1 /*
2 * Copyright (c) 1999, 2015, 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_bsd.inline.hpp"
40 #include "os_share_bsd.hpp"
41 #include "prims/jniFastGetField.hpp"
42 #include "prims/jvm.h"
43 #include "prims/jvm_misc.hpp"
44 #include "runtime/arguments.hpp"
45 #include "runtime/atomic.inline.hpp"
46 #include "runtime/extendedPC.hpp"
47 #include "runtime/globals.hpp"
48 #include "runtime/interfaceSupport.hpp"
49 #include "runtime/java.hpp"
50 #include "runtime/javaCalls.hpp"
51 #include "runtime/mutexLocker.hpp"
52 #include "runtime/objectMonitor.hpp"
53 #include "runtime/orderAccess.inline.hpp"
54 #include "runtime/osThread.hpp"
55 #include "runtime/perfMemory.hpp"
56 #include "runtime/sharedRuntime.hpp"
57 #include "runtime/statSampler.hpp"
58 #include "runtime/stubRoutines.hpp"
59 #include "runtime/thread.inline.hpp"
60 #include "runtime/threadCritical.hpp"
61 #include "runtime/timer.hpp"
62 #include "semaphore_bsd.hpp"
63 #include "services/attachListener.hpp"
64 #include "services/memTracker.hpp"
65 #include "services/runtimeService.hpp"
66 #include "utilities/decoder.hpp"
67 #include "utilities/defaultStream.hpp"
68 #include "utilities/events.hpp"
69 #include "utilities/growableArray.hpp"
70 #include "utilities/vmError.hpp"
71
72 // put OS-includes here
73 # include <sys/types.h>
74 # include <sys/mman.h>
75 # include <sys/stat.h>
76 # include <sys/select.h>
77 # include <pthread.h>
78 # include <signal.h>
79 # include <errno.h>
80 # include <dlfcn.h>
81 # include <stdio.h>
82 # include <unistd.h>
83 # include <sys/resource.h>
84 # include <pthread.h>
85 # include <sys/stat.h>
86 # include <sys/time.h>
87 # include <sys/times.h>
88 # include <sys/utsname.h>
89 # include <sys/socket.h>
90 # include <sys/wait.h>
91 # include <time.h>
92 # include <pwd.h>
93 # include <poll.h>
94 # include <semaphore.h>
95 # include <fcntl.h>
96 # include <string.h>
97 # include <sys/param.h>
98 # include <sys/sysctl.h>
99 # include <sys/ipc.h>
100 # include <sys/shm.h>
101 #ifndef __APPLE__
102 # include <link.h>
103 #endif
104 # include <stdint.h>
105 # include <inttypes.h>
106 # include <sys/ioctl.h>
107 # include <sys/syscall.h>
108
109 #if defined(__FreeBSD__) || defined(__NetBSD__)
110 #include <elf.h>
111 #endif
112
113 #ifdef __APPLE__
114 #include <mach/mach.h> // semaphore_* API
115 #include <mach-o/dyld.h>
116 #include <sys/proc_info.h>
117 #include <objc/objc-auto.h>
118 #endif
119
120 #ifndef MAP_ANONYMOUS
121 #define MAP_ANONYMOUS MAP_ANON
122 #endif
123
124 #define MAX_PATH (2 * K)
125
126 // for timer info max values which include all bits
127 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF)
128
129 #define LARGEPAGES_BIT (1 << 6)
130
131 ////////////////////////////////////////////////////////////////////////////////
132 // global variables
133 julong os::Bsd::_physical_memory = 0;
134
135 #ifdef __APPLE__
136 mach_timebase_info_data_t os::Bsd::_timebase_info = {0, 0};
137 volatile uint64_t os::Bsd::_max_abstime = 0;
138 #else
139 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL;
140 #endif
141 pthread_t os::Bsd::_main_thread;
142 int os::Bsd::_page_size = -1;
143
144 static jlong initial_time_count=0;
145
146 static int clock_tics_per_sec = 100;
147
148 // For diagnostics to print a message once. see run_periodic_checks
149 static sigset_t check_signal_done;
150 static bool check_signals = true;
151
152 static pid_t _initial_pid = 0;
153
154 // Signal number used to suspend/resume a thread
155
156 // do not use any signal number less than SIGSEGV, see 4355769
157 static int SR_signum = SIGUSR2;
158 sigset_t SR_sigset;
159
160
161 ////////////////////////////////////////////////////////////////////////////////
162 // utility functions
163
164 static int SR_initialize();
165 static void unpackTime(timespec* absTime, bool isAbsolute, jlong time);
166
167 julong os::available_memory() {
168 return Bsd::available_memory();
169 }
170
171 // available here means free
172 julong os::Bsd::available_memory() {
173 uint64_t available = physical_memory() >> 2;
174 #ifdef __APPLE__
175 mach_msg_type_number_t count = HOST_VM_INFO64_COUNT;
176 vm_statistics64_data_t vmstat;
177 kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64,
178 (host_info64_t)&vmstat, &count);
179 assert(kerr == KERN_SUCCESS,
180 "host_statistics64 failed - check mach_host_self() and count");
181 if (kerr == KERN_SUCCESS) {
182 available = vmstat.free_count * os::vm_page_size();
183 }
184 #endif
185 return available;
186 }
187
188 julong os::physical_memory() {
189 return Bsd::physical_memory();
190 }
191
192 // Return true if user is running as root.
193
194 bool os::have_special_privileges() {
195 static bool init = false;
196 static bool privileges = false;
197 if (!init) {
198 privileges = (getuid() != geteuid()) || (getgid() != getegid());
199 init = true;
200 }
201 return privileges;
202 }
203
204
205
206 // Cpu architecture string
207 #if defined(ZERO)
208 static char cpu_arch[] = ZERO_LIBARCH;
209 #elif defined(IA64)
210 static char cpu_arch[] = "ia64";
211 #elif defined(IA32)
212 static char cpu_arch[] = "i386";
213 #elif defined(AMD64)
214 static char cpu_arch[] = "amd64";
215 #elif defined(ARM)
216 static char cpu_arch[] = "arm";
217 #elif defined(PPC32)
218 static char cpu_arch[] = "ppc";
219 #elif defined(SPARC)
220 #ifdef _LP64
221 static char cpu_arch[] = "sparcv9";
222 #else
223 static char cpu_arch[] = "sparc";
224 #endif
225 #else
226 #error Add appropriate cpu_arch setting
227 #endif
228
229 // Compiler variant
230 #ifdef COMPILER2
231 #define COMPILER_VARIANT "server"
232 #else
233 #define COMPILER_VARIANT "client"
234 #endif
235
236
237 void os::Bsd::initialize_system_info() {
238 int mib[2];
239 size_t len;
240 int cpu_val;
241 julong mem_val;
242
243 // get processors count via hw.ncpus sysctl
244 mib[0] = CTL_HW;
245 mib[1] = HW_NCPU;
246 len = sizeof(cpu_val);
247 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) {
248 assert(len == sizeof(cpu_val), "unexpected data size");
249 set_processor_count(cpu_val);
250 } else {
251 set_processor_count(1); // fallback
252 }
253
254 // get physical memory via hw.memsize sysctl (hw.memsize is used
255 // since it returns a 64 bit value)
256 mib[0] = CTL_HW;
257
258 #if defined (HW_MEMSIZE) // Apple
259 mib[1] = HW_MEMSIZE;
260 #elif defined(HW_PHYSMEM) // Most of BSD
261 mib[1] = HW_PHYSMEM;
262 #elif defined(HW_REALMEM) // Old FreeBSD
263 mib[1] = HW_REALMEM;
264 #else
265 #error No ways to get physmem
266 #endif
267
268 len = sizeof(mem_val);
269 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) {
270 assert(len == sizeof(mem_val), "unexpected data size");
271 _physical_memory = mem_val;
272 } else {
273 _physical_memory = 256 * 1024 * 1024; // fallback (XXXBSD?)
274 }
275
276 #ifdef __OpenBSD__
277 {
278 // limit _physical_memory memory view on OpenBSD since
279 // datasize rlimit restricts us anyway.
280 struct rlimit limits;
281 getrlimit(RLIMIT_DATA, &limits);
282 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur);
283 }
284 #endif
285 }
286
287 #ifdef __APPLE__
288 static const char *get_home() {
289 const char *home_dir = ::getenv("HOME");
290 if ((home_dir == NULL) || (*home_dir == '\0')) {
291 struct passwd *passwd_info = getpwuid(geteuid());
292 if (passwd_info != NULL) {
293 home_dir = passwd_info->pw_dir;
294 }
295 }
296
297 return home_dir;
298 }
299 #endif
300
301 void os::init_system_properties_values() {
302 // The next steps are taken in the product version:
303 //
304 // Obtain the JAVA_HOME value from the location of libjvm.so.
305 // This library should be located at:
306 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so.
307 //
308 // If "/jre/lib/" appears at the right place in the path, then we
309 // assume libjvm.so is installed in a JDK and we use this path.
310 //
311 // Otherwise exit with message: "Could not create the Java virtual machine."
312 //
313 // The following extra steps are taken in the debugging version:
314 //
315 // If "/jre/lib/" does NOT appear at the right place in the path
316 // instead of exit check for $JAVA_HOME environment variable.
317 //
318 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>,
319 // then we append a fake suffix "hotspot/libjvm.so" to this path so
320 // it looks like libjvm.so is installed there
321 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so.
322 //
323 // Otherwise exit.
324 //
325 // Important note: if the location of libjvm.so changes this
326 // code needs to be changed accordingly.
