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 static int SR_finalize();
156
157 julong os::available_memory() {
158 return Bsd::available_memory();
159 }
160
161 julong os::Bsd::available_memory() {
162 // XXXBSD: this is just a stopgap implementation
163 return physical_memory() >> 2;
164 }
165
166 julong os::physical_memory() {
167 return Bsd::physical_memory();
168 }
169
170 julong os::allocatable_physical_memory(julong size) {
171 #ifdef _LP64
172 return size;
173 #else
174 julong result = MIN2(size, (julong)3800*M);
175 if (!is_allocatable(result)) {
176 // See comments under solaris for alignment considerations
177 julong reasonable_size = (julong)2*G - 2 * os::vm_page_size();
178 result = MIN2(size, reasonable_size);
179 }
180 return result;
181 #endif // _LP64
182 }
183
184 ////////////////////////////////////////////////////////////////////////////////
185 // environment support
186
187 bool os::getenv(const char* name, char* buf, int len) {
188 const char* val = ::getenv(name);
189 if (val != NULL && strlen(val) < (size_t)len) {
190 strcpy(buf, val);
191 return true;
192 }
193 if (len > 0) buf[0] = 0; // return a null string
194 return false;
195 }
196
197
198 // Return true if user is running as root.
199
200 bool os::have_special_privileges() {
201 static bool init = false;
202 static bool privileges = false;
203 if (!init) {
204 privileges = (getuid() != geteuid()) || (getgid() != getegid());
205 init = true;
206 }
207 return privileges;
208 }
209
210
211
212 // Cpu architecture string
213 #if defined(ZERO)
214 static char cpu_arch[] = ZERO_LIBARCH;
215 #elif defined(IA64)
216 static char cpu_arch[] = "ia64";
217 #elif defined(IA32)
218 static char cpu_arch[] = "i386";
219 #elif defined(AMD64)
220 static char cpu_arch[] = "amd64";
221 #elif defined(ARM)
222 static char cpu_arch[] = "arm";
223 #elif defined(PPC)
224 static char cpu_arch[] = "ppc";
225 #elif defined(SPARC)
226 # ifdef _LP64
227 static char cpu_arch[] = "sparcv9";
228 # else
229 static char cpu_arch[] = "sparc";
230 # endif
231 #else
232 #error Add appropriate cpu_arch setting
233 #endif
234
235 // Compiler variant
236 #ifdef COMPILER2
237 #define COMPILER_VARIANT "server"
238 #else
239 #define COMPILER_VARIANT "client"
240 #endif
241
242
243 void os::Bsd::initialize_system_info() {
244 int mib[2];
245 size_t len;
246 int cpu_val;
247 julong mem_val;
248
249 /* get processors count via hw.ncpus sysctl */
250 mib[0] = CTL_HW;
251 mib[1] = HW_NCPU;
252 len = sizeof(cpu_val);
253 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) {
254 assert(len == sizeof(cpu_val), "unexpected data size");
255 set_processor_count(cpu_val);
256 }
257 else {
258 set_processor_count(1); // fallback
259 }
260
261 /* get physical memory via hw.memsize sysctl (hw.memsize is used
262 * since it returns a 64 bit value)
263 */
264 mib[0] = CTL_HW;
265 mib[1] = HW_MEMSIZE;
266 len = sizeof(mem_val);
267 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) {
268 assert(len == sizeof(mem_val), "unexpected data size");
269 _physical_memory = mem_val;
270 } else {
271 _physical_memory = 256*1024*1024; // fallback (XXXBSD?)
272 }
273
274 #ifdef __OpenBSD__
275 {
276 // limit _physical_memory memory view on OpenBSD since
277 // datasize rlimit restricts us anyway.
278 struct rlimit limits;
279 getrlimit(RLIMIT_DATA, &limits);
280 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur);
281 }
282 #endif
283 }
284
285 #ifdef __APPLE__
286 static const char *get_home() {
287 const char *home_dir = ::getenv("HOME");
288 if ((home_dir == NULL) || (*home_dir == '\0')) {
289 struct passwd *passwd_info = getpwuid(geteuid());
290 if (passwd_info != NULL) {
291 home_dir = passwd_info->pw_dir;
292 }
293 }
294
295 return home_dir;
296 }
297 #endif
298
299 void os::init_system_properties_values() {
300 // char arch[12];
301 // sysinfo(SI_ARCHITECTURE, arch, sizeof(arch));
302
303 // The next steps are taken in the product version:
304 //
305 // Obtain the JAVA_HOME value from the location of libjvm.so.
306 // This library should be located at:
307 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so.
308 //
309 // If "/jre/lib/" appears at the right place in the path, then we
310 // assume libjvm.so is installed in a JDK and we use this path.
311 //
312 // Otherwise exit with message: "Could not create the Java virtual machine."
313 //
314 // The following extra steps are taken in the debugging version:
315 //
316 // If "/jre/lib/" does NOT appear at the right place in the path
317 // instead of exit check for $JAVA_HOME environment variable.
318 //
319 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>,
320 // then we append a fake suffix "hotspot/libjvm.so" to this path so
321 // it looks like libjvm.so is installed there
322 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so.
323 //
324 // Otherwise exit.
325 //
326 // Important note: if the location of libjvm.so changes this
327 // code needs to be changed accordingly.
328
329 // The next few definitions allow the code to be verbatim:
330 #define malloc(n) (char*)NEW_C_HEAP_ARRAY(char, (n), mtInternal)
331 #define getenv(n) ::getenv(n)
332
333 /*
334 * See ld(1):
335 * The linker uses the following search paths to locate required
336 * shared libraries:
337 * 1: ...
338 * ...
339 * 7: The default directories, normally /lib and /usr/lib.
340 */
341 #ifndef DEFAULT_LIBPATH
342 #define DEFAULT_LIBPATH "/lib:/usr/lib"
343 #endif
344
345 #define EXTENSIONS_DIR "/lib/ext"
346 #define ENDORSED_DIR "/lib/endorsed"
347 #define REG_DIR "/usr/java/packages"
348
349 #ifdef __APPLE__
350 #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions"
351 #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java"
352 const char *user_home_dir = get_home();
353 // the null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir
354 int system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) +
355 sizeof(SYS_EXTENSIONS_DIRS);
356 #endif
357
358 {
359 /* sysclasspath, java_home, dll_dir */
360 {
361 char *home_path;
362 char *dll_path;
363 char *pslash;
364 char buf[MAXPATHLEN];
365 os::jvm_path(buf, sizeof(buf));
366
367 // Found the full path to libjvm.so.
368 // Now cut the path to <java_home>/jre if we can.
369 *(strrchr(buf, '/')) = '\0'; /* get rid of /libjvm.so */
370 pslash = strrchr(buf, '/');
371 if (pslash != NULL)
372 *pslash = '\0'; /* get rid of /{client|server|hotspot} */
373 dll_path = malloc(strlen(buf) + 1);
374 if (dll_path == NULL)
375 return;
376 strcpy(dll_path, buf);
377 Arguments::set_dll_dir(dll_path);
378
379 if (pslash != NULL) {
380 pslash = strrchr(buf, '/');
381 if (pslash != NULL) {
382 *pslash = '\0'; /* get rid of /<arch> (/lib on macosx) */
383 #ifndef __APPLE__
384 pslash = strrchr(buf, '/');
385 if (pslash != NULL)
386 *pslash = '\0'; /* get rid of /lib */
387 #endif
388 }
389 }
390
391 home_path = malloc(strlen(buf) + 1);
392 if (home_path == NULL)
393 return;
394 strcpy(home_path, buf);
395 Arguments::set_java_home(home_path);
396
397 if (!set_boot_path('/', ':'))
398 return;
399 }
400
401 /*
402 * Where to look for native libraries
403 *
404 * Note: Due to a legacy implementation, most of the library path
405 * is set in the launcher. This was to accomodate linking restrictions
406 * on legacy Bsd implementations (which are no longer supported).
407 * Eventually, all the library path setting will be done here.
408 *
409 * However, to prevent the proliferation of improperly built native
410 * libraries, the new path component /usr/java/packages is added here.
411 * Eventually, all the library path setting will be done here.
412 */
413 {
414 char *ld_library_path;
415
416 /*
417 * Construct the invariant part of ld_library_path. Note that the
418 * space for the colon and the trailing null are provided by the
419 * nulls included by the sizeof operator (so actually we allocate
420 * a byte more than necessary).
421 */
422 #ifdef __APPLE__
423 ld_library_path = (char *) malloc(system_ext_size);
424 sprintf(ld_library_path, "%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS, user_home_dir);
425 #else
426 ld_library_path = (char *) malloc(sizeof(REG_DIR) + sizeof("/lib/") +
427 strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH));
428 sprintf(ld_library_path, REG_DIR "/lib/%s:" DEFAULT_LIBPATH, cpu_arch);
429 #endif
430
431 /*
432 * Get the user setting of LD_LIBRARY_PATH, and prepended it. It
433 * should always exist (until the legacy problem cited above is
434 * addressed).
435 */
436 #ifdef __APPLE__
437 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code can specify a directory inside an app wrapper
438 char *l = getenv("JAVA_LIBRARY_PATH");
439 if (l != NULL) {
440 char *t = ld_library_path;
441 /* That's +1 for the colon and +1 for the trailing '\0' */
442 ld_library_path = (char *) malloc(strlen(l) + 1 + strlen(t) + 1);
443 sprintf(ld_library_path, "%s:%s", l, t);
444 free(t);
445 }
446
447 char *v = getenv("DYLD_LIBRARY_PATH");
448 #else
449 char *v = getenv("LD_LIBRARY_PATH");
450 #endif
451 if (v != NULL) {
452 char *t = ld_library_path;
453 /* That's +1 for the colon and +1 for the trailing '\0' */
454 ld_library_path = (char *) malloc(strlen(v) + 1 + strlen(t) + 1);
455 sprintf(ld_library_path, "%s:%s", v, t);
456 free(t);
457 }
458
459 #ifdef __APPLE__
460 // Apple's Java6 has "." at the beginning of java.library.path.
461 // OpenJDK on Windows has "." at the end of java.library.path.
462 // OpenJDK on Linux and Solaris don't have "." in java.library.path
463 // at all. To ease the transition from Apple's Java6 to OpenJDK7,
464 // "." is appended to the end of java.library.path. Yes, this
465 // could cause a change in behavior, but Apple's Java6 behavior
466 // can be achieved by putting "." at the beginning of the
467 // JAVA_LIBRARY_PATH environment variable.
468 {
469 char *t = ld_library_path;
470 // that's +3 for appending ":." and the trailing '\0'
471 ld_library_path = (char *) malloc(strlen(t) + 3);
472 sprintf(ld_library_path, "%s:%s", t, ".");
473 free(t);
474 }
475 #endif
476
477 Arguments::set_library_path(ld_library_path);
478 }
479
480 /*
481 * Extensions directories.
482 *
483 * Note that the space for the colon and the trailing null are provided
484 * by the nulls included by the sizeof operator (so actually one byte more
485 * than necessary is allocated).
486 */
487 {
488 #ifdef __APPLE__
489 char *buf = malloc(strlen(Arguments::get_java_home()) +
490 sizeof(EXTENSIONS_DIR) + system_ext_size);
491 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":"
492 SYS_EXTENSIONS_DIRS, user_home_dir, Arguments::get_java_home());
493 #else
494 char *buf = malloc(strlen(Arguments::get_java_home()) +
495 sizeof(EXTENSIONS_DIR) + sizeof(REG_DIR) + sizeof(EXTENSIONS_DIR));
496 sprintf(buf, "%s" EXTENSIONS_DIR ":" REG_DIR EXTENSIONS_DIR,
497 Arguments::get_java_home());
498 #endif
499
500 Arguments::set_ext_dirs(buf);
501 }
502
503 /* Endorsed standards default directory. */
504 {
505 char * buf;
506 buf = malloc(strlen(Arguments::get_java_home()) + sizeof(ENDORSED_DIR));
507 sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home());
508 Arguments::set_endorsed_dirs(buf);
509 }
510 }
511
512 #ifdef __APPLE__
513 #undef SYS_EXTENSIONS_DIR
514 #endif
515 #undef malloc
516 #undef getenv
517 #undef EXTENSIONS_DIR
518 #undef ENDORSED_DIR
519
520 // Done
521 return;
522 }
523
524 ////////////////////////////////////////////////////////////////////////////////
525 // breakpoint support
526
527 void os::breakpoint() {
528 BREAKPOINT;
529 }
530
531 extern "C" void breakpoint() {
532 // use debugger to set breakpoint here
533 }
534
535 ////////////////////////////////////////////////////////////////////////////////
536 // signal support
537
538 debug_only(static bool signal_sets_initialized = false);
539 static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs;
540
541 bool os::Bsd::is_sig_ignored(int sig) {
542 struct sigaction oact;
543 sigaction(sig, (struct sigaction*)NULL, &oact);
544 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction)
545 : CAST_FROM_FN_PTR(void*, oact.sa_handler);
546 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN))
547 return true;
548 else
549 return false;
550 }
551
552 void os::Bsd::signal_sets_init() {
553 // Should also have an assertion stating we are still single-threaded.
554 assert(!signal_sets_initialized, "Already initialized");
555 // Fill in signals that are necessarily unblocked for all threads in
556 // the VM. Currently, we unblock the following signals:
557 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
558 // by -Xrs (=ReduceSignalUsage));
559 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
560 // other threads. The "ReduceSignalUsage" boolean tells us not to alter
561 // the dispositions or masks wrt these signals.
562 // Programs embedding the VM that want to use the above signals for their
563 // own purposes must, at this time, use the "-Xrs" option to prevent
564 // interference with shutdown hooks and BREAK_SIGNAL thread dumping.
565 // (See bug 4345157, and other related bugs).
566 // In reality, though, unblocking these signals is really a nop, since
567 // these signals are not blocked by default.
568 sigemptyset(&unblocked_sigs);
569 sigemptyset(&allowdebug_blocked_sigs);
570 sigaddset(&unblocked_sigs, SIGILL);
571 sigaddset(&unblocked_sigs, SIGSEGV);
572 sigaddset(&unblocked_sigs, SIGBUS);
573 sigaddset(&unblocked_sigs, SIGFPE);
574 sigaddset(&unblocked_sigs, SR_signum);
575
576 if (!ReduceSignalUsage) {
577 if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
578 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
579 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL);
580 }
581 if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
582 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
583 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL);
584 }
585 if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
586 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
587 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL);
588 }
589 }
590 // Fill in signals that are blocked by all but the VM thread.
591 sigemptyset(&vm_sigs);
592 if (!ReduceSignalUsage)
593 sigaddset(&vm_sigs, BREAK_SIGNAL);
594 debug_only(signal_sets_initialized = true);
595
596 }
597
598 // These are signals that are unblocked while a thread is running Java.
599 // (For some reason, they get blocked by default.)
600 sigset_t* os::Bsd::unblocked_signals() {
601 assert(signal_sets_initialized, "Not initialized");
602 return &unblocked_sigs;
603 }
604
605 // These are the signals that are blocked while a (non-VM) thread is
606 // running Java. Only the VM thread handles these signals.
607 sigset_t* os::Bsd::vm_signals() {
608 assert(signal_sets_initialized, "Not initialized");
609 return &vm_sigs;
610 }
611
612 // These are signals that are blocked during cond_wait to allow debugger in
613 sigset_t* os::Bsd::allowdebug_blocked_signals() {
614 assert(signal_sets_initialized, "Not initialized");
615 return &allowdebug_blocked_sigs;
616 }
617
618 void os::Bsd::hotspot_sigmask(Thread* thread) {
619
620 //Save caller's signal mask before setting VM signal mask
621 sigset_t caller_sigmask;
622 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
623
624 OSThread* osthread = thread->osthread();
625 osthread->set_caller_sigmask(caller_sigmask);
626
627 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL);
628
629 if (!ReduceSignalUsage) {
630 if (thread->is_VM_thread()) {
631 // Only the VM thread handles BREAK_SIGNAL ...
632 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
633 } else {
634 // ... all other threads block BREAK_SIGNAL
635 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
636 }
637 }
638 }
639
640
641 //////////////////////////////////////////////////////////////////////////////
642 // create new thread
643
644 static address highest_vm_reserved_address();
645
646 // check if it's safe to start a new thread
647 static bool _thread_safety_check(Thread* thread) {
648 return true;
649 }
650
651 #ifdef __APPLE__
652 // library handle for calling objc_registerThreadWithCollector()
653 // without static linking to the libobjc library
654 #define OBJC_LIB "/usr/lib/libobjc.dylib"
655 #define OBJC_GCREGISTER "objc_registerThreadWithCollector"
656 typedef void (*objc_registerThreadWithCollector_t)();
657 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction;
658 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL;
659 #endif
660
661 #ifdef __APPLE__
662 static uint64_t locate_unique_thread_id() {
663 // Additional thread_id used to correlate threads in SA
664 thread_identifier_info_data_t m_ident_info;
665 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT;
666
667 thread_info(::mach_thread_self(), THREAD_IDENTIFIER_INFO,
668 (thread_info_t) &m_ident_info, &count);
669 return m_ident_info.thread_id;
670 }
671 #endif
672
673 // Thread start routine for all newly created threads
674 static void *java_start(Thread *thread) {
675 // Try to randomize the cache line index of hot stack frames.
676 // This helps when threads of the same stack traces evict each other's
677 // cache lines. The threads can be either from the same JVM instance, or
678 // from different JVM instances. The benefit is especially true for
679 // processors with hyperthreading technology.
