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(PPC)
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(mach_port_t mach_thread_port) {
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_port, THREAD_IDENTIFIER_INFO,
651 (thread_info_t) &m_ident_info, &count);
652
653 return m_ident_info.thread_id;
654 }
655 #endif
656
657 // Thread start routine for all newly created threads
658 static void *java_start(Thread *thread) {
659 // Try to randomize the cache line index of hot stack frames.
660 // This helps when threads of the same stack traces evict each other's
661 // cache lines. The threads can be either from the same JVM instance, or
662 // from different JVM instances. The benefit is especially true for
663 // processors with hyperthreading technology.
664 static int counter = 0;
665 int pid = os::current_process_id();
666 alloca(((pid ^ counter++) & 7) * 128);
667
668 ThreadLocalStorage::set_thread(thread);
669
670 OSThread* osthread = thread->osthread();
671 Monitor* sync = osthread->startThread_lock();
672
673 // non floating stack BsdThreads needs extra check, see above
674 if (!_thread_safety_check(thread)) {
675 // notify parent thread
676 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
677 osthread->set_state(ZOMBIE);
678 sync->notify_all();
679 return NULL;
680 }
681
682 #ifdef __APPLE__
683 // thread_id is mach thread on macos, which pthreads graciously caches and provides for us
684 mach_port_t thread_id = ::pthread_mach_thread_np(::pthread_self());
685 guarantee(thread_id != 0, "thread id missing from pthreads");
686 osthread->set_thread_id(thread_id);
687
688 uint64_t unique_thread_id = locate_unique_thread_id(thread_id);
689 guarantee(unique_thread_id != 0, "unique thread id was not found");
690 osthread->set_unique_thread_id(unique_thread_id);
691 #else
692 // thread_id is pthread_id on BSD
693 osthread->set_thread_id(::pthread_self());
694 #endif
695 // initialize signal mask for this thread
696 os::Bsd::hotspot_sigmask(thread);
697
698 // initialize floating point control register
699 os::Bsd::init_thread_fpu_state();
700
701 #ifdef __APPLE__
702 // register thread with objc gc
703 if (objc_registerThreadWithCollectorFunction != NULL) {
704 objc_registerThreadWithCollectorFunction();
705 }
706 #endif
707
708 // handshaking with parent thread
709 {
710 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
711
712 // notify parent thread
713 osthread->set_state(INITIALIZED);
714 sync->notify_all();
715
716 // wait until os::start_thread()
717 while (osthread->get_state() == INITIALIZED) {
718 sync->wait(Mutex::_no_safepoint_check_flag);
719 }
720 }
721
722 // call one more level start routine
723 thread->run();
724
725 return 0;
726 }
727
728 bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) {
729 assert(thread->osthread() == NULL, "caller responsible");
730
731 // Allocate the OSThread object
732 OSThread* osthread = new OSThread(NULL, NULL);
733 if (osthread == NULL) {
734 return false;
735 }
736
737 // set the correct thread state
738 osthread->set_thread_type(thr_type);
739
740 // Initial state is ALLOCATED but not INITIALIZED
741 osthread->set_state(ALLOCATED);
742
743 thread->set_osthread(osthread);
744
745 // init thread attributes
746 pthread_attr_t attr;
747 pthread_attr_init(&attr);
748 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
749
750 // stack size
751 if (os::Bsd::supports_variable_stack_size()) {
752 // calculate stack size if it's not specified by caller
753 if (stack_size == 0) {
754 stack_size = os::Bsd::default_stack_size(thr_type);
755
756 switch (thr_type) {
757 case os::java_thread:
758 // Java threads use ThreadStackSize which default value can be
759 // changed with the flag -Xss
760 assert (JavaThread::stack_size_at_create() > 0, "this should be set");
761 stack_size = JavaThread::stack_size_at_create();
762 break;
763 case os::compiler_thread:
764 if (CompilerThreadStackSize > 0) {
765 stack_size = (size_t)(CompilerThreadStackSize * K);
766 break;
767 } // else fall through:
768 // use VMThreadStackSize if CompilerThreadStackSize is not defined
769 case os::vm_thread:
770 case os::pgc_thread:
771 case os::cgc_thread:
772 case os::watcher_thread:
773 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K);
774 break;
775 }
776 }
777
778 stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed);
779 pthread_attr_setstacksize(&attr, stack_size);
780 } else {
781 // let pthread_create() pick the default value.
782 }
783
784 ThreadState state;
785
786 {
787 pthread_t tid;
788 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread);
789
790 pthread_attr_destroy(&attr);
791
792 if (ret != 0) {
793 if (PrintMiscellaneous && (Verbose || WizardMode)) {
794 perror("pthread_create()");
795 }
796 // Need to clean up stuff we've allocated so far
797 thread->set_osthread(NULL);
798 delete osthread;
799 return false;
800 }
801
802 // Store pthread info into the OSThread
803 osthread->set_pthread_id(tid);
804
805 // Wait until child thread is either initialized or aborted
806 {
807 Monitor* sync_with_child = osthread->startThread_lock();
808 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
809 while ((state = osthread->get_state()) == ALLOCATED) {
810 sync_with_child->wait(Mutex::_no_safepoint_check_flag);
811 }
812 }
813
814 }
815
816 // Aborted due to thread limit being reached
817 if (state == ZOMBIE) {
818 thread->set_osthread(NULL);
819 delete osthread;
820 return false;
821 }
822
823 // The thread is returned suspended (in state INITIALIZED),
824 // and is started higher up in the call chain
825 assert(state == INITIALIZED, "race condition");
826 return true;
827 }
828
829 /////////////////////////////////////////////////////////////////////////////
830 // attach existing thread
831
832 // bootstrap the main thread
833 bool os::create_main_thread(JavaThread* thread) {
834 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
835 return create_attached_thread(thread);
836 }
837
838 bool os::create_attached_thread(JavaThread* thread) {
839 #ifdef ASSERT
840 thread->verify_not_published();
841 #endif
842
843 // Allocate the OSThread object
844 OSThread* osthread = new OSThread(NULL, NULL);
845
846 if (osthread == NULL) {
847 return false;
848 }
849
850 // Store pthread info into the OSThread
851 #ifdef __APPLE__
852 // thread_id is mach thread on macos, which pthreads graciously caches and provides for us
853 mach_port_t thread_id = ::pthread_mach_thread_np(::pthread_self());
854 guarantee(thread_id != 0, "just checking");
855 osthread->set_thread_id(thread_id);
856
857 uint64_t unique_thread_id = locate_unique_thread_id(thread_id);
858 guarantee(unique_thread_id != 0, "just checking");
859 osthread->set_unique_thread_id(unique_thread_id);
860 #else
861 osthread->set_thread_id(::pthread_self());
862 #endif
863 osthread->set_pthread_id(::pthread_self());
864
865 // initialize floating point control register
866 os::Bsd::init_thread_fpu_state();
867
868 // Initial thread state is RUNNABLE
869 osthread->set_state(RUNNABLE);
870
871 thread->set_osthread(osthread);
872
873 // initialize signal mask for this thread
874 // and save the caller's signal mask
875 os::Bsd::hotspot_sigmask(thread);
876
877 return true;
878 }
879
880 void os::pd_start_thread(Thread* thread) {
881 OSThread * osthread = thread->osthread();
882 assert(osthread->get_state() != INITIALIZED, "just checking");
883 Monitor* sync_with_child = osthread->startThread_lock();
884 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
885 sync_with_child->notify();
886 }
887
888 // Free Bsd resources related to the OSThread
889 void os::free_thread(OSThread* osthread) {
890 assert(osthread != NULL, "osthread not set");
891
892 if (Thread::current()->osthread() == osthread) {
893 // Restore caller's signal mask
894 sigset_t sigmask = osthread->caller_sigmask();
895 pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
896 }
897
898 delete osthread;
899 }
900
901 //////////////////////////////////////////////////////////////////////////////
902 // thread local storage
903
904 int os::allocate_thread_local_storage() {
905 pthread_key_t key;
906 int rslt = pthread_key_create(&key, NULL);
907 assert(rslt == 0, "cannot allocate thread local storage");
908 return (int)key;
909 }
910
911 // Note: This is currently not used by VM, as we don't destroy TLS key
912 // on VM exit.
913 void os::free_thread_local_storage(int index) {
914 int rslt = pthread_key_delete((pthread_key_t)index);
915 assert(rslt == 0, "invalid index");
916 }
917
918 void os::thread_local_storage_at_put(int index, void* value) {
919 int rslt = pthread_setspecific((pthread_key_t)index, value);
920 assert(rslt == 0, "pthread_setspecific failed");
921 }
922
923 extern "C" Thread* get_thread() {
924 return ThreadLocalStorage::thread();
925 }
926
927
928 ////////////////////////////////////////////////////////////////////////////////
929 // time support
930
931 // Time since start-up in seconds to a fine granularity.
932 // Used by VMSelfDestructTimer and the MemProfiler.
933 double os::elapsedTime() {
934
935 return (double)(os::elapsed_counter()) * 0.000001;
936 }
937
938 jlong os::elapsed_counter() {
939 timeval time;
940 int status = gettimeofday(&time, NULL);
941 return jlong(time.tv_sec) * 1000 * 1000 + jlong(time.tv_usec) - initial_time_count;
942 }
943
944 jlong os::elapsed_frequency() {
945 return (1000 * 1000);
946 }
947
948 bool os::supports_vtime() { return true; }
949 bool os::enable_vtime() { return false; }
950 bool os::vtime_enabled() { return false; }
951
952 double os::elapsedVTime() {
953 // better than nothing, but not much
954 return elapsedTime();
955 }
956
957 jlong os::javaTimeMillis() {
958 timeval time;
959 int status = gettimeofday(&time, NULL);
960 assert(status != -1, "bsd error");
961 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
962 }
963
964 #ifndef CLOCK_MONOTONIC
965 #define CLOCK_MONOTONIC (1)
966 #endif
967
968 #ifdef __APPLE__
969 void os::Bsd::clock_init() {
970 // XXXDARWIN: Investigate replacement monotonic clock
971 }
972 #else
973 void os::Bsd::clock_init() {
974 struct timespec res;
975 struct timespec tp;
976 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
977 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) {
978 // yes, monotonic clock is supported
979 _clock_gettime = ::clock_gettime;
980 }
981 }
982 #endif
983
984
985 jlong os::javaTimeNanos() {
986 if (Bsd::supports_monotonic_clock()) {
987 struct timespec tp;
988 int status = Bsd::clock_gettime(CLOCK_MONOTONIC, &tp);
989 assert(status == 0, "gettime error");
990 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
991 return result;
992 } else {
993 timeval time;
994 int status = gettimeofday(&time, NULL);
995 assert(status != -1, "bsd error");
996 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
997 return 1000 * usecs;
998 }
999 }
1000
1001 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
1002 if (Bsd::supports_monotonic_clock()) {
1003 info_ptr->max_value = ALL_64_BITS;
1004
1005 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
1006 info_ptr->may_skip_backward = false; // not subject to resetting or drifting
1007 info_ptr->may_skip_forward = false; // not subject to resetting or drifting
1008 } else {
1009 // gettimeofday - based on time in seconds since the Epoch thus does not wrap
1010 info_ptr->max_value = ALL_64_BITS;
1011
1012 // gettimeofday is a real time clock so it skips
1013 info_ptr->may_skip_backward = true;
1014 info_ptr->may_skip_forward = true;
1015 }
1016
1017 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
1018 }
1019
1020 // Return the real, user, and system times in seconds from an
1021 // arbitrary fixed point in the past.
1022 bool os::getTimesSecs(double* process_real_time,
1023 double* process_user_time,
1024 double* process_system_time) {
1025 struct tms ticks;
1026 clock_t real_ticks = times(&ticks);
1027
1028 if (real_ticks == (clock_t) (-1)) {
1029 return false;
1030 } else {
1031 double ticks_per_second = (double) clock_tics_per_sec;
1032 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1033 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1034 *process_real_time = ((double) real_ticks) / ticks_per_second;
1035
1036 return true;
1037 }
1038 }
1039
1040
1041 char * os::local_time_string(char *buf, size_t buflen) {
1042 struct tm t;
1043 time_t long_time;
1044 time(&long_time);
1045 localtime_r(&long_time, &t);
1046 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1047 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1048 t.tm_hour, t.tm_min, t.tm_sec);
1049 return buf;
1050 }
1051
1052 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
1053 return localtime_r(clock, res);
1054 }
1055
1056 ////////////////////////////////////////////////////////////////////////////////
1057 // runtime exit support
1058
1059 // Note: os::shutdown() might be called very early during initialization, or
1060 // called from signal handler. Before adding something to os::shutdown(), make
1061 // sure it is async-safe and can handle partially initialized VM.
1062 void os::shutdown() {
1063
1064 // allow PerfMemory to attempt cleanup of any persistent resources
1065 perfMemory_exit();
1066
1067 // needs to remove object in file system
1068 AttachListener::abort();
1069
1070 // flush buffered output, finish log files
1071 ostream_abort();
1072
1073 // Check for abort hook
1074 abort_hook_t abort_hook = Arguments::abort_hook();
1075 if (abort_hook != NULL) {
1076 abort_hook();
1077 }
1078
1079 }
1080
1081 // Note: os::abort() might be called very early during initialization, or
1082 // called from signal handler. Before adding something to os::abort(), make
1083 // sure it is async-safe and can handle partially initialized VM.
1084 void os::abort(bool dump_core) {
1085 os::shutdown();
1086 if (dump_core) {
1087 #ifndef PRODUCT
1088 fdStream out(defaultStream::output_fd());
1089 out.print_raw("Current thread is ");
1090 char buf[16];
1091 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
1092 out.print_raw_cr(buf);
1093 out.print_raw_cr("Dumping core ...");
1094 #endif
1095 ::abort(); // dump core
1096 }
1097
1098 ::exit(1);
1099 }
1100
1101 // Die immediately, no exit hook, no abort hook, no cleanup.
1102 void os::die() {
1103 // _exit() on BsdThreads only kills current thread
1104 ::abort();
1105 }
1106
1107 // unused on bsd for now.
1108 void os::set_error_file(const char *logfile) {}
1109
1110
1111 // This method is a copy of JDK's sysGetLastErrorString
1112 // from src/solaris/hpi/src/system_md.c
1113
1114 size_t os::lasterror(char *buf, size_t len) {
1115
1116 if (errno == 0) return 0;
1117
1118 const char *s = ::strerror(errno);
1119 size_t n = ::strlen(s);
1120 if (n >= len) {
1121 n = len - 1;
1122 }
1123 ::strncpy(buf, s, n);
1124 buf[n] = '\0';
1125 return n;
1126 }
1127
1128 intx os::current_thread_id() {
1129 #ifdef __APPLE__
1130 return (intx)::pthread_mach_thread_np(::pthread_self());
1131 #else
1132 return (intx)::pthread_self();
1133 #endif
1134 }
1135 int os::current_process_id() {
1136
1137 // Under the old bsd thread library, bsd gives each thread
1138 // its own process id. Because of this each thread will return
1139 // a different pid if this method were to return the result
1140 // of getpid(2). Bsd provides no api that returns the pid
1141 // of the launcher thread for the vm. This implementation
1142 // returns a unique pid, the pid of the launcher thread
1143 // that starts the vm 'process'.
1144
1145 // Under the NPTL, getpid() returns the same pid as the
1146 // launcher thread rather than a unique pid per thread.
1147 // Use gettid() if you want the old pre NPTL behaviour.
1148
1149 // if you are looking for the result of a call to getpid() that
1150 // returns a unique pid for the calling thread, then look at the
1151 // OSThread::thread_id() method in osThread_bsd.hpp file
1152
1153 return (int)(_initial_pid ? _initial_pid : getpid());
1154 }
1155
1156 // DLL functions
1157
1158 #define JNI_LIB_PREFIX "lib"
1159 #ifdef __APPLE__
1160 #define JNI_LIB_SUFFIX ".dylib"
1161 #else
1162 #define JNI_LIB_SUFFIX ".so"
1163 #endif
1164
1165 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1166
1167 // This must be hard coded because it's the system's temporary
1168 // directory not the java application's temp directory, ala java.io.tmpdir.
1169 #ifdef __APPLE__
1170 // macosx has a secure per-user temporary directory
1171 char temp_path_storage[PATH_MAX];
1172 const char* os::get_temp_directory() {
1173 static char *temp_path = NULL;
1174 if (temp_path == NULL) {
1175 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
1176 if (pathSize == 0 || pathSize > PATH_MAX) {
1177 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
1178 }
1179 temp_path = temp_path_storage;
1180 }
1181 return temp_path;
1182 }
1183 #else /* __APPLE__ */
1184 const char* os::get_temp_directory() { return "/tmp"; }
1185 #endif /* __APPLE__ */
1186
1187 static bool file_exists(const char* filename) {
1188 struct stat statbuf;
1189 if (filename == NULL || strlen(filename) == 0) {
1190 return false;
1191 }
1192 return os::stat(filename, &statbuf) == 0;
1193 }
1194
1195 bool os::dll_build_name(char* buffer, size_t buflen,
1196 const char* pname, const char* fname) {
1197 bool retval = false;
1198 // Copied from libhpi
1199 const size_t pnamelen = pname ? strlen(pname) : 0;
1200
1201 // Return error on buffer overflow.
