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
1555 #ifdef __APPLE__
1556 char osproductversion[100];
1557 size_t sz = sizeof(osproductversion);
1558 int ret = sysctlbyname("kern.osproductversion", osproductversion, &sz, NULL, 0);
1559 if (ret == 0) {
1560 char build[100];
1561 size = sizeof(build);
1562 int mib_build[] = { CTL_KERN, KERN_OSVERSION };
1563 if (sysctl(mib_build, 2, build, &size, NULL, 0) < 0) {
1564 snprintf(buf, buflen, "%s %s, macOS %s", os, release, osproductversion);
1565 } else {
1566 snprintf(buf, buflen, "%s %s, macOS %s (%s)", os, release, osproductversion, build);
1567 }
1568 } else
1569 #endif
1570 snprintf(buf, buflen, "%s %s", os, release);
1571 }
1572
1573 void os::print_os_info_brief(outputStream* st) {
1574 os::Posix::print_uname_info(st);
1575 }
1576
1577 void os::print_os_info(outputStream* st) {
1578 st->print("OS:");
1579
1580 os::Posix::print_uname_info(st);
1581
1582 os::Bsd::print_uptime_info(st);
1583
1584 os::Posix::print_rlimit_info(st);
1585
1586 os::Posix::print_load_average(st);
1587
1588 VM_Version::print_platform_virtualization_info(st);
1589 }
1590
1591 void os::pd_print_cpu_info(outputStream* st, char* buf, size_t buflen) {
1592 // Nothing to do for now.
1593 }
1594
1595 void os::get_summary_cpu_info(char* buf, size_t buflen) {
1596 unsigned int mhz;
1597 size_t size = sizeof(mhz);
1598 int mib[] = { CTL_HW, HW_CPU_FREQ };
1599 if (sysctl(mib, 2, &mhz, &size, NULL, 0) < 0) {
1600 mhz = 1; // looks like an error but can be divided by
1601 } else {
1602 mhz /= 1000000; // reported in millions
1603 }
1604
1605 char model[100];
1606 size = sizeof(model);
1607 int mib_model[] = { CTL_HW, HW_MODEL };
1608 if (sysctl(mib_model, 2, model, &size, NULL, 0) < 0) {
1609 strncpy(model, cpu_arch, sizeof(model));
1610 }
1611
1612 char machine[100];
1613 size = sizeof(machine);
1614 int mib_machine[] = { CTL_HW, HW_MACHINE };
1615 if (sysctl(mib_machine, 2, machine, &size, NULL, 0) < 0) {
1616 strncpy(machine, "", sizeof(machine));
1617 }
1618
1619 snprintf(buf, buflen, "%s %s %d MHz", model, machine, mhz);
1620 }
1621
1622 void os::print_memory_info(outputStream* st) {
1623 xsw_usage swap_usage;
1624 size_t size = sizeof(swap_usage);
1625
1626 st->print("Memory:");
1627 st->print(" %dk page", os::vm_page_size()>>10);
1628
1629 st->print(", physical " UINT64_FORMAT "k",
1630 os::physical_memory() >> 10);
1631 st->print("(" UINT64_FORMAT "k free)",
1632 os::available_memory() >> 10);
1633
1634 if((sysctlbyname("vm.swapusage", &swap_usage, &size, NULL, 0) == 0) || (errno == ENOMEM)) {
1635 if (size >= offset_of(xsw_usage, xsu_used)) {
1636 st->print(", swap " UINT64_FORMAT "k",
1637 ((julong) swap_usage.xsu_total) >> 10);
1638 st->print("(" UINT64_FORMAT "k free)",
1639 ((julong) swap_usage.xsu_avail) >> 10);
1640 }
1641 }
1642
1643 st->cr();
1644 }
1645
1646 static void print_signal_handler(outputStream* st, int sig,
1647 char* buf, size_t buflen);
1648
1649 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1650 st->print_cr("Signal Handlers:");
1651 print_signal_handler(st, SIGSEGV, buf, buflen);
1652 print_signal_handler(st, SIGBUS , buf, buflen);
1653 print_signal_handler(st, SIGFPE , buf, buflen);
1654 print_signal_handler(st, SIGPIPE, buf, buflen);
1655 print_signal_handler(st, SIGXFSZ, buf, buflen);
1656 print_signal_handler(st, SIGILL , buf, buflen);
1657 print_signal_handler(st, SR_signum, buf, buflen);
1658 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1659 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1660 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1661 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1662 }
1663
1664 static char saved_jvm_path[MAXPATHLEN] = {0};
1665
1666 // Find the full path to the current module, libjvm
1667 void os::jvm_path(char *buf, jint buflen) {
1668 // Error checking.
1669 if (buflen < MAXPATHLEN) {
1670 assert(false, "must use a large-enough buffer");
1671 buf[0] = '\0';
1672 return;
1673 }
1674 // Lazy resolve the path to current module.
1675 if (saved_jvm_path[0] != 0) {
1676 strcpy(buf, saved_jvm_path);
1677 return;
1678 }
1679
1680 char dli_fname[MAXPATHLEN];
1681 bool ret = dll_address_to_library_name(
1682 CAST_FROM_FN_PTR(address, os::jvm_path),
1683 dli_fname, sizeof(dli_fname), NULL);
1684 assert(ret, "cannot locate libjvm");
1685 char *rp = NULL;
1686 if (ret && dli_fname[0] != '\0') {
1687 rp = os::Posix::realpath(dli_fname, buf, buflen);
1688 }
1689 if (rp == NULL) {
1690 return;
1691 }
1692
1693 if (Arguments::sun_java_launcher_is_altjvm()) {
1694 // Support for the java launcher's '-XXaltjvm=<path>' option. Typical
1695 // value for buf is "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so"
1696 // or "<JAVA_HOME>/jre/lib/<vmtype>/libjvm.dylib". If "/jre/lib/"
1697 // appears at the right place in the string, then assume we are
1698 // installed in a JDK and we're done. Otherwise, check for a
1699 // JAVA_HOME environment variable and construct a path to the JVM
1700 // being overridden.
1701
1702 const char *p = buf + strlen(buf) - 1;
1703 for (int count = 0; p > buf && count < 5; ++count) {
1704 for (--p; p > buf && *p != '/'; --p)
1705 /* empty */ ;
1706 }
1707
1708 if (strncmp(p, "/jre/lib/", 9) != 0) {
1709 // Look for JAVA_HOME in the environment.
1710 char* java_home_var = ::getenv("JAVA_HOME");
1711 if (java_home_var != NULL && java_home_var[0] != 0) {
1712 char* jrelib_p;
1713 int len;
1714
1715 // Check the current module name "libjvm"
1716 p = strrchr(buf, '/');
1717 assert(strstr(p, "/libjvm") == p, "invalid library name");
1718
1719 rp = os::Posix::realpath(java_home_var, buf, buflen);
1720 if (rp == NULL) {
1721 return;
1722 }
1723
1724 // determine if this is a legacy image or modules image
1725 // modules image doesn't have "jre" subdirectory
1726 len = strlen(buf);
1727 assert(len < buflen, "Ran out of buffer space");
1728 jrelib_p = buf + len;
1729
1730 // Add the appropriate library subdir
1731 snprintf(jrelib_p, buflen-len, "/jre/lib");
1732 if (0 != access(buf, F_OK)) {
1733 snprintf(jrelib_p, buflen-len, "/lib");
1734 }
1735
1736 // Add the appropriate client or server subdir
1737 len = strlen(buf);
1738 jrelib_p = buf + len;
1739 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
1740 if (0 != access(buf, F_OK)) {
1741 snprintf(jrelib_p, buflen-len, "%s", "");
1742 }
1743
1744 // If the path exists within JAVA_HOME, add the JVM library name
1745 // to complete the path to JVM being overridden. Otherwise fallback
1746 // to the path to the current library.
1747 if (0 == access(buf, F_OK)) {
1748 // Use current module name "libjvm"
1749 len = strlen(buf);
1750 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
1751 } else {
1752 // Fall back to path of current library
1753 rp = os::Posix::realpath(dli_fname, buf, buflen);
1754 if (rp == NULL) {
1755 return;
1756 }
1757 }
1758 }
1759 }
1760 }
1761
1762 strncpy(saved_jvm_path, buf, MAXPATHLEN);
1763 saved_jvm_path[MAXPATHLEN - 1] = '\0';
1764 }
1765
1766 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1767 // no prefix required, not even "_"
1768 }
1769
1770 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1771 // no suffix required
1772 }
1773
1774 ////////////////////////////////////////////////////////////////////////////////
1775 // sun.misc.Signal support
1776
1777 static void UserHandler(int sig, void *siginfo, void *context) {
1778 // Ctrl-C is pressed during error reporting, likely because the error
1779 // handler fails to abort. Let VM die immediately.
1780 if (sig == SIGINT && VMError::is_error_reported()) {
1781 os::die();
1782 }
1783
1784 os::signal_notify(sig);
1785 }
1786
1787 void* os::user_handler() {
1788 return CAST_FROM_FN_PTR(void*, UserHandler);
1789 }
1790
1791 extern "C" {
1792 typedef void (*sa_handler_t)(int);
1793 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1794 }
1795
1796 void* os::signal(int signal_number, void* handler) {
1797 struct sigaction sigAct, oldSigAct;
1798
1799 sigfillset(&(sigAct.sa_mask));
1800 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
1801 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1802
1803 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1804 // -1 means registration failed
1805 return (void *)-1;
1806 }
1807
1808 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1809 }
1810
1811 void os::signal_raise(int signal_number) {
1812 ::raise(signal_number);
1813 }
1814
1815 // The following code is moved from os.cpp for making this
1816 // code platform specific, which it is by its very nature.
