1 /*
2 * Copyright (c) 1999, 2014, 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 # include <sys/syscall.h>
104
105 #if defined(__FreeBSD__) || defined(__NetBSD__)
106 # include <elf.h>
107 #endif
108
109 #ifdef __APPLE__
110 # include <mach/mach.h> // semaphore_* API
111 # include <mach-o/dyld.h>
112 # include <sys/proc_info.h>
113 # include <objc/objc-auto.h>
114 #endif
115
116 #ifndef MAP_ANONYMOUS
117 #define MAP_ANONYMOUS MAP_ANON
118 #endif
119
120 #define MAX_PATH (2 * K)
121
122 // for timer info max values which include all bits
123 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF)
124
125 #define LARGEPAGES_BIT (1 << 6)
126 ////////////////////////////////////////////////////////////////////////////////
127 // global variables
128 julong os::Bsd::_physical_memory = 0;
129
130
131 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL;
132 pthread_t os::Bsd::_main_thread;
133 int os::Bsd::_page_size = -1;
134
135 static jlong initial_time_count=0;
136
137 static int clock_tics_per_sec = 100;
138
139 // For diagnostics to print a message once. see run_periodic_checks
140 static sigset_t check_signal_done;
141 static bool check_signals = true;
142
143 static pid_t _initial_pid = 0;
144
145 /* Signal number used to suspend/resume a thread */
146
147 /* do not use any signal number less than SIGSEGV, see 4355769 */
148 static int SR_signum = SIGUSR2;
149 sigset_t SR_sigset;
150
151
152 ////////////////////////////////////////////////////////////////////////////////
153 // utility functions
154
155 static int SR_initialize();
156 static void unpackTime(timespec* absTime, bool isAbsolute, jlong time);
157
158 julong os::available_memory() {
159 return Bsd::available_memory();
160 }
161
162 // available here means free
163 julong os::Bsd::available_memory() {
164 uint64_t available = physical_memory() >> 2;
165 #ifdef __APPLE__
166 mach_msg_type_number_t count = HOST_VM_INFO64_COUNT;
167 vm_statistics64_data_t vmstat;
168 kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64,
169 (host_info64_t)&vmstat, &count);
170 assert(kerr == KERN_SUCCESS,
171 "host_statistics64 failed - check mach_host_self() and count");
172 if (kerr == KERN_SUCCESS) {
173 available = vmstat.free_count * os::vm_page_size();
174 }
175 #endif
176 return available;
177 }
178
179 julong os::physical_memory() {
180 return Bsd::physical_memory();
181 }
182
183 ////////////////////////////////////////////////////////////////////////////////
184 // environment support
185
186 bool os::getenv(const char* name, char* buf, int len) {
187 const char* val = ::getenv(name);
188 if (val != NULL && strlen(val) < (size_t)len) {
189 strcpy(buf, val);
190 return true;
191 }
192 if (len > 0) buf[0] = 0; // return a null string
193 return false;
194 }
195
196
197 // Return true if user is running as root.
198
199 bool os::have_special_privileges() {
200 static bool init = false;
201 static bool privileges = false;
202 if (!init) {
203 privileges = (getuid() != geteuid()) || (getgid() != getegid());
204 init = true;
205 }
206 return privileges;
207 }
208
209
210
211 // Cpu architecture string
212 #if defined(ZERO)
213 static char cpu_arch[] = ZERO_LIBARCH;
214 #elif defined(IA64)
215 static char cpu_arch[] = "ia64";
216 #elif defined(IA32)
217 static char cpu_arch[] = "i386";
218 #elif defined(AMD64)
219 static char cpu_arch[] = "amd64";
220 #elif defined(ARM)
221 static char cpu_arch[] = "arm";
222 #elif defined(PPC)
223 static char cpu_arch[] = "ppc";
224 #elif defined(SPARC)
225 # ifdef _LP64
226 static char cpu_arch[] = "sparcv9";
227 # else
228 static char cpu_arch[] = "sparc";
229 # endif
230 #else
231 #error Add appropriate cpu_arch setting
232 #endif
233
234 // Compiler variant
235 #ifdef COMPILER2
236 #define COMPILER_VARIANT "server"
237 #else
238 #define COMPILER_VARIANT "client"
239 #endif
240
241
242 void os::Bsd::initialize_system_info() {
243 int mib[2];
244 size_t len;
245 int cpu_val;
246 julong mem_val;
247
248 /* get processors count via hw.ncpus sysctl */
249 mib[0] = CTL_HW;
250 mib[1] = HW_NCPU;
251 len = sizeof(cpu_val);
252 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) {
253 assert(len == sizeof(cpu_val), "unexpected data size");
254 set_processor_count(cpu_val);
255 }
256 else {
257 set_processor_count(1); // fallback
258 }
259
260 /* get physical memory via hw.memsize sysctl (hw.memsize is used
261 * since it returns a 64 bit value)
262 */
263 mib[0] = CTL_HW;
264
265 #if defined (HW_MEMSIZE) // Apple
266 mib[1] = HW_MEMSIZE;
267 #elif defined(HW_PHYSMEM) // Most of BSD
268 mib[1] = HW_PHYSMEM;
269 #elif defined(HW_REALMEM) // Old FreeBSD
270 mib[1] = HW_REALMEM;
271 #else
272 #error No ways to get physmem
273 #endif
274
275 len = sizeof(mem_val);
276 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) {
277 assert(len == sizeof(mem_val), "unexpected data size");
278 _physical_memory = mem_val;
279 } else {
280 _physical_memory = 256*1024*1024; // fallback (XXXBSD?)
281 }
282
283 #ifdef __OpenBSD__
284 {
285 // limit _physical_memory memory view on OpenBSD since
286 // datasize rlimit restricts us anyway.
287 struct rlimit limits;
288 getrlimit(RLIMIT_DATA, &limits);
289 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur);
290 }
291 #endif
292 }
293
294 #ifdef __APPLE__
295 static const char *get_home() {
296 const char *home_dir = ::getenv("HOME");
297 if ((home_dir == NULL) || (*home_dir == '\0')) {
298 struct passwd *passwd_info = getpwuid(geteuid());
299 if (passwd_info != NULL) {
300 home_dir = passwd_info->pw_dir;
301 }
302 }
303
304 return home_dir;
305 }
306 #endif
307
308 void os::init_system_properties_values() {
309 // char arch[12];
310 // sysinfo(SI_ARCHITECTURE, arch, sizeof(arch));
311
312 // The next steps are taken in the product version:
313 //
314 // Obtain the JAVA_HOME value from the location of libjvm.so.
315 // This library should be located at:
316 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so.
317 //
318 // If "/jre/lib/" appears at the right place in the path, then we
319 // assume libjvm.so is installed in a JDK and we use this path.
320 //
321 // Otherwise exit with message: "Could not create the Java virtual machine."
322 //
323 // The following extra steps are taken in the debugging version:
324 //
325 // If "/jre/lib/" does NOT appear at the right place in the path
326 // instead of exit check for $JAVA_HOME environment variable.
327 //
328 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>,
329 // then we append a fake suffix "hotspot/libjvm.so" to this path so
330 // it looks like libjvm.so is installed there
331 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so.
332 //
333 // Otherwise exit.
334 //
335 // Important note: if the location of libjvm.so changes this
336 // code needs to be changed accordingly.
337
338 // The next few definitions allow the code to be verbatim:
339 #define malloc(n) (char*)NEW_C_HEAP_ARRAY(char, (n), mtInternal)
340 #define getenv(n) ::getenv(n)
341
342 /*
343 * See ld(1):
344 * The linker uses the following search paths to locate required
345 * shared libraries:
346 * 1: ...
347 * ...
348 * 7: The default directories, normally /lib and /usr/lib.
349 */
350 #ifndef DEFAULT_LIBPATH
351 #define DEFAULT_LIBPATH "/lib:/usr/lib"
352 #endif
353
354 #define EXTENSIONS_DIR "/lib/ext"
355 #define ENDORSED_DIR "/lib/endorsed"
356 #define REG_DIR "/usr/java/packages"
357
358 #ifdef __APPLE__
359 #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions"
360 #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java"
361 const char *user_home_dir = get_home();
362 // the null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir
363 int system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) +
364 sizeof(SYS_EXTENSIONS_DIRS);
365 #endif
366
367 {
368 /* sysclasspath, java_home, dll_dir */
369 {
370 char *home_path;
371 char *dll_path;
372 char *pslash;
373 char buf[MAXPATHLEN];
374 os::jvm_path(buf, sizeof(buf));
375
376 // Found the full path to libjvm.so.
377 // Now cut the path to <java_home>/jre if we can.
378 *(strrchr(buf, '/')) = '\0'; /* get rid of /libjvm.so */
379 pslash = strrchr(buf, '/');
380 if (pslash != NULL)
381 *pslash = '\0'; /* get rid of /{client|server|hotspot} */
382 dll_path = malloc(strlen(buf) + 1);
383 if (dll_path == NULL)
384 return;
385 strcpy(dll_path, buf);
386 Arguments::set_dll_dir(dll_path);
387
388 if (pslash != NULL) {
389 pslash = strrchr(buf, '/');
390 if (pslash != NULL) {
391 *pslash = '\0'; /* get rid of /<arch> (/lib on macosx) */
392 #ifndef __APPLE__
393 pslash = strrchr(buf, '/');
394 if (pslash != NULL)
395 *pslash = '\0'; /* get rid of /lib */
396 #endif
397 }
398 }
399
400 home_path = malloc(strlen(buf) + 1);
401 if (home_path == NULL)
402 return;
403 strcpy(home_path, buf);
404 Arguments::set_java_home(home_path);
405
406 if (!set_boot_path('/', ':'))
407 return;
408 }
409
410 /*
411 * Where to look for native libraries
412 *
413 * Note: Due to a legacy implementation, most of the library path
414 * is set in the launcher. This was to accomodate linking restrictions
415 * on legacy Bsd implementations (which are no longer supported).
416 * Eventually, all the library path setting will be done here.
417 *
418 * However, to prevent the proliferation of improperly built native
419 * libraries, the new path component /usr/java/packages is added here.
420 * Eventually, all the library path setting will be done here.
421 */
422 {
423 char *ld_library_path;
424
425 /*
426 * Construct the invariant part of ld_library_path. Note that the
427 * space for the colon and the trailing null are provided by the
428 * nulls included by the sizeof operator (so actually we allocate
429 * a byte more than necessary).
430 */
431 #ifdef __APPLE__
432 ld_library_path = (char *) malloc(system_ext_size);
433 sprintf(ld_library_path, "%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS, user_home_dir);
434 #else
435 ld_library_path = (char *) malloc(sizeof(REG_DIR) + sizeof("/lib/") +
436 strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH));
437 sprintf(ld_library_path, REG_DIR "/lib/%s:" DEFAULT_LIBPATH, cpu_arch);
438 #endif
439
440 /*
441 * Get the user setting of LD_LIBRARY_PATH, and prepended it. It
442 * should always exist (until the legacy problem cited above is
443 * addressed).
444 */
445 #ifdef __APPLE__
446 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code can specify a directory inside an app wrapper
447 char *l = getenv("JAVA_LIBRARY_PATH");
448 if (l != NULL) {
449 char *t = ld_library_path;
450 /* That's +1 for the colon and +1 for the trailing '\0' */
451 ld_library_path = (char *) malloc(strlen(l) + 1 + strlen(t) + 1);
452 sprintf(ld_library_path, "%s:%s", l, t);
453 free(t);
454 }
455
456 char *v = getenv("DYLD_LIBRARY_PATH");
457 #else
458 char *v = getenv("LD_LIBRARY_PATH");
459 #endif
460 if (v != NULL) {
461 char *t = ld_library_path;
462 /* That's +1 for the colon and +1 for the trailing '\0' */
463 ld_library_path = (char *) malloc(strlen(v) + 1 + strlen(t) + 1);
464 sprintf(ld_library_path, "%s:%s", v, t);
465 free(t);
466 }
467
468 #ifdef __APPLE__
469 // Apple's Java6 has "." at the beginning of java.library.path.
470 // OpenJDK on Windows has "." at the end of java.library.path.
471 // OpenJDK on Linux and Solaris don't have "." in java.library.path
472 // at all. To ease the transition from Apple's Java6 to OpenJDK7,
473 // "." is appended to the end of java.library.path. Yes, this
474 // could cause a change in behavior, but Apple's Java6 behavior
475 // can be achieved by putting "." at the beginning of the
476 // JAVA_LIBRARY_PATH environment variable.
477 {
478 char *t = ld_library_path;
479 // that's +3 for appending ":." and the trailing '\0'
480 ld_library_path = (char *) malloc(strlen(t) + 3);
481 sprintf(ld_library_path, "%s:%s", t, ".");
482 free(t);
483 }
484 #endif
485
486 Arguments::set_library_path(ld_library_path);
487 }
488
489 /*
490 * Extensions directories.
491 *
492 * Note that the space for the colon and the trailing null are provided
493 * by the nulls included by the sizeof operator (so actually one byte more
494 * than necessary is allocated).
495 */
496 {
497 #ifdef __APPLE__
498 char *buf = malloc(strlen(Arguments::get_java_home()) +
499 sizeof(EXTENSIONS_DIR) + system_ext_size);
500 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":"
501 SYS_EXTENSIONS_DIRS, user_home_dir, Arguments::get_java_home());
502 #else
503 char *buf = malloc(strlen(Arguments::get_java_home()) +
504 sizeof(EXTENSIONS_DIR) + sizeof(REG_DIR) + sizeof(EXTENSIONS_DIR));
505 sprintf(buf, "%s" EXTENSIONS_DIR ":" REG_DIR EXTENSIONS_DIR,
506 Arguments::get_java_home());
507 #endif
508
509 Arguments::set_ext_dirs(buf);
510 }
511
512 /* Endorsed standards default directory. */
513 {
514 char * buf;
515 buf = malloc(strlen(Arguments::get_java_home()) + sizeof(ENDORSED_DIR));
516 sprintf(buf, "%s" ENDORSED_DIR, Arguments::get_java_home());
517 Arguments::set_endorsed_dirs(buf);
518 }
519 }
520
521 #ifdef __APPLE__
522 #undef SYS_EXTENSIONS_DIR
523 #endif
524 #undef malloc
525 #undef getenv
526 #undef EXTENSIONS_DIR
527 #undef ENDORSED_DIR
528
529 // Done
530 return;
531 }
532
533 ////////////////////////////////////////////////////////////////////////////////
534 // breakpoint support
535
536 void os::breakpoint() {
537 BREAKPOINT;
538 }
539
540 extern "C" void breakpoint() {
541 // use debugger to set breakpoint here
542 }
543
544 ////////////////////////////////////////////////////////////////////////////////
545 // signal support
546
547 debug_only(static bool signal_sets_initialized = false);
548 static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs;
549
550 bool os::Bsd::is_sig_ignored(int sig) {
551 struct sigaction oact;
552 sigaction(sig, (struct sigaction*)NULL, &oact);
553 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction)
554 : CAST_FROM_FN_PTR(void*, oact.sa_handler);
555 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN))
556 return true;
557 else
558 return false;
559 }
560
561 void os::Bsd::signal_sets_init() {
562 // Should also have an assertion stating we are still single-threaded.
563 assert(!signal_sets_initialized, "Already initialized");
564 // Fill in signals that are necessarily unblocked for all threads in
565 // the VM. Currently, we unblock the following signals:
566 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
567 // by -Xrs (=ReduceSignalUsage));
568 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
569 // other threads. The "ReduceSignalUsage" boolean tells us not to alter
570 // the dispositions or masks wrt these signals.
571 // Programs embedding the VM that want to use the above signals for their
572 // own purposes must, at this time, use the "-Xrs" option to prevent
573 // interference with shutdown hooks and BREAK_SIGNAL thread dumping.
574 // (See bug 4345157, and other related bugs).
575 // In reality, though, unblocking these signals is really a nop, since
576 // these signals are not blocked by default.
577 sigemptyset(&unblocked_sigs);
578 sigemptyset(&allowdebug_blocked_sigs);
579 sigaddset(&unblocked_sigs, SIGILL);
580 sigaddset(&unblocked_sigs, SIGSEGV);
581 sigaddset(&unblocked_sigs, SIGBUS);
582 sigaddset(&unblocked_sigs, SIGFPE);
583 sigaddset(&unblocked_sigs, SR_signum);
584
585 if (!ReduceSignalUsage) {
586 if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
587 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
588 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL);
589 }
590 if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
591 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
592 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL);
593 }
594 if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
595 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
596 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL);
597 }
598 }
599 // Fill in signals that are blocked by all but the VM thread.
600 sigemptyset(&vm_sigs);
601 if (!ReduceSignalUsage)
602 sigaddset(&vm_sigs, BREAK_SIGNAL);
603 debug_only(signal_sets_initialized = true);
604
605 }
606
607 // These are signals that are unblocked while a thread is running Java.
608 // (For some reason, they get blocked by default.)
609 sigset_t* os::Bsd::unblocked_signals() {
610 assert(signal_sets_initialized, "Not initialized");
611 return &unblocked_sigs;
612 }
613
614 // These are the signals that are blocked while a (non-VM) thread is
615 // running Java. Only the VM thread handles these signals.
616 sigset_t* os::Bsd::vm_signals() {
617 assert(signal_sets_initialized, "Not initialized");
618 return &vm_sigs;
619 }
620
621 // These are signals that are blocked during cond_wait to allow debugger in
622 sigset_t* os::Bsd::allowdebug_blocked_signals() {
623 assert(signal_sets_initialized, "Not initialized");
624 return &allowdebug_blocked_sigs;
625 }
626
627 void os::Bsd::hotspot_sigmask(Thread* thread) {
628
629 //Save caller's signal mask before setting VM signal mask
630 sigset_t caller_sigmask;
631 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
632
633 OSThread* osthread = thread->osthread();
634 osthread->set_caller_sigmask(caller_sigmask);
635
636 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL);
637
638 if (!ReduceSignalUsage) {
639 if (thread->is_VM_thread()) {
640 // Only the VM thread handles BREAK_SIGNAL ...
641 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
642 } else {
643 // ... all other threads block BREAK_SIGNAL
644 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
645 }
646 }
647 }
648
649
650 //////////////////////////////////////////////////////////////////////////////
651 // create new thread
652
653 // check if it's safe to start a new thread
654 static bool _thread_safety_check(Thread* thread) {
655 return true;
656 }
657
658 #ifdef __APPLE__
659 // library handle for calling objc_registerThreadWithCollector()
660 // without static linking to the libobjc library
661 #define OBJC_LIB "/usr/lib/libobjc.dylib"
662 #define OBJC_GCREGISTER "objc_registerThreadWithCollector"
663 typedef void (*objc_registerThreadWithCollector_t)();
664 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction;
665 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL;
666 #endif
667
668 #ifdef __APPLE__
669 static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) {
670 // Additional thread_id used to correlate threads in SA
671 thread_identifier_info_data_t m_ident_info;
672 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT;
673
674 thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO,
675 (thread_info_t) &m_ident_info, &count);
676
677 return m_ident_info.thread_id;
678 }
679 #endif
680
681 // Thread start routine for all newly created threads
682 static void *java_start(Thread *thread) {
683 // Try to randomize the cache line index of hot stack frames.