1202 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) {
1203 return retval;
1204 }
1205
1206 if (pnamelen == 0) {
1207 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname);
1208 retval = true;
1209 } else if (strchr(pname, *os::path_separator()) != NULL) {
1210 int n;
1211 char** pelements = split_path(pname, &n);
1212 if (pelements == NULL) {
1213 return false;
1214 }
1215 for (int i = 0 ; i < n ; i++) {
1216 // Really shouldn't be NULL, but check can't hurt
1217 if (pelements[i] == NULL || strlen(pelements[i]) == 0) {
1218 continue; // skip the empty path values
1219 }
1220 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX,
1221 pelements[i], fname);
1222 if (file_exists(buffer)) {
1223 retval = true;
1224 break;
1225 }
1226 }
1227 // release the storage
1228 for (int i = 0 ; i < n ; i++) {
1229 if (pelements[i] != NULL) {
1230 FREE_C_HEAP_ARRAY(char, pelements[i], mtInternal);
1231 }
1232 }
1233 if (pelements != NULL) {
1234 FREE_C_HEAP_ARRAY(char*, pelements, mtInternal);
1235 }
1236 } else {
1237 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname);
1238 retval = true;
1239 }
1240 return retval;
1241 }
1242
1243 // check if addr is inside libjvm.so
1244 bool os::address_is_in_vm(address addr) {
1245 static address libjvm_base_addr;
1246 Dl_info dlinfo;
1247
1248 if (libjvm_base_addr == NULL) {
1249 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) {
1250 libjvm_base_addr = (address)dlinfo.dli_fbase;
1251 }
1252 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1253 }
1254
1255 if (dladdr((void *)addr, &dlinfo) != 0) {
1256 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1257 }
1258
1259 return false;
1260 }
1261
1262
1263 #define MACH_MAXSYMLEN 256
1264
1265 bool os::dll_address_to_function_name(address addr, char *buf,
1266 int buflen, int *offset) {
1267 // buf is not optional, but offset is optional
1268 assert(buf != NULL, "sanity check");
1269
1270 Dl_info dlinfo;
1271 char localbuf[MACH_MAXSYMLEN];
1272
1273 if (dladdr((void*)addr, &dlinfo) != 0) {
1274 // see if we have a matching symbol
1275 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) {
1276 if (!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) {
1277 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1278 }
1279 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1280 return true;
1281 }
1282 // no matching symbol so try for just file info
1283 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) {
1284 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1285 buf, buflen, offset, dlinfo.dli_fname)) {
1286 return true;
1287 }
1288 }
1289
1290 // Handle non-dynamic manually:
1291 if (dlinfo.dli_fbase != NULL &&
1292 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset,
1293 dlinfo.dli_fbase)) {
1294 if (!Decoder::demangle(localbuf, buf, buflen)) {
1295 jio_snprintf(buf, buflen, "%s", localbuf);
1296 }
1297 return true;
1298 }
1299 }
1300 buf[0] = '\0';
1301 if (offset != NULL) *offset = -1;
1302 return false;
1303 }
1304
1305 // ported from solaris version
1306 bool os::dll_address_to_library_name(address addr, char* buf,
1307 int buflen, int* offset) {
1308 // buf is not optional, but offset is optional
1309 assert(buf != NULL, "sanity check");
1310
1311 Dl_info dlinfo;
1312
1313 if (dladdr((void*)addr, &dlinfo) != 0) {
1314 if (dlinfo.dli_fname != NULL) {
1315 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1316 }
1317 if (dlinfo.dli_fbase != NULL && offset != NULL) {
1318 *offset = addr - (address)dlinfo.dli_fbase;
1319 }
1320 return true;
1321 }
1322
1323 buf[0] = '\0';
1324 if (offset) *offset = -1;
1325 return false;
1326 }
1327
1328 // Loads .dll/.so and
1329 // in case of error it checks if .dll/.so was built for the
1330 // same architecture as Hotspot is running on
1331
1332 #ifdef __APPLE__
1333 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1334 void * result= ::dlopen(filename, RTLD_LAZY);
1335 if (result != NULL) {
1336 // Successful loading
1337 return result;
1338 }
1339
1340 // Read system error message into ebuf
1341 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1342 ebuf[ebuflen-1]='\0';
1343
1344 return NULL;
1345 }
1346 #else
1347 void * os::dll_load(const char *filename, char *ebuf, int ebuflen)
1348 {
1349 void * result= ::dlopen(filename, RTLD_LAZY);
1350 if (result != NULL) {
1351 // Successful loading
1352 return result;
1353 }
1354
1355 Elf32_Ehdr elf_head;
1356
1357 // Read system error message into ebuf
1358 // It may or may not be overwritten below
1359 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1360 ebuf[ebuflen-1]='\0';
1361 int diag_msg_max_length=ebuflen-strlen(ebuf);
1362 char* diag_msg_buf=ebuf+strlen(ebuf);
1363
1364 if (diag_msg_max_length==0) {
1365 // No more space in ebuf for additional diagnostics message
1366 return NULL;
1367 }
1368
1369
1370 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1371
1372 if (file_descriptor < 0) {
1373 // Can't open library, report dlerror() message
1374 return NULL;
1375 }
1376
1377 bool failed_to_read_elf_head=
1378 (sizeof(elf_head)!=
1379 (::read(file_descriptor, &elf_head,sizeof(elf_head)))) ;
1380
1381 ::close(file_descriptor);
1382 if (failed_to_read_elf_head) {
1383 // file i/o error - report dlerror() msg
1384 return NULL;
1385 }
1386
1387 typedef struct {
1388 Elf32_Half code; // Actual value as defined in elf.h
1389 Elf32_Half compat_class; // Compatibility of archs at VM's sense
1390 char elf_class; // 32 or 64 bit
1391 char endianess; // MSB or LSB
1392 char* name; // String representation
1393 } arch_t;
1394
1395 #ifndef EM_486
1396 #define EM_486 6 /* Intel 80486 */
1397 #endif
1398
1399 #ifndef EM_MIPS_RS3_LE
1400 #define EM_MIPS_RS3_LE 10 /* MIPS */
1401 #endif
1402
1403 #ifndef EM_PPC64
1404 #define EM_PPC64 21 /* PowerPC64 */
1405 #endif
1406
1407 #ifndef EM_S390
1408 #define EM_S390 22 /* IBM System/390 */
1409 #endif
1410
1411 #ifndef EM_IA_64
1412 #define EM_IA_64 50 /* HP/Intel IA-64 */
1413 #endif
1414
1415 #ifndef EM_X86_64
1416 #define EM_X86_64 62 /* AMD x86-64 */
1417 #endif
1418
1419 static const arch_t arch_array[]={
1420 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1421 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1422 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
1423 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
1424 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1425 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1426 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
1427 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
1428 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
1429 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"},
1430 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
1431 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
1432 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
1433 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
1434 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
1435 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
1436 };
1437
1438 #if (defined IA32)
1439 static Elf32_Half running_arch_code=EM_386;
1440 #elif (defined AMD64)
1441 static Elf32_Half running_arch_code=EM_X86_64;
1442 #elif (defined IA64)
1443 static Elf32_Half running_arch_code=EM_IA_64;
1444 #elif (defined __sparc) && (defined _LP64)
1445 static Elf32_Half running_arch_code=EM_SPARCV9;
1446 #elif (defined __sparc) && (!defined _LP64)
1447 static Elf32_Half running_arch_code=EM_SPARC;
1448 #elif (defined __powerpc64__)
1449 static Elf32_Half running_arch_code=EM_PPC64;
1450 #elif (defined __powerpc__)
1451 static Elf32_Half running_arch_code=EM_PPC;
1452 #elif (defined ARM)
1453 static Elf32_Half running_arch_code=EM_ARM;
1454 #elif (defined S390)
1455 static Elf32_Half running_arch_code=EM_S390;
1456 #elif (defined ALPHA)
1457 static Elf32_Half running_arch_code=EM_ALPHA;
1458 #elif (defined MIPSEL)
1459 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
1460 #elif (defined PARISC)
1461 static Elf32_Half running_arch_code=EM_PARISC;
1462 #elif (defined MIPS)
1463 static Elf32_Half running_arch_code=EM_MIPS;
1464 #elif (defined M68K)
1465 static Elf32_Half running_arch_code=EM_68K;
1466 #else
1467 #error Method os::dll_load requires that one of following is defined:\
1468 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
1469 #endif
1470
1471 // Identify compatability class for VM's architecture and library's architecture
1472 // Obtain string descriptions for architectures
1473
1474 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
1475 int running_arch_index=-1;
1476
1477 for (unsigned int i=0 ; i < ARRAY_SIZE(arch_array) ; i++ ) {
1478 if (running_arch_code == arch_array[i].code) {
1479 running_arch_index = i;
1480 }
1481 if (lib_arch.code == arch_array[i].code) {
1482 lib_arch.compat_class = arch_array[i].compat_class;
1483 lib_arch.name = arch_array[i].name;
1484 }
1485 }
1486
1487 assert(running_arch_index != -1,
1488 "Didn't find running architecture code (running_arch_code) in arch_array");
1489 if (running_arch_index == -1) {
1490 // Even though running architecture detection failed
1491 // we may still continue with reporting dlerror() message
1492 return NULL;
1493 }
1494
1495 if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
1496 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
1497 return NULL;
1498 }
1499
1500 #ifndef S390
1501 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
1502 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
1503 return NULL;
1504 }
1505 #endif // !S390
1506
1507 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
1508 if ( lib_arch.name!=NULL ) {
1509 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1510 " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
1511 lib_arch.name, arch_array[running_arch_index].name);
1512 } else {
1513 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1514 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
1515 lib_arch.code,
1516 arch_array[running_arch_index].name);
1517 }
1518 }
1519
1520 return NULL;
1521 }
1522 #endif /* !__APPLE__ */
1523
1524 // XXX: Do we need a lock around this as per Linux?
1525 void* os::dll_lookup(void* handle, const char* name) {
1526 return dlsym(handle, name);
1527 }
1528
1529
1530 static bool _print_ascii_file(const char* filename, outputStream* st) {
1531 int fd = ::open(filename, O_RDONLY);
1532 if (fd == -1) {
1533 return false;
1534 }
1535
1536 char buf[32];
1537 int bytes;
1538 while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) {
1539 st->print_raw(buf, bytes);
1540 }
1541
1542 ::close(fd);
1543
1544 return true;
1545 }
1546
1547 void os::print_dll_info(outputStream *st) {
1548 st->print_cr("Dynamic libraries:");
1549 #ifdef RTLD_DI_LINKMAP
1550 Dl_info dli;
1551 void *handle;
1552 Link_map *map;
1553 Link_map *p;
1554
1555 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 ||
1556 dli.dli_fname == NULL) {
1557 st->print_cr("Error: Cannot print dynamic libraries.");
1558 return;
1559 }
1560 handle = dlopen(dli.dli_fname, RTLD_LAZY);
1561 if (handle == NULL) {
1562 st->print_cr("Error: Cannot print dynamic libraries.");
1563 return;
1564 }
1565 dlinfo(handle, RTLD_DI_LINKMAP, &map);
1566 if (map == NULL) {
1567 st->print_cr("Error: Cannot print dynamic libraries.");
1568 return;
1569 }
1570
1571 while (map->l_prev != NULL)
1572 map = map->l_prev;
1573
1574 while (map != NULL) {
1575 st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name);
1576 map = map->l_next;
1577 }
1578
1579 dlclose(handle);
1580 #elif defined(__APPLE__)
1581 uint32_t count;
1582 uint32_t i;
1583
1584 count = _dyld_image_count();
1585 for (i = 1; i < count; i++) {
1586 const char *name = _dyld_get_image_name(i);
1587 intptr_t slide = _dyld_get_image_vmaddr_slide(i);
1588 st->print_cr(PTR_FORMAT " \t%s", slide, name);
1589 }
1590 #else
1591 st->print_cr("Error: Cannot print dynamic libraries.");
1592 #endif
1593 }
1594
1595 void os::print_os_info_brief(outputStream* st) {
1596 st->print("Bsd");
1597
1598 os::Posix::print_uname_info(st);
1599 }
1600
1601 void os::print_os_info(outputStream* st) {
1602 st->print("OS:");
1603 st->print("Bsd");
1604
1605 os::Posix::print_uname_info(st);
1606
1607 os::Posix::print_rlimit_info(st);
1608
1609 os::Posix::print_load_average(st);
1610 }
1611
1612 void os::pd_print_cpu_info(outputStream* st) {
1613 // Nothing to do for now.
1614 }
1615
1616 void os::print_memory_info(outputStream* st) {
1617
1618 st->print("Memory:");
1619 st->print(" %dk page", os::vm_page_size()>>10);
1620
1621 st->print(", physical " UINT64_FORMAT "k",
1622 os::physical_memory() >> 10);
1623 st->print("(" UINT64_FORMAT "k free)",
1624 os::available_memory() >> 10);
1625 st->cr();
1626
1627 // meminfo
1628 st->print("\n/proc/meminfo:\n");
1629 _print_ascii_file("/proc/meminfo", st);
1630 st->cr();
1631 }
1632
1633 // Taken from /usr/include/bits/siginfo.h Supposed to be architecture specific
1634 // but they're the same for all the bsd arch that we support
1635 // and they're the same for solaris but there's no common place to put this.
1636 const char *ill_names[] = { "ILL0", "ILL_ILLOPC", "ILL_ILLOPN", "ILL_ILLADR",
1637 "ILL_ILLTRP", "ILL_PRVOPC", "ILL_PRVREG",
1638 "ILL_COPROC", "ILL_BADSTK" };
1639
1640 const char *fpe_names[] = { "FPE0", "FPE_INTDIV", "FPE_INTOVF", "FPE_FLTDIV",
1641 "FPE_FLTOVF", "FPE_FLTUND", "FPE_FLTRES",
1642 "FPE_FLTINV", "FPE_FLTSUB", "FPE_FLTDEN" };
1643
1644 const char *segv_names[] = { "SEGV0", "SEGV_MAPERR", "SEGV_ACCERR" };
1645
1646 const char *bus_names[] = { "BUS0", "BUS_ADRALN", "BUS_ADRERR", "BUS_OBJERR" };
1647
1648 void os::print_siginfo(outputStream* st, void* siginfo) {
1649 st->print("siginfo:");
1650
1651 const int buflen = 100;
1652 char buf[buflen];
1653 siginfo_t *si = (siginfo_t*)siginfo;
1654 st->print("si_signo=%s: ", os::exception_name(si->si_signo, buf, buflen));
1655 if (si->si_errno != 0 && strerror_r(si->si_errno, buf, buflen) == 0) {
1656 st->print("si_errno=%s", buf);
1657 } else {
1658 st->print("si_errno=%d", si->si_errno);
1659 }
1660 const int c = si->si_code;
1661 assert(c > 0, "unexpected si_code");
1662 switch (si->si_signo) {
1663 case SIGILL:
1664 st->print(", si_code=%d (%s)", c, c > 8 ? "" : ill_names[c]);
1665 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1666 break;
1667 case SIGFPE:
1668 st->print(", si_code=%d (%s)", c, c > 9 ? "" : fpe_names[c]);
1669 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1670 break;
1671 case SIGSEGV:
1672 st->print(", si_code=%d (%s)", c, c > 2 ? "" : segv_names[c]);
1673 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1674 break;
1675 case SIGBUS:
1676 st->print(", si_code=%d (%s)", c, c > 3 ? "" : bus_names[c]);
1677 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1678 break;
1679 default:
1680 st->print(", si_code=%d", si->si_code);
1681 // no si_addr
1682 }
1683
1684 if ((si->si_signo == SIGBUS || si->si_signo == SIGSEGV) &&
1685 UseSharedSpaces) {
1686 FileMapInfo* mapinfo = FileMapInfo::current_info();
1687 if (mapinfo->is_in_shared_space(si->si_addr)) {
1688 st->print("\n\nError accessing class data sharing archive." \
1689 " Mapped file inaccessible during execution, " \
1690 " possible disk/network problem.");
1691 }
1692 }
1693 st->cr();
1694 }
1695
1696
1697 static void print_signal_handler(outputStream* st, int sig,
1698 char* buf, size_t buflen);
1699
1700 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1701 st->print_cr("Signal Handlers:");
1702 print_signal_handler(st, SIGSEGV, buf, buflen);
1703 print_signal_handler(st, SIGBUS , buf, buflen);
1704 print_signal_handler(st, SIGFPE , buf, buflen);
1705 print_signal_handler(st, SIGPIPE, buf, buflen);
1706 print_signal_handler(st, SIGXFSZ, buf, buflen);
1707 print_signal_handler(st, SIGILL , buf, buflen);
1708 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen);
1709 print_signal_handler(st, SR_signum, buf, buflen);
1710 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1711 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1712 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1713 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1714 }
1715
1716 static char saved_jvm_path[MAXPATHLEN] = {0};
1717
1718 // Find the full path to the current module, libjvm
1719 void os::jvm_path(char *buf, jint buflen) {
1720 // Error checking.
