1 /*
2 * Copyright (c) 1999, 2013, 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 "classfile/classLoader.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "classfile/vmSymbols.hpp"
29 #include "code/icBuffer.hpp"
30 #include "code/vtableStubs.hpp"
31 #include "compiler/compileBroker.hpp"
32 #include "compiler/disassembler.hpp"
33 #include "interpreter/interpreter.hpp"
34 #include "jvm_bsd.h"
35 #include "memory/allocation.inline.hpp"
36 #include "memory/filemap.hpp"
37 #include "mutex_bsd.inline.hpp"
38 #include "oops/oop.inline.hpp"
39 #include "os_share_bsd.hpp"
40 #include "prims/jniFastGetField.hpp"
41 #include "prims/jvm.h"
42 #include "prims/jvm_misc.hpp"
43 #include "runtime/arguments.hpp"
44 #include "runtime/extendedPC.hpp"
45 #include "runtime/globals.hpp"
46 #include "runtime/interfaceSupport.hpp"
47 #include "runtime/java.hpp"
48 #include "runtime/javaCalls.hpp"
49 #include "runtime/mutexLocker.hpp"
50 #include "runtime/objectMonitor.hpp"
51 #include "runtime/osThread.hpp"
52 #include "runtime/perfMemory.hpp"
53 #include "runtime/sharedRuntime.hpp"
54 #include "runtime/statSampler.hpp"
55 #include "runtime/stubRoutines.hpp"
56 #include "runtime/thread.inline.hpp"
57 #include "runtime/threadCritical.hpp"
58 #include "runtime/timer.hpp"
59 #include "services/attachListener.hpp"
60 #include "services/memTracker.hpp"
61 #include "services/runtimeService.hpp"
62 #include "utilities/decoder.hpp"
63 #include "utilities/defaultStream.hpp"
64 #include "utilities/events.hpp"
65 #include "utilities/growableArray.hpp"
66 #include "utilities/vmError.hpp"
67
68 // put OS-includes here
69 # include <sys/types.h>
70 # include <sys/mman.h>
71 # include <sys/stat.h>
72 # include <sys/select.h>
73 # include <pthread.h>
74 # include <signal.h>
75 # include <errno.h>
76 # include <dlfcn.h>
77 # include <stdio.h>
78 # include <unistd.h>
79 # include <sys/resource.h>
80 # include <pthread.h>
81 # include <sys/stat.h>
82 # include <sys/time.h>
83 # include <sys/times.h>
84 # include <sys/utsname.h>
85 # include <sys/socket.h>
86 # include <sys/wait.h>
87 # include <time.h>
88 # include <pwd.h>
89 # include <poll.h>
90 # include <semaphore.h>
91 # include <fcntl.h>
92 # include <string.h>
93 # include <sys/param.h>
94 # include <sys/sysctl.h>
95 # include <sys/ipc.h>
96 # include <sys/shm.h>
97 #ifndef __APPLE__
98 # include <link.h>
99 #endif
100 # include <stdint.h>
101 # include <inttypes.h>
102 # include <sys/ioctl.h>
103
104 #if defined(__FreeBSD__) || defined(__NetBSD__)
105 # include <elf.h>
106 #endif
107
108 #ifdef __APPLE__
109 # include <mach/mach.h> // semaphore_* API
110 # include <mach-o/dyld.h>
111 # include <sys/proc_info.h>
112 # include <objc/objc-auto.h>
113 #endif
114
115 #ifndef MAP_ANONYMOUS
116 #define MAP_ANONYMOUS MAP_ANON
117 #endif
118
119 #define MAX_PATH (2 * K)
120
121 // for timer info max values which include all bits
122 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF)
123
124 #define LARGEPAGES_BIT (1 << 6)
125 ////////////////////////////////////////////////////////////////////////////////
126 // global variables
127 julong os::Bsd::_physical_memory = 0;
128
129
130 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL;
131 pthread_t os::Bsd::_main_thread;
132 int os::Bsd::_page_size = -1;
133
134 static jlong initial_time_count=0;
135
136 static int clock_tics_per_sec = 100;
137
138 // For diagnostics to print a message once. see run_periodic_checks
139 static sigset_t check_signal_done;
140 static bool check_signals = true;
141
142 static pid_t _initial_pid = 0;
143
144 /* Signal number used to suspend/resume a thread */
145
146 /* do not use any signal number less than SIGSEGV, see 4355769 */
147 static int SR_signum = SIGUSR2;
148 sigset_t SR_sigset;
149
150
151 ////////////////////////////////////////////////////////////////////////////////
152 // utility functions
153
154 static int SR_initialize();
155
156 julong os::available_memory() {
157 return Bsd::available_memory();
158 }
159
160 julong os::Bsd::available_memory() {
161 // XXXBSD: this is just a stopgap implementation
162 return physical_memory() >> 2;
163 }
164
165 julong os::physical_memory() {
166 return Bsd::physical_memory();
167 }
168
169 ////////////////////////////////////////////////////////////////////////////////
170 // environment support
171
172 bool os::getenv(const char* name, char* buf, int len) {
173 const char* val = ::getenv(name);
174 if (val != NULL && strlen(val) < (size_t)len) {
175 strcpy(buf, val);
176 return true;
177 }
178 if (len > 0) buf[0] = 0; // return a null string
179 return false;
180 }
181
182
183 // Return true if user is running as root.
184
185 bool os::have_special_privileges() {
186 static bool init = false;
187 static bool privileges = false;
188 if (!init) {
189 privileges = (getuid() != geteuid()) || (getgid() != getegid());
190 init = true;
191 }
192 return privileges;
193 }
194
195
196
197 // Cpu architecture string
198 #if defined(ZERO)
199 static char cpu_arch[] = ZERO_LIBARCH;
200 #elif defined(IA64)
201 static char cpu_arch[] = "ia64";
202 #elif defined(IA32)
203 static char cpu_arch[] = "i386";
204 #elif defined(AMD64)
205 static char cpu_arch[] = "amd64";
206 #elif defined(ARM)
207 static char cpu_arch[] = "arm";
208 #elif defined(PPC32)
209 static char cpu_arch[] = "ppc";
210 #elif defined(SPARC)
211 # ifdef _LP64
212 static char cpu_arch[] = "sparcv9";
213 # else
214 static char cpu_arch[] = "sparc";
215 # endif
216 #else
217 #error Add appropriate cpu_arch setting
218 #endif
219
220 // Compiler variant
221 #ifdef COMPILER2
222 #define COMPILER_VARIANT "server"
223 #else
224 #define COMPILER_VARIANT "client"
225 #endif
226
227
228 void os::Bsd::initialize_system_info() {
229 int mib[2];
230 size_t len;
231 int cpu_val;
232 julong mem_val;
233
234 /* get processors count via hw.ncpus sysctl */
235 mib[0] = CTL_HW;
236 mib[1] = HW_NCPU;
237 len = sizeof(cpu_val);
238 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) {
239 assert(len == sizeof(cpu_val), "unexpected data size");
240 set_processor_count(cpu_val);
241 }
242 else {
243 set_processor_count(1); // fallback
244 }
245
246 /* get physical memory via hw.memsize sysctl (hw.memsize is used
247 * since it returns a 64 bit value)
248 */
249 mib[0] = CTL_HW;
250 mib[1] = HW_MEMSIZE;
251 len = sizeof(mem_val);
252 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) {
253 assert(len == sizeof(mem_val), "unexpected data size");
254 _physical_memory = mem_val;
255 } else {
256 _physical_memory = 256*1024*1024; // fallback (XXXBSD?)
257 }
258
259 #ifdef __OpenBSD__
260 {
261 // limit _physical_memory memory view on OpenBSD since
262 // datasize rlimit restricts us anyway.
263 struct rlimit limits;
264 getrlimit(RLIMIT_DATA, &limits);
265 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur);
266 }
267 #endif
268 }
269
270 #ifdef __APPLE__
271 static const char *get_home() {
272 const char *home_dir = ::getenv("HOME");
273 if ((home_dir == NULL) || (*home_dir == '\0')) {
274 struct passwd *passwd_info = getpwuid(geteuid());
275 if (passwd_info != NULL) {
276 home_dir = passwd_info->pw_dir;
277 }
278 }
279
280 return home_dir;
281 }
282 #endif
283
284 void os::init_system_properties_values() {
285 // char arch[12];
286 // sysinfo(SI_ARCHITECTURE, arch, sizeof(arch));
287
288 // The next steps are taken in the product version:
289 //
290 // Obtain the JAVA_HOME value from the location of libjvm.so.
291 // This library should be located at:
292 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so.
293 //
294 // If "/jre/lib/" appears at the right place in the path, then we
295 // assume libjvm.so is installed in a JDK and we use this path.
296 //
297 // Otherwise exit with message: "Could not create the Java virtual machine."
298 //
299 // The following extra steps are taken in the debugging version:
300 //
301 // If "/jre/lib/" does NOT appear at the right place in the path
302 // instead of exit check for $JAVA_HOME environment variable.
303 //
304 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>,
305 // then we append a fake suffix "hotspot/libjvm.so" to this path so
306 // it looks like libjvm.so is installed there
307 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so.
308 //
309 // Otherwise exit.
310 //
311 // Important note: if the location of libjvm.so changes this
312 // code needs to be changed accordingly.
313
314 // The next few definitions allow the code to be verbatim:
315 #define malloc(n) (char*)NEW_C_HEAP_ARRAY(char, (n), mtInternal)
316 #define getenv(n) ::getenv(n)
317
318 /*
319 * See ld(1):
320 * The linker uses the following search paths to locate required
321 * shared libraries:
322 * 1: ...
323 * ...
324 * 7: The default directories, normally /lib and /usr/lib.
325 */
326 #ifndef DEFAULT_LIBPATH
327 #define DEFAULT_LIBPATH "/lib:/usr/lib"
328 #endif
329
330 #define EXTENSIONS_DIR "/lib/ext"
331 #define ENDORSED_DIR "/lib/endorsed"
332 #define REG_DIR "/usr/java/packages"
333
334 #ifdef __APPLE__
335 #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions"
336 #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java"
337 const char *user_home_dir = get_home();
338 // the null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir
339 int system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) +
340 sizeof(SYS_EXTENSIONS_DIRS);
341 #endif
342
343 {
344 /* sysclasspath, java_home, dll_dir */
345 {
346 char *home_path;
347 char *dll_path;
348 char *pslash;
349 char buf[MAXPATHLEN];
350 os::jvm_path(buf, sizeof(buf));
351
352 // Found the full path to libjvm.so.
353 // Now cut the path to <java_home>/jre if we can.
354 *(strrchr(buf, '/')) = '\0'; /* get rid of /libjvm.so */
355 pslash = strrchr(buf, '/');
356 if (pslash != NULL)
357 *pslash = '\0'; /* get rid of /{client|server|hotspot} */
358 dll_path = malloc(strlen(buf) + 1);
359 if (dll_path == NULL)
360 return;
361 strcpy(dll_path, buf);
362 Arguments::set_dll_dir(dll_path);
363
364 if (pslash != NULL) {
365 pslash = strrchr(buf, '/');
366 if (pslash != NULL) {
367 *pslash = '\0'; /* get rid of /<arch> (/lib on macosx) */
368 #ifndef __APPLE__
369 pslash = strrchr(buf, '/');
370 if (pslash != NULL)
371 *pslash = '\0'; /* get rid of /lib */
372 #endif
373 }
374 }
375
376 home_path = malloc(strlen(buf) + 1);
377 if (home_path == NULL)
378 return;
379 strcpy(home_path, buf);
380 Arguments::set_java_home(home_path);
381
382 if (!set_boot_path('/', ':'))
383 return;
384 }
385
386 /*
387 * Where to look for native libraries
388 *
389 * Note: Due to a legacy implementation, most of the library path
390 * is set in the launcher. This was to accomodate linking restrictions
391 * on legacy Bsd implementations (which are no longer supported).
392 * Eventually, all the library path setting will be done here.
393 *
394 * However, to prevent the proliferation of improperly built native
395 * libraries, the new path component /usr/java/packages is added here.
396 * Eventually, all the library path setting will be done here.
397 */
398 {
399 char *ld_library_path;
400
401 /*
402 * Construct the invariant part of ld_library_path. Note that the
403 * space for the colon and the trailing null are provided by the
404 * nulls included by the sizeof operator (so actually we allocate
405 * a byte more than necessary).
406 */
407 #ifdef __APPLE__
408 ld_library_path = (char *) malloc(system_ext_size);
409 sprintf(ld_library_path, "%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS, user_home_dir);
410 #else
411 ld_library_path = (char *) malloc(sizeof(REG_DIR) + sizeof("/lib/") +
412 strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH));
413 sprintf(ld_library_path, REG_DIR "/lib/%s:" DEFAULT_LIBPATH, cpu_arch);
414 #endif
415
416 /*
417 * Get the user setting of LD_LIBRARY_PATH, and prepended it. It
418 * should always exist (until the legacy problem cited above is
419 * addressed).
420 */
421 #ifdef __APPLE__
422 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code can specify a directory inside an app wrapper
423 char *l = getenv("JAVA_LIBRARY_PATH");
424 if (l != NULL) {
425 char *t = ld_library_path;
426 /* That's +1 for the colon and +1 for the trailing '\0' */
427 ld_library_path = (char *) malloc(strlen(l) + 1 + strlen(t) + 1);
428 sprintf(ld_library_path, "%s:%s", l, t);
429 free(t);
430 }
431
432 char *v = getenv("DYLD_LIBRARY_PATH");
433 #else
434 char *v = getenv("LD_LIBRARY_PATH");
435 #endif
436 if (v != NULL) {
437 char *t = ld_library_path;
438 /* That's +1 for the colon and +1 for the trailing '\0' */
439 ld_library_path = (char *) malloc(strlen(v) + 1 + strlen(t) + 1);
440 sprintf(ld_library_path, "%s:%s", v, t);
441 free(t);
442 }
443
444 #ifdef __APPLE__
445 // Apple's Java6 has "." at the beginning of java.library.path.
446 // OpenJDK on Windows has "." at the end of java.library.path.
447 // OpenJDK on Linux and Solaris don't have "." in java.library.path
448 // at all. To ease the transition from Apple's Java6 to OpenJDK7,
449 // "." is appended to the end of java.library.path. Yes, this
450 // could cause a change in behavior, but Apple's Java6 behavior
451 // can be achieved by putting "." at the beginning of the
452 // JAVA_LIBRARY_PATH environment variable.
453 {
454 char *t = ld_library_path;
455 // that's +3 for appending ":." and the trailing '\0'
456 ld_library_path = (char *) malloc(strlen(t) + 3);
457 sprintf(ld_library_path, "%s:%s", t, ".");
458 free(t);
459 }
460 #endif
461
462 Arguments::set_library_path(ld_library_path);
463 }
464
465 /*
466 * Extensions directories.
467 *
468 * Note that the space for the colon and the trailing null are provided
469 * by the nulls included by the sizeof operator (so actually one byte more
470 * than necessary is allocated).
471 */
472 {
473 #ifdef __APPLE__
474 char *buf = malloc(strlen(Arguments::get_java_home()) +
475 sizeof(EXTENSIONS_DIR) + system_ext_size);
476 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":"
477 SYS_EXTENSIONS_DIRS, user_home_dir, Arguments::get_java_home());
478 #else
479 char *buf = malloc(strlen(Arguments::get_java_home()) +
480 sizeof(EXTENSIONS_DIR) + sizeof(REG_DIR) + sizeof(EXTENSIONS_DIR));
481 sprintf(buf, "%s" EXTENSIONS_DIR ":" REG_DIR EXTENSIONS_DIR,
482 Arguments::get_java_home());
483 #endif
484
485 Arguments::set_ext_dirs(buf);
486 }
487
488 /* Endorsed standards default directory. */
489 {
490 char * buf;
491 buf = malloc(strlen(Arguments::get_java_home()) + sizeof(ENDORSED_DIR));
492 sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home());
493 Arguments::set_endorsed_dirs(buf);
494 }
495 }
496
497 #ifdef __APPLE__
498 #undef SYS_EXTENSIONS_DIR
499 #endif
500 #undef malloc
501 #undef getenv
502 #undef EXTENSIONS_DIR
503 #undef ENDORSED_DIR
504
505 // Done
506 return;
507 }
508
509 ////////////////////////////////////////////////////////////////////////////////
510 // breakpoint support
511
512 void os::breakpoint() {
513 BREAKPOINT;
514 }
515
516 extern "C" void breakpoint() {
517 // use debugger to set breakpoint here
518 }
519
520 ////////////////////////////////////////////////////////////////////////////////
521 // signal support
522
523 debug_only(static bool signal_sets_initialized = false);
524 static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs;
525
526 bool os::Bsd::is_sig_ignored(int sig) {
527 struct sigaction oact;
528 sigaction(sig, (struct sigaction*)NULL, &oact);
529 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction)
530 : CAST_FROM_FN_PTR(void*, oact.sa_handler);
531 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN))
532 return true;
533 else
534 return false;
535 }
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 sigemptyset(&allowdebug_blocked_sigs);
555 sigaddset(&unblocked_sigs, SIGILL);
556 sigaddset(&unblocked_sigs, SIGSEGV);
557 sigaddset(&unblocked_sigs, SIGBUS);
558 sigaddset(&unblocked_sigs, SIGFPE);
559 sigaddset(&unblocked_sigs, SR_signum);
560
561 if (!ReduceSignalUsage) {
562 if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
563 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
564 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL);
565 }
566 if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
567 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
568 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL);
569 }
570 if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
571 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
572 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL);
573 }
574 }
575 // Fill in signals that are blocked by all but the VM thread.
576 sigemptyset(&vm_sigs);
577 if (!ReduceSignalUsage)
578 sigaddset(&vm_sigs, BREAK_SIGNAL);
579 debug_only(signal_sets_initialized = true);
580
581 }
582
583 // These are signals that are unblocked while a thread is running Java.
584 // (For some reason, they get blocked by default.)
585 sigset_t* os::Bsd::unblocked_signals() {
586 assert(signal_sets_initialized, "Not initialized");
587 return &unblocked_sigs;
588 }
589
590 // These are the signals that are blocked while a (non-VM) thread is
591 // running Java. Only the VM thread handles these signals.
592 sigset_t* os::Bsd::vm_signals() {
593 assert(signal_sets_initialized, "Not initialized");
594 return &vm_sigs;
595 }
596
597 // These are signals that are blocked during cond_wait to allow debugger in
598 sigset_t* os::Bsd::allowdebug_blocked_signals() {
599 assert(signal_sets_initialized, "Not initialized");
600 return &allowdebug_blocked_sigs;
601 }
602
603 void os::Bsd::hotspot_sigmask(Thread* thread) {
604
605 //Save caller's signal mask before setting VM signal mask
606 sigset_t caller_sigmask;
607 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
608
609 OSThread* osthread = thread->osthread();
610 osthread->set_caller_sigmask(caller_sigmask);
611
612 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL);
613
614 if (!ReduceSignalUsage) {
615 if (thread->is_VM_thread()) {
616 // Only the VM thread handles BREAK_SIGNAL ...