680 static int counter = 0;
681 int pid = os::current_process_id();
682 alloca(((pid ^ counter++) & 7) * 128);
683
684 ThreadLocalStorage::set_thread(thread);
685
686 OSThread* osthread = thread->osthread();
687 Monitor* sync = osthread->startThread_lock();
688
689 // non floating stack BsdThreads needs extra check, see above
690 if (!_thread_safety_check(thread)) {
691 // notify parent thread
692 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
693 osthread->set_state(ZOMBIE);
694 sync->notify_all();
695 return NULL;
696 }
697
698 #ifdef __APPLE__
699 // thread_id is mach thread on macos
700 osthread->set_thread_id(::mach_thread_self());
701 osthread->set_unique_thread_id(locate_unique_thread_id());
702 #else
703 // thread_id is pthread_id on BSD
704 osthread->set_thread_id(::pthread_self());
705 #endif
706 // initialize signal mask for this thread
707 os::Bsd::hotspot_sigmask(thread);
708
709 // initialize floating point control register
710 os::Bsd::init_thread_fpu_state();
711
712 #ifdef __APPLE__
713 // register thread with objc gc
714 if (objc_registerThreadWithCollectorFunction != NULL) {
715 objc_registerThreadWithCollectorFunction();
716 }
717 #endif
718
719 // handshaking with parent thread
720 {
721 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
722
723 // notify parent thread
724 osthread->set_state(INITIALIZED);
725 sync->notify_all();
726
727 // wait until os::start_thread()
728 while (osthread->get_state() == INITIALIZED) {
729 sync->wait(Mutex::_no_safepoint_check_flag);
730 }
731 }
732
733 // call one more level start routine
734 thread->run();
735
736 return 0;
737 }
738
739 bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) {
740 assert(thread->osthread() == NULL, "caller responsible");
741
742 // Allocate the OSThread object
743 OSThread* osthread = new OSThread(NULL, NULL);
744 if (osthread == NULL) {
745 return false;
746 }
747
748 // set the correct thread state
749 osthread->set_thread_type(thr_type);
750
751 // Initial state is ALLOCATED but not INITIALIZED
752 osthread->set_state(ALLOCATED);
753
754 thread->set_osthread(osthread);
755
756 // init thread attributes
757 pthread_attr_t attr;
758 pthread_attr_init(&attr);
759 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
760
761 // stack size
762 if (os::Bsd::supports_variable_stack_size()) {
763 // calculate stack size if it's not specified by caller
764 if (stack_size == 0) {
765 stack_size = os::Bsd::default_stack_size(thr_type);
766
767 switch (thr_type) {
768 case os::java_thread:
769 // Java threads use ThreadStackSize which default value can be
770 // changed with the flag -Xss
771 assert (JavaThread::stack_size_at_create() > 0, "this should be set");
772 stack_size = JavaThread::stack_size_at_create();
773 break;
774 case os::compiler_thread:
775 if (CompilerThreadStackSize > 0) {
776 stack_size = (size_t)(CompilerThreadStackSize * K);
777 break;
778 } // else fall through:
779 // use VMThreadStackSize if CompilerThreadStackSize is not defined
780 case os::vm_thread:
781 case os::pgc_thread:
782 case os::cgc_thread:
783 case os::watcher_thread:
784 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K);
785 break;
786 }
787 }
788
789 stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed);
790 pthread_attr_setstacksize(&attr, stack_size);
791 } else {
792 // let pthread_create() pick the default value.
793 }
794
795 ThreadState state;
796
797 {
798 pthread_t tid;
799 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread);
800
801 pthread_attr_destroy(&attr);
802
803 if (ret != 0) {
804 if (PrintMiscellaneous && (Verbose || WizardMode)) {
805 perror("pthread_create()");
806 }
807 // Need to clean up stuff we've allocated so far
808 thread->set_osthread(NULL);
809 delete osthread;
810 return false;
811 }
812
813 // Store pthread info into the OSThread
814 osthread->set_pthread_id(tid);
815
816 // Wait until child thread is either initialized or aborted
817 {
818 Monitor* sync_with_child = osthread->startThread_lock();
819 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
820 while ((state = osthread->get_state()) == ALLOCATED) {
821 sync_with_child->wait(Mutex::_no_safepoint_check_flag);
822 }
823 }
824
825 }
826
827 // Aborted due to thread limit being reached
828 if (state == ZOMBIE) {
829 thread->set_osthread(NULL);
830 delete osthread;
831 return false;
832 }
833
834 // The thread is returned suspended (in state INITIALIZED),
835 // and is started higher up in the call chain
836 assert(state == INITIALIZED, "race condition");
837 return true;
838 }
839
840 /////////////////////////////////////////////////////////////////////////////
841 // attach existing thread
842
843 // bootstrap the main thread
844 bool os::create_main_thread(JavaThread* thread) {
845 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
846 return create_attached_thread(thread);
847 }
848
849 bool os::create_attached_thread(JavaThread* thread) {
850 #ifdef ASSERT
851 thread->verify_not_published();
852 #endif
853
854 // Allocate the OSThread object
855 OSThread* osthread = new OSThread(NULL, NULL);
856
857 if (osthread == NULL) {
858 return false;
859 }
860
861 // Store pthread info into the OSThread
862 #ifdef __APPLE__
863 osthread->set_thread_id(::mach_thread_self());
864 osthread->set_unique_thread_id(locate_unique_thread_id());
865 #else
866 osthread->set_thread_id(::pthread_self());
867 #endif
868 osthread->set_pthread_id(::pthread_self());
869
870 // initialize floating point control register
871 os::Bsd::init_thread_fpu_state();
872
873 // Initial thread state is RUNNABLE
874 osthread->set_state(RUNNABLE);
875
876 thread->set_osthread(osthread);
877
878 // initialize signal mask for this thread
879 // and save the caller's signal mask
880 os::Bsd::hotspot_sigmask(thread);
881
882 return true;
883 }
884
885 void os::pd_start_thread(Thread* thread) {
886 OSThread * osthread = thread->osthread();
887 assert(osthread->get_state() != INITIALIZED, "just checking");
888 Monitor* sync_with_child = osthread->startThread_lock();
889 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
890 sync_with_child->notify();
891 }
892
893 // Free Bsd resources related to the OSThread
894 void os::free_thread(OSThread* osthread) {
895 assert(osthread != NULL, "osthread not set");
896
897 if (Thread::current()->osthread() == osthread) {
898 // Restore caller's signal mask
899 sigset_t sigmask = osthread->caller_sigmask();
900 pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
901 }
902
903 delete osthread;
904 }
905
906 //////////////////////////////////////////////////////////////////////////////
907 // thread local storage
908
909 int os::allocate_thread_local_storage() {
910 pthread_key_t key;
911 int rslt = pthread_key_create(&key, NULL);
912 assert(rslt == 0, "cannot allocate thread local storage");
913 return (int)key;
914 }
915
916 // Note: This is currently not used by VM, as we don't destroy TLS key
917 // on VM exit.
918 void os::free_thread_local_storage(int index) {
919 int rslt = pthread_key_delete((pthread_key_t)index);
920 assert(rslt == 0, "invalid index");
921 }
922
923 void os::thread_local_storage_at_put(int index, void* value) {
924 int rslt = pthread_setspecific((pthread_key_t)index, value);
925 assert(rslt == 0, "pthread_setspecific failed");
926 }
927
928 extern "C" Thread* get_thread() {
929 return ThreadLocalStorage::thread();
930 }
931
932
933 ////////////////////////////////////////////////////////////////////////////////
934 // time support
935
936 // Time since start-up in seconds to a fine granularity.
937 // Used by VMSelfDestructTimer and the MemProfiler.
938 double os::elapsedTime() {
939
940 return (double)(os::elapsed_counter()) * 0.000001;
941 }
942
943 jlong os::elapsed_counter() {
944 timeval time;
945 int status = gettimeofday(&time, NULL);
946 return jlong(time.tv_sec) * 1000 * 1000 + jlong(time.tv_usec) - initial_time_count;
947 }
948
949 jlong os::elapsed_frequency() {
950 return (1000 * 1000);
951 }
952
953 // XXX: For now, code this as if BSD does not support vtime.
954 bool os::supports_vtime() { return false; }
955 bool os::enable_vtime() { return false; }
956 bool os::vtime_enabled() { return false; }
957 double os::elapsedVTime() {
958 // better than nothing, but not much
959 return elapsedTime();
960 }
961
962 jlong os::javaTimeMillis() {
963 timeval time;
964 int status = gettimeofday(&time, NULL);
965 assert(status != -1, "bsd error");
966 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
967 }
968
969 #ifndef CLOCK_MONOTONIC
970 #define CLOCK_MONOTONIC (1)
971 #endif
972
973 #ifdef __APPLE__
974 void os::Bsd::clock_init() {
975 // XXXDARWIN: Investigate replacement monotonic clock
976 }
977 #else
978 void os::Bsd::clock_init() {
979 struct timespec res;
980 struct timespec tp;
981 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
982 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) {
983 // yes, monotonic clock is supported
984 _clock_gettime = ::clock_gettime;
985 }
986 }
987 #endif
988
989
990 jlong os::javaTimeNanos() {
991 if (Bsd::supports_monotonic_clock()) {
992 struct timespec tp;
993 int status = Bsd::clock_gettime(CLOCK_MONOTONIC, &tp);
994 assert(status == 0, "gettime error");
995 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
996 return result;
997 } else {
998 timeval time;
999 int status = gettimeofday(&time, NULL);
1000 assert(status != -1, "bsd error");
1001 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
1002 return 1000 * usecs;
1003 }
1004 }
1005
1006 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
1007 if (Bsd::supports_monotonic_clock()) {
1008 info_ptr->max_value = ALL_64_BITS;
1009
1010 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
1011 info_ptr->may_skip_backward = false; // not subject to resetting or drifting
1012 info_ptr->may_skip_forward = false; // not subject to resetting or drifting
1013 } else {
1014 // gettimeofday - based on time in seconds since the Epoch thus does not wrap
1015 info_ptr->max_value = ALL_64_BITS;
1016
1017 // gettimeofday is a real time clock so it skips
1018 info_ptr->may_skip_backward = true;
1019 info_ptr->may_skip_forward = true;
1020 }
1021
1022 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
1023 }
1024
1025 // Return the real, user, and system times in seconds from an
1026 // arbitrary fixed point in the past.
1027 bool os::getTimesSecs(double* process_real_time,
1028 double* process_user_time,
1029 double* process_system_time) {
1030 struct tms ticks;
1031 clock_t real_ticks = times(&ticks);
1032
1033 if (real_ticks == (clock_t) (-1)) {
1034 return false;
1035 } else {
1036 double ticks_per_second = (double) clock_tics_per_sec;
1037 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1038 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1039 *process_real_time = ((double) real_ticks) / ticks_per_second;
1040
1041 return true;
1042 }
1043 }
1044
1045
1046 char * os::local_time_string(char *buf, size_t buflen) {
1047 struct tm t;
1048 time_t long_time;
1049 time(&long_time);
1050 localtime_r(&long_time, &t);
1051 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1052 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1053 t.tm_hour, t.tm_min, t.tm_sec);
1054 return buf;
1055 }
1056
1057 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
1058 return localtime_r(clock, res);
1059 }
1060
1061 ////////////////////////////////////////////////////////////////////////////////
1062 // runtime exit support
1063
1064 // Note: os::shutdown() might be called very early during initialization, or
1065 // called from signal handler. Before adding something to os::shutdown(), make
1066 // sure it is async-safe and can handle partially initialized VM.
1067 void os::shutdown() {
1068
1069 // allow PerfMemory to attempt cleanup of any persistent resources
1070 perfMemory_exit();
1071
1072 // needs to remove object in file system
1073 AttachListener::abort();
1074
1075 // flush buffered output, finish log files
1076 ostream_abort();
1077
1078 // Check for abort hook
1079 abort_hook_t abort_hook = Arguments::abort_hook();
1080 if (abort_hook != NULL) {
1081 abort_hook();
1082 }
1083
1084 }
1085
1086 // Note: os::abort() might be called very early during initialization, or
1087 // called from signal handler. Before adding something to os::abort(), make
1088 // sure it is async-safe and can handle partially initialized VM.
1089 void os::abort(bool dump_core) {
1090 os::shutdown();
1091 if (dump_core) {
1092 #ifndef PRODUCT
1093 fdStream out(defaultStream::output_fd());
1094 out.print_raw("Current thread is ");
1095 char buf[16];
1096 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
1097 out.print_raw_cr(buf);
1098 out.print_raw_cr("Dumping core ...");
1099 #endif
1100 ::abort(); // dump core
1101 }
1102
1103 ::exit(1);
1104 }
1105
1106 // Die immediately, no exit hook, no abort hook, no cleanup.
1107 void os::die() {
1108 // _exit() on BsdThreads only kills current thread
1109 ::abort();
1110 }
1111
1112 // unused on bsd for now.
1113 void os::set_error_file(const char *logfile) {}
1114
1115
1116 // This method is a copy of JDK's sysGetLastErrorString
1117 // from src/solaris/hpi/src/system_md.c
1118
1119 size_t os::lasterror(char *buf, size_t len) {
1120
1121 if (errno == 0) return 0;
1122
1123 const char *s = ::strerror(errno);
1124 size_t n = ::strlen(s);
1125 if (n >= len) {
1126 n = len - 1;
1127 }
1128 ::strncpy(buf, s, n);
1129 buf[n] = '\0';
1130 return n;
1131 }
1132
1133 intx os::current_thread_id() {
1134 #ifdef __APPLE__
1135 return (intx)::mach_thread_self();
1136 #else
1137 return (intx)::pthread_self();
1138 #endif
1139 }
1140 int os::current_process_id() {
1141
1142 // Under the old bsd thread library, bsd gives each thread
1143 // its own process id. Because of this each thread will return
1144 // a different pid if this method were to return the result
1145 // of getpid(2). Bsd provides no api that returns the pid
1146 // of the launcher thread for the vm. This implementation
1147 // returns a unique pid, the pid of the launcher thread
1148 // that starts the vm 'process'.
1149
1150 // Under the NPTL, getpid() returns the same pid as the
1151 // launcher thread rather than a unique pid per thread.
1152 // Use gettid() if you want the old pre NPTL behaviour.
1153
1154 // if you are looking for the result of a call to getpid() that
1155 // returns a unique pid for the calling thread, then look at the
1156 // OSThread::thread_id() method in osThread_bsd.hpp file
1157
1158 return (int)(_initial_pid ? _initial_pid : getpid());
1159 }
1160
1161 // DLL functions
1162
1163 #define JNI_LIB_PREFIX "lib"
1164 #ifdef __APPLE__
1165 #define JNI_LIB_SUFFIX ".dylib"
1166 #else
1167 #define JNI_LIB_SUFFIX ".so"
1168 #endif
1169
1170 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1171
1172 // This must be hard coded because it's the system's temporary
1173 // directory not the java application's temp directory, ala java.io.tmpdir.
1174 #ifdef __APPLE__
1175 // macosx has a secure per-user temporary directory
1176 char temp_path_storage[PATH_MAX];
1177 const char* os::get_temp_directory() {
1178 static char *temp_path = NULL;
1179 if (temp_path == NULL) {
1180 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
1181 if (pathSize == 0 || pathSize > PATH_MAX) {
1182 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
1183 }
1184 temp_path = temp_path_storage;
1185 }
1186 return temp_path;
1187 }
1188 #else /* __APPLE__ */
1189 const char* os::get_temp_directory() { return "/tmp"; }
1190 #endif /* __APPLE__ */
1191
1192 static bool file_exists(const char* filename) {
1193 struct stat statbuf;
1194 if (filename == NULL || strlen(filename) == 0) {
1195 return false;
1196 }
1197 return os::stat(filename, &statbuf) == 0;
1198 }
1199
1200 bool os::dll_build_name(char* buffer, size_t buflen,
1201 const char* pname, const char* fname) {
1202 bool retval = false;
1203 // Copied from libhpi
1204 const size_t pnamelen = pname ? strlen(pname) : 0;
1205
1206 // Return error on buffer overflow.
1207 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) {
1208 return retval;
1209 }
1210
1211 if (pnamelen == 0) {
1212 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname);
1213 retval = true;
1214 } else if (strchr(pname, *os::path_separator()) != NULL) {
1215 int n;
1216 char** pelements = split_path(pname, &n);
1217 for (int i = 0 ; i < n ; i++) {
1218 // Really shouldn't be NULL, but check can't hurt
1219 if (pelements[i] == NULL || strlen(pelements[i]) == 0) {
1220 continue; // skip the empty path values
1221 }
1222 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX,
1223 pelements[i], fname);
1224 if (file_exists(buffer)) {
1225 retval = true;
1226 break;
1227 }
1228 }
1229 // release the storage
1230 for (int i = 0 ; i < n ; i++) {
1231 if (pelements[i] != NULL) {
1232 FREE_C_HEAP_ARRAY(char, pelements[i], mtInternal);
1233 }
1234 }
1235 if (pelements != NULL) {
1236 FREE_C_HEAP_ARRAY(char*, pelements, mtInternal);
1237 }
1238 } else {
1239 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname);
1240 retval = true;
1241 }
1242 return retval;
1243 }
1244
1245 const char* os::get_current_directory(char *buf, int buflen) {
1246 return getcwd(buf, buflen);
1247 }
1248
1249 // check if addr is inside libjvm.so
1250 bool os::address_is_in_vm(address addr) {
1251 static address libjvm_base_addr;
1252 Dl_info dlinfo;
1253
1254 if (libjvm_base_addr == NULL) {
1255 dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo);
1256 libjvm_base_addr = (address)dlinfo.dli_fbase;
1257 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1258 }
1259
1260 if (dladdr((void *)addr, &dlinfo)) {
1261 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1262 }
1263
1264 return false;
1265 }
1266
1267
1268 #define MACH_MAXSYMLEN 256
1269
1270 bool os::dll_address_to_function_name(address addr, char *buf,
1271 int buflen, int *offset) {
1272 Dl_info dlinfo;
1273 char localbuf[MACH_MAXSYMLEN];
1274
1275 // dladdr will find names of dynamic functions only, but does
1276 // it set dli_fbase with mach_header address when it "fails" ?