1721 if (buflen < MAXPATHLEN) {
1722 assert(false, "must use a large-enough buffer");
1723 buf[0] = '\0';
1724 return;
1725 }
1726 // Lazy resolve the path to current module.
1727 if (saved_jvm_path[0] != 0) {
1728 strcpy(buf, saved_jvm_path);
1729 return;
1730 }
1731
1732 char dli_fname[MAXPATHLEN];
1733 bool ret = dll_address_to_library_name(
1734 CAST_FROM_FN_PTR(address, os::jvm_path),
1735 dli_fname, sizeof(dli_fname), NULL);
1736 assert(ret, "cannot locate libjvm");
1737 char *rp = NULL;
1738 if (ret && dli_fname[0] != '\0') {
1739 rp = realpath(dli_fname, buf);
1740 }
1741 if (rp == NULL)
1742 return;
1743
1744 if (Arguments::created_by_gamma_launcher()) {
1745 // Support for the gamma launcher. Typical value for buf is
1746 // "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm". If "/jre/lib/" appears at
1747 // the right place in the string, then assume we are installed in a JDK and
1748 // we're done. Otherwise, check for a JAVA_HOME environment variable and
1749 // construct a path to the JVM being overridden.
1750
1751 const char *p = buf + strlen(buf) - 1;
1752 for (int count = 0; p > buf && count < 5; ++count) {
1753 for (--p; p > buf && *p != '/'; --p)
1754 /* empty */ ;
1755 }
1756
1757 if (strncmp(p, "/jre/lib/", 9) != 0) {
1758 // Look for JAVA_HOME in the environment.
1759 char* java_home_var = ::getenv("JAVA_HOME");
1760 if (java_home_var != NULL && java_home_var[0] != 0) {
1761 char* jrelib_p;
1762 int len;
1763
1764 // Check the current module name "libjvm"
1765 p = strrchr(buf, '/');
1766 assert(strstr(p, "/libjvm") == p, "invalid library name");
1767
1768 rp = realpath(java_home_var, buf);
1769 if (rp == NULL)
1770 return;
1771
1772 // determine if this is a legacy image or modules image
1773 // modules image doesn't have "jre" subdirectory
1774 len = strlen(buf);
1775 jrelib_p = buf + len;
1776
1777 // Add the appropriate library subdir
1778 snprintf(jrelib_p, buflen-len, "/jre/lib");
1779 if (0 != access(buf, F_OK)) {
1780 snprintf(jrelib_p, buflen-len, "/lib");
1781 }
1782
1783 // Add the appropriate client or server subdir
1784 len = strlen(buf);
1785 jrelib_p = buf + len;
1786 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
1787 if (0 != access(buf, F_OK)) {
1788 snprintf(jrelib_p, buflen-len, "");
1789 }
1790
1791 // If the path exists within JAVA_HOME, add the JVM library name
1792 // to complete the path to JVM being overridden. Otherwise fallback
1793 // to the path to the current library.
1794 if (0 == access(buf, F_OK)) {
1795 // Use current module name "libjvm"
1796 len = strlen(buf);
1797 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
1798 } else {
1799 // Fall back to path of current library
1800 rp = realpath(dli_fname, buf);
1801 if (rp == NULL)
1802 return;
1803 }
1804 }
1805 }
1806 }
1807
1808 strcpy(saved_jvm_path, buf);
1809 }
1810
1811 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1812 // no prefix required, not even "_"
1813 }
1814
1815 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1816 // no suffix required
1817 }
1818
1819 ////////////////////////////////////////////////////////////////////////////////
1820 // sun.misc.Signal support
1821
1822 static volatile jint sigint_count = 0;
1823
1824 static void
1825 UserHandler(int sig, void *siginfo, void *context) {
1826 // 4511530 - sem_post is serialized and handled by the manager thread. When
1827 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
1828 // don't want to flood the manager thread with sem_post requests.
1829 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1)
1830 return;
1831
1832 // Ctrl-C is pressed during error reporting, likely because the error
1833 // handler fails to abort. Let VM die immediately.
1834 if (sig == SIGINT && is_error_reported()) {
1835 os::die();
1836 }
1837
1838 os::signal_notify(sig);
1839 }
1840
1841 void* os::user_handler() {
1842 return CAST_FROM_FN_PTR(void*, UserHandler);
1843 }
1844
1845 extern "C" {
1846 typedef void (*sa_handler_t)(int);
1847 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1848 }
1849
1850 void* os::signal(int signal_number, void* handler) {
1851 struct sigaction sigAct, oldSigAct;
1852
1853 sigfillset(&(sigAct.sa_mask));
1854 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
1855 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1856
1857 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1858 // -1 means registration failed
1859 return (void *)-1;
1860 }
1861
1862 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1863 }
1864
1865 void os::signal_raise(int signal_number) {
1866 ::raise(signal_number);
1867 }
1868
1869 /*
1870 * The following code is moved from os.cpp for making this
1871 * code platform specific, which it is by its very nature.
1872 */
1873
1874 // Will be modified when max signal is changed to be dynamic
1875 int os::sigexitnum_pd() {
1876 return NSIG;
1877 }
1878
1879 // a counter for each possible signal value
1880 static volatile jint pending_signals[NSIG+1] = { 0 };
1881
1882 // Bsd(POSIX) specific hand shaking semaphore.
1883 #ifdef __APPLE__
1884 typedef semaphore_t os_semaphore_t;
1885 #define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value)
1886 #define SEM_WAIT(sem) semaphore_wait(sem)
1887 #define SEM_POST(sem) semaphore_signal(sem)
1888 #define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem)
1889 #else
1890 typedef sem_t os_semaphore_t;
1891 #define SEM_INIT(sem, value) sem_init(&sem, 0, value)
1892 #define SEM_WAIT(sem) sem_wait(&sem)
1893 #define SEM_POST(sem) sem_post(&sem)
1894 #define SEM_DESTROY(sem) sem_destroy(&sem)
1895 #endif
1896
1897 class Semaphore : public StackObj {
1898 public:
1899 Semaphore();
1900 ~Semaphore();
1901 void signal();
1902 void wait();
1903 bool trywait();
1904 bool timedwait(unsigned int sec, int nsec);
1905 private:
1906 jlong currenttime() const;
1907 semaphore_t _semaphore;
1908 };
1909
1910 Semaphore::Semaphore() : _semaphore(0) {
1911 SEM_INIT(_semaphore, 0);
1912 }
1913
1914 Semaphore::~Semaphore() {
1915 SEM_DESTROY(_semaphore);
1916 }
1917
1918 void Semaphore::signal() {
1919 SEM_POST(_semaphore);
1920 }
1921
1922 void Semaphore::wait() {
1923 SEM_WAIT(_semaphore);
1924 }
1925
1926 jlong Semaphore::currenttime() const {
1927 struct timeval tv;
1928 gettimeofday(&tv, NULL);
1929 return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000);
1930 }
1931
1932 #ifdef __APPLE__
1933 bool Semaphore::trywait() {
1934 return timedwait(0, 0);
1935 }
1936
1937 bool Semaphore::timedwait(unsigned int sec, int nsec) {
1938 kern_return_t kr = KERN_ABORTED;
1939 mach_timespec_t waitspec;
1940 waitspec.tv_sec = sec;
1941 waitspec.tv_nsec = nsec;
1942
1943 jlong starttime = currenttime();
1944
1945 kr = semaphore_timedwait(_semaphore, waitspec);
1946 while (kr == KERN_ABORTED) {
1947 jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec;
1948
1949 jlong current = currenttime();
1950 jlong passedtime = current - starttime;
1951
1952 if (passedtime >= totalwait) {
1953 waitspec.tv_sec = 0;
1954 waitspec.tv_nsec = 0;
1955 } else {
1956 jlong waittime = totalwait - (current - starttime);
1957 waitspec.tv_sec = waittime / NANOSECS_PER_SEC;
1958 waitspec.tv_nsec = waittime % NANOSECS_PER_SEC;
1959 }
1960
1961 kr = semaphore_timedwait(_semaphore, waitspec);
1962 }
1963
1964 return kr == KERN_SUCCESS;
1965 }
1966
1967 #else
1968
1969 bool Semaphore::trywait() {
1970 return sem_trywait(&_semaphore) == 0;
1971 }
1972
1973 bool Semaphore::timedwait(unsigned int sec, int nsec) {
1974 struct timespec ts;
1975 jlong endtime = unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec);
1976
1977 while (1) {
1978 int result = sem_timedwait(&_semaphore, &ts);
1979 if (result == 0) {
1980 return true;
1981 } else if (errno == EINTR) {
1982 continue;
1983 } else if (errno == ETIMEDOUT) {
1984 return false;
1985 } else {
1986 return false;
1987 }
1988 }
1989 }
1990
1991 #endif // __APPLE__
1992
1993 static os_semaphore_t sig_sem;
1994 static Semaphore sr_semaphore;
1995
1996 void os::signal_init_pd() {
1997 // Initialize signal structures
1998 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
1999
2000 // Initialize signal semaphore
2001 ::SEM_INIT(sig_sem, 0);
2002 }
2003
2004 void os::signal_notify(int sig) {
2005 Atomic::inc(&pending_signals[sig]);
2006 ::SEM_POST(sig_sem);
2007 }
2008
2009 static int check_pending_signals(bool wait) {
2010 Atomic::store(0, &sigint_count);
2011 for (;;) {
2012 for (int i = 0; i < NSIG + 1; i++) {
2013 jint n = pending_signals[i];
2014 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
2015 return i;
2016 }
2017 }
2018 if (!wait) {
2019 return -1;
2020 }
2021 JavaThread *thread = JavaThread::current();
2022 ThreadBlockInVM tbivm(thread);
2023
2024 bool threadIsSuspended;
2025 do {
2026 thread->set_suspend_equivalent();
2027 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
2028 ::SEM_WAIT(sig_sem);
2029
2030 // were we externally suspended while we were waiting?
2031 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
2032 if (threadIsSuspended) {
2033 //
2034 // The semaphore has been incremented, but while we were waiting
2035 // another thread suspended us. We don't want to continue running
2036 // while suspended because that would surprise the thread that
2037 // suspended us.
2038 //
2039 ::SEM_POST(sig_sem);
2040
2041 thread->java_suspend_self();
2042 }
2043 } while (threadIsSuspended);
2044 }
2045 }
2046
2047 int os::signal_lookup() {
2048 return check_pending_signals(false);
2049 }
2050
2051 int os::signal_wait() {
2052 return check_pending_signals(true);
2053 }
2054
2055 ////////////////////////////////////////////////////////////////////////////////
2056 // Virtual Memory
2057
2058 int os::vm_page_size() {
2059 // Seems redundant as all get out
2060 assert(os::Bsd::page_size() != -1, "must call os::init");
2061 return os::Bsd::page_size();
2062 }
2063
2064 // Solaris allocates memory by pages.
2065 int os::vm_allocation_granularity() {
2066 assert(os::Bsd::page_size() != -1, "must call os::init");
2067 return os::Bsd::page_size();
2068 }
2069
2070 // Rationale behind this function:
2071 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
2072 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
2073 // samples for JITted code. Here we create private executable mapping over the code cache
2074 // and then we can use standard (well, almost, as mapping can change) way to provide
2075 // info for the reporting script by storing timestamp and location of symbol
2076 void bsd_wrap_code(char* base, size_t size) {
2077 static volatile jint cnt = 0;
2078
2079 if (!UseOprofile) {
2080 return;
2081 }
2082
2083 char buf[PATH_MAX + 1];
2084 int num = Atomic::add(1, &cnt);
2085
2086 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
2087 os::get_temp_directory(), os::current_process_id(), num);
2088 unlink(buf);
2089
2090 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
2091
2092 if (fd != -1) {
2093 off_t rv = ::lseek(fd, size-2, SEEK_SET);
2094 if (rv != (off_t)-1) {
2095 if (::write(fd, "", 1) == 1) {
2096 mmap(base, size,
2097 PROT_READ|PROT_WRITE|PROT_EXEC,
2098 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
2099 }
2100 }
2101 ::close(fd);
2102 unlink(buf);
2103 }
2104 }
2105
2106 static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
2107 int err) {
2108 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT
2109 ", %d) failed; error='%s' (errno=%d)", addr, size, exec,
2110 strerror(err), err);
2111 }
2112
2113 // NOTE: Bsd kernel does not really reserve the pages for us.
2114 // All it does is to check if there are enough free pages
2115 // left at the time of mmap(). This could be a potential
2116 // problem.
2117 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
2118 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
2119 #ifdef __OpenBSD__
2120 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2121 if (::mprotect(addr, size, prot) == 0) {
2122 return true;
2123 }
2124 #else
2125 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
2126 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
2127 if (res != (uintptr_t) MAP_FAILED) {
2128 return true;
2129 }
2130 #endif
2131
2132 // Warn about any commit errors we see in non-product builds just
2133 // in case mmap() doesn't work as described on the man page.
2134 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);)
2135
2136 return false;
2137 }
2138
2139 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
2140 bool exec) {
2141 // alignment_hint is ignored on this OS
2142 return pd_commit_memory(addr, size, exec);
2143 }
2144
2145 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
2146 const char* mesg) {
2147 assert(mesg != NULL, "mesg must be specified");
2148 if (!pd_commit_memory(addr, size, exec)) {
2149 // add extra info in product mode for vm_exit_out_of_memory():
2150 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
2151 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, mesg);
2152 }
2153 }
2154
2155 void os::pd_commit_memory_or_exit(char* addr, size_t size,
2156 size_t alignment_hint, bool exec,
2157 const char* mesg) {
2158 // alignment_hint is ignored on this OS
2159 pd_commit_memory_or_exit(addr, size, exec, mesg);
2160 }
2161
2162 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
2163 }
2164
2165 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
2166 ::madvise(addr, bytes, MADV_DONTNEED);
2167 }
2168
2169 void os::numa_make_global(char *addr, size_t bytes) {
2170 }
2171
2172 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
2173 }
2174
2175 bool os::numa_topology_changed() { return false; }
2176
2177 size_t os::numa_get_groups_num() {
2178 return 1;
2179 }
2180
2181 int os::numa_get_group_id() {
2182 return 0;
2183 }
2184
2185 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
2186 if (size > 0) {
2187 ids[0] = 0;
2188 return 1;
2189 }
2190 return 0;
2191 }
2192
2193 bool os::get_page_info(char *start, page_info* info) {
2194 return false;
2195 }
2196
2197 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2198 return end;
2199 }
2200
2201
2202 bool os::pd_uncommit_memory(char* addr, size_t size) {
2203 #ifdef __OpenBSD__
2204 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2205 return ::mprotect(addr, size, PROT_NONE) == 0;
2206 #else
2207 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
2208 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
2209 return res != (uintptr_t) MAP_FAILED;
2210 #endif
2211 }
2212
2213 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2214 return os::commit_memory(addr, size, !ExecMem);
2215 }
2216
2217 // If this is a growable mapping, remove the guard pages entirely by
2218 // munmap()ping them. If not, just call uncommit_memory().
2219 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2220 return os::uncommit_memory(addr, size);
2221 }
2222
2223 static address _highest_vm_reserved_address = NULL;
2224
2225 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2226 // at 'requested_addr'. If there are existing memory mappings at the same
2227 // location, however, they will be overwritten. If 'fixed' is false,
2228 // 'requested_addr' is only treated as a hint, the return value may or
2229 // may not start from the requested address. Unlike Bsd mmap(), this
2230 // function returns NULL to indicate failure.
2231 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2232 char * addr;
2233 int flags;
2234
2235 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2236 if (fixed) {
2237 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2238 flags |= MAP_FIXED;
2239 }
2240
2241 // Map reserved/uncommitted pages PROT_NONE so we fail early if we
2242 // touch an uncommitted page. Otherwise, the read/write might
2243 // succeed if we have enough swap space to back the physical page.
