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/extendedPC.hpp"
48 #include "runtime/globals.hpp"
49 #include "runtime/interfaceSupport.inline.hpp"
50 #include "runtime/java.hpp"
51 #include "runtime/javaCalls.hpp"
52 #include "runtime/mutexLocker.hpp"
53 #include "runtime/objectMonitor.hpp"
54 #include "runtime/osThread.hpp"
55 #include "runtime/perfMemory.hpp"
56 #include "runtime/semaphore.hpp"
57 #include "runtime/sharedRuntime.hpp"
58 #include "runtime/statSampler.hpp"
59 #include "runtime/stubRoutines.hpp"
60 #include "runtime/thread.inline.hpp"
61 #include "runtime/threadCritical.hpp"
62 #include "runtime/timer.hpp"
63 #include "services/attachListener.hpp"
64 #include "services/memTracker.hpp"
65 #include "services/runtimeService.hpp"
66 #include "utilities/align.hpp"
67 #include "utilities/decoder.hpp"
68 #include "utilities/defaultStream.hpp"
69 #include "utilities/events.hpp"
70 #include "utilities/growableArray.hpp"
71 #include "utilities/vmError.hpp"
72
73 // put OS-includes here
74 # include <dlfcn.h>
75 # include <errno.h>
76 # include <fcntl.h>
77 # include <inttypes.h>
78 # include <poll.h>
79 # include <pthread.h>
80 # include <pwd.h>
81 # include <signal.h>
82 # include <stdint.h>
83 # include <stdio.h>
84 # include <string.h>
85 # include <sys/ioctl.h>
86 # include <sys/mman.h>
87 # include <sys/param.h>
88 # include <sys/resource.h>
89 # include <sys/socket.h>
90 # include <sys/stat.h>
91 # include <sys/syscall.h>
92 # include <sys/sysctl.h>
93 # include <sys/time.h>
94 # include <sys/times.h>
95 # include <sys/types.h>
96 # include <sys/wait.h>
97 # include <time.h>
98 # include <unistd.h>
99
100 #if defined(__FreeBSD__) || defined(__NetBSD__)
101 #include <elf.h>
102 #endif
103
104 #ifdef __APPLE__
105 #include <mach-o/dyld.h>
106 #endif
107
108 #ifndef MAP_ANONYMOUS
109 #define MAP_ANONYMOUS MAP_ANON
110 #endif
111
112 #define MAX_PATH (2 * K)
113
114 // for timer info max values which include all bits
115 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF)
116
117 ////////////////////////////////////////////////////////////////////////////////
118 // global variables
119 julong os::Bsd::_physical_memory = 0;
120
121 #ifdef __APPLE__
122 mach_timebase_info_data_t os::Bsd::_timebase_info = {0, 0};
123 volatile uint64_t os::Bsd::_max_abstime = 0;
124 #else
125 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL;
126 #endif
127 pthread_t os::Bsd::_main_thread;
128 int os::Bsd::_page_size = -1;
129
130 static jlong initial_time_count=0;
131
132 static int clock_tics_per_sec = 100;
133
134 // For diagnostics to print a message once. see run_periodic_checks
135 static sigset_t check_signal_done;
136 static bool check_signals = true;
137
138 // Signal number used to suspend/resume a thread
139
140 // do not use any signal number less than SIGSEGV, see 4355769
141 static int SR_signum = SIGUSR2;
142 sigset_t SR_sigset;
143
144 #ifdef __APPLE__
145 static const int processor_id_unassigned = -1;
146 static const int processor_id_assigning = -2;
147 static const int processor_id_map_size = 256;
148 static volatile int processor_id_map[processor_id_map_size];
149 static volatile int processor_id_next = 0;
150 #endif
151
152 ////////////////////////////////////////////////////////////////////////////////
153 // utility functions
154
155 static int SR_initialize();
156
157 julong os::available_memory() {
158 return Bsd::available_memory();
159 }
160
161 // available here means free
162 julong os::Bsd::available_memory() {
163 uint64_t available = physical_memory() >> 2;
164 #ifdef __APPLE__
165 mach_msg_type_number_t count = HOST_VM_INFO64_COUNT;
166 vm_statistics64_data_t vmstat;
167 kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64,
168 (host_info64_t)&vmstat, &count);
169 assert(kerr == KERN_SUCCESS,
170 "host_statistics64 failed - check mach_host_self() and count");
171 if (kerr == KERN_SUCCESS) {
172 available = vmstat.free_count * os::vm_page_size();
173 }
174 #endif
175 return available;
176 }
177
178 // for more info see :
179 // https://man.openbsd.org/sysctl.2
180 void os::Bsd::print_uptime_info(outputStream* st) {
181 struct timeval boottime;
182 size_t len = sizeof(boottime);
183 int mib[2];
184 mib[0] = CTL_KERN;
185 mib[1] = KERN_BOOTTIME;
186
187 if (sysctl(mib, 2, &boottime, &len, NULL, 0) >= 0) {
188 time_t bootsec = boottime.tv_sec;
189 time_t currsec = time(NULL);
190 os::print_dhm(st, "OS uptime:", (long) difftime(currsec, bootsec));
191 }
192 }
193
194 julong os::physical_memory() {
195 return Bsd::physical_memory();
196 }
197
198 // Return true if user is running as root.
199
200 bool os::have_special_privileges() {
201 static bool init = false;
202 static bool privileges = false;
203 if (!init) {
204 privileges = (getuid() != geteuid()) || (getgid() != getegid());
205 init = true;
206 }
207 return privileges;
208 }
209
210
211
212 // Cpu architecture string
213 #if defined(ZERO)
214 static char cpu_arch[] = ZERO_LIBARCH;
215 #elif defined(IA64)
216 static char cpu_arch[] = "ia64";
217 #elif defined(IA32)
218 static char cpu_arch[] = "i386";
219 #elif defined(AMD64)
220 static char cpu_arch[] = "amd64";
221 #elif defined(ARM)
222 static char cpu_arch[] = "arm";
223 #elif defined(PPC32)
224 static char cpu_arch[] = "ppc";
225 #elif defined(SPARC)
226 #ifdef _LP64
227 static char cpu_arch[] = "sparcv9";
228 #else
229 static char cpu_arch[] = "sparc";
230 #endif
231 #else
232 #error Add appropriate cpu_arch setting
233 #endif
234
235 // Compiler variant
236 #ifdef COMPILER2
237 #define COMPILER_VARIANT "server"
238 #else
239 #define COMPILER_VARIANT "client"
240 #endif
241
242
243 void os::Bsd::initialize_system_info() {
244 int mib[2];
245 size_t len;
246 int cpu_val;
247 julong mem_val;
248
249 // get processors count via hw.ncpus sysctl
250 mib[0] = CTL_HW;
251 mib[1] = HW_NCPU;
252 len = sizeof(cpu_val);
253 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) {
254 assert(len == sizeof(cpu_val), "unexpected data size");
255 set_processor_count(cpu_val);
256 } else {
257 set_processor_count(1); // fallback
258 }
259
260 #ifdef __APPLE__
261 // initialize processor id map
262 for (int i = 0; i < processor_id_map_size; i++) {
263 processor_id_map[i] = processor_id_unassigned;
264 }
265 #endif
266
267 // get physical memory via hw.memsize sysctl (hw.memsize is used
268 // since it returns a 64 bit value)
269 mib[0] = CTL_HW;
270
271 #if defined (HW_MEMSIZE) // Apple
272 mib[1] = HW_MEMSIZE;
273 #elif defined(HW_PHYSMEM) // Most of BSD
274 mib[1] = HW_PHYSMEM;
275 #elif defined(HW_REALMEM) // Old FreeBSD
276 mib[1] = HW_REALMEM;
277 #else
278 #error No ways to get physmem
279 #endif
280
281 len = sizeof(mem_val);
282 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) {
283 assert(len == sizeof(mem_val), "unexpected data size");
284 _physical_memory = mem_val;
285 } else {
286 _physical_memory = 256 * 1024 * 1024; // fallback (XXXBSD?)
287 }
288
289 #ifdef __OpenBSD__
290 {
291 // limit _physical_memory memory view on OpenBSD since
292 // datasize rlimit restricts us anyway.
293 struct rlimit limits;
294 getrlimit(RLIMIT_DATA, &limits);
295 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur);
296 }
297 #endif
298 }
299
300 #ifdef __APPLE__
301 static const char *get_home() {
302 const char *home_dir = ::getenv("HOME");
303 if ((home_dir == NULL) || (*home_dir == '\0')) {
304 struct passwd *passwd_info = getpwuid(geteuid());
305 if (passwd_info != NULL) {
306 home_dir = passwd_info->pw_dir;
307 }
308 }
309
310 return home_dir;
311 }
312 #endif
313
314 void os::init_system_properties_values() {
315 // The next steps are taken in the product version:
316 //
317 // Obtain the JAVA_HOME value from the location of libjvm.so.
318 // This library should be located at:
319 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so.
320 //
321 // If "/jre/lib/" appears at the right place in the path, then we
322 // assume libjvm.so is installed in a JDK and we use this path.
323 //
324 // Otherwise exit with message: "Could not create the Java virtual machine."
325 //
326 // The following extra steps are taken in the debugging version:
327 //
328 // If "/jre/lib/" does NOT appear at the right place in the path
329 // instead of exit check for $JAVA_HOME environment variable.
330 //
331 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>,
332 // then we append a fake suffix "hotspot/libjvm.so" to this path so
333 // it looks like libjvm.so is installed there
334 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so.
335 //
336 // Otherwise exit.
337 //
338 // Important note: if the location of libjvm.so changes this
339 // code needs to be changed accordingly.
340
341 // See ld(1):
342 // The linker uses the following search paths to locate required
343 // shared libraries:
344 // 1: ...
345 // ...
346 // 7: The default directories, normally /lib and /usr/lib.
347 #ifndef DEFAULT_LIBPATH
348 #ifndef OVERRIDE_LIBPATH
349 #define DEFAULT_LIBPATH "/lib:/usr/lib"
350 #else
351 #define DEFAULT_LIBPATH OVERRIDE_LIBPATH
352 #endif
353 #endif
354
355 // Base path of extensions installed on the system.
356 #define SYS_EXT_DIR "/usr/java/packages"
357 #define EXTENSIONS_DIR "/lib/ext"
358
359 #ifndef __APPLE__
360
361 // Buffer that fits several sprintfs.
362 // Note that the space for the colon and the trailing null are provided
363 // by the nulls included by the sizeof operator.
364 const size_t bufsize =
365 MAX2((size_t)MAXPATHLEN, // For dll_dir & friends.
366 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + sizeof(SYS_EXT_DIR) + sizeof(EXTENSIONS_DIR)); // extensions dir
367 char *buf = NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
368
369 // sysclasspath, java_home, dll_dir
370 {
371 char *pslash;
372 os::jvm_path(buf, bufsize);
373
374 // Found the full path to libjvm.so.
375 // Now cut the path to <java_home>/jre if we can.
376 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
377 pslash = strrchr(buf, '/');
378 if (pslash != NULL) {
379 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
380 }
381 Arguments::set_dll_dir(buf);
382
383 if (pslash != NULL) {
384 pslash = strrchr(buf, '/');
385 if (pslash != NULL) {
386 *pslash = '\0'; // Get rid of /<arch>.
387 pslash = strrchr(buf, '/');
388 if (pslash != NULL) {
389 *pslash = '\0'; // Get rid of /lib.
390 }
391 }
392 }
393 Arguments::set_java_home(buf);
394 if (!set_boot_path('/', ':')) {
395 vm_exit_during_initialization("Failed setting boot class path.", NULL);
396 }
397 }
398
399 // Where to look for native libraries.
400 //
401 // Note: Due to a legacy implementation, most of the library path
402 // is set in the launcher. This was to accomodate linking restrictions
403 // on legacy Bsd implementations (which are no longer supported).
404 // Eventually, all the library path setting will be done here.
405 //
406 // However, to prevent the proliferation of improperly built native
407 // libraries, the new path component /usr/java/packages is added here.
408 // Eventually, all the library path setting will be done here.
409 {
410 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
411 // should always exist (until the legacy problem cited above is
412 // addressed).
413 const char *v = ::getenv("LD_LIBRARY_PATH");
414 const char *v_colon = ":";
415 if (v == NULL) { v = ""; v_colon = ""; }
416 // That's +1 for the colon and +1 for the trailing '\0'.
417 char *ld_library_path = NEW_C_HEAP_ARRAY(char,
418 strlen(v) + 1 +
419 sizeof(SYS_EXT_DIR) + sizeof("/lib/") + strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH) + 1,
420 mtInternal);
421 sprintf(ld_library_path, "%s%s" SYS_EXT_DIR "/lib/%s:" DEFAULT_LIBPATH, v, v_colon, cpu_arch);
422 Arguments::set_library_path(ld_library_path);
423 FREE_C_HEAP_ARRAY(char, ld_library_path);
424 }
425
426 // Extensions directories.
427 sprintf(buf, "%s" EXTENSIONS_DIR ":" SYS_EXT_DIR EXTENSIONS_DIR, Arguments::get_java_home());
428 Arguments::set_ext_dirs(buf);
429
430 FREE_C_HEAP_ARRAY(char, buf);
431
432 #else // __APPLE__
433
434 #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions"
435 #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java"
436
437 const char *user_home_dir = get_home();
438 // The null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir.
439 size_t system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) +
440 sizeof(SYS_EXTENSIONS_DIRS);
441
442 // Buffer that fits several sprintfs.
443 // Note that the space for the colon and the trailing null are provided
444 // by the nulls included by the sizeof operator.
445 const size_t bufsize =
446 MAX2((size_t)MAXPATHLEN, // for dll_dir & friends.
447 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + system_ext_size); // extensions dir
448 char *buf = NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
449
450 // sysclasspath, java_home, dll_dir
451 {
452 char *pslash;
453 os::jvm_path(buf, bufsize);
454
455 // Found the full path to libjvm.so.
456 // Now cut the path to <java_home>/jre if we can.
457 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
458 pslash = strrchr(buf, '/');
459 if (pslash != NULL) {
460 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
461 }
462 #ifdef STATIC_BUILD
463 strcat(buf, "/lib");
464 #endif
465
466 Arguments::set_dll_dir(buf);
467
468 if (pslash != NULL) {
469 pslash = strrchr(buf, '/');
470 if (pslash != NULL) {
471 *pslash = '\0'; // Get rid of /lib.
472 }
473 }
474 Arguments::set_java_home(buf);
475 set_boot_path('/', ':');
476 }
477
478 // Where to look for native libraries.
479 //
480 // Note: Due to a legacy implementation, most of the library path
481 // is set in the launcher. This was to accomodate linking restrictions
482 // on legacy Bsd implementations (which are no longer supported).
483 // Eventually, all the library path setting will be done here.
484 //
485 // However, to prevent the proliferation of improperly built native
486 // libraries, the new path component /usr/java/packages is added here.
487 // Eventually, all the library path setting will be done here.
488 {
489 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
490 // should always exist (until the legacy problem cited above is
491 // addressed).
492 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code
493 // can specify a directory inside an app wrapper
494 const char *l = ::getenv("JAVA_LIBRARY_PATH");
495 const char *l_colon = ":";
496 if (l == NULL) { l = ""; l_colon = ""; }
497
498 const char *v = ::getenv("DYLD_LIBRARY_PATH");
499 const char *v_colon = ":";
500 if (v == NULL) { v = ""; v_colon = ""; }
501
502 // Apple's Java6 has "." at the beginning of java.library.path.
503 // OpenJDK on Windows has "." at the end of java.library.path.
