1 /*
2 * Copyright (c) 1999, 2019, 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 "memory/allocation.inline.hpp"
37 #include "memory/filemap.hpp"
38 #include "oops/oop.inline.hpp"
39 #include "os_bsd.inline.hpp"
40 #include "os_posix.inline.hpp"
41 #include "os_share_bsd.hpp"
42 #include "prims/jniFastGetField.hpp"
43 #include "prims/jvm_misc.hpp"
44 #include "runtime/arguments.hpp"
45 #include "runtime/atomic.hpp"
46 #include "runtime/extendedPC.hpp"
47 #include "runtime/globals.hpp"
48 #include "runtime/interfaceSupport.inline.hpp"
49 #include "runtime/java.hpp"
50 #include "runtime/javaCalls.hpp"
51 #include "runtime/mutexLocker.hpp"
52 #include "runtime/objectMonitor.hpp"
53 #include "runtime/orderAccess.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 static pid_t _initial_pid = 0;
139
140 // Signal number used to suspend/resume a thread
141
142 // do not use any signal number less than SIGSEGV, see 4355769
143 static int SR_signum = SIGUSR2;
144 sigset_t SR_sigset;
145
146
147 ////////////////////////////////////////////////////////////////////////////////
148 // utility functions
149
150 static int SR_initialize();
151
152 julong os::available_memory() {
153 return Bsd::available_memory();
154 }
155
156 // available here means free
157 julong os::Bsd::available_memory() {
158 uint64_t available = physical_memory() >> 2;
159 #ifdef __APPLE__
160 mach_msg_type_number_t count = HOST_VM_INFO64_COUNT;
161 vm_statistics64_data_t vmstat;
162 kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64,
163 (host_info64_t)&vmstat, &count);
164 assert(kerr == KERN_SUCCESS,
165 "host_statistics64 failed - check mach_host_self() and count");
166 if (kerr == KERN_SUCCESS) {
167 available = vmstat.free_count * os::vm_page_size();
168 }
169 #endif
170 return available;
171 }
172
173 julong os::physical_memory() {
174 return Bsd::physical_memory();
175 }
176
177 // Return true if user is running as root.
178
179 bool os::have_special_privileges() {
180 static bool init = false;
181 static bool privileges = false;
182 if (!init) {
183 privileges = (getuid() != geteuid()) || (getgid() != getegid());
184 init = true;
185 }
186 return privileges;
187 }
188
189
190
191 // Cpu architecture string
192 #if defined(ZERO)
193 static char cpu_arch[] = ZERO_LIBARCH;
194 #elif defined(IA64)
195 static char cpu_arch[] = "ia64";
196 #elif defined(IA32)
197 static char cpu_arch[] = "i386";
198 #elif defined(AMD64)
199 static char cpu_arch[] = "amd64";
200 #elif defined(ARM)
201 static char cpu_arch[] = "arm";
202 #elif defined(PPC32)
203 static char cpu_arch[] = "ppc";
204 #elif defined(SPARC)
205 #ifdef _LP64
206 static char cpu_arch[] = "sparcv9";
207 #else
208 static char cpu_arch[] = "sparc";
209 #endif
210 #else
211 #error Add appropriate cpu_arch setting
212 #endif
213
214 // Compiler variant
215 #ifdef COMPILER2
216 #define COMPILER_VARIANT "server"
217 #else
218 #define COMPILER_VARIANT "client"
219 #endif
220
221
222 void os::Bsd::initialize_system_info() {
223 int mib[2];
224 size_t len;
225 int cpu_val;
226 julong mem_val;
227
228 // get processors count via hw.ncpus sysctl
229 mib[0] = CTL_HW;
230 mib[1] = HW_NCPU;
231 len = sizeof(cpu_val);
232 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) {
233 assert(len == sizeof(cpu_val), "unexpected data size");
234 set_processor_count(cpu_val);
235 } else {
236 set_processor_count(1); // fallback
237 }
238
239 // get physical memory via hw.memsize sysctl (hw.memsize is used
240 // since it returns a 64 bit value)
241 mib[0] = CTL_HW;
242
243 #if defined (HW_MEMSIZE) // Apple
244 mib[1] = HW_MEMSIZE;
245 #elif defined(HW_PHYSMEM) // Most of BSD
246 mib[1] = HW_PHYSMEM;
247 #elif defined(HW_REALMEM) // Old FreeBSD
248 mib[1] = HW_REALMEM;
249 #else
250 #error No ways to get physmem
251 #endif
252
253 len = sizeof(mem_val);
254 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) {
255 assert(len == sizeof(mem_val), "unexpected data size");
256 _physical_memory = mem_val;
257 } else {
258 _physical_memory = 256 * 1024 * 1024; // fallback (XXXBSD?)
259 }
260
261 #ifdef __OpenBSD__
262 {
263 // limit _physical_memory memory view on OpenBSD since
264 // datasize rlimit restricts us anyway.
265 struct rlimit limits;
266 getrlimit(RLIMIT_DATA, &limits);
267 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur);
268 }
269 #endif
270 }
271
272 #ifdef __APPLE__
273 static const char *get_home() {
274 const char *home_dir = ::getenv("HOME");
275 if ((home_dir == NULL) || (*home_dir == '\0')) {
276 struct passwd *passwd_info = getpwuid(geteuid());
277 if (passwd_info != NULL) {
278 home_dir = passwd_info->pw_dir;
279 }
280 }
281
282 return home_dir;
283 }
284 #endif
285
286 void os::init_system_properties_values() {
287 // The next steps are taken in the product version:
288 //
289 // Obtain the JAVA_HOME value from the location of libjvm.so.
290 // This library should be located at:
291 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so.
292 //
293 // If "/jre/lib/" appears at the right place in the path, then we
294 // assume libjvm.so is installed in a JDK and we use this path.
295 //
296 // Otherwise exit with message: "Could not create the Java virtual machine."
297 //
298 // The following extra steps are taken in the debugging version:
299 //
300 // If "/jre/lib/" does NOT appear at the right place in the path
301 // instead of exit check for $JAVA_HOME environment variable.
302 //
303 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>,
304 // then we append a fake suffix "hotspot/libjvm.so" to this path so
305 // it looks like libjvm.so is installed there
306 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so.
307 //
308 // Otherwise exit.
309 //
310 // Important note: if the location of libjvm.so changes this
311 // code needs to be changed accordingly.
312
313 // See ld(1):
314 // The linker uses the following search paths to locate required
315 // shared libraries:
316 // 1: ...
317 // ...
318 // 7: The default directories, normally /lib and /usr/lib.
319 #ifndef DEFAULT_LIBPATH
320 #ifndef OVERRIDE_LIBPATH
321 #define DEFAULT_LIBPATH "/lib:/usr/lib"
322 #else
323 #define DEFAULT_LIBPATH OVERRIDE_LIBPATH
324 #endif
325 #endif
326
327 // Base path of extensions installed on the system.
328 #define SYS_EXT_DIR "/usr/java/packages"
329 #define EXTENSIONS_DIR "/lib/ext"
330
331 #ifndef __APPLE__
332
333 // Buffer that fits several sprintfs.
334 // Note that the space for the colon and the trailing null are provided
335 // by the nulls included by the sizeof operator.
336 const size_t bufsize =
337 MAX2((size_t)MAXPATHLEN, // For dll_dir & friends.
338 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + sizeof(SYS_EXT_DIR) + sizeof(EXTENSIONS_DIR)); // extensions dir
339 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
340
341 // sysclasspath, java_home, dll_dir
342 {
343 char *pslash;
344 os::jvm_path(buf, bufsize);
345
346 // Found the full path to libjvm.so.
347 // Now cut the path to <java_home>/jre if we can.
348 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
349 pslash = strrchr(buf, '/');
350 if (pslash != NULL) {
351 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
352 }
353 Arguments::set_dll_dir(buf);
354
355 if (pslash != NULL) {
356 pslash = strrchr(buf, '/');
357 if (pslash != NULL) {
358 *pslash = '\0'; // Get rid of /<arch>.
359 pslash = strrchr(buf, '/');
360 if (pslash != NULL) {
361 *pslash = '\0'; // Get rid of /lib.
362 }
363 }
364 }
365 Arguments::set_java_home(buf);
366 if (!set_boot_path('/', ':')) {
367 vm_exit_during_initialization("Failed setting boot class path.", NULL);
368 }
369 }
370
371 // Where to look for native libraries.
372 //
373 // Note: Due to a legacy implementation, most of the library path
374 // is set in the launcher. This was to accomodate linking restrictions
375 // on legacy Bsd implementations (which are no longer supported).
376 // Eventually, all the library path setting will be done here.
377 //
378 // However, to prevent the proliferation of improperly built native
379 // libraries, the new path component /usr/java/packages is added here.
380 // Eventually, all the library path setting will be done here.
381 {
382 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
383 // should always exist (until the legacy problem cited above is
384 // addressed).
385 const char *v = ::getenv("LD_LIBRARY_PATH");
386 const char *v_colon = ":";
387 if (v == NULL) { v = ""; v_colon = ""; }
388 // That's +1 for the colon and +1 for the trailing '\0'.
389 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char,
390 strlen(v) + 1 +
391 sizeof(SYS_EXT_DIR) + sizeof("/lib/") + strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH) + 1,
392 mtInternal);
393 sprintf(ld_library_path, "%s%s" SYS_EXT_DIR "/lib/%s:" DEFAULT_LIBPATH, v, v_colon, cpu_arch);
394 Arguments::set_library_path(ld_library_path);
395 FREE_C_HEAP_ARRAY(char, ld_library_path);
396 }
397
398 // Extensions directories.
399 sprintf(buf, "%s" EXTENSIONS_DIR ":" SYS_EXT_DIR EXTENSIONS_DIR, Arguments::get_java_home());
400 Arguments::set_ext_dirs(buf);
401
402 FREE_C_HEAP_ARRAY(char, buf);
403
404 #else // __APPLE__
405
406 #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions"
407 #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java"
408
409 const char *user_home_dir = get_home();
410 // The null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir.
411 size_t system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) +
412 sizeof(SYS_EXTENSIONS_DIRS);
413
414 // Buffer that fits several sprintfs.
415 // Note that the space for the colon and the trailing null are provided
416 // by the nulls included by the sizeof operator.
417 const size_t bufsize =
418 MAX2((size_t)MAXPATHLEN, // for dll_dir & friends.
419 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + system_ext_size); // extensions dir
420 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
421
422 // sysclasspath, java_home, dll_dir
423 {
424 char *pslash;
425 os::jvm_path(buf, bufsize);
426
427 // Found the full path to libjvm.so.
428 // Now cut the path to <java_home>/jre if we can.
429 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
430 pslash = strrchr(buf, '/');
431 if (pslash != NULL) {
432 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
433 }
434 #ifdef STATIC_BUILD
435 strcat(buf, "/lib");
436 #endif
437
438 Arguments::set_dll_dir(buf);
439
440 if (pslash != NULL) {
441 pslash = strrchr(buf, '/');
442 if (pslash != NULL) {
443 *pslash = '\0'; // Get rid of /lib.
444 }
445 }
446 Arguments::set_java_home(buf);
447 set_boot_path('/', ':');
448 }
449
450 // Where to look for native libraries.
451 //
452 // Note: Due to a legacy implementation, most of the library path
453 // is set in the launcher. This was to accomodate linking restrictions
454 // on legacy Bsd implementations (which are no longer supported).
455 // Eventually, all the library path setting will be done here.
456 //
457 // However, to prevent the proliferation of improperly built native
458 // libraries, the new path component /usr/java/packages is added here.
459 // Eventually, all the library path setting will be done here.
460 {
461 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
462 // should always exist (until the legacy problem cited above is
463 // addressed).
464 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code
465 // can specify a directory inside an app wrapper
466 const char *l = ::getenv("JAVA_LIBRARY_PATH");
467 const char *l_colon = ":";
468 if (l == NULL) { l = ""; l_colon = ""; }
469
470 const char *v = ::getenv("DYLD_LIBRARY_PATH");
471 const char *v_colon = ":";
472 if (v == NULL) { v = ""; v_colon = ""; }
473
474 // Apple's Java6 has "." at the beginning of java.library.path.
475 // OpenJDK on Windows has "." at the end of java.library.path.
476 // OpenJDK on Linux and Solaris don't have "." in java.library.path
477 // at all. To ease the transition from Apple's Java6 to OpenJDK7,
478 // "." is appended to the end of java.library.path. Yes, this
479 // could cause a change in behavior, but Apple's Java6 behavior
480 // can be achieved by putting "." at the beginning of the
481 // JAVA_LIBRARY_PATH environment variable.
482 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char,
483 strlen(v) + 1 + strlen(l) + 1 +
484 system_ext_size + 3,
485 mtInternal);
486 sprintf(ld_library_path, "%s%s%s%s%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS ":.",
487 v, v_colon, l, l_colon, user_home_dir);
488 Arguments::set_library_path(ld_library_path);
489 FREE_C_HEAP_ARRAY(char, ld_library_path);
490 }
491
492 // Extensions directories.
493 //
494 // Note that the space for the colon and the trailing null are provided
495 // by the nulls included by the sizeof operator (so actually one byte more
496 // than necessary is allocated).
497 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS,
498 user_home_dir, Arguments::get_java_home());
499 Arguments::set_ext_dirs(buf);
500
501 FREE_C_HEAP_ARRAY(char, buf);
502
503 #undef SYS_EXTENSIONS_DIR
504 #undef SYS_EXTENSIONS_DIRS
505
506 #endif // __APPLE__
507
508 #undef SYS_EXT_DIR
509 #undef EXTENSIONS_DIR
510 }
511
512 ////////////////////////////////////////////////////////////////////////////////
513 // breakpoint support
514
515 void os::breakpoint() {
516 BREAKPOINT;
517 }
518
519 extern "C" void breakpoint() {
520 // use debugger to set breakpoint here
521 }
522
523 ////////////////////////////////////////////////////////////////////////////////
524 // signal support
525
526 debug_only(static bool signal_sets_initialized = false);
527 static sigset_t unblocked_sigs, vm_sigs;
528
529 void os::Bsd::signal_sets_init() {
530 // Should also have an assertion stating we are still single-threaded.
531 assert(!signal_sets_initialized, "Already initialized");
532 // Fill in signals that are necessarily unblocked for all threads in
533 // the VM. Currently, we unblock the following signals:
534 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
535 // by -Xrs (=ReduceSignalUsage));
536 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
537 // other threads. The "ReduceSignalUsage" boolean tells us not to alter
538 // the dispositions or masks wrt these signals.
539 // Programs embedding the VM that want to use the above signals for their
540 // own purposes must, at this time, use the "-Xrs" option to prevent
541 // interference with shutdown hooks and BREAK_SIGNAL thread dumping.
542 // (See bug 4345157, and other related bugs).
543 // In reality, though, unblocking these signals is really a nop, since
544 // these signals are not blocked by default.
