1 /*
2 * Copyright (c) 1999, 2020, 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 // no precompiled headers
26 #include "jvm.h"
27 #include "classfile/classLoader.hpp"
28 #include "classfile/systemDictionary.hpp"
29 #include "classfile/vmSymbols.hpp"
30 #include "code/icBuffer.hpp"
31 #include "code/vtableStubs.hpp"
32 #include "compiler/compileBroker.hpp"
33 #include "compiler/disassembler.hpp"
34 #include "interpreter/interpreter.hpp"
35 #include "logging/log.hpp"
36 #include "logging/logStream.hpp"
37 #include "memory/allocation.inline.hpp"
38 #include "memory/filemap.hpp"
39 #include "oops/oop.inline.hpp"
40 #include "os_bsd.inline.hpp"
41 #include "os_posix.inline.hpp"
42 #include "os_share_bsd.hpp"
43 #include "prims/jniFastGetField.hpp"
44 #include "prims/jvm_misc.hpp"
45 #include "runtime/arguments.hpp"
46 #include "runtime/atomic.hpp"
47 #include "runtime/globals.hpp"
48 #include "runtime/interfaceSupport.inline.hpp"
49 #include "runtime/java.hpp"
50 #include "runtime/javaCalls.hpp"
51 #include "runtime/mutexLocker.hpp"
52 #include "runtime/objectMonitor.hpp"
53 #include "runtime/osThread.hpp"
54 #include "runtime/perfMemory.hpp"
55 #include "runtime/semaphore.hpp"
56 #include "runtime/sharedRuntime.hpp"
57 #include "runtime/statSampler.hpp"
58 #include "runtime/stubRoutines.hpp"
59 #include "runtime/thread.inline.hpp"
60 #include "runtime/threadCritical.hpp"
61 #include "runtime/timer.hpp"
62 #include "services/attachListener.hpp"
63 #include "services/memTracker.hpp"
64 #include "services/runtimeService.hpp"
65 #include "utilities/align.hpp"
66 #include "utilities/decoder.hpp"
67 #include "utilities/defaultStream.hpp"
68 #include "utilities/events.hpp"
69 #include "utilities/growableArray.hpp"
70 #include "utilities/vmError.hpp"
71
72 // put OS-includes here
73 # include <dlfcn.h>
74 # include <errno.h>
75 # include <fcntl.h>
76 # include <inttypes.h>
77 # include <poll.h>
78 # include <pthread.h>
79 # include <pwd.h>
80 # include <signal.h>
81 # include <stdint.h>
82 # include <stdio.h>
83 # include <string.h>
84 # include <sys/ioctl.h>
85 # include <sys/mman.h>
86 # include <sys/param.h>
87 # include <sys/resource.h>
88 # include <sys/socket.h>
89 # include <sys/stat.h>
90 # include <sys/syscall.h>
91 # include <sys/sysctl.h>
92 # include <sys/time.h>
93 # include <sys/times.h>
94 # include <sys/types.h>
95 # include <sys/wait.h>
96 # include <time.h>
97 # include <unistd.h>
98
99 #if defined(__FreeBSD__) || defined(__NetBSD__)
100 #include <elf.h>
101 #endif
102
103 #ifdef __APPLE__
104 #include <mach-o/dyld.h>
105 #endif
106
107 #ifndef MAP_ANONYMOUS
108 #define MAP_ANONYMOUS MAP_ANON
109 #endif
110
111 #define MAX_PATH (2 * K)
112
113 // for timer info max values which include all bits
114 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF)
115
116 ////////////////////////////////////////////////////////////////////////////////
117 // global variables
118 julong os::Bsd::_physical_memory = 0;
119
120 #ifdef __APPLE__
121 mach_timebase_info_data_t os::Bsd::_timebase_info = {0, 0};
122 volatile uint64_t os::Bsd::_max_abstime = 0;
123 #else
124 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL;
125 #endif
126 pthread_t os::Bsd::_main_thread;
127 int os::Bsd::_page_size = -1;
128
129 static jlong initial_time_count=0;
130
131 static int clock_tics_per_sec = 100;
132
133 // For diagnostics to print a message once. see run_periodic_checks
134 static sigset_t check_signal_done;
135 static bool check_signals = true;
136
137 // Signal number used to suspend/resume a thread
138
139 // do not use any signal number less than SIGSEGV, see 4355769
140 static int SR_signum = SIGUSR2;
141 sigset_t SR_sigset;
142
143 #ifdef __APPLE__
144 static const int processor_id_unassigned = -1;
145 static const int processor_id_assigning = -2;
146 static const int processor_id_map_size = 256;
147 static volatile int processor_id_map[processor_id_map_size];
148 static volatile int processor_id_next = 0;
149 #endif
150
151 ////////////////////////////////////////////////////////////////////////////////
152 // utility functions
153
154 static int SR_initialize();
155
156 julong os::available_memory() {
157 return Bsd::available_memory();
158 }
159
160 // available here means free
161 julong os::Bsd::available_memory() {
162 uint64_t available = physical_memory() >> 2;
163 #ifdef __APPLE__
164 mach_msg_type_number_t count = HOST_VM_INFO64_COUNT;
165 vm_statistics64_data_t vmstat;
166 kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64,
167 (host_info64_t)&vmstat, &count);
168 assert(kerr == KERN_SUCCESS,
169 "host_statistics64 failed - check mach_host_self() and count");
170 if (kerr == KERN_SUCCESS) {
171 available = vmstat.free_count * os::vm_page_size();
172 }
173 #endif
174 return available;
175 }
176
177 // for more info see :
178 // https://man.openbsd.org/sysctl.2
179 void os::Bsd::print_uptime_info(outputStream* st) {
180 struct timeval boottime;
181 size_t len = sizeof(boottime);
182 int mib[2];
183 mib[0] = CTL_KERN;
184 mib[1] = KERN_BOOTTIME;
185
186 if (sysctl(mib, 2, &boottime, &len, NULL, 0) >= 0) {
187 time_t bootsec = boottime.tv_sec;
188 time_t currsec = time(NULL);
189 os::print_dhm(st, "OS uptime:", (long) difftime(currsec, bootsec));
190 }
191 }
192
193 julong os::physical_memory() {
194 return Bsd::physical_memory();
195 }
196
197 // Return true if user is running as root.
198
199 bool os::have_special_privileges() {
200 static bool init = false;
201 static bool privileges = false;
202 if (!init) {
203 privileges = (getuid() != geteuid()) || (getgid() != getegid());
204 init = true;
205 }
206 return privileges;
207 }
208
209
210
211 // Cpu architecture string
212 #if defined(ZERO)
213 static char cpu_arch[] = ZERO_LIBARCH;
214 #elif defined(IA64)
215 static char cpu_arch[] = "ia64";
216 #elif defined(IA32)
217 static char cpu_arch[] = "i386";
218 #elif defined(AMD64)
219 static char cpu_arch[] = "amd64";
220 #elif defined(ARM)
221 static char cpu_arch[] = "arm";
222 #elif defined(PPC32)
223 static char cpu_arch[] = "ppc";
224 #else
225 #error Add appropriate cpu_arch setting
226 #endif
227
228 // Compiler variant
229 #ifdef COMPILER2
230 #define COMPILER_VARIANT "server"
231 #else
232 #define COMPILER_VARIANT "client"
233 #endif
234
235
236 void os::Bsd::initialize_system_info() {
237 int mib[2];
238 size_t len;
239 int cpu_val;
240 julong mem_val;
241
242 // get processors count via hw.ncpus sysctl
243 mib[0] = CTL_HW;
244 mib[1] = HW_NCPU;
245 len = sizeof(cpu_val);
246 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) {
247 assert(len == sizeof(cpu_val), "unexpected data size");
248 set_processor_count(cpu_val);
249 } else {
250 set_processor_count(1); // fallback
251 }
252
253 #ifdef __APPLE__
254 // initialize processor id map
255 for (int i = 0; i < processor_id_map_size; i++) {
256 processor_id_map[i] = processor_id_unassigned;
257 }
258 #endif
259
260 // get physical memory via hw.memsize sysctl (hw.memsize is used
261 // since it returns a 64 bit value)
262 mib[0] = CTL_HW;
263
264 #if defined (HW_MEMSIZE) // Apple
265 mib[1] = HW_MEMSIZE;
266 #elif defined(HW_PHYSMEM) // Most of BSD
267 mib[1] = HW_PHYSMEM;
268 #elif defined(HW_REALMEM) // Old FreeBSD
269 mib[1] = HW_REALMEM;
270 #else
271 #error No ways to get physmem
272 #endif
273
274 len = sizeof(mem_val);
275 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) {
276 assert(len == sizeof(mem_val), "unexpected data size");
277 _physical_memory = mem_val;
278 } else {
279 _physical_memory = 256 * 1024 * 1024; // fallback (XXXBSD?)
280 }
281
282 #ifdef __OpenBSD__
283 {
284 // limit _physical_memory memory view on OpenBSD since
285 // datasize rlimit restricts us anyway.
286 struct rlimit limits;
287 getrlimit(RLIMIT_DATA, &limits);
288 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur);
289 }
290 #endif
291 }
292
293 #ifdef __APPLE__
294 static const char *get_home() {
295 const char *home_dir = ::getenv("HOME");
296 if ((home_dir == NULL) || (*home_dir == '\0')) {
297 struct passwd *passwd_info = getpwuid(geteuid());
298 if (passwd_info != NULL) {
299 home_dir = passwd_info->pw_dir;
300 }
301 }
302
303 return home_dir;
304 }
305 #endif
306
307 void os::init_system_properties_values() {
308 // The next steps are taken in the product version:
309 //
310 // Obtain the JAVA_HOME value from the location of libjvm.so.
311 // This library should be located at:
312 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so.
313 //
314 // If "/jre/lib/" appears at the right place in the path, then we
315 // assume libjvm.so is installed in a JDK and we use this path.
316 //
317 // Otherwise exit with message: "Could not create the Java virtual machine."
318 //
319 // The following extra steps are taken in the debugging version:
320 //
321 // If "/jre/lib/" does NOT appear at the right place in the path
322 // instead of exit check for $JAVA_HOME environment variable.
323 //
324 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>,
325 // then we append a fake suffix "hotspot/libjvm.so" to this path so
326 // it looks like libjvm.so is installed there
327 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so.
328 //
329 // Otherwise exit.
330 //
331 // Important note: if the location of libjvm.so changes this
332 // code needs to be changed accordingly.
333
334 // See ld(1):
335 // The linker uses the following search paths to locate required
336 // shared libraries:
337 // 1: ...
338 // ...
339 // 7: The default directories, normally /lib and /usr/lib.
340 #ifndef DEFAULT_LIBPATH
341 #ifndef OVERRIDE_LIBPATH
342 #define DEFAULT_LIBPATH "/lib:/usr/lib"
343 #else
344 #define DEFAULT_LIBPATH OVERRIDE_LIBPATH
345 #endif
346 #endif
347
348 // Base path of extensions installed on the system.
349 #define SYS_EXT_DIR "/usr/java/packages"
350 #define EXTENSIONS_DIR "/lib/ext"
351
352 #ifndef __APPLE__
353
354 // Buffer that fits several sprintfs.
355 // Note that the space for the colon and the trailing null are provided
356 // by the nulls included by the sizeof operator.
357 const size_t bufsize =
358 MAX2((size_t)MAXPATHLEN, // For dll_dir & friends.
359 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + sizeof(SYS_EXT_DIR) + sizeof(EXTENSIONS_DIR)); // extensions dir
360 char *buf = NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
361
362 // sysclasspath, java_home, dll_dir
363 {
364 char *pslash;
365 os::jvm_path(buf, bufsize);
366
367 // Found the full path to libjvm.so.
368 // Now cut the path to <java_home>/jre if we can.
369 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
370 pslash = strrchr(buf, '/');
371 if (pslash != NULL) {
372 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
373 }
374 Arguments::set_dll_dir(buf);
375
376 if (pslash != NULL) {
377 pslash = strrchr(buf, '/');
378 if (pslash != NULL) {
379 *pslash = '\0'; // Get rid of /<arch>.
380 pslash = strrchr(buf, '/');
381 if (pslash != NULL) {
382 *pslash = '\0'; // Get rid of /lib.
383 }
384 }
385 }
386 Arguments::set_java_home(buf);
387 if (!set_boot_path('/', ':')) {
388 vm_exit_during_initialization("Failed setting boot class path.", NULL);
389 }
390 }
391
392 // Where to look for native libraries.
393 //
394 // Note: Due to a legacy implementation, most of the library path
395 // is set in the launcher. This was to accomodate linking restrictions
396 // on legacy Bsd implementations (which are no longer supported).
397 // Eventually, all the library path setting will be done here.
398 //
399 // However, to prevent the proliferation of improperly built native
400 // libraries, the new path component /usr/java/packages is added here.
401 // Eventually, all the library path setting will be done here.
402 {
403 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
404 // should always exist (until the legacy problem cited above is
405 // addressed).
406 const char *v = ::getenv("LD_LIBRARY_PATH");
407 const char *v_colon = ":";
408 if (v == NULL) { v = ""; v_colon = ""; }
409 // That's +1 for the colon and +1 for the trailing '\0'.
410 char *ld_library_path = NEW_C_HEAP_ARRAY(char,
411 strlen(v) + 1 +
412 sizeof(SYS_EXT_DIR) + sizeof("/lib/") + strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH) + 1,
413 mtInternal);
414 sprintf(ld_library_path, "%s%s" SYS_EXT_DIR "/lib/%s:" DEFAULT_LIBPATH, v, v_colon, cpu_arch);
415 Arguments::set_library_path(ld_library_path);
416 FREE_C_HEAP_ARRAY(char, ld_library_path);
417 }
418
419 // Extensions directories.
420 sprintf(buf, "%s" EXTENSIONS_DIR ":" SYS_EXT_DIR EXTENSIONS_DIR, Arguments::get_java_home());
421 Arguments::set_ext_dirs(buf);
422
423 FREE_C_HEAP_ARRAY(char, buf);
424
425 #else // __APPLE__
426
427 #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions"
428 #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java"
429
430 const char *user_home_dir = get_home();
431 // The null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir.
432 size_t system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) +
433 sizeof(SYS_EXTENSIONS_DIRS);
434
435 // Buffer that fits several sprintfs.
436 // Note that the space for the colon and the trailing null are provided
437 // by the nulls included by the sizeof operator.
438 const size_t bufsize =
439 MAX2((size_t)MAXPATHLEN, // for dll_dir & friends.
440 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + system_ext_size); // extensions dir
441 char *buf = NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
442
443 // sysclasspath, java_home, dll_dir
444 {
445 char *pslash;
446 os::jvm_path(buf, bufsize);
447
448 // Found the full path to libjvm.so.
449 // Now cut the path to <java_home>/jre if we can.
450 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
451 pslash = strrchr(buf, '/');
452 if (pslash != NULL) {
453 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
454 }
455 #ifdef STATIC_BUILD
456 strcat(buf, "/lib");
457 #endif
458
459 Arguments::set_dll_dir(buf);
460
461 if (pslash != NULL) {
462 pslash = strrchr(buf, '/');
463 if (pslash != NULL) {
464 *pslash = '\0'; // Get rid of /lib.
465 }
466 }
467 Arguments::set_java_home(buf);
468 set_boot_path('/', ':');
469 }
470
471 // Where to look for native libraries.
472 //
473 // Note: Due to a legacy implementation, most of the library path
474 // is set in the launcher. This was to accomodate linking restrictions
475 // on legacy Bsd implementations (which are no longer supported).