684 // This helps when threads of the same stack traces evict each other's
685 // cache lines. The threads can be either from the same JVM instance, or
686 // from different JVM instances. The benefit is especially true for
687 // processors with hyperthreading technology.
688 static int counter = 0;
689 int pid = os::current_process_id();
690 alloca(((pid ^ counter++) & 7) * 128);
691
692 ThreadLocalStorage::set_thread(thread);
693
694 OSThread* osthread = thread->osthread();
695 Monitor* sync = osthread->startThread_lock();
696
697 // non floating stack BsdThreads needs extra check, see above
698 if (!_thread_safety_check(thread)) {
699 // notify parent thread
700 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
701 osthread->set_state(ZOMBIE);
702 sync->notify_all();
703 return NULL;
704 }
705
706 osthread->set_thread_id(os::Bsd::gettid());
707
708 #ifdef __APPLE__
709 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
710 guarantee(unique_thread_id != 0, "unique thread id was not found");
711 osthread->set_unique_thread_id(unique_thread_id);
712 #endif
713 // initialize signal mask for this thread
714 os::Bsd::hotspot_sigmask(thread);
715
716 // initialize floating point control register
717 os::Bsd::init_thread_fpu_state();
718
719 #ifdef __APPLE__
720 // register thread with objc gc
721 if (objc_registerThreadWithCollectorFunction != NULL) {
722 objc_registerThreadWithCollectorFunction();
723 }
724 #endif
725
726 // handshaking with parent thread
727 {
728 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
729
730 // notify parent thread
731 osthread->set_state(INITIALIZED);
732 sync->notify_all();
733
734 // wait until os::start_thread()
735 while (osthread->get_state() == INITIALIZED) {
736 sync->wait(Mutex::_no_safepoint_check_flag);
737 }
738 }
739
740 // call one more level start routine
741 thread->run();
742
743 return 0;
744 }
745
746 bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) {
747 assert(thread->osthread() == NULL, "caller responsible");
748
749 // Allocate the OSThread object
750 OSThread* osthread = new OSThread(NULL, NULL);
751 if (osthread == NULL) {
752 return false;
753 }
754
755 // set the correct thread state
756 osthread->set_thread_type(thr_type);
757
758 // Initial state is ALLOCATED but not INITIALIZED
759 osthread->set_state(ALLOCATED);
760
761 thread->set_osthread(osthread);
762
763 // init thread attributes
764 pthread_attr_t attr;
765 pthread_attr_init(&attr);
766 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
767
768 // stack size
769 if (os::Bsd::supports_variable_stack_size()) {
770 // calculate stack size if it's not specified by caller
771 if (stack_size == 0) {
772 stack_size = os::Bsd::default_stack_size(thr_type);
773
774 switch (thr_type) {
775 case os::java_thread:
776 // Java threads use ThreadStackSize which default value can be
777 // changed with the flag -Xss
778 assert (JavaThread::stack_size_at_create() > 0, "this should be set");
779 stack_size = JavaThread::stack_size_at_create();
780 break;
781 case os::compiler_thread:
782 if (CompilerThreadStackSize > 0) {
783 stack_size = (size_t)(CompilerThreadStackSize * K);
784 break;
785 } // else fall through:
786 // use VMThreadStackSize if CompilerThreadStackSize is not defined
787 case os::vm_thread:
788 case os::pgc_thread:
789 case os::cgc_thread:
790 case os::watcher_thread:
791 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K);
792 break;
793 }
794 }
795
796 stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed);
797 pthread_attr_setstacksize(&attr, stack_size);
798 } else {
799 // let pthread_create() pick the default value.
800 }
801
802 ThreadState state;
803
804 {
805 pthread_t tid;
806 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread);
807
808 pthread_attr_destroy(&attr);
809
810 if (ret != 0) {
811 if (PrintMiscellaneous && (Verbose || WizardMode)) {
812 perror("pthread_create()");
813 }
814 // Need to clean up stuff we've allocated so far
815 thread->set_osthread(NULL);
816 delete osthread;
817 return false;
818 }
819
820 // Store pthread info into the OSThread
821 osthread->set_pthread_id(tid);
822
823 // Wait until child thread is either initialized or aborted
824 {
825 Monitor* sync_with_child = osthread->startThread_lock();
826 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
827 while ((state = osthread->get_state()) == ALLOCATED) {
828 sync_with_child->wait(Mutex::_no_safepoint_check_flag);
829 }
830 }
831
832 }
833
834 // Aborted due to thread limit being reached
835 if (state == ZOMBIE) {
836 thread->set_osthread(NULL);
837 delete osthread;
838 return false;
839 }
840
841 // The thread is returned suspended (in state INITIALIZED),
842 // and is started higher up in the call chain
843 assert(state == INITIALIZED, "race condition");
844 return true;
845 }
846
847 /////////////////////////////////////////////////////////////////////////////
848 // attach existing thread
849
850 // bootstrap the main thread
851 bool os::create_main_thread(JavaThread* thread) {
852 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
853 return create_attached_thread(thread);
854 }
855
856 bool os::create_attached_thread(JavaThread* thread) {
857 #ifdef ASSERT
858 thread->verify_not_published();
859 #endif
860
861 // Allocate the OSThread object
862 OSThread* osthread = new OSThread(NULL, NULL);
863
864 if (osthread == NULL) {
865 return false;
866 }
867
868 osthread->set_thread_id(os::Bsd::gettid());
869
870 // Store pthread info into the OSThread
871 #ifdef __APPLE__
872 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
873 guarantee(unique_thread_id != 0, "just checking");
874 osthread->set_unique_thread_id(unique_thread_id);
875 #endif
876 osthread->set_pthread_id(::pthread_self());
877
878 // initialize floating point control register
879 os::Bsd::init_thread_fpu_state();
880
881 // Initial thread state is RUNNABLE
882 osthread->set_state(RUNNABLE);
883
884 thread->set_osthread(osthread);
885
886 // initialize signal mask for this thread
887 // and save the caller's signal mask
888 os::Bsd::hotspot_sigmask(thread);
889
890 return true;
891 }
892
893 void os::pd_start_thread(Thread* thread) {
894 OSThread * osthread = thread->osthread();
895 assert(osthread->get_state() != INITIALIZED, "just checking");
896 Monitor* sync_with_child = osthread->startThread_lock();
897 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
898 sync_with_child->notify();
899 }
900
901 // Free Bsd resources related to the OSThread
902 void os::free_thread(OSThread* osthread) {
903 assert(osthread != NULL, "osthread not set");
904
905 if (Thread::current()->osthread() == osthread) {
906 // Restore caller's signal mask
907 sigset_t sigmask = osthread->caller_sigmask();
908 pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
909 }
910
911 delete osthread;
912 }
913
914 //////////////////////////////////////////////////////////////////////////////
915 // thread local storage
916
917 int os::allocate_thread_local_storage() {
918 pthread_key_t key;
919 int rslt = pthread_key_create(&key, NULL);
920 assert(rslt == 0, "cannot allocate thread local storage");
921 return (int)key;
922 }
923
924 // Note: This is currently not used by VM, as we don't destroy TLS key
925 // on VM exit.
926 void os::free_thread_local_storage(int index) {
927 int rslt = pthread_key_delete((pthread_key_t)index);
928 assert(rslt == 0, "invalid index");
929 }
930
931 void os::thread_local_storage_at_put(int index, void* value) {
932 int rslt = pthread_setspecific((pthread_key_t)index, value);
933 assert(rslt == 0, "pthread_setspecific failed");
934 }
935
936 extern "C" Thread* get_thread() {
937 return ThreadLocalStorage::thread();
938 }
939
940
941 ////////////////////////////////////////////////////////////////////////////////
942 // time support
943
944 // Time since start-up in seconds to a fine granularity.
945 // Used by VMSelfDestructTimer and the MemProfiler.
946 double os::elapsedTime() {
947
948 return ((double)os::elapsed_counter()) / os::elapsed_frequency();
949 }
950
951 jlong os::elapsed_counter() {
952 return javaTimeNanos() - initial_time_count;
953 }
954
955 jlong os::elapsed_frequency() {
956 return NANOSECS_PER_SEC; // nanosecond resolution
957 }
958
959 bool os::supports_vtime() { return true; }
960 bool os::enable_vtime() { return false; }
961 bool os::vtime_enabled() { return false; }
962
963 double os::elapsedVTime() {
964 // better than nothing, but not much
965 return elapsedTime();
966 }
967
968 jlong os::javaTimeMillis() {
969 timeval time;
970 int status = gettimeofday(&time, NULL);
971 assert(status != -1, "bsd error");
972 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
973 }
974
975 #ifndef CLOCK_MONOTONIC
976 #define CLOCK_MONOTONIC (1)
977 #endif
978
979 #ifdef __APPLE__
980 void os::Bsd::clock_init() {
981 // XXXDARWIN: Investigate replacement monotonic clock
982 }
983 #else
984 void os::Bsd::clock_init() {
985 struct timespec res;
986 struct timespec tp;
987 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
988 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) {
989 // yes, monotonic clock is supported
990 _clock_gettime = ::clock_gettime;
991 }
992 }
993 #endif
994
995
996 jlong os::javaTimeNanos() {
997 if (os::supports_monotonic_clock()) {
998 struct timespec tp;
999 int status = Bsd::clock_gettime(CLOCK_MONOTONIC, &tp);
1000 assert(status == 0, "gettime error");
1001 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
1002 return result;
1003 } else {
1004 timeval time;
1005 int status = gettimeofday(&time, NULL);
1006 assert(status != -1, "bsd error");
1007 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
1008 return 1000 * usecs;
1009 }
1010 }
1011
1012 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
1013 if (os::supports_monotonic_clock()) {
1014 info_ptr->max_value = ALL_64_BITS;
1015
1016 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
1017 info_ptr->may_skip_backward = false; // not subject to resetting or drifting
1018 info_ptr->may_skip_forward = false; // not subject to resetting or drifting
1019 } else {
1020 // gettimeofday - based on time in seconds since the Epoch thus does not wrap
1021 info_ptr->max_value = ALL_64_BITS;
1022
1023 // gettimeofday is a real time clock so it skips
1024 info_ptr->may_skip_backward = true;
1025 info_ptr->may_skip_forward = true;
1026 }
1027
1028 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
1029 }
1030
1031 // Return the real, user, and system times in seconds from an
1032 // arbitrary fixed point in the past.
1033 bool os::getTimesSecs(double* process_real_time,
1034 double* process_user_time,
1035 double* process_system_time) {
1036 struct tms ticks;
1037 clock_t real_ticks = times(&ticks);
1038
1039 if (real_ticks == (clock_t) (-1)) {
1040 return false;
1041 } else {
1042 double ticks_per_second = (double) clock_tics_per_sec;
1043 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1044 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1045 *process_real_time = ((double) real_ticks) / ticks_per_second;
1046
1047 return true;
1048 }
1049 }
1050
1051
1052 char * os::local_time_string(char *buf, size_t buflen) {
1053 struct tm t;
1054 time_t long_time;
1055 time(&long_time);
1056 localtime_r(&long_time, &t);
1057 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1058 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1059 t.tm_hour, t.tm_min, t.tm_sec);
1060 return buf;
1061 }
1062
1063 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
1064 return localtime_r(clock, res);
1065 }
1066
1067 ////////////////////////////////////////////////////////////////////////////////
1068 // runtime exit support
1069
1070 // Note: os::shutdown() might be called very early during initialization, or
1071 // called from signal handler. Before adding something to os::shutdown(), make
1072 // sure it is async-safe and can handle partially initialized VM.
1073 void os::shutdown() {
1074
1075 // allow PerfMemory to attempt cleanup of any persistent resources
1076 perfMemory_exit();
1077
1078 // needs to remove object in file system
1079 AttachListener::abort();
1080
1081 // flush buffered output, finish log files
1082 ostream_abort();
1083
1084 // Check for abort hook
1085 abort_hook_t abort_hook = Arguments::abort_hook();
1086 if (abort_hook != NULL) {
1087 abort_hook();
1088 }
1089
1090 }
1091
1092 // Note: os::abort() might be called very early during initialization, or
1093 // called from signal handler. Before adding something to os::abort(), make
1094 // sure it is async-safe and can handle partially initialized VM.
1095 void os::abort(bool dump_core) {
1096 os::shutdown();
1097 if (dump_core) {
1098 #ifndef PRODUCT
1099 fdStream out(defaultStream::output_fd());
1100 out.print_raw("Current thread is ");
1101 char buf[16];
1102 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
1103 out.print_raw_cr(buf);
1104 out.print_raw_cr("Dumping core ...");
1105 #endif
1106 ::abort(); // dump core
1107 }
1108
1109 ::exit(1);
1110 }
1111
1112 // Die immediately, no exit hook, no abort hook, no cleanup.
1113 void os::die() {
1114 // _exit() on BsdThreads only kills current thread
1115 ::abort();
1116 }
1117
1118 // unused on bsd for now.
1119 void os::set_error_file(const char *logfile) {}
1120
1121
1122 // This method is a copy of JDK's sysGetLastErrorString
1123 // from src/solaris/hpi/src/system_md.c
1124
1125 size_t os::lasterror(char *buf, size_t len) {
1126
1127 if (errno == 0) return 0;
1128
1129 const char *s = ::strerror(errno);
1130 size_t n = ::strlen(s);
1131 if (n >= len) {
1132 n = len - 1;
1133 }
1134 ::strncpy(buf, s, n);
1135 buf[n] = '\0';
1136 return n;
1137 }
1138
1139 // Information of current thread in variety of formats
1140 pid_t os::Bsd::gettid() {
1141 int retval = -1;
1142
1143 #ifdef __APPLE__ //XNU kernel
1144 // despite the fact mach port is actually not a thread id use it
1145 // instead of syscall(SYS_thread_selfid) as it certainly fits to u4
1146 retval = ::pthread_mach_thread_np(::pthread_self());
1147 guarantee(retval != 0, "just checking");
1148 return retval;
1149
1150 #elif __FreeBSD__
1151 retval = syscall(SYS_thr_self);
1152 #elif __OpenBSD__
1153 retval = syscall(SYS_getthrid);
1154 #elif __NetBSD__
1155 retval = (pid_t) syscall(SYS__lwp_self);
1156 #endif
1157
1158 if (retval == -1) {
1159 return getpid();
1160 }
1161 }
1162
1163 intx os::current_thread_id() {
1164 #ifdef __APPLE__
1165 return (intx)::pthread_mach_thread_np(::pthread_self());
1166 #else
1167 return (intx)::pthread_self();
1168 #endif
1169 }
1170
1171 int os::current_process_id() {
1172
1173 // Under the old bsd thread library, bsd gives each thread
1174 // its own process id. Because of this each thread will return
1175 // a different pid if this method were to return the result
1176 // of getpid(2). Bsd provides no api that returns the pid
1177 // of the launcher thread for the vm. This implementation
1178 // returns a unique pid, the pid of the launcher thread
1179 // that starts the vm 'process'.
1180
1181 // Under the NPTL, getpid() returns the same pid as the
1182 // launcher thread rather than a unique pid per thread.
1183 // Use gettid() if you want the old pre NPTL behaviour.
1184
1185 // if you are looking for the result of a call to getpid() that
1186 // returns a unique pid for the calling thread, then look at the
1187 // OSThread::thread_id() method in osThread_bsd.hpp file
1188
1189 return (int)(_initial_pid ? _initial_pid : getpid());
1190 }
1191
1192 // DLL functions
1193
1194 #define JNI_LIB_PREFIX "lib"
1195 #ifdef __APPLE__
1196 #define JNI_LIB_SUFFIX ".dylib"
1197 #else
1198 #define JNI_LIB_SUFFIX ".so"
1199 #endif
1200
1201 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1202
1203 // This must be hard coded because it's the system's temporary
1204 // directory not the java application's temp directory, ala java.io.tmpdir.
1205 #ifdef __APPLE__
1206 // macosx has a secure per-user temporary directory
1207 char temp_path_storage[PATH_MAX];
1208 const char* os::get_temp_directory() {
1209 static char *temp_path = NULL;
1210 if (temp_path == NULL) {
1211 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
1212 if (pathSize == 0 || pathSize > PATH_MAX) {
1213 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
1214 }
1215 temp_path = temp_path_storage;
1216 }
1217 return temp_path;
1218 }
1219 #else /* __APPLE__ */
1220 const char* os::get_temp_directory() { return "/tmp"; }
1221 #endif /* __APPLE__ */
1222
1223 static bool file_exists(const char* filename) {
1224 struct stat statbuf;
1225 if (filename == NULL || strlen(filename) == 0) {
1226 return false;
1227 }
1228 return os::stat(filename, &statbuf) == 0;
1229 }
1230
1231 bool os::dll_build_name(char* buffer, size_t buflen,
1232 const char* pname, const char* fname) {
1233 bool retval = false;
1234 // Copied from libhpi
1235 const size_t pnamelen = pname ? strlen(pname) : 0;
1236
1237 // Return error on buffer overflow.