1277 if (dladdr((void*)addr, &dlinfo) && dlinfo.dli_sname != NULL) {
1278 if (buf != NULL) {
1279 if(!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) {
1280 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1281 }
1282 }
1283 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1284 return true;
1285 } else if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != 0) {
1286 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1287 buf, buflen, offset, dlinfo.dli_fname)) {
1288 return true;
1289 }
1290 }
1291
1292 // Handle non-dymanic manually:
1293 if (dlinfo.dli_fbase != NULL &&
1294 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset, dlinfo.dli_fbase)) {
1295 if(!Decoder::demangle(localbuf, buf, buflen)) {
1296 jio_snprintf(buf, buflen, "%s", localbuf);
1297 }
1298 return true;
1299 }
1300 if (buf != NULL) 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 Dl_info dlinfo;
1309
1310 if (dladdr((void*)addr, &dlinfo)){
1311 if (buf) jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1312 if (offset) *offset = addr - (address)dlinfo.dli_fbase;
1313 return true;
1314 } else {
1315 if (buf) buf[0] = '\0';
1316 if (offset) *offset = -1;
1317 return false;
1318 }
1319 }
1320
1321 // Loads .dll/.so and
1322 // in case of error it checks if .dll/.so was built for the
1323 // same architecture as Hotspot is running on
1324
1325 #ifdef __APPLE__
1326 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1327 void * result= ::dlopen(filename, RTLD_LAZY);
1328 if (result != NULL) {
1329 // Successful loading
1330 return result;
1331 }
1332
1333 // Read system error message into ebuf
1334 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1335 ebuf[ebuflen-1]='\0';
1336
1337 return NULL;
1338 }
1339 #else
1340 void * os::dll_load(const char *filename, char *ebuf, int ebuflen)
1341 {
1342 void * result= ::dlopen(filename, RTLD_LAZY);
1343 if (result != NULL) {
1344 // Successful loading
1345 return result;
1346 }
1347
1348 Elf32_Ehdr elf_head;
1349
1350 // Read system error message into ebuf
1351 // It may or may not be overwritten below
1352 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1353 ebuf[ebuflen-1]='\0';
1354 int diag_msg_max_length=ebuflen-strlen(ebuf);
1355 char* diag_msg_buf=ebuf+strlen(ebuf);
1356
1357 if (diag_msg_max_length==0) {
1358 // No more space in ebuf for additional diagnostics message
1359 return NULL;
1360 }
1361
1362
1363 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1364
1365 if (file_descriptor < 0) {
1366 // Can't open library, report dlerror() message
1367 return NULL;
1368 }
1369
1370 bool failed_to_read_elf_head=
1371 (sizeof(elf_head)!=
1372 (::read(file_descriptor, &elf_head,sizeof(elf_head)))) ;
1373
1374 ::close(file_descriptor);
1375 if (failed_to_read_elf_head) {
1376 // file i/o error - report dlerror() msg
1377 return NULL;
1378 }
1379
1380 typedef struct {
1381 Elf32_Half code; // Actual value as defined in elf.h
1382 Elf32_Half compat_class; // Compatibility of archs at VM's sense
1383 char elf_class; // 32 or 64 bit
1384 char endianess; // MSB or LSB
1385 char* name; // String representation
1386 } arch_t;
1387
1388 #ifndef EM_486
1389 #define EM_486 6 /* Intel 80486 */
1390 #endif
1391
1392 #ifndef EM_MIPS_RS3_LE
1393 #define EM_MIPS_RS3_LE 10 /* MIPS */
1394 #endif
1395
1396 #ifndef EM_PPC64
1397 #define EM_PPC64 21 /* PowerPC64 */
1398 #endif
1399
1400 #ifndef EM_S390
1401 #define EM_S390 22 /* IBM System/390 */
1402 #endif
1403
1404 #ifndef EM_IA_64
1405 #define EM_IA_64 50 /* HP/Intel IA-64 */
1406 #endif
1407
1408 #ifndef EM_X86_64
1409 #define EM_X86_64 62 /* AMD x86-64 */
1410 #endif
1411
1412 static const arch_t arch_array[]={
1413 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1414 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1415 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
1416 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
1417 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1418 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1419 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
1420 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
1421 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
1422 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"},
1423 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
1424 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
1425 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
1426 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
1427 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
1428 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
1429 };
1430
1431 #if (defined IA32)
1432 static Elf32_Half running_arch_code=EM_386;
1433 #elif (defined AMD64)
1434 static Elf32_Half running_arch_code=EM_X86_64;
1435 #elif (defined IA64)
1436 static Elf32_Half running_arch_code=EM_IA_64;
1437 #elif (defined __sparc) && (defined _LP64)
1438 static Elf32_Half running_arch_code=EM_SPARCV9;
1439 #elif (defined __sparc) && (!defined _LP64)
1440 static Elf32_Half running_arch_code=EM_SPARC;
1441 #elif (defined __powerpc64__)
1442 static Elf32_Half running_arch_code=EM_PPC64;
1443 #elif (defined __powerpc__)
1444 static Elf32_Half running_arch_code=EM_PPC;
1445 #elif (defined ARM)
1446 static Elf32_Half running_arch_code=EM_ARM;
1447 #elif (defined S390)
1448 static Elf32_Half running_arch_code=EM_S390;
1449 #elif (defined ALPHA)
1450 static Elf32_Half running_arch_code=EM_ALPHA;
1451 #elif (defined MIPSEL)
1452 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
1453 #elif (defined PARISC)
1454 static Elf32_Half running_arch_code=EM_PARISC;
1455 #elif (defined MIPS)
1456 static Elf32_Half running_arch_code=EM_MIPS;
1457 #elif (defined M68K)
1458 static Elf32_Half running_arch_code=EM_68K;
1459 #else
1460 #error Method os::dll_load requires that one of following is defined:\
1461 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
1462 #endif
1463
1464 // Identify compatability class for VM's architecture and library's architecture
1465 // Obtain string descriptions for architectures
1466
1467 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
1468 int running_arch_index=-1;
1469
1470 for (unsigned int i=0 ; i < ARRAY_SIZE(arch_array) ; i++ ) {
1471 if (running_arch_code == arch_array[i].code) {
1472 running_arch_index = i;
1473 }
1474 if (lib_arch.code == arch_array[i].code) {
1475 lib_arch.compat_class = arch_array[i].compat_class;
1476 lib_arch.name = arch_array[i].name;
1477 }
1478 }
1479
1480 assert(running_arch_index != -1,
1481 "Didn't find running architecture code (running_arch_code) in arch_array");
1482 if (running_arch_index == -1) {
1483 // Even though running architecture detection failed
1484 // we may still continue with reporting dlerror() message
1485 return NULL;
1486 }
1487
1488 if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
1489 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
1490 return NULL;
1491 }
1492
1493 #ifndef S390
1494 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
1495 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
1496 return NULL;
1497 }
1498 #endif // !S390
1499
1500 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
1501 if ( lib_arch.name!=NULL ) {
1502 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1503 " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
1504 lib_arch.name, arch_array[running_arch_index].name);
1505 } else {
1506 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1507 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
1508 lib_arch.code,
1509 arch_array[running_arch_index].name);
1510 }
1511 }
1512
1513 return NULL;
1514 }
1515 #endif /* !__APPLE__ */
1516
1517 // XXX: Do we need a lock around this as per Linux?
1518 void* os::dll_lookup(void* handle, const char* name) {
1519 return dlsym(handle, name);
1520 }
1521
1522
1523 static bool _print_ascii_file(const char* filename, outputStream* st) {
1524 int fd = ::open(filename, O_RDONLY);
1525 if (fd == -1) {
1526 return false;
1527 }
1528
1529 char buf[32];
1530 int bytes;
1531 while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) {
1532 st->print_raw(buf, bytes);
1533 }
1534
1535 ::close(fd);
1536
1537 return true;
1538 }
1539
1540 void os::print_dll_info(outputStream *st) {
1541 st->print_cr("Dynamic libraries:");
1542 #ifdef RTLD_DI_LINKMAP
1543 Dl_info dli;
1544 void *handle;
1545 Link_map *map;
1546 Link_map *p;
1547
1548 if (!dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli)) {
1549 st->print_cr("Error: Cannot print dynamic libraries.");
1550 return;
1551 }
1552 handle = dlopen(dli.dli_fname, RTLD_LAZY);
1553 if (handle == NULL) {
1554 st->print_cr("Error: Cannot print dynamic libraries.");
1555 return;
1556 }
1557 dlinfo(handle, RTLD_DI_LINKMAP, &map);
1558 if (map == NULL) {
1559 st->print_cr("Error: Cannot print dynamic libraries.");
1560 return;
1561 }
1562
1563 while (map->l_prev != NULL)
1564 map = map->l_prev;
1565
1566 while (map != NULL) {
1567 st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name);
1568 map = map->l_next;
1569 }
1570
1571 dlclose(handle);
1572 #elif defined(__APPLE__)
1573 uint32_t count;
1574 uint32_t i;
1575
1576 count = _dyld_image_count();
1577 for (i = 1; i < count; i++) {
1578 const char *name = _dyld_get_image_name(i);
1579 intptr_t slide = _dyld_get_image_vmaddr_slide(i);
1580 st->print_cr(PTR_FORMAT " \t%s", slide, name);
1581 }
1582 #else
1583 st->print_cr("Error: Cannot print dynamic libraries.");
1584 #endif
1585 }
1586
1587 void os::print_os_info_brief(outputStream* st) {
1588 st->print("Bsd");
1589
1590 os::Posix::print_uname_info(st);
1591 }
1592
1593 void os::print_os_info(outputStream* st) {
1594 st->print("OS:");
1595 st->print("Bsd");
1596
1597 os::Posix::print_uname_info(st);
1598
1599 os::Posix::print_rlimit_info(st);
1600
1601 os::Posix::print_load_average(st);
1602 }
1603
1604 void os::pd_print_cpu_info(outputStream* st) {
1605 // Nothing to do for now.
1606 }
1607
1608 void os::print_memory_info(outputStream* st) {
1609
1610 st->print("Memory:");
1611 st->print(" %dk page", os::vm_page_size()>>10);
1612
1613 st->print(", physical " UINT64_FORMAT "k",
1614 os::physical_memory() >> 10);
1615 st->print("(" UINT64_FORMAT "k free)",
1616 os::available_memory() >> 10);
1617 st->cr();
1618
1619 // meminfo
1620 st->print("\n/proc/meminfo:\n");
1621 _print_ascii_file("/proc/meminfo", st);
1622 st->cr();
1623 }
1624
1625 // Taken from /usr/include/bits/siginfo.h Supposed to be architecture specific
1626 // but they're the same for all the bsd arch that we support
1627 // and they're the same for solaris but there's no common place to put this.
1628 const char *ill_names[] = { "ILL0", "ILL_ILLOPC", "ILL_ILLOPN", "ILL_ILLADR",
1629 "ILL_ILLTRP", "ILL_PRVOPC", "ILL_PRVREG",
1630 "ILL_COPROC", "ILL_BADSTK" };
1631
1632 const char *fpe_names[] = { "FPE0", "FPE_INTDIV", "FPE_INTOVF", "FPE_FLTDIV",
1633 "FPE_FLTOVF", "FPE_FLTUND", "FPE_FLTRES",
1634 "FPE_FLTINV", "FPE_FLTSUB", "FPE_FLTDEN" };
1635
1636 const char *segv_names[] = { "SEGV0", "SEGV_MAPERR", "SEGV_ACCERR" };
1637
1638 const char *bus_names[] = { "BUS0", "BUS_ADRALN", "BUS_ADRERR", "BUS_OBJERR" };
1639
1640 void os::print_siginfo(outputStream* st, void* siginfo) {
1641 st->print("siginfo:");
1642
1643 const int buflen = 100;
1644 char buf[buflen];
1645 siginfo_t *si = (siginfo_t*)siginfo;
1646 st->print("si_signo=%s: ", os::exception_name(si->si_signo, buf, buflen));
1647 if (si->si_errno != 0 && strerror_r(si->si_errno, buf, buflen) == 0) {
1648 st->print("si_errno=%s", buf);
1649 } else {
1650 st->print("si_errno=%d", si->si_errno);
1651 }
1652 const int c = si->si_code;
1653 assert(c > 0, "unexpected si_code");
1654 switch (si->si_signo) {
1655 case SIGILL:
1656 st->print(", si_code=%d (%s)", c, c > 8 ? "" : ill_names[c]);
1657 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1658 break;
1659 case SIGFPE:
1660 st->print(", si_code=%d (%s)", c, c > 9 ? "" : fpe_names[c]);
1661 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1662 break;
1663 case SIGSEGV:
1664 st->print(", si_code=%d (%s)", c, c > 2 ? "" : segv_names[c]);
1665 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1666 break;
1667 case SIGBUS:
1668 st->print(", si_code=%d (%s)", c, c > 3 ? "" : bus_names[c]);
1669 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1670 break;
1671 default:
1672 st->print(", si_code=%d", si->si_code);
1673 // no si_addr
1674 }
1675
1676 if ((si->si_signo == SIGBUS || si->si_signo == SIGSEGV) &&
1677 UseSharedSpaces) {
1678 FileMapInfo* mapinfo = FileMapInfo::current_info();
1679 if (mapinfo->is_in_shared_space(si->si_addr)) {
1680 st->print("\n\nError accessing class data sharing archive." \
1681 " Mapped file inaccessible during execution, " \
1682 " possible disk/network problem.");
1683 }
1684 }
1685 st->cr();
1686 }
1687
1688
1689 static void print_signal_handler(outputStream* st, int sig,
1690 char* buf, size_t buflen);
1691
1692 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1693 st->print_cr("Signal Handlers:");
1694 print_signal_handler(st, SIGSEGV, buf, buflen);
1695 print_signal_handler(st, SIGBUS , buf, buflen);
1696 print_signal_handler(st, SIGFPE , buf, buflen);
1697 print_signal_handler(st, SIGPIPE, buf, buflen);
1698 print_signal_handler(st, SIGXFSZ, buf, buflen);
1699 print_signal_handler(st, SIGILL , buf, buflen);
1700 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen);
1701 print_signal_handler(st, SR_signum, buf, buflen);
1702 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1703 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1704 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1705 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1706 }
1707
1708 static char saved_jvm_path[MAXPATHLEN] = {0};
1709
1710 // Find the full path to the current module, libjvm
1711 void os::jvm_path(char *buf, jint buflen) {
1712 // Error checking.
1713 if (buflen < MAXPATHLEN) {
1714 assert(false, "must use a large-enough buffer");
1715 buf[0] = '\0';
1716 return;
1717 }
1718 // Lazy resolve the path to current module.
1719 if (saved_jvm_path[0] != 0) {
1720 strcpy(buf, saved_jvm_path);
1721 return;
1722 }
1723
1724 char dli_fname[MAXPATHLEN];
1725 bool ret = dll_address_to_library_name(
1726 CAST_FROM_FN_PTR(address, os::jvm_path),
1727 dli_fname, sizeof(dli_fname), NULL);
1728 assert(ret != 0, "cannot locate libjvm");
1729 char *rp = realpath(dli_fname, buf);
1730 if (rp == NULL)
1731 return;
1732
1733 if (Arguments::created_by_gamma_launcher()) {
1734 // Support for the gamma launcher. Typical value for buf is
1735 // "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm". If "/jre/lib/" appears at
1736 // the right place in the string, then assume we are installed in a JDK and
1737 // we're done. Otherwise, check for a JAVA_HOME environment variable and
1738 // construct a path to the JVM being overridden.
1739
1740 const char *p = buf + strlen(buf) - 1;
1741 for (int count = 0; p > buf && count < 5; ++count) {
1742 for (--p; p > buf && *p != '/'; --p)
1743 /* empty */ ;
1744 }
1745
1746 if (strncmp(p, "/jre/lib/", 9) != 0) {
1747 // Look for JAVA_HOME in the environment.
1748 char* java_home_var = ::getenv("JAVA_HOME");
1749 if (java_home_var != NULL && java_home_var[0] != 0) {
1750 char* jrelib_p;
1751 int len;
1752
1753 // Check the current module name "libjvm"
1754 p = strrchr(buf, '/');
1755 assert(strstr(p, "/libjvm") == p, "invalid library name");
1756
1757 rp = realpath(java_home_var, buf);
1758 if (rp == NULL)
1759 return;
1760
1761 // determine if this is a legacy image or modules image
1762 // modules image doesn't have "jre" subdirectory
1763 len = strlen(buf);
1764 jrelib_p = buf + len;
1765
1766 // Add the appropriate library subdir
1767 snprintf(jrelib_p, buflen-len, "/jre/lib");
1768 if (0 != access(buf, F_OK)) {
1769 snprintf(jrelib_p, buflen-len, "/lib");
1770 }
1771
1772 // Add the appropriate client or server subdir
1773 len = strlen(buf);
1774 jrelib_p = buf + len;
1775 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
1776 if (0 != access(buf, F_OK)) {
1777 snprintf(jrelib_p, buflen-len, "");
1778 }
1779
1780 // If the path exists within JAVA_HOME, add the JVM library name
1781 // to complete the path to JVM being overridden. Otherwise fallback
1782 // to the path to the current library.
1783 if (0 == access(buf, F_OK)) {
1784 // Use current module name "libjvm"
1785 len = strlen(buf);
1786 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
1787 } else {
1788 // Fall back to path of current library
1789 rp = realpath(dli_fname, buf);
1790 if (rp == NULL)
1791 return;
1792 }
1793 }
1794 }
1795 }
1796
1797 strcpy(saved_jvm_path, buf);
1798 }
1799
1800 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1801 // no prefix required, not even "_"
1802 }
1803
1804 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1805 // no suffix required
1806 }
1807
1808 ////////////////////////////////////////////////////////////////////////////////
1809 // sun.misc.Signal support
1810
1811 static volatile jint sigint_count = 0;
1812
1813 static void
1814 UserHandler(int sig, void *siginfo, void *context) {
1815 // 4511530 - sem_post is serialized and handled by the manager thread. When
1816 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
1817 // don't want to flood the manager thread with sem_post requests.
1818 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1)
1819 return;
1820
1821 // Ctrl-C is pressed during error reporting, likely because the error
1822 // handler fails to abort. Let VM die immediately.
1823 if (sig == SIGINT && is_error_reported()) {
1824 os::die();
1825 }
1826
1827 os::signal_notify(sig);
1828 }
1829
1830 void* os::user_handler() {
1831 return CAST_FROM_FN_PTR(void*, UserHandler);
1832 }
1833
1834 extern "C" {
1835 typedef void (*sa_handler_t)(int);
1836 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1837 }
1838
1839 void* os::signal(int signal_number, void* handler) {
1840 struct sigaction sigAct, oldSigAct;
1841
1842 sigfillset(&(sigAct.sa_mask));
1843 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
1844 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1845
1846 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1847 // -1 means registration failed
1848 return (void *)-1;
1849 }
1850
1851 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1852 }
1853
1854 void os::signal_raise(int signal_number) {
1855 ::raise(signal_number);
1856 }
1857
1858 /*
1859 * The following code is moved from os.cpp for making this
1860 * code platform specific, which it is by its very nature.