545 sigemptyset(&unblocked_sigs);
546 sigaddset(&unblocked_sigs, SIGILL);
547 sigaddset(&unblocked_sigs, SIGSEGV);
548 sigaddset(&unblocked_sigs, SIGBUS);
549 sigaddset(&unblocked_sigs, SIGFPE);
550 sigaddset(&unblocked_sigs, SR_signum);
551
552 if (!ReduceSignalUsage) {
553 if (!os::Posix::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
554 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
555
556 }
557 if (!os::Posix::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
558 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
559 }
560 if (!os::Posix::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
561 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
562 }
563 }
564 // Fill in signals that are blocked by all but the VM thread.
565 sigemptyset(&vm_sigs);
566 if (!ReduceSignalUsage) {
567 sigaddset(&vm_sigs, BREAK_SIGNAL);
568 }
569 debug_only(signal_sets_initialized = true);
570
571 }
572
573 // These are signals that are unblocked while a thread is running Java.
574 // (For some reason, they get blocked by default.)
575 sigset_t* os::Bsd::unblocked_signals() {
576 assert(signal_sets_initialized, "Not initialized");
577 return &unblocked_sigs;
578 }
579
580 // These are the signals that are blocked while a (non-VM) thread is
581 // running Java. Only the VM thread handles these signals.
582 sigset_t* os::Bsd::vm_signals() {
583 assert(signal_sets_initialized, "Not initialized");
584 return &vm_sigs;
585 }
586
587 void os::Bsd::hotspot_sigmask(Thread* thread) {
588
589 //Save caller's signal mask before setting VM signal mask
590 sigset_t caller_sigmask;
591 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
592
593 OSThread* osthread = thread->osthread();
594 osthread->set_caller_sigmask(caller_sigmask);
595
596 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL);
597
598 if (!ReduceSignalUsage) {
599 if (thread->is_VM_thread()) {
600 // Only the VM thread handles BREAK_SIGNAL ...
601 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
602 } else {
603 // ... all other threads block BREAK_SIGNAL
604 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
605 }
606 }
607 }
608
609
610 //////////////////////////////////////////////////////////////////////////////
611 // create new thread
612
613 #ifdef __APPLE__
614 // library handle for calling objc_registerThreadWithCollector()
615 // without static linking to the libobjc library
616 #define OBJC_LIB "/usr/lib/libobjc.dylib"
617 #define OBJC_GCREGISTER "objc_registerThreadWithCollector"
618 typedef void (*objc_registerThreadWithCollector_t)();
619 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction;
620 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL;
621 #endif
622
623 #ifdef __APPLE__
624 static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) {
625 // Additional thread_id used to correlate threads in SA
626 thread_identifier_info_data_t m_ident_info;
627 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT;
628
629 thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO,
630 (thread_info_t) &m_ident_info, &count);
631
632 return m_ident_info.thread_id;
633 }
634 #endif
635
636 // Thread start routine for all newly created threads
637 static void *thread_native_entry(Thread *thread) {
638
639 thread->record_stack_base_and_size();
640
641 // Try to randomize the cache line index of hot stack frames.
642 // This helps when threads of the same stack traces evict each other's
643 // cache lines. The threads can be either from the same JVM instance, or
644 // from different JVM instances. The benefit is especially true for
645 // processors with hyperthreading technology.
646 static int counter = 0;
647 int pid = os::current_process_id();
648 alloca(((pid ^ counter++) & 7) * 128);
649
650 thread->initialize_thread_current();
651
652 OSThread* osthread = thread->osthread();
653 Monitor* sync = osthread->startThread_lock();
654
655 osthread->set_thread_id(os::Bsd::gettid());
656
657 log_info(os, thread)("Thread is alive (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").",
658 os::current_thread_id(), (uintx) pthread_self());
659
660 #ifdef __APPLE__
661 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
662 guarantee(unique_thread_id != 0, "unique thread id was not found");
663 osthread->set_unique_thread_id(unique_thread_id);
664 #endif
665 // initialize signal mask for this thread
666 os::Bsd::hotspot_sigmask(thread);
667
668 // initialize floating point control register
669 os::Bsd::init_thread_fpu_state();
670
671 #ifdef __APPLE__
672 // register thread with objc gc
673 if (objc_registerThreadWithCollectorFunction != NULL) {
674 objc_registerThreadWithCollectorFunction();
675 }
676 #endif
677
678 // handshaking with parent thread
679 {
680 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
681
682 // notify parent thread
683 osthread->set_state(INITIALIZED);
684 sync->notify_all();
685
686 // wait until os::start_thread()
687 while (osthread->get_state() == INITIALIZED) {
688 sync->wait(Mutex::_no_safepoint_check_flag);
689 }
690 }
691
692 // call one more level start routine
693 thread->call_run();
694
695 // Note: at this point the thread object may already have deleted itself.
696 // Prevent dereferencing it from here on out.
697 thread = NULL;
698
699 log_info(os, thread)("Thread finished (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").",
700 os::current_thread_id(), (uintx) pthread_self());
701
702 return 0;
703 }
704
705 bool os::create_thread(Thread* thread, ThreadType thr_type,
706 size_t req_stack_size) {
707 assert(thread->osthread() == NULL, "caller responsible");
708
709 // Allocate the OSThread object
710 OSThread* osthread = new OSThread(NULL, NULL);
711 if (osthread == NULL) {
712 return false;
713 }
714
715 // set the correct thread state
716 osthread->set_thread_type(thr_type);
717
718 // Initial state is ALLOCATED but not INITIALIZED
719 osthread->set_state(ALLOCATED);
720
721 thread->set_osthread(osthread);
722
723 // init thread attributes
724 pthread_attr_t attr;
725 pthread_attr_init(&attr);
726 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
727
728 // calculate stack size if it's not specified by caller
729 size_t stack_size = os::Posix::get_initial_stack_size(thr_type, req_stack_size);
730 int status = pthread_attr_setstacksize(&attr, stack_size);
731 assert_status(status == 0, status, "pthread_attr_setstacksize");
732
733 ThreadState state;
734
735 {
736 pthread_t tid;
737 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) thread_native_entry, thread);
738
739 char buf[64];
740 if (ret == 0) {
741 log_info(os, thread)("Thread started (pthread id: " UINTX_FORMAT ", attributes: %s). ",
742 (uintx) tid, os::Posix::describe_pthread_attr(buf, sizeof(buf), &attr));
743 } else {
744 log_warning(os, thread)("Failed to start thread - pthread_create failed (%s) for attributes: %s.",
745 os::errno_name(ret), os::Posix::describe_pthread_attr(buf, sizeof(buf), &attr));
746 }
747
748 pthread_attr_destroy(&attr);
749
750 if (ret != 0) {
751 // Need to clean up stuff we've allocated so far
752 thread->set_osthread(NULL);
753 delete osthread;
754 return false;
755 }
756
757 // Store pthread info into the OSThread
758 osthread->set_pthread_id(tid);
759
760 // Wait until child thread is either initialized or aborted
761 {
762 Monitor* sync_with_child = osthread->startThread_lock();
763 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
764 while ((state = osthread->get_state()) == ALLOCATED) {
765 sync_with_child->wait(Mutex::_no_safepoint_check_flag);
766 }
767 }
768
769 }
770
771 // Aborted due to thread limit being reached
772 if (state == ZOMBIE) {
773 thread->set_osthread(NULL);
774 delete osthread;
775 return false;
776 }
777
778 // The thread is returned suspended (in state INITIALIZED),
779 // and is started higher up in the call chain
780 assert(state == INITIALIZED, "race condition");
781 return true;
782 }
783
784 /////////////////////////////////////////////////////////////////////////////
785 // attach existing thread
786
787 // bootstrap the main thread
788 bool os::create_main_thread(JavaThread* thread) {
789 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
790 return create_attached_thread(thread);
791 }
792
793 bool os::create_attached_thread(JavaThread* thread) {
794 #ifdef ASSERT
795 thread->verify_not_published();
796 #endif
797
798 // Allocate the OSThread object
799 OSThread* osthread = new OSThread(NULL, NULL);
800
801 if (osthread == NULL) {
802 return false;
803 }
804
805 osthread->set_thread_id(os::Bsd::gettid());
806
807 // Store pthread info into the OSThread
808 #ifdef __APPLE__
809 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
810 guarantee(unique_thread_id != 0, "just checking");
811 osthread->set_unique_thread_id(unique_thread_id);
812 #endif
813 osthread->set_pthread_id(::pthread_self());
814
815 // initialize floating point control register
816 os::Bsd::init_thread_fpu_state();
817
818 // Initial thread state is RUNNABLE
819 osthread->set_state(RUNNABLE);
820
821 thread->set_osthread(osthread);
822
823 // initialize signal mask for this thread
824 // and save the caller's signal mask
825 os::Bsd::hotspot_sigmask(thread);
826
827 log_info(os, thread)("Thread attached (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").",
828 os::current_thread_id(), (uintx) pthread_self());
829
830 return true;
831 }
832
833 void os::pd_start_thread(Thread* thread) {
834 OSThread * osthread = thread->osthread();
835 assert(osthread->get_state() != INITIALIZED, "just checking");
836 Monitor* sync_with_child = osthread->startThread_lock();
837 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
838 sync_with_child->notify();
839 }
840
841 // Free Bsd resources related to the OSThread
842 void os::free_thread(OSThread* osthread) {
843 assert(osthread != NULL, "osthread not set");
844
845 // We are told to free resources of the argument thread,
846 // but we can only really operate on the current thread.
847 assert(Thread::current()->osthread() == osthread,
848 "os::free_thread but not current thread");
849
850 // Restore caller's signal mask
851 sigset_t sigmask = osthread->caller_sigmask();
852 pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
853
854 delete osthread;
855 }
856
857 ////////////////////////////////////////////////////////////////////////////////
858 // time support
859
860 // Time since start-up in seconds to a fine granularity.
861 // Used by VMSelfDestructTimer and the MemProfiler.
862 double os::elapsedTime() {
863
864 return ((double)os::elapsed_counter()) / os::elapsed_frequency();
865 }
866
867 jlong os::elapsed_counter() {
868 return javaTimeNanos() - initial_time_count;
869 }
870
871 jlong os::elapsed_frequency() {
872 return NANOSECS_PER_SEC; // nanosecond resolution
873 }
874
875 bool os::supports_vtime() { return true; }
876 bool os::enable_vtime() { return false; }
877 bool os::vtime_enabled() { return false; }
878
879 double os::elapsedVTime() {
880 // better than nothing, but not much
881 return elapsedTime();
882 }
883
884 jlong os::javaTimeMillis() {
885 timeval time;
886 int status = gettimeofday(&time, NULL);
887 assert(status != -1, "bsd error");
888 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
889 }
890
891 void os::javaTimeSystemUTC(jlong &seconds, jlong &nanos) {
892 timeval time;
893 int status = gettimeofday(&time, NULL);
894 assert(status != -1, "bsd error");
895 seconds = jlong(time.tv_sec);
896 nanos = jlong(time.tv_usec) * 1000;
897 }
898
899 #ifndef __APPLE__
900 #ifndef CLOCK_MONOTONIC
901 #define CLOCK_MONOTONIC (1)
902 #endif
903 #endif
904
905 #ifdef __APPLE__
906 void os::Bsd::clock_init() {
907 mach_timebase_info(&_timebase_info);
908 }
909 #else
910 void os::Bsd::clock_init() {
911 struct timespec res;
912 struct timespec tp;
913 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
914 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) {
915 // yes, monotonic clock is supported
916 _clock_gettime = ::clock_gettime;
917 }
918 }
919 #endif
920
921
922
923 #ifdef __APPLE__
924
925 jlong os::javaTimeNanos() {
926 const uint64_t tm = mach_absolute_time();
927 const uint64_t now = (tm * Bsd::_timebase_info.numer) / Bsd::_timebase_info.denom;
928 const uint64_t prev = Bsd::_max_abstime;
929 if (now <= prev) {
930 return prev; // same or retrograde time;
931 }
932 const uint64_t obsv = Atomic::cmpxchg(now, &Bsd::_max_abstime, prev);
933 assert(obsv >= prev, "invariant"); // Monotonicity
934 // If the CAS succeeded then we're done and return "now".
935 // If the CAS failed and the observed value "obsv" is >= now then
936 // we should return "obsv". If the CAS failed and now > obsv > prv then
937 // some other thread raced this thread and installed a new value, in which case
938 // we could either (a) retry the entire operation, (b) retry trying to install now
939 // or (c) just return obsv. We use (c). No loop is required although in some cases
940 // we might discard a higher "now" value in deference to a slightly lower but freshly
941 // installed obsv value. That's entirely benign -- it admits no new orderings compared
942 // to (a) or (b) -- and greatly reduces coherence traffic.
943 // We might also condition (c) on the magnitude of the delta between obsv and now.
944 // Avoiding excessive CAS operations to hot RW locations is critical.
945 // See https://blogs.oracle.com/dave/entry/cas_and_cache_trivia_invalidate
946 return (prev == obsv) ? now : obsv;
947 }
948
949 #else // __APPLE__
950
951 jlong os::javaTimeNanos() {
952 if (os::supports_monotonic_clock()) {
953 struct timespec tp;
954 int status = Bsd::_clock_gettime(CLOCK_MONOTONIC, &tp);
955 assert(status == 0, "gettime error");
956 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
957 return result;
958 } else {
959 timeval time;
960 int status = gettimeofday(&time, NULL);
961 assert(status != -1, "bsd error");
962 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
963 return 1000 * usecs;
964 }
965 }
966
967 #endif // __APPLE__
968
969 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
970 if (os::supports_monotonic_clock()) {
971 info_ptr->max_value = ALL_64_BITS;
972
973 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
974 info_ptr->may_skip_backward = false; // not subject to resetting or drifting
975 info_ptr->may_skip_forward = false; // not subject to resetting or drifting
976 } else {
977 // gettimeofday - based on time in seconds since the Epoch thus does not wrap
978 info_ptr->max_value = ALL_64_BITS;
979
980 // gettimeofday is a real time clock so it skips
981 info_ptr->may_skip_backward = true;
982 info_ptr->may_skip_forward = true;
983 }
984
985 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
986 }
987
988 // Return the real, user, and system times in seconds from an
989 // arbitrary fixed point in the past.
990 bool os::getTimesSecs(double* process_real_time,
991 double* process_user_time,
992 double* process_system_time) {
993 struct tms ticks;
994 clock_t real_ticks = times(&ticks);
995
996 if (real_ticks == (clock_t) (-1)) {
997 return false;
998 } else {
999 double ticks_per_second = (double) clock_tics_per_sec;
1000 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1001 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1002 *process_real_time = ((double) real_ticks) / ticks_per_second;
1003
1004 return true;
1005 }
1006 }
1007
1008
1009 char * os::local_time_string(char *buf, size_t buflen) {
1010 struct tm t;
1011 time_t long_time;
1012 time(&long_time);
1013 localtime_r(&long_time, &t);
1014 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1015 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1016 t.tm_hour, t.tm_min, t.tm_sec);
1017 return buf;
1018 }
1019
1020 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
1021 return localtime_r(clock, res);
1022 }
1023
1024 ////////////////////////////////////////////////////////////////////////////////
1025 // runtime exit support
1026
1027 // Note: os::shutdown() might be called very early during initialization, or
1028 // called from signal handler. Before adding something to os::shutdown(), make
1029 // sure it is async-safe and can handle partially initialized VM.