476 // Eventually, all the library path setting will be done here.
477 //
478 // However, to prevent the proliferation of improperly built native
479 // libraries, the new path component /usr/java/packages is added here.
480 // Eventually, all the library path setting will be done here.
481 {
482 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
483 // should always exist (until the legacy problem cited above is
484 // addressed).
485 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code
486 // can specify a directory inside an app wrapper
487 const char *l = ::getenv("JAVA_LIBRARY_PATH");
488 const char *l_colon = ":";
489 if (l == NULL) { l = ""; l_colon = ""; }
490
491 const char *v = ::getenv("DYLD_LIBRARY_PATH");
492 const char *v_colon = ":";
493 if (v == NULL) { v = ""; v_colon = ""; }
494
495 // Apple's Java6 has "." at the beginning of java.library.path.
496 // OpenJDK on Windows has "." at the end of java.library.path.
497 // OpenJDK on Linux and Solaris don't have "." in java.library.path
498 // at all. To ease the transition from Apple's Java6 to OpenJDK7,
499 // "." is appended to the end of java.library.path. Yes, this
500 // could cause a change in behavior, but Apple's Java6 behavior
501 // can be achieved by putting "." at the beginning of the
502 // JAVA_LIBRARY_PATH environment variable.
503 char *ld_library_path = NEW_C_HEAP_ARRAY(char,
504 strlen(v) + 1 + strlen(l) + 1 +
505 system_ext_size + 3,
506 mtInternal);
507 sprintf(ld_library_path, "%s%s%s%s%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS ":.",
508 v, v_colon, l, l_colon, user_home_dir);
509 Arguments::set_library_path(ld_library_path);
510 FREE_C_HEAP_ARRAY(char, ld_library_path);
511 }
512
513 // Extensions directories.
514 //
515 // Note that the space for the colon and the trailing null are provided
516 // by the nulls included by the sizeof operator (so actually one byte more
517 // than necessary is allocated).
518 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS,
519 user_home_dir, Arguments::get_java_home());
520 Arguments::set_ext_dirs(buf);
521
522 FREE_C_HEAP_ARRAY(char, buf);
523
524 #undef SYS_EXTENSIONS_DIR
525 #undef SYS_EXTENSIONS_DIRS
526
527 #endif // __APPLE__
528
529 #undef SYS_EXT_DIR
530 #undef EXTENSIONS_DIR
531 }
532
533 ////////////////////////////////////////////////////////////////////////////////
534 // breakpoint support
535
536 void os::breakpoint() {
537 BREAKPOINT;
538 }
539
540 extern "C" void breakpoint() {
541 // use debugger to set breakpoint here
542 }
543
544 ////////////////////////////////////////////////////////////////////////////////
545 // signal support
546
547 debug_only(static bool signal_sets_initialized = false);
548 static sigset_t unblocked_sigs, vm_sigs;
549
550 void os::Bsd::signal_sets_init() {
551 // Should also have an assertion stating we are still single-threaded.
552 assert(!signal_sets_initialized, "Already initialized");
553 // Fill in signals that are necessarily unblocked for all threads in
554 // the VM. Currently, we unblock the following signals:
555 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
556 // by -Xrs (=ReduceSignalUsage));
557 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
558 // other threads. The "ReduceSignalUsage" boolean tells us not to alter
559 // the dispositions or masks wrt these signals.
560 // Programs embedding the VM that want to use the above signals for their
561 // own purposes must, at this time, use the "-Xrs" option to prevent
562 // interference with shutdown hooks and BREAK_SIGNAL thread dumping.
563 // (See bug 4345157, and other related bugs).
564 // In reality, though, unblocking these signals is really a nop, since
565 // these signals are not blocked by default.
566 sigemptyset(&unblocked_sigs);
567 sigaddset(&unblocked_sigs, SIGILL);
568 sigaddset(&unblocked_sigs, SIGSEGV);
569 sigaddset(&unblocked_sigs, SIGBUS);
570 sigaddset(&unblocked_sigs, SIGFPE);
571 sigaddset(&unblocked_sigs, SR_signum);
572
573 if (!ReduceSignalUsage) {
574 if (!os::Posix::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
575 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
576
577 }
578 if (!os::Posix::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
579 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
580 }
581 if (!os::Posix::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
582 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
583 }
584 }
585 // Fill in signals that are blocked by all but the VM thread.
586 sigemptyset(&vm_sigs);
587 if (!ReduceSignalUsage) {
588 sigaddset(&vm_sigs, BREAK_SIGNAL);
589 }
590 debug_only(signal_sets_initialized = true);
591
592 }
593
594 // These are signals that are unblocked while a thread is running Java.
595 // (For some reason, they get blocked by default.)
596 sigset_t* os::Bsd::unblocked_signals() {
597 assert(signal_sets_initialized, "Not initialized");
598 return &unblocked_sigs;
599 }
600
601 // These are the signals that are blocked while a (non-VM) thread is
602 // running Java. Only the VM thread handles these signals.
603 sigset_t* os::Bsd::vm_signals() {
604 assert(signal_sets_initialized, "Not initialized");
605 return &vm_sigs;
606 }
607
608 void os::Bsd::hotspot_sigmask(Thread* thread) {
609
610 //Save caller's signal mask before setting VM signal mask
611 sigset_t caller_sigmask;
612 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
613
614 OSThread* osthread = thread->osthread();
615 osthread->set_caller_sigmask(caller_sigmask);
616
617 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL);
618
619 if (!ReduceSignalUsage) {
620 if (thread->is_VM_thread()) {
621 // Only the VM thread handles BREAK_SIGNAL ...
622 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
623 } else {
624 // ... all other threads block BREAK_SIGNAL
625 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
626 }
627 }
628 }
629
630
631 //////////////////////////////////////////////////////////////////////////////
632 // create new thread
633
634 #ifdef __APPLE__
635 // library handle for calling objc_registerThreadWithCollector()
636 // without static linking to the libobjc library
637 #define OBJC_LIB "/usr/lib/libobjc.dylib"
638 #define OBJC_GCREGISTER "objc_registerThreadWithCollector"
639 typedef void (*objc_registerThreadWithCollector_t)();
640 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction;
641 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL;
642 #endif
643
644 // Thread start routine for all newly created threads
645 static void *thread_native_entry(Thread *thread) {
646
647 thread->record_stack_base_and_size();
648
649 // Try to randomize the cache line index of hot stack frames.
650 // This helps when threads of the same stack traces evict each other's
651 // cache lines. The threads can be either from the same JVM instance, or
652 // from different JVM instances. The benefit is especially true for
653 // processors with hyperthreading technology.
654 static int counter = 0;
655 int pid = os::current_process_id();
656 alloca(((pid ^ counter++) & 7) * 128);
657
658 thread->initialize_thread_current();
659
660 OSThread* osthread = thread->osthread();
661 Monitor* sync = osthread->startThread_lock();
662
663 osthread->set_thread_id(os::Bsd::gettid());
664
665 log_info(os, thread)("Thread is alive (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").",
666 os::current_thread_id(), (uintx) pthread_self());
667
668 #ifdef __APPLE__
669 // Store unique OS X thread id used by SA
670 osthread->set_unique_thread_id();
671 #endif
672
673 // initialize signal mask for this thread
674 os::Bsd::hotspot_sigmask(thread);
675
676 // initialize floating point control register
677 os::Bsd::init_thread_fpu_state();
678
679 #ifdef __APPLE__
680 // register thread with objc gc
681 if (objc_registerThreadWithCollectorFunction != NULL) {
682 objc_registerThreadWithCollectorFunction();
683 }
684 #endif
685
686 // handshaking with parent thread
687 {
688 MutexLocker ml(sync, Mutex::_no_safepoint_check_flag);
689
690 // notify parent thread
691 osthread->set_state(INITIALIZED);
692 sync->notify_all();
693
694 // wait until os::start_thread()
695 while (osthread->get_state() == INITIALIZED) {
696 sync->wait_without_safepoint_check();
697 }
698 }
699
700 // call one more level start routine
701 thread->call_run();
702
703 // Note: at this point the thread object may already have deleted itself.
704 // Prevent dereferencing it from here on out.
705 thread = NULL;
706
707 log_info(os, thread)("Thread finished (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").",
708 os::current_thread_id(), (uintx) pthread_self());
709
710 return 0;
711 }
712
713 bool os::create_thread(Thread* thread, ThreadType thr_type,
714 size_t req_stack_size) {
715 assert(thread->osthread() == NULL, "caller responsible");
716
717 // Allocate the OSThread object
718 OSThread* osthread = new OSThread(NULL, NULL);
719 if (osthread == NULL) {
720 return false;
721 }
722
723 // set the correct thread state
724 osthread->set_thread_type(thr_type);
725
726 // Initial state is ALLOCATED but not INITIALIZED
727 osthread->set_state(ALLOCATED);
728
729 thread->set_osthread(osthread);
730
731 // init thread attributes
732 pthread_attr_t attr;
733 pthread_attr_init(&attr);
734 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
735
736 // calculate stack size if it's not specified by caller
737 size_t stack_size = os::Posix::get_initial_stack_size(thr_type, req_stack_size);
738 int status = pthread_attr_setstacksize(&attr, stack_size);
739 assert_status(status == 0, status, "pthread_attr_setstacksize");
740
741 ThreadState state;
742
743 {
744 pthread_t tid;
745 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) thread_native_entry, thread);
746
747 char buf[64];
748 if (ret == 0) {
749 log_info(os, thread)("Thread started (pthread id: " UINTX_FORMAT ", attributes: %s). ",
750 (uintx) tid, os::Posix::describe_pthread_attr(buf, sizeof(buf), &attr));
751 } else {
752 log_warning(os, thread)("Failed to start thread - pthread_create failed (%s) for attributes: %s.",
753 os::errno_name(ret), os::Posix::describe_pthread_attr(buf, sizeof(buf), &attr));
754 // Log some OS information which might explain why creating the thread failed.
755 log_info(os, thread)("Number of threads approx. running in the VM: %d", Threads::number_of_threads());
756 LogStream st(Log(os, thread)::info());
757 os::Posix::print_rlimit_info(&st);
758 os::print_memory_info(&st);
759 }
760
761 pthread_attr_destroy(&attr);
762
763 if (ret != 0) {
764 // Need to clean up stuff we've allocated so far
765 thread->set_osthread(NULL);
766 delete osthread;
767 return false;
768 }
769
770 // Store pthread info into the OSThread
771 osthread->set_pthread_id(tid);
772
773 // Wait until child thread is either initialized or aborted
774 {
775 Monitor* sync_with_child = osthread->startThread_lock();
776 MutexLocker ml(sync_with_child, Mutex::_no_safepoint_check_flag);
777 while ((state = osthread->get_state()) == ALLOCATED) {
778 sync_with_child->wait_without_safepoint_check();
779 }
780 }
781
782 }
783
784 // Aborted due to thread limit being reached
785 if (state == ZOMBIE) {
786 thread->set_osthread(NULL);
787 delete osthread;
788 return false;
789 }
790
791 // The thread is returned suspended (in state INITIALIZED),
792 // and is started higher up in the call chain
793 assert(state == INITIALIZED, "race condition");
794 return true;
795 }
796
797 /////////////////////////////////////////////////////////////////////////////
798 // attach existing thread
799
800 // bootstrap the main thread
801 bool os::create_main_thread(JavaThread* thread) {
802 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
803 return create_attached_thread(thread);
804 }
805
806 bool os::create_attached_thread(JavaThread* thread) {
807 #ifdef ASSERT
808 thread->verify_not_published();
809 #endif
810
811 // Allocate the OSThread object
812 OSThread* osthread = new OSThread(NULL, NULL);
813
814 if (osthread == NULL) {
815 return false;
816 }
817
818 osthread->set_thread_id(os::Bsd::gettid());
819
820 #ifdef __APPLE__
821 // Store unique OS X thread id used by SA
822 osthread->set_unique_thread_id();
823 #endif
824
825 // Store pthread info into the OSThread
826 osthread->set_pthread_id(::pthread_self());
827
828 // initialize floating point control register
829 os::Bsd::init_thread_fpu_state();
830
831 // Initial thread state is RUNNABLE
832 osthread->set_state(RUNNABLE);
833
834 thread->set_osthread(osthread);
835
836 // initialize signal mask for this thread
837 // and save the caller's signal mask
838 os::Bsd::hotspot_sigmask(thread);
839
840 log_info(os, thread)("Thread attached (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").",
841 os::current_thread_id(), (uintx) pthread_self());
842
843 return true;
844 }
845
846 void os::pd_start_thread(Thread* thread) {
847 OSThread * osthread = thread->osthread();
848 assert(osthread->get_state() != INITIALIZED, "just checking");
849 Monitor* sync_with_child = osthread->startThread_lock();
850 MutexLocker ml(sync_with_child, Mutex::_no_safepoint_check_flag);
851 sync_with_child->notify();
852 }
853
854 // Free Bsd resources related to the OSThread
855 void os::free_thread(OSThread* osthread) {
856 assert(osthread != NULL, "osthread not set");
857
858 // We are told to free resources of the argument thread,
859 // but we can only really operate on the current thread.
860 assert(Thread::current()->osthread() == osthread,
861 "os::free_thread but not current thread");
862
863 // Restore caller's signal mask
864 sigset_t sigmask = osthread->caller_sigmask();
865 pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
866
867 delete osthread;
868 }
869
870 ////////////////////////////////////////////////////////////////////////////////
871 // time support
872
873 // Time since start-up in seconds to a fine granularity.
874 // Used by VMSelfDestructTimer and the MemProfiler.
875 double os::elapsedTime() {
876
877 return ((double)os::elapsed_counter()) / os::elapsed_frequency();
878 }
879
880 jlong os::elapsed_counter() {
881 return javaTimeNanos() - initial_time_count;
882 }
883
884 jlong os::elapsed_frequency() {
885 return NANOSECS_PER_SEC; // nanosecond resolution
886 }
887
888 bool os::supports_vtime() { return true; }
889
890 double os::elapsedVTime() {
891 // better than nothing, but not much
892 return elapsedTime();
893 }
894
895 jlong os::javaTimeMillis() {
896 timeval time;
897 int status = gettimeofday(&time, NULL);
898 assert(status != -1, "bsd error");
899 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
900 }
901
902 void os::javaTimeSystemUTC(jlong &seconds, jlong &nanos) {
903 timeval time;
904 int status = gettimeofday(&time, NULL);
905 assert(status != -1, "bsd error");
906 seconds = jlong(time.tv_sec);
907 nanos = jlong(time.tv_usec) * 1000;
908 }
909
910 #ifndef __APPLE__
911 #ifndef CLOCK_MONOTONIC
912 #define CLOCK_MONOTONIC (1)
913 #endif
914 #endif
915
916 #ifdef __APPLE__
917 void os::Bsd::clock_init() {
918 mach_timebase_info(&_timebase_info);
919 }
920 #else
921 void os::Bsd::clock_init() {
922 struct timespec res;
923 struct timespec tp;
924 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
925 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) {
926 // yes, monotonic clock is supported
927 _clock_gettime = ::clock_gettime;
928 }
929 }
930 #endif
931
932
933
934 #ifdef __APPLE__
935
936 jlong os::javaTimeNanos() {
937 const uint64_t tm = mach_absolute_time();
938 const uint64_t now = (tm * Bsd::_timebase_info.numer) / Bsd::_timebase_info.denom;
939 const uint64_t prev = Bsd::_max_abstime;
940 if (now <= prev) {
941 return prev; // same or retrograde time;
942 }
943 const uint64_t obsv = Atomic::cmpxchg(&Bsd::_max_abstime, prev, now);
944 assert(obsv >= prev, "invariant"); // Monotonicity
945 // If the CAS succeeded then we're done and return "now".