617 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
618 } else {
619 // ... all other threads block BREAK_SIGNAL
620 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
621 }
622 }
623 }
624
625
626 //////////////////////////////////////////////////////////////////////////////
627 // create new thread
628
629 // check if it's safe to start a new thread
630 static bool _thread_safety_check(Thread* thread) {
631 return true;
632 }
633
634 #ifdef __APPLE__
635 // library handle for calling objc_registerThreadWithCollector()
636 // without static linking to the libobjc library
637 #define OBJC_LIB "/usr/lib/libobjc.dylib"
638 #define OBJC_GCREGISTER "objc_registerThreadWithCollector"
639 typedef void (*objc_registerThreadWithCollector_t)();
640 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction;
641 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL;
642 #endif
643
644 #ifdef __APPLE__
645 static uint64_t locate_unique_thread_id() {
646 // Additional thread_id used to correlate threads in SA
647 thread_identifier_info_data_t m_ident_info;
648 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT;
649
650 thread_info(::mach_thread_self(), THREAD_IDENTIFIER_INFO,
651 (thread_info_t) &m_ident_info, &count);
652 return m_ident_info.thread_id;
653 }
654 #endif
655
656 // Thread start routine for all newly created threads
657 static void *java_start(Thread *thread) {
658 // Try to randomize the cache line index of hot stack frames.
659 // This helps when threads of the same stack traces evict each other's
660 // cache lines. The threads can be either from the same JVM instance, or
661 // from different JVM instances. The benefit is especially true for
662 // processors with hyperthreading technology.
663 static int counter = 0;
664 int pid = os::current_process_id();
665 alloca(((pid ^ counter++) & 7) * 128);
666
667 ThreadLocalStorage::set_thread(thread);
668
669 OSThread* osthread = thread->osthread();
670 Monitor* sync = osthread->startThread_lock();
671
672 // non floating stack BsdThreads needs extra check, see above
673 if (!_thread_safety_check(thread)) {
674 // notify parent thread
675 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
676 osthread->set_state(ZOMBIE);
677 sync->notify_all();
678 return NULL;
679 }
680
681 #ifdef __APPLE__
682 // thread_id is mach thread on macos
683 osthread->set_thread_id(::mach_thread_self());
684 osthread->set_unique_thread_id(locate_unique_thread_id());
685 #else
686 // thread_id is pthread_id on BSD
687 osthread->set_thread_id(::pthread_self());
688 #endif
689 // initialize signal mask for this thread
690 os::Bsd::hotspot_sigmask(thread);
691
692 // initialize floating point control register
693 os::Bsd::init_thread_fpu_state();
694
695 #ifdef __APPLE__
696 // register thread with objc gc
697 if (objc_registerThreadWithCollectorFunction != NULL) {
698 objc_registerThreadWithCollectorFunction();
699 }
700 #endif
701
702 // handshaking with parent thread
703 {
704 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
705
706 // notify parent thread
707 osthread->set_state(INITIALIZED);
708 sync->notify_all();
709
710 // wait until os::start_thread()
711 while (osthread->get_state() == INITIALIZED) {
712 sync->wait(Mutex::_no_safepoint_check_flag);
713 }
714 }
715
716 // call one more level start routine
717 thread->run();
718
719 return 0;
720 }
721
722 bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) {
723 assert(thread->osthread() == NULL, "caller responsible");
724
725 // Allocate the OSThread object
726 OSThread* osthread = new OSThread(NULL, NULL);
727 if (osthread == NULL) {
728 return false;
729 }
730
731 // set the correct thread state
732 osthread->set_thread_type(thr_type);
733
734 // Initial state is ALLOCATED but not INITIALIZED
735 osthread->set_state(ALLOCATED);
736
737 thread->set_osthread(osthread);
738
739 // init thread attributes
740 pthread_attr_t attr;
741 pthread_attr_init(&attr);
742 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
743
744 // stack size
745 if (os::Bsd::supports_variable_stack_size()) {
746 // calculate stack size if it's not specified by caller
747 if (stack_size == 0) {
748 stack_size = os::Bsd::default_stack_size(thr_type);
749
750 switch (thr_type) {
751 case os::java_thread:
752 // Java threads use ThreadStackSize which default value can be
753 // changed with the flag -Xss
754 assert (JavaThread::stack_size_at_create() > 0, "this should be set");
755 stack_size = JavaThread::stack_size_at_create();
756 break;
757 case os::compiler_thread:
758 if (CompilerThreadStackSize > 0) {
759 stack_size = (size_t)(CompilerThreadStackSize * K);
760 break;
761 } // else fall through:
762 // use VMThreadStackSize if CompilerThreadStackSize is not defined
763 case os::vm_thread:
764 case os::pgc_thread:
765 case os::cgc_thread:
766 case os::watcher_thread:
767 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K);
768 break;
769 }
770 }
771
772 stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed);
773 pthread_attr_setstacksize(&attr, stack_size);
774 } else {
775 // let pthread_create() pick the default value.
776 }
777
778 ThreadState state;
779
780 {
781 pthread_t tid;
782 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread);
783
784 pthread_attr_destroy(&attr);
785
786 if (ret != 0) {
787 if (PrintMiscellaneous && (Verbose || WizardMode)) {
788 perror("pthread_create()");
789 }
790 // Need to clean up stuff we've allocated so far
791 thread->set_osthread(NULL);
792 delete osthread;
793 return false;
794 }
795
796 // Store pthread info into the OSThread
797 osthread->set_pthread_id(tid);
798
799 // Wait until child thread is either initialized or aborted
800 {
801 Monitor* sync_with_child = osthread->startThread_lock();
802 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
803 while ((state = osthread->get_state()) == ALLOCATED) {
804 sync_with_child->wait(Mutex::_no_safepoint_check_flag);
805 }
806 }
807
808 }
809
810 // Aborted due to thread limit being reached
811 if (state == ZOMBIE) {
812 thread->set_osthread(NULL);
813 delete osthread;
814 return false;
815 }
816
817 // The thread is returned suspended (in state INITIALIZED),
818 // and is started higher up in the call chain
819 assert(state == INITIALIZED, "race condition");
820 return true;
821 }
822
823 /////////////////////////////////////////////////////////////////////////////
824 // attach existing thread
825
826 // bootstrap the main thread
827 bool os::create_main_thread(JavaThread* thread) {
828 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
829 return create_attached_thread(thread);
830 }
831
832 bool os::create_attached_thread(JavaThread* thread) {
833 #ifdef ASSERT
834 thread->verify_not_published();
835 #endif
836
837 // Allocate the OSThread object
838 OSThread* osthread = new OSThread(NULL, NULL);
839
840 if (osthread == NULL) {
841 return false;
842 }
843
844 // Store pthread info into the OSThread
845 #ifdef __APPLE__
846 osthread->set_thread_id(::mach_thread_self());
847 osthread->set_unique_thread_id(locate_unique_thread_id());
848 #else
849 osthread->set_thread_id(::pthread_self());
850 #endif
851 osthread->set_pthread_id(::pthread_self());
852
853 // initialize floating point control register
854 os::Bsd::init_thread_fpu_state();
855
856 // Initial thread state is RUNNABLE
857 osthread->set_state(RUNNABLE);
858
859 thread->set_osthread(osthread);
860
861 // initialize signal mask for this thread
862 // and save the caller's signal mask
863 os::Bsd::hotspot_sigmask(thread);
864
865 return true;
866 }
867
868 void os::pd_start_thread(Thread* thread) {
869 OSThread * osthread = thread->osthread();
870 assert(osthread->get_state() != INITIALIZED, "just checking");
871 Monitor* sync_with_child = osthread->startThread_lock();
872 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
873 sync_with_child->notify();
874 }
875
876 // Free Bsd resources related to the OSThread
877 void os::free_thread(OSThread* osthread) {
878 assert(osthread != NULL, "osthread not set");
879
880 if (Thread::current()->osthread() == osthread) {
881 // Restore caller's signal mask
882 sigset_t sigmask = osthread->caller_sigmask();
883 pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
884 }
885
886 delete osthread;
887 }
888
889 //////////////////////////////////////////////////////////////////////////////
890 // thread local storage
891
892 int os::allocate_thread_local_storage() {
893 pthread_key_t key;
894 int rslt = pthread_key_create(&key, NULL);
895 assert(rslt == 0, "cannot allocate thread local storage");
896 return (int)key;
897 }
898
899 // Note: This is currently not used by VM, as we don't destroy TLS key
900 // on VM exit.
901 void os::free_thread_local_storage(int index) {
902 int rslt = pthread_key_delete((pthread_key_t)index);
903 assert(rslt == 0, "invalid index");
904 }
905
906 void os::thread_local_storage_at_put(int index, void* value) {
907 int rslt = pthread_setspecific((pthread_key_t)index, value);
908 assert(rslt == 0, "pthread_setspecific failed");
909 }
910
911 extern "C" Thread* get_thread() {
912 return ThreadLocalStorage::thread();
913 }
914
915
916 ////////////////////////////////////////////////////////////////////////////////
917 // time support
918
919 // Time since start-up in seconds to a fine granularity.
920 // Used by VMSelfDestructTimer and the MemProfiler.
921 double os::elapsedTime() {
922
923 return (double)(os::elapsed_counter()) * 0.000001;
924 }
925
926 jlong os::elapsed_counter() {
927 timeval time;
928 int status = gettimeofday(&time, NULL);
929 return jlong(time.tv_sec) * 1000 * 1000 + jlong(time.tv_usec) - initial_time_count;
930 }
931
932 jlong os::elapsed_frequency() {
933 return (1000 * 1000);
934 }
935
936 bool os::supports_vtime() { return true; }
937 bool os::enable_vtime() { return false; }
938 bool os::vtime_enabled() { return false; }
939
940 double os::elapsedVTime() {
941 // better than nothing, but not much
942 return elapsedTime();
943 }
944
945 jlong os::javaTimeMillis() {
946 timeval time;
947 int status = gettimeofday(&time, NULL);
948 assert(status != -1, "bsd error");
949 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
950 }
951
952 #ifndef CLOCK_MONOTONIC
953 #define CLOCK_MONOTONIC (1)
954 #endif
955
956 #ifdef __APPLE__
957 void os::Bsd::clock_init() {
958 // XXXDARWIN: Investigate replacement monotonic clock
959 }
960 #else
961 void os::Bsd::clock_init() {
962 struct timespec res;
963 struct timespec tp;
964 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
965 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) {
966 // yes, monotonic clock is supported
967 _clock_gettime = ::clock_gettime;
968 }
969 }
970 #endif
971
972
973 jlong os::javaTimeNanos() {
974 if (Bsd::supports_monotonic_clock()) {
975 struct timespec tp;
976 int status = Bsd::clock_gettime(CLOCK_MONOTONIC, &tp);
977 assert(status == 0, "gettime error");
978 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
979 return result;
980 } else {
981 timeval time;
982 int status = gettimeofday(&time, NULL);
983 assert(status != -1, "bsd error");
984 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
985 return 1000 * usecs;
986 }
987 }
988
989 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
990 if (Bsd::supports_monotonic_clock()) {
991 info_ptr->max_value = ALL_64_BITS;
992
993 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
994 info_ptr->may_skip_backward = false; // not subject to resetting or drifting
995 info_ptr->may_skip_forward = false; // not subject to resetting or drifting
996 } else {
997 // gettimeofday - based on time in seconds since the Epoch thus does not wrap
998 info_ptr->max_value = ALL_64_BITS;
999
1000 // gettimeofday is a real time clock so it skips
1001 info_ptr->may_skip_backward = true;
1002 info_ptr->may_skip_forward = true;
1003 }
1004
1005 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
1006 }
1007
1008 // Return the real, user, and system times in seconds from an
1009 // arbitrary fixed point in the past.
1010 bool os::getTimesSecs(double* process_real_time,
1011 double* process_user_time,
1012 double* process_system_time) {
1013 struct tms ticks;
1014 clock_t real_ticks = times(&ticks);
1015
1016 if (real_ticks == (clock_t) (-1)) {
1017 return false;
1018 } else {
1019 double ticks_per_second = (double) clock_tics_per_sec;
1020 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1021 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1022 *process_real_time = ((double) real_ticks) / ticks_per_second;
1023
1024 return true;
1025 }
1026 }
1027
1028
1029 char * os::local_time_string(char *buf, size_t buflen) {
1030 struct tm t;
1031 time_t long_time;
1032 time(&long_time);
1033 localtime_r(&long_time, &t);
1034 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1035 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1036 t.tm_hour, t.tm_min, t.tm_sec);
1037 return buf;
1038 }
1039
1040 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
1041 return localtime_r(clock, res);
1042 }
1043
1044 ////////////////////////////////////////////////////////////////////////////////
1045 // runtime exit support
1046
1047 // Note: os::shutdown() might be called very early during initialization, or
1048 // called from signal handler. Before adding something to os::shutdown(), make
1049 // sure it is async-safe and can handle partially initialized VM.
1050 void os::shutdown() {
1051
1052 // allow PerfMemory to attempt cleanup of any persistent resources
1053 perfMemory_exit();
1054
1055 // needs to remove object in file system
1056 AttachListener::abort();
1057
1058 // flush buffered output, finish log files
1059 ostream_abort();
1060
1061 // Check for abort hook
1062 abort_hook_t abort_hook = Arguments::abort_hook();
1063 if (abort_hook != NULL) {
1064 abort_hook();
1065 }
1066
1067 }
1068
1069 // Note: os::abort() might be called very early during initialization, or
1070 // called from signal handler. Before adding something to os::abort(), make
1071 // sure it is async-safe and can handle partially initialized VM.
1072 void os::abort(bool dump_core) {
1073 os::shutdown();
1074 if (dump_core) {
1075 #ifndef PRODUCT
1076 fdStream out(defaultStream::output_fd());
1077 out.print_raw("Current thread is ");
1078 char buf[16];
1079 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
1080 out.print_raw_cr(buf);
1081 out.print_raw_cr("Dumping core ...");
1082 #endif
1083 ::abort(); // dump core
1084 }
1085
1086 ::exit(1);
1087 }
1088
1089 // Die immediately, no exit hook, no abort hook, no cleanup.
1090 void os::die() {
1091 // _exit() on BsdThreads only kills current thread
1092 ::abort();
1093 }
1094
1095 // unused on bsd for now.
1096 void os::set_error_file(const char *logfile) {}
1097
1098
1099 // This method is a copy of JDK's sysGetLastErrorString
1100 // from src/solaris/hpi/src/system_md.c
1101
1102 size_t os::lasterror(char *buf, size_t len) {
1103
1104 if (errno == 0) return 0;
1105
1106 const char *s = ::strerror(errno);
1107 size_t n = ::strlen(s);
1108 if (n >= len) {
1109 n = len - 1;
1110 }
1111 ::strncpy(buf, s, n);
1112 buf[n] = '\0';
1113 return n;
1114 }
1115
1116 intx os::current_thread_id() {
1117 #ifdef __APPLE__
1118 return (intx)::mach_thread_self();
1119 #else
1120 return (intx)::pthread_self();
1121 #endif
1122 }
1123 int os::current_process_id() {
1124
1125 // Under the old bsd thread library, bsd gives each thread
1126 // its own process id. Because of this each thread will return
1127 // a different pid if this method were to return the result
1128 // of getpid(2). Bsd provides no api that returns the pid
1129 // of the launcher thread for the vm. This implementation
1130 // returns a unique pid, the pid of the launcher thread
1131 // that starts the vm 'process'.
1132
1133 // Under the NPTL, getpid() returns the same pid as the
1134 // launcher thread rather than a unique pid per thread.
1135 // Use gettid() if you want the old pre NPTL behaviour.
1136
1137 // if you are looking for the result of a call to getpid() that
1138 // returns a unique pid for the calling thread, then look at the
1139 // OSThread::thread_id() method in osThread_bsd.hpp file
1140
1141 return (int)(_initial_pid ? _initial_pid : getpid());
1142 }
1143
1144 // DLL functions
1145
1146 #define JNI_LIB_PREFIX "lib"
1147 #ifdef __APPLE__
1148 #define JNI_LIB_SUFFIX ".dylib"
1149 #else
1150 #define JNI_LIB_SUFFIX ".so"
1151 #endif
1152
1153 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1154
1155 // This must be hard coded because it's the system's temporary
1156 // directory not the java application's temp directory, ala java.io.tmpdir.
1157 #ifdef __APPLE__
1158 // macosx has a secure per-user temporary directory
1159 char temp_path_storage[PATH_MAX];
1160 const char* os::get_temp_directory() {
1161 static char *temp_path = NULL;
1162 if (temp_path == NULL) {
1163 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
1164 if (pathSize == 0 || pathSize > PATH_MAX) {
1165 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
1166 }
1167 temp_path = temp_path_storage;
1168 }
1169 return temp_path;
1170 }
1171 #else /* __APPLE__ */
1172 const char* os::get_temp_directory() { return "/tmp"; }
1173 #endif /* __APPLE__ */
1174
1175 static bool file_exists(const char* filename) {
1176 struct stat statbuf;
1177 if (filename == NULL || strlen(filename) == 0) {
1178 return false;
1179 }
1180 return os::stat(filename, &statbuf) == 0;
1181 }
1182
1183 bool os::dll_build_name(char* buffer, size_t buflen,
1184 const char* pname, const char* fname) {
1185 bool retval = false;
1186 // Copied from libhpi
1187 const size_t pnamelen = pname ? strlen(pname) : 0;
1188
1189 // Return error on buffer overflow.