1238 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) {
1239 return retval;
1240 }
1241
1242 if (pnamelen == 0) {
1243 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname);
1244 retval = true;
1245 } else if (strchr(pname, *os::path_separator()) != NULL) {
1246 int n;
1247 char** pelements = split_path(pname, &n);
1248 if (pelements == NULL) {
1249 return false;
1250 }
1251 for (int i = 0 ; i < n ; i++) {
1252 // Really shouldn't be NULL, but check can't hurt
1253 if (pelements[i] == NULL || strlen(pelements[i]) == 0) {
1254 continue; // skip the empty path values
1255 }
1256 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX,
1257 pelements[i], fname);
1258 if (file_exists(buffer)) {
1259 retval = true;
1260 break;
1261 }
1262 }
1263 // release the storage
1264 for (int i = 0 ; i < n ; i++) {
1265 if (pelements[i] != NULL) {
1266 FREE_C_HEAP_ARRAY(char, pelements[i], mtInternal);
1267 }
1268 }
1269 if (pelements != NULL) {
1270 FREE_C_HEAP_ARRAY(char*, pelements, mtInternal);
1271 }
1272 } else {
1273 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname);
1274 retval = true;
1275 }
1276 return retval;
1277 }
1278
1279 // check if addr is inside libjvm.so
1280 bool os::address_is_in_vm(address addr) {
1281 static address libjvm_base_addr;
1282 Dl_info dlinfo;
1283
1284 if (libjvm_base_addr == NULL) {
1285 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) {
1286 libjvm_base_addr = (address)dlinfo.dli_fbase;
1287 }
1288 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1289 }
1290
1291 if (dladdr((void *)addr, &dlinfo) != 0) {
1292 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1293 }
1294
1295 return false;
1296 }
1297
1298
1299 #define MACH_MAXSYMLEN 256
1300
1301 bool os::dll_address_to_function_name(address addr, char *buf,
1302 int buflen, int *offset) {
1303 // buf is not optional, but offset is optional
1304 assert(buf != NULL, "sanity check");
1305
1306 Dl_info dlinfo;
1307 char localbuf[MACH_MAXSYMLEN];
1308
1309 if (dladdr((void*)addr, &dlinfo) != 0) {
1310 // see if we have a matching symbol
1311 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) {
1312 if (!Decoder::demangle(dlinfo.dli_sname, buf, buflen)) {
1313 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1314 }
1315 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1316 return true;
1317 }
1318 // no matching symbol so try for just file info
1319 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) {
1320 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1321 buf, buflen, offset, dlinfo.dli_fname)) {
1322 return true;
1323 }
1324 }
1325
1326 // Handle non-dynamic manually:
1327 if (dlinfo.dli_fbase != NULL &&
1328 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset,
1329 dlinfo.dli_fbase)) {
1330 if (!Decoder::demangle(localbuf, buf, buflen)) {
1331 jio_snprintf(buf, buflen, "%s", localbuf);
1332 }
1333 return true;
1334 }
1335 }
1336 buf[0] = '\0';
1337 if (offset != NULL) *offset = -1;
1338 return false;
1339 }
1340
1341 // ported from solaris version
1342 bool os::dll_address_to_library_name(address addr, char* buf,
1343 int buflen, int* offset) {
1344 // buf is not optional, but offset is optional
1345 assert(buf != NULL, "sanity check");
1346
1347 Dl_info dlinfo;
1348
1349 if (dladdr((void*)addr, &dlinfo) != 0) {
1350 if (dlinfo.dli_fname != NULL) {
1351 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1352 }
1353 if (dlinfo.dli_fbase != NULL && offset != NULL) {
1354 *offset = addr - (address)dlinfo.dli_fbase;
1355 }
1356 return true;
1357 }
1358
1359 buf[0] = '\0';
1360 if (offset) *offset = -1;
1361 return false;
1362 }
1363
1364 // Loads .dll/.so and
1365 // in case of error it checks if .dll/.so was built for the
1366 // same architecture as Hotspot is running on
1367
1368 #ifdef __APPLE__
1369 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1370 void * result= ::dlopen(filename, RTLD_LAZY);
1371 if (result != NULL) {
1372 // Successful loading
1373 return result;
1374 }
1375
1376 // Read system error message into ebuf
1377 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1378 ebuf[ebuflen-1]='\0';
1379
1380 return NULL;
1381 }
1382 #else
1383 void * os::dll_load(const char *filename, char *ebuf, int ebuflen)
1384 {
1385 void * result= ::dlopen(filename, RTLD_LAZY);
1386 if (result != NULL) {
1387 // Successful loading
1388 return result;
1389 }
1390
1391 Elf32_Ehdr elf_head;
1392
1393 // Read system error message into ebuf
1394 // It may or may not be overwritten below
1395 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1396 ebuf[ebuflen-1]='\0';
1397 int diag_msg_max_length=ebuflen-strlen(ebuf);
1398 char* diag_msg_buf=ebuf+strlen(ebuf);
1399
1400 if (diag_msg_max_length==0) {
1401 // No more space in ebuf for additional diagnostics message
1402 return NULL;
1403 }
1404
1405
1406 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1407
1408 if (file_descriptor < 0) {
1409 // Can't open library, report dlerror() message
1410 return NULL;
1411 }
1412
1413 bool failed_to_read_elf_head=
1414 (sizeof(elf_head)!=
1415 (::read(file_descriptor, &elf_head,sizeof(elf_head)))) ;
1416
1417 ::close(file_descriptor);
1418 if (failed_to_read_elf_head) {
1419 // file i/o error - report dlerror() msg
1420 return NULL;
1421 }
1422
1423 typedef struct {
1424 Elf32_Half code; // Actual value as defined in elf.h
1425 Elf32_Half compat_class; // Compatibility of archs at VM's sense
1426 char elf_class; // 32 or 64 bit
1427 char endianess; // MSB or LSB
1428 char* name; // String representation
1429 } arch_t;
1430
1431 #ifndef EM_486
1432 #define EM_486 6 /* Intel 80486 */
1433 #endif
1434
1435 #ifndef EM_MIPS_RS3_LE
1436 #define EM_MIPS_RS3_LE 10 /* MIPS */
1437 #endif
1438
1439 #ifndef EM_PPC64
1440 #define EM_PPC64 21 /* PowerPC64 */
1441 #endif
1442
1443 #ifndef EM_S390
1444 #define EM_S390 22 /* IBM System/390 */
1445 #endif
1446
1447 #ifndef EM_IA_64
1448 #define EM_IA_64 50 /* HP/Intel IA-64 */
1449 #endif
1450
1451 #ifndef EM_X86_64
1452 #define EM_X86_64 62 /* AMD x86-64 */
1453 #endif
1454
1455 static const arch_t arch_array[]={
1456 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1457 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1458 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
1459 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
1460 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1461 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1462 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
1463 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
1464 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
1465 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"},
1466 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
1467 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
1468 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
1469 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
1470 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
1471 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
1472 };
1473
1474 #if (defined IA32)
1475 static Elf32_Half running_arch_code=EM_386;
1476 #elif (defined AMD64)
1477 static Elf32_Half running_arch_code=EM_X86_64;
1478 #elif (defined IA64)
1479 static Elf32_Half running_arch_code=EM_IA_64;
1480 #elif (defined __sparc) && (defined _LP64)
1481 static Elf32_Half running_arch_code=EM_SPARCV9;
1482 #elif (defined __sparc) && (!defined _LP64)
1483 static Elf32_Half running_arch_code=EM_SPARC;
1484 #elif (defined __powerpc64__)
1485 static Elf32_Half running_arch_code=EM_PPC64;
1486 #elif (defined __powerpc__)
1487 static Elf32_Half running_arch_code=EM_PPC;
1488 #elif (defined ARM)
1489 static Elf32_Half running_arch_code=EM_ARM;
1490 #elif (defined S390)
1491 static Elf32_Half running_arch_code=EM_S390;
1492 #elif (defined ALPHA)
1493 static Elf32_Half running_arch_code=EM_ALPHA;
1494 #elif (defined MIPSEL)
1495 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
1496 #elif (defined PARISC)
1497 static Elf32_Half running_arch_code=EM_PARISC;
1498 #elif (defined MIPS)
1499 static Elf32_Half running_arch_code=EM_MIPS;
1500 #elif (defined M68K)
1501 static Elf32_Half running_arch_code=EM_68K;
1502 #else
1503 #error Method os::dll_load requires that one of following is defined:\
1504 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
1505 #endif
1506
1507 // Identify compatability class for VM's architecture and library's architecture
1508 // Obtain string descriptions for architectures
1509
1510 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
1511 int running_arch_index=-1;
1512
1513 for (unsigned int i=0 ; i < ARRAY_SIZE(arch_array) ; i++ ) {
1514 if (running_arch_code == arch_array[i].code) {
1515 running_arch_index = i;
1516 }
1517 if (lib_arch.code == arch_array[i].code) {
1518 lib_arch.compat_class = arch_array[i].compat_class;
1519 lib_arch.name = arch_array[i].name;
1520 }
1521 }
1522
1523 assert(running_arch_index != -1,
1524 "Didn't find running architecture code (running_arch_code) in arch_array");
1525 if (running_arch_index == -1) {
1526 // Even though running architecture detection failed
1527 // we may still continue with reporting dlerror() message
1528 return NULL;
1529 }
1530
1531 if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
1532 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
1533 return NULL;
1534 }
1535
1536 #ifndef S390
1537 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
1538 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
1539 return NULL;
1540 }
1541 #endif // !S390
1542
1543 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
1544 if ( lib_arch.name!=NULL ) {
1545 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1546 " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
1547 lib_arch.name, arch_array[running_arch_index].name);
1548 } else {
1549 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1550 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
1551 lib_arch.code,
1552 arch_array[running_arch_index].name);
1553 }
1554 }
1555
1556 return NULL;
1557 }
1558 #endif /* !__APPLE__ */
1559
1560 void* os::get_default_process_handle() {
1561 #ifdef __APPLE__
1562 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY
1563 // to avoid finding unexpected symbols on second (or later)
1564 // loads of a library.
1565 return (void*)::dlopen(NULL, RTLD_FIRST);
1566 #else
1567 return (void*)::dlopen(NULL, RTLD_LAZY);
1568 #endif
1569 }
1570
1571 // XXX: Do we need a lock around this as per Linux?
1572 void* os::dll_lookup(void* handle, const char* name) {
1573 return dlsym(handle, name);
1574 }
1575
1576
1577 static bool _print_ascii_file(const char* filename, outputStream* st) {
1578 int fd = ::open(filename, O_RDONLY);
1579 if (fd == -1) {
1580 return false;
1581 }
1582
1583 char buf[32];
1584 int bytes;
1585 while ((bytes = ::read(fd, buf, sizeof(buf))) > 0) {
1586 st->print_raw(buf, bytes);
1587 }
1588
1589 ::close(fd);
1590
1591 return true;
1592 }
1593
1594 void os::print_dll_info(outputStream *st) {
1595 st->print_cr("Dynamic libraries:");
1596 #ifdef RTLD_DI_LINKMAP
1597 Dl_info dli;
1598 void *handle;
1599 Link_map *map;
1600 Link_map *p;
1601
1602 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 ||
1603 dli.dli_fname == NULL) {
1604 st->print_cr("Error: Cannot print dynamic libraries.");
1605 return;
1606 }
1607 handle = dlopen(dli.dli_fname, RTLD_LAZY);
1608 if (handle == NULL) {
1609 st->print_cr("Error: Cannot print dynamic libraries.");
1610 return;
1611 }
1612 dlinfo(handle, RTLD_DI_LINKMAP, &map);
1613 if (map == NULL) {
1614 st->print_cr("Error: Cannot print dynamic libraries.");
1615 return;
1616 }
1617
1618 while (map->l_prev != NULL)
1619 map = map->l_prev;
1620
1621 while (map != NULL) {
1622 st->print_cr(PTR_FORMAT " \t%s", map->l_addr, map->l_name);
1623 map = map->l_next;
1624 }
1625
1626 dlclose(handle);
1627 #elif defined(__APPLE__)
1628 uint32_t count;
1629 uint32_t i;
1630
1631 count = _dyld_image_count();
1632 for (i = 1; i < count; i++) {
1633 const char *name = _dyld_get_image_name(i);
1634 intptr_t slide = _dyld_get_image_vmaddr_slide(i);
1635 st->print_cr(PTR_FORMAT " \t%s", slide, name);
1636 }
1637 #else
1638 st->print_cr("Error: Cannot print dynamic libraries.");
1639 #endif
1640 }
1641
1642 void os::print_os_info_brief(outputStream* st) {
1643 st->print("Bsd");
1644
1645 os::Posix::print_uname_info(st);
1646 }
1647
1648 void os::print_os_info(outputStream* st) {
1649 st->print("OS:");
1650 st->print("Bsd");
1651
1652 os::Posix::print_uname_info(st);
1653
1654 os::Posix::print_rlimit_info(st);
1655
1656 os::Posix::print_load_average(st);
1657 }
1658
1659 void os::pd_print_cpu_info(outputStream* st) {
1660 // Nothing to do for now.
1661 }
1662
1663 void os::print_memory_info(outputStream* st) {
1664
1665 st->print("Memory:");
1666 st->print(" %dk page", os::vm_page_size()>>10);
1667
1668 st->print(", physical " UINT64_FORMAT "k",
1669 os::physical_memory() >> 10);
1670 st->print("(" UINT64_FORMAT "k free)",
1671 os::available_memory() >> 10);
1672 st->cr();
1673
1674 // meminfo
1675 st->print("\n/proc/meminfo:\n");
1676 _print_ascii_file("/proc/meminfo", st);
1677 st->cr();
1678 }
1679
1680 // Taken from /usr/include/bits/siginfo.h Supposed to be architecture specific
1681 // but they're the same for all the bsd arch that we support
1682 // and they're the same for solaris but there's no common place to put this.
1683 const char *ill_names[] = { "ILL0", "ILL_ILLOPC", "ILL_ILLOPN", "ILL_ILLADR",
1684 "ILL_ILLTRP", "ILL_PRVOPC", "ILL_PRVREG",
1685 "ILL_COPROC", "ILL_BADSTK" };
1686
1687 const char *fpe_names[] = { "FPE0", "FPE_INTDIV", "FPE_INTOVF", "FPE_FLTDIV",
1688 "FPE_FLTOVF", "FPE_FLTUND", "FPE_FLTRES",
1689 "FPE_FLTINV", "FPE_FLTSUB", "FPE_FLTDEN" };
1690
1691 const char *segv_names[] = { "SEGV0", "SEGV_MAPERR", "SEGV_ACCERR" };
1692
1693 const char *bus_names[] = { "BUS0", "BUS_ADRALN", "BUS_ADRERR", "BUS_OBJERR" };
1694
1695 void os::print_siginfo(outputStream* st, void* siginfo) {
1696 st->print("siginfo:");
1697
1698 const int buflen = 100;
1699 char buf[buflen];
1700 siginfo_t *si = (siginfo_t*)siginfo;
1701 st->print("si_signo=%s: ", os::exception_name(si->si_signo, buf, buflen));
1702 if (si->si_errno != 0 && strerror_r(si->si_errno, buf, buflen) == 0) {
1703 st->print("si_errno=%s", buf);
1704 } else {
1705 st->print("si_errno=%d", si->si_errno);
1706 }
1707 const int c = si->si_code;
1708 assert(c > 0, "unexpected si_code");
1709 switch (si->si_signo) {
1710 case SIGILL:
1711 st->print(", si_code=%d (%s)", c, c > 8 ? "" : ill_names[c]);
1712 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1713 break;
1714 case SIGFPE:
1715 st->print(", si_code=%d (%s)", c, c > 9 ? "" : fpe_names[c]);
1716 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1717 break;
1718 case SIGSEGV:
1719 st->print(", si_code=%d (%s)", c, c > 2 ? "" : segv_names[c]);
1720 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1721 break;
1722 case SIGBUS:
1723 st->print(", si_code=%d (%s)", c, c > 3 ? "" : bus_names[c]);
1724 st->print(", si_addr=" PTR_FORMAT, si->si_addr);
1725 break;
1726 default:
1727 st->print(", si_code=%d", si->si_code);
1728 // no si_addr
1729 }
1730
1731 if ((si->si_signo == SIGBUS || si->si_signo == SIGSEGV) &&
1732 UseSharedSpaces) {
1733 FileMapInfo* mapinfo = FileMapInfo::current_info();
1734 if (mapinfo->is_in_shared_space(si->si_addr)) {
1735 st->print("\n\nError accessing class data sharing archive." \
1736 " Mapped file inaccessible during execution, " \
1737 " possible disk/network problem.");
1738 }
1739 }
1740 st->cr();
1741 }
1742
1743
1744 static void print_signal_handler(outputStream* st, int sig,
1745 char* buf, size_t buflen);
1746
1747 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1748 st->print_cr("Signal Handlers:");
1749 print_signal_handler(st, SIGSEGV, buf, buflen);
1750 print_signal_handler(st, SIGBUS , buf, buflen);
1751 print_signal_handler(st, SIGFPE , buf, buflen);
1752 print_signal_handler(st, SIGPIPE, buf, buflen);
1753 print_signal_handler(st, SIGXFSZ, buf, buflen);
1754 print_signal_handler(st, SIGILL , buf, buflen);
1755 print_signal_handler(st, INTERRUPT_SIGNAL, buf, buflen);
1756 print_signal_handler(st, SR_signum, buf, buflen);
1757 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1758 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1759 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1760 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1761 }
1762
1763 static char saved_jvm_path[MAXPATHLEN] = {0};
1764
1765 // Find the full path to the current module, libjvm
1766 void os::jvm_path(char *buf, jint buflen) {
1767 // Error checking.
1768 if (buflen < MAXPATHLEN) {
1769 assert(false, "must use a large-enough buffer");
1770 buf[0] = '\0';
1771 return;
1772 }
1773 // Lazy resolve the path to current module.
1774 if (saved_jvm_path[0] != 0) {
1775 strcpy(buf, saved_jvm_path);
1776 return;
1777 }
1778
1779 char dli_fname[MAXPATHLEN];
1780 bool ret = dll_address_to_library_name(
1781 CAST_FROM_FN_PTR(address, os::jvm_path),
1782 dli_fname, sizeof(dli_fname), NULL);
1783 assert(ret, "cannot locate libjvm");
1784 char *rp = NULL;
1785 if (ret && dli_fname[0] != '\0') {
1786 rp = realpath(dli_fname, buf);
1787 }
1788 if (rp == NULL)
1789 return;
1790
1791 if (Arguments::sun_java_launcher_is_altjvm()) {
1792 // Support for the java launcher's '-XXaltjvm=<path>' option. Typical
1793 // value for buf is "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so"
1794 // or "<JAVA_HOME>/jre/lib/<vmtype>/libjvm.dylib". If "/jre/lib/"
1795 // appears at the right place in the string, then assume we are
1796 // installed in a JDK and we're done. Otherwise, check for a
1797 // JAVA_HOME environment variable and construct a path to the JVM
1798 // being overridden.
1799
1800 const char *p = buf + strlen(buf) - 1;
1801 for (int count = 0; p > buf && count < 5; ++count) {
1802 for (--p; p > buf && *p != '/'; --p)
1803 /* empty */ ;
1804 }
1805
1806 if (strncmp(p, "/jre/lib/", 9) != 0) {
1807 // Look for JAVA_HOME in the environment.
1808 char* java_home_var = ::getenv("JAVA_HOME");
1809 if (java_home_var != NULL && java_home_var[0] != 0) {
1810 char* jrelib_p;
1811 int len;
1812
1813 // Check the current module name "libjvm"
1814 p = strrchr(buf, '/');
1815 assert(strstr(p, "/libjvm") == p, "invalid library name");
1816
1817 rp = realpath(java_home_var, buf);
1818 if (rp == NULL)
1819 return;
1820
1821 // determine if this is a legacy image or modules image
1822 // modules image doesn't have "jre" subdirectory
1823 len = strlen(buf);
1824 jrelib_p = buf + len;
1825
1826 // Add the appropriate library subdir
1827 snprintf(jrelib_p, buflen-len, "/jre/lib");
1828 if (0 != access(buf, F_OK)) {
1829 snprintf(jrelib_p, buflen-len, "/lib");
1830 }
1831
1832 // Add the appropriate client or server subdir
1833 len = strlen(buf);
1834 jrelib_p = buf + len;
1835 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
1836 if (0 != access(buf, F_OK)) {
1837 snprintf(jrelib_p, buflen-len, "%s", "");
1838 }
1839
1840 // If the path exists within JAVA_HOME, add the JVM library name
1841 // to complete the path to JVM being overridden. Otherwise fallback
1842 // to the path to the current library.
