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 "logging/logStream.hpp"
37 #include "memory/allocation.inline.hpp"
38 #include "memory/filemap.hpp"
39 #include "oops/oop.inline.hpp"
40 #include "os_bsd.inline.hpp"
41 #include "os_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 <sys/types.h>
75 # include <sys/mman.h>
76 # include <sys/stat.h>
77 # include <sys/select.h>
78 # include <pthread.h>
79 # include <signal.h>
80 # include <errno.h>
81 # include <dlfcn.h>
82 # include <stdio.h>
83 # include <unistd.h>
84 # include <sys/resource.h>
85 # include <pthread.h>
86 # include <sys/stat.h>
87 # include <sys/time.h>
88 # include <sys/times.h>
89 # include <sys/utsname.h>
90 # include <sys/socket.h>
91 # include <sys/wait.h>
92 # include <time.h>
93 # include <pwd.h>
94 # include <poll.h>
95 # include <fcntl.h>
96 # include <string.h>
97 # include <sys/param.h>
98 # include <sys/sysctl.h>
99 # include <sys/ipc.h>
100 # include <sys/shm.h>
101 #ifndef __APPLE__
102 # include <link.h>
103 #endif
104 # include <stdint.h>
105 # include <inttypes.h>
106 # include <sys/ioctl.h>
107 # include <sys/syscall.h>
108
109 #if defined(__FreeBSD__) || defined(__NetBSD__)
110 #include <elf.h>
111 #endif
112
113 #ifdef __APPLE__
114 #include <mach/mach.h> // semaphore_* API
115 #include <mach-o/dyld.h>
116 #include <sys/proc_info.h>
117 #include <objc/objc-auto.h>
118 #endif
119
120 #ifndef MAP_ANONYMOUS
121 #define MAP_ANONYMOUS MAP_ANON
122 #endif
123
124 #define MAX_PATH (2 * K)
125
126 // for timer info max values which include all bits
127 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF)
128
129 #define LARGEPAGES_BIT (1 << 6)
130
131 ////////////////////////////////////////////////////////////////////////////////
132 // global variables
133 julong os::Bsd::_physical_memory = 0;
134
135 #ifdef __APPLE__
136 mach_timebase_info_data_t os::Bsd::_timebase_info = {0, 0};
137 volatile uint64_t os::Bsd::_max_abstime = 0;
138 #else
139 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL;
140 #endif
141 pthread_t os::Bsd::_main_thread;
142 int os::Bsd::_page_size = -1;
143
144 static jlong initial_time_count=0;
145
146 static int clock_tics_per_sec = 100;
147
148 // For diagnostics to print a message once. see run_periodic_checks
149 static sigset_t check_signal_done;
150 static bool check_signals = true;
151
152 static pid_t _initial_pid = 0;
153
154 // Signal number used to suspend/resume a thread
155
156 // do not use any signal number less than SIGSEGV, see 4355769
157 static int SR_signum = SIGUSR2;
158 sigset_t SR_sigset;
159
160
161 ////////////////////////////////////////////////////////////////////////////////
162 // utility functions
163
164 static int SR_initialize();
165
166 julong os::available_memory() {
167 return Bsd::available_memory();
168 }
169
170 // available here means free
171 julong os::Bsd::available_memory() {
172 uint64_t available = physical_memory() >> 2;
173 #ifdef __APPLE__
174 mach_msg_type_number_t count = HOST_VM_INFO64_COUNT;
175 vm_statistics64_data_t vmstat;
176 kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64,
177 (host_info64_t)&vmstat, &count);
178 assert(kerr == KERN_SUCCESS,
179 "host_statistics64 failed - check mach_host_self() and count");
180 if (kerr == KERN_SUCCESS) {
181 available = vmstat.free_count * os::vm_page_size();
182 }
183 #endif
184 return available;
185 }
186
187 julong os::physical_memory() {
188 return Bsd::physical_memory();
189 }
190
191 // Return true if user is running as root.
192
193 bool os::have_special_privileges() {
194 static bool init = false;
195 static bool privileges = false;
196 if (!init) {
197 privileges = (getuid() != geteuid()) || (getgid() != getegid());
198 init = true;
199 }
200 return privileges;
201 }
202
203
204
205 // Cpu architecture string
206 #if defined(ZERO)
207 static char cpu_arch[] = ZERO_LIBARCH;
208 #elif defined(IA64)
209 static char cpu_arch[] = "ia64";
210 #elif defined(IA32)
211 static char cpu_arch[] = "i386";
212 #elif defined(AMD64)
213 static char cpu_arch[] = "amd64";
214 #elif defined(ARM)
215 static char cpu_arch[] = "arm";
216 #elif defined(PPC32)
217 static char cpu_arch[] = "ppc";
218 #elif defined(SPARC)
219 #ifdef _LP64
220 static char cpu_arch[] = "sparcv9";
221 #else
222 static char cpu_arch[] = "sparc";
223 #endif
224 #else
225 #error Add appropriate cpu_arch setting
226 #endif
227
228 // Compiler variant
229 #ifdef COMPILER2
230 #define COMPILER_VARIANT "server"
231 #else
232 #define COMPILER_VARIANT "client"
233 #endif
234
235
236 void os::Bsd::initialize_system_info() {
237 int mib[2];
238 size_t len;
239 int cpu_val;
240 julong mem_val;
241
242 // get processors count via hw.ncpus sysctl
243 mib[0] = CTL_HW;
244 mib[1] = HW_NCPU;
245 len = sizeof(cpu_val);
246 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) {
247 assert(len == sizeof(cpu_val), "unexpected data size");
248 set_processor_count(cpu_val);
249 } else {
250 set_processor_count(1); // fallback
251 }
252
253 // get physical memory via hw.memsize sysctl (hw.memsize is used
254 // since it returns a 64 bit value)
255 mib[0] = CTL_HW;
256
257 #if defined (HW_MEMSIZE) // Apple
258 mib[1] = HW_MEMSIZE;
259 #elif defined(HW_PHYSMEM) // Most of BSD
260 mib[1] = HW_PHYSMEM;
261 #elif defined(HW_REALMEM) // Old FreeBSD
262 mib[1] = HW_REALMEM;
263 #else
264 #error No ways to get physmem
265 #endif
266
267 len = sizeof(mem_val);
268 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) {
269 assert(len == sizeof(mem_val), "unexpected data size");
270 _physical_memory = mem_val;
271 } else {
272 _physical_memory = 256 * 1024 * 1024; // fallback (XXXBSD?)
273 }
274
275 #ifdef __OpenBSD__
276 {
277 // limit _physical_memory memory view on OpenBSD since
278 // datasize rlimit restricts us anyway.
279 struct rlimit limits;
280 getrlimit(RLIMIT_DATA, &limits);
281 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur);
282 }
283 #endif
284 }
285
286 #ifdef __APPLE__
287 static const char *get_home() {
288 const char *home_dir = ::getenv("HOME");
289 if ((home_dir == NULL) || (*home_dir == '\0')) {
290 struct passwd *passwd_info = getpwuid(geteuid());
291 if (passwd_info != NULL) {
292 home_dir = passwd_info->pw_dir;
293 }
294 }
295
296 return home_dir;
297 }
298 #endif
299
300 void os::init_system_properties_values() {
301 // The next steps are taken in the product version:
302 //
303 // Obtain the JAVA_HOME value from the location of libjvm.so.
304 // This library should be located at:
305 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so.
306 //
307 // If "/jre/lib/" appears at the right place in the path, then we
308 // assume libjvm.so is installed in a JDK and we use this path.
309 //
310 // Otherwise exit with message: "Could not create the Java virtual machine."
311 //
312 // The following extra steps are taken in the debugging version:
313 //
314 // If "/jre/lib/" does NOT appear at the right place in the path
315 // instead of exit check for $JAVA_HOME environment variable.
316 //
317 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>,
318 // then we append a fake suffix "hotspot/libjvm.so" to this path so
319 // it looks like libjvm.so is installed there
320 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so.
321 //
322 // Otherwise exit.
323 //
324 // Important note: if the location of libjvm.so changes this
325 // code needs to be changed accordingly.
326
327 // See ld(1):
328 // The linker uses the following search paths to locate required
329 // shared libraries:
330 // 1: ...
331 // ...
332 // 7: The default directories, normally /lib and /usr/lib.
333 #ifndef DEFAULT_LIBPATH
334 #define DEFAULT_LIBPATH "/lib:/usr/lib"
335 #endif
336
337 // Base path of extensions installed on the system.
338 #define SYS_EXT_DIR "/usr/java/packages"
339 #define EXTENSIONS_DIR "/lib/ext"
340
341 #ifndef __APPLE__
342
343 // Buffer that fits several sprintfs.
344 // Note that the space for the colon and the trailing null are provided
345 // by the nulls included by the sizeof operator.
346 const size_t bufsize =
347 MAX2((size_t)MAXPATHLEN, // For dll_dir & friends.
348 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + sizeof(SYS_EXT_DIR) + sizeof(EXTENSIONS_DIR)); // extensions dir
349 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
350
351 // sysclasspath, java_home, dll_dir
352 {
353 char *pslash;
354 os::jvm_path(buf, bufsize);
355
356 // Found the full path to libjvm.so.
357 // Now cut the path to <java_home>/jre if we can.
358 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
359 pslash = strrchr(buf, '/');
360 if (pslash != NULL) {
361 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
362 }
363 Arguments::set_dll_dir(buf);
364
365 if (pslash != NULL) {
366 pslash = strrchr(buf, '/');
367 if (pslash != NULL) {
368 *pslash = '\0'; // Get rid of /<arch>.
369 pslash = strrchr(buf, '/');
370 if (pslash != NULL) {
371 *pslash = '\0'; // Get rid of /lib.
372 }
373 }
374 }
375 Arguments::set_java_home(buf);
376 set_boot_path('/', ':');
377 }
378
379 // Where to look for native libraries.
380 //
381 // Note: Due to a legacy implementation, most of the library path
382 // is set in the launcher. This was to accomodate linking restrictions
383 // on legacy Bsd implementations (which are no longer supported).
384 // Eventually, all the library path setting will be done here.
385 //
386 // However, to prevent the proliferation of improperly built native
387 // libraries, the new path component /usr/java/packages is added here.
388 // Eventually, all the library path setting will be done here.
389 {
390 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
391 // should always exist (until the legacy problem cited above is
392 // addressed).
393 const char *v = ::getenv("LD_LIBRARY_PATH");
394 const char *v_colon = ":";
395 if (v == NULL) { v = ""; v_colon = ""; }
396 // That's +1 for the colon and +1 for the trailing '\0'.
397 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char,
398 strlen(v) + 1 +
399 sizeof(SYS_EXT_DIR) + sizeof("/lib/") + strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH) + 1,
400 mtInternal);
401 sprintf(ld_library_path, "%s%s" SYS_EXT_DIR "/lib/%s:" DEFAULT_LIBPATH, v, v_colon, cpu_arch);
402 Arguments::set_library_path(ld_library_path);
403 FREE_C_HEAP_ARRAY(char, ld_library_path);
404 }
405
406 // Extensions directories.
407 sprintf(buf, "%s" EXTENSIONS_DIR ":" SYS_EXT_DIR EXTENSIONS_DIR, Arguments::get_java_home());
408 Arguments::set_ext_dirs(buf);
409
410 FREE_C_HEAP_ARRAY(char, buf);
411
412 #else // __APPLE__
413
414 #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions"
415 #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java"
416
417 const char *user_home_dir = get_home();
418 // The null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir.
419 size_t system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) +
420 sizeof(SYS_EXTENSIONS_DIRS);
421
422 // Buffer that fits several sprintfs.
423 // Note that the space for the colon and the trailing null are provided
424 // by the nulls included by the sizeof operator.
425 const size_t bufsize =
426 MAX2((size_t)MAXPATHLEN, // for dll_dir & friends.
427 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + system_ext_size); // extensions dir
428 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
429
430 // sysclasspath, java_home, dll_dir
431 {
432 char *pslash;
433 os::jvm_path(buf, bufsize);
434
435 // Found the full path to libjvm.so.
436 // Now cut the path to <java_home>/jre if we can.
437 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
438 pslash = strrchr(buf, '/');
439 if (pslash != NULL) {
440 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
441 }
442 #ifdef STATIC_BUILD
443 strcat(buf, "/lib");
444 #endif
445
446 Arguments::set_dll_dir(buf);
447
448 if (pslash != NULL) {
449 pslash = strrchr(buf, '/');
450 if (pslash != NULL) {
451 *pslash = '\0'; // Get rid of /lib.
452 }
453 }
454 Arguments::set_java_home(buf);
455 set_boot_path('/', ':');
456 }
457
458 // Where to look for native libraries.
459 //
460 // Note: Due to a legacy implementation, most of the library path
461 // is set in the launcher. This was to accomodate linking restrictions
462 // on legacy Bsd implementations (which are no longer supported).
463 // Eventually, all the library path setting will be done here.
464 //
465 // However, to prevent the proliferation of improperly built native
466 // libraries, the new path component /usr/java/packages is added here.
467 // Eventually, all the library path setting will be done here.
468 {
469 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
470 // should always exist (until the legacy problem cited above is
471 // addressed).
472 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code
473 // can specify a directory inside an app wrapper
474 const char *l = ::getenv("JAVA_LIBRARY_PATH");
475 const char *l_colon = ":";
476 if (l == NULL) { l = ""; l_colon = ""; }
477
478 const char *v = ::getenv("DYLD_LIBRARY_PATH");
479 const char *v_colon = ":";
480 if (v == NULL) { v = ""; v_colon = ""; }
481
482 // Apple's Java6 has "." at the beginning of java.library.path.
483 // OpenJDK on Windows has "." at the end of java.library.path.
484 // OpenJDK on Linux and Solaris don't have "." in java.library.path
485 // at all. To ease the transition from Apple's Java6 to OpenJDK7,
486 // "." is appended to the end of java.library.path. Yes, this
487 // could cause a change in behavior, but Apple's Java6 behavior
488 // can be achieved by putting "." at the beginning of the
489 // JAVA_LIBRARY_PATH environment variable.
490 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char,
491 strlen(v) + 1 + strlen(l) + 1 +
492 system_ext_size + 3,
493 mtInternal);
494 sprintf(ld_library_path, "%s%s%s%s%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS ":.",
495 v, v_colon, l, l_colon, user_home_dir);
496 Arguments::set_library_path(ld_library_path);
497 FREE_C_HEAP_ARRAY(char, ld_library_path);
498 }
499
500 // Extensions directories.
501 //
502 // Note that the space for the colon and the trailing null are provided
503 // by the nulls included by the sizeof operator (so actually one byte more
504 // than necessary is allocated).
505 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS,
506 user_home_dir, Arguments::get_java_home());
507 Arguments::set_ext_dirs(buf);
508
509 FREE_C_HEAP_ARRAY(char, buf);
510
511 #undef SYS_EXTENSIONS_DIR
512 #undef SYS_EXTENSIONS_DIRS
513
514 #endif // __APPLE__
515
516 #undef SYS_EXT_DIR
517 #undef EXTENSIONS_DIR
518 }
519
520 ////////////////////////////////////////////////////////////////////////////////
521 // breakpoint support
522
523 void os::breakpoint() {
524 BREAKPOINT;
525 }
526
527 extern "C" void breakpoint() {
528 // use debugger to set breakpoint here
529 }
530
531 ////////////////////////////////////////////////////////////////////////////////
532 // signal support
533
534 debug_only(static bool signal_sets_initialized = false);
535 static sigset_t unblocked_sigs, vm_sigs;
536
537 void os::Bsd::signal_sets_init() {
538 // Should also have an assertion stating we are still single-threaded.
