
3425 static int prio_init() {
3426 // If ThreadPriorityPolicy is 1, switch tables
3427 if (ThreadPriorityPolicy == 1) {
3428 int i;
3429 for (i = 0; i < CriticalPriority + 1; i++) {
3430 os::java_to_os_priority[i] = prio_policy1[i];
3431 }
3432 }
3433 if (UseCriticalJavaThreadPriority) {
3434 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
3435 }
3436 return 0;
3437 }
3438
3439 OSReturn os::set_native_priority(Thread* thread, int priority) {
3440 if (!UseThreadPriorities) return OS_OK;
3441 bool ret = SetThreadPriority(thread->osthread()->thread_handle(), priority) != 0;
3442 return ret ? OS_OK : OS_ERR;
3443 }
3444
3445 OSReturn os::get_native_priority(const Thread* const thread,
3446 int* priority_ptr) {
3447 if (!UseThreadPriorities) {
3448 *priority_ptr = java_to_os_priority[NormPriority];
3449 return OS_OK;
3450 }
3451 int os_prio = GetThreadPriority(thread->osthread()->thread_handle());
3452 if (os_prio == THREAD_PRIORITY_ERROR_RETURN) {
3453 assert(false, "GetThreadPriority failed");
3454 return OS_ERR;
3455 }
3456 *priority_ptr = os_prio;
3457 return OS_OK;
3458 }
3459
3460
3461 // Hint to the underlying OS that a task switch would not be good.
3462 // Void return because it's a hint and can fail.
3463 void os::hint_no_preempt() {}
3464
3465 void os::interrupt(Thread* thread) {
3466 assert(!thread->is_Java_thread() || Thread::current() == thread ||
3467 Threads_lock->owned_by_self(),
3468 "possibility of dangling Thread pointer");
3469
3470 OSThread* osthread = thread->osthread();
3471 osthread->set_interrupted(true);
3472 // More than one thread can get here with the same value of osthread,
3473 // resulting in multiple notifications. We do, however, want the store
3474 // to interrupted() to be visible to other threads before we post
3475 // the interrupt event.
3476 OrderAccess::release();
3477 SetEvent(osthread->interrupt_event());
3478 // For JSR166: unpark after setting status
3479 if (thread->is_Java_thread()) {
3480 ((JavaThread*)thread)->parker()->unpark();
3481 }
3482
3483 ParkEvent * ev = thread->_ParkEvent;
3484 if (ev != NULL) ev->unpark();
3485 }
3486
3487
3488 bool os::is_interrupted(Thread* thread, bool clear_interrupted) {
3489 assert(!thread->is_Java_thread() || Thread::current() == thread || Threads_lock->owned_by_self(),
3490 "possibility of dangling Thread pointer");
3491
3492 OSThread* osthread = thread->osthread();
3493 // There is no synchronization between the setting of the interrupt
3494 // and it being cleared here. It is critical - see 6535709 - that
3495 // we only clear the interrupt state, and reset the interrupt event,
3496 // if we are going to report that we were indeed interrupted - else
3497 // an interrupt can be "lost", leading to spurious wakeups or lost wakeups
3498 // depending on the timing. By checking thread interrupt event to see
3499 // if the thread gets real interrupt thus prevent spurious wakeup.
3500 bool interrupted = osthread->interrupted() && (WaitForSingleObject(osthread->interrupt_event(), 0) == WAIT_OBJECT_0);
3501 if (interrupted && clear_interrupted) {
3502 osthread->set_interrupted(false);
3503 ResetEvent(osthread->interrupt_event());
3504 } // Otherwise leave the interrupted state alone
3505
3506 return interrupted;
3507 }
3508
3509 // GetCurrentThreadId() returns DWORD
3510 intx os::current_thread_id() { return GetCurrentThreadId(); }
3511
3512 static int _initial_pid = 0;
3513
3514 int os::current_process_id() {
3515 return (_initial_pid ? _initial_pid : _getpid());
3516 }
3517
3518 int os::win32::_vm_page_size = 0;
3519 int os::win32::_vm_allocation_granularity = 0;
3520 int os::win32::_processor_type = 0;
3521 // Processor level is not available on non-NT systems, use vm_version instead
3522 int os::win32::_processor_level = 0;
3523 julong os::win32::_physical_memory = 0;
3524 size_t os::win32::_default_stack_size = 0;
3525
3526 intx os::win32::_os_thread_limit = 0;
3527 volatile intx os::win32::_os_thread_count = 0;
3528
3529 bool os::win32::_is_windows_server = false;
3530
3531 // 6573254
3532 // Currently, the bug is observed across all the supported Windows releases,
3533 // including the latest one (as of this writing - Windows Server 2012 R2)
3534 bool os::win32::_has_exit_bug = true;
3535
3536 void os::win32::initialize_system_info() {
3537 SYSTEM_INFO si;
3538 GetSystemInfo(&si);
3539 _vm_page_size = si.dwPageSize;
3540 _vm_allocation_granularity = si.dwAllocationGranularity;
3541 _processor_type = si.dwProcessorType;
3542 _processor_level = si.wProcessorLevel;
3543 set_processor_count(si.dwNumberOfProcessors);
3544
3545 MEMORYSTATUSEX ms;
3546 ms.dwLength = sizeof(ms);
3547
3548 // also returns dwAvailPhys (free physical memory bytes), dwTotalVirtual, dwAvailVirtual,
3549 // dwMemoryLoad (% of memory in use)
3550 GlobalMemoryStatusEx(&ms);
3551 _physical_memory = ms.ullTotalPhys;
3552
3553 if (FLAG_IS_DEFAULT(MaxRAM)) {
3554 // Adjust MaxRAM according to the maximum virtual address space available.
3555 FLAG_SET_DEFAULT(MaxRAM, MIN2(MaxRAM, (uint64_t) ms.ullTotalVirtual));
3556 }
3557
3558 OSVERSIONINFOEX oi;
3559 oi.dwOSVersionInfoSize = sizeof(OSVERSIONINFOEX);
3560 GetVersionEx((OSVERSIONINFO*)&oi);
3561 switch (oi.dwPlatformId) {
3562 case VER_PLATFORM_WIN32_NT:
3563 {
3564 int os_vers = oi.dwMajorVersion * 1000 + oi.dwMinorVersion;
3565 if (oi.wProductType == VER_NT_DOMAIN_CONTROLLER ||
3566 oi.wProductType == VER_NT_SERVER) {
3567 _is_windows_server = true;
3568 }
3569 }
3570 break;
3571 default: fatal("Unknown platform");
3572 }
3573
3574 _default_stack_size = os::current_stack_size();
3575 assert(_default_stack_size > (size_t) _vm_page_size, "invalid stack size");
3576 assert((_default_stack_size & (_vm_page_size - 1)) == 0,
3577 "stack size not a multiple of page size");
3578
3579 initialize_performance_counter();
3580 }
3581
3582
3583 HINSTANCE os::win32::load_Windows_dll(const char* name, char *ebuf,
3584 int ebuflen) {
3585 char path[MAX_PATH];
3586 DWORD size;
3587 DWORD pathLen = (DWORD)sizeof(path);
3588 HINSTANCE result = NULL;
3589
3590 // only allow library name without path component
3591 assert(strchr(name, '\\') == NULL, "path not allowed");
3592 assert(strchr(name, ':') == NULL, "path not allowed");
3593 if (strchr(name, '\\') != NULL || strchr(name, ':') != NULL) {
3594 jio_snprintf(ebuf, ebuflen,
3595 "Invalid parameter while calling os::win32::load_windows_dll(): cannot take path: %s", name);
3596 return NULL;
3597 }
3598
3599 // search system directory
3600 if ((size = GetSystemDirectory(path, pathLen)) > 0) {
3601 if (size >= pathLen) {
3602 return NULL; // truncated
3603 }
3604 if (jio_snprintf(path + size, pathLen - size, "\\%s", name) == -1) {
3605 return NULL; // truncated
3606 }
3607 if ((result = (HINSTANCE)os::dll_load(path, ebuf, ebuflen)) != NULL) {
3608 return result;
3609 }
3610 }
3611
3612 // try Windows directory
3613 if ((size = GetWindowsDirectory(path, pathLen)) > 0) {
3614 if (size >= pathLen) {
3615 return NULL; // truncated
3616 }
3617 if (jio_snprintf(path + size, pathLen - size, "\\%s", name) == -1) {
3618 return NULL; // truncated
3619 }
3620 if ((result = (HINSTANCE)os::dll_load(path, ebuf, ebuflen)) != NULL) {
3621 return result;
3622 }
3623 }
3624
3625 jio_snprintf(ebuf, ebuflen,
3626 "os::win32::load_windows_dll() cannot load %s from system directories.", name);
3627 return NULL;
3628 }
3629
3630 #define MAXIMUM_THREADS_TO_KEEP (16 * MAXIMUM_WAIT_OBJECTS)
3631 #define EXIT_TIMEOUT 300000 /* 5 minutes */
3632
3633 static BOOL CALLBACK init_crit_sect_call(PINIT_ONCE, PVOID pcrit_sect, PVOID*) {
3634 InitializeCriticalSection((CRITICAL_SECTION*)pcrit_sect);
3635 return TRUE;
3636 }
3637
3638 int os::win32::exit_process_or_thread(Ept what, int exit_code) {
3639 // Basic approach:
3640 // - Each exiting thread registers its intent to exit and then does so.
3641 // - A thread trying to terminate the process must wait for all
3642 // threads currently exiting to complete their exit.
3643
3644 if (os::win32::has_exit_bug()) {
3645 // The array holds handles of the threads that have started exiting by calling
3646 // _endthreadex().
3647 // Should be large enough to avoid blocking the exiting thread due to lack of
3648 // a free slot.
3649 static HANDLE handles[MAXIMUM_THREADS_TO_KEEP];
3650 static int handle_count = 0;
3651
3652 static INIT_ONCE init_once_crit_sect = INIT_ONCE_STATIC_INIT;
3653 static CRITICAL_SECTION crit_sect;
3654 static volatile jint process_exiting = 0;
3655 int i, j;
3656 DWORD res;
3657 HANDLE hproc, hthr;
3658
3659 // We only attempt to register threads until a process exiting
3660 // thread manages to set the process_exiting flag. Any threads
3661 // that come through here after the process_exiting flag is set
3662 // are unregistered and will be caught in the SuspendThread()
3663 // infinite loop below.