1190 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) {
1191 return retval;
1192 }
1193
1194 if (pnamelen == 0) {
1195 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname);
1196 retval = true;
1197 } else if (strchr(pname, *os::path_separator()) != NULL) {
1198 int n;
1199 char** pelements = split_path(pname, &n);
1200 if (pelements == NULL) {
1201 return false;
1202 }
1203 for (int i = 0 ; i < n ; i++) {
1204 // Really shouldn't be NULL, but check can't hurt
1205 if (pelements[i] == NULL || strlen(pelements[i]) == 0) {
1206 continue; // skip the empty path values
1207 }
1208 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX,
1209 pelements[i], fname);
1210 if (file_exists(buffer)) {
1211 retval = true;
1212 break;
1213 }
1214 }
1215 // release the storage
1216 for (int i = 0 ; i < n ; i++) {
1217 if (pelements[i] != NULL) {
1218 FREE_C_HEAP_ARRAY(char, pelements[i], mtInternal);
1219 }
1220 }
1221 if (pelements != NULL) {
1222 FREE_C_HEAP_ARRAY(char*, pelements, mtInternal);
1223 }
1224 } else {
1225 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname);
1226 retval = true;
1227 }
1228 return retval;
1229 }
1230
1231 // check if addr is inside libjvm.so
1232 bool os::address_is_in_vm(address addr) {
1233 static address libjvm_base_addr;
1234 Dl_info dlinfo;
1235
1236 if (libjvm_base_addr == NULL) {
1237 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) {
1238 libjvm_base_addr = (address)dlinfo.dli_fbase;
1239 }
1240 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1241 }
1242
1243 if (dladdr((void *)addr, &dlinfo) != 0) {
1244 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1245 }
1246
1247 return false;
1248 }
1249
1250
1251 #define MACH_MAXSYMLEN 256
1252
1253 bool os::dll_address_to_function_name(address addr, char *buf,
1254 int buflen, int *offset) {
1255 // buf is not optional, but offset is optional
1256 assert(buf != NULL, "sanity check");
1257
1258 Dl_info dlinfo;
1259 char localbuf[MACH_MAXSYMLEN];
1260
1261 if (dladdr((void*)addr, &dlinfo) != 0) {
1262 // see if we have a matching symbol
1263 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) {
1264 if (!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) {
1265 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1266 }
1267 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1268 return true;
1269 }
1270 // no matching symbol so try for just file info
1271 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) {
1272 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1273 buf, buflen, offset, dlinfo.dli_fname)) {
1274 return true;
1275 }
1276 }
1277
1278 // Handle non-dynamic manually:
1279 if (dlinfo.dli_fbase != NULL &&
1280 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset,
1281 dlinfo.dli_fbase)) {
1282 if (!Decoder::demangle(localbuf, buf, buflen)) {
1283 jio_snprintf(buf, buflen, "%s", localbuf);
1284 }
1285 return true;
1286 }
1287 }
1288 buf[0] = '\0';
1289 if (offset != NULL) *offset = -1;
1290 return false;
1291 }
1292
1293 // ported from solaris version
1294 bool os::dll_address_to_library_name(address addr, char* buf,
1295 int buflen, int* offset) {
1296 // buf is not optional, but offset is optional
1297 assert(buf != NULL, "sanity check");
1298
1299 Dl_info dlinfo;
1300
1301 if (dladdr((void*)addr, &dlinfo) != 0) {
1302 if (dlinfo.dli_fname != NULL) {
1303 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1304 }
1305 if (dlinfo.dli_fbase != NULL && offset != NULL) {
1306 *offset = addr - (address)dlinfo.dli_fbase;
1307 }
1308 return true;
1309 }
1310
1311 buf[0] = '\0';
1312 if (offset) *offset = -1;
1313 return false;
1314 }
1315
1316 // Loads .dll/.so and
1317 // in case of error it checks if .dll/.so was built for the
1318 // same architecture as Hotspot is running on
1319
1320 #ifdef __APPLE__
1321 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1322 void * result= ::dlopen(filename, RTLD_LAZY);
1323 if (result != NULL) {
1324 // Successful loading
1325 return result;
1326 }
1327
1328 // Read system error message into ebuf
1329 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1330 ebuf[ebuflen-1]='\0';
1331
1332 return NULL;
1333 }
1334 #else
1335 void * os::dll_load(const char *filename, char *ebuf, int ebuflen)
1336 {
1337 void * result= ::dlopen(filename, RTLD_LAZY);
1338 if (result != NULL) {
1339 // Successful loading
1340 return result;
1341 }
1342
1343 Elf32_Ehdr elf_head;
1344
1345 // Read system error message into ebuf
1346 // It may or may not be overwritten below
1347 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1348 ebuf[ebuflen-1]='\0';
1349 int diag_msg_max_length=ebuflen-strlen(ebuf);
1350 char* diag_msg_buf=ebuf+strlen(ebuf);
1351
1352 if (diag_msg_max_length==0) {
1353 // No more space in ebuf for additional diagnostics message
1354 return NULL;
1355 }
1356
1357
1358 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1359
1360 if (file_descriptor < 0) {
1361 // Can't open library, report dlerror() message
1362 return NULL;
1363 }
1364
1365 bool failed_to_read_elf_head=
1366 (sizeof(elf_head)!=
1367 (::read(file_descriptor, &elf_head,sizeof(elf_head)))) ;
1368
1369 ::close(file_descriptor);
1370 if (failed_to_read_elf_head) {
1371 // file i/o error - report dlerror() msg
1372 return NULL;
1373 }
1374
1375 typedef struct {
1376 Elf32_Half code; // Actual value as defined in elf.h
1377 Elf32_Half compat_class; // Compatibility of archs at VM's sense
1378 char elf_class; // 32 or 64 bit
1379 char endianess; // MSB or LSB
1380 char* name; // String representation
1381 } arch_t;
1382
1383 #ifndef EM_486
1384 #define EM_486 6 /* Intel 80486 */
1385 #endif
1386
1387 #ifndef EM_MIPS_RS3_LE
1388 #define EM_MIPS_RS3_LE 10 /* MIPS */
1389 #endif
1390
1391 #ifndef EM_PPC64
1392 #define EM_PPC64 21 /* PowerPC64 */
1393 #endif
1394
1395 #ifndef EM_S390
1396 #define EM_S390 22 /* IBM System/390 */
1397 #endif
1398
1399 #ifndef EM_IA_64
1400 #define EM_IA_64 50 /* HP/Intel IA-64 */
1401 #endif
1402
1403 #ifndef EM_X86_64
1404 #define EM_X86_64 62 /* AMD x86-64 */
1405 #endif
1406
1407 static const arch_t arch_array[]={
1408 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1409 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1410 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
1411 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
1412 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1413 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1414 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
1415 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
1416 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
1417 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"},
1418 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
1419 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
1420 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
1421 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
1422 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
1423 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
1424 };
1425
1426 #if (defined IA32)
1427 static Elf32_Half running_arch_code=EM_386;
1428 #elif (defined AMD64)
1429 static Elf32_Half running_arch_code=EM_X86_64;
1430 #elif (defined IA64)
1431 static Elf32_Half running_arch_code=EM_IA_64;
1432 #elif (defined __sparc) && (defined _LP64)
1433 static Elf32_Half running_arch_code=EM_SPARCV9;
1434 #elif (defined __sparc) && (!defined _LP64)
1435 static Elf32_Half running_arch_code=EM_SPARC;
1436 #elif (defined __powerpc64__)
1437 static Elf32_Half running_arch_code=EM_PPC64;
1438 #elif (defined __powerpc__)
1439 static Elf32_Half running_arch_code=EM_PPC;
1440 #elif (defined ARM)
1441 static Elf32_Half running_arch_code=EM_ARM;
1442 #elif (defined S390)
1443 static Elf32_Half running_arch_code=EM_S390;
1444 #elif (defined ALPHA)
1445 static Elf32_Half running_arch_code=EM_ALPHA;
1446 #elif (defined MIPSEL)
1447 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
1448 #elif (defined PARISC)
1449 static Elf32_Half running_arch_code=EM_PARISC;
1450 #elif (defined MIPS)
1451 static Elf32_Half running_arch_code=EM_MIPS;
1452 #elif (defined M68K)
1453 static Elf32_Half running_arch_code=EM_68K;
1454 #else
1455 #error Method os::dll_load requires that one of following is defined:\
1456 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
1457 #endif
1458
1459 // Identify compatability class for VM's architecture and library's architecture
1460 // Obtain string descriptions for architectures
1461
1462 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
1463 int running_arch_index=-1;
1464
1465 for (unsigned int i=0 ; i < ARRAY_SIZE(arch_array) ; i++ ) {
1466 if (running_arch_code == arch_array[i].code) {
1467 running_arch_index = i;
1468 }
1469 if (lib_arch.code == arch_array[i].code) {
1470 lib_arch.compat_class = arch_array[i].compat_class;
1471 lib_arch.name = arch_array[i].name;
1472 }
1473 }
1474
1475 assert(running_arch_index != -1,
1476 "Didn't find running architecture code (running_arch_code) in arch_array");
1477 if (running_arch_index == -1) {
1478 // Even though running architecture detection failed
1479 // we may still continue with reporting dlerror() message
1480 return NULL;
1481 }
1482
1483 if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
1484 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
1485 return NULL;
1486 }
1487
1488 #ifndef S390
1489 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
1490 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
1491 return NULL;
1492 }
1493 #endif // !S390
1494
1495 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
1496 if ( lib_arch.name!=NULL ) {
1497 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1498 " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
1499 lib_arch.name, arch_array[running_arch_index].name);
1500 } else {
1501 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1502 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
1503 lib_arch.code,
1504 arch_array[running_arch_index].name);
1505 }
1506 }
1507
1508 return NULL;
1509 }
1510 #endif /* !__APPLE__ */
1511
1512 // XXX: Do we need a lock around this as per Linux?
1513 void* os::dll_lookup(void* handle, const char* name) {
1514 return dlsym(handle, name);
1515 }
1516
1517
1518 static bool _print_ascii_file(const char* filename, outputStream* st) {
1519 int fd = ::open(filename, O_RDONLY);
1520 if (fd == -1) {
1521 return false;
1522 }
1523
1524 char buf[32];
1525 int bytes;
1526 while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) {
1527 st->print_raw(buf, bytes);
1528 }
1529
1530 ::close(fd);
1531
1532 return true;
1533 }
1534
1535 void os::print_dll_info(outputStream *st) {
1536 st->print_cr("Dynamic libraries:");
1537 #ifdef RTLD_DI_LINKMAP
1538 Dl_info dli;
1539 void *handle;
1540 Link_map *map;
1541 Link_map *p;
1542
1543 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 ||
1544 dli.dli_fname == NULL) {
1545 st->print_cr("Error: Cannot print dynamic libraries.");
1546 return;
1547 }
1548 handle = dlopen(dli.dli_fname, RTLD_LAZY);
1549 if (handle == NULL) {
1550 st->print_cr("Error: Cannot print dynamic libraries.");
1551 return;
1552 }
1553 dlinfo(handle, RTLD_DI_LINKMAP, &map);
1554 if (map == NULL) {
1555 st->print_cr("Error: Cannot print dynamic libraries.");
1556 return;
1557 }
1558
1559 while (map->l_prev != NULL)
1560 map = map->l_prev;
1561
1562 while (map != NULL) {
1563 st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name);
1564 map = map->l_next;
1565 }
1566
1567 dlclose(handle);
1568 #elif defined(__APPLE__)
1569 uint32_t count;
1570 uint32_t i;
1571
1572 count = _dyld_image_count();
1573 for (i = 1; i < count; i++) {
1574 const char *name = _dyld_get_image_name(i);
1575 intptr_t slide = _dyld_get_image_vmaddr_slide(i);
1576 st->print_cr(PTR_FORMAT " \t%s", slide, name);
1577 }
1578 #else
1579 st->print_cr("Error: Cannot print dynamic libraries.");
1580 #endif
1581 }
1582
1583 void os::print_os_info_brief(outputStream* st) {
1584 st->print("Bsd");
1585
1586 os::Posix::print_uname_info(st);
1587 }
1588
1589 void os::print_os_info(outputStream* st) {
1590 st->print("OS:");
1591 st->print("Bsd");
1592
1593 os::Posix::print_uname_info(st);
1594
1595 os::Posix::print_rlimit_info(st);
1596
1597 os::Posix::print_load_average(st);
1598 }
1599
1600 void os::pd_print_cpu_info(outputStream* st) {
1601 // Nothing to do for now.
1602 }
1603
1604 void os::print_memory_info(outputStream* st) {
1605
1606 st->print("Memory:");
1607 st->print(" %dk page", os::vm_page_size()>>10);
1608
1609 st->print(", physical " UINT64_FORMAT "k",
1610 os::physical_memory() >> 10);
1611 st->print("(" UINT64_FORMAT "k free)",
1612 os::available_memory() >> 10);
1613 st->cr();
1614
1615 // meminfo
1616 st->print("\n/proc/meminfo:\n");
1617 _print_ascii_file("/proc/meminfo", st);
1618 st->cr();
1619 }
1620
1621 // Taken from /usr/include/bits/siginfo.h Supposed to be architecture specific
1622 // but they're the same for all the bsd arch that we support
1623 // and they're the same for solaris but there's no common place to put this.
1624 const char *ill_names[] = { "ILL0", "ILL_ILLOPC", "ILL_ILLOPN", "ILL_ILLADR",
1625 "ILL_ILLTRP", "ILL_PRVOPC", "ILL_PRVREG",
1626 "ILL_COPROC", "ILL_BADSTK" };
1627
1628 const char *fpe_names[] = { "FPE0", "FPE_INTDIV", "FPE_INTOVF", "FPE_FLTDIV",
1629 "FPE_FLTOVF", "FPE_FLTUND", "FPE_FLTRES",
1630 "FPE_FLTINV", "FPE_FLTSUB", "FPE_FLTDEN" };
1631
1632 const char *segv_names[] = { "SEGV0", "SEGV_MAPERR", "SEGV_ACCERR" };
1633
1634 const char *bus_names[] = { "BUS0", "BUS_ADRALN", "BUS_ADRERR", "BUS_OBJERR" };
1635
1636 void os::print_siginfo(outputStream* st, void* siginfo) {
1637 st->print("siginfo:");
1638
1639 const int buflen = 100;
1640 char buf[buflen];
1641 siginfo_t *si = (siginfo_t*)siginfo;
1642 st->print("si_signo=%s: ", os::exception_name(si->si_signo, buf, buflen));
1643 if (si->si_errno != 0 && strerror_r(si->si_errno, buf, buflen) == 0) {
1644 st->print("si_errno=%s", buf);
1645 } else {
1646 st->print("si_errno=%d", si->si_errno);
1647 }
1648 const int c = si->si_code;
1649 assert(c > 0, "unexpected si_code");
1650 switch (si->si_signo) {
1651 case SIGILL:
1652 st->print(", si_code=%d (%s)", c, c > 8 ? "" : ill_names[c]);
1653 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1654 break;
1655 case SIGFPE:
1656 st->print(", si_code=%d (%s)", c, c > 9 ? "" : fpe_names[c]);
1657 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1658 break;
1659 case SIGSEGV:
1660 st->print(", si_code=%d (%s)", c, c > 2 ? "" : segv_names[c]);
1661 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1662 break;
1663 case SIGBUS:
1664 st->print(", si_code=%d (%s)", c, c > 3 ? "" : bus_names[c]);
1665 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1666 break;
1667 default:
1668 st->print(", si_code=%d", si->si_code);
1669 // no si_addr
1670 }
1671
1672 if ((si->si_signo == SIGBUS || si->si_signo == SIGSEGV) &&
1673 UseSharedSpaces) {
1674 FileMapInfo* mapinfo = FileMapInfo::current_info();
1675 if (mapinfo->is_in_shared_space(si->si_addr)) {
1676 st->print("\n\nError accessing class data sharing archive." \
1677 " Mapped file inaccessible during execution, " \
1678 " possible disk/network problem.");
1679 }
1680 }
1681 st->cr();
1682 }
1683
1684
1685 static void print_signal_handler(outputStream* st, int sig,
1686 char* buf, size_t buflen);
1687
1688 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1689 st->print_cr("Signal Handlers:");
1690 print_signal_handler(st, SIGSEGV, buf, buflen);
1691 print_signal_handler(st, SIGBUS , buf, buflen);
1692 print_signal_handler(st, SIGFPE , buf, buflen);
1693 print_signal_handler(st, SIGPIPE, buf, buflen);
1694 print_signal_handler(st, SIGXFSZ, buf, buflen);
1695 print_signal_handler(st, SIGILL , buf, buflen);
1696 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen);
1697 print_signal_handler(st, SR_signum, buf, buflen);
1698 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1699 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1700 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1701 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1702 }
1703
1704 static char saved_jvm_path[MAXPATHLEN] = {0};
1705
1706 // Find the full path to the current module, libjvm
1707 void os::jvm_path(char *buf, jint buflen) {
1708 // Error checking.
1709 if (buflen < MAXPATHLEN) {
1710 assert(false, "must use a large-enough buffer");
1711 buf[0] = '\0';
1712 return;
1713 }
1714 // Lazy resolve the path to current module.
1715 if (saved_jvm_path[0] != 0) {
1716 strcpy(buf, saved_jvm_path);
1717 return;
1718 }
1719
1720 char dli_fname[MAXPATHLEN];
1721 bool ret = dll_address_to_library_name(
1722 CAST_FROM_FN_PTR(address, os::jvm_path),
1723 dli_fname, sizeof(dli_fname), NULL);
1724 assert(ret, "cannot locate libjvm");
1725 char *rp = NULL;
1726 if (ret && dli_fname[0] != '\0') {
1727 rp = realpath(dli_fname, buf);
1728 }
1729 if (rp == NULL)
1730 return;
1731
1732 if (Arguments::created_by_gamma_launcher()) {
1733 // Support for the gamma launcher. Typical value for buf is
1734 // "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm". If "/jre/lib/" appears at
1735 // the right place in the string, then assume we are installed in a JDK and
1736 // we're done. Otherwise, check for a JAVA_HOME environment variable and
1737 // construct a path to the JVM being overridden.
1738
1739 const char *p = buf + strlen(buf) - 1;
1740 for (int count = 0; p > buf && count < 5; ++count) {
1741 for (--p; p > buf && *p != '/'; --p)
1742 /* empty */ ;
1743 }
1744
1745 if (strncmp(p, "/jre/lib/", 9) != 0) {
1746 // Look for JAVA_HOME in the environment.
1747 char* java_home_var = ::getenv("JAVA_HOME");
1748 if (java_home_var != NULL && java_home_var[0] != 0) {
1749 char* jrelib_p;
1750 int len;
1751
1752 // Check the current module name "libjvm"
1753 p = strrchr(buf, '/');
1754 assert(strstr(p, "/libjvm") == p, "invalid library name");
1755
1756 rp = realpath(java_home_var, buf);
1757 if (rp == NULL)
1758 return;
1759
1760 // determine if this is a legacy image or modules image
1761 // modules image doesn't have "jre" subdirectory
1762 len = strlen(buf);
1763 jrelib_p = buf + len;
1764
1765 // Add the appropriate library subdir
1766 snprintf(jrelib_p, buflen-len, "/jre/lib");
1767 if (0 != access(buf, F_OK)) {
1768 snprintf(jrelib_p, buflen-len, "/lib");
1769 }
1770
1771 // Add the appropriate client or server subdir
1772 len = strlen(buf);
1773 jrelib_p = buf + len;
1774 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
1775 if (0 != access(buf, F_OK)) {
1776 snprintf(jrelib_p, buflen-len, "");
1777 }
1778
1779 // If the path exists within JAVA_HOME, add the JVM library name
1780 // to complete the path to JVM being overridden. Otherwise fallback
1781 // to the path to the current library.
1782 if (0 == access(buf, F_OK)) {
1783 // Use current module name "libjvm"
1784 len = strlen(buf);
1785 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
1786 } else {
1787 // Fall back to path of current library
1788 rp = realpath(dli_fname, buf);
1789 if (rp == NULL)
1790 return;
1791 }
1792 }
1793 }
1794 }
1795
1796 strcpy(saved_jvm_path, buf);
1797 }
1798
1799 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1800 // no prefix required, not even "_"
1801 }
1802
1803 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1804 // no suffix required
1805 }
1806
1807 ////////////////////////////////////////////////////////////////////////////////
1808 // sun.misc.Signal support
1809
1810 static volatile jint sigint_count = 0;
1811
1812 static void
1813 UserHandler(int sig, void *siginfo, void *context) {
1814 // 4511530 - sem_post is serialized and handled by the manager thread. When
1815 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
1816 // don't want to flood the manager thread with sem_post requests.