1861 */
1862
1863 // Will be modified when max signal is changed to be dynamic
1864 int os::sigexitnum_pd() {
1865 return NSIG;
1866 }
1867
1868 // a counter for each possible signal value
1869 static volatile jint pending_signals[NSIG+1] = { 0 };
1870
1871 // Bsd(POSIX) specific hand shaking semaphore.
1872 #ifdef __APPLE__
1873 static semaphore_t sig_sem;
1874 #define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value)
1875 #define SEM_WAIT(sem) semaphore_wait(sem);
1876 #define SEM_POST(sem) semaphore_signal(sem);
1877 #else
1878 static sem_t sig_sem;
1879 #define SEM_INIT(sem, value) sem_init(&sem, 0, value)
1880 #define SEM_WAIT(sem) sem_wait(&sem);
1881 #define SEM_POST(sem) sem_post(&sem);
1882 #endif
1883
1884 void os::signal_init_pd() {
1885 // Initialize signal structures
1886 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
1887
1888 // Initialize signal semaphore
1889 ::SEM_INIT(sig_sem, 0);
1890 }
1891
1892 void os::signal_notify(int sig) {
1893 Atomic::inc(&pending_signals[sig]);
1894 ::SEM_POST(sig_sem);
1895 }
1896
1897 static int check_pending_signals(bool wait) {
1898 Atomic::store(0, &sigint_count);
1899 for (;;) {
1900 for (int i = 0; i < NSIG + 1; i++) {
1901 jint n = pending_signals[i];
1902 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
1903 return i;
1904 }
1905 }
1906 if (!wait) {
1907 return -1;
1908 }
1909 JavaThread *thread = JavaThread::current();
1910 ThreadBlockInVM tbivm(thread);
1911
1912 bool threadIsSuspended;
1913 do {
1914 thread->set_suspend_equivalent();
1915 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
1916 ::SEM_WAIT(sig_sem);
1917
1918 // were we externally suspended while we were waiting?
1919 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
1920 if (threadIsSuspended) {
1921 //
1922 // The semaphore has been incremented, but while we were waiting
1923 // another thread suspended us. We don't want to continue running
1924 // while suspended because that would surprise the thread that
1925 // suspended us.
1926 //
1927 ::SEM_POST(sig_sem);
1928
1929 thread->java_suspend_self();
1930 }
1931 } while (threadIsSuspended);
1932 }
1933 }
1934
1935 int os::signal_lookup() {
1936 return check_pending_signals(false);
1937 }
1938
1939 int os::signal_wait() {
1940 return check_pending_signals(true);
1941 }
1942
1943 ////////////////////////////////////////////////////////////////////////////////
1944 // Virtual Memory
1945
1946 int os::vm_page_size() {
1947 // Seems redundant as all get out
1948 assert(os::Bsd::page_size() != -1, "must call os::init");
1949 return os::Bsd::page_size();
1950 }
1951
1952 // Solaris allocates memory by pages.
1953 int os::vm_allocation_granularity() {
1954 assert(os::Bsd::page_size() != -1, "must call os::init");
1955 return os::Bsd::page_size();
1956 }
1957
1958 // Rationale behind this function:
1959 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
1960 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
1961 // samples for JITted code. Here we create private executable mapping over the code cache
1962 // and then we can use standard (well, almost, as mapping can change) way to provide
1963 // info for the reporting script by storing timestamp and location of symbol
1964 void bsd_wrap_code(char* base, size_t size) {
1965 static volatile jint cnt = 0;
1966
1967 if (!UseOprofile) {
1968 return;
1969 }
1970
1971 char buf[PATH_MAX + 1];
1972 int num = Atomic::add(1, &cnt);
1973
1974 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
1975 os::get_temp_directory(), os::current_process_id(), num);
1976 unlink(buf);
1977
1978 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
1979
1980 if (fd != -1) {
1981 off_t rv = ::lseek(fd, size-2, SEEK_SET);
1982 if (rv != (off_t)-1) {
1983 if (::write(fd, "", 1) == 1) {
1984 mmap(base, size,
1985 PROT_READ|PROT_WRITE|PROT_EXEC,
1986 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
1987 }
1988 }
1989 ::close(fd);
1990 unlink(buf);
1991 }
1992 }
1993
1994 // NOTE: Bsd kernel does not really reserve the pages for us.
1995 // All it does is to check if there are enough free pages
1996 // left at the time of mmap(). This could be a potential
1997 // problem.
1998 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
1999 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
2000 #ifdef __OpenBSD__
2001 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2002 return ::mprotect(addr, size, prot) == 0;
2003 #else
2004 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
2005 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
2006 return res != (uintptr_t) MAP_FAILED;
2007 #endif
2008 }
2009
2010
2011 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
2012 bool exec) {
2013 return commit_memory(addr, size, exec);
2014 }
2015
2016 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
2017 }
2018
2019 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
2020 ::madvise(addr, bytes, MADV_DONTNEED);
2021 }
2022
2023 void os::numa_make_global(char *addr, size_t bytes) {
2024 }
2025
2026 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
2027 }
2028
2029 bool os::numa_topology_changed() { return false; }
2030
2031 size_t os::numa_get_groups_num() {
2032 return 1;
2033 }
2034
2035 int os::numa_get_group_id() {
2036 return 0;
2037 }
2038
2039 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
2040 if (size > 0) {
2041 ids[0] = 0;
2042 return 1;
2043 }
2044 return 0;
2045 }
2046
2047 bool os::get_page_info(char *start, page_info* info) {
2048 return false;
2049 }
2050
2051 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2052 return end;
2053 }
2054
2055
2056 bool os::pd_uncommit_memory(char* addr, size_t size) {
2057 #ifdef __OpenBSD__
2058 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2059 return ::mprotect(addr, size, PROT_NONE) == 0;
2060 #else
2061 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
2062 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
2063 return res != (uintptr_t) MAP_FAILED;
2064 #endif
2065 }
2066
2067 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2068 return os::commit_memory(addr, size);
2069 }
2070
2071 // If this is a growable mapping, remove the guard pages entirely by
2072 // munmap()ping them. If not, just call uncommit_memory().
2073 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2074 return os::uncommit_memory(addr, size);
2075 }
2076
2077 static address _highest_vm_reserved_address = NULL;
2078
2079 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2080 // at 'requested_addr'. If there are existing memory mappings at the same
2081 // location, however, they will be overwritten. If 'fixed' is false,
2082 // 'requested_addr' is only treated as a hint, the return value may or
2083 // may not start from the requested address. Unlike Bsd mmap(), this
2084 // function returns NULL to indicate failure.
2085 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2086 char * addr;
2087 int flags;
2088
2089 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2090 if (fixed) {
2091 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2092 flags |= MAP_FIXED;
2093 }
2094
2095 // Map uncommitted pages PROT_READ and PROT_WRITE, change access
2096 // to PROT_EXEC if executable when we commit the page.
2097 addr = (char*)::mmap(requested_addr, bytes, PROT_READ|PROT_WRITE,
2098 flags, -1, 0);
2099
2100 if (addr != MAP_FAILED) {
2101 // anon_mmap() should only get called during VM initialization,
2102 // don't need lock (actually we can skip locking even it can be called
2103 // from multiple threads, because _highest_vm_reserved_address is just a
2104 // hint about the upper limit of non-stack memory regions.)
2105 if ((address)addr + bytes > _highest_vm_reserved_address) {
2106 _highest_vm_reserved_address = (address)addr + bytes;
2107 }
2108 }
2109
2110 return addr == MAP_FAILED ? NULL : addr;
2111 }
2112
2113 // Don't update _highest_vm_reserved_address, because there might be memory
2114 // regions above addr + size. If so, releasing a memory region only creates
2115 // a hole in the address space, it doesn't help prevent heap-stack collision.
2116 //
2117 static int anon_munmap(char * addr, size_t size) {
2118 return ::munmap(addr, size) == 0;
2119 }
2120
2121 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
2122 size_t alignment_hint) {
2123 return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2124 }
2125
2126 bool os::pd_release_memory(char* addr, size_t size) {
2127 return anon_munmap(addr, size);
2128 }
2129
2130 static address highest_vm_reserved_address() {
2131 return _highest_vm_reserved_address;
2132 }
2133
2134 static bool bsd_mprotect(char* addr, size_t size, int prot) {
2135 // Bsd wants the mprotect address argument to be page aligned.
2136 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size());
2137
2138 // According to SUSv3, mprotect() should only be used with mappings
2139 // established by mmap(), and mmap() always maps whole pages. Unaligned
2140 // 'addr' likely indicates problem in the VM (e.g. trying to change
2141 // protection of malloc'ed or statically allocated memory). Check the
2142 // caller if you hit this assert.
2143 assert(addr == bottom, "sanity check");
2144
2145 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2146 return ::mprotect(bottom, size, prot) == 0;
2147 }
2148
2149 // Set protections specified
2150 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2151 bool is_committed) {
2152 unsigned int p = 0;
2153 switch (prot) {
2154 case MEM_PROT_NONE: p = PROT_NONE; break;
2155 case MEM_PROT_READ: p = PROT_READ; break;
2156 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
2157 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2158 default:
2159 ShouldNotReachHere();
2160 }
2161 // is_committed is unused.
2162 return bsd_mprotect(addr, bytes, p);
2163 }
2164
2165 bool os::guard_memory(char* addr, size_t size) {
2166 return bsd_mprotect(addr, size, PROT_NONE);
2167 }
2168
2169 bool os::unguard_memory(char* addr, size_t size) {
2170 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
2171 }
2172
2173 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
2174 return false;
2175 }
2176
2177 /*
2178 * Set the coredump_filter bits to include largepages in core dump (bit 6)
2179 *
2180 * From the coredump_filter documentation:
2181 *
2182 * - (bit 0) anonymous private memory
2183 * - (bit 1) anonymous shared memory
2184 * - (bit 2) file-backed private memory
2185 * - (bit 3) file-backed shared memory
2186 * - (bit 4) ELF header pages in file-backed private memory areas (it is
2187 * effective only if the bit 2 is cleared)
2188 * - (bit 5) hugetlb private memory
2189 * - (bit 6) hugetlb shared memory
2190 */
2191 static void set_coredump_filter(void) {
2192 FILE *f;
2193 long cdm;
2194
2195 if ((f = fopen("/proc/self/coredump_filter", "r+")) == NULL) {
2196 return;
2197 }
2198
2199 if (fscanf(f, "%lx", &cdm) != 1) {
2200 fclose(f);
2201 return;
2202 }
2203
2204 rewind(f);
2205
2206 if ((cdm & LARGEPAGES_BIT) == 0) {
2207 cdm |= LARGEPAGES_BIT;
2208 fprintf(f, "%#lx", cdm);
2209 }
2210
2211 fclose(f);
2212 }
2213
2214 // Large page support
2215
2216 static size_t _large_page_size = 0;
2217
2218 void os::large_page_init() {
2219 }
2220
2221
2222 char* os::reserve_memory_special(size_t bytes, char* req_addr, bool exec) {
2223 // "exec" is passed in but not used. Creating the shared image for
2224 // the code cache doesn't have an SHM_X executable permission to check.
2225 assert(UseLargePages && UseSHM, "only for SHM large pages");
2226
2227 key_t key = IPC_PRIVATE;
2228 char *addr;
2229
2230 bool warn_on_failure = UseLargePages &&
2231 (!FLAG_IS_DEFAULT(UseLargePages) ||
2232 !FLAG_IS_DEFAULT(LargePageSizeInBytes)
2233 );
2234 char msg[128];
2235
2236 // Create a large shared memory region to attach to based on size.
2237 // Currently, size is the total size of the heap
2238 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W);
2239 if (shmid == -1) {
2240 // Possible reasons for shmget failure:
2241 // 1. shmmax is too small for Java heap.
2242 // > check shmmax value: cat /proc/sys/kernel/shmmax
2243 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax
2244 // 2. not enough large page memory.
2245 // > check available large pages: cat /proc/meminfo
2246 // > increase amount of large pages:
2247 // echo new_value > /proc/sys/vm/nr_hugepages
2248 // Note 1: different Bsd may use different name for this property,
2249 // e.g. on Redhat AS-3 it is "hugetlb_pool".
2250 // Note 2: it's possible there's enough physical memory available but
2251 // they are so fragmented after a long run that they can't
2252 // coalesce into large pages. Try to reserve large pages when
2253 // the system is still "fresh".
2254 if (warn_on_failure) {
2255 jio_snprintf(msg, sizeof(msg), "Failed to reserve shared memory (errno = %d).", errno);
2256 warning(msg);
2257 }
2258 return NULL;
2259 }
2260
2261 // attach to the region
2262 addr = (char*)shmat(shmid, req_addr, 0);
2263 int err = errno;
2264
2265 // Remove shmid. If shmat() is successful, the actual shared memory segment
2266 // will be deleted when it's detached by shmdt() or when the process
2267 // terminates. If shmat() is not successful this will remove the shared
2268 // segment immediately.
2269 shmctl(shmid, IPC_RMID, NULL);
2270
2271 if ((intptr_t)addr == -1) {
2272 if (warn_on_failure) {
2273 jio_snprintf(msg, sizeof(msg), "Failed to attach shared memory (errno = %d).", err);
2274 warning(msg);
2275 }
2276 return NULL;
2277 }
2278
2279 // The memory is committed
2280 address pc = CALLER_PC;
2281 MemTracker::record_virtual_memory_reserve((address)addr, bytes, pc);
2282 MemTracker::record_virtual_memory_commit((address)addr, bytes, pc);
2283
2284 return addr;
2285 }
2286
2287 bool os::release_memory_special(char* base, size_t bytes) {
2288 // detaching the SHM segment will also delete it, see reserve_memory_special()
2289 int rslt = shmdt(base);
2290 if (rslt == 0) {
2291 MemTracker::record_virtual_memory_uncommit((address)base, bytes);
2292 MemTracker::record_virtual_memory_release((address)base, bytes);
2293 return true;
2294 } else {
2295 return false;
2296 }
2297
2298 }
2299
2300 size_t os::large_page_size() {
2301 return _large_page_size;
2302 }
2303
2304 // HugeTLBFS allows application to commit large page memory on demand;
2305 // with SysV SHM the entire memory region must be allocated as shared
2306 // memory.
2307 bool os::can_commit_large_page_memory() {
2308 return UseHugeTLBFS;
2309 }
2310
2311 bool os::can_execute_large_page_memory() {
2312 return UseHugeTLBFS;
2313 }
2314
2315 // Reserve memory at an arbitrary address, only if that area is
2316 // available (and not reserved for something else).
2317
2318 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2319 const int max_tries = 10;
2320 char* base[max_tries];
2321 size_t size[max_tries];
2322 const size_t gap = 0x000000;
2323
2324 // Assert only that the size is a multiple of the page size, since
2325 // that's all that mmap requires, and since that's all we really know
2326 // about at this low abstraction level. If we need higher alignment,
2327 // we can either pass an alignment to this method or verify alignment
2328 // in one of the methods further up the call chain. See bug 5044738.
2329 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2330
2331 // Repeatedly allocate blocks until the block is allocated at the
2332 // right spot. Give up after max_tries. Note that reserve_memory() will
2333 // automatically update _highest_vm_reserved_address if the call is
2334 // successful. The variable tracks the highest memory address every reserved
2335 // by JVM. It is used to detect heap-stack collision if running with
2336 // fixed-stack BsdThreads. Because here we may attempt to reserve more
2337 // space than needed, it could confuse the collision detecting code. To
2338 // solve the problem, save current _highest_vm_reserved_address and
2339 // calculate the correct value before return.
2340 address old_highest = _highest_vm_reserved_address;
2341
2342 // Bsd mmap allows caller to pass an address as hint; give it a try first,
2343 // if kernel honors the hint then we can return immediately.
2344 char * addr = anon_mmap(requested_addr, bytes, false);
2345 if (addr == requested_addr) {
2346 return requested_addr;
2347 }
2348
2349 if (addr != NULL) {
2350 // mmap() is successful but it fails to reserve at the requested address
2351 anon_munmap(addr, bytes);
2352 }
2353
2354 int i;
2355 for (i = 0; i < max_tries; ++i) {
2356 base[i] = reserve_memory(bytes);
2357
2358 if (base[i] != NULL) {
2359 // Is this the block we wanted?
2360 if (base[i] == requested_addr) {
2361 size[i] = bytes;
2362 break;
2363 }
2364
2365 // Does this overlap the block we wanted? Give back the overlapped
2366 // parts and try again.
2367
2368 size_t top_overlap = requested_addr + (bytes + gap) - base[i];
2369 if (top_overlap >= 0 && top_overlap < bytes) {
2370 unmap_memory(base[i], top_overlap);
2371 base[i] += top_overlap;
2372 size[i] = bytes - top_overlap;
2373 } else {
2374 size_t bottom_overlap = base[i] + bytes - requested_addr;
2375 if (bottom_overlap >= 0 && bottom_overlap < bytes) {
2376 unmap_memory(requested_addr, bottom_overlap);
2377 size[i] = bytes - bottom_overlap;
2378 } else {
2379 size[i] = bytes;
2380 }
2381 }
2382 }
2383 }
2384
2385 // Give back the unused reserved pieces.
2386
2387 for (int j = 0; j < i; ++j) {
2388 if (base[j] != NULL) {
2389 unmap_memory(base[j], size[j]);
2390 }
2391 }
2392
2393 if (i < max_tries) {
2394 _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes);
2395 return requested_addr;
2396 } else {
2397 _highest_vm_reserved_address = old_highest;
2398 return NULL;
2399 }
2400 }
2401
2402 size_t os::read(int fd, void *buf, unsigned int nBytes) {
2403 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes));
2404 }
2405
2406 // TODO-FIXME: reconcile Solaris' os::sleep with the bsd variation.
2407 // Solaris uses poll(), bsd uses park().
2408 // Poll() is likely a better choice, assuming that Thread.interrupt()
2409 // generates a SIGUSRx signal. Note that SIGUSR1 can interfere with
2410 // SIGSEGV, see 4355769.