1843 if (0 == access(buf, F_OK)) {
1844 // Use current module name "libjvm"
1845 len = strlen(buf);
1846 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
1847 } else {
1848 // Fall back to path of current library
1849 rp = realpath(dli_fname, buf);
1850 if (rp == NULL)
1851 return;
1852 }
1853 }
1854 }
1855 }
1856
1857 strcpy(saved_jvm_path, buf);
1858 }
1859
1860 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1861 // no prefix required, not even "_"
1862 }
1863
1864 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1865 // no suffix required
1866 }
1867
1868 ////////////////////////////////////////////////////////////////////////////////
1869 // sun.misc.Signal support
1870
1871 static volatile jint sigint_count = 0;
1872
1873 static void
1874 UserHandler(int sig, void *siginfo, void *context) {
1875 // 4511530 - sem_post is serialized and handled by the manager thread. When
1876 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
1877 // don't want to flood the manager thread with sem_post requests.
1878 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1)
1879 return;
1880
1881 // Ctrl-C is pressed during error reporting, likely because the error
1882 // handler fails to abort. Let VM die immediately.
1883 if (sig == SIGINT && is_error_reported()) {
1884 os::die();
1885 }
1886
1887 os::signal_notify(sig);
1888 }
1889
1890 void* os::user_handler() {
1891 return CAST_FROM_FN_PTR(void*, UserHandler);
1892 }
1893
1894 extern "C" {
1895 typedef void (*sa_handler_t)(int);
1896 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1897 }
1898
1899 void* os::signal(int signal_number, void* handler) {
1900 struct sigaction sigAct, oldSigAct;
1901
1902 sigfillset(&(sigAct.sa_mask));
1903 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
1904 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1905
1906 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1907 // -1 means registration failed
1908 return (void *)-1;
1909 }
1910
1911 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1912 }
1913
1914 void os::signal_raise(int signal_number) {
1915 ::raise(signal_number);
1916 }
1917
1918 /*
1919 * The following code is moved from os.cpp for making this
1920 * code platform specific, which it is by its very nature.
1921 */
1922
1923 // Will be modified when max signal is changed to be dynamic
1924 int os::sigexitnum_pd() {
1925 return NSIG;
1926 }
1927
1928 // a counter for each possible signal value
1929 static volatile jint pending_signals[NSIG+1] = { 0 };
1930
1931 // Bsd(POSIX) specific hand shaking semaphore.
1932 #ifdef __APPLE__
1933 typedef semaphore_t os_semaphore_t;
1934 #define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value)
1935 #define SEM_WAIT(sem) semaphore_wait(sem)
1936 #define SEM_POST(sem) semaphore_signal(sem)
1937 #define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem)
1938 #else
1939 typedef sem_t os_semaphore_t;
1940 #define SEM_INIT(sem, value) sem_init(&sem, 0, value)
1941 #define SEM_WAIT(sem) sem_wait(&sem)
1942 #define SEM_POST(sem) sem_post(&sem)
1943 #define SEM_DESTROY(sem) sem_destroy(&sem)
1944 #endif
1945
1946 class Semaphore : public StackObj {
1947 public:
1948 Semaphore();
1949 ~Semaphore();
1950 void signal();
1951 void wait();
1952 bool trywait();
1953 bool timedwait(unsigned int sec, int nsec);
1954 private:
1955 jlong currenttime() const;
1956 os_semaphore_t _semaphore;
1957 };
1958
1959 Semaphore::Semaphore() : _semaphore(0) {
1960 SEM_INIT(_semaphore, 0);
1961 }
1962
1963 Semaphore::~Semaphore() {
1964 SEM_DESTROY(_semaphore);
1965 }
1966
1967 void Semaphore::signal() {
1968 SEM_POST(_semaphore);
1969 }
1970
1971 void Semaphore::wait() {
1972 SEM_WAIT(_semaphore);
1973 }
1974
1975 jlong Semaphore::currenttime() const {
1976 struct timeval tv;
1977 gettimeofday(&tv, NULL);
1978 return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000);
1979 }
1980
1981 #ifdef __APPLE__
1982 bool Semaphore::trywait() {
1983 return timedwait(0, 0);
1984 }
1985
1986 bool Semaphore::timedwait(unsigned int sec, int nsec) {
1987 kern_return_t kr = KERN_ABORTED;
1988 mach_timespec_t waitspec;
1989 waitspec.tv_sec = sec;
1990 waitspec.tv_nsec = nsec;
1991
1992 jlong starttime = currenttime();
1993
1994 kr = semaphore_timedwait(_semaphore, waitspec);
1995 while (kr == KERN_ABORTED) {
1996 jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec;
1997
1998 jlong current = currenttime();
1999 jlong passedtime = current - starttime;
2000
2001 if (passedtime >= totalwait) {
2002 waitspec.tv_sec = 0;
2003 waitspec.tv_nsec = 0;
2004 } else {
2005 jlong waittime = totalwait - (current - starttime);
2006 waitspec.tv_sec = waittime / NANOSECS_PER_SEC;
2007 waitspec.tv_nsec = waittime % NANOSECS_PER_SEC;
2008 }
2009
2010 kr = semaphore_timedwait(_semaphore, waitspec);
2011 }
2012
2013 return kr == KERN_SUCCESS;
2014 }
2015
2016 #else
2017
2018 bool Semaphore::trywait() {
2019 return sem_trywait(&_semaphore) == 0;
2020 }
2021
2022 bool Semaphore::timedwait(unsigned int sec, int nsec) {
2023 struct timespec ts;
2024 unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec);
2025
2026 while (1) {
2027 int result = sem_timedwait(&_semaphore, &ts);
2028 if (result == 0) {
2029 return true;
2030 } else if (errno == EINTR) {
2031 continue;
2032 } else if (errno == ETIMEDOUT) {
2033 return false;
2034 } else {
2035 return false;
2036 }
2037 }
2038 }
2039
2040 #endif // __APPLE__
2041
2042 static os_semaphore_t sig_sem;
2043 static Semaphore sr_semaphore;
2044
2045 void os::signal_init_pd() {
2046 // Initialize signal structures
2047 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
2048
2049 // Initialize signal semaphore
2050 ::SEM_INIT(sig_sem, 0);
2051 }
2052
2053 void os::signal_notify(int sig) {
2054 Atomic::inc(&pending_signals[sig]);
2055 ::SEM_POST(sig_sem);
2056 }
2057
2058 static int check_pending_signals(bool wait) {
2059 Atomic::store(0, &sigint_count);
2060 for (;;) {
2061 for (int i = 0; i < NSIG + 1; i++) {
2062 jint n = pending_signals[i];
2063 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
2064 return i;
2065 }
2066 }
2067 if (!wait) {
2068 return -1;
2069 }
2070 JavaThread *thread = JavaThread::current();
2071 ThreadBlockInVM tbivm(thread);
2072
2073 bool threadIsSuspended;
2074 do {
2075 thread->set_suspend_equivalent();
2076 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
2077 ::SEM_WAIT(sig_sem);
2078
2079 // were we externally suspended while we were waiting?
2080 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
2081 if (threadIsSuspended) {
2082 //
2083 // The semaphore has been incremented, but while we were waiting
2084 // another thread suspended us. We don't want to continue running
2085 // while suspended because that would surprise the thread that
2086 // suspended us.
2087 //
2088 ::SEM_POST(sig_sem);
2089
2090 thread->java_suspend_self();
2091 }
2092 } while (threadIsSuspended);
2093 }
2094 }
2095
2096 int os::signal_lookup() {
2097 return check_pending_signals(false);
2098 }
2099
2100 int os::signal_wait() {
2101 return check_pending_signals(true);
2102 }
2103
2104 ////////////////////////////////////////////////////////////////////////////////
2105 // Virtual Memory
2106
2107 int os::vm_page_size() {
2108 // Seems redundant as all get out
2109 assert(os::Bsd::page_size() != -1, "must call os::init");
2110 return os::Bsd::page_size();
2111 }
2112
2113 // Solaris allocates memory by pages.
2114 int os::vm_allocation_granularity() {
2115 assert(os::Bsd::page_size() != -1, "must call os::init");
2116 return os::Bsd::page_size();
2117 }
2118
2119 // Rationale behind this function:
2120 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
2121 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
2122 // samples for JITted code. Here we create private executable mapping over the code cache
2123 // and then we can use standard (well, almost, as mapping can change) way to provide
2124 // info for the reporting script by storing timestamp and location of symbol
2125 void bsd_wrap_code(char* base, size_t size) {
2126 static volatile jint cnt = 0;
2127
2128 if (!UseOprofile) {
2129 return;
2130 }
2131
2132 char buf[PATH_MAX + 1];
2133 int num = Atomic::add(1, &cnt);
2134
2135 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
2136 os::get_temp_directory(), os::current_process_id(), num);
2137 unlink(buf);
2138
2139 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
2140
2141 if (fd != -1) {
2142 off_t rv = ::lseek(fd, size-2, SEEK_SET);
2143 if (rv != (off_t)-1) {
2144 if (::write(fd, "", 1) == 1) {
2145 mmap(base, size,
2146 PROT_READ|PROT_WRITE|PROT_EXEC,
2147 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
2148 }
2149 }
2150 ::close(fd);
2151 unlink(buf);
2152 }
2153 }
2154
2155 static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
2156 int err) {
2157 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT
2158 ", %d) failed; error='%s' (errno=%d)", addr, size, exec,
2159 strerror(err), err);
2160 }
2161
2162 // NOTE: Bsd kernel does not really reserve the pages for us.
2163 // All it does is to check if there are enough free pages
2164 // left at the time of mmap(). This could be a potential
2165 // problem.
2166 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
2167 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
2168 #ifdef __OpenBSD__
2169 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2170 if (::mprotect(addr, size, prot) == 0) {
2171 return true;
2172 }
2173 #else
2174 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
2175 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
2176 if (res != (uintptr_t) MAP_FAILED) {
2177 return true;
2178 }
2179 #endif
2180
2181 // Warn about any commit errors we see in non-product builds just
2182 // in case mmap() doesn't work as described on the man page.
2183 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);)
2184
2185 return false;
2186 }
2187
2188 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
2189 bool exec) {
2190 // alignment_hint is ignored on this OS
2191 return pd_commit_memory(addr, size, exec);
2192 }
2193
2194 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
2195 const char* mesg) {
2196 assert(mesg != NULL, "mesg must be specified");
2197 if (!pd_commit_memory(addr, size, exec)) {
2198 // add extra info in product mode for vm_exit_out_of_memory():
2199 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
2200 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, mesg);
2201 }
2202 }
2203
2204 void os::pd_commit_memory_or_exit(char* addr, size_t size,
2205 size_t alignment_hint, bool exec,
2206 const char* mesg) {
2207 // alignment_hint is ignored on this OS
2208 pd_commit_memory_or_exit(addr, size, exec, mesg);
2209 }
2210
2211 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
2212 }
2213
2214 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
2215 ::madvise(addr, bytes, MADV_DONTNEED);
2216 }
2217
2218 void os::numa_make_global(char *addr, size_t bytes) {
2219 }
2220
2221 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
2222 }
2223
2224 bool os::numa_topology_changed() { return false; }
2225
2226 size_t os::numa_get_groups_num() {
2227 return 1;
2228 }
2229
2230 int os::numa_get_group_id() {
2231 return 0;
2232 }
2233
2234 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
2235 if (size > 0) {
2236 ids[0] = 0;
2237 return 1;
2238 }
2239 return 0;
2240 }
2241
2242 bool os::get_page_info(char *start, page_info* info) {
2243 return false;
2244 }
2245
2246 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2247 return end;
2248 }
2249
2250
2251 bool os::pd_uncommit_memory(char* addr, size_t size) {
2252 #ifdef __OpenBSD__
2253 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2254 return ::mprotect(addr, size, PROT_NONE) == 0;
2255 #else
2256 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
2257 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
2258 return res != (uintptr_t) MAP_FAILED;
2259 #endif
2260 }
2261
2262 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2263 return os::commit_memory(addr, size, !ExecMem);
2264 }
2265
2266 // If this is a growable mapping, remove the guard pages entirely by
2267 // munmap()ping them. If not, just call uncommit_memory().
2268 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2269 return os::uncommit_memory(addr, size);
2270 }
2271
2272 static address _highest_vm_reserved_address = NULL;
2273
2274 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2275 // at 'requested_addr'. If there are existing memory mappings at the same
2276 // location, however, they will be overwritten. If 'fixed' is false,
2277 // 'requested_addr' is only treated as a hint, the return value may or
2278 // may not start from the requested address. Unlike Bsd mmap(), this
2279 // function returns NULL to indicate failure.
2280 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2281 char * addr;
2282 int flags;
2283
2284 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2285 if (fixed) {
2286 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2287 flags |= MAP_FIXED;
2288 }
2289
2290 // Map reserved/uncommitted pages PROT_NONE so we fail early if we
2291 // touch an uncommitted page. Otherwise, the read/write might
2292 // succeed if we have enough swap space to back the physical page.
2293 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE,
2294 flags, -1, 0);
2295
2296 if (addr != MAP_FAILED) {
2297 // anon_mmap() should only get called during VM initialization,
2298 // don't need lock (actually we can skip locking even it can be called
2299 // from multiple threads, because _highest_vm_reserved_address is just a
2300 // hint about the upper limit of non-stack memory regions.)
2301 if ((address)addr + bytes > _highest_vm_reserved_address) {
2302 _highest_vm_reserved_address = (address)addr + bytes;
2303 }
2304 }
2305
2306 return addr == MAP_FAILED ? NULL : addr;
2307 }
2308
2309 // Don't update _highest_vm_reserved_address, because there might be memory
2310 // regions above addr + size. If so, releasing a memory region only creates
2311 // a hole in the address space, it doesn't help prevent heap-stack collision.
2312 //
2313 static int anon_munmap(char * addr, size_t size) {
2314 return ::munmap(addr, size) == 0;
2315 }
2316
2317 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
2318 size_t alignment_hint) {
2319 return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2320 }
2321
2322 bool os::pd_release_memory(char* addr, size_t size) {
2323 return anon_munmap(addr, size);
2324 }
2325
2326 static bool bsd_mprotect(char* addr, size_t size, int prot) {
2327 // Bsd wants the mprotect address argument to be page aligned.
2328 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size());
2329
2330 // According to SUSv3, mprotect() should only be used with mappings
2331 // established by mmap(), and mmap() always maps whole pages. Unaligned
2332 // 'addr' likely indicates problem in the VM (e.g. trying to change
2333 // protection of malloc'ed or statically allocated memory). Check the
2334 // caller if you hit this assert.
2335 assert(addr == bottom, "sanity check");
2336
2337 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2338 return ::mprotect(bottom, size, prot) == 0;
2339 }
2340
2341 // Set protections specified
2342 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2343 bool is_committed) {
2344 unsigned int p = 0;
2345 switch (prot) {
2346 case MEM_PROT_NONE: p = PROT_NONE; break;
2347 case MEM_PROT_READ: p = PROT_READ; break;
2348 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
2349 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2350 default:
2351 ShouldNotReachHere();
2352 }
2353 // is_committed is unused.
2354 return bsd_mprotect(addr, bytes, p);
2355 }
2356
2357 bool os::guard_memory(char* addr, size_t size) {
2358 return bsd_mprotect(addr, size, PROT_NONE);
2359 }
2360
2361 bool os::unguard_memory(char* addr, size_t size) {
2362 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
2363 }
2364
2365 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
2366 return false;
2367 }
2368
2369 // Large page support
2370
2371 static size_t _large_page_size = 0;
2372
2373 void os::large_page_init() {
2374 }
2375
2376
2377 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) {
2378 fatal("This code is not used or maintained.");
2379
2380 // "exec" is passed in but not used. Creating the shared image for
2381 // the code cache doesn't have an SHM_X executable permission to check.
2382 assert(UseLargePages && UseSHM, "only for SHM large pages");
2383
2384 key_t key = IPC_PRIVATE;
2385 char *addr;
2386
2387 bool warn_on_failure = UseLargePages &&
2388 (!FLAG_IS_DEFAULT(UseLargePages) ||
2389 !FLAG_IS_DEFAULT(LargePageSizeInBytes)
2390 );
2391 char msg[128];
2392
2393 // Create a large shared memory region to attach to based on size.
2394 // Currently, size is the total size of the heap
2395 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W);
2396 if (shmid == -1) {
2397 // Possible reasons for shmget failure:
2398 // 1. shmmax is too small for Java heap.
2399 // > check shmmax value: cat /proc/sys/kernel/shmmax
2400 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax
2401 // 2. not enough large page memory.
2402 // > check available large pages: cat /proc/meminfo
2403 // > increase amount of large pages:
2404 // echo new_value > /proc/sys/vm/nr_hugepages
2405 // Note 1: different Bsd may use different name for this property,
2406 // e.g. on Redhat AS-3 it is "hugetlb_pool".
2407 // Note 2: it's possible there's enough physical memory available but
2408 // they are so fragmented after a long run that they can't
2409 // coalesce into large pages. Try to reserve large pages when
2410 // the system is still "fresh".
2411 if (warn_on_failure) {
2412 jio_snprintf(msg, sizeof(msg), "Failed to reserve shared memory (errno = %d).", errno);
2413 warning(msg);
2414 }
2415 return NULL;
2416 }
2417
2418 // attach to the region
2419 addr = (char*)shmat(shmid, req_addr, 0);
2420 int err = errno;
2421
2422 // Remove shmid. If shmat() is successful, the actual shared memory segment
2423 // will be deleted when it's detached by shmdt() or when the process
2424 // terminates. If shmat() is not successful this will remove the shared
2425 // segment immediately.
2426 shmctl(shmid, IPC_RMID, NULL);
2427
2428 if ((intptr_t)addr == -1) {
2429 if (warn_on_failure) {
2430 jio_snprintf(msg, sizeof(msg), "Failed to attach shared memory (errno = %d).", err);
2431 warning(msg);
2432 }
2433 return NULL;
2434 }
2435
2436 // The memory is committed
2437 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, mtNone, CALLER_PC);
2438
2439 return addr;
2440 }
2441
2442 bool os::release_memory_special(char* base, size_t bytes) {
2443 MemTracker::Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
2444 // detaching the SHM segment will also delete it, see reserve_memory_special()
2445 int rslt = shmdt(base);
2446 if (rslt == 0) {
2447 tkr.record((address)base, bytes);
2448 return true;
2449 } else {
2450 tkr.discard();
2451 return false;
2452 }
2453
2454 }
2455
2456 size_t os::large_page_size() {
2457 return _large_page_size;
2458 }
2459
2460 // HugeTLBFS allows application to commit large page memory on demand;
2461 // with SysV SHM the entire memory region must be allocated as shared
2462 // memory.
