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 "jvm.h"
30 #include "classfile/classLoader.hpp"
31 #include "classfile/systemDictionary.hpp"
32 #include "classfile/vmSymbols.hpp"
33 #include "code/icBuffer.hpp"
34 #include "code/vtableStubs.hpp"
35 #include "compiler/compileBroker.hpp"
36 #include "compiler/disassembler.hpp"
37 #include "interpreter/interpreter.hpp"
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_misc.hpp"
46 #include "runtime/arguments.hpp"
47 #include "runtime/atomic.hpp"
48 #include "runtime/extendedPC.hpp"
49 #include "runtime/globals.hpp"
50 #include "runtime/interfaceSupport.hpp"
51 #include "runtime/java.hpp"
52 #include "runtime/javaCalls.hpp"
53 #include "runtime/mutexLocker.hpp"
54 #include "runtime/objectMonitor.hpp"
55 #include "runtime/orderAccess.inline.hpp"
56 #include "runtime/osThread.hpp"
57 #include "runtime/perfMemory.hpp"
58 #include "runtime/sharedRuntime.hpp"
59 #include "runtime/statSampler.hpp"
60 #include "runtime/stubRoutines.hpp"
61 #include "runtime/thread.inline.hpp"
62 #include "runtime/threadCritical.hpp"
63 #include "runtime/timer.hpp"
64 #include "runtime/vm_version.hpp"
65 #include "semaphore_windows.hpp"
66 #include "services/attachListener.hpp"
67 #include "services/memTracker.hpp"
68 #include "services/runtimeService.hpp"
69 #include "utilities/align.hpp"
70 #include "utilities/decoder.hpp"
71 #include "utilities/defaultStream.hpp"
72 #include "utilities/events.hpp"
73 #include "utilities/growableArray.hpp"
74 #include "utilities/macros.hpp"
75 #include "utilities/vmError.hpp"
76 #include "symbolengine.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 #include <psapi.h>
103
104 // for timer info max values which include all bits
105 #define ALL_64_BITS CONST64(-1)
106
107 // For DLL loading/load error detection
108 // Values of PE COFF
109 #define IMAGE_FILE_PTR_TO_SIGNATURE 0x3c
110 #define IMAGE_FILE_SIGNATURE_LENGTH 4
111
112 static HANDLE main_process;
113 static HANDLE main_thread;
114 static int main_thread_id;
115
116 static FILETIME process_creation_time;
117 static FILETIME process_exit_time;
118 static FILETIME process_user_time;
119 static FILETIME process_kernel_time;
120
121 #ifdef _M_AMD64
122 #define __CPU__ amd64
123 #else
124 #define __CPU__ i486
125 #endif
126
127 // save DLL module handle, used by GetModuleFileName
128
129 HINSTANCE vm_lib_handle;
130
131 BOOL WINAPI DllMain(HINSTANCE hinst, DWORD reason, LPVOID reserved) {
132 switch (reason) {
133 case DLL_PROCESS_ATTACH:
134 vm_lib_handle = hinst;
135 if (ForceTimeHighResolution) {
136 timeBeginPeriod(1L);
137 }
138 WindowsDbgHelp::pre_initialize();
139 SymbolEngine::pre_initialize();
140 break;
141 case DLL_PROCESS_DETACH:
142 if (ForceTimeHighResolution) {
143 timeEndPeriod(1L);
144 }
145 break;
146 default:
147 break;
148 }
149 return true;
150 }
151
152 static inline double fileTimeAsDouble(FILETIME* time) {
153 const double high = (double) ((unsigned int) ~0);
154 const double split = 10000000.0;
155 double result = (time->dwLowDateTime / split) +
156 time->dwHighDateTime * (high/split);
157 return result;
158 }
159
160 // Implementation of os
161
162 bool os::unsetenv(const char* name) {
163 assert(name != NULL, "Null pointer");
164 return (SetEnvironmentVariable(name, NULL) == TRUE);
165 }
166
167 // No setuid programs under Windows.
168 bool os::have_special_privileges() {
169 return false;
170 }
171
172
173 // This method is a periodic task to check for misbehaving JNI applications
174 // under CheckJNI, we can add any periodic checks here.
175 // For Windows at the moment does nothing
176 void os::run_periodic_checks() {
177 return;
178 }
179
180 // previous UnhandledExceptionFilter, if there is one
181 static LPTOP_LEVEL_EXCEPTION_FILTER prev_uef_handler = NULL;
182
183 LONG WINAPI Handle_FLT_Exception(struct _EXCEPTION_POINTERS* exceptionInfo);
184
185 void os::init_system_properties_values() {
186 // sysclasspath, java_home, dll_dir
187 {
188 char *home_path;
189 char *dll_path;
190 char *pslash;
191 char *bin = "\\bin";
192 char home_dir[MAX_PATH + 1];
193 char *alt_home_dir = ::getenv("_ALT_JAVA_HOME_DIR");
194
195 if (alt_home_dir != NULL) {
196 strncpy(home_dir, alt_home_dir, MAX_PATH + 1);
197 home_dir[MAX_PATH] = '\0';
198 } else {
199 os::jvm_path(home_dir, sizeof(home_dir));
200 // Found the full path to jvm.dll.
201 // Now cut the path to <java_home>/jre if we can.
202 *(strrchr(home_dir, '\\')) = '\0'; // get rid of \jvm.dll
203 pslash = strrchr(home_dir, '\\');
204 if (pslash != NULL) {
205 *pslash = '\0'; // get rid of \{client|server}
206 pslash = strrchr(home_dir, '\\');
207 if (pslash != NULL) {
208 *pslash = '\0'; // get rid of \bin
209 }
210 }
211 }
212
213 home_path = NEW_C_HEAP_ARRAY(char, strlen(home_dir) + 1, mtInternal);
214 if (home_path == NULL) {
215 return;
216 }
217 strcpy(home_path, home_dir);
218 Arguments::set_java_home(home_path);
219 FREE_C_HEAP_ARRAY(char, home_path);
220
221 dll_path = NEW_C_HEAP_ARRAY(char, strlen(home_dir) + strlen(bin) + 1,
222 mtInternal);
223 if (dll_path == NULL) {
224 return;
225 }
226 strcpy(dll_path, home_dir);
227 strcat(dll_path, bin);
228 Arguments::set_dll_dir(dll_path);
229 FREE_C_HEAP_ARRAY(char, dll_path);
230
231 if (!set_boot_path('\\', ';')) {
232 return;
233 }
234 }
235
236 // library_path
237 #define EXT_DIR "\\lib\\ext"
238 #define BIN_DIR "\\bin"
239 #define PACKAGE_DIR "\\Sun\\Java"
240 {
241 // Win32 library search order (See the documentation for LoadLibrary):
242 //
243 // 1. The directory from which application is loaded.
244 // 2. The system wide Java Extensions directory (Java only)
245 // 3. System directory (GetSystemDirectory)
246 // 4. Windows directory (GetWindowsDirectory)
247 // 5. The PATH environment variable
248 // 6. The current directory
249
250 char *library_path;
251 char tmp[MAX_PATH];
252 char *path_str = ::getenv("PATH");
253
254 library_path = NEW_C_HEAP_ARRAY(char, MAX_PATH * 5 + sizeof(PACKAGE_DIR) +
255 sizeof(BIN_DIR) + (path_str ? strlen(path_str) : 0) + 10, mtInternal);
256
257 library_path[0] = '\0';
258
259 GetModuleFileName(NULL, tmp, sizeof(tmp));
260 *(strrchr(tmp, '\\')) = '\0';
261 strcat(library_path, tmp);
262
263 GetWindowsDirectory(tmp, sizeof(tmp));
264 strcat(library_path, ";");
265 strcat(library_path, tmp);
266 strcat(library_path, PACKAGE_DIR BIN_DIR);
267
268 GetSystemDirectory(tmp, sizeof(tmp));
269 strcat(library_path, ";");
270 strcat(library_path, tmp);
271
272 GetWindowsDirectory(tmp, sizeof(tmp));
273 strcat(library_path, ";");
274 strcat(library_path, tmp);
275
276 if (path_str) {
277 strcat(library_path, ";");
278 strcat(library_path, path_str);
279 }
280
281 strcat(library_path, ";.");
282
283 Arguments::set_library_path(library_path);
284 FREE_C_HEAP_ARRAY(char, library_path);
285 }
286
287 // Default extensions directory
288 {
289 char path[MAX_PATH];
290 char buf[2 * MAX_PATH + 2 * sizeof(EXT_DIR) + sizeof(PACKAGE_DIR) + 1];
291 GetWindowsDirectory(path, MAX_PATH);
292 sprintf(buf, "%s%s;%s%s%s", Arguments::get_java_home(), EXT_DIR,
293 path, PACKAGE_DIR, EXT_DIR);
294 Arguments::set_ext_dirs(buf);
295 }
296 #undef EXT_DIR
297 #undef BIN_DIR
298 #undef PACKAGE_DIR
299
300 #ifndef _WIN64
301 // set our UnhandledExceptionFilter and save any previous one
302 prev_uef_handler = SetUnhandledExceptionFilter(Handle_FLT_Exception);
303 #endif
304
305 // Done
306 return;
307 }
308
309 void os::breakpoint() {
310 DebugBreak();
311 }
312
313 // Invoked from the BREAKPOINT Macro
314 extern "C" void breakpoint() {
315 os::breakpoint();
316 }
317
318 // RtlCaptureStackBackTrace Windows API may not exist prior to Windows XP.
319 // So far, this method is only used by Native Memory Tracking, which is
320 // only supported on Windows XP or later.
321 //
322 int os::get_native_stack(address* stack, int frames, int toSkip) {
323 int captured = RtlCaptureStackBackTrace(toSkip + 1, frames, (PVOID*)stack, NULL);
324 for (int index = captured; index < frames; index ++) {
325 stack[index] = NULL;
326 }
327 return captured;
328 }
329
330
331 // os::current_stack_base()
332 //
333 // Returns the base of the stack, which is the stack's
334 // starting address. This function must be called
335 // while running on the stack of the thread being queried.
336
337 address os::current_stack_base() {
338 MEMORY_BASIC_INFORMATION minfo;
339 address stack_bottom;
340 size_t stack_size;
341
342 VirtualQuery(&minfo, &minfo, sizeof(minfo));
343 stack_bottom = (address)minfo.AllocationBase;
344 stack_size = minfo.RegionSize;
345
346 // Add up the sizes of all the regions with the same
347 // AllocationBase.
348 while (1) {
349 VirtualQuery(stack_bottom+stack_size, &minfo, sizeof(minfo));
350 if (stack_bottom == (address)minfo.AllocationBase) {
351 stack_size += minfo.RegionSize;
352 } else {
353 break;
354 }
355 }
356 return stack_bottom + stack_size;
357 }
358
359 size_t os::current_stack_size() {
360 size_t sz;
361 MEMORY_BASIC_INFORMATION minfo;
362 VirtualQuery(&minfo, &minfo, sizeof(minfo));
363 sz = (size_t)os::current_stack_base() - (size_t)minfo.AllocationBase;
364 return sz;
365 }
366
367 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
368 const struct tm* time_struct_ptr = localtime(clock);
369 if (time_struct_ptr != NULL) {
370 *res = *time_struct_ptr;
371 return res;
372 }
373 return NULL;
374 }
375
376 struct tm* os::gmtime_pd(const time_t* clock, struct tm* res) {
377 const struct tm* time_struct_ptr = gmtime(clock);
378 if (time_struct_ptr != NULL) {
379 *res = *time_struct_ptr;
380 return res;
381 }
382 return NULL;
383 }
384
385 LONG WINAPI topLevelExceptionFilter(struct _EXCEPTION_POINTERS* exceptionInfo);
386
387 // Thread start routine for all newly created threads
388 static unsigned __stdcall thread_native_entry(Thread* thread) {
389 // Try to randomize the cache line index of hot stack frames.
390 // This helps when threads of the same stack traces evict each other's
391 // cache lines. The threads can be either from the same JVM instance, or
392 // from different JVM instances. The benefit is especially true for
393 // processors with hyperthreading technology.
394 static int counter = 0;
395 int pid = os::current_process_id();
396 _alloca(((pid ^ counter++) & 7) * 128);
397
398 thread->initialize_thread_current();
399
400 OSThread* osthr = thread->osthread();
401 assert(osthr->get_state() == RUNNABLE, "invalid os thread state");
402
403 if (UseNUMA) {
404 int lgrp_id = os::numa_get_group_id();
405 if (lgrp_id != -1) {
406 thread->set_lgrp_id(lgrp_id);
407 }
408 }
409
410 // Diagnostic code to investigate JDK-6573254
411 int res = 30115; // non-java thread
412 if (thread->is_Java_thread()) {
413 res = 20115; // java thread
414 }
415
416 log_info(os, thread)("Thread is alive (tid: " UINTX_FORMAT ").", os::current_thread_id());
417
418 // Install a win32 structured exception handler around every thread created
419 // by VM, so VM can generate error dump when an exception occurred in non-
420 // Java thread (e.g. VM thread).
421 __try {
422 thread->run();
423 } __except(topLevelExceptionFilter(
424 (_EXCEPTION_POINTERS*)_exception_info())) {
425 // Nothing to do.
426 }
427
428 log_info(os, thread)("Thread finished (tid: " UINTX_FORMAT ").", os::current_thread_id());
429
430 // One less thread is executing
431 // When the VMThread gets here, the main thread may have already exited
432 // which frees the CodeHeap containing the Atomic::add code
433 if (thread != VMThread::vm_thread() && VMThread::vm_thread() != NULL) {
434 Atomic::dec(&os::win32::_os_thread_count);
435 }
436
437 // If a thread has not deleted itself ("delete this") as part of its
438 // termination sequence, we have to ensure thread-local-storage is
439 // cleared before we actually terminate. No threads should ever be
440 // deleted asynchronously with respect to their termination.
441 if (Thread::current_or_null_safe() != NULL) {
442 assert(Thread::current_or_null_safe() == thread, "current thread is wrong");
443 thread->clear_thread_current();
444 }
445
446 // Thread must not return from exit_process_or_thread(), but if it does,
447 // let it proceed to exit normally
448 return (unsigned)os::win32::exit_process_or_thread(os::win32::EPT_THREAD, res);
449 }
450
451 static OSThread* create_os_thread(Thread* thread, HANDLE thread_handle,
452 int thread_id) {
453 // Allocate the OSThread object
454 OSThread* osthread = new OSThread(NULL, NULL);
455 if (osthread == NULL) return NULL;
456
457 // Initialize support for Java interrupts
458 HANDLE interrupt_event = CreateEvent(NULL, true, false, NULL);
459 if (interrupt_event == NULL) {
460 delete osthread;
461 return NULL;
462 }
463 osthread->set_interrupt_event(interrupt_event);
464
465 // Store info on the Win32 thread into the OSThread
466 osthread->set_thread_handle(thread_handle);
467 osthread->set_thread_id(thread_id);
468
469 if (UseNUMA) {
470 int lgrp_id = os::numa_get_group_id();
471 if (lgrp_id != -1) {
472 thread->set_lgrp_id(lgrp_id);
473 }
474 }
475
476 // Initial thread state is INITIALIZED, not SUSPENDED
477 osthread->set_state(INITIALIZED);
478
479 return osthread;
480 }
481
482
483 bool os::create_attached_thread(JavaThread* thread) {
484 #ifdef ASSERT
485 thread->verify_not_published();
486 #endif
487 HANDLE thread_h;
488 if (!DuplicateHandle(main_process, GetCurrentThread(), GetCurrentProcess(),
489 &thread_h, THREAD_ALL_ACCESS, false, 0)) {
490 fatal("DuplicateHandle failed\n");
491 }
492 OSThread* osthread = create_os_thread(thread, thread_h,
493 (int)current_thread_id());
494 if (osthread == NULL) {
495 return false;
496 }
497
498 // Initial thread state is RUNNABLE
499 osthread->set_state(RUNNABLE);
500
501 thread->set_osthread(osthread);
502
503 log_info(os, thread)("Thread attached (tid: " UINTX_FORMAT ").",
504 os::current_thread_id());
505
506 return true;
507 }
508
509 bool os::create_main_thread(JavaThread* thread) {
510 #ifdef ASSERT
511 thread->verify_not_published();
512 #endif
513 if (_starting_thread == NULL) {
514 _starting_thread = create_os_thread(thread, main_thread, main_thread_id);
515 if (_starting_thread == NULL) {
516 return false;
517 }
518 }
519
520 // The primordial thread is runnable from the start)
521 _starting_thread->set_state(RUNNABLE);
522
523 thread->set_osthread(_starting_thread);
524 return true;
525 }
526
527 // Helper function to trace _beginthreadex attributes,
528 // similar to os::Posix::describe_pthread_attr()
529 static char* describe_beginthreadex_attributes(char* buf, size_t buflen,
530 size_t stacksize, unsigned initflag) {
531 stringStream ss(buf, buflen);
532 if (stacksize == 0) {
533 ss.print("stacksize: default, ");
534 } else {
535 ss.print("stacksize: " SIZE_FORMAT "k, ", stacksize / 1024);
536 }
537 ss.print("flags: ");
538 #define PRINT_FLAG(f) if (initflag & f) ss.print( #f " ");
539 #define ALL(X) \
540 X(CREATE_SUSPENDED) \
541 X(STACK_SIZE_PARAM_IS_A_RESERVATION)
542 ALL(PRINT_FLAG)
543 #undef ALL
544 #undef PRINT_FLAG
545 return buf;
546 }
547
548 // Allocate and initialize a new OSThread
549 bool os::create_thread(Thread* thread, ThreadType thr_type,
550 size_t stack_size) {
551 unsigned thread_id;
552
553 // Allocate the OSThread object
554 OSThread* osthread = new OSThread(NULL, NULL);
555 if (osthread == NULL) {
556 return false;
557 }
558
559 // Initialize support for Java interrupts
560 HANDLE interrupt_event = CreateEvent(NULL, true, false, NULL);
561 if (interrupt_event == NULL) {
562 delete osthread;
563 return NULL;
564 }
565 osthread->set_interrupt_event(interrupt_event);
566 osthread->set_interrupted(false);
567
568 thread->set_osthread(osthread);
569
570 if (stack_size == 0) {
571 switch (thr_type) {
572 case os::java_thread:
573 // Java threads use ThreadStackSize which default value can be changed with the flag -Xss
574 if (JavaThread::stack_size_at_create() > 0) {
575 stack_size = JavaThread::stack_size_at_create();
576 }
577 break;
578 case os::compiler_thread:
579 if (CompilerThreadStackSize > 0) {
580 stack_size = (size_t)(CompilerThreadStackSize * K);
581 break;
582 } // else fall through:
583 // use VMThreadStackSize if CompilerThreadStackSize is not defined
584 case os::vm_thread:
585 case os::pgc_thread:
586 case os::cgc_thread:
587 case os::watcher_thread:
588 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K);
589 break;
590 }
591 }
592
593 // Create the Win32 thread
594 //
595 // Contrary to what MSDN document says, "stack_size" in _beginthreadex()
596 // does not specify stack size. Instead, it specifies the size of
597 // initially committed space. The stack size is determined by
598 // PE header in the executable. If the committed "stack_size" is larger
599 // than default value in the PE header, the stack is rounded up to the
600 // nearest multiple of 1MB. For example if the launcher has default
601 // stack size of 320k, specifying any size less than 320k does not
602 // affect the actual stack size at all, it only affects the initial
603 // commitment. On the other hand, specifying 'stack_size' larger than
604 // default value may cause significant increase in memory usage, because
605 // not only the stack space will be rounded up to MB, but also the
606 // entire space is committed upfront.
607 //
608 // Finally Windows XP added a new flag 'STACK_SIZE_PARAM_IS_A_RESERVATION'
609 // for CreateThread() that can treat 'stack_size' as stack size. However we
610 // are not supposed to call CreateThread() directly according to MSDN
611 // document because JVM uses C runtime library. The good news is that the
612 // flag appears to work with _beginthredex() as well.
613
614 const unsigned initflag = CREATE_SUSPENDED | STACK_SIZE_PARAM_IS_A_RESERVATION;
615 HANDLE thread_handle =
616 (HANDLE)_beginthreadex(NULL,
617 (unsigned)stack_size,
618 (unsigned (__stdcall *)(void*)) thread_native_entry,
619 thread,
620 initflag,
621 &thread_id);
622
623 char buf[64];
624 if (thread_handle != NULL) {
625 log_info(os, thread)("Thread started (tid: %u, attributes: %s)",
626 thread_id, describe_beginthreadex_attributes(buf, sizeof(buf), stack_size, initflag));
627 } else {
628 log_warning(os, thread)("Failed to start thread - _beginthreadex failed (%s) for attributes: %s.",
629 os::errno_name(errno), describe_beginthreadex_attributes(buf, sizeof(buf), stack_size, initflag));
630 }
631
632 if (thread_handle == NULL) {
633 // Need to clean up stuff we've allocated so far
634 CloseHandle(osthread->interrupt_event());
635 thread->set_osthread(NULL);
636 delete osthread;
637 return NULL;
638 }
639
640 Atomic::inc(&os::win32::_os_thread_count);
641
642 // Store info on the Win32 thread into the OSThread
643 osthread->set_thread_handle(thread_handle);
644 osthread->set_thread_id(thread_id);
645
646 // Initial thread state is INITIALIZED, not SUSPENDED
647 osthread->set_state(INITIALIZED);
648
649 // The thread is returned suspended (in state INITIALIZED), and is started higher up in the call chain
650 return true;
651 }
652
653
654 // Free Win32 resources related to the OSThread
655 void os::free_thread(OSThread* osthread) {
656 assert(osthread != NULL, "osthread not set");
657
658 // We are told to free resources of the argument thread,
659 // but we can only really operate on the current thread.
660 assert(Thread::current()->osthread() == osthread,
661 "os::free_thread but not current thread");
662
663 CloseHandle(osthread->thread_handle());
664 CloseHandle(osthread->interrupt_event());
665 delete osthread;
666 }
667
668 static jlong first_filetime;
669 static jlong initial_performance_count;
670 static jlong performance_frequency;
671
672
673 jlong as_long(LARGE_INTEGER x) {
674 jlong result = 0; // initialization to avoid warning
675 set_high(&result, x.HighPart);
676 set_low(&result, x.LowPart);
677 return result;
678 }
679
680
681 jlong os::elapsed_counter() {
682 LARGE_INTEGER count;
683 QueryPerformanceCounter(&count);
684 return as_long(count) - initial_performance_count;
685 }
686
687
688 jlong os::elapsed_frequency() {
689 return performance_frequency;
690 }
691
692
693 julong os::available_memory() {
694 return win32::available_memory();
695 }
696
697 julong os::win32::available_memory() {
698 // Use GlobalMemoryStatusEx() because GlobalMemoryStatus() may return incorrect
699 // value if total memory is larger than 4GB
700 MEMORYSTATUSEX ms;
701 ms.dwLength = sizeof(ms);
702 GlobalMemoryStatusEx(&ms);
703
704 return (julong)ms.ullAvailPhys;
705 }
706
707 julong os::physical_memory() {
708 return win32::physical_memory();
709 }
710
711 bool os::has_allocatable_memory_limit(julong* limit) {
712 MEMORYSTATUSEX ms;
713 ms.dwLength = sizeof(ms);
714 GlobalMemoryStatusEx(&ms);
715 #ifdef _LP64
716 *limit = (julong)ms.ullAvailVirtual;
717 return true;
718 #else
719 // Limit to 1400m because of the 2gb address space wall
720 *limit = MIN2((julong)1400*M, (julong)ms.ullAvailVirtual);
721 return true;
722 #endif
723 }
724
725 int os::active_processor_count() {
726 DWORD_PTR lpProcessAffinityMask = 0;
727 DWORD_PTR lpSystemAffinityMask = 0;
728 int proc_count = processor_count();
729 if (proc_count <= sizeof(UINT_PTR) * BitsPerByte &&
730 GetProcessAffinityMask(GetCurrentProcess(), &lpProcessAffinityMask, &lpSystemAffinityMask)) {
731 // Nof active processors is number of bits in process affinity mask
732 int bitcount = 0;
733 while (lpProcessAffinityMask != 0) {
734 lpProcessAffinityMask = lpProcessAffinityMask & (lpProcessAffinityMask-1);
735 bitcount++;
736 }
737 return bitcount;
738 } else {
739 return proc_count;
740 }
741 }
742
743 void os::set_native_thread_name(const char *name) {
744
745 // See: http://msdn.microsoft.com/en-us/library/xcb2z8hs.aspx
746 //
747 // Note that unfortunately this only works if the process
748 // is already attached to a debugger; debugger must observe
749 // the exception below to show the correct name.
750
751 // If there is no debugger attached skip raising the exception
752 if (!IsDebuggerPresent()) {
753 return;
754 }
755
756 const DWORD MS_VC_EXCEPTION = 0x406D1388;
757 struct {
758 DWORD dwType; // must be 0x1000
759 LPCSTR szName; // pointer to name (in user addr space)
760 DWORD dwThreadID; // thread ID (-1=caller thread)
761 DWORD dwFlags; // reserved for future use, must be zero
762 } info;
763
764 info.dwType = 0x1000;
765 info.szName = name;
766 info.dwThreadID = -1;
767 info.dwFlags = 0;
768
769 __try {
770 RaiseException (MS_VC_EXCEPTION, 0, sizeof(info)/sizeof(DWORD), (const ULONG_PTR*)&info );
771 } __except(EXCEPTION_EXECUTE_HANDLER) {}
772 }
773
774 bool os::distribute_processes(uint length, uint* distribution) {
775 // Not yet implemented.
776 return false;
777 }
778
779 bool os::bind_to_processor(uint processor_id) {
780 // Not yet implemented.
781 return false;
782 }
783
784 void os::win32::initialize_performance_counter() {
785 LARGE_INTEGER count;
786 QueryPerformanceFrequency(&count);
787 performance_frequency = as_long(count);
788 QueryPerformanceCounter(&count);
789 initial_performance_count = as_long(count);
790 }
791
792
793 double os::elapsedTime() {
794 return (double) elapsed_counter() / (double) elapsed_frequency();
795 }
796
797
798 // Windows format:
799 // The FILETIME structure is a 64-bit value representing the number of 100-nanosecond intervals since January 1, 1601.