539 assert(!signal_sets_initialized, "Already initialized");
540 // Fill in signals that are necessarily unblocked for all threads in
541 // the VM. Currently, we unblock the following signals:
542 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
543 // by -Xrs (=ReduceSignalUsage));
544 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
545 // other threads. The "ReduceSignalUsage" boolean tells us not to alter
546 // the dispositions or masks wrt these signals.
547 // Programs embedding the VM that want to use the above signals for their
548 // own purposes must, at this time, use the "-Xrs" option to prevent
549 // interference with shutdown hooks and BREAK_SIGNAL thread dumping.
550 // (See bug 4345157, and other related bugs).
551 // In reality, though, unblocking these signals is really a nop, since
552 // these signals are not blocked by default.
553 sigemptyset(&unblocked_sigs);
554 sigaddset(&unblocked_sigs, SIGILL);
555 sigaddset(&unblocked_sigs, SIGSEGV);
556 sigaddset(&unblocked_sigs, SIGBUS);
557 sigaddset(&unblocked_sigs, SIGFPE);
558 sigaddset(&unblocked_sigs, SR_signum);
559
560 if (!ReduceSignalUsage) {
561 if (!os::Posix::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
562 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
563
564 }
565 if (!os::Posix::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
566 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
567 }
568 if (!os::Posix::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
569 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
570 }
571 }
572 // Fill in signals that are blocked by all but the VM thread.
573 sigemptyset(&vm_sigs);
574 if (!ReduceSignalUsage) {
575 sigaddset(&vm_sigs, BREAK_SIGNAL);
576 }
577 debug_only(signal_sets_initialized = true);
578
579 }
580
581 // These are signals that are unblocked while a thread is running Java.
582 // (For some reason, they get blocked by default.)
583 sigset_t* os::Bsd::unblocked_signals() {
584 assert(signal_sets_initialized, "Not initialized");
585 return &unblocked_sigs;
586 }
587
588 // These are the signals that are blocked while a (non-VM) thread is
589 // running Java. Only the VM thread handles these signals.
590 sigset_t* os::Bsd::vm_signals() {
591 assert(signal_sets_initialized, "Not initialized");
592 return &vm_sigs;
593 }
594
595 void os::Bsd::hotspot_sigmask(Thread* thread) {
596
597 //Save caller's signal mask before setting VM signal mask
598 sigset_t caller_sigmask;
599 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
600
601 OSThread* osthread = thread->osthread();
602 osthread->set_caller_sigmask(caller_sigmask);
603
604 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL);
605
606 if (!ReduceSignalUsage) {
607 if (thread->is_VM_thread()) {
608 // Only the VM thread handles BREAK_SIGNAL ...
609 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
610 } else {
611 // ... all other threads block BREAK_SIGNAL
612 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
613 }
614 }
615 }
616
617
618 //////////////////////////////////////////////////////////////////////////////
619 // create new thread
620
621 #ifdef __APPLE__
622 // library handle for calling objc_registerThreadWithCollector()
623 // without static linking to the libobjc library
624 #define OBJC_LIB "/usr/lib/libobjc.dylib"
625 #define OBJC_GCREGISTER "objc_registerThreadWithCollector"
626 typedef void (*objc_registerThreadWithCollector_t)();
627 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction;
628 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL;
629 #endif
630
631 #ifdef __APPLE__
632 static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) {
633 // Additional thread_id used to correlate threads in SA
634 thread_identifier_info_data_t m_ident_info;
635 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT;
636
637 thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO,
638 (thread_info_t) &m_ident_info, &count);
639
640 return m_ident_info.thread_id;
641 }
642 #endif
643
644 // Thread start routine for all newly created threads
645 static void *thread_native_entry(Thread *thread) {
646
647 thread->record_stack_base_and_size();
648
649 // Try to randomize the cache line index of hot stack frames.
650 // This helps when threads of the same stack traces evict each other's
651 // cache lines. The threads can be either from the same JVM instance, or
652 // from different JVM instances. The benefit is especially true for
653 // processors with hyperthreading technology.
654 static int counter = 0;
655 int pid = os::current_process_id();
656 alloca(((pid ^ counter++) & 7) * 128);
657
658 thread->initialize_thread_current();
659
660 OSThread* osthread = thread->osthread();
661 Monitor* sync = osthread->startThread_lock();
662
663 osthread->set_thread_id(os::Bsd::gettid());
664
665 log_info(os, thread)("Thread is alive (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").",
666 os::current_thread_id(), (uintx) pthread_self());
667
668 #ifdef __APPLE__
669 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
670 guarantee(unique_thread_id != 0, "unique thread id was not found");
671 osthread->set_unique_thread_id(unique_thread_id);
672 #endif
673 // initialize signal mask for this thread
674 os::Bsd::hotspot_sigmask(thread);
675
676 // initialize floating point control register
677 os::Bsd::init_thread_fpu_state();
678
679 #ifdef __APPLE__
680 // register thread with objc gc
681 if (objc_registerThreadWithCollectorFunction != NULL) {
682 objc_registerThreadWithCollectorFunction();
683 }
684 #endif
685
686 // handshaking with parent thread
687 {
688 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
689
690 // notify parent thread
691 osthread->set_state(INITIALIZED);
692 sync->notify_all();
693
694 // wait until os::start_thread()
695 while (osthread->get_state() == INITIALIZED) {
696 sync->wait(Mutex::_no_safepoint_check_flag);
697 }
698 }
699
700 // call one more level start routine
701 thread->call_run();
702
703 // Note: at this point the thread object may already have deleted itself.
704 // Prevent dereferencing it from here on out.
705 thread = NULL;
706
707 log_info(os, thread)("Thread finished (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").",
708 os::current_thread_id(), (uintx) pthread_self());
709
710 return 0;
711 }
712
713 bool os::create_thread(Thread* thread, ThreadType thr_type,
714 size_t req_stack_size) {
715 assert(thread->osthread() == NULL, "caller responsible");
716
717 // Allocate the OSThread object
718 OSThread* osthread = new OSThread(NULL, NULL);
719 if (osthread == NULL) {
720 return false;
721 }
722
723 // set the correct thread state
724 osthread->set_thread_type(thr_type);
725
726 // Initial state is ALLOCATED but not INITIALIZED
727 osthread->set_state(ALLOCATED);
728
729 thread->set_osthread(osthread);
730
731 // init thread attributes
732 pthread_attr_t attr;
733 pthread_attr_init(&attr);
734 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
735
736 // calculate stack size if it's not specified by caller
737 size_t stack_size = os::Posix::get_initial_stack_size(thr_type, req_stack_size);
738 int status = pthread_attr_setstacksize(&attr, stack_size);
739 assert_status(status == 0, status, "pthread_attr_setstacksize");
740
741 ThreadState state;
742
743 {
744 pthread_t tid;
745 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) thread_native_entry, thread);
746
747 char buf[64];
748 if (ret == 0) {
749 log_info(os, thread)("Thread started (pthread id: " UINTX_FORMAT ", attributes: %s). ",
750 (uintx) tid, os::Posix::describe_pthread_attr(buf, sizeof(buf), &attr));
751 } else {
752 log_warning(os, thread)("Failed to start thread - pthread_create failed (%s) for attributes: %s.",
753 os::errno_name(ret), os::Posix::describe_pthread_attr(buf, sizeof(buf), &attr));
754 // Log some OS information which might explain why creating the thread failed.
755 log_info(os, thread)("Number of threads approx. running in the VM: %d", Threads::number_of_threads());
756 LogStream st(Log(os, thread)::info());
757 os::Posix::print_rlimit_info(&st);
758 os::print_memory_info(&st);
759 }
760
761 pthread_attr_destroy(&attr);
762
763 if (ret != 0) {
764 // Need to clean up stuff we've allocated so far
765 thread->set_osthread(NULL);
766 delete osthread;
767 return false;
768 }
769
770 // Store pthread info into the OSThread
771 osthread->set_pthread_id(tid);
772
773 // Wait until child thread is either initialized or aborted
774 {
775 Monitor* sync_with_child = osthread->startThread_lock();
776 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
777 while ((state = osthread->get_state()) == ALLOCATED) {
778 sync_with_child->wait(Mutex::_no_safepoint_check_flag);
779 }
780 }
781
782 }
783
784 // Aborted due to thread limit being reached
785 if (state == ZOMBIE) {
786 thread->set_osthread(NULL);
787 delete osthread;
788 return false;
789 }
790
791 // The thread is returned suspended (in state INITIALIZED),
792 // and is started higher up in the call chain
793 assert(state == INITIALIZED, "race condition");
794 return true;
795 }
796
797 /////////////////////////////////////////////////////////////////////////////
798 // attach existing thread
799
800 // bootstrap the main thread
801 bool os::create_main_thread(JavaThread* thread) {
802 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
803 return create_attached_thread(thread);
804 }
805
806 bool os::create_attached_thread(JavaThread* thread) {
807 #ifdef ASSERT
808 thread->verify_not_published();
809 #endif
810
811 // Allocate the OSThread object
812 OSThread* osthread = new OSThread(NULL, NULL);
813
814 if (osthread == NULL) {
815 return false;
816 }
817
818 osthread->set_thread_id(os::Bsd::gettid());
819
820 // Store pthread info into the OSThread
821 #ifdef __APPLE__
822 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
823 guarantee(unique_thread_id != 0, "just checking");
824 osthread->set_unique_thread_id(unique_thread_id);
825 #endif
826 osthread->set_pthread_id(::pthread_self());
827
828 // initialize floating point control register
829 os::Bsd::init_thread_fpu_state();
830
831 // Initial thread state is RUNNABLE
832 osthread->set_state(RUNNABLE);
833
834 thread->set_osthread(osthread);
835
836 // initialize signal mask for this thread
837 // and save the caller's signal mask
838 os::Bsd::hotspot_sigmask(thread);
839
840 log_info(os, thread)("Thread attached (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").",
841 os::current_thread_id(), (uintx) pthread_self());
842
843 return true;
844 }
845
846 void os::pd_start_thread(Thread* thread) {
847 OSThread * osthread = thread->osthread();
848 assert(osthread->get_state() != INITIALIZED, "just checking");
849 Monitor* sync_with_child = osthread->startThread_lock();
850 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
851 sync_with_child->notify();
852 }
853
854 // Free Bsd resources related to the OSThread
855 void os::free_thread(OSThread* osthread) {
856 assert(osthread != NULL, "osthread not set");
857
858 // We are told to free resources of the argument thread,
859 // but we can only really operate on the current thread.
860 assert(Thread::current()->osthread() == osthread,
861 "os::free_thread but not current thread");
862
863 // Restore caller's signal mask
864 sigset_t sigmask = osthread->caller_sigmask();
865 pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
866
867 delete osthread;
868 }
869
870 ////////////////////////////////////////////////////////////////////////////////
871 // time support
872
873 // Time since start-up in seconds to a fine granularity.
874 // Used by VMSelfDestructTimer and the MemProfiler.
875 double os::elapsedTime() {
876
877 return ((double)os::elapsed_counter()) / os::elapsed_frequency();
878 }
879
880 jlong os::elapsed_counter() {
881 return javaTimeNanos() - initial_time_count;
882 }
883
884 jlong os::elapsed_frequency() {
885 return NANOSECS_PER_SEC; // nanosecond resolution
886 }
887
888 bool os::supports_vtime() { return true; }
889 bool os::enable_vtime() { return false; }
890 bool os::vtime_enabled() { return false; }
891
892 double os::elapsedVTime() {
893 // better than nothing, but not much
894 return elapsedTime();
895 }
896
897 jlong os::javaTimeMillis() {
898 timeval time;
899 int status = gettimeofday(&time, NULL);
900 assert(status != -1, "bsd error");
901 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
902 }
903
904 void os::javaTimeSystemUTC(jlong &seconds, jlong &nanos) {
905 timeval time;
906 int status = gettimeofday(&time, NULL);
907 assert(status != -1, "bsd error");
908 seconds = jlong(time.tv_sec);
909 nanos = jlong(time.tv_usec) * 1000;
910 }
911
912 #ifndef __APPLE__
913 #ifndef CLOCK_MONOTONIC
914 #define CLOCK_MONOTONIC (1)
915 #endif
916 #endif
917
918 #ifdef __APPLE__
919 void os::Bsd::clock_init() {
920 mach_timebase_info(&_timebase_info);
921 }
922 #else
923 void os::Bsd::clock_init() {
924 struct timespec res;
925 struct timespec tp;
926 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
927 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) {
928 // yes, monotonic clock is supported
929 _clock_gettime = ::clock_gettime;
930 }
931 }
932 #endif
933
934
935
936 #ifdef __APPLE__
937
938 jlong os::javaTimeNanos() {
939 const uint64_t tm = mach_absolute_time();
940 const uint64_t now = (tm * Bsd::_timebase_info.numer) / Bsd::_timebase_info.denom;
941 const uint64_t prev = Bsd::_max_abstime;
942 if (now <= prev) {
943 return prev; // same or retrograde time;
944 }
945 const uint64_t obsv = Atomic::cmpxchg(now, &Bsd::_max_abstime, prev);
946 assert(obsv >= prev, "invariant"); // Monotonicity
947 // If the CAS succeeded then we're done and return "now".
948 // If the CAS failed and the observed value "obsv" is >= now then
949 // we should return "obsv". If the CAS failed and now > obsv > prv then
950 // some other thread raced this thread and installed a new value, in which case
951 // we could either (a) retry the entire operation, (b) retry trying to install now
952 // or (c) just return obsv. We use (c). No loop is required although in some cases
953 // we might discard a higher "now" value in deference to a slightly lower but freshly
954 // installed obsv value. That's entirely benign -- it admits no new orderings compared
955 // to (a) or (b) -- and greatly reduces coherence traffic.
956 // We might also condition (c) on the magnitude of the delta between obsv and now.
957 // Avoiding excessive CAS operations to hot RW locations is critical.
958 // See https://blogs.oracle.com/dave/entry/cas_and_cache_trivia_invalidate
959 return (prev == obsv) ? now : obsv;
960 }
961
962 #else // __APPLE__
963
964 jlong os::javaTimeNanos() {
965 if (os::supports_monotonic_clock()) {
966 struct timespec tp;
967 int status = Bsd::_clock_gettime(CLOCK_MONOTONIC, &tp);
968 assert(status == 0, "gettime error");
969 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
970 return result;
971 } else {
972 timeval time;
973 int status = gettimeofday(&time, NULL);
974 assert(status != -1, "bsd error");
975 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
976 return 1000 * usecs;
977 }
978 }
979
980 #endif // __APPLE__
981
982 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
983 if (os::supports_monotonic_clock()) {
984 info_ptr->max_value = ALL_64_BITS;
985
986 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
987 info_ptr->may_skip_backward = false; // not subject to resetting or drifting
988 info_ptr->may_skip_forward = false; // not subject to resetting or drifting
989 } else {
990 // gettimeofday - based on time in seconds since the Epoch thus does not wrap
991 info_ptr->max_value = ALL_64_BITS;
992
993 // gettimeofday is a real time clock so it skips
994 info_ptr->may_skip_backward = true;
995 info_ptr->may_skip_forward = true;
996 }
997
998 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
999 }
1000
1001 // Return the real, user, and system times in seconds from an
1002 // arbitrary fixed point in the past.