2463 bool os::can_commit_large_page_memory() {
2464 return UseHugeTLBFS;
2465 }
2466
2467 bool os::can_execute_large_page_memory() {
2468 return UseHugeTLBFS;
2469 }
2470
2471 // Reserve memory at an arbitrary address, only if that area is
2472 // available (and not reserved for something else).
2473
2474 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2475 const int max_tries = 10;
2476 char* base[max_tries];
2477 size_t size[max_tries];
2478 const size_t gap = 0x000000;
2479
2480 // Assert only that the size is a multiple of the page size, since
2481 // that's all that mmap requires, and since that's all we really know
2482 // about at this low abstraction level. If we need higher alignment,
2483 // we can either pass an alignment to this method or verify alignment
2484 // in one of the methods further up the call chain. See bug 5044738.
2485 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2486
2487 // Repeatedly allocate blocks until the block is allocated at the
2488 // right spot. Give up after max_tries. Note that reserve_memory() will
2489 // automatically update _highest_vm_reserved_address if the call is
2490 // successful. The variable tracks the highest memory address every reserved
2491 // by JVM. It is used to detect heap-stack collision if running with
2492 // fixed-stack BsdThreads. Because here we may attempt to reserve more
2493 // space than needed, it could confuse the collision detecting code. To
2494 // solve the problem, save current _highest_vm_reserved_address and
2495 // calculate the correct value before return.
2496 address old_highest = _highest_vm_reserved_address;
2497
2498 // Bsd mmap allows caller to pass an address as hint; give it a try first,
2499 // if kernel honors the hint then we can return immediately.
2500 char * addr = anon_mmap(requested_addr, bytes, false);
2501 if (addr == requested_addr) {
2502 return requested_addr;
2503 }
2504
2505 if (addr != NULL) {
2506 // mmap() is successful but it fails to reserve at the requested address
2507 anon_munmap(addr, bytes);
2508 }
2509
2510 int i;
2511 for (i = 0; i < max_tries; ++i) {
2512 base[i] = reserve_memory(bytes);
2513
2514 if (base[i] != NULL) {
2515 // Is this the block we wanted?
2516 if (base[i] == requested_addr) {
2517 size[i] = bytes;
2518 break;
2519 }
2520
2521 // Does this overlap the block we wanted? Give back the overlapped
2522 // parts and try again.
2523
2524 size_t top_overlap = requested_addr + (bytes + gap) - base[i];
2525 if (top_overlap >= 0 && top_overlap < bytes) {
2526 unmap_memory(base[i], top_overlap);
2527 base[i] += top_overlap;
2528 size[i] = bytes - top_overlap;
2529 } else {
2530 size_t bottom_overlap = base[i] + bytes - requested_addr;
2531 if (bottom_overlap >= 0 && bottom_overlap < bytes) {
2532 unmap_memory(requested_addr, bottom_overlap);
2533 size[i] = bytes - bottom_overlap;
2534 } else {
2535 size[i] = bytes;
2536 }
2537 }
2538 }
2539 }
2540
2541 // Give back the unused reserved pieces.
2542
2543 for (int j = 0; j < i; ++j) {
2544 if (base[j] != NULL) {
2545 unmap_memory(base[j], size[j]);
2546 }
2547 }
2548
2549 if (i < max_tries) {
2550 _highest_vm_reserved_address = MAX2(old_highest, (address)requested_addr + bytes);
2551 return requested_addr;
2552 } else {
2553 _highest_vm_reserved_address = old_highest;
2554 return NULL;
2555 }
2556 }
2557
2558 size_t os::read(int fd, void *buf, unsigned int nBytes) {
2559 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes));
2560 }
2561
2562 void os::naked_short_sleep(jlong ms) {
2563 struct timespec req;
2564
2565 assert(ms < 1000, "Un-interruptable sleep, short time use only");
2566 req.tv_sec = 0;
2567 if (ms > 0) {
2568 req.tv_nsec = (ms % 1000) * 1000000;
2569 }
2570 else {
2571 req.tv_nsec = 1;
2572 }
2573
2574 nanosleep(&req, NULL);
2575
2576 return;
2577 }
2578
2579 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2580 void os::infinite_sleep() {
2581 while (true) { // sleep forever ...
2582 ::sleep(100); // ... 100 seconds at a time
2583 }
2584 }
2585
2586 // Used to convert frequent JVM_Yield() to nops
2587 bool os::dont_yield() {
2588 return DontYieldALot;
2589 }
2590
2591 void os::yield() {
2592 sched_yield();
2593 }
2594
2595 os::YieldResult os::NakedYield() { sched_yield(); return os::YIELD_UNKNOWN ;}
2596
2597 void os::yield_all(int attempts) {
2598 // Yields to all threads, including threads with lower priorities
2599 // Threads on Bsd are all with same priority. The Solaris style
2600 // os::yield_all() with nanosleep(1ms) is not necessary.
2601 sched_yield();
2602 }
2603
2604 // Called from the tight loops to possibly influence time-sharing heuristics
2605 void os::loop_breaker(int attempts) {
2606 os::yield_all(attempts);
2607 }
2608
2609 ////////////////////////////////////////////////////////////////////////////////
2610 // thread priority support
2611
2612 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2613 // only supports dynamic priority, static priority must be zero. For real-time
2614 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
2615 // However, for large multi-threaded applications, SCHED_RR is not only slower
2616 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2617 // of 5 runs - Sep 2005).
2618 //
2619 // The following code actually changes the niceness of kernel-thread/LWP. It
2620 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
2621 // not the entire user process, and user level threads are 1:1 mapped to kernel
2622 // threads. It has always been the case, but could change in the future. For
2623 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2624 // It is only used when ThreadPriorityPolicy=1 and requires root privilege.
2625
2626 #if !defined(__APPLE__)
2627 int os::java_to_os_priority[CriticalPriority + 1] = {
2628 19, // 0 Entry should never be used
2629
2630 0, // 1 MinPriority
2631 3, // 2
2632 6, // 3
2633
2634 10, // 4
2635 15, // 5 NormPriority
2636 18, // 6
2637
2638 21, // 7
2639 25, // 8
2640 28, // 9 NearMaxPriority
2641
2642 31, // 10 MaxPriority
2643
2644 31 // 11 CriticalPriority
2645 };
2646 #else
2647 /* Using Mach high-level priority assignments */
2648 int os::java_to_os_priority[CriticalPriority + 1] = {
2649 0, // 0 Entry should never be used (MINPRI_USER)
2650
2651 27, // 1 MinPriority
2652 28, // 2
2653 29, // 3
2654
2655 30, // 4
2656 31, // 5 NormPriority (BASEPRI_DEFAULT)
2657 32, // 6
2658
2659 33, // 7
2660 34, // 8
2661 35, // 9 NearMaxPriority
2662
2663 36, // 10 MaxPriority
2664
2665 36 // 11 CriticalPriority
2666 };
2667 #endif
2668
2669 static int prio_init() {
2670 if (ThreadPriorityPolicy == 1) {
2671 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1
2672 // if effective uid is not root. Perhaps, a more elegant way of doing
2673 // this is to test CAP_SYS_NICE capability, but that will require libcap.so
2674 if (geteuid() != 0) {
2675 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
2676 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd");
2677 }
2678 ThreadPriorityPolicy = 0;
2679 }
2680 }
2681 if (UseCriticalJavaThreadPriority) {
2682 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2683 }
2684 return 0;
2685 }
2686
2687 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2688 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) return OS_OK;
2689
2690 #ifdef __OpenBSD__
2691 // OpenBSD pthread_setprio starves low priority threads
2692 return OS_OK;
2693 #elif defined(__FreeBSD__)
2694 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2695 #elif defined(__APPLE__) || defined(__NetBSD__)
2696 struct sched_param sp;
2697 int policy;
2698 pthread_t self = pthread_self();
2699
2700 if (pthread_getschedparam(self, &policy, &sp) != 0)
2701 return OS_ERR;
2702
2703 sp.sched_priority = newpri;
2704 if (pthread_setschedparam(self, policy, &sp) != 0)
2705 return OS_ERR;
2706
2707 return OS_OK;
2708 #else
2709 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2710 return (ret == 0) ? OS_OK : OS_ERR;
2711 #endif
2712 }
2713
2714 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2715 if ( !UseThreadPriorities || ThreadPriorityPolicy == 0 ) {
2716 *priority_ptr = java_to_os_priority[NormPriority];
2717 return OS_OK;
2718 }
2719
2720 errno = 0;
2721 #if defined(__OpenBSD__) || defined(__FreeBSD__)
2722 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2723 #elif defined(__APPLE__) || defined(__NetBSD__)
2724 int policy;
2725 struct sched_param sp;
2726
2727 pthread_getschedparam(pthread_self(), &policy, &sp);
2728 *priority_ptr = sp.sched_priority;
2729 #else
2730 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2731 #endif
2732 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2733 }
2734
2735 // Hint to the underlying OS that a task switch would not be good.
2736 // Void return because it's a hint and can fail.
2737 void os::hint_no_preempt() {}
2738
2739 ////////////////////////////////////////////////////////////////////////////////
2740 // suspend/resume support
2741
2742 // the low-level signal-based suspend/resume support is a remnant from the
2743 // old VM-suspension that used to be for java-suspension, safepoints etc,
2744 // within hotspot. Now there is a single use-case for this:
2745 // - calling get_thread_pc() on the VMThread by the flat-profiler task
2746 // that runs in the watcher thread.
2747 // The remaining code is greatly simplified from the more general suspension
2748 // code that used to be used.
2749 //
2750 // The protocol is quite simple:
2751 // - suspend:
2752 // - sends a signal to the target thread
2753 // - polls the suspend state of the osthread using a yield loop
2754 // - target thread signal handler (SR_handler) sets suspend state
2755 // and blocks in sigsuspend until continued
2756 // - resume:
2757 // - sets target osthread state to continue
2758 // - sends signal to end the sigsuspend loop in the SR_handler
2759 //
2760 // Note that the SR_lock plays no role in this suspend/resume protocol.
2761 //
2762
2763 static void resume_clear_context(OSThread *osthread) {
2764 osthread->set_ucontext(NULL);
2765 osthread->set_siginfo(NULL);
2766 }
2767
2768 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2769 osthread->set_ucontext(context);
2770 osthread->set_siginfo(siginfo);
2771 }
2772
2773 //
2774 // Handler function invoked when a thread's execution is suspended or
2775 // resumed. We have to be careful that only async-safe functions are
2776 // called here (Note: most pthread functions are not async safe and
2777 // should be avoided.)
2778 //
2779 // Note: sigwait() is a more natural fit than sigsuspend() from an
2780 // interface point of view, but sigwait() prevents the signal hander
2781 // from being run. libpthread would get very confused by not having
2782 // its signal handlers run and prevents sigwait()'s use with the
2783 // mutex granting granting signal.
2784 //
2785 // Currently only ever called on the VMThread or JavaThread
2786 //
2787 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2788 // Save and restore errno to avoid confusing native code with EINTR
2789 // after sigsuspend.
2790 int old_errno = errno;
2791
2792 Thread* thread = Thread::current();
2793 OSThread* osthread = thread->osthread();
2794 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
2795
2796 os::SuspendResume::State current = osthread->sr.state();
2797 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
2798 suspend_save_context(osthread, siginfo, context);
2799
2800 // attempt to switch the state, we assume we had a SUSPEND_REQUEST
2801 os::SuspendResume::State state = osthread->sr.suspended();
2802 if (state == os::SuspendResume::SR_SUSPENDED) {
2803 sigset_t suspend_set; // signals for sigsuspend()
2804
2805 // get current set of blocked signals and unblock resume signal
2806 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2807 sigdelset(&suspend_set, SR_signum);
2808
2809 sr_semaphore.signal();
2810 // wait here until we are resumed
2811 while (1) {
2812 sigsuspend(&suspend_set);
2813
2814 os::SuspendResume::State result = osthread->sr.running();
2815 if (result == os::SuspendResume::SR_RUNNING) {
2816 sr_semaphore.signal();
2817 break;
2818 } else if (result != os::SuspendResume::SR_SUSPENDED) {
2819 ShouldNotReachHere();
2820 }
2821 }
2822
2823 } else if (state == os::SuspendResume::SR_RUNNING) {
2824 // request was cancelled, continue
2825 } else {
2826 ShouldNotReachHere();
2827 }
2828
2829 resume_clear_context(osthread);
2830 } else if (current == os::SuspendResume::SR_RUNNING) {
2831 // request was cancelled, continue
2832 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
2833 // ignore
2834 } else {
2835 // ignore
2836 }
2837
2838 errno = old_errno;
2839 }
2840
2841
2842 static int SR_initialize() {
2843 struct sigaction act;
2844 char *s;
2845 /* Get signal number to use for suspend/resume */
2846 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2847 int sig = ::strtol(s, 0, 10);
2848 if (sig > 0 || sig < NSIG) {
2849 SR_signum = sig;
2850 }
2851 }
2852
2853 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2854 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2855
2856 sigemptyset(&SR_sigset);
2857 sigaddset(&SR_sigset, SR_signum);
2858
2859 /* Set up signal handler for suspend/resume */
2860 act.sa_flags = SA_RESTART|SA_SIGINFO;
2861 act.sa_handler = (void (*)(int)) SR_handler;
2862
2863 // SR_signum is blocked by default.
2864 // 4528190 - We also need to block pthread restart signal (32 on all
2865 // supported Bsd platforms). Note that BsdThreads need to block
2866 // this signal for all threads to work properly. So we don't have
2867 // to use hard-coded signal number when setting up the mask.
2868 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2869
2870 if (sigaction(SR_signum, &act, 0) == -1) {
2871 return -1;
2872 }
2873
2874 // Save signal flag
2875 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2876 return 0;
2877 }
2878
2879 static int sr_notify(OSThread* osthread) {
2880 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2881 assert_status(status == 0, status, "pthread_kill");
2882 return status;
2883 }
2884
2885 // "Randomly" selected value for how long we want to spin
2886 // before bailing out on suspending a thread, also how often
2887 // we send a signal to a thread we want to resume
2888 static const int RANDOMLY_LARGE_INTEGER = 1000000;
2889 static const int RANDOMLY_LARGE_INTEGER2 = 100;
2890
2891 // returns true on success and false on error - really an error is fatal
2892 // but this seems the normal response to library errors
2893 static bool do_suspend(OSThread* osthread) {
2894 assert(osthread->sr.is_running(), "thread should be running");
2895 assert(!sr_semaphore.trywait(), "semaphore has invalid state");
2896
2897 // mark as suspended and send signal
2898 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
2899 // failed to switch, state wasn't running?
2900 ShouldNotReachHere();
2901 return false;
2902 }
2903
2904 if (sr_notify(osthread) != 0) {
2905 ShouldNotReachHere();
2906 }
2907
2908 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
2909 while (true) {
2910 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2911 break;
2912 } else {
2913 // timeout
2914 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
2915 if (cancelled == os::SuspendResume::SR_RUNNING) {
2916 return false;
2917 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
2918 // make sure that we consume the signal on the semaphore as well
2919 sr_semaphore.wait();
2920 break;
2921 } else {
2922 ShouldNotReachHere();
2923 return false;
2924 }
2925 }
2926 }
2927
2928 guarantee(osthread->sr.is_suspended(), "Must be suspended");
2929 return true;
2930 }
2931
2932 static void do_resume(OSThread* osthread) {
2933 assert(osthread->sr.is_suspended(), "thread should be suspended");
2934 assert(!sr_semaphore.trywait(), "invalid semaphore state");
2935
2936 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
2937 // failed to switch to WAKEUP_REQUEST
2938 ShouldNotReachHere();
2939 return;
2940 }
2941
2942 while (true) {
2943 if (sr_notify(osthread) == 0) {
2944 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2945 if (osthread->sr.is_running()) {
2946 return;
2947 }
2948 }
2949 } else {
2950 ShouldNotReachHere();
2951 }
2952 }
2953
2954 guarantee(osthread->sr.is_running(), "Must be running!");
2955 }
2956
2957 ///////////////////////////////////////////////////////////////////////////////////
2958 // signal handling (except suspend/resume)
2959
2960 // This routine may be used by user applications as a "hook" to catch signals.
2961 // The user-defined signal handler must pass unrecognized signals to this
2962 // routine, and if it returns true (non-zero), then the signal handler must
2963 // return immediately. If the flag "abort_if_unrecognized" is true, then this
2964 // routine will never retun false (zero), but instead will execute a VM panic
2965 // routine kill the process.
2966 //
2967 // If this routine returns false, it is OK to call it again. This allows
2968 // the user-defined signal handler to perform checks either before or after
2969 // the VM performs its own checks. Naturally, the user code would be making
2970 // a serious error if it tried to handle an exception (such as a null check
2971 // or breakpoint) that the VM was generating for its own correct operation.
2972 //
2973 // This routine may recognize any of the following kinds of signals:
2974 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
2975 // It should be consulted by handlers for any of those signals.
2976 //
2977 // The caller of this routine must pass in the three arguments supplied
2978 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
2979 // field of the structure passed to sigaction(). This routine assumes that
2980 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
2981 //
2982 // Note that the VM will print warnings if it detects conflicting signal
2983 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
2984 //
2985 extern "C" JNIEXPORT int
2986 JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
2987 void* ucontext, int abort_if_unrecognized);
2988
2989 void signalHandler(int sig, siginfo_t* info, void* uc) {
2990 assert(info != NULL && uc != NULL, "it must be old kernel");
2991 int orig_errno = errno; // Preserve errno value over signal handler.
2992 JVM_handle_bsd_signal(sig, info, uc, true);
2993 errno = orig_errno;
2994 }
2995
2996
2997 // This boolean allows users to forward their own non-matching signals
2998 // to JVM_handle_bsd_signal, harmlessly.
2999 bool os::Bsd::signal_handlers_are_installed = false;
3000
3001 // For signal-chaining
3002 struct sigaction os::Bsd::sigact[MAXSIGNUM];
3003 unsigned int os::Bsd::sigs = 0;
3004 bool os::Bsd::libjsig_is_loaded = false;
3005 typedef struct sigaction *(*get_signal_t)(int);
3006 get_signal_t os::Bsd::get_signal_action = NULL;
3007
3008 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
3009 struct sigaction *actp = NULL;
3010
3011 if (libjsig_is_loaded) {
3012 // Retrieve the old signal handler from libjsig
3013 actp = (*get_signal_action)(sig);
3014 }
3015 if (actp == NULL) {
3016 // Retrieve the preinstalled signal handler from jvm
3017 actp = get_preinstalled_handler(sig);
3018 }
3019
3020 return actp;
3021 }
3022
3023 static bool call_chained_handler(struct sigaction *actp, int sig,
3024 siginfo_t *siginfo, void *context) {
3025 // Call the old signal handler
3026 if (actp->sa_handler == SIG_DFL) {
3027 // It's more reasonable to let jvm treat it as an unexpected exception
3028 // instead of taking the default action.