1817
1818 // Will be modified when max signal is changed to be dynamic
1819 int os::sigexitnum_pd() {
1820 return NSIG;
1821 }
1822
1823 // a counter for each possible signal value
1824 static volatile jint pending_signals[NSIG+1] = { 0 };
1825 static Semaphore* sig_sem = NULL;
1826
1827 static void jdk_misc_signal_init() {
1828 // Initialize signal structures
1829 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
1830
1831 // Initialize signal semaphore
1832 sig_sem = new Semaphore();
1833 }
1834
1835 void os::signal_notify(int sig) {
1836 if (sig_sem != NULL) {
1837 Atomic::inc(&pending_signals[sig]);
1838 sig_sem->signal();
1839 } else {
1840 // Signal thread is not created with ReduceSignalUsage and jdk_misc_signal_init
1841 // initialization isn't called.
1842 assert(ReduceSignalUsage, "signal semaphore should be created");
1843 }
1844 }
1845
1846 static int check_pending_signals() {
1847 for (;;) {
1848 for (int i = 0; i < NSIG + 1; i++) {
1849 jint n = pending_signals[i];
1850 if (n > 0 && n == Atomic::cmpxchg(&pending_signals[i], n, n - 1)) {
1851 return i;
1852 }
1853 }
1854 JavaThread *thread = JavaThread::current();
1855 ThreadBlockInVM tbivm(thread);
1856
1857 bool threadIsSuspended;
1858 do {
1859 thread->set_suspend_equivalent();
1860 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
1861 sig_sem->wait();
1862
1863 // were we externally suspended while we were waiting?
1864 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
1865 if (threadIsSuspended) {
1866 // The semaphore has been incremented, but while we were waiting
1867 // another thread suspended us. We don't want to continue running
1868 // while suspended because that would surprise the thread that
1869 // suspended us.
1870 sig_sem->signal();
1871
1872 thread->java_suspend_self();
1873 }
1874 } while (threadIsSuspended);
1875 }
1876 }
1877
1878 int os::signal_wait() {
1879 return check_pending_signals();
1880 }
1881
1882 ////////////////////////////////////////////////////////////////////////////////
1883 // Virtual Memory
1884
1885 int os::vm_page_size() {
1886 // Seems redundant as all get out
1887 assert(os::Bsd::page_size() != -1, "must call os::init");
1888 return os::Bsd::page_size();
1889 }
1890
1891 // Solaris allocates memory by pages.
1892 int os::vm_allocation_granularity() {
1893 assert(os::Bsd::page_size() != -1, "must call os::init");
1894 return os::Bsd::page_size();
1895 }
1896
1897 static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
1898 int err) {
1899 warning("INFO: os::commit_memory(" INTPTR_FORMAT ", " SIZE_FORMAT
1900 ", %d) failed; error='%s' (errno=%d)", (intptr_t)addr, size, exec,
1901 os::errno_name(err), err);
1902 }
1903
1904 // NOTE: Bsd kernel does not really reserve the pages for us.
1905 // All it does is to check if there are enough free pages
1906 // left at the time of mmap(). This could be a potential
1907 // problem.
1908 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
1909 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
1910 #ifdef __OpenBSD__
1911 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
1912 Events::log(NULL, "Protecting memory [" INTPTR_FORMAT "," INTPTR_FORMAT "] with protection modes %x", p2i(addr), p2i(addr+size), prot);
1913 if (::mprotect(addr, size, prot) == 0) {
1914 return true;
1915 }
1916 #else
1917 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
1918 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
1919 if (res != (uintptr_t) MAP_FAILED) {
1920 return true;
1921 }
1922 #endif
1923
1924 // Warn about any commit errors we see in non-product builds just
1925 // in case mmap() doesn't work as described on the man page.
1926 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);)
1927
1928 return false;
1929 }
1930
1931 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
1932 bool exec) {
1933 // alignment_hint is ignored on this OS
1934 return pd_commit_memory(addr, size, exec);
1935 }
1936
1937 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
1938 const char* mesg) {
1939 assert(mesg != NULL, "mesg must be specified");
1940 if (!pd_commit_memory(addr, size, exec)) {
1941 // add extra info in product mode for vm_exit_out_of_memory():
1942 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
1943 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, "%s", mesg);
1944 }
1945 }
1946
1947 void os::pd_commit_memory_or_exit(char* addr, size_t size,
1948 size_t alignment_hint, bool exec,
1949 const char* mesg) {
1950 // alignment_hint is ignored on this OS
1951 pd_commit_memory_or_exit(addr, size, exec, mesg);
1952 }
1953
1954 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
1955 }
1956
1957 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
1958 ::madvise(addr, bytes, MADV_DONTNEED);
1959 }
1960
1961 void os::numa_make_global(char *addr, size_t bytes) {
1962 }
1963
1964 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
1965 }
1966
1967 bool os::numa_topology_changed() { return false; }
1968
1969 size_t os::numa_get_groups_num() {
1970 return 1;
1971 }
1972
1973 int os::numa_get_group_id() {
1974 return 0;
1975 }
1976
1977 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
1978 if (size > 0) {
1979 ids[0] = 0;
1980 return 1;
1981 }
1982 return 0;
1983 }
1984
1985 int os::numa_get_group_id_for_address(const void* address) {
1986 return 0;
1987 }
1988
1989 bool os::get_page_info(char *start, page_info* info) {
1990 return false;
1991 }
1992
1993 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
1994 return end;
1995 }
1996
1997
1998 bool os::pd_uncommit_memory(char* addr, size_t size) {
1999 #ifdef __OpenBSD__
2000 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2001 Events::log(NULL, "Protecting memory [" INTPTR_FORMAT "," INTPTR_FORMAT "] with PROT_NONE", p2i(addr), p2i(addr+size));
2002 return ::mprotect(addr, size, PROT_NONE) == 0;
2003 #else
2004 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
2005 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
2006 return res != (uintptr_t) MAP_FAILED;
2007 #endif
2008 }
2009
2010 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2011 return os::commit_memory(addr, size, !ExecMem);
2012 }
2013
2014 // If this is a growable mapping, remove the guard pages entirely by
2015 // munmap()ping them. If not, just call uncommit_memory().
2016 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2017 return os::uncommit_memory(addr, size);
2018 }
2019
2020 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2021 // at 'requested_addr'. If there are existing memory mappings at the same
2022 // location, however, they will be overwritten. If 'fixed' is false,
2023 // 'requested_addr' is only treated as a hint, the return value may or
2024 // may not start from the requested address. Unlike Bsd mmap(), this
2025 // function returns NULL to indicate failure.
2026 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2027 char * addr;
2028 int flags;
2029
2030 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2031 if (fixed) {
2032 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2033 flags |= MAP_FIXED;
2034 }
2035
2036 // Map reserved/uncommitted pages PROT_NONE so we fail early if we
2037 // touch an uncommitted page. Otherwise, the read/write might
2038 // succeed if we have enough swap space to back the physical page.
2039 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE,
2040 flags, -1, 0);
2041
2042 return addr == MAP_FAILED ? NULL : addr;
2043 }
2044
2045 static int anon_munmap(char * addr, size_t size) {
2046 return ::munmap(addr, size) == 0;
2047 }
2048
2049 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
2050 size_t alignment_hint) {
2051 return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2052 }
2053
2054 bool os::pd_release_memory(char* addr, size_t size) {
2055 return anon_munmap(addr, size);
2056 }
2057
2058 static bool bsd_mprotect(char* addr, size_t size, int prot) {
2059 // Bsd wants the mprotect address argument to be page aligned.
2060 char* bottom = (char*)align_down((intptr_t)addr, os::Bsd::page_size());
2061
2062 // According to SUSv3, mprotect() should only be used with mappings
2063 // established by mmap(), and mmap() always maps whole pages. Unaligned
2064 // 'addr' likely indicates problem in the VM (e.g. trying to change
2065 // protection of malloc'ed or statically allocated memory). Check the
2066 // caller if you hit this assert.
2067 assert(addr == bottom, "sanity check");
2068
2069 size = align_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2070 Events::log(NULL, "Protecting memory [" INTPTR_FORMAT "," INTPTR_FORMAT "] with protection modes %x", p2i(bottom), p2i(bottom+size), prot);
2071 return ::mprotect(bottom, size, prot) == 0;
2072 }
2073
2074 // Set protections specified
2075 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2076 bool is_committed) {
2077 unsigned int p = 0;
2078 switch (prot) {
2079 case MEM_PROT_NONE: p = PROT_NONE; break;
2080 case MEM_PROT_READ: p = PROT_READ; break;
2081 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
2082 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2083 default:
2084 ShouldNotReachHere();
2085 }
2086 // is_committed is unused.