2244 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE,
2245 flags, -1, 0);
2246
2247 if (addr != MAP_FAILED) {
2248 // anon_mmap() should only get called during VM initialization,
2249 // don't need lock (actually we can skip locking even it can be called
2250 // from multiple threads, because _highest_vm_reserved_address is just a
2251 // hint about the upper limit of non-stack memory regions.)
2252 if ((address)addr + bytes > _highest_vm_reserved_address) {
2253 _highest_vm_reserved_address = (address)addr + bytes;
2254 }
2255 }
2256
2257 return addr == MAP_FAILED ? NULL : addr;
2258 }
2259
2260 // Don't update _highest_vm_reserved_address, because there might be memory
2261 // regions above addr + size. If so, releasing a memory region only creates
2262 // a hole in the address space, it doesn't help prevent heap-stack collision.
2263 //
2264 static int anon_munmap(char * addr, size_t size) {
2265 return ::munmap(addr, size) == 0;
2266 }
2267
2268 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
2269 size_t alignment_hint) {
2270 return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2271 }
2272
2273 bool os::pd_release_memory(char* addr, size_t size) {
2274 return anon_munmap(addr, size);
2275 }
2276
2277 static bool bsd_mprotect(char* addr, size_t size, int prot) {
2278 // Bsd wants the mprotect address argument to be page aligned.
2279 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size());
2280
2281 // According to SUSv3, mprotect() should only be used with mappings
2282 // established by mmap(), and mmap() always maps whole pages. Unaligned
2283 // 'addr' likely indicates problem in the VM (e.g. trying to change
2284 // protection of malloc'ed or statically allocated memory). Check the
2285 // caller if you hit this assert.
2286 assert(addr == bottom, "sanity check");
2287
2288 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2289 return ::mprotect(bottom, size, prot) == 0;
2290 }
2291
2292 // Set protections specified
2293 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2294 bool is_committed) {
2295 unsigned int p = 0;
2296 switch (prot) {
2297 case MEM_PROT_NONE: p = PROT_NONE; break;
2298 case MEM_PROT_READ: p = PROT_READ; break;
2299 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
2300 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2301 default:
2302 ShouldNotReachHere();
2303 }
2304 // is_committed is unused.
2305 return bsd_mprotect(addr, bytes, p);
2306 }
2307
2308 bool os::guard_memory(char* addr, size_t size) {
2309 return bsd_mprotect(addr, size, PROT_NONE);
2310 }
2311
2312 bool os::unguard_memory(char* addr, size_t size) {
2313 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
2314 }
2315
2316 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
2317 return false;
2318 }
2319
2320 // Large page support
2321
2322 static size_t _large_page_size = 0;
2323
2324 void os::large_page_init() {
2325 }
2326
2327
2328 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) {
2329 fatal("This code is not used or maintained.");
2330
2331 // "exec" is passed in but not used. Creating the shared image for
2332 // the code cache doesn't have an SHM_X executable permission to check.
2333 assert(UseLargePages && UseSHM, "only for SHM large pages");
2334
2335 key_t key = IPC_PRIVATE;
2336 char *addr;
2337
2338 bool warn_on_failure = UseLargePages &&
2339 (!FLAG_IS_DEFAULT(UseLargePages) ||
2340 !FLAG_IS_DEFAULT(LargePageSizeInBytes)
2341 );
2342 char msg[128];
2343
2344 // Create a large shared memory region to attach to based on size.
2345 // Currently, size is the total size of the heap
2346 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W);
2347 if (shmid == -1) {
2348 // Possible reasons for shmget failure:
2349 // 1. shmmax is too small for Java heap.
2350 // > check shmmax value: cat /proc/sys/kernel/shmmax
2351 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax
2352 // 2. not enough large page memory.
2353 // > check available large pages: cat /proc/meminfo
2354 // > increase amount of large pages:
2355 // echo new_value > /proc/sys/vm/nr_hugepages
2356 // Note 1: different Bsd may use different name for this property,
2357 // e.g. on Redhat AS-3 it is "hugetlb_pool".
2358 // Note 2: it's possible there's enough physical memory available but
2359 // they are so fragmented after a long run that they can't
2360 // coalesce into large pages. Try to reserve large pages when
2361 // the system is still "fresh".
2362 if (warn_on_failure) {
2363 jio_snprintf(msg, sizeof(msg), "Failed to reserve shared memory (errno = %d).", errno);
2364 warning(msg);
2365 }
2366 return NULL;
2367 }
2368
2369 // attach to the region
2370 addr = (char*)shmat(shmid, req_addr, 0);
2371 int err = errno;
2372
2373 // Remove shmid. If shmat() is successful, the actual shared memory segment
2374 // will be deleted when it's detached by shmdt() or when the process
2375 // terminates. If shmat() is not successful this will remove the shared
2376 // segment immediately.
2377 shmctl(shmid, IPC_RMID, NULL);
2378
2379 if ((intptr_t)addr == -1) {
2380 if (warn_on_failure) {
2381 jio_snprintf(msg, sizeof(msg), "Failed to attach shared memory (errno = %d).", err);
2382 warning(msg);
2383 }
2384 return NULL;
2385 }
2386
2387 // The memory is committed
2388 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, mtNone, CALLER_PC);
2389
2390 return addr;
2391 }
2392
2393 bool os::release_memory_special(char* base, size_t bytes) {
2394 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
2395 // detaching the SHM segment will also delete it, see reserve_memory_special()
2396 int rslt = shmdt(base);
2397 if (rslt == 0) {
2398 tkr.record((address)base, bytes);
2399 return true;
2400 } else {
2401 tkr.discard();
2402 return false;
2403 }
2404
2405 }
2406
2407 size_t os::large_page_size() {
2408 return _large_page_size;
2409 }
2410
2411 // HugeTLBFS allows application to commit large page memory on demand;
2412 // with SysV SHM the entire memory region must be allocated as shared
2413 // memory.
2414 bool os::can_commit_large_page_memory() {
2415 return UseHugeTLBFS;
2416 }
2417
2418 bool os::can_execute_large_page_memory() {
2419 return UseHugeTLBFS;
2420 }
2421
2422 // Reserve memory at an arbitrary address, only if that area is
2423 // available (and not reserved for something else).
2424
2425 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2426 const int max_tries = 10;
2427 char* base[max_tries];
2428 size_t size[max_tries];
2429 const size_t gap = 0x000000;
2430
2431 // Assert only that the size is a multiple of the page size, since
2432 // that's all that mmap requires, and since that's all we really know
2433 // about at this low abstraction level. If we need higher alignment,
2434 // we can either pass an alignment to this method or verify alignment
2435 // in one of the methods further up the call chain. See bug 5044738.
2436 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2437
2438 // Repeatedly allocate blocks until the block is allocated at the
2439 // right spot. Give up after max_tries. Note that reserve_memory() will
2440 // automatically update _highest_vm_reserved_address if the call is
2441 // successful. The variable tracks the highest memory address every reserved
2442 // by JVM. It is used to detect heap-stack collision if running with
2443 // fixed-stack BsdThreads. Because here we may attempt to reserve more
2444 // space than needed, it could confuse the collision detecting code. To
2445 // solve the problem, save current _highest_vm_reserved_address and
2446 // calculate the correct value before return.
2447 address old_highest = _highest_vm_reserved_address;
2448
2449 // Bsd mmap allows caller to pass an address as hint; give it a try first,
2450 // if kernel honors the hint then we can return immediately.
2451 char * addr = anon_mmap(requested_addr, bytes, false);
2452 if (addr == requested_addr) {
2453 return requested_addr;
2454 }
2455
2456 if (addr != NULL) {
2457 // mmap() is successful but it fails to reserve at the requested address
2458 anon_munmap(addr, bytes);
2459 }
2460
2461 int i;
2462 for (i = 0; i < max_tries; ++i) {
2463 base[i] = reserve_memory(bytes);
2464
2465 if (base[i] != NULL) {
2466 // Is this the block we wanted?
2467 if (base[i] == requested_addr) {
2468 size[i] = bytes;
2469 break;
2470 }
2471
2472 // Does this overlap the block we wanted? Give back the overlapped
2473 // parts and try again.
2474
2475 size_t top_overlap = requested_addr + (bytes + gap) - base[i];
2476 if (top_overlap >= 0 && top_overlap < bytes) {
2477 unmap_memory(base[i], top_overlap);
2478 base[i] += top_overlap;
2479 size[i] = bytes - top_overlap;
2480 } else {
2481 size_t bottom_overlap = base[i] + bytes - requested_addr;
2482 if (bottom_overlap >= 0 && bottom_overlap < bytes) {
2483 unmap_memory(requested_addr, bottom_overlap);
2484 size[i] = bytes - bottom_overlap;
2485 } else {
2486 size[i] = bytes;
2487 }
2488 }
2489 }
2490 }
2491
2492 // Give back the unused reserved pieces.
2493
2494 for (int j = 0; j < i; ++j) {
2495 if (base[j] != NULL) {
2496 unmap_memory(base[j], size[j]);
2497 }
2498 }
2499
2500 if (i < max_tries) {
2501 _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes);
2502 return requested_addr;
2503 } else {
2504 _highest_vm_reserved_address = old_highest;
2505 return NULL;
2506 }
2507 }
2508
2509 size_t os::read(int fd, void *buf, unsigned int nBytes) {
2510 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes));
2511 }
2512
2513 // TODO-FIXME: reconcile Solaris' os::sleep with the bsd variation.
2514 // Solaris uses poll(), bsd uses park().
2515 // Poll() is likely a better choice, assuming that Thread.interrupt()
2516 // generates a SIGUSRx signal. Note that SIGUSR1 can interfere with
2517 // SIGSEGV, see 4355769.
2518
2519 int os::sleep(Thread* thread, jlong millis, bool interruptible) {
2520 assert(thread == Thread::current(), "thread consistency check");
2521
2522 ParkEvent * const slp = thread->_SleepEvent ;
2523 slp->reset() ;
2524 OrderAccess::fence() ;
2525
2526 if (interruptible) {
2527 jlong prevtime = javaTimeNanos();
2528
2529 for (;;) {
2530 if (os::is_interrupted(thread, true)) {
2531 return OS_INTRPT;
2532 }
2533
2534 jlong newtime = javaTimeNanos();
2535
2536 if (newtime - prevtime < 0) {
2537 // time moving backwards, should only happen if no monotonic clock
2538 // not a guarantee() because JVM should not abort on kernel/glibc bugs
2539 assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
2540 } else {
2541 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
2542 }
2543
2544 if(millis <= 0) {
2545 return OS_OK;
2546 }
2547
2548 prevtime = newtime;
2549
2550 {
2551 assert(thread->is_Java_thread(), "sanity check");
2552 JavaThread *jt = (JavaThread *) thread;
2553 ThreadBlockInVM tbivm(jt);
2554 OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */);
2555
2556 jt->set_suspend_equivalent();
2557 // cleared by handle_special_suspend_equivalent_condition() or
2558 // java_suspend_self() via check_and_wait_while_suspended()
2559
2560 slp->park(millis);
2561
2562 // were we externally suspended while we were waiting?
2563 jt->check_and_wait_while_suspended();
2564 }
2565 }
2566 } else {
2567 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
2568 jlong prevtime = javaTimeNanos();
2569
2570 for (;;) {
2571 // It'd be nice to avoid the back-to-back javaTimeNanos() calls on
2572 // the 1st iteration ...
2573 jlong newtime = javaTimeNanos();
2574
2575 if (newtime - prevtime < 0) {
2576 // time moving backwards, should only happen if no monotonic clock
2577 // not a guarantee() because JVM should not abort on kernel/glibc bugs
2578 assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
2579 } else {
2580 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
2581 }
2582
2583 if(millis <= 0) break ;
2584
2585 prevtime = newtime;
2586 slp->park(millis);
2587 }
2588 return OS_OK ;
2589 }
2590 }
2591
2592 int os::naked_sleep() {
2593 // %% make the sleep time an integer flag. for now use 1 millisec.
2594 return os::sleep(Thread::current(), 1, false);
2595 }
2596
2597 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2598 void os::infinite_sleep() {
2599 while (true) { // sleep forever ...
2600 ::sleep(100); // ... 100 seconds at a time
2601 }
2602 }
2603
2604 // Used to convert frequent JVM_Yield() to nops
2605 bool os::dont_yield() {
2606 return DontYieldALot;
2607 }
2608
2609 void os::yield() {
2610 sched_yield();
2611 }
2612
2613 os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;}
2614
2615 void os::yield_all(int attempts) {
2616 // Yields to all threads, including threads with lower priorities
2617 // Threads on Bsd are all with same priority. The Solaris style
2618 // os::yield_all() with nanosleep(1ms) is not necessary.
2619 sched_yield();
2620 }
2621
2622 // Called from the tight loops to possibly influence time-sharing heuristics
2623 void os::loop_breaker(int attempts) {
2624 os::yield_all(attempts);
2625 }
2626
2627 ////////////////////////////////////////////////////////////////////////////////
2628 // thread priority support
2629
2630 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2631 // only supports dynamic priority, static priority must be zero. For real-time
2632 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
2633 // However, for large multi-threaded applications, SCHED_RR is not only slower
2634 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2635 // of 5 runs - Sep 2005).
2636 //
2637 // The following code actually changes the niceness of kernel-thread/LWP. It
2638 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
2639 // not the entire user process, and user level threads are 1:1 mapped to kernel
2640 // threads. It has always been the case, but could change in the future. For
2641 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2642 // It is only used when ThreadPriorityPolicy=1 and requires root privilege.
2643
2644 #if !defined(__APPLE__)
2645 int os::java_to_os_priority[CriticalPriority + 1] = {
2646 19, // 0 Entry should never be used
2647
2648 0, // 1 MinPriority
2649 3, // 2
2650 6, // 3
2651
2652 10, // 4
2653 15, // 5 NormPriority
2654 18, // 6
2655
2656 21, // 7
2657 25, // 8
2658 28, // 9 NearMaxPriority
2659
2660 31, // 10 MaxPriority
2661
2662 31 // 11 CriticalPriority
2663 };
2664 #else
2665 /* Using Mach high-level priority assignments */
2666 int os::java_to_os_priority[CriticalPriority + 1] = {
2667 0, // 0 Entry should never be used (MINPRI_USER)
2668
2669 27, // 1 MinPriority
2670 28, // 2
2671 29, // 3
2672
2673 30, // 4
2674 31, // 5 NormPriority (BASEPRI_DEFAULT)
2675 32, // 6
2676
2677 33, // 7
2678 34, // 8
2679 35, // 9 NearMaxPriority
2680
2681 36, // 10 MaxPriority
2682
2683 36 // 11 CriticalPriority
2684 };
2685 #endif
2686
2687 static int prio_init() {
2688 if (ThreadPriorityPolicy == 1) {
2689 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1
2690 // if effective uid is not root. Perhaps, a more elegant way of doing
2691 // this is to test CAP_SYS_NICE capability, but that will require libcap.so
2692 if (geteuid() != 0) {
2693 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
2694 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd");
2695 }
2696 ThreadPriorityPolicy = 0;
2697 }
2698 }
2699 if (UseCriticalJavaThreadPriority) {
2700 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2701 }
2702 return 0;
2703 }
2704
2705 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2706 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) return OS_OK;
2707
2708 #ifdef __OpenBSD__
2709 // OpenBSD pthread_setprio starves low priority threads
2710 return OS_OK;
2711 #elif defined(__FreeBSD__)
2712 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2713 #elif defined(__APPLE__) || defined(__NetBSD__)
2714 struct sched_param sp;
2715 int policy;
2716 pthread_t self = pthread_self();
2717
2718 if (pthread_getschedparam(self, &policy, &sp) != 0)
2719 return OS_ERR;
2720
2721 sp.sched_priority = newpri;
2722 if (pthread_setschedparam(self, policy, &sp) != 0)
2723 return OS_ERR;
2724
2725 return OS_OK;
2726 #else
2727 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2728 return (ret == 0) ? OS_OK : OS_ERR;
2729 #endif
2730 }
2731
2732 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2733 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) {
2734 *priority_ptr = java_to_os_priority[NormPriority];
2735 return OS_OK;
2736 }
2737
2738 errno = 0;
2739 #if defined(__OpenBSD__) || defined(__FreeBSD__)
2740 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2741 #elif defined(__APPLE__) || defined(__NetBSD__)
2742 int policy;
2743 struct sched_param sp;
2744
2745 pthread_getschedparam(pthread_self(), &policy, &sp);
2746 *priority_ptr = sp.sched_priority;
2747 #else
2748 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2749 #endif
2750 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2751 }
2752
2753 // Hint to the underlying OS that a task switch would not be good.
2754 // Void return because it's a hint and can fail.