3664 bool registered = false;
3665
3666 // The first thread that reached this point, initializes the critical section.
3667 if (!InitOnceExecuteOnce(&init_once_crit_sect, init_crit_sect_call, &crit_sect, NULL)) {
3668 warning("crit_sect initialization failed in %s: %d\n", __FILE__, __LINE__);
3669 } else if (OrderAccess::load_acquire(&process_exiting) == 0) {
3670 if (what != EPT_THREAD) {
3671 // Atomically set process_exiting before the critical section
3672 // to increase the visibility between racing threads.
3673 Atomic::cmpxchg((jint)GetCurrentThreadId(), &process_exiting, 0);
3674 }
3675 EnterCriticalSection(&crit_sect);
3676
3677 if (what == EPT_THREAD && OrderAccess::load_acquire(&process_exiting) == 0) {
3678 // Remove from the array those handles of the threads that have completed exiting.
3679 for (i = 0, j = 0; i < handle_count; ++i) {
3680 res = WaitForSingleObject(handles[i], 0 /* don't wait */);
3681 if (res == WAIT_TIMEOUT) {
3682 handles[j++] = handles[i];
3683 } else {
3684 if (res == WAIT_FAILED) {
3685 warning("WaitForSingleObject failed (%u) in %s: %d\n",
3686 GetLastError(), __FILE__, __LINE__);
3687 }
3688 // Don't keep the handle, if we failed waiting for it.
3689 CloseHandle(handles[i]);
3690 }
3691 }
3692
3693 // If there's no free slot in the array of the kept handles, we'll have to
3694 // wait until at least one thread completes exiting.
3695 if ((handle_count = j) == MAXIMUM_THREADS_TO_KEEP) {
3696 // Raise the priority of the oldest exiting thread to increase its chances
3697 // to complete sooner.
3698 SetThreadPriority(handles[0], THREAD_PRIORITY_ABOVE_NORMAL);
3699 res = WaitForMultipleObjects(MAXIMUM_WAIT_OBJECTS, handles, FALSE, EXIT_TIMEOUT);
3700 if (res >= WAIT_OBJECT_0 && res < (WAIT_OBJECT_0 + MAXIMUM_WAIT_OBJECTS)) {
3701 i = (res - WAIT_OBJECT_0);
3702 handle_count = MAXIMUM_THREADS_TO_KEEP - 1;
3703 for (; i < handle_count; ++i) {
3704 handles[i] = handles[i + 1];
3705 }
3706 } else {
3707 warning("WaitForMultipleObjects %s (%u) in %s: %d\n",
3708 (res == WAIT_FAILED ? "failed" : "timed out"),
3709 GetLastError(), __FILE__, __LINE__);
3710 // Don't keep handles, if we failed waiting for them.
3711 for (i = 0; i < MAXIMUM_THREADS_TO_KEEP; ++i) {
3712 CloseHandle(handles[i]);
3713 }
3714 handle_count = 0;
3715 }
3716 }
3717
3718 // Store a duplicate of the current thread handle in the array of handles.
3719 hproc = GetCurrentProcess();
3720 hthr = GetCurrentThread();
3721 if (!DuplicateHandle(hproc, hthr, hproc, &handles[handle_count],
3722 0, FALSE, DUPLICATE_SAME_ACCESS)) {
3723 warning("DuplicateHandle failed (%u) in %s: %d\n",
3724 GetLastError(), __FILE__, __LINE__);
3725
3726 // We can't register this thread (no more handles) so this thread
3727 // may be racing with a thread that is calling exit(). If the thread
3728 // that is calling exit() has managed to set the process_exiting
3729 // flag, then this thread will be caught in the SuspendThread()
3730 // infinite loop below which closes that race. A small timing
3731 // window remains before the process_exiting flag is set, but it
3732 // is only exposed when we are out of handles.
3733 } else {
3734 ++handle_count;
3735 registered = true;
3736
3737 // The current exiting thread has stored its handle in the array, and now
3738 // should leave the critical section before calling _endthreadex().
3739 }
3740
3741 } else if (what != EPT_THREAD && handle_count > 0) {
3742 jlong start_time, finish_time, timeout_left;
3743 // Before ending the process, make sure all the threads that had called
3744 // _endthreadex() completed.
3745
3746 // Set the priority level of the current thread to the same value as
3747 // the priority level of exiting threads.
3748 // This is to ensure it will be given a fair chance to execute if
3749 // the timeout expires.
3750 hthr = GetCurrentThread();
3751 SetThreadPriority(hthr, THREAD_PRIORITY_ABOVE_NORMAL);
3752 start_time = os::javaTimeNanos();
3753 finish_time = start_time + ((jlong)EXIT_TIMEOUT * 1000000L);
3754 for (i = 0; ; ) {
3755 int portion_count = handle_count - i;
3756 if (portion_count > MAXIMUM_WAIT_OBJECTS) {
3757 portion_count = MAXIMUM_WAIT_OBJECTS;
3758 }
3759 for (j = 0; j < portion_count; ++j) {
3760 SetThreadPriority(handles[i + j], THREAD_PRIORITY_ABOVE_NORMAL);
3761 }
3762 timeout_left = (finish_time - start_time) / 1000000L;
3763 if (timeout_left < 0) {
3764 timeout_left = 0;
3765 }
3766 res = WaitForMultipleObjects(portion_count, handles + i, TRUE, timeout_left);
3767 if (res == WAIT_FAILED || res == WAIT_TIMEOUT) {
3768 warning("WaitForMultipleObjects %s (%u) in %s: %d\n",
3769 (res == WAIT_FAILED ? "failed" : "timed out"),
3770 GetLastError(), __FILE__, __LINE__);
3771 // Reset portion_count so we close the remaining
3772 // handles due to this error.
3773 portion_count = handle_count - i;
3774 }
3775 for (j = 0; j < portion_count; ++j) {
3776 CloseHandle(handles[i + j]);
3777 }
3778 if ((i += portion_count) >= handle_count) {
3779 break;
3780 }
3781 start_time = os::javaTimeNanos();
3782 }
3783 handle_count = 0;
3784 }
3785
3786 LeaveCriticalSection(&crit_sect);
3787 }
3788
3789 if (!registered &&
3790 OrderAccess::load_acquire(&process_exiting) != 0 &&
3791 process_exiting != (jint)GetCurrentThreadId()) {
3792 // Some other thread is about to call exit(), so we don't let
3793 // the current unregistered thread proceed to exit() or _endthreadex()
3794 while (true) {
3795 SuspendThread(GetCurrentThread());
3796 // Avoid busy-wait loop, if SuspendThread() failed.
3797 Sleep(EXIT_TIMEOUT);
3798 }
3799 }
3800 }
3801
3802 // We are here if either
3803 // - there's no 'race at exit' bug on this OS release;
3804 // - initialization of the critical section failed (unlikely);
3805 // - the current thread has registered itself and left the critical section;
3806 // - the process-exiting thread has raised the flag and left the critical section.
3807 if (what == EPT_THREAD) {
3808 _endthreadex((unsigned)exit_code);
3809 } else if (what == EPT_PROCESS) {
3810 ::exit(exit_code);
3811 } else {
3812 _exit(exit_code);
3813 }
3814
3815 // Should not reach here
3816 return exit_code;
3817 }
3818
3819 #undef EXIT_TIMEOUT
3820
3821 void os::win32::setmode_streams() {
3822 _setmode(_fileno(stdin), _O_BINARY);
3823 _setmode(_fileno(stdout), _O_BINARY);
3824 _setmode(_fileno(stderr), _O_BINARY);
3825 }
3826
3827
3828 bool os::is_debugger_attached() {
3829 return IsDebuggerPresent() ? true : false;
3830 }
3831
3832
3833 void os::wait_for_keypress_at_exit(void) {
3834 if (PauseAtExit) {
3835 fprintf(stderr, "Press any key to continue...\n");
3836 fgetc(stdin);
3837 }
3838 }
3839
3840
3841 bool os::message_box(const char* title, const char* message) {
3842 int result = MessageBox(NULL, message, title,
3843 MB_YESNO | MB_ICONERROR | MB_SYSTEMMODAL | MB_DEFAULT_DESKTOP_ONLY);
3844 return result == IDYES;
3845 }
3846
3847 #ifndef PRODUCT
3848 #ifndef _WIN64
3849 // Helpers to check whether NX protection is enabled
3850 int nx_exception_filter(_EXCEPTION_POINTERS *pex) {
3851 if (pex->ExceptionRecord->ExceptionCode == EXCEPTION_ACCESS_VIOLATION &&
3852 pex->ExceptionRecord->NumberParameters > 0 &&
3853 pex->ExceptionRecord->ExceptionInformation[0] ==
3854 EXCEPTION_INFO_EXEC_VIOLATION) {
3855 return EXCEPTION_EXECUTE_HANDLER;
3856 }
3857 return EXCEPTION_CONTINUE_SEARCH;
3858 }
3859
3860 void nx_check_protection() {
3861 // If NX is enabled we'll get an exception calling into code on the stack
3862 char code[] = { (char)0xC3 }; // ret
3863 void *code_ptr = (void *)code;
3864 __try {
3865 __asm call code_ptr
3866 } __except(nx_exception_filter((_EXCEPTION_POINTERS*)_exception_info())) {
3867 tty->print_raw_cr("NX protection detected.");
3868 }
3869 }
3870 #endif // _WIN64
3871 #endif // PRODUCT
3872
3873 // This is called _before_ the global arguments have been parsed
3874 void os::init(void) {
3875 _initial_pid = _getpid();
3876
3877 init_random(1234567);
3878
3879 win32::initialize_system_info();
3880 win32::setmode_streams();
3881 init_page_sizes((size_t) win32::vm_page_size());
3882
3883 // This may be overridden later when argument processing is done.