800 // Java format:
801 // Java standards require the number of milliseconds since 1/1/1970
802
803 // Constant offset - calculated using offset()
804 static jlong _offset = 116444736000000000;
805 // Fake time counter for reproducible results when debugging
806 static jlong fake_time = 0;
807
808 #ifdef ASSERT
809 // Just to be safe, recalculate the offset in debug mode
810 static jlong _calculated_offset = 0;
811 static int _has_calculated_offset = 0;
812
813 jlong offset() {
814 if (_has_calculated_offset) return _calculated_offset;
815 SYSTEMTIME java_origin;
816 java_origin.wYear = 1970;
817 java_origin.wMonth = 1;
818 java_origin.wDayOfWeek = 0; // ignored
819 java_origin.wDay = 1;
820 java_origin.wHour = 0;
821 java_origin.wMinute = 0;
822 java_origin.wSecond = 0;
823 java_origin.wMilliseconds = 0;
824 FILETIME jot;
825 if (!SystemTimeToFileTime(&java_origin, &jot)) {
826 fatal("Error = %d\nWindows error", GetLastError());
827 }
828 _calculated_offset = jlong_from(jot.dwHighDateTime, jot.dwLowDateTime);
829 _has_calculated_offset = 1;
830 assert(_calculated_offset == _offset, "Calculated and constant time offsets must be equal");
831 return _calculated_offset;
832 }
833 #else
834 jlong offset() {
835 return _offset;
836 }
837 #endif
838
839 jlong windows_to_java_time(FILETIME wt) {
840 jlong a = jlong_from(wt.dwHighDateTime, wt.dwLowDateTime);
841 return (a - offset()) / 10000;
842 }
843
844 // Returns time ticks in (10th of micro seconds)
845 jlong windows_to_time_ticks(FILETIME wt) {
846 jlong a = jlong_from(wt.dwHighDateTime, wt.dwLowDateTime);
847 return (a - offset());
848 }
849
850 FILETIME java_to_windows_time(jlong l) {
851 jlong a = (l * 10000) + offset();
852 FILETIME result;
853 result.dwHighDateTime = high(a);
854 result.dwLowDateTime = low(a);
855 return result;
856 }
857
858 bool os::supports_vtime() { return true; }
859 bool os::enable_vtime() { return false; }
860 bool os::vtime_enabled() { return false; }
861
862 double os::elapsedVTime() {
863 FILETIME created;
864 FILETIME exited;
865 FILETIME kernel;
866 FILETIME user;
867 if (GetThreadTimes(GetCurrentThread(), &created, &exited, &kernel, &user) != 0) {
868 // the resolution of windows_to_java_time() should be sufficient (ms)
869 return (double) (windows_to_java_time(kernel) + windows_to_java_time(user)) / MILLIUNITS;
870 } else {
871 return elapsedTime();
872 }
873 }
874
875 jlong os::javaTimeMillis() {
876 if (UseFakeTimers) {
877 return fake_time++;
878 } else {
879 FILETIME wt;
880 GetSystemTimeAsFileTime(&wt);
881 return windows_to_java_time(wt);
882 }
883 }
884
885 void os::javaTimeSystemUTC(jlong &seconds, jlong &nanos) {
886 FILETIME wt;
887 GetSystemTimeAsFileTime(&wt);
888 jlong ticks = windows_to_time_ticks(wt); // 10th of micros
889 jlong secs = jlong(ticks / 10000000); // 10000 * 1000
890 seconds = secs;
891 nanos = jlong(ticks - (secs*10000000)) * 100;
892 }
893
894 jlong os::javaTimeNanos() {
895 LARGE_INTEGER current_count;
896 QueryPerformanceCounter(¤t_count);
897 double current = as_long(current_count);
898 double freq = performance_frequency;
899 jlong time = (jlong)((current/freq) * NANOSECS_PER_SEC);
900 return time;
901 }
902
903 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
904 jlong freq = performance_frequency;
905 if (freq < NANOSECS_PER_SEC) {
906 // the performance counter is 64 bits and we will
907 // be multiplying it -- so no wrap in 64 bits
908 info_ptr->max_value = ALL_64_BITS;
909 } else if (freq > NANOSECS_PER_SEC) {
910 // use the max value the counter can reach to
911 // determine the max value which could be returned
912 julong max_counter = (julong)ALL_64_BITS;
913 info_ptr->max_value = (jlong)(max_counter / (freq / NANOSECS_PER_SEC));
914 } else {
915 // the performance counter is 64 bits and we will
916 // be using it directly -- so no wrap in 64 bits
917 info_ptr->max_value = ALL_64_BITS;
918 }
919
920 // using a counter, so no skipping
921 info_ptr->may_skip_backward = false;
922 info_ptr->may_skip_forward = false;
923
924 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
925 }
926
927 char* os::local_time_string(char *buf, size_t buflen) {
928 SYSTEMTIME st;
929 GetLocalTime(&st);
930 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
931 st.wYear, st.wMonth, st.wDay, st.wHour, st.wMinute, st.wSecond);
932 return buf;
933 }
934
935 bool os::getTimesSecs(double* process_real_time,
936 double* process_user_time,
937 double* process_system_time) {
938 HANDLE h_process = GetCurrentProcess();
939 FILETIME create_time, exit_time, kernel_time, user_time;
940 BOOL result = GetProcessTimes(h_process,
941 &create_time,
942 &exit_time,
943 &kernel_time,
944 &user_time);
945 if (result != 0) {
946 FILETIME wt;
947 GetSystemTimeAsFileTime(&wt);
948 jlong rtc_millis = windows_to_java_time(wt);
949 *process_real_time = ((double) rtc_millis) / ((double) MILLIUNITS);
950 *process_user_time =
951 (double) jlong_from(user_time.dwHighDateTime, user_time.dwLowDateTime) / (10 * MICROUNITS);
952 *process_system_time =
953 (double) jlong_from(kernel_time.dwHighDateTime, kernel_time.dwLowDateTime) / (10 * MICROUNITS);
954 return true;
955 } else {
956 return false;
957 }
958 }
959
960 void os::shutdown() {
961 // allow PerfMemory to attempt cleanup of any persistent resources
962 perfMemory_exit();
963
964 // flush buffered output, finish log files
965 ostream_abort();
966
967 // Check for abort hook
968 abort_hook_t abort_hook = Arguments::abort_hook();
969 if (abort_hook != NULL) {
970 abort_hook();
971 }
972 }
973
974
975 static BOOL (WINAPI *_MiniDumpWriteDump)(HANDLE, DWORD, HANDLE, MINIDUMP_TYPE,
976 PMINIDUMP_EXCEPTION_INFORMATION,
977 PMINIDUMP_USER_STREAM_INFORMATION,
978 PMINIDUMP_CALLBACK_INFORMATION);
979
980 static HANDLE dumpFile = NULL;
981
982 // Check if dump file can be created.
983 void os::check_dump_limit(char* buffer, size_t buffsz) {
984 bool status = true;
985 if (!FLAG_IS_DEFAULT(CreateCoredumpOnCrash) && !CreateCoredumpOnCrash) {
986 jio_snprintf(buffer, buffsz, "CreateCoredumpOnCrash is disabled from command line");
987 status = false;
988 }
989
990 #ifndef ASSERT
991 if (!os::win32::is_windows_server() && FLAG_IS_DEFAULT(CreateCoredumpOnCrash)) {
992 jio_snprintf(buffer, buffsz, "Minidumps are not enabled by default on client versions of Windows");
993 status = false;
994 }
995 #endif
996
997 if (status) {
998 const char* cwd = get_current_directory(NULL, 0);
999 int pid = current_process_id();
1000 if (cwd != NULL) {
1001 jio_snprintf(buffer, buffsz, "%s\\hs_err_pid%u.mdmp", cwd, pid);
1002 } else {
1003 jio_snprintf(buffer, buffsz, ".\\hs_err_pid%u.mdmp", pid);
1004 }
1005
1006 if (dumpFile == NULL &&
1007 (dumpFile = CreateFile(buffer, GENERIC_WRITE, 0, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL))
1008 == INVALID_HANDLE_VALUE) {
1009 jio_snprintf(buffer, buffsz, "Failed to create minidump file (0x%x).", GetLastError());
1010 status = false;
1011 }
1012 }
1013 VMError::record_coredump_status(buffer, status);
1014 }
1015
1016 void os::abort(bool dump_core, void* siginfo, const void* context) {
1017 EXCEPTION_POINTERS ep;
1018 MINIDUMP_EXCEPTION_INFORMATION mei;
1019 MINIDUMP_EXCEPTION_INFORMATION* pmei;
1020
1021 HANDLE hProcess = GetCurrentProcess();
1022 DWORD processId = GetCurrentProcessId();
1023 MINIDUMP_TYPE dumpType;
1024
1025 shutdown();
1026 if (!dump_core || dumpFile == NULL) {
1027 if (dumpFile != NULL) {
1028 CloseHandle(dumpFile);
1029 }
1030 win32::exit_process_or_thread(win32::EPT_PROCESS, 1);
1031 }
1032
1033 dumpType = (MINIDUMP_TYPE)(MiniDumpWithFullMemory | MiniDumpWithHandleData |
1034 MiniDumpWithFullMemoryInfo | MiniDumpWithThreadInfo | MiniDumpWithUnloadedModules);
1035
1036 if (siginfo != NULL && context != NULL) {
1037 ep.ContextRecord = (PCONTEXT) context;
1038 ep.ExceptionRecord = (PEXCEPTION_RECORD) siginfo;
1039
1040 mei.ThreadId = GetCurrentThreadId();
1041 mei.ExceptionPointers = &ep;
1042 pmei = &mei;
1043 } else {
1044 pmei = NULL;
1045 }
1046
1047 // Older versions of dbghelp.dll (the one shipped with Win2003 for example) may not support all
1048 // the dump types we really want. If first call fails, lets fall back to just use MiniDumpWithFullMemory then.
1049 if (!WindowsDbgHelp::miniDumpWriteDump(hProcess, processId, dumpFile, dumpType, pmei, NULL, NULL) &&
1050 !WindowsDbgHelp::miniDumpWriteDump(hProcess, processId, dumpFile, (MINIDUMP_TYPE)MiniDumpWithFullMemory, pmei, NULL, NULL)) {
1051 jio_fprintf(stderr, "Call to MiniDumpWriteDump() failed (Error 0x%x)\n", GetLastError());
1052 }
1053 CloseHandle(dumpFile);
1054 win32::exit_process_or_thread(win32::EPT_PROCESS, 1);
1055 }
1056
1057 // Die immediately, no exit hook, no abort hook, no cleanup.
1058 void os::die() {
1059 win32::exit_process_or_thread(win32::EPT_PROCESS_DIE, -1);
1060 }
1061
1062 // Directory routines copied from src/win32/native/java/io/dirent_md.c
1063 // * dirent_md.c 1.15 00/02/02
1064 //
1065 // The declarations for DIR and struct dirent are in jvm_win32.h.
1066
1067 // Caller must have already run dirname through JVM_NativePath, which removes
1068 // duplicate slashes and converts all instances of '/' into '\\'.
1069
1070 DIR * os::opendir(const char *dirname) {
1071 assert(dirname != NULL, "just checking"); // hotspot change
1072 DIR *dirp = (DIR *)malloc(sizeof(DIR), mtInternal);
1073 DWORD fattr; // hotspot change
1074 char alt_dirname[4] = { 0, 0, 0, 0 };
1075
1076 if (dirp == 0) {
1077 errno = ENOMEM;
1078 return 0;
1079 }
1080
1081 // Win32 accepts "\" in its POSIX stat(), but refuses to treat it
1082 // as a directory in FindFirstFile(). We detect this case here and
1083 // prepend the current drive name.
1084 //
1085 if (dirname[1] == '\0' && dirname[0] == '\\') {
1086 alt_dirname[0] = _getdrive() + 'A' - 1;
1087 alt_dirname[1] = ':';
1088 alt_dirname[2] = '\\';
1089 alt_dirname[3] = '\0';
1090 dirname = alt_dirname;
1091 }
1092
1093 dirp->path = (char *)malloc(strlen(dirname) + 5, mtInternal);
1094 if (dirp->path == 0) {
1095 free(dirp);
1096 errno = ENOMEM;
1097 return 0;
1098 }
1099 strcpy(dirp->path, dirname);
1100
1101 fattr = GetFileAttributes(dirp->path);
1102 if (fattr == 0xffffffff) {
1103 free(dirp->path);
1104 free(dirp);
1105 errno = ENOENT;
1106 return 0;
1107 } else if ((fattr & FILE_ATTRIBUTE_DIRECTORY) == 0) {
1108 free(dirp->path);
1109 free(dirp);
1110 errno = ENOTDIR;
1111 return 0;
1112 }
1113
1114 // Append "*.*", or possibly "\\*.*", to path
1115 if (dirp->path[1] == ':' &&
1116 (dirp->path[2] == '\0' ||
1117 (dirp->path[2] == '\\' && dirp->path[3] == '\0'))) {
1118 // No '\\' needed for cases like "Z:" or "Z:\"
1119 strcat(dirp->path, "*.*");
1120 } else {
1121 strcat(dirp->path, "\\*.*");
1122 }
1123
1124 dirp->handle = FindFirstFile(dirp->path, &dirp->find_data);
1125 if (dirp->handle == INVALID_HANDLE_VALUE) {
1126 if (GetLastError() != ERROR_FILE_NOT_FOUND) {
1127 free(dirp->path);
1128 free(dirp);
1129 errno = EACCES;
1130 return 0;
1131 }
1132 }
1133 return dirp;
1134 }
1135
1136 // parameter dbuf unused on Windows
1137 struct dirent * os::readdir(DIR *dirp, dirent *dbuf) {
1138 assert(dirp != NULL, "just checking"); // hotspot change
1139 if (dirp->handle == INVALID_HANDLE_VALUE) {
1140 return 0;
1141 }
1142
1143 strcpy(dirp->dirent.d_name, dirp->find_data.cFileName);
1144
1145 if (!FindNextFile(dirp->handle, &dirp->find_data)) {
1146 if (GetLastError() == ERROR_INVALID_HANDLE) {
1147 errno = EBADF;
1148 return 0;
1149 }
1150 FindClose(dirp->handle);
1151 dirp->handle = INVALID_HANDLE_VALUE;
1152 }
1153
1154 return &dirp->dirent;
1155 }
1156
1157 int os::closedir(DIR *dirp) {
1158 assert(dirp != NULL, "just checking"); // hotspot change
1159 if (dirp->handle != INVALID_HANDLE_VALUE) {
1160 if (!FindClose(dirp->handle)) {
1161 errno = EBADF;
1162 return -1;
1163 }
1164 dirp->handle = INVALID_HANDLE_VALUE;
1165 }
1166 free(dirp->path);
1167 free(dirp);
1168 return 0;
1169 }
1170
1171 // This must be hard coded because it's the system's temporary
1172 // directory not the java application's temp directory, ala java.io.tmpdir.
1173 const char* os::get_temp_directory() {
1174 static char path_buf[MAX_PATH];
1175 if (GetTempPath(MAX_PATH, path_buf) > 0) {
1176 return path_buf;
1177 } else {
1178 path_buf[0] = '\0';
1179 return path_buf;
1180 }
1181 }
1182
1183 // Needs to be in os specific directory because windows requires another
1184 // header file <direct.h>
1185 const char* os::get_current_directory(char *buf, size_t buflen) {
1186 int n = static_cast<int>(buflen);
1187 if (buflen > INT_MAX) n = INT_MAX;
1188 return _getcwd(buf, n);
1189 }
1190
1191 //-----------------------------------------------------------
1192 // Helper functions for fatal error handler
1193 #ifdef _WIN64
1194 // Helper routine which returns true if address in
1195 // within the NTDLL address space.
1196 //
1197 static bool _addr_in_ntdll(address addr) {
1198 HMODULE hmod;
1199 MODULEINFO minfo;
1200
1201 hmod = GetModuleHandle("NTDLL.DLL");
1202 if (hmod == NULL) return false;
1203 if (!GetModuleInformation(GetCurrentProcess(), hmod,
1204 &minfo, sizeof(MODULEINFO))) {
1205 return false;
1206 }
1207
1208 if ((addr >= minfo.lpBaseOfDll) &&
1209 (addr < (address)((uintptr_t)minfo.lpBaseOfDll + (uintptr_t)minfo.SizeOfImage))) {
1210 return true;
1211 } else {
1212 return false;
1213 }
1214 }
1215 #endif
1216
1217 struct _modinfo {
1218 address addr;
1219 char* full_path; // point to a char buffer
1220 int buflen; // size of the buffer
1221 address base_addr;
1222 };
1223
1224 static int _locate_module_by_addr(const char * mod_fname, address base_addr,
1225 address top_address, void * param) {
1226 struct _modinfo *pmod = (struct _modinfo *)param;
1227 if (!pmod) return -1;
1228
1229 if (base_addr <= pmod->addr &&
1230 top_address > pmod->addr) {
1231 // if a buffer is provided, copy path name to the buffer
1232 if (pmod->full_path) {
1233 jio_snprintf(pmod->full_path, pmod->buflen, "%s", mod_fname);
1234 }
1235 pmod->base_addr = base_addr;
1236 return 1;
1237 }
1238 return 0;
1239 }
1240
1241 bool os::dll_address_to_library_name(address addr, char* buf,
1242 int buflen, int* offset) {
1243 // buf is not optional, but offset is optional
1244 assert(buf != NULL, "sanity check");
1245
1246 // NOTE: the reason we don't use SymGetModuleInfo() is it doesn't always
1247 // return the full path to the DLL file, sometimes it returns path
1248 // to the corresponding PDB file (debug info); sometimes it only
1249 // returns partial path, which makes life painful.
1250
1251 struct _modinfo mi;
1252 mi.addr = addr;
1253 mi.full_path = buf;
1254 mi.buflen = buflen;
1255 if (get_loaded_modules_info(_locate_module_by_addr, (void *)&mi)) {
1256 // buf already contains path name
1257 if (offset) *offset = addr - mi.base_addr;
1258 return true;
1259 }
1260
1261 buf[0] = '\0';
1262 if (offset) *offset = -1;
1263 return false;
1264 }
1265
1266 bool os::dll_address_to_function_name(address addr, char *buf,
1267 int buflen, int *offset,
1268 bool demangle) {
1269 // buf is not optional, but offset is optional
1270 assert(buf != NULL, "sanity check");
1271
1272 if (Decoder::decode(addr, buf, buflen, offset, demangle)) {
1273 return true;
1274 }
1275 if (offset != NULL) *offset = -1;
1276 buf[0] = '\0';
1277 return false;
1278 }
1279
1280 // save the start and end address of jvm.dll into param[0] and param[1]
1281 static int _locate_jvm_dll(const char* mod_fname, address base_addr,
1282 address top_address, void * param) {
1283 if (!param) return -1;
1284
1285 if (base_addr <= (address)_locate_jvm_dll &&
1286 top_address > (address)_locate_jvm_dll) {
1287 ((address*)param)[0] = base_addr;
1288 ((address*)param)[1] = top_address;
1289 return 1;
1290 }
1291 return 0;
1292 }
1293
1294 address vm_lib_location[2]; // start and end address of jvm.dll
1295
1296 // check if addr is inside jvm.dll
1297 bool os::address_is_in_vm(address addr) {
1298 if (!vm_lib_location[0] || !vm_lib_location[1]) {
1299 if (!get_loaded_modules_info(_locate_jvm_dll, (void *)vm_lib_location)) {
1300 assert(false, "Can't find jvm module.");
1301 return false;
1302 }
1303 }
1304
1305 return (vm_lib_location[0] <= addr) && (addr < vm_lib_location[1]);
1306 }
1307
1308 // print module info; param is outputStream*
1309 static int _print_module(const char* fname, address base_address,
1310 address top_address, void* param) {
1311 if (!param) return -1;
1312
1313 outputStream* st = (outputStream*)param;
1314
1315 st->print(PTR_FORMAT " - " PTR_FORMAT " \t%s\n", base_address, top_address, fname);
1316 return 0;
1317 }
1318
1319 // Loads .dll/.so and
1320 // in case of error it checks if .dll/.so was built for the
1321 // same architecture as Hotspot is running on
1322 void * os::dll_load(const char *name, char *ebuf, int ebuflen) {
1323 void * result = LoadLibrary(name);
1324 if (result != NULL) {
1325 // Recalculate pdb search path if a DLL was loaded successfully.
1326 SymbolEngine::recalc_search_path();
1327 return result;
1328 }
1329
1330 DWORD errcode = GetLastError();
1331 if (errcode == ERROR_MOD_NOT_FOUND) {
1332 strncpy(ebuf, "Can't find dependent libraries", ebuflen - 1);
1333 ebuf[ebuflen - 1] = '\0';
1334 return NULL;
1335 }
1336
1337 // Parsing dll below
1338 // If we can read dll-info and find that dll was built
1339 // for an architecture other than Hotspot is running in
1340 // - then print to buffer "DLL was built for a different architecture"
1341 // else call os::lasterror to obtain system error message
1342
1343 // Read system error message into ebuf
1344 // It may or may not be overwritten below (in the for loop and just above)
1345 lasterror(ebuf, (size_t) ebuflen);
1346 ebuf[ebuflen - 1] = '\0';
1347 int fd = ::open(name, O_RDONLY | O_BINARY, 0);
1348 if (fd < 0) {
1349 return NULL;
1350 }
1351
1352 uint32_t signature_offset;
1353 uint16_t lib_arch = 0;
1354 bool failed_to_get_lib_arch =
1355 ( // Go to position 3c in the dll
1356 (os::seek_to_file_offset(fd, IMAGE_FILE_PTR_TO_SIGNATURE) < 0)
1357 ||
1358 // Read location of signature
1359 (sizeof(signature_offset) !=
1360 (os::read(fd, (void*)&signature_offset, sizeof(signature_offset))))
1361 ||
1362 // Go to COFF File Header in dll
1363 // that is located after "signature" (4 bytes long)
1364 (os::seek_to_file_offset(fd,
1365 signature_offset + IMAGE_FILE_SIGNATURE_LENGTH) < 0)
1366 ||
1367 // Read field that contains code of architecture
1368 // that dll was built for
1369 (sizeof(lib_arch) != (os::read(fd, (void*)&lib_arch, sizeof(lib_arch))))
1370 );
1371
1372 ::close(fd);
1373 if (failed_to_get_lib_arch) {
1374 // file i/o error - report os::lasterror(...) msg
1375 return NULL;
1376 }
1377
1378 typedef struct {
1379 uint16_t arch_code;
1380 char* arch_name;
1381 } arch_t;
1382
1383 static const arch_t arch_array[] = {
1384 {IMAGE_FILE_MACHINE_I386, (char*)"IA 32"},
1385 {IMAGE_FILE_MACHINE_AMD64, (char*)"AMD 64"}
1386 };
1387 #if (defined _M_AMD64)
1388 static const uint16_t running_arch = IMAGE_FILE_MACHINE_AMD64;
1389 #elif (defined _M_IX86)
1390 static const uint16_t running_arch = IMAGE_FILE_MACHINE_I386;
1391 #else
1392 #error Method os::dll_load requires that one of following \
1393 is defined :_M_AMD64 or _M_IX86
1394 #endif
1395
1396
1397 // Obtain a string for printf operation
1398 // lib_arch_str shall contain string what platform this .dll was built for
1399 // running_arch_str shall string contain what platform Hotspot was built for
1400 char *running_arch_str = NULL, *lib_arch_str = NULL;
1401 for (unsigned int i = 0; i < ARRAY_SIZE(arch_array); i++) {
1402 if (lib_arch == arch_array[i].arch_code) {
1403 lib_arch_str = arch_array[i].arch_name;
1404 }
1405 if (running_arch == arch_array[i].arch_code) {
1406 running_arch_str = arch_array[i].arch_name;
1407 }
1408 }
1409
1410 assert(running_arch_str,
1411 "Didn't find running architecture code in arch_array");
1412
1413 // If the architecture is right
1414 // but some other error took place - report os::lasterror(...) msg
1415 if (lib_arch == running_arch) {
1416 return NULL;
1417 }
1418
1419 if (lib_arch_str != NULL) {
1420 ::_snprintf(ebuf, ebuflen - 1,
1421 "Can't load %s-bit .dll on a %s-bit platform",
1422 lib_arch_str, running_arch_str);
1423 } else {
1424 // don't know what architecture this dll was build for
1425 ::_snprintf(ebuf, ebuflen - 1,
1426 "Can't load this .dll (machine code=0x%x) on a %s-bit platform",
1427 lib_arch, running_arch_str);
1428 }
1429
1430 return NULL;
1431 }
1432
1433 void os::print_dll_info(outputStream *st) {
1434 st->print_cr("Dynamic libraries:");
1435 get_loaded_modules_info(_print_module, (void *)st);
1436 }
1437
1438 int os::get_loaded_modules_info(os::LoadedModulesCallbackFunc callback, void *param) {
1439 HANDLE hProcess;
1440
1441 # define MAX_NUM_MODULES 128
1442 HMODULE modules[MAX_NUM_MODULES];
1443 static char filename[MAX_PATH];
1444 int result = 0;
1445
1446 int pid = os::current_process_id();
1447 hProcess = OpenProcess(PROCESS_QUERY_INFORMATION | PROCESS_VM_READ,
1448 FALSE, pid);
1449 if (hProcess == NULL) return 0;
1450
1451 DWORD size_needed;
1452 if (!EnumProcessModules(hProcess, modules, sizeof(modules), &size_needed)) {
1453 CloseHandle(hProcess);
1454 return 0;
1455 }
1456
1457 // number of modules that are currently loaded
1458 int num_modules = size_needed / sizeof(HMODULE);
1459
1460 for (int i = 0; i < MIN2(num_modules, MAX_NUM_MODULES); i++) {
1461 // Get Full pathname:
1462 if (!GetModuleFileNameEx(hProcess, modules[i], filename, sizeof(filename))) {
1463 filename[0] = '\0';
1464 }
1465
1466 MODULEINFO modinfo;
1467 if (!GetModuleInformation(hProcess, modules[i], &modinfo, sizeof(modinfo))) {
1468 modinfo.lpBaseOfDll = NULL;
1469 modinfo.SizeOfImage = 0;
1470 }
1471
1472 // Invoke callback function
1473 result = callback(filename, (address)modinfo.lpBaseOfDll,
1474 (address)((u8)modinfo.lpBaseOfDll + (u8)modinfo.SizeOfImage), param);
1475 if (result) break;
1476 }
1477
1478 CloseHandle(hProcess);
1479 return result;
1480 }
1481
1482 bool os::get_host_name(char* buf, size_t buflen) {
1483 DWORD size = (DWORD)buflen;
1484 return (GetComputerNameEx(ComputerNameDnsHostname, buf, &size) == TRUE);
1485 }
1486
1487 void os::get_summary_os_info(char* buf, size_t buflen) {
1488 stringStream sst(buf, buflen);
1489 os::win32::print_windows_version(&sst);
1490 // chop off newline character
1491 char* nl = strchr(buf, '\n');
1492 if (nl != NULL) *nl = '\0';
1493 }
1494
1495 int os::log_vsnprintf(char* buf, size_t len, const char* fmt, va_list args) {
1496 int ret = vsnprintf(buf, len, fmt, args);
1497 // Get the correct buffer size if buf is too small
1498 if (ret < 0) {
1499 return _vscprintf(fmt, args);
1500 }
1501 return ret;
1502 }
1503
1504 static inline time_t get_mtime(const char* filename) {
1505 struct stat st;
1506 int ret = os::stat(filename, &st);
1507 assert(ret == 0, "failed to stat() file '%s': %s", filename, strerror(errno));
1508 return st.st_mtime;
1509 }
1510
1511 int os::compare_file_modified_times(const char* file1, const char* file2) {
1512 time_t t1 = get_mtime(file1);
1513 time_t t2 = get_mtime(file2);
1514 return t1 - t2;
1515 }
1516
1517 void os::print_os_info_brief(outputStream* st) {
1518 os::print_os_info(st);
1519 }
1520
1521 void os::print_os_info(outputStream* st) {
1522 #ifdef ASSERT
1523 char buffer[1024];
1524 st->print("HostName: ");
1525 if (get_host_name(buffer, sizeof(buffer))) {
1526 st->print("%s ", buffer);
1527 } else {
1528 st->print("N/A ");
1529 }
1530 #endif
1531 st->print("OS:");
1532 os::win32::print_windows_version(st);
1533 }
1534
1535 void os::win32::print_windows_version(outputStream* st) {
1536 OSVERSIONINFOEX osvi;
1537 VS_FIXEDFILEINFO *file_info;
1538 TCHAR kernel32_path[MAX_PATH];
1539 UINT len, ret;
1540
1541 // Use the GetVersionEx information to see if we're on a server or
1542 // workstation edition of Windows. Starting with Windows 8.1 we can't
1543 // trust the OS version information returned by this API.