1817 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1)
1818 return;
1819
1820 // Ctrl-C is pressed during error reporting, likely because the error
1821 // handler fails to abort. Let VM die immediately.
1822 if (sig == SIGINT && is_error_reported()) {
1823 os::die();
1824 }
1825
1826 os::signal_notify(sig);
1827 }
1828
1829 void* os::user_handler() {
1830 return CAST_FROM_FN_PTR(void*, UserHandler);
1831 }
1832
1833 extern "C" {
1834 typedef void (*sa_handler_t)(int);
1835 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1836 }
1837
1838 void* os::signal(int signal_number, void* handler) {
1839 struct sigaction sigAct, oldSigAct;
1840
1841 sigfillset(&(sigAct.sa_mask));
1842 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
1843 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1844
1845 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1846 // -1 means registration failed
1847 return (void *)-1;
1848 }
1849
1850 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1851 }
1852
1853 void os::signal_raise(int signal_number) {
1854 ::raise(signal_number);
1855 }
1856
1857 /*
1858 * The following code is moved from os.cpp for making this
1859 * code platform specific, which it is by its very nature.
1860 */
1861
1862 // Will be modified when max signal is changed to be dynamic
1863 int os::sigexitnum_pd() {
1864 return NSIG;
1865 }
1866
1867 // a counter for each possible signal value
1868 static volatile jint pending_signals[NSIG+1] = { 0 };
1869
1870 // Bsd(POSIX) specific hand shaking semaphore.
1871 #ifdef __APPLE__
1872 typedef semaphore_t os_semaphore_t;
1873 #define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value)
1874 #define SEM_WAIT(sem) semaphore_wait(sem)
1875 #define SEM_POST(sem) semaphore_signal(sem)
1876 #define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem)
1877 #else
1878 typedef sem_t os_semaphore_t;
1879 #define SEM_INIT(sem, value) sem_init(&sem, 0, value)
1880 #define SEM_WAIT(sem) sem_wait(&sem)
1881 #define SEM_POST(sem) sem_post(&sem)
1882 #define SEM_DESTROY(sem) sem_destroy(&sem)
1883 #endif
1884
1885 class Semaphore : public StackObj {
1886 public:
1887 Semaphore();
1888 ~Semaphore();
1889 void signal();
1890 void wait();
1891 bool trywait();
1892 bool timedwait(unsigned int sec, int nsec);
1893 private:
1894 jlong currenttime() const;
1895 semaphore_t _semaphore;
1896 };
1897
1898 Semaphore::Semaphore() : _semaphore(0) {
1899 SEM_INIT(_semaphore, 0);
1900 }
1901
1902 Semaphore::~Semaphore() {
1903 SEM_DESTROY(_semaphore);
1904 }
1905
1906 void Semaphore::signal() {
1907 SEM_POST(_semaphore);
1908 }
1909
1910 void Semaphore::wait() {
1911 SEM_WAIT(_semaphore);
1912 }
1913
1914 jlong Semaphore::currenttime() const {
1915 struct timeval tv;
1916 gettimeofday(&tv, NULL);
1917 return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000);
1918 }
1919
1920 #ifdef __APPLE__
1921 bool Semaphore::trywait() {
1922 return timedwait(0, 0);
1923 }
1924
1925 bool Semaphore::timedwait(unsigned int sec, int nsec) {
1926 kern_return_t kr = KERN_ABORTED;
1927 mach_timespec_t waitspec;
1928 waitspec.tv_sec = sec;
1929 waitspec.tv_nsec = nsec;
1930
1931 jlong starttime = currenttime();
1932
1933 kr = semaphore_timedwait(_semaphore, waitspec);
1934 while (kr == KERN_ABORTED) {
1935 jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec;
1936
1937 jlong current = currenttime();
1938 jlong passedtime = current - starttime;
1939
1940 if (passedtime >= totalwait) {
1941 waitspec.tv_sec = 0;
1942 waitspec.tv_nsec = 0;
1943 } else {
1944 jlong waittime = totalwait - (current - starttime);
1945 waitspec.tv_sec = waittime / NANOSECS_PER_SEC;
1946 waitspec.tv_nsec = waittime % NANOSECS_PER_SEC;
1947 }
1948
1949 kr = semaphore_timedwait(_semaphore, waitspec);
1950 }
1951
1952 return kr == KERN_SUCCESS;
1953 }
1954
1955 #else
1956
1957 bool Semaphore::trywait() {
1958 return sem_trywait(&_semaphore) == 0;
1959 }
1960
1961 bool Semaphore::timedwait(unsigned int sec, int nsec) {
1962 struct timespec ts;
1963 jlong endtime = unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec);
1964
1965 while (1) {
1966 int result = sem_timedwait(&_semaphore, &ts);
1967 if (result == 0) {
1968 return true;
1969 } else if (errno == EINTR) {
1970 continue;
1971 } else if (errno == ETIMEDOUT) {
1972 return false;
1973 } else {
1974 return false;
1975 }
1976 }
1977 }
1978
1979 #endif // __APPLE__
1980
1981 static os_semaphore_t sig_sem;
1982 static Semaphore sr_semaphore;
1983
1984 void os::signal_init_pd() {
1985 // Initialize signal structures
1986 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
1987
1988 // Initialize signal semaphore
1989 ::SEM_INIT(sig_sem, 0);
1990 }
1991
1992 void os::signal_notify(int sig) {
1993 Atomic::inc(&pending_signals[sig]);
1994 ::SEM_POST(sig_sem);
1995 }
1996
1997 static int check_pending_signals(bool wait) {
1998 Atomic::store(0, &sigint_count);
1999 for (;;) {
2000 for (int i = 0; i < NSIG + 1; i++) {
2001 jint n = pending_signals[i];
2002 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
2003 return i;
2004 }
2005 }
2006 if (!wait) {
2007 return -1;
2008 }
2009 JavaThread *thread = JavaThread::current();
2010 ThreadBlockInVM tbivm(thread);
2011
2012 bool threadIsSuspended;
2013 do {
2014 thread->set_suspend_equivalent();
2015 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
2016 ::SEM_WAIT(sig_sem);
2017
2018 // were we externally suspended while we were waiting?
2019 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
2020 if (threadIsSuspended) {
2021 //
2022 // The semaphore has been incremented, but while we were waiting
2023 // another thread suspended us. We don't want to continue running
2024 // while suspended because that would surprise the thread that
2025 // suspended us.
2026 //
2027 ::SEM_POST(sig_sem);
2028
2029 thread->java_suspend_self();
2030 }
2031 } while (threadIsSuspended);
2032 }
2033 }
2034
2035 int os::signal_lookup() {
2036 return check_pending_signals(false);
2037 }
2038
2039 int os::signal_wait() {
2040 return check_pending_signals(true);
2041 }
2042
2043 ////////////////////////////////////////////////////////////////////////////////
2044 // Virtual Memory
2045
2046 int os::vm_page_size() {
2047 // Seems redundant as all get out
2048 assert(os::Bsd::page_size() != -1, "must call os::init");
2049 return os::Bsd::page_size();
2050 }
2051
2052 // Solaris allocates memory by pages.
2053 int os::vm_allocation_granularity() {
2054 assert(os::Bsd::page_size() != -1, "must call os::init");
2055 return os::Bsd::page_size();
2056 }
2057
2058 // Rationale behind this function:
2059 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
2060 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
2061 // samples for JITted code. Here we create private executable mapping over the code cache
2062 // and then we can use standard (well, almost, as mapping can change) way to provide
2063 // info for the reporting script by storing timestamp and location of symbol
2064 void bsd_wrap_code(char* base, size_t size) {
2065 static volatile jint cnt = 0;
2066
2067 if (!UseOprofile) {
2068 return;
2069 }
2070
2071 char buf[PATH_MAX + 1];
2072 int num = Atomic::add(1, &cnt);
2073
2074 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
2075 os::get_temp_directory(), os::current_process_id(), num);
2076 unlink(buf);
2077
2078 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
2079
2080 if (fd != -1) {
2081 off_t rv = ::lseek(fd, size-2, SEEK_SET);
2082 if (rv != (off_t)-1) {
2083 if (::write(fd, "", 1) == 1) {
2084 mmap(base, size,
2085 PROT_READ|PROT_WRITE|PROT_EXEC,
2086 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
2087 }
2088 }
2089 ::close(fd);
2090 unlink(buf);
2091 }
2092 }
2093
2094 static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
2095 int err) {
2096 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT
2097 ", %d) failed; error='%s' (errno=%d)", addr, size, exec,
2098 strerror(err), err);
2099 }
2100
2101 // NOTE: Bsd kernel does not really reserve the pages for us.
2102 // All it does is to check if there are enough free pages
2103 // left at the time of mmap(). This could be a potential
2104 // problem.
2105 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
2106 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
2107 #ifdef __OpenBSD__
2108 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2109 if (::mprotect(addr, size, prot) == 0) {
2110 return true;
2111 }
2112 #else
2113 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
2114 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
2115 if (res != (uintptr_t) MAP_FAILED) {
2116 return true;
2117 }
2118 #endif
2119
2120 // Warn about any commit errors we see in non-product builds just
2121 // in case mmap() doesn't work as described on the man page.
2122 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);)
2123
2124 return false;
2125 }
2126
2127 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
2128 bool exec) {
2129 // alignment_hint is ignored on this OS
2130 return pd_commit_memory(addr, size, exec);
2131 }
2132
2133 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
2134 const char* mesg) {
2135 assert(mesg != NULL, "mesg must be specified");
2136 if (!pd_commit_memory(addr, size, exec)) {
2137 // add extra info in product mode for vm_exit_out_of_memory():
2138 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
2139 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, mesg);
2140 }
2141 }
2142
2143 void os::pd_commit_memory_or_exit(char* addr, size_t size,
2144 size_t alignment_hint, bool exec,
2145 const char* mesg) {
2146 // alignment_hint is ignored on this OS
2147 pd_commit_memory_or_exit(addr, size, exec, mesg);
2148 }
2149
2150 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
2151 }
2152
2153 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
2154 ::madvise(addr, bytes, MADV_DONTNEED);
2155 }
2156
2157 void os::numa_make_global(char *addr, size_t bytes) {
2158 }
2159
2160 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
2161 }
2162
2163 bool os::numa_topology_changed() { return false; }
2164
2165 size_t os::numa_get_groups_num() {
2166 return 1;
2167 }
2168
2169 int os::numa_get_group_id() {
2170 return 0;
2171 }
2172
2173 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
2174 if (size > 0) {
2175 ids[0] = 0;
2176 return 1;
2177 }
2178 return 0;
2179 }
2180
2181 bool os::get_page_info(char *start, page_info* info) {
2182 return false;
2183 }
2184
2185 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2186 return end;
2187 }
2188
2189
2190 bool os::pd_uncommit_memory(char* addr, size_t size) {
2191 #ifdef __OpenBSD__
2192 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2193 return ::mprotect(addr, size, PROT_NONE) == 0;
2194 #else
2195 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
2196 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
2197 return res != (uintptr_t) MAP_FAILED;
2198 #endif
2199 }
2200
2201 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2202 return os::commit_memory(addr, size, !ExecMem);
2203 }
2204
2205 // If this is a growable mapping, remove the guard pages entirely by
2206 // munmap()ping them. If not, just call uncommit_memory().
2207 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2208 return os::uncommit_memory(addr, size);
2209 }
2210
2211 static address _highest_vm_reserved_address = NULL;
2212
2213 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2214 // at 'requested_addr'. If there are existing memory mappings at the same
2215 // location, however, they will be overwritten. If 'fixed' is false,
2216 // 'requested_addr' is only treated as a hint, the return value may or
2217 // may not start from the requested address. Unlike Bsd mmap(), this
2218 // function returns NULL to indicate failure.
2219 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2220 char * addr;
2221 int flags;
2222
2223 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2224 if (fixed) {
2225 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2226 flags |= MAP_FIXED;
2227 }
2228
2229 // Map reserved/uncommitted pages PROT_NONE so we fail early if we
2230 // touch an uncommitted page. Otherwise, the read/write might
2231 // succeed if we have enough swap space to back the physical page.
2232 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE,
2233 flags, -1, 0);
2234
2235 if (addr != MAP_FAILED) {
2236 // anon_mmap() should only get called during VM initialization,
2237 // don't need lock (actually we can skip locking even it can be called
2238 // from multiple threads, because _highest_vm_reserved_address is just a
2239 // hint about the upper limit of non-stack memory regions.)
2240 if ((address)addr + bytes > _highest_vm_reserved_address) {
2241 _highest_vm_reserved_address = (address)addr + bytes;
2242 }
2243 }
2244
2245 return addr == MAP_FAILED ? NULL : addr;
2246 }
2247
2248 // Don't update _highest_vm_reserved_address, because there might be memory
2249 // regions above addr + size. If so, releasing a memory region only creates
2250 // a hole in the address space, it doesn't help prevent heap-stack collision.
2251 //
2252 static int anon_munmap(char * addr, size_t size) {
2253 return ::munmap(addr, size) == 0;
2254 }
2255
2256 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
2257 size_t alignment_hint) {
2258 return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2259 }
2260
2261 bool os::pd_release_memory(char* addr, size_t size) {
2262 return anon_munmap(addr, size);
2263 }
2264
2265 static bool bsd_mprotect(char* addr, size_t size, int prot) {
2266 // Bsd wants the mprotect address argument to be page aligned.
2267 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size());
2268
2269 // According to SUSv3, mprotect() should only be used with mappings
2270 // established by mmap(), and mmap() always maps whole pages. Unaligned
2271 // 'addr' likely indicates problem in the VM (e.g. trying to change
2272 // protection of malloc'ed or statically allocated memory). Check the
2273 // caller if you hit this assert.
2274 assert(addr == bottom, "sanity check");
2275
2276 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2277 return ::mprotect(bottom, size, prot) == 0;
2278 }
2279
2280 // Set protections specified
2281 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2282 bool is_committed) {
2283 unsigned int p = 0;
2284 switch (prot) {
2285 case MEM_PROT_NONE: p = PROT_NONE; break;
2286 case MEM_PROT_READ: p = PROT_READ; break;
2287 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
2288 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2289 default:
2290 ShouldNotReachHere();
2291 }
2292 // is_committed is unused.
2293 return bsd_mprotect(addr, bytes, p);
2294 }
2295
2296 bool os::guard_memory(char* addr, size_t size) {
2297 return bsd_mprotect(addr, size, PROT_NONE);
2298 }
2299
2300 bool os::unguard_memory(char* addr, size_t size) {
2301 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
2302 }
2303
2304 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
2305 return false;
2306 }
2307
2308 // Large page support
2309
2310 static size_t _large_page_size = 0;
2311
2312 void os::large_page_init() {
2313 }
2314
2315
2316 char* os::reserve_memory_special(size_t bytes, char* req_addr, bool exec) {
2317 // "exec" is passed in but not used. Creating the shared image for
2318 // the code cache doesn't have an SHM_X executable permission to check.
2319 assert(UseLargePages && UseSHM, "only for SHM large pages");
2320
2321 key_t key = IPC_PRIVATE;
2322 char *addr;
2323
2324 bool warn_on_failure = UseLargePages &&
2325 (!FLAG_IS_DEFAULT(UseLargePages) ||
2326 !FLAG_IS_DEFAULT(LargePageSizeInBytes)
2327 );
2328 char msg[128];
2329
2330 // Create a large shared memory region to attach to based on size.
2331 // Currently, size is the total size of the heap
2332 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W);
2333 if (shmid == -1) {
2334 // Possible reasons for shmget failure:
2335 // 1. shmmax is too small for Java heap.
2336 // > check shmmax value: cat /proc/sys/kernel/shmmax
2337 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax
2338 // 2. not enough large page memory.
2339 // > check available large pages: cat /proc/meminfo
2340 // > increase amount of large pages:
2341 // echo new_value > /proc/sys/vm/nr_hugepages
2342 // Note 1: different Bsd may use different name for this property,
2343 // e.g. on Redhat AS-3 it is "hugetlb_pool".
2344 // Note 2: it's possible there's enough physical memory available but
2345 // they are so fragmented after a long run that they can't
2346 // coalesce into large pages. Try to reserve large pages when
2347 // the system is still "fresh".
2348 if (warn_on_failure) {
2349 jio_snprintf(msg, sizeof(msg), "Failed to reserve shared memory (errno = %d).", errno);
2350 warning(msg);
2351 }
2352 return NULL;
2353 }
2354
2355 // attach to the region
2356 addr = (char*)shmat(shmid, req_addr, 0);
2357 int err = errno;
2358
2359 // Remove shmid. If shmat() is successful, the actual shared memory segment
2360 // will be deleted when it's detached by shmdt() or when the process
2361 // terminates. If shmat() is not successful this will remove the shared
2362 // segment immediately.
2363 shmctl(shmid, IPC_RMID, NULL);
2364
2365 if ((intptr_t)addr == -1) {
2366 if (warn_on_failure) {
2367 jio_snprintf(msg, sizeof(msg), "Failed to attach shared memory (errno = %d).", err);
2368 warning(msg);
2369 }
2370 return NULL;
2371 }
2372
2373 // The memory is committed
2374 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, mtNone, CALLER_PC);
2375
2376 return addr;
2377 }
2378
2379 bool os::release_memory_special(char* base, size_t bytes) {
2380 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
2381 // detaching the SHM segment will also delete it, see reserve_memory_special()
2382 int rslt = shmdt(base);
2383 if (rslt == 0) {
2384 tkr.record((address)base, bytes);
2385 return true;
2386 } else {
2387 tkr.discard();
2388 return false;
2389 }
2390
2391 }
2392
2393 size_t os::large_page_size() {
2394 return _large_page_size;
2395 }
2396
2397 // HugeTLBFS allows application to commit large page memory on demand;
2398 // with SysV SHM the entire memory region must be allocated as shared
2399 // memory.
2400 bool os::can_commit_large_page_memory() {
2401 return UseHugeTLBFS;
2402 }
2403
2404 bool os::can_execute_large_page_memory() {
2405 return UseHugeTLBFS;
2406 }
2407
2408 // Reserve memory at an arbitrary address, only if that area is
2409 // available (and not reserved for something else).
2410
2411 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2412 const int max_tries = 10;
2413 char* base[max_tries];
2414 size_t size[max_tries];
2415 const size_t gap = 0x000000;
2416
2417 // Assert only that the size is a multiple of the page size, since
2418 // that's all that mmap requires, and since that's all we really know
2419 // about at this low abstraction level. If we need higher alignment,
2420 // we can either pass an alignment to this method or verify alignment
2421 // in one of the methods further up the call chain. See bug 5044738.
2422 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2423
2424 // Repeatedly allocate blocks until the block is allocated at the
2425 // right spot. Give up after max_tries. Note that reserve_memory() will
2426 // automatically update _highest_vm_reserved_address if the call is
2427 // successful. The variable tracks the highest memory address every reserved
2428 // by JVM. It is used to detect heap-stack collision if running with
2429 // fixed-stack BsdThreads. Because here we may attempt to reserve more
2430 // space than needed, it could confuse the collision detecting code. To
2431 // solve the problem, save current _highest_vm_reserved_address and
2432 // calculate the correct value before return.