327
328 // See ld(1):
329 // The linker uses the following search paths to locate required
330 // shared libraries:
331 // 1: ...
332 // ...
333 // 7: The default directories, normally /lib and /usr/lib.
334 #ifndef DEFAULT_LIBPATH
335 #define DEFAULT_LIBPATH "/lib:/usr/lib"
336 #endif
337
338 // Base path of extensions installed on the system.
339 #define SYS_EXT_DIR "/usr/java/packages"
340 #define EXTENSIONS_DIR "/lib/ext"
341
342 #ifndef __APPLE__
343
344 // Buffer that fits several sprintfs.
345 // Note that the space for the colon and the trailing null are provided
346 // by the nulls included by the sizeof operator.
347 const size_t bufsize =
348 MAX2((size_t)MAXPATHLEN, // For dll_dir & friends.
349 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + sizeof(SYS_EXT_DIR) + sizeof(EXTENSIONS_DIR)); // extensions dir
350 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
351
352 // sysclasspath, java_home, dll_dir
353 {
354 char *pslash;
355 os::jvm_path(buf, bufsize);
356
357 // Found the full path to libjvm.so.
358 // Now cut the path to <java_home>/jre if we can.
359 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
360 pslash = strrchr(buf, '/');
361 if (pslash != NULL) {
362 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
363 }
364 Arguments::set_dll_dir(buf);
365
366 if (pslash != NULL) {
367 pslash = strrchr(buf, '/');
368 if (pslash != NULL) {
369 *pslash = '\0'; // Get rid of /<arch>.
370 pslash = strrchr(buf, '/');
371 if (pslash != NULL) {
372 *pslash = '\0'; // Get rid of /lib.
373 }
374 }
375 }
376 Arguments::set_java_home(buf);
377 set_boot_path('/', ':');
378 }
379
380 // Where to look for native libraries.
381 //
382 // Note: Due to a legacy implementation, most of the library path
383 // is set in the launcher. This was to accomodate linking restrictions
384 // on legacy Bsd implementations (which are no longer supported).
385 // Eventually, all the library path setting will be done here.
386 //
387 // However, to prevent the proliferation of improperly built native
388 // libraries, the new path component /usr/java/packages is added here.
389 // Eventually, all the library path setting will be done here.
390 {
391 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
392 // should always exist (until the legacy problem cited above is
393 // addressed).
394 const char *v = ::getenv("LD_LIBRARY_PATH");
395 const char *v_colon = ":";
396 if (v == NULL) { v = ""; v_colon = ""; }
397 // That's +1 for the colon and +1 for the trailing '\0'.
398 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char,
399 strlen(v) + 1 +
400 sizeof(SYS_EXT_DIR) + sizeof("/lib/") + strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH) + 1,
401 mtInternal);
402 sprintf(ld_library_path, "%s%s" SYS_EXT_DIR "/lib/%s:" DEFAULT_LIBPATH, v, v_colon, cpu_arch);
403 Arguments::set_library_path(ld_library_path);
404 FREE_C_HEAP_ARRAY(char, ld_library_path);
405 }
406
407 // Extensions directories.
408 sprintf(buf, "%s" EXTENSIONS_DIR ":" SYS_EXT_DIR EXTENSIONS_DIR, Arguments::get_java_home());
409 Arguments::set_ext_dirs(buf);
410
411 FREE_C_HEAP_ARRAY(char, buf);
412
413 #else // __APPLE__
414
415 #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions"
416 #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java"
417
418 const char *user_home_dir = get_home();
419 // The null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir.
420 size_t system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) +
421 sizeof(SYS_EXTENSIONS_DIRS);
422
423 // Buffer that fits several sprintfs.
424 // Note that the space for the colon and the trailing null are provided
425 // by the nulls included by the sizeof operator.
426 const size_t bufsize =
427 MAX2((size_t)MAXPATHLEN, // for dll_dir & friends.
428 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + system_ext_size); // extensions dir
429 char *buf = (char *)NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
430
431 // sysclasspath, java_home, dll_dir
432 {
433 char *pslash;
434 os::jvm_path(buf, bufsize);
435
436 // Found the full path to libjvm.so.
437 // Now cut the path to <java_home>/jre if we can.
438 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
439 pslash = strrchr(buf, '/');
440 if (pslash != NULL) {
441 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
442 }
443 #ifdef STATIC_BUILD
444 strcat(buf, "/lib");
445 #endif
446
447 Arguments::set_dll_dir(buf);
448
449 if (pslash != NULL) {
450 pslash = strrchr(buf, '/');
451 if (pslash != NULL) {
452 *pslash = '\0'; // Get rid of /lib.
453 }
454 }
455 Arguments::set_java_home(buf);
456 set_boot_path('/', ':');
457 }
458
459 // Where to look for native libraries.
460 //
461 // Note: Due to a legacy implementation, most of the library path
462 // is set in the launcher. This was to accomodate linking restrictions
463 // on legacy Bsd implementations (which are no longer supported).
464 // Eventually, all the library path setting will be done here.
465 //
466 // However, to prevent the proliferation of improperly built native
467 // libraries, the new path component /usr/java/packages is added here.
468 // Eventually, all the library path setting will be done here.
469 {
470 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
471 // should always exist (until the legacy problem cited above is
472 // addressed).
473 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code
474 // can specify a directory inside an app wrapper
475 const char *l = ::getenv("JAVA_LIBRARY_PATH");
476 const char *l_colon = ":";
477 if (l == NULL) { l = ""; l_colon = ""; }
478
479 const char *v = ::getenv("DYLD_LIBRARY_PATH");
480 const char *v_colon = ":";
481 if (v == NULL) { v = ""; v_colon = ""; }
482
483 // Apple's Java6 has "." at the beginning of java.library.path.
484 // OpenJDK on Windows has "." at the end of java.library.path.
485 // OpenJDK on Linux and Solaris don't have "." in java.library.path
486 // at all. To ease the transition from Apple's Java6 to OpenJDK7,
487 // "." is appended to the end of java.library.path. Yes, this
488 // could cause a change in behavior, but Apple's Java6 behavior
489 // can be achieved by putting "." at the beginning of the
490 // JAVA_LIBRARY_PATH environment variable.
491 char *ld_library_path = (char *)NEW_C_HEAP_ARRAY(char,
492 strlen(v) + 1 + strlen(l) + 1 +
493 system_ext_size + 3,
494 mtInternal);
495 sprintf(ld_library_path, "%s%s%s%s%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS ":.",
496 v, v_colon, l, l_colon, user_home_dir);
497 Arguments::set_library_path(ld_library_path);
498 FREE_C_HEAP_ARRAY(char, ld_library_path);
499 }
500
501 // Extensions directories.
502 //
503 // Note that the space for the colon and the trailing null are provided
504 // by the nulls included by the sizeof operator (so actually one byte more
505 // than necessary is allocated).
506 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS,
507 user_home_dir, Arguments::get_java_home());
508 Arguments::set_ext_dirs(buf);
509
510 FREE_C_HEAP_ARRAY(char, buf);
511
512 #undef SYS_EXTENSIONS_DIR
513 #undef SYS_EXTENSIONS_DIRS
514
515 #endif // __APPLE__
516
517 #undef SYS_EXT_DIR
518 #undef EXTENSIONS_DIR
519 }
520
521 ////////////////////////////////////////////////////////////////////////////////
522 // breakpoint support
523
524 void os::breakpoint() {
525 BREAKPOINT;
526 }
527
528 extern "C" void breakpoint() {
529 // use debugger to set breakpoint here
530 }
531
532 ////////////////////////////////////////////////////////////////////////////////
533 // signal support
534
535 debug_only(static bool signal_sets_initialized = false);
536 static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs;
537
538 bool os::Bsd::is_sig_ignored(int sig) {
539 struct sigaction oact;
540 sigaction(sig, (struct sigaction*)NULL, &oact);
541 void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction)
542 : CAST_FROM_FN_PTR(void*, oact.sa_handler);
543 if (ohlr == CAST_FROM_FN_PTR(void*, SIG_IGN)) {
544 return true;
545 } else {
546 return false;
547 }
548 }
549
550 void os::Bsd::signal_sets_init() {
551 // Should also have an assertion stating we are still single-threaded.
552 assert(!signal_sets_initialized, "Already initialized");
553 // Fill in signals that are necessarily unblocked for all threads in
554 // the VM. Currently, we unblock the following signals:
555 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
556 // by -Xrs (=ReduceSignalUsage));
557 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
558 // other threads. The "ReduceSignalUsage" boolean tells us not to alter
559 // the dispositions or masks wrt these signals.
560 // Programs embedding the VM that want to use the above signals for their
561 // own purposes must, at this time, use the "-Xrs" option to prevent
562 // interference with shutdown hooks and BREAK_SIGNAL thread dumping.
563 // (See bug 4345157, and other related bugs).
564 // In reality, though, unblocking these signals is really a nop, since
565 // these signals are not blocked by default.
566 sigemptyset(&unblocked_sigs);
567 sigemptyset(&allowdebug_blocked_sigs);
568 sigaddset(&unblocked_sigs, SIGILL);
569 sigaddset(&unblocked_sigs, SIGSEGV);
570 sigaddset(&unblocked_sigs, SIGBUS);
571 sigaddset(&unblocked_sigs, SIGFPE);
572 sigaddset(&unblocked_sigs, SR_signum);
573
574 if (!ReduceSignalUsage) {
575 if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
576 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
577 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL);
578 }
579 if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
580 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
581 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL);
582 }
583 if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
584 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
585 sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL);
586 }
587 }
588 // Fill in signals that are blocked by all but the VM thread.