1030 void os::shutdown() {
1031
1032 // allow PerfMemory to attempt cleanup of any persistent resources
1033 perfMemory_exit();
1034
1035 // needs to remove object in file system
1036 AttachListener::abort();
1037
1038 // flush buffered output, finish log files
1039 ostream_abort();
1040
1041 // Check for abort hook
1042 abort_hook_t abort_hook = Arguments::abort_hook();
1043 if (abort_hook != NULL) {
1044 abort_hook();
1045 }
1046
1047 }
1048
1049 // Note: os::abort() might be called very early during initialization, or
1050 // called from signal handler. Before adding something to os::abort(), make
1051 // sure it is async-safe and can handle partially initialized VM.
1052 void os::abort(bool dump_core, void* siginfo, const void* context) {
1053 os::shutdown();
1054 if (dump_core) {
1055 #ifndef PRODUCT
1056 fdStream out(defaultStream::output_fd());
1057 out.print_raw("Current thread is ");
1058 char buf[16];
1059 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
1060 out.print_raw_cr(buf);
1061 out.print_raw_cr("Dumping core ...");
1062 #endif
1063 ::abort(); // dump core
1064 }
1065
1066 ::exit(1);
1067 }
1068
1069 // Die immediately, no exit hook, no abort hook, no cleanup.
1070 void os::die() {
1071 // _exit() on BsdThreads only kills current thread
1072 ::abort();
1073 }
1074
1075 // Information of current thread in variety of formats
1076 pid_t os::Bsd::gettid() {
1077 int retval = -1;
1078
1079 #ifdef __APPLE__ //XNU kernel
1080 // despite the fact mach port is actually not a thread id use it
1081 // instead of syscall(SYS_thread_selfid) as it certainly fits to u4
1082 retval = ::pthread_mach_thread_np(::pthread_self());
1083 guarantee(retval != 0, "just checking");
1084 return retval;
1085
1086 #else
1087 #ifdef __FreeBSD__
1088 retval = syscall(SYS_thr_self);
1089 #else
1090 #ifdef __OpenBSD__
1091 retval = syscall(SYS_getthrid);
1092 #else
1093 #ifdef __NetBSD__
1094 retval = (pid_t) syscall(SYS__lwp_self);
1095 #endif
1096 #endif
1097 #endif
1098 #endif
1099
1100 if (retval == -1) {
1101 return getpid();
1102 }
1103 }
1104
1105 intx os::current_thread_id() {
1106 #ifdef __APPLE__
1107 return (intx)::pthread_mach_thread_np(::pthread_self());
1108 #else
1109 return (intx)::pthread_self();
1110 #endif
1111 }
1112
1113 int os::current_process_id() {
1114
1115 // Under the old bsd thread library, bsd gives each thread
1116 // its own process id. Because of this each thread will return
1117 // a different pid if this method were to return the result
1118 // of getpid(2). Bsd provides no api that returns the pid
1119 // of the launcher thread for the vm. This implementation
1120 // returns a unique pid, the pid of the launcher thread
1121 // that starts the vm 'process'.
1122
1123 // Under the NPTL, getpid() returns the same pid as the
1124 // launcher thread rather than a unique pid per thread.
1125 // Use gettid() if you want the old pre NPTL behaviour.
1126
1127 // if you are looking for the result of a call to getpid() that
1128 // returns a unique pid for the calling thread, then look at the
1129 // OSThread::thread_id() method in osThread_bsd.hpp file
1130
1131 return (int)(_initial_pid ? _initial_pid : getpid());
1132 }
1133
1134 // DLL functions
1135
1136 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1137
1138 // This must be hard coded because it's the system's temporary
1139 // directory not the java application's temp directory, ala java.io.tmpdir.
1140 #ifdef __APPLE__
1141 // macosx has a secure per-user temporary directory
1142 char temp_path_storage[PATH_MAX];
1143 const char* os::get_temp_directory() {
1144 static char *temp_path = NULL;
1145 if (temp_path == NULL) {
1146 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
1147 if (pathSize == 0 || pathSize > PATH_MAX) {
1148 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
1149 }
1150 temp_path = temp_path_storage;
1151 }
1152 return temp_path;
1153 }
1154 #else // __APPLE__
1155 const char* os::get_temp_directory() { return "/tmp"; }
1156 #endif // __APPLE__
1157
1158 // check if addr is inside libjvm.so
1159 bool os::address_is_in_vm(address addr) {
1160 static address libjvm_base_addr;
1161 Dl_info dlinfo;
1162
1163 if (libjvm_base_addr == NULL) {
1164 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) {
1165 libjvm_base_addr = (address)dlinfo.dli_fbase;
1166 }
1167 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1168 }
1169
1170 if (dladdr((void *)addr, &dlinfo) != 0) {
1171 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1172 }
1173
1174 return false;
1175 }
1176
1177
1178 #define MACH_MAXSYMLEN 256
1179
1180 bool os::dll_address_to_function_name(address addr, char *buf,
1181 int buflen, int *offset,
1182 bool demangle) {
1183 // buf is not optional, but offset is optional
1184 assert(buf != NULL, "sanity check");
1185
1186 Dl_info dlinfo;
1187 char localbuf[MACH_MAXSYMLEN];
1188
1189 if (dladdr((void*)addr, &dlinfo) != 0) {
1190 // see if we have a matching symbol
1191 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) {
1192 if (!(demangle && Decoder::demangle(dlinfo.dli_sname, buf, buflen))) {
1193 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1194 }
1195 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1196 return true;
1197 }
1198 // no matching symbol so try for just file info
1199 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) {
1200 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1201 buf, buflen, offset, dlinfo.dli_fname, demangle)) {
1202 return true;
1203 }
1204 }
1205
1206 // Handle non-dynamic manually:
1207 if (dlinfo.dli_fbase != NULL &&
1208 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset,
1209 dlinfo.dli_fbase)) {
1210 if (!(demangle && Decoder::demangle(localbuf, buf, buflen))) {
1211 jio_snprintf(buf, buflen, "%s", localbuf);
1212 }
1213 return true;
1214 }
1215 }
1216 buf[0] = '\0';
1217 if (offset != NULL) *offset = -1;
1218 return false;
1219 }
1220
1221 // ported from solaris version
1222 bool os::dll_address_to_library_name(address addr, char* buf,
1223 int buflen, int* offset) {
1224 // buf is not optional, but offset is optional
1225 assert(buf != NULL, "sanity check");
1226
1227 Dl_info dlinfo;
1228
1229 if (dladdr((void*)addr, &dlinfo) != 0) {
1230 if (dlinfo.dli_fname != NULL) {
1231 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1232 }
1233 if (dlinfo.dli_fbase != NULL && offset != NULL) {
1234 *offset = addr - (address)dlinfo.dli_fbase;
1235 }
1236 return true;
1237 }
1238
1239 buf[0] = '\0';
1240 if (offset) *offset = -1;
1241 return false;
1242 }
1243
1244 // Loads .dll/.so and
1245 // in case of error it checks if .dll/.so was built for the
1246 // same architecture as Hotspot is running on
1247
1248 #ifdef __APPLE__
1249 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1250 #ifdef STATIC_BUILD
1251 return os::get_default_process_handle();
1252 #else
1253 void * result= ::dlopen(filename, RTLD_LAZY);
1254 if (result != NULL) {
1255 // Successful loading
1256 return result;
1257 }
1258
1259 // Read system error message into ebuf
1260 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1261 ebuf[ebuflen-1]='\0';
1262
1263 return NULL;
1264 #endif // STATIC_BUILD
1265 }
1266 #else
1267 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1268 #ifdef STATIC_BUILD
1269 return os::get_default_process_handle();
1270 #else
1271 void * result= ::dlopen(filename, RTLD_LAZY);
1272 if (result != NULL) {
1273 // Successful loading
1274 return result;
1275 }
1276
1277 Elf32_Ehdr elf_head;
1278
1279 // Read system error message into ebuf
1280 // It may or may not be overwritten below
1281 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1282 ebuf[ebuflen-1]='\0';
1283 int diag_msg_max_length=ebuflen-strlen(ebuf);
1284 char* diag_msg_buf=ebuf+strlen(ebuf);
1285
1286 if (diag_msg_max_length==0) {
1287 // No more space in ebuf for additional diagnostics message
1288 return NULL;
1289 }
1290
1291
1292 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1293
1294 if (file_descriptor < 0) {
1295 // Can't open library, report dlerror() message
1296 return NULL;
1297 }
1298
1299 bool failed_to_read_elf_head=
1300 (sizeof(elf_head)!=
1301 (::read(file_descriptor, &elf_head,sizeof(elf_head))));
1302
1303 ::close(file_descriptor);
1304 if (failed_to_read_elf_head) {
1305 // file i/o error - report dlerror() msg
1306 return NULL;
1307 }
1308
1309 typedef struct {
1310 Elf32_Half code; // Actual value as defined in elf.h
1311 Elf32_Half compat_class; // Compatibility of archs at VM's sense
1312 char elf_class; // 32 or 64 bit
1313 char endianess; // MSB or LSB
1314 char* name; // String representation
1315 } arch_t;
1316
1317 #ifndef EM_486
1318 #define EM_486 6 /* Intel 80486 */
1319 #endif
1320
1321 #ifndef EM_MIPS_RS3_LE
1322 #define EM_MIPS_RS3_LE 10 /* MIPS */
1323 #endif
1324
1325 #ifndef EM_PPC64
1326 #define EM_PPC64 21 /* PowerPC64 */
1327 #endif
1328
1329 #ifndef EM_S390
1330 #define EM_S390 22 /* IBM System/390 */
1331 #endif
1332
1333 #ifndef EM_IA_64
1334 #define EM_IA_64 50 /* HP/Intel IA-64 */
1335 #endif
1336
1337 #ifndef EM_X86_64
1338 #define EM_X86_64 62 /* AMD x86-64 */
1339 #endif
1340
1341 static const arch_t arch_array[]={
1342 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1343 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1344 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
1345 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
1346 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1347 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1348 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
1349 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
1350 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
1351 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"},
1352 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
1353 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
1354 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
1355 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
1356 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
1357 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
1358 };
1359
1360 #if (defined IA32)
1361 static Elf32_Half running_arch_code=EM_386;
1362 #elif (defined AMD64)
1363 static Elf32_Half running_arch_code=EM_X86_64;
1364 #elif (defined IA64)
1365 static Elf32_Half running_arch_code=EM_IA_64;
1366 #elif (defined __sparc) && (defined _LP64)
1367 static Elf32_Half running_arch_code=EM_SPARCV9;
1368 #elif (defined __sparc) && (!defined _LP64)
1369 static Elf32_Half running_arch_code=EM_SPARC;
1370 #elif (defined __powerpc64__)
1371 static Elf32_Half running_arch_code=EM_PPC64;
1372 #elif (defined __powerpc__)
1373 static Elf32_Half running_arch_code=EM_PPC;
1374 #elif (defined ARM)
1375 static Elf32_Half running_arch_code=EM_ARM;
1376 #elif (defined S390)
1377 static Elf32_Half running_arch_code=EM_S390;
1378 #elif (defined ALPHA)
1379 static Elf32_Half running_arch_code=EM_ALPHA;
1380 #elif (defined MIPSEL)
1381 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
1382 #elif (defined PARISC)
1383 static Elf32_Half running_arch_code=EM_PARISC;
1384 #elif (defined MIPS)
1385 static Elf32_Half running_arch_code=EM_MIPS;
1386 #elif (defined M68K)
1387 static Elf32_Half running_arch_code=EM_68K;
1388 #else
1389 #error Method os::dll_load requires that one of following is defined:\
1390 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
1391 #endif
1392
1393 // Identify compatability class for VM's architecture and library's architecture
1394 // Obtain string descriptions for architectures
1395
1396 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
1397 int running_arch_index=-1;
1398
1399 for (unsigned int i=0; i < ARRAY_SIZE(arch_array); i++) {
1400 if (running_arch_code == arch_array[i].code) {
1401 running_arch_index = i;
1402 }
1403 if (lib_arch.code == arch_array[i].code) {
1404 lib_arch.compat_class = arch_array[i].compat_class;
1405 lib_arch.name = arch_array[i].name;
1406 }
1407 }
1408
1409 assert(running_arch_index != -1,
1410 "Didn't find running architecture code (running_arch_code) in arch_array");
1411 if (running_arch_index == -1) {
1412 // Even though running architecture detection failed
1413 // we may still continue with reporting dlerror() message
1414 return NULL;
1415 }
1416
1417 if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
1418 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
1419 return NULL;
1420 }
1421
1422 #ifndef S390
1423 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
1424 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
1425 return NULL;
1426 }
1427 #endif // !S390
1428
1429 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
1430 if (lib_arch.name!=NULL) {
1431 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1432 " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
1433 lib_arch.name, arch_array[running_arch_index].name);
1434 } else {
1435 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1436 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
1437 lib_arch.code,
1438 arch_array[running_arch_index].name);
1439 }
1440 }
1441
1442 return NULL;
1443 #endif // STATIC_BUILD
1444 }
1445 #endif // !__APPLE__
1446
1447 void* os::get_default_process_handle() {
1448 #ifdef __APPLE__
1449 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY
1450 // to avoid finding unexpected symbols on second (or later)
1451 // loads of a library.
1452 return (void*)::dlopen(NULL, RTLD_FIRST);
1453 #else
1454 return (void*)::dlopen(NULL, RTLD_LAZY);
1455 #endif
1456 }
1457
1458 // XXX: Do we need a lock around this as per Linux?