2087 return bsd_mprotect(addr, bytes, p);
2088 }
2089
2090 bool os::guard_memory(char* addr, size_t size) {
2091 return bsd_mprotect(addr, size, PROT_NONE);
2092 }
2093
2094 bool os::unguard_memory(char* addr, size_t size) {
2095 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
2096 }
2097
2098 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
2099 return false;
2100 }
2101
2102 // Large page support
2103
2104 static size_t _large_page_size = 0;
2105
2106 void os::large_page_init() {
2107 }
2108
2109
2110 char* os::pd_reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) {
2111 fatal("os::reserve_memory_special should not be called on BSD.");
2112 return NULL;
2113 }
2114
2115 bool os::pd_release_memory_special(char* base, size_t bytes) {
2116 fatal("os::release_memory_special should not be called on BSD.");
2117 return false;
2118 }
2119
2120 size_t os::large_page_size() {
2121 return _large_page_size;
2122 }
2123
2124 bool os::can_commit_large_page_memory() {
2125 // Does not matter, we do not support huge pages.
2126 return false;
2127 }
2128
2129 bool os::can_execute_large_page_memory() {
2130 // Does not matter, we do not support huge pages.
2131 return false;
2132 }
2133
2134 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr, int file_desc) {
2135 assert(file_desc >= 0, "file_desc is not valid");
2136 char* result = pd_attempt_reserve_memory_at(bytes, requested_addr);
2137 if (result != NULL) {
2138 if (replace_existing_mapping_with_file_mapping(result, bytes, file_desc) == NULL) {
2139 vm_exit_during_initialization(err_msg("Error in mapping Java heap at the given filesystem directory"));
2140 }
2141 }
2142 return result;
2143 }
2144
2145 // Reserve memory at an arbitrary address, only if that area is
2146 // available (and not reserved for something else).
2147
2148 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2149 // Assert only that the size is a multiple of the page size, since
2150 // that's all that mmap requires, and since that's all we really know
2151 // about at this low abstraction level. If we need higher alignment,
2152 // we can either pass an alignment to this method or verify alignment
2153 // in one of the methods further up the call chain. See bug 5044738.
2154 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2155
2156 // Repeatedly allocate blocks until the block is allocated at the
2157 // right spot.
2158
2159 // Bsd mmap allows caller to pass an address as hint; give it a try first,
2160 // if kernel honors the hint then we can return immediately.
2161 char * addr = anon_mmap(requested_addr, bytes, false);
2162 if (addr == requested_addr) {
2163 return requested_addr;
2164 }
2165
2166 if (addr != NULL) {
2167 // mmap() is successful but it fails to reserve at the requested address
2168 anon_munmap(addr, bytes);
2169 }
2170
2171 return NULL;
2172 }
2173
2174 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2175 void os::infinite_sleep() {
2176 while (true) { // sleep forever ...
2177 ::sleep(100); // ... 100 seconds at a time
2178 }
2179 }
2180
2181 // Used to convert frequent JVM_Yield() to nops
2182 bool os::dont_yield() {
2183 return DontYieldALot;
2184 }
2185
2186 void os::naked_yield() {
2187 sched_yield();
2188 }
2189
2190 ////////////////////////////////////////////////////////////////////////////////
2191 // thread priority support
2192
2193 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2194 // only supports dynamic priority, static priority must be zero. For real-time
2195 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
2196 // However, for large multi-threaded applications, SCHED_RR is not only slower
2197 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2198 // of 5 runs - Sep 2005).
2199 //
2200 // The following code actually changes the niceness of kernel-thread/LWP. It
2201 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
2202 // not the entire user process, and user level threads are 1:1 mapped to kernel
2203 // threads. It has always been the case, but could change in the future. For
2204 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2205 // It is only used when ThreadPriorityPolicy=1 and may require system level permission
2206 // (e.g., root privilege or CAP_SYS_NICE capability).
2207
2208 #if !defined(__APPLE__)
2209 int os::java_to_os_priority[CriticalPriority + 1] = {
2210 19, // 0 Entry should never be used
2211
2212 0, // 1 MinPriority
2213 3, // 2
2214 6, // 3
2215
2216 10, // 4
2217 15, // 5 NormPriority
2218 18, // 6
2219
2220 21, // 7
2221 25, // 8
2222 28, // 9 NearMaxPriority
2223
2224 31, // 10 MaxPriority
2225
2226 31 // 11 CriticalPriority
2227 };
2228 #else
2229 // Using Mach high-level priority assignments
2230 int os::java_to_os_priority[CriticalPriority + 1] = {
2231 0, // 0 Entry should never be used (MINPRI_USER)
2232
2233 27, // 1 MinPriority
2234 28, // 2
2235 29, // 3
2236
2237 30, // 4
2238 31, // 5 NormPriority (BASEPRI_DEFAULT)
2239 32, // 6
2240
2241 33, // 7
2242 34, // 8
2243 35, // 9 NearMaxPriority
2244
2245 36, // 10 MaxPriority
2246
2247 36 // 11 CriticalPriority
2248 };
2249 #endif
2250
2251 static int prio_init() {
2252 if (ThreadPriorityPolicy == 1) {
2253 if (geteuid() != 0) {
2254 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy) && !FLAG_IS_JIMAGE_RESOURCE(ThreadPriorityPolicy)) {
2255 warning("-XX:ThreadPriorityPolicy=1 may require system level permission, " \
2256 "e.g., being the root user. If the necessary permission is not " \
2257 "possessed, changes to priority will be silently ignored.");
2258 }
2259 }
2260 }
2261 if (UseCriticalJavaThreadPriority) {
2262 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2263 }
2264 return 0;
2265 }
2266
2267 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2268 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) return OS_OK;
2269
2270 #ifdef __OpenBSD__
2271 // OpenBSD pthread_setprio starves low priority threads
2272 return OS_OK;
2273 #elif defined(__FreeBSD__)
2274 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2275 return (ret == 0) ? OS_OK : OS_ERR;
2276 #elif defined(__APPLE__) || defined(__NetBSD__)
2277 struct sched_param sp;
2278 int policy;
2279
2280 if (pthread_getschedparam(thread->osthread()->pthread_id(), &policy, &sp) != 0) {
2281 return OS_ERR;
2282 }
2283
2284 sp.sched_priority = newpri;
2285 if (pthread_setschedparam(thread->osthread()->pthread_id(), policy, &sp) != 0) {
2286 return OS_ERR;
2287 }
2288
2289 return OS_OK;
2290 #else
2291 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2292 return (ret == 0) ? OS_OK : OS_ERR;
2293 #endif
2294 }
2295
2296 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2297 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) {
2298 *priority_ptr = java_to_os_priority[NormPriority];
2299 return OS_OK;
2300 }
2301
2302 errno = 0;
2303 #if defined(__OpenBSD__) || defined(__FreeBSD__)
2304 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2305 #elif defined(__APPLE__) || defined(__NetBSD__)
2306 int policy;
2307 struct sched_param sp;
2308
2309 int res = pthread_getschedparam(thread->osthread()->pthread_id(), &policy, &sp);
2310 if (res != 0) {
2311 *priority_ptr = -1;
2312 return OS_ERR;
2313 } else {
2314 *priority_ptr = sp.sched_priority;
2315 return OS_OK;
2316 }
2317 #else
2318 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2319 #endif
2320 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2321 }
2322
2323 ////////////////////////////////////////////////////////////////////////////////
2324 // suspend/resume support
2325
2326 // The low-level signal-based suspend/resume support is a remnant from the
2327 // old VM-suspension that used to be for java-suspension, safepoints etc,
2328 // within hotspot. Currently used by JFR's OSThreadSampler
2329 //
2330 // The remaining code is greatly simplified from the more general suspension
2331 // code that used to be used.
2332 //
2333 // The protocol is quite simple:
2334 // - suspend:
2335 // - sends a signal to the target thread
2336 // - polls the suspend state of the osthread using a yield loop
2337 // - target thread signal handler (SR_handler) sets suspend state
2338 // and blocks in sigsuspend until continued
2339 // - resume:
2340 // - sets target osthread state to continue
2341 // - sends signal to end the sigsuspend loop in the SR_handler
2342 //
2343 // Note that the SR_lock plays no role in this suspend/resume protocol,
2344 // but is checked for NULL in SR_handler as a thread termination indicator.
2345 // The SR_lock is, however, used by JavaThread::java_suspend()/java_resume() APIs.
2346 //
2347 // Note that resume_clear_context() and suspend_save_context() are needed
2348 // by SR_handler(), so that fetch_frame_from_context() works,
2349 // which in part is used by:
2350 // - Forte Analyzer: AsyncGetCallTrace()
2351 // - StackBanging: get_frame_at_stack_banging_point()
2352
2353 static void resume_clear_context(OSThread *osthread) {
2354 osthread->set_ucontext(NULL);
2355 osthread->set_siginfo(NULL);
2356 }
2357
2358 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2359 osthread->set_ucontext(context);
2360 osthread->set_siginfo(siginfo);
2361 }
2362
2363 // Handler function invoked when a thread's execution is suspended or
2364 // resumed. We have to be careful that only async-safe functions are
2365 // called here (Note: most pthread functions are not async safe and
2366 // should be avoided.)
2367 //
2368 // Note: sigwait() is a more natural fit than sigsuspend() from an
2369 // interface point of view, but sigwait() prevents the signal hander
2370 // from being run. libpthread would get very confused by not having
2371 // its signal handlers run and prevents sigwait()'s use with the
2372 // mutex granting granting signal.