3029 return false;
3030 } else if (actp->sa_handler != SIG_IGN) {
3031 if ((actp->sa_flags & SA_NODEFER) == 0) {
3032 // automaticlly block the signal
3033 sigaddset(&(actp->sa_mask), sig);
3034 }
3035
3036 sa_handler_t hand;
3037 sa_sigaction_t sa;
3038 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
3039 // retrieve the chained handler
3040 if (siginfo_flag_set) {
3041 sa = actp->sa_sigaction;
3042 } else {
3043 hand = actp->sa_handler;
3044 }
3045
3046 if ((actp->sa_flags & SA_RESETHAND) != 0) {
3047 actp->sa_handler = SIG_DFL;
3048 }
3049
3050 // try to honor the signal mask
3051 sigset_t oset;
3052 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
3053
3054 // call into the chained handler
3055 if (siginfo_flag_set) {
3056 (*sa)(sig, siginfo, context);
3057 } else {
3058 (*hand)(sig);
3059 }
3060
3061 // restore the signal mask
3062 pthread_sigmask(SIG_SETMASK, &oset, 0);
3063 }
3064 // Tell jvm's signal handler the signal is taken care of.
3065 return true;
3066 }
3067
3068 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
3069 bool chained = false;
3070 // signal-chaining
3071 if (UseSignalChaining) {
3072 struct sigaction *actp = get_chained_signal_action(sig);
3073 if (actp != NULL) {
3074 chained = call_chained_handler(actp, sig, siginfo, context);
3075 }
3076 }
3077 return chained;
3078 }
3079
3080 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) {
3081 if ((( (unsigned int)1 << sig ) & sigs) != 0) {
3082 return &sigact[sig];
3083 }
3084 return NULL;
3085 }
3086
3087 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
3088 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3089 sigact[sig] = oldAct;
3090 sigs |= (unsigned int)1 << sig;
3091 }
3092
3093 // for diagnostic
3094 int os::Bsd::sigflags[MAXSIGNUM];
3095
3096 int os::Bsd::get_our_sigflags(int sig) {
3097 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3098 return sigflags[sig];
3099 }
3100
3101 void os::Bsd::set_our_sigflags(int sig, int flags) {
3102 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3103 sigflags[sig] = flags;
3104 }
3105
3106 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
3107 // Check for overwrite.
3108 struct sigaction oldAct;
3109 sigaction(sig, (struct sigaction*)NULL, &oldAct);
3110
3111 void* oldhand = oldAct.sa_sigaction
3112 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3113 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3114 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
3115 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
3116 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
3117 if (AllowUserSignalHandlers || !set_installed) {
3118 // Do not overwrite; user takes responsibility to forward to us.
3119 return;
3120 } else if (UseSignalChaining) {
3121 // save the old handler in jvm
3122 save_preinstalled_handler(sig, oldAct);
3123 // libjsig also interposes the sigaction() call below and saves the
3124 // old sigaction on it own.
3125 } else {
3126 fatal(err_msg("Encountered unexpected pre-existing sigaction handler "
3127 "%#lx for signal %d.", (long)oldhand, sig));
3128 }
3129 }
3130
3131 struct sigaction sigAct;
3132 sigfillset(&(sigAct.sa_mask));
3133 sigAct.sa_handler = SIG_DFL;
3134 if (!set_installed) {
3135 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3136 } else {
3137 sigAct.sa_sigaction = signalHandler;
3138 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3139 }
3140 #if __APPLE__
3141 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV
3142 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages"
3143 // if the signal handler declares it will handle it on alternate stack.
3144 // Notice we only declare we will handle it on alt stack, but we are not
3145 // actually going to use real alt stack - this is just a workaround.
3146 // Please see ux_exception.c, method catch_mach_exception_raise for details
3147 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c
3148 if (sig == SIGSEGV) {
3149 sigAct.sa_flags |= SA_ONSTACK;
3150 }
3151 #endif
3152
3153 // Save flags, which are set by ours
3154 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3155 sigflags[sig] = sigAct.sa_flags;
3156
3157 int ret = sigaction(sig, &sigAct, &oldAct);
3158 assert(ret == 0, "check");
3159
3160 void* oldhand2 = oldAct.sa_sigaction
3161 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3162 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3163 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
3164 }
3165
3166 // install signal handlers for signals that HotSpot needs to
3167 // handle in order to support Java-level exception handling.
3168
3169 void os::Bsd::install_signal_handlers() {
3170 if (!signal_handlers_are_installed) {
3171 signal_handlers_are_installed = true;
3172
3173 // signal-chaining
3174 typedef void (*signal_setting_t)();
3175 signal_setting_t begin_signal_setting = NULL;
3176 signal_setting_t end_signal_setting = NULL;
3177 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3178 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
3179 if (begin_signal_setting != NULL) {
3180 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3181 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
3182 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
3183 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
3184 libjsig_is_loaded = true;
3185 assert(UseSignalChaining, "should enable signal-chaining");
3186 }
3187 if (libjsig_is_loaded) {
3188 // Tell libjsig jvm is setting signal handlers
3189 (*begin_signal_setting)();
3190 }
3191
3192 set_signal_handler(SIGSEGV, true);
3193 set_signal_handler(SIGPIPE, true);
3194 set_signal_handler(SIGBUS, true);
3195 set_signal_handler(SIGILL, true);
3196 set_signal_handler(SIGFPE, true);
3197 set_signal_handler(SIGXFSZ, true);
3198
3199 #if defined(__APPLE__)
3200 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
3201 // signals caught and handled by the JVM. To work around this, we reset the mach task
3202 // signal handler that's placed on our process by CrashReporter. This disables
3203 // CrashReporter-based reporting.
3204 //
3205 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
3206 // on caught fatal signals.
3207 //
3208 // Additionally, gdb installs both standard BSD signal handlers, and mach exception
3209 // handlers. By replacing the existing task exception handler, we disable gdb's mach
3210 // exception handling, while leaving the standard BSD signal handlers functional.
3211 kern_return_t kr;
3212 kr = task_set_exception_ports(mach_task_self(),
3213 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
3214 MACH_PORT_NULL,
3215 EXCEPTION_STATE_IDENTITY,
3216 MACHINE_THREAD_STATE);
3217
3218 assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
3219 #endif
3220
3221 if (libjsig_is_loaded) {
3222 // Tell libjsig jvm finishes setting signal handlers
3223 (*end_signal_setting)();
3224 }
3225
3226 // We don't activate signal checker if libjsig is in place, we trust ourselves
3227 // and if UserSignalHandler is installed all bets are off
3228 if (CheckJNICalls) {
3229 if (libjsig_is_loaded) {
3230 if (PrintJNIResolving) {
3231 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
3232 }
3233 check_signals = false;
3234 }
3235 if (AllowUserSignalHandlers) {
3236 if (PrintJNIResolving) {
3237 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
3238 }
3239 check_signals = false;
3240 }
3241 }
3242 }
3243 }
3244
3245
3246 /////
3247 // glibc on Bsd platform uses non-documented flag
3248 // to indicate, that some special sort of signal
3249 // trampoline is used.
3250 // We will never set this flag, and we should
3251 // ignore this flag in our diagnostic
3252 #ifdef SIGNIFICANT_SIGNAL_MASK
3253 #undef SIGNIFICANT_SIGNAL_MASK
3254 #endif
3255 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
3256
3257 static const char* get_signal_handler_name(address handler,
3258 char* buf, int buflen) {
3259 int offset;
3260 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
3261 if (found) {
3262 // skip directory names
3263 const char *p1, *p2;
3264 p1 = buf;
3265 size_t len = strlen(os::file_separator());
3266 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
3267 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
3268 } else {
3269 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
3270 }
3271 return buf;
3272 }
3273
3274 static void print_signal_handler(outputStream* st, int sig,
3275 char* buf, size_t buflen) {
3276 struct sigaction sa;
3277
3278 sigaction(sig, NULL, &sa);
3279
3280 // See comment for SIGNIFICANT_SIGNAL_MASK define
3281 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3282
3283 st->print("%s: ", os::exception_name(sig, buf, buflen));
3284
3285 address handler = (sa.sa_flags & SA_SIGINFO)
3286 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
3287 : CAST_FROM_FN_PTR(address, sa.sa_handler);
3288
3289 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
3290 st->print("SIG_DFL");
3291 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
3292 st->print("SIG_IGN");
3293 } else {
3294 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
3295 }
3296
3297 st->print(", sa_mask[0]=" PTR32_FORMAT, *(uint32_t*)&sa.sa_mask);
3298
3299 address rh = VMError::get_resetted_sighandler(sig);
3300 // May be, handler was resetted by VMError?
3301 if(rh != NULL) {
3302 handler = rh;
3303 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
3304 }
3305
3306 st->print(", sa_flags=" PTR32_FORMAT, sa.sa_flags);
3307
3308 // Check: is it our handler?
3309 if(handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
3310 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
3311 // It is our signal handler
3312 // check for flags, reset system-used one!
3313 if((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3314 st->print(
3315 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
3316 os::Bsd::get_our_sigflags(sig));
3317 }
3318 }
3319 st->cr();
3320 }
3321
3322
3323 #define DO_SIGNAL_CHECK(sig) \
3324 if (!sigismember(&check_signal_done, sig)) \
3325 os::Bsd::check_signal_handler(sig)
3326
3327 // This method is a periodic task to check for misbehaving JNI applications
3328 // under CheckJNI, we can add any periodic checks here
3329
3330 void os::run_periodic_checks() {
3331
3332 if (check_signals == false) return;
3333
3334 // SEGV and BUS if overridden could potentially prevent
3335 // generation of hs*.log in the event of a crash, debugging
3336 // such a case can be very challenging, so we absolutely
3337 // check the following for a good measure:
3338 DO_SIGNAL_CHECK(SIGSEGV);
3339 DO_SIGNAL_CHECK(SIGILL);
3340 DO_SIGNAL_CHECK(SIGFPE);
3341 DO_SIGNAL_CHECK(SIGBUS);
3342 DO_SIGNAL_CHECK(SIGPIPE);
3343 DO_SIGNAL_CHECK(SIGXFSZ);
3344
3345
3346 // ReduceSignalUsage allows the user to override these handlers
3347 // see comments at the very top and jvm_solaris.h
3348 if (!ReduceSignalUsage) {
3349 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
3350 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
3351 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
3352 DO_SIGNAL_CHECK(BREAK_SIGNAL);
3353 }
3354
3355 DO_SIGNAL_CHECK(SR_signum);
3356 DO_SIGNAL_CHECK(INTERRUPT_SIGNAL);
3357 }
3358
3359 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
3360
3361 static os_sigaction_t os_sigaction = NULL;
3362
3363 void os::Bsd::check_signal_handler(int sig) {
3364 char buf[O_BUFLEN];
3365 address jvmHandler = NULL;
3366
3367
3368 struct sigaction act;
3369 if (os_sigaction == NULL) {
3370 // only trust the default sigaction, in case it has been interposed
3371 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
3372 if (os_sigaction == NULL) return;
3373 }
3374
3375 os_sigaction(sig, (struct sigaction*)NULL, &act);
3376
3377
3378 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3379
3380 address thisHandler = (act.sa_flags & SA_SIGINFO)
3381 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3382 : CAST_FROM_FN_PTR(address, act.sa_handler) ;
3383
3384
3385 switch(sig) {
3386 case SIGSEGV:
3387 case SIGBUS:
3388 case SIGFPE:
3389 case SIGPIPE:
3390 case SIGILL:
3391 case SIGXFSZ:
3392 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
3393 break;
3394
3395 case SHUTDOWN1_SIGNAL:
3396 case SHUTDOWN2_SIGNAL:
3397 case SHUTDOWN3_SIGNAL:
3398 case BREAK_SIGNAL:
3399 jvmHandler = (address)user_handler();
3400 break;
3401
3402 case INTERRUPT_SIGNAL:
3403 jvmHandler = CAST_FROM_FN_PTR(address, SIG_DFL);
3404 break;
3405
3406 default:
3407 if (sig == SR_signum) {
3408 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3409 } else {
3410 return;
3411 }
3412 break;
3413 }
3414
3415 if (thisHandler != jvmHandler) {
3416 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3417 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3418 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3419 // No need to check this sig any longer
3420 sigaddset(&check_signal_done, sig);
3421 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3422 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3423 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig));
3424 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags);
3425 // No need to check this sig any longer
3426 sigaddset(&check_signal_done, sig);
3427 }
3428
3429 // Dump all the signal
3430 if (sigismember(&check_signal_done, sig)) {
3431 print_signal_handlers(tty, buf, O_BUFLEN);
3432 }
3433 }
3434
3435 extern void report_error(char* file_name, int line_no, char* title, char* format, ...);
3436
3437 extern bool signal_name(int signo, char* buf, size_t len);
3438
3439 const char* os::exception_name(int exception_code, char* buf, size_t size) {
3440 if (0 < exception_code && exception_code <= SIGRTMAX) {
3441 // signal
3442 if (!signal_name(exception_code, buf, size)) {
3443 jio_snprintf(buf, size, "SIG%d", exception_code);
3444 }
3445 return buf;
3446 } else {
3447 return NULL;
3448 }
3449 }
3450
3451 // this is called _before_ the most of global arguments have been parsed
3452 void os::init(void) {
3453 char dummy; /* used to get a guess on initial stack address */
3454 // first_hrtime = gethrtime();
3455
3456 // With BsdThreads the JavaMain thread pid (primordial thread)
3457 // is different than the pid of the java launcher thread.
3458 // So, on Bsd, the launcher thread pid is passed to the VM
3459 // via the sun.java.launcher.pid property.
3460 // Use this property instead of getpid() if it was correctly passed.
3461 // See bug 6351349.
3462 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid();
3463
3464 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid();
3465
3466 clock_tics_per_sec = CLK_TCK;
3467
3468 init_random(1234567);
3469
3470 ThreadCritical::initialize();
3471
3472 Bsd::set_page_size(getpagesize());
3473 if (Bsd::page_size() == -1) {
3474 fatal(err_msg("os_bsd.cpp: os::init: sysconf failed (%s)",
3475 strerror(errno)));
3476 }
3477 init_page_sizes((size_t) Bsd::page_size());
3478
3479 Bsd::initialize_system_info();
3480
3481 // main_thread points to the aboriginal thread
3482 Bsd::_main_thread = pthread_self();
3483
3484 Bsd::clock_init();
3485 initial_time_count = javaTimeNanos();
3486
3487 #ifdef __APPLE__
3488 // XXXDARWIN
3489 // Work around the unaligned VM callbacks in hotspot's
3490 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on
3491 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces
3492 // alignment when doing symbol lookup. To work around this, we force early
3493 // binding of all symbols now, thus binding when alignment is known-good.
3494 _dyld_bind_fully_image_containing_address((const void *) &os::init);
3495 #endif
3496 }
3497
3498 // To install functions for atexit system call
3499 extern "C" {
3500 static void perfMemory_exit_helper() {
3501 perfMemory_exit();
3502 }
3503 }
3504
3505 // this is called _after_ the global arguments have been parsed
3506 jint os::init_2(void)
3507 {
3508 // Allocate a single page and mark it as readable for safepoint polling
3509 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3510 guarantee( polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page" );
3511
3512 os::set_polling_page( polling_page );
3513
3514 #ifndef PRODUCT
3515 if(Verbose && PrintMiscellaneous)
3516 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n", (intptr_t)polling_page);
3517 #endif
3518
3519 if (!UseMembar) {
3520 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3521 guarantee( mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page");
3522 os::set_memory_serialize_page( mem_serialize_page );
3523
3524 #ifndef PRODUCT
3525 if(Verbose && PrintMiscellaneous)
3526 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n", (intptr_t)mem_serialize_page);
3527 #endif
3528 }
3529
3530 // initialize suspend/resume support - must do this before signal_sets_init()
3531 if (SR_initialize() != 0) {
3532 perror("SR_initialize failed");
3533 return JNI_ERR;
3534 }
3535
3536 Bsd::signal_sets_init();
3537 Bsd::install_signal_handlers();
3538
3539 // Check minimum allowable stack size for thread creation and to initialize
3540 // the java system classes, including StackOverflowError - depends on page
3541 // size. Add a page for compiler2 recursion in main thread.
3542 // Add in 2*BytesPerWord times page size to account for VM stack during
3543 // class initialization depending on 32 or 64 bit VM.
3544 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed,
3545 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+
3546 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size());
3547
3548 size_t threadStackSizeInBytes = ThreadStackSize * K;
3549 if (threadStackSizeInBytes != 0 &&
3550 threadStackSizeInBytes < os::Bsd::min_stack_allowed) {
3551 tty->print_cr("\nThe stack size specified is too small, "
3552 "Specify at least %dk",
3553 os::Bsd::min_stack_allowed/ K);
3554 return JNI_ERR;
3555 }
3556
3557 // Make the stack size a multiple of the page size so that
3558 // the yellow/red zones can be guarded.
3559 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes,
3560 vm_page_size()));
3561
3562 if (MaxFDLimit) {
3563 // set the number of file descriptors to max. print out error
3564 // if getrlimit/setrlimit fails but continue regardless.
3565 struct rlimit nbr_files;
3566 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3567 if (status != 0) {
3568 if (PrintMiscellaneous && (Verbose || WizardMode))
3569 perror("os::init_2 getrlimit failed");
3570 } else {
3571 nbr_files.rlim_cur = nbr_files.rlim_max;
3572
3573 #ifdef __APPLE__
3574 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3575 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3576 // be used instead
3577 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3578 #endif
3579
3580 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3581 if (status != 0) {
3582 if (PrintMiscellaneous && (Verbose || WizardMode))
3583 perror("os::init_2 setrlimit failed");
3584 }
3585 }
3586 }
3587
3588 // at-exit methods are called in the reverse order of their registration.
3589 // atexit functions are called on return from main or as a result of a
3590 // call to exit(3C). There can be only 32 of these functions registered
3591 // and atexit() does not set errno.
3592
3593 if (PerfAllowAtExitRegistration) {
3594 // only register atexit functions if PerfAllowAtExitRegistration is set.
3595 // atexit functions can be delayed until process exit time, which
3596 // can be problematic for embedded VM situations. Embedded VMs should
3597 // call DestroyJavaVM() to assure that VM resources are released.
3598
3599 // note: perfMemory_exit_helper atexit function may be removed in
3600 // the future if the appropriate cleanup code can be added to the
3601 // VM_Exit VMOperation's doit method.