1459 void* os::dll_lookup(void* handle, const char* name) {
1460 return dlsym(handle, name);
1461 }
1462
1463 int _print_dll_info_cb(const char * name, address base_address, address top_address, void * param) {
1464 outputStream * out = (outputStream *) param;
1465 out->print_cr(INTPTR_FORMAT " \t%s", (intptr_t)base_address, name);
1466 return 0;
1467 }
1468
1469 void os::print_dll_info(outputStream *st) {
1470 st->print_cr("Dynamic libraries:");
1471 if (get_loaded_modules_info(_print_dll_info_cb, (void *)st)) {
1472 st->print_cr("Error: Cannot print dynamic libraries.");
1473 }
1474 }
1475
1476 int os::get_loaded_modules_info(os::LoadedModulesCallbackFunc callback, void *param) {
1477 #ifdef RTLD_DI_LINKMAP
1478 Dl_info dli;
1479 void *handle;
1480 Link_map *map;
1481 Link_map *p;
1482
1483 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 ||
1484 dli.dli_fname == NULL) {
1485 return 1;
1486 }
1487 handle = dlopen(dli.dli_fname, RTLD_LAZY);
1488 if (handle == NULL) {
1489 return 1;
1490 }
1491 dlinfo(handle, RTLD_DI_LINKMAP, &map);
1492 if (map == NULL) {
1493 dlclose(handle);
1494 return 1;
1495 }
1496
1497 while (map->l_prev != NULL)
1498 map = map->l_prev;
1499
1500 while (map != NULL) {
1501 // Value for top_address is returned as 0 since we don't have any information about module size
1502 if (callback(map->l_name, (address)map->l_addr, (address)0, param)) {
1503 dlclose(handle);
1504 return 1;
1505 }
1506 map = map->l_next;
1507 }
1508
1509 dlclose(handle);
1510 #elif defined(__APPLE__)
1511 for (uint32_t i = 1; i < _dyld_image_count(); i++) {
1512 // Value for top_address is returned as 0 since we don't have any information about module size
1513 if (callback(_dyld_get_image_name(i), (address)_dyld_get_image_header(i), (address)0, param)) {
1514 return 1;
1515 }
1516 }
1517 return 0;
1518 #else
1519 return 1;
1520 #endif
1521 }
1522
1523 void os::get_summary_os_info(char* buf, size_t buflen) {
1524 // These buffers are small because we want this to be brief
1525 // and not use a lot of stack while generating the hs_err file.
1526 char os[100];
1527 size_t size = sizeof(os);
1528 int mib_kern[] = { CTL_KERN, KERN_OSTYPE };
1529 if (sysctl(mib_kern, 2, os, &size, NULL, 0) < 0) {
1530 #ifdef __APPLE__
1531 strncpy(os, "Darwin", sizeof(os));
1532 #elif __OpenBSD__
1533 strncpy(os, "OpenBSD", sizeof(os));
1534 #else
1535 strncpy(os, "BSD", sizeof(os));
1536 #endif
1537 }
1538
1539 char release[100];
1540 size = sizeof(release);
1541 int mib_release[] = { CTL_KERN, KERN_OSRELEASE };
1542 if (sysctl(mib_release, 2, release, &size, NULL, 0) < 0) {
1543 // if error, leave blank
1544 strncpy(release, "", sizeof(release));
1545 }
1546 snprintf(buf, buflen, "%s %s", os, release);
1547 }
1548
1549 void os::print_os_info_brief(outputStream* st) {
1550 os::Posix::print_uname_info(st);
1551 }
1552
1553 void os::print_os_info(outputStream* st) {
1554 st->print("OS:");
1555
1556 os::Posix::print_uname_info(st);
1557
1558 os::Posix::print_rlimit_info(st);
1559
1560 os::Posix::print_load_average(st);
1561 }
1562
1563 void os::pd_print_cpu_info(outputStream* st, char* buf, size_t buflen) {
1564 // Nothing to do for now.
1565 }
1566
1567 void os::get_summary_cpu_info(char* buf, size_t buflen) {
1568 unsigned int mhz;
1569 size_t size = sizeof(mhz);
1570 int mib[] = { CTL_HW, HW_CPU_FREQ };
1571 if (sysctl(mib, 2, &mhz, &size, NULL, 0) < 0) {
1572 mhz = 1; // looks like an error but can be divided by
1573 } else {
1574 mhz /= 1000000; // reported in millions
1575 }
1576
1577 char model[100];
1578 size = sizeof(model);
1579 int mib_model[] = { CTL_HW, HW_MODEL };
1580 if (sysctl(mib_model, 2, model, &size, NULL, 0) < 0) {
1581 strncpy(model, cpu_arch, sizeof(model));
1582 }
1583
1584 char machine[100];
1585 size = sizeof(machine);
1586 int mib_machine[] = { CTL_HW, HW_MACHINE };
1587 if (sysctl(mib_machine, 2, machine, &size, NULL, 0) < 0) {
1588 strncpy(machine, "", sizeof(machine));
1589 }
1590
1591 snprintf(buf, buflen, "%s %s %d MHz", model, machine, mhz);
1592 }
1593
1594 void os::print_memory_info(outputStream* st) {
1595 xsw_usage swap_usage;
1596 size_t size = sizeof(swap_usage);
1597
1598 st->print("Memory:");
1599 st->print(" %dk page", os::vm_page_size()>>10);
1600
1601 st->print(", physical " UINT64_FORMAT "k",
1602 os::physical_memory() >> 10);
1603 st->print("(" UINT64_FORMAT "k free)",
1604 os::available_memory() >> 10);
1605
1606 if(sysctlbyname("vm.swapusage", &swap_usage, &size, NULL, 0) == 0) {
1607 if (size >= offsetof(xsw_usage, xsu_used)) {
1608 st->print(", swap " UINT64_FORMAT "k",
1609 ((julong) swap_usage.xsu_total) >> 10);
1610 st->print("(" UINT64_FORMAT "k free)",
1611 ((julong) swap_usage.xsu_avail) >> 10);
1612 }
1613 }
1614
1615 st->cr();
1616 }
1617
1618 static void print_signal_handler(outputStream* st, int sig,
1619 char* buf, size_t buflen);
1620
1621 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1622 st->print_cr("Signal Handlers:");
1623 print_signal_handler(st, SIGSEGV, buf, buflen);
1624 print_signal_handler(st, SIGBUS , buf, buflen);
1625 print_signal_handler(st, SIGFPE , buf, buflen);
1626 print_signal_handler(st, SIGPIPE, buf, buflen);
1627 print_signal_handler(st, SIGXFSZ, buf, buflen);
1628 print_signal_handler(st, SIGILL , buf, buflen);
1629 print_signal_handler(st, SR_signum, buf, buflen);
1630 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1631 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1632 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1633 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1634 }
1635
1636 static char saved_jvm_path[MAXPATHLEN] = {0};
1637
1638 // Find the full path to the current module, libjvm
1639 void os::jvm_path(char *buf, jint buflen) {
1640 // Error checking.
1641 if (buflen < MAXPATHLEN) {
1642 assert(false, "must use a large-enough buffer");
1643 buf[0] = '\0';
1644 return;
1645 }
1646 // Lazy resolve the path to current module.
1647 if (saved_jvm_path[0] != 0) {
1648 strcpy(buf, saved_jvm_path);
1649 return;
1650 }
1651
1652 char dli_fname[MAXPATHLEN];
1653 bool ret = dll_address_to_library_name(
1654 CAST_FROM_FN_PTR(address, os::jvm_path),
1655 dli_fname, sizeof(dli_fname), NULL);
1656 assert(ret, "cannot locate libjvm");
1657 char *rp = NULL;
1658 if (ret && dli_fname[0] != '\0') {
1659 rp = os::Posix::realpath(dli_fname, buf, buflen);
1660 }
1661 if (rp == NULL) {
1662 return;
1663 }
1664
1665 if (Arguments::sun_java_launcher_is_altjvm()) {
1666 // Support for the java launcher's '-XXaltjvm=<path>' option. Typical
1667 // value for buf is "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so"
1668 // or "<JAVA_HOME>/jre/lib/<vmtype>/libjvm.dylib". If "/jre/lib/"
1669 // appears at the right place in the string, then assume we are
1670 // installed in a JDK and we're done. Otherwise, check for a
1671 // JAVA_HOME environment variable and construct a path to the JVM
1672 // being overridden.
1673
1674 const char *p = buf + strlen(buf) - 1;
1675 for (int count = 0; p > buf && count < 5; ++count) {
1676 for (--p; p > buf && *p != '/'; --p)
1677 /* empty */ ;
1678 }
1679
1680 if (strncmp(p, "/jre/lib/", 9) != 0) {
1681 // Look for JAVA_HOME in the environment.
1682 char* java_home_var = ::getenv("JAVA_HOME");
1683 if (java_home_var != NULL && java_home_var[0] != 0) {
1684 char* jrelib_p;
1685 int len;
1686
1687 // Check the current module name "libjvm"
1688 p = strrchr(buf, '/');
1689 assert(strstr(p, "/libjvm") == p, "invalid library name");
1690
1691 rp = os::Posix::realpath(java_home_var, buf, buflen);
1692 if (rp == NULL) {
1693 return;
1694 }
1695
1696 // determine if this is a legacy image or modules image
1697 // modules image doesn't have "jre" subdirectory
1698 len = strlen(buf);
1699 assert(len < buflen, "Ran out of buffer space");
1700 jrelib_p = buf + len;
1701
1702 // Add the appropriate library subdir
1703 snprintf(jrelib_p, buflen-len, "/jre/lib");
1704 if (0 != access(buf, F_OK)) {
1705 snprintf(jrelib_p, buflen-len, "/lib");
1706 }
1707
1708 // Add the appropriate client or server subdir
1709 len = strlen(buf);
1710 jrelib_p = buf + len;
1711 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
1712 if (0 != access(buf, F_OK)) {
1713 snprintf(jrelib_p, buflen-len, "%s", "");
1714 }
1715
1716 // If the path exists within JAVA_HOME, add the JVM library name
1717 // to complete the path to JVM being overridden. Otherwise fallback
1718 // to the path to the current library.
1719 if (0 == access(buf, F_OK)) {
1720 // Use current module name "libjvm"
1721 len = strlen(buf);
1722 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
1723 } else {
1724 // Fall back to path of current library
1725 rp = os::Posix::realpath(dli_fname, buf, buflen);
1726 if (rp == NULL) {
1727 return;
1728 }
1729 }
1730 }
1731 }
1732 }
1733
1734 strncpy(saved_jvm_path, buf, MAXPATHLEN);
1735 saved_jvm_path[MAXPATHLEN - 1] = '\0';
1736 }
1737
1738 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1739 // no prefix required, not even "_"
1740 }
1741
1742 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1743 // no suffix required
1744 }
1745
1746 ////////////////////////////////////////////////////////////////////////////////
1747 // sun.misc.Signal support
1748
1749 static volatile jint sigint_count = 0;
1750
1751 static void UserHandler(int sig, void *siginfo, void *context) {
1752 // 4511530 - sem_post is serialized and handled by the manager thread. When
1753 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
1754 // don't want to flood the manager thread with sem_post requests.
1755 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1) {
1756 return;
1757 }
1758
1759 // Ctrl-C is pressed during error reporting, likely because the error
1760 // handler fails to abort. Let VM die immediately.
1761 if (sig == SIGINT && VMError::is_error_reported()) {
1762 os::die();
1763 }
1764
1765 os::signal_notify(sig);
1766 }
1767
1768 void* os::user_handler() {
1769 return CAST_FROM_FN_PTR(void*, UserHandler);
1770 }
1771
1772 extern "C" {
1773 typedef void (*sa_handler_t)(int);
1774 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1775 }
1776
1777 void* os::signal(int signal_number, void* handler) {
1778 struct sigaction sigAct, oldSigAct;
1779
1780 sigfillset(&(sigAct.sa_mask));
1781 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
1782 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1783
1784 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1785 // -1 means registration failed
1786 return (void *)-1;
1787 }
1788
1789 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1790 }
1791
1792 void os::signal_raise(int signal_number) {
1793 ::raise(signal_number);
1794 }
1795
1796 // The following code is moved from os.cpp for making this
1797 // code platform specific, which it is by its very nature.
1798
1799 // Will be modified when max signal is changed to be dynamic
1800 int os::sigexitnum_pd() {
1801 return NSIG;
1802 }
1803
1804 // a counter for each possible signal value
1805 static volatile jint pending_signals[NSIG+1] = { 0 };
1806 static Semaphore* sig_sem = NULL;
1807
1808 static void jdk_misc_signal_init() {
1809 // Initialize signal structures
1810 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
1811
1812 // Initialize signal semaphore
1813 sig_sem = new Semaphore();
1814 }
1815
1816 void os::signal_notify(int sig) {
1817 if (sig_sem != NULL) {
1818 Atomic::inc(&pending_signals[sig]);
1819 sig_sem->signal();
1820 } else {
1821 // Signal thread is not created with ReduceSignalUsage and jdk_misc_signal_init
1822 // initialization isn't called.
1823 assert(ReduceSignalUsage, "signal semaphore should be created");
1824 }
1825 }
1826
1827 static int check_pending_signals() {
1828 Atomic::store(0, &sigint_count);
1829 for (;;) {
1830 for (int i = 0; i < NSIG + 1; i++) {
1831 jint n = pending_signals[i];
1832 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
1833 return i;
1834 }
1835 }
1836 JavaThread *thread = JavaThread::current();
1837 ThreadBlockInVM tbivm(thread);
1838
1839 bool threadIsSuspended;
1840 do {
1841 thread->set_suspend_equivalent();
1842 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
1843 sig_sem->wait();
1844
1845 // were we externally suspended while we were waiting?
1846 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
1847 if (threadIsSuspended) {
1848 // The semaphore has been incremented, but while we were waiting
1849 // another thread suspended us. We don't want to continue running
1850 // while suspended because that would surprise the thread that
1851 // suspended us.
1852 sig_sem->signal();
1853
1854 thread->java_suspend_self();
1855 }
1856 } while (threadIsSuspended);
1857 }
1858 }
1859
1860 int os::signal_wait() {
1861 return check_pending_signals();
1862 }
1863
1864 ////////////////////////////////////////////////////////////////////////////////
1865 // Virtual Memory
1866
1867 int os::vm_page_size() {
1868 // Seems redundant as all get out
1869 assert(os::Bsd::page_size() != -1, "must call os::init");
1870 return os::Bsd::page_size();
1871 }
1872
1873 // Solaris allocates memory by pages.
1874 int os::vm_allocation_granularity() {
1875 assert(os::Bsd::page_size() != -1, "must call os::init");
1876 return os::Bsd::page_size();
1877 }
1878
1879 // Rationale behind this function:
1880 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
1881 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
1882 // samples for JITted code. Here we create private executable mapping over the code cache
1883 // and then we can use standard (well, almost, as mapping can change) way to provide
1884 // info for the reporting script by storing timestamp and location of symbol
1885 void bsd_wrap_code(char* base, size_t size) {
1886 static volatile jint cnt = 0;
1887
1888 if (!UseOprofile) {
1889 return;
1890 }
1891
1892 char buf[PATH_MAX + 1];
1893 int num = Atomic::add(1, &cnt);
1894
1895 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
1896 os::get_temp_directory(), os::current_process_id(), num);
1897 unlink(buf);
1898
1899 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
1900
1901 if (fd != -1) {
1902 off_t rv = ::lseek(fd, size-2, SEEK_SET);
1903 if (rv != (off_t)-1) {
1904 if (::write(fd, "", 1) == 1) {
1905 mmap(base, size,
1906 PROT_READ|PROT_WRITE|PROT_EXEC,
1907 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
1908 }
1909 }
1910 ::close(fd);
1911 unlink(buf);
1912 }
1913 }
1914
1915 static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
1916 int err) {
1917 warning("INFO: os::commit_memory(" INTPTR_FORMAT ", " SIZE_FORMAT
1918 ", %d) failed; error='%s' (errno=%d)", (intptr_t)addr, size, exec,
1919 os::errno_name(err), err);
1920 }
1921
1922 // NOTE: Bsd kernel does not really reserve the pages for us.