504 // OpenJDK on Linux and Solaris don't have "." in java.library.path
505 // at all. To ease the transition from Apple's Java6 to OpenJDK7,
506 // "." is appended to the end of java.library.path. Yes, this
507 // could cause a change in behavior, but Apple's Java6 behavior
508 // can be achieved by putting "." at the beginning of the
509 // JAVA_LIBRARY_PATH environment variable.
510 char *ld_library_path = NEW_C_HEAP_ARRAY(char,
511 strlen(v) + 1 + strlen(l) + 1 +
512 system_ext_size + 3,
513 mtInternal);
514 sprintf(ld_library_path, "%s%s%s%s%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS ":.",
515 v, v_colon, l, l_colon, user_home_dir);
516 Arguments::set_library_path(ld_library_path);
517 FREE_C_HEAP_ARRAY(char, ld_library_path);
518 }
519
520 // Extensions directories.
521 //
522 // Note that the space for the colon and the trailing null are provided
523 // by the nulls included by the sizeof operator (so actually one byte more
524 // than necessary is allocated).
525 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS,
526 user_home_dir, Arguments::get_java_home());
527 Arguments::set_ext_dirs(buf);
528
529 FREE_C_HEAP_ARRAY(char, buf);
530
531 #undef SYS_EXTENSIONS_DIR
532 #undef SYS_EXTENSIONS_DIRS
533
534 #endif // __APPLE__
535
536 #undef SYS_EXT_DIR
537 #undef EXTENSIONS_DIR
538 }
539
540 ////////////////////////////////////////////////////////////////////////////////
541 // breakpoint support
542
543 void os::breakpoint() {
544 BREAKPOINT;
545 }
546
547 extern "C" void breakpoint() {
548 // use debugger to set breakpoint here
549 }
550
551 ////////////////////////////////////////////////////////////////////////////////
552 // signal support
553
554 debug_only(static bool signal_sets_initialized = false);
555 static sigset_t unblocked_sigs, vm_sigs;
556
557 void os::Bsd::signal_sets_init() {
558 // Should also have an assertion stating we are still single-threaded.
559 assert(!signal_sets_initialized, "Already initialized");
560 // Fill in signals that are necessarily unblocked for all threads in
561 // the VM. Currently, we unblock the following signals:
562 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
563 // by -Xrs (=ReduceSignalUsage));
564 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
565 // other threads. The "ReduceSignalUsage" boolean tells us not to alter
566 // the dispositions or masks wrt these signals.
567 // Programs embedding the VM that want to use the above signals for their
568 // own purposes must, at this time, use the "-Xrs" option to prevent
569 // interference with shutdown hooks and BREAK_SIGNAL thread dumping.
570 // (See bug 4345157, and other related bugs).
571 // In reality, though, unblocking these signals is really a nop, since
572 // these signals are not blocked by default.
573 sigemptyset(&unblocked_sigs);
574 sigaddset(&unblocked_sigs, SIGILL);
575 sigaddset(&unblocked_sigs, SIGSEGV);
576 sigaddset(&unblocked_sigs, SIGBUS);
577 sigaddset(&unblocked_sigs, SIGFPE);
578 sigaddset(&unblocked_sigs, SR_signum);
579
580 if (!ReduceSignalUsage) {
581 if (!os::Posix::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
582 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
583
584 }
585 if (!os::Posix::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
586 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
587 }
588 if (!os::Posix::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
589 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
590 }
591 }
592 // Fill in signals that are blocked by all but the VM thread.
593 sigemptyset(&vm_sigs);
594 if (!ReduceSignalUsage) {
595 sigaddset(&vm_sigs, BREAK_SIGNAL);
596 }
597 debug_only(signal_sets_initialized = true);
598
599 }
600
601 // These are signals that are unblocked while a thread is running Java.
602 // (For some reason, they get blocked by default.)
603 sigset_t* os::Bsd::unblocked_signals() {
604 assert(signal_sets_initialized, "Not initialized");
605 return &unblocked_sigs;
606 }
607
608 // These are the signals that are blocked while a (non-VM) thread is
609 // running Java. Only the VM thread handles these signals.
610 sigset_t* os::Bsd::vm_signals() {
611 assert(signal_sets_initialized, "Not initialized");
612 return &vm_sigs;
613 }
614
615 void os::Bsd::hotspot_sigmask(Thread* thread) {
616
617 //Save caller's signal mask before setting VM signal mask
618 sigset_t caller_sigmask;
619 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
620
621 OSThread* osthread = thread->osthread();
622 osthread->set_caller_sigmask(caller_sigmask);
623
624 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL);
625
626 if (!ReduceSignalUsage) {
627 if (thread->is_VM_thread()) {
628 // Only the VM thread handles BREAK_SIGNAL ...
629 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
630 } else {
631 // ... all other threads block BREAK_SIGNAL
632 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
633 }
634 }
635 }
636
637
638 //////////////////////////////////////////////////////////////////////////////
639 // create new thread
640
641 #ifdef __APPLE__
642 // library handle for calling objc_registerThreadWithCollector()
643 // without static linking to the libobjc library
644 #define OBJC_LIB "/usr/lib/libobjc.dylib"
645 #define OBJC_GCREGISTER "objc_registerThreadWithCollector"
646 typedef void (*objc_registerThreadWithCollector_t)();
647 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction;
648 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL;
649 #endif
650
651 // Thread start routine for all newly created threads
652 static void *thread_native_entry(Thread *thread) {
653
654 thread->record_stack_base_and_size();
655
656 // Try to randomize the cache line index of hot stack frames.
657 // This helps when threads of the same stack traces evict each other's
658 // cache lines. The threads can be either from the same JVM instance, or
659 // from different JVM instances. The benefit is especially true for
660 // processors with hyperthreading technology.
661 static int counter = 0;
662 int pid = os::current_process_id();
663 alloca(((pid ^ counter++) & 7) * 128);
664
665 thread->initialize_thread_current();
666
667 OSThread* osthread = thread->osthread();
668 Monitor* sync = osthread->startThread_lock();
669
670 osthread->set_thread_id(os::Bsd::gettid());
671
672 log_info(os, thread)("Thread is alive (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").",
673 os::current_thread_id(), (uintx) pthread_self());
674
675 #ifdef __APPLE__
676 // Store unique OS X thread id used by SA
677 osthread->set_unique_thread_id();
678 #endif
679
680 // initialize signal mask for this thread
681 os::Bsd::hotspot_sigmask(thread);
682
683 // initialize floating point control register
684 os::Bsd::init_thread_fpu_state();
685
686 #ifdef __APPLE__
687 // register thread with objc gc
688 if (objc_registerThreadWithCollectorFunction != NULL) {
689 objc_registerThreadWithCollectorFunction();
690 }
691 #endif
692
693 // handshaking with parent thread
694 {
695 MutexLocker ml(sync, Mutex::_no_safepoint_check_flag);
696
697 // notify parent thread
698 osthread->set_state(INITIALIZED);
699 sync->notify_all();
700
701 // wait until os::start_thread()
702 while (osthread->get_state() == INITIALIZED) {
703 sync->wait_without_safepoint_check();
704 }
705 }
706
707 // call one more level start routine
708 thread->call_run();
709
710 // Note: at this point the thread object may already have deleted itself.
711 // Prevent dereferencing it from here on out.
712 thread = NULL;
713
714 log_info(os, thread)("Thread finished (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").",
715 os::current_thread_id(), (uintx) pthread_self());
716
717 return 0;
718 }
719
720 bool os::create_thread(Thread* thread, ThreadType thr_type,
721 size_t req_stack_size) {
722 assert(thread->osthread() == NULL, "caller responsible");
723
724 // Allocate the OSThread object
725 OSThread* osthread = new OSThread(NULL, NULL);
726 if (osthread == NULL) {
727 return false;
728 }
729
730 // set the correct thread state
731 osthread->set_thread_type(thr_type);
732
733 // Initial state is ALLOCATED but not INITIALIZED
734 osthread->set_state(ALLOCATED);
735
736 thread->set_osthread(osthread);
737
738 // init thread attributes
739 pthread_attr_t attr;
740 pthread_attr_init(&attr);
741 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
742
743 // calculate stack size if it's not specified by caller
744 size_t stack_size = os::Posix::get_initial_stack_size(thr_type, req_stack_size);
745 int status = pthread_attr_setstacksize(&attr, stack_size);
746 assert_status(status == 0, status, "pthread_attr_setstacksize");
747
748 ThreadState state;
749
750 {
751 pthread_t tid;
752 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) thread_native_entry, thread);
753
754 char buf[64];
755 if (ret == 0) {
756 log_info(os, thread)("Thread started (pthread id: " UINTX_FORMAT ", attributes: %s). ",
757 (uintx) tid, os::Posix::describe_pthread_attr(buf, sizeof(buf), &attr));
758 } else {
759 log_warning(os, thread)("Failed to start thread - pthread_create failed (%s) for attributes: %s.",
760 os::errno_name(ret), os::Posix::describe_pthread_attr(buf, sizeof(buf), &attr));
761 // Log some OS information which might explain why creating the thread failed.
762 log_info(os, thread)("Number of threads approx. running in the VM: %d", Threads::number_of_threads());
763 LogStream st(Log(os, thread)::info());
764 os::Posix::print_rlimit_info(&st);
765 os::print_memory_info(&st);
766 }
767
768 pthread_attr_destroy(&attr);
769
770 if (ret != 0) {
771 // Need to clean up stuff we've allocated so far
772 thread->set_osthread(NULL);
773 delete osthread;
774 return false;
775 }
776
777 // Store pthread info into the OSThread
778 osthread->set_pthread_id(tid);
779
780 // Wait until child thread is either initialized or aborted
781 {
782 Monitor* sync_with_child = osthread->startThread_lock();
783 MutexLocker ml(sync_with_child, Mutex::_no_safepoint_check_flag);
784 while ((state = osthread->get_state()) == ALLOCATED) {
785 sync_with_child->wait_without_safepoint_check();
786 }
787 }
788
789 }
790
791 // Aborted due to thread limit being reached
792 if (state == ZOMBIE) {
793 thread->set_osthread(NULL);
794 delete osthread;
795 return false;
796 }
797
798 // The thread is returned suspended (in state INITIALIZED),
799 // and is started higher up in the call chain
800 assert(state == INITIALIZED, "race condition");
801 return true;
802 }
803
804 /////////////////////////////////////////////////////////////////////////////
805 // attach existing thread
806
807 // bootstrap the main thread
808 bool os::create_main_thread(JavaThread* thread) {
809 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
810 return create_attached_thread(thread);
811 }
812
813 bool os::create_attached_thread(JavaThread* thread) {
814 #ifdef ASSERT
815 thread->verify_not_published();
816 #endif
817
818 // Allocate the OSThread object
819 OSThread* osthread = new OSThread(NULL, NULL);
820
821 if (osthread == NULL) {
822 return false;
823 }
824
825 osthread->set_thread_id(os::Bsd::gettid());
826
827 #ifdef __APPLE__
828 // Store unique OS X thread id used by SA
829 osthread->set_unique_thread_id();
830 #endif
831
832 // Store pthread info into the OSThread
833 osthread->set_pthread_id(::pthread_self());
834
835 // initialize floating point control register
836 os::Bsd::init_thread_fpu_state();
837
838 // Initial thread state is RUNNABLE
839 osthread->set_state(RUNNABLE);
840
841 thread->set_osthread(osthread);
842
843 // initialize signal mask for this thread
844 // and save the caller's signal mask
845 os::Bsd::hotspot_sigmask(thread);
846
847 log_info(os, thread)("Thread attached (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").",
848 os::current_thread_id(), (uintx) pthread_self());
849
850 return true;
851 }
852
853 void os::pd_start_thread(Thread* thread) {
854 OSThread * osthread = thread->osthread();
855 assert(osthread->get_state() != INITIALIZED, "just checking");
856 Monitor* sync_with_child = osthread->startThread_lock();
857 MutexLocker ml(sync_with_child, Mutex::_no_safepoint_check_flag);
858 sync_with_child->notify();
859 }
860
861 // Free Bsd resources related to the OSThread
862 void os::free_thread(OSThread* osthread) {
863 assert(osthread != NULL, "osthread not set");
864
865 // We are told to free resources of the argument thread,
866 // but we can only really operate on the current thread.
867 assert(Thread::current()->osthread() == osthread,
868 "os::free_thread but not current thread");
869
870 // Restore caller's signal mask
871 sigset_t sigmask = osthread->caller_sigmask();
872 pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
873
874 delete osthread;
875 }
876
877 ////////////////////////////////////////////////////////////////////////////////
878 // time support
879
880 // Time since start-up in seconds to a fine granularity.
881 // Used by VMSelfDestructTimer and the MemProfiler.
882 double os::elapsedTime() {
883
884 return ((double)os::elapsed_counter()) / os::elapsed_frequency();
885 }
886
887 jlong os::elapsed_counter() {
888 return javaTimeNanos() - initial_time_count;
889 }
890
891 jlong os::elapsed_frequency() {
892 return NANOSECS_PER_SEC; // nanosecond resolution
893 }
894
895 bool os::supports_vtime() { return true; }
896
897 double os::elapsedVTime() {
898 // better than nothing, but not much
899 return elapsedTime();
900 }
901
902 jlong os::javaTimeMillis() {
903 timeval time;
904 int status = gettimeofday(&time, NULL);
905 assert(status != -1, "bsd error");
906 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
907 }
908
909 void os::javaTimeSystemUTC(jlong &seconds, jlong &nanos) {
910 timeval time;
911 int status = gettimeofday(&time, NULL);
912 assert(status != -1, "bsd error");
913 seconds = jlong(time.tv_sec);
914 nanos = jlong(time.tv_usec) * 1000;
915 }
916
917 #ifndef __APPLE__
918 #ifndef CLOCK_MONOTONIC
919 #define CLOCK_MONOTONIC (1)
920 #endif
921 #endif
922
923 #ifdef __APPLE__
924 void os::Bsd::clock_init() {
925 mach_timebase_info(&_timebase_info);
926 }
927 #else
928 void os::Bsd::clock_init() {
929 struct timespec res;
930 struct timespec tp;
931 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
932 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) {
933 // yes, monotonic clock is supported
934 _clock_gettime = ::clock_gettime;
935 }
936 }
937 #endif
938
939
940
941 #ifdef __APPLE__
942
943 jlong os::javaTimeNanos() {
944 const uint64_t tm = mach_absolute_time();
945 const uint64_t now = (tm * Bsd::_timebase_info.numer) / Bsd::_timebase_info.denom;
946 const uint64_t prev = Bsd::_max_abstime;
947 if (now <= prev) {
948 return prev; // same or retrograde time;
949 }
950 const uint64_t obsv = Atomic::cmpxchg(&Bsd::_max_abstime, prev, now);
951 assert(obsv >= prev, "invariant"); // Monotonicity
952 // If the CAS succeeded then we're done and return "now".
953 // If the CAS failed and the observed value "obsv" is >= now then
954 // we should return "obsv". If the CAS failed and now > obsv > prv then
955 // some other thread raced this thread and installed a new value, in which case
956 // we could either (a) retry the entire operation, (b) retry trying to install now
957 // or (c) just return obsv. We use (c). No loop is required although in some cases
958 // we might discard a higher "now" value in deference to a slightly lower but freshly
959 // installed obsv value. That's entirely benign -- it admits no new orderings compared
960 // to (a) or (b) -- and greatly reduces coherence traffic.
961 // We might also condition (c) on the magnitude of the delta between obsv and now.
962 // Avoiding excessive CAS operations to hot RW locations is critical.