2373 //
2374 // Currently only ever called on the VMThread or JavaThread
2375 //
2376 #ifdef __APPLE__
2377 static OSXSemaphore sr_semaphore;
2378 #else
2379 static PosixSemaphore sr_semaphore;
2380 #endif
2381
2382 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2383 // Save and restore errno to avoid confusing native code with EINTR
2384 // after sigsuspend.
2385 int old_errno = errno;
2386
2387 Thread* thread = Thread::current_or_null_safe();
2388 assert(thread != NULL, "Missing current thread in SR_handler");
2389
2390 // On some systems we have seen signal delivery get "stuck" until the signal
2391 // mask is changed as part of thread termination. Check that the current thread
2392 // has not already terminated (via SR_lock()) - else the following assertion
2393 // will fail because the thread is no longer a JavaThread as the ~JavaThread
2394 // destructor has completed.
2395
2396 if (thread->SR_lock() == NULL) {
2397 return;
2398 }
2399
2400 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
2401
2402 OSThread* osthread = thread->osthread();
2403
2404 os::SuspendResume::State current = osthread->sr.state();
2405 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
2406 suspend_save_context(osthread, siginfo, context);
2407
2408 // attempt to switch the state, we assume we had a SUSPEND_REQUEST
2409 os::SuspendResume::State state = osthread->sr.suspended();
2410 if (state == os::SuspendResume::SR_SUSPENDED) {
2411 sigset_t suspend_set; // signals for sigsuspend()
2412
2413 // get current set of blocked signals and unblock resume signal
2414 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2415 sigdelset(&suspend_set, SR_signum);
2416
2417 sr_semaphore.signal();
2418 // wait here until we are resumed
2419 while (1) {
2420 sigsuspend(&suspend_set);
2421
2422 os::SuspendResume::State result = osthread->sr.running();
2423 if (result == os::SuspendResume::SR_RUNNING) {
2424 sr_semaphore.signal();
2425 break;
2426 } else if (result != os::SuspendResume::SR_SUSPENDED) {
2427 ShouldNotReachHere();
2428 }
2429 }
2430
2431 } else if (state == os::SuspendResume::SR_RUNNING) {
2432 // request was cancelled, continue
2433 } else {
2434 ShouldNotReachHere();
2435 }
2436
2437 resume_clear_context(osthread);
2438 } else if (current == os::SuspendResume::SR_RUNNING) {
2439 // request was cancelled, continue
2440 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
2441 // ignore
2442 } else {
2443 // ignore
2444 }
2445
2446 errno = old_errno;
2447 }
2448
2449
2450 static int SR_initialize() {
2451 struct sigaction act;
2452 char *s;
2453 // Get signal number to use for suspend/resume
2454 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2455 int sig = ::strtol(s, 0, 10);
2456 if (sig > MAX2(SIGSEGV, SIGBUS) && // See 4355769.
2457 sig < NSIG) { // Must be legal signal and fit into sigflags[].
2458 SR_signum = sig;
2459 } else {
2460 warning("You set _JAVA_SR_SIGNUM=%d. It must be in range [%d, %d]. Using %d instead.",
2461 sig, MAX2(SIGSEGV, SIGBUS)+1, NSIG-1, SR_signum);
2462 }
2463 }
2464
2465 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2466 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2467
2468 sigemptyset(&SR_sigset);
2469 sigaddset(&SR_sigset, SR_signum);
2470
2471 // Set up signal handler for suspend/resume
2472 act.sa_flags = SA_RESTART|SA_SIGINFO;
2473 act.sa_handler = (void (*)(int)) SR_handler;
2474
2475 // SR_signum is blocked by default.
2476 // 4528190 - We also need to block pthread restart signal (32 on all
2477 // supported Bsd platforms). Note that BsdThreads need to block
2478 // this signal for all threads to work properly. So we don't have
2479 // to use hard-coded signal number when setting up the mask.
2480 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2481
2482 if (sigaction(SR_signum, &act, 0) == -1) {
2483 return -1;
2484 }
2485
2486 // Save signal flag
2487 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2488 return 0;
2489 }
2490
2491 static int sr_notify(OSThread* osthread) {
2492 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2493 assert_status(status == 0, status, "pthread_kill");
2494 return status;
2495 }
2496
2497 // "Randomly" selected value for how long we want to spin
2498 // before bailing out on suspending a thread, also how often
2499 // we send a signal to a thread we want to resume
2500 static const int RANDOMLY_LARGE_INTEGER = 1000000;
2501 static const int RANDOMLY_LARGE_INTEGER2 = 100;
2502
2503 // returns true on success and false on error - really an error is fatal
2504 // but this seems the normal response to library errors
2505 static bool do_suspend(OSThread* osthread) {
2506 assert(osthread->sr.is_running(), "thread should be running");
2507 assert(!sr_semaphore.trywait(), "semaphore has invalid state");
2508
2509 // mark as suspended and send signal
2510 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
2511 // failed to switch, state wasn't running?
2512 ShouldNotReachHere();
2513 return false;
2514 }
2515
2516 if (sr_notify(osthread) != 0) {
2517 ShouldNotReachHere();
2518 }
2519
2520 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
2521 while (true) {
2522 if (sr_semaphore.timedwait(2)) {
2523 break;
2524 } else {
2525 // timeout
2526 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
2527 if (cancelled == os::SuspendResume::SR_RUNNING) {
2528 return false;
2529 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
2530 // make sure that we consume the signal on the semaphore as well
2531 sr_semaphore.wait();
2532 break;
2533 } else {
2534 ShouldNotReachHere();
2535 return false;
2536 }
2537 }
2538 }
2539
2540 guarantee(osthread->sr.is_suspended(), "Must be suspended");
2541 return true;
2542 }
2543
2544 static void do_resume(OSThread* osthread) {
2545 assert(osthread->sr.is_suspended(), "thread should be suspended");
2546 assert(!sr_semaphore.trywait(), "invalid semaphore state");
2547
2548 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
2549 // failed to switch to WAKEUP_REQUEST
2550 ShouldNotReachHere();
2551 return;
2552 }
2553
2554 while (true) {
2555 if (sr_notify(osthread) == 0) {
2556 if (sr_semaphore.timedwait(2)) {
2557 if (osthread->sr.is_running()) {
2558 return;
2559 }
2560 }
2561 } else {
2562 ShouldNotReachHere();
2563 }
2564 }
2565
2566 guarantee(osthread->sr.is_running(), "Must be running!");
2567 }
2568
2569 ///////////////////////////////////////////////////////////////////////////////////
2570 // signal handling (except suspend/resume)
2571
2572 // This routine may be used by user applications as a "hook" to catch signals.
2573 // The user-defined signal handler must pass unrecognized signals to this
2574 // routine, and if it returns true (non-zero), then the signal handler must
2575 // return immediately. If the flag "abort_if_unrecognized" is true, then this
2576 // routine will never retun false (zero), but instead will execute a VM panic
2577 // routine kill the process.
2578 //
2579 // If this routine returns false, it is OK to call it again. This allows
2580 // the user-defined signal handler to perform checks either before or after
2581 // the VM performs its own checks. Naturally, the user code would be making
2582 // a serious error if it tried to handle an exception (such as a null check
2583 // or breakpoint) that the VM was generating for its own correct operation.
2584 //
2585 // This routine may recognize any of the following kinds of signals:
2586 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
2587 // It should be consulted by handlers for any of those signals.
2588 //
2589 // The caller of this routine must pass in the three arguments supplied
2590 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
2591 // field of the structure passed to sigaction(). This routine assumes that
2592 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
2593 //
2594 // Note that the VM will print warnings if it detects conflicting signal
2595 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
2596 //
2597 extern "C" JNIEXPORT int JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
2598 void* ucontext,
2599 int abort_if_unrecognized);
2600
2601 static void signalHandler(int sig, siginfo_t* info, void* uc) {
2602 assert(info != NULL && uc != NULL, "it must be old kernel");
2603 int orig_errno = errno; // Preserve errno value over signal handler.
2604 JVM_handle_bsd_signal(sig, info, uc, true);
2605 errno = orig_errno;
2606 }
2607
2608
2609 // This boolean allows users to forward their own non-matching signals
2610 // to JVM_handle_bsd_signal, harmlessly.
2611 bool os::Bsd::signal_handlers_are_installed = false;
2612
2613 // For signal-chaining
2614 bool os::Bsd::libjsig_is_loaded = false;
2615 typedef struct sigaction *(*get_signal_t)(int);
2616 get_signal_t os::Bsd::get_signal_action = NULL;
2617
2618 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
2619 struct sigaction *actp = NULL;
2620
2621 if (libjsig_is_loaded) {
2622 // Retrieve the old signal handler from libjsig
2623 actp = (*get_signal_action)(sig);
2624 }
2625 if (actp == NULL) {
2626 // Retrieve the preinstalled signal handler from jvm
2627 actp = os::Posix::get_preinstalled_handler(sig);
2628 }
2629
2630 return actp;
2631 }
2632
2633 static bool call_chained_handler(struct sigaction *actp, int sig,
2634 siginfo_t *siginfo, void *context) {
2635 // Call the old signal handler
2636 if (actp->sa_handler == SIG_DFL) {
2637 // It's more reasonable to let jvm treat it as an unexpected exception
2638 // instead of taking the default action.