1544 ZeroMemory(&osvi, sizeof(OSVERSIONINFOEX));
1545 osvi.dwOSVersionInfoSize = sizeof(OSVERSIONINFOEX);
1546 if (!GetVersionEx((OSVERSIONINFO *)&osvi)) {
1547 st->print_cr("Call to GetVersionEx failed");
1548 return;
1549 }
1550 bool is_workstation = (osvi.wProductType == VER_NT_WORKSTATION);
1551
1552 // Get the full path to \Windows\System32\kernel32.dll and use that for
1553 // determining what version of Windows we're running on.
1554 len = MAX_PATH - (UINT)strlen("\\kernel32.dll") - 1;
1555 ret = GetSystemDirectory(kernel32_path, len);
1556 if (ret == 0 || ret > len) {
1557 st->print_cr("Call to GetSystemDirectory failed");
1558 return;
1559 }
1560 strncat(kernel32_path, "\\kernel32.dll", MAX_PATH - ret);
1561
1562 DWORD version_size = GetFileVersionInfoSize(kernel32_path, NULL);
1563 if (version_size == 0) {
1564 st->print_cr("Call to GetFileVersionInfoSize failed");
1565 return;
1566 }
1567
1568 LPTSTR version_info = (LPTSTR)os::malloc(version_size, mtInternal);
1569 if (version_info == NULL) {
1570 st->print_cr("Failed to allocate version_info");
1571 return;
1572 }
1573
1574 if (!GetFileVersionInfo(kernel32_path, NULL, version_size, version_info)) {
1575 os::free(version_info);
1576 st->print_cr("Call to GetFileVersionInfo failed");
1577 return;
1578 }
1579
1580 if (!VerQueryValue(version_info, TEXT("\\"), (LPVOID*)&file_info, &len)) {
1581 os::free(version_info);
1582 st->print_cr("Call to VerQueryValue failed");
1583 return;
1584 }
1585
1586 int major_version = HIWORD(file_info->dwProductVersionMS);
1587 int minor_version = LOWORD(file_info->dwProductVersionMS);
1588 int build_number = HIWORD(file_info->dwProductVersionLS);
1589 int build_minor = LOWORD(file_info->dwProductVersionLS);
1590 int os_vers = major_version * 1000 + minor_version;
1591 os::free(version_info);
1592
1593 st->print(" Windows ");
1594 switch (os_vers) {
1595
1596 case 6000:
1597 if (is_workstation) {
1598 st->print("Vista");
1599 } else {
1600 st->print("Server 2008");
1601 }
1602 break;
1603
1604 case 6001:
1605 if (is_workstation) {
1606 st->print("7");
1607 } else {
1608 st->print("Server 2008 R2");
1609 }
1610 break;
1611
1612 case 6002:
1613 if (is_workstation) {
1614 st->print("8");
1615 } else {
1616 st->print("Server 2012");
1617 }
1618 break;
1619
1620 case 6003:
1621 if (is_workstation) {
1622 st->print("8.1");
1623 } else {
1624 st->print("Server 2012 R2");
1625 }
1626 break;
1627
1628 case 10000:
1629 if (is_workstation) {
1630 st->print("10");
1631 } else {
1632 st->print("Server 2016");
1633 }
1634 break;
1635
1636 default:
1637 // Unrecognized windows, print out its major and minor versions
1638 st->print("%d.%d", major_version, minor_version);
1639 break;
1640 }
1641
1642 // Retrieve SYSTEM_INFO from GetNativeSystemInfo call so that we could
1643 // find out whether we are running on 64 bit processor or not
1644 SYSTEM_INFO si;
1645 ZeroMemory(&si, sizeof(SYSTEM_INFO));
1646 GetNativeSystemInfo(&si);
1647 if (si.wProcessorArchitecture == PROCESSOR_ARCHITECTURE_AMD64) {
1648 st->print(" , 64 bit");
1649 }
1650
1651 st->print(" Build %d", build_number);
1652 st->print(" (%d.%d.%d.%d)", major_version, minor_version, build_number, build_minor);
1653 st->cr();
1654 }
1655
1656 void os::pd_print_cpu_info(outputStream* st, char* buf, size_t buflen) {
1657 // Nothing to do for now.
1658 }
1659
1660 void os::get_summary_cpu_info(char* buf, size_t buflen) {
1661 HKEY key;
1662 DWORD status = RegOpenKey(HKEY_LOCAL_MACHINE,
1663 "HARDWARE\\DESCRIPTION\\System\\CentralProcessor\\0", &key);
1664 if (status == ERROR_SUCCESS) {
1665 DWORD size = (DWORD)buflen;
1666 status = RegQueryValueEx(key, "ProcessorNameString", NULL, NULL, (byte*)buf, &size);
1667 if (status != ERROR_SUCCESS) {
1668 strncpy(buf, "## __CPU__", buflen);
1669 }
1670 RegCloseKey(key);
1671 } else {
1672 // Put generic cpu info to return
1673 strncpy(buf, "## __CPU__", buflen);
1674 }
1675 }
1676
1677 void os::print_memory_info(outputStream* st) {
1678 st->print("Memory:");
1679 st->print(" %dk page", os::vm_page_size()>>10);
1680
1681 // Use GlobalMemoryStatusEx() because GlobalMemoryStatus() may return incorrect
1682 // value if total memory is larger than 4GB
1683 MEMORYSTATUSEX ms;
1684 ms.dwLength = sizeof(ms);
1685 GlobalMemoryStatusEx(&ms);
1686
1687 st->print(", physical %uk", os::physical_memory() >> 10);
1688 st->print("(%uk free)", os::available_memory() >> 10);
1689
1690 st->print(", swap %uk", ms.ullTotalPageFile >> 10);
1691 st->print("(%uk free)", ms.ullAvailPageFile >> 10);
1692 st->cr();
1693 }
1694
1695 void os::print_siginfo(outputStream *st, const void* siginfo) {
1696 const EXCEPTION_RECORD* const er = (EXCEPTION_RECORD*)siginfo;
1697 st->print("siginfo:");
1698
1699 char tmp[64];
1700 if (os::exception_name(er->ExceptionCode, tmp, sizeof(tmp)) == NULL) {
1701 strcpy(tmp, "EXCEPTION_??");
1702 }
1703 st->print(" %s (0x%x)", tmp, er->ExceptionCode);
1704
1705 if ((er->ExceptionCode == EXCEPTION_ACCESS_VIOLATION ||
1706 er->ExceptionCode == EXCEPTION_IN_PAGE_ERROR) &&
1707 er->NumberParameters >= 2) {
1708 switch (er->ExceptionInformation[0]) {
1709 case 0: st->print(", reading address"); break;
1710 case 1: st->print(", writing address"); break;
1711 case 8: st->print(", data execution prevention violation at address"); break;
1712 default: st->print(", ExceptionInformation=" INTPTR_FORMAT,
1713 er->ExceptionInformation[0]);
1714 }
1715 st->print(" " INTPTR_FORMAT, er->ExceptionInformation[1]);
1716 } else {
1717 int num = er->NumberParameters;
1718 if (num > 0) {
1719 st->print(", ExceptionInformation=");
1720 for (int i = 0; i < num; i++) {
1721 st->print(INTPTR_FORMAT " ", er->ExceptionInformation[i]);
1722 }
1723 }
1724 }
1725 st->cr();
1726 }
1727
1728 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1729 // do nothing
1730 }
1731
1732 static char saved_jvm_path[MAX_PATH] = {0};
1733
1734 // Find the full path to the current module, jvm.dll
1735 void os::jvm_path(char *buf, jint buflen) {
1736 // Error checking.
1737 if (buflen < MAX_PATH) {
1738 assert(false, "must use a large-enough buffer");
1739 buf[0] = '\0';
1740 return;
1741 }
1742 // Lazy resolve the path to current module.
1743 if (saved_jvm_path[0] != 0) {
1744 strcpy(buf, saved_jvm_path);
1745 return;
1746 }
1747
1748 buf[0] = '\0';
1749 if (Arguments::sun_java_launcher_is_altjvm()) {
1750 // Support for the java launcher's '-XXaltjvm=<path>' option. Check
1751 // for a JAVA_HOME environment variable and fix up the path so it
1752 // looks like jvm.dll is installed there (append a fake suffix
1753 // hotspot/jvm.dll).
1754 char* java_home_var = ::getenv("JAVA_HOME");
1755 if (java_home_var != NULL && java_home_var[0] != 0 &&
1756 strlen(java_home_var) < (size_t)buflen) {
1757 strncpy(buf, java_home_var, buflen);
1758
1759 // determine if this is a legacy image or modules image
1760 // modules image doesn't have "jre" subdirectory
1761 size_t len = strlen(buf);
1762 char* jrebin_p = buf + len;
1763 jio_snprintf(jrebin_p, buflen-len, "\\jre\\bin\\");
1764 if (0 != _access(buf, 0)) {
1765 jio_snprintf(jrebin_p, buflen-len, "\\bin\\");
1766 }
1767 len = strlen(buf);
1768 jio_snprintf(buf + len, buflen-len, "hotspot\\jvm.dll");
1769 }
1770 }
1771
1772 if (buf[0] == '\0') {
1773 GetModuleFileName(vm_lib_handle, buf, buflen);
1774 }
1775 strncpy(saved_jvm_path, buf, MAX_PATH);
1776 saved_jvm_path[MAX_PATH - 1] = '\0';
1777 }
1778
1779
1780 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1781 #ifndef _WIN64
1782 st->print("_");
1783 #endif
1784 }
1785
1786
1787 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1788 #ifndef _WIN64
1789 st->print("@%d", args_size * sizeof(int));
1790 #endif
1791 }
1792
1793 // This method is a copy of JDK's sysGetLastErrorString
1794 // from src/windows/hpi/src/system_md.c
1795
1796 size_t os::lasterror(char* buf, size_t len) {
1797 DWORD errval;
1798
1799 if ((errval = GetLastError()) != 0) {
1800 // DOS error
1801 size_t n = (size_t)FormatMessage(
1802 FORMAT_MESSAGE_FROM_SYSTEM|FORMAT_MESSAGE_IGNORE_INSERTS,
1803 NULL,
1804 errval,
1805 0,
1806 buf,
1807 (DWORD)len,
1808 NULL);
1809 if (n > 3) {
1810 // Drop final '.', CR, LF
1811 if (buf[n - 1] == '\n') n--;
1812 if (buf[n - 1] == '\r') n--;
1813 if (buf[n - 1] == '.') n--;
1814 buf[n] = '\0';
1815 }
1816 return n;
1817 }
1818
1819 if (errno != 0) {
1820 // C runtime error that has no corresponding DOS error code
1821 const char* s = os::strerror(errno);
1822 size_t n = strlen(s);
1823 if (n >= len) n = len - 1;
1824 strncpy(buf, s, n);
1825 buf[n] = '\0';
1826 return n;
1827 }
1828
1829 return 0;
1830 }
1831
1832 int os::get_last_error() {
1833 DWORD error = GetLastError();
1834 if (error == 0) {
1835 error = errno;
1836 }
1837 return (int)error;
1838 }
1839
1840 WindowsSemaphore::WindowsSemaphore(uint value) {
1841 _semaphore = ::CreateSemaphore(NULL, value, LONG_MAX, NULL);
1842
1843 guarantee(_semaphore != NULL, "CreateSemaphore failed with error code: %lu", GetLastError());
1844 }
1845
1846 WindowsSemaphore::~WindowsSemaphore() {
1847 ::CloseHandle(_semaphore);
1848 }
1849
1850 void WindowsSemaphore::signal(uint count) {
1851 if (count > 0) {
1852 BOOL ret = ::ReleaseSemaphore(_semaphore, count, NULL);
1853
1854 assert(ret != 0, "ReleaseSemaphore failed with error code: %lu", GetLastError());
1855 }
1856 }
1857
1858 void WindowsSemaphore::wait() {
1859 DWORD ret = ::WaitForSingleObject(_semaphore, INFINITE);
1860 assert(ret != WAIT_FAILED, "WaitForSingleObject failed with error code: %lu", GetLastError());
1861 assert(ret == WAIT_OBJECT_0, "WaitForSingleObject failed with return value: %lu", ret);
1862 }
1863
1864 bool WindowsSemaphore::trywait() {
1865 DWORD ret = ::WaitForSingleObject(_semaphore, 0);
1866 assert(ret != WAIT_FAILED, "WaitForSingleObject failed with error code: %lu", GetLastError());
1867 return ret == WAIT_OBJECT_0;
1868 }
1869
1870 // sun.misc.Signal
1871 // NOTE that this is a workaround for an apparent kernel bug where if
1872 // a signal handler for SIGBREAK is installed then that signal handler
1873 // takes priority over the console control handler for CTRL_CLOSE_EVENT.
1874 // See bug 4416763.
1875 static void (*sigbreakHandler)(int) = NULL;
1876
1877 static void UserHandler(int sig, void *siginfo, void *context) {
1878 os::signal_notify(sig);
1879 // We need to reinstate the signal handler each time...
1880 os::signal(sig, (void*)UserHandler);
1881 }
1882
1883 void* os::user_handler() {
1884 return (void*) UserHandler;
1885 }
1886
1887 void* os::signal(int signal_number, void* handler) {
1888 if ((signal_number == SIGBREAK) && (!ReduceSignalUsage)) {
1889 void (*oldHandler)(int) = sigbreakHandler;
1890 sigbreakHandler = (void (*)(int)) handler;
1891 return (void*) oldHandler;
1892 } else {
1893 return (void*)::signal(signal_number, (void (*)(int))handler);
1894 }
1895 }
1896
1897 void os::signal_raise(int signal_number) {
1898 raise(signal_number);
1899 }
1900
1901 // The Win32 C runtime library maps all console control events other than ^C
1902 // into SIGBREAK, which makes it impossible to distinguish ^BREAK from close,
1903 // logoff, and shutdown events. We therefore install our own console handler
1904 // that raises SIGTERM for the latter cases.
1905 //
1906 static BOOL WINAPI consoleHandler(DWORD event) {
1907 switch (event) {
1908 case CTRL_C_EVENT:
1909 if (VMError::is_error_reported()) {
1910 // Ctrl-C is pressed during error reporting, likely because the error
1911 // handler fails to abort. Let VM die immediately.
1912 os::die();
1913 }
1914
1915 os::signal_raise(SIGINT);
1916 return TRUE;
1917 break;
1918 case CTRL_BREAK_EVENT:
1919 if (sigbreakHandler != NULL) {
1920 (*sigbreakHandler)(SIGBREAK);
1921 }
1922 return TRUE;
1923 break;
1924 case CTRL_LOGOFF_EVENT: {
1925 // Don't terminate JVM if it is running in a non-interactive session,
1926 // such as a service process.
1927 USEROBJECTFLAGS flags;
1928 HANDLE handle = GetProcessWindowStation();
1929 if (handle != NULL &&
1930 GetUserObjectInformation(handle, UOI_FLAGS, &flags,
1931 sizeof(USEROBJECTFLAGS), NULL)) {
1932 // If it is a non-interactive session, let next handler to deal
1933 // with it.
1934 if ((flags.dwFlags & WSF_VISIBLE) == 0) {
1935 return FALSE;
1936 }
1937 }
1938 }
1939 case CTRL_CLOSE_EVENT:
1940 case CTRL_SHUTDOWN_EVENT:
1941 os::signal_raise(SIGTERM);
1942 return TRUE;
1943 break;
1944 default:
1945 break;
1946 }
1947 return FALSE;
1948 }
1949
1950 // The following code is moved from os.cpp for making this
1951 // code platform specific, which it is by its very nature.
1952
1953 // Return maximum OS signal used + 1 for internal use only
1954 // Used as exit signal for signal_thread
1955 int os::sigexitnum_pd() {
1956 return NSIG;
1957 }
1958
1959 // a counter for each possible signal value, including signal_thread exit signal
1960 static volatile jint pending_signals[NSIG+1] = { 0 };
1961 static HANDLE sig_sem = NULL;
1962
1963 void os::signal_init_pd() {
1964 // Initialize signal structures
1965 memset((void*)pending_signals, 0, sizeof(pending_signals));
1966
1967 sig_sem = ::CreateSemaphore(NULL, 0, NSIG+1, NULL);
1968
1969 // Programs embedding the VM do not want it to attempt to receive
1970 // events like CTRL_LOGOFF_EVENT, which are used to implement the
1971 // shutdown hooks mechanism introduced in 1.3. For example, when
1972 // the VM is run as part of a Windows NT service (i.e., a servlet
1973 // engine in a web server), the correct behavior is for any console
1974 // control handler to return FALSE, not TRUE, because the OS's
1975 // "final" handler for such events allows the process to continue if
1976 // it is a service (while terminating it if it is not a service).
1977 // To make this behavior uniform and the mechanism simpler, we
1978 // completely disable the VM's usage of these console events if -Xrs
1979 // (=ReduceSignalUsage) is specified. This means, for example, that
1980 // the CTRL-BREAK thread dump mechanism is also disabled in this
1981 // case. See bugs 4323062, 4345157, and related bugs.
1982
1983 if (!ReduceSignalUsage) {
1984 // Add a CTRL-C handler
1985 SetConsoleCtrlHandler(consoleHandler, TRUE);
1986 }
1987 }
1988
1989 void os::signal_notify(int signal_number) {
1990 BOOL ret;
1991 if (sig_sem != NULL) {
1992 Atomic::inc(&pending_signals[signal_number]);
1993 ret = ::ReleaseSemaphore(sig_sem, 1, NULL);
1994 assert(ret != 0, "ReleaseSemaphore() failed");
1995 }
1996 }
1997
1998 static int check_pending_signals(bool wait_for_signal) {
1999 DWORD ret;
2000 while (true) {
2001 for (int i = 0; i < NSIG + 1; i++) {
2002 jint n = pending_signals[i];
2003 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
2004 return i;
2005 }
2006 }
2007 if (!wait_for_signal) {
2008 return -1;
2009 }
2010
2011 JavaThread *thread = JavaThread::current();
2012
2013 ThreadBlockInVM tbivm(thread);
2014
2015 bool threadIsSuspended;
2016 do {
2017 thread->set_suspend_equivalent();
2018 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
2019 ret = ::WaitForSingleObject(sig_sem, INFINITE);
2020 assert(ret == WAIT_OBJECT_0, "WaitForSingleObject() failed");
2021
2022 // were we externally suspended while we were waiting?
2023 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
2024 if (threadIsSuspended) {
2025 // The semaphore has been incremented, but while we were waiting
2026 // another thread suspended us. We don't want to continue running
2027 // while suspended because that would surprise the thread that
2028 // suspended us.
2029 ret = ::ReleaseSemaphore(sig_sem, 1, NULL);
2030 assert(ret != 0, "ReleaseSemaphore() failed");
2031
2032 thread->java_suspend_self();
2033 }
2034 } while (threadIsSuspended);
2035 }
2036 }
2037
2038 int os::signal_lookup() {
2039 return check_pending_signals(false);
2040 }
2041
2042 int os::signal_wait() {
2043 return check_pending_signals(true);
2044 }
2045
2046 // Implicit OS exception handling
2047
2048 LONG Handle_Exception(struct _EXCEPTION_POINTERS* exceptionInfo,
2049 address handler) {
2050 JavaThread* thread = (JavaThread*) Thread::current_or_null();
2051 // Save pc in thread
2052 #ifdef _M_AMD64
2053 // Do not blow up if no thread info available.
2054 if (thread) {
2055 thread->set_saved_exception_pc((address)(DWORD_PTR)exceptionInfo->ContextRecord->Rip);
2056 }
2057 // Set pc to handler
2058 exceptionInfo->ContextRecord->Rip = (DWORD64)handler;
2059 #else
2060 // Do not blow up if no thread info available.
2061 if (thread) {
2062 thread->set_saved_exception_pc((address)(DWORD_PTR)exceptionInfo->ContextRecord->Eip);
2063 }
2064 // Set pc to handler
2065 exceptionInfo->ContextRecord->Eip = (DWORD)(DWORD_PTR)handler;
2066 #endif
2067
2068 // Continue the execution
2069 return EXCEPTION_CONTINUE_EXECUTION;
2070 }
2071
2072
2073 // Used for PostMortemDump
2074 extern "C" void safepoints();
2075 extern "C" void find(int x);
2076 extern "C" void events();
2077
2078 // According to Windows API documentation, an illegal instruction sequence should generate
2079 // the 0xC000001C exception code. However, real world experience shows that occasionnaly
2080 // the execution of an illegal instruction can generate the exception code 0xC000001E. This
2081 // seems to be an undocumented feature of Win NT 4.0 (and probably other Windows systems).
2082
2083 #define EXCEPTION_ILLEGAL_INSTRUCTION_2 0xC000001E
2084
2085 // From "Execution Protection in the Windows Operating System" draft 0.35
2086 // Once a system header becomes available, the "real" define should be
2087 // included or copied here.
2088 #define EXCEPTION_INFO_EXEC_VIOLATION 0x08
2089
2090 // Windows Vista/2008 heap corruption check
2091 #define EXCEPTION_HEAP_CORRUPTION 0xC0000374
2092
2093 // All Visual C++ exceptions thrown from code generated by the Microsoft Visual
2094 // C++ compiler contain this error code. Because this is a compiler-generated
2095 // error, the code is not listed in the Win32 API header files.
2096 // The code is actually a cryptic mnemonic device, with the initial "E"
2097 // standing for "exception" and the final 3 bytes (0x6D7363) representing the
2098 // ASCII values of "msc".
2099
2100 #define EXCEPTION_UNCAUGHT_CXX_EXCEPTION 0xE06D7363
2101
2102 #define def_excpt(val) { #val, (val) }
2103
2104 static const struct { char* name; uint number; } exceptlabels[] = {
2105 def_excpt(EXCEPTION_ACCESS_VIOLATION),
2106 def_excpt(EXCEPTION_DATATYPE_MISALIGNMENT),
2107 def_excpt(EXCEPTION_BREAKPOINT),
2108 def_excpt(EXCEPTION_SINGLE_STEP),
2109 def_excpt(EXCEPTION_ARRAY_BOUNDS_EXCEEDED),
2110 def_excpt(EXCEPTION_FLT_DENORMAL_OPERAND),
2111 def_excpt(EXCEPTION_FLT_DIVIDE_BY_ZERO),
2112 def_excpt(EXCEPTION_FLT_INEXACT_RESULT),
2113 def_excpt(EXCEPTION_FLT_INVALID_OPERATION),
2114 def_excpt(EXCEPTION_FLT_OVERFLOW),
2115 def_excpt(EXCEPTION_FLT_STACK_CHECK),
2116 def_excpt(EXCEPTION_FLT_UNDERFLOW),
2117 def_excpt(EXCEPTION_INT_DIVIDE_BY_ZERO),
2118 def_excpt(EXCEPTION_INT_OVERFLOW),
2119 def_excpt(EXCEPTION_PRIV_INSTRUCTION),
2120 def_excpt(EXCEPTION_IN_PAGE_ERROR),
2121 def_excpt(EXCEPTION_ILLEGAL_INSTRUCTION),
2122 def_excpt(EXCEPTION_ILLEGAL_INSTRUCTION_2),
2123 def_excpt(EXCEPTION_NONCONTINUABLE_EXCEPTION),
2124 def_excpt(EXCEPTION_STACK_OVERFLOW),
2125 def_excpt(EXCEPTION_INVALID_DISPOSITION),
2126 def_excpt(EXCEPTION_GUARD_PAGE),
2127 def_excpt(EXCEPTION_INVALID_HANDLE),
2128 def_excpt(EXCEPTION_UNCAUGHT_CXX_EXCEPTION),
2129 def_excpt(EXCEPTION_HEAP_CORRUPTION)
2130 };
2131
2132 #undef def_excpt
2133
2134 const char* os::exception_name(int exception_code, char *buf, size_t size) {
2135 uint code = static_cast<uint>(exception_code);
2136 for (uint i = 0; i < ARRAY_SIZE(exceptlabels); ++i) {
2137 if (exceptlabels[i].number == code) {
2138 jio_snprintf(buf, size, "%s", exceptlabels[i].name);
2139 return buf;
2140 }
2141 }
2142
2143 return NULL;
2144 }
2145
2146 //-----------------------------------------------------------------------------
2147 LONG Handle_IDiv_Exception(struct _EXCEPTION_POINTERS* exceptionInfo) {
2148 // handle exception caused by idiv; should only happen for -MinInt/-1
2149 // (division by zero is handled explicitly)
2150 #ifdef _M_AMD64
2151 PCONTEXT ctx = exceptionInfo->ContextRecord;
2152 address pc = (address)ctx->Rip;
2153 assert(pc[0] >= Assembler::REX && pc[0] <= Assembler::REX_WRXB && pc[1] == 0xF7 || pc[0] == 0xF7, "not an idiv opcode");
2154 assert(pc[0] >= Assembler::REX && pc[0] <= Assembler::REX_WRXB && (pc[2] & ~0x7) == 0xF8 || (pc[1] & ~0x7) == 0xF8, "cannot handle non-register operands");
2155 if (pc[0] == 0xF7) {
2156 // set correct result values and continue after idiv instruction
2157 ctx->Rip = (DWORD64)pc + 2; // idiv reg, reg is 2 bytes
2158 } else {
2159 ctx->Rip = (DWORD64)pc + 3; // REX idiv reg, reg is 3 bytes
2160 }
2161 // Do not set ctx->Rax as it already contains the correct value (either 32 or 64 bit, depending on the operation)
2162 // this is the case because the exception only happens for -MinValue/-1 and -MinValue is always in rax because of the
2163 // idiv opcode (0xF7).