946 // If the CAS failed and the observed value "obsv" is >= now then
947 // we should return "obsv". If the CAS failed and now > obsv > prv then
948 // some other thread raced this thread and installed a new value, in which case
949 // we could either (a) retry the entire operation, (b) retry trying to install now
950 // or (c) just return obsv. We use (c). No loop is required although in some cases
951 // we might discard a higher "now" value in deference to a slightly lower but freshly
952 // installed obsv value. That's entirely benign -- it admits no new orderings compared
953 // to (a) or (b) -- and greatly reduces coherence traffic.
954 // We might also condition (c) on the magnitude of the delta between obsv and now.
955 // Avoiding excessive CAS operations to hot RW locations is critical.
956 // See https://blogs.oracle.com/dave/entry/cas_and_cache_trivia_invalidate
957 return (prev == obsv) ? now : obsv;
958 }
959
960 #else // __APPLE__
961
962 jlong os::javaTimeNanos() {
963 if (os::supports_monotonic_clock()) {
964 struct timespec tp;
965 int status = Bsd::_clock_gettime(CLOCK_MONOTONIC, &tp);
966 assert(status == 0, "gettime error");
967 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
968 return result;
969 } else {
970 timeval time;
971 int status = gettimeofday(&time, NULL);
972 assert(status != -1, "bsd error");
973 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
974 return 1000 * usecs;
975 }
976 }
977
978 #endif // __APPLE__
979
980 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
981 if (os::supports_monotonic_clock()) {
982 info_ptr->max_value = ALL_64_BITS;
983
984 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
985 info_ptr->may_skip_backward = false; // not subject to resetting or drifting
986 info_ptr->may_skip_forward = false; // not subject to resetting or drifting
987 } else {
988 // gettimeofday - based on time in seconds since the Epoch thus does not wrap
989 info_ptr->max_value = ALL_64_BITS;
990
991 // gettimeofday is a real time clock so it skips
992 info_ptr->may_skip_backward = true;
993 info_ptr->may_skip_forward = true;
994 }
995
996 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
997 }
998
999 // Return the real, user, and system times in seconds from an
1000 // arbitrary fixed point in the past.
1001 bool os::getTimesSecs(double* process_real_time,
1002 double* process_user_time,
1003 double* process_system_time) {
1004 struct tms ticks;
1005 clock_t real_ticks = times(&ticks);
1006
1007 if (real_ticks == (clock_t) (-1)) {
1008 return false;
1009 } else {
1010 double ticks_per_second = (double) clock_tics_per_sec;
1011 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1012 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1013 *process_real_time = ((double) real_ticks) / ticks_per_second;
1014
1015 return true;
1016 }
1017 }
1018
1019
1020 char * os::local_time_string(char *buf, size_t buflen) {
1021 struct tm t;
1022 time_t long_time;
1023 time(&long_time);
1024 localtime_r(&long_time, &t);
1025 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1026 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1027 t.tm_hour, t.tm_min, t.tm_sec);
1028 return buf;
1029 }
1030
1031 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
1032 return localtime_r(clock, res);
1033 }
1034
1035 ////////////////////////////////////////////////////////////////////////////////
1036 // runtime exit support
1037
1038 // Note: os::shutdown() might be called very early during initialization, or
1039 // called from signal handler. Before adding something to os::shutdown(), make
1040 // sure it is async-safe and can handle partially initialized VM.
1041 void os::shutdown() {
1042
1043 // allow PerfMemory to attempt cleanup of any persistent resources
1044 perfMemory_exit();
1045
1046 // needs to remove object in file system
1047 AttachListener::abort();
1048
1049 // flush buffered output, finish log files
1050 ostream_abort();
1051
1052 // Check for abort hook
1053 abort_hook_t abort_hook = Arguments::abort_hook();
1054 if (abort_hook != NULL) {
1055 abort_hook();
1056 }
1057
1058 }
1059
1060 // Note: os::abort() might be called very early during initialization, or
1061 // called from signal handler. Before adding something to os::abort(), make
1062 // sure it is async-safe and can handle partially initialized VM.
1063 void os::abort(bool dump_core, void* siginfo, const void* context) {
1064 os::shutdown();
1065 if (dump_core) {
1066 ::abort(); // dump core
1067 }
1068
1069 ::exit(1);
1070 }
1071
1072 // Die immediately, no exit hook, no abort hook, no cleanup.
1073 // Dump a core file, if possible, for debugging.
1074 void os::die() {
1075 if (TestUnresponsiveErrorHandler && !CreateCoredumpOnCrash) {
1076 // For TimeoutInErrorHandlingTest.java, we just kill the VM
1077 // and don't take the time to generate a core file.
1078 os::signal_raise(SIGKILL);
1079 } else {
1080 // _exit() on BsdThreads only kills current thread
1081 ::abort();
1082 }
1083 }
1084
1085 // Information of current thread in variety of formats
1086 pid_t os::Bsd::gettid() {
1087 int retval = -1;
1088
1089 #ifdef __APPLE__ // XNU kernel
1090 mach_port_t port = mach_thread_self();
1091 guarantee(MACH_PORT_VALID(port), "just checking");
1092 mach_port_deallocate(mach_task_self(), port);
1093 return (pid_t)port;
1094
1095 #else
1096 #ifdef __FreeBSD__
1097 retval = syscall(SYS_thr_self);
1098 #else
1099 #ifdef __OpenBSD__
1100 retval = syscall(SYS_getthrid);
1101 #else
1102 #ifdef __NetBSD__
1103 retval = (pid_t) syscall(SYS__lwp_self);
1104 #endif
1105 #endif
1106 #endif
1107 #endif
1108
1109 if (retval == -1) {
1110 return getpid();
1111 }
1112 }
1113
1114 intx os::current_thread_id() {
1115 #ifdef __APPLE__
1116 return (intx)os::Bsd::gettid();
1117 #else
1118 return (intx)::pthread_self();
1119 #endif
1120 }
1121
1122 int os::current_process_id() {
1123 return (int)(getpid());
1124 }
1125
1126 // DLL functions
1127
1128 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1129
1130 // This must be hard coded because it's the system's temporary
1131 // directory not the java application's temp directory, ala java.io.tmpdir.
1132 #ifdef __APPLE__
1133 // macosx has a secure per-user temporary directory
1134 char temp_path_storage[PATH_MAX];
1135 const char* os::get_temp_directory() {
1136 static char *temp_path = NULL;
1137 if (temp_path == NULL) {
1138 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
1139 if (pathSize == 0 || pathSize > PATH_MAX) {
1140 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
1141 }
1142 temp_path = temp_path_storage;
1143 }
1144 return temp_path;
1145 }
1146 #else // __APPLE__
1147 const char* os::get_temp_directory() { return "/tmp"; }
1148 #endif // __APPLE__
1149
1150 // check if addr is inside libjvm.so
1151 bool os::address_is_in_vm(address addr) {
1152 static address libjvm_base_addr;
1153 Dl_info dlinfo;
1154
1155 if (libjvm_base_addr == NULL) {
1156 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) {
1157 libjvm_base_addr = (address)dlinfo.dli_fbase;
1158 }
1159 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1160 }
1161
1162 if (dladdr((void *)addr, &dlinfo) != 0) {
1163 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1164 }
1165
1166 return false;
1167 }
1168
1169
1170 #define MACH_MAXSYMLEN 256
1171
1172 bool os::dll_address_to_function_name(address addr, char *buf,
1173 int buflen, int *offset,
1174 bool demangle) {
1175 // buf is not optional, but offset is optional
1176 assert(buf != NULL, "sanity check");
1177
1178 Dl_info dlinfo;
1179 char localbuf[MACH_MAXSYMLEN];
1180
1181 if (dladdr((void*)addr, &dlinfo) != 0) {
1182 // see if we have a matching symbol
1183 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) {
1184 if (!(demangle && Decoder::demangle(dlinfo.dli_sname, buf, buflen))) {
1185 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1186 }
1187 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1188 return true;
1189 }
1190 // no matching symbol so try for just file info
1191 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) {
1192 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1193 buf, buflen, offset, dlinfo.dli_fname, demangle)) {
1194 return true;
1195 }
1196 }
1197
1198 // Handle non-dynamic manually:
1199 if (dlinfo.dli_fbase != NULL &&
1200 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset,
1201 dlinfo.dli_fbase)) {
1202 if (!(demangle && Decoder::demangle(localbuf, buf, buflen))) {
1203 jio_snprintf(buf, buflen, "%s", localbuf);
1204 }
1205 return true;
1206 }
1207 }
1208 buf[0] = '\0';
1209 if (offset != NULL) *offset = -1;
1210 return false;
1211 }
1212
1213 // ported from solaris version
1214 bool os::dll_address_to_library_name(address addr, char* buf,
1215 int buflen, int* offset) {
1216 // buf is not optional, but offset is optional
1217 assert(buf != NULL, "sanity check");
1218
1219 Dl_info dlinfo;
1220
1221 if (dladdr((void*)addr, &dlinfo) != 0) {
1222 if (dlinfo.dli_fname != NULL) {
1223 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1224 }
1225 if (dlinfo.dli_fbase != NULL && offset != NULL) {
1226 *offset = addr - (address)dlinfo.dli_fbase;
1227 }
1228 return true;
1229 }
1230
1231 buf[0] = '\0';
1232 if (offset) *offset = -1;
1233 return false;
1234 }
1235
1236 // Loads .dll/.so and
1237 // in case of error it checks if .dll/.so was built for the
1238 // same architecture as Hotspot is running on
1239
1240 #ifdef __APPLE__
1241 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1242 #ifdef STATIC_BUILD
1243 return os::get_default_process_handle();
1244 #else
1245 log_info(os)("attempting shared library load of %s", filename);
1246
1247 void * result= ::dlopen(filename, RTLD_LAZY);
1248 if (result != NULL) {
1249 Events::log(NULL, "Loaded shared library %s", filename);
1250 // Successful loading
1251 log_info(os)("shared library load of %s was successful", filename);
1252 return result;
1253 }
1254
1255 const char* error_report = ::dlerror();
1256 if (error_report == NULL) {
1257 error_report = "dlerror returned no error description";
1258 }
1259 if (ebuf != NULL && ebuflen > 0) {
1260 // Read system error message into ebuf
1261 ::strncpy(ebuf, error_report, ebuflen-1);
1262 ebuf[ebuflen-1]='\0';
1263 }
1264 Events::log(NULL, "Loading shared library %s failed, %s", filename, error_report);
1265 log_info(os)("shared library load of %s failed, %s", filename, error_report);
1266
1267 return NULL;
1268 #endif // STATIC_BUILD
1269 }
1270 #else
1271 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1272 #ifdef STATIC_BUILD
1273 return os::get_default_process_handle();
1274 #else
1275 log_info(os)("attempting shared library load of %s", filename);
1276 void * result= ::dlopen(filename, RTLD_LAZY);
1277 if (result != NULL) {
1278 Events::log(NULL, "Loaded shared library %s", filename);
1279 // Successful loading
1280 log_info(os)("shared library load of %s was successful", filename);
1281 return result;
1282 }
1283
1284 Elf32_Ehdr elf_head;
1285
1286 const char* const error_report = ::dlerror();
1287 if (error_report == NULL) {
1288 error_report = "dlerror returned no error description";
1289 }
1290 if (ebuf != NULL && ebuflen > 0) {
1291 // Read system error message into ebuf
1292 ::strncpy(ebuf, error_report, ebuflen-1);
1293 ebuf[ebuflen-1]='\0';
1294 }
1295 Events::log(NULL, "Loading shared library %s failed, %s", filename, error_report);
1296 log_info(os)("shared library load of %s failed, %s", filename, error_report);
1297
1298 int diag_msg_max_length=ebuflen-strlen(ebuf);
1299 char* diag_msg_buf=ebuf+strlen(ebuf);
1300
1301 if (diag_msg_max_length==0) {
1302 // No more space in ebuf for additional diagnostics message
1303 return NULL;
1304 }
1305
1306
1307 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1308
1309 if (file_descriptor < 0) {
1310 // Can't open library, report dlerror() message
1311 return NULL;
1312 }
1313
1314 bool failed_to_read_elf_head=
1315 (sizeof(elf_head)!=
1316 (::read(file_descriptor, &elf_head,sizeof(elf_head))));
1317
1318 ::close(file_descriptor);
1319 if (failed_to_read_elf_head) {
1320 // file i/o error - report dlerror() msg
1321 return NULL;
1322 }
1323
1324 typedef struct {
1325 Elf32_Half code; // Actual value as defined in elf.h
1326 Elf32_Half compat_class; // Compatibility of archs at VM's sense
1327 char elf_class; // 32 or 64 bit
1328 char endianess; // MSB or LSB
1329 char* name; // String representation
1330 } arch_t;
1331
1332 #ifndef EM_486
1333 #define EM_486 6 /* Intel 80486 */
1334 #endif
1335
1336 #ifndef EM_MIPS_RS3_LE
1337 #define EM_MIPS_RS3_LE 10 /* MIPS */
1338 #endif
1339
1340 #ifndef EM_PPC64
1341 #define EM_PPC64 21 /* PowerPC64 */
1342 #endif
1343
1344 #ifndef EM_S390
1345 #define EM_S390 22 /* IBM System/390 */
1346 #endif
1347
1348 #ifndef EM_IA_64
1349 #define EM_IA_64 50 /* HP/Intel IA-64 */
1350 #endif
1351
1352 #ifndef EM_X86_64
1353 #define EM_X86_64 62 /* AMD x86-64 */
1354 #endif
1355
1356 static const arch_t arch_array[]={
1357 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1358 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1359 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
1360 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
1361 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
1362 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
1363 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"},
1364 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
1365 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
1366 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
1367 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
1368 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
1369 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
1370 };
1371
1372 #if (defined IA32)
1373 static Elf32_Half running_arch_code=EM_386;
1374 #elif (defined AMD64)
1375 static Elf32_Half running_arch_code=EM_X86_64;
1376 #elif (defined IA64)
1377 static Elf32_Half running_arch_code=EM_IA_64;
1378 #elif (defined __powerpc64__)
1379 static Elf32_Half running_arch_code=EM_PPC64;
1380 #elif (defined __powerpc__)
1381 static Elf32_Half running_arch_code=EM_PPC;
1382 #elif (defined ARM)
1383 static Elf32_Half running_arch_code=EM_ARM;
1384 #elif (defined S390)
1385 static Elf32_Half running_arch_code=EM_S390;
1386 #elif (defined ALPHA)
1387 static Elf32_Half running_arch_code=EM_ALPHA;
1388 #elif (defined MIPSEL)
1389 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
1390 #elif (defined PARISC)
1391 static Elf32_Half running_arch_code=EM_PARISC;
1392 #elif (defined MIPS)
1393 static Elf32_Half running_arch_code=EM_MIPS;
1394 #elif (defined M68K)
1395 static Elf32_Half running_arch_code=EM_68K;
1396 #else
1397 #error Method os::dll_load requires that one of following is defined:\
1398 IA32, AMD64, IA64, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
1399 #endif
1400
1401 // Identify compatability class for VM's architecture and library's architecture
1402 // Obtain string descriptions for architectures
1403
1404 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
1405 int running_arch_index=-1;
1406
1407 for (unsigned int i=0; i < ARRAY_SIZE(arch_array); i++) {
1408 if (running_arch_code == arch_array[i].code) {
1409 running_arch_index = i;
1410 }
1411 if (lib_arch.code == arch_array[i].code) {
1412 lib_arch.compat_class = arch_array[i].compat_class;
1413 lib_arch.name = arch_array[i].name;
1414 }
1415 }
1416
1417 assert(running_arch_index != -1,
1418 "Didn't find running architecture code (running_arch_code) in arch_array");
1419 if (running_arch_index == -1) {
1420 // Even though running architecture detection failed
1421 // we may still continue with reporting dlerror() message
1422 return NULL;
1423 }
1424
1425 if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
1426 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
1427 return NULL;
1428 }
1429
1430 #ifndef S390
1431 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
1432 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
1433 return NULL;
1434 }
1435 #endif // !S390
1436
1437 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
1438 if (lib_arch.name!=NULL) {
1439 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1440 " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
1441 lib_arch.name, arch_array[running_arch_index].name);
1442 } else {
1443 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1444 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
1445 lib_arch.code,
1446 arch_array[running_arch_index].name);
1447 }
1448 }
1449
1450 return NULL;
1451 #endif // STATIC_BUILD
1452 }
1453 #endif // !__APPLE__
1454
1455 void* os::get_default_process_handle() {
1456 #ifdef __APPLE__
1457 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY
1458 // to avoid finding unexpected symbols on second (or later)
1459 // loads of a library.