3602 if (atexit(perfMemory_exit_helper) != 0) {
3603 warning("os::init2 atexit(perfMemory_exit_helper) failed");
3604 }
3605 }
3606
3607 // initialize thread priority policy
3608 prio_init();
3609
3610 #ifdef __APPLE__
3611 // dynamically link to objective c gc registration
3612 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3613 if (handleLibObjc != NULL) {
3614 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3615 }
3616 #endif
3617
3618 return JNI_OK;
3619 }
3620
3621 // this is called at the end of vm_initialization
3622 void os::init_3(void) { }
3623
3624 // Mark the polling page as unreadable
3625 void os::make_polling_page_unreadable(void) {
3626 if( !guard_memory((char*)_polling_page, Bsd::page_size()) )
3627 fatal("Could not disable polling page");
3628 };
3629
3630 // Mark the polling page as readable
3631 void os::make_polling_page_readable(void) {
3632 if( !bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
3633 fatal("Could not enable polling page");
3634 }
3635 };
3636
3637 int os::active_processor_count() {
3638 return _processor_count;
3639 }
3640
3641 void os::set_native_thread_name(const char *name) {
3642 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3643 // This is only supported in Snow Leopard and beyond
3644 if (name != NULL) {
3645 // Add a "Java: " prefix to the name
3646 char buf[MAXTHREADNAMESIZE];
3647 snprintf(buf, sizeof(buf), "Java: %s", name);
3648 pthread_setname_np(buf);
3649 }
3650 #endif
3651 }
3652
3653 bool os::distribute_processes(uint length, uint* distribution) {
3654 // Not yet implemented.
3655 return false;
3656 }
3657
3658 bool os::bind_to_processor(uint processor_id) {
3659 // Not yet implemented.
3660 return false;
3661 }
3662
3663 void os::SuspendedThreadTask::internal_do_task() {
3664 if (do_suspend(_thread->osthread())) {
3665 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
3666 do_task(context);
3667 do_resume(_thread->osthread());
3668 }
3669 }
3670
3671 ///
3672 class PcFetcher : public os::SuspendedThreadTask {
3673 public:
3674 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {}
3675 ExtendedPC result();
3676 protected:
3677 void do_task(const os::SuspendedThreadTaskContext& context);
3678 private:
3679 ExtendedPC _epc;
3680 };
3681
3682 ExtendedPC PcFetcher::result() {
3683 guarantee(is_done(), "task is not done yet.");
3684 return _epc;
3685 }
3686
3687 void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) {
3688 Thread* thread = context.thread();
3689 OSThread* osthread = thread->osthread();
3690 if (osthread->ucontext() != NULL) {
3691 _epc = os::Bsd::ucontext_get_pc((ucontext_t *) context.ucontext());
3692 } else {
3693 // NULL context is unexpected, double-check this is the VMThread
3694 guarantee(thread->is_VM_thread(), "can only be called for VMThread");
3695 }
3696 }
3697
3698 // Suspends the target using the signal mechanism and then grabs the PC before
3699 // resuming the target. Used by the flat-profiler only
3700 ExtendedPC os::get_thread_pc(Thread* thread) {
3701 // Make sure that it is called by the watcher for the VMThread
3702 assert(Thread::current()->is_Watcher_thread(), "Must be watcher");
3703 assert(thread->is_VM_thread(), "Can only be called for VMThread");
3704
3705 PcFetcher fetcher(thread);
3706 fetcher.run();
3707 return fetcher.result();
3708 }
3709
3710 int os::Bsd::safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime)
3711 {
3712 return pthread_cond_timedwait(_cond, _mutex, _abstime);
3713 }
3714
3715 ////////////////////////////////////////////////////////////////////////////////
3716 // debug support
3717
3718 bool os::find(address addr, outputStream* st) {
3719 Dl_info dlinfo;
3720 memset(&dlinfo, 0, sizeof(dlinfo));
3721 if (dladdr(addr, &dlinfo) != 0) {
3722 st->print(PTR_FORMAT ": ", addr);
3723 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) {
3724 st->print("%s+%#x", dlinfo.dli_sname,
3725 addr - (intptr_t)dlinfo.dli_saddr);
3726 } else if (dlinfo.dli_fbase != NULL) {
3727 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase);
3728 } else {
3729 st->print("<absolute address>");
3730 }
3731 if (dlinfo.dli_fname != NULL) {
3732 st->print(" in %s", dlinfo.dli_fname);
3733 }
3734 if (dlinfo.dli_fbase != NULL) {
3735 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase);
3736 }
3737 st->cr();
3738
3739 if (Verbose) {
3740 // decode some bytes around the PC
3741 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
3742 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size());
3743 address lowest = (address) dlinfo.dli_sname;
3744 if (!lowest) lowest = (address) dlinfo.dli_fbase;
3745 if (begin < lowest) begin = lowest;
3746 Dl_info dlinfo2;
3747 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr
3748 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin)
3749 end = (address) dlinfo2.dli_saddr;
3750 Disassembler::decode(begin, end, st);
3751 }
3752 return true;
3753 }
3754 return false;
3755 }
3756
3757 ////////////////////////////////////////////////////////////////////////////////
3758 // misc
3759
3760 // This does not do anything on Bsd. This is basically a hook for being
3761 // able to use structured exception handling (thread-local exception filters)
3762 // on, e.g., Win32.
3763 void
3764 os::os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method,
3765 JavaCallArguments* args, Thread* thread) {
3766 f(value, method, args, thread);
3767 }
3768
3769 void os::print_statistics() {
3770 }
3771
3772 int os::message_box(const char* title, const char* message) {
3773 int i;
3774 fdStream err(defaultStream::error_fd());
3775 for (i = 0; i < 78; i++) err.print_raw("=");
3776 err.cr();
3777 err.print_raw_cr(title);
3778 for (i = 0; i < 78; i++) err.print_raw("-");
3779 err.cr();
3780 err.print_raw_cr(message);
3781 for (i = 0; i < 78; i++) err.print_raw("=");
3782 err.cr();
3783
3784 char buf[16];
3785 // Prevent process from exiting upon "read error" without consuming all CPU
3786 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3787
3788 return buf[0] == 'y' || buf[0] == 'Y';
3789 }
3790
3791 int os::stat(const char *path, struct stat *sbuf) {
3792 char pathbuf[MAX_PATH];
3793 if (strlen(path) > MAX_PATH - 1) {
3794 errno = ENAMETOOLONG;
3795 return -1;
3796 }
3797 os::native_path(strcpy(pathbuf, path));
3798 return ::stat(pathbuf, sbuf);
3799 }
3800
3801 bool os::check_heap(bool force) {
3802 return true;
3803 }
3804
3805 int local_vsnprintf(char* buf, size_t count, const char* format, va_list args) {
3806 return ::vsnprintf(buf, count, format, args);
3807 }
3808
3809 // Is a (classpath) directory empty?
3810 bool os::dir_is_empty(const char* path) {
3811 DIR *dir = NULL;
3812 struct dirent *ptr;
3813
3814 dir = opendir(path);
3815 if (dir == NULL) return true;
3816
3817 /* Scan the directory */
3818 bool result = true;
3819 char buf[sizeof(struct dirent) + MAX_PATH];
3820 while (result && (ptr = ::readdir(dir)) != NULL) {
3821 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3822 result = false;
3823 }
3824 }
3825 closedir(dir);
3826 return result;
3827 }
3828
3829 // This code originates from JDK's sysOpen and open64_w
3830 // from src/solaris/hpi/src/system_md.c
3831
3832 #ifndef O_DELETE
3833 #define O_DELETE 0x10000
3834 #endif
3835
3836 // Open a file. Unlink the file immediately after open returns
3837 // if the specified oflag has the O_DELETE flag set.
3838 // O_DELETE is used only in j2se/src/share/native/java/util/zip/ZipFile.c
3839
3840 int os::open(const char *path, int oflag, int mode) {
3841
3842 if (strlen(path) > MAX_PATH - 1) {
3843 errno = ENAMETOOLONG;
3844 return -1;
3845 }
3846 int fd;
3847 int o_delete = (oflag & O_DELETE);
3848 oflag = oflag & ~O_DELETE;
3849
3850 fd = ::open(path, oflag, mode);
3851 if (fd == -1) return -1;
3852
3853 //If the open succeeded, the file might still be a directory
3854 {
3855 struct stat buf;
3856 int ret = ::fstat(fd, &buf);
3857 int st_mode = buf.st_mode;
3858
3859 if (ret != -1) {
3860 if ((st_mode & S_IFMT) == S_IFDIR) {
3861 errno = EISDIR;
3862 ::close(fd);
3863 return -1;
3864 }
3865 } else {
3866 ::close(fd);
3867 return -1;
3868 }
3869 }
3870
3871 /*
3872 * All file descriptors that are opened in the JVM and not
3873 * specifically destined for a subprocess should have the
3874 * close-on-exec flag set. If we don't set it, then careless 3rd
3875 * party native code might fork and exec without closing all
3876 * appropriate file descriptors (e.g. as we do in closeDescriptors in
3877 * UNIXProcess.c), and this in turn might:
3878 *
3879 * - cause end-of-file to fail to be detected on some file
3880 * descriptors, resulting in mysterious hangs, or
3881 *
3882 * - might cause an fopen in the subprocess to fail on a system
3883 * suffering from bug 1085341.
3884 *
3885 * (Yes, the default setting of the close-on-exec flag is a Unix
3886 * design flaw)
3887 *
3888 * See:
3889 * 1085341: 32-bit stdio routines should support file descriptors >255
3890 * 4843136: (process) pipe file descriptor from Runtime.exec not being closed
3891 * 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
3892 */
3893 #ifdef FD_CLOEXEC
3894 {
3895 int flags = ::fcntl(fd, F_GETFD);
3896 if (flags != -1)
3897 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
3898 }
3899 #endif
3900
3901 if (o_delete != 0) {
3902 ::unlink(path);
3903 }
3904 return fd;
3905 }
3906
3907
3908 // create binary file, rewriting existing file if required
3909 int os::create_binary_file(const char* path, bool rewrite_existing) {
3910 int oflags = O_WRONLY | O_CREAT;
3911 if (!rewrite_existing) {
3912 oflags |= O_EXCL;
3913 }
3914 return ::open(path, oflags, S_IREAD | S_IWRITE);
3915 }
3916
3917 // return current position of file pointer
3918 jlong os::current_file_offset(int fd) {
3919 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
3920 }
3921
3922 // move file pointer to the specified offset
3923 jlong os::seek_to_file_offset(int fd, jlong offset) {
3924 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
3925 }
3926
3927 // This code originates from JDK's sysAvailable
3928 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
3929
3930 int os::available(int fd, jlong *bytes) {
3931 jlong cur, end;
3932 int mode;
3933 struct stat buf;
3934
3935 if (::fstat(fd, &buf) >= 0) {
3936 mode = buf.st_mode;
3937 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
3938 /*
3939 * XXX: is the following call interruptible? If so, this might
3940 * need to go through the INTERRUPT_IO() wrapper as for other
3941 * blocking, interruptible calls in this file.
3942 */
3943 int n;
3944 if (::ioctl(fd, FIONREAD, &n) >= 0) {
3945 *bytes = n;
3946 return 1;
3947 }
3948 }
3949 }
3950 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
3951 return 0;
3952 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
3953 return 0;
3954 } else if (::lseek(fd, cur, SEEK_SET) == -1) {
3955 return 0;
3956 }
3957 *bytes = end - cur;
3958 return 1;
3959 }
3960
3961 int os::socket_available(int fd, jint *pbytes) {
3962 if (fd < 0)
3963 return OS_OK;
3964
3965 int ret;
3966
3967 RESTARTABLE(::ioctl(fd, FIONREAD, pbytes), ret);
3968
3969 //%% note ioctl can return 0 when successful, JVM_SocketAvailable
3970 // is expected to return 0 on failure and 1 on success to the jdk.
3971
3972 return (ret == OS_ERR) ? 0 : 1;
3973 }
3974
3975 // Map a block of memory.
3976 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
3977 char *addr, size_t bytes, bool read_only,
3978 bool allow_exec) {
3979 int prot;
3980 int flags;
3981
3982 if (read_only) {
3983 prot = PROT_READ;
3984 flags = MAP_SHARED;
3985 } else {
3986 prot = PROT_READ | PROT_WRITE;
3987 flags = MAP_PRIVATE;
3988 }
3989
3990 if (allow_exec) {
3991 prot |= PROT_EXEC;
3992 }
3993
3994 if (addr != NULL) {
3995 flags |= MAP_FIXED;
3996 }
3997
3998 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
3999 fd, file_offset);
4000 if (mapped_address == MAP_FAILED) {
4001 return NULL;
4002 }
4003 return mapped_address;
4004 }
4005
4006
4007 // Remap a block of memory.
4008 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
4009 char *addr, size_t bytes, bool read_only,
4010 bool allow_exec) {
4011 // same as map_memory() on this OS
4012 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
4013 allow_exec);
4014 }
4015
4016
4017 // Unmap a block of memory.
4018 bool os::pd_unmap_memory(char* addr, size_t bytes) {
4019 return munmap(addr, bytes) == 0;
4020 }
4021
4022 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
4023 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
4024 // of a thread.
4025 //
4026 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
4027 // the fast estimate available on the platform.
4028
4029 jlong os::current_thread_cpu_time() {
4030 #ifdef __APPLE__
4031 return os::thread_cpu_time(Thread::current(), true /* user + sys */);
4032 #else
4033 Unimplemented();
4034 return 0;
4035 #endif
4036 }
4037
4038 jlong os::thread_cpu_time(Thread* thread) {
4039 #ifdef __APPLE__
4040 return os::thread_cpu_time(thread, true /* user + sys */);
4041 #else
4042 Unimplemented();
4043 return 0;
4044 #endif
4045 }
4046
4047 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
4048 #ifdef __APPLE__
4049 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
4050 #else
4051 Unimplemented();
4052 return 0;
4053 #endif
4054 }
4055
4056 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
4057 #ifdef __APPLE__
4058 struct thread_basic_info tinfo;
4059 mach_msg_type_number_t tcount = THREAD_INFO_MAX;
4060 kern_return_t kr;
4061 thread_t mach_thread;
4062
4063 mach_thread = thread->osthread()->thread_id();
4064 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
4065 if (kr != KERN_SUCCESS)
4066 return -1;
4067
4068 if (user_sys_cpu_time) {
4069 jlong nanos;
4070 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
4071 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
4072 return nanos;
4073 } else {
4074 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
4075 }
4076 #else
4077 Unimplemented();
4078 return 0;
4079 #endif
4080 }
4081
4082
4083 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4084 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4085 info_ptr->may_skip_backward = false; // elapsed time not wall time
4086 info_ptr->may_skip_forward = false; // elapsed time not wall time
4087 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4088 }
4089
4090 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4091 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4092 info_ptr->may_skip_backward = false; // elapsed time not wall time
4093 info_ptr->may_skip_forward = false; // elapsed time not wall time
4094 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4095 }
4096
4097 bool os::is_thread_cpu_time_supported() {
4098 #ifdef __APPLE__
4099 return true;
4100 #else
4101 return false;
4102 #endif
4103 }
4104
4105 // System loadavg support. Returns -1 if load average cannot be obtained.
4106 // Bsd doesn't yet have a (official) notion of processor sets,
4107 // so just return the system wide load average.
4108 int os::loadavg(double loadavg[], int nelem) {
4109 return ::getloadavg(loadavg, nelem);
4110 }
4111
4112 void os::pause() {
4113 char filename[MAX_PATH];
4114 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
4115 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
4116 } else {
4117 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
4118 }
4119
4120 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
4121 if (fd != -1) {
4122 struct stat buf;
4123 ::close(fd);
4124 while (::stat(filename, &buf) == 0) {
4125 (void)::poll(NULL, 0, 100);
4126 }
4127 } else {
4128 jio_fprintf(stderr,
4129 "Could not open pause file '%s', continuing immediately.\n", filename);
4130 }
4131 }
4132
4133
4134 // Refer to the comments in os_solaris.cpp park-unpark.
4135 //
4136 // Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can
4137 // hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable.
4138 // For specifics regarding the bug see GLIBC BUGID 261237 :
4139 // http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html.
4140 // Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future
4141 // will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar
4142 // is used. (The simple C test-case provided in the GLIBC bug report manifests the
4143 // hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos()
4144 // and monitorenter when we're using 1-0 locking. All those operations may result in
4145 // calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version
4146 // of libpthread avoids the problem, but isn't practical.
4147 //
4148 // Possible remedies:
4149 //
4150 // 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work.
4151 // This is palliative and probabilistic, however. If the thread is preempted
4152 // between the call to compute_abstime() and pthread_cond_timedwait(), more
4153 // than the minimum period may have passed, and the abstime may be stale (in the
4154 // past) resultin in a hang. Using this technique reduces the odds of a hang
4155 // but the JVM is still vulnerable, particularly on heavily loaded systems.
4156 //
4157 // 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead
4158 // of the usual flag-condvar-mutex idiom. The write side of the pipe is set
4159 // NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo)
4160 // reduces to poll()+read(). This works well, but consumes 2 FDs per extant
4161 // thread.
4162 //
4163 // 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread
4164 // that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing
4165 // a timeout request to the chron thread and then blocking via pthread_cond_wait().
4166 // This also works well. In fact it avoids kernel-level scalability impediments
4167 // on certain platforms that don't handle lots of active pthread_cond_timedwait()
4168 // timers in a graceful fashion.
4169 //
4170 // 4. When the abstime value is in the past it appears that control returns
4171 // correctly from pthread_cond_timedwait(), but the condvar is left corrupt.
4172 // Subsequent timedwait/wait calls may hang indefinitely. Given that, we
4173 // can avoid the problem by reinitializing the condvar -- by cond_destroy()
4174 // followed by cond_init() -- after all calls to pthread_cond_timedwait().
4175 // It may be possible to avoid reinitialization by checking the return
4176 // value from pthread_cond_timedwait(). In addition to reinitializing the
4177 // condvar we must establish the invariant that cond_signal() is only called
4178 // within critical sections protected by the adjunct mutex. This prevents
4179 // cond_signal() from "seeing" a condvar that's in the midst of being
4180 // reinitialized or that is corrupt. Sadly, this invariant obviates the
4181 // desirable signal-after-unlock optimization that avoids futile context switching.
4182 //
4183 // I'm also concerned that some versions of NTPL might allocate an auxilliary
4184 // structure when a condvar is used or initialized. cond_destroy() would
4185 // release the helper structure. Our reinitialize-after-timedwait fix
4186 // put excessive stress on malloc/free and locks protecting the c-heap.
4187 //
4188 // We currently use (4). See the WorkAroundNTPLTimedWaitHang flag.
4189 // It may be possible to refine (4) by checking the kernel and NTPL verisons
4190 // and only enabling the work-around for vulnerable environments.