2164 ctx->Rdx = (DWORD)0; // remainder
2165 // Continue the execution
2166 #else
2167 PCONTEXT ctx = exceptionInfo->ContextRecord;
2168 address pc = (address)ctx->Eip;
2169 assert(pc[0] == 0xF7, "not an idiv opcode");
2170 assert((pc[1] & ~0x7) == 0xF8, "cannot handle non-register operands");
2171 assert(ctx->Eax == min_jint, "unexpected idiv exception");
2172 // set correct result values and continue after idiv instruction
2173 ctx->Eip = (DWORD)pc + 2; // idiv reg, reg is 2 bytes
2174 ctx->Eax = (DWORD)min_jint; // result
2175 ctx->Edx = (DWORD)0; // remainder
2176 // Continue the execution
2177 #endif
2178 return EXCEPTION_CONTINUE_EXECUTION;
2179 }
2180
2181 //-----------------------------------------------------------------------------
2182 LONG WINAPI Handle_FLT_Exception(struct _EXCEPTION_POINTERS* exceptionInfo) {
2183 PCONTEXT ctx = exceptionInfo->ContextRecord;
2184 #ifndef _WIN64
2185 // handle exception caused by native method modifying control word
2186 DWORD exception_code = exceptionInfo->ExceptionRecord->ExceptionCode;
2187
2188 switch (exception_code) {
2189 case EXCEPTION_FLT_DENORMAL_OPERAND:
2190 case EXCEPTION_FLT_DIVIDE_BY_ZERO:
2191 case EXCEPTION_FLT_INEXACT_RESULT:
2192 case EXCEPTION_FLT_INVALID_OPERATION:
2193 case EXCEPTION_FLT_OVERFLOW:
2194 case EXCEPTION_FLT_STACK_CHECK:
2195 case EXCEPTION_FLT_UNDERFLOW:
2196 jint fp_control_word = (* (jint*) StubRoutines::addr_fpu_cntrl_wrd_std());
2197 if (fp_control_word != ctx->FloatSave.ControlWord) {
2198 // Restore FPCW and mask out FLT exceptions
2199 ctx->FloatSave.ControlWord = fp_control_word | 0xffffffc0;
2200 // Mask out pending FLT exceptions
2201 ctx->FloatSave.StatusWord &= 0xffffff00;
2202 return EXCEPTION_CONTINUE_EXECUTION;
2203 }
2204 }
2205
2206 if (prev_uef_handler != NULL) {
2207 // We didn't handle this exception so pass it to the previous
2208 // UnhandledExceptionFilter.
2209 return (prev_uef_handler)(exceptionInfo);
2210 }
2211 #else // !_WIN64
2212 // On Windows, the mxcsr control bits are non-volatile across calls
2213 // See also CR 6192333
2214 //
2215 jint MxCsr = INITIAL_MXCSR;
2216 // we can't use StubRoutines::addr_mxcsr_std()
2217 // because in Win64 mxcsr is not saved there
2218 if (MxCsr != ctx->MxCsr) {
2219 ctx->MxCsr = MxCsr;
2220 return EXCEPTION_CONTINUE_EXECUTION;
2221 }
2222 #endif // !_WIN64
2223
2224 return EXCEPTION_CONTINUE_SEARCH;
2225 }
2226
2227 static inline void report_error(Thread* t, DWORD exception_code,
2228 address addr, void* siginfo, void* context) {
2229 VMError::report_and_die(t, exception_code, addr, siginfo, context);
2230
2231 // If UseOsErrorReporting, this will return here and save the error file
2232 // somewhere where we can find it in the minidump.
2233 }
2234
2235 bool os::win32::get_frame_at_stack_banging_point(JavaThread* thread,
2236 struct _EXCEPTION_POINTERS* exceptionInfo, address pc, frame* fr) {
2237 PEXCEPTION_RECORD exceptionRecord = exceptionInfo->ExceptionRecord;
2238 address addr = (address) exceptionRecord->ExceptionInformation[1];
2239 if (Interpreter::contains(pc)) {
2240 *fr = os::fetch_frame_from_context((void*)exceptionInfo->ContextRecord);
2241 if (!fr->is_first_java_frame()) {
2242 // get_frame_at_stack_banging_point() is only called when we
2243 // have well defined stacks so java_sender() calls do not need
2244 // to assert safe_for_sender() first.
2245 *fr = fr->java_sender();
2246 }
2247 } else {
2248 // more complex code with compiled code
2249 assert(!Interpreter::contains(pc), "Interpreted methods should have been handled above");
2250 CodeBlob* cb = CodeCache::find_blob(pc);
2251 if (cb == NULL || !cb->is_nmethod() || cb->is_frame_complete_at(pc)) {
2252 // Not sure where the pc points to, fallback to default
2253 // stack overflow handling
2254 return false;
2255 } else {
2256 *fr = os::fetch_frame_from_context((void*)exceptionInfo->ContextRecord);
2257 // in compiled code, the stack banging is performed just after the return pc
2258 // has been pushed on the stack
2259 *fr = frame(fr->sp() + 1, fr->fp(), (address)*(fr->sp()));
2260 if (!fr->is_java_frame()) {
2261 // See java_sender() comment above.
2262 *fr = fr->java_sender();
2263 }
2264 }
2265 }
2266 assert(fr->is_java_frame(), "Safety check");
2267 return true;
2268 }
2269
2270 //-----------------------------------------------------------------------------
2271 LONG WINAPI topLevelExceptionFilter(struct _EXCEPTION_POINTERS* exceptionInfo) {
2272 if (InterceptOSException) return EXCEPTION_CONTINUE_SEARCH;
2273 DWORD exception_code = exceptionInfo->ExceptionRecord->ExceptionCode;
2274 #ifdef _M_AMD64
2275 address pc = (address) exceptionInfo->ContextRecord->Rip;
2276 #else
2277 address pc = (address) exceptionInfo->ContextRecord->Eip;
2278 #endif
2279 Thread* t = Thread::current_or_null_safe();
2280
2281 // Handle SafeFetch32 and SafeFetchN exceptions.
2282 if (StubRoutines::is_safefetch_fault(pc)) {
2283 return Handle_Exception(exceptionInfo, StubRoutines::continuation_for_safefetch_fault(pc));
2284 }
2285
2286 #ifndef _WIN64
2287 // Execution protection violation - win32 running on AMD64 only
2288 // Handled first to avoid misdiagnosis as a "normal" access violation;
2289 // This is safe to do because we have a new/unique ExceptionInformation
2290 // code for this condition.
2291 if (exception_code == EXCEPTION_ACCESS_VIOLATION) {
2292 PEXCEPTION_RECORD exceptionRecord = exceptionInfo->ExceptionRecord;
2293 int exception_subcode = (int) exceptionRecord->ExceptionInformation[0];
2294 address addr = (address) exceptionRecord->ExceptionInformation[1];
2295
2296 if (exception_subcode == EXCEPTION_INFO_EXEC_VIOLATION) {
2297 int page_size = os::vm_page_size();
2298
2299 // Make sure the pc and the faulting address are sane.
2300 //
2301 // If an instruction spans a page boundary, and the page containing
2302 // the beginning of the instruction is executable but the following
2303 // page is not, the pc and the faulting address might be slightly
2304 // different - we still want to unguard the 2nd page in this case.
2305 //
2306 // 15 bytes seems to be a (very) safe value for max instruction size.
2307 bool pc_is_near_addr =
2308 (pointer_delta((void*) addr, (void*) pc, sizeof(char)) < 15);
2309 bool instr_spans_page_boundary =
2310 (align_down((intptr_t) pc ^ (intptr_t) addr,
2311 (intptr_t) page_size) > 0);
2312
2313 if (pc == addr || (pc_is_near_addr && instr_spans_page_boundary)) {
2314 static volatile address last_addr =
2315 (address) os::non_memory_address_word();
2316
2317 // In conservative mode, don't unguard unless the address is in the VM
2318 if (UnguardOnExecutionViolation > 0 && addr != last_addr &&
2319 (UnguardOnExecutionViolation > 1 || os::address_is_in_vm(addr))) {
2320
2321 // Set memory to RWX and retry
2322 address page_start = align_down(addr, page_size);
2323 bool res = os::protect_memory((char*) page_start, page_size,
2324 os::MEM_PROT_RWX);
2325
2326 log_debug(os)("Execution protection violation "
2327 "at " INTPTR_FORMAT
2328 ", unguarding " INTPTR_FORMAT ": %s", p2i(addr),
2329 p2i(page_start), (res ? "success" : os::strerror(errno)));
2330
2331 // Set last_addr so if we fault again at the same address, we don't
2332 // end up in an endless loop.
2333 //
2334 // There are two potential complications here. Two threads trapping
2335 // at the same address at the same time could cause one of the
2336 // threads to think it already unguarded, and abort the VM. Likely
2337 // very rare.
2338 //
2339 // The other race involves two threads alternately trapping at
2340 // different addresses and failing to unguard the page, resulting in
2341 // an endless loop. This condition is probably even more unlikely
2342 // than the first.
2343 //
2344 // Although both cases could be avoided by using locks or thread
2345 // local last_addr, these solutions are unnecessary complication:
2346 // this handler is a best-effort safety net, not a complete solution.
2347 // It is disabled by default and should only be used as a workaround
2348 // in case we missed any no-execute-unsafe VM code.
2349
2350 last_addr = addr;
2351
2352 return EXCEPTION_CONTINUE_EXECUTION;
2353 }
2354 }
2355
2356 // Last unguard failed or not unguarding
2357 tty->print_raw_cr("Execution protection violation");
2358 report_error(t, exception_code, addr, exceptionInfo->ExceptionRecord,
2359 exceptionInfo->ContextRecord);
2360 return EXCEPTION_CONTINUE_SEARCH;
2361 }
2362 }
2363 #endif // _WIN64
2364
2365 // Check to see if we caught the safepoint code in the
2366 // process of write protecting the memory serialization page.
2367 // It write enables the page immediately after protecting it
2368 // so just return.
2369 if (exception_code == EXCEPTION_ACCESS_VIOLATION) {
2370 if (t != NULL && t->is_Java_thread()) {
2371 JavaThread* thread = (JavaThread*) t;
2372 PEXCEPTION_RECORD exceptionRecord = exceptionInfo->ExceptionRecord;
2373 address addr = (address) exceptionRecord->ExceptionInformation[1];
2374 if (os::is_memory_serialize_page(thread, addr)) {
2375 // Block current thread until the memory serialize page permission restored.
2376 os::block_on_serialize_page_trap();
2377 return EXCEPTION_CONTINUE_EXECUTION;
2378 }
2379 }
2380 }
2381
2382 if ((exception_code == EXCEPTION_ACCESS_VIOLATION) &&
2383 VM_Version::is_cpuinfo_segv_addr(pc)) {
2384 // Verify that OS save/restore AVX registers.
2385 return Handle_Exception(exceptionInfo, VM_Version::cpuinfo_cont_addr());
2386 }
2387
2388 if (t != NULL && t->is_Java_thread()) {
2389 JavaThread* thread = (JavaThread*) t;
2390 bool in_java = thread->thread_state() == _thread_in_Java;
2391
2392 // Handle potential stack overflows up front.
2393 if (exception_code == EXCEPTION_STACK_OVERFLOW) {
2394 if (thread->stack_guards_enabled()) {
2395 if (in_java) {
2396 frame fr;
2397 PEXCEPTION_RECORD exceptionRecord = exceptionInfo->ExceptionRecord;
2398 address addr = (address) exceptionRecord->ExceptionInformation[1];
2399 if (os::win32::get_frame_at_stack_banging_point(thread, exceptionInfo, pc, &fr)) {
2400 assert(fr.is_java_frame(), "Must be a Java frame");
2401 SharedRuntime::look_for_reserved_stack_annotated_method(thread, fr);
2402 }
2403 }
2404 // Yellow zone violation. The o/s has unprotected the first yellow
2405 // zone page for us. Note: must call disable_stack_yellow_zone to
2406 // update the enabled status, even if the zone contains only one page.
2407 assert(thread->thread_state() != _thread_in_vm, "Undersized StackShadowPages");
2408 thread->disable_stack_yellow_reserved_zone();
2409 // If not in java code, return and hope for the best.
2410 return in_java
2411 ? Handle_Exception(exceptionInfo, SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW))
2412 : EXCEPTION_CONTINUE_EXECUTION;
2413 } else {
2414 // Fatal red zone violation.
2415 thread->disable_stack_red_zone();
2416 tty->print_raw_cr("An unrecoverable stack overflow has occurred.");
2417 report_error(t, exception_code, pc, exceptionInfo->ExceptionRecord,
2418 exceptionInfo->ContextRecord);
2419 return EXCEPTION_CONTINUE_SEARCH;
2420 }
2421 } else if (exception_code == EXCEPTION_ACCESS_VIOLATION) {
2422 // Either stack overflow or null pointer exception.
2423 if (in_java) {
2424 PEXCEPTION_RECORD exceptionRecord = exceptionInfo->ExceptionRecord;
2425 address addr = (address) exceptionRecord->ExceptionInformation[1];
2426 address stack_end = thread->stack_end();
2427 if (addr < stack_end && addr >= stack_end - os::vm_page_size()) {
2428 // Stack overflow.
2429 assert(!os::uses_stack_guard_pages(),
2430 "should be caught by red zone code above.");
2431 return Handle_Exception(exceptionInfo,
2432 SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW));
2433 }
2434 // Check for safepoint polling and implicit null
2435 // We only expect null pointers in the stubs (vtable)
2436 // the rest are checked explicitly now.
2437 CodeBlob* cb = CodeCache::find_blob(pc);
2438 if (cb != NULL) {
2439 if (os::is_poll_address(addr)) {
2440 address stub = SharedRuntime::get_poll_stub(pc);
2441 return Handle_Exception(exceptionInfo, stub);
2442 }
2443 }
2444 {
2445 #ifdef _WIN64
2446 // If it's a legal stack address map the entire region in
2447 //
2448 PEXCEPTION_RECORD exceptionRecord = exceptionInfo->ExceptionRecord;
2449 address addr = (address) exceptionRecord->ExceptionInformation[1];
2450 if (addr > thread->stack_reserved_zone_base() && addr < thread->stack_base()) {
2451 addr = (address)((uintptr_t)addr &
2452 (~((uintptr_t)os::vm_page_size() - (uintptr_t)1)));
2453 os::commit_memory((char *)addr, thread->stack_base() - addr,
2454 !ExecMem);
2455 return EXCEPTION_CONTINUE_EXECUTION;
2456 } else
2457 #endif
2458 {
2459 // Null pointer exception.
2460 if (!MacroAssembler::needs_explicit_null_check((intptr_t)addr)) {
2461 address stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
2462 if (stub != NULL) return Handle_Exception(exceptionInfo, stub);
2463 }
2464 report_error(t, exception_code, pc, exceptionInfo->ExceptionRecord,
2465 exceptionInfo->ContextRecord);
2466 return EXCEPTION_CONTINUE_SEARCH;
2467 }
2468 }
2469 }
2470
2471 #ifdef _WIN64
2472 // Special care for fast JNI field accessors.
2473 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks
2474 // in and the heap gets shrunk before the field access.
2475 if (exception_code == EXCEPTION_ACCESS_VIOLATION) {
2476 address addr = JNI_FastGetField::find_slowcase_pc(pc);
2477 if (addr != (address)-1) {
2478 return Handle_Exception(exceptionInfo, addr);
2479 }
2480 }
2481 #endif
2482
2483 // Stack overflow or null pointer exception in native code.
2484 report_error(t, exception_code, pc, exceptionInfo->ExceptionRecord,
2485 exceptionInfo->ContextRecord);
2486 return EXCEPTION_CONTINUE_SEARCH;
2487 } // /EXCEPTION_ACCESS_VIOLATION
2488 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
2489
2490 if (in_java) {
2491 switch (exception_code) {
2492 case EXCEPTION_INT_DIVIDE_BY_ZERO:
2493 return Handle_Exception(exceptionInfo, SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO));
2494
2495 case EXCEPTION_INT_OVERFLOW:
2496 return Handle_IDiv_Exception(exceptionInfo);
2497
2498 } // switch
2499 }
2500 if (((thread->thread_state() == _thread_in_Java) ||
2501 (thread->thread_state() == _thread_in_native)) &&
2502 exception_code != EXCEPTION_UNCAUGHT_CXX_EXCEPTION) {
2503 LONG result=Handle_FLT_Exception(exceptionInfo);
2504 if (result==EXCEPTION_CONTINUE_EXECUTION) return result;
2505 }
2506 }
2507
2508 if (exception_code != EXCEPTION_BREAKPOINT) {
2509 report_error(t, exception_code, pc, exceptionInfo->ExceptionRecord,
2510 exceptionInfo->ContextRecord);
2511 }
2512 return EXCEPTION_CONTINUE_SEARCH;
2513 }
2514
2515 #ifndef _WIN64
2516 // Special care for fast JNI accessors.
2517 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in and
2518 // the heap gets shrunk before the field access.
2519 // Need to install our own structured exception handler since native code may
2520 // install its own.
2521 LONG WINAPI fastJNIAccessorExceptionFilter(struct _EXCEPTION_POINTERS* exceptionInfo) {
2522 DWORD exception_code = exceptionInfo->ExceptionRecord->ExceptionCode;
2523 if (exception_code == EXCEPTION_ACCESS_VIOLATION) {
2524 address pc = (address) exceptionInfo->ContextRecord->Eip;
2525 address addr = JNI_FastGetField::find_slowcase_pc(pc);
2526 if (addr != (address)-1) {
2527 return Handle_Exception(exceptionInfo, addr);
2528 }
2529 }
2530 return EXCEPTION_CONTINUE_SEARCH;
2531 }
2532
2533 #define DEFINE_FAST_GETFIELD(Return, Fieldname, Result) \
2534 Return JNICALL jni_fast_Get##Result##Field_wrapper(JNIEnv *env, \
2535 jobject obj, \
2536 jfieldID fieldID) { \
2537 __try { \
2538 return (*JNI_FastGetField::jni_fast_Get##Result##Field_fp)(env, \
2539 obj, \
2540 fieldID); \
2541 } __except(fastJNIAccessorExceptionFilter((_EXCEPTION_POINTERS*) \
2542 _exception_info())) { \
2543 } \
2544 return 0; \
2545 }
2546
2547 DEFINE_FAST_GETFIELD(jboolean, bool, Boolean)
2548 DEFINE_FAST_GETFIELD(jbyte, byte, Byte)
2549 DEFINE_FAST_GETFIELD(jchar, char, Char)
2550 DEFINE_FAST_GETFIELD(jshort, short, Short)
2551 DEFINE_FAST_GETFIELD(jint, int, Int)
2552 DEFINE_FAST_GETFIELD(jlong, long, Long)
2553 DEFINE_FAST_GETFIELD(jfloat, float, Float)
2554 DEFINE_FAST_GETFIELD(jdouble, double, Double)
2555
2556 address os::win32::fast_jni_accessor_wrapper(BasicType type) {
2557 switch (type) {
2558 case T_BOOLEAN: return (address)jni_fast_GetBooleanField_wrapper;
2559 case T_BYTE: return (address)jni_fast_GetByteField_wrapper;
2560 case T_CHAR: return (address)jni_fast_GetCharField_wrapper;
2561 case T_SHORT: return (address)jni_fast_GetShortField_wrapper;
2562 case T_INT: return (address)jni_fast_GetIntField_wrapper;
2563 case T_LONG: return (address)jni_fast_GetLongField_wrapper;
2564 case T_FLOAT: return (address)jni_fast_GetFloatField_wrapper;
2565 case T_DOUBLE: return (address)jni_fast_GetDoubleField_wrapper;
2566 default: ShouldNotReachHere();
2567 }
2568 return (address)-1;
2569 }
2570 #endif
2571
2572 // Virtual Memory
2573
2574 int os::vm_page_size() { return os::win32::vm_page_size(); }
2575 int os::vm_allocation_granularity() {
2576 return os::win32::vm_allocation_granularity();
2577 }
2578
2579 // Windows large page support is available on Windows 2003. In order to use
2580 // large page memory, the administrator must first assign additional privilege
2581 // to the user:
2582 // + select Control Panel -> Administrative Tools -> Local Security Policy
2583 // + select Local Policies -> User Rights Assignment
2584 // + double click "Lock pages in memory", add users and/or groups
2585 // + reboot
2586 // Note the above steps are needed for administrator as well, as administrators
2587 // by default do not have the privilege to lock pages in memory.
2588 //
2589 // Note about Windows 2003: although the API supports committing large page
2590 // memory on a page-by-page basis and VirtualAlloc() returns success under this
2591 // scenario, I found through experiment it only uses large page if the entire
2592 // memory region is reserved and committed in a single VirtualAlloc() call.
2593 // This makes Windows large page support more or less like Solaris ISM, in
2594 // that the entire heap must be committed upfront. This probably will change
2595 // in the future, if so the code below needs to be revisited.
2596
2597 #ifndef MEM_LARGE_PAGES
2598 #define MEM_LARGE_PAGES 0x20000000
2599 #endif
2600
2601 static HANDLE _hProcess;
2602 static HANDLE _hToken;
2603
2604 // Container for NUMA node list info
2605 class NUMANodeListHolder {
2606 private:
2607 int *_numa_used_node_list; // allocated below
2608 int _numa_used_node_count;
2609
2610 void free_node_list() {
2611 if (_numa_used_node_list != NULL) {
2612 FREE_C_HEAP_ARRAY(int, _numa_used_node_list);
2613 }
2614 }
2615
2616 public:
2617 NUMANodeListHolder() {
2618 _numa_used_node_count = 0;
2619 _numa_used_node_list = NULL;
2620 // do rest of initialization in build routine (after function pointers are set up)
2621 }
2622
2623 ~NUMANodeListHolder() {
2624 free_node_list();
2625 }
2626
2627 bool build() {
2628 DWORD_PTR proc_aff_mask;
2629 DWORD_PTR sys_aff_mask;
2630 if (!GetProcessAffinityMask(GetCurrentProcess(), &proc_aff_mask, &sys_aff_mask)) return false;
2631 ULONG highest_node_number;
2632 if (!GetNumaHighestNodeNumber(&highest_node_number)) return false;
2633 free_node_list();
2634 _numa_used_node_list = NEW_C_HEAP_ARRAY(int, highest_node_number + 1, mtInternal);
2635 for (unsigned int i = 0; i <= highest_node_number; i++) {
2636 ULONGLONG proc_mask_numa_node;
2637 if (!GetNumaNodeProcessorMask(i, &proc_mask_numa_node)) return false;
2638 if ((proc_aff_mask & proc_mask_numa_node)!=0) {
2639 _numa_used_node_list[_numa_used_node_count++] = i;
2640 }
2641 }
2642 return (_numa_used_node_count > 1);
2643 }
2644
2645 int get_count() { return _numa_used_node_count; }
2646 int get_node_list_entry(int n) {
2647 // for indexes out of range, returns -1
2648 return (n < _numa_used_node_count ? _numa_used_node_list[n] : -1);
2649 }
2650
2651 } numa_node_list_holder;
2652
2653
2654
2655 static size_t _large_page_size = 0;
2656
2657 static bool request_lock_memory_privilege() {
2658 _hProcess = OpenProcess(PROCESS_QUERY_INFORMATION, FALSE,
2659 os::current_process_id());
2660
2661 LUID luid;
2662 if (_hProcess != NULL &&
2663 OpenProcessToken(_hProcess, TOKEN_ADJUST_PRIVILEGES, &_hToken) &&
2664 LookupPrivilegeValue(NULL, "SeLockMemoryPrivilege", &luid)) {
2665
2666 TOKEN_PRIVILEGES tp;
2667 tp.PrivilegeCount = 1;
2668 tp.Privileges[0].Luid = luid;
2669 tp.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED;
2670
2671 // AdjustTokenPrivileges() may return TRUE even when it couldn't change the
2672 // privilege. Check GetLastError() too. See MSDN document.
2673 if (AdjustTokenPrivileges(_hToken, false, &tp, sizeof(tp), NULL, NULL) &&
2674 (GetLastError() == ERROR_SUCCESS)) {
2675 return true;
2676 }
2677 }
2678
2679 return false;
2680 }
2681
2682 static void cleanup_after_large_page_init() {
2683 if (_hProcess) CloseHandle(_hProcess);
2684 _hProcess = NULL;
2685 if (_hToken) CloseHandle(_hToken);
2686 _hToken = NULL;
2687 }
2688
2689 static bool numa_interleaving_init() {
2690 bool success = false;
2691 bool use_numa_interleaving_specified = !FLAG_IS_DEFAULT(UseNUMAInterleaving);
2692
2693 // print a warning if UseNUMAInterleaving flag is specified on command line
2694 bool warn_on_failure = use_numa_interleaving_specified;
2695 #define WARN(msg) if (warn_on_failure) { warning(msg); }
2696
2697 // NUMAInterleaveGranularity cannot be less than vm_allocation_granularity (or _large_page_size if using large pages)
2698 size_t min_interleave_granularity = UseLargePages ? _large_page_size : os::vm_allocation_granularity();
2699 NUMAInterleaveGranularity = align_up(NUMAInterleaveGranularity, min_interleave_granularity);
2700
2701 if (numa_node_list_holder.build()) {
2702 if (log_is_enabled(Debug, os, cpu)) {
2703 Log(os, cpu) log;
2704 log.debug("NUMA UsedNodeCount=%d, namely ", numa_node_list_holder.get_count());
2705 for (int i = 0; i < numa_node_list_holder.get_count(); i++) {
2706 log.debug(" %d ", numa_node_list_holder.get_node_list_entry(i));
2707 }
2708 }
2709 success = true;
2710 } else {
2711 WARN("Process does not cover multiple NUMA nodes.");
2712 }
2713 if (!success) {
2714 if (use_numa_interleaving_specified) WARN("...Ignoring UseNUMAInterleaving flag.");
2715 }
2716 return success;
2717 #undef WARN
2718 }
2719
2720 // this routine is used whenever we need to reserve a contiguous VA range
2721 // but we need to make separate VirtualAlloc calls for each piece of the range
2722 // Reasons for doing this:
2723 // * UseLargePagesIndividualAllocation was set (normally only needed on WS2003 but possible to be set otherwise)
2724 // * UseNUMAInterleaving requires a separate node for each piece
2725 static char* allocate_pages_individually(size_t bytes, char* addr, DWORD flags,
2726 DWORD prot,
2727 bool should_inject_error = false) {
2728 char * p_buf;
2729 // note: at setup time we guaranteed that NUMAInterleaveGranularity was aligned up to a page size
2730 size_t page_size = UseLargePages ? _large_page_size : os::vm_allocation_granularity();
2731 size_t chunk_size = UseNUMAInterleaving ? NUMAInterleaveGranularity : page_size;
2732
2733 // first reserve enough address space in advance since we want to be
2734 // able to break a single contiguous virtual address range into multiple
2735 // large page commits but WS2003 does not allow reserving large page space
2736 // so we just use 4K pages for reserve, this gives us a legal contiguous
2737 // address space. then we will deallocate that reservation, and re alloc
2738 // using large pages
2739 const size_t size_of_reserve = bytes + chunk_size;
2740 if (bytes > size_of_reserve) {
2741 // Overflowed.
2742 return NULL;
2743 }
2744 p_buf = (char *) VirtualAlloc(addr,
2745 size_of_reserve, // size of Reserve
2746 MEM_RESERVE,
2747 PAGE_READWRITE);
2748 // If reservation failed, return NULL
2749 if (p_buf == NULL) return NULL;
2750 MemTracker::record_virtual_memory_reserve((address)p_buf, size_of_reserve, CALLER_PC);
2751 os::release_memory(p_buf, bytes + chunk_size);
2752
2753 // we still need to round up to a page boundary (in case we are using large pages)
2754 // but not to a chunk boundary (in case InterleavingGranularity doesn't align with page size)
2755 // instead we handle this in the bytes_to_rq computation below
2756 p_buf = align_up(p_buf, page_size);
2757
2758 // now go through and allocate one chunk at a time until all bytes are
2759 // allocated
2760 size_t bytes_remaining = bytes;
2761 // An overflow of align_up() would have been caught above
2762 // in the calculation of size_of_reserve.