963 // See https://blogs.oracle.com/dave/entry/cas_and_cache_trivia_invalidate
964 return (prev == obsv) ? now : obsv;
965 }
966
967 #else // __APPLE__
968
969 jlong os::javaTimeNanos() {
970 if (os::supports_monotonic_clock()) {
971 struct timespec tp;
972 int status = Bsd::_clock_gettime(CLOCK_MONOTONIC, &tp);
973 assert(status == 0, "gettime error");
974 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
975 return result;
976 } else {
977 timeval time;
978 int status = gettimeofday(&time, NULL);
979 assert(status != -1, "bsd error");
980 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
981 return 1000 * usecs;
982 }
983 }
984
985 #endif // __APPLE__
986
987 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
988 if (os::supports_monotonic_clock()) {
989 info_ptr->max_value = ALL_64_BITS;
990
991 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
992 info_ptr->may_skip_backward = false; // not subject to resetting or drifting
993 info_ptr->may_skip_forward = false; // not subject to resetting or drifting
994 } else {
995 // gettimeofday - based on time in seconds since the Epoch thus does not wrap
996 info_ptr->max_value = ALL_64_BITS;
997
998 // gettimeofday is a real time clock so it skips
999 info_ptr->may_skip_backward = true;
1000 info_ptr->may_skip_forward = true;
1001 }
1002
1003 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
1004 }
1005
1006 // Return the real, user, and system times in seconds from an
1007 // arbitrary fixed point in the past.
1008 bool os::getTimesSecs(double* process_real_time,
1009 double* process_user_time,
1010 double* process_system_time) {
1011 struct tms ticks;
1012 clock_t real_ticks = times(&ticks);
1013
1014 if (real_ticks == (clock_t) (-1)) {
1015 return false;
1016 } else {
1017 double ticks_per_second = (double) clock_tics_per_sec;
1018 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1019 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1020 *process_real_time = ((double) real_ticks) / ticks_per_second;
1021
1022 return true;
1023 }
1024 }
1025
1026
1027 char * os::local_time_string(char *buf, size_t buflen) {
1028 struct tm t;
1029 time_t long_time;
1030 time(&long_time);
1031 localtime_r(&long_time, &t);
1032 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1033 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1034 t.tm_hour, t.tm_min, t.tm_sec);
1035 return buf;
1036 }
1037
1038 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
1039 return localtime_r(clock, res);
1040 }
1041
1042 ////////////////////////////////////////////////////////////////////////////////
1043 // runtime exit support
1044
1045 // Note: os::shutdown() might be called very early during initialization, or
1046 // called from signal handler. Before adding something to os::shutdown(), make
1047 // sure it is async-safe and can handle partially initialized VM.
1048 void os::shutdown() {
1049
1050 // allow PerfMemory to attempt cleanup of any persistent resources
1051 perfMemory_exit();
1052
1053 // needs to remove object in file system
1054 AttachListener::abort();
1055
1056 // flush buffered output, finish log files
1057 ostream_abort();
1058
1059 // Check for abort hook
1060 abort_hook_t abort_hook = Arguments::abort_hook();
1061 if (abort_hook != NULL) {
1062 abort_hook();
1063 }
1064
1065 }
1066
1067 // Note: os::abort() might be called very early during initialization, or
1068 // called from signal handler. Before adding something to os::abort(), make
1069 // sure it is async-safe and can handle partially initialized VM.
1070 void os::abort(bool dump_core, void* siginfo, const void* context) {
1071 os::shutdown();
1072 if (dump_core) {
1073 ::abort(); // dump core
1074 }
1075
1076 ::exit(1);
1077 }
1078
1079 // Die immediately, no exit hook, no abort hook, no cleanup.
1080 // Dump a core file, if possible, for debugging.
1081 void os::die() {
1082 if (TestUnresponsiveErrorHandler && !CreateCoredumpOnCrash) {
1083 // For TimeoutInErrorHandlingTest.java, we just kill the VM
1084 // and don't take the time to generate a core file.
1085 os::signal_raise(SIGKILL);
1086 } else {
1087 // _exit() on BsdThreads only kills current thread
1088 ::abort();
1089 }
1090 }
1091
1092 // Information of current thread in variety of formats
1093 pid_t os::Bsd::gettid() {
1094 int retval = -1;
1095
1096 #ifdef __APPLE__ // XNU kernel
1097 mach_port_t port = mach_thread_self();
1098 guarantee(MACH_PORT_VALID(port), "just checking");
1099 mach_port_deallocate(mach_task_self(), port);
1100 return (pid_t)port;
1101
1102 #else
1103 #ifdef __FreeBSD__
1104 retval = syscall(SYS_thr_self);
1105 #else
1106 #ifdef __OpenBSD__
1107 retval = syscall(SYS_getthrid);
1108 #else
1109 #ifdef __NetBSD__
1110 retval = (pid_t) syscall(SYS__lwp_self);
1111 #endif
1112 #endif
1113 #endif
1114 #endif
1115
1116 if (retval == -1) {
1117 return getpid();
1118 }
1119 }
1120
1121 intx os::current_thread_id() {
1122 #ifdef __APPLE__
1123 return (intx)os::Bsd::gettid();
1124 #else
1125 return (intx)::pthread_self();
1126 #endif
1127 }
1128
1129 int os::current_process_id() {
1130 return (int)(getpid());
1131 }
1132
1133 // DLL functions
1134
1135 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1136
1137 // This must be hard coded because it's the system's temporary
1138 // directory not the java application's temp directory, ala java.io.tmpdir.
1139 #ifdef __APPLE__
1140 // macosx has a secure per-user temporary directory
1141 char temp_path_storage[PATH_MAX];
1142 const char* os::get_temp_directory() {
1143 static char *temp_path = NULL;
1144 if (temp_path == NULL) {
1145 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
1146 if (pathSize == 0 || pathSize > PATH_MAX) {
1147 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
1148 }
1149 temp_path = temp_path_storage;
1150 }
1151 return temp_path;
1152 }
1153 #else // __APPLE__
1154 const char* os::get_temp_directory() { return "/tmp"; }
1155 #endif // __APPLE__
1156
1157 // check if addr is inside libjvm.so
1158 bool os::address_is_in_vm(address addr) {
1159 static address libjvm_base_addr;
1160 Dl_info dlinfo;
1161
1162 if (libjvm_base_addr == NULL) {
1163 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) {
1164 libjvm_base_addr = (address)dlinfo.dli_fbase;
1165 }
1166 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1167 }
1168
1169 if (dladdr((void *)addr, &dlinfo) != 0) {
1170 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1171 }
1172
1173 return false;
1174 }
1175
1176
1177 #define MACH_MAXSYMLEN 256
1178
1179 bool os::dll_address_to_function_name(address addr, char *buf,
1180 int buflen, int *offset,
1181 bool demangle) {
1182 // buf is not optional, but offset is optional
1183 assert(buf != NULL, "sanity check");
1184
1185 Dl_info dlinfo;
1186 char localbuf[MACH_MAXSYMLEN];
1187
1188 if (dladdr((void*)addr, &dlinfo) != 0) {
1189 // see if we have a matching symbol
1190 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) {
1191 if (!(demangle && Decoder::demangle(dlinfo.dli_sname, buf, buflen))) {
1192 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1193 }
1194 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1195 return true;
1196 }
1197 // no matching symbol so try for just file info
1198 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) {
1199 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1200 buf, buflen, offset, dlinfo.dli_fname, demangle)) {
1201 return true;
1202 }
1203 }
1204
1205 // Handle non-dynamic manually:
1206 if (dlinfo.dli_fbase != NULL &&
1207 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset,
1208 dlinfo.dli_fbase)) {
1209 if (!(demangle && Decoder::demangle(localbuf, buf, buflen))) {
1210 jio_snprintf(buf, buflen, "%s", localbuf);
1211 }
1212 return true;
1213 }
1214 }
1215 buf[0] = '\0';
1216 if (offset != NULL) *offset = -1;
1217 return false;
1218 }
1219
1220 // ported from solaris version
1221 bool os::dll_address_to_library_name(address addr, char* buf,
1222 int buflen, int* offset) {
1223 // buf is not optional, but offset is optional
1224 assert(buf != NULL, "sanity check");
1225
1226 Dl_info dlinfo;
1227
1228 if (dladdr((void*)addr, &dlinfo) != 0) {
1229 if (dlinfo.dli_fname != NULL) {
1230 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1231 }
1232 if (dlinfo.dli_fbase != NULL && offset != NULL) {
1233 *offset = addr - (address)dlinfo.dli_fbase;
1234 }
1235 return true;
1236 }
1237
1238 buf[0] = '\0';
1239 if (offset) *offset = -1;
1240 return false;
1241 }
1242
1243 // Loads .dll/.so and
1244 // in case of error it checks if .dll/.so was built for the
1245 // same architecture as Hotspot is running on
1246
1247 #ifdef __APPLE__
1248 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1249 #ifdef STATIC_BUILD
1250 return os::get_default_process_handle();
1251 #else
1252 log_info(os)("attempting shared library load of %s", filename);
1253
1254 void * result= ::dlopen(filename, RTLD_LAZY);
1255 if (result != NULL) {
1256 Events::log(NULL, "Loaded shared library %s", filename);
1257 // Successful loading
1258 log_info(os)("shared library load of %s was successful", filename);
1259 return result;
1260 }
1261
1262 const char* error_report = ::dlerror();
1263 if (error_report == NULL) {
1264 error_report = "dlerror returned no error description";
1265 }
1266 if (ebuf != NULL && ebuflen > 0) {
1267 // Read system error message into ebuf
1268 ::strncpy(ebuf, error_report, ebuflen-1);
1269 ebuf[ebuflen-1]='\0';
1270 }
1271 Events::log(NULL, "Loading shared library %s failed, %s", filename, error_report);
1272 log_info(os)("shared library load of %s failed, %s", filename, error_report);
1273
1274 return NULL;
1275 #endif // STATIC_BUILD
1276 }
1277 #else
1278 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1279 #ifdef STATIC_BUILD
1280 return os::get_default_process_handle();
1281 #else
1282 log_info(os)("attempting shared library load of %s", filename);
1283 void * result= ::dlopen(filename, RTLD_LAZY);
1284 if (result != NULL) {
1285 Events::log(NULL, "Loaded shared library %s", filename);
1286 // Successful loading
1287 log_info(os)("shared library load of %s was successful", filename);
1288 return result;
1289 }
1290
1291 Elf32_Ehdr elf_head;
1292
1293 const char* const error_report = ::dlerror();
1294 if (error_report == NULL) {
1295 error_report = "dlerror returned no error description";
1296 }
1297 if (ebuf != NULL && ebuflen > 0) {
1298 // Read system error message into ebuf
1299 ::strncpy(ebuf, error_report, ebuflen-1);
1300 ebuf[ebuflen-1]='\0';
1301 }
1302 Events::log(NULL, "Loading shared library %s failed, %s", filename, error_report);
1303 log_info(os)("shared library load of %s failed, %s", filename, error_report);
1304
1305 int diag_msg_max_length=ebuflen-strlen(ebuf);
1306 char* diag_msg_buf=ebuf+strlen(ebuf);
1307
1308 if (diag_msg_max_length==0) {
1309 // No more space in ebuf for additional diagnostics message
1310 return NULL;
1311 }
1312
1313
1314 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1315
1316 if (file_descriptor < 0) {
1317 // Can't open library, report dlerror() message
1318 return NULL;
1319 }
1320
1321 bool failed_to_read_elf_head=
1322 (sizeof(elf_head)!=
1323 (::read(file_descriptor, &elf_head,sizeof(elf_head))));
1324
1325 ::close(file_descriptor);
1326 if (failed_to_read_elf_head) {
1327 // file i/o error - report dlerror() msg
1328 return NULL;
1329 }
1330
1331 typedef struct {
1332 Elf32_Half code; // Actual value as defined in elf.h
1333 Elf32_Half compat_class; // Compatibility of archs at VM's sense
1334 char elf_class; // 32 or 64 bit
1335 char endianess; // MSB or LSB
1336 char* name; // String representation
1337 } arch_t;
1338
1339 #ifndef EM_486
1340 #define EM_486 6 /* Intel 80486 */
1341 #endif
1342
1343 #ifndef EM_MIPS_RS3_LE
1344 #define EM_MIPS_RS3_LE 10 /* MIPS */
1345 #endif
1346
1347 #ifndef EM_PPC64
1348 #define EM_PPC64 21 /* PowerPC64 */
1349 #endif
1350
1351 #ifndef EM_S390
1352 #define EM_S390 22 /* IBM System/390 */
1353 #endif
1354
1355 #ifndef EM_IA_64
1356 #define EM_IA_64 50 /* HP/Intel IA-64 */
1357 #endif
1358
1359 #ifndef EM_X86_64
1360 #define EM_X86_64 62 /* AMD x86-64 */
1361 #endif
1362
1363 static const arch_t arch_array[]={
1364 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1365 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1366 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
1367 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
1368 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1369 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1370 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
1371 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
1372 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
1373 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"},
1374 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
1375 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
1376 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
1377 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
1378 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
1379 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
1380 };
1381
1382 #if (defined IA32)
1383 static Elf32_Half running_arch_code=EM_386;
1384 #elif (defined AMD64)
1385 static Elf32_Half running_arch_code=EM_X86_64;
1386 #elif (defined IA64)
1387 static Elf32_Half running_arch_code=EM_IA_64;
1388 #elif (defined __sparc) && (defined _LP64)
1389 static Elf32_Half running_arch_code=EM_SPARCV9;
1390 #elif (defined __sparc) && (!defined _LP64)
1391 static Elf32_Half running_arch_code=EM_SPARC;
1392 #elif (defined __powerpc64__)
1393 static Elf32_Half running_arch_code=EM_PPC64;
1394 #elif (defined __powerpc__)
1395 static Elf32_Half running_arch_code=EM_PPC;
1396 #elif (defined ARM)
1397 static Elf32_Half running_arch_code=EM_ARM;
1398 #elif (defined S390)
1399 static Elf32_Half running_arch_code=EM_S390;
1400 #elif (defined ALPHA)
1401 static Elf32_Half running_arch_code=EM_ALPHA;
1402 #elif (defined MIPSEL)
1403 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
1404 #elif (defined PARISC)
1405 static Elf32_Half running_arch_code=EM_PARISC;
1406 #elif (defined MIPS)
1407 static Elf32_Half running_arch_code=EM_MIPS;
1408 #elif (defined M68K)
1409 static Elf32_Half running_arch_code=EM_68K;
1410 #else
1411 #error Method os::dll_load requires that one of following is defined:\
1412 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
1413 #endif
1414
1415 // Identify compatability class for VM's architecture and library's architecture
1416 // Obtain string descriptions for architectures
1417
1418 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
1419 int running_arch_index=-1;
1420
1421 for (unsigned int i=0; i < ARRAY_SIZE(arch_array); i++) {
1422 if (running_arch_code == arch_array[i].code) {
1423 running_arch_index = i;
1424 }
1425 if (lib_arch.code == arch_array[i].code) {
1426 lib_arch.compat_class = arch_array[i].compat_class;
1427 lib_arch.name = arch_array[i].name;
1428 }
1429 }
1430
1431 assert(running_arch_index != -1,
1432 "Didn't find running architecture code (running_arch_code) in arch_array");
1433 if (running_arch_index == -1) {
1434 // Even though running architecture detection failed
1435 // we may still continue with reporting dlerror() message
1436 return NULL;
1437 }
1438
1439 if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
1440 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
1441 return NULL;
1442 }
1443
1444 #ifndef S390
1445 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
1446 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
1447 return NULL;
1448 }
1449 #endif // !S390
1450
1451 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
1452 if (lib_arch.name!=NULL) {
1453 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1454 " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
1455 lib_arch.name, arch_array[running_arch_index].name);
1456 } else {
1457 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1458 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
1459 lib_arch.code,
1460 arch_array[running_arch_index].name);
1461 }
1462 }
1463
1464 return NULL;
1465 #endif // STATIC_BUILD
1466 }
1467 #endif // !__APPLE__
1468
1469 void* os::get_default_process_handle() {
1470 #ifdef __APPLE__
1471 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY
1472 // to avoid finding unexpected symbols on second (or later)
1473 // loads of a library.