2639 return false;
2640 } else if (actp->sa_handler != SIG_IGN) {
2641 if ((actp->sa_flags & SA_NODEFER) == 0) {
2642 // automaticlly block the signal
2643 sigaddset(&(actp->sa_mask), sig);
2644 }
2645
2646 sa_handler_t hand;
2647 sa_sigaction_t sa;
2648 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
2649 // retrieve the chained handler
2650 if (siginfo_flag_set) {
2651 sa = actp->sa_sigaction;
2652 } else {
2653 hand = actp->sa_handler;
2654 }
2655
2656 if ((actp->sa_flags & SA_RESETHAND) != 0) {
2657 actp->sa_handler = SIG_DFL;
2658 }
2659
2660 // try to honor the signal mask
2661 sigset_t oset;
2662 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
2663
2664 // call into the chained handler
2665 if (siginfo_flag_set) {
2666 (*sa)(sig, siginfo, context);
2667 } else {
2668 (*hand)(sig);
2669 }
2670
2671 // restore the signal mask
2672 pthread_sigmask(SIG_SETMASK, &oset, 0);
2673 }
2674 // Tell jvm's signal handler the signal is taken care of.
2675 return true;
2676 }
2677
2678 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
2679 bool chained = false;
2680 // signal-chaining
2681 if (UseSignalChaining) {
2682 struct sigaction *actp = get_chained_signal_action(sig);
2683 if (actp != NULL) {
2684 chained = call_chained_handler(actp, sig, siginfo, context);
2685 }
2686 }
2687 return chained;
2688 }
2689
2690 // for diagnostic
2691 int sigflags[NSIG];
2692
2693 int os::Bsd::get_our_sigflags(int sig) {
2694 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
2695 return sigflags[sig];
2696 }
2697
2698 void os::Bsd::set_our_sigflags(int sig, int flags) {
2699 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
2700 if (sig > 0 && sig < NSIG) {
2701 sigflags[sig] = flags;
2702 }
2703 }
2704
2705 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
2706 // Check for overwrite.
2707 struct sigaction oldAct;
2708 sigaction(sig, (struct sigaction*)NULL, &oldAct);
2709
2710 void* oldhand = oldAct.sa_sigaction
2711 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
2712 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
2713 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
2714 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
2715 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
2716 if (AllowUserSignalHandlers || !set_installed) {
2717 // Do not overwrite; user takes responsibility to forward to us.
2718 return;
2719 } else if (UseSignalChaining) {
2720 // save the old handler in jvm
2721 os::Posix::save_preinstalled_handler(sig, oldAct);
2722 // libjsig also interposes the sigaction() call below and saves the
2723 // old sigaction on it own.
2724 } else {
2725 fatal("Encountered unexpected pre-existing sigaction handler "
2726 "%#lx for signal %d.", (long)oldhand, sig);
2727 }
2728 }
2729
2730 struct sigaction sigAct;
2731 sigfillset(&(sigAct.sa_mask));
2732 sigAct.sa_handler = SIG_DFL;
2733 if (!set_installed) {
2734 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
2735 } else {
2736 sigAct.sa_sigaction = signalHandler;
2737 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
2738 }
2739 #ifdef __APPLE__
2740 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV
2741 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages"
2742 // if the signal handler declares it will handle it on alternate stack.
2743 // Notice we only declare we will handle it on alt stack, but we are not
2744 // actually going to use real alt stack - this is just a workaround.
2745 // Please see ux_exception.c, method catch_mach_exception_raise for details
2746 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c
2747 if (sig == SIGSEGV) {
2748 sigAct.sa_flags |= SA_ONSTACK;
2749 }
2750 #endif
2751
2752 // Save flags, which are set by ours
2753 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
2754 sigflags[sig] = sigAct.sa_flags;
2755
2756 int ret = sigaction(sig, &sigAct, &oldAct);
2757 assert(ret == 0, "check");
2758
2759 void* oldhand2 = oldAct.sa_sigaction
2760 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
2761 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
2762 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
2763 }
2764
2765 // install signal handlers for signals that HotSpot needs to
2766 // handle in order to support Java-level exception handling.
2767
2768 void os::Bsd::install_signal_handlers() {
2769 if (!signal_handlers_are_installed) {
2770 signal_handlers_are_installed = true;
2771
2772 // signal-chaining
2773 typedef void (*signal_setting_t)();
2774 signal_setting_t begin_signal_setting = NULL;
2775 signal_setting_t end_signal_setting = NULL;
2776 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
2777 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
2778 if (begin_signal_setting != NULL) {
2779 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
2780 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
2781 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
2782 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
2783 libjsig_is_loaded = true;
2784 assert(UseSignalChaining, "should enable signal-chaining");
2785 }
2786 if (libjsig_is_loaded) {
2787 // Tell libjsig jvm is setting signal handlers
2788 (*begin_signal_setting)();
2789 }
2790
2791 set_signal_handler(SIGSEGV, true);
2792 set_signal_handler(SIGPIPE, true);
2793 set_signal_handler(SIGBUS, true);
2794 set_signal_handler(SIGILL, true);
2795 set_signal_handler(SIGFPE, true);
2796 set_signal_handler(SIGXFSZ, true);
2797
2798 #if defined(__APPLE__)
2799 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
2800 // signals caught and handled by the JVM. To work around this, we reset the mach task
2801 // signal handler that's placed on our process by CrashReporter. This disables
2802 // CrashReporter-based reporting.
2803 //
2804 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
2805 // on caught fatal signals.
2806 //
2807 // Additionally, gdb installs both standard BSD signal handlers, and mach exception
2808 // handlers. By replacing the existing task exception handler, we disable gdb's mach
2809 // exception handling, while leaving the standard BSD signal handlers functional.
2810 kern_return_t kr;
2811 kr = task_set_exception_ports(mach_task_self(),
2812 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
2813 MACH_PORT_NULL,
2814 EXCEPTION_STATE_IDENTITY,
2815 MACHINE_THREAD_STATE);
2816
2817 assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
2818 #endif
2819
2820 if (libjsig_is_loaded) {
2821 // Tell libjsig jvm finishes setting signal handlers
2822 (*end_signal_setting)();
2823 }
2824
2825 // We don't activate signal checker if libjsig is in place, we trust ourselves
2826 // and if UserSignalHandler is installed all bets are off
2827 if (CheckJNICalls) {
2828 if (libjsig_is_loaded) {
2829 log_debug(jni, resolve)("Info: libjsig is activated, all active signal checking is disabled");
2830 check_signals = false;
2831 }
2832 if (AllowUserSignalHandlers) {
2833 log_debug(jni, resolve)("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
2834 check_signals = false;
2835 }
2836 }
2837 }
2838 }
2839
2840
2841 /////
2842 // glibc on Bsd platform uses non-documented flag
2843 // to indicate, that some special sort of signal
2844 // trampoline is used.
2845 // We will never set this flag, and we should
2846 // ignore this flag in our diagnostic
2847 #ifdef SIGNIFICANT_SIGNAL_MASK
2848 #undef SIGNIFICANT_SIGNAL_MASK
2849 #endif
2850 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
2851
2852 static const char* get_signal_handler_name(address handler,
2853 char* buf, int buflen) {
2854 int offset;
2855 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
2856 if (found) {
2857 // skip directory names
2858 const char *p1, *p2;
2859 p1 = buf;
2860 size_t len = strlen(os::file_separator());
2861 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
2862 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
2863 } else {
2864 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
2865 }
2866 return buf;
2867 }
2868
2869 static void print_signal_handler(outputStream* st, int sig,
2870 char* buf, size_t buflen) {
2871 struct sigaction sa;
2872
2873 sigaction(sig, NULL, &sa);
2874
2875 // See comment for SIGNIFICANT_SIGNAL_MASK define
2876 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
2877
2878 st->print("%s: ", os::exception_name(sig, buf, buflen));
2879
2880 address handler = (sa.sa_flags & SA_SIGINFO)
2881 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
2882 : CAST_FROM_FN_PTR(address, sa.sa_handler);
2883
2884 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
2885 st->print("SIG_DFL");
2886 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
2887 st->print("SIG_IGN");
2888 } else {
2889 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
2890 }
2891
2892 st->print(", sa_mask[0]=");
2893 os::Posix::print_signal_set_short(st, &sa.sa_mask);
2894
2895 address rh = VMError::get_resetted_sighandler(sig);
2896 // May be, handler was resetted by VMError?
2897 if (rh != NULL) {
2898 handler = rh;
2899 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
2900 }
2901
2902 st->print(", sa_flags=");
2903 os::Posix::print_sa_flags(st, sa.sa_flags);
2904
2905 // Check: is it our handler?
2906 if (handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
2907 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
2908 // It is our signal handler
2909 // check for flags, reset system-used one!