1003 bool os::getTimesSecs(double* process_real_time,
1004 double* process_user_time,
1005 double* process_system_time) {
1006 struct tms ticks;
1007 clock_t real_ticks = times(&ticks);
1008
1009 if (real_ticks == (clock_t) (-1)) {
1010 return false;
1011 } else {
1012 double ticks_per_second = (double) clock_tics_per_sec;
1013 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1014 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1015 *process_real_time = ((double) real_ticks) / ticks_per_second;
1016
1017 return true;
1018 }
1019 }
1020
1021
1022 char * os::local_time_string(char *buf, size_t buflen) {
1023 struct tm t;
1024 time_t long_time;
1025 time(&long_time);
1026 localtime_r(&long_time, &t);
1027 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1028 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1029 t.tm_hour, t.tm_min, t.tm_sec);
1030 return buf;
1031 }
1032
1033 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
1034 return localtime_r(clock, res);
1035 }
1036
1037 ////////////////////////////////////////////////////////////////////////////////
1038 // runtime exit support
1039
1040 // Note: os::shutdown() might be called very early during initialization, or
1041 // called from signal handler. Before adding something to os::shutdown(), make
1042 // sure it is async-safe and can handle partially initialized VM.
1043 void os::shutdown() {
1044
1045 // allow PerfMemory to attempt cleanup of any persistent resources
1046 perfMemory_exit();
1047
1048 // needs to remove object in file system
1049 AttachListener::abort();
1050
1051 // flush buffered output, finish log files
1052 ostream_abort();
1053
1054 // Check for abort hook
1055 abort_hook_t abort_hook = Arguments::abort_hook();
1056 if (abort_hook != NULL) {
1057 abort_hook();
1058 }
1059
1060 }
1061
1062 // Note: os::abort() might be called very early during initialization, or
1063 // called from signal handler. Before adding something to os::abort(), make
1064 // sure it is async-safe and can handle partially initialized VM.
1065 void os::abort(bool dump_core, void* siginfo, const void* context) {
1066 os::shutdown();
1067 if (dump_core) {
1068 #ifndef PRODUCT
1069 fdStream out(defaultStream::output_fd());
1070 out.print_raw("Current thread is ");
1071 char buf[16];
1072 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
1073 out.print_raw_cr(buf);
1074 out.print_raw_cr("Dumping core ...");
1075 #endif
1076 ::abort(); // dump core
1077 }
1078
1079 ::exit(1);
1080 }
1081
1082 // Die immediately, no exit hook, no abort hook, no cleanup.
1083 void os::die() {
1084 // _exit() on BsdThreads only kills current thread
1085 ::abort();
1086 }
1087
1088 // This method is a copy of JDK's sysGetLastErrorString
1089 // from src/solaris/hpi/src/system_md.c
1090
1091 size_t os::lasterror(char *buf, size_t len) {
1092 if (errno == 0) return 0;
1093
1094 const char *s = os::strerror(errno);
1095 size_t n = ::strlen(s);
1096 if (n >= len) {
1097 n = len - 1;
1098 }
1099 ::strncpy(buf, s, n);
1100 buf[n] = '\0';
1101 return n;
1102 }
1103
1104 // Information of current thread in variety of formats
1105 pid_t os::Bsd::gettid() {
1106 int retval = -1;
1107
1108 #ifdef __APPLE__ //XNU kernel
1109 // despite the fact mach port is actually not a thread id use it
1110 // instead of syscall(SYS_thread_selfid) as it certainly fits to u4
1111 retval = ::pthread_mach_thread_np(::pthread_self());
1112 guarantee(retval != 0, "just checking");
1113 return retval;
1114
1115 #else
1116 #ifdef __FreeBSD__
1117 retval = syscall(SYS_thr_self);
1118 #else
1119 #ifdef __OpenBSD__
1120 retval = syscall(SYS_getthrid);
1121 #else
1122 #ifdef __NetBSD__
1123 retval = (pid_t) syscall(SYS__lwp_self);
1124 #endif
1125 #endif
1126 #endif
1127 #endif
1128
1129 if (retval == -1) {
1130 return getpid();
1131 }
1132 }
1133
1134 intx os::current_thread_id() {
1135 #ifdef __APPLE__
1136 return (intx)::pthread_mach_thread_np(::pthread_self());
1137 #else
1138 return (intx)::pthread_self();
1139 #endif
1140 }
1141
1142 int os::current_process_id() {
1143
1144 // Under the old bsd thread library, bsd gives each thread
1145 // its own process id. Because of this each thread will return
1146 // a different pid if this method were to return the result
1147 // of getpid(2). Bsd provides no api that returns the pid
1148 // of the launcher thread for the vm. This implementation
1149 // returns a unique pid, the pid of the launcher thread
1150 // that starts the vm 'process'.
1151
1152 // Under the NPTL, getpid() returns the same pid as the
1153 // launcher thread rather than a unique pid per thread.
1154 // Use gettid() if you want the old pre NPTL behaviour.
1155
1156 // if you are looking for the result of a call to getpid() that
1157 // returns a unique pid for the calling thread, then look at the
1158 // OSThread::thread_id() method in osThread_bsd.hpp file
1159
1160 return (int)(_initial_pid ? _initial_pid : getpid());
1161 }
1162
1163 // DLL functions
1164
1165 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1166
1167 // This must be hard coded because it's the system's temporary
1168 // directory not the java application's temp directory, ala java.io.tmpdir.
1169 #ifdef __APPLE__
1170 // macosx has a secure per-user temporary directory
1171 char temp_path_storage[PATH_MAX];
1172 const char* os::get_temp_directory() {
1173 static char *temp_path = NULL;
1174 if (temp_path == NULL) {
1175 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
1176 if (pathSize == 0 || pathSize > PATH_MAX) {
1177 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
1178 }
1179 temp_path = temp_path_storage;
1180 }
1181 return temp_path;
1182 }
1183 #else // __APPLE__
1184 const char* os::get_temp_directory() { return "/tmp"; }
1185 #endif // __APPLE__
1186
1187 // check if addr is inside libjvm.so
1188 bool os::address_is_in_vm(address addr) {
1189 static address libjvm_base_addr;
1190 Dl_info dlinfo;
1191
1192 if (libjvm_base_addr == NULL) {
1193 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) {
1194 libjvm_base_addr = (address)dlinfo.dli_fbase;
1195 }
1196 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1197 }
1198
1199 if (dladdr((void *)addr, &dlinfo) != 0) {
1200 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1201 }
1202
1203 return false;
1204 }
1205
1206
1207 #define MACH_MAXSYMLEN 256
1208
1209 bool os::dll_address_to_function_name(address addr, char *buf,
1210 int buflen, int *offset,
1211 bool demangle) {
1212 // buf is not optional, but offset is optional
1213 assert(buf != NULL, "sanity check");
1214
1215 Dl_info dlinfo;
1216 char localbuf[MACH_MAXSYMLEN];
1217
1218 if (dladdr((void*)addr, &dlinfo) != 0) {
1219 // see if we have a matching symbol
1220 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) {
1221 if (!(demangle && Decoder::demangle(dlinfo.dli_sname, buf, buflen))) {
1222 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1223 }
1224 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1225 return true;
1226 }
1227 // no matching symbol so try for just file info
1228 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) {
1229 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1230 buf, buflen, offset, dlinfo.dli_fname, demangle)) {
1231 return true;
1232 }
1233 }
1234
1235 // Handle non-dynamic manually:
1236 if (dlinfo.dli_fbase != NULL &&
1237 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset,
1238 dlinfo.dli_fbase)) {
1239 if (!(demangle && Decoder::demangle(localbuf, buf, buflen))) {
1240 jio_snprintf(buf, buflen, "%s", localbuf);
1241 }
1242 return true;
1243 }
1244 }
1245 buf[0] = '\0';
1246 if (offset != NULL) *offset = -1;
1247 return false;
1248 }
1249
1250 // ported from solaris version
1251 bool os::dll_address_to_library_name(address addr, char* buf,
1252 int buflen, int* offset) {
1253 // buf is not optional, but offset is optional
1254 assert(buf != NULL, "sanity check");
1255
1256 Dl_info dlinfo;
1257
1258 if (dladdr((void*)addr, &dlinfo) != 0) {
1259 if (dlinfo.dli_fname != NULL) {
1260 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1261 }
1262 if (dlinfo.dli_fbase != NULL && offset != NULL) {
1263 *offset = addr - (address)dlinfo.dli_fbase;
1264 }
1265 return true;
1266 }
1267
1268 buf[0] = '\0';
1269 if (offset) *offset = -1;
1270 return false;
1271 }
1272
1273 // Loads .dll/.so and
1274 // in case of error it checks if .dll/.so was built for the
1275 // same architecture as Hotspot is running on
1276
1277 #ifdef __APPLE__
1278 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1279 #ifdef STATIC_BUILD
1280 return os::get_default_process_handle();
1281 #else
1282 void * result= ::dlopen(filename, RTLD_LAZY);
1283 if (result != NULL) {
1284 // Successful loading
1285 return result;
1286 }
1287
1288 // Read system error message into ebuf
1289 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1290 ebuf[ebuflen-1]='\0';
1291
1292 return NULL;
1293 #endif // STATIC_BUILD
1294 }
1295 #else
1296 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1297 #ifdef STATIC_BUILD
1298 return os::get_default_process_handle();
1299 #else
1300 void * result= ::dlopen(filename, RTLD_LAZY);
1301 if (result != NULL) {
1302 // Successful loading
1303 return result;
1304 }
1305
1306 Elf32_Ehdr elf_head;
1307
1308 // Read system error message into ebuf
1309 // It may or may not be overwritten below
1310 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1311 ebuf[ebuflen-1]='\0';
1312 int diag_msg_max_length=ebuflen-strlen(ebuf);
1313 char* diag_msg_buf=ebuf+strlen(ebuf);
1314
1315 if (diag_msg_max_length==0) {
1316 // No more space in ebuf for additional diagnostics message
1317 return NULL;
1318 }
1319
1320
1321 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1322
1323 if (file_descriptor < 0) {
1324 // Can't open library, report dlerror() message
1325 return NULL;
1326 }
1327
1328 bool failed_to_read_elf_head=
1329 (sizeof(elf_head)!=
1330 (::read(file_descriptor, &elf_head,sizeof(elf_head))));
1331
1332 ::close(file_descriptor);
1333 if (failed_to_read_elf_head) {
1334 // file i/o error - report dlerror() msg
1335 return NULL;
1336 }
1337
1338 typedef struct {
1339 Elf32_Half code; // Actual value as defined in elf.h
1340 Elf32_Half compat_class; // Compatibility of archs at VM's sense
1341 char elf_class; // 32 or 64 bit
1342 char endianess; // MSB or LSB
1343 char* name; // String representation
1344 } arch_t;
1345
1346 #ifndef EM_486
1347 #define EM_486 6 /* Intel 80486 */
1348 #endif
1349
1350 #ifndef EM_MIPS_RS3_LE
1351 #define EM_MIPS_RS3_LE 10 /* MIPS */
1352 #endif
1353
1354 #ifndef EM_PPC64
1355 #define EM_PPC64 21 /* PowerPC64 */
1356 #endif
1357
1358 #ifndef EM_S390
1359 #define EM_S390 22 /* IBM System/390 */
1360 #endif
1361
1362 #ifndef EM_IA_64
1363 #define EM_IA_64 50 /* HP/Intel IA-64 */
1364 #endif
1365
1366 #ifndef EM_X86_64
1367 #define EM_X86_64 62 /* AMD x86-64 */
1368 #endif
1369
1370 static const arch_t arch_array[]={
1371 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1372 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1373 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
1374 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
1375 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1376 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1377 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
1378 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
1379 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
1380 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"},
1381 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
1382 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
1383 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
1384 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
1385 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
1386 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
1387 };
1388
1389 #if (defined IA32)
1390 static Elf32_Half running_arch_code=EM_386;
1391 #elif (defined AMD64)
1392 static Elf32_Half running_arch_code=EM_X86_64;
1393 #elif (defined IA64)
1394 static Elf32_Half running_arch_code=EM_IA_64;
1395 #elif (defined __sparc) && (defined _LP64)
1396 static Elf32_Half running_arch_code=EM_SPARCV9;
1397 #elif (defined __sparc) && (!defined _LP64)
1398 static Elf32_Half running_arch_code=EM_SPARC;
1399 #elif (defined __powerpc64__)
1400 static Elf32_Half running_arch_code=EM_PPC64;
1401 #elif (defined __powerpc__)
1402 static Elf32_Half running_arch_code=EM_PPC;
1403 #elif (defined ARM)
1404 static Elf32_Half running_arch_code=EM_ARM;
1405 #elif (defined S390)
1406 static Elf32_Half running_arch_code=EM_S390;
1407 #elif (defined ALPHA)
1408 static Elf32_Half running_arch_code=EM_ALPHA;
1409 #elif (defined MIPSEL)
1410 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
1411 #elif (defined PARISC)
1412 static Elf32_Half running_arch_code=EM_PARISC;
1413 #elif (defined MIPS)
1414 static Elf32_Half running_arch_code=EM_MIPS;
1415 #elif (defined M68K)
1416 static Elf32_Half running_arch_code=EM_68K;
1417 #else
1418 #error Method os::dll_load requires that one of following is defined:\
1419 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
1420 #endif
1421
1422 // Identify compatability class for VM's architecture and library's architecture
1423 // Obtain string descriptions for architectures
1424
1425 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
1426 int running_arch_index=-1;
1427
1428 for (unsigned int i=0; i < ARRAY_SIZE(arch_array); i++) {
1429 if (running_arch_code == arch_array[i].code) {
1430 running_arch_index = i;
1431 }
1432 if (lib_arch.code == arch_array[i].code) {
1433 lib_arch.compat_class = arch_array[i].compat_class;
1434 lib_arch.name = arch_array[i].name;
1435 }
1436 }
1437
1438 assert(running_arch_index != -1,
1439 "Didn't find running architecture code (running_arch_code) in arch_array");
1440 if (running_arch_index == -1) {
1441 // Even though running architecture detection failed
1442 // we may still continue with reporting dlerror() message
1443 return NULL;
1444 }
1445
1446 if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
1447 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
1448 return NULL;
1449 }
1450
1451 #ifndef S390
1452 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
1453 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
1454 return NULL;
1455 }
1456 #endif // !S390
1457
1458 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
1459 if (lib_arch.name!=NULL) {
1460 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1461 " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
1462 lib_arch.name, arch_array[running_arch_index].name);
1463 } else {
1464 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1465 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
1466 lib_arch.code,
1467 arch_array[running_arch_index].name);
1468 }
1469 }
1470
1471 return NULL;
1472 #endif // STATIC_BUILD
1473 }
1474 #endif // !__APPLE__
1475
1476 void* os::get_default_process_handle() {
1477 #ifdef __APPLE__
1478 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY
1479 // to avoid finding unexpected symbols on second (or later)
1480 // loads of a library.
1481 return (void*)::dlopen(NULL, RTLD_FIRST);
1482 #else
1483 return (void*)::dlopen(NULL, RTLD_LAZY);
1484 #endif
1485 }
1486
1487 // XXX: Do we need a lock around this as per Linux?