1474 return (void*)::dlopen(NULL, RTLD_FIRST);
1475 #else
1476 return (void*)::dlopen(NULL, RTLD_LAZY);
1477 #endif
1478 }
1479
1480 // XXX: Do we need a lock around this as per Linux?
1481 void* os::dll_lookup(void* handle, const char* name) {
1482 return dlsym(handle, name);
1483 }
1484
1485 int _print_dll_info_cb(const char * name, address base_address, address top_address, void * param) {
1486 outputStream * out = (outputStream *) param;
1487 out->print_cr(INTPTR_FORMAT " \t%s", (intptr_t)base_address, name);
1488 return 0;
1489 }
1490
1491 void os::print_dll_info(outputStream *st) {
1492 st->print_cr("Dynamic libraries:");
1493 if (get_loaded_modules_info(_print_dll_info_cb, (void *)st)) {
1494 st->print_cr("Error: Cannot print dynamic libraries.");
1495 }
1496 }
1497
1498 int os::get_loaded_modules_info(os::LoadedModulesCallbackFunc callback, void *param) {
1499 #ifdef RTLD_DI_LINKMAP
1500 Dl_info dli;
1501 void *handle;
1502 Link_map *map;
1503 Link_map *p;
1504
1505 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 ||
1506 dli.dli_fname == NULL) {
1507 return 1;
1508 }
1509 handle = dlopen(dli.dli_fname, RTLD_LAZY);
1510 if (handle == NULL) {
1511 return 1;
1512 }
1513 dlinfo(handle, RTLD_DI_LINKMAP, &map);
1514 if (map == NULL) {
1515 dlclose(handle);
1516 return 1;
1517 }
1518
1519 while (map->l_prev != NULL)
1520 map = map->l_prev;
1521
1522 while (map != NULL) {
1523 // Value for top_address is returned as 0 since we don't have any information about module size
1524 if (callback(map->l_name, (address)map->l_addr, (address)0, param)) {
1525 dlclose(handle);
1526 return 1;
1527 }
1528 map = map->l_next;
1529 }
1530
1531 dlclose(handle);
1532 #elif defined(__APPLE__)
1533 for (uint32_t i = 1; i < _dyld_image_count(); i++) {
1534 // Value for top_address is returned as 0 since we don't have any information about module size
1535 if (callback(_dyld_get_image_name(i), (address)_dyld_get_image_header(i), (address)0, param)) {
1536 return 1;
1537 }
1538 }
1539 return 0;
1540 #else
1541 return 1;
1542 #endif
1543 }
1544
1545 void os::get_summary_os_info(char* buf, size_t buflen) {
1546 // These buffers are small because we want this to be brief
1547 // and not use a lot of stack while generating the hs_err file.
1548 char os[100];
1549 size_t size = sizeof(os);
1550 int mib_kern[] = { CTL_KERN, KERN_OSTYPE };
1551 if (sysctl(mib_kern, 2, os, &size, NULL, 0) < 0) {
1552 #ifdef __APPLE__
1553 strncpy(os, "Darwin", sizeof(os));
1554 #elif __OpenBSD__
1555 strncpy(os, "OpenBSD", sizeof(os));
1556 #else
1557 strncpy(os, "BSD", sizeof(os));
1558 #endif
1559 }
1560
1561 char release[100];
1562 size = sizeof(release);
1563 int mib_release[] = { CTL_KERN, KERN_OSRELEASE };
1564 if (sysctl(mib_release, 2, release, &size, NULL, 0) < 0) {
1565 // if error, leave blank
1566 strncpy(release, "", sizeof(release));
1567 }
1568 snprintf(buf, buflen, "%s %s", os, release);
1569 }
1570
1571 void os::print_os_info_brief(outputStream* st) {
1572 os::Posix::print_uname_info(st);
1573 }
1574
1575 void os::print_os_info(outputStream* st) {
1576 st->print("OS:");
1577
1578 os::Posix::print_uname_info(st);
1579
1580 os::Bsd::print_uptime_info(st);
1581
1582 os::Posix::print_rlimit_info(st);
1583
1584 os::Posix::print_load_average(st);
1585
1586 VM_Version::print_platform_virtualization_info(st);
1587 }
1588
1589 void os::pd_print_cpu_info(outputStream* st, char* buf, size_t buflen) {
1590 // Nothing to do for now.
1591 }
1592
1593 void os::get_summary_cpu_info(char* buf, size_t buflen) {
1594 unsigned int mhz;
1595 size_t size = sizeof(mhz);
1596 int mib[] = { CTL_HW, HW_CPU_FREQ };
1597 if (sysctl(mib, 2, &mhz, &size, NULL, 0) < 0) {
1598 mhz = 1; // looks like an error but can be divided by
1599 } else {
1600 mhz /= 1000000; // reported in millions
1601 }
1602
1603 char model[100];
1604 size = sizeof(model);
1605 int mib_model[] = { CTL_HW, HW_MODEL };
1606 if (sysctl(mib_model, 2, model, &size, NULL, 0) < 0) {
1607 strncpy(model, cpu_arch, sizeof(model));
1608 }
1609
1610 char machine[100];
1611 size = sizeof(machine);
1612 int mib_machine[] = { CTL_HW, HW_MACHINE };
1613 if (sysctl(mib_machine, 2, machine, &size, NULL, 0) < 0) {
1614 strncpy(machine, "", sizeof(machine));
1615 }
1616
1617 snprintf(buf, buflen, "%s %s %d MHz", model, machine, mhz);
1618 }
1619
1620 void os::print_memory_info(outputStream* st) {
1621 xsw_usage swap_usage;
1622 size_t size = sizeof(swap_usage);
1623
1624 st->print("Memory:");
1625 st->print(" %dk page", os::vm_page_size()>>10);
1626
1627 st->print(", physical " UINT64_FORMAT "k",
1628 os::physical_memory() >> 10);
1629 st->print("(" UINT64_FORMAT "k free)",
1630 os::available_memory() >> 10);
1631
1632 if((sysctlbyname("vm.swapusage", &swap_usage, &size, NULL, 0) == 0) || (errno == ENOMEM)) {
1633 if (size >= offset_of(xsw_usage, xsu_used)) {
1634 st->print(", swap " UINT64_FORMAT "k",
1635 ((julong) swap_usage.xsu_total) >> 10);
1636 st->print("(" UINT64_FORMAT "k free)",
1637 ((julong) swap_usage.xsu_avail) >> 10);
1638 }
1639 }
1640
1641 st->cr();
1642 }
1643
1644 static void print_signal_handler(outputStream* st, int sig,
1645 char* buf, size_t buflen);
1646
1647 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1648 st->print_cr("Signal Handlers:");
1649 print_signal_handler(st, SIGSEGV, buf, buflen);
1650 print_signal_handler(st, SIGBUS , buf, buflen);
1651 print_signal_handler(st, SIGFPE , buf, buflen);
1652 print_signal_handler(st, SIGPIPE, buf, buflen);
1653 print_signal_handler(st, SIGXFSZ, buf, buflen);
1654 print_signal_handler(st, SIGILL , buf, buflen);
1655 print_signal_handler(st, SR_signum, buf, buflen);
1656 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1657 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1658 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1659 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1660 }
1661
1662 static char saved_jvm_path[MAXPATHLEN] = {0};
1663
1664 // Find the full path to the current module, libjvm
1665 void os::jvm_path(char *buf, jint buflen) {
1666 // Error checking.
1667 if (buflen < MAXPATHLEN) {
1668 assert(false, "must use a large-enough buffer");
1669 buf[0] = '\0';
1670 return;
1671 }
1672 // Lazy resolve the path to current module.
1673 if (saved_jvm_path[0] != 0) {
1674 strcpy(buf, saved_jvm_path);
1675 return;
1676 }
1677
1678 char dli_fname[MAXPATHLEN];
1679 bool ret = dll_address_to_library_name(
1680 CAST_FROM_FN_PTR(address, os::jvm_path),
1681 dli_fname, sizeof(dli_fname), NULL);
1682 assert(ret, "cannot locate libjvm");
1683 char *rp = NULL;
1684 if (ret && dli_fname[0] != '\0') {
1685 rp = os::Posix::realpath(dli_fname, buf, buflen);
1686 }
1687 if (rp == NULL) {
1688 return;
1689 }
1690
1691 if (Arguments::sun_java_launcher_is_altjvm()) {
1692 // Support for the java launcher's '-XXaltjvm=<path>' option. Typical
1693 // value for buf is "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so"
1694 // or "<JAVA_HOME>/jre/lib/<vmtype>/libjvm.dylib". If "/jre/lib/"
1695 // appears at the right place in the string, then assume we are
1696 // installed in a JDK and we're done. Otherwise, check for a
1697 // JAVA_HOME environment variable and construct a path to the JVM
1698 // being overridden.
1699
1700 const char *p = buf + strlen(buf) - 1;
1701 for (int count = 0; p > buf && count < 5; ++count) {
1702 for (--p; p > buf && *p != '/'; --p)
1703 /* empty */ ;
1704 }
1705
1706 if (strncmp(p, "/jre/lib/", 9) != 0) {
1707 // Look for JAVA_HOME in the environment.
1708 char* java_home_var = ::getenv("JAVA_HOME");
1709 if (java_home_var != NULL && java_home_var[0] != 0) {
1710 char* jrelib_p;
1711 int len;
1712
1713 // Check the current module name "libjvm"
1714 p = strrchr(buf, '/');
1715 assert(strstr(p, "/libjvm") == p, "invalid library name");
1716
1717 rp = os::Posix::realpath(java_home_var, buf, buflen);
1718 if (rp == NULL) {
1719 return;
1720 }
1721
1722 // determine if this is a legacy image or modules image
1723 // modules image doesn't have "jre" subdirectory
1724 len = strlen(buf);
1725 assert(len < buflen, "Ran out of buffer space");
1726 jrelib_p = buf + len;
1727
1728 // Add the appropriate library subdir
1729 snprintf(jrelib_p, buflen-len, "/jre/lib");
1730 if (0 != access(buf, F_OK)) {
1731 snprintf(jrelib_p, buflen-len, "/lib");
1732 }
1733
1734 // Add the appropriate client or server subdir
1735 len = strlen(buf);
1736 jrelib_p = buf + len;
1737 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
1738 if (0 != access(buf, F_OK)) {
1739 snprintf(jrelib_p, buflen-len, "%s", "");
1740 }
1741
1742 // If the path exists within JAVA_HOME, add the JVM library name
1743 // to complete the path to JVM being overridden. Otherwise fallback
1744 // to the path to the current library.
1745 if (0 == access(buf, F_OK)) {
1746 // Use current module name "libjvm"
1747 len = strlen(buf);
1748 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
1749 } else {
1750 // Fall back to path of current library
1751 rp = os::Posix::realpath(dli_fname, buf, buflen);
1752 if (rp == NULL) {
1753 return;
1754 }
1755 }
1756 }
1757 }
1758 }
1759
1760 strncpy(saved_jvm_path, buf, MAXPATHLEN);
1761 saved_jvm_path[MAXPATHLEN - 1] = '\0';
1762 }
1763
1764 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1765 // no prefix required, not even "_"
1766 }
1767
1768 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1769 // no suffix required
1770 }
1771
1772 ////////////////////////////////////////////////////////////////////////////////
1773 // sun.misc.Signal support
1774
1775 static void UserHandler(int sig, void *siginfo, void *context) {
1776 // Ctrl-C is pressed during error reporting, likely because the error
1777 // handler fails to abort. Let VM die immediately.
1778 if (sig == SIGINT && VMError::is_error_reported()) {
1779 os::die();
1780 }
1781
1782 os::signal_notify(sig);
1783 }
1784
1785 void* os::user_handler() {
1786 return CAST_FROM_FN_PTR(void*, UserHandler);
1787 }
1788
1789 extern "C" {
1790 typedef void (*sa_handler_t)(int);
1791 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1792 }
1793
1794 void* os::signal(int signal_number, void* handler) {
1795 struct sigaction sigAct, oldSigAct;
1796
1797 sigfillset(&(sigAct.sa_mask));
1798 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
1799 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1800
1801 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1802 // -1 means registration failed
1803 return (void *)-1;
1804 }
1805
1806 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1807 }
1808
1809 void os::signal_raise(int signal_number) {
1810 ::raise(signal_number);
1811 }
1812
1813 // The following code is moved from os.cpp for making this
1814 // code platform specific, which it is by its very nature.
1815
1816 // Will be modified when max signal is changed to be dynamic
1817 int os::sigexitnum_pd() {
1818 return NSIG;
1819 }
1820
1821 // a counter for each possible signal value
1822 static volatile jint pending_signals[NSIG+1] = { 0 };
1823 static Semaphore* sig_sem = NULL;
1824
1825 static void jdk_misc_signal_init() {
1826 // Initialize signal structures
1827 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
1828
1829 // Initialize signal semaphore
1830 sig_sem = new Semaphore();
1831 }
1832
1833 void os::signal_notify(int sig) {
1834 if (sig_sem != NULL) {
1835 Atomic::inc(&pending_signals[sig]);
1836 sig_sem->signal();
1837 } else {
1838 // Signal thread is not created with ReduceSignalUsage and jdk_misc_signal_init
1839 // initialization isn't called.
1840 assert(ReduceSignalUsage, "signal semaphore should be created");
1841 }
1842 }
1843
1844 static int check_pending_signals() {
1845 for (;;) {
1846 for (int i = 0; i < NSIG + 1; i++) {
1847 jint n = pending_signals[i];
1848 if (n > 0 && n == Atomic::cmpxchg(&pending_signals[i], n, n - 1)) {
1849 return i;
1850 }
1851 }
1852 JavaThread *thread = JavaThread::current();
1853 ThreadBlockInVM tbivm(thread);
1854
1855 bool threadIsSuspended;
1856 do {
1857 thread->set_suspend_equivalent();
1858 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
1859 sig_sem->wait();
1860
1861 // were we externally suspended while we were waiting?
1862 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
1863 if (threadIsSuspended) {
1864 // The semaphore has been incremented, but while we were waiting
1865 // another thread suspended us. We don't want to continue running
1866 // while suspended because that would surprise the thread that
1867 // suspended us.
1868 sig_sem->signal();
1869
1870 thread->java_suspend_self();
1871 }
1872 } while (threadIsSuspended);
1873 }
1874 }
1875
1876 int os::signal_wait() {
1877 return check_pending_signals();
1878 }
1879
1880 ////////////////////////////////////////////////////////////////////////////////
1881 // Virtual Memory
1882
1883 int os::vm_page_size() {
1884 // Seems redundant as all get out
1885 assert(os::Bsd::page_size() != -1, "must call os::init");
1886 return os::Bsd::page_size();
1887 }
1888
1889 // Solaris allocates memory by pages.