1923 // All it does is to check if there are enough free pages
1924 // left at the time of mmap(). This could be a potential
1925 // problem.
1926 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
1927 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
1928 #ifdef __OpenBSD__
1929 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
1930 if (::mprotect(addr, size, prot) == 0) {
1931 return true;
1932 }
1933 #else
1934 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
1935 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
1936 if (res != (uintptr_t) MAP_FAILED) {
1937 return true;
1938 }
1939 #endif
1940
1941 // Warn about any commit errors we see in non-product builds just
1942 // in case mmap() doesn't work as described on the man page.
1943 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);)
1944
1945 return false;
1946 }
1947
1948 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
1949 bool exec) {
1950 // alignment_hint is ignored on this OS
1951 return pd_commit_memory(addr, size, exec);
1952 }
1953
1954 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
1955 const char* mesg) {
1956 assert(mesg != NULL, "mesg must be specified");
1957 if (!pd_commit_memory(addr, size, exec)) {
1958 // add extra info in product mode for vm_exit_out_of_memory():
1959 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
1960 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, "%s", mesg);
1961 }
1962 }
1963
1964 void os::pd_commit_memory_or_exit(char* addr, size_t size,
1965 size_t alignment_hint, bool exec,
1966 const char* mesg) {
1967 // alignment_hint is ignored on this OS
1968 pd_commit_memory_or_exit(addr, size, exec, mesg);
1969 }
1970
1971 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
1972 }
1973
1974 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
1975 ::madvise(addr, bytes, MADV_DONTNEED);
1976 }
1977
1978 void os::numa_make_global(char *addr, size_t bytes) {
1979 }
1980
1981 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
1982 }
1983
1984 bool os::numa_topology_changed() { return false; }
1985
1986 size_t os::numa_get_groups_num() {
1987 return 1;
1988 }
1989
1990 int os::numa_get_group_id() {
1991 return 0;
1992 }
1993
1994 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
1995 if (size > 0) {
1996 ids[0] = 0;
1997 return 1;
1998 }
1999 return 0;
2000 }
2001
2002 bool os::get_page_info(char *start, page_info* info) {
2003 return false;
2004 }
2005
2006 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2007 return end;
2008 }
2009
2010
2011 bool os::pd_uncommit_memory(char* addr, size_t size) {
2012 #ifdef __OpenBSD__
2013 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2014 return ::mprotect(addr, size, PROT_NONE) == 0;
2015 #else
2016 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
2017 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
2018 return res != (uintptr_t) MAP_FAILED;
2019 #endif
2020 }
2021
2022 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2023 return os::commit_memory(addr, size, !ExecMem);
2024 }
2025
2026 // If this is a growable mapping, remove the guard pages entirely by
2027 // munmap()ping them. If not, just call uncommit_memory().
2028 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2029 return os::uncommit_memory(addr, size);
2030 }
2031
2032 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2033 // at 'requested_addr'. If there are existing memory mappings at the same
2034 // location, however, they will be overwritten. If 'fixed' is false,
2035 // 'requested_addr' is only treated as a hint, the return value may or
2036 // may not start from the requested address. Unlike Bsd mmap(), this
2037 // function returns NULL to indicate failure.
2038 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2039 char * addr;
2040 int flags;
2041
2042 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2043 if (fixed) {
2044 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2045 flags |= MAP_FIXED;
2046 }
2047
2048 // Map reserved/uncommitted pages PROT_NONE so we fail early if we
2049 // touch an uncommitted page. Otherwise, the read/write might
2050 // succeed if we have enough swap space to back the physical page.
2051 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE,
2052 flags, -1, 0);
2053
2054 return addr == MAP_FAILED ? NULL : addr;
2055 }
2056
2057 static int anon_munmap(char * addr, size_t size) {
2058 return ::munmap(addr, size) == 0;
2059 }
2060
2061 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
2062 size_t alignment_hint) {
2063 return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2064 }
2065
2066 bool os::pd_release_memory(char* addr, size_t size) {
2067 return anon_munmap(addr, size);
2068 }
2069
2070 static bool bsd_mprotect(char* addr, size_t size, int prot) {
2071 // Bsd wants the mprotect address argument to be page aligned.
2072 char* bottom = (char*)align_down((intptr_t)addr, os::Bsd::page_size());
2073
2074 // According to SUSv3, mprotect() should only be used with mappings
2075 // established by mmap(), and mmap() always maps whole pages. Unaligned
2076 // 'addr' likely indicates problem in the VM (e.g. trying to change
2077 // protection of malloc'ed or statically allocated memory). Check the
2078 // caller if you hit this assert.
2079 assert(addr == bottom, "sanity check");
2080
2081 size = align_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2082 return ::mprotect(bottom, size, prot) == 0;
2083 }
2084
2085 // Set protections specified
2086 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2087 bool is_committed) {
2088 unsigned int p = 0;
2089 switch (prot) {
2090 case MEM_PROT_NONE: p = PROT_NONE; break;
2091 case MEM_PROT_READ: p = PROT_READ; break;
2092 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
2093 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2094 default:
2095 ShouldNotReachHere();
2096 }
2097 // is_committed is unused.
2098 return bsd_mprotect(addr, bytes, p);
2099 }
2100
2101 bool os::guard_memory(char* addr, size_t size) {
2102 return bsd_mprotect(addr, size, PROT_NONE);
2103 }
2104
2105 bool os::unguard_memory(char* addr, size_t size) {
2106 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
2107 }
2108
2109 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
2110 return false;
2111 }
2112
2113 // Large page support
2114
2115 static size_t _large_page_size = 0;
2116
2117 void os::large_page_init() {
2118 }
2119
2120
2121 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) {
2122 fatal("os::reserve_memory_special should not be called on BSD.");
2123 return NULL;
2124 }
2125
2126 bool os::release_memory_special(char* base, size_t bytes) {
2127 fatal("os::release_memory_special should not be called on BSD.");
2128 return false;
2129 }
2130
2131 size_t os::large_page_size() {
2132 return _large_page_size;
2133 }
2134
2135 bool os::can_commit_large_page_memory() {
2136 // Does not matter, we do not support huge pages.
2137 return false;
2138 }
2139
2140 bool os::can_execute_large_page_memory() {
2141 // Does not matter, we do not support huge pages.
2142 return false;
2143 }
2144
2145 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr, int file_desc) {
2146 assert(file_desc >= 0, "file_desc is not valid");
2147 char* result = pd_attempt_reserve_memory_at(bytes, requested_addr);
2148 if (result != NULL) {
2149 if (replace_existing_mapping_with_file_mapping(result, bytes, file_desc) == NULL) {
2150 vm_exit_during_initialization(err_msg("Error in mapping Java heap at the given filesystem directory"));
2151 }
2152 }
2153 return result;
2154 }
2155
2156 // Reserve memory at an arbitrary address, only if that area is
2157 // available (and not reserved for something else).
2158
2159 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2160 const int max_tries = 10;
2161 char* base[max_tries];
2162 size_t size[max_tries];
2163 const size_t gap = 0x000000;
2164
2165 // Assert only that the size is a multiple of the page size, since
2166 // that's all that mmap requires, and since that's all we really know
2167 // about at this low abstraction level. If we need higher alignment,
2168 // we can either pass an alignment to this method or verify alignment
2169 // in one of the methods further up the call chain. See bug 5044738.
2170 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2171
2172 // Repeatedly allocate blocks until the block is allocated at the
2173 // right spot.
2174
2175 // Bsd mmap allows caller to pass an address as hint; give it a try first,
2176 // if kernel honors the hint then we can return immediately.
2177 char * addr = anon_mmap(requested_addr, bytes, false);
2178 if (addr == requested_addr) {
2179 return requested_addr;
2180 }
2181
2182 if (addr != NULL) {
2183 // mmap() is successful but it fails to reserve at the requested address
2184 anon_munmap(addr, bytes);
2185 }
2186
2187 int i;
2188 for (i = 0; i < max_tries; ++i) {
2189 base[i] = reserve_memory(bytes);
2190
2191 if (base[i] != NULL) {
2192 // Is this the block we wanted?
2193 if (base[i] == requested_addr) {
2194 size[i] = bytes;
2195 break;
2196 }
2197
2198 // Does this overlap the block we wanted? Give back the overlapped
2199 // parts and try again.
2200
2201 size_t top_overlap = requested_addr + (bytes + gap) - base[i];
2202 if (top_overlap >= 0 && top_overlap < bytes) {
2203 unmap_memory(base[i], top_overlap);
2204 base[i] += top_overlap;
2205 size[i] = bytes - top_overlap;
2206 } else {
2207 size_t bottom_overlap = base[i] + bytes - requested_addr;
2208 if (bottom_overlap >= 0 && bottom_overlap < bytes) {
2209 unmap_memory(requested_addr, bottom_overlap);
2210 size[i] = bytes - bottom_overlap;
2211 } else {
2212 size[i] = bytes;
2213 }
2214 }
2215 }
2216 }
2217
2218 // Give back the unused reserved pieces.
2219
2220 for (int j = 0; j < i; ++j) {
2221 if (base[j] != NULL) {
2222 unmap_memory(base[j], size[j]);
2223 }
2224 }
2225
2226 if (i < max_tries) {
2227 return requested_addr;
2228 } else {
2229 return NULL;
2230 }
2231 }
2232
2233 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2234 void os::infinite_sleep() {
2235 while (true) { // sleep forever ...
2236 ::sleep(100); // ... 100 seconds at a time
2237 }
2238 }
2239
2240 // Used to convert frequent JVM_Yield() to nops
2241 bool os::dont_yield() {
2242 return DontYieldALot;
2243 }
2244
2245 void os::naked_yield() {
2246 sched_yield();
2247 }
2248
2249 ////////////////////////////////////////////////////////////////////////////////
2250 // thread priority support
2251
2252 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2253 // only supports dynamic priority, static priority must be zero. For real-time
2254 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
2255 // However, for large multi-threaded applications, SCHED_RR is not only slower
2256 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2257 // of 5 runs - Sep 2005).
2258 //
2259 // The following code actually changes the niceness of kernel-thread/LWP. It
2260 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
2261 // not the entire user process, and user level threads are 1:1 mapped to kernel
2262 // threads. It has always been the case, but could change in the future. For
2263 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2264 // It is only used when ThreadPriorityPolicy=1 and may require system level permission
2265 // (e.g., root privilege or CAP_SYS_NICE capability).
2266
2267 #if !defined(__APPLE__)
2268 int os::java_to_os_priority[CriticalPriority + 1] = {
2269 19, // 0 Entry should never be used
2270
2271 0, // 1 MinPriority
2272 3, // 2
2273 6, // 3
2274
2275 10, // 4
2276 15, // 5 NormPriority
2277 18, // 6
2278
2279 21, // 7
2280 25, // 8
2281 28, // 9 NearMaxPriority
2282
2283 31, // 10 MaxPriority
2284
2285 31 // 11 CriticalPriority
2286 };
2287 #else
2288 // Using Mach high-level priority assignments
2289 int os::java_to_os_priority[CriticalPriority + 1] = {
2290 0, // 0 Entry should never be used (MINPRI_USER)
2291
2292 27, // 1 MinPriority
2293 28, // 2
2294 29, // 3
2295
2296 30, // 4
2297 31, // 5 NormPriority (BASEPRI_DEFAULT)
2298 32, // 6
2299
2300 33, // 7
2301 34, // 8
2302 35, // 9 NearMaxPriority
2303
2304 36, // 10 MaxPriority
2305
2306 36 // 11 CriticalPriority
2307 };
2308 #endif
2309
2310 static int prio_init() {
2311 if (ThreadPriorityPolicy == 1) {
2312 if (geteuid() != 0) {
2313 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
2314 warning("-XX:ThreadPriorityPolicy=1 may require system level permission, " \
2315 "e.g., being the root user. If the necessary permission is not " \
2316 "possessed, changes to priority will be silently ignored.");
2317 }
2318 }
2319 }
2320 if (UseCriticalJavaThreadPriority) {
2321 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2322 }
2323 return 0;
2324 }
2325
2326 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2327 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) return OS_OK;
2328
2329 #ifdef __OpenBSD__
2330 // OpenBSD pthread_setprio starves low priority threads
2331 return OS_OK;
2332 #elif defined(__FreeBSD__)
2333 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2334 return (ret == 0) ? OS_OK : OS_ERR;
2335 #elif defined(__APPLE__) || defined(__NetBSD__)
2336 struct sched_param sp;
2337 int policy;
2338
2339 if (pthread_getschedparam(thread->osthread()->pthread_id(), &policy, &sp) != 0) {
2340 return OS_ERR;
2341 }
2342
2343 sp.sched_priority = newpri;
2344 if (pthread_setschedparam(thread->osthread()->pthread_id(), policy, &sp) != 0) {
2345 return OS_ERR;
2346 }
2347
2348 return OS_OK;
2349 #else
2350 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2351 return (ret == 0) ? OS_OK : OS_ERR;
2352 #endif
2353 }
2354
2355 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2356 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) {
2357 *priority_ptr = java_to_os_priority[NormPriority];
2358 return OS_OK;
2359 }
2360
2361 errno = 0;
2362 #if defined(__OpenBSD__) || defined(__FreeBSD__)
2363 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2364 #elif defined(__APPLE__) || defined(__NetBSD__)
2365 int policy;
2366 struct sched_param sp;
2367
2368 int res = pthread_getschedparam(thread->osthread()->pthread_id(), &policy, &sp);
2369 if (res != 0) {
2370 *priority_ptr = -1;
2371 return OS_ERR;
2372 } else {
2373 *priority_ptr = sp.sched_priority;
2374 return OS_OK;
2375 }
2376 #else
2377 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2378 #endif
2379 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2380 }
2381
2382 ////////////////////////////////////////////////////////////////////////////////
2383 // suspend/resume support
2384
2385 // The low-level signal-based suspend/resume support is a remnant from the
2386 // old VM-suspension that used to be for java-suspension, safepoints etc,
2387 // within hotspot. Currently used by JFR's OSThreadSampler
2388 //
2389 // The remaining code is greatly simplified from the more general suspension
2390 // code that used to be used.
2391 //
2392 // The protocol is quite simple:
2393 // - suspend:
2394 // - sends a signal to the target thread
2395 // - polls the suspend state of the osthread using a yield loop
2396 // - target thread signal handler (SR_handler) sets suspend state
2397 // and blocks in sigsuspend until continued
2398 // - resume:
2399 // - sets target osthread state to continue
2400 // - sends signal to end the sigsuspend loop in the SR_handler
2401 //
2402 // Note that the SR_lock plays no role in this suspend/resume protocol,
2403 // but is checked for NULL in SR_handler as a thread termination indicator.