2411
2412 int os::sleep(Thread* thread, jlong millis, bool interruptible) {
2413 assert(thread == Thread::current(), "thread consistency check");
2414
2415 ParkEvent * const slp = thread->_SleepEvent ;
2416 slp->reset() ;
2417 OrderAccess::fence() ;
2418
2419 if (interruptible) {
2420 jlong prevtime = javaTimeNanos();
2421
2422 for (;;) {
2423 if (os::is_interrupted(thread, true)) {
2424 return OS_INTRPT;
2425 }
2426
2427 jlong newtime = javaTimeNanos();
2428
2429 if (newtime - prevtime < 0) {
2430 // time moving backwards, should only happen if no monotonic clock
2431 // not a guarantee() because JVM should not abort on kernel/glibc bugs
2432 assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
2433 } else {
2434 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
2435 }
2436
2437 if(millis <= 0) {
2438 return OS_OK;
2439 }
2440
2441 prevtime = newtime;
2442
2443 {
2444 assert(thread->is_Java_thread(), "sanity check");
2445 JavaThread *jt = (JavaThread *) thread;
2446 ThreadBlockInVM tbivm(jt);
2447 OSThreadWaitState osts(jt->osthread(), false /* not Object.wait() */);
2448
2449 jt->set_suspend_equivalent();
2450 // cleared by handle_special_suspend_equivalent_condition() or
2451 // java_suspend_self() via check_and_wait_while_suspended()
2452
2453 slp->park(millis);
2454
2455 // were we externally suspended while we were waiting?
2456 jt->check_and_wait_while_suspended();
2457 }
2458 }
2459 } else {
2460 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
2461 jlong prevtime = javaTimeNanos();
2462
2463 for (;;) {
2464 // It'd be nice to avoid the back-to-back javaTimeNanos() calls on
2465 // the 1st iteration ...
2466 jlong newtime = javaTimeNanos();
2467
2468 if (newtime - prevtime < 0) {
2469 // time moving backwards, should only happen if no monotonic clock
2470 // not a guarantee() because JVM should not abort on kernel/glibc bugs
2471 assert(!Bsd::supports_monotonic_clock(), "time moving backwards");
2472 } else {
2473 millis -= (newtime - prevtime) / NANOSECS_PER_MILLISEC;
2474 }
2475
2476 if(millis <= 0) break ;
2477
2478 prevtime = newtime;
2479 slp->park(millis);
2480 }
2481 return OS_OK ;
2482 }
2483 }
2484
2485 int os::naked_sleep() {
2486 // %% make the sleep time an integer flag. for now use 1 millisec.
2487 return os::sleep(Thread::current(), 1, false);
2488 }
2489
2490 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2491 void os::infinite_sleep() {
2492 while (true) { // sleep forever ...
2493 ::sleep(100); // ... 100 seconds at a time
2494 }
2495 }
2496
2497 // Used to convert frequent JVM_Yield() to nops
2498 bool os::dont_yield() {
2499 return DontYieldALot;
2500 }
2501
2502 void os::yield() {
2503 sched_yield();
2504 }
2505
2506 os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;}
2507
2508 void os::yield_all(int attempts) {
2509 // Yields to all threads, including threads with lower priorities
2510 // Threads on Bsd are all with same priority. The Solaris style
2511 // os::yield_all() with nanosleep(1ms) is not necessary.
2512 sched_yield();
2513 }
2514
2515 // Called from the tight loops to possibly influence time-sharing heuristics
2516 void os::loop_breaker(int attempts) {
2517 os::yield_all(attempts);
2518 }
2519
2520 ////////////////////////////////////////////////////////////////////////////////
2521 // thread priority support
2522
2523 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2524 // only supports dynamic priority, static priority must be zero. For real-time
2525 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
2526 // However, for large multi-threaded applications, SCHED_RR is not only slower
2527 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2528 // of 5 runs - Sep 2005).
2529 //
2530 // The following code actually changes the niceness of kernel-thread/LWP. It
2531 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
2532 // not the entire user process, and user level threads are 1:1 mapped to kernel
2533 // threads. It has always been the case, but could change in the future. For
2534 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2535 // It is only used when ThreadPriorityPolicy=1 and requires root privilege.
2536
2537 #if !defined(__APPLE__)
2538 int os::java_to_os_priority[CriticalPriority + 1] = {
2539 19, // 0 Entry should never be used
2540
2541 0, // 1 MinPriority
2542 3, // 2
2543 6, // 3
2544
2545 10, // 4
2546 15, // 5 NormPriority
2547 18, // 6
2548
2549 21, // 7
2550 25, // 8
2551 28, // 9 NearMaxPriority
2552
2553 31, // 10 MaxPriority
2554
2555 31 // 11 CriticalPriority
2556 };
2557 #else
2558 /* Using Mach high-level priority assignments */
2559 int os::java_to_os_priority[CriticalPriority + 1] = {
2560 0, // 0 Entry should never be used (MINPRI_USER)
2561
2562 27, // 1 MinPriority
2563 28, // 2
2564 29, // 3
2565
2566 30, // 4
2567 31, // 5 NormPriority (BASEPRI_DEFAULT)
2568 32, // 6
2569
2570 33, // 7
2571 34, // 8
2572 35, // 9 NearMaxPriority
2573
2574 36, // 10 MaxPriority
2575
2576 36 // 11 CriticalPriority
2577 };
2578 #endif
2579
2580 static int prio_init() {
2581 if (ThreadPriorityPolicy == 1) {
2582 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1
2583 // if effective uid is not root. Perhaps, a more elegant way of doing
2584 // this is to test CAP_SYS_NICE capability, but that will require libcap.so
2585 if (geteuid() != 0) {
2586 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
2587 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd");
2588 }
2589 ThreadPriorityPolicy = 0;
2590 }
2591 }
2592 if (UseCriticalJavaThreadPriority) {
2593 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2594 }
2595 return 0;
2596 }
2597
2598 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2599 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) return OS_OK;
2600
2601 #ifdef __OpenBSD__
2602 // OpenBSD pthread_setprio starves low priority threads
2603 return OS_OK;
2604 #elif defined(__FreeBSD__)
2605 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2606 #elif defined(__APPLE__) || defined(__NetBSD__)
2607 struct sched_param sp;
2608 int policy;
2609 pthread_t self = pthread_self();
2610
2611 if (pthread_getschedparam(self, &policy, &sp) != 0)
2612 return OS_ERR;
2613
2614 sp.sched_priority = newpri;
2615 if (pthread_setschedparam(self, policy, &sp) != 0)
2616 return OS_ERR;
2617
2618 return OS_OK;
2619 #else
2620 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2621 return (ret == 0) ? OS_OK : OS_ERR;
2622 #endif
2623 }
2624
2625 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2626 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) {
2627 *priority_ptr = java_to_os_priority[NormPriority];
2628 return OS_OK;
2629 }
2630
2631 errno = 0;
2632 #if defined(__OpenBSD__) || defined(__FreeBSD__)
2633 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2634 #elif defined(__APPLE__) || defined(__NetBSD__)
2635 int policy;
2636 struct sched_param sp;
2637
2638 pthread_getschedparam(pthread_self(), &policy, &sp);
2639 *priority_ptr = sp.sched_priority;
2640 #else
2641 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2642 #endif
2643 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2644 }
2645
2646 // Hint to the underlying OS that a task switch would not be good.
2647 // Void return because it's a hint and can fail.
2648 void os::hint_no_preempt() {}
2649
2650 ////////////////////////////////////////////////////////////////////////////////
2651 // suspend/resume support
2652
2653 // the low-level signal-based suspend/resume support is a remnant from the
2654 // old VM-suspension that used to be for java-suspension, safepoints etc,
2655 // within hotspot. Now there is a single use-case for this:
2656 // - calling get_thread_pc() on the VMThread by the flat-profiler task
2657 // that runs in the watcher thread.
2658 // The remaining code is greatly simplified from the more general suspension
2659 // code that used to be used.
2660 //
2661 // The protocol is quite simple:
2662 // - suspend:
2663 // - sends a signal to the target thread
2664 // - polls the suspend state of the osthread using a yield loop
2665 // - target thread signal handler (SR_handler) sets suspend state
2666 // and blocks in sigsuspend until continued
2667 // - resume:
2668 // - sets target osthread state to continue
2669 // - sends signal to end the sigsuspend loop in the SR_handler
2670 //
2671 // Note that the SR_lock plays no role in this suspend/resume protocol.
2672 //
2673
2674 static void resume_clear_context(OSThread *osthread) {
2675 osthread->set_ucontext(NULL);
2676 osthread->set_siginfo(NULL);
2677
2678 // notify the suspend action is completed, we have now resumed
2679 osthread->sr.clear_suspended();
2680 }
2681
2682 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2683 osthread->set_ucontext(context);
2684 osthread->set_siginfo(siginfo);
2685 }
2686
2687 //
2688 // Handler function invoked when a thread's execution is suspended or
2689 // resumed. We have to be careful that only async-safe functions are
2690 // called here (Note: most pthread functions are not async safe and
2691 // should be avoided.)
2692 //
2693 // Note: sigwait() is a more natural fit than sigsuspend() from an
2694 // interface point of view, but sigwait() prevents the signal hander
2695 // from being run. libpthread would get very confused by not having
2696 // its signal handlers run and prevents sigwait()'s use with the
2697 // mutex granting granting signal.
2698 //
2699 // Currently only ever called on the VMThread
2700 //
2701 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2702 // Save and restore errno to avoid confusing native code with EINTR
2703 // after sigsuspend.
2704 int old_errno = errno;
2705
2706 Thread* thread = Thread::current();
2707 OSThread* osthread = thread->osthread();
2708 assert(thread->is_VM_thread(), "Must be VMThread");
2709 // read current suspend action
2710 int action = osthread->sr.suspend_action();
2711 if (action == os::Bsd::SuspendResume::SR_SUSPEND) {
2712 suspend_save_context(osthread, siginfo, context);
2713
2714 // Notify the suspend action is about to be completed. do_suspend()
2715 // waits until SR_SUSPENDED is set and then returns. We will wait
2716 // here for a resume signal and that completes the suspend-other
2717 // action. do_suspend/do_resume is always called as a pair from
2718 // the same thread - so there are no races
2719
2720 // notify the caller
2721 osthread->sr.set_suspended();
2722
2723 sigset_t suspend_set; // signals for sigsuspend()
2724
2725 // get current set of blocked signals and unblock resume signal
2726 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2727 sigdelset(&suspend_set, SR_signum);
2728
2729 // wait here until we are resumed
2730 do {
2731 sigsuspend(&suspend_set);
2732 // ignore all returns until we get a resume signal
2733 } while (osthread->sr.suspend_action() != os::Bsd::SuspendResume::SR_CONTINUE);
2734
2735 resume_clear_context(osthread);
2736
2737 } else {
2738 assert(action == os::Bsd::SuspendResume::SR_CONTINUE, "unexpected sr action");
2739 // nothing special to do - just leave the handler
2740 }
2741
2742 errno = old_errno;
2743 }
2744
2745
2746 static int SR_initialize() {
2747 struct sigaction act;
2748 char *s;
2749 /* Get signal number to use for suspend/resume */
2750 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2751 int sig = ::strtol(s, 0, 10);
2752 if (sig > 0 || sig < NSIG) {
2753 SR_signum = sig;
2754 }
2755 }
2756
2757 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2758 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2759
2760 sigemptyset(&SR_sigset);
2761 sigaddset(&SR_sigset, SR_signum);
2762
2763 /* Set up signal handler for suspend/resume */
2764 act.sa_flags = SA_RESTART|SA_SIGINFO;
2765 act.sa_handler = (void (*)(int)) SR_handler;
2766
2767 // SR_signum is blocked by default.
2768 // 4528190 - We also need to block pthread restart signal (32 on all
2769 // supported Bsd platforms). Note that BsdThreads need to block
2770 // this signal for all threads to work properly. So we don't have
2771 // to use hard-coded signal number when setting up the mask.
2772 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2773
2774 if (sigaction(SR_signum, &act, 0) == -1) {
2775 return -1;
2776 }
2777
2778 // Save signal flag
2779 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2780 return 0;
2781 }
2782
2783 static int SR_finalize() {
2784 return 0;
2785 }
2786
2787
2788 // returns true on success and false on error - really an error is fatal
2789 // but this seems the normal response to library errors
2790 static bool do_suspend(OSThread* osthread) {
2791 // mark as suspended and send signal
2792 osthread->sr.set_suspend_action(os::Bsd::SuspendResume::SR_SUSPEND);
2793 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2794 assert_status(status == 0, status, "pthread_kill");
2795
2796 // check status and wait until notified of suspension
2797 if (status == 0) {
2798 for (int i = 0; !osthread->sr.is_suspended(); i++) {
2799 os::yield_all(i);
2800 }
2801 osthread->sr.set_suspend_action(os::Bsd::SuspendResume::SR_NONE);
2802 return true;
2803 }
2804 else {
2805 osthread->sr.set_suspend_action(os::Bsd::SuspendResume::SR_NONE);
2806 return false;
2807 }
2808 }
2809
2810 static void do_resume(OSThread* osthread) {
2811 assert(osthread->sr.is_suspended(), "thread should be suspended");
2812 osthread->sr.set_suspend_action(os::Bsd::SuspendResume::SR_CONTINUE);
2813
2814 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2815 assert_status(status == 0, status, "pthread_kill");
2816 // check status and wait unit notified of resumption
2817 if (status == 0) {
2818 for (int i = 0; osthread->sr.is_suspended(); i++) {
2819 os::yield_all(i);
2820 }
2821 }
2822 osthread->sr.set_suspend_action(os::Bsd::SuspendResume::SR_NONE);
2823 }
2824
2825 ////////////////////////////////////////////////////////////////////////////////
2826 // interrupt support
2827
2828 void os::interrupt(Thread* thread) {
2829 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
2830 "possibility of dangling Thread pointer");
2831
2832 OSThread* osthread = thread->osthread();
2833
2834 if (!osthread->interrupted()) {
2835 osthread->set_interrupted(true);
2836 // More than one thread can get here with the same value of osthread,
2837 // resulting in multiple notifications. We do, however, want the store
2838 // to interrupted() to be visible to other threads before we execute unpark().
2839 OrderAccess::fence();
2840 ParkEvent * const slp = thread->_SleepEvent ;
2841 if (slp != NULL) slp->unpark() ;
2842 }
2843
2844 // For JSR166. Unpark even if interrupt status already was set
2845 if (thread->is_Java_thread())
2846 ((JavaThread*)thread)->parker()->unpark();
2847
2848 ParkEvent * ev = thread->_ParkEvent ;
2849 if (ev != NULL) ev->unpark() ;
2850
2851 }
2852
2853 bool os::is_interrupted(Thread* thread, bool clear_interrupted) {
2854 assert(Thread::current() == thread || Threads_lock->owned_by_self(),
2855 "possibility of dangling Thread pointer");
2856
2857 OSThread* osthread = thread->osthread();
2858
2859 bool interrupted = osthread->interrupted();
2860
2861 if (interrupted && clear_interrupted) {
2862 osthread->set_interrupted(false);
2863 // consider thread->_SleepEvent->reset() ... optional optimization
2864 }
2865
2866 return interrupted;
2867 }
2868
2869 ///////////////////////////////////////////////////////////////////////////////////
2870 // signal handling (except suspend/resume)
2871
2872 // This routine may be used by user applications as a "hook" to catch signals.
2873 // The user-defined signal handler must pass unrecognized signals to this
2874 // routine, and if it returns true (non-zero), then the signal handler must
2875 // return immediately. If the flag "abort_if_unrecognized" is true, then this
2876 // routine will never retun false (zero), but instead will execute a VM panic
2877 // routine kill the process.
2878 //
2879 // If this routine returns false, it is OK to call it again. This allows
2880 // the user-defined signal handler to perform checks either before or after
2881 // the VM performs its own checks. Naturally, the user code would be making
2882 // a serious error if it tried to handle an exception (such as a null check
2883 // or breakpoint) that the VM was generating for its own correct operation.
2884 //
2885 // This routine may recognize any of the following kinds of signals:
2886 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
2887 // It should be consulted by handlers for any of those signals.
2888 //
2889 // The caller of this routine must pass in the three arguments supplied
2890 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
2891 // field of the structure passed to sigaction(). This routine assumes that
2892 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
2893 //
2894 // Note that the VM will print warnings if it detects conflicting signal
2895 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
2896 //
2897 extern "C" JNIEXPORT int
2898 JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
2899 void* ucontext, int abort_if_unrecognized);
2900
2901 void signalHandler(int sig, siginfo_t* info, void* uc) {
2902 assert(info != NULL && uc != NULL, "it must be old kernel");
2903 int orig_errno = errno; // Preserve errno value over signal handler.
2904 JVM_handle_bsd_signal(sig, info, uc, true);
2905 errno = orig_errno;
2906 }
2907
2908
2909 // This boolean allows users to forward their own non-matching signals
2910 // to JVM_handle_bsd_signal, harmlessly.
2911 bool os::Bsd::signal_handlers_are_installed = false;
2912
2913 // For signal-chaining
2914 struct sigaction os::Bsd::sigact[MAXSIGNUM];
2915 unsigned int os::Bsd::sigs = 0;
2916 bool os::Bsd::libjsig_is_loaded = false;
2917 typedef struct sigaction *(*get_signal_t)(int);
2918 get_signal_t os::Bsd::get_signal_action = NULL;
2919
2920 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
2921 struct sigaction *actp = NULL;
2922
2923 if (libjsig_is_loaded) {
2924 // Retrieve the old signal handler from libjsig
2925 actp = (*get_signal_action)(sig);
2926 }
2927 if (actp == NULL) {
2928 // Retrieve the preinstalled signal handler from jvm
2929 actp = get_preinstalled_handler(sig);
2930 }
2931
2932 return actp;
2933 }
2934
2935 static bool call_chained_handler(struct sigaction *actp, int sig,
2936 siginfo_t *siginfo, void *context) {
2937 // Call the old signal handler
2938 if (actp->sa_handler == SIG_DFL) {
2939 // It's more reasonable to let jvm treat it as an unexpected exception
2940 // instead of taking the default action.