3884 FLAG_SET_ERGO(bool, UseLargePagesIndividualAllocation, false);
3885
3886 // Initialize main_process and main_thread
3887 main_process = GetCurrentProcess(); // Remember main_process is a pseudo handle
3888 if (!DuplicateHandle(main_process, GetCurrentThread(), main_process,
3889 &main_thread, THREAD_ALL_ACCESS, false, 0)) {
3890 fatal("DuplicateHandle failed\n");
3891 }
3892 main_thread_id = (int) GetCurrentThreadId();
3893
3894 // initialize fast thread access - only used for 32-bit
3895 win32::initialize_thread_ptr_offset();
3896 }
3897
3898 // To install functions for atexit processing
3899 extern "C" {
3900 static void perfMemory_exit_helper() {
3901 perfMemory_exit();
3902 }
3903 }
3904
3905 static jint initSock();
3906
3907 // this is called _after_ the global arguments have been parsed
3908 jint os::init_2(void) {
3909 // Allocate a single page and mark it as readable for safepoint polling
3910 address polling_page = (address)VirtualAlloc(NULL, os::vm_page_size(), MEM_RESERVE, PAGE_READONLY);
3911 guarantee(polling_page != NULL, "Reserve Failed for polling page");
3912
3913 address return_page = (address)VirtualAlloc(polling_page, os::vm_page_size(), MEM_COMMIT, PAGE_READONLY);
3914 guarantee(return_page != NULL, "Commit Failed for polling page");
3915
3916 os::set_polling_page(polling_page);
3917 log_info(os)("SafePoint Polling address: " INTPTR_FORMAT, p2i(polling_page));
3918
3919 if (!UseMembar) {
3920 address mem_serialize_page = (address)VirtualAlloc(NULL, os::vm_page_size(), MEM_RESERVE, PAGE_READWRITE);
3921 guarantee(mem_serialize_page != NULL, "Reserve Failed for memory serialize page");
3922
3923 return_page = (address)VirtualAlloc(mem_serialize_page, os::vm_page_size(), MEM_COMMIT, PAGE_READWRITE);
3924 guarantee(return_page != NULL, "Commit Failed for memory serialize page");
3925
3926 os::set_memory_serialize_page(mem_serialize_page);
3927 log_info(os)("Memory Serialize Page address: " INTPTR_FORMAT, p2i(mem_serialize_page));
3928 }
3929
3930 // Setup Windows Exceptions
3931
3932 // for debugging float code generation bugs
3933 if (ForceFloatExceptions) {
3934 #ifndef _WIN64
3935 static long fp_control_word = 0;
3936 __asm { fstcw fp_control_word }
3937 // see Intel PPro Manual, Vol. 2, p 7-16
3938 const long precision = 0x20;
3939 const long underflow = 0x10;
3940 const long overflow = 0x08;
3941 const long zero_div = 0x04;
3942 const long denorm = 0x02;
3943 const long invalid = 0x01;
3944 fp_control_word |= invalid;
3945 __asm { fldcw fp_control_word }
3946 #endif
3947 }
3948
3949 // If stack_commit_size is 0, windows will reserve the default size,
3950 // but only commit a small portion of it.
3951 size_t stack_commit_size = align_up(ThreadStackSize*K, os::vm_page_size());
3952 size_t default_reserve_size = os::win32::default_stack_size();
3953 size_t actual_reserve_size = stack_commit_size;
3954 if (stack_commit_size < default_reserve_size) {
3955 // If stack_commit_size == 0, we want this too
3956 actual_reserve_size = default_reserve_size;
3957 }
3958
3959 // Check minimum allowable stack size for thread creation and to initialize
3960 // the java system classes, including StackOverflowError - depends on page
3961 // size. Add two 4K pages for compiler2 recursion in main thread.
3962 // Add in 4*BytesPerWord 4K pages to account for VM stack during
3963 // class initialization depending on 32 or 64 bit VM.
3964 size_t min_stack_allowed =
3965 (size_t)(JavaThread::stack_guard_zone_size() +
3966 JavaThread::stack_shadow_zone_size() +
3967 (4*BytesPerWord COMPILER2_PRESENT(+2)) * 4 * K);
3968
3969 min_stack_allowed = align_up(min_stack_allowed, os::vm_page_size());
3970
3971 if (actual_reserve_size < min_stack_allowed) {
3972 tty->print_cr("\nThe Java thread stack size specified is too small. "
3973 "Specify at least %dk",
3974 min_stack_allowed / K);
3975 return JNI_ERR;
3976 }
3977
3978 JavaThread::set_stack_size_at_create(stack_commit_size);
3979
3980 // Calculate theoretical max. size of Threads to guard gainst artifical
3981 // out-of-memory situations, where all available address-space has been
3982 // reserved by thread stacks.
3983 assert(actual_reserve_size != 0, "Must have a stack");
3984
3985 // Calculate the thread limit when we should start doing Virtual Memory
3986 // banging. Currently when the threads will have used all but 200Mb of space.
3987 //
3988 // TODO: consider performing a similar calculation for commit size instead
3989 // as reserve size, since on a 64-bit platform we'll run into that more
3990 // often than running out of virtual memory space. We can use the
3991 // lower value of the two calculations as the os_thread_limit.
3992 size_t max_address_space = ((size_t)1 << (BitsPerWord - 1)) - (200 * K * K);
3993 win32::_os_thread_limit = (intx)(max_address_space / actual_reserve_size);
3994
3995 // at exit methods are called in the reverse order of their registration.
3996 // there is no limit to the number of functions registered. atexit does
3997 // not set errno.
3998
3999 if (PerfAllowAtExitRegistration) {
4000 // only register atexit functions if PerfAllowAtExitRegistration is set.
4001 // atexit functions can be delayed until process exit time, which
4002 // can be problematic for embedded VM situations. Embedded VMs should
4003 // call DestroyJavaVM() to assure that VM resources are released.
4004
4005 // note: perfMemory_exit_helper atexit function may be removed in
4006 // the future if the appropriate cleanup code can be added to the
4007 // VM_Exit VMOperation's doit method.
4008 if (atexit(perfMemory_exit_helper) != 0) {
4009 warning("os::init_2 atexit(perfMemory_exit_helper) failed");
4010 }
4011 }
4012
4013 #ifndef _WIN64
4014 // Print something if NX is enabled (win32 on AMD64)
4015 NOT_PRODUCT(if (PrintMiscellaneous && Verbose) nx_check_protection());
4016 #endif
4017
4018 // initialize thread priority policy
4019 prio_init();
4020
4021 if (UseNUMA && !ForceNUMA) {
4022 UseNUMA = false; // We don't fully support this yet
4023 }
4024
4025 if (UseNUMAInterleaving) {
4026 // first check whether this Windows OS supports VirtualAllocExNuma, if not ignore this flag
4027 bool success = numa_interleaving_init();
4028 if (!success) UseNUMAInterleaving = false;
4029 }
4030
4031 if (initSock() != JNI_OK) {
4032 return JNI_ERR;
4033 }
4034
4035 return JNI_OK;
4036 }
4037
4038 // Mark the polling page as unreadable
4039 void os::make_polling_page_unreadable(void) {
4040 DWORD old_status;
4041 if (!VirtualProtect((char *)_polling_page, os::vm_page_size(),
4042 PAGE_NOACCESS, &old_status)) {
4043 fatal("Could not disable polling page");
4044 }
4045 }
4046
4047 // Mark the polling page as readable
4048 void os::make_polling_page_readable(void) {
4049 DWORD old_status;
4050 if (!VirtualProtect((char *)_polling_page, os::vm_page_size(),
4051 PAGE_READONLY, &old_status)) {
4052 fatal("Could not enable polling page");
4053 }
4054 }
4055
4056
4057 int os::stat(const char *path, struct stat *sbuf) {
4058 char pathbuf[MAX_PATH];
4059 if (strlen(path) > MAX_PATH - 1) {
4060 errno = ENAMETOOLONG;
4061 return -1;
4062 }
4063 os::native_path(strcpy(pathbuf, path));
4064 int ret = ::stat(pathbuf, sbuf);
4065 if (sbuf != NULL && UseUTCFileTimestamp) {
4066 // Fix for 6539723. st_mtime returned from stat() is dependent on
4067 // the system timezone and so can return different values for the
4068 // same file if/when daylight savings time changes. This adjustment
4069 // makes sure the same timestamp is returned regardless of the TZ.
4070 //
4071 // See:
4072 // http://msdn.microsoft.com/library/
4073 // default.asp?url=/library/en-us/sysinfo/base/
4074 // time_zone_information_str.asp
4075 // and
4076 // http://msdn.microsoft.com/library/default.asp?url=
4077 // /library/en-us/sysinfo/base/settimezoneinformation.asp
4078 //
4079 // NOTE: there is a insidious bug here: If the timezone is changed
4080 // after the call to stat() but before 'GetTimeZoneInformation()', then
4081 // the adjustment we do here will be wrong and we'll return the wrong
4082 // value (which will likely end up creating an invalid class data
4083 // archive). Absent a better API for this, or some time zone locking
4084 // mechanism, we'll have to live with this risk.
4085 TIME_ZONE_INFORMATION tz;
4086 DWORD tzid = GetTimeZoneInformation(&tz);
4087 int daylightBias =
4088 (tzid == TIME_ZONE_ID_DAYLIGHT) ? tz.DaylightBias : tz.StandardBias;
4089 sbuf->st_mtime += (tz.Bias + daylightBias) * 60;
4090 }
4091 return ret;
4092 }
4093
4094
4095 #define FT2INT64(ft) \
4096 ((jlong)((jlong)(ft).dwHighDateTime << 32 | (julong)(ft).dwLowDateTime))
4097
4098
4099 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
4100 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
4101 // of a thread.
4102 //
4103 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
4104 // the fast estimate available on the platform.
4105
4106 // current_thread_cpu_time() is not optimized for Windows yet
4107 jlong os::current_thread_cpu_time() {
4108 // return user + sys since the cost is the same
4109 return os::thread_cpu_time(Thread::current(), true /* user+sys */);
4110 }
4111
4112 jlong os::thread_cpu_time(Thread* thread) {
4113 // consistent with what current_thread_cpu_time() returns.