2433 address old_highest = _highest_vm_reserved_address;
2434
2435 // Bsd mmap allows caller to pass an address as hint; give it a try first,
2436 // if kernel honors the hint then we can return immediately.
2437 char * addr = anon_mmap(requested_addr, bytes, false);
2438 if (addr == requested_addr) {
2439 return requested_addr;
2440 }
2441
2442 if (addr != NULL) {
2443 // mmap() is successful but it fails to reserve at the requested address
2444 anon_munmap(addr, bytes);
2445 }
2446
2447 int i;
2448 for (i = 0; i < max_tries; ++i) {
2449 base[i] = reserve_memory(bytes);
2450
2451 if (base[i] != NULL) {
2452 // Is this the block we wanted?
2453 if (base[i] == requested_addr) {
2454 size[i] = bytes;
2455 break;
2456 }
2457
2458 // Does this overlap the block we wanted? Give back the overlapped
2459 // parts and try again.
2460
2461 size_t top_overlap = requested_addr + (bytes + gap) - base[i];
2462 if (top_overlap >= 0 && top_overlap < bytes) {
2463 unmap_memory(base[i], top_overlap);
2464 base[i] += top_overlap;
2465 size[i] = bytes - top_overlap;
2466 } else {
2467 size_t bottom_overlap = base[i] + bytes - requested_addr;
2468 if (bottom_overlap >= 0 && bottom_overlap < bytes) {
2469 unmap_memory(requested_addr, bottom_overlap);
2470 size[i] = bytes - bottom_overlap;
2471 } else {
2472 size[i] = bytes;
2473 }
2474 }
2475 }
2476 }
2477
2478 // Give back the unused reserved pieces.
2479
2480 for (int j = 0; j < i; ++j) {
2481 if (base[j] != NULL) {
2482 unmap_memory(base[j], size[j]);
2483 }
2484 }
2485
2486 if (i < max_tries) {
2487 _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes);
2488 return requested_addr;
2489 } else {
2490 _highest_vm_reserved_address = old_highest;
2491 return NULL;
2492 }
2493 }
2494
2495 size_t os::read(int fd, void *buf, unsigned int nBytes) {
2496 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes));
2497 }
2498
2499 // TODO-FIXME: reconcile Solaris' os::sleep with the bsd variation.
2500 // Solaris uses poll(), bsd uses park().
2501 // Poll() is likely a better choice, assuming that Thread.interrupt()
2502 // generates a SIGUSRx signal. Note that SIGUSR1 can interfere with
2503 // SIGSEGV, see 4355769.
2504
2505 int os::sleep(Thread* thread, jlong millis, bool interruptible) {
2506 assert(thread == Thread::current(), "thread consistency check");
2507
2508 ParkEvent * const slp = thread->_SleepEvent ;
2509 slp->reset() ;
2510 OrderAccess::fence() ;
2511
2512 if (interruptible) {
2513 jlong prevtime = javaTimeNanos();
2514
2515 for (;;) {
2516 if (os::is_interrupted(thread, true)) {
2517 return OS_INTRPT;
2518 }
2519
2520 jlong newtime = javaTimeNanos();
2521
2522 if (newtime - prevtime < 0) {
2523 // time moving backwards, should only happen if no monotonic clock
2524 // not a guarantee() because JVM should not abort on kernel/glibc bugs
2525 assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
2526 } else {
2527 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
2528 }
2529
2530 if(millis <= 0) {
2531 return OS_OK;
2532 }
2533
2534 prevtime = newtime;
2535
2536 {
2537 assert(thread->is_Java_thread(), "sanity check");
2538 JavaThread *jt = (JavaThread *) thread;
2539 ThreadBlockInVM tbivm(jt);
2540 OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */);
2541
2542 jt->set_suspend_equivalent();
2543 // cleared by handle_special_suspend_equivalent_condition() or
2544 // java_suspend_self() via check_and_wait_while_suspended()
2545
2546 slp->park(millis);
2547
2548 // were we externally suspended while we were waiting?
2549 jt->check_and_wait_while_suspended();
2550 }
2551 }
2552 } else {
2553 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
2554 jlong prevtime = javaTimeNanos();
2555
2556 for (;;) {
2557 // It'd be nice to avoid the back-to-back javaTimeNanos() calls on
2558 // the 1st iteration ...
2559 jlong newtime = javaTimeNanos();
2560
2561 if (newtime - prevtime < 0) {
2562 // time moving backwards, should only happen if no monotonic clock
2563 // not a guarantee() because JVM should not abort on kernel/glibc bugs
2564 assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
2565 } else {
2566 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
2567 }
2568
2569 if(millis <= 0) break ;
2570
2571 prevtime = newtime;
2572 slp->park(millis);
2573 }
2574 return OS_OK ;
2575 }
2576 }
2577
2578 int os::naked_sleep() {
2579 // %% make the sleep time an integer flag. for now use 1 millisec.
2580 return os::sleep(Thread::current(), 1, false);
2581 }
2582
2583 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2584 void os::infinite_sleep() {
2585 while (true) { // sleep forever ...
2586 ::sleep(100); // ... 100 seconds at a time
2587 }
2588 }
2589
2590 // Used to convert frequent JVM_Yield() to nops
2591 bool os::dont_yield() {
2592 return DontYieldALot;
2593 }
2594
2595 void os::yield() {
2596 sched_yield();
2597 }
2598
2599 os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;}
2600
2601 void os::yield_all(int attempts) {
2602 // Yields to all threads, including threads with lower priorities
2603 // Threads on Bsd are all with same priority. The Solaris style
2604 // os::yield_all() with nanosleep(1ms) is not necessary.
2605 sched_yield();
2606 }
2607
2608 // Called from the tight loops to possibly influence time-sharing heuristics
2609 void os::loop_breaker(int attempts) {
2610 os::yield_all(attempts);
2611 }
2612
2613 ////////////////////////////////////////////////////////////////////////////////
2614 // thread priority support
2615
2616 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2617 // only supports dynamic priority, static priority must be zero. For real-time
2618 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
2619 // However, for large multi-threaded applications, SCHED_RR is not only slower
2620 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2621 // of 5 runs - Sep 2005).
2622 //
2623 // The following code actually changes the niceness of kernel-thread/LWP. It
2624 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
2625 // not the entire user process, and user level threads are 1:1 mapped to kernel
2626 // threads. It has always been the case, but could change in the future. For
2627 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2628 // It is only used when ThreadPriorityPolicy=1 and requires root privilege.
2629
2630 #if !defined(__APPLE__)
2631 int os::java_to_os_priority[CriticalPriority + 1] = {
2632 19, // 0 Entry should never be used
2633
2634 0, // 1 MinPriority
2635 3, // 2
2636 6, // 3
2637
2638 10, // 4
2639 15, // 5 NormPriority
2640 18, // 6
2641
2642 21, // 7
2643 25, // 8
2644 28, // 9 NearMaxPriority
2645
2646 31, // 10 MaxPriority
2647
2648 31 // 11 CriticalPriority
2649 };
2650 #else
2651 /* Using Mach high-level priority assignments */
2652 int os::java_to_os_priority[CriticalPriority + 1] = {
2653 0, // 0 Entry should never be used (MINPRI_USER)
2654
2655 27, // 1 MinPriority
2656 28, // 2
2657 29, // 3
2658
2659 30, // 4
2660 31, // 5 NormPriority (BASEPRI_DEFAULT)
2661 32, // 6
2662
2663 33, // 7
2664 34, // 8
2665 35, // 9 NearMaxPriority
2666
2667 36, // 10 MaxPriority
2668
2669 36 // 11 CriticalPriority
2670 };
2671 #endif
2672
2673 static int prio_init() {
2674 if (ThreadPriorityPolicy == 1) {
2675 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1
2676 // if effective uid is not root. Perhaps, a more elegant way of doing
2677 // this is to test CAP_SYS_NICE capability, but that will require libcap.so
2678 if (geteuid() != 0) {
2679 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
2680 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd");
2681 }
2682 ThreadPriorityPolicy = 0;
2683 }
2684 }
2685 if (UseCriticalJavaThreadPriority) {
2686 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2687 }
2688 return 0;
2689 }
2690
2691 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2692 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) return OS_OK;
2693
2694 #ifdef __OpenBSD__
2695 // OpenBSD pthread_setprio starves low priority threads
2696 return OS_OK;
2697 #elif defined(__FreeBSD__)
2698 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2699 #elif defined(__APPLE__) || defined(__NetBSD__)
2700 struct sched_param sp;
2701 int policy;
2702 pthread_t self = pthread_self();
2703
2704 if (pthread_getschedparam(self, &policy, &sp) != 0)
2705 return OS_ERR;
2706
2707 sp.sched_priority = newpri;
2708 if (pthread_setschedparam(self, policy, &sp) != 0)
2709 return OS_ERR;
2710
2711 return OS_OK;
2712 #else
2713 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2714 return (ret == 0) ? OS_OK : OS_ERR;
2715 #endif
2716 }
2717
2718 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2719 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) {
2720 *priority_ptr = java_to_os_priority[NormPriority];
2721 return OS_OK;
2722 }
2723
2724 errno = 0;
2725 #if defined(__OpenBSD__) || defined(__FreeBSD__)
2726 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2727 #elif defined(__APPLE__) || defined(__NetBSD__)
2728 int policy;
2729 struct sched_param sp;
2730
2731 pthread_getschedparam(pthread_self(), &policy, &sp);
2732 *priority_ptr = sp.sched_priority;
2733 #else
2734 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2735 #endif
2736 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2737 }
2738
2739 // Hint to the underlying OS that a task switch would not be good.
2740 // Void return because it's a hint and can fail.
2741 void os::hint_no_preempt() {}
2742
2743 ////////////////////////////////////////////////////////////////////////////////
2744 // suspend/resume support
2745
2746 // the low-level signal-based suspend/resume support is a remnant from the
2747 // old VM-suspension that used to be for java-suspension, safepoints etc,
2748 // within hotspot. Now there is a single use-case for this:
2749 // - calling get_thread_pc() on the VMThread by the flat-profiler task
2750 // that runs in the watcher thread.
2751 // The remaining code is greatly simplified from the more general suspension
2752 // code that used to be used.
2753 //
2754 // The protocol is quite simple:
2755 // - suspend:
2756 // - sends a signal to the target thread
2757 // - polls the suspend state of the osthread using a yield loop
2758 // - target thread signal handler (SR_handler) sets suspend state
2759 // and blocks in sigsuspend until continued
2760 // - resume:
2761 // - sets target osthread state to continue
2762 // - sends signal to end the sigsuspend loop in the SR_handler
2763 //
2764 // Note that the SR_lock plays no role in this suspend/resume protocol.
2765 //
2766
2767 static void resume_clear_context(OSThread *osthread) {
2768 osthread->set_ucontext(NULL);
2769 osthread->set_siginfo(NULL);
2770 }
2771
2772 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2773 osthread->set_ucontext(context);
2774 osthread->set_siginfo(siginfo);
2775 }
2776
2777 //
2778 // Handler function invoked when a thread's execution is suspended or
2779 // resumed. We have to be careful that only async-safe functions are
2780 // called here (Note: most pthread functions are not async safe and
2781 // should be avoided.)
2782 //
2783 // Note: sigwait() is a more natural fit than sigsuspend() from an
2784 // interface point of view, but sigwait() prevents the signal hander
2785 // from being run. libpthread would get very confused by not having
2786 // its signal handlers run and prevents sigwait()'s use with the
2787 // mutex granting granting signal.
2788 //
2789 // Currently only ever called on the VMThread or JavaThread
2790 //
2791 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2792 // Save and restore errno to avoid confusing native code with EINTR
2793 // after sigsuspend.
2794 int old_errno = errno;
2795
2796 Thread* thread = Thread::current();
2797 OSThread* osthread = thread->osthread();
2798 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
2799
2800 os::SuspendResume::State current = osthread->sr.state();
2801 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
2802 suspend_save_context(osthread, siginfo, context);
2803
2804 // attempt to switch the state, we assume we had a SUSPEND_REQUEST
2805 os::SuspendResume::State state = osthread->sr.suspended();
2806 if (state == os::SuspendResume::SR_SUSPENDED) {
2807 sigset_t suspend_set; // signals for sigsuspend()
2808
2809 // get current set of blocked signals and unblock resume signal
2810 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2811 sigdelset(&suspend_set, SR_signum);
2812
2813 sr_semaphore.signal();
2814 // wait here until we are resumed
2815 while (1) {
2816 sigsuspend(&suspend_set);
2817
2818 os::SuspendResume::State result = osthread->sr.running();
2819 if (result == os::SuspendResume::SR_RUNNING) {
2820 sr_semaphore.signal();
2821 break;
2822 } else if (result != os::SuspendResume::SR_SUSPENDED) {
2823 ShouldNotReachHere();
2824 }
2825 }
2826
2827 } else if (state == os::SuspendResume::SR_RUNNING) {
2828 // request was cancelled, continue
2829 } else {
2830 ShouldNotReachHere();
2831 }
2832
2833 resume_clear_context(osthread);
2834 } else if (current == os::SuspendResume::SR_RUNNING) {
2835 // request was cancelled, continue
2836 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
2837 // ignore
2838 } else {
2839 // ignore
2840 }
2841
2842 errno = old_errno;
2843 }
2844
2845
2846 static int SR_initialize() {
2847 struct sigaction act;
2848 char *s;
2849 /* Get signal number to use for suspend/resume */
2850 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2851 int sig = ::strtol(s, 0, 10);
2852 if (sig > 0 || sig < NSIG) {
2853 SR_signum = sig;
2854 }
2855 }
2856
2857 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2858 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2859
2860 sigemptyset(&SR_sigset);
2861 sigaddset(&SR_sigset, SR_signum);
2862
2863 /* Set up signal handler for suspend/resume */
2864 act.sa_flags = SA_RESTART|SA_SIGINFO;
2865 act.sa_handler = (void (*)(int)) SR_handler;
2866
2867 // SR_signum is blocked by default.
2868 // 4528190 - We also need to block pthread restart signal (32 on all
2869 // supported Bsd platforms). Note that BsdThreads need to block
2870 // this signal for all threads to work properly. So we don't have
2871 // to use hard-coded signal number when setting up the mask.
2872 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2873
2874 if (sigaction(SR_signum, &act, 0) == -1) {
2875 return -1;
2876 }
2877
2878 // Save signal flag
2879 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2880 return 0;
2881 }
2882
2883 static int sr_notify(OSThread* osthread) {
2884 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2885 assert_status(status == 0, status, "pthread_kill");
2886 return status;
2887 }
2888
2889 // "Randomly" selected value for how long we want to spin
2890 // before bailing out on suspending a thread, also how often
2891 // we send a signal to a thread we want to resume
2892 static const int RANDOMLY_LARGE_INTEGER = 1000000;
2893 static const int RANDOMLY_LARGE_INTEGER2 = 100;
2894
2895 // returns true on success and false on error - really an error is fatal
2896 // but this seems the normal response to library errors
2897 static bool do_suspend(OSThread* osthread) {
2898 assert(osthread->sr.is_running(), "thread should be running");
2899 assert(!sr_semaphore.trywait(), "semaphore has invalid state");
2900
2901 // mark as suspended and send signal
2902 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
2903 // failed to switch, state wasn't running?
2904 ShouldNotReachHere();
2905 return false;
2906 }
2907
2908 if (sr_notify(osthread) != 0) {
2909 ShouldNotReachHere();
2910 }
2911
2912 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
2913 while (true) {
2914 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2915 break;
2916 } else {
2917 // timeout
2918 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
2919 if (cancelled == os::SuspendResume::SR_RUNNING) {
2920 return false;
2921 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
2922 // make sure that we consume the signal on the semaphore as well
2923 sr_semaphore.wait();
2924 break;
2925 } else {
2926 ShouldNotReachHere();
2927 return false;
2928 }
2929 }
2930 }
2931
2932 guarantee(osthread->sr.is_suspended(), "Must be suspended");
2933 return true;
2934 }
2935
2936 static void do_resume(OSThread* osthread) {
2937 assert(osthread->sr.is_suspended(), "thread should be suspended");
2938 assert(!sr_semaphore.trywait(), "invalid semaphore state");
2939
2940 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
2941 // failed to switch to WAKEUP_REQUEST
2942 ShouldNotReachHere();
2943 return;
2944 }
2945
2946 while (true) {
2947 if (sr_notify(osthread) == 0) {
2948 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2949 if (osthread->sr.is_running()) {
2950 return;
2951 }
2952 }
2953 } else {
2954 ShouldNotReachHere();
2955 }
2956 }
2957
2958 guarantee(osthread->sr.is_running(), "Must be running!");
2959 }
2960
2961 ////////////////////////////////////////////////////////////////////////////////
2962 // interrupt support
2963
2964 void os::interrupt(Thread* thread) {
2965 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
2966 "possibility of dangling Thread pointer");
2967
2968 OSThread* osthread = thread->osthread();
2969
2970 if (!osthread->interrupted()) {
2971 osthread->set_interrupted(true);
2972 // More than one thread can get here with the same value of osthread,
2973 // resulting in multiple notifications. We do, however, want the store
2974 // to interrupted() to be visible to other threads before we execute unpark().
2975 OrderAccess::fence();
2976 ParkEvent * const slp = thread->_SleepEvent ;
2977 if (slp != NULL) slp->unpark() ;
2978 }
2979
2980 // For JSR166. Unpark even if interrupt status already was set
2981 if (thread->is_Java_thread())
2982 ((JavaThread*)thread)->parker()->unpark();
2983
2984 ParkEvent * ev = thread->_ParkEvent ;
2985 if (ev != NULL) ev->unpark() ;
2986
2987 }
2988
2989 bool os::is_interrupted(Thread* thread, bool clear_interrupted) {
2990 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
2991 "possibility of dangling Thread pointer");
2992
2993 OSThread* osthread = thread->osthread();
2994
2995 bool interrupted = osthread->interrupted();
2996
2997 if (interrupted && clear_interrupted) {
2998 osthread->set_interrupted(false);
2999 // consider thread->_SleepEvent->reset() ... optional optimization
3000 }
3001
3002 return interrupted;
3003 }
3004
3005 ///////////////////////////////////////////////////////////////////////////////////
3006 // signal handling (except suspend/resume)
3007
3008 // This routine may be used by user applications as a "hook" to catch signals.
3009 // The user-defined signal handler must pass unrecognized signals to this
3010 // routine, and if it returns true (non-zero), then the signal handler must
3011 // return immediately. If the flag "abort_if_unrecognized" is true, then this
3012 // routine will never retun false (zero), but instead will execute a VM panic
3013 // routine kill the process.
3014 //
3015 // If this routine returns false, it is OK to call it again. This allows
3016 // the user-defined signal handler to perform checks either before or after
3017 // the VM performs its own checks. Naturally, the user code would be making
3018 // a serious error if it tried to handle an exception (such as a null check
3019 // or breakpoint) that the VM was generating for its own correct operation.
3020 //
3021 // This routine may recognize any of the following kinds of signals:
3022 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
3023 // It should be consulted by handlers for any of those signals.