2910 if ((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
2911 st->print(
2912 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
2913 os::Bsd::get_our_sigflags(sig));
2914 }
2915 }
2916 st->cr();
2917 }
2918
2919
2920 #define DO_SIGNAL_CHECK(sig) \
2921 do { \
2922 if (!sigismember(&check_signal_done, sig)) { \
2923 os::Bsd::check_signal_handler(sig); \
2924 } \
2925 } while (0)
2926
2927 // This method is a periodic task to check for misbehaving JNI applications
2928 // under CheckJNI, we can add any periodic checks here
2929
2930 void os::run_periodic_checks() {
2931
2932 if (check_signals == false) return;
2933
2934 // SEGV and BUS if overridden could potentially prevent
2935 // generation of hs*.log in the event of a crash, debugging
2936 // such a case can be very challenging, so we absolutely
2937 // check the following for a good measure:
2938 DO_SIGNAL_CHECK(SIGSEGV);
2939 DO_SIGNAL_CHECK(SIGILL);
2940 DO_SIGNAL_CHECK(SIGFPE);
2941 DO_SIGNAL_CHECK(SIGBUS);
2942 DO_SIGNAL_CHECK(SIGPIPE);
2943 DO_SIGNAL_CHECK(SIGXFSZ);
2944
2945
2946 // ReduceSignalUsage allows the user to override these handlers
2947 // see comments at the very top and jvm_md.h
2948 if (!ReduceSignalUsage) {
2949 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
2950 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
2951 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
2952 DO_SIGNAL_CHECK(BREAK_SIGNAL);
2953 }
2954
2955 DO_SIGNAL_CHECK(SR_signum);
2956 }
2957
2958 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
2959
2960 static os_sigaction_t os_sigaction = NULL;
2961
2962 void os::Bsd::check_signal_handler(int sig) {
2963 char buf[O_BUFLEN];
2964 address jvmHandler = NULL;
2965
2966
2967 struct sigaction act;
2968 if (os_sigaction == NULL) {
2969 // only trust the default sigaction, in case it has been interposed
2970 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
2971 if (os_sigaction == NULL) return;
2972 }
2973
2974 os_sigaction(sig, (struct sigaction*)NULL, &act);
2975
2976
2977 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
2978
2979 address thisHandler = (act.sa_flags & SA_SIGINFO)
2980 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
2981 : CAST_FROM_FN_PTR(address, act.sa_handler);
2982
2983
2984 switch (sig) {
2985 case SIGSEGV:
2986 case SIGBUS:
2987 case SIGFPE:
2988 case SIGPIPE:
2989 case SIGILL:
2990 case SIGXFSZ:
2991 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
2992 break;
2993
2994 case SHUTDOWN1_SIGNAL:
2995 case SHUTDOWN2_SIGNAL:
2996 case SHUTDOWN3_SIGNAL:
2997 case BREAK_SIGNAL:
2998 jvmHandler = (address)user_handler();
2999 break;
3000
3001 default:
3002 if (sig == SR_signum) {
3003 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3004 } else {
3005 return;
3006 }
3007 break;
3008 }
3009
3010 if (thisHandler != jvmHandler) {
3011 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3012 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3013 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3014 // No need to check this sig any longer
3015 sigaddset(&check_signal_done, sig);
3016 // Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN
3017 if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) {
3018 tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell",
3019 exception_name(sig, buf, O_BUFLEN));
3020 }
3021 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3022 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3023 tty->print("expected:");
3024 os::Posix::print_sa_flags(tty, os::Bsd::get_our_sigflags(sig));
3025 tty->cr();
3026 tty->print(" found:");
3027 os::Posix::print_sa_flags(tty, act.sa_flags);
3028 tty->cr();
3029 // No need to check this sig any longer
3030 sigaddset(&check_signal_done, sig);
3031 }
3032
3033 // Dump all the signal
3034 if (sigismember(&check_signal_done, sig)) {
3035 print_signal_handlers(tty, buf, O_BUFLEN);
3036 }
3037 }
3038
3039 extern void report_error(char* file_name, int line_no, char* title,
3040 char* format, ...);
3041
3042 // this is called _before_ the most of global arguments have been parsed
3043 void os::init(void) {
3044 char dummy; // used to get a guess on initial stack address
3045
3046 clock_tics_per_sec = CLK_TCK;
3047
3048 init_random(1234567);
3049
3050 Bsd::set_page_size(getpagesize());
3051 if (Bsd::page_size() == -1) {
3052 fatal("os_bsd.cpp: os::init: sysconf failed (%s)", os::strerror(errno));
3053 }
3054 init_page_sizes((size_t) Bsd::page_size());
3055
3056 Bsd::initialize_system_info();
3057
3058 // _main_thread points to the thread that created/loaded the JVM.
3059 Bsd::_main_thread = pthread_self();
3060
3061 Bsd::clock_init();
3062 initial_time_count = javaTimeNanos();
3063
3064 os::Posix::init();
3065 }
3066
3067 // To install functions for atexit system call
3068 extern "C" {
3069 static void perfMemory_exit_helper() {
3070 perfMemory_exit();
3071 }
3072 }
3073
3074 // this is called _after_ the global arguments have been parsed
3075 jint os::init_2(void) {
3076
3077 // This could be set after os::Posix::init() but all platforms
3078 // have to set it the same so we have to mirror Solaris.
3079 DEBUG_ONLY(os::set_mutex_init_done();)
3080
3081 os::Posix::init_2();
3082
3083 // initialize suspend/resume support - must do this before signal_sets_init()
3084 if (SR_initialize() != 0) {
3085 perror("SR_initialize failed");
3086 return JNI_ERR;
3087 }
3088
3089 Bsd::signal_sets_init();
3090 Bsd::install_signal_handlers();
3091 // Initialize data for jdk.internal.misc.Signal
3092 if (!ReduceSignalUsage) {
3093 jdk_misc_signal_init();
3094 }
3095
3096 // Check and sets minimum stack sizes against command line options
3097 if (Posix::set_minimum_stack_sizes() == JNI_ERR) {
3098 return JNI_ERR;
3099 }
3100
3101 // Not supported.
3102 FLAG_SET_ERGO(UseNUMA, false);
3103 FLAG_SET_ERGO(UseNUMAInterleaving, false);
3104
3105 if (MaxFDLimit) {
3106 // set the number of file descriptors to max. print out error
3107 // if getrlimit/setrlimit fails but continue regardless.
3108 struct rlimit nbr_files;
3109 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3110 if (status != 0) {
3111 log_info(os)("os::init_2 getrlimit failed: %s", os::strerror(errno));
3112 } else {
3113 nbr_files.rlim_cur = nbr_files.rlim_max;
3114
3115 #ifdef __APPLE__
3116 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3117 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3118 // be used instead
3119 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3120 #endif
3121
3122 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3123 if (status != 0) {
3124 log_info(os)("os::init_2 setrlimit failed: %s", os::strerror(errno));
3125 }
3126 }
3127 }
3128
3129 // at-exit methods are called in the reverse order of their registration.
3130 // atexit functions are called on return from main or as a result of a
3131 // call to exit(3C). There can be only 32 of these functions registered
3132 // and atexit() does not set errno.
3133
3134 if (PerfAllowAtExitRegistration) {
3135 // only register atexit functions if PerfAllowAtExitRegistration is set.
3136 // atexit functions can be delayed until process exit time, which
3137 // can be problematic for embedded VM situations. Embedded VMs should
3138 // call DestroyJavaVM() to assure that VM resources are released.
3139
3140 // note: perfMemory_exit_helper atexit function may be removed in
3141 // the future if the appropriate cleanup code can be added to the
3142 // VM_Exit VMOperation's doit method.
3143 if (atexit(perfMemory_exit_helper) != 0) {
3144 warning("os::init_2 atexit(perfMemory_exit_helper) failed");
3145 }
3146 }
3147
3148 // initialize thread priority policy
3149 prio_init();
3150
3151 #ifdef __APPLE__
3152 // dynamically link to objective c gc registration
3153 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3154 if (handleLibObjc != NULL) {
3155 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3156 }
3157 #endif
3158
3159 return JNI_OK;
3160 }
3161
3162 int os::active_processor_count() {
3163 // User has overridden the number of active processors
3164 if (ActiveProcessorCount > 0) {
3165 log_trace(os)("active_processor_count: "
3166 "active processor count set by user : %d",
3167 ActiveProcessorCount);
3168 return ActiveProcessorCount;
3169 }
3170
3171 return _processor_count;
3172 }
3173
3174 #ifdef __APPLE__
3175 uint os::processor_id() {
3176 // Get the initial APIC id and return the associated processor id. The initial APIC
3177 // id is limited to 8-bits, which means we can have at most 256 unique APIC ids. If
3178 // the system has more processors (or the initial APIC ids are discontiguous) the
3179 // APIC id will be truncated and more than one processor will potentially share the
3180 // same processor id. This is not optimal, but unlikely to happen in practice. Should
3181 // this become a real problem we could switch to using x2APIC ids, which are 32-bit
3182 // wide. However, note that x2APIC is Intel-specific, and the wider number space
3183 // would require a more complicated mapping approach.