1460 return (void*)::dlopen(NULL, RTLD_FIRST);
1461 #else
1462 return (void*)::dlopen(NULL, RTLD_LAZY);
1463 #endif
1464 }
1465
1466 // XXX: Do we need a lock around this as per Linux?
1467 void* os::dll_lookup(void* handle, const char* name) {
1468 return dlsym(handle, name);
1469 }
1470
1471 int _print_dll_info_cb(const char * name, address base_address, address top_address, void * param) {
1472 outputStream * out = (outputStream *) param;
1473 out->print_cr(INTPTR_FORMAT " \t%s", (intptr_t)base_address, name);
1474 return 0;
1475 }
1476
1477 void os::print_dll_info(outputStream *st) {
1478 st->print_cr("Dynamic libraries:");
1479 if (get_loaded_modules_info(_print_dll_info_cb, (void *)st)) {
1480 st->print_cr("Error: Cannot print dynamic libraries.");
1481 }
1482 }
1483
1484 int os::get_loaded_modules_info(os::LoadedModulesCallbackFunc callback, void *param) {
1485 #ifdef RTLD_DI_LINKMAP
1486 Dl_info dli;
1487 void *handle;
1488 Link_map *map;
1489 Link_map *p;
1490
1491 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 ||
1492 dli.dli_fname == NULL) {
1493 return 1;
1494 }
1495 handle = dlopen(dli.dli_fname, RTLD_LAZY);
1496 if (handle == NULL) {
1497 return 1;
1498 }
1499 dlinfo(handle, RTLD_DI_LINKMAP, &map);
1500 if (map == NULL) {
1501 dlclose(handle);
1502 return 1;
1503 }
1504
1505 while (map->l_prev != NULL)
1506 map = map->l_prev;
1507
1508 while (map != NULL) {
1509 // Value for top_address is returned as 0 since we don't have any information about module size
1510 if (callback(map->l_name, (address)map->l_addr, (address)0, param)) {
1511 dlclose(handle);
1512 return 1;
1513 }
1514 map = map->l_next;
1515 }
1516
1517 dlclose(handle);
1518 #elif defined(__APPLE__)
1519 for (uint32_t i = 1; i < _dyld_image_count(); i++) {
1520 // Value for top_address is returned as 0 since we don't have any information about module size
1521 if (callback(_dyld_get_image_name(i), (address)_dyld_get_image_header(i), (address)0, param)) {
1522 return 1;
1523 }
1524 }
1525 return 0;
1526 #else
1527 return 1;
1528 #endif
1529 }
1530
1531 void os::get_summary_os_info(char* buf, size_t buflen) {
1532 // These buffers are small because we want this to be brief
1533 // and not use a lot of stack while generating the hs_err file.
1534 char os[100];
1535 size_t size = sizeof(os);
1536 int mib_kern[] = { CTL_KERN, KERN_OSTYPE };
1537 if (sysctl(mib_kern, 2, os, &size, NULL, 0) < 0) {
1538 #ifdef __APPLE__
1539 strncpy(os, "Darwin", sizeof(os));
1540 #elif __OpenBSD__
1541 strncpy(os, "OpenBSD", sizeof(os));
1542 #else
1543 strncpy(os, "BSD", sizeof(os));
1544 #endif
1545 }
1546
1547 char release[100];
1548 size = sizeof(release);
1549 int mib_release[] = { CTL_KERN, KERN_OSRELEASE };
1550 if (sysctl(mib_release, 2, release, &size, NULL, 0) < 0) {
1551 // if error, leave blank
1552 strncpy(release, "", sizeof(release));
1553 }
1554 snprintf(buf, buflen, "%s %s", os, release);
1555 }
1556
1557 void os::print_os_info_brief(outputStream* st) {
1558 os::Posix::print_uname_info(st);
1559 }
1560
1561 void os::print_os_info(outputStream* st) {
1562 st->print("OS:");
1563
1564 os::Posix::print_uname_info(st);
1565
1566 os::Bsd::print_uptime_info(st);
1567
1568 os::Posix::print_rlimit_info(st);
1569
1570 os::Posix::print_load_average(st);
1571
1572 VM_Version::print_platform_virtualization_info(st);
1573 }
1574
1575 void os::pd_print_cpu_info(outputStream* st, char* buf, size_t buflen) {
1576 // Nothing to do for now.
1577 }
1578
1579 void os::get_summary_cpu_info(char* buf, size_t buflen) {
1580 unsigned int mhz;
1581 size_t size = sizeof(mhz);
1582 int mib[] = { CTL_HW, HW_CPU_FREQ };
1583 if (sysctl(mib, 2, &mhz, &size, NULL, 0) < 0) {
1584 mhz = 1; // looks like an error but can be divided by
1585 } else {
1586 mhz /= 1000000; // reported in millions
1587 }
1588
1589 char model[100];
1590 size = sizeof(model);
1591 int mib_model[] = { CTL_HW, HW_MODEL };
1592 if (sysctl(mib_model, 2, model, &size, NULL, 0) < 0) {
1593 strncpy(model, cpu_arch, sizeof(model));
1594 }
1595
1596 char machine[100];
1597 size = sizeof(machine);
1598 int mib_machine[] = { CTL_HW, HW_MACHINE };
1599 if (sysctl(mib_machine, 2, machine, &size, NULL, 0) < 0) {
1600 strncpy(machine, "", sizeof(machine));
1601 }
1602
1603 snprintf(buf, buflen, "%s %s %d MHz", model, machine, mhz);
1604 }
1605
1606 void os::print_memory_info(outputStream* st) {
1607 xsw_usage swap_usage;
1608 size_t size = sizeof(swap_usage);
1609
1610 st->print("Memory:");
1611 st->print(" %dk page", os::vm_page_size()>>10);
1612
1613 st->print(", physical " UINT64_FORMAT "k",
1614 os::physical_memory() >> 10);
1615 st->print("(" UINT64_FORMAT "k free)",
1616 os::available_memory() >> 10);
1617
1618 if((sysctlbyname("vm.swapusage", &swap_usage, &size, NULL, 0) == 0) || (errno == ENOMEM)) {
1619 if (size >= offset_of(xsw_usage, xsu_used)) {
1620 st->print(", swap " UINT64_FORMAT "k",
1621 ((julong) swap_usage.xsu_total) >> 10);
1622 st->print("(" UINT64_FORMAT "k free)",
1623 ((julong) swap_usage.xsu_avail) >> 10);
1624 }
1625 }
1626
1627 st->cr();
1628 }
1629
1630 static void print_signal_handler(outputStream* st, int sig,
1631 char* buf, size_t buflen);
1632
1633 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1634 st->print_cr("Signal Handlers:");
1635 print_signal_handler(st, SIGSEGV, buf, buflen);
1636 print_signal_handler(st, SIGBUS , buf, buflen);
1637 print_signal_handler(st, SIGFPE , buf, buflen);
1638 print_signal_handler(st, SIGPIPE, buf, buflen);
1639 print_signal_handler(st, SIGXFSZ, buf, buflen);
1640 print_signal_handler(st, SIGILL , buf, buflen);
1641 print_signal_handler(st, SR_signum, buf, buflen);
1642 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1643 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1644 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1645 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1646 }
1647
1648 static char saved_jvm_path[MAXPATHLEN] = {0};
1649
1650 // Find the full path to the current module, libjvm
1651 void os::jvm_path(char *buf, jint buflen) {
1652 // Error checking.
1653 if (buflen < MAXPATHLEN) {
1654 assert(false, "must use a large-enough buffer");
1655 buf[0] = '\0';
1656 return;
1657 }
1658 // Lazy resolve the path to current module.
1659 if (saved_jvm_path[0] != 0) {
1660 strcpy(buf, saved_jvm_path);
1661 return;
1662 }
1663
1664 char dli_fname[MAXPATHLEN];
1665 bool ret = dll_address_to_library_name(
1666 CAST_FROM_FN_PTR(address, os::jvm_path),
1667 dli_fname, sizeof(dli_fname), NULL);
1668 assert(ret, "cannot locate libjvm");
1669 char *rp = NULL;
1670 if (ret && dli_fname[0] != '\0') {
1671 rp = os::Posix::realpath(dli_fname, buf, buflen);
1672 }
1673 if (rp == NULL) {
1674 return;
1675 }
1676
1677 if (Arguments::sun_java_launcher_is_altjvm()) {
1678 // Support for the java launcher's '-XXaltjvm=<path>' option. Typical
1679 // value for buf is "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so"
1680 // or "<JAVA_HOME>/jre/lib/<vmtype>/libjvm.dylib". If "/jre/lib/"
1681 // appears at the right place in the string, then assume we are
1682 // installed in a JDK and we're done. Otherwise, check for a
1683 // JAVA_HOME environment variable and construct a path to the JVM
1684 // being overridden.
1685
1686 const char *p = buf + strlen(buf) - 1;
1687 for (int count = 0; p > buf && count < 5; ++count) {
1688 for (--p; p > buf && *p != '/'; --p)
1689 /* empty */ ;
1690 }
1691
1692 if (strncmp(p, "/jre/lib/", 9) != 0) {
1693 // Look for JAVA_HOME in the environment.
1694 char* java_home_var = ::getenv("JAVA_HOME");
1695 if (java_home_var != NULL && java_home_var[0] != 0) {
1696 char* jrelib_p;
1697 int len;
1698
1699 // Check the current module name "libjvm"
1700 p = strrchr(buf, '/');
1701 assert(strstr(p, "/libjvm") == p, "invalid library name");
1702
1703 rp = os::Posix::realpath(java_home_var, buf, buflen);
1704 if (rp == NULL) {
1705 return;
1706 }
1707
1708 // determine if this is a legacy image or modules image
1709 // modules image doesn't have "jre" subdirectory
1710 len = strlen(buf);
1711 assert(len < buflen, "Ran out of buffer space");
1712 jrelib_p = buf + len;
1713
1714 // Add the appropriate library subdir
1715 snprintf(jrelib_p, buflen-len, "/jre/lib");
1716 if (0 != access(buf, F_OK)) {
1717 snprintf(jrelib_p, buflen-len, "/lib");
1718 }
1719
1720 // Add the appropriate client or server subdir
1721 len = strlen(buf);
1722 jrelib_p = buf + len;
1723 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
1724 if (0 != access(buf, F_OK)) {
1725 snprintf(jrelib_p, buflen-len, "%s", "");
1726 }
1727
1728 // If the path exists within JAVA_HOME, add the JVM library name
1729 // to complete the path to JVM being overridden. Otherwise fallback
1730 // to the path to the current library.
1731 if (0 == access(buf, F_OK)) {
1732 // Use current module name "libjvm"
1733 len = strlen(buf);
1734 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
1735 } else {
1736 // Fall back to path of current library
1737 rp = os::Posix::realpath(dli_fname, buf, buflen);
1738 if (rp == NULL) {
1739 return;
1740 }
1741 }
1742 }
1743 }
1744 }
1745
1746 strncpy(saved_jvm_path, buf, MAXPATHLEN);
1747 saved_jvm_path[MAXPATHLEN - 1] = '\0';
1748 }
1749
1750 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1751 // no prefix required, not even "_"
1752 }
1753
1754 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1755 // no suffix required
1756 }
1757
1758 ////////////////////////////////////////////////////////////////////////////////
1759 // sun.misc.Signal support
1760
1761 static void UserHandler(int sig, void *siginfo, void *context) {
1762 // Ctrl-C is pressed during error reporting, likely because the error
1763 // handler fails to abort. Let VM die immediately.
1764 if (sig == SIGINT && VMError::is_error_reported()) {
1765 os::die();
1766 }
1767
1768 os::signal_notify(sig);
1769 }
1770
1771 void* os::user_handler() {
1772 return CAST_FROM_FN_PTR(void*, UserHandler);
1773 }
1774
1775 extern "C" {
1776 typedef void (*sa_handler_t)(int);
1777 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1778 }
1779
1780 void* os::signal(int signal_number, void* handler) {
1781 struct sigaction sigAct, oldSigAct;
1782
1783 sigfillset(&(sigAct.sa_mask));
1784 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
1785 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1786
1787 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1788 // -1 means registration failed
1789 return (void *)-1;
1790 }
1791
1792 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1793 }
1794
1795 void os::signal_raise(int signal_number) {
1796 ::raise(signal_number);
1797 }
1798
1799 // The following code is moved from os.cpp for making this
1800 // code platform specific, which it is by its very nature.
1801
1802 // Will be modified when max signal is changed to be dynamic
1803 int os::sigexitnum_pd() {
1804 return NSIG;
1805 }
1806
1807 // a counter for each possible signal value
1808 static volatile jint pending_signals[NSIG+1] = { 0 };
1809 static Semaphore* sig_sem = NULL;
1810
1811 static void jdk_misc_signal_init() {
1812 // Initialize signal structures
1813 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
1814
1815 // Initialize signal semaphore
1816 sig_sem = new Semaphore();
1817 }
1818
1819 void os::signal_notify(int sig) {
1820 if (sig_sem != NULL) {
1821 Atomic::inc(&pending_signals[sig]);
1822 sig_sem->signal();
1823 } else {
1824 // Signal thread is not created with ReduceSignalUsage and jdk_misc_signal_init
1825 // initialization isn't called.
1826 assert(ReduceSignalUsage, "signal semaphore should be created");
1827 }
1828 }
1829
1830 static int check_pending_signals() {
1831 for (;;) {
1832 for (int i = 0; i < NSIG + 1; i++) {
1833 jint n = pending_signals[i];
1834 if (n > 0 && n == Atomic::cmpxchg(&pending_signals[i], n, n - 1)) {
1835 return i;
1836 }
1837 }
1838 JavaThread *thread = JavaThread::current();
1839 ThreadBlockInVM tbivm(thread);
1840
1841 bool threadIsSuspended;
1842 do {
1843 thread->set_suspend_equivalent();
1844 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
1845 sig_sem->wait();
1846
1847 // were we externally suspended while we were waiting?
1848 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
1849 if (threadIsSuspended) {
1850 // The semaphore has been incremented, but while we were waiting
1851 // another thread suspended us. We don't want to continue running
1852 // while suspended because that would surprise the thread that
1853 // suspended us.