4114 return os::thread_cpu_time(thread, true /* user+sys */);
4115 }
4116
4117 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
4118 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
4119 }
4120
4121 jlong os::thread_cpu_time(Thread* thread, bool user_sys_cpu_time) {
4122 // This code is copy from clasic VM -> hpi::sysThreadCPUTime
4123 // If this function changes, os::is_thread_cpu_time_supported() should too
4124 FILETIME CreationTime;
4125 FILETIME ExitTime;
4126 FILETIME KernelTime;
4127 FILETIME UserTime;
4128
4129 if (GetThreadTimes(thread->osthread()->thread_handle(), &CreationTime,
4130 &ExitTime, &KernelTime, &UserTime) == 0) {
4131 return -1;
4132 } else if (user_sys_cpu_time) {
4133 return (FT2INT64(UserTime) + FT2INT64(KernelTime)) * 100;
4134 } else {
4135 return FT2INT64(UserTime) * 100;
4136 }
4137 }
4138
4139 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4140 info_ptr->max_value = ALL_64_BITS; // the max value -- all 64 bits
4141 info_ptr->may_skip_backward = false; // GetThreadTimes returns absolute time
4142 info_ptr->may_skip_forward = false; // GetThreadTimes returns absolute time
4143 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4144 }
4145
4146 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4147 info_ptr->max_value = ALL_64_BITS; // the max value -- all 64 bits
4148 info_ptr->may_skip_backward = false; // GetThreadTimes returns absolute time
4149 info_ptr->may_skip_forward = false; // GetThreadTimes returns absolute time
4150 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4151 }
4152
4153 bool os::is_thread_cpu_time_supported() {
4154 // see os::thread_cpu_time
4155 FILETIME CreationTime;
4156 FILETIME ExitTime;
4157 FILETIME KernelTime;
4158 FILETIME UserTime;
4159
4160 if (GetThreadTimes(GetCurrentThread(), &CreationTime, &ExitTime,
4161 &KernelTime, &UserTime) == 0) {
4162 return false;
4163 } else {
4164 return true;
4165 }
4166 }
4167
4168 // Windows does't provide a loadavg primitive so this is stubbed out for now.
4169 // It does have primitives (PDH API) to get CPU usage and run queue length.
4170 // "\\Processor(_Total)\\% Processor Time", "\\System\\Processor Queue Length"
4171 // If we wanted to implement loadavg on Windows, we have a few options:
4172 //
4173 // a) Query CPU usage and run queue length and "fake" an answer by
4174 // returning the CPU usage if it's under 100%, and the run queue
4175 // length otherwise. It turns out that querying is pretty slow
4176 // on Windows, on the order of 200 microseconds on a fast machine.
4177 // Note that on the Windows the CPU usage value is the % usage
4178 // since the last time the API was called (and the first call
4179 // returns 100%), so we'd have to deal with that as well.
4180 //
4181 // b) Sample the "fake" answer using a sampling thread and store
4182 // the answer in a global variable. The call to loadavg would
4183 // just return the value of the global, avoiding the slow query.
4184 //
4185 // c) Sample a better answer using exponential decay to smooth the
4186 // value. This is basically the algorithm used by UNIX kernels.
4187 //
4188 // Note that sampling thread starvation could affect both (b) and (c).
4189 int os::loadavg(double loadavg[], int nelem) {
4190 return -1;
4191 }
4192
4193
4194 // DontYieldALot=false by default: dutifully perform all yields as requested by JVM_Yield()
4195 bool os::dont_yield() {
4196 return DontYieldALot;
4197 }
4198
4199 // This method is a slightly reworked copy of JDK's sysOpen
4200 // from src/windows/hpi/src/sys_api_md.c
4201
4202 int os::open(const char *path, int oflag, int mode) {
4203 char pathbuf[MAX_PATH];
4204
4205 if (strlen(path) > MAX_PATH - 1) {
4206 errno = ENAMETOOLONG;
4207 return -1;
4208 }
4209 os::native_path(strcpy(pathbuf, path));
4210 return ::open(pathbuf, oflag | O_BINARY | O_NOINHERIT, mode);
4211 }
4212
4213 FILE* os::open(int fd, const char* mode) {
4214 return ::_fdopen(fd, mode);
4215 }
4216
4217 // Is a (classpath) directory empty?
4218 bool os::dir_is_empty(const char* path) {
4219 WIN32_FIND_DATA fd;
4220 HANDLE f = FindFirstFile(path, &fd);
4221 if (f == INVALID_HANDLE_VALUE) {
4222 return true;
4223 }
4224 FindClose(f);
4225 return false;
4226 }
4227
4228 // create binary file, rewriting existing file if required
4229 int os::create_binary_file(const char* path, bool rewrite_existing) {
4230 int oflags = _O_CREAT | _O_WRONLY | _O_BINARY;
4231 if (!rewrite_existing) {
4232 oflags |= _O_EXCL;
4233 }
4234 return ::open(path, oflags, _S_IREAD | _S_IWRITE);
4235 }
4236
4237 // return current position of file pointer
4238 jlong os::current_file_offset(int fd) {
4239 return (jlong)::_lseeki64(fd, (__int64)0L, SEEK_CUR);
4240 }
4241
4242 // move file pointer to the specified offset
4243 jlong os::seek_to_file_offset(int fd, jlong offset) {
4244 return (jlong)::_lseeki64(fd, (__int64)offset, SEEK_SET);
4245 }
4246
4247
4248 jlong os::lseek(int fd, jlong offset, int whence) {
4249 return (jlong) ::_lseeki64(fd, offset, whence);
4250 }
4251
4252 size_t os::read_at(int fd, void *buf, unsigned int nBytes, jlong offset) {
4253 OVERLAPPED ov;
4254 DWORD nread;
4255 BOOL result;
4256
4257 ZeroMemory(&ov, sizeof(ov));
4258 ov.Offset = (DWORD)offset;
4259 ov.OffsetHigh = (DWORD)(offset >> 32);
4260
4261 HANDLE h = (HANDLE)::_get_osfhandle(fd);
4262
4263 result = ReadFile(h, (LPVOID)buf, nBytes, &nread, &ov);
4264
4265 return result ? nread : 0;
4266 }
4267
4268
4269 // This method is a slightly reworked copy of JDK's sysNativePath
4270 // from src/windows/hpi/src/path_md.c
4271
4272 // Convert a pathname to native format. On win32, this involves forcing all
4273 // separators to be '\\' rather than '/' (both are legal inputs, but Win95
4274 // sometimes rejects '/') and removing redundant separators. The input path is
4275 // assumed to have been converted into the character encoding used by the local
4276 // system. Because this might be a double-byte encoding, care is taken to
4277 // treat double-byte lead characters correctly.
4278 //
4279 // This procedure modifies the given path in place, as the result is never
4280 // longer than the original. There is no error return; this operation always
4281 // succeeds.
4282 char * os::native_path(char *path) {
4283 char *src = path, *dst = path, *end = path;
4284 char *colon = NULL; // If a drive specifier is found, this will
4285 // point to the colon following the drive letter
4286
4287 // Assumption: '/', '\\', ':', and drive letters are never lead bytes
4288 assert(((!::IsDBCSLeadByte('/')) && (!::IsDBCSLeadByte('\\'))
4289 && (!::IsDBCSLeadByte(':'))), "Illegal lead byte");
4290
4291 // Check for leading separators
4292 #define isfilesep(c) ((c) == '/' || (c) == '\\')
4293 while (isfilesep(*src)) {
4294 src++;
4295 }
4296
4297 if (::isalpha(*src) && !::IsDBCSLeadByte(*src) && src[1] == ':') {
4298 // Remove leading separators if followed by drive specifier. This
4299 // hack is necessary to support file URLs containing drive
4300 // specifiers (e.g., "file://c:/path"). As a side effect,
4301 // "/c:/path" can be used as an alternative to "c:/path".
4302 *dst++ = *src++;
4303 colon = dst;
4304 *dst++ = ':';
4305 src++;
4306 } else {
4307 src = path;
4308 if (isfilesep(src[0]) && isfilesep(src[1])) {
4309 // UNC pathname: Retain first separator; leave src pointed at
4310 // second separator so that further separators will be collapsed
4311 // into the second separator. The result will be a pathname
4312 // beginning with "\\\\" followed (most likely) by a host name.
4313 src = dst = path + 1;
4314 path[0] = '\\'; // Force first separator to '\\'
4315 }
4316 }
4317
4318 end = dst;
4319
4320 // Remove redundant separators from remainder of path, forcing all
4321 // separators to be '\\' rather than '/'. Also, single byte space
4322 // characters are removed from the end of the path because those
4323 // are not legal ending characters on this operating system.
4324 //
4325 while (*src != '\0') {
4326 if (isfilesep(*src)) {
4327 *dst++ = '\\'; src++;
4328 while (isfilesep(*src)) src++;
4329 if (*src == '\0') {
4330 // Check for trailing separator
4331 end = dst;
4332 if (colon == dst - 2) break; // "z:\\"
4333 if (dst == path + 1) break; // "\\"
4334 if (dst == path + 2 && isfilesep(path[0])) {
4335 // "\\\\" is not collapsed to "\\" because "\\\\" marks the
4336 // beginning of a UNC pathname. Even though it is not, by
4337 // itself, a valid UNC pathname, we leave it as is in order
4338 // to be consistent with the path canonicalizer as well
4339 // as the win32 APIs, which treat this case as an invalid
4340 // UNC pathname rather than as an alias for the root
4341 // directory of the current drive.