1488 void* os::dll_lookup(void* handle, const char* name) {
1489 return dlsym(handle, name);
1490 }
1491
1492 int _print_dll_info_cb(const char * name, address base_address, address top_address, void * param) {
1493 outputStream * out = (outputStream *) param;
1494 out->print_cr(INTPTR_FORMAT " \t%s", (intptr_t)base_address, name);
1495 return 0;
1496 }
1497
1498 void os::print_dll_info(outputStream *st) {
1499 st->print_cr("Dynamic libraries:");
1500 if (get_loaded_modules_info(_print_dll_info_cb, (void *)st)) {
1501 st->print_cr("Error: Cannot print dynamic libraries.");
1502 }
1503 }
1504
1505 int os::get_loaded_modules_info(os::LoadedModulesCallbackFunc callback, void *param) {
1506 #ifdef RTLD_DI_LINKMAP
1507 Dl_info dli;
1508 void *handle;
1509 Link_map *map;
1510 Link_map *p;
1511
1512 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 ||
1513 dli.dli_fname == NULL) {
1514 return 1;
1515 }
1516 handle = dlopen(dli.dli_fname, RTLD_LAZY);
1517 if (handle == NULL) {
1518 return 1;
1519 }
1520 dlinfo(handle, RTLD_DI_LINKMAP, &map);
1521 if (map == NULL) {
1522 dlclose(handle);
1523 return 1;
1524 }
1525
1526 while (map->l_prev != NULL)
1527 map = map->l_prev;
1528
1529 while (map != NULL) {
1530 // Value for top_address is returned as 0 since we don't have any information about module size
1531 if (callback(map->l_name, (address)map->l_addr, (address)0, param)) {
1532 dlclose(handle);
1533 return 1;
1534 }
1535 map = map->l_next;
1536 }
1537
1538 dlclose(handle);
1539 #elif defined(__APPLE__)
1540 for (uint32_t i = 1; i < _dyld_image_count(); i++) {
1541 // Value for top_address is returned as 0 since we don't have any information about module size
1542 if (callback(_dyld_get_image_name(i), (address)_dyld_get_image_header(i), (address)0, param)) {
1543 return 1;
1544 }
1545 }
1546 return 0;
1547 #else
1548 return 1;
1549 #endif
1550 }
1551
1552 void os::get_summary_os_info(char* buf, size_t buflen) {
1553 // These buffers are small because we want this to be brief
1554 // and not use a lot of stack while generating the hs_err file.
1555 char os[100];
1556 size_t size = sizeof(os);
1557 int mib_kern[] = { CTL_KERN, KERN_OSTYPE };
1558 if (sysctl(mib_kern, 2, os, &size, NULL, 0) < 0) {
1559 #ifdef __APPLE__
1560 strncpy(os, "Darwin", sizeof(os));
1561 #elif __OpenBSD__
1562 strncpy(os, "OpenBSD", sizeof(os));
1563 #else
1564 strncpy(os, "BSD", sizeof(os));
1565 #endif
1566 }
1567
1568 char release[100];
1569 size = sizeof(release);
1570 int mib_release[] = { CTL_KERN, KERN_OSRELEASE };
1571 if (sysctl(mib_release, 2, release, &size, NULL, 0) < 0) {
1572 // if error, leave blank
1573 strncpy(release, "", sizeof(release));
1574 }
1575 snprintf(buf, buflen, "%s %s", os, release);
1576 }
1577
1578 void os::print_os_info_brief(outputStream* st) {
1579 os::Posix::print_uname_info(st);
1580 }
1581
1582 void os::print_os_info(outputStream* st) {
1583 st->print("OS:");
1584
1585 os::Posix::print_uname_info(st);
1586
1587 os::Posix::print_rlimit_info(st);
1588
1589 os::Posix::print_load_average(st);
1590 }
1591
1592 void os::pd_print_cpu_info(outputStream* st, char* buf, size_t buflen) {
1593 // Nothing to do for now.
1594 }
1595
1596 void os::get_summary_cpu_info(char* buf, size_t buflen) {
1597 unsigned int mhz;
1598 size_t size = sizeof(mhz);
1599 int mib[] = { CTL_HW, HW_CPU_FREQ };
1600 if (sysctl(mib, 2, &mhz, &size, NULL, 0) < 0) {
1601 mhz = 1; // looks like an error but can be divided by
1602 } else {
1603 mhz /= 1000000; // reported in millions
1604 }
1605
1606 char model[100];
1607 size = sizeof(model);
1608 int mib_model[] = { CTL_HW, HW_MODEL };
1609 if (sysctl(mib_model, 2, model, &size, NULL, 0) < 0) {
1610 strncpy(model, cpu_arch, sizeof(model));
1611 }
1612
1613 char machine[100];
1614 size = sizeof(machine);
1615 int mib_machine[] = { CTL_HW, HW_MACHINE };
1616 if (sysctl(mib_machine, 2, machine, &size, NULL, 0) < 0) {
1617 strncpy(machine, "", sizeof(machine));
1618 }
1619
1620 snprintf(buf, buflen, "%s %s %d MHz", model, machine, mhz);
1621 }
1622
1623 void os::print_memory_info(outputStream* st) {
1624 xsw_usage swap_usage;
1625 size_t size = sizeof(swap_usage);
1626
1627 st->print("Memory:");
1628 st->print(" %dk page", os::vm_page_size()>>10);
1629
1630 st->print(", physical " UINT64_FORMAT "k",
1631 os::physical_memory() >> 10);
1632 st->print("(" UINT64_FORMAT "k free)",
1633 os::available_memory() >> 10);
1634
1635 if((sysctlbyname("vm.swapusage", &swap_usage, &size, NULL, 0) == 0) || (errno == ENOMEM)) {
1636 if (size >= offset_of(xsw_usage, xsu_used)) {
1637 st->print(", swap " UINT64_FORMAT "k",
1638 ((julong) swap_usage.xsu_total) >> 10);
1639 st->print("(" UINT64_FORMAT "k free)",
1640 ((julong) swap_usage.xsu_avail) >> 10);
1641 }
1642 }
1643
1644 st->cr();
1645 }
1646
1647 static void print_signal_handler(outputStream* st, int sig,
1648 char* buf, size_t buflen);
1649
1650 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1651 st->print_cr("Signal Handlers:");
1652 print_signal_handler(st, SIGSEGV, buf, buflen);
1653 print_signal_handler(st, SIGBUS , buf, buflen);
1654 print_signal_handler(st, SIGFPE , buf, buflen);
1655 print_signal_handler(st, SIGPIPE, buf, buflen);
1656 print_signal_handler(st, SIGXFSZ, buf, buflen);
1657 print_signal_handler(st, SIGILL , buf, buflen);
1658 print_signal_handler(st, SR_signum, buf, buflen);
1659 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1660 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1661 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1662 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1663 }
1664
1665 static char saved_jvm_path[MAXPATHLEN] = {0};
1666
1667 // Find the full path to the current module, libjvm
1668 void os::jvm_path(char *buf, jint buflen) {
1669 // Error checking.
1670 if (buflen < MAXPATHLEN) {
1671 assert(false, "must use a large-enough buffer");
1672 buf[0] = '\0';
1673 return;
1674 }
1675 // Lazy resolve the path to current module.
1676 if (saved_jvm_path[0] != 0) {
1677 strcpy(buf, saved_jvm_path);
1678 return;
1679 }
1680
1681 char dli_fname[MAXPATHLEN];
1682 bool ret = dll_address_to_library_name(
1683 CAST_FROM_FN_PTR(address, os::jvm_path),
1684 dli_fname, sizeof(dli_fname), NULL);
1685 assert(ret, "cannot locate libjvm");
1686 char *rp = NULL;
1687 if (ret && dli_fname[0] != '\0') {
1688 rp = os::Posix::realpath(dli_fname, buf, buflen);
1689 }
1690 if (rp == NULL) {
1691 return;
1692 }
1693
1694 if (Arguments::sun_java_launcher_is_altjvm()) {
1695 // Support for the java launcher's '-XXaltjvm=<path>' option. Typical
1696 // value for buf is "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so"
1697 // or "<JAVA_HOME>/jre/lib/<vmtype>/libjvm.dylib". If "/jre/lib/"
1698 // appears at the right place in the string, then assume we are
1699 // installed in a JDK and we're done. Otherwise, check for a
1700 // JAVA_HOME environment variable and construct a path to the JVM
1701 // being overridden.
1702
1703 const char *p = buf + strlen(buf) - 1;
1704 for (int count = 0; p > buf && count < 5; ++count) {
1705 for (--p; p > buf && *p != '/'; --p)
1706 /* empty */ ;
1707 }
1708
1709 if (strncmp(p, "/jre/lib/", 9) != 0) {
1710 // Look for JAVA_HOME in the environment.
1711 char* java_home_var = ::getenv("JAVA_HOME");
1712 if (java_home_var != NULL && java_home_var[0] != 0) {
1713 char* jrelib_p;
1714 int len;
1715
1716 // Check the current module name "libjvm"
1717 p = strrchr(buf, '/');
1718 assert(strstr(p, "/libjvm") == p, "invalid library name");
1719
1720 rp = os::Posix::realpath(java_home_var, buf, buflen);
1721 if (rp == NULL) {
1722 return;
1723 }
1724
1725 // determine if this is a legacy image or modules image
1726 // modules image doesn't have "jre" subdirectory
1727 len = strlen(buf);
1728 assert(len < buflen, "Ran out of buffer space");
1729 jrelib_p = buf + len;
1730
1731 // Add the appropriate library subdir
1732 snprintf(jrelib_p, buflen-len, "/jre/lib");
1733 if (0 != access(buf, F_OK)) {
1734 snprintf(jrelib_p, buflen-len, "/lib");
1735 }
1736
1737 // Add the appropriate client or server subdir
1738 len = strlen(buf);
1739 jrelib_p = buf + len;
1740 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
1741 if (0 != access(buf, F_OK)) {
1742 snprintf(jrelib_p, buflen-len, "%s", "");
1743 }
1744
1745 // If the path exists within JAVA_HOME, add the JVM library name
1746 // to complete the path to JVM being overridden. Otherwise fallback
1747 // to the path to the current library.
1748 if (0 == access(buf, F_OK)) {
1749 // Use current module name "libjvm"
1750 len = strlen(buf);
1751 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
1752 } else {
1753 // Fall back to path of current library
1754 rp = os::Posix::realpath(dli_fname, buf, buflen);
1755 if (rp == NULL) {
1756 return;
1757 }
1758 }
1759 }
1760 }
1761 }
1762
1763 strncpy(saved_jvm_path, buf, MAXPATHLEN);
1764 saved_jvm_path[MAXPATHLEN - 1] = '\0';
1765 }
1766
1767 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1768 // no prefix required, not even "_"
1769 }
1770
1771 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1772 // no suffix required
1773 }
1774
1775 ////////////////////////////////////////////////////////////////////////////////
1776 // sun.misc.Signal support
1777
1778 static volatile jint sigint_count = 0;
1779
1780 static void UserHandler(int sig, void *siginfo, void *context) {
1781 // 4511530 - sem_post is serialized and handled by the manager thread. When
1782 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
1783 // don't want to flood the manager thread with sem_post requests.
1784 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1) {
1785 return;
1786 }
1787
1788 // Ctrl-C is pressed during error reporting, likely because the error
1789 // handler fails to abort. Let VM die immediately.
1790 if (sig == SIGINT && VMError::is_error_reported()) {
1791 os::die();
1792 }
1793
1794 os::signal_notify(sig);
1795 }
1796
1797 void* os::user_handler() {
1798 return CAST_FROM_FN_PTR(void*, UserHandler);
1799 }
1800
1801 extern "C" {
1802 typedef void (*sa_handler_t)(int);
1803 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1804 }
1805
1806 void* os::signal(int signal_number, void* handler) {
1807 struct sigaction sigAct, oldSigAct;
1808
1809 sigfillset(&(sigAct.sa_mask));
1810 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
1811 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1812
1813 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1814 // -1 means registration failed
1815 return (void *)-1;
1816 }
1817
1818 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1819 }
1820
1821 void os::signal_raise(int signal_number) {
1822 ::raise(signal_number);
1823 }
1824
1825 // The following code is moved from os.cpp for making this
1826 // code platform specific, which it is by its very nature.
1827
1828 // Will be modified when max signal is changed to be dynamic
1829 int os::sigexitnum_pd() {
1830 return NSIG;
1831 }
1832
1833 // a counter for each possible signal value
1834 static volatile jint pending_signals[NSIG+1] = { 0 };
1835 static Semaphore* sig_sem = NULL;
1836
1837 static void jdk_misc_signal_init() {
1838 // Initialize signal structures
1839 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
1840
1841 // Initialize signal semaphore
1842 sig_sem = new Semaphore();
1843 }
1844
1845 void os::signal_notify(int sig) {
1846 if (sig_sem != NULL) {
1847 Atomic::inc(&pending_signals[sig]);
1848 sig_sem->signal();
1849 } else {
1850 // Signal thread is not created with ReduceSignalUsage and jdk_misc_signal_init
1851 // initialization isn't called.
1852 assert(ReduceSignalUsage, "signal semaphore should be created");
1853 }
1854 }
1855
1856 static int check_pending_signals() {
1857 Atomic::store(0, &sigint_count);
1858 for (;;) {
1859 for (int i = 0; i < NSIG + 1; i++) {
1860 jint n = pending_signals[i];
1861 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
1862 return i;
1863 }
1864 }
1865 JavaThread *thread = JavaThread::current();
1866 ThreadBlockInVM tbivm(thread);
1867
1868 bool threadIsSuspended;
1869 do {
1870 thread->set_suspend_equivalent();
1871 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
1872 sig_sem->wait();
1873
1874 // were we externally suspended while we were waiting?
1875 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
1876 if (threadIsSuspended) {
1877 // The semaphore has been incremented, but while we were waiting
1878 // another thread suspended us. We don't want to continue running
1879 // while suspended because that would surprise the thread that
1880 // suspended us.
1881 sig_sem->signal();
1882
1883 thread->java_suspend_self();
1884 }
1885 } while (threadIsSuspended);
1886 }
1887 }
1888
1889 int os::signal_wait() {
1890 return check_pending_signals();
1891 }
1892
1893 ////////////////////////////////////////////////////////////////////////////////
1894 // Virtual Memory
1895
1896 int os::vm_page_size() {
1897 // Seems redundant as all get out
1898 assert(os::Bsd::page_size() != -1, "must call os::init");
1899 return os::Bsd::page_size();
1900 }
1901
1902 // Solaris allocates memory by pages.
1903 int os::vm_allocation_granularity() {
1904 assert(os::Bsd::page_size() != -1, "must call os::init");
1905 return os::Bsd::page_size();
1906 }
1907
1908 // Rationale behind this function:
1909 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
1910 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
1911 // samples for JITted code. Here we create private executable mapping over the code cache
1912 // and then we can use standard (well, almost, as mapping can change) way to provide
1913 // info for the reporting script by storing timestamp and location of symbol
1914 void bsd_wrap_code(char* base, size_t size) {
1915 static volatile jint cnt = 0;
1916
1917 if (!UseOprofile) {
1918 return;
1919 }
1920
1921 char buf[PATH_MAX + 1];
1922 int num = Atomic::add(1, &cnt);
1923
1924 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
1925 os::get_temp_directory(), os::current_process_id(), num);
1926 unlink(buf);
1927
1928 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
1929
1930 if (fd != -1) {
1931 off_t rv = ::lseek(fd, size-2, SEEK_SET);
1932 if (rv != (off_t)-1) {
1933 if (::write(fd, "", 1) == 1) {
1934 mmap(base, size,
1935 PROT_READ|PROT_WRITE|PROT_EXEC,
1936 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
1937 }
1938 }
1939 ::close(fd);
1940 unlink(buf);
1941 }
1942 }
1943
1944 static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
1945 int err) {
1946 warning("INFO: os::commit_memory(" INTPTR_FORMAT ", " SIZE_FORMAT
1947 ", %d) failed; error='%s' (errno=%d)", (intptr_t)addr, size, exec,
1948 os::errno_name(err), err);
1949 }
1950
1951 // NOTE: Bsd kernel does not really reserve the pages for us.
1952 // All it does is to check if there are enough free pages
1953 // left at the time of mmap(). This could be a potential
1954 // problem.
1955 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
1956 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
1957 #ifdef __OpenBSD__
1958 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
1959 if (::mprotect(addr, size, prot) == 0) {
1960 return true;
1961 }
1962 #else
1963 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
1964 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
1965 if (res != (uintptr_t) MAP_FAILED) {
1966 return true;
1967 }
1968 #endif
1969
1970 // Warn about any commit errors we see in non-product builds just
1971 // in case mmap() doesn't work as described on the man page.