2763 char * next_alloc_addr = p_buf;
2764 HANDLE hProc = GetCurrentProcess();
2765
2766 #ifdef ASSERT
2767 // Variable for the failure injection
2768 int ran_num = os::random();
2769 size_t fail_after = ran_num % bytes;
2770 #endif
2771
2772 int count=0;
2773 while (bytes_remaining) {
2774 // select bytes_to_rq to get to the next chunk_size boundary
2775
2776 size_t bytes_to_rq = MIN2(bytes_remaining, chunk_size - ((size_t)next_alloc_addr % chunk_size));
2777 // Note allocate and commit
2778 char * p_new;
2779
2780 #ifdef ASSERT
2781 bool inject_error_now = should_inject_error && (bytes_remaining <= fail_after);
2782 #else
2783 const bool inject_error_now = false;
2784 #endif
2785
2786 if (inject_error_now) {
2787 p_new = NULL;
2788 } else {
2789 if (!UseNUMAInterleaving) {
2790 p_new = (char *) VirtualAlloc(next_alloc_addr,
2791 bytes_to_rq,
2792 flags,
2793 prot);
2794 } else {
2795 // get the next node to use from the used_node_list
2796 assert(numa_node_list_holder.get_count() > 0, "Multiple NUMA nodes expected");
2797 DWORD node = numa_node_list_holder.get_node_list_entry(count % numa_node_list_holder.get_count());
2798 p_new = (char *)VirtualAllocExNuma(hProc, next_alloc_addr, bytes_to_rq, flags, prot, node);
2799 }
2800 }
2801
2802 if (p_new == NULL) {
2803 // Free any allocated pages
2804 if (next_alloc_addr > p_buf) {
2805 // Some memory was committed so release it.
2806 size_t bytes_to_release = bytes - bytes_remaining;
2807 // NMT has yet to record any individual blocks, so it
2808 // need to create a dummy 'reserve' record to match
2809 // the release.
2810 MemTracker::record_virtual_memory_reserve((address)p_buf,
2811 bytes_to_release, CALLER_PC);
2812 os::release_memory(p_buf, bytes_to_release);
2813 }
2814 #ifdef ASSERT
2815 if (should_inject_error) {
2816 log_develop_debug(pagesize)("Reserving pages individually failed.");
2817 }
2818 #endif
2819 return NULL;
2820 }
2821
2822 bytes_remaining -= bytes_to_rq;
2823 next_alloc_addr += bytes_to_rq;
2824 count++;
2825 }
2826 // Although the memory is allocated individually, it is returned as one.
2827 // NMT records it as one block.
2828 if ((flags & MEM_COMMIT) != 0) {
2829 MemTracker::record_virtual_memory_reserve_and_commit((address)p_buf, bytes, CALLER_PC);
2830 } else {
2831 MemTracker::record_virtual_memory_reserve((address)p_buf, bytes, CALLER_PC);
2832 }
2833
2834 // made it this far, success
2835 return p_buf;
2836 }
2837
2838
2839
2840 void os::large_page_init() {
2841 if (!UseLargePages) return;
2842
2843 // print a warning if any large page related flag is specified on command line
2844 bool warn_on_failure = !FLAG_IS_DEFAULT(UseLargePages) ||
2845 !FLAG_IS_DEFAULT(LargePageSizeInBytes);
2846 bool success = false;
2847
2848 #define WARN(msg) if (warn_on_failure) { warning(msg); }
2849 if (request_lock_memory_privilege()) {
2850 size_t s = GetLargePageMinimum();
2851 if (s) {
2852 #if defined(IA32) || defined(AMD64)
2853 if (s > 4*M || LargePageSizeInBytes > 4*M) {
2854 WARN("JVM cannot use large pages bigger than 4mb.");
2855 } else {
2856 #endif
2857 if (LargePageSizeInBytes && LargePageSizeInBytes % s == 0) {
2858 _large_page_size = LargePageSizeInBytes;
2859 } else {
2860 _large_page_size = s;
2861 }
2862 success = true;
2863 #if defined(IA32) || defined(AMD64)
2864 }
2865 #endif
2866 } else {
2867 WARN("Large page is not supported by the processor.");
2868 }
2869 } else {
2870 WARN("JVM cannot use large page memory because it does not have enough privilege to lock pages in memory.");
2871 }
2872 #undef WARN
2873
2874 const size_t default_page_size = (size_t) vm_page_size();
2875 if (success && _large_page_size > default_page_size) {
2876 _page_sizes[0] = _large_page_size;
2877 _page_sizes[1] = default_page_size;
2878 _page_sizes[2] = 0;
2879 }
2880
2881 cleanup_after_large_page_init();
2882 UseLargePages = success;
2883 }
2884
2885 // On win32, one cannot release just a part of reserved memory, it's an
2886 // all or nothing deal. When we split a reservation, we must break the
2887 // reservation into two reservations.
2888 void os::pd_split_reserved_memory(char *base, size_t size, size_t split,
2889 bool realloc) {
2890 if (size > 0) {
2891 release_memory(base, size);
2892 if (realloc) {
2893 reserve_memory(split, base);
2894 }
2895 if (size != split) {
2896 reserve_memory(size - split, base + split);
2897 }
2898 }
2899 }
2900
2901 // Multiple threads can race in this code but it's not possible to unmap small sections of
2902 // virtual space to get requested alignment, like posix-like os's.
2903 // Windows prevents multiple thread from remapping over each other so this loop is thread-safe.
2904 char* os::reserve_memory_aligned(size_t size, size_t alignment) {
2905 assert((alignment & (os::vm_allocation_granularity() - 1)) == 0,
2906 "Alignment must be a multiple of allocation granularity (page size)");
2907 assert((size & (alignment -1)) == 0, "size must be 'alignment' aligned");
2908
2909 size_t extra_size = size + alignment;
2910 assert(extra_size >= size, "overflow, size is too large to allow alignment");
2911
2912 char* aligned_base = NULL;
2913
2914 do {
2915 char* extra_base = os::reserve_memory(extra_size, NULL, alignment);
2916 if (extra_base == NULL) {
2917 return NULL;
2918 }
2919 // Do manual alignment
2920 aligned_base = align_up(extra_base, alignment);
2921
2922 os::release_memory(extra_base, extra_size);
2923
2924 aligned_base = os::reserve_memory(size, aligned_base);
2925
2926 } while (aligned_base == NULL);
2927
2928 return aligned_base;
2929 }
2930
2931 char* os::pd_reserve_memory(size_t bytes, char* addr, size_t alignment_hint) {
2932 assert((size_t)addr % os::vm_allocation_granularity() == 0,
2933 "reserve alignment");
2934 assert(bytes % os::vm_page_size() == 0, "reserve page size");
2935 char* res;
2936 // note that if UseLargePages is on, all the areas that require interleaving
2937 // will go thru reserve_memory_special rather than thru here.
2938 bool use_individual = (UseNUMAInterleaving && !UseLargePages);
2939 if (!use_individual) {
2940 res = (char*)VirtualAlloc(addr, bytes, MEM_RESERVE, PAGE_READWRITE);
2941 } else {
2942 elapsedTimer reserveTimer;
2943 if (Verbose && PrintMiscellaneous) reserveTimer.start();
2944 // in numa interleaving, we have to allocate pages individually
2945 // (well really chunks of NUMAInterleaveGranularity size)
2946 res = allocate_pages_individually(bytes, addr, MEM_RESERVE, PAGE_READWRITE);
2947 if (res == NULL) {
2948 warning("NUMA page allocation failed");
2949 }
2950 if (Verbose && PrintMiscellaneous) {
2951 reserveTimer.stop();
2952 tty->print_cr("reserve_memory of %Ix bytes took " JLONG_FORMAT " ms (" JLONG_FORMAT " ticks)", bytes,
2953 reserveTimer.milliseconds(), reserveTimer.ticks());
2954 }
2955 }
2956 assert(res == NULL || addr == NULL || addr == res,
2957 "Unexpected address from reserve.");
2958
2959 return res;
2960 }
2961
2962 // Reserve memory at an arbitrary address, only if that area is
2963 // available (and not reserved for something else).
2964 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2965 // Windows os::reserve_memory() fails of the requested address range is
2966 // not avilable.
2967 return reserve_memory(bytes, requested_addr);
2968 }
2969
2970 size_t os::large_page_size() {
2971 return _large_page_size;
2972 }
2973
2974 bool os::can_commit_large_page_memory() {
2975 // Windows only uses large page memory when the entire region is reserved
2976 // and committed in a single VirtualAlloc() call. This may change in the
2977 // future, but with Windows 2003 it's not possible to commit on demand.
2978 return false;
2979 }
2980
2981 bool os::can_execute_large_page_memory() {
2982 return true;
2983 }
2984
2985 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* addr,
2986 bool exec) {
2987 assert(UseLargePages, "only for large pages");
2988
2989 if (!is_aligned(bytes, os::large_page_size()) || alignment > os::large_page_size()) {
2990 return NULL; // Fallback to small pages.
2991 }
2992
2993 const DWORD prot = exec ? PAGE_EXECUTE_READWRITE : PAGE_READWRITE;
2994 const DWORD flags = MEM_RESERVE | MEM_COMMIT | MEM_LARGE_PAGES;
2995
2996 // with large pages, there are two cases where we need to use Individual Allocation
2997 // 1) the UseLargePagesIndividualAllocation flag is set (set by default on WS2003)
2998 // 2) NUMA Interleaving is enabled, in which case we use a different node for each page
2999 if (UseLargePagesIndividualAllocation || UseNUMAInterleaving) {
3000 log_debug(pagesize)("Reserving large pages individually.");
3001
3002 char * p_buf = allocate_pages_individually(bytes, addr, flags, prot, LargePagesIndividualAllocationInjectError);
3003 if (p_buf == NULL) {
3004 // give an appropriate warning message
3005 if (UseNUMAInterleaving) {
3006 warning("NUMA large page allocation failed, UseLargePages flag ignored");
3007 }
3008 if (UseLargePagesIndividualAllocation) {
3009 warning("Individually allocated large pages failed, "
3010 "use -XX:-UseLargePagesIndividualAllocation to turn off");
3011 }
3012 return NULL;
3013 }
3014
3015 return p_buf;
3016
3017 } else {
3018 log_debug(pagesize)("Reserving large pages in a single large chunk.");
3019
3020 // normal policy just allocate it all at once
3021 DWORD flag = MEM_RESERVE | MEM_COMMIT | MEM_LARGE_PAGES;
3022 char * res = (char *)VirtualAlloc(addr, bytes, flag, prot);
3023 if (res != NULL) {
3024 MemTracker::record_virtual_memory_reserve_and_commit((address)res, bytes, CALLER_PC);
3025 }
3026
3027 return res;
3028 }
3029 }
3030
3031 bool os::release_memory_special(char* base, size_t bytes) {
3032 assert(base != NULL, "Sanity check");
3033 return release_memory(base, bytes);
3034 }
3035
3036 void os::print_statistics() {
3037 }
3038
3039 static void warn_fail_commit_memory(char* addr, size_t bytes, bool exec) {
3040 int err = os::get_last_error();
3041 char buf[256];
3042 size_t buf_len = os::lasterror(buf, sizeof(buf));
3043 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT
3044 ", %d) failed; error='%s' (DOS error/errno=%d)", addr, bytes,
3045 exec, buf_len != 0 ? buf : "<no_error_string>", err);
3046 }
3047
3048 bool os::pd_commit_memory(char* addr, size_t bytes, bool exec) {
3049 if (bytes == 0) {
3050 // Don't bother the OS with noops.
3051 return true;
3052 }
3053 assert((size_t) addr % os::vm_page_size() == 0, "commit on page boundaries");
3054 assert(bytes % os::vm_page_size() == 0, "commit in page-sized chunks");
3055 // Don't attempt to print anything if the OS call fails. We're
3056 // probably low on resources, so the print itself may cause crashes.
3057
3058 // unless we have NUMAInterleaving enabled, the range of a commit
3059 // is always within a reserve covered by a single VirtualAlloc
3060 // in that case we can just do a single commit for the requested size
3061 if (!UseNUMAInterleaving) {
3062 if (VirtualAlloc(addr, bytes, MEM_COMMIT, PAGE_READWRITE) == NULL) {
3063 NOT_PRODUCT(warn_fail_commit_memory(addr, bytes, exec);)
3064 return false;
3065 }
3066 if (exec) {
3067 DWORD oldprot;
3068 // Windows doc says to use VirtualProtect to get execute permissions
3069 if (!VirtualProtect(addr, bytes, PAGE_EXECUTE_READWRITE, &oldprot)) {
3070 NOT_PRODUCT(warn_fail_commit_memory(addr, bytes, exec);)
3071 return false;
3072 }
3073 }
3074 return true;
3075 } else {
3076
3077 // when NUMAInterleaving is enabled, the commit might cover a range that
3078 // came from multiple VirtualAlloc reserves (using allocate_pages_individually).
3079 // VirtualQuery can help us determine that. The RegionSize that VirtualQuery
3080 // returns represents the number of bytes that can be committed in one step.
3081 size_t bytes_remaining = bytes;
3082 char * next_alloc_addr = addr;
3083 while (bytes_remaining > 0) {
3084 MEMORY_BASIC_INFORMATION alloc_info;
3085 VirtualQuery(next_alloc_addr, &alloc_info, sizeof(alloc_info));
3086 size_t bytes_to_rq = MIN2(bytes_remaining, (size_t)alloc_info.RegionSize);
3087 if (VirtualAlloc(next_alloc_addr, bytes_to_rq, MEM_COMMIT,
3088 PAGE_READWRITE) == NULL) {
3089 NOT_PRODUCT(warn_fail_commit_memory(next_alloc_addr, bytes_to_rq,
3090 exec);)
3091 return false;
3092 }
3093 if (exec) {
3094 DWORD oldprot;
3095 if (!VirtualProtect(next_alloc_addr, bytes_to_rq,
3096 PAGE_EXECUTE_READWRITE, &oldprot)) {
3097 NOT_PRODUCT(warn_fail_commit_memory(next_alloc_addr, bytes_to_rq,
3098 exec);)
3099 return false;
3100 }
3101 }
3102 bytes_remaining -= bytes_to_rq;
3103 next_alloc_addr += bytes_to_rq;
3104 }
3105 }
3106 // if we made it this far, return true
3107 return true;
3108 }
3109
3110 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
3111 bool exec) {
3112 // alignment_hint is ignored on this OS
3113 return pd_commit_memory(addr, size, exec);
3114 }
3115
3116 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
3117 const char* mesg) {
3118 assert(mesg != NULL, "mesg must be specified");
3119 if (!pd_commit_memory(addr, size, exec)) {
3120 warn_fail_commit_memory(addr, size, exec);
3121 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, "%s", mesg);
3122 }
3123 }
3124
3125 void os::pd_commit_memory_or_exit(char* addr, size_t size,
3126 size_t alignment_hint, bool exec,
3127 const char* mesg) {
3128 // alignment_hint is ignored on this OS
3129 pd_commit_memory_or_exit(addr, size, exec, mesg);
3130 }
3131
3132 bool os::pd_uncommit_memory(char* addr, size_t bytes) {
3133 if (bytes == 0) {
3134 // Don't bother the OS with noops.
3135 return true;
3136 }
3137 assert((size_t) addr % os::vm_page_size() == 0, "uncommit on page boundaries");
3138 assert(bytes % os::vm_page_size() == 0, "uncommit in page-sized chunks");
3139 return (VirtualFree(addr, bytes, MEM_DECOMMIT) != 0);
3140 }
3141
3142 bool os::pd_release_memory(char* addr, size_t bytes) {
3143 return VirtualFree(addr, 0, MEM_RELEASE) != 0;
3144 }
3145
3146 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
3147 return os::commit_memory(addr, size, !ExecMem);
3148 }
3149
3150 bool os::remove_stack_guard_pages(char* addr, size_t size) {
3151 return os::uncommit_memory(addr, size);
3152 }
3153
3154 static bool protect_pages_individually(char* addr, size_t bytes, unsigned int p, DWORD *old_status) {
3155 uint count = 0;
3156 bool ret = false;
3157 size_t bytes_remaining = bytes;
3158 char * next_protect_addr = addr;
3159
3160 // Use VirtualQuery() to get the chunk size.
3161 while (bytes_remaining) {
3162 MEMORY_BASIC_INFORMATION alloc_info;
3163 if (VirtualQuery(next_protect_addr, &alloc_info, sizeof(alloc_info)) == 0) {
3164 return false;
3165 }
3166
3167 size_t bytes_to_protect = MIN2(bytes_remaining, (size_t)alloc_info.RegionSize);
3168 // We used different API at allocate_pages_individually() based on UseNUMAInterleaving,
3169 // but we don't distinguish here as both cases are protected by same API.
3170 ret = VirtualProtect(next_protect_addr, bytes_to_protect, p, old_status) != 0;
3171 warning("Failed protecting pages individually for chunk #%u", count);
3172 if (!ret) {
3173 return false;
3174 }
3175
3176 bytes_remaining -= bytes_to_protect;
3177 next_protect_addr += bytes_to_protect;
3178 count++;
3179 }
3180 return ret;
3181 }
3182
3183 // Set protections specified
3184 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
3185 bool is_committed) {
3186 unsigned int p = 0;
3187 switch (prot) {
3188 case MEM_PROT_NONE: p = PAGE_NOACCESS; break;
3189 case MEM_PROT_READ: p = PAGE_READONLY; break;
3190 case MEM_PROT_RW: p = PAGE_READWRITE; break;
3191 case MEM_PROT_RWX: p = PAGE_EXECUTE_READWRITE; break;
3192 default:
3193 ShouldNotReachHere();
3194 }
3195
3196 DWORD old_status;
3197
3198 // Strange enough, but on Win32 one can change protection only for committed
3199 // memory, not a big deal anyway, as bytes less or equal than 64K
3200 if (!is_committed) {
3201 commit_memory_or_exit(addr, bytes, prot == MEM_PROT_RWX,
3202 "cannot commit protection page");
3203 }
3204 // One cannot use os::guard_memory() here, as on Win32 guard page
3205 // have different (one-shot) semantics, from MSDN on PAGE_GUARD:
3206 //
3207 // Pages in the region become guard pages. Any attempt to access a guard page
3208 // causes the system to raise a STATUS_GUARD_PAGE exception and turn off
3209 // the guard page status. Guard pages thus act as a one-time access alarm.
3210 bool ret;
3211 if (UseNUMAInterleaving) {
3212 // If UseNUMAInterleaving is enabled, the pages may have been allocated a chunk at a time,
3213 // so we must protect the chunks individually.
3214 ret = protect_pages_individually(addr, bytes, p, &old_status);
3215 } else {
3216 ret = VirtualProtect(addr, bytes, p, &old_status) != 0;
3217 }
3218 #ifdef ASSERT
3219 if (!ret) {
3220 int err = os::get_last_error();
3221 char buf[256];
3222 size_t buf_len = os::lasterror(buf, sizeof(buf));
3223 warning("INFO: os::protect_memory(" PTR_FORMAT ", " SIZE_FORMAT
3224 ") failed; error='%s' (DOS error/errno=%d)", addr, bytes,
3225 buf_len != 0 ? buf : "<no_error_string>", err);
3226 }
3227 #endif
3228 return ret;
3229 }
3230
3231 bool os::guard_memory(char* addr, size_t bytes) {
3232 DWORD old_status;
3233 return VirtualProtect(addr, bytes, PAGE_READWRITE | PAGE_GUARD, &old_status) != 0;
3234 }
3235
3236 bool os::unguard_memory(char* addr, size_t bytes) {
3237 DWORD old_status;
3238 return VirtualProtect(addr, bytes, PAGE_READWRITE, &old_status) != 0;
3239 }
3240
3241 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) { }
3242 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) { }
3243 void os::numa_make_global(char *addr, size_t bytes) { }
3244 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) { }
3245 bool os::numa_topology_changed() { return false; }
3246 size_t os::numa_get_groups_num() { return MAX2(numa_node_list_holder.get_count(), 1); }
3247 int os::numa_get_group_id() { return 0; }
3248 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
3249 if (numa_node_list_holder.get_count() == 0 && size > 0) {
3250 // Provide an answer for UMA systems
3251 ids[0] = 0;
3252 return 1;
3253 } else {
3254 // check for size bigger than actual groups_num
3255 size = MIN2(size, numa_get_groups_num());
3256 for (int i = 0; i < (int)size; i++) {
3257 ids[i] = numa_node_list_holder.get_node_list_entry(i);
3258 }
3259 return size;
3260 }
3261 }
3262
3263 bool os::get_page_info(char *start, page_info* info) {
3264 return false;
3265 }
3266
3267 char *os::scan_pages(char *start, char* end, page_info* page_expected,
3268 page_info* page_found) {
3269 return end;
3270 }
3271
3272 char* os::non_memory_address_word() {
3273 // Must never look like an address returned by reserve_memory,
3274 // even in its subfields (as defined by the CPU immediate fields,
3275 // if the CPU splits constants across multiple instructions).
3276 return (char*)-1;
3277 }
3278
3279 #define MAX_ERROR_COUNT 100
3280 #define SYS_THREAD_ERROR 0xffffffffUL
3281
3282 void os::pd_start_thread(Thread* thread) {
3283 DWORD ret = ResumeThread(thread->osthread()->thread_handle());
3284 // Returns previous suspend state:
3285 // 0: Thread was not suspended
3286 // 1: Thread is running now
3287 // >1: Thread is still suspended.
3288 assert(ret != SYS_THREAD_ERROR, "StartThread failed"); // should propagate back
3289 }
3290
3291 class HighResolutionInterval : public CHeapObj<mtThread> {
3292 // The default timer resolution seems to be 10 milliseconds.
3293 // (Where is this written down?)
3294 // If someone wants to sleep for only a fraction of the default,
3295 // then we set the timer resolution down to 1 millisecond for
3296 // the duration of their interval.
3297 // We carefully set the resolution back, since otherwise we
3298 // seem to incur an overhead (3%?) that we don't need.
3299 // CONSIDER: if ms is small, say 3, then we should run with a high resolution time.
3300 // Buf if ms is large, say 500, or 503, we should avoid the call to timeBeginPeriod().
3301 // Alternatively, we could compute the relative error (503/500 = .6%) and only use
3302 // timeBeginPeriod() if the relative error exceeded some threshold.
3303 // timeBeginPeriod() has been linked to problems with clock drift on win32 systems and
3304 // to decreased efficiency related to increased timer "tick" rates. We want to minimize
3305 // (a) calls to timeBeginPeriod() and timeEndPeriod() and (b) time spent with high
3306 // resolution timers running.
3307 private:
3308 jlong resolution;
3309 public:
3310 HighResolutionInterval(jlong ms) {
3311 resolution = ms % 10L;
3312 if (resolution != 0) {
3313 MMRESULT result = timeBeginPeriod(1L);
3314 }
3315 }
3316 ~HighResolutionInterval() {
3317 if (resolution != 0) {
3318 MMRESULT result = timeEndPeriod(1L);
3319 }
3320 resolution = 0L;
3321 }
3322 };
3323
3324 int os::sleep(Thread* thread, jlong ms, bool interruptable) {
3325 jlong limit = (jlong) MAXDWORD;
3326
3327 while (ms > limit) {
3328 int res;
3329 if ((res = sleep(thread, limit, interruptable)) != OS_TIMEOUT) {
3330 return res;
3331 }
3332 ms -= limit;
3333 }
3334
3335 assert(thread == Thread::current(), "thread consistency check");
3336 OSThread* osthread = thread->osthread();
3337 OSThreadWaitState osts(osthread, false /* not Object.wait() */);
3338 int result;
3339 if (interruptable) {
3340 assert(thread->is_Java_thread(), "must be java thread");
3341 JavaThread *jt = (JavaThread *) thread;
3342 ThreadBlockInVM tbivm(jt);
3343
3344 jt->set_suspend_equivalent();
3345 // cleared by handle_special_suspend_equivalent_condition() or
3346 // java_suspend_self() via check_and_wait_while_suspended()
3347
3348 HANDLE events[1];
3349 events[0] = osthread->interrupt_event();
3350 HighResolutionInterval *phri=NULL;
3351 if (!ForceTimeHighResolution) {
3352 phri = new HighResolutionInterval(ms);
3353 }
3354 if (WaitForMultipleObjects(1, events, FALSE, (DWORD)ms) == WAIT_TIMEOUT) {
3355 result = OS_TIMEOUT;
3356 } else {
3357 ResetEvent(osthread->interrupt_event());
3358 osthread->set_interrupted(false);
3359 result = OS_INTRPT;
3360 }
3361 delete phri; //if it is NULL, harmless
3362
3363 // were we externally suspended while we were waiting?
3364 jt->check_and_wait_while_suspended();
3365 } else {
3366 assert(!thread->is_Java_thread(), "must not be java thread");
3367 Sleep((long) ms);
3368 result = OS_TIMEOUT;
3369 }
3370 return result;
3371 }
3372
3373 // Short sleep, direct OS call.
3374 //
3375 // ms = 0, means allow others (if any) to run.
3376 //
3377 void os::naked_short_sleep(jlong ms) {
3378 assert(ms < 1000, "Un-interruptable sleep, short time use only");
3379 Sleep(ms);
3380 }
3381
3382 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
3383 void os::infinite_sleep() {
3384 while (true) { // sleep forever ...
3385 Sleep(100000); // ... 100 seconds at a time
3386 }
3387 }
3388
3389 typedef BOOL (WINAPI * STTSignature)(void);
3390
3391 void os::naked_yield() {
3392 // Consider passing back the return value from SwitchToThread().
3393 SwitchToThread();
3394 }
3395
3396 // Win32 only gives you access to seven real priorities at a time,
3397 // so we compress Java's ten down to seven. It would be better
3398 // if we dynamically adjusted relative priorities.