4342 break;
4343 }
4344 end = --dst; // Path does not denote a root directory, so
4345 // remove trailing separator
4346 break;
4347 }
4348 end = dst;
4349 } else {
4350 if (::IsDBCSLeadByte(*src)) { // Copy a double-byte character
4351 *dst++ = *src++;
4352 if (*src) *dst++ = *src++;
4353 end = dst;
4354 } else { // Copy a single-byte character
4355 char c = *src++;
4356 *dst++ = c;
4357 // Space is not a legal ending character
4358 if (c != ' ') end = dst;
4359 }
4360 }
4361 }
4362
4363 *end = '\0';
4364
4365 // For "z:", add "." to work around a bug in the C runtime library
4366 if (colon == dst - 1) {
4367 path[2] = '.';
4368 path[3] = '\0';
4369 }
4370
4371 return path;
4372 }
4373
4374 // This code is a copy of JDK's sysSetLength
4375 // from src/windows/hpi/src/sys_api_md.c
4376
4377 int os::ftruncate(int fd, jlong length) {
4378 HANDLE h = (HANDLE)::_get_osfhandle(fd);
4379 long high = (long)(length >> 32);
4380 DWORD ret;
4381
4382 if (h == (HANDLE)(-1)) {
4383 return -1;
4384 }
4385
4386 ret = ::SetFilePointer(h, (long)(length), &high, FILE_BEGIN);
4387 if ((ret == 0xFFFFFFFF) && (::GetLastError() != NO_ERROR)) {
4388 return -1;
4389 }
4390
4391 if (::SetEndOfFile(h) == FALSE) {
4392 return -1;
4393 }
4394
4395 return 0;
4396 }
4397
4398 int os::get_fileno(FILE* fp) {
4399 return _fileno(fp);
4400 }
4401
4402 // This code is a copy of JDK's sysSync
4403 // from src/windows/hpi/src/sys_api_md.c
4404 // except for the legacy workaround for a bug in Win 98
4405
4406 int os::fsync(int fd) {
4407 HANDLE handle = (HANDLE)::_get_osfhandle(fd);
4408
4409 if ((!::FlushFileBuffers(handle)) &&
4410 (GetLastError() != ERROR_ACCESS_DENIED)) {
4411 // from winerror.h
4412 return -1;
4413 }
4414 return 0;
4415 }
4416
4417 static int nonSeekAvailable(int, long *);
4418 static int stdinAvailable(int, long *);
4419
4420 #define S_ISCHR(mode) (((mode) & _S_IFCHR) == _S_IFCHR)
4421 #define S_ISFIFO(mode) (((mode) & _S_IFIFO) == _S_IFIFO)
4422
4423 // This code is a copy of JDK's sysAvailable
4424 // from src/windows/hpi/src/sys_api_md.c
4425
4426 int os::available(int fd, jlong *bytes) {
4427 jlong cur, end;
4428 struct _stati64 stbuf64;
4429
4430 if (::_fstati64(fd, &stbuf64) >= 0) {
4431 int mode = stbuf64.st_mode;
4432 if (S_ISCHR(mode) || S_ISFIFO(mode)) {
4433 int ret;
4434 long lpbytes;
4435 if (fd == 0) {
4436 ret = stdinAvailable(fd, &lpbytes);
4437 } else {
4438 ret = nonSeekAvailable(fd, &lpbytes);
4439 }
4440 (*bytes) = (jlong)(lpbytes);
4441 return ret;
4442 }
4443 if ((cur = ::_lseeki64(fd, 0L, SEEK_CUR)) == -1) {
4444 return FALSE;
4445 } else if ((end = ::_lseeki64(fd, 0L, SEEK_END)) == -1) {
4446 return FALSE;
4447 } else if (::_lseeki64(fd, cur, SEEK_SET) == -1) {
4448 return FALSE;
4449 }
4450 *bytes = end - cur;
4451 return TRUE;
4452 } else {
4453 return FALSE;
4454 }
4455 }
4456
4457 void os::flockfile(FILE* fp) {
4458 _lock_file(fp);
4459 }
4460
4461 void os::funlockfile(FILE* fp) {
4462 _unlock_file(fp);
4463 }
4464
4465 // This code is a copy of JDK's nonSeekAvailable
4466 // from src/windows/hpi/src/sys_api_md.c
4467
4468 static int nonSeekAvailable(int fd, long *pbytes) {
4469 // This is used for available on non-seekable devices
4470 // (like both named and anonymous pipes, such as pipes
4471 // connected to an exec'd process).
4472 // Standard Input is a special case.
4473 HANDLE han;
4474
4475 if ((han = (HANDLE) ::_get_osfhandle(fd)) == (HANDLE)(-1)) {
4476 return FALSE;
4477 }
4478
4479 if (! ::PeekNamedPipe(han, NULL, 0, NULL, (LPDWORD)pbytes, NULL)) {
4480 // PeekNamedPipe fails when at EOF. In that case we
4481 // simply make *pbytes = 0 which is consistent with the
4482 // behavior we get on Solaris when an fd is at EOF.
4483 // The only alternative is to raise an Exception,
4484 // which isn't really warranted.
4485 //
4486 if (::GetLastError() != ERROR_BROKEN_PIPE) {
4487 return FALSE;
4488 }
4489 *pbytes = 0;
4490 }
4491 return TRUE;
4492 }
4493
4494 #define MAX_INPUT_EVENTS 2000
4495
4496 // This code is a copy of JDK's stdinAvailable
4497 // from src/windows/hpi/src/sys_api_md.c
4498
4499 static int stdinAvailable(int fd, long *pbytes) {
4500 HANDLE han;
4501 DWORD numEventsRead = 0; // Number of events read from buffer
4502 DWORD numEvents = 0; // Number of events in buffer
4503 DWORD i = 0; // Loop index
4504 DWORD curLength = 0; // Position marker
4505 DWORD actualLength = 0; // Number of bytes readable
4506 BOOL error = FALSE; // Error holder
4507 INPUT_RECORD *lpBuffer; // Pointer to records of input events
4508
4509 if ((han = ::GetStdHandle(STD_INPUT_HANDLE)) == INVALID_HANDLE_VALUE) {
4510 return FALSE;
4511 }
4512
4513 // Construct an array of input records in the console buffer
4514 error = ::GetNumberOfConsoleInputEvents(han, &numEvents);
4515 if (error == 0) {
4516 return nonSeekAvailable(fd, pbytes);
4517 }
4518
4519 // lpBuffer must fit into 64K or else PeekConsoleInput fails
4520 if (numEvents > MAX_INPUT_EVENTS) {
4521 numEvents = MAX_INPUT_EVENTS;
4522 }
4523
4524 lpBuffer = (INPUT_RECORD *)os::malloc(numEvents * sizeof(INPUT_RECORD), mtInternal);
4525 if (lpBuffer == NULL) {
4526 return FALSE;
4527 }
4528
4529 error = ::PeekConsoleInput(han, lpBuffer, numEvents, &numEventsRead);
4530 if (error == 0) {
4531 os::free(lpBuffer);
4532 return FALSE;
4533 }
4534
4535 // Examine input records for the number of bytes available
4536 for (i=0; i<numEvents; i++) {
4537 if (lpBuffer[i].EventType == KEY_EVENT) {
4538
4539 KEY_EVENT_RECORD *keyRecord = (KEY_EVENT_RECORD *)
4540 &(lpBuffer[i].Event);
4541 if (keyRecord->bKeyDown == TRUE) {
4542 CHAR *keyPressed = (CHAR *) &(keyRecord->uChar);
4543 curLength++;
4544 if (*keyPressed == '\r') {
4545 actualLength = curLength;
4546 }
4547 }
4548 }
4549 }
4550
4551 if (lpBuffer != NULL) {
4552 os::free(lpBuffer);
4553 }
4554
4555 *pbytes = (long) actualLength;
4556 return TRUE;
4557 }
4558
4559 // Map a block of memory.
4560 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
4561 char *addr, size_t bytes, bool read_only,
4562 bool allow_exec) {
4563 HANDLE hFile;
4564 char* base;
4565
4566 hFile = CreateFile(file_name, GENERIC_READ, FILE_SHARE_READ, NULL,
4567 OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
4568 if (hFile == NULL) {
4569 log_info(os)("CreateFile() failed: GetLastError->%ld.", GetLastError());
4570 return NULL;
4571 }
4572
4573 if (allow_exec) {
4574 // CreateFileMapping/MapViewOfFileEx can't map executable memory
4575 // unless it comes from a PE image (which the shared archive is not.)
4576 // Even VirtualProtect refuses to give execute access to mapped memory
4577 // that was not previously executable.
4578 //
4579 // Instead, stick the executable region in anonymous memory. Yuck.
4580 // Penalty is that ~4 pages will not be shareable - in the future
4581 // we might consider DLLizing the shared archive with a proper PE
4582 // header so that mapping executable + sharing is possible.
4583
4584 base = (char*) VirtualAlloc(addr, bytes, MEM_COMMIT | MEM_RESERVE,
4585 PAGE_READWRITE);
4586 if (base == NULL) {
4587 log_info(os)("VirtualAlloc() failed: GetLastError->%ld.", GetLastError());
4588 CloseHandle(hFile);
4589 return NULL;
4590 }
4591
4592 DWORD bytes_read;
4593 OVERLAPPED overlapped;
4594 overlapped.Offset = (DWORD)file_offset;
4595 overlapped.OffsetHigh = 0;
4596 overlapped.hEvent = NULL;
4597 // ReadFile guarantees that if the return value is true, the requested
4598 // number of bytes were read before returning.
4599 bool res = ReadFile(hFile, base, (DWORD)bytes, &bytes_read, &overlapped) != 0;
4600 if (!res) {
4601 log_info(os)("ReadFile() failed: GetLastError->%ld.", GetLastError());
4602 release_memory(base, bytes);
4603 CloseHandle(hFile);
4604 return NULL;
4605 }
4606 } else {
4607 HANDLE hMap = CreateFileMapping(hFile, NULL, PAGE_WRITECOPY, 0, 0,
4608 NULL /* file_name */);
4609 if (hMap == NULL) {
4610 log_info(os)("CreateFileMapping() failed: GetLastError->%ld.", GetLastError());
4611 CloseHandle(hFile);
4612 return NULL;
4613 }
4614
4615 DWORD access = read_only ? FILE_MAP_READ : FILE_MAP_COPY;
4616 base = (char*)MapViewOfFileEx(hMap, access, 0, (DWORD)file_offset,
4617 (DWORD)bytes, addr);
4618 if (base == NULL) {
4619 log_info(os)("MapViewOfFileEx() failed: GetLastError->%ld.", GetLastError());
4620 CloseHandle(hMap);
4621 CloseHandle(hFile);
4622 return NULL;
4623 }
4624
4625 if (CloseHandle(hMap) == 0) {
4626 log_info(os)("CloseHandle(hMap) failed: GetLastError->%ld.", GetLastError());
4627 CloseHandle(hFile);
4628 return base;
4629 }
4630 }
4631
4632 if (allow_exec) {
4633 DWORD old_protect;
4634 DWORD exec_access = read_only ? PAGE_EXECUTE_READ : PAGE_EXECUTE_READWRITE;
4635 bool res = VirtualProtect(base, bytes, exec_access, &old_protect) != 0;
4636
4637 if (!res) {
4638 log_info(os)("VirtualProtect() failed: GetLastError->%ld.", GetLastError());
4639 // Don't consider this a hard error, on IA32 even if the
4640 // VirtualProtect fails, we should still be able to execute
4641 CloseHandle(hFile);
4642 return base;
4643 }
4644 }
4645
4646 if (CloseHandle(hFile) == 0) {
4647 log_info(os)("CloseHandle(hFile) failed: GetLastError->%ld.", GetLastError());
4648 return base;
4649 }
4650
4651 return base;
4652 }
4653
4654
4655 // Remap a block of memory.