1854 sig_sem->signal();
1855
1856 thread->java_suspend_self();
1857 }
1858 } while (threadIsSuspended);
1859 }
1860 }
1861
1862 int os::signal_wait() {
1863 return check_pending_signals();
1864 }
1865
1866 ////////////////////////////////////////////////////////////////////////////////
1867 // Virtual Memory
1868
1869 int os::vm_page_size() {
1870 // Seems redundant as all get out
1871 assert(os::Bsd::page_size() != -1, "must call os::init");
1872 return os::Bsd::page_size();
1873 }
1874
1875 // Solaris allocates memory by pages.
1876 int os::vm_allocation_granularity() {
1877 assert(os::Bsd::page_size() != -1, "must call os::init");
1878 return os::Bsd::page_size();
1879 }
1880
1881 static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
1882 int err) {
1883 warning("INFO: os::commit_memory(" INTPTR_FORMAT ", " SIZE_FORMAT
1884 ", %d) failed; error='%s' (errno=%d)", (intptr_t)addr, size, exec,
1885 os::errno_name(err), err);
1886 }
1887
1888 // NOTE: Bsd kernel does not really reserve the pages for us.
1889 // All it does is to check if there are enough free pages
1890 // left at the time of mmap(). This could be a potential
1891 // problem.
1892 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
1893 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
1894 #ifdef __OpenBSD__
1895 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
1896 Events::log(NULL, "Protecting memory [" INTPTR_FORMAT "," INTPTR_FORMAT "] with protection modes %x", p2i(addr), p2i(addr+size), prot);
1897 if (::mprotect(addr, size, prot) == 0) {
1898 return true;
1899 }
1900 #else
1901 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
1902 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
1903 if (res != (uintptr_t) MAP_FAILED) {
1904 return true;
1905 }
1906 #endif
1907
1908 // Warn about any commit errors we see in non-product builds just
1909 // in case mmap() doesn't work as described on the man page.
1910 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);)
1911
1912 return false;
1913 }
1914
1915 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
1916 bool exec) {
1917 // alignment_hint is ignored on this OS
1918 return pd_commit_memory(addr, size, exec);
1919 }
1920
1921 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
1922 const char* mesg) {
1923 assert(mesg != NULL, "mesg must be specified");
1924 if (!pd_commit_memory(addr, size, exec)) {
1925 // add extra info in product mode for vm_exit_out_of_memory():
1926 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
1927 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, "%s", mesg);
1928 }
1929 }
1930
1931 void os::pd_commit_memory_or_exit(char* addr, size_t size,
1932 size_t alignment_hint, bool exec,
1933 const char* mesg) {
1934 // alignment_hint is ignored on this OS
1935 pd_commit_memory_or_exit(addr, size, exec, mesg);
1936 }
1937
1938 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
1939 }
1940
1941 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
1942 ::madvise(addr, bytes, MADV_DONTNEED);
1943 }
1944
1945 void os::numa_make_global(char *addr, size_t bytes) {
1946 }
1947
1948 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
1949 }
1950
1951 bool os::numa_topology_changed() { return false; }
1952
1953 size_t os::numa_get_groups_num() {
1954 return 1;
1955 }
1956
1957 int os::numa_get_group_id() {
1958 return 0;
1959 }
1960
1961 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
1962 if (size > 0) {
1963 ids[0] = 0;
1964 return 1;
1965 }
1966 return 0;
1967 }
1968
1969 int os::numa_get_group_id_for_address(const void* address) {
1970 return 0;
1971 }
1972
1973 bool os::get_page_info(char *start, page_info* info) {
1974 return false;
1975 }
1976
1977 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
1978 return end;
1979 }
1980
1981
1982 bool os::pd_uncommit_memory(char* addr, size_t size) {
1983 #ifdef __OpenBSD__
1984 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
1985 Events::log(NULL, "Protecting memory [" INTPTR_FORMAT "," INTPTR_FORMAT "] with PROT_NONE", p2i(addr), p2i(addr+size));
1986 return ::mprotect(addr, size, PROT_NONE) == 0;
1987 #else
1988 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
1989 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
1990 return res != (uintptr_t) MAP_FAILED;
1991 #endif
1992 }
1993
1994 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
1995 return os::commit_memory(addr, size, !ExecMem);
1996 }
1997
1998 // If this is a growable mapping, remove the guard pages entirely by
1999 // munmap()ping them. If not, just call uncommit_memory().
2000 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2001 return os::uncommit_memory(addr, size);
2002 }
2003
2004 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2005 // at 'requested_addr'. If there are existing memory mappings at the same
2006 // location, however, they will be overwritten. If 'fixed' is false,
2007 // 'requested_addr' is only treated as a hint, the return value may or
2008 // may not start from the requested address. Unlike Bsd mmap(), this
2009 // function returns NULL to indicate failure.
2010 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2011 char * addr;
2012 int flags;
2013
2014 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2015 if (fixed) {
2016 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2017 flags |= MAP_FIXED;
2018 }
2019
2020 // Map reserved/uncommitted pages PROT_NONE so we fail early if we
2021 // touch an uncommitted page. Otherwise, the read/write might
2022 // succeed if we have enough swap space to back the physical page.
2023 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE,
2024 flags, -1, 0);
2025
2026 return addr == MAP_FAILED ? NULL : addr;
2027 }
2028
2029 static int anon_munmap(char * addr, size_t size) {
2030 return ::munmap(addr, size) == 0;
2031 }
2032
2033 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
2034 size_t alignment_hint) {
2035 return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2036 }
2037
2038 bool os::pd_release_memory(char* addr, size_t size) {
2039 return anon_munmap(addr, size);
2040 }
2041
2042 static bool bsd_mprotect(char* addr, size_t size, int prot) {
2043 // Bsd wants the mprotect address argument to be page aligned.
2044 char* bottom = (char*)align_down((intptr_t)addr, os::Bsd::page_size());
2045
2046 // According to SUSv3, mprotect() should only be used with mappings
2047 // established by mmap(), and mmap() always maps whole pages. Unaligned
2048 // 'addr' likely indicates problem in the VM (e.g. trying to change
2049 // protection of malloc'ed or statically allocated memory). Check the
2050 // caller if you hit this assert.
2051 assert(addr == bottom, "sanity check");
2052
2053 size = align_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2054 Events::log(NULL, "Protecting memory [" INTPTR_FORMAT "," INTPTR_FORMAT "] with protection modes %x", p2i(bottom), p2i(bottom+size), prot);
2055 return ::mprotect(bottom, size, prot) == 0;
2056 }
2057
2058 // Set protections specified
2059 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2060 bool is_committed) {
2061 unsigned int p = 0;
2062 switch (prot) {
2063 case MEM_PROT_NONE: p = PROT_NONE; break;
2064 case MEM_PROT_READ: p = PROT_READ; break;
2065 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
2066 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2067 default:
2068 ShouldNotReachHere();
2069 }
2070 // is_committed is unused.
2071 return bsd_mprotect(addr, bytes, p);
2072 }
2073
2074 bool os::guard_memory(char* addr, size_t size) {
2075 return bsd_mprotect(addr, size, PROT_NONE);
2076 }
2077
2078 bool os::unguard_memory(char* addr, size_t size) {
2079 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
2080 }
2081
2082 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
2083 return false;
2084 }
2085
2086 // Large page support
2087
2088 static size_t _large_page_size = 0;
2089
2090 void os::large_page_init() {
2091 }
2092
2093
2094 char* os::pd_reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) {
2095 fatal("os::reserve_memory_special should not be called on BSD.");
2096 return NULL;
2097 }
2098
2099 bool os::pd_release_memory_special(char* base, size_t bytes) {
2100 fatal("os::release_memory_special should not be called on BSD.");
2101 return false;
2102 }
2103
2104 size_t os::large_page_size() {
2105 return _large_page_size;
2106 }
2107
2108 bool os::can_commit_large_page_memory() {
2109 // Does not matter, we do not support huge pages.
2110 return false;
2111 }
2112
2113 bool os::can_execute_large_page_memory() {
2114 // Does not matter, we do not support huge pages.
2115 return false;
2116 }
2117
2118 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr, int file_desc) {
2119 assert(file_desc >= 0, "file_desc is not valid");
2120 char* result = pd_attempt_reserve_memory_at(bytes, requested_addr);
2121 if (result != NULL) {
2122 if (replace_existing_mapping_with_file_mapping(result, bytes, file_desc) == NULL) {
2123 vm_exit_during_initialization(err_msg("Error in mapping Java heap at the given filesystem directory"));
2124 }
2125 }
2126 return result;
2127 }
2128
2129 // Reserve memory at an arbitrary address, only if that area is
2130 // available (and not reserved for something else).
2131
2132 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2133 // Assert only that the size is a multiple of the page size, since
2134 // that's all that mmap requires, and since that's all we really know
2135 // about at this low abstraction level. If we need higher alignment,
2136 // we can either pass an alignment to this method or verify alignment
2137 // in one of the methods further up the call chain. See bug 5044738.
2138 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2139
2140 // Repeatedly allocate blocks until the block is allocated at the
2141 // right spot.
2142
2143 // Bsd mmap allows caller to pass an address as hint; give it a try first,
2144 // if kernel honors the hint then we can return immediately.
2145 char * addr = anon_mmap(requested_addr, bytes, false);
2146 if (addr == requested_addr) {
2147 return requested_addr;
2148 }
2149
2150 if (addr != NULL) {
2151 // mmap() is successful but it fails to reserve at the requested address
2152 anon_munmap(addr, bytes);
2153 }
2154
2155 return NULL;
2156 }
2157
2158 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2159 void os::infinite_sleep() {
2160 while (true) { // sleep forever ...
2161 ::sleep(100); // ... 100 seconds at a time
2162 }
2163 }
2164
2165 // Used to convert frequent JVM_Yield() to nops
2166 bool os::dont_yield() {
2167 return DontYieldALot;
2168 }
2169
2170 void os::naked_yield() {
2171 sched_yield();
2172 }
2173
2174 ////////////////////////////////////////////////////////////////////////////////
2175 // thread priority support
2176
2177 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2178 // only supports dynamic priority, static priority must be zero. For real-time
2179 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
2180 // However, for large multi-threaded applications, SCHED_RR is not only slower
2181 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2182 // of 5 runs - Sep 2005).
2183 //
2184 // The following code actually changes the niceness of kernel-thread/LWP. It
2185 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
2186 // not the entire user process, and user level threads are 1:1 mapped to kernel
2187 // threads. It has always been the case, but could change in the future. For
2188 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2189 // It is only used when ThreadPriorityPolicy=1 and may require system level permission
2190 // (e.g., root privilege or CAP_SYS_NICE capability).
2191
2192 #if !defined(__APPLE__)
2193 int os::java_to_os_priority[CriticalPriority + 1] = {
2194 19, // 0 Entry should never be used
2195
2196 0, // 1 MinPriority
2197 3, // 2
2198 6, // 3
2199
2200 10, // 4
2201 15, // 5 NormPriority
2202 18, // 6
2203
2204 21, // 7
2205 25, // 8
2206 28, // 9 NearMaxPriority
2207
2208 31, // 10 MaxPriority
2209
2210 31 // 11 CriticalPriority
2211 };
2212 #else
2213 // Using Mach high-level priority assignments
2214 int os::java_to_os_priority[CriticalPriority + 1] = {
2215 0, // 0 Entry should never be used (MINPRI_USER)
2216
2217 27, // 1 MinPriority
2218 28, // 2
2219 29, // 3
2220
2221 30, // 4
2222 31, // 5 NormPriority (BASEPRI_DEFAULT)
2223 32, // 6
2224
2225 33, // 7
2226 34, // 8
2227 35, // 9 NearMaxPriority
2228
2229 36, // 10 MaxPriority
2230
2231 36 // 11 CriticalPriority
2232 };
2233 #endif
2234
2235 static int prio_init() {
2236 if (ThreadPriorityPolicy == 1) {
2237 if (geteuid() != 0) {
2238 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy) && !FLAG_IS_JIMAGE_RESOURCE(ThreadPriorityPolicy)) {
2239 warning("-XX:ThreadPriorityPolicy=1 may require system level permission, " \
2240 "e.g., being the root user. If the necessary permission is not " \
2241 "possessed, changes to priority will be silently ignored.");
2242 }
2243 }
2244 }
2245 if (UseCriticalJavaThreadPriority) {
2246 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2247 }
2248 return 0;
2249 }
2250
2251 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2252 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) return OS_OK;
2253
2254 #ifdef __OpenBSD__
2255 // OpenBSD pthread_setprio starves low priority threads
2256 return OS_OK;
2257 #elif defined(__FreeBSD__)
2258 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2259 return (ret == 0) ? OS_OK : OS_ERR;
2260 #elif defined(__APPLE__) || defined(__NetBSD__)
2261 struct sched_param sp;
2262 int policy;
2263
2264 if (pthread_getschedparam(thread->osthread()->pthread_id(), &policy, &sp) != 0) {
2265 return OS_ERR;
2266 }
2267
2268 sp.sched_priority = newpri;
2269 if (pthread_setschedparam(thread->osthread()->pthread_id(), policy, &sp) != 0) {
2270 return OS_ERR;
2271 }
2272
2273 return OS_OK;
2274 #else
2275 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2276 return (ret == 0) ? OS_OK : OS_ERR;
2277 #endif
2278 }
2279
2280 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2281 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) {
2282 *priority_ptr = java_to_os_priority[NormPriority];
2283 return OS_OK;
2284 }
2285
2286 errno = 0;
2287 #if defined(__OpenBSD__) || defined(__FreeBSD__)
2288 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2289 #elif defined(__APPLE__) || defined(__NetBSD__)
2290 int policy;
2291 struct sched_param sp;
2292
2293 int res = pthread_getschedparam(thread->osthread()->pthread_id(), &policy, &sp);
2294 if (res != 0) {
2295 *priority_ptr = -1;
2296 return OS_ERR;
2297 } else {
2298 *priority_ptr = sp.sched_priority;
2299 return OS_OK;
2300 }
2301 #else
2302 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2303 #endif
2304 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2305 }
2306
2307 ////////////////////////////////////////////////////////////////////////////////
2308 // suspend/resume support
2309
2310 // The low-level signal-based suspend/resume support is a remnant from the
2311 // old VM-suspension that used to be for java-suspension, safepoints etc,
2312 // within hotspot. Currently used by JFR's OSThreadSampler
2313 //
2314 // The remaining code is greatly simplified from the more general suspension
2315 // code that used to be used.
2316 //
2317 // The protocol is quite simple:
2318 // - suspend:
2319 // - sends a signal to the target thread
2320 // - polls the suspend state of the osthread using a yield loop
2321 // - target thread signal handler (SR_handler) sets suspend state
2322 // and blocks in sigsuspend until continued
2323 // - resume:
2324 // - sets target osthread state to continue
2325 // - sends signal to end the sigsuspend loop in the SR_handler
2326 //
2327 // Note that the SR_lock plays no role in this suspend/resume protocol,
2328 // but is checked for NULL in SR_handler as a thread termination indicator.
2329 // The SR_lock is, however, used by JavaThread::java_suspend()/java_resume() APIs.