2404 // The SR_lock is, however, used by JavaThread::java_suspend()/java_resume() APIs.
2405 //
2406 // Note that resume_clear_context() and suspend_save_context() are needed
2407 // by SR_handler(), so that fetch_frame_from_ucontext() works,
2408 // which in part is used by:
2409 // - Forte Analyzer: AsyncGetCallTrace()
2410 // - StackBanging: get_frame_at_stack_banging_point()
2411
2412 static void resume_clear_context(OSThread *osthread) {
2413 osthread->set_ucontext(NULL);
2414 osthread->set_siginfo(NULL);
2415 }
2416
2417 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2418 osthread->set_ucontext(context);
2419 osthread->set_siginfo(siginfo);
2420 }
2421
2422 // Handler function invoked when a thread's execution is suspended or
2423 // resumed. We have to be careful that only async-safe functions are
2424 // called here (Note: most pthread functions are not async safe and
2425 // should be avoided.)
2426 //
2427 // Note: sigwait() is a more natural fit than sigsuspend() from an
2428 // interface point of view, but sigwait() prevents the signal hander
2429 // from being run. libpthread would get very confused by not having
2430 // its signal handlers run and prevents sigwait()'s use with the
2431 // mutex granting granting signal.
2432 //
2433 // Currently only ever called on the VMThread or JavaThread
2434 //
2435 #ifdef __APPLE__
2436 static OSXSemaphore sr_semaphore;
2437 #else
2438 static PosixSemaphore sr_semaphore;
2439 #endif
2440
2441 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2442 // Save and restore errno to avoid confusing native code with EINTR
2443 // after sigsuspend.
2444 int old_errno = errno;
2445
2446 Thread* thread = Thread::current_or_null_safe();
2447 assert(thread != NULL, "Missing current thread in SR_handler");
2448
2449 // On some systems we have seen signal delivery get "stuck" until the signal
2450 // mask is changed as part of thread termination. Check that the current thread
2451 // has not already terminated (via SR_lock()) - else the following assertion
2452 // will fail because the thread is no longer a JavaThread as the ~JavaThread
2453 // destructor has completed.
2454
2455 if (thread->SR_lock() == NULL) {
2456 return;
2457 }
2458
2459 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
2460
2461 OSThread* osthread = thread->osthread();
2462
2463 os::SuspendResume::State current = osthread->sr.state();
2464 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
2465 suspend_save_context(osthread, siginfo, context);
2466
2467 // attempt to switch the state, we assume we had a SUSPEND_REQUEST
2468 os::SuspendResume::State state = osthread->sr.suspended();
2469 if (state == os::SuspendResume::SR_SUSPENDED) {
2470 sigset_t suspend_set; // signals for sigsuspend()
2471
2472 // get current set of blocked signals and unblock resume signal
2473 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2474 sigdelset(&suspend_set, SR_signum);
2475
2476 sr_semaphore.signal();
2477 // wait here until we are resumed
2478 while (1) {
2479 sigsuspend(&suspend_set);
2480
2481 os::SuspendResume::State result = osthread->sr.running();
2482 if (result == os::SuspendResume::SR_RUNNING) {
2483 sr_semaphore.signal();
2484 break;
2485 } else if (result != os::SuspendResume::SR_SUSPENDED) {
2486 ShouldNotReachHere();
2487 }
2488 }
2489
2490 } else if (state == os::SuspendResume::SR_RUNNING) {
2491 // request was cancelled, continue
2492 } else {
2493 ShouldNotReachHere();
2494 }
2495
2496 resume_clear_context(osthread);
2497 } else if (current == os::SuspendResume::SR_RUNNING) {
2498 // request was cancelled, continue
2499 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
2500 // ignore
2501 } else {
2502 // ignore
2503 }
2504
2505 errno = old_errno;
2506 }
2507
2508
2509 static int SR_initialize() {
2510 struct sigaction act;
2511 char *s;
2512 // Get signal number to use for suspend/resume
2513 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2514 int sig = ::strtol(s, 0, 10);
2515 if (sig > MAX2(SIGSEGV, SIGBUS) && // See 4355769.
2516 sig < NSIG) { // Must be legal signal and fit into sigflags[].
2517 SR_signum = sig;
2518 } else {
2519 warning("You set _JAVA_SR_SIGNUM=%d. It must be in range [%d, %d]. Using %d instead.",
2520 sig, MAX2(SIGSEGV, SIGBUS)+1, NSIG-1, SR_signum);
2521 }
2522 }
2523
2524 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2525 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2526
2527 sigemptyset(&SR_sigset);
2528 sigaddset(&SR_sigset, SR_signum);
2529
2530 // Set up signal handler for suspend/resume
2531 act.sa_flags = SA_RESTART|SA_SIGINFO;
2532 act.sa_handler = (void (*)(int)) SR_handler;
2533
2534 // SR_signum is blocked by default.
2535 // 4528190 - We also need to block pthread restart signal (32 on all
2536 // supported Bsd platforms). Note that BsdThreads need to block
2537 // this signal for all threads to work properly. So we don't have
2538 // to use hard-coded signal number when setting up the mask.
2539 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2540
2541 if (sigaction(SR_signum, &act, 0) == -1) {
2542 return -1;
2543 }
2544
2545 // Save signal flag
2546 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2547 return 0;
2548 }
2549
2550 static int sr_notify(OSThread* osthread) {
2551 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2552 assert_status(status == 0, status, "pthread_kill");
2553 return status;
2554 }
2555
2556 // "Randomly" selected value for how long we want to spin
2557 // before bailing out on suspending a thread, also how often
2558 // we send a signal to a thread we want to resume
2559 static const int RANDOMLY_LARGE_INTEGER = 1000000;
2560 static const int RANDOMLY_LARGE_INTEGER2 = 100;
2561
2562 // returns true on success and false on error - really an error is fatal
2563 // but this seems the normal response to library errors
2564 static bool do_suspend(OSThread* osthread) {
2565 assert(osthread->sr.is_running(), "thread should be running");
2566 assert(!sr_semaphore.trywait(), "semaphore has invalid state");
2567
2568 // mark as suspended and send signal
2569 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
2570 // failed to switch, state wasn't running?
2571 ShouldNotReachHere();
2572 return false;
2573 }
2574
2575 if (sr_notify(osthread) != 0) {
2576 ShouldNotReachHere();
2577 }
2578
2579 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
2580 while (true) {
2581 if (sr_semaphore.timedwait(2)) {
2582 break;
2583 } else {
2584 // timeout
2585 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
2586 if (cancelled == os::SuspendResume::SR_RUNNING) {
2587 return false;
2588 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
2589 // make sure that we consume the signal on the semaphore as well
2590 sr_semaphore.wait();
2591 break;
2592 } else {
2593 ShouldNotReachHere();
2594 return false;
2595 }
2596 }
2597 }
2598
2599 guarantee(osthread->sr.is_suspended(), "Must be suspended");
2600 return true;
2601 }
2602
2603 static void do_resume(OSThread* osthread) {
2604 assert(osthread->sr.is_suspended(), "thread should be suspended");
2605 assert(!sr_semaphore.trywait(), "invalid semaphore state");
2606
2607 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
2608 // failed to switch to WAKEUP_REQUEST
2609 ShouldNotReachHere();
2610 return;
2611 }
2612
2613 while (true) {
2614 if (sr_notify(osthread) == 0) {
2615 if (sr_semaphore.timedwait(2)) {
2616 if (osthread->sr.is_running()) {
2617 return;
2618 }
2619 }
2620 } else {
2621 ShouldNotReachHere();
2622 }
2623 }
2624
2625 guarantee(osthread->sr.is_running(), "Must be running!");
2626 }
2627
2628 ///////////////////////////////////////////////////////////////////////////////////
2629 // signal handling (except suspend/resume)
2630
2631 // This routine may be used by user applications as a "hook" to catch signals.
2632 // The user-defined signal handler must pass unrecognized signals to this
2633 // routine, and if it returns true (non-zero), then the signal handler must
2634 // return immediately. If the flag "abort_if_unrecognized" is true, then this
2635 // routine will never retun false (zero), but instead will execute a VM panic
2636 // routine kill the process.
2637 //
2638 // If this routine returns false, it is OK to call it again. This allows
2639 // the user-defined signal handler to perform checks either before or after
2640 // the VM performs its own checks. Naturally, the user code would be making
2641 // a serious error if it tried to handle an exception (such as a null check
2642 // or breakpoint) that the VM was generating for its own correct operation.
2643 //
2644 // This routine may recognize any of the following kinds of signals:
2645 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
2646 // It should be consulted by handlers for any of those signals.
2647 //
2648 // The caller of this routine must pass in the three arguments supplied
2649 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
2650 // field of the structure passed to sigaction(). This routine assumes that
2651 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
2652 //
2653 // Note that the VM will print warnings if it detects conflicting signal
2654 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
2655 //
2656 extern "C" JNIEXPORT int JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
2657 void* ucontext,
2658 int abort_if_unrecognized);
2659
2660 static void signalHandler(int sig, siginfo_t* info, void* uc) {
2661 assert(info != NULL && uc != NULL, "it must be old kernel");
2662 int orig_errno = errno; // Preserve errno value over signal handler.
2663 JVM_handle_bsd_signal(sig, info, uc, true);
2664 errno = orig_errno;
2665 }
2666
2667
2668 // This boolean allows users to forward their own non-matching signals
2669 // to JVM_handle_bsd_signal, harmlessly.
2670 bool os::Bsd::signal_handlers_are_installed = false;
2671
2672 // For signal-chaining
2673 bool os::Bsd::libjsig_is_loaded = false;
2674 typedef struct sigaction *(*get_signal_t)(int);
2675 get_signal_t os::Bsd::get_signal_action = NULL;
2676
2677 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
2678 struct sigaction *actp = NULL;
2679
2680 if (libjsig_is_loaded) {
2681 // Retrieve the old signal handler from libjsig
2682 actp = (*get_signal_action)(sig);
2683 }
2684 if (actp == NULL) {
2685 // Retrieve the preinstalled signal handler from jvm
2686 actp = os::Posix::get_preinstalled_handler(sig);
2687 }
2688
2689 return actp;
2690 }
2691
2692 static bool call_chained_handler(struct sigaction *actp, int sig,
2693 siginfo_t *siginfo, void *context) {
2694 // Call the old signal handler
2695 if (actp->sa_handler == SIG_DFL) {
2696 // It's more reasonable to let jvm treat it as an unexpected exception
2697 // instead of taking the default action.
2698 return false;
2699 } else if (actp->sa_handler != SIG_IGN) {
2700 if ((actp->sa_flags & SA_NODEFER) == 0) {
2701 // automaticlly block the signal
2702 sigaddset(&(actp->sa_mask), sig);
2703 }
2704
2705 sa_handler_t hand;
2706 sa_sigaction_t sa;
2707 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
2708 // retrieve the chained handler
2709 if (siginfo_flag_set) {
2710 sa = actp->sa_sigaction;
2711 } else {
2712 hand = actp->sa_handler;
2713 }
2714
2715 if ((actp->sa_flags & SA_RESETHAND) != 0) {
2716 actp->sa_handler = SIG_DFL;
2717 }
2718
2719 // try to honor the signal mask
2720 sigset_t oset;
2721 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
2722
2723 // call into the chained handler
2724 if (siginfo_flag_set) {
2725 (*sa)(sig, siginfo, context);
2726 } else {
2727 (*hand)(sig);
2728 }
2729
2730 // restore the signal mask
2731 pthread_sigmask(SIG_SETMASK, &oset, 0);
2732 }
2733 // Tell jvm's signal handler the signal is taken care of.
2734 return true;
2735 }
2736
2737 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
2738 bool chained = false;
2739 // signal-chaining
2740 if (UseSignalChaining) {
2741 struct sigaction *actp = get_chained_signal_action(sig);
2742 if (actp != NULL) {
2743 chained = call_chained_handler(actp, sig, siginfo, context);
2744 }
2745 }
2746 return chained;
2747 }
2748
2749 // for diagnostic
2750 int sigflags[NSIG];
2751
2752 int os::Bsd::get_our_sigflags(int sig) {
2753 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
2754 return sigflags[sig];
2755 }
2756
2757 void os::Bsd::set_our_sigflags(int sig, int flags) {
2758 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
2759 if (sig > 0 && sig < NSIG) {
2760 sigflags[sig] = flags;
2761 }
2762 }
2763
2764 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
2765 // Check for overwrite.
2766 struct sigaction oldAct;
2767 sigaction(sig, (struct sigaction*)NULL, &oldAct);
2768
2769 void* oldhand = oldAct.sa_sigaction
2770 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
2771 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
2772 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
2773 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
2774 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
2775 if (AllowUserSignalHandlers || !set_installed) {
2776 // Do not overwrite; user takes responsibility to forward to us.
2777 return;
2778 } else if (UseSignalChaining) {
2779 // save the old handler in jvm
2780 os::Posix::save_preinstalled_handler(sig, oldAct);
2781 // libjsig also interposes the sigaction() call below and saves the
2782 // old sigaction on it own.
2783 } else {
2784 fatal("Encountered unexpected pre-existing sigaction handler "
2785 "%#lx for signal %d.", (long)oldhand, sig);
2786 }
2787 }
2788
2789 struct sigaction sigAct;
2790 sigfillset(&(sigAct.sa_mask));
2791 sigAct.sa_handler = SIG_DFL;
2792 if (!set_installed) {
2793 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
2794 } else {
2795 sigAct.sa_sigaction = signalHandler;
2796 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
2797 }
2798 #ifdef __APPLE__
2799 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV
2800 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages"
2801 // if the signal handler declares it will handle it on alternate stack.
2802 // Notice we only declare we will handle it on alt stack, but we are not
2803 // actually going to use real alt stack - this is just a workaround.
2804 // Please see ux_exception.c, method catch_mach_exception_raise for details
2805 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c
2806 if (sig == SIGSEGV) {
2807 sigAct.sa_flags |= SA_ONSTACK;
2808 }
2809 #endif
2810
2811 // Save flags, which are set by ours
2812 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
2813 sigflags[sig] = sigAct.sa_flags;
2814
2815 int ret = sigaction(sig, &sigAct, &oldAct);
2816 assert(ret == 0, "check");
2817
2818 void* oldhand2 = oldAct.sa_sigaction
2819 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
2820 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
2821 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
2822 }
2823
2824 // install signal handlers for signals that HotSpot needs to
2825 // handle in order to support Java-level exception handling.