589 sigemptyset(&vm_sigs);
590 if (!ReduceSignalUsage) {
591 sigaddset(&vm_sigs, BREAK_SIGNAL);
592 }
593 debug_only(signal_sets_initialized = true);
594
595 }
596
597 // These are signals that are unblocked while a thread is running Java.
598 // (For some reason, they get blocked by default.)
599 sigset_t* os::Bsd::unblocked_signals() {
600 assert(signal_sets_initialized, "Not initialized");
601 return &unblocked_sigs;
602 }
603
604 // These are the signals that are blocked while a (non-VM) thread is
605 // running Java. Only the VM thread handles these signals.
606 sigset_t* os::Bsd::vm_signals() {
607 assert(signal_sets_initialized, "Not initialized");
608 return &vm_sigs;
609 }
610
611 // These are signals that are blocked during cond_wait to allow debugger in
612 sigset_t* os::Bsd::allowdebug_blocked_signals() {
613 assert(signal_sets_initialized, "Not initialized");
614 return &allowdebug_blocked_sigs;
615 }
616
617 void os::Bsd::hotspot_sigmask(Thread* thread) {
618
619 //Save caller's signal mask before setting VM signal mask
620 sigset_t caller_sigmask;
621 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
622
623 OSThread* osthread = thread->osthread();
624 osthread->set_caller_sigmask(caller_sigmask);
625
626 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL);
627
628 if (!ReduceSignalUsage) {
629 if (thread->is_VM_thread()) {
630 // Only the VM thread handles BREAK_SIGNAL ...
631 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
632 } else {
633 // ... all other threads block BREAK_SIGNAL
634 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
635 }
636 }
637 }
638
639
640 //////////////////////////////////////////////////////////////////////////////
641 // create new thread
642
643 #ifdef __APPLE__
644 // library handle for calling objc_registerThreadWithCollector()
645 // without static linking to the libobjc library
646 #define OBJC_LIB "/usr/lib/libobjc.dylib"
647 #define OBJC_GCREGISTER "objc_registerThreadWithCollector"
648 typedef void (*objc_registerThreadWithCollector_t)();
649 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction;
650 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL;
651 #endif
652
653 #ifdef __APPLE__
654 static uint64_t locate_unique_thread_id(mach_port_t mach_thread_port) {
655 // Additional thread_id used to correlate threads in SA
656 thread_identifier_info_data_t m_ident_info;
657 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT;
658
659 thread_info(mach_thread_port, THREAD_IDENTIFIER_INFO,
660 (thread_info_t) &m_ident_info, &count);
661
662 return m_ident_info.thread_id;
663 }
664 #endif
665
666 // Thread start routine for all newly created threads
667 static void *java_start(Thread *thread) {
668 // Try to randomize the cache line index of hot stack frames.
669 // This helps when threads of the same stack traces evict each other's
670 // cache lines. The threads can be either from the same JVM instance, or
671 // from different JVM instances. The benefit is especially true for
672 // processors with hyperthreading technology.
673 static int counter = 0;
674 int pid = os::current_process_id();
675 alloca(((pid ^ counter++) & 7) * 128);
676
677 ThreadLocalStorage::set_thread(thread);
678
679 OSThread* osthread = thread->osthread();
680 Monitor* sync = osthread->startThread_lock();
681
682 osthread->set_thread_id(os::Bsd::gettid());
683
684 #ifdef __APPLE__
685 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
686 guarantee(unique_thread_id != 0, "unique thread id was not found");
687 osthread->set_unique_thread_id(unique_thread_id);
688 #endif
689 // initialize signal mask for this thread
690 os::Bsd::hotspot_sigmask(thread);
691
692 // initialize floating point control register
693 os::Bsd::init_thread_fpu_state();
694
695 #ifdef __APPLE__
696 // register thread with objc gc
697 if (objc_registerThreadWithCollectorFunction != NULL) {
698 objc_registerThreadWithCollectorFunction();
699 }
700 #endif
701
702 // handshaking with parent thread
703 {
704 MutexLockerEx ml(sync, Mutex::_no_safepoint_check_flag);
705
706 // notify parent thread
707 osthread->set_state(INITIALIZED);
708 sync->notify_all();
709
710 // wait until os::start_thread()
711 while (osthread->get_state() == INITIALIZED) {
712 sync->wait(Mutex::_no_safepoint_check_flag);
713 }
714 }
715
716 // call one more level start routine
717 thread->run();
718
719 return 0;
720 }
721
722 bool os::create_thread(Thread* thread, ThreadType thr_type, size_t stack_size) {
723 assert(thread->osthread() == NULL, "caller responsible");
724
725 // Allocate the OSThread object
726 OSThread* osthread = new OSThread(NULL, NULL);
727 if (osthread == NULL) {
728 return false;
729 }
730
731 // set the correct thread state
732 osthread->set_thread_type(thr_type);
733
734 // Initial state is ALLOCATED but not INITIALIZED
735 osthread->set_state(ALLOCATED);
736
737 thread->set_osthread(osthread);
738
739 // init thread attributes
740 pthread_attr_t attr;
741 pthread_attr_init(&attr);
742 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
743
744 // calculate stack size if it's not specified by caller
745 if (stack_size == 0) {
746 stack_size = os::Bsd::default_stack_size(thr_type);
747
748 switch (thr_type) {
749 case os::java_thread:
750 // Java threads use ThreadStackSize which default value can be
751 // changed with the flag -Xss
752 assert(JavaThread::stack_size_at_create() > 0, "this should be set");
753 stack_size = JavaThread::stack_size_at_create();
754 break;
755 case os::compiler_thread:
756 if (CompilerThreadStackSize > 0) {
757 stack_size = (size_t)(CompilerThreadStackSize * K);
758 break;
759 } // else fall through:
760 // use VMThreadStackSize if CompilerThreadStackSize is not defined
761 case os::vm_thread:
762 case os::pgc_thread:
763 case os::cgc_thread:
764 case os::watcher_thread:
765 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K);
766 break;
767 }
768 }
769
770 stack_size = MAX2(stack_size, os::Bsd::min_stack_allowed);
771 pthread_attr_setstacksize(&attr, stack_size);
772
773 ThreadState state;
774
775 {
776 pthread_t tid;
777 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) java_start, thread);
778
779 pthread_attr_destroy(&attr);
780
781 if (ret != 0) {
782 if (PrintMiscellaneous && (Verbose || WizardMode)) {
783 perror("pthread_create()");
784 }
785 // Need to clean up stuff we've allocated so far
786 thread->set_osthread(NULL);
787 delete osthread;
788 return false;
789 }
790
791 // Store pthread info into the OSThread
792 osthread->set_pthread_id(tid);
793
794 // Wait until child thread is either initialized or aborted
795 {
796 Monitor* sync_with_child = osthread->startThread_lock();
797 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
798 while ((state = osthread->get_state()) == ALLOCATED) {
799 sync_with_child->wait(Mutex::_no_safepoint_check_flag);
800 }
801 }
802
803 }
804
805 // Aborted due to thread limit being reached
806 if (state == ZOMBIE) {
807 thread->set_osthread(NULL);
808 delete osthread;
809 return false;
810 }
811
812 // The thread is returned suspended (in state INITIALIZED),
813 // and is started higher up in the call chain
814 assert(state == INITIALIZED, "race condition");
815 return true;
816 }
817
818 /////////////////////////////////////////////////////////////////////////////
819 // attach existing thread
820
821 // bootstrap the main thread
822 bool os::create_main_thread(JavaThread* thread) {
823 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
824 return create_attached_thread(thread);
825 }
826
827 bool os::create_attached_thread(JavaThread* thread) {
828 #ifdef ASSERT
829 thread->verify_not_published();
830 #endif
831
832 // Allocate the OSThread object
833 OSThread* osthread = new OSThread(NULL, NULL);
834
835 if (osthread == NULL) {
836 return false;
837 }
838
839 osthread->set_thread_id(os::Bsd::gettid());
840
841 // Store pthread info into the OSThread
842 #ifdef __APPLE__
843 uint64_t unique_thread_id = locate_unique_thread_id(osthread->thread_id());
844 guarantee(unique_thread_id != 0, "just checking");
845 osthread->set_unique_thread_id(unique_thread_id);
846 #endif
847 osthread->set_pthread_id(::pthread_self());
848
849 // initialize floating point control register
850 os::Bsd::init_thread_fpu_state();
851
852 // Initial thread state is RUNNABLE
853 osthread->set_state(RUNNABLE);
854
855 thread->set_osthread(osthread);
856
857 // initialize signal mask for this thread
858 // and save the caller's signal mask
859 os::Bsd::hotspot_sigmask(thread);
860
861 return true;
862 }
863
864 void os::pd_start_thread(Thread* thread) {
865 OSThread * osthread = thread->osthread();
866 assert(osthread->get_state() != INITIALIZED, "just checking");
867 Monitor* sync_with_child = osthread->startThread_lock();
868 MutexLockerEx ml(sync_with_child, Mutex::_no_safepoint_check_flag);
869 sync_with_child->notify();
870 }
871
872 // Free Bsd resources related to the OSThread
873 void os::free_thread(OSThread* osthread) {
874 assert(osthread != NULL, "osthread not set");
875
876 if (Thread::current()->osthread() == osthread) {
877 // Restore caller's signal mask
878 sigset_t sigmask = osthread->caller_sigmask();
879 pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
880 }
881
882 delete osthread;
883 }
884
885 //////////////////////////////////////////////////////////////////////////////
886 // thread local storage
887
888 // Restore the thread pointer if the destructor is called. This is in case
889 // someone from JNI code sets up a destructor with pthread_key_create to run
890 // detachCurrentThread on thread death. Unless we restore the thread pointer we
891 // will hang or crash. When detachCurrentThread is called the key will be set
892 // to null and we will not be called again. If detachCurrentThread is never
893 // called we could loop forever depending on the pthread implementation.