2330 //
2331 // Note that resume_clear_context() and suspend_save_context() are needed
2332 // by SR_handler(), so that fetch_frame_from_context() works,
2333 // which in part is used by:
2334 // - Forte Analyzer: AsyncGetCallTrace()
2335 // - StackBanging: get_frame_at_stack_banging_point()
2336
2337 static void resume_clear_context(OSThread *osthread) {
2338 osthread->set_ucontext(NULL);
2339 osthread->set_siginfo(NULL);
2340 }
2341
2342 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2343 osthread->set_ucontext(context);
2344 osthread->set_siginfo(siginfo);
2345 }
2346
2347 // Handler function invoked when a thread's execution is suspended or
2348 // resumed. We have to be careful that only async-safe functions are
2349 // called here (Note: most pthread functions are not async safe and
2350 // should be avoided.)
2351 //
2352 // Note: sigwait() is a more natural fit than sigsuspend() from an
2353 // interface point of view, but sigwait() prevents the signal hander
2354 // from being run. libpthread would get very confused by not having
2355 // its signal handlers run and prevents sigwait()'s use with the
2356 // mutex granting granting signal.
2357 //
2358 // Currently only ever called on the VMThread or JavaThread
2359 //
2360 #ifdef __APPLE__
2361 static OSXSemaphore sr_semaphore;
2362 #else
2363 static PosixSemaphore sr_semaphore;
2364 #endif
2365
2366 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2367 // Save and restore errno to avoid confusing native code with EINTR
2368 // after sigsuspend.
2369 int old_errno = errno;
2370
2371 Thread* thread = Thread::current_or_null_safe();
2372 assert(thread != NULL, "Missing current thread in SR_handler");
2373
2374 // On some systems we have seen signal delivery get "stuck" until the signal
2375 // mask is changed as part of thread termination. Check that the current thread
2376 // has not already terminated (via SR_lock()) - else the following assertion
2377 // will fail because the thread is no longer a JavaThread as the ~JavaThread
2378 // destructor has completed.
2379
2380 if (thread->SR_lock() == NULL) {
2381 return;
2382 }
2383
2384 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
2385
2386 OSThread* osthread = thread->osthread();
2387
2388 os::SuspendResume::State current = osthread->sr.state();
2389 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
2390 suspend_save_context(osthread, siginfo, context);
2391
2392 // attempt to switch the state, we assume we had a SUSPEND_REQUEST
2393 os::SuspendResume::State state = osthread->sr.suspended();
2394 if (state == os::SuspendResume::SR_SUSPENDED) {
2395 sigset_t suspend_set; // signals for sigsuspend()
2396
2397 // get current set of blocked signals and unblock resume signal
2398 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2399 sigdelset(&suspend_set, SR_signum);
2400
2401 sr_semaphore.signal();
2402 // wait here until we are resumed
2403 while (1) {
2404 sigsuspend(&suspend_set);
2405
2406 os::SuspendResume::State result = osthread->sr.running();
2407 if (result == os::SuspendResume::SR_RUNNING) {
2408 sr_semaphore.signal();
2409 break;
2410 } else if (result != os::SuspendResume::SR_SUSPENDED) {
2411 ShouldNotReachHere();
2412 }
2413 }
2414
2415 } else if (state == os::SuspendResume::SR_RUNNING) {
2416 // request was cancelled, continue
2417 } else {
2418 ShouldNotReachHere();
2419 }
2420
2421 resume_clear_context(osthread);
2422 } else if (current == os::SuspendResume::SR_RUNNING) {
2423 // request was cancelled, continue
2424 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
2425 // ignore
2426 } else {
2427 // ignore
2428 }
2429
2430 errno = old_errno;
2431 }
2432
2433
2434 static int SR_initialize() {
2435 struct sigaction act;
2436 char *s;
2437 // Get signal number to use for suspend/resume
2438 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2439 int sig = ::strtol(s, 0, 10);
2440 if (sig > MAX2(SIGSEGV, SIGBUS) && // See 4355769.
2441 sig < NSIG) { // Must be legal signal and fit into sigflags[].
2442 SR_signum = sig;
2443 } else {
2444 warning("You set _JAVA_SR_SIGNUM=%d. It must be in range [%d, %d]. Using %d instead.",
2445 sig, MAX2(SIGSEGV, SIGBUS)+1, NSIG-1, SR_signum);
2446 }
2447 }
2448
2449 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2450 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2451
2452 sigemptyset(&SR_sigset);
2453 sigaddset(&SR_sigset, SR_signum);
2454
2455 // Set up signal handler for suspend/resume
2456 act.sa_flags = SA_RESTART|SA_SIGINFO;
2457 act.sa_handler = (void (*)(int)) SR_handler;
2458
2459 // SR_signum is blocked by default.
2460 // 4528190 - We also need to block pthread restart signal (32 on all
2461 // supported Bsd platforms). Note that BsdThreads need to block
2462 // this signal for all threads to work properly. So we don't have
2463 // to use hard-coded signal number when setting up the mask.
2464 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2465
2466 if (sigaction(SR_signum, &act, 0) == -1) {
2467 return -1;
2468 }
2469
2470 // Save signal flag
2471 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2472 return 0;
2473 }
2474
2475 static int sr_notify(OSThread* osthread) {
2476 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2477 assert_status(status == 0, status, "pthread_kill");
2478 return status;
2479 }
2480
2481 // "Randomly" selected value for how long we want to spin
2482 // before bailing out on suspending a thread, also how often
2483 // we send a signal to a thread we want to resume
2484 static const int RANDOMLY_LARGE_INTEGER = 1000000;
2485 static const int RANDOMLY_LARGE_INTEGER2 = 100;
2486
2487 // returns true on success and false on error - really an error is fatal
2488 // but this seems the normal response to library errors
2489 static bool do_suspend(OSThread* osthread) {
2490 assert(osthread->sr.is_running(), "thread should be running");
2491 assert(!sr_semaphore.trywait(), "semaphore has invalid state");
2492
2493 // mark as suspended and send signal
2494 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
2495 // failed to switch, state wasn't running?
2496 ShouldNotReachHere();
2497 return false;
2498 }
2499
2500 if (sr_notify(osthread) != 0) {
2501 ShouldNotReachHere();
2502 }
2503
2504 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
2505 while (true) {
2506 if (sr_semaphore.timedwait(2)) {
2507 break;
2508 } else {
2509 // timeout
2510 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
2511 if (cancelled == os::SuspendResume::SR_RUNNING) {
2512 return false;
2513 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
2514 // make sure that we consume the signal on the semaphore as well
2515 sr_semaphore.wait();
2516 break;
2517 } else {
2518 ShouldNotReachHere();
2519 return false;
2520 }
2521 }
2522 }
2523
2524 guarantee(osthread->sr.is_suspended(), "Must be suspended");
2525 return true;
2526 }
2527
2528 static void do_resume(OSThread* osthread) {
2529 assert(osthread->sr.is_suspended(), "thread should be suspended");
2530 assert(!sr_semaphore.trywait(), "invalid semaphore state");
2531
2532 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
2533 // failed to switch to WAKEUP_REQUEST
2534 ShouldNotReachHere();
2535 return;
2536 }
2537
2538 while (true) {
2539 if (sr_notify(osthread) == 0) {
2540 if (sr_semaphore.timedwait(2)) {
2541 if (osthread->sr.is_running()) {
2542 return;
2543 }
2544 }
2545 } else {
2546 ShouldNotReachHere();
2547 }
2548 }
2549
2550 guarantee(osthread->sr.is_running(), "Must be running!");
2551 }
2552
2553 ///////////////////////////////////////////////////////////////////////////////////
2554 // signal handling (except suspend/resume)
2555
2556 // This routine may be used by user applications as a "hook" to catch signals.
2557 // The user-defined signal handler must pass unrecognized signals to this
2558 // routine, and if it returns true (non-zero), then the signal handler must
2559 // return immediately. If the flag "abort_if_unrecognized" is true, then this
2560 // routine will never retun false (zero), but instead will execute a VM panic
2561 // routine kill the process.
2562 //
2563 // If this routine returns false, it is OK to call it again. This allows
2564 // the user-defined signal handler to perform checks either before or after
2565 // the VM performs its own checks. Naturally, the user code would be making
2566 // a serious error if it tried to handle an exception (such as a null check
2567 // or breakpoint) that the VM was generating for its own correct operation.
2568 //
2569 // This routine may recognize any of the following kinds of signals:
2570 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
2571 // It should be consulted by handlers for any of those signals.
2572 //
2573 // The caller of this routine must pass in the three arguments supplied
2574 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
2575 // field of the structure passed to sigaction(). This routine assumes that
2576 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
2577 //
2578 // Note that the VM will print warnings if it detects conflicting signal
2579 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
2580 //
2581 extern "C" JNIEXPORT int JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
2582 void* ucontext,
2583 int abort_if_unrecognized);
2584
2585 static void signalHandler(int sig, siginfo_t* info, void* uc) {
2586 assert(info != NULL && uc != NULL, "it must be old kernel");
2587 int orig_errno = errno; // Preserve errno value over signal handler.
2588 JVM_handle_bsd_signal(sig, info, uc, true);
2589 errno = orig_errno;
2590 }
2591
2592
2593 // This boolean allows users to forward their own non-matching signals
2594 // to JVM_handle_bsd_signal, harmlessly.
2595 bool os::Bsd::signal_handlers_are_installed = false;
2596
2597 // For signal-chaining
2598 bool os::Bsd::libjsig_is_loaded = false;
2599 typedef struct sigaction *(*get_signal_t)(int);
2600 get_signal_t os::Bsd::get_signal_action = NULL;
2601
2602 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
2603 struct sigaction *actp = NULL;
2604
2605 if (libjsig_is_loaded) {
2606 // Retrieve the old signal handler from libjsig
2607 actp = (*get_signal_action)(sig);
2608 }
2609 if (actp == NULL) {
2610 // Retrieve the preinstalled signal handler from jvm
2611 actp = os::Posix::get_preinstalled_handler(sig);
2612 }
2613
2614 return actp;
2615 }
2616
2617 static bool call_chained_handler(struct sigaction *actp, int sig,
2618 siginfo_t *siginfo, void *context) {
2619 // Call the old signal handler
2620 if (actp->sa_handler == SIG_DFL) {
2621 // It's more reasonable to let jvm treat it as an unexpected exception
2622 // instead of taking the default action.
2623 return false;
2624 } else if (actp->sa_handler != SIG_IGN) {
2625 if ((actp->sa_flags & SA_NODEFER) == 0) {
2626 // automaticlly block the signal
2627 sigaddset(&(actp->sa_mask), sig);
2628 }
2629
2630 sa_handler_t hand;
2631 sa_sigaction_t sa;
2632 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
2633 // retrieve the chained handler
2634 if (siginfo_flag_set) {
2635 sa = actp->sa_sigaction;
2636 } else {
2637 hand = actp->sa_handler;
2638 }
2639
2640 if ((actp->sa_flags & SA_RESETHAND) != 0) {
2641 actp->sa_handler = SIG_DFL;
2642 }
2643
2644 // try to honor the signal mask
2645 sigset_t oset;
2646 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
2647
2648 // call into the chained handler
2649 if (siginfo_flag_set) {
2650 (*sa)(sig, siginfo, context);
2651 } else {
2652 (*hand)(sig);
2653 }
2654
2655 // restore the signal mask
2656 pthread_sigmask(SIG_SETMASK, &oset, 0);
2657 }
2658 // Tell jvm's signal handler the signal is taken care of.
2659 return true;
2660 }
2661
2662 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
2663 bool chained = false;
2664 // signal-chaining
2665 if (UseSignalChaining) {
2666 struct sigaction *actp = get_chained_signal_action(sig);
2667 if (actp != NULL) {
2668 chained = call_chained_handler(actp, sig, siginfo, context);
2669 }
2670 }
2671 return chained;
2672 }
2673
2674 // for diagnostic
2675 int sigflags[NSIG];
2676
2677 int os::Bsd::get_our_sigflags(int sig) {
2678 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
2679 return sigflags[sig];
2680 }
2681
2682 void os::Bsd::set_our_sigflags(int sig, int flags) {
2683 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
2684 if (sig > 0 && sig < NSIG) {
2685 sigflags[sig] = flags;
2686 }
2687 }
2688
2689 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
2690 // Check for overwrite.
2691 struct sigaction oldAct;
2692 sigaction(sig, (struct sigaction*)NULL, &oldAct);
2693
2694 void* oldhand = oldAct.sa_sigaction
2695 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
2696 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
2697 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
2698 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
2699 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
2700 if (AllowUserSignalHandlers || !set_installed) {
2701 // Do not overwrite; user takes responsibility to forward to us.
2702 return;
2703 } else if (UseSignalChaining) {
2704 // save the old handler in jvm
2705 os::Posix::save_preinstalled_handler(sig, oldAct);
2706 // libjsig also interposes the sigaction() call below and saves the
2707 // old sigaction on it own.
2708 } else {
2709 fatal("Encountered unexpected pre-existing sigaction handler "
2710 "%#lx for signal %d.", (long)oldhand, sig);
2711 }
2712 }
2713
2714 struct sigaction sigAct;
2715 sigfillset(&(sigAct.sa_mask));
2716 sigAct.sa_handler = SIG_DFL;
2717 if (!set_installed) {
2718 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
2719 } else {
2720 sigAct.sa_sigaction = signalHandler;
2721 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
2722 }
2723 #ifdef __APPLE__
2724 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV
2725 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages"
2726 // if the signal handler declares it will handle it on alternate stack.
2727 // Notice we only declare we will handle it on alt stack, but we are not
2728 // actually going to use real alt stack - this is just a workaround.
2729 // Please see ux_exception.c, method catch_mach_exception_raise for details
2730 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c
2731 if (sig == SIGSEGV) {
2732 sigAct.sa_flags |= SA_ONSTACK;
2733 }
2734 #endif
2735
2736 // Save flags, which are set by ours
2737 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
2738 sigflags[sig] = sigAct.sa_flags;
2739
2740 int ret = sigaction(sig, &sigAct, &oldAct);
2741 assert(ret == 0, "check");
2742
2743 void* oldhand2 = oldAct.sa_sigaction
2744 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
2745 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
2746 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
2747 }
2748
2749 // install signal handlers for signals that HotSpot needs to
2750 // handle in order to support Java-level exception handling.
2751
2752 void os::Bsd::install_signal_handlers() {
2753 if (!signal_handlers_are_installed) {
2754 signal_handlers_are_installed = true;
2755
2756 // signal-chaining
2757 typedef void (*signal_setting_t)();
2758 signal_setting_t begin_signal_setting = NULL;
2759 signal_setting_t end_signal_setting = NULL;
2760 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
2761 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
2762 if (begin_signal_setting != NULL) {
2763 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
2764 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
2765 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
2766 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
2767 libjsig_is_loaded = true;
2768 assert(UseSignalChaining, "should enable signal-chaining");
2769 }
2770 if (libjsig_is_loaded) {
2771 // Tell libjsig jvm is setting signal handlers
2772 (*begin_signal_setting)();
2773 }
2774
2775 set_signal_handler(SIGSEGV, true);
2776 set_signal_handler(SIGPIPE, true);
2777 set_signal_handler(SIGBUS, true);
2778 set_signal_handler(SIGILL, true);
2779 set_signal_handler(SIGFPE, true);
2780 set_signal_handler(SIGXFSZ, true);
2781
2782 #if defined(__APPLE__)
2783 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
2784 // signals caught and handled by the JVM. To work around this, we reset the mach task
2785 // signal handler that's placed on our process by CrashReporter. This disables
2786 // CrashReporter-based reporting.
2787 //
2788 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
2789 // on caught fatal signals.
2790 //
2791 // Additionally, gdb installs both standard BSD signal handlers, and mach exception
2792 // handlers. By replacing the existing task exception handler, we disable gdb's mach
2793 // exception handling, while leaving the standard BSD signal handlers functional.