3399
3400 int os::java_to_os_priority[CriticalPriority + 1] = {
3401 THREAD_PRIORITY_IDLE, // 0 Entry should never be used
3402 THREAD_PRIORITY_LOWEST, // 1 MinPriority
3403 THREAD_PRIORITY_LOWEST, // 2
3404 THREAD_PRIORITY_BELOW_NORMAL, // 3
3405 THREAD_PRIORITY_BELOW_NORMAL, // 4
3406 THREAD_PRIORITY_NORMAL, // 5 NormPriority
3407 THREAD_PRIORITY_NORMAL, // 6
3408 THREAD_PRIORITY_ABOVE_NORMAL, // 7
3409 THREAD_PRIORITY_ABOVE_NORMAL, // 8
3410 THREAD_PRIORITY_HIGHEST, // 9 NearMaxPriority
3411 THREAD_PRIORITY_HIGHEST, // 10 MaxPriority
3412 THREAD_PRIORITY_HIGHEST // 11 CriticalPriority
3413 };
3414
3415 int prio_policy1[CriticalPriority + 1] = {
3416 THREAD_PRIORITY_IDLE, // 0 Entry should never be used
3417 THREAD_PRIORITY_LOWEST, // 1 MinPriority
3418 THREAD_PRIORITY_LOWEST, // 2
3419 THREAD_PRIORITY_BELOW_NORMAL, // 3
3420 THREAD_PRIORITY_BELOW_NORMAL, // 4
3421 THREAD_PRIORITY_NORMAL, // 5 NormPriority
3422 THREAD_PRIORITY_ABOVE_NORMAL, // 6
3423 THREAD_PRIORITY_ABOVE_NORMAL, // 7
3424 THREAD_PRIORITY_HIGHEST, // 8
3425 THREAD_PRIORITY_HIGHEST, // 9 NearMaxPriority
3426 THREAD_PRIORITY_TIME_CRITICAL, // 10 MaxPriority
3427 THREAD_PRIORITY_TIME_CRITICAL // 11 CriticalPriority
3428 };
3429
3430 static int prio_init() {
3431 // If ThreadPriorityPolicy is 1, switch tables
3432 if (ThreadPriorityPolicy == 1) {
3433 int i;
3434 for (i = 0; i < CriticalPriority + 1; i++) {
3435 os::java_to_os_priority[i] = prio_policy1[i];
3436 }
3437 }
3438 if (UseCriticalJavaThreadPriority) {
3439 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
3440 }
3441 return 0;
3442 }
3443
3444 OSReturn os::set_native_priority(Thread* thread, int priority) {
3445 if (!UseThreadPriorities) return OS_OK;
3446 bool ret = SetThreadPriority(thread->osthread()->thread_handle(), priority) != 0;
3447 return ret ? OS_OK : OS_ERR;
3448 }
3449
3450 OSReturn os::get_native_priority(const Thread* const thread,
3451 int* priority_ptr) {
3452 if (!UseThreadPriorities) {
3453 *priority_ptr = java_to_os_priority[NormPriority];
3454 return OS_OK;
3455 }
3456 int os_prio = GetThreadPriority(thread->osthread()->thread_handle());
3457 if (os_prio == THREAD_PRIORITY_ERROR_RETURN) {
3458 assert(false, "GetThreadPriority failed");
3459 return OS_ERR;
3460 }
3461 *priority_ptr = os_prio;
3462 return OS_OK;
3463 }
3464
3465
3466 // Hint to the underlying OS that a task switch would not be good.
3467 // Void return because it's a hint and can fail.
3468 void os::hint_no_preempt() {}
3469
3470 void os::interrupt(Thread* thread) {
3471 debug_only(Thread::check_for_dangling_thread_pointer(thread);)
3472
3473 OSThread* osthread = thread->osthread();
3474 osthread->set_interrupted(true);
3475 // More than one thread can get here with the same value of osthread,
3476 // resulting in multiple notifications. We do, however, want the store
3477 // to interrupted() to be visible to other threads before we post
3478 // the interrupt event.
3479 OrderAccess::release();
3480 SetEvent(osthread->interrupt_event());
3481 // For JSR166: unpark after setting status
3482 if (thread->is_Java_thread()) {
3483 ((JavaThread*)thread)->parker()->unpark();
3484 }
3485
3486 ParkEvent * ev = thread->_ParkEvent;
3487 if (ev != NULL) ev->unpark();
3488 }
3489
3490
3491 bool os::is_interrupted(Thread* thread, bool clear_interrupted) {
3492 debug_only(Thread::check_for_dangling_thread_pointer(thread);)
3493
3494 OSThread* osthread = thread->osthread();
3495 // There is no synchronization between the setting of the interrupt
3496 // and it being cleared here. It is critical - see 6535709 - that
3497 // we only clear the interrupt state, and reset the interrupt event,
3498 // if we are going to report that we were indeed interrupted - else
3499 // an interrupt can be "lost", leading to spurious wakeups or lost wakeups
3500 // depending on the timing. By checking thread interrupt event to see
3501 // if the thread gets real interrupt thus prevent spurious wakeup.
3502 bool interrupted = osthread->interrupted() && (WaitForSingleObject(osthread->interrupt_event(), 0) == WAIT_OBJECT_0);
3503 if (interrupted && clear_interrupted) {
3504 osthread->set_interrupted(false);
3505 ResetEvent(osthread->interrupt_event());
3506 } // Otherwise leave the interrupted state alone
3507
3508 return interrupted;
3509 }
3510
3511 // GetCurrentThreadId() returns DWORD
3512 intx os::current_thread_id() { return GetCurrentThreadId(); }
3513
3514 static int _initial_pid = 0;
3515
3516 int os::current_process_id() {
3517 return (_initial_pid ? _initial_pid : _getpid());
3518 }
3519
3520 int os::win32::_vm_page_size = 0;
3521 int os::win32::_vm_allocation_granularity = 0;
3522 int os::win32::_processor_type = 0;
3523 // Processor level is not available on non-NT systems, use vm_version instead
3524 int os::win32::_processor_level = 0;
3525 julong os::win32::_physical_memory = 0;
3526 size_t os::win32::_default_stack_size = 0;
3527
3528 intx os::win32::_os_thread_limit = 0;
3529 volatile intx os::win32::_os_thread_count = 0;
3530
3531 bool os::win32::_is_windows_server = false;
3532
3533 // 6573254
3534 // Currently, the bug is observed across all the supported Windows releases,
3535 // including the latest one (as of this writing - Windows Server 2012 R2)
3536 bool os::win32::_has_exit_bug = true;
3537
3538 void os::win32::initialize_system_info() {
3539 SYSTEM_INFO si;
3540 GetSystemInfo(&si);
3541 _vm_page_size = si.dwPageSize;
3542 _vm_allocation_granularity = si.dwAllocationGranularity;
3543 _processor_type = si.dwProcessorType;
3544 _processor_level = si.wProcessorLevel;
3545 set_processor_count(si.dwNumberOfProcessors);
3546
3547 MEMORYSTATUSEX ms;
3548 ms.dwLength = sizeof(ms);
3549
3550 // also returns dwAvailPhys (free physical memory bytes), dwTotalVirtual, dwAvailVirtual,
3551 // dwMemoryLoad (% of memory in use)
3552 GlobalMemoryStatusEx(&ms);
3553 _physical_memory = ms.ullTotalPhys;
3554
3555 if (FLAG_IS_DEFAULT(MaxRAM)) {
3556 // Adjust MaxRAM according to the maximum virtual address space available.
3557 FLAG_SET_DEFAULT(MaxRAM, MIN2(MaxRAM, (uint64_t) ms.ullTotalVirtual));
3558 }
3559
3560 OSVERSIONINFOEX oi;
3561 oi.dwOSVersionInfoSize = sizeof(OSVERSIONINFOEX);
3562 GetVersionEx((OSVERSIONINFO*)&oi);
3563 switch (oi.dwPlatformId) {
3564 case VER_PLATFORM_WIN32_NT:
3565 {
3566 int os_vers = oi.dwMajorVersion * 1000 + oi.dwMinorVersion;
3567 if (oi.wProductType == VER_NT_DOMAIN_CONTROLLER ||
3568 oi.wProductType == VER_NT_SERVER) {
3569 _is_windows_server = true;
3570 }
3571 }
3572 break;
3573 default: fatal("Unknown platform");
3574 }
3575
3576 _default_stack_size = os::current_stack_size();
3577 assert(_default_stack_size > (size_t) _vm_page_size, "invalid stack size");
3578 assert((_default_stack_size & (_vm_page_size - 1)) == 0,
3579 "stack size not a multiple of page size");
3580
3581 initialize_performance_counter();
3582 }
3583
3584
3585 HINSTANCE os::win32::load_Windows_dll(const char* name, char *ebuf,
3586 int ebuflen) {
3587 char path[MAX_PATH];
3588 DWORD size;
3589 DWORD pathLen = (DWORD)sizeof(path);
3590 HINSTANCE result = NULL;
3591
3592 // only allow library name without path component
3593 assert(strchr(name, '\\') == NULL, "path not allowed");
3594 assert(strchr(name, ':') == NULL, "path not allowed");
3595 if (strchr(name, '\\') != NULL || strchr(name, ':') != NULL) {
3596 jio_snprintf(ebuf, ebuflen,
3597 "Invalid parameter while calling os::win32::load_windows_dll(): cannot take path: %s", name);
3598 return NULL;
3599 }
3600
3601 // search system directory
3602 if ((size = GetSystemDirectory(path, pathLen)) > 0) {
3603 if (size >= pathLen) {
3604 return NULL; // truncated
3605 }
3606 if (jio_snprintf(path + size, pathLen - size, "\\%s", name) == -1) {
3607 return NULL; // truncated
3608 }
3609 if ((result = (HINSTANCE)os::dll_load(path, ebuf, ebuflen)) != NULL) {
3610 return result;
3611 }
3612 }
3613
3614 // try Windows directory
3615 if ((size = GetWindowsDirectory(path, pathLen)) > 0) {
3616 if (size >= pathLen) {
3617 return NULL; // truncated
3618 }
3619 if (jio_snprintf(path + size, pathLen - size, "\\%s", name) == -1) {
3620 return NULL; // truncated
3621 }
3622 if ((result = (HINSTANCE)os::dll_load(path, ebuf, ebuflen)) != NULL) {
3623 return result;
3624 }
3625 }
3626
3627 jio_snprintf(ebuf, ebuflen,
3628 "os::win32::load_windows_dll() cannot load %s from system directories.", name);
3629 return NULL;
3630 }
3631
3632 #define MAXIMUM_THREADS_TO_KEEP (16 * MAXIMUM_WAIT_OBJECTS)
3633 #define EXIT_TIMEOUT 300000 /* 5 minutes */
3634
3635 static BOOL CALLBACK init_crit_sect_call(PINIT_ONCE, PVOID pcrit_sect, PVOID*) {
3636 InitializeCriticalSection((CRITICAL_SECTION*)pcrit_sect);
3637 return TRUE;
3638 }
3639
3640 int os::win32::exit_process_or_thread(Ept what, int exit_code) {
3641 // Basic approach:
3642 // - Each exiting thread registers its intent to exit and then does so.
3643 // - A thread trying to terminate the process must wait for all
3644 // threads currently exiting to complete their exit.
3645
3646 if (os::win32::has_exit_bug()) {
3647 // The array holds handles of the threads that have started exiting by calling
3648 // _endthreadex().
3649 // Should be large enough to avoid blocking the exiting thread due to lack of
3650 // a free slot.
3651 static HANDLE handles[MAXIMUM_THREADS_TO_KEEP];
3652 static int handle_count = 0;
3653
3654 static INIT_ONCE init_once_crit_sect = INIT_ONCE_STATIC_INIT;
3655 static CRITICAL_SECTION crit_sect;
3656 static volatile DWORD process_exiting = 0;
3657 int i, j;
3658 DWORD res;
3659 HANDLE hproc, hthr;
3660
3661 // We only attempt to register threads until a process exiting
3662 // thread manages to set the process_exiting flag. Any threads
3663 // that come through here after the process_exiting flag is set
3664 // are unregistered and will be caught in the SuspendThread()
3665 // infinite loop below.
3666 bool registered = false;
3667
3668 // The first thread that reached this point, initializes the critical section.
3669 if (!InitOnceExecuteOnce(&init_once_crit_sect, init_crit_sect_call, &crit_sect, NULL)) {
3670 warning("crit_sect initialization failed in %s: %d\n", __FILE__, __LINE__);
3671 } else if (OrderAccess::load_acquire(&process_exiting) == 0) {
3672 if (what != EPT_THREAD) {
3673 // Atomically set process_exiting before the critical section
3674 // to increase the visibility between racing threads.
3675 Atomic::cmpxchg(GetCurrentThreadId(), &process_exiting, (DWORD)0);
3676 }
3677 EnterCriticalSection(&crit_sect);
3678
3679 if (what == EPT_THREAD && OrderAccess::load_acquire(&process_exiting) == 0) {
3680 // Remove from the array those handles of the threads that have completed exiting.
3681 for (i = 0, j = 0; i < handle_count; ++i) {
3682 res = WaitForSingleObject(handles[i], 0 /* don't wait */);
3683 if (res == WAIT_TIMEOUT) {
3684 handles[j++] = handles[i];
3685 } else {
3686 if (res == WAIT_FAILED) {
3687 warning("WaitForSingleObject failed (%u) in %s: %d\n",
3688 GetLastError(), __FILE__, __LINE__);
3689 }
3690 // Don't keep the handle, if we failed waiting for it.
3691 CloseHandle(handles[i]);
3692 }
3693 }
3694
3695 // If there's no free slot in the array of the kept handles, we'll have to
3696 // wait until at least one thread completes exiting.
3697 if ((handle_count = j) == MAXIMUM_THREADS_TO_KEEP) {
3698 // Raise the priority of the oldest exiting thread to increase its chances
3699 // to complete sooner.
3700 SetThreadPriority(handles[0], THREAD_PRIORITY_ABOVE_NORMAL);
3701 res = WaitForMultipleObjects(MAXIMUM_WAIT_OBJECTS, handles, FALSE, EXIT_TIMEOUT);
3702 if (res >= WAIT_OBJECT_0 && res < (WAIT_OBJECT_0 + MAXIMUM_WAIT_OBJECTS)) {
3703 i = (res - WAIT_OBJECT_0);
3704 handle_count = MAXIMUM_THREADS_TO_KEEP - 1;
3705 for (; i < handle_count; ++i) {
3706 handles[i] = handles[i + 1];
3707 }
3708 } else {
3709 warning("WaitForMultipleObjects %s (%u) in %s: %d\n",
3710 (res == WAIT_FAILED ? "failed" : "timed out"),
3711 GetLastError(), __FILE__, __LINE__);
3712 // Don't keep handles, if we failed waiting for them.
3713 for (i = 0; i < MAXIMUM_THREADS_TO_KEEP; ++i) {
3714 CloseHandle(handles[i]);
3715 }
3716 handle_count = 0;
3717 }
3718 }
3719
3720 // Store a duplicate of the current thread handle in the array of handles.
3721 hproc = GetCurrentProcess();
3722 hthr = GetCurrentThread();
3723 if (!DuplicateHandle(hproc, hthr, hproc, &handles[handle_count],
3724 0, FALSE, DUPLICATE_SAME_ACCESS)) {
3725 warning("DuplicateHandle failed (%u) in %s: %d\n",
3726 GetLastError(), __FILE__, __LINE__);
3727
3728 // We can't register this thread (no more handles) so this thread
3729 // may be racing with a thread that is calling exit(). If the thread
3730 // that is calling exit() has managed to set the process_exiting
3731 // flag, then this thread will be caught in the SuspendThread()
3732 // infinite loop below which closes that race. A small timing
3733 // window remains before the process_exiting flag is set, but it
3734 // is only exposed when we are out of handles.
3735 } else {
3736 ++handle_count;
3737 registered = true;
3738
3739 // The current exiting thread has stored its handle in the array, and now
3740 // should leave the critical section before calling _endthreadex().
3741 }
3742
3743 } else if (what != EPT_THREAD && handle_count > 0) {
3744 jlong start_time, finish_time, timeout_left;
3745 // Before ending the process, make sure all the threads that had called
3746 // _endthreadex() completed.
3747
3748 // Set the priority level of the current thread to the same value as
3749 // the priority level of exiting threads.
3750 // This is to ensure it will be given a fair chance to execute if
3751 // the timeout expires.
3752 hthr = GetCurrentThread();
3753 SetThreadPriority(hthr, THREAD_PRIORITY_ABOVE_NORMAL);
3754 start_time = os::javaTimeNanos();
3755 finish_time = start_time + ((jlong)EXIT_TIMEOUT * 1000000L);
3756 for (i = 0; ; ) {
3757 int portion_count = handle_count - i;
3758 if (portion_count > MAXIMUM_WAIT_OBJECTS) {
3759 portion_count = MAXIMUM_WAIT_OBJECTS;
3760 }
3761 for (j = 0; j < portion_count; ++j) {
3762 SetThreadPriority(handles[i + j], THREAD_PRIORITY_ABOVE_NORMAL);
3763 }
3764 timeout_left = (finish_time - start_time) / 1000000L;
3765 if (timeout_left < 0) {
3766 timeout_left = 0;
3767 }
3768 res = WaitForMultipleObjects(portion_count, handles + i, TRUE, timeout_left);
3769 if (res == WAIT_FAILED || res == WAIT_TIMEOUT) {
3770 warning("WaitForMultipleObjects %s (%u) in %s: %d\n",
3771 (res == WAIT_FAILED ? "failed" : "timed out"),
3772 GetLastError(), __FILE__, __LINE__);
3773 // Reset portion_count so we close the remaining
3774 // handles due to this error.
3775 portion_count = handle_count - i;
3776 }
3777 for (j = 0; j < portion_count; ++j) {
3778 CloseHandle(handles[i + j]);
3779 }
3780 if ((i += portion_count) >= handle_count) {
3781 break;
3782 }
3783 start_time = os::javaTimeNanos();
3784 }
3785 handle_count = 0;
3786 }
3787
3788 LeaveCriticalSection(&crit_sect);
3789 }
3790
3791 if (!registered &&
3792 OrderAccess::load_acquire(&process_exiting) != 0 &&
3793 process_exiting != GetCurrentThreadId()) {
3794 // Some other thread is about to call exit(), so we don't let
3795 // the current unregistered thread proceed to exit() or _endthreadex()
3796 while (true) {
3797 SuspendThread(GetCurrentThread());
3798 // Avoid busy-wait loop, if SuspendThread() failed.
3799 Sleep(EXIT_TIMEOUT);
3800 }
3801 }
3802 }
3803
3804 // We are here if either
3805 // - there's no 'race at exit' bug on this OS release;
3806 // - initialization of the critical section failed (unlikely);
3807 // - the current thread has registered itself and left the critical section;
3808 // - the process-exiting thread has raised the flag and left the critical section.
3809 if (what == EPT_THREAD) {
3810 _endthreadex((unsigned)exit_code);
3811 } else if (what == EPT_PROCESS) {
3812 ::exit(exit_code);
3813 } else {
3814 _exit(exit_code);
3815 }
3816
3817 // Should not reach here
3818 return exit_code;
3819 }
3820
3821 #undef EXIT_TIMEOUT
3822
3823 void os::win32::setmode_streams() {
3824 _setmode(_fileno(stdin), _O_BINARY);
3825 _setmode(_fileno(stdout), _O_BINARY);
3826 _setmode(_fileno(stderr), _O_BINARY);
3827 }
3828
3829
3830 bool os::is_debugger_attached() {
3831 return IsDebuggerPresent() ? true : false;
3832 }
3833
3834
3835 void os::wait_for_keypress_at_exit(void) {
3836 if (PauseAtExit) {
3837 fprintf(stderr, "Press any key to continue...\n");
3838 fgetc(stdin);
3839 }
3840 }
3841
3842
3843 bool os::message_box(const char* title, const char* message) {
3844 int result = MessageBox(NULL, message, title,
3845 MB_YESNO | MB_ICONERROR | MB_SYSTEMMODAL | MB_DEFAULT_DESKTOP_ONLY);
3846 return result == IDYES;
3847 }
3848
3849 #ifndef PRODUCT
3850 #ifndef _WIN64
3851 // Helpers to check whether NX protection is enabled
3852 int nx_exception_filter(_EXCEPTION_POINTERS *pex) {
3853 if (pex->ExceptionRecord->ExceptionCode == EXCEPTION_ACCESS_VIOLATION &&
3854 pex->ExceptionRecord->NumberParameters > 0 &&
3855 pex->ExceptionRecord->ExceptionInformation[0] ==
3856 EXCEPTION_INFO_EXEC_VIOLATION) {
3857 return EXCEPTION_EXECUTE_HANDLER;
3858 }
3859 return EXCEPTION_CONTINUE_SEARCH;
3860 }
3861
3862 void nx_check_protection() {
3863 // If NX is enabled we'll get an exception calling into code on the stack
3864 char code[] = { (char)0xC3 }; // ret
3865 void *code_ptr = (void *)code;
3866 __try {
3867 __asm call code_ptr
3868 } __except(nx_exception_filter((_EXCEPTION_POINTERS*)_exception_info())) {
3869 tty->print_raw_cr("NX protection detected.");
3870 }
3871 }
3872 #endif // _WIN64
3873 #endif // PRODUCT
3874
3875 // This is called _before_ the global arguments have been parsed
3876 void os::init(void) {
3877 _initial_pid = _getpid();
3878
3879 init_random(1234567);
3880
3881 win32::initialize_system_info();
3882 win32::setmode_streams();
3883 init_page_sizes((size_t) win32::vm_page_size());
3884
3885 // This may be overridden later when argument processing is done.
3886 FLAG_SET_ERGO(bool, UseLargePagesIndividualAllocation, false);
3887
3888 // Initialize main_process and main_thread
3889 main_process = GetCurrentProcess(); // Remember main_process is a pseudo handle
3890 if (!DuplicateHandle(main_process, GetCurrentThread(), main_process,
3891 &main_thread, THREAD_ALL_ACCESS, false, 0)) {
3892 fatal("DuplicateHandle failed\n");
3893 }
3894 main_thread_id = (int) GetCurrentThreadId();
3895
3896 // initialize fast thread access - only used for 32-bit
3897 win32::initialize_thread_ptr_offset();
3898 }
3899
3900 // To install functions for atexit processing
3901 extern "C" {
3902 static void perfMemory_exit_helper() {
3903 perfMemory_exit();
3904 }
3905 }
3906
3907 static jint initSock();
3908
3909 // this is called _after_ the global arguments have been parsed
3910 jint os::init_2(void) {
3911 // Allocate a single page and mark it as readable for safepoint polling
3912 address polling_page = (address)VirtualAlloc(NULL, os::vm_page_size(), MEM_RESERVE, PAGE_READONLY);
3913 guarantee(polling_page != NULL, "Reserve Failed for polling page");
3914
3915 address return_page = (address)VirtualAlloc(polling_page, os::vm_page_size(), MEM_COMMIT, PAGE_READONLY);
3916 guarantee(return_page != NULL, "Commit Failed for polling page");
3917
3918 os::set_polling_page(polling_page);
3919 log_info(os)("SafePoint Polling address: " INTPTR_FORMAT, p2i(polling_page));
3920
3921 if (!UseMembar) {
3922 address mem_serialize_page = (address)VirtualAlloc(NULL, os::vm_page_size(), MEM_RESERVE, PAGE_READWRITE);
3923 guarantee(mem_serialize_page != NULL, "Reserve Failed for memory serialize page");
3924
3925 return_page = (address)VirtualAlloc(mem_serialize_page, os::vm_page_size(), MEM_COMMIT, PAGE_READWRITE);
3926 guarantee(return_page != NULL, "Commit Failed for memory serialize page");
3927
3928 os::set_memory_serialize_page(mem_serialize_page);
3929 log_info(os)("Memory Serialize Page address: " INTPTR_FORMAT, p2i(mem_serialize_page));
3930 }
3931
3932 // Setup Windows Exceptions
3933
3934 // for debugging float code generation bugs
3935 if (ForceFloatExceptions) {
3936 #ifndef _WIN64
3937 static long fp_control_word = 0;
3938 __asm { fstcw fp_control_word }
3939 // see Intel PPro Manual, Vol. 2, p 7-16
3940 const long precision = 0x20;
3941 const long underflow = 0x10;
3942 const long overflow = 0x08;
3943 const long zero_div = 0x04;
3944 const long denorm = 0x02;
3945 const long invalid = 0x01;
3946 fp_control_word |= invalid;
3947 __asm { fldcw fp_control_word }
3948 #endif
3949 }
3950
3951 // If stack_commit_size is 0, windows will reserve the default size,
3952 // but only commit a small portion of it.
3953 size_t stack_commit_size = align_up(ThreadStackSize*K, os::vm_page_size());
3954 size_t default_reserve_size = os::win32::default_stack_size();
3955 size_t actual_reserve_size = stack_commit_size;
3956 if (stack_commit_size < default_reserve_size) {
3957 // If stack_commit_size == 0, we want this too
3958 actual_reserve_size = default_reserve_size;
3959 }
3960
3961 // Check minimum allowable stack size for thread creation and to initialize
3962 // the java system classes, including StackOverflowError - depends on page
3963 // size. Add two 4K pages for compiler2 recursion in main thread.
3964 // Add in 4*BytesPerWord 4K pages to account for VM stack during
3965 // class initialization depending on 32 or 64 bit VM.
3966 size_t min_stack_allowed =
3967 (size_t)(JavaThread::stack_guard_zone_size() +
3968 JavaThread::stack_shadow_zone_size() +
3969 (4*BytesPerWord COMPILER2_PRESENT(+2)) * 4 * K);
3970
3971 min_stack_allowed = align_up(min_stack_allowed, os::vm_page_size());
3972
3973 if (actual_reserve_size < min_stack_allowed) {
3974 tty->print_cr("\nThe Java thread stack size specified is too small. "
3975 "Specify at least %dk",
3976 min_stack_allowed / K);
3977 return JNI_ERR;
3978 }
3979
3980 JavaThread::set_stack_size_at_create(stack_commit_size);
3981
3982 // Calculate theoretical max. size of Threads to guard gainst artifical
3983 // out-of-memory situations, where all available address-space has been
3984 // reserved by thread stacks.
3985 assert(actual_reserve_size != 0, "Must have a stack");
3986
3987 // Calculate the thread limit when we should start doing Virtual Memory
3988 // banging. Currently when the threads will have used all but 200Mb of space.
3989 //
3990 // TODO: consider performing a similar calculation for commit size instead
3991 // as reserve size, since on a 64-bit platform we'll run into that more
3992 // often than running out of virtual memory space. We can use the
3993 // lower value of the two calculations as the os_thread_limit.
3994 size_t max_address_space = ((size_t)1 << (BitsPerWord - 1)) - (200 * K * K);
3995 win32::_os_thread_limit = (intx)(max_address_space / actual_reserve_size);
3996
3997 // at exit methods are called in the reverse order of their registration.
3998 // there is no limit to the number of functions registered. atexit does
3999 // not set errno.
4000
4001 if (PerfAllowAtExitRegistration) {
4002 // only register atexit functions if PerfAllowAtExitRegistration is set.
4003 // atexit functions can be delayed until process exit time, which
4004 // can be problematic for embedded VM situations. Embedded VMs should
4005 // call DestroyJavaVM() to assure that VM resources are released.
4006
4007 // note: perfMemory_exit_helper atexit function may be removed in
4008 // the future if the appropriate cleanup code can be added to the
4009 // VM_Exit VMOperation's doit method.
4010 if (atexit(perfMemory_exit_helper) != 0) {
4011 warning("os::init_2 atexit(perfMemory_exit_helper) failed");
4012 }
4013 }
4014
4015 #ifndef _WIN64
4016 // Print something if NX is enabled (win32 on AMD64)
4017 NOT_PRODUCT(if (PrintMiscellaneous && Verbose) nx_check_protection());
4018 #endif
4019
4020 // initialize thread priority policy
4021 prio_init();
4022
4023 if (UseNUMA && !ForceNUMA) {
4024 UseNUMA = false; // We don't fully support this yet
4025 }
4026
4027 if (UseNUMAInterleaving) {
4028 // first check whether this Windows OS supports VirtualAllocExNuma, if not ignore this flag
4029 bool success = numa_interleaving_init();
4030 if (!success) UseNUMAInterleaving = false;
4031 }
4032
4033 if (initSock() != JNI_OK) {
4034 return JNI_ERR;
4035 }
4036
4037 SymbolEngine::recalc_search_path();
4038
4039 return JNI_OK;
4040 }
4041
4042 // Mark the polling page as unreadable
4043 void os::make_polling_page_unreadable(void) {
4044 DWORD old_status;
4045 if (!VirtualProtect((char *)_polling_page, os::vm_page_size(),
4046 PAGE_NOACCESS, &old_status)) {
4047 fatal("Could not disable polling page");
4048 }
4049 }
4050
4051 // Mark the polling page as readable
4052 void os::make_polling_page_readable(void) {
4053 DWORD old_status;
4054 if (!VirtualProtect((char *)_polling_page, os::vm_page_size(),
4055 PAGE_READONLY, &old_status)) {
4056 fatal("Could not enable polling page");
4057 }
4058 }
4059
4060
4061 int os::stat(const char *path, struct stat *sbuf) {
4062 char pathbuf[MAX_PATH];
4063 if (strlen(path) > MAX_PATH - 1) {
4064 errno = ENAMETOOLONG;
4065 return -1;
4066 }
4067 os::native_path(strcpy(pathbuf, path));
4068 int ret = ::stat(pathbuf, sbuf);
4069 if (sbuf != NULL && UseUTCFileTimestamp) {
4070 // Fix for 6539723. st_mtime returned from stat() is dependent on
4071 // the system timezone and so can return different values for the
4072 // same file if/when daylight savings time changes. This adjustment
4073 // makes sure the same timestamp is returned regardless of the TZ.