1890 int os::vm_allocation_granularity() {
1891 assert(os::Bsd::page_size() != -1, "must call os::init");
1892 return os::Bsd::page_size();
1893 }
1894
1895 // Rationale behind this function:
1896 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
1897 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
1898 // samples for JITted code. Here we create private executable mapping over the code cache
1899 // and then we can use standard (well, almost, as mapping can change) way to provide
1900 // info for the reporting script by storing timestamp and location of symbol
1901 void bsd_wrap_code(char* base, size_t size) {
1902 static volatile jint cnt = 0;
1903
1904 if (!UseOprofile) {
1905 return;
1906 }
1907
1908 char buf[PATH_MAX + 1];
1909 int num = Atomic::add(&cnt, 1);
1910
1911 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
1912 os::get_temp_directory(), os::current_process_id(), num);
1913 unlink(buf);
1914
1915 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
1916
1917 if (fd != -1) {
1918 off_t rv = ::lseek(fd, size-2, SEEK_SET);
1919 if (rv != (off_t)-1) {
1920 if (::write(fd, "", 1) == 1) {
1921 mmap(base, size,
1922 PROT_READ|PROT_WRITE|PROT_EXEC,
1923 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
1924 }
1925 }
1926 ::close(fd);
1927 unlink(buf);
1928 }
1929 }
1930
1931 static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
1932 int err) {
1933 warning("INFO: os::commit_memory(" INTPTR_FORMAT ", " SIZE_FORMAT
1934 ", %d) failed; error='%s' (errno=%d)", (intptr_t)addr, size, exec,
1935 os::errno_name(err), err);
1936 }
1937
1938 // NOTE: Bsd kernel does not really reserve the pages for us.
1939 // All it does is to check if there are enough free pages
1940 // left at the time of mmap(). This could be a potential
1941 // problem.
1942 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
1943 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
1944 #ifdef __OpenBSD__
1945 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
1946 Events::log(NULL, "Protecting memory [" INTPTR_FORMAT "," INTPTR_FORMAT "] with protection modes %x", p2i(addr), p2i(addr+size), prot);
1947 if (::mprotect(addr, size, prot) == 0) {
1948 return true;
1949 }
1950 #else
1951 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
1952 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
1953 if (res != (uintptr_t) MAP_FAILED) {
1954 return true;
1955 }
1956 #endif
1957
1958 // Warn about any commit errors we see in non-product builds just
1959 // in case mmap() doesn't work as described on the man page.
1960 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);)
1961
1962 return false;
1963 }
1964
1965 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
1966 bool exec) {
1967 // alignment_hint is ignored on this OS
1968 return pd_commit_memory(addr, size, exec);
1969 }
1970
1971 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
1972 const char* mesg) {
1973 assert(mesg != NULL, "mesg must be specified");
1974 if (!pd_commit_memory(addr, size, exec)) {
1975 // add extra info in product mode for vm_exit_out_of_memory():
1976 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
1977 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, "%s", mesg);
1978 }
1979 }
1980
1981 void os::pd_commit_memory_or_exit(char* addr, size_t size,
1982 size_t alignment_hint, bool exec,
1983 const char* mesg) {
1984 // alignment_hint is ignored on this OS
1985 pd_commit_memory_or_exit(addr, size, exec, mesg);
1986 }
1987
1988 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
1989 }
1990
1991 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
1992 ::madvise(addr, bytes, MADV_DONTNEED);
1993 }
1994
1995 void os::numa_make_global(char *addr, size_t bytes) {
1996 }
1997
1998 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
1999 }
2000
2001 bool os::numa_topology_changed() { return false; }
2002
2003 size_t os::numa_get_groups_num() {
2004 return 1;
2005 }
2006
2007 int os::numa_get_group_id() {
2008 return 0;
2009 }
2010
2011 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
2012 if (size > 0) {
2013 ids[0] = 0;
2014 return 1;
2015 }
2016 return 0;
2017 }
2018
2019 int os::numa_get_group_id_for_address(const void* address) {
2020 return 0;
2021 }
2022
2023 bool os::get_page_info(char *start, page_info* info) {
2024 return false;
2025 }
2026
2027 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2028 return end;
2029 }
2030
2031
2032 bool os::pd_uncommit_memory(char* addr, size_t size) {
2033 #ifdef __OpenBSD__
2034 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2035 Events::log(NULL, "Protecting memory [" INTPTR_FORMAT "," INTPTR_FORMAT "] with PROT_NONE", p2i(addr), p2i(addr+size));
2036 return ::mprotect(addr, size, PROT_NONE) == 0;
2037 #else
2038 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
2039 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
2040 return res != (uintptr_t) MAP_FAILED;
2041 #endif
2042 }
2043
2044 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2045 return os::commit_memory(addr, size, !ExecMem);
2046 }
2047
2048 // If this is a growable mapping, remove the guard pages entirely by
2049 // munmap()ping them. If not, just call uncommit_memory().
2050 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2051 return os::uncommit_memory(addr, size);
2052 }
2053
2054 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2055 // at 'requested_addr'. If there are existing memory mappings at the same
2056 // location, however, they will be overwritten. If 'fixed' is false,
2057 // 'requested_addr' is only treated as a hint, the return value may or
2058 // may not start from the requested address. Unlike Bsd mmap(), this
2059 // function returns NULL to indicate failure.
2060 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2061 char * addr;
2062 int flags;
2063
2064 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2065 if (fixed) {
2066 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2067 flags |= MAP_FIXED;
2068 }
2069
2070 // Map reserved/uncommitted pages PROT_NONE so we fail early if we
2071 // touch an uncommitted page. Otherwise, the read/write might
2072 // succeed if we have enough swap space to back the physical page.
2073 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE,
2074 flags, -1, 0);
2075
2076 return addr == MAP_FAILED ? NULL : addr;
2077 }
2078
2079 static int anon_munmap(char * addr, size_t size) {
2080 return ::munmap(addr, size) == 0;
2081 }
2082
2083 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
2084 size_t alignment_hint) {
2085 return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2086 }
2087
2088 bool os::pd_release_memory(char* addr, size_t size) {
2089 return anon_munmap(addr, size);
2090 }
2091
2092 static bool bsd_mprotect(char* addr, size_t size, int prot) {
2093 // Bsd wants the mprotect address argument to be page aligned.
2094 char* bottom = (char*)align_down((intptr_t)addr, os::Bsd::page_size());
2095
2096 // According to SUSv3, mprotect() should only be used with mappings
2097 // established by mmap(), and mmap() always maps whole pages. Unaligned
2098 // 'addr' likely indicates problem in the VM (e.g. trying to change
2099 // protection of malloc'ed or statically allocated memory). Check the
2100 // caller if you hit this assert.
2101 assert(addr == bottom, "sanity check");
2102
2103 size = align_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2104 Events::log(NULL, "Protecting memory [" INTPTR_FORMAT "," INTPTR_FORMAT "] with protection modes %x", p2i(bottom), p2i(bottom+size), prot);
2105 return ::mprotect(bottom, size, prot) == 0;
2106 }
2107
2108 // Set protections specified
2109 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2110 bool is_committed) {
2111 unsigned int p = 0;
2112 switch (prot) {
2113 case MEM_PROT_NONE: p = PROT_NONE; break;
2114 case MEM_PROT_READ: p = PROT_READ; break;
2115 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
2116 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2117 default:
2118 ShouldNotReachHere();
2119 }
2120 // is_committed is unused.
2121 return bsd_mprotect(addr, bytes, p);
2122 }
2123
2124 bool os::guard_memory(char* addr, size_t size) {
2125 return bsd_mprotect(addr, size, PROT_NONE);
2126 }
2127
2128 bool os::unguard_memory(char* addr, size_t size) {
2129 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
2130 }
2131
2132 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
2133 return false;
2134 }
2135
2136 // Large page support
2137
2138 static size_t _large_page_size = 0;
2139
2140 void os::large_page_init() {
2141 }
2142
2143
2144 char* os::pd_reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) {
2145 fatal("os::reserve_memory_special should not be called on BSD.");
2146 return NULL;
2147 }
2148
2149 bool os::pd_release_memory_special(char* base, size_t bytes) {
2150 fatal("os::release_memory_special should not be called on BSD.");
2151 return false;
2152 }
2153
2154 size_t os::large_page_size() {
2155 return _large_page_size;
2156 }
2157
2158 bool os::can_commit_large_page_memory() {
2159 // Does not matter, we do not support huge pages.
2160 return false;
2161 }
2162
2163 bool os::can_execute_large_page_memory() {
2164 // Does not matter, we do not support huge pages.
2165 return false;
2166 }
2167
2168 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr, int file_desc) {
2169 assert(file_desc >= 0, "file_desc is not valid");
2170 char* result = pd_attempt_reserve_memory_at(bytes, requested_addr);
2171 if (result != NULL) {
2172 if (replace_existing_mapping_with_file_mapping(result, bytes, file_desc) == NULL) {
2173 vm_exit_during_initialization(err_msg("Error in mapping Java heap at the given filesystem directory"));
2174 }
2175 }
2176 return result;
2177 }
2178
2179 // Reserve memory at an arbitrary address, only if that area is
2180 // available (and not reserved for something else).
2181
2182 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2183 // Assert only that the size is a multiple of the page size, since
2184 // that's all that mmap requires, and since that's all we really know
2185 // about at this low abstraction level. If we need higher alignment,
2186 // we can either pass an alignment to this method or verify alignment
2187 // in one of the methods further up the call chain. See bug 5044738.
2188 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2189
2190 // Repeatedly allocate blocks until the block is allocated at the
2191 // right spot.
2192
2193 // Bsd mmap allows caller to pass an address as hint; give it a try first,
2194 // if kernel honors the hint then we can return immediately.
2195 char * addr = anon_mmap(requested_addr, bytes, false);
2196 if (addr == requested_addr) {
2197 return requested_addr;
2198 }
2199
2200 if (addr != NULL) {
2201 // mmap() is successful but it fails to reserve at the requested address
2202 anon_munmap(addr, bytes);
2203 }
2204
2205 return NULL;
2206 }
2207
2208 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2209 void os::infinite_sleep() {
2210 while (true) { // sleep forever ...
2211 ::sleep(100); // ... 100 seconds at a time
2212 }
2213 }
2214
2215 // Used to convert frequent JVM_Yield() to nops
2216 bool os::dont_yield() {
2217 return DontYieldALot;
2218 }
2219
2220 void os::naked_yield() {
2221 sched_yield();
2222 }
2223
2224 ////////////////////////////////////////////////////////////////////////////////
2225 // thread priority support
2226
2227 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2228 // only supports dynamic priority, static priority must be zero. For real-time
2229 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
2230 // However, for large multi-threaded applications, SCHED_RR is not only slower
2231 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2232 // of 5 runs - Sep 2005).
2233 //
2234 // The following code actually changes the niceness of kernel-thread/LWP. It
2235 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
2236 // not the entire user process, and user level threads are 1:1 mapped to kernel
2237 // threads. It has always been the case, but could change in the future. For
2238 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2239 // It is only used when ThreadPriorityPolicy=1 and may require system level permission
2240 // (e.g., root privilege or CAP_SYS_NICE capability).
2241
2242 #if !defined(__APPLE__)
2243 int os::java_to_os_priority[CriticalPriority + 1] = {
2244 19, // 0 Entry should never be used
2245
2246 0, // 1 MinPriority
2247 3, // 2
2248 6, // 3
2249
2250 10, // 4
2251 15, // 5 NormPriority
2252 18, // 6
2253
2254 21, // 7
2255 25, // 8
2256 28, // 9 NearMaxPriority
2257
2258 31, // 10 MaxPriority
2259
2260 31 // 11 CriticalPriority
2261 };
2262 #else
2263 // Using Mach high-level priority assignments
2264 int os::java_to_os_priority[CriticalPriority + 1] = {
2265 0, // 0 Entry should never be used (MINPRI_USER)
2266
2267 27, // 1 MinPriority
2268 28, // 2
2269 29, // 3
2270
2271 30, // 4
2272 31, // 5 NormPriority (BASEPRI_DEFAULT)
2273 32, // 6
2274
2275 33, // 7
2276 34, // 8
2277 35, // 9 NearMaxPriority
2278
2279 36, // 10 MaxPriority
2280
2281 36 // 11 CriticalPriority
2282 };
2283 #endif
2284
2285 static int prio_init() {
2286 if (ThreadPriorityPolicy == 1) {
2287 if (geteuid() != 0) {
2288 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy) && !FLAG_IS_JIMAGE_RESOURCE(ThreadPriorityPolicy)) {
2289 warning("-XX:ThreadPriorityPolicy=1 may require system level permission, " \
2290 "e.g., being the root user. If the necessary permission is not " \
2291 "possessed, changes to priority will be silently ignored.");
2292 }
2293 }
2294 }
2295 if (UseCriticalJavaThreadPriority) {
2296 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2297 }
2298 return 0;
2299 }
2300
2301 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2302 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) return OS_OK;
2303
2304 #ifdef __OpenBSD__
2305 // OpenBSD pthread_setprio starves low priority threads
2306 return OS_OK;
2307 #elif defined(__FreeBSD__)
2308 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2309 return (ret == 0) ? OS_OK : OS_ERR;
2310 #elif defined(__APPLE__) || defined(__NetBSD__)
2311 struct sched_param sp;
2312 int policy;
2313
2314 if (pthread_getschedparam(thread->osthread()->pthread_id(), &policy, &sp) != 0) {
2315 return OS_ERR;
2316 }
2317
2318 sp.sched_priority = newpri;
2319 if (pthread_setschedparam(thread->osthread()->pthread_id(), policy, &sp) != 0) {
2320 return OS_ERR;
2321 }
2322
2323 return OS_OK;
2324 #else
2325 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2326 return (ret == 0) ? OS_OK : OS_ERR;
2327 #endif
2328 }
2329
2330 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2331 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) {
2332 *priority_ptr = java_to_os_priority[NormPriority];
2333 return OS_OK;
2334 }
2335
2336 errno = 0;
2337 #if defined(__OpenBSD__) || defined(__FreeBSD__)
2338 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2339 #elif defined(__APPLE__) || defined(__NetBSD__)
2340 int policy;
2341 struct sched_param sp;
2342
2343 int res = pthread_getschedparam(thread->osthread()->pthread_id(), &policy, &sp);
2344 if (res != 0) {
2345 *priority_ptr = -1;
2346 return OS_ERR;
2347 } else {
2348 *priority_ptr = sp.sched_priority;
2349 return OS_OK;
2350 }
2351 #else
2352 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2353 #endif
2354 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2355 }
2356
2357 ////////////////////////////////////////////////////////////////////////////////
2358 // suspend/resume support
2359
2360 // The low-level signal-based suspend/resume support is a remnant from the
2361 // old VM-suspension that used to be for java-suspension, safepoints etc,
2362 // within hotspot. Currently used by JFR's OSThreadSampler
2363 //
2364 // The remaining code is greatly simplified from the more general suspension
2365 // code that used to be used.
2366 //
2367 // The protocol is quite simple:
2368 // - suspend:
2369 // - sends a signal to the target thread
2370 // - polls the suspend state of the osthread using a yield loop
2371 // - target thread signal handler (SR_handler) sets suspend state
2372 // and blocks in sigsuspend until continued
2373 // - resume:
2374 // - sets target osthread state to continue
2375 // - sends signal to end the sigsuspend loop in the SR_handler
2376 //
2377 // Note that the SR_lock plays no role in this suspend/resume protocol,
2378 // but is checked for NULL in SR_handler as a thread termination indicator.
2379 // The SR_lock is, however, used by JavaThread::java_suspend()/java_resume() APIs.