894 static void restore_thread_pointer(void* p) {
895 Thread* thread = (Thread*) p;
896 os::thread_local_storage_at_put(ThreadLocalStorage::thread_index(), thread);
897 }
898
899 int os::allocate_thread_local_storage() {
900 pthread_key_t key;
901 int rslt = pthread_key_create(&key, restore_thread_pointer);
902 assert(rslt == 0, "cannot allocate thread local storage");
903 return (int)key;
904 }
905
906 // Note: This is currently not used by VM, as we don't destroy TLS key
907 // on VM exit.
908 void os::free_thread_local_storage(int index) {
909 int rslt = pthread_key_delete((pthread_key_t)index);
910 assert(rslt == 0, "invalid index");
911 }
912
913 void os::thread_local_storage_at_put(int index, void* value) {
914 int rslt = pthread_setspecific((pthread_key_t)index, value);
915 assert(rslt == 0, "pthread_setspecific failed");
916 }
917
918 extern "C" Thread* get_thread() {
919 return ThreadLocalStorage::thread();
920 }
921
922
923 ////////////////////////////////////////////////////////////////////////////////
924 // time support
925
926 // Time since start-up in seconds to a fine granularity.
927 // Used by VMSelfDestructTimer and the MemProfiler.
928 double os::elapsedTime() {
929
930 return ((double)os::elapsed_counter()) / os::elapsed_frequency();
931 }
932
933 jlong os::elapsed_counter() {
934 return javaTimeNanos() - initial_time_count;
935 }
936
937 jlong os::elapsed_frequency() {
938 return NANOSECS_PER_SEC; // nanosecond resolution
939 }
940
941 bool os::supports_vtime() { return true; }
942 bool os::enable_vtime() { return false; }
943 bool os::vtime_enabled() { return false; }
944
945 double os::elapsedVTime() {
946 // better than nothing, but not much
947 return elapsedTime();
948 }
949
950 jlong os::javaTimeMillis() {
951 timeval time;
952 int status = gettimeofday(&time, NULL);
953 assert(status != -1, "bsd error");
954 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
955 }
956
957 void os::javaTimeSystemUTC(jlong &seconds, jlong &nanos) {
958 timeval time;
959 int status = gettimeofday(&time, NULL);
960 assert(status != -1, "bsd error");
961 seconds = jlong(time.tv_sec);
962 nanos = jlong(time.tv_usec) * 1000;
963 }
964
965 #ifndef __APPLE__
966 #ifndef CLOCK_MONOTONIC
967 #define CLOCK_MONOTONIC (1)
968 #endif
969 #endif
970
971 #ifdef __APPLE__
972 void os::Bsd::clock_init() {
973 mach_timebase_info(&_timebase_info);
974 }
975 #else
976 void os::Bsd::clock_init() {
977 struct timespec res;
978 struct timespec tp;
979 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
980 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) {
981 // yes, monotonic clock is supported
982 _clock_gettime = ::clock_gettime;
983 }
984 }
985 #endif
986
987
988
989 #ifdef __APPLE__
990
991 jlong os::javaTimeNanos() {
992 const uint64_t tm = mach_absolute_time();
993 const uint64_t now = (tm * Bsd::_timebase_info.numer) / Bsd::_timebase_info.denom;
994 const uint64_t prev = Bsd::_max_abstime;
995 if (now <= prev) {
996 return prev; // same or retrograde time;
997 }
998 const uint64_t obsv = Atomic::cmpxchg(now, (volatile jlong*)&Bsd::_max_abstime, prev);
999 assert(obsv >= prev, "invariant"); // Monotonicity
1000 // If the CAS succeeded then we're done and return "now".
1001 // If the CAS failed and the observed value "obsv" is >= now then
1002 // we should return "obsv". If the CAS failed and now > obsv > prv then
1003 // some other thread raced this thread and installed a new value, in which case
1004 // we could either (a) retry the entire operation, (b) retry trying to install now
1005 // or (c) just return obsv. We use (c). No loop is required although in some cases
1006 // we might discard a higher "now" value in deference to a slightly lower but freshly
1007 // installed obsv value. That's entirely benign -- it admits no new orderings compared
1008 // to (a) or (b) -- and greatly reduces coherence traffic.
1009 // We might also condition (c) on the magnitude of the delta between obsv and now.
1010 // Avoiding excessive CAS operations to hot RW locations is critical.
1011 // See https://blogs.oracle.com/dave/entry/cas_and_cache_trivia_invalidate
1012 return (prev == obsv) ? now : obsv;
1013 }
1014
1015 #else // __APPLE__
1016
1017 jlong os::javaTimeNanos() {
1018 if (os::supports_monotonic_clock()) {
1019 struct timespec tp;
1020 int status = Bsd::_clock_gettime(CLOCK_MONOTONIC, &tp);
1021 assert(status == 0, "gettime error");
1022 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
1023 return result;
1024 } else {
1025 timeval time;
1026 int status = gettimeofday(&time, NULL);
1027 assert(status != -1, "bsd error");
1028 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
1029 return 1000 * usecs;
1030 }
1031 }
1032
1033 #endif // __APPLE__
1034
1035 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
1036 if (os::supports_monotonic_clock()) {
1037 info_ptr->max_value = ALL_64_BITS;
1038
1039 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
1040 info_ptr->may_skip_backward = false; // not subject to resetting or drifting
1041 info_ptr->may_skip_forward = false; // not subject to resetting or drifting
1042 } else {
1043 // gettimeofday - based on time in seconds since the Epoch thus does not wrap
1044 info_ptr->max_value = ALL_64_BITS;
1045
1046 // gettimeofday is a real time clock so it skips
1047 info_ptr->may_skip_backward = true;
1048 info_ptr->may_skip_forward = true;
1049 }
1050
1051 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
1052 }
1053
1054 // Return the real, user, and system times in seconds from an
1055 // arbitrary fixed point in the past.
1056 bool os::getTimesSecs(double* process_real_time,
1057 double* process_user_time,
1058 double* process_system_time) {
1059 struct tms ticks;
1060 clock_t real_ticks = times(&ticks);
1061
1062 if (real_ticks == (clock_t) (-1)) {
1063 return false;
1064 } else {
1065 double ticks_per_second = (double) clock_tics_per_sec;
1066 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1067 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1068 *process_real_time = ((double) real_ticks) / ticks_per_second;
1069
1070 return true;
1071 }
1072 }
1073
1074
1075 char * os::local_time_string(char *buf, size_t buflen) {
1076 struct tm t;
1077 time_t long_time;
1078 time(&long_time);
1079 localtime_r(&long_time, &t);
1080 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1081 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1082 t.tm_hour, t.tm_min, t.tm_sec);
1083 return buf;
1084 }
1085
1086 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
1087 return localtime_r(clock, res);
1088 }
1089
1090 ////////////////////////////////////////////////////////////////////////////////
1091 // runtime exit support
1092
1093 // Note: os::shutdown() might be called very early during initialization, or
1094 // called from signal handler. Before adding something to os::shutdown(), make
1095 // sure it is async-safe and can handle partially initialized VM.
1096 void os::shutdown() {
1097
1098 // allow PerfMemory to attempt cleanup of any persistent resources
1099 perfMemory_exit();
1100
1101 // needs to remove object in file system
1102 AttachListener::abort();
1103
1104 // flush buffered output, finish log files
1105 ostream_abort();
1106
1107 // Check for abort hook
1108 abort_hook_t abort_hook = Arguments::abort_hook();
1109 if (abort_hook != NULL) {
1110 abort_hook();
1111 }
1112
1113 }
1114
1115 // Note: os::abort() might be called very early during initialization, or
1116 // called from signal handler. Before adding something to os::abort(), make
1117 // sure it is async-safe and can handle partially initialized VM.
1118 void os::abort(bool dump_core, void* siginfo, void* context) {
1119 os::shutdown();
1120 if (dump_core) {
1121 #ifndef PRODUCT
1122 fdStream out(defaultStream::output_fd());
1123 out.print_raw("Current thread is ");
1124 char buf[16];
1125 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
1126 out.print_raw_cr(buf);
1127 out.print_raw_cr("Dumping core ...");
1128 #endif
1129 ::abort(); // dump core
1130 }
1131
1132 ::exit(1);
1133 }
1134
1135 // Die immediately, no exit hook, no abort hook, no cleanup.