3184 uint eax = 0x1;
3185 uint ebx;
3186 uint ecx = 0;
3187 uint edx;
3188
3189 __asm__ ("cpuid\n\t" : "+a" (eax), "+b" (ebx), "+c" (ecx), "+d" (edx) : );
3190
3191 uint apic_id = (ebx >> 24) & (processor_id_map_size - 1);
3192 int processor_id = Atomic::load(&processor_id_map[apic_id]);
3193
3194 while (processor_id < 0) {
3195 // Assign processor id to APIC id
3196 processor_id = Atomic::cmpxchg(&processor_id_map[apic_id], processor_id_unassigned, processor_id_assigning);
3197 if (processor_id == processor_id_unassigned) {
3198 processor_id = Atomic::fetch_and_add(&processor_id_next, 1) % os::processor_count();
3199 Atomic::store(&processor_id_map[apic_id], processor_id);
3200 }
3201 }
3202
3203 assert(processor_id >= 0 && processor_id < os::processor_count(), "invalid processor id");
3204
3205 return (uint)processor_id;
3206 }
3207 #endif
3208
3209 void os::set_native_thread_name(const char *name) {
3210 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3211 // This is only supported in Snow Leopard and beyond
3212 if (name != NULL) {
3213 // Add a "Java: " prefix to the name
3214 char buf[MAXTHREADNAMESIZE];
3215 snprintf(buf, sizeof(buf), "Java: %s", name);
3216 pthread_setname_np(buf);
3217 }
3218 #endif
3219 }
3220
3221 bool os::bind_to_processor(uint processor_id) {
3222 // Not yet implemented.
3223 return false;
3224 }
3225
3226 void os::SuspendedThreadTask::internal_do_task() {
3227 if (do_suspend(_thread->osthread())) {
3228 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
3229 do_task(context);
3230 do_resume(_thread->osthread());
3231 }
3232 }
3233
3234 ////////////////////////////////////////////////////////////////////////////////
3235 // debug support
3236
3237 bool os::find(address addr, outputStream* st) {
3238 Dl_info dlinfo;
3239 memset(&dlinfo, 0, sizeof(dlinfo));
3240 if (dladdr(addr, &dlinfo) != 0) {
3241 st->print(INTPTR_FORMAT ": ", (intptr_t)addr);
3242 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) {
3243 st->print("%s+%#x", dlinfo.dli_sname,
3244 (uint)((uintptr_t)addr - (uintptr_t)dlinfo.dli_saddr));
3245 } else if (dlinfo.dli_fbase != NULL) {
3246 st->print("<offset %#x>", (uint)((uintptr_t)addr - (uintptr_t)dlinfo.dli_fbase));
3247 } else {
3248 st->print("<absolute address>");
3249 }
3250 if (dlinfo.dli_fname != NULL) {
3251 st->print(" in %s", dlinfo.dli_fname);
3252 }
3253 if (dlinfo.dli_fbase != NULL) {
3254 st->print(" at " INTPTR_FORMAT, (intptr_t)dlinfo.dli_fbase);
3255 }
3256 st->cr();
3257
3258 if (Verbose) {
3259 // decode some bytes around the PC
3260 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
3261 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size());
3262 address lowest = (address) dlinfo.dli_sname;
3263 if (!lowest) lowest = (address) dlinfo.dli_fbase;
3264 if (begin < lowest) begin = lowest;
3265 Dl_info dlinfo2;
3266 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr
3267 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) {
3268 end = (address) dlinfo2.dli_saddr;
3269 }
3270 Disassembler::decode(begin, end, st);
3271 }
3272 return true;
3273 }
3274 return false;
3275 }
3276
3277 ////////////////////////////////////////////////////////////////////////////////
3278 // misc
3279
3280 // This does not do anything on Bsd. This is basically a hook for being
3281 // able to use structured exception handling (thread-local exception filters)
3282 // on, e.g., Win32.
3283 void os::os_exception_wrapper(java_call_t f, JavaValue* value,
3284 const methodHandle& method, JavaCallArguments* args,
3285 Thread* thread) {
3286 f(value, method, args, thread);
3287 }
3288
3289 void os::print_statistics() {
3290 }
3291
3292 bool os::message_box(const char* title, const char* message) {
3293 int i;
3294 fdStream err(defaultStream::error_fd());
3295 for (i = 0; i < 78; i++) err.print_raw("=");
3296 err.cr();
3297 err.print_raw_cr(title);
3298 for (i = 0; i < 78; i++) err.print_raw("-");
3299 err.cr();
3300 err.print_raw_cr(message);
3301 for (i = 0; i < 78; i++) err.print_raw("=");
3302 err.cr();
3303
3304 char buf[16];
3305 // Prevent process from exiting upon "read error" without consuming all CPU
3306 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3307
3308 return buf[0] == 'y' || buf[0] == 'Y';
3309 }
3310
3311 static inline struct timespec get_mtime(const char* filename) {
3312 struct stat st;
3313 int ret = os::stat(filename, &st);
3314 assert(ret == 0, "failed to stat() file '%s': %s", filename, os::strerror(errno));
3315 #ifdef __APPLE__
3316 return st.st_mtimespec;
3317 #else
3318 return st.st_mtim;
3319 #endif
3320 }
3321
3322 int os::compare_file_modified_times(const char* file1, const char* file2) {
3323 struct timespec filetime1 = get_mtime(file1);
3324 struct timespec filetime2 = get_mtime(file2);
3325 int diff = filetime1.tv_sec - filetime2.tv_sec;
3326 if (diff == 0) {
3327 return filetime1.tv_nsec - filetime2.tv_nsec;
3328 }
3329 return diff;
3330 }
3331
3332 // Is a (classpath) directory empty?
3333 bool os::dir_is_empty(const char* path) {
3334 DIR *dir = NULL;
3335 struct dirent *ptr;
3336
3337 dir = opendir(path);
3338 if (dir == NULL) return true;
3339
3340 // Scan the directory
3341 bool result = true;
3342 while (result && (ptr = readdir(dir)) != NULL) {
3343 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3344 result = false;
3345 }
3346 }
3347 closedir(dir);
3348 return result;
3349 }
3350
3351 // This code originates from JDK's sysOpen and open64_w
3352 // from src/solaris/hpi/src/system_md.c
3353
3354 int os::open(const char *path, int oflag, int mode) {
3355 if (strlen(path) > MAX_PATH - 1) {
3356 errno = ENAMETOOLONG;
3357 return -1;
3358 }
3359 int fd;
3360
3361 fd = ::open(path, oflag, mode);
3362 if (fd == -1) return -1;
3363
3364 // If the open succeeded, the file might still be a directory
3365 {
3366 struct stat buf;
3367 int ret = ::fstat(fd, &buf);
3368 int st_mode = buf.st_mode;
3369
3370 if (ret != -1) {
3371 if ((st_mode & S_IFMT) == S_IFDIR) {
3372 errno = EISDIR;
3373 ::close(fd);
3374 return -1;
3375 }
3376 } else {
3377 ::close(fd);
3378 return -1;
3379 }
3380 }
3381
3382 // All file descriptors that are opened in the JVM and not
3383 // specifically destined for a subprocess should have the
3384 // close-on-exec flag set. If we don't set it, then careless 3rd
3385 // party native code might fork and exec without closing all
3386 // appropriate file descriptors (e.g. as we do in closeDescriptors in
3387 // UNIXProcess.c), and this in turn might:
3388 //
3389 // - cause end-of-file to fail to be detected on some file
3390 // descriptors, resulting in mysterious hangs, or
3391 //
3392 // - might cause an fopen in the subprocess to fail on a system
3393 // suffering from bug 1085341.
3394 //
3395 // (Yes, the default setting of the close-on-exec flag is a Unix
3396 // design flaw)
3397 //
3398 // See:
3399 // 1085341: 32-bit stdio routines should support file descriptors >255
3400 // 4843136: (process) pipe file descriptor from Runtime.exec not being closed
3401 // 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
3402 //
3403 #ifdef FD_CLOEXEC
3404 {
3405 int flags = ::fcntl(fd, F_GETFD);
3406 if (flags != -1) {
3407 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
3408 }
3409 }
3410 #endif
3411
3412 return fd;
3413 }
3414
3415
3416 // create binary file, rewriting existing file if required
3417 int os::create_binary_file(const char* path, bool rewrite_existing) {
3418 int oflags = O_WRONLY | O_CREAT;
3419 if (!rewrite_existing) {
3420 oflags |= O_EXCL;
3421 }
3422 return ::open(path, oflags, S_IREAD | S_IWRITE);
3423 }
3424
3425 // return current position of file pointer
3426 jlong os::current_file_offset(int fd) {
3427 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
3428 }
3429
3430 // move file pointer to the specified offset
3431 jlong os::seek_to_file_offset(int fd, jlong offset) {
3432 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
3433 }
3434
3435 // This code originates from JDK's sysAvailable
3436 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
3437
3438 int os::available(int fd, jlong *bytes) {
3439 jlong cur, end;
3440 int mode;
3441 struct stat buf;
3442
3443 if (::fstat(fd, &buf) >= 0) {
3444 mode = buf.st_mode;
3445 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
3446 int n;
3447 if (::ioctl(fd, FIONREAD, &n) >= 0) {
3448 *bytes = n;
3449 return 1;
3450 }
3451 }
3452 }
3453 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
3454 return 0;
3455 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
3456 return 0;
3457 } else if (::lseek(fd, cur, SEEK_SET) == -1) {
3458 return 0;
3459 }
3460 *bytes = end - cur;
3461 return 1;
3462 }
3463
3464 // Map a block of memory.