4074 //
4075 // See:
4076 // http://msdn.microsoft.com/library/
4077 // default.asp?url=/library/en-us/sysinfo/base/
4078 // time_zone_information_str.asp
4079 // and
4080 // http://msdn.microsoft.com/library/default.asp?url=
4081 // /library/en-us/sysinfo/base/settimezoneinformation.asp
4082 //
4083 // NOTE: there is a insidious bug here: If the timezone is changed
4084 // after the call to stat() but before 'GetTimeZoneInformation()', then
4085 // the adjustment we do here will be wrong and we'll return the wrong
4086 // value (which will likely end up creating an invalid class data
4087 // archive). Absent a better API for this, or some time zone locking
4088 // mechanism, we'll have to live with this risk.
4089 TIME_ZONE_INFORMATION tz;
4090 DWORD tzid = GetTimeZoneInformation(&tz);
4091 int daylightBias =
4092 (tzid == TIME_ZONE_ID_DAYLIGHT) ? tz.DaylightBias : tz.StandardBias;
4093 sbuf->st_mtime += (tz.Bias + daylightBias) * 60;
4094 }
4095 return ret;
4096 }
4097
4098
4099 #define FT2INT64(ft) \
4100 ((jlong)((jlong)(ft).dwHighDateTime << 32 | (julong)(ft).dwLowDateTime))
4101
4102
4103 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
4104 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
4105 // of a thread.
4106 //
4107 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
4108 // the fast estimate available on the platform.
4109
4110 // current_thread_cpu_time() is not optimized for Windows yet
4111 jlong os::current_thread_cpu_time() {
4112 // return user + sys since the cost is the same
4113 return os::thread_cpu_time(Thread::current(), true /* user+sys */);
4114 }
4115
4116 jlong os::thread_cpu_time(Thread* thread) {
4117 // consistent with what current_thread_cpu_time() returns.
4118 return os::thread_cpu_time(thread, true /* user+sys */);
4119 }
4120
4121 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
4122 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
4123 }
4124
4125 jlong os::thread_cpu_time(Thread* thread, bool user_sys_cpu_time) {
4126 // This code is copy from clasic VM -> hpi::sysThreadCPUTime
4127 // If this function changes, os::is_thread_cpu_time_supported() should too
4128 FILETIME CreationTime;
4129 FILETIME ExitTime;
4130 FILETIME KernelTime;
4131 FILETIME UserTime;
4132
4133 if (GetThreadTimes(thread->osthread()->thread_handle(), &CreationTime,
4134 &ExitTime, &KernelTime, &UserTime) == 0) {
4135 return -1;
4136 } else if (user_sys_cpu_time) {
4137 return (FT2INT64(UserTime) + FT2INT64(KernelTime)) * 100;
4138 } else {
4139 return FT2INT64(UserTime) * 100;
4140 }
4141 }
4142
4143 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4144 info_ptr->max_value = ALL_64_BITS; // the max value -- all 64 bits
4145 info_ptr->may_skip_backward = false; // GetThreadTimes returns absolute time
4146 info_ptr->may_skip_forward = false; // GetThreadTimes returns absolute time
4147 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4148 }
4149
4150 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4151 info_ptr->max_value = ALL_64_BITS; // the max value -- all 64 bits
4152 info_ptr->may_skip_backward = false; // GetThreadTimes returns absolute time
4153 info_ptr->may_skip_forward = false; // GetThreadTimes returns absolute time
4154 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4155 }
4156
4157 bool os::is_thread_cpu_time_supported() {
4158 // see os::thread_cpu_time
4159 FILETIME CreationTime;
4160 FILETIME ExitTime;
4161 FILETIME KernelTime;
4162 FILETIME UserTime;
4163
4164 if (GetThreadTimes(GetCurrentThread(), &CreationTime, &ExitTime,
4165 &KernelTime, &UserTime) == 0) {
4166 return false;
4167 } else {
4168 return true;
4169 }
4170 }
4171
4172 // Windows does't provide a loadavg primitive so this is stubbed out for now.
4173 // It does have primitives (PDH API) to get CPU usage and run queue length.
4174 // "\\Processor(_Total)\\% Processor Time", "\\System\\Processor Queue Length"
4175 // If we wanted to implement loadavg on Windows, we have a few options:
4176 //
4177 // a) Query CPU usage and run queue length and "fake" an answer by
4178 // returning the CPU usage if it's under 100%, and the run queue
4179 // length otherwise. It turns out that querying is pretty slow
4180 // on Windows, on the order of 200 microseconds on a fast machine.
4181 // Note that on the Windows the CPU usage value is the % usage
4182 // since the last time the API was called (and the first call
4183 // returns 100%), so we'd have to deal with that as well.
4184 //
4185 // b) Sample the "fake" answer using a sampling thread and store
4186 // the answer in a global variable. The call to loadavg would
4187 // just return the value of the global, avoiding the slow query.
4188 //
4189 // c) Sample a better answer using exponential decay to smooth the
4190 // value. This is basically the algorithm used by UNIX kernels.
4191 //
4192 // Note that sampling thread starvation could affect both (b) and (c).
4193 int os::loadavg(double loadavg[], int nelem) {
4194 return -1;
4195 }
4196
4197
4198 // DontYieldALot=false by default: dutifully perform all yields as requested by JVM_Yield()
4199 bool os::dont_yield() {
4200 return DontYieldALot;
4201 }
4202
4203 // This method is a slightly reworked copy of JDK's sysOpen
4204 // from src/windows/hpi/src/sys_api_md.c
4205
4206 int os::open(const char *path, int oflag, int mode) {
4207 char pathbuf[MAX_PATH];
4208
4209 if (strlen(path) > MAX_PATH - 1) {
4210 errno = ENAMETOOLONG;
4211 return -1;
4212 }
4213 os::native_path(strcpy(pathbuf, path));
4214 return ::open(pathbuf, oflag | O_BINARY | O_NOINHERIT, mode);
4215 }
4216
4217 FILE* os::open(int fd, const char* mode) {
4218 return ::_fdopen(fd, mode);
4219 }
4220
4221 // Is a (classpath) directory empty?
4222 bool os::dir_is_empty(const char* path) {
4223 WIN32_FIND_DATA fd;
4224 HANDLE f = FindFirstFile(path, &fd);
4225 if (f == INVALID_HANDLE_VALUE) {
4226 return true;
4227 }
4228 FindClose(f);
4229 return false;
4230 }
4231
4232 // create binary file, rewriting existing file if required
4233 int os::create_binary_file(const char* path, bool rewrite_existing) {
4234 int oflags = _O_CREAT | _O_WRONLY | _O_BINARY;
4235 if (!rewrite_existing) {
4236 oflags |= _O_EXCL;
4237 }
4238 return ::open(path, oflags, _S_IREAD | _S_IWRITE);
4239 }
4240
4241 // return current position of file pointer
4242 jlong os::current_file_offset(int fd) {
4243 return (jlong)::_lseeki64(fd, (__int64)0L, SEEK_CUR);
4244 }
4245
4246 // move file pointer to the specified offset
4247 jlong os::seek_to_file_offset(int fd, jlong offset) {
4248 return (jlong)::_lseeki64(fd, (__int64)offset, SEEK_SET);
4249 }
4250
4251
4252 jlong os::lseek(int fd, jlong offset, int whence) {
4253 return (jlong) ::_lseeki64(fd, offset, whence);
4254 }
4255
4256 size_t os::read_at(int fd, void *buf, unsigned int nBytes, jlong offset) {
4257 OVERLAPPED ov;
4258 DWORD nread;
4259 BOOL result;
4260
4261 ZeroMemory(&ov, sizeof(ov));
4262 ov.Offset = (DWORD)offset;
4263 ov.OffsetHigh = (DWORD)(offset >> 32);
4264
4265 HANDLE h = (HANDLE)::_get_osfhandle(fd);
4266
4267 result = ReadFile(h, (LPVOID)buf, nBytes, &nread, &ov);
4268
4269 return result ? nread : 0;
4270 }
4271
4272
4273 // This method is a slightly reworked copy of JDK's sysNativePath
4274 // from src/windows/hpi/src/path_md.c
4275
4276 // Convert a pathname to native format. On win32, this involves forcing all
4277 // separators to be '\\' rather than '/' (both are legal inputs, but Win95
4278 // sometimes rejects '/') and removing redundant separators. The input path is
4279 // assumed to have been converted into the character encoding used by the local
4280 // system. Because this might be a double-byte encoding, care is taken to
4281 // treat double-byte lead characters correctly.
4282 //
4283 // This procedure modifies the given path in place, as the result is never
4284 // longer than the original. There is no error return; this operation always
4285 // succeeds.
4286 char * os::native_path(char *path) {
4287 char *src = path, *dst = path, *end = path;
4288 char *colon = NULL; // If a drive specifier is found, this will
4289 // point to the colon following the drive letter
4290
4291 // Assumption: '/', '\\', ':', and drive letters are never lead bytes
4292 assert(((!::IsDBCSLeadByte('/')) && (!::IsDBCSLeadByte('\\'))
4293 && (!::IsDBCSLeadByte(':'))), "Illegal lead byte");
4294
4295 // Check for leading separators
4296 #define isfilesep(c) ((c) == '/' || (c) == '\\')
4297 while (isfilesep(*src)) {
4298 src++;
4299 }
4300
4301 if (::isalpha(*src) && !::IsDBCSLeadByte(*src) && src[1] == ':') {
4302 // Remove leading separators if followed by drive specifier. This
4303 // hack is necessary to support file URLs containing drive
4304 // specifiers (e.g., "file://c:/path"). As a side effect,
4305 // "/c:/path" can be used as an alternative to "c:/path".
4306 *dst++ = *src++;
4307 colon = dst;
4308 *dst++ = ':';
4309 src++;
4310 } else {
4311 src = path;
4312 if (isfilesep(src[0]) && isfilesep(src[1])) {
4313 // UNC pathname: Retain first separator; leave src pointed at
4314 // second separator so that further separators will be collapsed
4315 // into the second separator. The result will be a pathname
4316 // beginning with "\\\\" followed (most likely) by a host name.
4317 src = dst = path + 1;
4318 path[0] = '\\'; // Force first separator to '\\'
4319 }
4320 }
4321
4322 end = dst;
4323
4324 // Remove redundant separators from remainder of path, forcing all
4325 // separators to be '\\' rather than '/'. Also, single byte space
4326 // characters are removed from the end of the path because those
4327 // are not legal ending characters on this operating system.
4328 //
4329 while (*src != '\0') {
4330 if (isfilesep(*src)) {
4331 *dst++ = '\\'; src++;
4332 while (isfilesep(*src)) src++;
4333 if (*src == '\0') {
4334 // Check for trailing separator
4335 end = dst;
4336 if (colon == dst - 2) break; // "z:\\"
4337 if (dst == path + 1) break; // "\\"
4338 if (dst == path + 2 && isfilesep(path[0])) {
4339 // "\\\\" is not collapsed to "\\" because "\\\\" marks the
4340 // beginning of a UNC pathname. Even though it is not, by
4341 // itself, a valid UNC pathname, we leave it as is in order
4342 // to be consistent with the path canonicalizer as well
4343 // as the win32 APIs, which treat this case as an invalid
4344 // UNC pathname rather than as an alias for the root
4345 // directory of the current drive.
4346 break;
4347 }
4348 end = --dst; // Path does not denote a root directory, so
4349 // remove trailing separator
4350 break;
4351 }
4352 end = dst;
4353 } else {
4354 if (::IsDBCSLeadByte(*src)) { // Copy a double-byte character
4355 *dst++ = *src++;
4356 if (*src) *dst++ = *src++;
4357 end = dst;
4358 } else { // Copy a single-byte character
4359 char c = *src++;
4360 *dst++ = c;
4361 // Space is not a legal ending character
4362 if (c != ' ') end = dst;
4363 }
4364 }
4365 }
4366
4367 *end = '\0';
4368
4369 // For "z:", add "." to work around a bug in the C runtime library
4370 if (colon == dst - 1) {
4371 path[2] = '.';
4372 path[3] = '\0';
4373 }
4374
4375 return path;
4376 }
4377
4378 // This code is a copy of JDK's sysSetLength
4379 // from src/windows/hpi/src/sys_api_md.c
4380
4381 int os::ftruncate(int fd, jlong length) {
4382 HANDLE h = (HANDLE)::_get_osfhandle(fd);
4383 long high = (long)(length >> 32);
4384 DWORD ret;
4385
4386 if (h == (HANDLE)(-1)) {
4387 return -1;
4388 }
4389
4390 ret = ::SetFilePointer(h, (long)(length), &high, FILE_BEGIN);
4391 if ((ret == 0xFFFFFFFF) && (::GetLastError() != NO_ERROR)) {
4392 return -1;
4393 }
4394
4395 if (::SetEndOfFile(h) == FALSE) {
4396 return -1;
4397 }
4398
4399 return 0;
4400 }
4401
4402 int os::get_fileno(FILE* fp) {
4403 return _fileno(fp);
4404 }
4405
4406 // This code is a copy of JDK's sysSync
4407 // from src/windows/hpi/src/sys_api_md.c
4408 // except for the legacy workaround for a bug in Win 98
4409
4410 int os::fsync(int fd) {
4411 HANDLE handle = (HANDLE)::_get_osfhandle(fd);
4412
4413 if ((!::FlushFileBuffers(handle)) &&
4414 (GetLastError() != ERROR_ACCESS_DENIED)) {
4415 // from winerror.h
4416 return -1;
4417 }
4418 return 0;
4419 }
4420
4421 static int nonSeekAvailable(int, long *);
4422 static int stdinAvailable(int, long *);
4423
4424 #define S_ISCHR(mode) (((mode) & _S_IFCHR) == _S_IFCHR)
4425 #define S_ISFIFO(mode) (((mode) & _S_IFIFO) == _S_IFIFO)
4426
4427 // This code is a copy of JDK's sysAvailable
4428 // from src/windows/hpi/src/sys_api_md.c
4429
4430 int os::available(int fd, jlong *bytes) {
4431 jlong cur, end;
4432 struct _stati64 stbuf64;
4433
4434 if (::_fstati64(fd, &stbuf64) >= 0) {
4435 int mode = stbuf64.st_mode;
4436 if (S_ISCHR(mode) || S_ISFIFO(mode)) {
4437 int ret;
4438 long lpbytes;
4439 if (fd == 0) {
4440 ret = stdinAvailable(fd, &lpbytes);
4441 } else {
4442 ret = nonSeekAvailable(fd, &lpbytes);
4443 }
4444 (*bytes) = (jlong)(lpbytes);
4445 return ret;
4446 }
4447 if ((cur = ::_lseeki64(fd, 0L, SEEK_CUR)) == -1) {
4448 return FALSE;
4449 } else if ((end = ::_lseeki64(fd, 0L, SEEK_END)) == -1) {
4450 return FALSE;
4451 } else if (::_lseeki64(fd, cur, SEEK_SET) == -1) {
4452 return FALSE;
4453 }
4454 *bytes = end - cur;
4455 return TRUE;
4456 } else {
4457 return FALSE;
4458 }
4459 }
4460
4461 void os::flockfile(FILE* fp) {
4462 _lock_file(fp);
4463 }
4464
4465 void os::funlockfile(FILE* fp) {
4466 _unlock_file(fp);
4467 }
4468
4469 // This code is a copy of JDK's nonSeekAvailable
4470 // from src/windows/hpi/src/sys_api_md.c
4471
4472 static int nonSeekAvailable(int fd, long *pbytes) {
4473 // This is used for available on non-seekable devices
4474 // (like both named and anonymous pipes, such as pipes
4475 // connected to an exec'd process).
4476 // Standard Input is a special case.
4477 HANDLE han;
4478
4479 if ((han = (HANDLE) ::_get_osfhandle(fd)) == (HANDLE)(-1)) {
4480 return FALSE;
4481 }
4482
4483 if (! ::PeekNamedPipe(han, NULL, 0, NULL, (LPDWORD)pbytes, NULL)) {
4484 // PeekNamedPipe fails when at EOF. In that case we
4485 // simply make *pbytes = 0 which is consistent with the
4486 // behavior we get on Solaris when an fd is at EOF.
4487 // The only alternative is to raise an Exception,
4488 // which isn't really warranted.
4489 //
4490 if (::GetLastError() != ERROR_BROKEN_PIPE) {
4491 return FALSE;
4492 }
4493 *pbytes = 0;
4494 }
4495 return TRUE;
4496 }
4497
4498 #define MAX_INPUT_EVENTS 2000
4499
4500 // This code is a copy of JDK's stdinAvailable
4501 // from src/windows/hpi/src/sys_api_md.c
4502
4503 static int stdinAvailable(int fd, long *pbytes) {
4504 HANDLE han;
4505 DWORD numEventsRead = 0; // Number of events read from buffer
4506 DWORD numEvents = 0; // Number of events in buffer
4507 DWORD i = 0; // Loop index
4508 DWORD curLength = 0; // Position marker
4509 DWORD actualLength = 0; // Number of bytes readable
4510 BOOL error = FALSE; // Error holder
4511 INPUT_RECORD *lpBuffer; // Pointer to records of input events
4512
4513 if ((han = ::GetStdHandle(STD_INPUT_HANDLE)) == INVALID_HANDLE_VALUE) {
4514 return FALSE;
4515 }
4516
4517 // Construct an array of input records in the console buffer
4518 error = ::GetNumberOfConsoleInputEvents(han, &numEvents);
4519 if (error == 0) {
4520 return nonSeekAvailable(fd, pbytes);
4521 }
4522
4523 // lpBuffer must fit into 64K or else PeekConsoleInput fails
4524 if (numEvents > MAX_INPUT_EVENTS) {
4525 numEvents = MAX_INPUT_EVENTS;
4526 }
4527
4528 lpBuffer = (INPUT_RECORD *)os::malloc(numEvents * sizeof(INPUT_RECORD), mtInternal);
4529 if (lpBuffer == NULL) {
4530 return FALSE;
4531 }
4532
4533 error = ::PeekConsoleInput(han, lpBuffer, numEvents, &numEventsRead);
4534 if (error == 0) {
4535 os::free(lpBuffer);
4536 return FALSE;
4537 }
4538
4539 // Examine input records for the number of bytes available
4540 for (i=0; i<numEvents; i++) {
4541 if (lpBuffer[i].EventType == KEY_EVENT) {
4542
4543 KEY_EVENT_RECORD *keyRecord = (KEY_EVENT_RECORD *)
4544 &(lpBuffer[i].Event);
4545 if (keyRecord->bKeyDown == TRUE) {
4546 CHAR *keyPressed = (CHAR *) &(keyRecord->uChar);
4547 curLength++;
4548 if (*keyPressed == '\r') {
4549 actualLength = curLength;
4550 }
4551 }
4552 }
4553 }
4554
4555 if (lpBuffer != NULL) {
4556 os::free(lpBuffer);
4557 }
4558
4559 *pbytes = (long) actualLength;
4560 return TRUE;
4561 }
4562
4563 // Map a block of memory.
4564 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
4565 char *addr, size_t bytes, bool read_only,
4566 bool allow_exec) {
4567 HANDLE hFile;
4568 char* base;
4569
4570 hFile = CreateFile(file_name, GENERIC_READ, FILE_SHARE_READ, NULL,
4571 OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
4572 if (hFile == NULL) {
4573 log_info(os)("CreateFile() failed: GetLastError->%ld.", GetLastError());
4574 return NULL;
4575 }
4576
4577 if (allow_exec) {
4578 // CreateFileMapping/MapViewOfFileEx can't map executable memory
4579 // unless it comes from a PE image (which the shared archive is not.)
4580 // Even VirtualProtect refuses to give execute access to mapped memory
4581 // that was not previously executable.
4582 //
4583 // Instead, stick the executable region in anonymous memory. Yuck.
4584 // Penalty is that ~4 pages will not be shareable - in the future
4585 // we might consider DLLizing the shared archive with a proper PE
4586 // header so that mapping executable + sharing is possible.
4587
4588 base = (char*) VirtualAlloc(addr, bytes, MEM_COMMIT | MEM_RESERVE,
4589 PAGE_READWRITE);
4590 if (base == NULL) {
4591 log_info(os)("VirtualAlloc() failed: GetLastError->%ld.", GetLastError());
4592 CloseHandle(hFile);
4593 return NULL;
4594 }
4595
4596 DWORD bytes_read;
4597 OVERLAPPED overlapped;
4598 overlapped.Offset = (DWORD)file_offset;
4599 overlapped.OffsetHigh = 0;
4600 overlapped.hEvent = NULL;
4601 // ReadFile guarantees that if the return value is true, the requested
4602 // number of bytes were read before returning.
4603 bool res = ReadFile(hFile, base, (DWORD)bytes, &bytes_read, &overlapped) != 0;
4604 if (!res) {
4605 log_info(os)("ReadFile() failed: GetLastError->%ld.", GetLastError());
4606 release_memory(base, bytes);
4607 CloseHandle(hFile);
4608 return NULL;
4609 }
4610 } else {
4611 HANDLE hMap = CreateFileMapping(hFile, NULL, PAGE_WRITECOPY, 0, 0,
4612 NULL /* file_name */);
4613 if (hMap == NULL) {
4614 log_info(os)("CreateFileMapping() failed: GetLastError->%ld.", GetLastError());
4615 CloseHandle(hFile);
4616 return NULL;
4617 }
4618
4619 DWORD access = read_only ? FILE_MAP_READ : FILE_MAP_COPY;
4620 base = (char*)MapViewOfFileEx(hMap, access, 0, (DWORD)file_offset,
4621 (DWORD)bytes, addr);
4622 if (base == NULL) {
4623 log_info(os)("MapViewOfFileEx() failed: GetLastError->%ld.", GetLastError());
4624 CloseHandle(hMap);
4625 CloseHandle(hFile);
4626 return NULL;
4627 }
4628
4629 if (CloseHandle(hMap) == 0) {
4630 log_info(os)("CloseHandle(hMap) failed: GetLastError->%ld.", GetLastError());
4631 CloseHandle(hFile);
4632 return base;
4633 }
4634 }
4635
4636 if (allow_exec) {
4637 DWORD old_protect;
4638 DWORD exec_access = read_only ? PAGE_EXECUTE_READ : PAGE_EXECUTE_READWRITE;
4639 bool res = VirtualProtect(base, bytes, exec_access, &old_protect) != 0;
4640
4641 if (!res) {
4642 log_info(os)("VirtualProtect() failed: GetLastError->%ld.", GetLastError());
4643 // Don't consider this a hard error, on IA32 even if the
4644 // VirtualProtect fails, we should still be able to execute
4645 CloseHandle(hFile);
4646 return base;
4647 }
4648 }
4649
4650 if (CloseHandle(hFile) == 0) {
4651 log_info(os)("CloseHandle(hFile) failed: GetLastError->%ld.", GetLastError());
4652 return base;
4653 }
4654
4655 return base;
4656 }
4657
4658
4659 // Remap a block of memory.
4660 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
4661 char *addr, size_t bytes, bool read_only,
4662 bool allow_exec) {
4663 // This OS does not allow existing memory maps to be remapped so we
4664 // have to unmap the memory before we remap it.
4665 if (!os::unmap_memory(addr, bytes)) {
4666 return NULL;
4667 }
4668
4669 // There is a very small theoretical window between the unmap_memory()
4670 // call above and the map_memory() call below where a thread in native
4671 // code may be able to access an address that is no longer mapped.
4672
4673 return os::map_memory(fd, file_name, file_offset, addr, bytes,
4674 read_only, allow_exec);
4675 }
4676
4677
4678 // Unmap a block of memory.
4679 // Returns true=success, otherwise false.
4680
4681 bool os::pd_unmap_memory(char* addr, size_t bytes) {
4682 MEMORY_BASIC_INFORMATION mem_info;
4683 if (VirtualQuery(addr, &mem_info, sizeof(mem_info)) == 0) {
4684 log_info(os)("VirtualQuery() failed: GetLastError->%ld.", GetLastError());
4685 return false;
4686 }
4687
4688 // Executable memory was not mapped using CreateFileMapping/MapViewOfFileEx.
4689 // Instead, executable region was allocated using VirtualAlloc(). See
4690 // pd_map_memory() above.
4691 //
4692 // The following flags should match the 'exec_access' flages used for
4693 // VirtualProtect() in pd_map_memory().
4694 if (mem_info.Protect == PAGE_EXECUTE_READ ||
4695 mem_info.Protect == PAGE_EXECUTE_READWRITE) {
4696 return pd_release_memory(addr, bytes);
4697 }
4698
4699 BOOL result = UnmapViewOfFile(addr);
4700 if (result == 0) {
4701 log_info(os)("UnmapViewOfFile() failed: GetLastError->%ld.", GetLastError());
4702 return false;
4703 }
4704 return true;
4705 }
4706
4707 void os::pause() {
4708 char filename[MAX_PATH];
4709 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
4710 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
4711 } else {
4712 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
4713 }
4714
4715 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
4716 if (fd != -1) {
4717 struct stat buf;
4718 ::close(fd);
4719 while (::stat(filename, &buf) == 0) {
4720 Sleep(100);
4721 }
4722 } else {
4723 jio_fprintf(stderr,
4724 "Could not open pause file '%s', continuing immediately.\n", filename);
4725 }
4726 }
4727
4728 Thread* os::ThreadCrashProtection::_protected_thread = NULL;
4729 os::ThreadCrashProtection* os::ThreadCrashProtection::_crash_protection = NULL;
4730 volatile intptr_t os::ThreadCrashProtection::_crash_mux = 0;
4731
4732 os::ThreadCrashProtection::ThreadCrashProtection() {
4733 }
4734
4735 // See the caveats for this class in os_windows.hpp
4736 // Protects the callback call so that raised OS EXCEPTIONS causes a jump back
4737 // into this method and returns false. If no OS EXCEPTION was raised, returns
4738 // true.
4739 // The callback is supposed to provide the method that should be protected.