1136 void os::die() {
1137 // _exit() on BsdThreads only kills current thread
1138 ::abort();
1139 }
1140
1141 // This method is a copy of JDK's sysGetLastErrorString
1142 // from src/solaris/hpi/src/system_md.c
1143
1144 size_t os::lasterror(char *buf, size_t len) {
1145 if (errno == 0) return 0;
1146
1147 const char *s = ::strerror(errno);
1148 size_t n = ::strlen(s);
1149 if (n >= len) {
1150 n = len - 1;
1151 }
1152 ::strncpy(buf, s, n);
1153 buf[n] = '\0';
1154 return n;
1155 }
1156
1157 // Information of current thread in variety of formats
1158 pid_t os::Bsd::gettid() {
1159 int retval = -1;
1160
1161 #ifdef __APPLE__ //XNU kernel
1162 // despite the fact mach port is actually not a thread id use it
1163 // instead of syscall(SYS_thread_selfid) as it certainly fits to u4
1164 retval = ::pthread_mach_thread_np(::pthread_self());
1165 guarantee(retval != 0, "just checking");
1166 return retval;
1167
1168 #else
1169 #ifdef __FreeBSD__
1170 retval = syscall(SYS_thr_self);
1171 #else
1172 #ifdef __OpenBSD__
1173 retval = syscall(SYS_getthrid);
1174 #else
1175 #ifdef __NetBSD__
1176 retval = (pid_t) syscall(SYS__lwp_self);
1177 #endif
1178 #endif
1179 #endif
1180 #endif
1181
1182 if (retval == -1) {
1183 return getpid();
1184 }
1185 }
1186
1187 intx os::current_thread_id() {
1188 #ifdef __APPLE__
1189 return (intx)::pthread_mach_thread_np(::pthread_self());
1190 #else
1191 return (intx)::pthread_self();
1192 #endif
1193 }
1194
1195 int os::current_process_id() {
1196
1197 // Under the old bsd thread library, bsd gives each thread
1198 // its own process id. Because of this each thread will return
1199 // a different pid if this method were to return the result
1200 // of getpid(2). Bsd provides no api that returns the pid
1201 // of the launcher thread for the vm. This implementation
1202 // returns a unique pid, the pid of the launcher thread
1203 // that starts the vm 'process'.
1204
1205 // Under the NPTL, getpid() returns the same pid as the
1206 // launcher thread rather than a unique pid per thread.
1207 // Use gettid() if you want the old pre NPTL behaviour.
1208
1209 // if you are looking for the result of a call to getpid() that
1210 // returns a unique pid for the calling thread, then look at the
1211 // OSThread::thread_id() method in osThread_bsd.hpp file
1212
1213 return (int)(_initial_pid ? _initial_pid : getpid());
1214 }
1215
1216 // DLL functions
1217
1218 #define JNI_LIB_PREFIX "lib"
1219 #ifdef __APPLE__
1220 #define JNI_LIB_SUFFIX ".dylib"
1221 #else
1222 #define JNI_LIB_SUFFIX ".so"
1223 #endif
1224
1225 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1226
1227 // This must be hard coded because it's the system's temporary
1228 // directory not the java application's temp directory, ala java.io.tmpdir.
1229 #ifdef __APPLE__
1230 // macosx has a secure per-user temporary directory
1231 char temp_path_storage[PATH_MAX];
1232 const char* os::get_temp_directory() {
1233 static char *temp_path = NULL;
1234 if (temp_path == NULL) {
1235 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
1236 if (pathSize == 0 || pathSize > PATH_MAX) {
1237 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
1238 }
1239 temp_path = temp_path_storage;
1240 }
1241 return temp_path;
1242 }
1243 #else // __APPLE__
1244 const char* os::get_temp_directory() { return "/tmp"; }
1245 #endif // __APPLE__
1246
1247 static bool file_exists(const char* filename) {
1248 struct stat statbuf;
1249 if (filename == NULL || strlen(filename) == 0) {
1250 return false;
1251 }
1252 return os::stat(filename, &statbuf) == 0;
1253 }
1254
1255 bool os::dll_build_name(char* buffer, size_t buflen,
1256 const char* pname, const char* fname) {
1257 bool retval = false;
1258 // Copied from libhpi
1259 const size_t pnamelen = pname ? strlen(pname) : 0;
1260
1261 // Return error on buffer overflow.
1262 if (pnamelen + strlen(fname) + strlen(JNI_LIB_PREFIX) + strlen(JNI_LIB_SUFFIX) + 2 > buflen) {
1263 return retval;
1264 }
1265
1266 if (pnamelen == 0) {
1267 snprintf(buffer, buflen, JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, fname);
1268 retval = true;
1269 } else if (strchr(pname, *os::path_separator()) != NULL) {
1270 int n;
1271 char** pelements = split_path(pname, &n);
1272 if (pelements == NULL) {
1273 return false;
1274 }
1275 for (int i = 0; i < n; i++) {
1276 // Really shouldn't be NULL, but check can't hurt
1277 if (pelements[i] == NULL || strlen(pelements[i]) == 0) {
1278 continue; // skip the empty path values
1279 }
1280 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX,
1281 pelements[i], fname);
1282 if (file_exists(buffer)) {
1283 retval = true;
1284 break;
1285 }
1286 }
1287 // release the storage
1288 for (int i = 0; i < n; i++) {
1289 if (pelements[i] != NULL) {
1290 FREE_C_HEAP_ARRAY(char, pelements[i]);
1291 }
1292 }
1293 if (pelements != NULL) {
1294 FREE_C_HEAP_ARRAY(char*, pelements);
1295 }
1296 } else {
1297 snprintf(buffer, buflen, "%s/" JNI_LIB_PREFIX "%s" JNI_LIB_SUFFIX, pname, fname);
1298 retval = true;
1299 }
1300 return retval;
1301 }
1302
1303 // check if addr is inside libjvm.so
1304 bool os::address_is_in_vm(address addr) {
1305 static address libjvm_base_addr;
1306 Dl_info dlinfo;
1307
1308 if (libjvm_base_addr == NULL) {
1309 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) {
1310 libjvm_base_addr = (address)dlinfo.dli_fbase;
1311 }
1312 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1313 }
1314
1315 if (dladdr((void *)addr, &dlinfo) != 0) {
1316 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1317 }
1318
1319 return false;
1320 }
1321
1322
1323 #define MACH_MAXSYMLEN 256
1324
1325 bool os::dll_address_to_function_name(address addr, char *buf,
1326 int buflen, int *offset,
1327 bool demangle) {
1328 // buf is not optional, but offset is optional
1329 assert(buf != NULL, "sanity check");
1330
1331 Dl_info dlinfo;
1332 char localbuf[MACH_MAXSYMLEN];
1333
1334 if (dladdr((void*)addr, &dlinfo) != 0) {
1335 // see if we have a matching symbol
1336 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) {
1337 if (!(demangle && Decoder::demangle(dlinfo.dli_sname, buf, buflen))) {
1338 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1339 }
1340 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1341 return true;
1342 }
1343 // no matching symbol so try for just file info
1344 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) {
1345 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1346 buf, buflen, offset, dlinfo.dli_fname, demangle)) {
1347 return true;
1348 }
1349 }
1350
1351 // Handle non-dynamic manually:
1352 if (dlinfo.dli_fbase != NULL &&
1353 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset,
1354 dlinfo.dli_fbase)) {
1355 if (!(demangle && Decoder::demangle(localbuf, buf, buflen))) {
1356 jio_snprintf(buf, buflen, "%s", localbuf);
1357 }
1358 return true;
1359 }
1360 }
1361 buf[0] = '\0';
1362 if (offset != NULL) *offset = -1;
1363 return false;
1364 }
1365
1366 // ported from solaris version
1367 bool os::dll_address_to_library_name(address addr, char* buf,
1368 int buflen, int* offset) {
1369 // buf is not optional, but offset is optional
1370 assert(buf != NULL, "sanity check");
1371
1372 Dl_info dlinfo;
1373
1374 if (dladdr((void*)addr, &dlinfo) != 0) {
1375 if (dlinfo.dli_fname != NULL) {
1376 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1377 }
1378 if (dlinfo.dli_fbase != NULL && offset != NULL) {
1379 *offset = addr - (address)dlinfo.dli_fbase;
1380 }
1381 return true;
1382 }
1383
1384 buf[0] = '\0';
1385 if (offset) *offset = -1;
1386 return false;
1387 }
1388
1389 // Loads .dll/.so and
1390 // in case of error it checks if .dll/.so was built for the
1391 // same architecture as Hotspot is running on
1392
1393 #ifdef __APPLE__
1394 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1395 #ifdef STATIC_BUILD
1396 return os::get_default_process_handle();
1397 #else
1398 void * result= ::dlopen(filename, RTLD_LAZY);
1399 if (result != NULL) {
1400 // Successful loading
1401 return result;
1402 }
1403
1404 // Read system error message into ebuf
1405 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1406 ebuf[ebuflen-1]='\0';
1407
1408 return NULL;
1409 #endif // STATIC_BUILD
1410 }
1411 #else
1412 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1413 #ifdef STATIC_BUILD
1414 return os::get_default_process_handle();
1415 #else
1416 void * result= ::dlopen(filename, RTLD_LAZY);
1417 if (result != NULL) {
1418 // Successful loading
1419 return result;
1420 }
1421
1422 Elf32_Ehdr elf_head;
1423
1424 // Read system error message into ebuf
1425 // It may or may not be overwritten below
1426 ::strncpy(ebuf, ::dlerror(), ebuflen-1);
1427 ebuf[ebuflen-1]='\0';
1428 int diag_msg_max_length=ebuflen-strlen(ebuf);
1429 char* diag_msg_buf=ebuf+strlen(ebuf);
1430
1431 if (diag_msg_max_length==0) {
1432 // No more space in ebuf for additional diagnostics message