2794 kern_return_t kr;
2795 kr = task_set_exception_ports(mach_task_self(),
2796 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
2797 MACH_PORT_NULL,
2798 EXCEPTION_STATE_IDENTITY,
2799 MACHINE_THREAD_STATE);
2800
2801 assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
2802 #endif
2803
2804 if (libjsig_is_loaded) {
2805 // Tell libjsig jvm finishes setting signal handlers
2806 (*end_signal_setting)();
2807 }
2808
2809 // We don't activate signal checker if libjsig is in place, we trust ourselves
2810 // and if UserSignalHandler is installed all bets are off
2811 if (CheckJNICalls) {
2812 if (libjsig_is_loaded) {
2813 log_debug(jni, resolve)("Info: libjsig is activated, all active signal checking is disabled");
2814 check_signals = false;
2815 }
2816 if (AllowUserSignalHandlers) {
2817 log_debug(jni, resolve)("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
2818 check_signals = false;
2819 }
2820 }
2821 }
2822 }
2823
2824
2825 /////
2826 // glibc on Bsd platform uses non-documented flag
2827 // to indicate, that some special sort of signal
2828 // trampoline is used.
2829 // We will never set this flag, and we should
2830 // ignore this flag in our diagnostic
2831 #ifdef SIGNIFICANT_SIGNAL_MASK
2832 #undef SIGNIFICANT_SIGNAL_MASK
2833 #endif
2834 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
2835
2836 static const char* get_signal_handler_name(address handler,
2837 char* buf, int buflen) {
2838 int offset;
2839 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
2840 if (found) {
2841 // skip directory names
2842 const char *p1, *p2;
2843 p1 = buf;
2844 size_t len = strlen(os::file_separator());
2845 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
2846 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
2847 } else {
2848 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
2849 }
2850 return buf;
2851 }
2852
2853 static void print_signal_handler(outputStream* st, int sig,
2854 char* buf, size_t buflen) {
2855 struct sigaction sa;
2856
2857 sigaction(sig, NULL, &sa);
2858
2859 // See comment for SIGNIFICANT_SIGNAL_MASK define
2860 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
2861
2862 st->print("%s: ", os::exception_name(sig, buf, buflen));
2863
2864 address handler = (sa.sa_flags & SA_SIGINFO)
2865 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
2866 : CAST_FROM_FN_PTR(address, sa.sa_handler);
2867
2868 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
2869 st->print("SIG_DFL");
2870 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
2871 st->print("SIG_IGN");
2872 } else {
2873 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
2874 }
2875
2876 st->print(", sa_mask[0]=");
2877 os::Posix::print_signal_set_short(st, &sa.sa_mask);
2878
2879 address rh = VMError::get_resetted_sighandler(sig);
2880 // May be, handler was resetted by VMError?
2881 if (rh != NULL) {
2882 handler = rh;
2883 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
2884 }
2885
2886 st->print(", sa_flags=");
2887 os::Posix::print_sa_flags(st, sa.sa_flags);
2888
2889 // Check: is it our handler?
2890 if (handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
2891 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
2892 // It is our signal handler
2893 // check for flags, reset system-used one!
2894 if ((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
2895 st->print(
2896 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
2897 os::Bsd::get_our_sigflags(sig));
2898 }
2899 }
2900 st->cr();
2901 }
2902
2903
2904 #define DO_SIGNAL_CHECK(sig) \
2905 do { \
2906 if (!sigismember(&check_signal_done, sig)) { \
2907 os::Bsd::check_signal_handler(sig); \
2908 } \
2909 } while (0)
2910
2911 // This method is a periodic task to check for misbehaving JNI applications
2912 // under CheckJNI, we can add any periodic checks here
2913
2914 void os::run_periodic_checks() {
2915
2916 if (check_signals == false) return;
2917
2918 // SEGV and BUS if overridden could potentially prevent
2919 // generation of hs*.log in the event of a crash, debugging
2920 // such a case can be very challenging, so we absolutely
2921 // check the following for a good measure:
2922 DO_SIGNAL_CHECK(SIGSEGV);
2923 DO_SIGNAL_CHECK(SIGILL);
2924 DO_SIGNAL_CHECK(SIGFPE);
2925 DO_SIGNAL_CHECK(SIGBUS);
2926 DO_SIGNAL_CHECK(SIGPIPE);
2927 DO_SIGNAL_CHECK(SIGXFSZ);
2928
2929
2930 // ReduceSignalUsage allows the user to override these handlers
2931 // see comments at the very top and jvm_md.h
2932 if (!ReduceSignalUsage) {
2933 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
2934 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
2935 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
2936 DO_SIGNAL_CHECK(BREAK_SIGNAL);
2937 }
2938
2939 DO_SIGNAL_CHECK(SR_signum);
2940 }
2941
2942 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
2943
2944 static os_sigaction_t os_sigaction = NULL;
2945
2946 void os::Bsd::check_signal_handler(int sig) {
2947 char buf[O_BUFLEN];
2948 address jvmHandler = NULL;
2949
2950
2951 struct sigaction act;
2952 if (os_sigaction == NULL) {
2953 // only trust the default sigaction, in case it has been interposed
2954 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
2955 if (os_sigaction == NULL) return;
2956 }
2957
2958 os_sigaction(sig, (struct sigaction*)NULL, &act);
2959
2960
2961 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
2962
2963 address thisHandler = (act.sa_flags & SA_SIGINFO)
2964 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
2965 : CAST_FROM_FN_PTR(address, act.sa_handler);
2966
2967
2968 switch (sig) {
2969 case SIGSEGV:
2970 case SIGBUS:
2971 case SIGFPE:
2972 case SIGPIPE:
2973 case SIGILL:
2974 case SIGXFSZ:
2975 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
2976 break;
2977
2978 case SHUTDOWN1_SIGNAL:
2979 case SHUTDOWN2_SIGNAL:
2980 case SHUTDOWN3_SIGNAL:
2981 case BREAK_SIGNAL:
2982 jvmHandler = (address)user_handler();
2983 break;
2984
2985 default:
2986 if (sig == SR_signum) {
2987 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
2988 } else {
2989 return;
2990 }
2991 break;
2992 }
2993
2994 if (thisHandler != jvmHandler) {
2995 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
2996 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
2997 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
2998 // No need to check this sig any longer
2999 sigaddset(&check_signal_done, sig);
3000 // Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN
3001 if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) {
3002 tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell",
3003 exception_name(sig, buf, O_BUFLEN));
3004 }
3005 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3006 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3007 tty->print("expected:");
3008 os::Posix::print_sa_flags(tty, os::Bsd::get_our_sigflags(sig));
3009 tty->cr();
3010 tty->print(" found:");
3011 os::Posix::print_sa_flags(tty, act.sa_flags);
3012 tty->cr();
3013 // No need to check this sig any longer
3014 sigaddset(&check_signal_done, sig);
3015 }
3016
3017 // Dump all the signal
3018 if (sigismember(&check_signal_done, sig)) {
3019 print_signal_handlers(tty, buf, O_BUFLEN);
3020 }
3021 }
3022
3023 extern void report_error(char* file_name, int line_no, char* title,
3024 char* format, ...);
3025
3026 // this is called _before_ the most of global arguments have been parsed
3027 void os::init(void) {
3028 char dummy; // used to get a guess on initial stack address
3029
3030 clock_tics_per_sec = CLK_TCK;
3031
3032 init_random(1234567);
3033
3034 Bsd::set_page_size(getpagesize());
3035 if (Bsd::page_size() == -1) {
3036 fatal("os_bsd.cpp: os::init: sysconf failed (%s)", os::strerror(errno));
3037 }
3038 init_page_sizes((size_t) Bsd::page_size());
3039
3040 Bsd::initialize_system_info();
3041
3042 // _main_thread points to the thread that created/loaded the JVM.
3043 Bsd::_main_thread = pthread_self();
3044
3045 Bsd::clock_init();
3046 initial_time_count = javaTimeNanos();
3047
3048 os::Posix::init();
3049 }
3050
3051 // To install functions for atexit system call
3052 extern "C" {
3053 static void perfMemory_exit_helper() {
3054 perfMemory_exit();
3055 }
3056 }
3057
3058 // this is called _after_ the global arguments have been parsed
3059 jint os::init_2(void) {
3060
3061 // This could be set after os::Posix::init() but all platforms
3062 // have to set it the same so we have to mirror Solaris.
3063 DEBUG_ONLY(os::set_mutex_init_done();)
3064
3065 os::Posix::init_2();
3066
3067 // initialize suspend/resume support - must do this before signal_sets_init()
3068 if (SR_initialize() != 0) {
3069 perror("SR_initialize failed");
3070 return JNI_ERR;
3071 }
3072
3073 Bsd::signal_sets_init();
3074 Bsd::install_signal_handlers();
3075 // Initialize data for jdk.internal.misc.Signal
3076 if (!ReduceSignalUsage) {
3077 jdk_misc_signal_init();
3078 }
3079
3080 // Check and sets minimum stack sizes against command line options
3081 if (Posix::set_minimum_stack_sizes() == JNI_ERR) {
3082 return JNI_ERR;
3083 }
3084
3085 // Not supported.
3086 FLAG_SET_ERGO(UseNUMA, false);
3087 FLAG_SET_ERGO(UseNUMAInterleaving, false);
3088
3089 if (MaxFDLimit) {
3090 // set the number of file descriptors to max. print out error
3091 // if getrlimit/setrlimit fails but continue regardless.
3092 struct rlimit nbr_files;
3093 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3094 if (status != 0) {
3095 log_info(os)("os::init_2 getrlimit failed: %s", os::strerror(errno));
3096 } else {
3097 nbr_files.rlim_cur = nbr_files.rlim_max;
3098
3099 #ifdef __APPLE__
3100 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3101 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3102 // be used instead
3103 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3104 #endif
3105
3106 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3107 if (status != 0) {
3108 log_info(os)("os::init_2 setrlimit failed: %s", os::strerror(errno));
3109 }
3110 }
3111 }
3112
3113 // at-exit methods are called in the reverse order of their registration.
3114 // atexit functions are called on return from main or as a result of a
3115 // call to exit(3C). There can be only 32 of these functions registered
3116 // and atexit() does not set errno.
3117
3118 if (PerfAllowAtExitRegistration) {
3119 // only register atexit functions if PerfAllowAtExitRegistration is set.
3120 // atexit functions can be delayed until process exit time, which
3121 // can be problematic for embedded VM situations. Embedded VMs should
3122 // call DestroyJavaVM() to assure that VM resources are released.
3123
3124 // note: perfMemory_exit_helper atexit function may be removed in
3125 // the future if the appropriate cleanup code can be added to the
3126 // VM_Exit VMOperation's doit method.
3127 if (atexit(perfMemory_exit_helper) != 0) {
3128 warning("os::init_2 atexit(perfMemory_exit_helper) failed");
3129 }
3130 }
3131
3132 // initialize thread priority policy
3133 prio_init();
3134
3135 #ifdef __APPLE__
3136 // dynamically link to objective c gc registration
3137 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3138 if (handleLibObjc != NULL) {
3139 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3140 }
3141 #endif
3142
3143 return JNI_OK;
3144 }
3145
3146 int os::active_processor_count() {
3147 // User has overridden the number of active processors
3148 if (ActiveProcessorCount > 0) {
3149 log_trace(os)("active_processor_count: "
3150 "active processor count set by user : %d",
3151 ActiveProcessorCount);
3152 return ActiveProcessorCount;
3153 }
3154
3155 return _processor_count;
3156 }
3157
3158 #ifdef __APPLE__
3159 uint os::processor_id() {
3160 // Get the initial APIC id and return the associated processor id. The initial APIC
3161 // id is limited to 8-bits, which means we can have at most 256 unique APIC ids. If
3162 // the system has more processors (or the initial APIC ids are discontiguous) the
3163 // APIC id will be truncated and more than one processor will potentially share the
3164 // same processor id. This is not optimal, but unlikely to happen in practice. Should
3165 // this become a real problem we could switch to using x2APIC ids, which are 32-bit
3166 // wide. However, note that x2APIC is Intel-specific, and the wider number space
3167 // would require a more complicated mapping approach.
3168 uint eax = 0x1;
3169 uint ebx;
3170 uint ecx = 0;
3171 uint edx;
3172
3173 __asm__ ("cpuid\n\t" : "+a" (eax), "+b" (ebx), "+c" (ecx), "+d" (edx) : );
3174
3175 uint apic_id = (ebx >> 24) & (processor_id_map_size - 1);
3176 int processor_id = Atomic::load(&processor_id_map[apic_id]);
3177
3178 while (processor_id < 0) {
3179 // Assign processor id to APIC id
3180 processor_id = Atomic::cmpxchg(&processor_id_map[apic_id], processor_id_unassigned, processor_id_assigning);
3181 if (processor_id == processor_id_unassigned) {
3182 processor_id = Atomic::fetch_and_add(&processor_id_next, 1) % os::processor_count();
3183 Atomic::store(&processor_id_map[apic_id], processor_id);
3184 }
3185 }
3186
3187 assert(processor_id >= 0 && processor_id < os::processor_count(), "invalid processor id");
3188
3189 return (uint)processor_id;
3190 }
3191 #endif
3192
3193 void os::set_native_thread_name(const char *name) {
3194 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3195 // This is only supported in Snow Leopard and beyond
3196 if (name != NULL) {
3197 // Add a "Java: " prefix to the name
3198 char buf[MAXTHREADNAMESIZE];
3199 snprintf(buf, sizeof(buf), "Java: %s", name);
3200 pthread_setname_np(buf);
3201 }
3202 #endif
3203 }
3204
3205 bool os::bind_to_processor(uint processor_id) {
3206 // Not yet implemented.
3207 return false;
3208 }
3209
3210 void os::SuspendedThreadTask::internal_do_task() {
3211 if (do_suspend(_thread->osthread())) {
3212 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
3213 do_task(context);
3214 do_resume(_thread->osthread());
3215 }
3216 }
3217
3218 ////////////////////////////////////////////////////////////////////////////////
3219 // debug support
3220
3221 bool os::find(address addr, outputStream* st) {
3222 Dl_info dlinfo;
3223 memset(&dlinfo, 0, sizeof(dlinfo));
3224 if (dladdr(addr, &dlinfo) != 0) {
3225 st->print(INTPTR_FORMAT ": ", (intptr_t)addr);
3226 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) {
3227 st->print("%s+%#x", dlinfo.dli_sname,
3228 (uint)((uintptr_t)addr - (uintptr_t)dlinfo.dli_saddr));
3229 } else if (dlinfo.dli_fbase != NULL) {
3230 st->print("<offset %#x>", (uint)((uintptr_t)addr - (uintptr_t)dlinfo.dli_fbase));
3231 } else {
3232 st->print("<absolute address>");
3233 }
3234 if (dlinfo.dli_fname != NULL) {
3235 st->print(" in %s", dlinfo.dli_fname);
3236 }
3237 if (dlinfo.dli_fbase != NULL) {
3238 st->print(" at " INTPTR_FORMAT, (intptr_t)dlinfo.dli_fbase);
3239 }
3240 st->cr();
3241
3242 if (Verbose) {
3243 // decode some bytes around the PC
3244 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
3245 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size());
3246 address lowest = (address) dlinfo.dli_sname;
3247 if (!lowest) lowest = (address) dlinfo.dli_fbase;
3248 if (begin < lowest) begin = lowest;
3249 Dl_info dlinfo2;
3250 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr
3251 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) {
3252 end = (address) dlinfo2.dli_saddr;
3253 }
3254 Disassembler::decode(begin, end, st);
3255 }
3256 return true;
3257 }
3258 return false;
3259 }
3260
3261 ////////////////////////////////////////////////////////////////////////////////
3262 // misc
3263
3264 // This does not do anything on Bsd. This is basically a hook for being
3265 // able to use structured exception handling (thread-local exception filters)
3266 // on, e.g., Win32.