4656 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
4657 char *addr, size_t bytes, bool read_only,
4658 bool allow_exec) {
4659 // This OS does not allow existing memory maps to be remapped so we
4660 // have to unmap the memory before we remap it.
4661 if (!os::unmap_memory(addr, bytes)) {
4662 return NULL;
4663 }
4664
4665 // There is a very small theoretical window between the unmap_memory()
4666 // call above and the map_memory() call below where a thread in native
4667 // code may be able to access an address that is no longer mapped.
4668
4669 return os::map_memory(fd, file_name, file_offset, addr, bytes,
4670 read_only, allow_exec);
4671 }
4672
4673
4674 // Unmap a block of memory.
4675 // Returns true=success, otherwise false.
4676
4677 bool os::pd_unmap_memory(char* addr, size_t bytes) {
4678 MEMORY_BASIC_INFORMATION mem_info;
4679 if (VirtualQuery(addr, &mem_info, sizeof(mem_info)) == 0) {
4680 log_info(os)("VirtualQuery() failed: GetLastError->%ld.", GetLastError());
4681 return false;
4682 }
4683
4684 // Executable memory was not mapped using CreateFileMapping/MapViewOfFileEx.
4685 // Instead, executable region was allocated using VirtualAlloc(). See
4686 // pd_map_memory() above.
4687 //
4688 // The following flags should match the 'exec_access' flages used for
4689 // VirtualProtect() in pd_map_memory().
4690 if (mem_info.Protect == PAGE_EXECUTE_READ ||
4691 mem_info.Protect == PAGE_EXECUTE_READWRITE) {
4692 return pd_release_memory(addr, bytes);
4693 }
4694
4695 BOOL result = UnmapViewOfFile(addr);
4696 if (result == 0) {
4697 log_info(os)("UnmapViewOfFile() failed: GetLastError->%ld.", GetLastError());
4698 return false;
4699 }
4700 return true;
4701 }
4702
4703 void os::pause() {
4704 char filename[MAX_PATH];
4705 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
4706 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
4707 } else {
4708 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
4709 }
4710
4711 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
4712 if (fd != -1) {
4713 struct stat buf;
4714 ::close(fd);
4715 while (::stat(filename, &buf) == 0) {
4716 Sleep(100);
4717 }
4718 } else {
4719 jio_fprintf(stderr,
4720 "Could not open pause file '%s', continuing immediately.\n", filename);
4721 }
4722 }
4723
4724 Thread* os::ThreadCrashProtection::_protected_thread = NULL;
4725 os::ThreadCrashProtection* os::ThreadCrashProtection::_crash_protection = NULL;
4726 volatile intptr_t os::ThreadCrashProtection::_crash_mux = 0;
4727
4728 os::ThreadCrashProtection::ThreadCrashProtection() {
4729 }
4730
4731 // See the caveats for this class in os_windows.hpp
4732 // Protects the callback call so that raised OS EXCEPTIONS causes a jump back
4733 // into this method and returns false. If no OS EXCEPTION was raised, returns
4734 // true.
4735 // The callback is supposed to provide the method that should be protected.
4736 //
4737 bool os::ThreadCrashProtection::call(os::CrashProtectionCallback& cb) {
4738
4739 Thread::muxAcquire(&_crash_mux, "CrashProtection");
4740
4741 _protected_thread = Thread::current_or_null();
4742 assert(_protected_thread != NULL, "Cannot crash protect a NULL thread");
4743
4744 bool success = true;
4745 __try {
4746 _crash_protection = this;
4747 cb.call();
4748 } __except(EXCEPTION_EXECUTE_HANDLER) {
4749 // only for protection, nothing to do
4750 success = false;
4751 }
4752 _crash_protection = NULL;
4753 _protected_thread = NULL;
4754 Thread::muxRelease(&_crash_mux);
4755 return success;
4756 }
4757
4758 // An Event wraps a win32 "CreateEvent" kernel handle.
4759 //
4760 // We have a number of choices regarding "CreateEvent" win32 handle leakage:
4761 //
4762 // 1: When a thread dies return the Event to the EventFreeList, clear the ParkHandle
4763 // field, and call CloseHandle() on the win32 event handle. Unpark() would
4764 // need to be modified to tolerate finding a NULL (invalid) win32 event handle.
4765 // In addition, an unpark() operation might fetch the handle field, but the
4766 // event could recycle between the fetch and the SetEvent() operation.
4767 // SetEvent() would either fail because the handle was invalid, or inadvertently work,
4768 // as the win32 handle value had been recycled. In an ideal world calling SetEvent()
4769 // on an stale but recycled handle would be harmless, but in practice this might
4770 // confuse other non-Sun code, so it's not a viable approach.
4771 //
4772 // 2: Once a win32 event handle is associated with an Event, it remains associated
4773 // with the Event. The event handle is never closed. This could be construed
4774 // as handle leakage, but only up to the maximum # of threads that have been extant
4775 // at any one time. This shouldn't be an issue, as windows platforms typically
4776 // permit a process to have hundreds of thousands of open handles.
4777 //
4778 // 3: Same as (1), but periodically, at stop-the-world time, rundown the EventFreeList
4779 // and release unused handles.
4780 //
4781 // 4: Add a CRITICAL_SECTION to the Event to protect LD+SetEvent from LD;ST(null);CloseHandle.
4782 // It's not clear, however, that we wouldn't be trading one type of leak for another.
4783 //
4784 // 5. Use an RCU-like mechanism (Read-Copy Update).
4785 // Or perhaps something similar to Maged Michael's "Hazard pointers".
4786 //
4787 // We use (2).
4788 //
4789 // TODO-FIXME:
4790 // 1. Reconcile Doug's JSR166 j.u.c park-unpark with the objectmonitor implementation.
4791 // 2. Consider wrapping the WaitForSingleObject(Ex) calls in SEH try/finally blocks
4792 // to recover from (or at least detect) the dreaded Windows 841176 bug.
4793 // 3. Collapse the interrupt_event, the JSR166 parker event, and the objectmonitor ParkEvent
4794 // into a single win32 CreateEvent() handle.
4795 //
4796 // Assumption:
4797 // Only one parker can exist on an event, which is why we allocate
4798 // them per-thread. Multiple unparkers can coexist.
4799 //
4800 // _Event transitions in park()
4801 // -1 => -1 : illegal
4802 // 1 => 0 : pass - return immediately
4803 // 0 => -1 : block; then set _Event to 0 before returning
4804 //
4805 // _Event transitions in unpark()
4806 // 0 => 1 : just return
4807 // 1 => 1 : just return
4808 // -1 => either 0 or 1; must signal target thread
4809 // That is, we can safely transition _Event from -1 to either
4810 // 0 or 1.
4811 //
4812 // _Event serves as a restricted-range semaphore.
4813 // -1 : thread is blocked, i.e. there is a waiter
4814 // 0 : neutral: thread is running or ready,
4815 // could have been signaled after a wait started
4816 // 1 : signaled - thread is running or ready
4817 //
4818 // Another possible encoding of _Event would be with
4819 // explicit "PARKED" == 01b and "SIGNALED" == 10b bits.
4820 //
4821
4822 int os::PlatformEvent::park(jlong Millis) {
4823 // Transitions for _Event:
4824 // -1 => -1 : illegal
4825 // 1 => 0 : pass - return immediately
4826 // 0 => -1 : block; then set _Event to 0 before returning
4827
4828 guarantee(_ParkHandle != NULL , "Invariant");
4829 guarantee(Millis > 0 , "Invariant");
4830
4831 // CONSIDER: defer assigning a CreateEvent() handle to the Event until
4832 // the initial park() operation.
4833 // Consider: use atomic decrement instead of CAS-loop
4834
4835 int v;
4836 for (;;) {
4837 v = _Event;
4838 if (Atomic::cmpxchg(v-1, &_Event, v) == v) break;
4839 }
4840 guarantee((v == 0) || (v == 1), "invariant");
4841 if (v != 0) return OS_OK;
4842
4843 // Do this the hard way by blocking ...
4844 // TODO: consider a brief spin here, gated on the success of recent
4845 // spin attempts by this thread.
4846 //
4847 // We decompose long timeouts into series of shorter timed waits.
4848 // Evidently large timo values passed in WaitForSingleObject() are problematic on some
4849 // versions of Windows. See EventWait() for details. This may be superstition. Or not.
4850 // We trust the WAIT_TIMEOUT indication and don't track the elapsed wait time
4851 // with os::javaTimeNanos(). Furthermore, we assume that spurious returns from
4852 // ::WaitForSingleObject() caused by latent ::setEvent() operations will tend
4853 // to happen early in the wait interval. Specifically, after a spurious wakeup (rv ==
4854 // WAIT_OBJECT_0 but _Event is still < 0) we don't bother to recompute Millis to compensate
4855 // for the already waited time. This policy does not admit any new outcomes.
4856 // In the future, however, we might want to track the accumulated wait time and
4857 // adjust Millis accordingly if we encounter a spurious wakeup.
4858
4859 const int MAXTIMEOUT = 0x10000000;
4860 DWORD rv = WAIT_TIMEOUT;
4861 while (_Event < 0 && Millis > 0) {
4862 DWORD prd = Millis; // set prd = MAX (Millis, MAXTIMEOUT)
4863 if (Millis > MAXTIMEOUT) {
4864 prd = MAXTIMEOUT;
4865 }
4866 rv = ::WaitForSingleObject(_ParkHandle, prd);
4867 assert(rv == WAIT_OBJECT_0 || rv == WAIT_TIMEOUT, "WaitForSingleObject failed");
4868 if (rv == WAIT_TIMEOUT) {
4869 Millis -= prd;
4870 }
4871 }
4872 v = _Event;
4873 _Event = 0;
4874 // see comment at end of os::PlatformEvent::park() below:
4875 OrderAccess::fence();
4876 // If we encounter a nearly simultanous timeout expiry and unpark()
4877 // we return OS_OK indicating we awoke via unpark().
4878 // Implementor's license -- returning OS_TIMEOUT would be equally valid, however.