2755 void os::hint_no_preempt() {}
2756
2757 ////////////////////////////////////////////////////////////////////////////////
2758 // suspend/resume support
2759
2760 // the low-level signal-based suspend/resume support is a remnant from the
2761 // old VM-suspension that used to be for java-suspension, safepoints etc,
2762 // within hotspot. Now there is a single use-case for this:
2763 // - calling get_thread_pc() on the VMThread by the flat-profiler task
2764 // that runs in the watcher thread.
2765 // The remaining code is greatly simplified from the more general suspension
2766 // code that used to be used.
2767 //
2768 // The protocol is quite simple:
2769 // - suspend:
2770 // - sends a signal to the target thread
2771 // - polls the suspend state of the osthread using a yield loop
2772 // - target thread signal handler (SR_handler) sets suspend state
2773 // and blocks in sigsuspend until continued
2774 // - resume:
2775 // - sets target osthread state to continue
2776 // - sends signal to end the sigsuspend loop in the SR_handler
2777 //
2778 // Note that the SR_lock plays no role in this suspend/resume protocol.
2779 //
2780
2781 static void resume_clear_context(OSThread *osthread) {
2782 osthread->set_ucontext(NULL);
2783 osthread->set_siginfo(NULL);
2784 }
2785
2786 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2787 osthread->set_ucontext(context);
2788 osthread->set_siginfo(siginfo);
2789 }
2790
2791 //
2792 // Handler function invoked when a thread's execution is suspended or
2793 // resumed. We have to be careful that only async-safe functions are
2794 // called here (Note: most pthread functions are not async safe and
2795 // should be avoided.)
2796 //
2797 // Note: sigwait() is a more natural fit than sigsuspend() from an
2798 // interface point of view, but sigwait() prevents the signal hander
2799 // from being run. libpthread would get very confused by not having
2800 // its signal handlers run and prevents sigwait()'s use with the
2801 // mutex granting granting signal.
2802 //
2803 // Currently only ever called on the VMThread or JavaThread
2804 //
2805 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2806 // Save and restore errno to avoid confusing native code with EINTR
2807 // after sigsuspend.
2808 int old_errno = errno;
2809
2810 Thread* thread = Thread::current();
2811 OSThread* osthread = thread->osthread();
2812 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
2813
2814 os::SuspendResume::State current = osthread->sr.state();
2815 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
2816 suspend_save_context(osthread, siginfo, context);
2817
2818 // attempt to switch the state, we assume we had a SUSPEND_REQUEST
2819 os::SuspendResume::State state = osthread->sr.suspended();
2820 if (state == os::SuspendResume::SR_SUSPENDED) {
2821 sigset_t suspend_set; // signals for sigsuspend()
2822
2823 // get current set of blocked signals and unblock resume signal
2824 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2825 sigdelset(&suspend_set, SR_signum);
2826
2827 sr_semaphore.signal();
2828 // wait here until we are resumed
2829 while (1) {
2830 sigsuspend(&suspend_set);
2831
2832 os::SuspendResume::State result = osthread->sr.running();
2833 if (result == os::SuspendResume::SR_RUNNING) {
2834 sr_semaphore.signal();
2835 break;
2836 } else if (result != os::SuspendResume::SR_SUSPENDED) {
2837 ShouldNotReachHere();
2838 }
2839 }
2840
2841 } else if (state == os::SuspendResume::SR_RUNNING) {
2842 // request was cancelled, continue
2843 } else {
2844 ShouldNotReachHere();
2845 }
2846
2847 resume_clear_context(osthread);
2848 } else if (current == os::SuspendResume::SR_RUNNING) {
2849 // request was cancelled, continue
2850 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
2851 // ignore
2852 } else {
2853 // ignore
2854 }
2855
2856 errno = old_errno;
2857 }
2858
2859
2860 static int SR_initialize() {
2861 struct sigaction act;
2862 char *s;
2863 /* Get signal number to use for suspend/resume */
2864 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2865 int sig = ::strtol(s, 0, 10);
2866 if (sig > 0 || sig < NSIG) {
2867 SR_signum = sig;
2868 }
2869 }
2870
2871 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2872 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2873
2874 sigemptyset(&SR_sigset);
2875 sigaddset(&SR_sigset, SR_signum);
2876
2877 /* Set up signal handler for suspend/resume */
2878 act.sa_flags = SA_RESTART|SA_SIGINFO;
2879 act.sa_handler = (void (*)(int)) SR_handler;
2880
2881 // SR_signum is blocked by default.
2882 // 4528190 - We also need to block pthread restart signal (32 on all
2883 // supported Bsd platforms). Note that BsdThreads need to block
2884 // this signal for all threads to work properly. So we don't have
2885 // to use hard-coded signal number when setting up the mask.
2886 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2887
2888 if (sigaction(SR_signum, &act, 0) == -1) {
2889 return -1;
2890 }
2891
2892 // Save signal flag
2893 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2894 return 0;
2895 }
2896
2897 static int sr_notify(OSThread* osthread) {
2898 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2899 assert_status(status == 0, status, "pthread_kill");
2900 return status;
2901 }
2902
2903 // "Randomly" selected value for how long we want to spin
2904 // before bailing out on suspending a thread, also how often
2905 // we send a signal to a thread we want to resume
2906 static const int RANDOMLY_LARGE_INTEGER = 1000000;
2907 static const int RANDOMLY_LARGE_INTEGER2 = 100;
2908
2909 // returns true on success and false on error - really an error is fatal
2910 // but this seems the normal response to library errors
2911 static bool do_suspend(OSThread* osthread) {
2912 assert(osthread->sr.is_running(), "thread should be running");
2913 assert(!sr_semaphore.trywait(), "semaphore has invalid state");
2914
2915 // mark as suspended and send signal
2916 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
2917 // failed to switch, state wasn't running?
2918 ShouldNotReachHere();
2919 return false;
2920 }
2921
2922 if (sr_notify(osthread) != 0) {
2923 ShouldNotReachHere();
2924 }
2925
2926 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
2927 while (true) {
2928 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2929 break;
2930 } else {
2931 // timeout
2932 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
2933 if (cancelled == os::SuspendResume::SR_RUNNING) {
2934 return false;
2935 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
2936 // make sure that we consume the signal on the semaphore as well
2937 sr_semaphore.wait();
2938 break;
2939 } else {
2940 ShouldNotReachHere();
2941 return false;
2942 }
2943 }
2944 }
2945
2946 guarantee(osthread->sr.is_suspended(), "Must be suspended");
2947 return true;
2948 }
2949
2950 static void do_resume(OSThread* osthread) {
2951 assert(osthread->sr.is_suspended(), "thread should be suspended");
2952 assert(!sr_semaphore.trywait(), "invalid semaphore state");
2953
2954 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
2955 // failed to switch to WAKEUP_REQUEST
2956 ShouldNotReachHere();
2957 return;
2958 }
2959
2960 while (true) {
2961 if (sr_notify(osthread) == 0) {
2962 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2963 if (osthread->sr.is_running()) {
2964 return;
2965 }
2966 }
2967 } else {
2968 ShouldNotReachHere();
2969 }
2970 }
2971
2972 guarantee(osthread->sr.is_running(), "Must be running!");
2973 }
2974
2975 ////////////////////////////////////////////////////////////////////////////////
2976 // interrupt support
2977
2978 void os::interrupt(Thread* thread) {
2979 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
2980 "possibility of dangling Thread pointer");
2981
2982 OSThread* osthread = thread->osthread();
2983
2984 if (!osthread->interrupted()) {
2985 osthread->set_interrupted(true);
2986 // More than one thread can get here with the same value of osthread,
2987 // resulting in multiple notifications. We do, however, want the store
2988 // to interrupted() to be visible to other threads before we execute unpark().
2989 OrderAccess::fence();
2990 ParkEvent * const slp = thread->_SleepEvent ;
2991 if (slp != NULL) slp->unpark() ;
2992 }
2993
2994 // For JSR166. Unpark even if interrupt status already was set
2995 if (thread->is_Java_thread())
2996 ((JavaThread*)thread)->parker()->unpark();
2997
2998 ParkEvent * ev = thread->_ParkEvent ;
2999 if (ev != NULL) ev->unpark() ;
3000
3001 }
3002
3003 bool os::is_interrupted(Thread* thread, bool clear_interrupted) {
3004 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
3005 "possibility of dangling Thread pointer");
3006
3007 OSThread* osthread = thread->osthread();
3008
3009 bool interrupted = osthread->interrupted();
3010
3011 if (interrupted && clear_interrupted) {
3012 osthread->set_interrupted(false);
3013 // consider thread->_SleepEvent->reset() ... optional optimization
3014 }
3015
3016 return interrupted;
3017 }
3018
3019 ///////////////////////////////////////////////////////////////////////////////////
3020 // signal handling (except suspend/resume)
3021
3022 // This routine may be used by user applications as a "hook" to catch signals.
3023 // The user-defined signal handler must pass unrecognized signals to this
3024 // routine, and if it returns true (non-zero), then the signal handler must
3025 // return immediately. If the flag "abort_if_unrecognized" is true, then this
3026 // routine will never retun false (zero), but instead will execute a VM panic
3027 // routine kill the process.
3028 //
3029 // If this routine returns false, it is OK to call it again. This allows
3030 // the user-defined signal handler to perform checks either before or after
3031 // the VM performs its own checks. Naturally, the user code would be making
3032 // a serious error if it tried to handle an exception (such as a null check
3033 // or breakpoint) that the VM was generating for its own correct operation.
3034 //
3035 // This routine may recognize any of the following kinds of signals:
3036 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
3037 // It should be consulted by handlers for any of those signals.
3038 //
3039 // The caller of this routine must pass in the three arguments supplied
3040 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
3041 // field of the structure passed to sigaction(). This routine assumes that
3042 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
3043 //
3044 // Note that the VM will print warnings if it detects conflicting signal
3045 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
3046 //
3047 extern "C" JNIEXPORT int
3048 JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
3049 void* ucontext, int abort_if_unrecognized);
3050
3051 void signalHandler(int sig, siginfo_t* info, void* uc) {
3052 assert(info != NULL && uc != NULL, "it must be old kernel");
3053 int orig_errno = errno; // Preserve errno value over signal handler.
3054 JVM_handle_bsd_signal(sig, info, uc, true);
3055 errno = orig_errno;
3056 }
3057
3058
3059 // This boolean allows users to forward their own non-matching signals
3060 // to JVM_handle_bsd_signal, harmlessly.
3061 bool os::Bsd::signal_handlers_are_installed = false;
3062
3063 // For signal-chaining
3064 struct sigaction os::Bsd::sigact[MAXSIGNUM];
3065 unsigned int os::Bsd::sigs = 0;
3066 bool os::Bsd::libjsig_is_loaded = false;
3067 typedef struct sigaction *(*get_signal_t)(int);
3068 get_signal_t os::Bsd::get_signal_action = NULL;
3069
3070 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
3071 struct sigaction *actp = NULL;
3072
3073 if (libjsig_is_loaded) {
3074 // Retrieve the old signal handler from libjsig
3075 actp = (*get_signal_action)(sig);
3076 }
3077 if (actp == NULL) {
3078 // Retrieve the preinstalled signal handler from jvm
3079 actp = get_preinstalled_handler(sig);
3080 }
3081
3082 return actp;
3083 }
3084
3085 static bool call_chained_handler(struct sigaction *actp, int sig,
3086 siginfo_t *siginfo, void *context) {
3087 // Call the old signal handler
3088 if (actp->sa_handler == SIG_DFL) {
3089 // It's more reasonable to let jvm treat it as an unexpected exception
3090 // instead of taking the default action.
3091 return false;
3092 } else if (actp->sa_handler != SIG_IGN) {
3093 if ((actp->sa_flags & SA_NODEFER) == 0) {
3094 // automaticlly block the signal
3095 sigaddset(&(actp->sa_mask), sig);
3096 }
3097
3098 sa_handler_t hand;
3099 sa_sigaction_t sa;
3100 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
3101 // retrieve the chained handler
3102 if (siginfo_flag_set) {
3103 sa = actp->sa_sigaction;
3104 } else {
3105 hand = actp->sa_handler;
3106 }
3107
3108 if ((actp->sa_flags & SA_RESETHAND) != 0) {
3109 actp->sa_handler = SIG_DFL;
3110 }
3111
3112 // try to honor the signal mask
3113 sigset_t oset;
3114 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
3115
3116 // call into the chained handler
3117 if (siginfo_flag_set) {
3118 (*sa)(sig, siginfo, context);
3119 } else {
3120 (*hand)(sig);
3121 }
3122
3123 // restore the signal mask
3124 pthread_sigmask(SIG_SETMASK, &oset, 0);
3125 }
3126 // Tell jvm's signal handler the signal is taken care of.
3127 return true;
3128 }
3129
3130 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
3131 bool chained = false;
3132 // signal-chaining
3133 if (UseSignalChaining) {
3134 struct sigaction *actp = get_chained_signal_action(sig);
3135 if (actp != NULL) {
3136 chained = call_chained_handler(actp, sig, siginfo, context);
3137 }
3138 }
3139 return chained;
3140 }
3141
3142 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) {
3143 if ((( (unsigned int)1 << sig ) & sigs) != 0) {
3144 return &sigact[sig];
3145 }
3146 return NULL;
3147 }
3148
3149 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
3150 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3151 sigact[sig] = oldAct;
3152 sigs |= (unsigned int)1 << sig;
3153 }
3154
3155 // for diagnostic
3156 int os::Bsd::sigflags[MAXSIGNUM];
3157
3158 int os::Bsd::get_our_sigflags(int sig) {
3159 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3160 return sigflags[sig];
3161 }
3162
3163 void os::Bsd::set_our_sigflags(int sig, int flags) {
3164 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3165 sigflags[sig] = flags;
3166 }
3167
3168 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
3169 // Check for overwrite.
3170 struct sigaction oldAct;
3171 sigaction(sig, (struct sigaction*)NULL, &oldAct);
3172
3173 void* oldhand = oldAct.sa_sigaction
3174 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3175 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3176 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
3177 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
3178 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
3179 if (AllowUserSignalHandlers || !set_installed) {
3180 // Do not overwrite; user takes responsibility to forward to us.
3181 return;
3182 } else if (UseSignalChaining) {
3183 // save the old handler in jvm
3184 save_preinstalled_handler(sig, oldAct);
3185 // libjsig also interposes the sigaction() call below and saves the
3186 // old sigaction on it own.
3187 } else {
3188 fatal(err_msg("Encountered unexpected pre-existing sigaction handler "
3189 "%#lx for signal %d.", (long)oldhand, sig));
3190 }
3191 }
3192
3193 struct sigaction sigAct;
3194 sigfillset(&(sigAct.sa_mask));
3195 sigAct.sa_handler = SIG_DFL;
3196 if (!set_installed) {
3197 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3198 } else {
3199 sigAct.sa_sigaction = signalHandler;
3200 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3201 }
3202 #if __APPLE__
3203 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV
3204 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages"
3205 // if the signal handler declares it will handle it on alternate stack.
3206 // Notice we only declare we will handle it on alt stack, but we are not
3207 // actually going to use real alt stack - this is just a workaround.
3208 // Please see ux_exception.c, method catch_mach_exception_raise for details
3209 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c
3210 if (sig == SIGSEGV) {
3211 sigAct.sa_flags |= SA_ONSTACK;
3212 }
3213 #endif
3214
3215 // Save flags, which are set by ours
3216 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3217 sigflags[sig] = sigAct.sa_flags;
3218
3219 int ret = sigaction(sig, &sigAct, &oldAct);
3220 assert(ret == 0, "check");
3221
3222 void* oldhand2 = oldAct.sa_sigaction
3223 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3224 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3225 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
3226 }
3227
3228 // install signal handlers for signals that HotSpot needs to
3229 // handle in order to support Java-level exception handling.
3230
3231 void os::Bsd::install_signal_handlers() {
3232 if (!signal_handlers_are_installed) {
3233 signal_handlers_are_installed = true;
3234
3235 // signal-chaining
3236 typedef void (*signal_setting_t)();
3237 signal_setting_t begin_signal_setting = NULL;
3238 signal_setting_t end_signal_setting = NULL;
3239 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3240 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
3241 if (begin_signal_setting != NULL) {
3242 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3243 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
3244 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
3245 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
3246 libjsig_is_loaded = true;
3247 assert(UseSignalChaining, "should enable signal-chaining");
3248 }
3249 if (libjsig_is_loaded) {
3250 // Tell libjsig jvm is setting signal handlers
3251 (*begin_signal_setting)();
3252 }
3253
3254 set_signal_handler(SIGSEGV, true);
3255 set_signal_handler(SIGPIPE, true);
3256 set_signal_handler(SIGBUS, true);
3257 set_signal_handler(SIGILL, true);
3258 set_signal_handler(SIGFPE, true);
3259 set_signal_handler(SIGXFSZ, true);
3260
3261 #if defined(__APPLE__)
3262 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
3263 // signals caught and handled by the JVM. To work around this, we reset the mach task
3264 // signal handler that's placed on our process by CrashReporter. This disables
3265 // CrashReporter-based reporting.