3024 //
3025 // The caller of this routine must pass in the three arguments supplied
3026 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
3027 // field of the structure passed to sigaction(). This routine assumes that
3028 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
3029 //
3030 // Note that the VM will print warnings if it detects conflicting signal
3031 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
3032 //
3033 extern "C" JNIEXPORT int
3034 JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
3035 void* ucontext, int abort_if_unrecognized);
3036
3037 void signalHandler(int sig, siginfo_t* info, void* uc) {
3038 assert(info != NULL && uc != NULL, "it must be old kernel");
3039 int orig_errno = errno; // Preserve errno value over signal handler.
3040 JVM_handle_bsd_signal(sig, info, uc, true);
3041 errno = orig_errno;
3042 }
3043
3044
3045 // This boolean allows users to forward their own non-matching signals
3046 // to JVM_handle_bsd_signal, harmlessly.
3047 bool os::Bsd::signal_handlers_are_installed = false;
3048
3049 // For signal-chaining
3050 struct sigaction os::Bsd::sigact[MAXSIGNUM];
3051 unsigned int os::Bsd::sigs = 0;
3052 bool os::Bsd::libjsig_is_loaded = false;
3053 typedef struct sigaction *(*get_signal_t)(int);
3054 get_signal_t os::Bsd::get_signal_action = NULL;
3055
3056 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
3057 struct sigaction *actp = NULL;
3058
3059 if (libjsig_is_loaded) {
3060 // Retrieve the old signal handler from libjsig
3061 actp = (*get_signal_action)(sig);
3062 }
3063 if (actp == NULL) {
3064 // Retrieve the preinstalled signal handler from jvm
3065 actp = get_preinstalled_handler(sig);
3066 }
3067
3068 return actp;
3069 }
3070
3071 static bool call_chained_handler(struct sigaction *actp, int sig,
3072 siginfo_t *siginfo, void *context) {
3073 // Call the old signal handler
3074 if (actp->sa_handler == SIG_DFL) {
3075 // It's more reasonable to let jvm treat it as an unexpected exception
3076 // instead of taking the default action.
3077 return false;
3078 } else if (actp->sa_handler != SIG_IGN) {
3079 if ((actp->sa_flags & SA_NODEFER) == 0) {
3080 // automaticlly block the signal
3081 sigaddset(&(actp->sa_mask), sig);
3082 }
3083
3084 sa_handler_t hand;
3085 sa_sigaction_t sa;
3086 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
3087 // retrieve the chained handler
3088 if (siginfo_flag_set) {
3089 sa = actp->sa_sigaction;
3090 } else {
3091 hand = actp->sa_handler;
3092 }
3093
3094 if ((actp->sa_flags & SA_RESETHAND) != 0) {
3095 actp->sa_handler = SIG_DFL;
3096 }
3097
3098 // try to honor the signal mask
3099 sigset_t oset;
3100 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
3101
3102 // call into the chained handler
3103 if (siginfo_flag_set) {
3104 (*sa)(sig, siginfo, context);
3105 } else {
3106 (*hand)(sig);
3107 }
3108
3109 // restore the signal mask
3110 pthread_sigmask(SIG_SETMASK, &oset, 0);
3111 }
3112 // Tell jvm's signal handler the signal is taken care of.
3113 return true;
3114 }
3115
3116 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
3117 bool chained = false;
3118 // signal-chaining
3119 if (UseSignalChaining) {
3120 struct sigaction *actp = get_chained_signal_action(sig);
3121 if (actp != NULL) {
3122 chained = call_chained_handler(actp, sig, siginfo, context);
3123 }
3124 }
3125 return chained;
3126 }
3127
3128 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) {
3129 if ((( (unsigned int)1 << sig ) & sigs) != 0) {
3130 return &sigact[sig];
3131 }
3132 return NULL;
3133 }
3134
3135 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
3136 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3137 sigact[sig] = oldAct;
3138 sigs |= (unsigned int)1 << sig;
3139 }
3140
3141 // for diagnostic
3142 int os::Bsd::sigflags[MAXSIGNUM];
3143
3144 int os::Bsd::get_our_sigflags(int sig) {
3145 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3146 return sigflags[sig];
3147 }
3148
3149 void os::Bsd::set_our_sigflags(int sig, int flags) {
3150 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3151 sigflags[sig] = flags;
3152 }
3153
3154 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
3155 // Check for overwrite.
3156 struct sigaction oldAct;
3157 sigaction(sig, (struct sigaction*)NULL, &oldAct);
3158
3159 void* oldhand = oldAct.sa_sigaction
3160 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3161 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3162 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
3163 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
3164 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
3165 if (AllowUserSignalHandlers || !set_installed) {
3166 // Do not overwrite; user takes responsibility to forward to us.
3167 return;
3168 } else if (UseSignalChaining) {
3169 // save the old handler in jvm
3170 save_preinstalled_handler(sig, oldAct);
3171 // libjsig also interposes the sigaction() call below and saves the
3172 // old sigaction on it own.
3173 } else {
3174 fatal(err_msg("Encountered unexpected pre-existing sigaction handler "
3175 "%#lx for signal %d.", (long)oldhand, sig));
3176 }
3177 }
3178
3179 struct sigaction sigAct;
3180 sigfillset(&(sigAct.sa_mask));
3181 sigAct.sa_handler = SIG_DFL;
3182 if (!set_installed) {
3183 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3184 } else {
3185 sigAct.sa_sigaction = signalHandler;
3186 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3187 }
3188 #if __APPLE__
3189 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV
3190 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages"
3191 // if the signal handler declares it will handle it on alternate stack.
3192 // Notice we only declare we will handle it on alt stack, but we are not
3193 // actually going to use real alt stack - this is just a workaround.
3194 // Please see ux_exception.c, method catch_mach_exception_raise for details
3195 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c
3196 if (sig == SIGSEGV) {
3197 sigAct.sa_flags |= SA_ONSTACK;
3198 }
3199 #endif
3200
3201 // Save flags, which are set by ours
3202 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3203 sigflags[sig] = sigAct.sa_flags;
3204
3205 int ret = sigaction(sig, &sigAct, &oldAct);
3206 assert(ret == 0, "check");
3207
3208 void* oldhand2 = oldAct.sa_sigaction
3209 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3210 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3211 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
3212 }
3213
3214 // install signal handlers for signals that HotSpot needs to
3215 // handle in order to support Java-level exception handling.
3216
3217 void os::Bsd::install_signal_handlers() {
3218 if (!signal_handlers_are_installed) {
3219 signal_handlers_are_installed = true;
3220
3221 // signal-chaining
3222 typedef void (*signal_setting_t)();
3223 signal_setting_t begin_signal_setting = NULL;
3224 signal_setting_t end_signal_setting = NULL;
3225 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3226 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
3227 if (begin_signal_setting != NULL) {
3228 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3229 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
3230 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
3231 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
3232 libjsig_is_loaded = true;
3233 assert(UseSignalChaining, "should enable signal-chaining");
3234 }
3235 if (libjsig_is_loaded) {
3236 // Tell libjsig jvm is setting signal handlers
3237 (*begin_signal_setting)();
3238 }
3239
3240 set_signal_handler(SIGSEGV, true);
3241 set_signal_handler(SIGPIPE, true);
3242 set_signal_handler(SIGBUS, true);
3243 set_signal_handler(SIGILL, true);
3244 set_signal_handler(SIGFPE, true);
3245 set_signal_handler(SIGXFSZ, true);
3246
3247 #if defined(__APPLE__)
3248 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
3249 // signals caught and handled by the JVM. To work around this, we reset the mach task
3250 // signal handler that's placed on our process by CrashReporter. This disables
3251 // CrashReporter-based reporting.
3252 //
3253 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
3254 // on caught fatal signals.
3255 //
3256 // Additionally, gdb installs both standard BSD signal handlers, and mach exception
3257 // handlers. By replacing the existing task exception handler, we disable gdb's mach
3258 // exception handling, while leaving the standard BSD signal handlers functional.
3259 kern_return_t kr;
3260 kr = task_set_exception_ports(mach_task_self(),
3261 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
3262 MACH_PORT_NULL,
3263 EXCEPTION_STATE_IDENTITY,
3264 MACHINE_THREAD_STATE);
3265
3266 assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
3267 #endif
3268
3269 if (libjsig_is_loaded) {
3270 // Tell libjsig jvm finishes setting signal handlers
3271 (*end_signal_setting)();
3272 }
3273
3274 // We don't activate signal checker if libjsig is in place, we trust ourselves
3275 // and if UserSignalHandler is installed all bets are off
3276 if (CheckJNICalls) {
3277 if (libjsig_is_loaded) {
3278 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
3279 check_signals = false;
3280 }
3281 if (AllowUserSignalHandlers) {
3282 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
3283 check_signals = false;
3284 }
3285 }
3286 }
3287 }
3288
3289
3290 /////
3291 // glibc on Bsd platform uses non-documented flag
3292 // to indicate, that some special sort of signal
3293 // trampoline is used.
3294 // We will never set this flag, and we should
3295 // ignore this flag in our diagnostic
3296 #ifdef SIGNIFICANT_SIGNAL_MASK
3297 #undef SIGNIFICANT_SIGNAL_MASK
3298 #endif
3299 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
3300
3301 static const char* get_signal_handler_name(address handler,
3302 char* buf, int buflen) {
3303 int offset;
3304 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
3305 if (found) {
3306 // skip directory names
3307 const char *p1, *p2;
3308 p1 = buf;
3309 size_t len = strlen(os::file_separator());
3310 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
3311 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
3312 } else {
3313 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
3314 }
3315 return buf;
3316 }
3317
3318 static void print_signal_handler(outputStream* st, int sig,
3319 char* buf, size_t buflen) {
3320 struct sigaction sa;
3321
3322 sigaction(sig, NULL, &sa);
3323
3324 // See comment for SIGNIFICANT_SIGNAL_MASK define
3325 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3326
3327 st->print("%s: ", os::exception_name(sig, buf, buflen));
3328
3329 address handler = (sa.sa_flags & SA_SIGINFO)
3330 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
3331 : CAST_FROM_FN_PTR(address, sa.sa_handler);
3332
3333 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
3334 st->print("SIG_DFL");
3335 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
3336 st->print("SIG_IGN");
3337 } else {
3338 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
3339 }
3340
3341 st->print(", sa_mask[0]=" PTR32_FORMAT, *(uint32_t*)&sa.sa_mask);
3342
3343 address rh = VMError::get_resetted_sighandler(sig);
3344 // May be, handler was resetted by VMError?
3345 if(rh != NULL) {
3346 handler = rh;
3347 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
3348 }
3349
3350 st->print(", sa_flags=" PTR32_FORMAT, sa.sa_flags);
3351
3352 // Check: is it our handler?
3353 if(handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
3354 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
3355 // It is our signal handler
3356 // check for flags, reset system-used one!
3357 if((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3358 st->print(
3359 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
3360 os::Bsd::get_our_sigflags(sig));
3361 }
3362 }
3363 st->cr();
3364 }
3365
3366
3367 #define DO_SIGNAL_CHECK(sig) \
3368 if (!sigismember(&check_signal_done, sig)) \
3369 os::Bsd::check_signal_handler(sig)
3370
3371 // This method is a periodic task to check for misbehaving JNI applications
3372 // under CheckJNI, we can add any periodic checks here
3373
3374 void os::run_periodic_checks() {
3375
3376 if (check_signals == false) return;
3377
3378 // SEGV and BUS if overridden could potentially prevent
3379 // generation of hs*.log in the event of a crash, debugging
3380 // such a case can be very challenging, so we absolutely
3381 // check the following for a good measure:
3382 DO_SIGNAL_CHECK(SIGSEGV);
3383 DO_SIGNAL_CHECK(SIGILL);
3384 DO_SIGNAL_CHECK(SIGFPE);
3385 DO_SIGNAL_CHECK(SIGBUS);
3386 DO_SIGNAL_CHECK(SIGPIPE);
3387 DO_SIGNAL_CHECK(SIGXFSZ);
3388
3389
3390 // ReduceSignalUsage allows the user to override these handlers
3391 // see comments at the very top and jvm_solaris.h
3392 if (!ReduceSignalUsage) {
3393 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
3394 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
3395 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
3396 DO_SIGNAL_CHECK(BREAK_SIGNAL);
3397 }
3398
3399 DO_SIGNAL_CHECK(SR_signum);
3400 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL);
3401 }
3402
3403 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
3404
3405 static os_sigaction_t os_sigaction = NULL;
3406
3407 void os::Bsd::check_signal_handler(int sig) {
3408 char buf[O_BUFLEN];
3409 address jvmHandler = NULL;
3410
3411
3412 struct sigaction act;
3413 if (os_sigaction == NULL) {
3414 // only trust the default sigaction, in case it has been interposed
3415 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
3416 if (os_sigaction == NULL) return;
3417 }
3418
3419 os_sigaction(sig, (struct sigaction*)NULL, &act);
3420
3421
3422 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3423
3424 address thisHandler = (act.sa_flags & SA_SIGINFO)
3425 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3426 : CAST_FROM_FN_PTR(address, act.sa_handler) ;
3427
3428
3429 switch(sig) {
3430 case SIGSEGV:
3431 case SIGBUS:
3432 case SIGFPE:
3433 case SIGPIPE:
3434 case SIGILL:
3435 case SIGXFSZ:
3436 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
3437 break;
3438
3439 case SHUTDOWN1_SIGNAL:
3440 case SHUTDOWN2_SIGNAL:
3441 case SHUTDOWN3_SIGNAL:
3442 case BREAK_SIGNAL:
3443 jvmHandler = (address)user_handler();
3444 break;
3445
3446 case INTERRUPT_SIGNAL:
3447 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL);
3448 break;
3449
3450 default:
3451 if (sig == SR_signum) {
3452 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3453 } else {
3454 return;
3455 }
3456 break;
3457 }
3458
3459 if (thisHandler != jvmHandler) {
3460 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3461 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3462 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3463 // No need to check this sig any longer
3464 sigaddset(&check_signal_done, sig);
3465 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3466 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3467 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig));
3468 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags);
3469 // No need to check this sig any longer
3470 sigaddset(&check_signal_done, sig);
3471 }
3472
3473 // Dump all the signal
3474 if (sigismember(&check_signal_done, sig)) {
3475 print_signal_handlers(tty, buf, O_BUFLEN);
3476 }
3477 }
3478
3479 extern void report_error(char* file_name, int line_no, char* title, char* format, ...);
3480
3481 extern bool signal_name(int signo, char* buf, size_t len);
3482
3483 const char* os::exception_name(int exception_code, char* buf, size_t size) {
3484 if (0 < exception_code && exception_code <= SIGRTMAX) {
3485 // signal
3486 if (!signal_name(exception_code, buf, size)) {
3487 jio_snprintf(buf, size, "SIG%d", exception_code);
3488 }
3489 return buf;
3490 } else {
3491 return NULL;
3492 }
3493 }
3494
3495 // this is called _before_ the most of global arguments have been parsed
3496 void os::init(void) {
3497 char dummy; /* used to get a guess on initial stack address */
3498 // first_hrtime = gethrtime();
3499
3500 // With BsdThreads the JavaMain thread pid (primordial thread)
3501 // is different than the pid of the java launcher thread.
3502 // So, on Bsd, the launcher thread pid is passed to the VM
3503 // via the sun.java.launcher.pid property.
3504 // Use this property instead of getpid() if it was correctly passed.
3505 // See bug 6351349.
3506 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid();
3507
3508 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid();
3509
3510 clock_tics_per_sec = CLK_TCK;
3511
3512 init_random(1234567);
3513
3514 ThreadCritical::initialize();
3515
3516 Bsd::set_page_size(getpagesize());
3517 if (Bsd::page_size() == -1) {
3518 fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)",
3519 strerror(errno)));
3520 }
3521 init_page_sizes((size_t) Bsd::page_size());
3522
3523 Bsd::initialize_system_info();
3524
3525 // main_thread points to the aboriginal thread
3526 Bsd::_main_thread = pthread_self();
3527
3528 Bsd::clock_init();
3529 initial_time_count = os::elapsed_counter();
3530
3531 #ifdef __APPLE__
3532 // XXXDARWIN
3533 // Work around the unaligned VM callbacks in hotspot's
3534 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on
3535 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces
3536 // alignment when doing symbol lookup. To work around this, we force early
3537 // binding of all symbols now, thus binding when alignment is known-good.
3538 _dyld_bind_fully_image_containing_address((const void *) &os::init);
3539 #endif
3540 }
3541
3542 // To install functions for atexit system call
3543 extern "C" {
3544 static void perfMemory_exit_helper() {
3545 perfMemory_exit();
3546 }
3547 }
3548
3549 // this is called _after_ the global arguments have been parsed
3550 jint os::init_2(void)
3551 {
3552 // Allocate a single page and mark it as readable for safepoint polling
3553 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3554 guarantee( polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page" );
3555
3556 os::set_polling_page( polling_page );
3557
3558 #ifndef PRODUCT
3559 if(Verbose && PrintMiscellaneous)
3560 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page);
3561 #endif
3562
3563 if (!UseMembar) {
3564 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3565 guarantee( mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page");
3566 os::set_memory_serialize_page( mem_serialize_page );
3567
3568 #ifndef PRODUCT
3569 if(Verbose && PrintMiscellaneous)
3570 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page);
3571 #endif
3572 }
3573
3574 os::large_page_init();
3575
3576 // initialize suspend/resume support - must do this before signal_sets_init()
3577 if (SR_initialize() != 0) {
3578 perror("SR_initialize failed");
3579 return JNI_ERR;
3580 }
3581
3582 Bsd::signal_sets_init();
3583 Bsd::install_signal_handlers();
3584
3585 // Check minimum allowable stack size for thread creation and to initialize
3586 // the java system classes, including StackOverflowError - depends on page
3587 // size. Add a page for compiler2 recursion in main thread.
3588 // Add in 2*BytesPerWord times page size to account for VM stack during
3589 // class initialization depending on 32 or 64 bit VM.
3590 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed,
3591 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+
3592 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size());
3593
3594 size_t threadStackSizeInBytes = ThreadStackSize * K;
3595 if (threadStackSizeInBytes != 0 &&
3596 threadStackSizeInBytes < os::Bsd::min_stack_allowed) {
3597 tty->print_cr("\nThe stack size specified is too small, "
3598 "Specify at least %dk",
3599 os::Bsd::min_stack_allowed/ K);
3600 return JNI_ERR;
3601 }
3602
3603 // Make the stack size a multiple of the page size so that
3604 // the yellow/red zones can be guarded.
3605 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes,
3606 vm_page_size()));
3607
3608 if (MaxFDLimit) {
3609 // set the number of file descriptors to max. print out error
3610 // if getrlimit/setrlimit fails but continue regardless.