4879 return (v >= 0) ? OS_OK : OS_TIMEOUT;
4880 }
4881
4882 void os::PlatformEvent::park() {
4883 // Transitions for _Event:
4884 // -1 => -1 : illegal
4885 // 1 => 0 : pass - return immediately
4886 // 0 => -1 : block; then set _Event to 0 before returning
4887
4888 guarantee(_ParkHandle != NULL, "Invariant");
4889 // Invariant: Only the thread associated with the Event/PlatformEvent
4890 // may call park().
4891 // Consider: use atomic decrement instead of CAS-loop
4892 int v;
4893 for (;;) {
4894 v = _Event;
4895 if (Atomic::cmpxchg(v-1, &_Event, v) == v) break;
4896 }
4897 guarantee((v == 0) || (v == 1), "invariant");
4898 if (v != 0) return;
4899
4900 // Do this the hard way by blocking ...
4901 // TODO: consider a brief spin here, gated on the success of recent
4902 // spin attempts by this thread.
4903 while (_Event < 0) {
4904 DWORD rv = ::WaitForSingleObject(_ParkHandle, INFINITE);
4905 assert(rv == WAIT_OBJECT_0, "WaitForSingleObject failed");
4906 }
4907
4908 // Usually we'll find _Event == 0 at this point, but as
4909 // an optional optimization we clear it, just in case can
4910 // multiple unpark() operations drove _Event up to 1.
4911 _Event = 0;
4912 OrderAccess::fence();
4913 guarantee(_Event >= 0, "invariant");
4914 }
4915
4916 void os::PlatformEvent::unpark() {
4917 guarantee(_ParkHandle != NULL, "Invariant");
4918
4919 // Transitions for _Event:
4920 // 0 => 1 : just return
4921 // 1 => 1 : just return
4922 // -1 => either 0 or 1; must signal target thread
4923 // That is, we can safely transition _Event from -1 to either
4924 // 0 or 1.
4925 // See also: "Semaphores in Plan 9" by Mullender & Cox
4926 //
4927 // Note: Forcing a transition from "-1" to "1" on an unpark() means
4928 // that it will take two back-to-back park() calls for the owning
4929 // thread to block. This has the benefit of forcing a spurious return
4930 // from the first park() call after an unpark() call which will help
4931 // shake out uses of park() and unpark() without condition variables.
4932
4933 if (Atomic::xchg(1, &_Event) >= 0) return;
4934
4935 ::SetEvent(_ParkHandle);
4936 }
4937
4938
4939 // JSR166
4940 // -------------------------------------------------------
4941
4942 // The Windows implementation of Park is very straightforward: Basic
4943 // operations on Win32 Events turn out to have the right semantics to
4944 // use them directly. We opportunistically resuse the event inherited
4945 // from Monitor.
4946
4947 void Parker::park(bool isAbsolute, jlong time) {
4948 guarantee(_ParkEvent != NULL, "invariant");
4949 // First, demultiplex/decode time arguments
4950 if (time < 0) { // don't wait
4951 return;
4952 } else if (time == 0 && !isAbsolute) {
4953 time = INFINITE;
4954 } else if (isAbsolute) {
4955 time -= os::javaTimeMillis(); // convert to relative time
4956 if (time <= 0) { // already elapsed
4957 return;
4958 }
4959 } else { // relative
4960 time /= 1000000; // Must coarsen from nanos to millis
4961 if (time == 0) { // Wait for the minimal time unit if zero
4962 time = 1;
4963 }
4964 }
4965
4966 JavaThread* thread = JavaThread::current();
4967
4968 // Don't wait if interrupted or already triggered
4969 if (Thread::is_interrupted(thread, false) ||
4970 WaitForSingleObject(_ParkEvent, 0) == WAIT_OBJECT_0) {
4971 ResetEvent(_ParkEvent);
4972 return;
4973 } else {
4974 ThreadBlockInVM tbivm(thread);
4975 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
4976 thread->set_suspend_equivalent();
4977
4978 WaitForSingleObject(_ParkEvent, time);
4979 ResetEvent(_ParkEvent);
4980
4981 // If externally suspended while waiting, re-suspend
4982 if (thread->handle_special_suspend_equivalent_condition()) {
4983 thread->java_suspend_self();
4984 }
4985 }
4986 }
4987
4988 void Parker::unpark() {
4989 guarantee(_ParkEvent != NULL, "invariant");
4990 SetEvent(_ParkEvent);
4991 }
4992
4993 // Run the specified command in a separate process. Return its exit value,
4994 // or -1 on failure (e.g. can't create a new process).
4995 int os::fork_and_exec(char* cmd) {
4996 STARTUPINFO si;
4997 PROCESS_INFORMATION pi;
4998 DWORD exit_code;
4999
5000 char * cmd_string;
5001 char * cmd_prefix = "cmd /C ";
5002 size_t len = strlen(cmd) + strlen(cmd_prefix) + 1;
5003 cmd_string = NEW_C_HEAP_ARRAY_RETURN_NULL(char, len, mtInternal);
5004 if (cmd_string == NULL) {
5005 return -1;
5006 }
5007 cmd_string[0] = '\0';
5008 strcat(cmd_string, cmd_prefix);
5009 strcat(cmd_string, cmd);
5010
5011 // now replace all '\n' with '&'
5012 char * substring = cmd_string;
5013 while ((substring = strchr(substring, '\n')) != NULL) {
5014 substring[0] = '&';
5015 substring++;
5016 }
5017 memset(&si, 0, sizeof(si));
5018 si.cb = sizeof(si);
5019 memset(&pi, 0, sizeof(pi));
5020 BOOL rslt = CreateProcess(NULL, // executable name - use command line
5021 cmd_string, // command line
5022 NULL, // process security attribute
5023 NULL, // thread security attribute
5024 TRUE, // inherits system handles
5025 0, // no creation flags
5026 NULL, // use parent's environment block
5027 NULL, // use parent's starting directory
5028 &si, // (in) startup information
5029 &pi); // (out) process information
5030
5031 if (rslt) {
5032 // Wait until child process exits.
5033 WaitForSingleObject(pi.hProcess, INFINITE);
5034
5035 GetExitCodeProcess(pi.hProcess, &exit_code);
5036
5037 // Close process and thread handles.
5038 CloseHandle(pi.hProcess);
5039 CloseHandle(pi.hThread);
5040 } else {
5041 exit_code = -1;
5042 }
5043
5044 FREE_C_HEAP_ARRAY(char, cmd_string);
5045 return (int)exit_code;
5046 }
5047
5048 bool os::find(address addr, outputStream* st) {
5049 int offset = -1;
5050 bool result = false;
5051 char buf[256];
5052 if (os::dll_address_to_library_name(addr, buf, sizeof(buf), &offset)) {
5053 st->print(PTR_FORMAT " ", addr);
5054 if (strlen(buf) < sizeof(buf) - 1) {
5055 char* p = strrchr(buf, '\\');
5056 if (p) {
5057 st->print("%s", p + 1);
5058 } else {
5059 st->print("%s", buf);
5060 }
5061 } else {
5062 // The library name is probably truncated. Let's omit the library name.
5063 // See also JDK-8147512.
5064 }
5065 if (os::dll_address_to_function_name(addr, buf, sizeof(buf), &offset)) {
5066 st->print("::%s + 0x%x", buf, offset);
5067 }
5068 st->cr();
5069 result = true;
5070 }
5071 return result;
5072 }
5073
5074 LONG WINAPI os::win32::serialize_fault_filter(struct _EXCEPTION_POINTERS* e) {
5075 DWORD exception_code = e->ExceptionRecord->ExceptionCode;
5076
5077 if (exception_code == EXCEPTION_ACCESS_VIOLATION) {
5078 JavaThread* thread = JavaThread::current();
5079 PEXCEPTION_RECORD exceptionRecord = e->ExceptionRecord;
5080 address addr = (address) exceptionRecord->ExceptionInformation[1];
5081
5082 if (os::is_memory_serialize_page(thread, addr)) {
5083 return EXCEPTION_CONTINUE_EXECUTION;
5084 }
5085 }
5086
5087 return EXCEPTION_CONTINUE_SEARCH;
5088 }
5089
5090 // We don't build a headless jre for Windows
5091 bool os::is_headless_jre() { return false; }
5092
5093 static jint initSock() {
5094 WSADATA wsadata;
5095
5096 if (WSAStartup(MAKEWORD(2,2), &wsadata) != 0) {
5097 jio_fprintf(stderr, "Could not initialize Winsock (error: %d)\n",
5098 ::GetLastError());
5099 return JNI_ERR;
5100 }
5101 return JNI_OK;
5102 }
5103
5104 struct hostent* os::get_host_by_name(char* name) {
5105 return (struct hostent*)gethostbyname(name);
5106 }
5107
5108 int os::socket_close(int fd) {
5109 return ::closesocket(fd);
5110 }
5111
5112 int os::socket(int domain, int type, int protocol) {
5113 return ::socket(domain, type, protocol);
5114 }
5115
5116 int os::connect(int fd, struct sockaddr* him, socklen_t len) {
5117 return ::connect(fd, him, len);
5118 }
5119
5120 int os::recv(int fd, char* buf, size_t nBytes, uint flags) {
5121 return ::recv(fd, buf, (int)nBytes, flags);
5122 }
5123
5124 int os::send(int fd, char* buf, size_t nBytes, uint flags) {
5125 return ::send(fd, buf, (int)nBytes, flags);
5126 }
5127
5128 int os::raw_send(int fd, char* buf, size_t nBytes, uint flags) {
5129 return ::send(fd, buf, (int)nBytes, flags);
5130 }
5131
5132 // WINDOWS CONTEXT Flags for THREAD_SAMPLING
5133 #if defined(IA32)
5134 #define sampling_context_flags (CONTEXT_FULL | CONTEXT_FLOATING_POINT | CONTEXT_EXTENDED_REGISTERS)
5135 #elif defined (AMD64)
5136 #define sampling_context_flags (CONTEXT_FULL | CONTEXT_FLOATING_POINT)
5137 #endif
5138
5139 // returns true if thread could be suspended,
5140 // false otherwise
5141 static bool do_suspend(HANDLE* h) {
5142 if (h != NULL) {
5143 if (SuspendThread(*h) != ~0) {
5144 return true;
5145 }
5146 }
5147 return false;
5148 }
5149
5150 // resume the thread
5151 // calling resume on an active thread is a no-op
5152 static void do_resume(HANDLE* h) {
5153 if (h != NULL) {
5154 ResumeThread(*h);
5155 }
5156 }
5157
5158 // retrieve a suspend/resume context capable handle
5159 // from the tid. Caller validates handle return value.