3266 //
3267 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
3268 // on caught fatal signals.
3269 //
3270 // Additionally, gdb installs both standard BSD signal handlers, and mach exception
3271 // handlers. By replacing the existing task exception handler, we disable gdb's mach
3272 // exception handling, while leaving the standard BSD signal handlers functional.
3273 kern_return_t kr;
3274 kr = task_set_exception_ports(mach_task_self(),
3275 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
3276 MACH_PORT_NULL,
3277 EXCEPTION_STATE_IDENTITY,
3278 MACHINE_THREAD_STATE);
3279
3280 assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
3281 #endif
3282
3283 if (libjsig_is_loaded) {
3284 // Tell libjsig jvm finishes setting signal handlers
3285 (*end_signal_setting)();
3286 }
3287
3288 // We don't activate signal checker if libjsig is in place, we trust ourselves
3289 // and if UserSignalHandler is installed all bets are off
3290 if (CheckJNICalls) {
3291 if (libjsig_is_loaded) {
3292 if (PrintJNIResolving) {
3293 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
3294 }
3295 check_signals = false;
3296 }
3297 if (AllowUserSignalHandlers) {
3298 if (PrintJNIResolving) {
3299 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
3300 }
3301 check_signals = false;
3302 }
3303 }
3304 }
3305 }
3306
3307
3308 /////
3309 // glibc on Bsd platform uses non-documented flag
3310 // to indicate, that some special sort of signal
3311 // trampoline is used.
3312 // We will never set this flag, and we should
3313 // ignore this flag in our diagnostic
3314 #ifdef SIGNIFICANT_SIGNAL_MASK
3315 #undef SIGNIFICANT_SIGNAL_MASK
3316 #endif
3317 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
3318
3319 static const char* get_signal_handler_name(address handler,
3320 char* buf, int buflen) {
3321 int offset;
3322 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
3323 if (found) {
3324 // skip directory names
3325 const char *p1, *p2;
3326 p1 = buf;
3327 size_t len = strlen(os::file_separator());
3328 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
3329 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
3330 } else {
3331 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
3332 }
3333 return buf;
3334 }
3335
3336 static void print_signal_handler(outputStream* st, int sig,
3337 char* buf, size_t buflen) {
3338 struct sigaction sa;
3339
3340 sigaction(sig, NULL, &sa);
3341
3342 // See comment for SIGNIFICANT_SIGNAL_MASK define
3343 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3344
3345 st->print("%s: ", os::exception_name(sig, buf, buflen));
3346
3347 address handler = (sa.sa_flags & SA_SIGINFO)
3348 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
3349 : CAST_FROM_FN_PTR(address, sa.sa_handler);
3350
3351 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
3352 st->print("SIG_DFL");
3353 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
3354 st->print("SIG_IGN");
3355 } else {
3356 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
3357 }
3358
3359 st->print(", sa_mask[0]=" PTR32_FORMAT, *(uint32_t*)&sa.sa_mask);
3360
3361 address rh = VMError::get_resetted_sighandler(sig);
3362 // May be, handler was resetted by VMError?
3363 if(rh != NULL) {
3364 handler = rh;
3365 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
3366 }
3367
3368 st->print(", sa_flags=" PTR32_FORMAT, sa.sa_flags);
3369
3370 // Check: is it our handler?
3371 if(handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
3372 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
3373 // It is our signal handler
3374 // check for flags, reset system-used one!
3375 if((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3376 st->print(
3377 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
3378 os::Bsd::get_our_sigflags(sig));
3379 }
3380 }
3381 st->cr();
3382 }
3383
3384
3385 #define DO_SIGNAL_CHECK(sig) \
3386 if (!sigismember(&check_signal_done, sig)) \
3387 os::Bsd::check_signal_handler(sig)
3388
3389 // This method is a periodic task to check for misbehaving JNI applications
3390 // under CheckJNI, we can add any periodic checks here
3391
3392 void os::run_periodic_checks() {
3393
3394 if (check_signals == false) return;
3395
3396 // SEGV and BUS if overridden could potentially prevent
3397 // generation of hs*.log in the event of a crash, debugging
3398 // such a case can be very challenging, so we absolutely
3399 // check the following for a good measure:
3400 DO_SIGNAL_CHECK(SIGSEGV);
3401 DO_SIGNAL_CHECK(SIGILL);
3402 DO_SIGNAL_CHECK(SIGFPE);
3403 DO_SIGNAL_CHECK(SIGBUS);
3404 DO_SIGNAL_CHECK(SIGPIPE);
3405 DO_SIGNAL_CHECK(SIGXFSZ);
3406
3407
3408 // ReduceSignalUsage allows the user to override these handlers
3409 // see comments at the very top and jvm_solaris.h
3410 if (!ReduceSignalUsage) {
3411 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
3412 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
3413 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
3414 DO_SIGNAL_CHECK(BREAK_SIGNAL);
3415 }
3416
3417 DO_SIGNAL_CHECK(SR_signum);
3418 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL);
3419 }
3420
3421 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
3422
3423 static os_sigaction_t os_sigaction = NULL;
3424
3425 void os::Bsd::check_signal_handler(int sig) {
3426 char buf[O_BUFLEN];
3427 address jvmHandler = NULL;
3428
3429
3430 struct sigaction act;
3431 if (os_sigaction == NULL) {
3432 // only trust the default sigaction, in case it has been interposed
3433 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
3434 if (os_sigaction == NULL) return;
3435 }
3436
3437 os_sigaction(sig, (struct sigaction*)NULL, &act);
3438
3439
3440 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3441
3442 address thisHandler = (act.sa_flags & SA_SIGINFO)
3443 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3444 : CAST_FROM_FN_PTR(address, act.sa_handler) ;
3445
3446
3447 switch(sig) {
3448 case SIGSEGV:
3449 case SIGBUS:
3450 case SIGFPE:
3451 case SIGPIPE:
3452 case SIGILL:
3453 case SIGXFSZ:
3454 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
3455 break;
3456
3457 case SHUTDOWN1_SIGNAL:
3458 case SHUTDOWN2_SIGNAL:
3459 case SHUTDOWN3_SIGNAL:
3460 case BREAK_SIGNAL:
3461 jvmHandler = (address)user_handler();
3462 break;
3463
3464 case INTERRUPT_SIGNAL:
3465 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL);
3466 break;
3467
3468 default:
3469 if (sig == SR_signum) {
3470 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3471 } else {
3472 return;
3473 }
3474 break;
3475 }
3476
3477 if (thisHandler != jvmHandler) {
3478 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3479 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3480 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3481 // No need to check this sig any longer
3482 sigaddset(&check_signal_done, sig);
3483 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3484 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3485 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig));
3486 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags);
3487 // No need to check this sig any longer
3488 sigaddset(&check_signal_done, sig);
3489 }
3490
3491 // Dump all the signal
3492 if (sigismember(&check_signal_done, sig)) {
3493 print_signal_handlers(tty, buf, O_BUFLEN);
3494 }
3495 }
3496
3497 extern void report_error(char* file_name, int line_no, char* title, char* format, ...);
3498
3499 extern bool signal_name(int signo, char* buf, size_t len);
3500
3501 const char* os::exception_name(int exception_code, char* buf, size_t size) {
3502 if (0 < exception_code && exception_code <= SIGRTMAX) {
3503 // signal
3504 if (!signal_name(exception_code, buf, size)) {
3505 jio_snprintf(buf, size, "SIG%d", exception_code);
3506 }
3507 return buf;
3508 } else {
3509 return NULL;
3510 }
3511 }
3512
3513 // this is called _before_ the most of global arguments have been parsed
3514 void os::init(void) {
3515 char dummy; /* used to get a guess on initial stack address */
3516 // first_hrtime = gethrtime();
3517
3518 // With BsdThreads the JavaMain thread pid (primordial thread)
3519 // is different than the pid of the java launcher thread.
3520 // So, on Bsd, the launcher thread pid is passed to the VM
3521 // via the sun.java.launcher.pid property.
3522 // Use this property instead of getpid() if it was correctly passed.
3523 // See bug 6351349.
3524 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid();
3525
3526 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid();
3527
3528 clock_tics_per_sec = CLK_TCK;
3529
3530 init_random(1234567);
3531
3532 ThreadCritical::initialize();
3533
3534 Bsd::set_page_size(getpagesize());
3535 if (Bsd::page_size() == -1) {
3536 fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)",
3537 strerror(errno)));
3538 }
3539 init_page_sizes((size_t) Bsd::page_size());
3540
3541 Bsd::initialize_system_info();
3542
3543 // main_thread points to the aboriginal thread
3544 Bsd::_main_thread = pthread_self();
3545
3546 Bsd::clock_init();
3547 initial_time_count = os::elapsed_counter();
3548
3549 #ifdef __APPLE__
3550 // XXXDARWIN
3551 // Work around the unaligned VM callbacks in hotspot's
3552 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on
3553 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces
3554 // alignment when doing symbol lookup. To work around this, we force early
3555 // binding of all symbols now, thus binding when alignment is known-good.
3556 _dyld_bind_fully_image_containing_address((const void *) &os::init);
3557 #endif
3558 }
3559
3560 // To install functions for atexit system call
3561 extern "C" {
3562 static void perfMemory_exit_helper() {
3563 perfMemory_exit();
3564 }
3565 }
3566
3567 // this is called _after_ the global arguments have been parsed
3568 jint os::init_2(void)
3569 {
3570 // Allocate a single page and mark it as readable for safepoint polling
3571 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3572 guarantee( polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page" );
3573
3574 os::set_polling_page( polling_page );
3575
3576 #ifndef PRODUCT
3577 if(Verbose && PrintMiscellaneous)
3578 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page);
3579 #endif
3580
3581 if (!UseMembar) {
3582 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3583 guarantee( mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page");
3584 os::set_memory_serialize_page( mem_serialize_page );
3585
3586 #ifndef PRODUCT
3587 if(Verbose && PrintMiscellaneous)
3588 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page);
3589 #endif
3590 }
3591
3592 os::large_page_init();
3593
3594 // initialize suspend/resume support - must do this before signal_sets_init()
3595 if (SR_initialize() != 0) {
3596 perror("SR_initialize failed");
3597 return JNI_ERR;
3598 }
3599
3600 Bsd::signal_sets_init();
3601 Bsd::install_signal_handlers();
3602
3603 // Check minimum allowable stack size for thread creation and to initialize
3604 // the java system classes, including StackOverflowError - depends on page
3605 // size. Add a page for compiler2 recursion in main thread.
3606 // Add in 2*BytesPerWord times page size to account for VM stack during
3607 // class initialization depending on 32 or 64 bit VM.
3608 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed,
3609 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+
3610 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size());
3611
3612 size_t threadStackSizeInBytes = ThreadStackSize * K;
3613 if (threadStackSizeInBytes != 0 &&
3614 threadStackSizeInBytes < os::Bsd::min_stack_allowed) {
3615 tty->print_cr("\nThe stack size specified is too small, "
3616 "Specify at least %dk",
3617 os::Bsd::min_stack_allowed/ K);
3618 return JNI_ERR;
3619 }
3620
3621 // Make the stack size a multiple of the page size so that
3622 // the yellow/red zones can be guarded.
3623 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes,
3624 vm_page_size()));
3625
3626 if (MaxFDLimit) {
3627 // set the number of file descriptors to max. print out error
3628 // if getrlimit/setrlimit fails but continue regardless.
3629 struct rlimit nbr_files;
3630 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3631 if (status != 0) {
3632 if (PrintMiscellaneous && (Verbose || WizardMode))
3633 perror("os::init_2 getrlimit failed");
3634 } else {
3635 nbr_files.rlim_cur = nbr_files.rlim_max;
3636
3637 #ifdef __APPLE__
3638 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3639 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3640 // be used instead
3641 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3642 #endif
3643
3644 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3645 if (status != 0) {
3646 if (PrintMiscellaneous && (Verbose || WizardMode))
3647 perror("os::init_2 setrlimit failed");
3648 }
3649 }
3650 }
3651
3652 // at-exit methods are called in the reverse order of their registration.
3653 // atexit functions are called on return from main or as a result of a
3654 // call to exit(3C). There can be only 32 of these functions registered
3655 // and atexit() does not set errno.
3656
3657 if (PerfAllowAtExitRegistration) {
3658 // only register atexit functions if PerfAllowAtExitRegistration is set.
3659 // atexit functions can be delayed until process exit time, which
3660 // can be problematic for embedded VM situations. Embedded VMs should
3661 // call DestroyJavaVM() to assure that VM resources are released.
3662
3663 // note: perfMemory_exit_helper atexit function may be removed in
3664 // the future if the appropriate cleanup code can be added to the
3665 // VM_Exit VMOperation's doit method.
3666 if (atexit(perfMemory_exit_helper) != 0) {
3667 warning("os::init2 atexit(perfMemory_exit_helper) failed");
3668 }
3669 }
3670
3671 // initialize thread priority policy
3672 prio_init();
3673
3674 #ifdef __APPLE__
3675 // dynamically link to objective c gc registration
3676 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3677 if (handleLibObjc != NULL) {
3678 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3679 }
3680 #endif
3681
3682 return JNI_OK;
3683 }
3684
3685 // this is called at the end of vm_initialization
3686 void os::init_3(void) { }
3687
3688 // Mark the polling page as unreadable
3689 void os::make_polling_page_unreadable(void) {
3690 if( !guard_memory((char*)_polling_page, Bsd::page_size()) )
3691 fatal("Could not disable polling page");
3692 };
3693
3694 // Mark the polling page as readable
3695 void os::make_polling_page_readable(void) {
3696 if( !bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
3697 fatal("Could not enable polling page");
3698 }
3699 };
3700
3701 int os::active_processor_count() {
3702 return _processor_count;
3703 }
3704
3705 void os::set_native_thread_name(const char *name) {
3706 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3707 // This is only supported in Snow Leopard and beyond
3708 if (name != NULL) {
3709 // Add a "Java: " prefix to the name
3710 char buf[MAXTHREADNAMESIZE];
3711 snprintf(buf, sizeof(buf), "Java: %s", name);
3712 pthread_setname_np(buf);
3713 }
3714 #endif
3715 }
3716
3717 bool os::distribute_processes(uint length, uint* distribution) {
3718 // Not yet implemented.
3719 return false;
3720 }
3721
3722 bool os::bind_to_processor(uint processor_id) {
3723 // Not yet implemented.
3724 return false;
3725 }
3726
3727 void os::SuspendedThreadTask::internal_do_task() {
3728 if (do_suspend(_thread->osthread())) {
3729 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
3730 do_task(context);
3731 do_resume(_thread->osthread());
3732 }
3733 }
3734
3735 ///
3736 class PcFetcher : public os::SuspendedThreadTask {
3737 public:
3738 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {}
3739 ExtendedPC result();
3740 protected:
3741 void do_task(const os::SuspendedThreadTaskContext& context);
3742 private:
3743 ExtendedPC _epc;
3744 };
3745
3746 ExtendedPC PcFetcher::result() {
3747 guarantee(is_done(), "task is not done yet.");
3748 return _epc;
3749 }
3750
3751 void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) {
3752 Thread* thread = context.thread();
3753 OSThread* osthread = thread->osthread();
3754 if (osthread->ucontext() != NULL) {
3755 _epc = os::Bsd::ucontext_get_pc((ucontext_t *) context.ucontext());
3756 } else {
3757 // NULL context is unexpected, double-check this is the VMThread
3758 guarantee(thread->is_VM_thread(), "can only be called for VMThread");
3759 }
3760 }
3761
3762 // Suspends the target using the signal mechanism and then grabs the PC before
3763 // resuming the target. Used by the flat-profiler only
3764 ExtendedPC os::get_thread_pc(Thread* thread) {
3765 // Make sure that it is called by the watcher for the VMThread
3766 assert(Thread::current()->is_Watcher_thread(), "Must be watcher");
3767 assert(thread->is_VM_thread(), "Can only be called for VMThread");
3768
3769 PcFetcher fetcher(thread);
3770 fetcher.run();
3771 return fetcher.result();
3772 }
3773
3774 int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime)
3775 {
3776 return pthread_cond_timedwait(_cond, _mutex, _abstime);
3777 }
3778
3779 ////////////////////////////////////////////////////////////////////////////////
3780 // debug support
3781
3782 bool os::find(address addr, outputStream* st) {
3783 Dl_info dlinfo;
3784 memset(&dlinfo, 0, sizeof(dlinfo));
3785 if (dladdr(addr, &dlinfo) != 0) {
3786 st->print(PTR_FORMAT ": ", addr);
3787 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) {
3788 st->print("%s+%#x", dlinfo.dli_sname,
3789 addr - (intptr_t)dlinfo.dli_saddr);
3790 } else if (dlinfo.dli_fbase != NULL) {
3791 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase);
3792 } else {
3793 st->print("<absolute address>");
3794 }
3795 if (dlinfo.dli_fname != NULL) {
3796 st->print(" in %s", dlinfo.dli_fname);
3797 }
3798 if (dlinfo.dli_fbase != NULL) {
3799 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase);
3800 }
3801 st->cr();
3802
3803 if (Verbose) {
3804 // decode some bytes around the PC
3805 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
3806 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size());
3807 address lowest = (address) dlinfo.dli_sname;
3808 if (!lowest) lowest = (address) dlinfo.dli_fbase;
3809 if (begin < lowest) begin = lowest;
3810 Dl_info dlinfo2;
3811 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr
3812 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin)
3813 end = (address) dlinfo2.dli_saddr;
3814 Disassembler::decode(begin, end, st);
3815 }
3816 return true;
3817 }
3818 return false;
3819 }
3820
3821 ////////////////////////////////////////////////////////////////////////////////
3822 // misc
3823
3824 // This does not do anything on Bsd. This is basically a hook for being
3825 // able to use structured exception handling (thread-local exception filters)
3826 // on, e.g., Win32.