2941 return false;
2942 } else if (actp->sa_handler != SIG_IGN) {
2943 if ((actp->sa_flags & SA_NODEFER) == 0) {
2944 // automaticlly block the signal
2945 sigaddset(&(actp->sa_mask), sig);
2946 }
2947
2948 sa_handler_t hand;
2949 sa_sigaction_t sa;
2950 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
2951 // retrieve the chained handler
2952 if (siginfo_flag_set) {
2953 sa = actp->sa_sigaction;
2954 } else {
2955 hand = actp->sa_handler;
2956 }
2957
2958 if ((actp->sa_flags & SA_RESETHAND) != 0) {
2959 actp->sa_handler = SIG_DFL;
2960 }
2961
2962 // try to honor the signal mask
2963 sigset_t oset;
2964 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
2965
2966 // call into the chained handler
2967 if (siginfo_flag_set) {
2968 (*sa)(sig, siginfo, context);
2969 } else {
2970 (*hand)(sig);
2971 }
2972
2973 // restore the signal mask
2974 pthread_sigmask(SIG_SETMASK, &oset, 0);
2975 }
2976 // Tell jvm's signal handler the signal is taken care of.
2977 return true;
2978 }
2979
2980 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
2981 bool chained = false;
2982 // signal-chaining
2983 if (UseSignalChaining) {
2984 struct sigaction *actp = get_chained_signal_action(sig);
2985 if (actp != NULL) {
2986 chained = call_chained_handler(actp, sig, siginfo, context);
2987 }
2988 }
2989 return chained;
2990 }
2991
2992 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) {
2993 if ((( (unsigned int)1 << sig ) & sigs) != 0) {
2994 return &sigact[sig];
2995 }
2996 return NULL;
2997 }
2998
2999 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
3000 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3001 sigact[sig] = oldAct;
3002 sigs |= (unsigned int)1 << sig;
3003 }
3004
3005 // for diagnostic
3006 int os::Bsd::sigflags[MAXSIGNUM];
3007
3008 int os::Bsd::get_our_sigflags(int sig) {
3009 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3010 return sigflags[sig];
3011 }
3012
3013 void os::Bsd::set_our_sigflags(int sig, int flags) {
3014 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3015 sigflags[sig] = flags;
3016 }
3017
3018 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
3019 // Check for overwrite.
3020 struct sigaction oldAct;
3021 sigaction(sig, (struct sigaction*)NULL, &oldAct);
3022
3023 void* oldhand = oldAct.sa_sigaction
3024 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3025 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3026 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
3027 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
3028 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
3029 if (AllowUserSignalHandlers || !set_installed) {
3030 // Do not overwrite; user takes responsibility to forward to us.
3031 return;
3032 } else if (UseSignalChaining) {
3033 // save the old handler in jvm
3034 save_preinstalled_handler(sig, oldAct);
3035 // libjsig also interposes the sigaction() call below and saves the
3036 // old sigaction on it own.
3037 } else {
3038 fatal(err_msg("Encountered unexpected pre-existing sigaction handler "
3039 "%#lx for signal %d.", (long)oldhand, sig));
3040 }
3041 }
3042
3043 struct sigaction sigAct;
3044 sigfillset(&(sigAct.sa_mask));
3045 sigAct.sa_handler = SIG_DFL;
3046 if (!set_installed) {
3047 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3048 } else {
3049 sigAct.sa_sigaction = signalHandler;
3050 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3051 }
3052 // Save flags, which are set by ours
3053 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3054 sigflags[sig] = sigAct.sa_flags;
3055
3056 int ret = sigaction(sig, &sigAct, &oldAct);
3057 assert(ret == 0, "check");
3058
3059 void* oldhand2 = oldAct.sa_sigaction
3060 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3061 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3062 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
3063 }
3064
3065 // install signal handlers for signals that HotSpot needs to
3066 // handle in order to support Java-level exception handling.
3067
3068 void os::Bsd::install_signal_handlers() {
3069 if (!signal_handlers_are_installed) {
3070 signal_handlers_are_installed = true;
3071
3072 // signal-chaining
3073 typedef void (*signal_setting_t)();
3074 signal_setting_t begin_signal_setting = NULL;
3075 signal_setting_t end_signal_setting = NULL;
3076 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3077 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
3078 if (begin_signal_setting != NULL) {
3079 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3080 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
3081 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
3082 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
3083 libjsig_is_loaded = true;
3084 assert(UseSignalChaining, "should enable signal-chaining");
3085 }
3086 if (libjsig_is_loaded) {
3087 // Tell libjsig jvm is setting signal handlers
3088 (*begin_signal_setting)();
3089 }
3090
3091 set_signal_handler(SIGSEGV, true);
3092 set_signal_handler(SIGPIPE, true);
3093 set_signal_handler(SIGBUS, true);
3094 set_signal_handler(SIGILL, true);
3095 set_signal_handler(SIGFPE, true);
3096 set_signal_handler(SIGXFSZ, true);
3097
3098 #if defined(__APPLE__)
3099 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
3100 // signals caught and handled by the JVM. To work around this, we reset the mach task
3101 // signal handler that's placed on our process by CrashReporter. This disables
3102 // CrashReporter-based reporting.
3103 //
3104 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
3105 // on caught fatal signals.
3106 //
3107 // Additionally, gdb installs both standard BSD signal handlers, and mach exception
3108 // handlers. By replacing the existing task exception handler, we disable gdb's mach
3109 // exception handling, while leaving the standard BSD signal handlers functional.
3110 kern_return_t kr;
3111 kr = task_set_exception_ports(mach_task_self(),
3112 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
3113 MACH_PORT_NULL,
3114 EXCEPTION_STATE_IDENTITY,
3115 MACHINE_THREAD_STATE);
3116
3117 assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
3118 #endif
3119
3120 if (libjsig_is_loaded) {
3121 // Tell libjsig jvm finishes setting signal handlers
3122 (*end_signal_setting)();
3123 }
3124
3125 // We don't activate signal checker if libjsig is in place, we trust ourselves
3126 // and if UserSignalHandler is installed all bets are off
3127 if (CheckJNICalls) {
3128 if (libjsig_is_loaded) {
3129 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
3130 check_signals = false;
3131 }
3132 if (AllowUserSignalHandlers) {
3133 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
3134 check_signals = false;
3135 }
3136 }
3137 }
3138 }
3139
3140
3141 /////
3142 // glibc on Bsd platform uses non-documented flag
3143 // to indicate, that some special sort of signal
3144 // trampoline is used.
3145 // We will never set this flag, and we should
3146 // ignore this flag in our diagnostic
3147 #ifdef SIGNIFICANT_SIGNAL_MASK
3148 #undef SIGNIFICANT_SIGNAL_MASK
3149 #endif
3150 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
3151
3152 static const char* get_signal_handler_name(address handler,
3153 char* buf, int buflen) {
3154 int offset;
3155 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
3156 if (found) {
3157 // skip directory names
3158 const char *p1, *p2;
3159 p1 = buf;
3160 size_t len = strlen(os::file_separator());
3161 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
3162 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
3163 } else {
3164 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
3165 }
3166 return buf;
3167 }
3168
3169 static void print_signal_handler(outputStream* st, int sig,
3170 char* buf, size_t buflen) {
3171 struct sigaction sa;
3172
3173 sigaction(sig, NULL, &sa);
3174
3175 // See comment for SIGNIFICANT_SIGNAL_MASK define
3176 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3177
3178 st->print("%s: ", os::exception_name(sig, buf, buflen));
3179
3180 address handler = (sa.sa_flags & SA_SIGINFO)
3181 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
3182 : CAST_FROM_FN_PTR(address, sa.sa_handler);
3183
3184 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
3185 st->print("SIG_DFL");
3186 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
3187 st->print("SIG_IGN");
3188 } else {
3189 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
3190 }
3191
3192 st->print(", sa_mask[0]=" PTR32_FORMAT, *(uint32_t*)&sa.sa_mask);
3193
3194 address rh = VMError::get_resetted_sighandler(sig);
3195 // May be, handler was resetted by VMError?
3196 if(rh != NULL) {
3197 handler = rh;
3198 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
3199 }
3200
3201 st->print(", sa_flags=" PTR32_FORMAT, sa.sa_flags);
3202
3203 // Check: is it our handler?
3204 if(handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
3205 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
3206 // It is our signal handler
3207 // check for flags, reset system-used one!
3208 if((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3209 st->print(
3210 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
3211 os::Bsd::get_our_sigflags(sig));
3212 }
3213 }
3214 st->cr();
3215 }
3216
3217
3218 #define DO_SIGNAL_CHECK(sig) \
3219 if (!sigismember(&check_signal_done, sig)) \
3220 os::Bsd::check_signal_handler(sig)
3221
3222 // This method is a periodic task to check for misbehaving JNI applications
3223 // under CheckJNI, we can add any periodic checks here
3224
3225 void os::run_periodic_checks() {
3226
3227 if (check_signals == false) return;
3228
3229 // SEGV and BUS if overridden could potentially prevent
3230 // generation of hs*.log in the event of a crash, debugging
3231 // such a case can be very challenging, so we absolutely
3232 // check the following for a good measure:
3233 DO_SIGNAL_CHECK(SIGSEGV);
3234 DO_SIGNAL_CHECK(SIGILL);
3235 DO_SIGNAL_CHECK(SIGFPE);
3236 DO_SIGNAL_CHECK(SIGBUS);
3237 DO_SIGNAL_CHECK(SIGPIPE);
3238 DO_SIGNAL_CHECK(SIGXFSZ);
3239
3240
3241 // ReduceSignalUsage allows the user to override these handlers
3242 // see comments at the very top and jvm_solaris.h
3243 if (!ReduceSignalUsage) {
3244 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
3245 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
3246 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
3247 DO_SIGNAL_CHECK(BREAK_SIGNAL);
3248 }
3249
3250 DO_SIGNAL_CHECK(SR_signum);
3251 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL);
3252 }
3253
3254 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
3255
3256 static os_sigaction_t os_sigaction = NULL;
3257
3258 void os::Bsd::check_signal_handler(int sig) {
3259 char buf[O_BUFLEN];
3260 address jvmHandler = NULL;
3261
3262
3263 struct sigaction act;
3264 if (os_sigaction == NULL) {
3265 // only trust the default sigaction, in case it has been interposed
3266 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
3267 if (os_sigaction == NULL) return;
3268 }
3269
3270 os_sigaction(sig, (struct sigaction*)NULL, &act);
3271
3272
3273 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3274
3275 address thisHandler = (act.sa_flags & SA_SIGINFO)
3276 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3277 : CAST_FROM_FN_PTR(address, act.sa_handler) ;
3278
3279
3280 switch(sig) {
3281 case SIGSEGV:
3282 case SIGBUS:
3283 case SIGFPE:
3284 case SIGPIPE:
3285 case SIGILL:
3286 case SIGXFSZ:
3287 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
3288 break;
3289
3290 case SHUTDOWN1_SIGNAL:
3291 case SHUTDOWN2_SIGNAL:
3292 case SHUTDOWN3_SIGNAL:
3293 case BREAK_SIGNAL:
3294 jvmHandler = (address)user_handler();
3295 break;
3296
3297 case INTERRUPT_SIGNAL:
3298 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL);
3299 break;
3300
3301 default:
3302 if (sig == SR_signum) {
3303 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3304 } else {
3305 return;
3306 }
3307 break;
3308 }
3309
3310 if (thisHandler != jvmHandler) {
3311 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3312 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3313 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3314 // No need to check this sig any longer
3315 sigaddset(&check_signal_done, sig);
3316 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3317 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3318 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig));
3319 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags);
3320 // No need to check this sig any longer
3321 sigaddset(&check_signal_done, sig);
3322 }
3323
3324 // Dump all the signal
3325 if (sigismember(&check_signal_done, sig)) {
3326 print_signal_handlers(tty, buf, O_BUFLEN);
3327 }
3328 }
3329
3330 extern void report_error(char* file_name, int line_no, char* title, char* format, ...);
3331
3332 extern bool signal_name(int signo, char* buf, size_t len);
3333
3334 const char* os::exception_name(int exception_code, char* buf, size_t size) {
3335 if (0 < exception_code && exception_code <= SIGRTMAX) {
3336 // signal
3337 if (!signal_name(exception_code, buf, size)) {
3338 jio_snprintf(buf, size, "SIG%d", exception_code);
3339 }
3340 return buf;
3341 } else {
3342 return NULL;
3343 }
3344 }
3345
3346 // this is called _before_ the most of global arguments have been parsed
3347 void os::init(void) {
3348 char dummy; /* used to get a guess on initial stack address */
3349 // first_hrtime = gethrtime();
3350
3351 // With BsdThreads the JavaMain thread pid (primordial thread)
3352 // is different than the pid of the java launcher thread.
3353 // So, on Bsd, the launcher thread pid is passed to the VM
3354 // via the sun.java.launcher.pid property.
3355 // Use this property instead of getpid() if it was correctly passed.
3356 // See bug 6351349.
3357 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid();
3358
3359 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid();
3360
3361 clock_tics_per_sec = CLK_TCK;
3362
3363 init_random(1234567);
3364
3365 ThreadCritical::initialize();
3366
3367 Bsd::set_page_size(getpagesize());
3368 if (Bsd::page_size() == -1) {
3369 fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)",
3370 strerror(errno)));
3371 }
3372 init_page_sizes((size_t) Bsd::page_size());
3373
3374 Bsd::initialize_system_info();
3375
3376 // main_thread points to the aboriginal thread
3377 Bsd::_main_thread = pthread_self();
3378
3379 Bsd::clock_init();
3380 initial_time_count = os::elapsed_counter();
3381
3382 #ifdef __APPLE__
3383 // XXXDARWIN
3384 // Work around the unaligned VM callbacks in hotspot's
3385 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on
3386 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces
3387 // alignment when doing symbol lookup. To work around this, we force early
3388 // binding of all symbols now, thus binding when alignment is known-good.
3389 _dyld_bind_fully_image_containing_address((const void *) &os::init);
3390 #endif
3391 }
3392
3393 // To install functions for atexit system call
3394 extern "C" {
3395 static void perfMemory_exit_helper() {
3396 perfMemory_exit();
3397 }
3398 }
3399
3400 // this is called _after_ the global arguments have been parsed
3401 jint os::init_2(void)
3402 {
3403 // Allocate a single page and mark it as readable for safepoint polling
3404 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3405 guarantee( polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page" );
3406
3407 os::set_polling_page( polling_page );
3408
3409 #ifndef PRODUCT
3410 if(Verbose && PrintMiscellaneous)
3411 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page);
3412 #endif
3413
3414 if (!UseMembar) {
3415 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3416 guarantee( mem_serialize_page != NULL, "mmap Failed for memory serialize page");
3417 os::set_memory_serialize_page( mem_serialize_page );
3418
3419 #ifndef PRODUCT
3420 if(Verbose && PrintMiscellaneous)
3421 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page);
3422 #endif
3423 }
3424
3425 os::large_page_init();
3426
3427 // initialize suspend/resume support - must do this before signal_sets_init()
3428 if (SR_initialize() != 0) {
3429 perror("SR_initialize failed");
3430 return JNI_ERR;
3431 }
3432
3433 Bsd::signal_sets_init();
3434 Bsd::install_signal_handlers();
3435
3436 // Check minimum allowable stack size for thread creation and to initialize
3437 // the java system classes, including StackOverflowError - depends on page
3438 // size. Add a page for compiler2 recursion in main thread.
3439 // Add in 2*BytesPerWord times page size to account for VM stack during
3440 // class initialization depending on 32 or 64 bit VM.
3441 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed,
3442 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+
3443 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size());
3444
3445 size_t threadStackSizeInBytes = ThreadStackSize * K;
3446 if (threadStackSizeInBytes != 0 &&
3447 threadStackSizeInBytes < os::Bsd::min_stack_allowed) {
3448 tty->print_cr("\nThe stack size specified is too small, "
3449 "Specify at least %dk",
3450 os::Bsd::min_stack_allowed/ K);
3451 return JNI_ERR;
3452 }
3453
3454 // Make the stack size a multiple of the page size so that
3455 // the yellow/red zones can be guarded.
3456 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes,
3457 vm_page_size()));
3458
3459 if (MaxFDLimit) {
3460 // set the number of file descriptors to max. print out error
3461 // if getrlimit/setrlimit fails but continue regardless.
3462 struct rlimit nbr_files;
3463 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3464 if (status != 0) {
3465 if (PrintMiscellaneous && (Verbose || WizardMode))
3466 perror("os::init_2 getrlimit failed");
3467 } else {
3468 nbr_files.rlim_cur = nbr_files.rlim_max;
3469
3470 #ifdef __APPLE__
3471 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3472 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3473 // be used instead
3474 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3475 #endif
3476
3477 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3478 if (status != 0) {
3479 if (PrintMiscellaneous && (Verbose || WizardMode))
3480 perror("os::init_2 setrlimit failed");
3481 }
3482 }
3483 }
3484
3485 // at-exit methods are called in the reverse order of their registration.
3486 // atexit functions are called on return from main or as a result of a
3487 // call to exit(3C). There can be only 32 of these functions registered
3488 // and atexit() does not set errno.
3489
3490 if (PerfAllowAtExitRegistration) {
3491 // only register atexit functions if PerfAllowAtExitRegistration is set.
3492 // atexit functions can be delayed until process exit time, which
3493 // can be problematic for embedded VM situations. Embedded VMs should
3494 // call DestroyJavaVM() to assure that VM resources are released.
3495
3496 // note: perfMemory_exit_helper atexit function may be removed in
3497 // the future if the appropriate cleanup code can be added to the
3498 // VM_Exit VMOperation's doit method.