1433 return NULL;
1434 }
1435
1436
1437 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1438
1439 if (file_descriptor < 0) {
1440 // Can't open library, report dlerror() message
1441 return NULL;
1442 }
1443
1444 bool failed_to_read_elf_head=
1445 (sizeof(elf_head)!=
1446 (::read(file_descriptor, &elf_head,sizeof(elf_head))));
1447
1448 ::close(file_descriptor);
1449 if (failed_to_read_elf_head) {
1450 // file i/o error - report dlerror() msg
1451 return NULL;
1452 }
1453
1454 typedef struct {
1455 Elf32_Half code; // Actual value as defined in elf.h
1456 Elf32_Half compat_class; // Compatibility of archs at VM's sense
1457 char elf_class; // 32 or 64 bit
1458 char endianess; // MSB or LSB
1459 char* name; // String representation
1460 } arch_t;
1461
1462 #ifndef EM_486
1463 #define EM_486 6 /* Intel 80486 */
1464 #endif
1465
1466 #ifndef EM_MIPS_RS3_LE
1467 #define EM_MIPS_RS3_LE 10 /* MIPS */
1468 #endif
1469
1470 #ifndef EM_PPC64
1471 #define EM_PPC64 21 /* PowerPC64 */
1472 #endif
1473
1474 #ifndef EM_S390
1475 #define EM_S390 22 /* IBM System/390 */
1476 #endif
1477
1478 #ifndef EM_IA_64
1479 #define EM_IA_64 50 /* HP/Intel IA-64 */
1480 #endif
1481
1482 #ifndef EM_X86_64
1483 #define EM_X86_64 62 /* AMD x86-64 */
1484 #endif
1485
1486 static const arch_t arch_array[]={
1487 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1488 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1489 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
1490 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
1491 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1492 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1493 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
1494 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
1495 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
1496 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"},
1497 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
1498 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
1499 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
1500 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
1501 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
1502 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
1503 };
1504
1505 #if (defined IA32)
1506 static Elf32_Half running_arch_code=EM_386;
1507 #elif (defined AMD64)
1508 static Elf32_Half running_arch_code=EM_X86_64;
1509 #elif (defined IA64)
1510 static Elf32_Half running_arch_code=EM_IA_64;
1511 #elif (defined __sparc) && (defined _LP64)
1512 static Elf32_Half running_arch_code=EM_SPARCV9;
1513 #elif (defined __sparc) && (!defined _LP64)
1514 static Elf32_Half running_arch_code=EM_SPARC;
1515 #elif (defined __powerpc64__)
1516 static Elf32_Half running_arch_code=EM_PPC64;
1517 #elif (defined __powerpc__)
1518 static Elf32_Half running_arch_code=EM_PPC;
1519 #elif (defined ARM)
1520 static Elf32_Half running_arch_code=EM_ARM;
1521 #elif (defined S390)
1522 static Elf32_Half running_arch_code=EM_S390;
1523 #elif (defined ALPHA)
1524 static Elf32_Half running_arch_code=EM_ALPHA;
1525 #elif (defined MIPSEL)
1526 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
1527 #elif (defined PARISC)
1528 static Elf32_Half running_arch_code=EM_PARISC;
1529 #elif (defined MIPS)
1530 static Elf32_Half running_arch_code=EM_MIPS;
1531 #elif (defined M68K)
1532 static Elf32_Half running_arch_code=EM_68K;
1533 #else
1534 #error Method os::dll_load requires that one of following is defined:\
1535 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
1536 #endif
1537
1538 // Identify compatability class for VM's architecture and library's architecture
1539 // Obtain string descriptions for architectures
1540
1541 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
1542 int running_arch_index=-1;
1543
1544 for (unsigned int i=0; i < ARRAY_SIZE(arch_array); i++) {
1545 if (running_arch_code == arch_array[i].code) {
1546 running_arch_index = i;
1547 }
1548 if (lib_arch.code == arch_array[i].code) {
1549 lib_arch.compat_class = arch_array[i].compat_class;
1550 lib_arch.name = arch_array[i].name;
1551 }
1552 }
1553
1554 assert(running_arch_index != -1,
1555 "Didn't find running architecture code (running_arch_code) in arch_array");
1556 if (running_arch_index == -1) {
1557 // Even though running architecture detection failed
1558 // we may still continue with reporting dlerror() message
1559 return NULL;
1560 }
1561
1562 if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
1563 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
1564 return NULL;
1565 }
1566
1567 #ifndef S390
1568 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
1569 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
1570 return NULL;
1571 }
1572 #endif // !S390
1573
1574 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
1575 if (lib_arch.name!=NULL) {
1576 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1577 " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
1578 lib_arch.name, arch_array[running_arch_index].name);
1579 } else {
1580 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1581 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
1582 lib_arch.code,
1583 arch_array[running_arch_index].name);
1584 }
1585 }
1586
1587 return NULL;
1588 #endif // STATIC_BUILD
1589 }
1590 #endif // !__APPLE__
1591
1592 void* os::get_default_process_handle() {
1593 #ifdef __APPLE__
1594 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY
1595 // to avoid finding unexpected symbols on second (or later)
1596 // loads of a library.
1597 return (void*)::dlopen(NULL, RTLD_FIRST);
1598 #else
1599 return (void*)::dlopen(NULL, RTLD_LAZY);
1600 #endif
1601 }
1602
1603 // XXX: Do we need a lock around this as per Linux?
1604 void* os::dll_lookup(void* handle, const char* name) {
1605 return dlsym(handle, name);
1606 }
1607
1608 int _print_dll_info_cb(const char * name, address base_address, address top_address, void * param) {
1609 outputStream * out = (outputStream *) param;
1610 out->print_cr(PTR_FORMAT " \t%s", base_address, name);
1611 return 0;
1612 }
1613
1614 void os::print_dll_info(outputStream *st) {
1615 st->print_cr("Dynamic libraries:");
1616 if (get_loaded_modules_info(_print_dll_info_cb, (void *)st)) {
1617 st->print_cr("Error: Cannot print dynamic libraries.");
1618 }
1619 }
1620
1621 int os::get_loaded_modules_info(os::LoadedModulesCallbackFunc callback, void *param) {
1622 #ifdef RTLD_DI_LINKMAP
1623 Dl_info dli;
1624 void *handle;
1625 Link_map *map;
1626 Link_map *p;
1627
1628 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 ||
1629 dli.dli_fname == NULL) {
1630 return 1;
1631 }
1632 handle = dlopen(dli.dli_fname, RTLD_LAZY);
1633 if (handle == NULL) {
1634 return 1;
1635 }
1636 dlinfo(handle, RTLD_DI_LINKMAP, &map);
1637 if (map == NULL) {
1638 dlclose(handle);
1639 return 1;
1640 }
1641
1642 while (map->l_prev != NULL)
1643 map = map->l_prev;
1644
1645 while (map != NULL) {
1646 // Value for top_address is returned as 0 since we don't have any information about module size
1647 if (callback(map->l_name, (address)map->l_addr, (address)0, param)) {
1648 dlclose(handle);
1649 return 1;
1650 }
1651 map = map->l_next;
1652 }
1653
1654 dlclose(handle);
1655 #elif defined(__APPLE__)
1656 for (uint32_t i = 1; i < _dyld_image_count(); i++) {
1657 // Value for top_address is returned as 0 since we don't have any information about module size
1658 if (callback(_dyld_get_image_name(i), (address)_dyld_get_image_header(i), (address)0, param)) {
1659 return 1;
1660 }
1661 }
1662 return 0;
1663 #else
1664 return 1;
1665 #endif
1666 }
1667
1668 void os::get_summary_os_info(char* buf, size_t buflen) {
1669 // These buffers are small because we want this to be brief
1670 // and not use a lot of stack while generating the hs_err file.
1671 char os[100];
1672 size_t size = sizeof(os);
1673 int mib_kern[] = { CTL_KERN, KERN_OSTYPE };
1674 if (sysctl(mib_kern, 2, os, &size, NULL, 0) < 0) {
1675 #ifdef __APPLE__
1676 strncpy(os, "Darwin", sizeof(os));
1677 #elif __OpenBSD__
1678 strncpy(os, "OpenBSD", sizeof(os));
1679 #else
1680 strncpy(os, "BSD", sizeof(os));
1681 #endif
1682 }
1683
1684 char release[100];
1685 size = sizeof(release);
1686 int mib_release[] = { CTL_KERN, KERN_OSRELEASE };
1687 if (sysctl(mib_release, 2, release, &size, NULL, 0) < 0) {
1688 // if error, leave blank
1689 strncpy(release, "", sizeof(release));
1690 }
1691 snprintf(buf, buflen, "%s %s", os, release);
1692 }
1693
1694 void os::print_os_info_brief(outputStream* st) {
1695 os::Posix::print_uname_info(st);
1696 }
1697
1698 void os::print_os_info(outputStream* st) {
1699 st->print("OS:");
1700
1701 os::Posix::print_uname_info(st);
1702
1703 os::Posix::print_rlimit_info(st);
1704
1705 os::Posix::print_load_average(st);
1706 }
1707
1708 void os::pd_print_cpu_info(outputStream* st, char* buf, size_t buflen) {
1709 // Nothing to do for now.