3611 struct rlimit nbr_files;
3612 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3613 if (status != 0) {
3614 if (PrintMiscellaneous && (Verbose || WizardMode))
3615 perror("os::init_2 getrlimit failed");
3616 } else {
3617 nbr_files.rlim_cur = nbr_files.rlim_max;
3618
3619 #ifdef __APPLE__
3620 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3621 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3622 // be used instead
3623 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3624 #endif
3625
3626 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3627 if (status != 0) {
3628 if (PrintMiscellaneous && (Verbose || WizardMode))
3629 perror("os::init_2 setrlimit failed");
3630 }
3631 }
3632 }
3633
3634 // at-exit methods are called in the reverse order of their registration.
3635 // atexit functions are called on return from main or as a result of a
3636 // call to exit(3C). There can be only 32 of these functions registered
3637 // and atexit() does not set errno.
3638
3639 if (PerfAllowAtExitRegistration) {
3640 // only register atexit functions if PerfAllowAtExitRegistration is set.
3641 // atexit functions can be delayed until process exit time, which
3642 // can be problematic for embedded VM situations. Embedded VMs should
3643 // call DestroyJavaVM() to assure that VM resources are released.
3644
3645 // note: perfMemory_exit_helper atexit function may be removed in
3646 // the future if the appropriate cleanup code can be added to the
3647 // VM_Exit VMOperation's doit method.
3648 if (atexit(perfMemory_exit_helper) != 0) {
3649 warning("os::init2 atexit(perfMemory_exit_helper) failed");
3650 }
3651 }
3652
3653 // initialize thread priority policy
3654 prio_init();
3655
3656 #ifdef __APPLE__
3657 // dynamically link to objective c gc registration
3658 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3659 if (handleLibObjc != NULL) {
3660 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3661 }
3662 #endif
3663
3664 return JNI_OK;
3665 }
3666
3667 // this is called at the end of vm_initialization
3668 void os::init_3(void) { }
3669
3670 // Mark the polling page as unreadable
3671 void os::make_polling_page_unreadable(void) {
3672 if( !guard_memory((char*)_polling_page, Bsd::page_size()) )
3673 fatal("Could not disable polling page");
3674 };
3675
3676 // Mark the polling page as readable
3677 void os::make_polling_page_readable(void) {
3678 if( !bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
3679 fatal("Could not enable polling page");
3680 }
3681 };
3682
3683 int os::active_processor_count() {
3684 return _processor_count;
3685 }
3686
3687 void os::set_native_thread_name(const char *name) {
3688 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3689 // This is only supported in Snow Leopard and beyond
3690 if (name != NULL) {
3691 // Add a "Java: " prefix to the name
3692 char buf[MAXTHREADNAMESIZE];
3693 snprintf(buf, sizeof(buf), "Java: %s", name);
3694 pthread_setname_np(buf);
3695 }
3696 #endif
3697 }
3698
3699 bool os::distribute_processes(uint length, uint* distribution) {
3700 // Not yet implemented.
3701 return false;
3702 }
3703
3704 bool os::bind_to_processor(uint processor_id) {
3705 // Not yet implemented.
3706 return false;
3707 }
3708
3709 void os::SuspendedThreadTask::internal_do_task() {
3710 if (do_suspend(_thread->osthread())) {
3711 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
3712 do_task(context);
3713 do_resume(_thread->osthread());
3714 }
3715 }
3716
3717 ///
3718 class PcFetcher : public os::SuspendedThreadTask {
3719 public:
3720 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {}
3721 ExtendedPC result();
3722 protected:
3723 void do_task(const os::SuspendedThreadTaskContext& context);
3724 private:
3725 ExtendedPC _epc;
3726 };
3727
3728 ExtendedPC PcFetcher::result() {
3729 guarantee(is_done(), "task is not done yet.");
3730 return _epc;
3731 }
3732
3733 void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) {
3734 Thread* thread = context.thread();
3735 OSThread* osthread = thread->osthread();
3736 if (osthread->ucontext() != NULL) {
3737 _epc = os::Bsd::ucontext_get_pc((ucontext_t *) context.ucontext());
3738 } else {
3739 // NULL context is unexpected, double-check this is the VMThread
3740 guarantee(thread->is_VM_thread(), "can only be called for VMThread");
3741 }
3742 }
3743
3744 // Suspends the target using the signal mechanism and then grabs the PC before
3745 // resuming the target. Used by the flat-profiler only
3746 ExtendedPC os::get_thread_pc(Thread* thread) {
3747 // Make sure that it is called by the watcher for the VMThread
3748 assert(Thread::current()->is_Watcher_thread(), "Must be watcher");
3749 assert(thread->is_VM_thread(), "Can only be called for VMThread");
3750
3751 PcFetcher fetcher(thread);
3752 fetcher.run();
3753 return fetcher.result();
3754 }
3755
3756 int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime)
3757 {
3758 return pthread_cond_timedwait(_cond, _mutex, _abstime);
3759 }
3760
3761 ////////////////////////////////////////////////////////////////////////////////
3762 // debug support
3763
3764 bool os::find(address addr, outputStream* st) {
3765 Dl_info dlinfo;
3766 memset(&dlinfo, 0, sizeof(dlinfo));
3767 if (dladdr(addr, &dlinfo) != 0) {
3768 st->print(PTR_FORMAT ": ", addr);
3769 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) {
3770 st->print("%s+%#x", dlinfo.dli_sname,
3771 addr - (intptr_t)dlinfo.dli_saddr);
3772 } else if (dlinfo.dli_fbase != NULL) {
3773 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase);
3774 } else {
3775 st->print("<absolute address>");
3776 }
3777 if (dlinfo.dli_fname != NULL) {
3778 st->print(" in %s", dlinfo.dli_fname);
3779 }
3780 if (dlinfo.dli_fbase != NULL) {
3781 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase);
3782 }
3783 st->cr();
3784
3785 if (Verbose) {
3786 // decode some bytes around the PC
3787 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
3788 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size());
3789 address lowest = (address) dlinfo.dli_sname;
3790 if (!lowest) lowest = (address) dlinfo.dli_fbase;
3791 if (begin < lowest) begin = lowest;
3792 Dl_info dlinfo2;
3793 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr
3794 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin)
3795 end = (address) dlinfo2.dli_saddr;
3796 Disassembler::decode(begin, end, st);
3797 }
3798 return true;
3799 }
3800 return false;
3801 }
3802
3803 ////////////////////////////////////////////////////////////////////////////////
3804 // misc
3805
3806 // This does not do anything on Bsd. This is basically a hook for being
3807 // able to use structured exception handling (thread-local exception filters)
3808 // on, e.g., Win32.
3809 void
3810 os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method,
3811 JavaCallArguments* args, Thread* thread) {
3812 f(value, method, args, thread);
3813 }
3814
3815 void os::print_statistics() {
3816 }
3817
3818 int os::message_box(const char* title, const char* message) {
3819 int i;
3820 fdStream err(defaultStream::error_fd());
3821 for (i = 0; i < 78; i++) err.print_raw("=");
3822 err.cr();
3823 err.print_raw_cr(title);
3824 for (i = 0; i < 78; i++) err.print_raw("-");
3825 err.cr();
3826 err.print_raw_cr(message);
3827 for (i = 0; i < 78; i++) err.print_raw("=");
3828 err.cr();
3829
3830 char buf[16];
3831 // Prevent process from exiting upon "read error" without consuming all CPU
3832 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3833
3834 return buf[0] == 'y' || buf[0] == 'Y';
3835 }
3836
3837 int os::stat(const char *path, struct stat *sbuf) {
3838 char pathbuf[MAX_PATH];
3839 if (strlen(path) > MAX_PATH - 1) {
3840 errno = ENAMETOOLONG;
3841 return -1;
3842 }
3843 os::native_path(strcpy(pathbuf, path));
3844 return ::stat(pathbuf, sbuf);
3845 }
3846
3847 bool os::check_heap(bool force) {
3848 return true;
3849 }
3850
3851 int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) {
3852 return ::vsnprintf(buf, count, format, args);
3853 }
3854
3855 // Is a (classpath) directory empty?
3856 bool os::dir_is_empty(const char* path) {
3857 DIR *dir = NULL;
3858 struct dirent *ptr;
3859
3860 dir = opendir(path);
3861 if (dir == NULL) return true;
3862
3863 /* Scan the directory */
3864 bool result = true;
3865 char buf[sizeof(struct dirent) + MAX_PATH];
3866 while (result && (ptr = ::readdir(dir)) != NULL) {
3867 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3868 result = false;
3869 }
3870 }
3871 closedir(dir);
3872 return result;
3873 }
3874
3875 // This code originates from JDK's sysOpen and open64_w
3876 // from src/solaris/hpi/src/system_md.c
3877
3878 #ifndef O_DELETE
3879 #define O_DELETE 0x10000
3880 #endif
3881
3882 // Open a file. Unlink the file immediately after open returns
3883 // if the specified oflag has the O_DELETE flag set.
3884 // O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c
3885
3886 int os::open(const char *path, int oflag, int mode) {
3887
3888 if (strlen(path) > MAX_PATH - 1) {
3889 errno = ENAMETOOLONG;
3890 return -1;
3891 }
3892 int fd;
3893 int o_delete = (oflag & O_DELETE);
3894 oflag = oflag & ~O_DELETE;
3895
3896 fd = ::open(path, oflag, mode);
3897 if (fd == -1) return -1;
3898
3899 //If the open succeeded, the file might still be a directory
3900 {
3901 struct stat buf;
3902 int ret = ::fstat(fd, &buf);
3903 int st_mode = buf.st_mode;
3904
3905 if (ret != -1) {
3906 if ((st_mode & S_IFMT) == S_IFDIR) {
3907 errno = EISDIR;
3908 ::close(fd);
3909 return -1;
3910 }
3911 } else {
3912 ::close(fd);
3913 return -1;
3914 }
3915 }
3916
3917 /*
3918 * All file descriptors that are opened in the JVM and not
3919 * specifically destined for a subprocess should have the
3920 * close-on-exec flag set. If we don't set it, then careless 3rd
3921 * party native code might fork and exec without closing all
3922 * appropriate file descriptors (e.g. as we do in closeDescriptors in
3923 * UNIXProcess.c), and this in turn might:
3924 *
3925 * - cause end-of-file to fail to be detected on some file
3926 * descriptors, resulting in mysterious hangs, or
3927 *
3928 * - might cause an fopen in the subprocess to fail on a system
3929 * suffering from bug 1085341.
3930 *
3931 * (Yes, the default setting of the close-on-exec flag is a Unix
3932 * design flaw)
3933 *
3934 * See:
3935 * 1085341: 32-bit stdio routines should support file descriptors >255
3936 * 4843136: (process) pipe file descriptor from Runtime.exec not being closed
3937 * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
3938 */
3939 #ifdef FD_CLOEXEC
3940 {
3941 int flags = ::fcntl(fd, F_GETFD);
3942 if (flags != -1)
3943 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
3944 }
3945 #endif
3946
3947 if (o_delete != 0) {
3948 ::unlink(path);
3949 }
3950 return fd;
3951 }
3952
3953
3954 // create binary file, rewriting existing file if required
3955 int os::create_binary_file(const char* path, bool rewrite_existing) {
3956 int oflags = O_WRONLY | O_CREAT;
3957 if (!rewrite_existing) {
3958 oflags |= O_EXCL;
3959 }
3960 return ::open(path, oflags, S_IREAD | S_IWRITE);
3961 }
3962
3963 // return current position of file pointer
3964 jlong os::current_file_offset(int fd) {
3965 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
3966 }
3967
3968 // move file pointer to the specified offset
3969 jlong os::seek_to_file_offset(int fd, jlong offset) {
3970 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
3971 }
3972
3973 // This code originates from JDK's sysAvailable
3974 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
3975
3976 int os::available(int fd, jlong *bytes) {
3977 jlong cur, end;
3978 int mode;
3979 struct stat buf;
3980
3981 if (::fstat(fd, &buf) >= 0) {
3982 mode = buf.st_mode;
3983 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
3984 /*
3985 * XXX: is the following call interruptible? If so, this might
3986 * need to go through the INTERRUPT_IO() wrapper as for other
3987 * blocking, interruptible calls in this file.
3988 */
3989 int n;
3990 if (::ioctl(fd, FIONREAD, &n) >= 0) {
3991 *bytes = n;
3992 return 1;
3993 }
3994 }
3995 }
3996 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
3997 return 0;
3998 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
3999 return 0;
4000 } else if (::lseek(fd, cur, SEEK_SET) == -1) {
4001 return 0;
4002 }
4003 *bytes = end - cur;
4004 return 1;
4005 }
4006
4007 int os::socket_available(int fd, jint *pbytes) {
4008 if (fd < 0)
4009 return OS_OK;
4010
4011 int ret;
4012
4013 RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret);
4014
4015 //%% note ioctl can return 0 when successful, JVM_SocketAvailable
4016 // is expected to return 0 on failure and 1 on success to the jdk.
4017
4018 return (ret == OS_ERR) ? 0 : 1;
4019 }
4020
4021 // Map a block of memory.
4022 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
4023 char *addr, size_t bytes, bool read_only,
4024 bool allow_exec) {
4025 int prot;
4026 int flags;
4027
4028 if (read_only) {
4029 prot = PROT_READ;
4030 flags = MAP_SHARED;
4031 } else {
4032 prot = PROT_READ | PROT_WRITE;
4033 flags = MAP_PRIVATE;
4034 }
4035
4036 if (allow_exec) {
4037 prot |= PROT_EXEC;
4038 }
4039
4040 if (addr != NULL) {
4041 flags |= MAP_FIXED;
4042 }
4043
4044 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
4045 fd, file_offset);
4046 if (mapped_address == MAP_FAILED) {
4047 return NULL;
4048 }
4049 return mapped_address;
4050 }
4051
4052
4053 // Remap a block of memory.
4054 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
4055 char *addr, size_t bytes, bool read_only,
4056 bool allow_exec) {
4057 // same as map_memory() on this OS
4058 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
4059 allow_exec);
4060 }
4061
4062
4063 // Unmap a block of memory.
4064 bool os::pd_unmap_memory(char* addr, size_t bytes) {
4065 return munmap(addr, bytes) == 0;
4066 }
4067
4068 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
4069 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
4070 // of a thread.
4071 //
4072 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
4073 // the fast estimate available on the platform.
4074
4075 jlong os::current_thread_cpu_time() {
4076 #ifdef __APPLE__
4077 return os::thread_cpu_time(Thread::current(), true /* user + sys */);
4078 #else
4079 Unimplemented();
4080 return 0;
4081 #endif
4082 }
4083
4084 jlong os::thread_cpu_time(Thread* thread) {
4085 #ifdef __APPLE__
4086 return os::thread_cpu_time(thread, true /* user + sys */);
4087 #else
4088 Unimplemented();
4089 return 0;
4090 #endif
4091 }
4092
4093 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
4094 #ifdef __APPLE__
4095 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
4096 #else
4097 Unimplemented();
4098 return 0;
4099 #endif
4100 }
4101
4102 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
4103 #ifdef __APPLE__
4104 struct thread_basic_info tinfo;
4105 mach_msg_type_number_t tcount = THREAD_INFO_MAX;
4106 kern_return_t kr;
4107 thread_t mach_thread;
4108
4109 mach_thread = thread->osthread()->thread_id();
4110 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
4111 if (kr != KERN_SUCCESS)
4112 return -1;
4113
4114 if (user_sys_cpu_time) {
4115 jlong nanos;
4116 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
4117 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
4118 return nanos;
4119 } else {
4120 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
4121 }
4122 #else
4123 Unimplemented();
4124 return 0;
4125 #endif
4126 }
4127
4128
4129 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4130 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4131 info_ptr->may_skip_backward = false; // elapsed time not wall time
4132 info_ptr->may_skip_forward = false; // elapsed time not wall time
4133 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4134 }
4135
4136 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4137 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4138 info_ptr->may_skip_backward = false; // elapsed time not wall time
4139 info_ptr->may_skip_forward = false; // elapsed time not wall time
4140 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4141 }
4142
4143 bool os::is_thread_cpu_time_supported() {
4144 #ifdef __APPLE__
4145 return true;
4146 #else
4147 return false;
4148 #endif
4149 }
4150
4151 // System loadavg support. Returns -1 if load average cannot be obtained.
4152 // Bsd doesn't yet have a (official) notion of processor sets,
4153 // so just return the system wide load average.
4154 int os::loadavg(double loadavg[], int nelem) {
4155 return ::getloadavg(loadavg, nelem);
4156 }
4157
4158 void os::pause() {
4159 char filename[MAX_PATH];
4160 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
4161 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
4162 } else {
4163 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
4164 }
4165
4166 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
4167 if (fd != -1) {
4168 struct stat buf;
4169 ::close(fd);
4170 while (::stat(filename, &buf) == 0) {
4171 (void)::poll(NULL, 0, 100);
4172 }
4173 } else {
4174 jio_fprintf(stderr,
4175 "Could not open pause file '%s', continuing immediately.\n", filename);
4176 }
4177 }
4178
4179
4180 // Refer to the comments in os_solaris.cpp park-unpark.
4181 //
4182 // Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can
4183 // hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable.
4184 // For specifics regarding the bug see GLIBC BUGID 261237 :
4185 // http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html.
4186 // Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future
4187 // will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar
4188 // is used. (The simple C test-case provided in the GLIBC bug report manifests the
4189 // hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos()
4190 // and monitorenter when we're using 1-0 locking. All those operations may result in
4191 // calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version
4192 // of libpthread avoids the problem, but isn't practical.
4193 //
4194 // Possible remedies:
4195 //
4196 // 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work.
4197 // This is palliative and probabilistic, however. If the thread is preempted
4198 // between the call to compute_abstime() and pthread_cond_timedwait(), more
4199 // than the minimum period may have passed, and the abstime may be stale (in the
4200 // past) resultin in a hang. Using this technique reduces the odds of a hang
4201 // but the JVM is still vulnerable, particularly on heavily loaded systems.
4202 //
4203 // 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead
4204 // of the usual flag-condvar-mutex idiom. The write side of the pipe is set
4205 // NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo)
4206 // reduces to poll()+read(). This works well, but consumes 2 FDs per extant
4207 // thread.
4208 //
4209 // 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread
4210 // that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing
4211 // a timeout request to the chron thread and then blocking via pthread_cond_wait().
4212 // This also works well. In fact it avoids kernel-level scalability impediments
4213 // on certain platforms that don't handle lots of active pthread_cond_timedwait()
4214 // timers in a graceful fashion.
4215 //
4216 // 4. When the abstime value is in the past it appears that control returns
4217 // correctly from pthread_cond_timedwait(), but the condvar is left corrupt.
4218 // Subsequent timedwait/wait calls may hang indefinitely. Given that, we
4219 // can avoid the problem by reinitializing the condvar -- by cond_destroy()
4220 // followed by cond_init() -- after all calls to pthread_cond_timedwait().
4221 // It may be possible to avoid reinitialization by checking the return
4222 // value from pthread_cond_timedwait(). In addition to reinitializing the
4223 // condvar we must establish the invariant that cond_signal() is only called
4224 // within critical sections protected by the adjunct mutex. This prevents
4225 // cond_signal() from "seeing" a condvar that's in the midst of being
4226 // reinitialized or that is corrupt. Sadly, this invariant obviates the
4227 // desirable signal-after-unlock optimization that avoids futile context switching.