3267 void os::os_exception_wrapper(java_call_t f, JavaValue* value,
3268 const methodHandle& method, JavaCallArguments* args,
3269 Thread* thread) {
3270 f(value, method, args, thread);
3271 }
3272
3273 void os::print_statistics() {
3274 }
3275
3276 bool os::message_box(const char* title, const char* message) {
3277 int i;
3278 fdStream err(defaultStream::error_fd());
3279 for (i = 0; i < 78; i++) err.print_raw("=");
3280 err.cr();
3281 err.print_raw_cr(title);
3282 for (i = 0; i < 78; i++) err.print_raw("-");
3283 err.cr();
3284 err.print_raw_cr(message);
3285 for (i = 0; i < 78; i++) err.print_raw("=");
3286 err.cr();
3287
3288 char buf[16];
3289 // Prevent process from exiting upon "read error" without consuming all CPU
3290 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3291
3292 return buf[0] == 'y' || buf[0] == 'Y';
3293 }
3294
3295 static inline struct timespec get_mtime(const char* filename) {
3296 struct stat st;
3297 int ret = os::stat(filename, &st);
3298 assert(ret == 0, "failed to stat() file '%s': %s", filename, os::strerror(errno));
3299 #ifdef __APPLE__
3300 return st.st_mtimespec;
3301 #else
3302 return st.st_mtim;
3303 #endif
3304 }
3305
3306 int os::compare_file_modified_times(const char* file1, const char* file2) {
3307 struct timespec filetime1 = get_mtime(file1);
3308 struct timespec filetime2 = get_mtime(file2);
3309 int diff = filetime1.tv_sec - filetime2.tv_sec;
3310 if (diff == 0) {
3311 return filetime1.tv_nsec - filetime2.tv_nsec;
3312 }
3313 return diff;
3314 }
3315
3316 // Is a (classpath) directory empty?
3317 bool os::dir_is_empty(const char* path) {
3318 DIR *dir = NULL;
3319 struct dirent *ptr;
3320
3321 dir = opendir(path);
3322 if (dir == NULL) return true;
3323
3324 // Scan the directory
3325 bool result = true;
3326 while (result && (ptr = readdir(dir)) != NULL) {
3327 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3328 result = false;
3329 }
3330 }
3331 closedir(dir);
3332 return result;
3333 }
3334
3335 // This code originates from JDK's sysOpen and open64_w
3336 // from src/solaris/hpi/src/system_md.c
3337
3338 int os::open(const char *path, int oflag, int mode) {
3339 if (strlen(path) > MAX_PATH - 1) {
3340 errno = ENAMETOOLONG;
3341 return -1;
3342 }
3343 int fd;
3344
3345 fd = ::open(path, oflag, mode);
3346 if (fd == -1) return -1;
3347
3348 // If the open succeeded, the file might still be a directory
3349 {
3350 struct stat buf;
3351 int ret = ::fstat(fd, &buf);
3352 int st_mode = buf.st_mode;
3353
3354 if (ret != -1) {
3355 if ((st_mode & S_IFMT) == S_IFDIR) {
3356 errno = EISDIR;
3357 ::close(fd);
3358 return -1;
3359 }
3360 } else {
3361 ::close(fd);
3362 return -1;
3363 }
3364 }
3365
3366 // All file descriptors that are opened in the JVM and not
3367 // specifically destined for a subprocess should have the
3368 // close-on-exec flag set. If we don't set it, then careless 3rd
3369 // party native code might fork and exec without closing all
3370 // appropriate file descriptors (e.g. as we do in closeDescriptors in
3371 // UNIXProcess.c), and this in turn might:
3372 //
3373 // - cause end-of-file to fail to be detected on some file
3374 // descriptors, resulting in mysterious hangs, or
3375 //
3376 // - might cause an fopen in the subprocess to fail on a system
3377 // suffering from bug 1085341.
3378 //
3379 // (Yes, the default setting of the close-on-exec flag is a Unix
3380 // design flaw)
3381 //
3382 // See:
3383 // 1085341: 32-bit stdio routines should support file descriptors >255
3384 // 4843136: (process) pipe file descriptor from Runtime.exec not being closed
3385 // 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
3386 //
3387 #ifdef FD_CLOEXEC
3388 {
3389 int flags = ::fcntl(fd, F_GETFD);
3390 if (flags != -1) {
3391 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
3392 }
3393 }
3394 #endif
3395
3396 return fd;
3397 }
3398
3399
3400 // create binary file, rewriting existing file if required
3401 int os::create_binary_file(const char* path, bool rewrite_existing) {
3402 int oflags = O_WRONLY | O_CREAT;
3403 if (!rewrite_existing) {
3404 oflags |= O_EXCL;
3405 }
3406 return ::open(path, oflags, S_IREAD | S_IWRITE);
3407 }
3408
3409 // return current position of file pointer
3410 jlong os::current_file_offset(int fd) {
3411 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
3412 }
3413
3414 // move file pointer to the specified offset
3415 jlong os::seek_to_file_offset(int fd, jlong offset) {
3416 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
3417 }
3418
3419 // This code originates from JDK's sysAvailable
3420 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
3421
3422 int os::available(int fd, jlong *bytes) {
3423 jlong cur, end;
3424 int mode;
3425 struct stat buf;
3426
3427 if (::fstat(fd, &buf) >= 0) {
3428 mode = buf.st_mode;
3429 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
3430 int n;
3431 if (::ioctl(fd, FIONREAD, &n) >= 0) {
3432 *bytes = n;
3433 return 1;
3434 }
3435 }
3436 }
3437 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
3438 return 0;
3439 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
3440 return 0;
3441 } else if (::lseek(fd, cur, SEEK_SET) == -1) {
3442 return 0;
3443 }
3444 *bytes = end - cur;
3445 return 1;
3446 }
3447
3448 // Map a block of memory.
3449 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
3450 char *addr, size_t bytes, bool read_only,
3451 bool allow_exec) {
3452 int prot;
3453 int flags;
3454
3455 if (read_only) {
3456 prot = PROT_READ;
3457 flags = MAP_SHARED;
3458 } else {
3459 prot = PROT_READ | PROT_WRITE;
3460 flags = MAP_PRIVATE;
3461 }
3462
3463 if (allow_exec) {
3464 prot |= PROT_EXEC;
3465 }
3466
3467 if (addr != NULL) {
3468 flags |= MAP_FIXED;
3469 }
3470
3471 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
3472 fd, file_offset);
3473 if (mapped_address == MAP_FAILED) {
3474 return NULL;
3475 }
3476 return mapped_address;
3477 }
3478
3479
3480 // Remap a block of memory.
3481 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
3482 char *addr, size_t bytes, bool read_only,
3483 bool allow_exec) {
3484 // same as map_memory() on this OS
3485 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
3486 allow_exec);
3487 }
3488
3489
3490 // Unmap a block of memory.
3491 bool os::pd_unmap_memory(char* addr, size_t bytes) {
3492 return munmap(addr, bytes) == 0;
3493 }
3494
3495 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
3496 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
3497 // of a thread.
3498 //
3499 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
3500 // the fast estimate available on the platform.
3501
3502 jlong os::current_thread_cpu_time() {
3503 #ifdef __APPLE__
3504 return os::thread_cpu_time(Thread::current(), true /* user + sys */);
3505 #else
3506 Unimplemented();
3507 return 0;
3508 #endif
3509 }
3510
3511 jlong os::thread_cpu_time(Thread* thread) {
3512 #ifdef __APPLE__
3513 return os::thread_cpu_time(thread, true /* user + sys */);
3514 #else
3515 Unimplemented();
3516 return 0;
3517 #endif
3518 }
3519
3520 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
3521 #ifdef __APPLE__
3522 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
3523 #else
3524 Unimplemented();
3525 return 0;
3526 #endif
3527 }
3528
3529 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
3530 #ifdef __APPLE__
3531 struct thread_basic_info tinfo;
3532 mach_msg_type_number_t tcount = THREAD_INFO_MAX;
3533 kern_return_t kr;
3534 thread_t mach_thread;
3535
3536 mach_thread = thread->osthread()->thread_id();
3537 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
3538 if (kr != KERN_SUCCESS) {
3539 return -1;
3540 }
3541
3542 if (user_sys_cpu_time) {
3543 jlong nanos;
3544 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
3545 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
3546 return nanos;
3547 } else {
3548 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
3549 }
3550 #else
3551 Unimplemented();
3552 return 0;
3553 #endif
3554 }
3555
3556
3557 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
3558 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
3559 info_ptr->may_skip_backward = false; // elapsed time not wall time
3560 info_ptr->may_skip_forward = false; // elapsed time not wall time
3561 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
3562 }
3563
3564 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
3565 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
3566 info_ptr->may_skip_backward = false; // elapsed time not wall time
3567 info_ptr->may_skip_forward = false; // elapsed time not wall time
3568 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
3569 }
3570
3571 bool os::is_thread_cpu_time_supported() {
3572 #ifdef __APPLE__
3573 return true;
3574 #else
3575 return false;
3576 #endif
3577 }
3578
3579 // System loadavg support. Returns -1 if load average cannot be obtained.
3580 // Bsd doesn't yet have a (official) notion of processor sets,
3581 // so just return the system wide load average.
3582 int os::loadavg(double loadavg[], int nelem) {
3583 return ::getloadavg(loadavg, nelem);
3584 }
3585
3586 void os::pause() {
3587 char filename[MAX_PATH];
3588 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
3589 jio_snprintf(filename, MAX_PATH, "%s", PauseAtStartupFile);
3590 } else {
3591 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
3592 }
3593
3594 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
3595 if (fd != -1) {
3596 struct stat buf;
3597 ::close(fd);
3598 while (::stat(filename, &buf) == 0) {
3599 (void)::poll(NULL, 0, 100);
3600 }
3601 } else {
3602 jio_fprintf(stderr,
3603 "Could not open pause file '%s', continuing immediately.\n", filename);
3604 }
3605 }
3606
3607 // Darwin has no "environ" in a dynamic library.
3608 #ifdef __APPLE__
3609 #include <crt_externs.h>
3610 #define environ (*_NSGetEnviron())
3611 #else
3612 extern char** environ;
3613 #endif
3614
3615 // Run the specified command in a separate process. Return its exit value,
3616 // or -1 on failure (e.g. can't fork a new process).
3617 // Unlike system(), this function can be called from signal handler. It
3618 // doesn't block SIGINT et al.
3619 int os::fork_and_exec(char* cmd, bool use_vfork_if_available) {
3620 const char * argv[4] = {"sh", "-c", cmd, NULL};
3621
3622 // fork() in BsdThreads/NPTL is not async-safe. It needs to run
3623 // pthread_atfork handlers and reset pthread library. All we need is a
3624 // separate process to execve. Make a direct syscall to fork process.
3625 // On IA64 there's no fork syscall, we have to use fork() and hope for
3626 // the best...
3627 pid_t pid = fork();
3628
3629 if (pid < 0) {
3630 // fork failed
3631 return -1;
3632
3633 } else if (pid == 0) {
3634 // child process
3635
3636 // execve() in BsdThreads will call pthread_kill_other_threads_np()
3637 // first to kill every thread on the thread list. Because this list is
3638 // not reset by fork() (see notes above), execve() will instead kill
3639 // every thread in the parent process. We know this is the only thread
3640 // in the new process, so make a system call directly.
3641 // IA64 should use normal execve() from glibc to match the glibc fork()
3642 // above.
3643 execve("/bin/sh", (char* const*)argv, environ);
3644
3645 // execve failed
3646 _exit(-1);
3647
3648 } else {
3649 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
3650 // care about the actual exit code, for now.
3651
3652 int status;
3653
3654 // Wait for the child process to exit. This returns immediately if
3655 // the child has already exited. */
3656 while (waitpid(pid, &status, 0) < 0) {
3657 switch (errno) {
3658 case ECHILD: return 0;
3659 case EINTR: break;
3660 default: return -1;
3661 }
3662 }
3663
3664 if (WIFEXITED(status)) {
3665 // The child exited normally; get its exit code.
3666 return WEXITSTATUS(status);
3667 } else if (WIFSIGNALED(status)) {
3668 // The child exited because of a signal
3669 // The best value to return is 0x80 + signal number,
3670 // because that is what all Unix shells do, and because
3671 // it allows callers to distinguish between process exit and
3672 // process death by signal.
3673 return 0x80 + WTERMSIG(status);
3674 } else {
3675 // Unknown exit code; pass it through
3676 return status;
3677 }
3678 }
3679 }
3680
3681 // Get the kern.corefile setting, or otherwise the default path to the core file
3682 // Returns the length of the string
3683 int os::get_core_path(char* buffer, size_t bufferSize) {
3684 int n = 0;
3685 #ifdef __APPLE__
3686 char coreinfo[MAX_PATH];
3687 size_t sz = sizeof(coreinfo);
3688 int ret = sysctlbyname("kern.corefile", coreinfo, &sz, NULL, 0);
3689 if (ret == 0) {
3690 char *pid_pos = strstr(coreinfo, "%P");
3691 // skip over the "%P" to preserve any optional custom user pattern
3692 const char* tail = (pid_pos != NULL) ? (pid_pos + 2) : "";
3693
3694 if (pid_pos != NULL) {
3695 *pid_pos = '\0';
3696 n = jio_snprintf(buffer, bufferSize, "%s%d%s", coreinfo, os::current_process_id(), tail);
3697 } else {
3698 n = jio_snprintf(buffer, bufferSize, "%s", coreinfo);
3699 }
3700 } else
3701 #endif
3702 {
3703 n = jio_snprintf(buffer, bufferSize, "/cores/core.%d", os::current_process_id());
3704 }
3705 // Truncate if theoretical string was longer than bufferSize
3706 n = MIN2(n, (int)bufferSize);
3707
3708 return n;
3709 }
3710
3711 bool os::supports_map_sync() {
3712 return false;
3713 }
3714
3715 #ifndef PRODUCT
3716 void TestReserveMemorySpecial_test() {
3717 // No tests available for this platform
3718 }
3719 #endif
3720
3721 bool os::start_debugging(char *buf, int buflen) {
3722 int len = (int)strlen(buf);
3723 char *p = &buf[len];
3724
3725 jio_snprintf(p, buflen-len,
3726 "\n\n"
3727 "Do you want to debug the problem?\n\n"
3728 "To debug, run 'gdb /proc/%d/exe %d'; then switch to thread " INTX_FORMAT " (" INTPTR_FORMAT ")\n"
3729 "Enter 'yes' to launch gdb automatically (PATH must include gdb)\n"
3730 "Otherwise, press RETURN to abort...",
3731 os::current_process_id(), os::current_process_id(),
3732 os::current_thread_id(), os::current_thread_id());
3733
3734 bool yes = os::message_box("Unexpected Error", buf);
3735
3736 if (yes) {
3737 // yes, user asked VM to launch debugger
3738 jio_snprintf(buf, sizeof(buf), "gdb /proc/%d/exe %d",
3739 os::current_process_id(), os::current_process_id());
3740
3741 os::fork_and_exec(buf);
3742 yes = false;
3743 }
3744 return yes;
3745 }