2380 //
2381 // Note that resume_clear_context() and suspend_save_context() are needed
2382 // by SR_handler(), so that fetch_frame_from_ucontext() works,
2383 // which in part is used by:
2384 // - Forte Analyzer: AsyncGetCallTrace()
2385 // - StackBanging: get_frame_at_stack_banging_point()
2386
2387 static void resume_clear_context(OSThread *osthread) {
2388 osthread->set_ucontext(NULL);
2389 osthread->set_siginfo(NULL);
2390 }
2391
2392 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2393 osthread->set_ucontext(context);
2394 osthread->set_siginfo(siginfo);
2395 }
2396
2397 // Handler function invoked when a thread's execution is suspended or
2398 // resumed. We have to be careful that only async-safe functions are
2399 // called here (Note: most pthread functions are not async safe and
2400 // should be avoided.)
2401 //
2402 // Note: sigwait() is a more natural fit than sigsuspend() from an
2403 // interface point of view, but sigwait() prevents the signal hander
2404 // from being run. libpthread would get very confused by not having
2405 // its signal handlers run and prevents sigwait()'s use with the
2406 // mutex granting granting signal.
2407 //
2408 // Currently only ever called on the VMThread or JavaThread
2409 //
2410 #ifdef __APPLE__
2411 static OSXSemaphore sr_semaphore;
2412 #else
2413 static PosixSemaphore sr_semaphore;
2414 #endif
2415
2416 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2417 // Save and restore errno to avoid confusing native code with EINTR
2418 // after sigsuspend.
2419 int old_errno = errno;
2420
2421 Thread* thread = Thread::current_or_null_safe();
2422 assert(thread != NULL, "Missing current thread in SR_handler");
2423
2424 // On some systems we have seen signal delivery get "stuck" until the signal
2425 // mask is changed as part of thread termination. Check that the current thread
2426 // has not already terminated (via SR_lock()) - else the following assertion
2427 // will fail because the thread is no longer a JavaThread as the ~JavaThread
2428 // destructor has completed.
2429
2430 if (thread->SR_lock() == NULL) {
2431 return;
2432 }
2433
2434 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
2435
2436 OSThread* osthread = thread->osthread();
2437
2438 os::SuspendResume::State current = osthread->sr.state();
2439 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
2440 suspend_save_context(osthread, siginfo, context);
2441
2442 // attempt to switch the state, we assume we had a SUSPEND_REQUEST
2443 os::SuspendResume::State state = osthread->sr.suspended();
2444 if (state == os::SuspendResume::SR_SUSPENDED) {
2445 sigset_t suspend_set; // signals for sigsuspend()
2446
2447 // get current set of blocked signals and unblock resume signal
2448 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2449 sigdelset(&suspend_set, SR_signum);
2450
2451 sr_semaphore.signal();
2452 // wait here until we are resumed
2453 while (1) {
2454 sigsuspend(&suspend_set);
2455
2456 os::SuspendResume::State result = osthread->sr.running();
2457 if (result == os::SuspendResume::SR_RUNNING) {
2458 sr_semaphore.signal();
2459 break;
2460 } else if (result != os::SuspendResume::SR_SUSPENDED) {
2461 ShouldNotReachHere();
2462 }
2463 }
2464
2465 } else if (state == os::SuspendResume::SR_RUNNING) {
2466 // request was cancelled, continue
2467 } else {
2468 ShouldNotReachHere();
2469 }
2470
2471 resume_clear_context(osthread);
2472 } else if (current == os::SuspendResume::SR_RUNNING) {
2473 // request was cancelled, continue
2474 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
2475 // ignore
2476 } else {
2477 // ignore
2478 }
2479
2480 errno = old_errno;
2481 }
2482
2483
2484 static int SR_initialize() {
2485 struct sigaction act;
2486 char *s;
2487 // Get signal number to use for suspend/resume
2488 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2489 int sig = ::strtol(s, 0, 10);
2490 if (sig > MAX2(SIGSEGV, SIGBUS) && // See 4355769.
2491 sig < NSIG) { // Must be legal signal and fit into sigflags[].
2492 SR_signum = sig;
2493 } else {
2494 warning("You set _JAVA_SR_SIGNUM=%d. It must be in range [%d, %d]. Using %d instead.",
2495 sig, MAX2(SIGSEGV, SIGBUS)+1, NSIG-1, SR_signum);
2496 }
2497 }
2498
2499 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2500 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2501
2502 sigemptyset(&SR_sigset);
2503 sigaddset(&SR_sigset, SR_signum);
2504
2505 // Set up signal handler for suspend/resume
2506 act.sa_flags = SA_RESTART|SA_SIGINFO;
2507 act.sa_handler = (void (*)(int)) SR_handler;
2508
2509 // SR_signum is blocked by default.
2510 // 4528190 - We also need to block pthread restart signal (32 on all
2511 // supported Bsd platforms). Note that BsdThreads need to block
2512 // this signal for all threads to work properly. So we don't have
2513 // to use hard-coded signal number when setting up the mask.
2514 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2515
2516 if (sigaction(SR_signum, &act, 0) == -1) {
2517 return -1;
2518 }
2519
2520 // Save signal flag
2521 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2522 return 0;
2523 }
2524
2525 static int sr_notify(OSThread* osthread) {
2526 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2527 assert_status(status == 0, status, "pthread_kill");
2528 return status;
2529 }
2530
2531 // "Randomly" selected value for how long we want to spin
2532 // before bailing out on suspending a thread, also how often
2533 // we send a signal to a thread we want to resume
2534 static const int RANDOMLY_LARGE_INTEGER = 1000000;
2535 static const int RANDOMLY_LARGE_INTEGER2 = 100;
2536
2537 // returns true on success and false on error - really an error is fatal
2538 // but this seems the normal response to library errors
2539 static bool do_suspend(OSThread* osthread) {
2540 assert(osthread->sr.is_running(), "thread should be running");
2541 assert(!sr_semaphore.trywait(), "semaphore has invalid state");
2542
2543 // mark as suspended and send signal
2544 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
2545 // failed to switch, state wasn't running?
2546 ShouldNotReachHere();
2547 return false;
2548 }
2549
2550 if (sr_notify(osthread) != 0) {
2551 ShouldNotReachHere();
2552 }
2553
2554 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
2555 while (true) {
2556 if (sr_semaphore.timedwait(2)) {
2557 break;
2558 } else {
2559 // timeout
2560 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
2561 if (cancelled == os::SuspendResume::SR_RUNNING) {
2562 return false;
2563 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
2564 // make sure that we consume the signal on the semaphore as well
2565 sr_semaphore.wait();
2566 break;
2567 } else {
2568 ShouldNotReachHere();
2569 return false;
2570 }
2571 }
2572 }
2573
2574 guarantee(osthread->sr.is_suspended(), "Must be suspended");
2575 return true;
2576 }
2577
2578 static void do_resume(OSThread* osthread) {
2579 assert(osthread->sr.is_suspended(), "thread should be suspended");
2580 assert(!sr_semaphore.trywait(), "invalid semaphore state");
2581
2582 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
2583 // failed to switch to WAKEUP_REQUEST
2584 ShouldNotReachHere();
2585 return;
2586 }
2587
2588 while (true) {
2589 if (sr_notify(osthread) == 0) {
2590 if (sr_semaphore.timedwait(2)) {
2591 if (osthread->sr.is_running()) {
2592 return;
2593 }
2594 }
2595 } else {
2596 ShouldNotReachHere();
2597 }
2598 }
2599
2600 guarantee(osthread->sr.is_running(), "Must be running!");
2601 }
2602
2603 ///////////////////////////////////////////////////////////////////////////////////
2604 // signal handling (except suspend/resume)
2605
2606 // This routine may be used by user applications as a "hook" to catch signals.
2607 // The user-defined signal handler must pass unrecognized signals to this
2608 // routine, and if it returns true (non-zero), then the signal handler must
2609 // return immediately. If the flag "abort_if_unrecognized" is true, then this
2610 // routine will never retun false (zero), but instead will execute a VM panic
2611 // routine kill the process.
2612 //
2613 // If this routine returns false, it is OK to call it again. This allows
2614 // the user-defined signal handler to perform checks either before or after
2615 // the VM performs its own checks. Naturally, the user code would be making
2616 // a serious error if it tried to handle an exception (such as a null check
2617 // or breakpoint) that the VM was generating for its own correct operation.
2618 //
2619 // This routine may recognize any of the following kinds of signals:
2620 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
2621 // It should be consulted by handlers for any of those signals.
2622 //
2623 // The caller of this routine must pass in the three arguments supplied
2624 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
2625 // field of the structure passed to sigaction(). This routine assumes that
2626 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
2627 //
2628 // Note that the VM will print warnings if it detects conflicting signal
2629 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
2630 //
2631 extern "C" JNIEXPORT int JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
2632 void* ucontext,
2633 int abort_if_unrecognized);
2634
2635 static void signalHandler(int sig, siginfo_t* info, void* uc) {
2636 assert(info != NULL && uc != NULL, "it must be old kernel");
2637 int orig_errno = errno; // Preserve errno value over signal handler.
2638 JVM_handle_bsd_signal(sig, info, uc, true);
2639 errno = orig_errno;
2640 }
2641
2642
2643 // This boolean allows users to forward their own non-matching signals
2644 // to JVM_handle_bsd_signal, harmlessly.
2645 bool os::Bsd::signal_handlers_are_installed = false;
2646
2647 // For signal-chaining
2648 bool os::Bsd::libjsig_is_loaded = false;
2649 typedef struct sigaction *(*get_signal_t)(int);
2650 get_signal_t os::Bsd::get_signal_action = NULL;
2651
2652 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
2653 struct sigaction *actp = NULL;
2654
2655 if (libjsig_is_loaded) {
2656 // Retrieve the old signal handler from libjsig
2657 actp = (*get_signal_action)(sig);
2658 }
2659 if (actp == NULL) {
2660 // Retrieve the preinstalled signal handler from jvm
2661 actp = os::Posix::get_preinstalled_handler(sig);
2662 }
2663
2664 return actp;
2665 }
2666
2667 static bool call_chained_handler(struct sigaction *actp, int sig,
2668 siginfo_t *siginfo, void *context) {
2669 // Call the old signal handler
2670 if (actp->sa_handler == SIG_DFL) {
2671 // It's more reasonable to let jvm treat it as an unexpected exception
2672 // instead of taking the default action.
2673 return false;
2674 } else if (actp->sa_handler != SIG_IGN) {
2675 if ((actp->sa_flags & SA_NODEFER) == 0) {
2676 // automaticlly block the signal
2677 sigaddset(&(actp->sa_mask), sig);
2678 }
2679
2680 sa_handler_t hand;
2681 sa_sigaction_t sa;
2682 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
2683 // retrieve the chained handler
2684 if (siginfo_flag_set) {
2685 sa = actp->sa_sigaction;
2686 } else {
2687 hand = actp->sa_handler;
2688 }
2689
2690 if ((actp->sa_flags & SA_RESETHAND) != 0) {
2691 actp->sa_handler = SIG_DFL;
2692 }
2693
2694 // try to honor the signal mask
2695 sigset_t oset;
2696 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
2697
2698 // call into the chained handler
2699 if (siginfo_flag_set) {
2700 (*sa)(sig, siginfo, context);
2701 } else {
2702 (*hand)(sig);
2703 }
2704
2705 // restore the signal mask
2706 pthread_sigmask(SIG_SETMASK, &oset, 0);
2707 }
2708 // Tell jvm's signal handler the signal is taken care of.
2709 return true;
2710 }
2711
2712 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
2713 bool chained = false;
2714 // signal-chaining
2715 if (UseSignalChaining) {
2716 struct sigaction *actp = get_chained_signal_action(sig);
2717 if (actp != NULL) {
2718 chained = call_chained_handler(actp, sig, siginfo, context);
2719 }
2720 }
2721 return chained;
2722 }
2723
2724 // for diagnostic
2725 int sigflags[NSIG];
2726
2727 int os::Bsd::get_our_sigflags(int sig) {
2728 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
2729 return sigflags[sig];
2730 }
2731
2732 void os::Bsd::set_our_sigflags(int sig, int flags) {
2733 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
2734 if (sig > 0 && sig < NSIG) {
2735 sigflags[sig] = flags;
2736 }
2737 }
2738
2739 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
2740 // Check for overwrite.
2741 struct sigaction oldAct;
2742 sigaction(sig, (struct sigaction*)NULL, &oldAct);
2743
2744 void* oldhand = oldAct.sa_sigaction
2745 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
2746 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
2747 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
2748 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
2749 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
2750 if (AllowUserSignalHandlers || !set_installed) {
2751 // Do not overwrite; user takes responsibility to forward to us.
2752 return;
2753 } else if (UseSignalChaining) {
2754 // save the old handler in jvm
2755 os::Posix::save_preinstalled_handler(sig, oldAct);
2756 // libjsig also interposes the sigaction() call below and saves the
2757 // old sigaction on it own.
2758 } else {
2759 fatal("Encountered unexpected pre-existing sigaction handler "
2760 "%#lx for signal %d.", (long)oldhand, sig);
2761 }
2762 }
2763
2764 struct sigaction sigAct;
2765 sigfillset(&(sigAct.sa_mask));
2766 sigAct.sa_handler = SIG_DFL;
2767 if (!set_installed) {
2768 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
2769 } else {
2770 sigAct.sa_sigaction = signalHandler;
2771 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
2772 }
2773 #ifdef __APPLE__
2774 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV
2775 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages"
2776 // if the signal handler declares it will handle it on alternate stack.
2777 // Notice we only declare we will handle it on alt stack, but we are not
2778 // actually going to use real alt stack - this is just a workaround.
2779 // Please see ux_exception.c, method catch_mach_exception_raise for details
2780 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c
2781 if (sig == SIGSEGV) {
2782 sigAct.sa_flags |= SA_ONSTACK;
2783 }
2784 #endif
2785
2786 // Save flags, which are set by ours
2787 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
2788 sigflags[sig] = sigAct.sa_flags;
2789
2790 int ret = sigaction(sig, &sigAct, &oldAct);
2791 assert(ret == 0, "check");
2792
2793 void* oldhand2 = oldAct.sa_sigaction
2794 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
2795 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
2796 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
2797 }
2798
2799 // install signal handlers for signals that HotSpot needs to
2800 // handle in order to support Java-level exception handling.
2801
2802 void os::Bsd::install_signal_handlers() {
2803 if (!signal_handlers_are_installed) {
2804 signal_handlers_are_installed = true;
2805
2806 // signal-chaining
2807 typedef void (*signal_setting_t)();
2808 signal_setting_t begin_signal_setting = NULL;
2809 signal_setting_t end_signal_setting = NULL;
2810 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
2811 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
2812 if (begin_signal_setting != NULL) {
2813 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
2814 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
2815 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
2816 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
2817 libjsig_is_loaded = true;
2818 assert(UseSignalChaining, "should enable signal-chaining");
2819 }
2820 if (libjsig_is_loaded) {
2821 // Tell libjsig jvm is setting signal handlers
2822 (*begin_signal_setting)();
2823 }
2824
2825 set_signal_handler(SIGSEGV, true);
2826 set_signal_handler(SIGPIPE, true);
2827 set_signal_handler(SIGBUS, true);
2828 set_signal_handler(SIGILL, true);
2829 set_signal_handler(SIGFPE, true);
2830 set_signal_handler(SIGXFSZ, true);
2831
2832 #if defined(__APPLE__)
2833 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
2834 // signals caught and handled by the JVM. To work around this, we reset the mach task
2835 // signal handler that's placed on our process by CrashReporter. This disables
2836 // CrashReporter-based reporting.
2837 //
2838 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
2839 // on caught fatal signals.