4740 //
4741 bool os::ThreadCrashProtection::call(os::CrashProtectionCallback& cb) {
4742
4743 Thread::muxAcquire(&_crash_mux, "CrashProtection");
4744
4745 _protected_thread = Thread::current_or_null();
4746 assert(_protected_thread != NULL, "Cannot crash protect a NULL thread");
4747
4748 bool success = true;
4749 __try {
4750 _crash_protection = this;
4751 cb.call();
4752 } __except(EXCEPTION_EXECUTE_HANDLER) {
4753 // only for protection, nothing to do
4754 success = false;
4755 }
4756 _crash_protection = NULL;
4757 _protected_thread = NULL;
4758 Thread::muxRelease(&_crash_mux);
4759 return success;
4760 }
4761
4762 // An Event wraps a win32 "CreateEvent" kernel handle.
4763 //
4764 // We have a number of choices regarding "CreateEvent" win32 handle leakage:
4765 //
4766 // 1: When a thread dies return the Event to the EventFreeList, clear the ParkHandle
4767 // field, and call CloseHandle() on the win32 event handle. Unpark() would
4768 // need to be modified to tolerate finding a NULL (invalid) win32 event handle.
4769 // In addition, an unpark() operation might fetch the handle field, but the
4770 // event could recycle between the fetch and the SetEvent() operation.
4771 // SetEvent() would either fail because the handle was invalid, or inadvertently work,
4772 // as the win32 handle value had been recycled. In an ideal world calling SetEvent()
4773 // on an stale but recycled handle would be harmless, but in practice this might
4774 // confuse other non-Sun code, so it's not a viable approach.
4775 //
4776 // 2: Once a win32 event handle is associated with an Event, it remains associated
4777 // with the Event. The event handle is never closed. This could be construed
4778 // as handle leakage, but only up to the maximum # of threads that have been extant
4779 // at any one time. This shouldn't be an issue, as windows platforms typically
4780 // permit a process to have hundreds of thousands of open handles.
4781 //
4782 // 3: Same as (1), but periodically, at stop-the-world time, rundown the EventFreeList
4783 // and release unused handles.
4784 //
4785 // 4: Add a CRITICAL_SECTION to the Event to protect LD+SetEvent from LD;ST(null);CloseHandle.
4786 // It's not clear, however, that we wouldn't be trading one type of leak for another.
4787 //
4788 // 5. Use an RCU-like mechanism (Read-Copy Update).
4789 // Or perhaps something similar to Maged Michael's "Hazard pointers".
4790 //
4791 // We use (2).
4792 //
4793 // TODO-FIXME:
4794 // 1. Reconcile Doug's JSR166 j.u.c park-unpark with the objectmonitor implementation.
4795 // 2. Consider wrapping the WaitForSingleObject(Ex) calls in SEH try/finally blocks
4796 // to recover from (or at least detect) the dreaded Windows 841176 bug.
4797 // 3. Collapse the interrupt_event, the JSR166 parker event, and the objectmonitor ParkEvent
4798 // into a single win32 CreateEvent() handle.
4799 //
4800 // Assumption:
4801 // Only one parker can exist on an event, which is why we allocate
4802 // them per-thread. Multiple unparkers can coexist.
4803 //
4804 // _Event transitions in park()
4805 // -1 => -1 : illegal
4806 // 1 => 0 : pass - return immediately
4807 // 0 => -1 : block; then set _Event to 0 before returning
4808 //
4809 // _Event transitions in unpark()
4810 // 0 => 1 : just return
4811 // 1 => 1 : just return
4812 // -1 => either 0 or 1; must signal target thread
4813 // That is, we can safely transition _Event from -1 to either
4814 // 0 or 1.
4815 //
4816 // _Event serves as a restricted-range semaphore.
4817 // -1 : thread is blocked, i.e. there is a waiter
4818 // 0 : neutral: thread is running or ready,
4819 // could have been signaled after a wait started
4820 // 1 : signaled - thread is running or ready
4821 //
4822 // Another possible encoding of _Event would be with
4823 // explicit "PARKED" == 01b and "SIGNALED" == 10b bits.
4824 //
4825
4826 int os::PlatformEvent::park(jlong Millis) {
4827 // Transitions for _Event:
4828 // -1 => -1 : illegal
4829 // 1 => 0 : pass - return immediately
4830 // 0 => -1 : block; then set _Event to 0 before returning
4831
4832 guarantee(_ParkHandle != NULL , "Invariant");
4833 guarantee(Millis > 0 , "Invariant");
4834
4835 // CONSIDER: defer assigning a CreateEvent() handle to the Event until
4836 // the initial park() operation.
4837 // Consider: use atomic decrement instead of CAS-loop
4838
4839 int v;
4840 for (;;) {
4841 v = _Event;
4842 if (Atomic::cmpxchg(v-1, &_Event, v) == v) break;
4843 }
4844 guarantee((v == 0) || (v == 1), "invariant");
4845 if (v != 0) return OS_OK;
4846
4847 // Do this the hard way by blocking ...
4848 // TODO: consider a brief spin here, gated on the success of recent
4849 // spin attempts by this thread.
4850 //
4851 // We decompose long timeouts into series of shorter timed waits.
4852 // Evidently large timo values passed in WaitForSingleObject() are problematic on some
4853 // versions of Windows. See EventWait() for details. This may be superstition. Or not.
4854 // We trust the WAIT_TIMEOUT indication and don't track the elapsed wait time
4855 // with os::javaTimeNanos(). Furthermore, we assume that spurious returns from
4856 // ::WaitForSingleObject() caused by latent ::setEvent() operations will tend
4857 // to happen early in the wait interval. Specifically, after a spurious wakeup (rv ==
4858 // WAIT_OBJECT_0 but _Event is still < 0) we don't bother to recompute Millis to compensate
4859 // for the already waited time. This policy does not admit any new outcomes.
4860 // In the future, however, we might want to track the accumulated wait time and
4861 // adjust Millis accordingly if we encounter a spurious wakeup.
4862
4863 const int MAXTIMEOUT = 0x10000000;
4864 DWORD rv = WAIT_TIMEOUT;
4865 while (_Event < 0 && Millis > 0) {
4866 DWORD prd = Millis; // set prd = MAX (Millis, MAXTIMEOUT)
4867 if (Millis > MAXTIMEOUT) {
4868 prd = MAXTIMEOUT;
4869 }
4870 rv = ::WaitForSingleObject(_ParkHandle, prd);
4871 assert(rv == WAIT_OBJECT_0 || rv == WAIT_TIMEOUT, "WaitForSingleObject failed");
4872 if (rv == WAIT_TIMEOUT) {
4873 Millis -= prd;
4874 }
4875 }
4876 v = _Event;
4877 _Event = 0;
4878 // see comment at end of os::PlatformEvent::park() below:
4879 OrderAccess::fence();
4880 // If we encounter a nearly simultanous timeout expiry and unpark()
4881 // we return OS_OK indicating we awoke via unpark().
4882 // Implementor's license -- returning OS_TIMEOUT would be equally valid, however.
4883 return (v >= 0) ? OS_OK : OS_TIMEOUT;
4884 }
4885
4886 void os::PlatformEvent::park() {
4887 // Transitions for _Event:
4888 // -1 => -1 : illegal
4889 // 1 => 0 : pass - return immediately
4890 // 0 => -1 : block; then set _Event to 0 before returning
4891
4892 guarantee(_ParkHandle != NULL, "Invariant");
4893 // Invariant: Only the thread associated with the Event/PlatformEvent
4894 // may call park().
4895 // Consider: use atomic decrement instead of CAS-loop
4896 int v;
4897 for (;;) {
4898 v = _Event;
4899 if (Atomic::cmpxchg(v-1, &_Event, v) == v) break;
4900 }
4901 guarantee((v == 0) || (v == 1), "invariant");
4902 if (v != 0) return;
4903
4904 // Do this the hard way by blocking ...
4905 // TODO: consider a brief spin here, gated on the success of recent
4906 // spin attempts by this thread.
4907 while (_Event < 0) {
4908 DWORD rv = ::WaitForSingleObject(_ParkHandle, INFINITE);
4909 assert(rv == WAIT_OBJECT_0, "WaitForSingleObject failed");
4910 }
4911
4912 // Usually we'll find _Event == 0 at this point, but as
4913 // an optional optimization we clear it, just in case can
4914 // multiple unpark() operations drove _Event up to 1.
4915 _Event = 0;
4916 OrderAccess::fence();
4917 guarantee(_Event >= 0, "invariant");
4918 }
4919
4920 void os::PlatformEvent::unpark() {
4921 guarantee(_ParkHandle != NULL, "Invariant");
4922
4923 // Transitions for _Event:
4924 // 0 => 1 : just return
4925 // 1 => 1 : just return
4926 // -1 => either 0 or 1; must signal target thread
4927 // That is, we can safely transition _Event from -1 to either
4928 // 0 or 1.
4929 // See also: "Semaphores in Plan 9" by Mullender & Cox
4930 //
4931 // Note: Forcing a transition from "-1" to "1" on an unpark() means
4932 // that it will take two back-to-back park() calls for the owning
4933 // thread to block. This has the benefit of forcing a spurious return
4934 // from the first park() call after an unpark() call which will help
4935 // shake out uses of park() and unpark() without condition variables.
4936
4937 if (Atomic::xchg(1, &_Event) >= 0) return;
4938
4939 ::SetEvent(_ParkHandle);
4940 }
4941
4942
4943 // JSR166
4944 // -------------------------------------------------------
4945
4946 // The Windows implementation of Park is very straightforward: Basic
4947 // operations on Win32 Events turn out to have the right semantics to
4948 // use them directly. We opportunistically resuse the event inherited
4949 // from Monitor.
4950
4951 void Parker::park(bool isAbsolute, jlong time) {
4952 guarantee(_ParkEvent != NULL, "invariant");
4953 // First, demultiplex/decode time arguments
4954 if (time < 0) { // don't wait
4955 return;
4956 } else if (time == 0 && !isAbsolute) {
4957 time = INFINITE;
4958 } else if (isAbsolute) {
4959 time -= os::javaTimeMillis(); // convert to relative time
4960 if (time <= 0) { // already elapsed
4961 return;
4962 }
4963 } else { // relative
4964 time /= 1000000; // Must coarsen from nanos to millis
4965 if (time == 0) { // Wait for the minimal time unit if zero
4966 time = 1;
4967 }
4968 }
4969
4970 JavaThread* thread = JavaThread::current();
4971
4972 // Don't wait if interrupted or already triggered
4973 if (Thread::is_interrupted(thread, false) ||
4974 WaitForSingleObject(_ParkEvent, 0) == WAIT_OBJECT_0) {
4975 ResetEvent(_ParkEvent);
4976 return;
4977 } else {
4978 ThreadBlockInVM tbivm(thread);
4979 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
4980 thread->set_suspend_equivalent();
4981
4982 WaitForSingleObject(_ParkEvent, time);
4983 ResetEvent(_ParkEvent);
4984
4985 // If externally suspended while waiting, re-suspend
4986 if (thread->handle_special_suspend_equivalent_condition()) {
4987 thread->java_suspend_self();
4988 }
4989 }
4990 }
4991
4992 void Parker::unpark() {
4993 guarantee(_ParkEvent != NULL, "invariant");
4994 SetEvent(_ParkEvent);
4995 }
4996
4997 // Run the specified command in a separate process. Return its exit value,
4998 // or -1 on failure (e.g. can't create a new process).
4999 int os::fork_and_exec(char* cmd) {
5000 STARTUPINFO si;
5001 PROCESS_INFORMATION pi;
5002 DWORD exit_code;
5003
5004 char * cmd_string;
5005 char * cmd_prefix = "cmd /C ";
5006 size_t len = strlen(cmd) + strlen(cmd_prefix) + 1;
5007 cmd_string = NEW_C_HEAP_ARRAY_RETURN_NULL(char, len, mtInternal);
5008 if (cmd_string == NULL) {
5009 return -1;
5010 }
5011 cmd_string[0] = '\0';
5012 strcat(cmd_string, cmd_prefix);
5013 strcat(cmd_string, cmd);
5014
5015 // now replace all '\n' with '&'
5016 char * substring = cmd_string;
5017 while ((substring = strchr(substring, '\n')) != NULL) {
5018 substring[0] = '&';
5019 substring++;
5020 }
5021 memset(&si, 0, sizeof(si));
5022 si.cb = sizeof(si);
5023 memset(&pi, 0, sizeof(pi));
5024 BOOL rslt = CreateProcess(NULL, // executable name - use command line
5025 cmd_string, // command line
5026 NULL, // process security attribute
5027 NULL, // thread security attribute
5028 TRUE, // inherits system handles
5029 0, // no creation flags
5030 NULL, // use parent's environment block
5031 NULL, // use parent's starting directory
5032 &si, // (in) startup information
5033 &pi); // (out) process information
5034
5035 if (rslt) {
5036 // Wait until child process exits.
5037 WaitForSingleObject(pi.hProcess, INFINITE);
5038
5039 GetExitCodeProcess(pi.hProcess, &exit_code);
5040
5041 // Close process and thread handles.
5042 CloseHandle(pi.hProcess);
5043 CloseHandle(pi.hThread);
5044 } else {
5045 exit_code = -1;
5046 }
5047
5048 FREE_C_HEAP_ARRAY(char, cmd_string);
5049 return (int)exit_code;
5050 }
5051
5052 bool os::find(address addr, outputStream* st) {
5053 int offset = -1;
5054 bool result = false;
5055 char buf[256];
5056 if (os::dll_address_to_library_name(addr, buf, sizeof(buf), &offset)) {
5057 st->print(PTR_FORMAT " ", addr);
5058 if (strlen(buf) < sizeof(buf) - 1) {
5059 char* p = strrchr(buf, '\\');
5060 if (p) {
5061 st->print("%s", p + 1);
5062 } else {
5063 st->print("%s", buf);
5064 }
5065 } else {
5066 // The library name is probably truncated. Let's omit the library name.
5067 // See also JDK-8147512.
5068 }
5069 if (os::dll_address_to_function_name(addr, buf, sizeof(buf), &offset)) {
5070 st->print("::%s + 0x%x", buf, offset);
5071 }
5072 st->cr();
5073 result = true;
5074 }
5075 return result;
5076 }
5077
5078 LONG WINAPI os::win32::serialize_fault_filter(struct _EXCEPTION_POINTERS* e) {
5079 DWORD exception_code = e->ExceptionRecord->ExceptionCode;
5080
5081 if (exception_code == EXCEPTION_ACCESS_VIOLATION) {
5082 JavaThread* thread = JavaThread::current();
5083 PEXCEPTION_RECORD exceptionRecord = e->ExceptionRecord;
5084 address addr = (address) exceptionRecord->ExceptionInformation[1];
5085
5086 if (os::is_memory_serialize_page(thread, addr)) {
5087 return EXCEPTION_CONTINUE_EXECUTION;
5088 }
5089 }
5090
5091 return EXCEPTION_CONTINUE_SEARCH;
5092 }
5093
5094 // We don't build a headless jre for Windows
5095 bool os::is_headless_jre() { return false; }
5096
5097 static jint initSock() {
5098 WSADATA wsadata;
5099
5100 if (WSAStartup(MAKEWORD(2,2), &wsadata) != 0) {
5101 jio_fprintf(stderr, "Could not initialize Winsock (error: %d)\n",
5102 ::GetLastError());
5103 return JNI_ERR;
5104 }
5105 return JNI_OK;
5106 }
5107
5108 struct hostent* os::get_host_by_name(char* name) {
5109 return (struct hostent*)gethostbyname(name);
5110 }
5111
5112 int os::socket_close(int fd) {
5113 return ::closesocket(fd);
5114 }
5115
5116 int os::socket(int domain, int type, int protocol) {
5117 return ::socket(domain, type, protocol);
5118 }
5119
5120 int os::connect(int fd, struct sockaddr* him, socklen_t len) {
5121 return ::connect(fd, him, len);
5122 }
5123
5124 int os::recv(int fd, char* buf, size_t nBytes, uint flags) {
5125 return ::recv(fd, buf, (int)nBytes, flags);
5126 }
5127
5128 int os::send(int fd, char* buf, size_t nBytes, uint flags) {
5129 return ::send(fd, buf, (int)nBytes, flags);
5130 }
5131
5132 int os::raw_send(int fd, char* buf, size_t nBytes, uint flags) {
5133 return ::send(fd, buf, (int)nBytes, flags);
5134 }
5135
5136 // WINDOWS CONTEXT Flags for THREAD_SAMPLING
5137 #if defined(IA32)
5138 #define sampling_context_flags (CONTEXT_FULL | CONTEXT_FLOATING_POINT | CONTEXT_EXTENDED_REGISTERS)
5139 #elif defined (AMD64)
5140 #define sampling_context_flags (CONTEXT_FULL | CONTEXT_FLOATING_POINT)
5141 #endif
5142
5143 // returns true if thread could be suspended,
5144 // false otherwise
5145 static bool do_suspend(HANDLE* h) {
5146 if (h != NULL) {
5147 if (SuspendThread(*h) != ~0) {
5148 return true;
5149 }
5150 }
5151 return false;
5152 }
5153
5154 // resume the thread
5155 // calling resume on an active thread is a no-op
5156 static void do_resume(HANDLE* h) {
5157 if (h != NULL) {
5158 ResumeThread(*h);
5159 }
5160 }
5161
5162 // retrieve a suspend/resume context capable handle
5163 // from the tid. Caller validates handle return value.
5164 void get_thread_handle_for_extended_context(HANDLE* h,
5165 OSThread::thread_id_t tid) {
5166 if (h != NULL) {
5167 *h = OpenThread(THREAD_SUSPEND_RESUME | THREAD_GET_CONTEXT | THREAD_QUERY_INFORMATION, FALSE, tid);
5168 }
5169 }
5170
5171 // Thread sampling implementation
5172 //
5173 void os::SuspendedThreadTask::internal_do_task() {
5174 CONTEXT ctxt;
5175 HANDLE h = NULL;
5176
5177 // get context capable handle for thread
5178 get_thread_handle_for_extended_context(&h, _thread->osthread()->thread_id());
5179
5180 // sanity
5181 if (h == NULL || h == INVALID_HANDLE_VALUE) {
5182 return;
5183 }
5184
5185 // suspend the thread
5186 if (do_suspend(&h)) {
5187 ctxt.ContextFlags = sampling_context_flags;
5188 // get thread context
5189 GetThreadContext(h, &ctxt);
5190 SuspendedThreadTaskContext context(_thread, &ctxt);
5191 // pass context to Thread Sampling impl
5192 do_task(context);
5193 // resume thread
5194 do_resume(&h);
5195 }
5196
5197 // close handle
5198 CloseHandle(h);
5199 }
5200
5201 bool os::start_debugging(char *buf, int buflen) {
5202 int len = (int)strlen(buf);
5203 char *p = &buf[len];
5204
5205 jio_snprintf(p, buflen-len,
5206 "\n\n"
5207 "Do you want to debug the problem?\n\n"
5208 "To debug, attach Visual Studio to process %d; then switch to thread 0x%x\n"
5209 "Select 'Yes' to launch Visual Studio automatically (PATH must include msdev)\n"
5210 "Otherwise, select 'No' to abort...",
5211 os::current_process_id(), os::current_thread_id());
5212
5213 bool yes = os::message_box("Unexpected Error", buf);
5214
5215 if (yes) {
5216 // os::breakpoint() calls DebugBreak(), which causes a breakpoint
5217 // exception. If VM is running inside a debugger, the debugger will
5218 // catch the exception. Otherwise, the breakpoint exception will reach
5219 // the default windows exception handler, which can spawn a debugger and
5220 // automatically attach to the dying VM.
5221 os::breakpoint();
5222 yes = false;
5223 }
5224 return yes;
5225 }
5226
5227 void* os::get_default_process_handle() {
5228 return (void*)GetModuleHandle(NULL);
5229 }
5230
5231 // Builds a platform dependent Agent_OnLoad_<lib_name> function name
5232 // which is used to find statically linked in agents.
5233 // Additionally for windows, takes into account __stdcall names.
5234 // Parameters:
5235 // sym_name: Symbol in library we are looking for
5236 // lib_name: Name of library to look in, NULL for shared libs.
5237 // is_absolute_path == true if lib_name is absolute path to agent
5238 // such as "C:/a/b/L.dll"
5239 // == false if only the base name of the library is passed in
5240 // such as "L"
5241 char* os::build_agent_function_name(const char *sym_name, const char *lib_name,
5242 bool is_absolute_path) {
5243 char *agent_entry_name;
5244 size_t len;
5245 size_t name_len;
5246 size_t prefix_len = strlen(JNI_LIB_PREFIX);
5247 size_t suffix_len = strlen(JNI_LIB_SUFFIX);
5248 const char *start;
5249
5250 if (lib_name != NULL) {
5251 len = name_len = strlen(lib_name);
5252 if (is_absolute_path) {
5253 // Need to strip path, prefix and suffix
5254 if ((start = strrchr(lib_name, *os::file_separator())) != NULL) {
5255 lib_name = ++start;
5256 } else {
5257 // Need to check for drive prefix
5258 if ((start = strchr(lib_name, ':')) != NULL) {
5259 lib_name = ++start;
5260 }
5261 }
5262 if (len <= (prefix_len + suffix_len)) {
5263 return NULL;
5264 }
5265 lib_name += prefix_len;
5266 name_len = strlen(lib_name) - suffix_len;
5267 }
5268 }
5269 len = (lib_name != NULL ? name_len : 0) + strlen(sym_name) + 2;
5270 agent_entry_name = NEW_C_HEAP_ARRAY_RETURN_NULL(char, len, mtThread);
5271 if (agent_entry_name == NULL) {
5272 return NULL;
5273 }
5274 if (lib_name != NULL) {
5275 const char *p = strrchr(sym_name, '@');
5276 if (p != NULL && p != sym_name) {
5277 // sym_name == _Agent_OnLoad@XX
5278 strncpy(agent_entry_name, sym_name, (p - sym_name));
5279 agent_entry_name[(p-sym_name)] = '\0';
5280 // agent_entry_name == _Agent_OnLoad
5281 strcat(agent_entry_name, "_");
5282 strncat(agent_entry_name, lib_name, name_len);
5283 strcat(agent_entry_name, p);
5284 // agent_entry_name == _Agent_OnLoad_lib_name@XX
5285 } else {
5286 strcpy(agent_entry_name, sym_name);
5287 strcat(agent_entry_name, "_");
5288 strncat(agent_entry_name, lib_name, name_len);
5289 }
5290 } else {
5291 strcpy(agent_entry_name, sym_name);
5292 }
5293 return agent_entry_name;
5294 }
5295
5296 #ifndef PRODUCT
5297
5298 // test the code path in reserve_memory_special() that tries to allocate memory in a single
5299 // contiguous memory block at a particular address.
5300 // The test first tries to find a good approximate address to allocate at by using the same
5301 // method to allocate some memory at any address. The test then tries to allocate memory in
5302 // the vicinity (not directly after it to avoid possible by-chance use of that location)
5303 // This is of course only some dodgy assumption, there is no guarantee that the vicinity of
5304 // the previously allocated memory is available for allocation. The only actual failure
5305 // that is reported is when the test tries to allocate at a particular location but gets a
5306 // different valid one. A NULL return value at this point is not considered an error but may
5307 // be legitimate.
5308 // If -XX:+VerboseInternalVMTests is enabled, print some explanatory messages.
5309 void TestReserveMemorySpecial_test() {
5310 if (!UseLargePages) {
5311 if (VerboseInternalVMTests) {
5312 tty->print("Skipping test because large pages are disabled");
5313 }
5314 return;
5315 }
5316 // save current value of globals
5317 bool old_use_large_pages_individual_allocation = UseLargePagesIndividualAllocation;
5318 bool old_use_numa_interleaving = UseNUMAInterleaving;
5319
5320 // set globals to make sure we hit the correct code path
5321 UseLargePagesIndividualAllocation = UseNUMAInterleaving = false;
5322
5323 // do an allocation at an address selected by the OS to get a good one.
5324 const size_t large_allocation_size = os::large_page_size() * 4;
5325 char* result = os::reserve_memory_special(large_allocation_size, os::large_page_size(), NULL, false);
5326 if (result == NULL) {
5327 if (VerboseInternalVMTests) {
5328 tty->print("Failed to allocate control block with size " SIZE_FORMAT ". Skipping remainder of test.",
5329 large_allocation_size);
5330 }
5331 } else {
5332 os::release_memory_special(result, large_allocation_size);
5333
5334 // allocate another page within the recently allocated memory area which seems to be a good location. At least
5335 // we managed to get it once.
5336 const size_t expected_allocation_size = os::large_page_size();
5337 char* expected_location = result + os::large_page_size();
5338 char* actual_location = os::reserve_memory_special(expected_allocation_size, os::large_page_size(), expected_location, false);
5339 if (actual_location == NULL) {
5340 if (VerboseInternalVMTests) {
5341 tty->print("Failed to allocate any memory at " PTR_FORMAT " size " SIZE_FORMAT ". Skipping remainder of test.",
5342 expected_location, large_allocation_size);
5343 }
5344 } else {
5345 // release memory
5346 os::release_memory_special(actual_location, expected_allocation_size);
5347 // only now check, after releasing any memory to avoid any leaks.
5348 assert(actual_location == expected_location,
5349 "Failed to allocate memory at requested location " PTR_FORMAT " of size " SIZE_FORMAT ", is " PTR_FORMAT " instead",
5350 expected_location, expected_allocation_size, actual_location);
5351 }
5352 }
5353
5354 // restore globals
5355 UseLargePagesIndividualAllocation = old_use_large_pages_individual_allocation;
5356 UseNUMAInterleaving = old_use_numa_interleaving;
5357 }
5358 #endif // PRODUCT
5359
5360 /*
5361 All the defined signal names for Windows.
5362
5363 NOTE that not all of these names are accepted by FindSignal!
5364
5365 For various reasons some of these may be rejected at runtime.
5366
5367 Here are the names currently accepted by a user of sun.misc.Signal with
5368 1.4.1 (ignoring potential interaction with use of chaining, etc):
5369
5370 (LIST TBD)
5371
5372 */
5373 int os::get_signal_number(const char* name) {
5374 static const struct {
5375 char* name;
5376 int number;
5377 } siglabels [] =
5378 // derived from version 6.0 VC98/include/signal.h
5379 {"ABRT", SIGABRT, // abnormal termination triggered by abort cl
5380 "FPE", SIGFPE, // floating point exception
5381 "SEGV", SIGSEGV, // segment violation
5382 "INT", SIGINT, // interrupt
5383 "TERM", SIGTERM, // software term signal from kill
5384 "BREAK", SIGBREAK, // Ctrl-Break sequence
5385 "ILL", SIGILL}; // illegal instruction
5386 for (unsigned i = 0; i < ARRAY_SIZE(siglabels); ++i) {
5387 if (strcmp(name, siglabels[i].name) == 0) {
5388 return siglabels[i].number;
5389 }
5390 }
5391 return -1;
5392 }
5393
5394 // Fast current thread access
5395
5396 int os::win32::_thread_ptr_offset = 0;
5397
5398 static void call_wrapper_dummy() {}
5399
5400 // We need to call the os_exception_wrapper once so that it sets
5401 // up the offset from FS of the thread pointer.
5402 void os::win32::initialize_thread_ptr_offset() {
5403 os::os_exception_wrapper((java_call_t)call_wrapper_dummy,
5404 NULL, NULL, NULL, NULL);
5405 }