2826
2827 void os::Bsd::install_signal_handlers() {
2828 if (!signal_handlers_are_installed) {
2829 signal_handlers_are_installed = true;
2830
2831 // signal-chaining
2832 typedef void (*signal_setting_t)();
2833 signal_setting_t begin_signal_setting = NULL;
2834 signal_setting_t end_signal_setting = NULL;
2835 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
2836 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
2837 if (begin_signal_setting != NULL) {
2838 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
2839 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
2840 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
2841 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
2842 libjsig_is_loaded = true;
2843 assert(UseSignalChaining, "should enable signal-chaining");
2844 }
2845 if (libjsig_is_loaded) {
2846 // Tell libjsig jvm is setting signal handlers
2847 (*begin_signal_setting)();
2848 }
2849
2850 set_signal_handler(SIGSEGV, true);
2851 set_signal_handler(SIGPIPE, true);
2852 set_signal_handler(SIGBUS, true);
2853 set_signal_handler(SIGILL, true);
2854 set_signal_handler(SIGFPE, true);
2855 set_signal_handler(SIGXFSZ, true);
2856
2857 #if defined(__APPLE__)
2858 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
2859 // signals caught and handled by the JVM. To work around this, we reset the mach task
2860 // signal handler that's placed on our process by CrashReporter. This disables
2861 // CrashReporter-based reporting.
2862 //
2863 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
2864 // on caught fatal signals.
2865 //
2866 // Additionally, gdb installs both standard BSD signal handlers, and mach exception
2867 // handlers. By replacing the existing task exception handler, we disable gdb's mach
2868 // exception handling, while leaving the standard BSD signal handlers functional.
2869 kern_return_t kr;
2870 kr = task_set_exception_ports(mach_task_self(),
2871 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
2872 MACH_PORT_NULL,
2873 EXCEPTION_STATE_IDENTITY,
2874 MACHINE_THREAD_STATE);
2875
2876 assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
2877 #endif
2878
2879 if (libjsig_is_loaded) {
2880 // Tell libjsig jvm finishes setting signal handlers
2881 (*end_signal_setting)();
2882 }
2883
2884 // We don't activate signal checker if libjsig is in place, we trust ourselves
2885 // and if UserSignalHandler is installed all bets are off
2886 if (CheckJNICalls) {
2887 if (libjsig_is_loaded) {
2888 if (PrintJNIResolving) {
2889 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
2890 }
2891 check_signals = false;
2892 }
2893 if (AllowUserSignalHandlers) {
2894 if (PrintJNIResolving) {
2895 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
2896 }
2897 check_signals = false;
2898 }
2899 }
2900 }
2901 }
2902
2903
2904 /////
2905 // glibc on Bsd platform uses non-documented flag
2906 // to indicate, that some special sort of signal
2907 // trampoline is used.
2908 // We will never set this flag, and we should
2909 // ignore this flag in our diagnostic
2910 #ifdef SIGNIFICANT_SIGNAL_MASK
2911 #undef SIGNIFICANT_SIGNAL_MASK
2912 #endif
2913 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
2914
2915 static const char* get_signal_handler_name(address handler,
2916 char* buf, int buflen) {
2917 int offset;
2918 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
2919 if (found) {
2920 // skip directory names
2921 const char *p1, *p2;
2922 p1 = buf;
2923 size_t len = strlen(os::file_separator());
2924 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
2925 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
2926 } else {
2927 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
2928 }
2929 return buf;
2930 }
2931
2932 static void print_signal_handler(outputStream* st, int sig,
2933 char* buf, size_t buflen) {
2934 struct sigaction sa;
2935
2936 sigaction(sig, NULL, &sa);
2937
2938 // See comment for SIGNIFICANT_SIGNAL_MASK define
2939 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
2940
2941 st->print("%s: ", os::exception_name(sig, buf, buflen));
2942
2943 address handler = (sa.sa_flags & SA_SIGINFO)
2944 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
2945 : CAST_FROM_FN_PTR(address, sa.sa_handler);
2946
2947 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
2948 st->print("SIG_DFL");
2949 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
2950 st->print("SIG_IGN");
2951 } else {
2952 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
2953 }
2954
2955 st->print(", sa_mask[0]=");
2956 os::Posix::print_signal_set_short(st, &sa.sa_mask);
2957
2958 address rh = VMError::get_resetted_sighandler(sig);
2959 // May be, handler was resetted by VMError?
2960 if (rh != NULL) {
2961 handler = rh;
2962 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
2963 }
2964
2965 st->print(", sa_flags=");
2966 os::Posix::print_sa_flags(st, sa.sa_flags);
2967
2968 // Check: is it our handler?
2969 if (handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
2970 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
2971 // It is our signal handler
2972 // check for flags, reset system-used one!
2973 if ((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
2974 st->print(
2975 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
2976 os::Bsd::get_our_sigflags(sig));
2977 }
2978 }
2979 st->cr();
2980 }
2981
2982
2983 #define DO_SIGNAL_CHECK(sig) \
2984 do { \
2985 if (!sigismember(&check_signal_done, sig)) { \
2986 os::Bsd::check_signal_handler(sig); \
2987 } \
2988 } while (0)
2989
2990 // This method is a periodic task to check for misbehaving JNI applications
2991 // under CheckJNI, we can add any periodic checks here
2992
2993 void os::run_periodic_checks() {
2994
2995 if (check_signals == false) return;
2996
2997 // SEGV and BUS if overridden could potentially prevent
2998 // generation of hs*.log in the event of a crash, debugging
2999 // such a case can be very challenging, so we absolutely
3000 // check the following for a good measure:
3001 DO_SIGNAL_CHECK(SIGSEGV);
3002 DO_SIGNAL_CHECK(SIGILL);
3003 DO_SIGNAL_CHECK(SIGFPE);
3004 DO_SIGNAL_CHECK(SIGBUS);
3005 DO_SIGNAL_CHECK(SIGPIPE);
3006 DO_SIGNAL_CHECK(SIGXFSZ);
3007
3008
3009 // ReduceSignalUsage allows the user to override these handlers
3010 // see comments at the very top and jvm_md.h
3011 if (!ReduceSignalUsage) {
3012 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
3013 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
3014 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
3015 DO_SIGNAL_CHECK(BREAK_SIGNAL);
3016 }
3017
3018 DO_SIGNAL_CHECK(SR_signum);
3019 }
3020
3021 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
3022
3023 static os_sigaction_t os_sigaction = NULL;
3024
3025 void os::Bsd::check_signal_handler(int sig) {
3026 char buf[O_BUFLEN];
3027 address jvmHandler = NULL;
3028
3029
3030 struct sigaction act;
3031 if (os_sigaction == NULL) {
3032 // only trust the default sigaction, in case it has been interposed
3033 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
3034 if (os_sigaction == NULL) return;
3035 }
3036
3037 os_sigaction(sig, (struct sigaction*)NULL, &act);
3038
3039
3040 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3041
3042 address thisHandler = (act.sa_flags & SA_SIGINFO)
3043 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3044 : CAST_FROM_FN_PTR(address, act.sa_handler);
3045
3046
3047 switch (sig) {
3048 case SIGSEGV:
3049 case SIGBUS:
3050 case SIGFPE:
3051 case SIGPIPE:
3052 case SIGILL:
3053 case SIGXFSZ:
3054 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
3055 break;
3056
3057 case SHUTDOWN1_SIGNAL:
3058 case SHUTDOWN2_SIGNAL:
3059 case SHUTDOWN3_SIGNAL:
3060 case BREAK_SIGNAL:
3061 jvmHandler = (address)user_handler();
3062 break;
3063
3064 default:
3065 if (sig == SR_signum) {
3066 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3067 } else {
3068 return;
3069 }
3070 break;
3071 }
3072
3073 if (thisHandler != jvmHandler) {
3074 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3075 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3076 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3077 // No need to check this sig any longer
3078 sigaddset(&check_signal_done, sig);
3079 // Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN
3080 if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) {
3081 tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell",
3082 exception_name(sig, buf, O_BUFLEN));
3083 }
3084 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3085 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3086 tty->print("expected:");
3087 os::Posix::print_sa_flags(tty, os::Bsd::get_our_sigflags(sig));
3088 tty->cr();
3089 tty->print(" found:");
3090 os::Posix::print_sa_flags(tty, act.sa_flags);
3091 tty->cr();
3092 // No need to check this sig any longer
3093 sigaddset(&check_signal_done, sig);
3094 }
3095
3096 // Dump all the signal
3097 if (sigismember(&check_signal_done, sig)) {
3098 print_signal_handlers(tty, buf, O_BUFLEN);
3099 }
3100 }
3101
3102 extern void report_error(char* file_name, int line_no, char* title,
3103 char* format, ...);
3104
3105 // this is called _before_ the most of global arguments have been parsed
3106 void os::init(void) {
3107 char dummy; // used to get a guess on initial stack address
3108
3109 // With BsdThreads the JavaMain thread pid (primordial thread)
3110 // is different than the pid of the java launcher thread.
3111 // So, on Bsd, the launcher thread pid is passed to the VM
3112 // via the sun.java.launcher.pid property.
3113 // Use this property instead of getpid() if it was correctly passed.
3114 // See bug 6351349.
3115 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid();
3116
3117 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid();
3118
3119 clock_tics_per_sec = CLK_TCK;
3120
3121 init_random(1234567);
3122
3123 Bsd::set_page_size(getpagesize());
3124 if (Bsd::page_size() == -1) {
3125 fatal("os_bsd.cpp: os::init: sysconf failed (%s)", os::strerror(errno));
3126 }
3127 init_page_sizes((size_t) Bsd::page_size());
3128
3129 Bsd::initialize_system_info();
3130
3131 // _main_thread points to the thread that created/loaded the JVM.
3132 Bsd::_main_thread = pthread_self();
3133
3134 Bsd::clock_init();
3135 initial_time_count = javaTimeNanos();
3136
3137 os::Posix::init();
3138 }
3139
3140 // To install functions for atexit system call
3141 extern "C" {
3142 static void perfMemory_exit_helper() {
3143 perfMemory_exit();
3144 }
3145 }
3146
3147 // this is called _after_ the global arguments have been parsed
3148 jint os::init_2(void) {
3149
3150 // This could be set after os::Posix::init() but all platforms
3151 // have to set it the same so we have to mirror Solaris.
3152 DEBUG_ONLY(os::set_mutex_init_done();)
3153
3154 os::Posix::init_2();
3155
3156 // initialize suspend/resume support - must do this before signal_sets_init()
3157 if (SR_initialize() != 0) {
3158 perror("SR_initialize failed");
3159 return JNI_ERR;
3160 }
3161
3162 Bsd::signal_sets_init();
3163 Bsd::install_signal_handlers();
3164 // Initialize data for jdk.internal.misc.Signal
3165 if (!ReduceSignalUsage) {
3166 jdk_misc_signal_init();
3167 }
3168
3169 // Check and sets minimum stack sizes against command line options
3170 if (Posix::set_minimum_stack_sizes() == JNI_ERR) {
3171 return JNI_ERR;
3172 }
3173
3174 if (MaxFDLimit) {
3175 // set the number of file descriptors to max. print out error
3176 // if getrlimit/setrlimit fails but continue regardless.
3177 struct rlimit nbr_files;
3178 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3179 if (status != 0) {
3180 log_info(os)("os::init_2 getrlimit failed: %s", os::strerror(errno));
3181 } else {
3182 nbr_files.rlim_cur = nbr_files.rlim_max;
3183
3184 #ifdef __APPLE__
3185 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3186 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3187 // be used instead
3188 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3189 #endif
3190
3191 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3192 if (status != 0) {
3193 log_info(os)("os::init_2 setrlimit failed: %s", os::strerror(errno));
3194 }
3195 }
3196 }
3197
3198 // at-exit methods are called in the reverse order of their registration.
3199 // atexit functions are called on return from main or as a result of a
3200 // call to exit(3C). There can be only 32 of these functions registered
3201 // and atexit() does not set errno.
3202
3203 if (PerfAllowAtExitRegistration) {
3204 // only register atexit functions if PerfAllowAtExitRegistration is set.
3205 // atexit functions can be delayed until process exit time, which
3206 // can be problematic for embedded VM situations. Embedded VMs should
3207 // call DestroyJavaVM() to assure that VM resources are released.
3208
3209 // note: perfMemory_exit_helper atexit function may be removed in
3210 // the future if the appropriate cleanup code can be added to the
3211 // VM_Exit VMOperation's doit method.
3212 if (atexit(perfMemory_exit_helper) != 0) {
3213 warning("os::init_2 atexit(perfMemory_exit_helper) failed");
3214 }
3215 }
3216
3217 // initialize thread priority policy
3218 prio_init();
3219
3220 #ifdef __APPLE__
3221 // dynamically link to objective c gc registration
3222 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3223 if (handleLibObjc != NULL) {
3224 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3225 }
3226 #endif
3227
3228 return JNI_OK;
3229 }
3230
3231 // Mark the polling page as unreadable
3232 void os::make_polling_page_unreadable(void) {
3233 if (!guard_memory((char*)_polling_page, Bsd::page_size())) {
3234 fatal("Could not disable polling page");
3235 }
3236 }
3237
3238 // Mark the polling page as readable
3239 void os::make_polling_page_readable(void) {
3240 if (!bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
3241 fatal("Could not enable polling page");
3242 }
3243 }
3244
3245 int os::active_processor_count() {
3246 // User has overridden the number of active processors
3247 if (ActiveProcessorCount > 0) {
3248 log_trace(os)("active_processor_count: "
3249 "active processor count set by user : %d",
3250 ActiveProcessorCount);
3251 return ActiveProcessorCount;
3252 }
3253
3254 return _processor_count;
3255 }
3256
3257 void os::set_native_thread_name(const char *name) {
3258 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3259 // This is only supported in Snow Leopard and beyond
3260 if (name != NULL) {
3261 // Add a "Java: " prefix to the name
3262 char buf[MAXTHREADNAMESIZE];
3263 snprintf(buf, sizeof(buf), "Java: %s", name);
3264 pthread_setname_np(buf);
3265 }
3266 #endif
3267 }
3268
3269 bool os::distribute_processes(uint length, uint* distribution) {
3270 // Not yet implemented.
3271 return false;
3272 }
3273
3274 bool os::bind_to_processor(uint processor_id) {
3275 // Not yet implemented.
3276 return false;
3277 }
3278
3279 void os::SuspendedThreadTask::internal_do_task() {
3280 if (do_suspend(_thread->osthread())) {
3281 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
3282 do_task(context);
3283 do_resume(_thread->osthread());
3284 }
3285 }
3286
3287 ////////////////////////////////////////////////////////////////////////////////
3288 // debug support
3289
3290 bool os::find(address addr, outputStream* st) {
3291 Dl_info dlinfo;
3292 memset(&dlinfo, 0, sizeof(dlinfo));
3293 if (dladdr(addr, &dlinfo) != 0) {
3294 st->print(INTPTR_FORMAT ": ", (intptr_t)addr);
3295 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) {
3296 st->print("%s+%#x", dlinfo.dli_sname,
3297 (uint)((uintptr_t)addr - (uintptr_t)dlinfo.dli_saddr));
3298 } else if (dlinfo.dli_fbase != NULL) {
3299 st->print("<offset %#x>", (uint)((uintptr_t)addr - (uintptr_t)dlinfo.dli_fbase));
3300 } else {
3301 st->print("<absolute address>");
3302 }
3303 if (dlinfo.dli_fname != NULL) {
3304 st->print(" in %s", dlinfo.dli_fname);
3305 }
3306 if (dlinfo.dli_fbase != NULL) {
3307 st->print(" at " INTPTR_FORMAT, (intptr_t)dlinfo.dli_fbase);
3308 }
3309 st->cr();
3310
3311 if (Verbose) {
3312 // decode some bytes around the PC
3313 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
3314 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size());
3315 address lowest = (address) dlinfo.dli_sname;
3316 if (!lowest) lowest = (address) dlinfo.dli_fbase;
3317 if (begin < lowest) begin = lowest;
3318 Dl_info dlinfo2;
3319 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr
3320 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) {
3321 end = (address) dlinfo2.dli_saddr;
3322 }
3323 Disassembler::decode(begin, end, st);
3324 }
3325 return true;
3326 }
3327 return false;
3328 }
3329
3330 ////////////////////////////////////////////////////////////////////////////////
3331 // misc
3332
3333 // This does not do anything on Bsd. This is basically a hook for being
3334 // able to use structured exception handling (thread-local exception filters)
3335 // on, e.g., Win32.