3499 if (atexit(perfMemory_exit_helper) != 0) {
3500 warning("os::init2 atexit(perfMemory_exit_helper) failed");
3501 }
3502 }
3503
3504 // initialize thread priority policy
3505 prio_init();
3506
3507 #ifdef __APPLE__
3508 // dynamically link to objective c gc registration
3509 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3510 if (handleLibObjc != NULL) {
3511 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3512 }
3513 #endif
3514
3515 return JNI_OK;
3516 }
3517
3518 // this is called at the end of vm_initialization
3519 void os::init_3(void) { }
3520
3521 // Mark the polling page as unreadable
3522 void os::make_polling_page_unreadable(void) {
3523 if( !guard_memory((char*)_polling_page, Bsd::page_size()) )
3524 fatal("Could not disable polling page");
3525 };
3526
3527 // Mark the polling page as readable
3528 void os::make_polling_page_readable(void) {
3529 if( !bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
3530 fatal("Could not enable polling page");
3531 }
3532 };
3533
3534 int os::active_processor_count() {
3535 return _processor_count;
3536 }
3537
3538 void os::set_native_thread_name(const char *name) {
3539 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3540 // This is only supported in Snow Leopard and beyond
3541 if (name != NULL) {
3542 // Add a "Java: " prefix to the name
3543 char buf[MAXTHREADNAMESIZE];
3544 snprintf(buf, sizeof(buf), "Java: %s", name);
3545 pthread_setname_np(buf);
3546 }
3547 #endif
3548 }
3549
3550 bool os::distribute_processes(uint length, uint* distribution) {
3551 // Not yet implemented.
3552 return false;
3553 }
3554
3555 bool os::bind_to_processor(uint processor_id) {
3556 // Not yet implemented.
3557 return false;
3558 }
3559
3560 ///
3561
3562 // Suspends the target using the signal mechanism and then grabs the PC before
3563 // resuming the target. Used by the flat-profiler only
3564 ExtendedPC os::get_thread_pc(Thread* thread) {
3565 // Make sure that it is called by the watcher for the VMThread
3566 assert(Thread::current()->is_Watcher_thread(), "Must be watcher");
3567 assert(thread->is_VM_thread(), "Can only be called for VMThread");
3568
3569 ExtendedPC epc;
3570
3571 OSThread* osthread = thread->osthread();
3572 if (do_suspend(osthread)) {
3573 if (osthread->ucontext() != NULL) {
3574 epc = os::Bsd::ucontext_get_pc(osthread->ucontext());
3575 } else {
3576 // NULL context is unexpected, double-check this is the VMThread
3577 guarantee(thread->is_VM_thread(), "can only be called for VMThread");
3578 }
3579 do_resume(osthread);
3580 }
3581 // failure means pthread_kill failed for some reason - arguably this is
3582 // a fatal problem, but such problems are ignored elsewhere
3583
3584 return epc;
3585 }
3586
3587 int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime)
3588 {
3589 return pthread_cond_timedwait(_cond, _mutex, _abstime);
3590 }
3591
3592 ////////////////////////////////////////////////////////////////////////////////
3593 // debug support
3594
3595 static address same_page(address x, address y) {
3596 int page_bits = -os::vm_page_size();
3597 if ((intptr_t(x) & page_bits) == (intptr_t(y) & page_bits))
3598 return x;
3599 else if (x > y)
3600 return (address)(intptr_t(y) | ~page_bits) + 1;
3601 else
3602 return (address)(intptr_t(y) & page_bits);
3603 }
3604
3605 bool os::find(address addr, outputStream* st) {
3606 Dl_info dlinfo;
3607 memset(&dlinfo, 0, sizeof(dlinfo));
3608 if (dladdr(addr, &dlinfo)) {
3609 st->print(PTR_FORMAT ": ", addr);
3610 if (dlinfo.dli_sname != NULL) {
3611 st->print("%s+%#x", dlinfo.dli_sname,
3612 addr - (intptr_t)dlinfo.dli_saddr);
3613 } else if (dlinfo.dli_fname) {
3614 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase);
3615 } else {
3616 st->print("<absolute address>");
3617 }
3618 if (dlinfo.dli_fname) {
3619 st->print(" in %s", dlinfo.dli_fname);
3620 }
3621 if (dlinfo.dli_fbase) {
3622 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase);
3623 }
3624 st->cr();
3625
3626 if (Verbose) {
3627 // decode some bytes around the PC
3628 address begin = same_page(addr-40, addr);
3629 address end = same_page(addr+40, addr);
3630 address lowest = (address) dlinfo.dli_sname;
3631 if (!lowest) lowest = (address) dlinfo.dli_fbase;
3632 if (begin < lowest) begin = lowest;
3633 Dl_info dlinfo2;
3634 if (dladdr(end, &dlinfo2) && dlinfo2.dli_saddr != dlinfo.dli_saddr
3635 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin)
3636 end = (address) dlinfo2.dli_saddr;
3637 Disassembler::decode(begin, end, st);
3638 }
3639 return true;
3640 }
3641 return false;
3642 }
3643
3644 ////////////////////////////////////////////////////////////////////////////////
3645 // misc
3646
3647 // This does not do anything on Bsd. This is basically a hook for being
3648 // able to use structured exception handling (thread-local exception filters)
3649 // on, e.g., Win32.
3650 void
3651 os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method,
3652 JavaCallArguments* args, Thread* thread) {
3653 f(value, method, args, thread);
3654 }
3655
3656 void os::print_statistics() {
3657 }
3658
3659 int os::message_box(const char* title, const char* message) {
3660 int i;
3661 fdStream err(defaultStream::error_fd());
3662 for (i = 0; i < 78; i++) err.print_raw("=");
3663 err.cr();
3664 err.print_raw_cr(title);
3665 for (i = 0; i < 78; i++) err.print_raw("-");
3666 err.cr();
3667 err.print_raw_cr(message);
3668 for (i = 0; i < 78; i++) err.print_raw("=");
3669 err.cr();
3670
3671 char buf[16];
3672 // Prevent process from exiting upon "read error" without consuming all CPU
3673 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3674
3675 return buf[0] == 'y' || buf[0] == 'Y';
3676 }
3677
3678 int os::stat(const char *path, struct stat *sbuf) {
3679 char pathbuf[MAX_PATH];
3680 if (strlen(path) > MAX_PATH - 1) {
3681 errno = ENAMETOOLONG;
3682 return -1;
3683 }
3684 os::native_path(strcpy(pathbuf, path));
3685 return ::stat(pathbuf, sbuf);
3686 }
3687
3688 bool os::check_heap(bool force) {
3689 return true;
3690 }
3691
3692 int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) {
3693 return ::vsnprintf(buf, count, format, args);
3694 }
3695
3696 // Is a (classpath) directory empty?
3697 bool os::dir_is_empty(const char* path) {
3698 DIR *dir = NULL;
3699 struct dirent *ptr;
3700
3701 dir = opendir(path);
3702 if (dir == NULL) return true;
3703
3704 /* Scan the directory */
3705 bool result = true;
3706 char buf[sizeof(struct dirent) + MAX_PATH];
3707 while (result && (ptr = ::readdir(dir)) != NULL) {
3708 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3709 result = false;
3710 }
3711 }
3712 closedir(dir);
3713 return result;
3714 }
3715
3716 // This code originates from JDK's sysOpen and open64_w
3717 // from src/solaris/hpi/src/system_md.c
3718
3719 #ifndef O_DELETE
3720 #define O_DELETE 0x10000
3721 #endif
3722
3723 // Open a file. Unlink the file immediately after open returns
3724 // if the specified oflag has the O_DELETE flag set.
3725 // O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c
3726
3727 int os::open(const char *path, int oflag, int mode) {
3728
3729 if (strlen(path) > MAX_PATH - 1) {
3730 errno = ENAMETOOLONG;
3731 return -1;
3732 }
3733 int fd;
3734 int o_delete = (oflag & O_DELETE);
3735 oflag = oflag & ~O_DELETE;
3736
3737 fd = ::open(path, oflag, mode);
3738 if (fd == -1) return -1;
3739
3740 //If the open succeeded, the file might still be a directory
3741 {
3742 struct stat buf;
3743 int ret = ::fstat(fd, &buf);
3744 int st_mode = buf.st_mode;
3745
3746 if (ret != -1) {
3747 if ((st_mode & S_IFMT) == S_IFDIR) {
3748 errno = EISDIR;
3749 ::close(fd);
3750 return -1;
3751 }
3752 } else {
3753 ::close(fd);
3754 return -1;
3755 }
3756 }
3757
3758 /*
3759 * All file descriptors that are opened in the JVM and not
3760 * specifically destined for a subprocess should have the
3761 * close-on-exec flag set. If we don't set it, then careless 3rd
3762 * party native code might fork and exec without closing all
3763 * appropriate file descriptors (e.g. as we do in closeDescriptors in
3764 * UNIXProcess.c), and this in turn might:
3765 *
3766 * - cause end-of-file to fail to be detected on some file
3767 * descriptors, resulting in mysterious hangs, or
3768 *
3769 * - might cause an fopen in the subprocess to fail on a system
3770 * suffering from bug 1085341.
3771 *
3772 * (Yes, the default setting of the close-on-exec flag is a Unix
3773 * design flaw)
3774 *
3775 * See:
3776 * 1085341: 32-bit stdio routines should support file descriptors >255
3777 * 4843136: (process) pipe file descriptor from Runtime.exec not being closed
3778 * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
3779 */
3780 #ifdef FD_CLOEXEC
3781 {
3782 int flags = ::fcntl(fd, F_GETFD);
3783 if (flags != -1)
3784 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
3785 }
3786 #endif
3787
3788 if (o_delete != 0) {
3789 ::unlink(path);
3790 }
3791 return fd;
3792 }
3793
3794
3795 // create binary file, rewriting existing file if required
3796 int os::create_binary_file(const char* path, bool rewrite_existing) {
3797 int oflags = O_WRONLY | O_CREAT;
3798 if (!rewrite_existing) {
3799 oflags |= O_EXCL;
3800 }
3801 return ::open(path, oflags, S_IREAD | S_IWRITE);
3802 }
3803
3804 // return current position of file pointer
3805 jlong os::current_file_offset(int fd) {
3806 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
3807 }
3808
3809 // move file pointer to the specified offset
3810 jlong os::seek_to_file_offset(int fd, jlong offset) {
3811 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
3812 }
3813
3814 // This code originates from JDK's sysAvailable
3815 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
3816
3817 int os::available(int fd, jlong *bytes) {
3818 jlong cur, end;
3819 int mode;
3820 struct stat buf;
3821
3822 if (::fstat(fd, &buf) >= 0) {
3823 mode = buf.st_mode;
3824 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
3825 /*
3826 * XXX: is the following call interruptible? If so, this might
3827 * need to go through the INTERRUPT_IO() wrapper as for other
3828 * blocking, interruptible calls in this file.
3829 */
3830 int n;
3831 if (::ioctl(fd, FIONREAD, &n) >= 0) {
3832 *bytes = n;
3833 return 1;
3834 }
3835 }
3836 }
3837 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
3838 return 0;
3839 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
3840 return 0;
3841 } else if (::lseek(fd, cur, SEEK_SET) == -1) {
3842 return 0;
3843 }
3844 *bytes = end - cur;
3845 return 1;
3846 }
3847
3848 int os::socket_available(int fd, jint *pbytes) {
3849 if (fd < 0)
3850 return OS_OK;
3851
3852 int ret;
3853
3854 RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret);
3855
3856 //%% note ioctl can return 0 when successful, JVM_SocketAvailable
3857 // is expected to return 0 on failure and 1 on success to the jdk.
3858
3859 return (ret == OS_ERR) ? 0 : 1;
3860 }
3861
3862 // Map a block of memory.
3863 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
3864 char *addr, size_t bytes, bool read_only,
3865 bool allow_exec) {
3866 int prot;
3867 int flags;
3868
3869 if (read_only) {
3870 prot = PROT_READ;
3871 flags = MAP_SHARED;
3872 } else {
3873 prot = PROT_READ | PROT_WRITE;
3874 flags = MAP_PRIVATE;
3875 }
3876
3877 if (allow_exec) {
3878 prot |= PROT_EXEC;
3879 }
3880
3881 if (addr != NULL) {
3882 flags |= MAP_FIXED;
3883 }
3884
3885 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
3886 fd, file_offset);
3887 if (mapped_address == MAP_FAILED) {
3888 return NULL;
3889 }
3890 return mapped_address;
3891 }
3892
3893
3894 // Remap a block of memory.
3895 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
3896 char *addr, size_t bytes, bool read_only,
3897 bool allow_exec) {
3898 // same as map_memory() on this OS
3899 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
3900 allow_exec);
3901 }
3902
3903
3904 // Unmap a block of memory.
3905 bool os::pd_unmap_memory(char* addr, size_t bytes) {
3906 return munmap(addr, bytes) == 0;
3907 }
3908
3909 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
3910 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
3911 // of a thread.
3912 //
3913 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
3914 // the fast estimate available on the platform.
3915
3916 jlong os::current_thread_cpu_time() {
3917 #ifdef __APPLE__
3918 return os::thread_cpu_time(Thread::current(), true /* user + sys */);
3919 #else
3920 Unimplemented();
3921 return 0;
3922 #endif
3923 }
3924
3925 jlong os::thread_cpu_time(Thread* thread) {
3926 #ifdef __APPLE__
3927 return os::thread_cpu_time(thread, true /* user + sys */);
3928 #else
3929 Unimplemented();
3930 return 0;
3931 #endif
3932 }
3933
3934 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
3935 #ifdef __APPLE__
3936 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
3937 #else
3938 Unimplemented();
3939 return 0;
3940 #endif
3941 }
3942
3943 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
3944 #ifdef __APPLE__
3945 struct thread_basic_info tinfo;
3946 mach_msg_type_number_t tcount = THREAD_INFO_MAX;
3947 kern_return_t kr;
3948 thread_t mach_thread;
3949
3950 mach_thread = thread->osthread()->thread_id();
3951 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
3952 if (kr != KERN_SUCCESS)
3953 return -1;
3954
3955 if (user_sys_cpu_time) {
3956 jlong nanos;
3957 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
3958 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
3959 return nanos;
3960 } else {
3961 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
3962 }
3963 #else
3964 Unimplemented();
3965 return 0;
3966 #endif
3967 }
3968
3969
3970 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
3971 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
3972 info_ptr->may_skip_backward = false; // elapsed time not wall time
3973 info_ptr->may_skip_forward = false; // elapsed time not wall time
3974 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
3975 }
3976
3977 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
3978 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
3979 info_ptr->may_skip_backward = false; // elapsed time not wall time
3980 info_ptr->may_skip_forward = false; // elapsed time not wall time
3981 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
3982 }
3983
3984 bool os::is_thread_cpu_time_supported() {
3985 #ifdef __APPLE__
3986 return true;
3987 #else
3988 return false;
3989 #endif
3990 }
3991
3992 // System loadavg support. Returns -1 if load average cannot be obtained.
3993 // Bsd doesn't yet have a (official) notion of processor sets,
3994 // so just return the system wide load average.
3995 int os::loadavg(double loadavg[], int nelem) {
3996 return ::getloadavg(loadavg, nelem);
3997 }
3998
3999 void os::pause() {
4000 char filename[MAX_PATH];
4001 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
4002 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
4003 } else {
4004 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
4005 }
4006
4007 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
4008 if (fd != -1) {
4009 struct stat buf;
4010 ::close(fd);
4011 while (::stat(filename, &buf) == 0) {
4012 (void)::poll(NULL, 0, 100);
4013 }
4014 } else {
4015 jio_fprintf(stderr,
4016 "Could not open pause file '%s', continuing immediately.\n", filename);
4017 }
4018 }
4019
4020
4021 // Refer to the comments in os_solaris.cpp park-unpark.
4022 //
4023 // Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can
4024 // hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable.
4025 // For specifics regarding the bug see GLIBC BUGID 261237 :
4026 // http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html.
4027 // Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future
4028 // will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar
4029 // is used. (The simple C test-case provided in the GLIBC bug report manifests the
4030 // hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos()
4031 // and monitorenter when we're using 1-0 locking. All those operations may result in
4032 // calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version
4033 // of libpthread avoids the problem, but isn't practical.
4034 //
4035 // Possible remedies:
4036 //
4037 // 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work.
4038 // This is palliative and probabilistic, however. If the thread is preempted
4039 // between the call to compute_abstime() and pthread_cond_timedwait(), more
4040 // than the minimum period may have passed, and the abstime may be stale (in the
4041 // past) resultin in a hang. Using this technique reduces the odds of a hang
4042 // but the JVM is still vulnerable, particularly on heavily loaded systems.
4043 //
4044 // 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead
4045 // of the usual flag-condvar-mutex idiom. The write side of the pipe is set
4046 // NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo)
4047 // reduces to poll()+read(). This works well, but consumes 2 FDs per extant
4048 // thread.
4049 //
4050 // 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread
4051 // that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing
4052 // a timeout request to the chron thread and then blocking via pthread_cond_wait().
4053 // This also works well. In fact it avoids kernel-level scalability impediments
4054 // on certain platforms that don't handle lots of active pthread_cond_timedwait()
4055 // timers in a graceful fashion.
4056 //
4057 // 4. When the abstime value is in the past it appears that control returns
4058 // correctly from pthread_cond_timedwait(), but the condvar is left corrupt.
4059 // Subsequent timedwait/wait calls may hang indefinitely. Given that, we
4060 // can avoid the problem by reinitializing the condvar -- by cond_destroy()
4061 // followed by cond_init() -- after all calls to pthread_cond_timedwait().
4062 // It may be possible to avoid reinitialization by checking the return
4063 // value from pthread_cond_timedwait(). In addition to reinitializing the
4064 // condvar we must establish the invariant that cond_signal() is only called
4065 // within critical sections protected by the adjunct mutex. This prevents
4066 // cond_signal() from "seeing" a condvar that's in the midst of being
4067 // reinitialized or that is corrupt. Sadly, this invariant obviates the
4068 // desirable signal-after-unlock optimization that avoids futile context switching.
4069 //
4070 // I'm also concerned that some versions of NTPL might allocate an auxilliary
4071 // structure when a condvar is used or initialized. cond_destroy() would
4072 // release the helper structure. Our reinitialize-after-timedwait fix
4073 // put excessive stress on malloc/free and locks protecting the c-heap.
4074 //
4075 // We currently use (4). See the WorkAroundNTPLTimedWaitHang flag.
4076 // It may be possible to refine (4) by checking the kernel and NTPL verisons
4077 // and only enabling the work-around for vulnerable environments.