4191
4192 // utility to compute the abstime argument to timedwait:
4193 // millis is the relative timeout time
4194 // abstime will be the absolute timeout time
4195 // TODO: replace compute_abstime() with unpackTime()
4196
4197 static struct timespec* compute_abstime(struct timespec* abstime, jlong millis) {
4198 if (millis < 0) millis = 0;
4199 struct timeval now;
4200 int status = gettimeofday(&now, NULL);
4201 assert(status == 0, "gettimeofday");
4202 jlong seconds = millis / 1000;
4203 millis %= 1000;
4204 if (seconds > 50000000) { // see man cond_timedwait(3T)
4205 seconds = 50000000;
4206 }
4207 abstime->tv_sec = now.tv_sec + seconds;
4208 long usec = now.tv_usec + millis * 1000;
4209 if (usec >= 1000000) {
4210 abstime->tv_sec += 1;
4211 usec -= 1000000;
4212 }
4213 abstime->tv_nsec = usec * 1000;
4214 return abstime;
4215 }
4216
4217
4218 // Test-and-clear _Event, always leaves _Event set to 0, returns immediately.
4219 // Conceptually TryPark() should be equivalent to park(0).
4220
4221 int os::PlatformEvent::TryPark() {
4222 for (;;) {
4223 const int v = _Event ;
4224 guarantee ((v == 0) || (v == 1), "invariant") ;
4225 if (Atomic::cmpxchg (0, &_Event, v) == v) return v ;
4226 }
4227 }
4228
4229 void os::PlatformEvent::park() { // AKA "down()"
4230 // Invariant: Only the thread associated with the Event/PlatformEvent
4231 // may call park().
4232 // TODO: assert that _Assoc != NULL or _Assoc == Self
4233 int v ;
4234 for (;;) {
4235 v = _Event ;
4236 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4237 }
4238 guarantee (v >= 0, "invariant") ;
4239 if (v == 0) {
4240 // Do this the hard way by blocking ...
4241 int status = pthread_mutex_lock(_mutex);
4242 assert_status(status == 0, status, "mutex_lock");
4243 guarantee (_nParked == 0, "invariant") ;
4244 ++ _nParked ;
4245 while (_Event < 0) {
4246 status = pthread_cond_wait(_cond, _mutex);
4247 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ...
4248 // Treat this the same as if the wait was interrupted
4249 if (status == ETIMEDOUT) { status = EINTR; }
4250 assert_status(status == 0 || status == EINTR, status, "cond_wait");
4251 }
4252 -- _nParked ;
4253
4254 _Event = 0 ;
4255 status = pthread_mutex_unlock(_mutex);
4256 assert_status(status == 0, status, "mutex_unlock");
4257 // Paranoia to ensure our locked and lock-free paths interact
4258 // correctly with each other.
4259 OrderAccess::fence();
4260 }
4261 guarantee (_Event >= 0, "invariant") ;
4262 }
4263
4264 int os::PlatformEvent::park(jlong millis) {
4265 guarantee (_nParked == 0, "invariant") ;
4266
4267 int v ;
4268 for (;;) {
4269 v = _Event ;
4270 if (Atomic::cmpxchg (v-1, &_Event, v) == v) break ;
4271 }
4272 guarantee (v >= 0, "invariant") ;
4273 if (v != 0) return OS_OK ;
4274
4275 // We do this the hard way, by blocking the thread.
4276 // Consider enforcing a minimum timeout value.
4277 struct timespec abst;
4278 compute_abstime(&abst, millis);
4279
4280 int ret = OS_TIMEOUT;
4281 int status = pthread_mutex_lock(_mutex);
4282 assert_status(status == 0, status, "mutex_lock");
4283 guarantee (_nParked == 0, "invariant") ;
4284 ++_nParked ;
4285
4286 // Object.wait(timo) will return because of
4287 // (a) notification
4288 // (b) timeout
4289 // (c) thread.interrupt
4290 //
4291 // Thread.interrupt and object.notify{All} both call Event::set.
4292 // That is, we treat thread.interrupt as a special case of notification.
4293 // The underlying Solaris implementation, cond_timedwait, admits
4294 // spurious/premature wakeups, but the JLS/JVM spec prevents the
4295 // JVM from making those visible to Java code. As such, we must
4296 // filter out spurious wakeups. We assume all ETIME returns are valid.
4297 //
4298 // TODO: properly differentiate simultaneous notify+interrupt.
4299 // In that case, we should propagate the notify to another waiter.
4300
4301 while (_Event < 0) {
4302 status = os::Bsd::safe_cond_timedwait(_cond, _mutex, &abst);
4303 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4304 pthread_cond_destroy (_cond);
4305 pthread_cond_init (_cond, NULL) ;
4306 }
4307 assert_status(status == 0 || status == EINTR ||
4308 status == ETIMEDOUT,
4309 status, "cond_timedwait");
4310 if (!FilterSpuriousWakeups) break ; // previous semantics
4311 if (status == ETIMEDOUT) break ;
4312 // We consume and ignore EINTR and spurious wakeups.
4313 }
4314 --_nParked ;
4315 if (_Event >= 0) {
4316 ret = OS_OK;
4317 }
4318 _Event = 0 ;
4319 status = pthread_mutex_unlock(_mutex);
4320 assert_status(status == 0, status, "mutex_unlock");
4321 assert (_nParked == 0, "invariant") ;
4322 // Paranoia to ensure our locked and lock-free paths interact
4323 // correctly with each other.
4324 OrderAccess::fence();
4325 return ret;
4326 }
4327
4328 void os::PlatformEvent::unpark() {
4329 // Transitions for _Event:
4330 // 0 :=> 1
4331 // 1 :=> 1
4332 // -1 :=> either 0 or 1; must signal target thread
4333 // That is, we can safely transition _Event from -1 to either
4334 // 0 or 1. Forcing 1 is slightly more efficient for back-to-back
4335 // unpark() calls.
4336 // See also: "Semaphores in Plan 9" by Mullender & Cox
4337 //
4338 // Note: Forcing a transition from "-1" to "1" on an unpark() means
4339 // that it will take two back-to-back park() calls for the owning
4340 // thread to block. This has the benefit of forcing a spurious return
4341 // from the first park() call after an unpark() call which will help
4342 // shake out uses of park() and unpark() without condition variables.
4343
4344 if (Atomic::xchg(1, &_Event) >= 0) return;
4345
4346 // Wait for the thread associated with the event to vacate
4347 int status = pthread_mutex_lock(_mutex);
4348 assert_status(status == 0, status, "mutex_lock");
4349 int AnyWaiters = _nParked;
4350 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant");
4351 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) {
4352 AnyWaiters = 0;
4353 pthread_cond_signal(_cond);
4354 }
4355 status = pthread_mutex_unlock(_mutex);
4356 assert_status(status == 0, status, "mutex_unlock");
4357 if (AnyWaiters != 0) {
4358 status = pthread_cond_signal(_cond);
4359 assert_status(status == 0, status, "cond_signal");
4360 }
4361
4362 // Note that we signal() _after dropping the lock for "immortal" Events.
4363 // This is safe and avoids a common class of futile wakeups. In rare
4364 // circumstances this can cause a thread to return prematurely from
4365 // cond_{timed}wait() but the spurious wakeup is benign and the victim will
4366 // simply re-test the condition and re-park itself.
4367 }
4368
4369
4370 // JSR166
4371 // -------------------------------------------------------
4372
4373 /*
4374 * The solaris and bsd implementations of park/unpark are fairly
4375 * conservative for now, but can be improved. They currently use a
4376 * mutex/condvar pair, plus a a count.
4377 * Park decrements count if > 0, else does a condvar wait. Unpark
4378 * sets count to 1 and signals condvar. Only one thread ever waits
4379 * on the condvar. Contention seen when trying to park implies that someone
4380 * is unparking you, so don't wait. And spurious returns are fine, so there
4381 * is no need to track notifications.
4382 */
4383
4384 #define MAX_SECS 100000000
4385 /*
4386 * This code is common to bsd and solaris and will be moved to a
4387 * common place in dolphin.
4388 *
4389 * The passed in time value is either a relative time in nanoseconds
4390 * or an absolute time in milliseconds. Either way it has to be unpacked
4391 * into suitable seconds and nanoseconds components and stored in the
4392 * given timespec structure.
4393 * Given time is a 64-bit value and the time_t used in the timespec is only
4394 * a signed-32-bit value (except on 64-bit Bsd) we have to watch for
4395 * overflow if times way in the future are given. Further on Solaris versions
4396 * prior to 10 there is a restriction (see cond_timedwait) that the specified
4397 * number of seconds, in abstime, is less than current_time + 100,000,000.
4398 * As it will be 28 years before "now + 100000000" will overflow we can
4399 * ignore overflow and just impose a hard-limit on seconds using the value
4400 * of "now + 100,000,000". This places a limit on the timeout of about 3.17
4401 * years from "now".
4402 */
4403
4404 static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) {
4405 assert (time > 0, "convertTime");
4406
4407 struct timeval now;
4408 int status = gettimeofday(&now, NULL);
4409 assert(status == 0, "gettimeofday");
4410
4411 time_t max_secs = now.tv_sec + MAX_SECS;
4412
4413 if (isAbsolute) {
4414 jlong secs = time / 1000;
4415 if (secs > max_secs) {
4416 absTime->tv_sec = max_secs;
4417 }
4418 else {
4419 absTime->tv_sec = secs;
4420 }
4421 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC;
4422 }
4423 else {
4424 jlong secs = time / NANOSECS_PER_SEC;
4425 if (secs >= MAX_SECS) {
4426 absTime->tv_sec = max_secs;
4427 absTime->tv_nsec = 0;
4428 }
4429 else {
4430 absTime->tv_sec = now.tv_sec + secs;
4431 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000;
4432 if (absTime->tv_nsec >= NANOSECS_PER_SEC) {
4433 absTime->tv_nsec -= NANOSECS_PER_SEC;
4434 ++absTime->tv_sec; // note: this must be <= max_secs
4435 }
4436 }
4437 }
4438 assert(absTime->tv_sec >= 0, "tv_sec < 0");
4439 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs");
4440 assert(absTime->tv_nsec >= 0, "tv_nsec < 0");
4441 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec");
4442 }
4443
4444 void Parker::park(bool isAbsolute, jlong time) {
4445 // Ideally we'd do something useful while spinning, such
4446 // as calling unpackTime().
4447
4448 // Optional fast-path check:
4449 // Return immediately if a permit is available.
4450 // We depend on Atomic::xchg() having full barrier semantics
4451 // since we are doing a lock-free update to _counter.
4452 if (Atomic::xchg(0, &_counter) > 0) return;
4453
4454 Thread* thread = Thread::current();
4455 assert(thread->is_Java_thread(), "Must be JavaThread");
4456 JavaThread *jt = (JavaThread *)thread;
4457
4458 // Optional optimization -- avoid state transitions if there's an interrupt pending.
4459 // Check interrupt before trying to wait
4460 if (Thread::is_interrupted(thread, false)) {
4461 return;
4462 }
4463
4464 // Next, demultiplex/decode time arguments
4465 struct timespec absTime;
4466 if (time < 0 || (isAbsolute && time == 0) ) { // don't wait at all
4467 return;
4468 }
4469 if (time > 0) {
4470 unpackTime(&absTime, isAbsolute, time);
4471 }
4472
4473
4474 // Enter safepoint region
4475 // Beware of deadlocks such as 6317397.
4476 // The per-thread Parker:: mutex is a classic leaf-lock.
4477 // In particular a thread must never block on the Threads_lock while
4478 // holding the Parker:: mutex. If safepoints are pending both the
4479 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock.
4480 ThreadBlockInVM tbivm(jt);
4481
4482 // Don't wait if cannot get lock since interference arises from
4483 // unblocking. Also. check interrupt before trying wait
4484 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) {
4485 return;
4486 }
4487
4488 int status ;
4489 if (_counter > 0) { // no wait needed
4490 _counter = 0;
4491 status = pthread_mutex_unlock(_mutex);
4492 assert (status == 0, "invariant") ;
4493 // Paranoia to ensure our locked and lock-free paths interact
4494 // correctly with each other and Java-level accesses.
4495 OrderAccess::fence();
4496 return;
4497 }
4498
4499 #ifdef ASSERT
4500 // Don't catch signals while blocked; let the running threads have the signals.
4501 // (This allows a debugger to break into the running thread.)
4502 sigset_t oldsigs;
4503 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals();
4504 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs);
4505 #endif
4506
4507 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
4508 jt->set_suspend_equivalent();
4509 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
4510
4511 if (time == 0) {
4512 status = pthread_cond_wait (_cond, _mutex) ;
4513 } else {
4514 status = os::Bsd::safe_cond_timedwait (_cond, _mutex, &absTime) ;
4515 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4516 pthread_cond_destroy (_cond) ;
4517 pthread_cond_init (_cond, NULL);
4518 }
4519 }
4520 assert_status(status == 0 || status == EINTR ||
4521 status == ETIMEDOUT,
4522 status, "cond_timedwait");
4523
4524 #ifdef ASSERT
4525 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL);
4526 #endif
4527
4528 _counter = 0 ;
4529 status = pthread_mutex_unlock(_mutex) ;
4530 assert_status(status == 0, status, "invariant") ;
4531 // Paranoia to ensure our locked and lock-free paths interact
4532 // correctly with each other and Java-level accesses.
4533 OrderAccess::fence();
4534
4535 // If externally suspended while waiting, re-suspend
4536 if (jt->handle_special_suspend_equivalent_condition()) {
4537 jt->java_suspend_self();
4538 }
4539 }
4540
4541 void Parker::unpark() {
4542 int s, status ;
4543 status = pthread_mutex_lock(_mutex);
4544 assert (status == 0, "invariant") ;
4545 s = _counter;
4546 _counter = 1;
4547 if (s < 1) {
4548 if (WorkAroundNPTLTimedWaitHang) {
4549 status = pthread_cond_signal (_cond) ;
4550 assert (status == 0, "invariant") ;
4551 status = pthread_mutex_unlock(_mutex);
4552 assert (status == 0, "invariant") ;
4553 } else {
4554 status = pthread_mutex_unlock(_mutex);
4555 assert (status == 0, "invariant") ;
4556 status = pthread_cond_signal (_cond) ;
4557 assert (status == 0, "invariant") ;
4558 }
4559 } else {
4560 pthread_mutex_unlock(_mutex);
4561 assert (status == 0, "invariant") ;
4562 }
4563 }
4564
4565
4566 /* Darwin has no "environ" in a dynamic library. */
4567 #ifdef __APPLE__
4568 #include <crt_externs.h>
4569 #define environ (*_NSGetEnviron())
4570 #else
4571 extern char** environ;
4572 #endif
4573
4574 // Run the specified command in a separate process. Return its exit value,
4575 // or -1 on failure (e.g. can't fork a new process).
4576 // Unlike system(), this function can be called from signal handler. It
4577 // doesn't block SIGINT et al.
4578 int os::fork_and_exec(char* cmd) {
4579 const char * argv[4] = {"sh", "-c", cmd, NULL};
4580
4581 // fork() in BsdThreads/NPTL is not async-safe. It needs to run
4582 // pthread_atfork handlers and reset pthread library. All we need is a
4583 // separate process to execve. Make a direct syscall to fork process.
4584 // On IA64 there's no fork syscall, we have to use fork() and hope for
4585 // the best...
4586 pid_t pid = fork();
4587
4588 if (pid < 0) {
4589 // fork failed
4590 return -1;
4591
4592 } else if (pid == 0) {
4593 // child process
4594
4595 // execve() in BsdThreads will call pthread_kill_other_threads_np()
4596 // first to kill every thread on the thread list. Because this list is
4597 // not reset by fork() (see notes above), execve() will instead kill
4598 // every thread in the parent process. We know this is the only thread
4599 // in the new process, so make a system call directly.
4600 // IA64 should use normal execve() from glibc to match the glibc fork()
4601 // above.
4602 execve("/bin/sh", (char* const*)argv, environ);
4603
4604 // execve failed
4605 _exit(-1);
4606
4607 } else {
4608 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
4609 // care about the actual exit code, for now.
4610
4611 int status;
4612
4613 // Wait for the child process to exit. This returns immediately if
4614 // the child has already exited. */
4615 while (waitpid(pid, &status, 0) < 0) {
4616 switch (errno) {
4617 case ECHILD: return 0;
4618 case EINTR: break;
4619 default: return -1;
4620 }
4621 }
4622
4623 if (WIFEXITED(status)) {
4624 // The child exited normally; get its exit code.
4625 return WEXITSTATUS(status);
4626 } else if (WIFSIGNALED(status)) {
4627 // The child exited because of a signal
4628 // The best value to return is 0x80 + signal number,
4629 // because that is what all Unix shells do, and because
4630 // it allows callers to distinguish between process exit and
4631 // process death by signal.
4632 return 0x80 + WTERMSIG(status);
4633 } else {
4634 // Unknown exit code; pass it through
4635 return status;
4636 }
4637 }
4638 }
4639
4640 // is_headless_jre()
4641 //
4642 // Test for the existence of xawt/libmawt.so or libawt_xawt.so
4643 // in order to report if we are running in a headless jre
4644 //
4645 // Since JDK8 xawt/libmawt.so was moved into the same directory
4646 // as libawt.so, and renamed libawt_xawt.so
4647 //
4648 bool os::is_headless_jre() {
4649 #ifdef __APPLE__
4650 // We no longer build headless-only on Mac OS X
4651 return false;
4652 #else
4653 struct stat statbuf;
4654 char buf[MAXPATHLEN];
4655 char libmawtpath[MAXPATHLEN];
4656 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX;
4657 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX;
4658 char *p;
4659
4660 // Get path to libjvm.so
4661 os::jvm_path(buf, sizeof(buf));
4662
4663 // Get rid of libjvm.so
4664 p = strrchr(buf, '/');
4665 if (p == NULL) return false;
4666 else *p = '\0';
4667
4668 // Get rid of client or server
4669 p = strrchr(buf, '/');
4670 if (p == NULL) return false;
4671 else *p = '\0';
4672
4673 // check xawt/libmawt.so
4674 strcpy(libmawtpath, buf);
4675 strcat(libmawtpath, xawtstr);
4676 if (::stat(libmawtpath, &statbuf) == 0) return false;
4677
4678 // check libawt_xawt.so
4679 strcpy(libmawtpath, buf);
4680 strcat(libmawtpath, new_xawtstr);
4681 if (::stat(libmawtpath, &statbuf) == 0) return false;
4682
4683 return true;
4684 #endif
4685 }
4686
4687 // Get the default path to the core file
4688 // Returns the length of the string
4689 int os::get_core_path(char* buffer, size_t bufferSize) {
4690 int n = jio_snprintf(buffer, bufferSize, "/cores");
4691
4692 // Truncate if theoretical string was longer than bufferSize
4693 n = MIN2(n, (int)bufferSize);
4694
4695 return n;
4696 }
4697
4698 #ifndef PRODUCT
4699 void TestReserveMemorySpecial_test() {
4700 // No tests available for this platform
4701 }
4702 #endif