5160 void get_thread_handle_for_extended_context(HANDLE* h,
5161 OSThread::thread_id_t tid) {
5162 if (h != NULL) {
5163 *h = OpenThread(THREAD_SUSPEND_RESUME | THREAD_GET_CONTEXT | THREAD_QUERY_INFORMATION, FALSE, tid);
5164 }
5165 }
5166
5167 // Thread sampling implementation
5168 //
5169 void os::SuspendedThreadTask::internal_do_task() {
5170 CONTEXT ctxt;
5171 HANDLE h = NULL;
5172
5173 // get context capable handle for thread
5174 get_thread_handle_for_extended_context(&h, _thread->osthread()->thread_id());
5175
5176 // sanity
5177 if (h == NULL || h == INVALID_HANDLE_VALUE) {
5178 return;
5179 }
5180
5181 // suspend the thread
5182 if (do_suspend(&h)) {
5183 ctxt.ContextFlags = sampling_context_flags;
5184 // get thread context
5185 GetThreadContext(h, &ctxt);
5186 SuspendedThreadTaskContext context(_thread, &ctxt);
5187 // pass context to Thread Sampling impl
5188 do_task(context);
5189 // resume thread
5190 do_resume(&h);
5191 }
5192
5193 // close handle
5194 CloseHandle(h);
5195 }
5196
5197 bool os::start_debugging(char *buf, int buflen) {
5198 int len = (int)strlen(buf);
5199 char *p = &buf[len];
5200
5201 jio_snprintf(p, buflen-len,
5202 "\n\n"
5203 "Do you want to debug the problem?\n\n"
5204 "To debug, attach Visual Studio to process %d; then switch to thread 0x%x\n"
5205 "Select 'Yes' to launch Visual Studio automatically (PATH must include msdev)\n"
5206 "Otherwise, select 'No' to abort...",
5207 os::current_process_id(), os::current_thread_id());
5208
5209 bool yes = os::message_box("Unexpected Error", buf);
5210
5211 if (yes) {
5212 // os::breakpoint() calls DebugBreak(), which causes a breakpoint
5213 // exception. If VM is running inside a debugger, the debugger will
5214 // catch the exception. Otherwise, the breakpoint exception will reach
5215 // the default windows exception handler, which can spawn a debugger and
5216 // automatically attach to the dying VM.
5217 os::breakpoint();
5218 yes = false;
5219 }
5220 return yes;
5221 }
5222
5223 void* os::get_default_process_handle() {
5224 return (void*)GetModuleHandle(NULL);
5225 }
5226
5227 // Builds a platform dependent Agent_OnLoad_<lib_name> function name
5228 // which is used to find statically linked in agents.
5229 // Additionally for windows, takes into account __stdcall names.
5230 // Parameters:
5231 // sym_name: Symbol in library we are looking for
5232 // lib_name: Name of library to look in, NULL for shared libs.
5233 // is_absolute_path == true if lib_name is absolute path to agent
5234 // such as "C:/a/b/L.dll"
5235 // == false if only the base name of the library is passed in
5236 // such as "L"
5237 char* os::build_agent_function_name(const char *sym_name, const char *lib_name,
5238 bool is_absolute_path) {
5239 char *agent_entry_name;
5240 size_t len;
5241 size_t name_len;
5242 size_t prefix_len = strlen(JNI_LIB_PREFIX);
5243 size_t suffix_len = strlen(JNI_LIB_SUFFIX);
5244 const char *start;
5245
5246 if (lib_name != NULL) {
5247 len = name_len = strlen(lib_name);
5248 if (is_absolute_path) {
5249 // Need to strip path, prefix and suffix
5250 if ((start = strrchr(lib_name, *os::file_separator())) != NULL) {
5251 lib_name = ++start;
5252 } else {
5253 // Need to check for drive prefix
5254 if ((start = strchr(lib_name, ':')) != NULL) {
5255 lib_name = ++start;
5256 }
5257 }
5258 if (len <= (prefix_len + suffix_len)) {
5259 return NULL;
5260 }
5261 lib_name += prefix_len;
5262 name_len = strlen(lib_name) - suffix_len;
5263 }
5264 }
5265 len = (lib_name != NULL ? name_len : 0) + strlen(sym_name) + 2;
5266 agent_entry_name = NEW_C_HEAP_ARRAY_RETURN_NULL(char, len, mtThread);
5267 if (agent_entry_name == NULL) {
5268 return NULL;
5269 }
5270 if (lib_name != NULL) {
5271 const char *p = strrchr(sym_name, '@');
5272 if (p != NULL && p != sym_name) {
5273 // sym_name == _Agent_OnLoad@XX
5274 strncpy(agent_entry_name, sym_name, (p - sym_name));
5275 agent_entry_name[(p-sym_name)] = '\0';
5276 // agent_entry_name == _Agent_OnLoad
5277 strcat(agent_entry_name, "_");
5278 strncat(agent_entry_name, lib_name, name_len);
5279 strcat(agent_entry_name, p);
5280 // agent_entry_name == _Agent_OnLoad_lib_name@XX
5281 } else {
5282 strcpy(agent_entry_name, sym_name);
5283 strcat(agent_entry_name, "_");
5284 strncat(agent_entry_name, lib_name, name_len);
5285 }
5286 } else {
5287 strcpy(agent_entry_name, sym_name);
5288 }
5289 return agent_entry_name;
5290 }
5291
5292 #ifndef PRODUCT
5293
5294 // test the code path in reserve_memory_special() that tries to allocate memory in a single
5295 // contiguous memory block at a particular address.
5296 // The test first tries to find a good approximate address to allocate at by using the same
5297 // method to allocate some memory at any address. The test then tries to allocate memory in
5298 // the vicinity (not directly after it to avoid possible by-chance use of that location)
5299 // This is of course only some dodgy assumption, there is no guarantee that the vicinity of
5300 // the previously allocated memory is available for allocation. The only actual failure
5301 // that is reported is when the test tries to allocate at a particular location but gets a
5302 // different valid one. A NULL return value at this point is not considered an error but may
5303 // be legitimate.
5304 // If -XX:+VerboseInternalVMTests is enabled, print some explanatory messages.
5305 void TestReserveMemorySpecial_test() {
5306 if (!UseLargePages) {
5307 if (VerboseInternalVMTests) {
5308 tty->print("Skipping test because large pages are disabled");
5309 }
5310 return;
5311 }
5312 // save current value of globals
5313 bool old_use_large_pages_individual_allocation = UseLargePagesIndividualAllocation;
5314 bool old_use_numa_interleaving = UseNUMAInterleaving;
5315
5316 // set globals to make sure we hit the correct code path
5317 UseLargePagesIndividualAllocation = UseNUMAInterleaving = false;
5318
5319 // do an allocation at an address selected by the OS to get a good one.
5320 const size_t large_allocation_size = os::large_page_size() * 4;
5321 char* result = os::reserve_memory_special(large_allocation_size, os::large_page_size(), NULL, false);
5322 if (result == NULL) {
5323 if (VerboseInternalVMTests) {
5324 tty->print("Failed to allocate control block with size " SIZE_FORMAT ". Skipping remainder of test.",
5325 large_allocation_size);
5326 }
5327 } else {
5328 os::release_memory_special(result, large_allocation_size);
5329
5330 // allocate another page within the recently allocated memory area which seems to be a good location. At least
5331 // we managed to get it once.
5332 const size_t expected_allocation_size = os::large_page_size();
5333 char* expected_location = result + os::large_page_size();
5334 char* actual_location = os::reserve_memory_special(expected_allocation_size, os::large_page_size(), expected_location, false);
5335 if (actual_location == NULL) {
5336 if (VerboseInternalVMTests) {
5337 tty->print("Failed to allocate any memory at " PTR_FORMAT " size " SIZE_FORMAT ". Skipping remainder of test.",
5338 expected_location, large_allocation_size);
5339 }
5340 } else {
5341 // release memory
5342 os::release_memory_special(actual_location, expected_allocation_size);
5343 // only now check, after releasing any memory to avoid any leaks.
5344 assert(actual_location == expected_location,
5345 "Failed to allocate memory at requested location " PTR_FORMAT " of size " SIZE_FORMAT ", is " PTR_FORMAT " instead",
5346 expected_location, expected_allocation_size, actual_location);
5347 }
5348 }
5349
5350 // restore globals
5351 UseLargePagesIndividualAllocation = old_use_large_pages_individual_allocation;
5352 UseNUMAInterleaving = old_use_numa_interleaving;
5353 }
5354 #endif // PRODUCT
5355
5356 /*
5357 All the defined signal names for Windows.
5358
5359 NOTE that not all of these names are accepted by FindSignal!
5360
5361 For various reasons some of these may be rejected at runtime.
5362
5363 Here are the names currently accepted by a user of sun.misc.Signal with
5364 1.4.1 (ignoring potential interaction with use of chaining, etc):
5365
5366 (LIST TBD)
5367
5368 */
5369 int os::get_signal_number(const char* name) {
5370 static const struct {
5371 char* name;
5372 int number;
5373 } siglabels [] =
5374 // derived from version 6.0 VC98/include/signal.h
5375 {"ABRT", SIGABRT, // abnormal termination triggered by abort cl
5376 "FPE", SIGFPE, // floating point exception
5377 "SEGV", SIGSEGV, // segment violation
5378 "INT", SIGINT, // interrupt
5379 "TERM", SIGTERM, // software term signal from kill
5380 "BREAK", SIGBREAK, // Ctrl-Break sequence
5381 "ILL", SIGILL}; // illegal instruction
5382 for (unsigned i = 0; i < ARRAY_SIZE(siglabels); ++i) {
5383 if (strcmp(name, siglabels[i].name) == 0) {
5384 return siglabels[i].number;
5385 }
5386 }
5387 return -1;
5388 }
5389
5390 // Fast current thread access
5391
5392 int os::win32::_thread_ptr_offset = 0;
5393
5394 static void call_wrapper_dummy() {}
5395
5396 // We need to call the os_exception_wrapper once so that it sets
5397 // up the offset from FS of the thread pointer.
5398 void os::win32::initialize_thread_ptr_offset() {
5399 os::os_exception_wrapper((java_call_t)call_wrapper_dummy,
5400 NULL, NULL, NULL, NULL);
5401 }