3336 void os::os_exception_wrapper(java_call_t f, JavaValue* value,
3337 const methodHandle& method, JavaCallArguments* args,
3338 Thread* thread) {
3339 f(value, method, args, thread);
3340 }
3341
3342 void os::print_statistics() {
3343 }
3344
3345 bool os::message_box(const char* title, const char* message) {
3346 int i;
3347 fdStream err(defaultStream::error_fd());
3348 for (i = 0; i < 78; i++) err.print_raw("=");
3349 err.cr();
3350 err.print_raw_cr(title);
3351 for (i = 0; i < 78; i++) err.print_raw("-");
3352 err.cr();
3353 err.print_raw_cr(message);
3354 for (i = 0; i < 78; i++) err.print_raw("=");
3355 err.cr();
3356
3357 char buf[16];
3358 // Prevent process from exiting upon "read error" without consuming all CPU
3359 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3360
3361 return buf[0] == 'y' || buf[0] == 'Y';
3362 }
3363
3364 static inline struct timespec get_mtime(const char* filename) {
3365 struct stat st;
3366 int ret = os::stat(filename, &st);
3367 assert(ret == 0, "failed to stat() file '%s': %s", filename, os::strerror(errno));
3368 #ifdef __APPLE__
3369 return st.st_mtimespec;
3370 #else
3371 return st.st_mtim;
3372 #endif
3373 }
3374
3375 int os::compare_file_modified_times(const char* file1, const char* file2) {
3376 struct timespec filetime1 = get_mtime(file1);
3377 struct timespec filetime2 = get_mtime(file2);
3378 int diff = filetime1.tv_sec - filetime2.tv_sec;
3379 if (diff == 0) {
3380 return filetime1.tv_nsec - filetime2.tv_nsec;
3381 }
3382 return diff;
3383 }
3384
3385 // Is a (classpath) directory empty?
3386 bool os::dir_is_empty(const char* path) {
3387 DIR *dir = NULL;
3388 struct dirent *ptr;
3389
3390 dir = opendir(path);
3391 if (dir == NULL) return true;
3392
3393 // Scan the directory
3394 bool result = true;
3395 while (result && (ptr = readdir(dir)) != NULL) {
3396 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3397 result = false;
3398 }
3399 }
3400 closedir(dir);
3401 return result;
3402 }
3403
3404 // This code originates from JDK's sysOpen and open64_w
3405 // from src/solaris/hpi/src/system_md.c
3406
3407 int os::open(const char *path, int oflag, int mode) {
3408 if (strlen(path) > MAX_PATH - 1) {
3409 errno = ENAMETOOLONG;
3410 return -1;
3411 }
3412 int fd;
3413
3414 fd = ::open(path, oflag, mode);
3415 if (fd == -1) return -1;
3416
3417 // If the open succeeded, the file might still be a directory
3418 {
3419 struct stat buf;
3420 int ret = ::fstat(fd, &buf);
3421 int st_mode = buf.st_mode;
3422
3423 if (ret != -1) {
3424 if ((st_mode & S_IFMT) == S_IFDIR) {
3425 errno = EISDIR;
3426 ::close(fd);
3427 return -1;
3428 }
3429 } else {
3430 ::close(fd);
3431 return -1;
3432 }
3433 }
3434
3435 // All file descriptors that are opened in the JVM and not
3436 // specifically destined for a subprocess should have the
3437 // close-on-exec flag set. If we don't set it, then careless 3rd
3438 // party native code might fork and exec without closing all
3439 // appropriate file descriptors (e.g. as we do in closeDescriptors in
3440 // UNIXProcess.c), and this in turn might:
3441 //
3442 // - cause end-of-file to fail to be detected on some file
3443 // descriptors, resulting in mysterious hangs, or
3444 //
3445 // - might cause an fopen in the subprocess to fail on a system
3446 // suffering from bug 1085341.
3447 //
3448 // (Yes, the default setting of the close-on-exec flag is a Unix
3449 // design flaw)
3450 //
3451 // See:
3452 // 1085341: 32-bit stdio routines should support file descriptors >255
3453 // 4843136: (process) pipe file descriptor from Runtime.exec not being closed
3454 // 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
3455 //
3456 #ifdef FD_CLOEXEC
3457 {
3458 int flags = ::fcntl(fd, F_GETFD);
3459 if (flags != -1) {
3460 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
3461 }
3462 }
3463 #endif
3464
3465 return fd;
3466 }
3467
3468
3469 // create binary file, rewriting existing file if required
3470 int os::create_binary_file(const char* path, bool rewrite_existing) {
3471 int oflags = O_WRONLY | O_CREAT;
3472 if (!rewrite_existing) {
3473 oflags |= O_EXCL;
3474 }
3475 return ::open(path, oflags, S_IREAD | S_IWRITE);
3476 }
3477
3478 // return current position of file pointer
3479 jlong os::current_file_offset(int fd) {
3480 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
3481 }
3482
3483 // move file pointer to the specified offset
3484 jlong os::seek_to_file_offset(int fd, jlong offset) {
3485 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
3486 }
3487
3488 // This code originates from JDK's sysAvailable
3489 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
3490
3491 int os::available(int fd, jlong *bytes) {
3492 jlong cur, end;
3493 int mode;
3494 struct stat buf;
3495
3496 if (::fstat(fd, &buf) >= 0) {
3497 mode = buf.st_mode;
3498 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
3499 int n;
3500 if (::ioctl(fd, FIONREAD, &n) >= 0) {
3501 *bytes = n;
3502 return 1;
3503 }
3504 }
3505 }
3506 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
3507 return 0;
3508 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
3509 return 0;
3510 } else if (::lseek(fd, cur, SEEK_SET) == -1) {
3511 return 0;
3512 }
3513 *bytes = end - cur;
3514 return 1;
3515 }
3516
3517 // Map a block of memory.
3518 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
3519 char *addr, size_t bytes, bool read_only,
3520 bool allow_exec) {
3521 int prot;
3522 int flags;
3523
3524 if (read_only) {
3525 prot = PROT_READ;
3526 flags = MAP_SHARED;
3527 } else {
3528 prot = PROT_READ | PROT_WRITE;
3529 flags = MAP_PRIVATE;
3530 }
3531
3532 if (allow_exec) {
3533 prot |= PROT_EXEC;
3534 }
3535
3536 if (addr != NULL) {
3537 flags |= MAP_FIXED;
3538 }
3539
3540 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
3541 fd, file_offset);
3542 if (mapped_address == MAP_FAILED) {
3543 return NULL;
3544 }
3545 return mapped_address;
3546 }
3547
3548
3549 // Remap a block of memory.
3550 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
3551 char *addr, size_t bytes, bool read_only,
3552 bool allow_exec) {
3553 // same as map_memory() on this OS
3554 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
3555 allow_exec);
3556 }
3557
3558
3559 // Unmap a block of memory.
3560 bool os::pd_unmap_memory(char* addr, size_t bytes) {
3561 return munmap(addr, bytes) == 0;
3562 }
3563
3564 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
3565 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
3566 // of a thread.
3567 //
3568 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
3569 // the fast estimate available on the platform.
3570
3571 jlong os::current_thread_cpu_time() {
3572 #ifdef __APPLE__
3573 return os::thread_cpu_time(Thread::current(), true /* user + sys */);
3574 #else
3575 Unimplemented();
3576 return 0;
3577 #endif
3578 }
3579
3580 jlong os::thread_cpu_time(Thread* thread) {
3581 #ifdef __APPLE__
3582 return os::thread_cpu_time(thread, true /* user + sys */);
3583 #else
3584 Unimplemented();
3585 return 0;
3586 #endif
3587 }
3588
3589 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
3590 #ifdef __APPLE__
3591 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
3592 #else
3593 Unimplemented();
3594 return 0;
3595 #endif
3596 }
3597
3598 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
3599 #ifdef __APPLE__
3600 struct thread_basic_info tinfo;
3601 mach_msg_type_number_t tcount = THREAD_INFO_MAX;
3602 kern_return_t kr;
3603 thread_t mach_thread;
3604
3605 mach_thread = thread->osthread()->thread_id();
3606 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
3607 if (kr != KERN_SUCCESS) {
3608 return -1;
3609 }
3610
3611 if (user_sys_cpu_time) {
3612 jlong nanos;
3613 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
3614 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
3615 return nanos;
3616 } else {
3617 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
3618 }
3619 #else
3620 Unimplemented();
3621 return 0;
3622 #endif
3623 }
3624
3625
3626 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
3627 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
3628 info_ptr->may_skip_backward = false; // elapsed time not wall time
3629 info_ptr->may_skip_forward = false; // elapsed time not wall time
3630 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
3631 }
3632
3633 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
3634 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
3635 info_ptr->may_skip_backward = false; // elapsed time not wall time
3636 info_ptr->may_skip_forward = false; // elapsed time not wall time
3637 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
3638 }
3639
3640 bool os::is_thread_cpu_time_supported() {
3641 #ifdef __APPLE__
3642 return true;
3643 #else
3644 return false;
3645 #endif
3646 }
3647
3648 // System loadavg support. Returns -1 if load average cannot be obtained.
3649 // Bsd doesn't yet have a (official) notion of processor sets,
3650 // so just return the system wide load average.
3651 int os::loadavg(double loadavg[], int nelem) {
3652 return ::getloadavg(loadavg, nelem);
3653 }
3654
3655 void os::pause() {
3656 char filename[MAX_PATH];
3657 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
3658 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
3659 } else {
3660 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
3661 }
3662
3663 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
3664 if (fd != -1) {
3665 struct stat buf;
3666 ::close(fd);
3667 while (::stat(filename, &buf) == 0) {
3668 (void)::poll(NULL, 0, 100);
3669 }
3670 } else {
3671 jio_fprintf(stderr,
3672 "Could not open pause file '%s', continuing immediately.\n", filename);
3673 }
3674 }
3675
3676 // Darwin has no "environ" in a dynamic library.
3677 #ifdef __APPLE__
3678 #include <crt_externs.h>
3679 #define environ (*_NSGetEnviron())
3680 #else
3681 extern char** environ;
3682 #endif
3683
3684 // Run the specified command in a separate process. Return its exit value,
3685 // or -1 on failure (e.g. can't fork a new process).
3686 // Unlike system(), this function can be called from signal handler. It
3687 // doesn't block SIGINT et al.
3688 int os::fork_and_exec(char* cmd, bool use_vfork_if_available) {
3689 const char * argv[4] = {"sh", "-c", cmd, NULL};
3690
3691 // fork() in BsdThreads/NPTL is not async-safe. It needs to run
3692 // pthread_atfork handlers and reset pthread library. All we need is a
3693 // separate process to execve. Make a direct syscall to fork process.
3694 // On IA64 there's no fork syscall, we have to use fork() and hope for
3695 // the best...
3696 pid_t pid = fork();
3697
3698 if (pid < 0) {
3699 // fork failed
3700 return -1;
3701
3702 } else if (pid == 0) {
3703 // child process
3704
3705 // execve() in BsdThreads will call pthread_kill_other_threads_np()
3706 // first to kill every thread on the thread list. Because this list is
3707 // not reset by fork() (see notes above), execve() will instead kill
3708 // every thread in the parent process. We know this is the only thread
3709 // in the new process, so make a system call directly.
3710 // IA64 should use normal execve() from glibc to match the glibc fork()
3711 // above.
3712 execve("/bin/sh", (char* const*)argv, environ);
3713
3714 // execve failed
3715 _exit(-1);
3716
3717 } else {
3718 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
3719 // care about the actual exit code, for now.
3720
3721 int status;
3722
3723 // Wait for the child process to exit. This returns immediately if
3724 // the child has already exited. */
3725 while (waitpid(pid, &status, 0) < 0) {
3726 switch (errno) {
3727 case ECHILD: return 0;
3728 case EINTR: break;
3729 default: return -1;
3730 }
3731 }
3732
3733 if (WIFEXITED(status)) {
3734 // The child exited normally; get its exit code.
3735 return WEXITSTATUS(status);
3736 } else if (WIFSIGNALED(status)) {
3737 // The child exited because of a signal
3738 // The best value to return is 0x80 + signal number,
3739 // because that is what all Unix shells do, and because
3740 // it allows callers to distinguish between process exit and
3741 // process death by signal.
3742 return 0x80 + WTERMSIG(status);
3743 } else {
3744 // Unknown exit code; pass it through
3745 return status;
3746 }
3747 }
3748 }
3749
3750 // Get the default path to the core file
3751 // Returns the length of the string
3752 int os::get_core_path(char* buffer, size_t bufferSize) {
3753 int n = jio_snprintf(buffer, bufferSize, "/cores/core.%d", 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 #ifndef PRODUCT
3762 void TestReserveMemorySpecial_test() {
3763 // No tests available for this platform
3764 }
3765 #endif
3766
3767 bool os::start_debugging(char *buf, int buflen) {
3768 int len = (int)strlen(buf);
3769 char *p = &buf[len];
3770
3771 jio_snprintf(p, buflen-len,
3772 "\n\n"
3773 "Do you want to debug the problem?\n\n"
3774 "To debug, run 'gdb /proc/%d/exe %d'; then switch to thread " INTX_FORMAT " (" INTPTR_FORMAT ")\n"
3775 "Enter 'yes' to launch gdb automatically (PATH must include gdb)\n"
3776 "Otherwise, press RETURN to abort...",
3777 os::current_process_id(), os::current_process_id(),
3778 os::current_thread_id(), os::current_thread_id());
3779
3780 bool yes = os::message_box("Unexpected Error", buf);
3781
3782 if (yes) {
3783 // yes, user asked VM to launch debugger
3784 jio_snprintf(buf, sizeof(buf), "gdb /proc/%d/exe %d",
3785 os::current_process_id(), os::current_process_id());
3786
3787 os::fork_and_exec(buf);
3788 yes = false;
3789 }
3790 return yes;
3791 }