1972 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);)
1973
1974 return false;
1975 }
1976
1977 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
1978 bool exec) {
1979 // alignment_hint is ignored on this OS
1980 return pd_commit_memory(addr, size, exec);
1981 }
1982
1983 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
1984 const char* mesg) {
1985 assert(mesg != NULL, "mesg must be specified");
1986 if (!pd_commit_memory(addr, size, exec)) {
1987 // add extra info in product mode for vm_exit_out_of_memory():
1988 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
1989 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, "%s", mesg);
1990 }
1991 }
1992
1993 void os::pd_commit_memory_or_exit(char* addr, size_t size,
1994 size_t alignment_hint, bool exec,
1995 const char* mesg) {
1996 // alignment_hint is ignored on this OS
1997 pd_commit_memory_or_exit(addr, size, exec, mesg);
1998 }
1999
2000 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
2001 }
2002
2003 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
2004 ::madvise(addr, bytes, MADV_DONTNEED);
2005 }
2006
2007 void os::numa_make_global(char *addr, size_t bytes) {
2008 }
2009
2010 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
2011 }
2012
2013 bool os::numa_topology_changed() { return false; }
2014
2015 size_t os::numa_get_groups_num() {
2016 return 1;
2017 }
2018
2019 int os::numa_get_group_id() {
2020 return 0;
2021 }
2022
2023 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
2024 if (size > 0) {
2025 ids[0] = 0;
2026 return 1;
2027 }
2028 return 0;
2029 }
2030
2031 bool os::get_page_info(char *start, page_info* info) {
2032 return false;
2033 }
2034
2035 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2036 return end;
2037 }
2038
2039
2040 bool os::pd_uncommit_memory(char* addr, size_t size) {
2041 #ifdef __OpenBSD__
2042 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2043 return ::mprotect(addr, size, PROT_NONE) == 0;
2044 #else
2045 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
2046 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
2047 return res != (uintptr_t) MAP_FAILED;
2048 #endif
2049 }
2050
2051 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2052 return os::commit_memory(addr, size, !ExecMem);
2053 }
2054
2055 // If this is a growable mapping, remove the guard pages entirely by
2056 // munmap()ping them. If not, just call uncommit_memory().
2057 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2058 return os::uncommit_memory(addr, size);
2059 }
2060
2061 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2062 // at 'requested_addr'. If there are existing memory mappings at the same
2063 // location, however, they will be overwritten. If 'fixed' is false,
2064 // 'requested_addr' is only treated as a hint, the return value may or
2065 // may not start from the requested address. Unlike Bsd mmap(), this
2066 // function returns NULL to indicate failure.
2067 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2068 char * addr;
2069 int flags;
2070
2071 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2072 if (fixed) {
2073 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2074 flags |= MAP_FIXED;
2075 }
2076
2077 // Map reserved/uncommitted pages PROT_NONE so we fail early if we
2078 // touch an uncommitted page. Otherwise, the read/write might
2079 // succeed if we have enough swap space to back the physical page.
2080 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE,
2081 flags, -1, 0);
2082
2083 return addr == MAP_FAILED ? NULL : addr;
2084 }
2085
2086 static int anon_munmap(char * addr, size_t size) {
2087 return ::munmap(addr, size) == 0;
2088 }
2089
2090 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
2091 size_t alignment_hint) {
2092 return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2093 }
2094
2095 bool os::pd_release_memory(char* addr, size_t size) {
2096 return anon_munmap(addr, size);
2097 }
2098
2099 static bool bsd_mprotect(char* addr, size_t size, int prot) {
2100 // Bsd wants the mprotect address argument to be page aligned.
2101 char* bottom = (char*)align_down((intptr_t)addr, os::Bsd::page_size());
2102
2103 // According to SUSv3, mprotect() should only be used with mappings
2104 // established by mmap(), and mmap() always maps whole pages. Unaligned
2105 // 'addr' likely indicates problem in the VM (e.g. trying to change
2106 // protection of malloc'ed or statically allocated memory). Check the
2107 // caller if you hit this assert.
2108 assert(addr == bottom, "sanity check");
2109
2110 size = align_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2111 return ::mprotect(bottom, size, prot) == 0;
2112 }
2113
2114 // Set protections specified
2115 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2116 bool is_committed) {
2117 unsigned int p = 0;
2118 switch (prot) {
2119 case MEM_PROT_NONE: p = PROT_NONE; break;
2120 case MEM_PROT_READ: p = PROT_READ; break;
2121 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
2122 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2123 default:
2124 ShouldNotReachHere();
2125 }
2126 // is_committed is unused.
2127 return bsd_mprotect(addr, bytes, p);
2128 }
2129
2130 bool os::guard_memory(char* addr, size_t size) {
2131 return bsd_mprotect(addr, size, PROT_NONE);
2132 }
2133
2134 bool os::unguard_memory(char* addr, size_t size) {
2135 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
2136 }
2137
2138 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
2139 return false;
2140 }
2141
2142 // Large page support
2143
2144 static size_t _large_page_size = 0;
2145
2146 void os::large_page_init() {
2147 }
2148
2149
2150 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) {
2151 fatal("This code is not used or maintained.");
2152
2153 // "exec" is passed in but not used. Creating the shared image for
2154 // the code cache doesn't have an SHM_X executable permission to check.
2155 assert(UseLargePages && UseSHM, "only for SHM large pages");
2156
2157 key_t key = IPC_PRIVATE;
2158 char *addr;
2159
2160 bool warn_on_failure = UseLargePages &&
2161 (!FLAG_IS_DEFAULT(UseLargePages) ||
2162 !FLAG_IS_DEFAULT(LargePageSizeInBytes));
2163
2164 // Create a large shared memory region to attach to based on size.
2165 // Currently, size is the total size of the heap
2166 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W);
2167 if (shmid == -1) {
2168 // Possible reasons for shmget failure:
2169 // 1. shmmax is too small for Java heap.
2170 // > check shmmax value: cat /proc/sys/kernel/shmmax
2171 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax
2172 // 2. not enough large page memory.
2173 // > check available large pages: cat /proc/meminfo
2174 // > increase amount of large pages:
2175 // echo new_value > /proc/sys/vm/nr_hugepages
2176 // Note 1: different Bsd may use different name for this property,
2177 // e.g. on Redhat AS-3 it is "hugetlb_pool".
2178 // Note 2: it's possible there's enough physical memory available but
2179 // they are so fragmented after a long run that they can't
2180 // coalesce into large pages. Try to reserve large pages when
2181 // the system is still "fresh".
2182 if (warn_on_failure) {
2183 warning("Failed to reserve shared memory (errno = %d).", errno);
2184 }
2185 return NULL;
2186 }
2187
2188 // attach to the region
2189 addr = (char*)shmat(shmid, req_addr, 0);
2190 int err = errno;
2191
2192 // Remove shmid. If shmat() is successful, the actual shared memory segment
2193 // will be deleted when it's detached by shmdt() or when the process
2194 // terminates. If shmat() is not successful this will remove the shared
2195 // segment immediately.
2196 shmctl(shmid, IPC_RMID, NULL);
2197
2198 if ((intptr_t)addr == -1) {
2199 if (warn_on_failure) {
2200 warning("Failed to attach shared memory (errno = %d).", err);
2201 }
2202 return NULL;
2203 }
2204
2205 // The memory is committed
2206 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, CALLER_PC);
2207
2208 return addr;
2209 }
2210
2211 bool os::release_memory_special(char* base, size_t bytes) {
2212 if (MemTracker::tracking_level() > NMT_minimal) {
2213 Tracker tkr(Tracker::release);
2214 // detaching the SHM segment will also delete it, see reserve_memory_special()
2215 int rslt = shmdt(base);
2216 if (rslt == 0) {
2217 tkr.record((address)base, bytes);
2218 return true;
2219 } else {
2220 return false;
2221 }
2222 } else {
2223 return shmdt(base) == 0;
2224 }
2225 }
2226
2227 size_t os::large_page_size() {
2228 return _large_page_size;
2229 }
2230
2231 // HugeTLBFS allows application to commit large page memory on demand;
2232 // with SysV SHM the entire memory region must be allocated as shared
2233 // memory.
2234 bool os::can_commit_large_page_memory() {
2235 return UseHugeTLBFS;
2236 }
2237
2238 bool os::can_execute_large_page_memory() {
2239 return UseHugeTLBFS;
2240 }
2241
2242 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr, int file_desc) {
2243 assert(file_desc >= 0, "file_desc is not valid");
2244 char* result = pd_attempt_reserve_memory_at(bytes, requested_addr);
2245 if (result != NULL) {
2246 if (replace_existing_mapping_with_file_mapping(result, bytes, file_desc) == NULL) {
2247 vm_exit_during_initialization(err_msg("Error in mapping Java heap at the given filesystem directory"));
2248 }
2249 }
2250 return result;
2251 }
2252
2253 // Reserve memory at an arbitrary address, only if that area is
2254 // available (and not reserved for something else).
2255
2256 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2257 const int max_tries = 10;
2258 char* base[max_tries];
2259 size_t size[max_tries];
2260 const size_t gap = 0x000000;
2261
2262 // Assert only that the size is a multiple of the page size, since
2263 // that's all that mmap requires, and since that's all we really know
2264 // about at this low abstraction level. If we need higher alignment,
2265 // we can either pass an alignment to this method or verify alignment
2266 // in one of the methods further up the call chain. See bug 5044738.
2267 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2268
2269 // Repeatedly allocate blocks until the block is allocated at the
2270 // right spot.
2271
2272 // Bsd mmap allows caller to pass an address as hint; give it a try first,
2273 // if kernel honors the hint then we can return immediately.
2274 char * addr = anon_mmap(requested_addr, bytes, false);
2275 if (addr == requested_addr) {
2276 return requested_addr;
2277 }
2278
2279 if (addr != NULL) {
2280 // mmap() is successful but it fails to reserve at the requested address
2281 anon_munmap(addr, bytes);
2282 }
2283
2284 int i;
2285 for (i = 0; i < max_tries; ++i) {
2286 base[i] = reserve_memory(bytes);
2287
2288 if (base[i] != NULL) {
2289 // Is this the block we wanted?
2290 if (base[i] == requested_addr) {
2291 size[i] = bytes;
2292 break;
2293 }
2294
2295 // Does this overlap the block we wanted? Give back the overlapped
2296 // parts and try again.
2297
2298 size_t top_overlap = requested_addr + (bytes + gap) - base[i];
2299 if (top_overlap >= 0 && top_overlap < bytes) {
2300 unmap_memory(base[i], top_overlap);
2301 base[i] += top_overlap;
2302 size[i] = bytes - top_overlap;
2303 } else {
2304 size_t bottom_overlap = base[i] + bytes - requested_addr;
2305 if (bottom_overlap >= 0 && bottom_overlap < bytes) {
2306 unmap_memory(requested_addr, bottom_overlap);
2307 size[i] = bytes - bottom_overlap;
2308 } else {
2309 size[i] = bytes;
2310 }
2311 }
2312 }
2313 }
2314
2315 // Give back the unused reserved pieces.
2316
2317 for (int j = 0; j < i; ++j) {
2318 if (base[j] != NULL) {
2319 unmap_memory(base[j], size[j]);
2320 }
2321 }
2322
2323 if (i < max_tries) {
2324 return requested_addr;
2325 } else {
2326 return NULL;
2327 }
2328 }
2329
2330 size_t os::read(int fd, void *buf, unsigned int nBytes) {
2331 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes));
2332 }
2333
2334 size_t os::read_at(int fd, void *buf, unsigned int nBytes, jlong offset) {
2335 RESTARTABLE_RETURN_INT(::pread(fd, buf, nBytes, offset));
2336 }
2337
2338 void os::naked_short_sleep(jlong ms) {
2339 struct timespec req;
2340
2341 assert(ms < 1000, "Un-interruptable sleep, short time use only");
2342 req.tv_sec = 0;
2343 if (ms > 0) {
2344 req.tv_nsec = (ms % 1000) * 1000000;
2345 } else {
2346 req.tv_nsec = 1;
2347 }
2348
2349 nanosleep(&req, NULL);
2350
2351 return;
2352 }
2353
2354 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2355 void os::infinite_sleep() {
2356 while (true) { // sleep forever ...
2357 ::sleep(100); // ... 100 seconds at a time
2358 }
2359 }
2360
2361 // Used to convert frequent JVM_Yield() to nops
2362 bool os::dont_yield() {
2363 return DontYieldALot;
2364 }
2365
2366 void os::naked_yield() {
2367 sched_yield();
2368 }
2369
2370 ////////////////////////////////////////////////////////////////////////////////
2371 // thread priority support
2372
2373 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2374 // only supports dynamic priority, static priority must be zero. For real-time
2375 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
2376 // However, for large multi-threaded applications, SCHED_RR is not only slower
2377 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2378 // of 5 runs - Sep 2005).
2379 //
2380 // The following code actually changes the niceness of kernel-thread/LWP. It
2381 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
2382 // not the entire user process, and user level threads are 1:1 mapped to kernel
2383 // threads. It has always been the case, but could change in the future. For
2384 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2385 // It is only used when ThreadPriorityPolicy=1 and may require system level permission
2386 // (e.g., root privilege or CAP_SYS_NICE capability).
2387
2388 #if !defined(__APPLE__)
2389 int os::java_to_os_priority[CriticalPriority + 1] = {
2390 19, // 0 Entry should never be used
2391
2392 0, // 1 MinPriority
2393 3, // 2
2394 6, // 3
2395
2396 10, // 4
2397 15, // 5 NormPriority
2398 18, // 6
2399
2400 21, // 7
2401 25, // 8
2402 28, // 9 NearMaxPriority
2403
2404 31, // 10 MaxPriority
2405
2406 31 // 11 CriticalPriority
2407 };
2408 #else
2409 // Using Mach high-level priority assignments
2410 int os::java_to_os_priority[CriticalPriority + 1] = {
2411 0, // 0 Entry should never be used (MINPRI_USER)
2412
2413 27, // 1 MinPriority
2414 28, // 2
2415 29, // 3
2416
2417 30, // 4
2418 31, // 5 NormPriority (BASEPRI_DEFAULT)
2419 32, // 6
2420
2421 33, // 7
2422 34, // 8
2423 35, // 9 NearMaxPriority
2424
2425 36, // 10 MaxPriority
2426
2427 36 // 11 CriticalPriority
2428 };
2429 #endif
2430
2431 static int prio_init() {
2432 if (ThreadPriorityPolicy == 1) {
2433 if (geteuid() != 0) {
2434 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
2435 warning("-XX:ThreadPriorityPolicy=1 may require system level permission, " \
2436 "e.g., being the root user. If the necessary permission is not " \
2437 "possessed, changes to priority will be silently ignored.");
2438 }
2439 }
2440 }
2441 if (UseCriticalJavaThreadPriority) {
2442 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2443 }
2444 return 0;
2445 }
2446
2447 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2448 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) return OS_OK;
2449
2450 #ifdef __OpenBSD__
2451 // OpenBSD pthread_setprio starves low priority threads
2452 return OS_OK;
2453 #elif defined(__FreeBSD__)
2454 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2455 return (ret == 0) ? OS_OK : OS_ERR;
2456 #elif defined(__APPLE__) || defined(__NetBSD__)
2457 struct sched_param sp;
2458 int policy;
2459
2460 if (pthread_getschedparam(thread->osthread()->pthread_id(), &policy, &sp) != 0) {
2461 return OS_ERR;
2462 }
2463
2464 sp.sched_priority = newpri;
2465 if (pthread_setschedparam(thread->osthread()->pthread_id(), policy, &sp) != 0) {
2466 return OS_ERR;
2467 }
2468
2469 return OS_OK;
2470 #else
2471 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2472 return (ret == 0) ? OS_OK : OS_ERR;
2473 #endif
2474 }
2475
2476 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2477 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) {
2478 *priority_ptr = java_to_os_priority[NormPriority];
2479 return OS_OK;
2480 }
2481
2482 errno = 0;
2483 #if defined(__OpenBSD__) || defined(__FreeBSD__)
2484 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2485 #elif defined(__APPLE__) || defined(__NetBSD__)
2486 int policy;
2487 struct sched_param sp;
2488
2489 int res = pthread_getschedparam(thread->osthread()->pthread_id(), &policy, &sp);
2490 if (res != 0) {
2491 *priority_ptr = -1;
2492 return OS_ERR;
2493 } else {
2494 *priority_ptr = sp.sched_priority;
2495 return OS_OK;
2496 }
2497 #else
2498 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2499 #endif
2500 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2501 }
2502
2503 // Hint to the underlying OS that a task switch would not be good.