1710 }
1711
1712 void os::get_summary_cpu_info(char* buf, size_t buflen) {
1713 unsigned int mhz;
1714 size_t size = sizeof(mhz);
1715 int mib[] = { CTL_HW, HW_CPU_FREQ };
1716 if (sysctl(mib, 2, &mhz, &size, NULL, 0) < 0) {
1717 mhz = 1; // looks like an error but can be divided by
1718 } else {
1719 mhz /= 1000000; // reported in millions
1720 }
1721
1722 char model[100];
1723 size = sizeof(model);
1724 int mib_model[] = { CTL_HW, HW_MODEL };
1725 if (sysctl(mib_model, 2, model, &size, NULL, 0) < 0) {
1726 strncpy(model, cpu_arch, sizeof(model));
1727 }
1728
1729 char machine[100];
1730 size = sizeof(machine);
1731 int mib_machine[] = { CTL_HW, HW_MACHINE };
1732 if (sysctl(mib_machine, 2, machine, &size, NULL, 0) < 0) {
1733 strncpy(machine, "", sizeof(machine));
1734 }
1735
1736 snprintf(buf, buflen, "%s %s %d MHz", model, machine, mhz);
1737 }
1738
1739 void os::print_memory_info(outputStream* st) {
1740
1741 st->print("Memory:");
1742 st->print(" %dk page", os::vm_page_size()>>10);
1743
1744 st->print(", physical " UINT64_FORMAT "k",
1745 os::physical_memory() >> 10);
1746 st->print("(" UINT64_FORMAT "k free)",
1747 os::available_memory() >> 10);
1748 st->cr();
1749 }
1750
1751 void os::print_siginfo(outputStream* st, void* siginfo) {
1752 const siginfo_t* si = (const siginfo_t*)siginfo;
1753
1754 os::Posix::print_siginfo_brief(st, si);
1755
1756 if (si && (si->si_signo == SIGBUS || si->si_signo == SIGSEGV) &&
1757 UseSharedSpaces) {
1758 FileMapInfo* mapinfo = FileMapInfo::current_info();
1759 if (mapinfo->is_in_shared_space(si->si_addr)) {
1760 st->print("\n\nError accessing class data sharing archive." \
1761 " Mapped file inaccessible during execution, " \
1762 " possible disk/network problem.");
1763 }
1764 }
1765 st->cr();
1766 }
1767
1768
1769 static void print_signal_handler(outputStream* st, int sig,
1770 char* buf, size_t buflen);
1771
1772 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1773 st->print_cr("Signal Handlers:");
1774 print_signal_handler(st, SIGSEGV, buf, buflen);
1775 print_signal_handler(st, SIGBUS , buf, buflen);
1776 print_signal_handler(st, SIGFPE , buf, buflen);
1777 print_signal_handler(st, SIGPIPE, buf, buflen);
1778 print_signal_handler(st, SIGXFSZ, buf, buflen);
1779 print_signal_handler(st, SIGILL , buf, buflen);
1780 print_signal_handler(st, SR_signum, buf, buflen);
1781 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1782 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1783 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1784 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1785 }
1786
1787 static char saved_jvm_path[MAXPATHLEN] = {0};
1788
1789 // Find the full path to the current module, libjvm
1790 void os::jvm_path(char *buf, jint buflen) {
1791 // Error checking.
1792 if (buflen < MAXPATHLEN) {
1793 assert(false, "must use a large-enough buffer");
1794 buf[0] = '\0';
1795 return;
1796 }
1797 // Lazy resolve the path to current module.
1798 if (saved_jvm_path[0] != 0) {
1799 strcpy(buf, saved_jvm_path);
1800 return;
1801 }
1802
1803 char dli_fname[MAXPATHLEN];
1804 bool ret = dll_address_to_library_name(
1805 CAST_FROM_FN_PTR(address, os::jvm_path),
1806 dli_fname, sizeof(dli_fname), NULL);
1807 assert(ret, "cannot locate libjvm");
1808 char *rp = NULL;
1809 if (ret && dli_fname[0] != '\0') {
1810 rp = realpath(dli_fname, buf);
1811 }
1812 if (rp == NULL) {
1813 return;
1814 }
1815
1816 if (Arguments::sun_java_launcher_is_altjvm()) {
1817 // Support for the java launcher's '-XXaltjvm=<path>' option. Typical
1818 // value for buf is "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so"
1819 // or "<JAVA_HOME>/jre/lib/<vmtype>/libjvm.dylib". If "/jre/lib/"
1820 // appears at the right place in the string, then assume we are
1821 // installed in a JDK and we're done. Otherwise, check for a
1822 // JAVA_HOME environment variable and construct a path to the JVM
1823 // being overridden.
1824
1825 const char *p = buf + strlen(buf) - 1;
1826 for (int count = 0; p > buf && count < 5; ++count) {
1827 for (--p; p > buf && *p != '/'; --p)
1828 /* empty */ ;
1829 }
1830
1831 if (strncmp(p, "/jre/lib/", 9) != 0) {
1832 // Look for JAVA_HOME in the environment.
1833 char* java_home_var = ::getenv("JAVA_HOME");
1834 if (java_home_var != NULL && java_home_var[0] != 0) {
1835 char* jrelib_p;
1836 int len;
1837
1838 // Check the current module name "libjvm"
1839 p = strrchr(buf, '/');
1840 assert(strstr(p, "/libjvm") == p, "invalid library name");
1841
1842 rp = realpath(java_home_var, buf);
1843 if (rp == NULL) {
1844 return;
1845 }
1846
1847 // determine if this is a legacy image or modules image
1848 // modules image doesn't have "jre" subdirectory
1849 len = strlen(buf);
1850 assert(len < buflen, "Ran out of buffer space");
1851 jrelib_p = buf + len;
1852
1853 // Add the appropriate library subdir
1854 snprintf(jrelib_p, buflen-len, "/jre/lib");
1855 if (0 != access(buf, F_OK)) {
1856 snprintf(jrelib_p, buflen-len, "/lib");
1857 }
1858
1859 // Add the appropriate client or server subdir
1860 len = strlen(buf);
1861 jrelib_p = buf + len;
1862 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
1863 if (0 != access(buf, F_OK)) {
1864 snprintf(jrelib_p, buflen-len, "%s", "");
1865 }
1866
1867 // If the path exists within JAVA_HOME, add the JVM library name
1868 // to complete the path to JVM being overridden. Otherwise fallback
1869 // to the path to the current library.
1870 if (0 == access(buf, F_OK)) {
1871 // Use current module name "libjvm"
1872 len = strlen(buf);
1873 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
1874 } else {
1875 // Fall back to path of current library
1876 rp = realpath(dli_fname, buf);
1877 if (rp == NULL) {
1878 return;
1879 }
1880 }
1881 }
1882 }
1883 }
1884
1885 strncpy(saved_jvm_path, buf, MAXPATHLEN);
1886 saved_jvm_path[MAXPATHLEN - 1] = '\0';
1887 }
1888
1889 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1890 // no prefix required, not even "_"
1891 }
1892
1893 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1894 // no suffix required
1895 }
1896
1897 ////////////////////////////////////////////////////////////////////////////////
1898 // sun.misc.Signal support
1899
1900 static volatile jint sigint_count = 0;
1901
1902 static void UserHandler(int sig, void *siginfo, void *context) {
1903 // 4511530 - sem_post is serialized and handled by the manager thread. When
1904 // the program is interrupted by Ctrl-C, SIGINT is sent to every thread. We
1905 // don't want to flood the manager thread with sem_post requests.
1906 if (sig == SIGINT && Atomic::add(1, &sigint_count) > 1) {
1907 return;
1908 }
1909
1910 // Ctrl-C is pressed during error reporting, likely because the error
1911 // handler fails to abort. Let VM die immediately.
1912 if (sig == SIGINT && is_error_reported()) {
1913 os::die();
1914 }
1915
1916 os::signal_notify(sig);
1917 }
1918
1919 void* os::user_handler() {
1920 return CAST_FROM_FN_PTR(void*, UserHandler);
1921 }
1922
1923 extern "C" {
1924 typedef void (*sa_handler_t)(int);
1925 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1926 }
1927
1928 void* os::signal(int signal_number, void* handler) {
1929 struct sigaction sigAct, oldSigAct;
1930
1931 sigfillset(&(sigAct.sa_mask));
1932 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
1933 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1934
1935 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1936 // -1 means registration failed
1937 return (void *)-1;
1938 }
1939
1940 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1941 }
1942
1943 void os::signal_raise(int signal_number) {
1944 ::raise(signal_number);
1945 }
1946
1947 // The following code is moved from os.cpp for making this
1948 // code platform specific, which it is by its very nature.
1949
1950 // Will be modified when max signal is changed to be dynamic
1951 int os::sigexitnum_pd() {
1952 return NSIG;
1953 }
1954
1955 // a counter for each possible signal value
1956 static volatile jint pending_signals[NSIG+1] = { 0 };
1957
1958 // Bsd(POSIX) specific hand shaking semaphore.
1959 #ifdef __APPLE__
1960 typedef semaphore_t os_semaphore_t;
1961
1962 #define SEM_INIT(sem, value) semaphore_create(mach_task_self(), &sem, SYNC_POLICY_FIFO, value)
1963 #define SEM_WAIT(sem) semaphore_wait(sem)
1964 #define SEM_POST(sem) semaphore_signal(sem)
1965 #define SEM_DESTROY(sem) semaphore_destroy(mach_task_self(), sem)
1966 #else
1967 typedef sem_t os_semaphore_t;
1968
1969 #define SEM_INIT(sem, value) sem_init(&sem, 0, value)
1970 #define SEM_WAIT(sem) sem_wait(&sem)
1971 #define SEM_POST(sem) sem_post(&sem)
1972 #define SEM_DESTROY(sem) sem_destroy(&sem)
1973 #endif
1974
1975 #ifdef __APPLE__
1976 // OS X doesn't support unamed POSIX semaphores, so the implementation in os_posix.cpp can't be used.
1977
1978 static const char* sem_init_strerror(kern_return_t value) {
1979 switch (value) {
1980 case KERN_INVALID_ARGUMENT: return "Invalid argument";
1981 case KERN_RESOURCE_SHORTAGE: return "Resource shortage";
1982 default: return "Unknown";
1983 }
1984 }
1985
1986 OSXSemaphore::OSXSemaphore(uint value) {
1987 kern_return_t ret = SEM_INIT(_semaphore, value);
1988
1989 guarantee(ret == KERN_SUCCESS, "Failed to create semaphore: %s", sem_init_strerror(ret));
1990 }
1991
1992 OSXSemaphore::~OSXSemaphore() {
1993 SEM_DESTROY(_semaphore);
1994 }
1995
1996 void OSXSemaphore::signal(uint count) {
1997 for (uint i = 0; i < count; i++) {
1998 kern_return_t ret = SEM_POST(_semaphore);
1999
2000 assert(ret == KERN_SUCCESS, "Failed to signal semaphore");
2001 }
2002 }
2003
2004 void OSXSemaphore::wait() {
2005 kern_return_t ret;
2006 while ((ret = SEM_WAIT(_semaphore)) == KERN_ABORTED) {
2007 // Semaphore was interrupted. Retry.