2840 //
2841 // Additionally, gdb installs both standard BSD signal handlers, and mach exception
2842 // handlers. By replacing the existing task exception handler, we disable gdb's mach
2843 // exception handling, while leaving the standard BSD signal handlers functional.
2844 kern_return_t kr;
2845 kr = task_set_exception_ports(mach_task_self(),
2846 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
2847 MACH_PORT_NULL,
2848 EXCEPTION_STATE_IDENTITY,
2849 MACHINE_THREAD_STATE);
2850
2851 assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
2852 #endif
2853
2854 if (libjsig_is_loaded) {
2855 // Tell libjsig jvm finishes setting signal handlers
2856 (*end_signal_setting)();
2857 }
2858
2859 // We don't activate signal checker if libjsig is in place, we trust ourselves
2860 // and if UserSignalHandler is installed all bets are off
2861 if (CheckJNICalls) {
2862 if (libjsig_is_loaded) {
2863 log_debug(jni, resolve)("Info: libjsig is activated, all active signal checking is disabled");
2864 check_signals = false;
2865 }
2866 if (AllowUserSignalHandlers) {
2867 log_debug(jni, resolve)("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
2868 check_signals = false;
2869 }
2870 }
2871 }
2872 }
2873
2874
2875 /////
2876 // glibc on Bsd platform uses non-documented flag
2877 // to indicate, that some special sort of signal
2878 // trampoline is used.
2879 // We will never set this flag, and we should
2880 // ignore this flag in our diagnostic
2881 #ifdef SIGNIFICANT_SIGNAL_MASK
2882 #undef SIGNIFICANT_SIGNAL_MASK
2883 #endif
2884 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
2885
2886 static const char* get_signal_handler_name(address handler,
2887 char* buf, int buflen) {
2888 int offset;
2889 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
2890 if (found) {
2891 // skip directory names
2892 const char *p1, *p2;
2893 p1 = buf;
2894 size_t len = strlen(os::file_separator());
2895 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
2896 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
2897 } else {
2898 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
2899 }
2900 return buf;
2901 }
2902
2903 static void print_signal_handler(outputStream* st, int sig,
2904 char* buf, size_t buflen) {
2905 struct sigaction sa;
2906
2907 sigaction(sig, NULL, &sa);
2908
2909 // See comment for SIGNIFICANT_SIGNAL_MASK define
2910 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
2911
2912 st->print("%s: ", os::exception_name(sig, buf, buflen));
2913
2914 address handler = (sa.sa_flags & SA_SIGINFO)
2915 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
2916 : CAST_FROM_FN_PTR(address, sa.sa_handler);
2917
2918 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
2919 st->print("SIG_DFL");
2920 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
2921 st->print("SIG_IGN");
2922 } else {
2923 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
2924 }
2925
2926 st->print(", sa_mask[0]=");
2927 os::Posix::print_signal_set_short(st, &sa.sa_mask);
2928
2929 address rh = VMError::get_resetted_sighandler(sig);
2930 // May be, handler was resetted by VMError?
2931 if (rh != NULL) {
2932 handler = rh;
2933 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
2934 }
2935
2936 st->print(", sa_flags=");
2937 os::Posix::print_sa_flags(st, sa.sa_flags);
2938
2939 // Check: is it our handler?
2940 if (handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
2941 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
2942 // It is our signal handler
2943 // check for flags, reset system-used one!
2944 if ((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
2945 st->print(
2946 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
2947 os::Bsd::get_our_sigflags(sig));
2948 }
2949 }
2950 st->cr();
2951 }
2952
2953
2954 #define DO_SIGNAL_CHECK(sig) \
2955 do { \
2956 if (!sigismember(&check_signal_done, sig)) { \
2957 os::Bsd::check_signal_handler(sig); \
2958 } \
2959 } while (0)
2960
2961 // This method is a periodic task to check for misbehaving JNI applications
2962 // under CheckJNI, we can add any periodic checks here
2963
2964 void os::run_periodic_checks() {
2965
2966 if (check_signals == false) return;
2967
2968 // SEGV and BUS if overridden could potentially prevent
2969 // generation of hs*.log in the event of a crash, debugging
2970 // such a case can be very challenging, so we absolutely
2971 // check the following for a good measure:
2972 DO_SIGNAL_CHECK(SIGSEGV);
2973 DO_SIGNAL_CHECK(SIGILL);
2974 DO_SIGNAL_CHECK(SIGFPE);
2975 DO_SIGNAL_CHECK(SIGBUS);
2976 DO_SIGNAL_CHECK(SIGPIPE);
2977 DO_SIGNAL_CHECK(SIGXFSZ);
2978
2979
2980 // ReduceSignalUsage allows the user to override these handlers
2981 // see comments at the very top and jvm_md.h
2982 if (!ReduceSignalUsage) {
2983 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
2984 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
2985 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
2986 DO_SIGNAL_CHECK(BREAK_SIGNAL);
2987 }
2988
2989 DO_SIGNAL_CHECK(SR_signum);
2990 }
2991
2992 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
2993
2994 static os_sigaction_t os_sigaction = NULL;
2995
2996 void os::Bsd::check_signal_handler(int sig) {
2997 char buf[O_BUFLEN];
2998 address jvmHandler = NULL;
2999
3000
3001 struct sigaction act;
3002 if (os_sigaction == NULL) {
3003 // only trust the default sigaction, in case it has been interposed
3004 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
3005 if (os_sigaction == NULL) return;
3006 }
3007
3008 os_sigaction(sig, (struct sigaction*)NULL, &act);
3009
3010
3011 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3012
3013 address thisHandler = (act.sa_flags & SA_SIGINFO)
3014 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3015 : CAST_FROM_FN_PTR(address, act.sa_handler);
3016
3017
3018 switch (sig) {
3019 case SIGSEGV:
3020 case SIGBUS:
3021 case SIGFPE:
3022 case SIGPIPE:
3023 case SIGILL:
3024 case SIGXFSZ:
3025 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
3026 break;
3027
3028 case SHUTDOWN1_SIGNAL:
3029 case SHUTDOWN2_SIGNAL:
3030 case SHUTDOWN3_SIGNAL:
3031 case BREAK_SIGNAL:
3032 jvmHandler = (address)user_handler();
3033 break;
3034
3035 default:
3036 if (sig == SR_signum) {
3037 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3038 } else {
3039 return;
3040 }
3041 break;
3042 }
3043
3044 if (thisHandler != jvmHandler) {
3045 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3046 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3047 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3048 // No need to check this sig any longer
3049 sigaddset(&check_signal_done, sig);
3050 // Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN
3051 if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) {
3052 tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell",
3053 exception_name(sig, buf, O_BUFLEN));
3054 }
3055 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3056 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3057 tty->print("expected:");
3058 os::Posix::print_sa_flags(tty, os::Bsd::get_our_sigflags(sig));
3059 tty->cr();
3060 tty->print(" found:");
3061 os::Posix::print_sa_flags(tty, act.sa_flags);
3062 tty->cr();
3063 // No need to check this sig any longer
3064 sigaddset(&check_signal_done, sig);
3065 }
3066
3067 // Dump all the signal
3068 if (sigismember(&check_signal_done, sig)) {
3069 print_signal_handlers(tty, buf, O_BUFLEN);
3070 }
3071 }
3072
3073 extern void report_error(char* file_name, int line_no, char* title,
3074 char* format, ...);
3075
3076 // this is called _before_ the most of global arguments have been parsed
3077 void os::init(void) {
3078 char dummy; // used to get a guess on initial stack address
3079
3080 clock_tics_per_sec = CLK_TCK;
3081
3082 init_random(1234567);
3083
3084 Bsd::set_page_size(getpagesize());
3085 if (Bsd::page_size() == -1) {
3086 fatal("os_bsd.cpp: os::init: sysconf failed (%s)", os::strerror(errno));
3087 }
3088 init_page_sizes((size_t) Bsd::page_size());
3089
3090 Bsd::initialize_system_info();
3091
3092 // _main_thread points to the thread that created/loaded the JVM.
3093 Bsd::_main_thread = pthread_self();
3094
3095 Bsd::clock_init();
3096 initial_time_count = javaTimeNanos();
3097
3098 os::Posix::init();
3099 }
3100
3101 // To install functions for atexit system call
3102 extern "C" {
3103 static void perfMemory_exit_helper() {
3104 perfMemory_exit();
3105 }
3106 }
3107
3108 // this is called _after_ the global arguments have been parsed
3109 jint os::init_2(void) {
3110
3111 // This could be set after os::Posix::init() but all platforms
3112 // have to set it the same so we have to mirror Solaris.
3113 DEBUG_ONLY(os::set_mutex_init_done();)
3114
3115 os::Posix::init_2();
3116
3117 // initialize suspend/resume support - must do this before signal_sets_init()
3118 if (SR_initialize() != 0) {
3119 perror("SR_initialize failed");
3120 return JNI_ERR;
3121 }
3122
3123 Bsd::signal_sets_init();
3124 Bsd::install_signal_handlers();
3125 // Initialize data for jdk.internal.misc.Signal
3126 if (!ReduceSignalUsage) {
3127 jdk_misc_signal_init();
3128 }
3129
3130 // Check and sets minimum stack sizes against command line options
3131 if (Posix::set_minimum_stack_sizes() == JNI_ERR) {
3132 return JNI_ERR;
3133 }
3134
3135 // Not supported.
3136 FLAG_SET_ERGO(UseNUMA, false);
3137 FLAG_SET_ERGO(UseNUMAInterleaving, false);
3138
3139 if (MaxFDLimit) {
3140 // set the number of file descriptors to max. print out error
3141 // if getrlimit/setrlimit fails but continue regardless.
3142 struct rlimit nbr_files;
3143 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3144 if (status != 0) {
3145 log_info(os)("os::init_2 getrlimit failed: %s", os::strerror(errno));
3146 } else {
3147 nbr_files.rlim_cur = nbr_files.rlim_max;
3148
3149 #ifdef __APPLE__
3150 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3151 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3152 // be used instead
3153 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3154 #endif
3155
3156 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3157 if (status != 0) {
3158 log_info(os)("os::init_2 setrlimit failed: %s", os::strerror(errno));
3159 }
3160 }
3161 }
3162
3163 // at-exit methods are called in the reverse order of their registration.
3164 // atexit functions are called on return from main or as a result of a
3165 // call to exit(3C). There can be only 32 of these functions registered
3166 // and atexit() does not set errno.
3167
3168 if (PerfAllowAtExitRegistration) {
3169 // only register atexit functions if PerfAllowAtExitRegistration is set.
3170 // atexit functions can be delayed until process exit time, which
3171 // can be problematic for embedded VM situations. Embedded VMs should
3172 // call DestroyJavaVM() to assure that VM resources are released.
3173
3174 // note: perfMemory_exit_helper atexit function may be removed in
3175 // the future if the appropriate cleanup code can be added to the
3176 // VM_Exit VMOperation's doit method.
3177 if (atexit(perfMemory_exit_helper) != 0) {
3178 warning("os::init_2 atexit(perfMemory_exit_helper) failed");
3179 }
3180 }
3181
3182 // initialize thread priority policy
3183 prio_init();
3184
3185 #ifdef __APPLE__
3186 // dynamically link to objective c gc registration
3187 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3188 if (handleLibObjc != NULL) {
3189 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3190 }
3191 #endif
3192
3193 return JNI_OK;
3194 }
3195
3196 int os::active_processor_count() {
3197 // User has overridden the number of active processors
3198 if (ActiveProcessorCount > 0) {
3199 log_trace(os)("active_processor_count: "
3200 "active processor count set by user : %d",
3201 ActiveProcessorCount);
3202 return ActiveProcessorCount;
3203 }
3204
3205 return _processor_count;
3206 }
3207
3208 #ifdef __APPLE__
3209 uint os::processor_id() {
3210 // Get the initial APIC id and return the associated processor id. The initial APIC
3211 // id is limited to 8-bits, which means we can have at most 256 unique APIC ids. If
3212 // the system has more processors (or the initial APIC ids are discontiguous) the
3213 // APIC id will be truncated and more than one processor will potentially share the
3214 // same processor id. This is not optimal, but unlikely to happen in practice. Should
3215 // this become a real problem we could switch to using x2APIC ids, which are 32-bit
3216 // wide. However, note that x2APIC is Intel-specific, and the wider number space
3217 // would require a more complicated mapping approach.
3218 uint eax = 0x1;
3219 uint ebx;
3220 uint ecx = 0;
3221 uint edx;
3222
3223 __asm__ ("cpuid\n\t" : "+a" (eax), "+b" (ebx), "+c" (ecx), "+d" (edx) : );
3224
3225 uint apic_id = (ebx >> 24) & (processor_id_map_size - 1);
3226 int processor_id = Atomic::load(&processor_id_map[apic_id]);
3227
3228 while (processor_id < 0) {
3229 // Assign processor id to APIC id
3230 processor_id = Atomic::cmpxchg(&processor_id_map[apic_id], processor_id_unassigned, processor_id_assigning);
3231 if (processor_id == processor_id_unassigned) {
3232 processor_id = Atomic::fetch_and_add(&processor_id_next, 1) % os::processor_count();
3233 Atomic::store(&processor_id_map[apic_id], processor_id);
3234 }
3235 }
3236
3237 assert(processor_id >= 0 && processor_id < os::processor_count(), "invalid processor id");
3238
3239 return (uint)processor_id;
3240 }
3241 #endif
3242
3243 void os::set_native_thread_name(const char *name) {
3244 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3245 // This is only supported in Snow Leopard and beyond
3246 if (name != NULL) {
3247 // Add a "Java: " prefix to the name
3248 char buf[MAXTHREADNAMESIZE];
3249 snprintf(buf, sizeof(buf), "Java: %s", name);
3250 pthread_setname_np(buf);
3251 }
3252 #endif
3253 }
3254
3255 bool os::bind_to_processor(uint processor_id) {
3256 // Not yet implemented.
3257 return false;
3258 }
3259
3260 void os::SuspendedThreadTask::internal_do_task() {
3261 if (do_suspend(_thread->osthread())) {
3262 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
3263 do_task(context);
3264 do_resume(_thread->osthread());
3265 }
3266 }
3267
3268 ////////////////////////////////////////////////////////////////////////////////
3269 // debug support
3270
3271 bool os::find(address addr, outputStream* st) {
3272 Dl_info dlinfo;
3273 memset(&dlinfo, 0, sizeof(dlinfo));
3274 if (dladdr(addr, &dlinfo) != 0) {
3275 st->print(INTPTR_FORMAT ": ", (intptr_t)addr);
3276 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) {
3277 st->print("%s+%#x", dlinfo.dli_sname,
3278 (uint)((uintptr_t)addr - (uintptr_t)dlinfo.dli_saddr));
3279 } else if (dlinfo.dli_fbase != NULL) {
3280 st->print("<offset %#x>", (uint)((uintptr_t)addr - (uintptr_t)dlinfo.dli_fbase));
3281 } else {
3282 st->print("<absolute address>");
3283 }
3284 if (dlinfo.dli_fname != NULL) {
3285 st->print(" in %s", dlinfo.dli_fname);
3286 }
3287 if (dlinfo.dli_fbase != NULL) {
3288 st->print(" at " INTPTR_FORMAT, (intptr_t)dlinfo.dli_fbase);
3289 }
3290 st->cr();
3291
3292 if (Verbose) {
3293 // decode some bytes around the PC
3294 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
3295 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size());
3296 address lowest = (address) dlinfo.dli_sname;
3297 if (!lowest) lowest = (address) dlinfo.dli_fbase;
3298 if (begin < lowest) begin = lowest;
3299 Dl_info dlinfo2;
3300 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr
3301 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) {
3302 end = (address) dlinfo2.dli_saddr;
3303 }
3304 Disassembler::decode(begin, end, st);
3305 }
3306 return true;
3307 }
3308 return false;
3309 }
3310
3311 ////////////////////////////////////////////////////////////////////////////////
3312 // misc
3313
3314 // This does not do anything on Bsd. This is basically a hook for being
3315 // able to use structured exception handling (thread-local exception filters)
3316 // on, e.g., Win32.