3465 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
3466 char *addr, size_t bytes, bool read_only,
3467 bool allow_exec) {
3468 int prot;
3469 int flags;
3470
3471 if (read_only) {
3472 prot = PROT_READ;
3473 flags = MAP_SHARED;
3474 } else {
3475 prot = PROT_READ | PROT_WRITE;
3476 flags = MAP_PRIVATE;
3477 }
3478
3479 if (allow_exec) {
3480 prot |= PROT_EXEC;
3481 }
3482
3483 if (addr != NULL) {
3484 flags |= MAP_FIXED;
3485 }
3486
3487 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
3488 fd, file_offset);
3489 if (mapped_address == MAP_FAILED) {
3490 return NULL;
3491 }
3492 return mapped_address;
3493 }
3494
3495
3496 // Remap a block of memory.
3497 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
3498 char *addr, size_t bytes, bool read_only,
3499 bool allow_exec) {
3500 // same as map_memory() on this OS
3501 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
3502 allow_exec);
3503 }
3504
3505
3506 // Unmap a block of memory.
3507 bool os::pd_unmap_memory(char* addr, size_t bytes) {
3508 return munmap(addr, bytes) == 0;
3509 }
3510
3511 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
3512 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
3513 // of a thread.
3514 //
3515 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
3516 // the fast estimate available on the platform.
3517
3518 jlong os::current_thread_cpu_time() {
3519 #ifdef __APPLE__
3520 return os::thread_cpu_time(Thread::current(), true /* user + sys */);
3521 #else
3522 Unimplemented();
3523 return 0;
3524 #endif
3525 }
3526
3527 jlong os::thread_cpu_time(Thread* thread) {
3528 #ifdef __APPLE__
3529 return os::thread_cpu_time(thread, true /* user + sys */);
3530 #else
3531 Unimplemented();
3532 return 0;
3533 #endif
3534 }
3535
3536 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
3537 #ifdef __APPLE__
3538 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
3539 #else
3540 Unimplemented();
3541 return 0;
3542 #endif
3543 }
3544
3545 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
3546 #ifdef __APPLE__
3547 struct thread_basic_info tinfo;
3548 mach_msg_type_number_t tcount = THREAD_INFO_MAX;
3549 kern_return_t kr;
3550 thread_t mach_thread;
3551
3552 mach_thread = thread->osthread()->thread_id();
3553 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
3554 if (kr != KERN_SUCCESS) {
3555 return -1;
3556 }
3557
3558 if (user_sys_cpu_time) {
3559 jlong nanos;
3560 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
3561 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
3562 return nanos;
3563 } else {
3564 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
3565 }
3566 #else
3567 Unimplemented();
3568 return 0;
3569 #endif
3570 }
3571
3572
3573 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
3574 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
3575 info_ptr->may_skip_backward = false; // elapsed time not wall time
3576 info_ptr->may_skip_forward = false; // elapsed time not wall time
3577 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
3578 }
3579
3580 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
3581 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
3582 info_ptr->may_skip_backward = false; // elapsed time not wall time
3583 info_ptr->may_skip_forward = false; // elapsed time not wall time
3584 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
3585 }
3586
3587 bool os::is_thread_cpu_time_supported() {
3588 #ifdef __APPLE__
3589 return true;
3590 #else
3591 return false;
3592 #endif
3593 }
3594
3595 // System loadavg support. Returns -1 if load average cannot be obtained.
3596 // Bsd doesn't yet have a (official) notion of processor sets,
3597 // so just return the system wide load average.
3598 int os::loadavg(double loadavg[], int nelem) {
3599 return ::getloadavg(loadavg, nelem);
3600 }
3601
3602 void os::pause() {
3603 char filename[MAX_PATH];
3604 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
3605 jio_snprintf(filename, MAX_PATH, "%s", PauseAtStartupFile);
3606 } else {
3607 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
3608 }
3609
3610 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
3611 if (fd != -1) {
3612 struct stat buf;
3613 ::close(fd);
3614 while (::stat(filename, &buf) == 0) {
3615 (void)::poll(NULL, 0, 100);
3616 }
3617 } else {
3618 jio_fprintf(stderr,
3619 "Could not open pause file '%s', continuing immediately.\n", filename);
3620 }
3621 }
3622
3623 // Darwin has no "environ" in a dynamic library.
3624 #ifdef __APPLE__
3625 #include <crt_externs.h>
3626 #define environ (*_NSGetEnviron())
3627 #else
3628 extern char** environ;
3629 #endif
3630
3631 // Run the specified command in a separate process. Return its exit value,
3632 // or -1 on failure (e.g. can't fork a new process).
3633 // Unlike system(), this function can be called from signal handler. It
3634 // doesn't block SIGINT et al.
3635 int os::fork_and_exec(char* cmd, bool use_vfork_if_available) {
3636 const char * argv[4] = {"sh", "-c", cmd, NULL};
3637
3638 // fork() in BsdThreads/NPTL is not async-safe. It needs to run
3639 // pthread_atfork handlers and reset pthread library. All we need is a
3640 // separate process to execve. Make a direct syscall to fork process.
3641 // On IA64 there's no fork syscall, we have to use fork() and hope for
3642 // the best...
3643 pid_t pid = fork();
3644
3645 if (pid < 0) {
3646 // fork failed
3647 return -1;
3648
3649 } else if (pid == 0) {
3650 // child process
3651
3652 // execve() in BsdThreads will call pthread_kill_other_threads_np()
3653 // first to kill every thread on the thread list. Because this list is
3654 // not reset by fork() (see notes above), execve() will instead kill
3655 // every thread in the parent process. We know this is the only thread
3656 // in the new process, so make a system call directly.
3657 // IA64 should use normal execve() from glibc to match the glibc fork()
3658 // above.
3659 execve("/bin/sh", (char* const*)argv, environ);
3660
3661 // execve failed
3662 _exit(-1);
3663
3664 } else {
3665 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
3666 // care about the actual exit code, for now.
3667
3668 int status;
3669
3670 // Wait for the child process to exit. This returns immediately if
3671 // the child has already exited. */
3672 while (waitpid(pid, &status, 0) < 0) {
3673 switch (errno) {
3674 case ECHILD: return 0;
3675 case EINTR: break;
3676 default: return -1;
3677 }
3678 }
3679
3680 if (WIFEXITED(status)) {
3681 // The child exited normally; get its exit code.
3682 return WEXITSTATUS(status);
3683 } else if (WIFSIGNALED(status)) {
3684 // The child exited because of a signal
3685 // The best value to return is 0x80 + signal number,
3686 // because that is what all Unix shells do, and because
3687 // it allows callers to distinguish between process exit and
3688 // process death by signal.
3689 return 0x80 + WTERMSIG(status);
3690 } else {
3691 // Unknown exit code; pass it through
3692 return status;
3693 }
3694 }
3695 }
3696
3697 // Get the kern.corefile setting, or otherwise the default path to the core file
3698 // Returns the length of the string
3699 int os::get_core_path(char* buffer, size_t bufferSize) {
3700 int n = 0;
3701 #ifdef __APPLE__
3702 char coreinfo[MAX_PATH];
3703 size_t sz = sizeof(coreinfo);
3704 int ret = sysctlbyname("kern.corefile", coreinfo, &sz, NULL, 0);
3705 if (ret == 0) {
3706 char *pid_pos = strstr(coreinfo, "%P");
3707 // skip over the "%P" to preserve any optional custom user pattern
3708 const char* tail = (pid_pos != NULL) ? (pid_pos + 2) : "";
3709
3710 if (pid_pos != NULL) {
3711 *pid_pos = '\0';
3712 n = jio_snprintf(buffer, bufferSize, "%s%d%s", coreinfo, os::current_process_id(), tail);
3713 } else {
3714 n = jio_snprintf(buffer, bufferSize, "%s", coreinfo);
3715 }
3716 } else
3717 #endif
3718 {
3719 n = jio_snprintf(buffer, bufferSize, "/cores/core.%d", os::current_process_id());
3720 }
3721 // Truncate if theoretical string was longer than bufferSize
3722 n = MIN2(n, (int)bufferSize);
3723
3724 return n;
3725 }
3726
3727 bool os::supports_map_sync() {
3728 return false;
3729 }
3730
3731 #ifndef PRODUCT
3732 void TestReserveMemorySpecial_test() {
3733 // No tests available for this platform
3734 }
3735 #endif
3736
3737 bool os::start_debugging(char *buf, int buflen) {
3738 int len = (int)strlen(buf);
3739 char *p = &buf[len];
3740
3741 jio_snprintf(p, buflen-len,
3742 "\n\n"
3743 "Do you want to debug the problem?\n\n"
3744 "To debug, run 'gdb /proc/%d/exe %d'; then switch to thread " INTX_FORMAT " (" INTPTR_FORMAT ")\n"
3745 "Enter 'yes' to launch gdb automatically (PATH must include gdb)\n"
3746 "Otherwise, press RETURN to abort...",
3747 os::current_process_id(), os::current_process_id(),
3748 os::current_thread_id(), os::current_thread_id());
3749
3750 bool yes = os::message_box("Unexpected Error", buf);
3751
3752 if (yes) {
3753 // yes, user asked VM to launch debugger
3754 jio_snprintf(buf, sizeof(buf), "gdb /proc/%d/exe %d",
3755 os::current_process_id(), os::current_process_id());
3756
3757 os::fork_and_exec(buf);
3758 yes = false;
3759 }
3760 return yes;
3761 }