3827 void
3828 os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method,
3829 JavaCallArguments* args, Thread* thread) {
3830 f(value, method, args, thread);
3831 }
3832
3833 void os::print_statistics() {
3834 }
3835
3836 int os::message_box(const char* title, const char* message) {
3837 int i;
3838 fdStream err(defaultStream::error_fd());
3839 for (i = 0; i < 78; i++) err.print_raw("=");
3840 err.cr();
3841 err.print_raw_cr(title);
3842 for (i = 0; i < 78; i++) err.print_raw("-");
3843 err.cr();
3844 err.print_raw_cr(message);
3845 for (i = 0; i < 78; i++) err.print_raw("=");
3846 err.cr();
3847
3848 char buf[16];
3849 // Prevent process from exiting upon "read error" without consuming all CPU
3850 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3851
3852 return buf[0] == 'y' || buf[0] == 'Y';
3853 }
3854
3855 int os::stat(const char *path, struct stat *sbuf) {
3856 char pathbuf[MAX_PATH];
3857 if (strlen(path) > MAX_PATH - 1) {
3858 errno = ENAMETOOLONG;
3859 return -1;
3860 }
3861 os::native_path(strcpy(pathbuf, path));
3862 return ::stat(pathbuf, sbuf);
3863 }
3864
3865 bool os::check_heap(bool force) {
3866 return true;
3867 }
3868
3869 int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) {
3870 return ::vsnprintf(buf, count, format, args);
3871 }
3872
3873 // Is a (classpath) directory empty?
3874 bool os::dir_is_empty(const char* path) {
3875 DIR *dir = NULL;
3876 struct dirent *ptr;
3877
3878 dir = opendir(path);
3879 if (dir == NULL) return true;
3880
3881 /* Scan the directory */
3882 bool result = true;
3883 char buf[sizeof(struct dirent) + MAX_PATH];
3884 while (result && (ptr = ::readdir(dir)) != NULL) {
3885 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3886 result = false;
3887 }
3888 }
3889 closedir(dir);
3890 return result;
3891 }
3892
3893 // This code originates from JDK's sysOpen and open64_w
3894 // from src/solaris/hpi/src/system_md.c
3895
3896 #ifndef O_DELETE
3897 #define O_DELETE 0x10000
3898 #endif
3899
3900 // Open a file. Unlink the file immediately after open returns
3901 // if the specified oflag has the O_DELETE flag set.
3902 // O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c
3903
3904 int os::open(const char *path, int oflag, int mode) {
3905
3906 if (strlen(path) > MAX_PATH - 1) {
3907 errno = ENAMETOOLONG;
3908 return -1;
3909 }
3910 int fd;
3911 int o_delete = (oflag & O_DELETE);
3912 oflag = oflag & ~O_DELETE;
3913
3914 fd = ::open(path, oflag, mode);
3915 if (fd == -1) return -1;
3916
3917 //If the open succeeded, the file might still be a directory
3918 {
3919 struct stat buf;
3920 int ret = ::fstat(fd, &buf);
3921 int st_mode = buf.st_mode;
3922
3923 if (ret != -1) {
3924 if ((st_mode & S_IFMT) == S_IFDIR) {
3925 errno = EISDIR;
3926 ::close(fd);
3927 return -1;
3928 }
3929 } else {
3930 ::close(fd);
3931 return -1;
3932 }
3933 }
3934
3935 /*
3936 * All file descriptors that are opened in the JVM and not
3937 * specifically destined for a subprocess should have the
3938 * close-on-exec flag set. If we don't set it, then careless 3rd
3939 * party native code might fork and exec without closing all
3940 * appropriate file descriptors (e.g. as we do in closeDescriptors in
3941 * UNIXProcess.c), and this in turn might:
3942 *
3943 * - cause end-of-file to fail to be detected on some file
3944 * descriptors, resulting in mysterious hangs, or
3945 *
3946 * - might cause an fopen in the subprocess to fail on a system
3947 * suffering from bug 1085341.
3948 *
3949 * (Yes, the default setting of the close-on-exec flag is a Unix
3950 * design flaw)
3951 *
3952 * See:
3953 * 1085341: 32-bit stdio routines should support file descriptors >255
3954 * 4843136: (process) pipe file descriptor from Runtime.exec not being closed
3955 * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
3956 */
3957 #ifdef FD_CLOEXEC
3958 {
3959 int flags = ::fcntl(fd, F_GETFD);
3960 if (flags != -1)
3961 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
3962 }
3963 #endif
3964
3965 if (o_delete != 0) {
3966 ::unlink(path);
3967 }
3968 return fd;
3969 }
3970
3971
3972 // create binary file, rewriting existing file if required
3973 int os::create_binary_file(const char* path, bool rewrite_existing) {
3974 int oflags = O_WRONLY | O_CREAT;
3975 if (!rewrite_existing) {
3976 oflags |= O_EXCL;
3977 }
3978 return ::open(path, oflags, S_IREAD | S_IWRITE);
3979 }
3980
3981 // return current position of file pointer
3982 jlong os::current_file_offset(int fd) {
3983 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
3984 }
3985
3986 // move file pointer to the specified offset
3987 jlong os::seek_to_file_offset(int fd, jlong offset) {
3988 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
3989 }
3990
3991 // This code originates from JDK's sysAvailable
3992 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
3993
3994 int os::available(int fd, jlong *bytes) {
3995 jlong cur, end;
3996 int mode;
3997 struct stat buf;
3998
3999 if (::fstat(fd, &buf) >= 0) {
4000 mode = buf.st_mode;
4001 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
4002 /*
4003 * XXX: is the following call interruptible? If so, this might
4004 * need to go through the INTERRUPT_IO() wrapper as for other
4005 * blocking, interruptible calls in this file.
4006 */
4007 int n;
4008 if (::ioctl(fd, FIONREAD, &n) >= 0) {
4009 *bytes = n;
4010 return 1;
4011 }
4012 }
4013 }
4014 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
4015 return 0;
4016 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
4017 return 0;
4018 } else if (::lseek(fd, cur, SEEK_SET) == -1) {
4019 return 0;
4020 }
4021 *bytes = end - cur;
4022 return 1;
4023 }
4024
4025 int os::socket_available(int fd, jint *pbytes) {
4026 if (fd < 0)
4027 return OS_OK;
4028
4029 int ret;
4030
4031 RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret);
4032
4033 //%% note ioctl can return 0 when successful, JVM_SocketAvailable
4034 // is expected to return 0 on failure and 1 on success to the jdk.
4035
4036 return (ret == OS_ERR) ? 0 : 1;
4037 }
4038
4039 // Map a block of memory.
4040 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
4041 char *addr, size_t bytes, bool read_only,
4042 bool allow_exec) {
4043 int prot;
4044 int flags;
4045
4046 if (read_only) {
4047 prot = PROT_READ;
4048 flags = MAP_SHARED;
4049 } else {
4050 prot = PROT_READ | PROT_WRITE;
4051 flags = MAP_PRIVATE;
4052 }
4053
4054 if (allow_exec) {
4055 prot |= PROT_EXEC;
4056 }
4057
4058 if (addr != NULL) {
4059 flags |= MAP_FIXED;
4060 }
4061
4062 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
4063 fd, file_offset);
4064 if (mapped_address == MAP_FAILED) {
4065 return NULL;
4066 }
4067 return mapped_address;
4068 }
4069
4070
4071 // Remap a block of memory.
4072 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
4073 char *addr, size_t bytes, bool read_only,
4074 bool allow_exec) {
4075 // same as map_memory() on this OS
4076 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
4077 allow_exec);
4078 }
4079
4080
4081 // Unmap a block of memory.
4082 bool os::pd_unmap_memory(char* addr, size_t bytes) {
4083 return munmap(addr, bytes) == 0;
4084 }
4085
4086 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
4087 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
4088 // of a thread.
4089 //
4090 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
4091 // the fast estimate available on the platform.
4092
4093 jlong os::current_thread_cpu_time() {
4094 #ifdef __APPLE__
4095 return os::thread_cpu_time(Thread::current(), true /* user + sys */);
4096 #else
4097 Unimplemented();
4098 return 0;
4099 #endif
4100 }
4101
4102 jlong os::thread_cpu_time(Thread* thread) {
4103 #ifdef __APPLE__
4104 return os::thread_cpu_time(thread, true /* user + sys */);
4105 #else
4106 Unimplemented();
4107 return 0;
4108 #endif
4109 }
4110
4111 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
4112 #ifdef __APPLE__
4113 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
4114 #else
4115 Unimplemented();
4116 return 0;
4117 #endif
4118 }
4119
4120 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
4121 #ifdef __APPLE__
4122 struct thread_basic_info tinfo;
4123 mach_msg_type_number_t tcount = THREAD_INFO_MAX;
4124 kern_return_t kr;
4125 thread_t mach_thread;
4126
4127 mach_thread = thread->osthread()->thread_id();
4128 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
4129 if (kr != KERN_SUCCESS)
4130 return -1;
4131
4132 if (user_sys_cpu_time) {
4133 jlong nanos;
4134 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
4135 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
4136 return nanos;
4137 } else {
4138 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
4139 }
4140 #else
4141 Unimplemented();
4142 return 0;
4143 #endif
4144 }
4145
4146
4147 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4148 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4149 info_ptr->may_skip_backward = false; // elapsed time not wall time
4150 info_ptr->may_skip_forward = false; // elapsed time not wall time
4151 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4152 }
4153
4154 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4155 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4156 info_ptr->may_skip_backward = false; // elapsed time not wall time
4157 info_ptr->may_skip_forward = false; // elapsed time not wall time
4158 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4159 }
4160
4161 bool os::is_thread_cpu_time_supported() {
4162 #ifdef __APPLE__
4163 return true;
4164 #else
4165 return false;
4166 #endif
4167 }
4168
4169 // System loadavg support. Returns -1 if load average cannot be obtained.
4170 // Bsd doesn't yet have a (official) notion of processor sets,
4171 // so just return the system wide load average.
4172 int os::loadavg(double loadavg[], int nelem) {
4173 return ::getloadavg(loadavg, nelem);
4174 }
4175
4176 void os::pause() {
4177 char filename[MAX_PATH];
4178 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
4179 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
4180 } else {
4181 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
4182 }
4183
4184 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
4185 if (fd != -1) {
4186 struct stat buf;
4187 ::close(fd);
4188 while (::stat(filename, &buf) == 0) {
4189 (void)::poll(NULL, 0, 100);
4190 }
4191 } else {
4192 jio_fprintf(stderr,
4193 "Could not open pause file '%s', continuing immediately.\n", filename);
4194 }
4195 }
4196
4197
4198 // Refer to the comments in os_solaris.cpp park-unpark.
4199 //
4200 // Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can
4201 // hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable.
4202 // For specifics regarding the bug see GLIBC BUGID 261237 :
4203 // http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html.
4204 // Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future
4205 // will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar
4206 // is used. (The simple C test-case provided in the GLIBC bug report manifests the
4207 // hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos()
4208 // and monitorenter when we're using 1-0 locking. All those operations may result in
4209 // calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version
4210 // of libpthread avoids the problem, but isn't practical.
4211 //
4212 // Possible remedies:
4213 //
4214 // 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work.
4215 // This is palliative and probabilistic, however. If the thread is preempted
4216 // between the call to compute_abstime() and pthread_cond_timedwait(), more
4217 // than the minimum period may have passed, and the abstime may be stale (in the
4218 // past) resultin in a hang. Using this technique reduces the odds of a hang
4219 // but the JVM is still vulnerable, particularly on heavily loaded systems.
4220 //
4221 // 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead
4222 // of the usual flag-condvar-mutex idiom. The write side of the pipe is set
4223 // NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo)
4224 // reduces to poll()+read(). This works well, but consumes 2 FDs per extant
4225 // thread.
4226 //
4227 // 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread
4228 // that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing
4229 // a timeout request to the chron thread and then blocking via pthread_cond_wait().
4230 // This also works well. In fact it avoids kernel-level scalability impediments
4231 // on certain platforms that don't handle lots of active pthread_cond_timedwait()
4232 // timers in a graceful fashion.
4233 //
4234 // 4. When the abstime value is in the past it appears that control returns
4235 // correctly from pthread_cond_timedwait(), but the condvar is left corrupt.
4236 // Subsequent timedwait/wait calls may hang indefinitely. Given that, we
4237 // can avoid the problem by reinitializing the condvar -- by cond_destroy()
4238 // followed by cond_init() -- after all calls to pthread_cond_timedwait().
4239 // It may be possible to avoid reinitialization by checking the return
4240 // value from pthread_cond_timedwait(). In addition to reinitializing the
4241 // condvar we must establish the invariant that cond_signal() is only called
4242 // within critical sections protected by the adjunct mutex. This prevents
4243 // cond_signal() from "seeing" a condvar that's in the midst of being
4244 // reinitialized or that is corrupt. Sadly, this invariant obviates the
4245 // desirable signal-after-unlock optimization that avoids futile context switching.
4246 //
4247 // I'm also concerned that some versions of NTPL might allocate an auxilliary
4248 // structure when a condvar is used or initialized. cond_destroy() would
4249 // release the helper structure. Our reinitialize-after-timedwait fix
4250 // put excessive stress on malloc/free and locks protecting the c-heap.
4251 //
4252 // We currently use (4). See the WorkAroundNTPLTimedWaitHang flag.
4253 // It may be possible to refine (4) by checking the kernel and NTPL verisons
4254 // and only enabling the work-around for vulnerable environments.
4255
4256 // utility to compute the abstime argument to timedwait:
4257 // millis is the relative timeout time
4258 // abstime will be the absolute timeout time
4259 // TODO: replace compute_abstime() with unpackTime()
4260
4261 static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) {
4262 if (millis < 0) millis = 0;
4263 struct timeval now;
4264 int status = gettimeofday(&now, NULL);
4265 assert(status == 0, "gettimeofday");
4266 jlong seconds = millis / 1000;
4267 millis %= 1000;
4268 if (seconds > 50000000) { // see man cond_timedwait(3T)
4269 seconds = 50000000;
4270 }
4271 abstime->tv_sec = now.tv_sec + seconds;
4272 long usec = now.tv_usec + millis * 1000;
4273 if (usec >= 1000000) {
4274 abstime->tv_sec += 1;
4275 usec -= 1000000;
4276 }
4277 abstime->tv_nsec = usec * 1000;
4278 return abstime;
4279 }
4280
4281
4282 // Test-and-clear _Event, always leaves _Event set to 0, returns immediately.
4283 // Conceptually TryPark() should be equivalent to park(0).
4284
4285 int os::PlatformEvent::TryPark() {
4286 for (;;) {
4287 const int v = _Event ;
4288 guarantee ((v == 0) || (v == 1), "invariant") ;
4289 if (Atomic::cmpxchg (0, &_Event, v) == v) return v ;
4290 }
4291 }
4292
4293 void os::PlatformEvent::park() { // AKA "down()"
4294 // Invariant: Only the thread associated with the Event/PlatformEvent
4295 // may call park().
4296 // TODO: assert that _Assoc != NULL or _Assoc == Self
4297 int v ;
4298 for (;;) {
4299 v = _Event ;
4300 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4301 }
4302 guarantee (v >= 0, "invariant") ;
4303 if (v == 0) {
4304 // Do this the hard way by blocking ...
4305 int status = pthread_mutex_lock(_mutex);
4306 assert_status(status == 0, status, "mutex_lock");
4307 guarantee (_nParked == 0, "invariant") ;
4308 ++ _nParked ;
4309 while (_Event < 0) {
4310 status = pthread_cond_wait(_cond, _mutex);
4311 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ...