3317 void os::os_exception_wrapper(java_call_t f, JavaValue* value,
3318 const methodHandle& method, JavaCallArguments* args,
3319 Thread* thread) {
3320 f(value, method, args, thread);
3321 }
3322
3323 void os::print_statistics() {
3324 }
3325
3326 bool os::message_box(const char* title, const char* message) {
3327 int i;
3328 fdStream err(defaultStream::error_fd());
3329 for (i = 0; i < 78; i++) err.print_raw("=");
3330 err.cr();
3331 err.print_raw_cr(title);
3332 for (i = 0; i < 78; i++) err.print_raw("-");
3333 err.cr();
3334 err.print_raw_cr(message);
3335 for (i = 0; i < 78; i++) err.print_raw("=");
3336 err.cr();
3337
3338 char buf[16];
3339 // Prevent process from exiting upon "read error" without consuming all CPU
3340 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3341
3342 return buf[0] == 'y' || buf[0] == 'Y';
3343 }
3344
3345 static inline struct timespec get_mtime(const char* filename) {
3346 struct stat st;
3347 int ret = os::stat(filename, &st);
3348 assert(ret == 0, "failed to stat() file '%s': %s", filename, os::strerror(errno));
3349 #ifdef __APPLE__
3350 return st.st_mtimespec;
3351 #else
3352 return st.st_mtim;
3353 #endif
3354 }
3355
3356 int os::compare_file_modified_times(const char* file1, const char* file2) {
3357 struct timespec filetime1 = get_mtime(file1);
3358 struct timespec filetime2 = get_mtime(file2);
3359 int diff = filetime1.tv_sec - filetime2.tv_sec;
3360 if (diff == 0) {
3361 return filetime1.tv_nsec - filetime2.tv_nsec;
3362 }
3363 return diff;
3364 }
3365
3366 // Is a (classpath) directory empty?
3367 bool os::dir_is_empty(const char* path) {
3368 DIR *dir = NULL;
3369 struct dirent *ptr;
3370
3371 dir = opendir(path);
3372 if (dir == NULL) return true;
3373
3374 // Scan the directory
3375 bool result = true;
3376 while (result && (ptr = readdir(dir)) != NULL) {
3377 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3378 result = false;
3379 }
3380 }
3381 closedir(dir);
3382 return result;
3383 }
3384
3385 // This code originates from JDK's sysOpen and open64_w
3386 // from src/solaris/hpi/src/system_md.c
3387
3388 int os::open(const char *path, int oflag, int mode) {
3389 if (strlen(path) > MAX_PATH - 1) {
3390 errno = ENAMETOOLONG;
3391 return -1;
3392 }
3393 int fd;
3394
3395 fd = ::open(path, oflag, mode);
3396 if (fd == -1) return -1;
3397
3398 // If the open succeeded, the file might still be a directory
3399 {
3400 struct stat buf;
3401 int ret = ::fstat(fd, &buf);
3402 int st_mode = buf.st_mode;
3403
3404 if (ret != -1) {
3405 if ((st_mode & S_IFMT) == S_IFDIR) {
3406 errno = EISDIR;
3407 ::close(fd);
3408 return -1;
3409 }
3410 } else {
3411 ::close(fd);
3412 return -1;
3413 }
3414 }
3415
3416 // All file descriptors that are opened in the JVM and not
3417 // specifically destined for a subprocess should have the
3418 // close-on-exec flag set. If we don't set it, then careless 3rd
3419 // party native code might fork and exec without closing all
3420 // appropriate file descriptors (e.g. as we do in closeDescriptors in
3421 // UNIXProcess.c), and this in turn might:
3422 //
3423 // - cause end-of-file to fail to be detected on some file
3424 // descriptors, resulting in mysterious hangs, or
3425 //
3426 // - might cause an fopen in the subprocess to fail on a system
3427 // suffering from bug 1085341.
3428 //
3429 // (Yes, the default setting of the close-on-exec flag is a Unix
3430 // design flaw)
3431 //
3432 // See:
3433 // 1085341: 32-bit stdio routines should support file descriptors >255
3434 // 4843136: (process) pipe file descriptor from Runtime.exec not being closed
3435 // 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
3436 //
3437 #ifdef FD_CLOEXEC
3438 {
3439 int flags = ::fcntl(fd, F_GETFD);
3440 if (flags != -1) {
3441 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
3442 }
3443 }
3444 #endif
3445
3446 return fd;
3447 }
3448
3449
3450 // create binary file, rewriting existing file if required
3451 int os::create_binary_file(const char* path, bool rewrite_existing) {
3452 int oflags = O_WRONLY | O_CREAT;
3453 if (!rewrite_existing) {
3454 oflags |= O_EXCL;
3455 }
3456 return ::open(path, oflags, S_IREAD | S_IWRITE);
3457 }
3458
3459 // return current position of file pointer
3460 jlong os::current_file_offset(int fd) {
3461 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
3462 }
3463
3464 // move file pointer to the specified offset
3465 jlong os::seek_to_file_offset(int fd, jlong offset) {
3466 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
3467 }
3468
3469 // This code originates from JDK's sysAvailable
3470 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
3471
3472 int os::available(int fd, jlong *bytes) {
3473 jlong cur, end;
3474 int mode;
3475 struct stat buf;
3476
3477 if (::fstat(fd, &buf) >= 0) {
3478 mode = buf.st_mode;
3479 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
3480 int n;
3481 if (::ioctl(fd, FIONREAD, &n) >= 0) {
3482 *bytes = n;
3483 return 1;
3484 }
3485 }
3486 }
3487 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
3488 return 0;
3489 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
3490 return 0;
3491 } else if (::lseek(fd, cur, SEEK_SET) == -1) {
3492 return 0;
3493 }
3494 *bytes = end - cur;
3495 return 1;
3496 }
3497
3498 // Map a block of memory.
3499 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
3500 char *addr, size_t bytes, bool read_only,
3501 bool allow_exec) {
3502 int prot;
3503 int flags;
3504
3505 if (read_only) {
3506 prot = PROT_READ;
3507 flags = MAP_SHARED;
3508 } else {
3509 prot = PROT_READ | PROT_WRITE;
3510 flags = MAP_PRIVATE;
3511 }
3512
3513 if (allow_exec) {
3514 prot |= PROT_EXEC;
3515 }
3516
3517 if (addr != NULL) {
3518 flags |= MAP_FIXED;
3519 }
3520
3521 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
3522 fd, file_offset);
3523 if (mapped_address == MAP_FAILED) {
3524 return NULL;
3525 }
3526 return mapped_address;
3527 }
3528
3529
3530 // Remap a block of memory.
3531 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
3532 char *addr, size_t bytes, bool read_only,
3533 bool allow_exec) {
3534 // same as map_memory() on this OS
3535 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
3536 allow_exec);
3537 }
3538
3539
3540 // Unmap a block of memory.
3541 bool os::pd_unmap_memory(char* addr, size_t bytes) {
3542 return munmap(addr, bytes) == 0;
3543 }
3544
3545 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
3546 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
3547 // of a thread.
3548 //
3549 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
3550 // the fast estimate available on the platform.
3551
3552 jlong os::current_thread_cpu_time() {
3553 #ifdef __APPLE__
3554 return os::thread_cpu_time(Thread::current(), true /* user + sys */);
3555 #else
3556 Unimplemented();
3557 return 0;
3558 #endif
3559 }
3560
3561 jlong os::thread_cpu_time(Thread* thread) {
3562 #ifdef __APPLE__
3563 return os::thread_cpu_time(thread, true /* user + sys */);
3564 #else
3565 Unimplemented();
3566 return 0;
3567 #endif
3568 }
3569
3570 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
3571 #ifdef __APPLE__
3572 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
3573 #else
3574 Unimplemented();
3575 return 0;
3576 #endif
3577 }
3578
3579 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
3580 #ifdef __APPLE__
3581 struct thread_basic_info tinfo;
3582 mach_msg_type_number_t tcount = THREAD_INFO_MAX;
3583 kern_return_t kr;
3584 thread_t mach_thread;
3585
3586 mach_thread = thread->osthread()->thread_id();
3587 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
3588 if (kr != KERN_SUCCESS) {
3589 return -1;
3590 }
3591
3592 if (user_sys_cpu_time) {
3593 jlong nanos;
3594 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
3595 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
3596 return nanos;
3597 } else {
3598 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
3599 }
3600 #else
3601 Unimplemented();
3602 return 0;
3603 #endif
3604 }
3605
3606
3607 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
3608 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
3609 info_ptr->may_skip_backward = false; // elapsed time not wall time
3610 info_ptr->may_skip_forward = false; // elapsed time not wall time
3611 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
3612 }
3613
3614 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
3615 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
3616 info_ptr->may_skip_backward = false; // elapsed time not wall time
3617 info_ptr->may_skip_forward = false; // elapsed time not wall time
3618 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
3619 }
3620
3621 bool os::is_thread_cpu_time_supported() {
3622 #ifdef __APPLE__
3623 return true;
3624 #else
3625 return false;
3626 #endif
3627 }
3628
3629 // System loadavg support. Returns -1 if load average cannot be obtained.
3630 // Bsd doesn't yet have a (official) notion of processor sets,
3631 // so just return the system wide load average.
3632 int os::loadavg(double loadavg[], int nelem) {
3633 return ::getloadavg(loadavg, nelem);
3634 }
3635
3636 void os::pause() {
3637 char filename[MAX_PATH];
3638 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
3639 jio_snprintf(filename, MAX_PATH, "%s", PauseAtStartupFile);
3640 } else {
3641 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
3642 }
3643
3644 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
3645 if (fd != -1) {
3646 struct stat buf;
3647 ::close(fd);
3648 while (::stat(filename, &buf) == 0) {
3649 (void)::poll(NULL, 0, 100);
3650 }
3651 } else {
3652 jio_fprintf(stderr,
3653 "Could not open pause file '%s', continuing immediately.\n", filename);
3654 }
3655 }
3656
3657 // Darwin has no "environ" in a dynamic library.
3658 #ifdef __APPLE__
3659 #include <crt_externs.h>
3660 #define environ (*_NSGetEnviron())
3661 #else
3662 extern char** environ;
3663 #endif
3664
3665 // Run the specified command in a separate process. Return its exit value,
3666 // or -1 on failure (e.g. can't fork a new process).
3667 // Unlike system(), this function can be called from signal handler. It
3668 // doesn't block SIGINT et al.
3669 int os::fork_and_exec(char* cmd, bool use_vfork_if_available) {
3670 const char * argv[4] = {"sh", "-c", cmd, NULL};
3671
3672 // fork() in BsdThreads/NPTL is not async-safe. It needs to run
3673 // pthread_atfork handlers and reset pthread library. All we need is a
3674 // separate process to execve. Make a direct syscall to fork process.
3675 // On IA64 there's no fork syscall, we have to use fork() and hope for
3676 // the best...
3677 pid_t pid = fork();
3678
3679 if (pid < 0) {
3680 // fork failed
3681 return -1;
3682
3683 } else if (pid == 0) {
3684 // child process
3685
3686 // execve() in BsdThreads will call pthread_kill_other_threads_np()
3687 // first to kill every thread on the thread list. Because this list is
3688 // not reset by fork() (see notes above), execve() will instead kill
3689 // every thread in the parent process. We know this is the only thread
3690 // in the new process, so make a system call directly.
3691 // IA64 should use normal execve() from glibc to match the glibc fork()
3692 // above.
3693 execve("/bin/sh", (char* const*)argv, environ);
3694
3695 // execve failed
3696 _exit(-1);
3697
3698 } else {
3699 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
3700 // care about the actual exit code, for now.
3701
3702 int status;
3703
3704 // Wait for the child process to exit. This returns immediately if
3705 // the child has already exited. */
3706 while (waitpid(pid, &status, 0) < 0) {
3707 switch (errno) {
3708 case ECHILD: return 0;
3709 case EINTR: break;
3710 default: return -1;
3711 }
3712 }
3713
3714 if (WIFEXITED(status)) {
3715 // The child exited normally; get its exit code.
3716 return WEXITSTATUS(status);
3717 } else if (WIFSIGNALED(status)) {
3718 // The child exited because of a signal
3719 // The best value to return is 0x80 + signal number,
3720 // because that is what all Unix shells do, and because
3721 // it allows callers to distinguish between process exit and
3722 // process death by signal.
3723 return 0x80 + WTERMSIG(status);
3724 } else {
3725 // Unknown exit code; pass it through
3726 return status;
3727 }
3728 }
3729 }
3730
3731 // Get the kern.corefile setting, or otherwise the default path to the core file
3732 // Returns the length of the string
3733 int os::get_core_path(char* buffer, size_t bufferSize) {
3734 int n = 0;
3735 #ifdef __APPLE__
3736 char coreinfo[MAX_PATH];
3737 size_t sz = sizeof(coreinfo);
3738 int ret = sysctlbyname("kern.corefile", coreinfo, &sz, NULL, 0);
3739 if (ret == 0) {
3740 char *pid_pos = strstr(coreinfo, "%P");
3741 // skip over the "%P" to preserve any optional custom user pattern
3742 const char* tail = (pid_pos != NULL) ? (pid_pos + 2) : "";
3743
3744 if (pid_pos != NULL) {
3745 *pid_pos = '\0';
3746 n = jio_snprintf(buffer, bufferSize, "%s%d%s", coreinfo, os::current_process_id(), tail);
3747 } else {
3748 n = jio_snprintf(buffer, bufferSize, "%s", coreinfo);
3749 }
3750 } else
3751 #endif
3752 {
3753 n = jio_snprintf(buffer, bufferSize, "/cores/core.%d", os::current_process_id());
3754 }
3755 // Truncate if theoretical string was longer than bufferSize
3756 n = MIN2(n, (int)bufferSize);
3757
3758 return n;
3759 }
3760
3761 bool os::supports_map_sync() {
3762 return false;
3763 }
3764
3765 #ifndef PRODUCT
3766 void TestReserveMemorySpecial_test() {
3767 // No tests available for this platform
3768 }
3769 #endif
3770
3771 bool os::start_debugging(char *buf, int buflen) {
3772 int len = (int)strlen(buf);
3773 char *p = &buf[len];
3774
3775 jio_snprintf(p, buflen-len,
3776 "\n\n"
3777 "Do you want to debug the problem?\n\n"
3778 "To debug, run 'gdb /proc/%d/exe %d'; then switch to thread " INTX_FORMAT " (" INTPTR_FORMAT ")\n"
3779 "Enter 'yes' to launch gdb automatically (PATH must include gdb)\n"
3780 "Otherwise, press RETURN to abort...",
3781 os::current_process_id(), os::current_process_id(),
3782 os::current_thread_id(), os::current_thread_id());
3783
3784 bool yes = os::message_box("Unexpected Error", buf);
3785
3786 if (yes) {
3787 // yes, user asked VM to launch debugger
3788 jio_snprintf(buf, sizeof(buf), "gdb /proc/%d/exe %d",
3789 os::current_process_id(), os::current_process_id());
3790
3791 os::fork_and_exec(buf);
3792 yes = false;
3793 }
3794 return yes;
3795 }