4078
4079 // utility to compute the abstime argument to timedwait:
4080 // millis is the relative timeout time
4081 // abstime will be the absolute timeout time
4082 // TODO: replace compute_abstime() with unpackTime()
4083
4084 static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) {
4085 if (millis < 0) millis = 0;
4086 struct timeval now;
4087 int status = gettimeofday(&now, NULL);
4088 assert(status == 0, "gettimeofday");
4089 jlong seconds = millis / 1000;
4090 millis %= 1000;
4091 if (seconds > 50000000) { // see man cond_timedwait(3T)
4092 seconds = 50000000;
4093 }
4094 abstime->tv_sec = now.tv_sec + seconds;
4095 long usec = now.tv_usec + millis * 1000;
4096 if (usec >= 1000000) {
4097 abstime->tv_sec += 1;
4098 usec -= 1000000;
4099 }
4100 abstime->tv_nsec = usec * 1000;
4101 return abstime;
4102 }
4103
4104
4105 // Test-and-clear _Event, always leaves _Event set to 0, returns immediately.
4106 // Conceptually TryPark() should be equivalent to park(0).
4107
4108 int os::PlatformEvent::TryPark() {
4109 for (;;) {
4110 const int v = _Event ;
4111 guarantee ((v == 0) || (v == 1), "invariant") ;
4112 if (Atomic::cmpxchg (0, &_Event, v) == v) return v ;
4113 }
4114 }
4115
4116 void os::PlatformEvent::park() { // AKA "down()"
4117 // Invariant: Only the thread associated with the Event/PlatformEvent
4118 // may call park().
4119 // TODO: assert that _Assoc != NULL or _Assoc == Self
4120 int v ;
4121 for (;;) {
4122 v = _Event ;
4123 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4124 }
4125 guarantee (v >= 0, "invariant") ;
4126 if (v == 0) {
4127 // Do this the hard way by blocking ...
4128 int status = pthread_mutex_lock(_mutex);
4129 assert_status(status == 0, status, "mutex_lock");
4130 guarantee (_nParked == 0, "invariant") ;
4131 ++ _nParked ;
4132 while (_Event < 0) {
4133 status = pthread_cond_wait(_cond, _mutex);
4134 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ...
4135 // Treat this the same as if the wait was interrupted
4136 if (status == ETIMEDOUT) { status = EINTR; }
4137 assert_status(status == 0 || status == EINTR, status, "cond_wait");
4138 }
4139 -- _nParked ;
4140
4141 _Event = 0 ;
4142 status = pthread_mutex_unlock(_mutex);
4143 assert_status(status == 0, status, "mutex_unlock");
4144 // Paranoia to ensure our locked and lock-free paths interact
4145 // correctly with each other.
4146 OrderAccess::fence();
4147 }
4148 guarantee (_Event >= 0, "invariant") ;
4149 }
4150
4151 int os::PlatformEvent::park(jlong millis) {
4152 guarantee (_nParked == 0, "invariant") ;
4153
4154 int v ;
4155 for (;;) {
4156 v = _Event ;
4157 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4158 }
4159 guarantee (v >= 0, "invariant") ;
4160 if (v != 0) return OS_OK ;
4161
4162 // We do this the hard way, by blocking the thread.
4163 // Consider enforcing a minimum timeout value.
4164 struct timespec abst;
4165 compute_abstime(&abst, millis);
4166
4167 int ret = OS_TIMEOUT;
4168 int status = pthread_mutex_lock(_mutex);
4169 assert_status(status == 0, status, "mutex_lock");
4170 guarantee (_nParked == 0, "invariant") ;
4171 ++_nParked ;
4172
4173 // Object.wait(timo) will return because of
4174 // (a) notification
4175 // (b) timeout
4176 // (c) thread.interrupt
4177 //
4178 // Thread.interrupt and object.notify{All} both call Event::set.
4179 // That is, we treat thread.interrupt as a special case of notification.
4180 // The underlying Solaris implementation, cond_timedwait, admits
4181 // spurious/premature wakeups, but the JLS/JVM spec prevents the
4182 // JVM from making those visible to Java code. As such, we must
4183 // filter out spurious wakeups. We assume all ETIME returns are valid.
4184 //
4185 // TODO: properly differentiate simultaneous notify+interrupt.
4186 // In that case, we should propagate the notify to another waiter.
4187
4188 while (_Event < 0) {
4189 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst);
4190 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4191 pthread_cond_destroy (_cond);
4192 pthread_cond_init (_cond, NULL) ;
4193 }
4194 assert_status(status == 0 || status == EINTR ||
4195 status == ETIMEDOUT,
4196 status, "cond_timedwait");
4197 if (!FilterSpuriousWakeups) break ; // previous semantics
4198 if (status == ETIMEDOUT) break ;
4199 // We consume and ignore EINTR and spurious wakeups.
4200 }
4201 --_nParked ;
4202 if (_Event >= 0) {
4203 ret = OS_OK;
4204 }
4205 _Event = 0 ;
4206 status = pthread_mutex_unlock(_mutex);
4207 assert_status(status == 0, status, "mutex_unlock");
4208 assert (_nParked == 0, "invariant") ;
4209 // Paranoia to ensure our locked and lock-free paths interact
4210 // correctly with each other.
4211 OrderAccess::fence();
4212 return ret;
4213 }
4214
4215 void os::PlatformEvent::unpark() {
4216 // Transitions for _Event:
4217 // 0 :=> 1
4218 // 1 :=> 1
4219 // -1 :=> either 0 or 1; must signal target thread
4220 // That is, we can safely transition _Event from -1 to either
4221 // 0 or 1. Forcing 1 is slightly more efficient for back-to-back
4222 // unpark() calls.
4223 // See also: "Semaphores in Plan 9" by Mullender & Cox
4224 //
4225 // Note: Forcing a transition from "-1" to "1" on an unpark() means
4226 // that it will take two back-to-back park() calls for the owning
4227 // thread to block. This has the benefit of forcing a spurious return
4228 // from the first park() call after an unpark() call which will help
4229 // shake out uses of park() and unpark() without condition variables.
4230
4231 if (Atomic::xchg(1, &_Event) >= 0) return;
4232
4233 // Wait for the thread associated with the event to vacate
4234 int status = pthread_mutex_lock(_mutex);
4235 assert_status(status == 0, status, "mutex_lock");
4236 int AnyWaiters = _nParked;
4237 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant");
4238 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) {
4239 AnyWaiters = 0;
4240 pthread_cond_signal(_cond);
4241 }
4242 status = pthread_mutex_unlock(_mutex);
4243 assert_status(status == 0, status, "mutex_unlock");
4244 if (AnyWaiters != 0) {
4245 status = pthread_cond_signal(_cond);
4246 assert_status(status == 0, status, "cond_signal");
4247 }
4248
4249 // Note that we signal() _after dropping the lock for "immortal" Events.
4250 // This is safe and avoids a common class of futile wakeups. In rare
4251 // circumstances this can cause a thread to return prematurely from
4252 // cond_{timed}wait() but the spurious wakeup is benign and the victim will
4253 // simply re-test the condition and re-park itself.
4254 }
4255
4256
4257 // JSR166
4258 // -------------------------------------------------------
4259
4260 /*
4261 * The solaris and bsd implementations of park/unpark are fairly
4262 * conservative for now, but can be improved. They currently use a
4263 * mutex/condvar pair, plus a a count.
4264 * Park decrements count if > 0, else does a condvar wait. Unpark
4265 * sets count to 1 and signals condvar. Only one thread ever waits
4266 * on the condvar. Contention seen when trying to park implies that someone
4267 * is unparking you, so don't wait. And spurious returns are fine, so there
4268 * is no need to track notifications.
4269 */
4270
4271 #define MAX_SECS 100000000
4272 /*
4273 * This code is common to bsd and solaris and will be moved to a
4274 * common place in dolphin.
4275 *
4276 * The passed in time value is either a relative time in nanoseconds
4277 * or an absolute time in milliseconds. Either way it has to be unpacked
4278 * into suitable seconds and nanoseconds components and stored in the
4279 * given timespec structure.
4280 * Given time is a 64-bit value and the time_t used in the timespec is only
4281 * a signed-32-bit value (except on 64-bit Bsd) we have to watch for
4282 * overflow if times way in the future are given. Further on Solaris versions
4283 * prior to 10 there is a restriction (see cond_timedwait) that the specified
4284 * number of seconds, in abstime, is less than current_time + 100,000,000.
4285 * As it will be 28 years before "now + 100000000" will overflow we can
4286 * ignore overflow and just impose a hard-limit on seconds using the value
4287 * of "now + 100,000,000". This places a limit on the timeout of about 3.17
4288 * years from "now".
4289 */
4290
4291 static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) {
4292 assert (time > 0, "convertTime");
4293
4294 struct timeval now;
4295 int status = gettimeofday(&now, NULL);
4296 assert(status == 0, "gettimeofday");
4297
4298 time_t max_secs = now.tv_sec + MAX_SECS;
4299
4300 if (isAbsolute) {
4301 jlong secs = time / 1000;
4302 if (secs > max_secs) {
4303 absTime->tv_sec = max_secs;
4304 }
4305 else {
4306 absTime->tv_sec = secs;
4307 }
4308 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC;
4309 }
4310 else {
4311 jlong secs = time / NANOSECS_PER_SEC;
4312 if (secs >= MAX_SECS) {
4313 absTime->tv_sec = max_secs;
4314 absTime->tv_nsec = 0;
4315 }
4316 else {
4317 absTime->tv_sec = now.tv_sec + secs;
4318 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000;
4319 if (absTime->tv_nsec >= NANOSECS_PER_SEC) {
4320 absTime->tv_nsec -= NANOSECS_PER_SEC;
4321 ++absTime->tv_sec; // note: this must be <= max_secs
4322 }
4323 }
4324 }
4325 assert(absTime->tv_sec >= 0, "tv_sec < 0");
4326 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs");
4327 assert(absTime->tv_nsec >= 0, "tv_nsec < 0");
4328 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec");
4329 }
4330
4331 void Parker::park(bool isAbsolute, jlong time) {
4332 // Ideally we'd do something useful while spinning, such
4333 // as calling unpackTime().
4334
4335 // Optional fast-path check:
4336 // Return immediately if a permit is available.
4337 // We depend on Atomic::xchg() having full barrier semantics
4338 // since we are doing a lock-free update to _counter.
4339 if (Atomic::xchg(0, &_counter) > 0) return;
4340
4341 Thread* thread = Thread::current();
4342 assert(thread->is_Java_thread(), "Must be JavaThread");
4343 JavaThread *jt = (JavaThread *)thread;
4344
4345 // Optional optimization -- avoid state transitions if there's an interrupt pending.
4346 // Check interrupt before trying to wait
4347 if (Thread::is_interrupted(thread, false)) {
4348 return;
4349 }
4350
4351 // Next, demultiplex/decode time arguments
4352 struct timespec absTime;
4353 if (time < 0 || (isAbsolute && time == 0) ) { // don't wait at all
4354 return;
4355 }
4356 if (time > 0) {
4357 unpackTime(&absTime, isAbsolute, time);
4358 }
4359
4360
4361 // Enter safepoint region
4362 // Beware of deadlocks such as 6317397.
4363 // The per-thread Parker:: mutex is a classic leaf-lock.
4364 // In particular a thread must never block on the Threads_lock while
4365 // holding the Parker:: mutex. If safepoints are pending both the
4366 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock.
4367 ThreadBlockInVM tbivm(jt);
4368
4369 // Don't wait if cannot get lock since interference arises from
4370 // unblocking. Also. check interrupt before trying wait
4371 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) {
4372 return;
4373 }
4374
4375 int status ;
4376 if (_counter > 0) { // no wait needed
4377 _counter = 0;
4378 status = pthread_mutex_unlock(_mutex);
4379 assert (status == 0, "invariant") ;
4380 // Paranoia to ensure our locked and lock-free paths interact
4381 // correctly with each other and Java-level accesses.
4382 OrderAccess::fence();
4383 return;
4384 }
4385
4386 #ifdef ASSERT
4387 // Don't catch signals while blocked; let the running threads have the signals.
4388 // (This allows a debugger to break into the running thread.)
4389 sigset_t oldsigs;
4390 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals();
4391 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs);
4392 #endif
4393
4394 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
4395 jt->set_suspend_equivalent();
4396 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
4397
4398 if (time == 0) {
4399 status = pthread_cond_wait (_cond, _mutex) ;
4400 } else {
4401 status = os::Bsd::safe_cond_timedwait (_cond, _mutex, &absTime) ;
4402 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4403 pthread_cond_destroy (_cond) ;
4404 pthread_cond_init (_cond, NULL);
4405 }
4406 }
4407 assert_status(status == 0 || status == EINTR ||
4408 status == ETIMEDOUT,
4409 status, "cond_timedwait");
4410
4411 #ifdef ASSERT
4412 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL);
4413 #endif
4414
4415 _counter = 0 ;
4416 status = pthread_mutex_unlock(_mutex) ;
4417 assert_status(status == 0, status, "invariant") ;
4418 // Paranoia to ensure our locked and lock-free paths interact
4419 // correctly with each other and Java-level accesses.
4420 OrderAccess::fence();
4421
4422 // If externally suspended while waiting, re-suspend
4423 if (jt->handle_special_suspend_equivalent_condition()) {
4424 jt->java_suspend_self();
4425 }
4426 }
4427
4428 void Parker::unpark() {
4429 int s, status ;
4430 status = pthread_mutex_lock(_mutex);
4431 assert (status == 0, "invariant") ;
4432 s = _counter;
4433 _counter = 1;
4434 if (s < 1) {
4435 if (WorkAroundNPTLTimedWaitHang) {
4436 status = pthread_cond_signal (_cond) ;
4437 assert (status == 0, "invariant") ;
4438 status = pthread_mutex_unlock(_mutex);
4439 assert (status == 0, "invariant") ;
4440 } else {
4441 status = pthread_mutex_unlock(_mutex);
4442 assert (status == 0, "invariant") ;
4443 status = pthread_cond_signal (_cond) ;
4444 assert (status == 0, "invariant") ;
4445 }
4446 } else {
4447 pthread_mutex_unlock(_mutex);
4448 assert (status == 0, "invariant") ;
4449 }
4450 }
4451
4452
4453 /* Darwin has no "environ" in a dynamic library. */
4454 #ifdef __APPLE__
4455 #include <crt_externs.h>
4456 #define environ (*_NSGetEnviron())
4457 #else
4458 extern char** environ;
4459 #endif
4460
4461 // Run the specified command in a separate process. Return its exit value,
4462 // or -1 on failure (e.g. can't fork a new process).
4463 // Unlike system(), this function can be called from signal handler. It
4464 // doesn't block SIGINT et al.
4465 int os::fork_and_exec(char* cmd) {
4466 const char * argv[4] = {"sh", "-c", cmd, NULL};
4467
4468 // fork() in BsdThreads/NPTL is not async-safe. It needs to run
4469 // pthread_atfork handlers and reset pthread library. All we need is a
4470 // separate process to execve. Make a direct syscall to fork process.
4471 // On IA64 there's no fork syscall, we have to use fork() and hope for
4472 // the best...
4473 pid_t pid = fork();
4474
4475 if (pid < 0) {
4476 // fork failed
4477 return -1;
4478
4479 } else if (pid == 0) {
4480 // child process
4481
4482 // execve() in BsdThreads will call pthread_kill_other_threads_np()
4483 // first to kill every thread on the thread list. Because this list is
4484 // not reset by fork() (see notes above), execve() will instead kill
4485 // every thread in the parent process. We know this is the only thread
4486 // in the new process, so make a system call directly.
4487 // IA64 should use normal execve() from glibc to match the glibc fork()
4488 // above.
4489 execve("/bin/sh", (char* const*)argv, environ);
4490
4491 // execve failed
4492 _exit(-1);
4493
4494 } else {
4495 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
4496 // care about the actual exit code, for now.
4497
4498 int status;
4499
4500 // Wait for the child process to exit. This returns immediately if
4501 // the child has already exited. */
4502 while (waitpid(pid, &status, 0) < 0) {
4503 switch (errno) {
4504 case ECHILD: return 0;
4505 case EINTR: break;
4506 default: return -1;
4507 }
4508 }
4509
4510 if (WIFEXITED(status)) {
4511 // The child exited normally; get its exit code.
4512 return WEXITSTATUS(status);
4513 } else if (WIFSIGNALED(status)) {
4514 // The child exited because of a signal
4515 // The best value to return is 0x80 + signal number,
4516 // because that is what all Unix shells do, and because
4517 // it allows callers to distinguish between process exit and
4518 // process death by signal.
4519 return 0x80 + WTERMSIG(status);
4520 } else {
4521 // Unknown exit code; pass it through
4522 return status;
4523 }
4524 }
4525 }
4526
4527 // is_headless_jre()
4528 //
4529 // Test for the existence of xawt/libmawt.so or libawt_xawt.so
4530 // in order to report if we are running in a headless jre
4531 //
4532 // Since JDK8 xawt/libmawt.so was moved into the same directory
4533 // as libawt.so, and renamed libawt_xawt.so
4534 //
4535 bool os::is_headless_jre() {
4536 struct stat statbuf;
4537 char buf[MAXPATHLEN];
4538 char libmawtpath[MAXPATHLEN];
4539 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX;
4540 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX;
4541 char *p;
4542
4543 // Get path to libjvm.so
4544 os::jvm_path(buf, sizeof(buf));
4545
4546 // Get rid of libjvm.so
4547 p = strrchr(buf, '/');
4548 if (p == NULL) return false;
4549 else *p = '\0';
4550
4551 // Get rid of client or server
4552 p = strrchr(buf, '/');
4553 if (p == NULL) return false;
4554 else *p = '\0';
4555
4556 // check xawt/libmawt.so
4557 strcpy(libmawtpath, buf);
4558 strcat(libmawtpath, xawtstr);
4559 if (::stat(libmawtpath, &statbuf) == 0) return false;
4560
4561 // check libawt_xawt.so
4562 strcpy(libmawtpath, buf);
4563 strcat(libmawtpath, new_xawtstr);
4564 if (::stat(libmawtpath, &statbuf) == 0) return false;
4565
4566 return true;
4567 }
4568
4569 // Get the default path to the core file
4570 // Returns the length of the string
4571 int os::get_core_path(char* buffer, size_t bufferSize) {
4572 int n = jio_snprintf(buffer, bufferSize, "/cores");
4573
4574 // Truncate if theoretical string was longer than bufferSize
4575 n = MIN2(n, (int)bufferSize);
4576
4577 return n;
4578 }