4228 //
4229 // I'm also concerned that some versions of NTPL might allocate an auxilliary
4230 // structure when a condvar is used or initialized. cond_destroy() would
4231 // release the helper structure. Our reinitialize-after-timedwait fix
4232 // put excessive stress on malloc/free and locks protecting the c-heap.
4233 //
4234 // We currently use (4). See the WorkAroundNTPLTimedWaitHang flag.
4235 // It may be possible to refine (4) by checking the kernel and NTPL verisons
4236 // and only enabling the work-around for vulnerable environments.
4237
4238 // utility to compute the abstime argument to timedwait:
4239 // millis is the relative timeout time
4240 // abstime will be the absolute timeout time
4241 // TODO: replace compute_abstime() with unpackTime()
4242
4243 static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) {
4244 if (millis < 0) millis = 0;
4245 struct timeval now;
4246 int status = gettimeofday(&now, NULL);
4247 assert(status == 0, "gettimeofday");
4248 jlong seconds = millis / 1000;
4249 millis %= 1000;
4250 if (seconds > 50000000) { // see man cond_timedwait(3T)
4251 seconds = 50000000;
4252 }
4253 abstime->tv_sec = now.tv_sec + seconds;
4254 long usec = now.tv_usec + millis * 1000;
4255 if (usec >= 1000000) {
4256 abstime->tv_sec += 1;
4257 usec -= 1000000;
4258 }
4259 abstime->tv_nsec = usec * 1000;
4260 return abstime;
4261 }
4262
4263
4264 // Test-and-clear _Event, always leaves _Event set to 0, returns immediately.
4265 // Conceptually TryPark() should be equivalent to park(0).
4266
4267 int os::PlatformEvent::TryPark() {
4268 for (;;) {
4269 const int v = _Event ;
4270 guarantee ((v == 0) || (v == 1), "invariant") ;
4271 if (Atomic::cmpxchg (0, &_Event, v) == v) return v ;
4272 }
4273 }
4274
4275 void os::PlatformEvent::park() { // AKA "down()"
4276 // Invariant: Only the thread associated with the Event/PlatformEvent
4277 // may call park().
4278 // TODO: assert that _Assoc != NULL or _Assoc == Self
4279 int v ;
4280 for (;;) {
4281 v = _Event ;
4282 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4283 }
4284 guarantee (v >= 0, "invariant") ;
4285 if (v == 0) {
4286 // Do this the hard way by blocking ...
4287 int status = pthread_mutex_lock(_mutex);
4288 assert_status(status == 0, status, "mutex_lock");
4289 guarantee (_nParked == 0, "invariant") ;
4290 ++ _nParked ;
4291 while (_Event < 0) {
4292 status = pthread_cond_wait(_cond, _mutex);
4293 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ...
4294 // Treat this the same as if the wait was interrupted
4295 if (status == ETIMEDOUT) { status = EINTR; }
4296 assert_status(status == 0 || status == EINTR, status, "cond_wait");
4297 }
4298 -- _nParked ;
4299
4300 _Event = 0 ;
4301 status = pthread_mutex_unlock(_mutex);
4302 assert_status(status == 0, status, "mutex_unlock");
4303 // Paranoia to ensure our locked and lock-free paths interact
4304 // correctly with each other.
4305 OrderAccess::fence();
4306 }
4307 guarantee (_Event >= 0, "invariant") ;
4308 }
4309
4310 int os::PlatformEvent::park(jlong millis) {
4311 guarantee (_nParked == 0, "invariant") ;
4312
4313 int v ;
4314 for (;;) {
4315 v = _Event ;
4316 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4317 }
4318 guarantee (v >= 0, "invariant") ;
4319 if (v != 0) return OS_OK ;
4320
4321 // We do this the hard way, by blocking the thread.
4322 // Consider enforcing a minimum timeout value.
4323 struct timespec abst;
4324 compute_abstime(&abst, millis);
4325
4326 int ret = OS_TIMEOUT;
4327 int status = pthread_mutex_lock(_mutex);
4328 assert_status(status == 0, status, "mutex_lock");
4329 guarantee (_nParked == 0, "invariant") ;
4330 ++_nParked ;
4331
4332 // Object.wait(timo) will return because of
4333 // (a) notification
4334 // (b) timeout
4335 // (c) thread.interrupt
4336 //
4337 // Thread.interrupt and object.notify{All} both call Event::set.
4338 // That is, we treat thread.interrupt as a special case of notification.
4339 // The underlying Solaris implementation, cond_timedwait, admits
4340 // spurious/premature wakeups, but the JLS/JVM spec prevents the
4341 // JVM from making those visible to Java code. As such, we must
4342 // filter out spurious wakeups. We assume all ETIME returns are valid.
4343 //
4344 // TODO: properly differentiate simultaneous notify+interrupt.
4345 // In that case, we should propagate the notify to another waiter.
4346
4347 while (_Event < 0) {
4348 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst);
4349 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4350 pthread_cond_destroy (_cond);
4351 pthread_cond_init (_cond, NULL) ;
4352 }
4353 assert_status(status == 0 || status == EINTR ||
4354 status == ETIMEDOUT,
4355 status, "cond_timedwait");
4356 if (!FilterSpuriousWakeups) break ; // previous semantics
4357 if (status == ETIMEDOUT) break ;
4358 // We consume and ignore EINTR and spurious wakeups.
4359 }
4360 --_nParked ;
4361 if (_Event >= 0) {
4362 ret = OS_OK;
4363 }
4364 _Event = 0 ;
4365 status = pthread_mutex_unlock(_mutex);
4366 assert_status(status == 0, status, "mutex_unlock");
4367 assert (_nParked == 0, "invariant") ;
4368 // Paranoia to ensure our locked and lock-free paths interact
4369 // correctly with each other.
4370 OrderAccess::fence();
4371 return ret;
4372 }
4373
4374 void os::PlatformEvent::unpark() {
4375 // Transitions for _Event:
4376 // 0 :=> 1
4377 // 1 :=> 1
4378 // -1 :=> either 0 or 1; must signal target thread
4379 // That is, we can safely transition _Event from -1 to either
4380 // 0 or 1. Forcing 1 is slightly more efficient for back-to-back
4381 // unpark() calls.
4382 // See also: "Semaphores in Plan 9" by Mullender & Cox
4383 //
4384 // Note: Forcing a transition from "-1" to "1" on an unpark() means
4385 // that it will take two back-to-back park() calls for the owning
4386 // thread to block. This has the benefit of forcing a spurious return
4387 // from the first park() call after an unpark() call which will help
4388 // shake out uses of park() and unpark() without condition variables.
4389
4390 if (Atomic::xchg(1, &_Event) >= 0) return;
4391
4392 // Wait for the thread associated with the event to vacate
4393 int status = pthread_mutex_lock(_mutex);
4394 assert_status(status == 0, status, "mutex_lock");
4395 int AnyWaiters = _nParked;
4396 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant");
4397 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) {
4398 AnyWaiters = 0;
4399 pthread_cond_signal(_cond);
4400 }
4401 status = pthread_mutex_unlock(_mutex);
4402 assert_status(status == 0, status, "mutex_unlock");
4403 if (AnyWaiters != 0) {
4404 status = pthread_cond_signal(_cond);
4405 assert_status(status == 0, status, "cond_signal");
4406 }
4407
4408 // Note that we signal() _after dropping the lock for "immortal" Events.
4409 // This is safe and avoids a common class of futile wakeups. In rare
4410 // circumstances this can cause a thread to return prematurely from
4411 // cond_{timed}wait() but the spurious wakeup is benign and the victim will
4412 // simply re-test the condition and re-park itself.
4413 }
4414
4415
4416 // JSR166
4417 // -------------------------------------------------------
4418
4419 /*
4420 * The solaris and bsd implementations of park/unpark are fairly
4421 * conservative for now, but can be improved. They currently use a
4422 * mutex/condvar pair, plus a a count.
4423 * Park decrements count if > 0, else does a condvar wait. Unpark
4424 * sets count to 1 and signals condvar. Only one thread ever waits
4425 * on the condvar. Contention seen when trying to park implies that someone
4426 * is unparking you, so don't wait. And spurious returns are fine, so there
4427 * is no need to track notifications.
4428 */
4429
4430 #define MAX_SECS 100000000
4431 /*
4432 * This code is common to bsd and solaris and will be moved to a
4433 * common place in dolphin.
4434 *
4435 * The passed in time value is either a relative time in nanoseconds
4436 * or an absolute time in milliseconds. Either way it has to be unpacked
4437 * into suitable seconds and nanoseconds components and stored in the
4438 * given timespec structure.
4439 * Given time is a 64-bit value and the time_t used in the timespec is only
4440 * a signed-32-bit value (except on 64-bit Bsd) we have to watch for
4441 * overflow if times way in the future are given. Further on Solaris versions
4442 * prior to 10 there is a restriction (see cond_timedwait) that the specified
4443 * number of seconds, in abstime, is less than current_time + 100,000,000.
4444 * As it will be 28 years before "now + 100000000" will overflow we can
4445 * ignore overflow and just impose a hard-limit on seconds using the value
4446 * of "now + 100,000,000". This places a limit on the timeout of about 3.17
4447 * years from "now".
4448 */
4449
4450 static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) {
4451 assert (time > 0, "convertTime");
4452
4453 struct timeval now;
4454 int status = gettimeofday(&now, NULL);
4455 assert(status == 0, "gettimeofday");
4456
4457 time_t max_secs = now.tv_sec + MAX_SECS;
4458
4459 if (isAbsolute) {
4460 jlong secs = time / 1000;
4461 if (secs > max_secs) {
4462 absTime->tv_sec = max_secs;
4463 }
4464 else {
4465 absTime->tv_sec = secs;
4466 }
4467 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC;
4468 }
4469 else {
4470 jlong secs = time / NANOSECS_PER_SEC;
4471 if (secs >= MAX_SECS) {
4472 absTime->tv_sec = max_secs;
4473 absTime->tv_nsec = 0;
4474 }
4475 else {
4476 absTime->tv_sec = now.tv_sec + secs;
4477 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000;
4478 if (absTime->tv_nsec >= NANOSECS_PER_SEC) {
4479 absTime->tv_nsec -= NANOSECS_PER_SEC;
4480 ++absTime->tv_sec; // note: this must be <= max_secs
4481 }
4482 }
4483 }
4484 assert(absTime->tv_sec >= 0, "tv_sec < 0");
4485 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs");
4486 assert(absTime->tv_nsec >= 0, "tv_nsec < 0");
4487 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec");
4488 }
4489
4490 void Parker::park(bool isAbsolute, jlong time) {
4491 // Ideally we'd do something useful while spinning, such
4492 // as calling unpackTime().
4493
4494 // Optional fast-path check:
4495 // Return immediately if a permit is available.
4496 // We depend on Atomic::xchg() having full barrier semantics
4497 // since we are doing a lock-free update to _counter.
4498 if (Atomic::xchg(0, &_counter) > 0) return;
4499
4500 Thread* thread = Thread::current();
4501 assert(thread->is_Java_thread(), "Must be JavaThread");
4502 JavaThread *jt = (JavaThread *)thread;
4503
4504 // Optional optimization -- avoid state transitions if there's an interrupt pending.
4505 // Check interrupt before trying to wait
4506 if (Thread::is_interrupted(thread, false)) {
4507 return;
4508 }
4509
4510 // Next, demultiplex/decode time arguments
4511 struct timespec absTime;
4512 if (time < 0 || (isAbsolute && time == 0) ) { // don't wait at all
4513 return;
4514 }
4515 if (time > 0) {
4516 unpackTime(&absTime, isAbsolute, time);
4517 }
4518
4519
4520 // Enter safepoint region
4521 // Beware of deadlocks such as 6317397.
4522 // The per-thread Parker:: mutex is a classic leaf-lock.
4523 // In particular a thread must never block on the Threads_lock while
4524 // holding the Parker:: mutex. If safepoints are pending both the
4525 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock.
4526 ThreadBlockInVM tbivm(jt);
4527
4528 // Don't wait if cannot get lock since interference arises from
4529 // unblocking. Also. check interrupt before trying wait
4530 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) {
4531 return;
4532 }
4533
4534 int status ;
4535 if (_counter > 0) { // no wait needed
4536 _counter = 0;
4537 status = pthread_mutex_unlock(_mutex);
4538 assert (status == 0, "invariant") ;
4539 // Paranoia to ensure our locked and lock-free paths interact
4540 // correctly with each other and Java-level accesses.
4541 OrderAccess::fence();
4542 return;
4543 }
4544
4545 #ifdef ASSERT
4546 // Don't catch signals while blocked; let the running threads have the signals.
4547 // (This allows a debugger to break into the running thread.)
4548 sigset_t oldsigs;
4549 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals();
4550 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs);
4551 #endif
4552
4553 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
4554 jt->set_suspend_equivalent();
4555 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
4556
4557 if (time == 0) {
4558 status = pthread_cond_wait (_cond, _mutex) ;
4559 } else {
4560 status = os::Bsd::safe_cond_timedwait (_cond, _mutex, &absTime) ;
4561 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4562 pthread_cond_destroy (_cond) ;
4563 pthread_cond_init (_cond, NULL);
4564 }
4565 }
4566 assert_status(status == 0 || status == EINTR ||
4567 status == ETIMEDOUT,
4568 status, "cond_timedwait");
4569
4570 #ifdef ASSERT
4571 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL);
4572 #endif
4573
4574 _counter = 0 ;
4575 status = pthread_mutex_unlock(_mutex) ;
4576 assert_status(status == 0, status, "invariant") ;
4577 // Paranoia to ensure our locked and lock-free paths interact
4578 // correctly with each other and Java-level accesses.
4579 OrderAccess::fence();
4580
4581 // If externally suspended while waiting, re-suspend
4582 if (jt->handle_special_suspend_equivalent_condition()) {
4583 jt->java_suspend_self();
4584 }
4585 }
4586
4587 void Parker::unpark() {
4588 int s, status ;
4589 status = pthread_mutex_lock(_mutex);
4590 assert (status == 0, "invariant") ;
4591 s = _counter;
4592 _counter = 1;
4593 if (s < 1) {
4594 if (WorkAroundNPTLTimedWaitHang) {
4595 status = pthread_cond_signal (_cond) ;
4596 assert (status == 0, "invariant") ;
4597 status = pthread_mutex_unlock(_mutex);
4598 assert (status == 0, "invariant") ;
4599 } else {
4600 status = pthread_mutex_unlock(_mutex);
4601 assert (status == 0, "invariant") ;
4602 status = pthread_cond_signal (_cond) ;
4603 assert (status == 0, "invariant") ;
4604 }
4605 } else {
4606 pthread_mutex_unlock(_mutex);
4607 assert (status == 0, "invariant") ;
4608 }
4609 }
4610
4611
4612 /* Darwin has no "environ" in a dynamic library. */
4613 #ifdef __APPLE__
4614 #include <crt_externs.h>
4615 #define environ (*_NSGetEnviron())
4616 #else
4617 extern char** environ;
4618 #endif
4619
4620 // Run the specified command in a separate process. Return its exit value,
4621 // or -1 on failure (e.g. can't fork a new process).
4622 // Unlike system(), this function can be called from signal handler. It
4623 // doesn't block SIGINT et al.
4624 int os::fork_and_exec(char* cmd) {
4625 const char * argv[4] = {"sh", "-c", cmd, NULL};
4626
4627 // fork() in BsdThreads/NPTL is not async-safe. It needs to run
4628 // pthread_atfork handlers and reset pthread library. All we need is a
4629 // separate process to execve. Make a direct syscall to fork process.
4630 // On IA64 there's no fork syscall, we have to use fork() and hope for
4631 // the best...
4632 pid_t pid = fork();
4633
4634 if (pid < 0) {
4635 // fork failed
4636 return -1;
4637
4638 } else if (pid == 0) {
4639 // child process
4640
4641 // execve() in BsdThreads will call pthread_kill_other_threads_np()
4642 // first to kill every thread on the thread list. Because this list is
4643 // not reset by fork() (see notes above), execve() will instead kill
4644 // every thread in the parent process. We know this is the only thread
4645 // in the new process, so make a system call directly.
4646 // IA64 should use normal execve() from glibc to match the glibc fork()
4647 // above.
4648 execve("/bin/sh", (char* const*)argv, environ);
4649
4650 // execve failed
4651 _exit(-1);
4652
4653 } else {
4654 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
4655 // care about the actual exit code, for now.
4656
4657 int status;
4658
4659 // Wait for the child process to exit. This returns immediately if
4660 // the child has already exited. */
4661 while (waitpid(pid, &status, 0) < 0) {
4662 switch (errno) {
4663 case ECHILD: return 0;
4664 case EINTR: break;
4665 default: return -1;
4666 }
4667 }
4668
4669 if (WIFEXITED(status)) {
4670 // The child exited normally; get its exit code.
4671 return WEXITSTATUS(status);
4672 } else if (WIFSIGNALED(status)) {
4673 // The child exited because of a signal
4674 // The best value to return is 0x80 + signal number,
4675 // because that is what all Unix shells do, and because
4676 // it allows callers to distinguish between process exit and
4677 // process death by signal.
4678 return 0x80 + WTERMSIG(status);
4679 } else {
4680 // Unknown exit code; pass it through
4681 return status;
4682 }
4683 }
4684 }
4685
4686 // is_headless_jre()
4687 //
4688 // Test for the existence of xawt/libmawt.so or libawt_xawt.so
4689 // in order to report if we are running in a headless jre
4690 //
4691 // Since JDK8 xawt/libmawt.so was moved into the same directory
4692 // as libawt.so, and renamed libawt_xawt.so
4693 //
4694 bool os::is_headless_jre() {
4695 struct stat statbuf;
4696 char buf[MAXPATHLEN];
4697 char libmawtpath[MAXPATHLEN];
4698 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX;
4699 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX;
4700 char *p;
4701
4702 // Get path to libjvm.so
4703 os::jvm_path(buf, sizeof(buf));
4704
4705 // Get rid of libjvm.so
4706 p = strrchr(buf, '/');
4707 if (p == NULL) return false;
4708 else *p = '\0';
4709
4710 // Get rid of client or server
4711 p = strrchr(buf, '/');
4712 if (p == NULL) return false;
4713 else *p = '\0';
4714
4715 // check xawt/libmawt.so
4716 strcpy(libmawtpath, buf);
4717 strcat(libmawtpath, xawtstr);
4718 if (::stat(libmawtpath, &statbuf) == 0) return false;
4719
4720 // check libawt_xawt.so
4721 strcpy(libmawtpath, buf);
4722 strcat(libmawtpath, new_xawtstr);
4723 if (::stat(libmawtpath, &statbuf) == 0) return false;
4724
4725 return true;
4726 }
4727
4728 // Get the default path to the core file
4729 // Returns the length of the string
4730 int os::get_core_path(char* buffer, size_t bufferSize) {
4731 int n = jio_snprintf(buffer, bufferSize, "/cores");
4732
4733 // Truncate if theoretical string was longer than bufferSize
4734 n = MIN2(n, (int)bufferSize);
4735
4736 return n;
4737 }
4738