4312 // Treat this the same as if the wait was interrupted
4313 if (status == ETIMEDOUT) { status = EINTR; }
4314 assert_status(status == 0 || status == EINTR, status, "cond_wait");
4315 }
4316 -- _nParked ;
4317
4318 _Event = 0 ;
4319 status = pthread_mutex_unlock(_mutex);
4320 assert_status(status == 0, status, "mutex_unlock");
4321 // Paranoia to ensure our locked and lock-free paths interact
4322 // correctly with each other.
4323 OrderAccess::fence();
4324 }
4325 guarantee (_Event >= 0, "invariant") ;
4326 }
4327
4328 int os::PlatformEvent::park(jlong millis) {
4329 guarantee (_nParked == 0, "invariant") ;
4330
4331 int v ;
4332 for (;;) {
4333 v = _Event ;
4334 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4335 }
4336 guarantee (v >= 0, "invariant") ;
4337 if (v != 0) return OS_OK ;
4338
4339 // We do this the hard way, by blocking the thread.
4340 // Consider enforcing a minimum timeout value.
4341 struct timespec abst;
4342 compute_abstime(&abst, millis);
4343
4344 int ret = OS_TIMEOUT;
4345 int status = pthread_mutex_lock(_mutex);
4346 assert_status(status == 0, status, "mutex_lock");
4347 guarantee (_nParked == 0, "invariant") ;
4348 ++_nParked ;
4349
4350 // Object.wait(timo) will return because of
4351 // (a) notification
4352 // (b) timeout
4353 // (c) thread.interrupt
4354 //
4355 // Thread.interrupt and object.notify{All} both call Event::set.
4356 // That is, we treat thread.interrupt as a special case of notification.
4357 // The underlying Solaris implementation, cond_timedwait, admits
4358 // spurious/premature wakeups, but the JLS/JVM spec prevents the
4359 // JVM from making those visible to Java code. As such, we must
4360 // filter out spurious wakeups. We assume all ETIME returns are valid.
4361 //
4362 // TODO: properly differentiate simultaneous notify+interrupt.
4363 // In that case, we should propagate the notify to another waiter.
4364
4365 while (_Event < 0) {
4366 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst);
4367 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4368 pthread_cond_destroy (_cond);
4369 pthread_cond_init (_cond, NULL) ;
4370 }
4371 assert_status(status == 0 || status == EINTR ||
4372 status == ETIMEDOUT,
4373 status, "cond_timedwait");
4374 if (!FilterSpuriousWakeups) break ; // previous semantics
4375 if (status == ETIMEDOUT) break ;
4376 // We consume and ignore EINTR and spurious wakeups.
4377 }
4378 --_nParked ;
4379 if (_Event >= 0) {
4380 ret = OS_OK;
4381 }
4382 _Event = 0 ;
4383 status = pthread_mutex_unlock(_mutex);
4384 assert_status(status == 0, status, "mutex_unlock");
4385 assert (_nParked == 0, "invariant") ;
4386 // Paranoia to ensure our locked and lock-free paths interact
4387 // correctly with each other.
4388 OrderAccess::fence();
4389 return ret;
4390 }
4391
4392 void os::PlatformEvent::unpark() {
4393 // Transitions for _Event:
4394 // 0 :=> 1
4395 // 1 :=> 1
4396 // -1 :=> either 0 or 1; must signal target thread
4397 // That is, we can safely transition _Event from -1 to either
4398 // 0 or 1. Forcing 1 is slightly more efficient for back-to-back
4399 // unpark() calls.
4400 // See also: "Semaphores in Plan 9" by Mullender & Cox
4401 //
4402 // Note: Forcing a transition from "-1" to "1" on an unpark() means
4403 // that it will take two back-to-back park() calls for the owning
4404 // thread to block. This has the benefit of forcing a spurious return
4405 // from the first park() call after an unpark() call which will help
4406 // shake out uses of park() and unpark() without condition variables.
4407
4408 if (Atomic::xchg(1, &_Event) >= 0) return;
4409
4410 // Wait for the thread associated with the event to vacate
4411 int status = pthread_mutex_lock(_mutex);
4412 assert_status(status == 0, status, "mutex_lock");
4413 int AnyWaiters = _nParked;
4414 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant");
4415 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) {
4416 AnyWaiters = 0;
4417 pthread_cond_signal(_cond);
4418 }
4419 status = pthread_mutex_unlock(_mutex);
4420 assert_status(status == 0, status, "mutex_unlock");
4421 if (AnyWaiters != 0) {
4422 status = pthread_cond_signal(_cond);
4423 assert_status(status == 0, status, "cond_signal");
4424 }
4425
4426 // Note that we signal() _after dropping the lock for "immortal" Events.
4427 // This is safe and avoids a common class of futile wakeups. In rare
4428 // circumstances this can cause a thread to return prematurely from
4429 // cond_{timed}wait() but the spurious wakeup is benign and the victim will
4430 // simply re-test the condition and re-park itself.
4431 }
4432
4433
4434 // JSR166
4435 // -------------------------------------------------------
4436
4437 /*
4438 * The solaris and bsd implementations of park/unpark are fairly
4439 * conservative for now, but can be improved. They currently use a
4440 * mutex/condvar pair, plus a a count.
4441 * Park decrements count if > 0, else does a condvar wait. Unpark
4442 * sets count to 1 and signals condvar. Only one thread ever waits
4443 * on the condvar. Contention seen when trying to park implies that someone
4444 * is unparking you, so don't wait. And spurious returns are fine, so there
4445 * is no need to track notifications.
4446 */
4447
4448 #define MAX_SECS 100000000
4449 /*
4450 * This code is common to bsd and solaris and will be moved to a
4451 * common place in dolphin.
4452 *
4453 * The passed in time value is either a relative time in nanoseconds
4454 * or an absolute time in milliseconds. Either way it has to be unpacked
4455 * into suitable seconds and nanoseconds components and stored in the
4456 * given timespec structure.
4457 * Given time is a 64-bit value and the time_t used in the timespec is only
4458 * a signed-32-bit value (except on 64-bit Bsd) we have to watch for
4459 * overflow if times way in the future are given. Further on Solaris versions
4460 * prior to 10 there is a restriction (see cond_timedwait) that the specified
4461 * number of seconds, in abstime, is less than current_time + 100,000,000.
4462 * As it will be 28 years before "now + 100000000" will overflow we can
4463 * ignore overflow and just impose a hard-limit on seconds using the value
4464 * of "now + 100,000,000". This places a limit on the timeout of about 3.17
4465 * years from "now".
4466 */
4467
4468 static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) {
4469 assert (time > 0, "convertTime");
4470
4471 struct timeval now;
4472 int status = gettimeofday(&now, NULL);
4473 assert(status == 0, "gettimeofday");
4474
4475 time_t max_secs = now.tv_sec + MAX_SECS;
4476
4477 if (isAbsolute) {
4478 jlong secs = time / 1000;
4479 if (secs > max_secs) {
4480 absTime->tv_sec = max_secs;
4481 }
4482 else {
4483 absTime->tv_sec = secs;
4484 }
4485 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC;
4486 }
4487 else {
4488 jlong secs = time / NANOSECS_PER_SEC;
4489 if (secs >= MAX_SECS) {
4490 absTime->tv_sec = max_secs;
4491 absTime->tv_nsec = 0;
4492 }
4493 else {
4494 absTime->tv_sec = now.tv_sec + secs;
4495 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000;
4496 if (absTime->tv_nsec >= NANOSECS_PER_SEC) {
4497 absTime->tv_nsec -= NANOSECS_PER_SEC;
4498 ++absTime->tv_sec; // note: this must be <= max_secs
4499 }
4500 }
4501 }
4502 assert(absTime->tv_sec >= 0, "tv_sec < 0");
4503 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs");
4504 assert(absTime->tv_nsec >= 0, "tv_nsec < 0");
4505 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec");
4506 }
4507
4508 void Parker::park(bool isAbsolute, jlong time) {
4509 // Ideally we'd do something useful while spinning, such
4510 // as calling unpackTime().
4511
4512 // Optional fast-path check:
4513 // Return immediately if a permit is available.
4514 // We depend on Atomic::xchg() having full barrier semantics
4515 // since we are doing a lock-free update to _counter.
4516 if (Atomic::xchg(0, &_counter) > 0) return;
4517
4518 Thread* thread = Thread::current();
4519 assert(thread->is_Java_thread(), "Must be JavaThread");
4520 JavaThread *jt = (JavaThread *)thread;
4521
4522 // Optional optimization -- avoid state transitions if there's an interrupt pending.
4523 // Check interrupt before trying to wait
4524 if (Thread::is_interrupted(thread, false)) {
4525 return;
4526 }
4527
4528 // Next, demultiplex/decode time arguments
4529 struct timespec absTime;
4530 if (time < 0 || (isAbsolute && time == 0) ) { // don't wait at all
4531 return;
4532 }
4533 if (time > 0) {
4534 unpackTime(&absTime, isAbsolute, time);
4535 }
4536
4537
4538 // Enter safepoint region
4539 // Beware of deadlocks such as 6317397.
4540 // The per-thread Parker:: mutex is a classic leaf-lock.
4541 // In particular a thread must never block on the Threads_lock while
4542 // holding the Parker:: mutex. If safepoints are pending both the
4543 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock.
4544 ThreadBlockInVM tbivm(jt);
4545
4546 // Don't wait if cannot get lock since interference arises from
4547 // unblocking. Also. check interrupt before trying wait
4548 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) {
4549 return;
4550 }
4551
4552 int status ;
4553 if (_counter > 0) { // no wait needed
4554 _counter = 0;
4555 status = pthread_mutex_unlock(_mutex);
4556 assert (status == 0, "invariant") ;
4557 // Paranoia to ensure our locked and lock-free paths interact
4558 // correctly with each other and Java-level accesses.
4559 OrderAccess::fence();
4560 return;
4561 }
4562
4563 #ifdef ASSERT
4564 // Don't catch signals while blocked; let the running threads have the signals.
4565 // (This allows a debugger to break into the running thread.)
4566 sigset_t oldsigs;
4567 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals();
4568 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs);
4569 #endif
4570
4571 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
4572 jt->set_suspend_equivalent();
4573 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
4574
4575 if (time == 0) {
4576 status = pthread_cond_wait (_cond, _mutex) ;
4577 } else {
4578 status = os::Bsd::safe_cond_timedwait (_cond, _mutex, &absTime) ;
4579 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4580 pthread_cond_destroy (_cond) ;
4581 pthread_cond_init (_cond, NULL);
4582 }
4583 }
4584 assert_status(status == 0 || status == EINTR ||
4585 status == ETIMEDOUT,
4586 status, "cond_timedwait");
4587
4588 #ifdef ASSERT
4589 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL);
4590 #endif
4591
4592 _counter = 0 ;
4593 status = pthread_mutex_unlock(_mutex) ;
4594 assert_status(status == 0, status, "invariant") ;
4595 // Paranoia to ensure our locked and lock-free paths interact
4596 // correctly with each other and Java-level accesses.
4597 OrderAccess::fence();
4598
4599 // If externally suspended while waiting, re-suspend
4600 if (jt->handle_special_suspend_equivalent_condition()) {
4601 jt->java_suspend_self();
4602 }
4603 }
4604
4605 void Parker::unpark() {
4606 int s, status ;
4607 status = pthread_mutex_lock(_mutex);
4608 assert (status == 0, "invariant") ;
4609 s = _counter;
4610 _counter = 1;
4611 if (s < 1) {
4612 if (WorkAroundNPTLTimedWaitHang) {
4613 status = pthread_cond_signal (_cond) ;
4614 assert (status == 0, "invariant") ;
4615 status = pthread_mutex_unlock(_mutex);
4616 assert (status == 0, "invariant") ;
4617 } else {
4618 status = pthread_mutex_unlock(_mutex);
4619 assert (status == 0, "invariant") ;
4620 status = pthread_cond_signal (_cond) ;
4621 assert (status == 0, "invariant") ;
4622 }
4623 } else {
4624 pthread_mutex_unlock(_mutex);
4625 assert (status == 0, "invariant") ;
4626 }
4627 }
4628
4629
4630 /* Darwin has no "environ" in a dynamic library. */
4631 #ifdef __APPLE__
4632 #include <crt_externs.h>
4633 #define environ (*_NSGetEnviron())
4634 #else
4635 extern char** environ;
4636 #endif
4637
4638 // Run the specified command in a separate process. Return its exit value,
4639 // or -1 on failure (e.g. can't fork a new process).
4640 // Unlike system(), this function can be called from signal handler. It
4641 // doesn't block SIGINT et al.
4642 int os::fork_and_exec(char* cmd) {
4643 const char * argv[4] = {"sh", "-c", cmd, NULL};
4644
4645 // fork() in BsdThreads/NPTL is not async-safe. It needs to run
4646 // pthread_atfork handlers and reset pthread library. All we need is a
4647 // separate process to execve. Make a direct syscall to fork process.
4648 // On IA64 there's no fork syscall, we have to use fork() and hope for
4649 // the best...
4650 pid_t pid = fork();
4651
4652 if (pid < 0) {
4653 // fork failed
4654 return -1;
4655
4656 } else if (pid == 0) {
4657 // child process
4658
4659 // execve() in BsdThreads will call pthread_kill_other_threads_np()
4660 // first to kill every thread on the thread list. Because this list is
4661 // not reset by fork() (see notes above), execve() will instead kill
4662 // every thread in the parent process. We know this is the only thread
4663 // in the new process, so make a system call directly.
4664 // IA64 should use normal execve() from glibc to match the glibc fork()
4665 // above.
4666 execve("/bin/sh", (char* const*)argv, environ);
4667
4668 // execve failed
4669 _exit(-1);
4670
4671 } else {
4672 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
4673 // care about the actual exit code, for now.
4674
4675 int status;
4676
4677 // Wait for the child process to exit. This returns immediately if
4678 // the child has already exited. */
4679 while (waitpid(pid, &status, 0) < 0) {
4680 switch (errno) {
4681 case ECHILD: return 0;
4682 case EINTR: break;
4683 default: return -1;
4684 }
4685 }
4686
4687 if (WIFEXITED(status)) {
4688 // The child exited normally; get its exit code.
4689 return WEXITSTATUS(status);
4690 } else if (WIFSIGNALED(status)) {
4691 // The child exited because of a signal
4692 // The best value to return is 0x80 + signal number,
4693 // because that is what all Unix shells do, and because
4694 // it allows callers to distinguish between process exit and
4695 // process death by signal.
4696 return 0x80 + WTERMSIG(status);
4697 } else {
4698 // Unknown exit code; pass it through
4699 return status;
4700 }
4701 }
4702 }
4703
4704 // is_headless_jre()
4705 //
4706 // Test for the existence of xawt/libmawt.so or libawt_xawt.so
4707 // in order to report if we are running in a headless jre
4708 //
4709 // Since JDK8 xawt/libmawt.so was moved into the same directory
4710 // as libawt.so, and renamed libawt_xawt.so
4711 //
4712 bool os::is_headless_jre() {
4713 struct stat statbuf;
4714 char buf[MAXPATHLEN];
4715 char libmawtpath[MAXPATHLEN];
4716 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX;
4717 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX;
4718 char *p;
4719
4720 // Get path to libjvm.so
4721 os::jvm_path(buf, sizeof(buf));
4722
4723 // Get rid of libjvm.so
4724 p = strrchr(buf, '/');
4725 if (p == NULL) return false;
4726 else *p = '\0';
4727
4728 // Get rid of client or server
4729 p = strrchr(buf, '/');
4730 if (p == NULL) return false;
4731 else *p = '\0';
4732
4733 // check xawt/libmawt.so
4734 strcpy(libmawtpath, buf);
4735 strcat(libmawtpath, xawtstr);
4736 if (::stat(libmawtpath, &statbuf) == 0) return false;
4737
4738 // check libawt_xawt.so
4739 strcpy(libmawtpath, buf);
4740 strcat(libmawtpath, new_xawtstr);
4741 if (::stat(libmawtpath, &statbuf) == 0) return false;
4742
4743 return true;
4744 }
4745
4746 // Get the default path to the core file
4747 // Returns the length of the string
4748 int os::get_core_path(char* buffer, size_t bufferSize) {
4749 int n = jio_snprintf(buffer, bufferSize, "/cores");
4750
4751 // Truncate if theoretical string was longer than bufferSize
4752 n = MIN2(n, (int)bufferSize);
4753
4754 return n;
4755 }
4756
4757 #ifndef PRODUCT
4758 void TestReserveMemorySpecial_test() {
4759 // No tests available for this platform
4760 }
4761 #endif