2504 // Void return because it's a hint and can fail.
2505 void os::hint_no_preempt() {}
2506
2507 ////////////////////////////////////////////////////////////////////////////////
2508 // suspend/resume support
2509
2510 // The low-level signal-based suspend/resume support is a remnant from the
2511 // old VM-suspension that used to be for java-suspension, safepoints etc,
2512 // within hotspot. Currently used by JFR's OSThreadSampler
2513 //
2514 // The remaining code is greatly simplified from the more general suspension
2515 // code that used to be used.
2516 //
2517 // The protocol is quite simple:
2518 // - suspend:
2519 // - sends a signal to the target thread
2520 // - polls the suspend state of the osthread using a yield loop
2521 // - target thread signal handler (SR_handler) sets suspend state
2522 // and blocks in sigsuspend until continued
2523 // - resume:
2524 // - sets target osthread state to continue
2525 // - sends signal to end the sigsuspend loop in the SR_handler
2526 //
2527 // Note that the SR_lock plays no role in this suspend/resume protocol,
2528 // but is checked for NULL in SR_handler as a thread termination indicator.
2529 // The SR_lock is, however, used by JavaThread::java_suspend()/java_resume() APIs.
2530 //
2531 // Note that resume_clear_context() and suspend_save_context() are needed
2532 // by SR_handler(), so that fetch_frame_from_ucontext() works,
2533 // which in part is used by:
2534 // - Forte Analyzer: AsyncGetCallTrace()
2535 // - StackBanging: get_frame_at_stack_banging_point()
2536
2537 static void resume_clear_context(OSThread *osthread) {
2538 osthread->set_ucontext(NULL);
2539 osthread->set_siginfo(NULL);
2540 }
2541
2542 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2543 osthread->set_ucontext(context);
2544 osthread->set_siginfo(siginfo);
2545 }
2546
2547 // Handler function invoked when a thread's execution is suspended or
2548 // resumed. We have to be careful that only async-safe functions are
2549 // called here (Note: most pthread functions are not async safe and
2550 // should be avoided.)
2551 //
2552 // Note: sigwait() is a more natural fit than sigsuspend() from an
2553 // interface point of view, but sigwait() prevents the signal hander
2554 // from being run. libpthread would get very confused by not having
2555 // its signal handlers run and prevents sigwait()'s use with the
2556 // mutex granting granting signal.
2557 //
2558 // Currently only ever called on the VMThread or JavaThread
2559 //
2560 #ifdef __APPLE__
2561 static OSXSemaphore sr_semaphore;
2562 #else
2563 static PosixSemaphore sr_semaphore;
2564 #endif
2565
2566 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2567 // Save and restore errno to avoid confusing native code with EINTR
2568 // after sigsuspend.
2569 int old_errno = errno;
2570
2571 Thread* thread = Thread::current_or_null_safe();
2572 assert(thread != NULL, "Missing current thread in SR_handler");
2573
2574 // On some systems we have seen signal delivery get "stuck" until the signal
2575 // mask is changed as part of thread termination. Check that the current thread
2576 // has not already terminated (via SR_lock()) - else the following assertion
2577 // will fail because the thread is no longer a JavaThread as the ~JavaThread
2578 // destructor has completed.
2579
2580 if (thread->SR_lock() == NULL) {
2581 return;
2582 }
2583
2584 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
2585
2586 OSThread* osthread = thread->osthread();
2587
2588 os::SuspendResume::State current = osthread->sr.state();
2589 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
2590 suspend_save_context(osthread, siginfo, context);
2591
2592 // attempt to switch the state, we assume we had a SUSPEND_REQUEST
2593 os::SuspendResume::State state = osthread->sr.suspended();
2594 if (state == os::SuspendResume::SR_SUSPENDED) {
2595 sigset_t suspend_set; // signals for sigsuspend()
2596
2597 // get current set of blocked signals and unblock resume signal
2598 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2599 sigdelset(&suspend_set, SR_signum);
2600
2601 sr_semaphore.signal();
2602 // wait here until we are resumed
2603 while (1) {
2604 sigsuspend(&suspend_set);
2605
2606 os::SuspendResume::State result = osthread->sr.running();
2607 if (result == os::SuspendResume::SR_RUNNING) {
2608 sr_semaphore.signal();
2609 break;
2610 } else if (result != os::SuspendResume::SR_SUSPENDED) {
2611 ShouldNotReachHere();
2612 }
2613 }
2614
2615 } else if (state == os::SuspendResume::SR_RUNNING) {
2616 // request was cancelled, continue
2617 } else {
2618 ShouldNotReachHere();
2619 }
2620
2621 resume_clear_context(osthread);
2622 } else if (current == os::SuspendResume::SR_RUNNING) {
2623 // request was cancelled, continue
2624 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
2625 // ignore
2626 } else {
2627 // ignore
2628 }
2629
2630 errno = old_errno;
2631 }
2632
2633
2634 static int SR_initialize() {
2635 struct sigaction act;
2636 char *s;
2637 // Get signal number to use for suspend/resume
2638 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2639 int sig = ::strtol(s, 0, 10);
2640 if (sig > MAX2(SIGSEGV, SIGBUS) && // See 4355769.
2641 sig < NSIG) { // Must be legal signal and fit into sigflags[].
2642 SR_signum = sig;
2643 } else {
2644 warning("You set _JAVA_SR_SIGNUM=%d. It must be in range [%d, %d]. Using %d instead.",
2645 sig, MAX2(SIGSEGV, SIGBUS)+1, NSIG-1, SR_signum);
2646 }
2647 }
2648
2649 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2650 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2651
2652 sigemptyset(&SR_sigset);
2653 sigaddset(&SR_sigset, SR_signum);
2654
2655 // Set up signal handler for suspend/resume
2656 act.sa_flags = SA_RESTART|SA_SIGINFO;
2657 act.sa_handler = (void (*)(int)) SR_handler;
2658
2659 // SR_signum is blocked by default.
2660 // 4528190 - We also need to block pthread restart signal (32 on all
2661 // supported Bsd platforms). Note that BsdThreads need to block
2662 // this signal for all threads to work properly. So we don't have
2663 // to use hard-coded signal number when setting up the mask.
2664 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2665
2666 if (sigaction(SR_signum, &act, 0) == -1) {
2667 return -1;
2668 }
2669
2670 // Save signal flag
2671 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2672 return 0;
2673 }
2674
2675 static int sr_notify(OSThread* osthread) {
2676 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2677 assert_status(status == 0, status, "pthread_kill");
2678 return status;
2679 }
2680
2681 // "Randomly" selected value for how long we want to spin
2682 // before bailing out on suspending a thread, also how often
2683 // we send a signal to a thread we want to resume
2684 static const int RANDOMLY_LARGE_INTEGER = 1000000;
2685 static const int RANDOMLY_LARGE_INTEGER2 = 100;
2686
2687 // returns true on success and false on error - really an error is fatal
2688 // but this seems the normal response to library errors
2689 static bool do_suspend(OSThread* osthread) {
2690 assert(osthread->sr.is_running(), "thread should be running");
2691 assert(!sr_semaphore.trywait(), "semaphore has invalid state");
2692
2693 // mark as suspended and send signal
2694 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
2695 // failed to switch, state wasn't running?
2696 ShouldNotReachHere();
2697 return false;
2698 }
2699
2700 if (sr_notify(osthread) != 0) {
2701 ShouldNotReachHere();
2702 }
2703
2704 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
2705 while (true) {
2706 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2707 break;
2708 } else {
2709 // timeout
2710 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
2711 if (cancelled == os::SuspendResume::SR_RUNNING) {
2712 return false;
2713 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
2714 // make sure that we consume the signal on the semaphore as well
2715 sr_semaphore.wait();
2716 break;
2717 } else {
2718 ShouldNotReachHere();
2719 return false;
2720 }
2721 }
2722 }
2723
2724 guarantee(osthread->sr.is_suspended(), "Must be suspended");
2725 return true;
2726 }
2727
2728 static void do_resume(OSThread* osthread) {
2729 assert(osthread->sr.is_suspended(), "thread should be suspended");
2730 assert(!sr_semaphore.trywait(), "invalid semaphore state");
2731
2732 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
2733 // failed to switch to WAKEUP_REQUEST
2734 ShouldNotReachHere();
2735 return;
2736 }
2737
2738 while (true) {
2739 if (sr_notify(osthread) == 0) {
2740 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2741 if (osthread->sr.is_running()) {
2742 return;
2743 }
2744 }
2745 } else {
2746 ShouldNotReachHere();
2747 }
2748 }
2749
2750 guarantee(osthread->sr.is_running(), "Must be running!");
2751 }
2752
2753 ///////////////////////////////////////////////////////////////////////////////////
2754 // signal handling (except suspend/resume)
2755
2756 // This routine may be used by user applications as a "hook" to catch signals.
2757 // The user-defined signal handler must pass unrecognized signals to this
2758 // routine, and if it returns true (non-zero), then the signal handler must
2759 // return immediately. If the flag "abort_if_unrecognized" is true, then this
2760 // routine will never retun false (zero), but instead will execute a VM panic
2761 // routine kill the process.
2762 //
2763 // If this routine returns false, it is OK to call it again. This allows
2764 // the user-defined signal handler to perform checks either before or after
2765 // the VM performs its own checks. Naturally, the user code would be making
2766 // a serious error if it tried to handle an exception (such as a null check
2767 // or breakpoint) that the VM was generating for its own correct operation.
2768 //
2769 // This routine may recognize any of the following kinds of signals:
2770 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
2771 // It should be consulted by handlers for any of those signals.
2772 //
2773 // The caller of this routine must pass in the three arguments supplied
2774 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
2775 // field of the structure passed to sigaction(). This routine assumes that
2776 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
2777 //
2778 // Note that the VM will print warnings if it detects conflicting signal
2779 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
2780 //
2781 extern "C" JNIEXPORT int JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
2782 void* ucontext,
2783 int abort_if_unrecognized);
2784
2785 static void signalHandler(int sig, siginfo_t* info, void* uc) {
2786 assert(info != NULL && uc != NULL, "it must be old kernel");
2787 int orig_errno = errno; // Preserve errno value over signal handler.
2788 JVM_handle_bsd_signal(sig, info, uc, true);
2789 errno = orig_errno;
2790 }
2791
2792
2793 // This boolean allows users to forward their own non-matching signals
2794 // to JVM_handle_bsd_signal, harmlessly.
2795 bool os::Bsd::signal_handlers_are_installed = false;
2796
2797 // For signal-chaining
2798 bool os::Bsd::libjsig_is_loaded = false;
2799 typedef struct sigaction *(*get_signal_t)(int);
2800 get_signal_t os::Bsd::get_signal_action = NULL;
2801
2802 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
2803 struct sigaction *actp = NULL;
2804
2805 if (libjsig_is_loaded) {
2806 // Retrieve the old signal handler from libjsig
2807 actp = (*get_signal_action)(sig);
2808 }
2809 if (actp == NULL) {
2810 // Retrieve the preinstalled signal handler from jvm
2811 actp = os::Posix::get_preinstalled_handler(sig);
2812 }
2813
2814 return actp;
2815 }
2816
2817 static bool call_chained_handler(struct sigaction *actp, int sig,
2818 siginfo_t *siginfo, void *context) {
2819 // Call the old signal handler
2820 if (actp->sa_handler == SIG_DFL) {
2821 // It's more reasonable to let jvm treat it as an unexpected exception
2822 // instead of taking the default action.
2823 return false;
2824 } else if (actp->sa_handler != SIG_IGN) {
2825 if ((actp->sa_flags & SA_NODEFER) == 0) {
2826 // automaticlly block the signal
2827 sigaddset(&(actp->sa_mask), sig);
2828 }
2829
2830 sa_handler_t hand;
2831 sa_sigaction_t sa;
2832 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
2833 // retrieve the chained handler
2834 if (siginfo_flag_set) {
2835 sa = actp->sa_sigaction;
2836 } else {
2837 hand = actp->sa_handler;
2838 }
2839
2840 if ((actp->sa_flags & SA_RESETHAND) != 0) {
2841 actp->sa_handler = SIG_DFL;
2842 }
2843
2844 // try to honor the signal mask
2845 sigset_t oset;
2846 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
2847
2848 // call into the chained handler
2849 if (siginfo_flag_set) {
2850 (*sa)(sig, siginfo, context);
2851 } else {
2852 (*hand)(sig);
2853 }
2854
2855 // restore the signal mask
2856 pthread_sigmask(SIG_SETMASK, &oset, 0);
2857 }
2858 // Tell jvm's signal handler the signal is taken care of.
2859 return true;
2860 }
2861
2862 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
2863 bool chained = false;
2864 // signal-chaining
2865 if (UseSignalChaining) {
2866 struct sigaction *actp = get_chained_signal_action(sig);
2867 if (actp != NULL) {
2868 chained = call_chained_handler(actp, sig, siginfo, context);
2869 }
2870 }
2871 return chained;
2872 }
2873
2874 // for diagnostic
2875 int sigflags[NSIG];
2876
2877 int os::Bsd::get_our_sigflags(int sig) {
2878 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
2879 return sigflags[sig];
2880 }
2881
2882 void os::Bsd::set_our_sigflags(int sig, int flags) {
2883 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
2884 if (sig > 0 && sig < NSIG) {
2885 sigflags[sig] = flags;
2886 }
2887 }
2888
2889 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
2890 // Check for overwrite.
2891 struct sigaction oldAct;
2892 sigaction(sig, (struct sigaction*)NULL, &oldAct);
2893
2894 void* oldhand = oldAct.sa_sigaction
2895 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
2896 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
2897 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
2898 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
2899 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
2900 if (AllowUserSignalHandlers || !set_installed) {
2901 // Do not overwrite; user takes responsibility to forward to us.
2902 return;
2903 } else if (UseSignalChaining) {
2904 // save the old handler in jvm
2905 os::Posix::save_preinstalled_handler(sig, oldAct);
2906 // libjsig also interposes the sigaction() call below and saves the
2907 // old sigaction on it own.
2908 } else {
2909 fatal("Encountered unexpected pre-existing sigaction handler "
2910 "%#lx for signal %d.", (long)oldhand, sig);
2911 }
2912 }
2913
2914 struct sigaction sigAct;
2915 sigfillset(&(sigAct.sa_mask));
2916 sigAct.sa_handler = SIG_DFL;
2917 if (!set_installed) {
2918 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
2919 } else {
2920 sigAct.sa_sigaction = signalHandler;
2921 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
2922 }
2923 #ifdef __APPLE__
2924 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV
2925 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages"
2926 // if the signal handler declares it will handle it on alternate stack.
2927 // Notice we only declare we will handle it on alt stack, but we are not
2928 // actually going to use real alt stack - this is just a workaround.
2929 // Please see ux_exception.c, method catch_mach_exception_raise for details
2930 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c
2931 if (sig == SIGSEGV) {
2932 sigAct.sa_flags |= SA_ONSTACK;
2933 }
2934 #endif
2935
2936 // Save flags, which are set by ours
2937 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
2938 sigflags[sig] = sigAct.sa_flags;
2939
2940 int ret = sigaction(sig, &sigAct, &oldAct);
2941 assert(ret == 0, "check");
2942
2943 void* oldhand2 = oldAct.sa_sigaction
2944 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
2945 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
2946 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
2947 }
2948
2949 // install signal handlers for signals that HotSpot needs to
2950 // handle in order to support Java-level exception handling.
2951
2952 void os::Bsd::install_signal_handlers() {
2953 if (!signal_handlers_are_installed) {
2954 signal_handlers_are_installed = true;
2955
2956 // signal-chaining
2957 typedef void (*signal_setting_t)();
2958 signal_setting_t begin_signal_setting = NULL;
2959 signal_setting_t end_signal_setting = NULL;
2960 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
2961 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
2962 if (begin_signal_setting != NULL) {
2963 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
2964 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
2965 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
2966 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
2967 libjsig_is_loaded = true;
2968 assert(UseSignalChaining, "should enable signal-chaining");
2969 }
2970 if (libjsig_is_loaded) {
2971 // Tell libjsig jvm is setting signal handlers
2972 (*begin_signal_setting)();
2973 }
2974
2975 set_signal_handler(SIGSEGV, true);
2976 set_signal_handler(SIGPIPE, true);
2977 set_signal_handler(SIGBUS, true);
2978 set_signal_handler(SIGILL, true);
2979 set_signal_handler(SIGFPE, true);
2980 set_signal_handler(SIGXFSZ, true);
2981
2982 #if defined(__APPLE__)
2983 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
2984 // signals caught and handled by the JVM. To work around this, we reset the mach task
2985 // signal handler that's placed on our process by CrashReporter. This disables
2986 // CrashReporter-based reporting.
2987 //
2988 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
2989 // on caught fatal signals.
2990 //
2991 // Additionally, gdb installs both standard BSD signal handlers, and mach exception
2992 // handlers. By replacing the existing task exception handler, we disable gdb's mach
2993 // exception handling, while leaving the standard BSD signal handlers functional.
2994 kern_return_t kr;
2995 kr = task_set_exception_ports(mach_task_self(),
2996 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
2997 MACH_PORT_NULL,
2998 EXCEPTION_STATE_IDENTITY,
2999 MACHINE_THREAD_STATE);
3000
3001 assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
3002 #endif
3003
3004 if (libjsig_is_loaded) {
3005 // Tell libjsig jvm finishes setting signal handlers
3006 (*end_signal_setting)();
3007 }
3008
3009 // We don't activate signal checker if libjsig is in place, we trust ourselves
3010 // and if UserSignalHandler is installed all bets are off
3011 if (CheckJNICalls) {
3012 if (libjsig_is_loaded) {
3013 if (PrintJNIResolving) {
3014 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
3015 }
3016 check_signals = false;
3017 }
3018 if (AllowUserSignalHandlers) {
3019 if (PrintJNIResolving) {
3020 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
3021 }
3022 check_signals = false;
3023 }
3024 }
3025 }
3026 }
3027
3028
3029 /////
3030 // glibc on Bsd platform uses non-documented flag
3031 // to indicate, that some special sort of signal
3032 // trampoline is used.
3033 // We will never set this flag, and we should
3034 // ignore this flag in our diagnostic
3035 #ifdef SIGNIFICANT_SIGNAL_MASK
3036 #undef SIGNIFICANT_SIGNAL_MASK
3037 #endif
3038 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
3039
3040 static const char* get_signal_handler_name(address handler,
3041 char* buf, int buflen) {
3042 int offset;
3043 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
3044 if (found) {
3045 // skip directory names
3046 const char *p1, *p2;
3047 p1 = buf;
3048 size_t len = strlen(os::file_separator());
3049 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
3050 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
3051 } else {
3052 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
3053 }
3054 return buf;
3055 }
3056
3057 static void print_signal_handler(outputStream* st, int sig,
3058 char* buf, size_t buflen) {
3059 struct sigaction sa;
3060
3061 sigaction(sig, NULL, &sa);
3062
3063 // See comment for SIGNIFICANT_SIGNAL_MASK define
3064 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3065
3066 st->print("%s: ", os::exception_name(sig, buf, buflen));
3067
3068 address handler = (sa.sa_flags & SA_SIGINFO)
3069 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
3070 : CAST_FROM_FN_PTR(address, sa.sa_handler);
3071
3072 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
3073 st->print("SIG_DFL");
3074 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
3075 st->print("SIG_IGN");
3076 } else {
3077 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
3078 }
3079
3080 st->print(", sa_mask[0]=");
3081 os::Posix::print_signal_set_short(st, &sa.sa_mask);
3082
3083 address rh = VMError::get_resetted_sighandler(sig);
3084 // May be, handler was resetted by VMError?
3085 if (rh != NULL) {
3086 handler = rh;
3087 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
3088 }
3089
3090 st->print(", sa_flags=");
3091 os::Posix::print_sa_flags(st, sa.sa_flags);
3092
3093 // Check: is it our handler?
3094 if (handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
3095 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
3096 // It is our signal handler
3097 // check for flags, reset system-used one!
3098 if ((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3099 st->print(
3100 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
3101 os::Bsd::get_our_sigflags(sig));
3102 }
3103 }
3104 st->cr();
3105 }
3106
3107
3108 #define DO_SIGNAL_CHECK(sig) \
3109 do { \
3110 if (!sigismember(&check_signal_done, sig)) { \
3111 os::Bsd::check_signal_handler(sig); \
3112 } \
3113 } while (0)
3114
3115 // This method is a periodic task to check for misbehaving JNI applications
3116 // under CheckJNI, we can add any periodic checks here
3117
3118 void os::run_periodic_checks() {
3119
3120 if (check_signals == false) return;
3121
3122 // SEGV and BUS if overridden could potentially prevent
3123 // generation of hs*.log in the event of a crash, debugging
3124 // such a case can be very challenging, so we absolutely
3125 // check the following for a good measure:
3126 DO_SIGNAL_CHECK(SIGSEGV);
3127 DO_SIGNAL_CHECK(SIGILL);
3128 DO_SIGNAL_CHECK(SIGFPE);
3129 DO_SIGNAL_CHECK(SIGBUS);
3130 DO_SIGNAL_CHECK(SIGPIPE);
3131 DO_SIGNAL_CHECK(SIGXFSZ);
3132
3133
3134 // ReduceSignalUsage allows the user to override these handlers
3135 // see comments at the very top and jvm_md.h
3136 if (!ReduceSignalUsage) {
3137 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
3138 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
3139 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
3140 DO_SIGNAL_CHECK(BREAK_SIGNAL);
3141 }
3142
3143 DO_SIGNAL_CHECK(SR_signum);
3144 }
3145
3146 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
3147
3148 static os_sigaction_t os_sigaction = NULL;
3149
3150 void os::Bsd::check_signal_handler(int sig) {
3151 char buf[O_BUFLEN];
3152 address jvmHandler = NULL;
3153
3154
3155 struct sigaction act;
3156 if (os_sigaction == NULL) {
3157 // only trust the default sigaction, in case it has been interposed
3158 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
3159 if (os_sigaction == NULL) return;
3160 }
3161
3162 os_sigaction(sig, (struct sigaction*)NULL, &act);
3163
3164
3165 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3166
3167 address thisHandler = (act.sa_flags & SA_SIGINFO)
3168 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3169 : CAST_FROM_FN_PTR(address, act.sa_handler);
3170
3171
3172 switch (sig) {
3173 case SIGSEGV:
3174 case SIGBUS:
3175 case SIGFPE:
3176 case SIGPIPE:
3177 case SIGILL:
3178 case SIGXFSZ:
3179 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
3180 break;
3181
3182 case SHUTDOWN1_SIGNAL:
3183 case SHUTDOWN2_SIGNAL:
3184 case SHUTDOWN3_SIGNAL:
3185 case BREAK_SIGNAL:
3186 jvmHandler = (address)user_handler();
3187 break;
3188
3189 default:
3190 if (sig == SR_signum) {
3191 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3192 } else {
3193 return;
3194 }
3195 break;
3196 }
3197
3198 if (thisHandler != jvmHandler) {
3199 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3200 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3201 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3202 // No need to check this sig any longer
3203 sigaddset(&check_signal_done, sig);
3204 // Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN
3205 if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) {
3206 tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell",
3207 exception_name(sig, buf, O_BUFLEN));
3208 }
3209 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3210 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3211 tty->print("expected:");
3212 os::Posix::print_sa_flags(tty, os::Bsd::get_our_sigflags(sig));
3213 tty->cr();
3214 tty->print(" found:");
3215 os::Posix::print_sa_flags(tty, act.sa_flags);
3216 tty->cr();
3217 // No need to check this sig any longer
3218 sigaddset(&check_signal_done, sig);
3219 }
3220
3221 // Dump all the signal
3222 if (sigismember(&check_signal_done, sig)) {
3223 print_signal_handlers(tty, buf, O_BUFLEN);
3224 }
3225 }
3226
3227 extern void report_error(char* file_name, int line_no, char* title,
3228 char* format, ...);
3229
3230 // this is called _before_ the most of global arguments have been parsed
3231 void os::init(void) {
3232 char dummy; // used to get a guess on initial stack address
3233
3234 // With BsdThreads the JavaMain thread pid (primordial thread)
3235 // is different than the pid of the java launcher thread.
3236 // So, on Bsd, the launcher thread pid is passed to the VM
3237 // via the sun.java.launcher.pid property.
3238 // Use this property instead of getpid() if it was correctly passed.
3239 // See bug 6351349.
3240 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid();
3241
3242 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid();
3243
3244 clock_tics_per_sec = CLK_TCK;
3245
3246 init_random(1234567);
3247
3248 Bsd::set_page_size(getpagesize());
3249 if (Bsd::page_size() == -1) {
3250 fatal("os_bsd.cpp: os::init: sysconf failed (%s)", os::strerror(errno));
3251 }
3252 init_page_sizes((size_t) Bsd::page_size());
3253
3254 Bsd::initialize_system_info();
3255
3256 // _main_thread points to the thread that created/loaded the JVM.
3257 Bsd::_main_thread = pthread_self();
3258
3259 Bsd::clock_init();
3260 initial_time_count = javaTimeNanos();
3261
3262 #ifdef __APPLE__
3263 // XXXDARWIN
3264 // Work around the unaligned VM callbacks in hotspot's
3265 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on
3266 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces
3267 // alignment when doing symbol lookup. To work around this, we force early
3268 // binding of all symbols now, thus binding when alignment is known-good.
3269 _dyld_bind_fully_image_containing_address((const void *) &os::init);
3270 #endif
3271
3272 os::Posix::init();
3273 }
3274
3275 // To install functions for atexit system call
3276 extern "C" {
3277 static void perfMemory_exit_helper() {
3278 perfMemory_exit();
3279 }
3280 }
3281
3282 // this is called _after_ the global arguments have been parsed
3283 jint os::init_2(void) {
3284
3285 os::Posix::init_2();
3286
3287 // initialize suspend/resume support - must do this before signal_sets_init()
3288 if (SR_initialize() != 0) {
3289 perror("SR_initialize failed");
3290 return JNI_ERR;
3291 }
3292
3293 Bsd::signal_sets_init();
3294 Bsd::install_signal_handlers();
3295 // Initialize data for jdk.internal.misc.Signal
3296 if (!ReduceSignalUsage) {
3297 jdk_misc_signal_init();
3298 }
3299
3300 // Check and sets minimum stack sizes against command line options
3301 if (Posix::set_minimum_stack_sizes() == JNI_ERR) {
3302 return JNI_ERR;
3303 }
3304
3305 if (MaxFDLimit) {
3306 // set the number of file descriptors to max. print out error
3307 // if getrlimit/setrlimit fails but continue regardless.
3308 struct rlimit nbr_files;
3309 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3310 if (status != 0) {
3311 log_info(os)("os::init_2 getrlimit failed: %s", os::strerror(errno));
3312 } else {
3313 nbr_files.rlim_cur = nbr_files.rlim_max;
3314
3315 #ifdef __APPLE__
3316 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3317 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3318 // be used instead
3319 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3320 #endif
3321
3322 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3323 if (status != 0) {
3324 log_info(os)("os::init_2 setrlimit failed: %s", os::strerror(errno));
3325 }
3326 }
3327 }
3328
3329 // at-exit methods are called in the reverse order of their registration.
3330 // atexit functions are called on return from main or as a result of a
3331 // call to exit(3C). There can be only 32 of these functions registered
3332 // and atexit() does not set errno.
3333
3334 if (PerfAllowAtExitRegistration) {
3335 // only register atexit functions if PerfAllowAtExitRegistration is set.
3336 // atexit functions can be delayed until process exit time, which
3337 // can be problematic for embedded VM situations. Embedded VMs should
3338 // call DestroyJavaVM() to assure that VM resources are released.
3339
3340 // note: perfMemory_exit_helper atexit function may be removed in
3341 // the future if the appropriate cleanup code can be added to the
3342 // VM_Exit VMOperation's doit method.
3343 if (atexit(perfMemory_exit_helper) != 0) {
3344 warning("os::init_2 atexit(perfMemory_exit_helper) failed");
3345 }
3346 }
3347
3348 // initialize thread priority policy
3349 prio_init();
3350
3351 #ifdef __APPLE__
3352 // dynamically link to objective c gc registration
3353 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3354 if (handleLibObjc != NULL) {
3355 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3356 }
3357 #endif
3358
3359 return JNI_OK;
3360 }
3361
3362 // Mark the polling page as unreadable
3363 void os::make_polling_page_unreadable(void) {
3364 if (!guard_memory((char*)_polling_page, Bsd::page_size())) {
3365 fatal("Could not disable polling page");
3366 }
3367 }
3368
3369 // Mark the polling page as readable
3370 void os::make_polling_page_readable(void) {
3371 if (!bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
3372 fatal("Could not enable polling page");
3373 }
3374 }
3375
3376 int os::active_processor_count() {
3377 // User has overridden the number of active processors
3378 if (ActiveProcessorCount > 0) {
3379 log_trace(os)("active_processor_count: "
3380 "active processor count set by user : %d",
3381 ActiveProcessorCount);
3382 return ActiveProcessorCount;
3383 }
3384
3385 return _processor_count;
3386 }
3387
3388 void os::set_native_thread_name(const char *name) {
3389 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3390 // This is only supported in Snow Leopard and beyond
3391 if (name != NULL) {
3392 // Add a "Java: " prefix to the name
3393 char buf[MAXTHREADNAMESIZE];
3394 snprintf(buf, sizeof(buf), "Java: %s", name);
3395 pthread_setname_np(buf);
3396 }
3397 #endif
3398 }
3399
3400 bool os::distribute_processes(uint length, uint* distribution) {
3401 // Not yet implemented.
3402 return false;
3403 }
3404
3405 bool os::bind_to_processor(uint processor_id) {
3406 // Not yet implemented.
3407 return false;
3408 }
3409
3410 void os::SuspendedThreadTask::internal_do_task() {
3411 if (do_suspend(_thread->osthread())) {
3412 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
3413 do_task(context);
3414 do_resume(_thread->osthread());
3415 }
3416 }
3417
3418 ////////////////////////////////////////////////////////////////////////////////
3419 // debug support
3420
3421 bool os::find(address addr, outputStream* st) {
3422 Dl_info dlinfo;
3423 memset(&dlinfo, 0, sizeof(dlinfo));
3424 if (dladdr(addr, &dlinfo) != 0) {
3425 st->print(INTPTR_FORMAT ": ", (intptr_t)addr);
3426 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) {
3427 st->print("%s+%#x", dlinfo.dli_sname,
3428 (uint)((uintptr_t)addr - (uintptr_t)dlinfo.dli_saddr));
3429 } else if (dlinfo.dli_fbase != NULL) {
3430 st->print("<offset %#x>", (uint)((uintptr_t)addr - (uintptr_t)dlinfo.dli_fbase));
3431 } else {
3432 st->print("<absolute address>");
3433 }
3434 if (dlinfo.dli_fname != NULL) {
3435 st->print(" in %s", dlinfo.dli_fname);
3436 }
3437 if (dlinfo.dli_fbase != NULL) {
3438 st->print(" at " INTPTR_FORMAT, (intptr_t)dlinfo.dli_fbase);
3439 }
3440 st->cr();
3441
3442 if (Verbose) {
3443 // decode some bytes around the PC
3444 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
3445 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size());
3446 address lowest = (address) dlinfo.dli_sname;
3447 if (!lowest) lowest = (address) dlinfo.dli_fbase;
3448 if (begin < lowest) begin = lowest;
3449 Dl_info dlinfo2;
3450 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr
3451 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) {
3452 end = (address) dlinfo2.dli_saddr;
3453 }
3454 Disassembler::decode(begin, end, st);
3455 }
3456 return true;
3457 }
3458 return false;
3459 }
3460
3461 ////////////////////////////////////////////////////////////////////////////////
3462 // misc
3463
3464 // This does not do anything on Bsd. This is basically a hook for being
3465 // able to use structured exception handling (thread-local exception filters)
3466 // on, e.g., Win32.
3467 void os::os_exception_wrapper(java_call_t f, JavaValue* value,
3468 const methodHandle& method, JavaCallArguments* args,
3469 Thread* thread) {
3470 f(value, method, args, thread);
3471 }
3472
3473 void os::print_statistics() {
3474 }
3475
3476 bool os::message_box(const char* title, const char* message) {
3477 int i;
3478 fdStream err(defaultStream::error_fd());
3479 for (i = 0; i < 78; i++) err.print_raw("=");
3480 err.cr();
3481 err.print_raw_cr(title);
3482 for (i = 0; i < 78; i++) err.print_raw("-");
3483 err.cr();
3484 err.print_raw_cr(message);
3485 for (i = 0; i < 78; i++) err.print_raw("=");
3486 err.cr();
3487
3488 char buf[16];
3489 // Prevent process from exiting upon "read error" without consuming all CPU
3490 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3491
3492 return buf[0] == 'y' || buf[0] == 'Y';
3493 }
3494
3495 static inline struct timespec get_mtime(const char* filename) {
3496 struct stat st;
3497 int ret = os::stat(filename, &st);
3498 assert(ret == 0, "failed to stat() file '%s': %s", filename, strerror(errno));
3499 #ifdef __APPLE__
3500 return st.st_mtimespec;
3501 #else
3502 return st.st_mtim;
3503 #endif
3504 }
3505
3506 int os::compare_file_modified_times(const char* file1, const char* file2) {
3507 struct timespec filetime1 = get_mtime(file1);
3508 struct timespec filetime2 = get_mtime(file2);
3509 int diff = filetime1.tv_sec - filetime2.tv_sec;
3510 if (diff == 0) {
3511 return filetime1.tv_nsec - filetime2.tv_nsec;
3512 }
3513 return diff;
3514 }
3515
3516 // Is a (classpath) directory empty?
3517 bool os::dir_is_empty(const char* path) {
3518 DIR *dir = NULL;
3519 struct dirent *ptr;
3520
3521 dir = opendir(path);
3522 if (dir == NULL) return true;
3523
3524 // Scan the directory
3525 bool result = true;
3526 while (result && (ptr = readdir(dir)) != NULL) {
3527 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3528 result = false;
3529 }
3530 }
3531 closedir(dir);
3532 return result;
3533 }
3534
3535 // This code originates from JDK's sysOpen and open64_w
3536 // from src/solaris/hpi/src/system_md.c
3537
3538 int os::open(const char *path, int oflag, int mode) {
3539 if (strlen(path) > MAX_PATH - 1) {
3540 errno = ENAMETOOLONG;
3541 return -1;
3542 }
3543 int fd;
3544
3545 fd = ::open(path, oflag, mode);
3546 if (fd == -1) return -1;
3547
3548 // If the open succeeded, the file might still be a directory
3549 {
3550 struct stat buf;
3551 int ret = ::fstat(fd, &buf);
3552 int st_mode = buf.st_mode;
3553
3554 if (ret != -1) {
3555 if ((st_mode & S_IFMT) == S_IFDIR) {
3556 errno = EISDIR;
3557 ::close(fd);
3558 return -1;
3559 }
3560 } else {
3561 ::close(fd);
3562 return -1;
3563 }
3564 }
3565
3566 // All file descriptors that are opened in the JVM and not
3567 // specifically destined for a subprocess should have the
3568 // close-on-exec flag set. If we don't set it, then careless 3rd
3569 // party native code might fork and exec without closing all
3570 // appropriate file descriptors (e.g. as we do in closeDescriptors in
3571 // UNIXProcess.c), and this in turn might:
3572 //
3573 // - cause end-of-file to fail to be detected on some file
3574 // descriptors, resulting in mysterious hangs, or
3575 //
3576 // - might cause an fopen in the subprocess to fail on a system
3577 // suffering from bug 1085341.
3578 //
3579 // (Yes, the default setting of the close-on-exec flag is a Unix
3580 // design flaw)
3581 //
3582 // See:
3583 // 1085341: 32-bit stdio routines should support file descriptors >255
3584 // 4843136: (process) pipe file descriptor from Runtime.exec not being closed
3585 // 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
3586 //
3587 #ifdef FD_CLOEXEC
3588 {
3589 int flags = ::fcntl(fd, F_GETFD);
3590 if (flags != -1) {
3591 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
3592 }
3593 }
3594 #endif
3595
3596 return fd;
3597 }
3598
3599
3600 // create binary file, rewriting existing file if required
3601 int os::create_binary_file(const char* path, bool rewrite_existing) {
3602 int oflags = O_WRONLY | O_CREAT;
3603 if (!rewrite_existing) {
3604 oflags |= O_EXCL;
3605 }
3606 return ::open(path, oflags, S_IREAD | S_IWRITE);
3607 }
3608
3609 // return current position of file pointer
3610 jlong os::current_file_offset(int fd) {
3611 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
3612 }
3613
3614 // move file pointer to the specified offset
3615 jlong os::seek_to_file_offset(int fd, jlong offset) {
3616 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
3617 }
3618
3619 // This code originates from JDK's sysAvailable
3620 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
3621
3622 int os::available(int fd, jlong *bytes) {
3623 jlong cur, end;
3624 int mode;
3625 struct stat buf;
3626
3627 if (::fstat(fd, &buf) >= 0) {
3628 mode = buf.st_mode;
3629 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
3630 int n;
3631 if (::ioctl(fd, FIONREAD, &n) >= 0) {
3632 *bytes = n;
3633 return 1;
3634 }
3635 }
3636 }
3637 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
3638 return 0;
3639 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
3640 return 0;
3641 } else if (::lseek(fd, cur, SEEK_SET) == -1) {
3642 return 0;
3643 }
3644 *bytes = end - cur;
3645 return 1;
3646 }
3647
3648 // Map a block of memory.
3649 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
3650 char *addr, size_t bytes, bool read_only,
3651 bool allow_exec) {
3652 int prot;
3653 int flags;
3654
3655 if (read_only) {
3656 prot = PROT_READ;
3657 flags = MAP_SHARED;
3658 } else {
3659 prot = PROT_READ | PROT_WRITE;
3660 flags = MAP_PRIVATE;
3661 }
3662
3663 if (allow_exec) {
3664 prot |= PROT_EXEC;
3665 }
3666
3667 if (addr != NULL) {
3668 flags |= MAP_FIXED;
3669 }
3670
3671 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
3672 fd, file_offset);
3673 if (mapped_address == MAP_FAILED) {
3674 return NULL;
3675 }
3676 return mapped_address;
3677 }
3678
3679
3680 // Remap a block of memory.
3681 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
3682 char *addr, size_t bytes, bool read_only,
3683 bool allow_exec) {
3684 // same as map_memory() on this OS
3685 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
3686 allow_exec);
3687 }
3688
3689
3690 // Unmap a block of memory.
3691 bool os::pd_unmap_memory(char* addr, size_t bytes) {
3692 return munmap(addr, bytes) == 0;
3693 }
3694
3695 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
3696 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
3697 // of a thread.
3698 //
3699 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
3700 // the fast estimate available on the platform.
3701
3702 jlong os::current_thread_cpu_time() {
3703 #ifdef __APPLE__
3704 return os::thread_cpu_time(Thread::current(), true /* user + sys */);
3705 #else
3706 Unimplemented();
3707 return 0;
3708 #endif
3709 }
3710
3711 jlong os::thread_cpu_time(Thread* thread) {
3712 #ifdef __APPLE__
3713 return os::thread_cpu_time(thread, true /* user + sys */);
3714 #else
3715 Unimplemented();
3716 return 0;
3717 #endif
3718 }
3719
3720 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
3721 #ifdef __APPLE__
3722 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
3723 #else
3724 Unimplemented();
3725 return 0;
3726 #endif
3727 }
3728
3729 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
3730 #ifdef __APPLE__
3731 struct thread_basic_info tinfo;
3732 mach_msg_type_number_t tcount = THREAD_INFO_MAX;
3733 kern_return_t kr;
3734 thread_t mach_thread;
3735
3736 mach_thread = thread->osthread()->thread_id();
3737 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
3738 if (kr != KERN_SUCCESS) {
3739 return -1;
3740 }
3741
3742 if (user_sys_cpu_time) {
3743 jlong nanos;
3744 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
3745 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
3746 return nanos;
3747 } else {
3748 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
3749 }
3750 #else
3751 Unimplemented();
3752 return 0;
3753 #endif
3754 }
3755
3756
3757 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
3758 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
3759 info_ptr->may_skip_backward = false; // elapsed time not wall time
3760 info_ptr->may_skip_forward = false; // elapsed time not wall time
3761 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
3762 }
3763
3764 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
3765 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
3766 info_ptr->may_skip_backward = false; // elapsed time not wall time
3767 info_ptr->may_skip_forward = false; // elapsed time not wall time
3768 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
3769 }
3770
3771 bool os::is_thread_cpu_time_supported() {
3772 #ifdef __APPLE__
3773 return true;
3774 #else
3775 return false;
3776 #endif
3777 }
3778
3779 // System loadavg support. Returns -1 if load average cannot be obtained.
3780 // Bsd doesn't yet have a (official) notion of processor sets,
3781 // so just return the system wide load average.
3782 int os::loadavg(double loadavg[], int nelem) {
3783 return ::getloadavg(loadavg, nelem);
3784 }
3785
3786 void os::pause() {
3787 char filename[MAX_PATH];
3788 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
3789 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
3790 } else {
3791 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
3792 }
3793
3794 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
3795 if (fd != -1) {
3796 struct stat buf;
3797 ::close(fd);
3798 while (::stat(filename, &buf) == 0) {
3799 (void)::poll(NULL, 0, 100);
3800 }
3801 } else {
3802 jio_fprintf(stderr,
3803 "Could not open pause file '%s', continuing immediately.\n", filename);
3804 }
3805 }
3806
3807 // Darwin has no "environ" in a dynamic library.
3808 #ifdef __APPLE__
3809 #include <crt_externs.h>
3810 #define environ (*_NSGetEnviron())
3811 #else
3812 extern char** environ;
3813 #endif
3814
3815 // Run the specified command in a separate process. Return its exit value,
3816 // or -1 on failure (e.g. can't fork a new process).
3817 // Unlike system(), this function can be called from signal handler. It
3818 // doesn't block SIGINT et al.
3819 int os::fork_and_exec(char* cmd, bool use_vfork_if_available) {
3820 const char * argv[4] = {"sh", "-c", cmd, NULL};
3821
3822 // fork() in BsdThreads/NPTL is not async-safe. It needs to run
3823 // pthread_atfork handlers and reset pthread library. All we need is a
3824 // separate process to execve. Make a direct syscall to fork process.
3825 // On IA64 there's no fork syscall, we have to use fork() and hope for
3826 // the best...
3827 pid_t pid = fork();
3828
3829 if (pid < 0) {
3830 // fork failed
3831 return -1;
3832
3833 } else if (pid == 0) {
3834 // child process
3835
3836 // execve() in BsdThreads will call pthread_kill_other_threads_np()
3837 // first to kill every thread on the thread list. Because this list is
3838 // not reset by fork() (see notes above), execve() will instead kill
3839 // every thread in the parent process. We know this is the only thread
3840 // in the new process, so make a system call directly.
3841 // IA64 should use normal execve() from glibc to match the glibc fork()
3842 // above.
3843 execve("/bin/sh", (char* const*)argv, environ);
3844
3845 // execve failed
3846 _exit(-1);
3847
3848 } else {
3849 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
3850 // care about the actual exit code, for now.
3851
3852 int status;
3853
3854 // Wait for the child process to exit. This returns immediately if
3855 // the child has already exited. */
3856 while (waitpid(pid, &status, 0) < 0) {
3857 switch (errno) {
3858 case ECHILD: return 0;
3859 case EINTR: break;
3860 default: return -1;
3861 }
3862 }
3863
3864 if (WIFEXITED(status)) {
3865 // The child exited normally; get its exit code.
3866 return WEXITSTATUS(status);
3867 } else if (WIFSIGNALED(status)) {
3868 // The child exited because of a signal
3869 // The best value to return is 0x80 + signal number,
3870 // because that is what all Unix shells do, and because
3871 // it allows callers to distinguish between process exit and
3872 // process death by signal.
3873 return 0x80 + WTERMSIG(status);
3874 } else {
3875 // Unknown exit code; pass it through
3876 return status;
3877 }
3878 }
3879 }
3880
3881 // Get the default path to the core file
3882 // Returns the length of the string
3883 int os::get_core_path(char* buffer, size_t bufferSize) {
3884 int n = jio_snprintf(buffer, bufferSize, "/cores/core.%d", current_process_id());
3885
3886 // Truncate if theoretical string was longer than bufferSize
3887 n = MIN2(n, (int)bufferSize);
3888
3889 return n;
3890 }
3891
3892 #ifndef PRODUCT
3893 void TestReserveMemorySpecial_test() {
3894 // No tests available for this platform
3895 }
3896 #endif
3897
3898 bool os::start_debugging(char *buf, int buflen) {
3899 int len = (int)strlen(buf);
3900 char *p = &buf[len];
3901
3902 jio_snprintf(p, buflen-len,
3903 "\n\n"
3904 "Do you want to debug the problem?\n\n"
3905 "To debug, run 'gdb /proc/%d/exe %d'; then switch to thread " INTX_FORMAT " (" INTPTR_FORMAT ")\n"
3906 "Enter 'yes' to launch gdb automatically (PATH must include gdb)\n"
3907 "Otherwise, press RETURN to abort...",
3908 os::current_process_id(), os::current_process_id(),
3909 os::current_thread_id(), os::current_thread_id());
3910
3911 bool yes = os::message_box("Unexpected Error", buf);
3912
3913 if (yes) {
3914 // yes, user asked VM to launch debugger
3915 jio_snprintf(buf, sizeof(buf), "gdb /proc/%d/exe %d",
3916 os::current_process_id(), os::current_process_id());
3917
3918 os::fork_and_exec(buf);
3919 yes = false;
3920 }
3921 return yes;
3922 }