2008 }
2009 assert(ret == KERN_SUCCESS, "Failed to wait on semaphore");
2010 }
2011
2012 jlong OSXSemaphore::currenttime() {
2013 struct timeval tv;
2014 gettimeofday(&tv, NULL);
2015 return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000);
2016 }
2017
2018 bool OSXSemaphore::trywait() {
2019 return timedwait(0, 0);
2020 }
2021
2022 bool OSXSemaphore::timedwait(unsigned int sec, int nsec) {
2023 kern_return_t kr = KERN_ABORTED;
2024 mach_timespec_t waitspec;
2025 waitspec.tv_sec = sec;
2026 waitspec.tv_nsec = nsec;
2027
2028 jlong starttime = currenttime();
2029
2030 kr = semaphore_timedwait(_semaphore, waitspec);
2031 while (kr == KERN_ABORTED) {
2032 jlong totalwait = (sec * NANOSECS_PER_SEC) + nsec;
2033
2034 jlong current = currenttime();
2035 jlong passedtime = current - starttime;
2036
2037 if (passedtime >= totalwait) {
2038 waitspec.tv_sec = 0;
2039 waitspec.tv_nsec = 0;
2040 } else {
2041 jlong waittime = totalwait - (current - starttime);
2042 waitspec.tv_sec = waittime / NANOSECS_PER_SEC;
2043 waitspec.tv_nsec = waittime % NANOSECS_PER_SEC;
2044 }
2045
2046 kr = semaphore_timedwait(_semaphore, waitspec);
2047 }
2048
2049 return kr == KERN_SUCCESS;
2050 }
2051
2052 #else
2053 // Use POSIX implementation of semaphores.
2054
2055 struct timespec PosixSemaphore::create_timespec(unsigned int sec, int nsec) {
2056 struct timespec ts;
2057 unpackTime(&ts, false, (sec * NANOSECS_PER_SEC) + nsec);
2058
2059 return ts;
2060 }
2061
2062 #endif // __APPLE__
2063
2064 static os_semaphore_t sig_sem;
2065
2066 #ifdef __APPLE__
2067 static OSXSemaphore sr_semaphore;
2068 #else
2069 static PosixSemaphore sr_semaphore;
2070 #endif
2071
2072 void os::signal_init_pd() {
2073 // Initialize signal structures
2074 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
2075
2076 // Initialize signal semaphore
2077 ::SEM_INIT(sig_sem, 0);
2078 }
2079
2080 void os::signal_notify(int sig) {
2081 Atomic::inc(&pending_signals[sig]);
2082 ::SEM_POST(sig_sem);
2083 }
2084
2085 static int check_pending_signals(bool wait) {
2086 Atomic::store(0, &sigint_count);
2087 for (;;) {
2088 for (int i = 0; i < NSIG + 1; i++) {
2089 jint n = pending_signals[i];
2090 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
2091 return i;
2092 }
2093 }
2094 if (!wait) {
2095 return -1;
2096 }
2097 JavaThread *thread = JavaThread::current();
2098 ThreadBlockInVM tbivm(thread);
2099
2100 bool threadIsSuspended;
2101 do {
2102 thread->set_suspend_equivalent();
2103 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
2104 ::SEM_WAIT(sig_sem);
2105
2106 // were we externally suspended while we were waiting?
2107 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
2108 if (threadIsSuspended) {
2109 // The semaphore has been incremented, but while we were waiting
2110 // another thread suspended us. We don't want to continue running
2111 // while suspended because that would surprise the thread that
2112 // suspended us.
2113 ::SEM_POST(sig_sem);
2114
2115 thread->java_suspend_self();
2116 }
2117 } while (threadIsSuspended);
2118 }
2119 }
2120
2121 int os::signal_lookup() {
2122 return check_pending_signals(false);
2123 }
2124
2125 int os::signal_wait() {
2126 return check_pending_signals(true);
2127 }
2128
2129 ////////////////////////////////////////////////////////////////////////////////
2130 // Virtual Memory
2131
2132 int os::vm_page_size() {
2133 // Seems redundant as all get out
2134 assert(os::Bsd::page_size() != -1, "must call os::init");
2135 return os::Bsd::page_size();
2136 }
2137
2138 // Solaris allocates memory by pages.
2139 int os::vm_allocation_granularity() {
2140 assert(os::Bsd::page_size() != -1, "must call os::init");
2141 return os::Bsd::page_size();
2142 }
2143
2144 // Rationale behind this function:
2145 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
2146 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
2147 // samples for JITted code. Here we create private executable mapping over the code cache
2148 // and then we can use standard (well, almost, as mapping can change) way to provide
2149 // info for the reporting script by storing timestamp and location of symbol
2150 void bsd_wrap_code(char* base, size_t size) {
2151 static volatile jint cnt = 0;
2152
2153 if (!UseOprofile) {
2154 return;
2155 }
2156
2157 char buf[PATH_MAX + 1];
2158 int num = Atomic::add(1, &cnt);
2159
2160 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
2161 os::get_temp_directory(), os::current_process_id(), num);
2162 unlink(buf);
2163
2164 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
2165
2166 if (fd != -1) {
2167 off_t rv = ::lseek(fd, size-2, SEEK_SET);
2168 if (rv != (off_t)-1) {
2169 if (::write(fd, "", 1) == 1) {
2170 mmap(base, size,
2171 PROT_READ|PROT_WRITE|PROT_EXEC,
2172 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
2173 }
2174 }
2175 ::close(fd);
2176 unlink(buf);
2177 }
2178 }
2179
2180 static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
2181 int err) {
2182 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT
2183 ", %d) failed; error='%s' (errno=%d)", addr, size, exec,
2184 strerror(err), err);
2185 }
2186
2187 // NOTE: Bsd kernel does not really reserve the pages for us.
2188 // All it does is to check if there are enough free pages
2189 // left at the time of mmap(). This could be a potential
2190 // problem.
2191 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
2192 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
2193 #ifdef __OpenBSD__
2194 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2195 if (::mprotect(addr, size, prot) == 0) {
2196 return true;
2197 }
2198 #else
2199 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
2200 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
2201 if (res != (uintptr_t) MAP_FAILED) {
2202 return true;
2203 }
2204 #endif
2205
2206 // Warn about any commit errors we see in non-product builds just
2207 // in case mmap() doesn't work as described on the man page.
2208 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);)
2209
2210 return false;
2211 }
2212
2213 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
2214 bool exec) {
2215 // alignment_hint is ignored on this OS
2216 return pd_commit_memory(addr, size, exec);
2217 }
2218
2219 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
2220 const char* mesg) {
2221 assert(mesg != NULL, "mesg must be specified");
2222 if (!pd_commit_memory(addr, size, exec)) {
2223 // add extra info in product mode for vm_exit_out_of_memory():
2224 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
2225 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, "%s", mesg);
2226 }
2227 }
2228
2229 void os::pd_commit_memory_or_exit(char* addr, size_t size,
2230 size_t alignment_hint, bool exec,
2231 const char* mesg) {
2232 // alignment_hint is ignored on this OS
2233 pd_commit_memory_or_exit(addr, size, exec, mesg);
2234 }
2235
2236 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
2237 }
2238
2239 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
2240 ::madvise(addr, bytes, MADV_DONTNEED);
2241 }
2242
2243 void os::numa_make_global(char *addr, size_t bytes) {
2244 }
2245
2246 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
2247 }
2248
2249 bool os::numa_topology_changed() { return false; }
2250
2251 size_t os::numa_get_groups_num() {
2252 return 1;
2253 }
2254
2255 int os::numa_get_group_id() {
2256 return 0;
2257 }
2258
2259 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
2260 if (size > 0) {
2261 ids[0] = 0;
2262 return 1;
2263 }
2264 return 0;
2265 }
2266
2267 bool os::get_page_info(char *start, page_info* info) {
2268 return false;
2269 }
2270
2271 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2272 return end;
2273 }
2274
2275
2276 bool os::pd_uncommit_memory(char* addr, size_t size) {
2277 #ifdef __OpenBSD__
2278 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2279 return ::mprotect(addr, size, PROT_NONE) == 0;
2280 #else
2281 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
2282 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
2283 return res != (uintptr_t) MAP_FAILED;
2284 #endif
2285 }
2286
2287 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2288 return os::commit_memory(addr, size, !ExecMem);
2289 }
2290
2291 // If this is a growable mapping, remove the guard pages entirely by
2292 // munmap()ping them. If not, just call uncommit_memory().
2293 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2294 return os::uncommit_memory(addr, size);
2295 }
2296
2297 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2298 // at 'requested_addr'. If there are existing memory mappings at the same
2299 // location, however, they will be overwritten. If 'fixed' is false,
2300 // 'requested_addr' is only treated as a hint, the return value may or
2301 // may not start from the requested address. Unlike Bsd mmap(), this
2302 // function returns NULL to indicate failure.
2303 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2304 char * addr;
2305 int flags;
2306
2307 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2308 if (fixed) {
2309 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2310 flags |= MAP_FIXED;
2311 }
2312
2313 // Map reserved/uncommitted pages PROT_NONE so we fail early if we
2314 // touch an uncommitted page. Otherwise, the read/write might
2315 // succeed if we have enough swap space to back the physical page.
2316 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE,
2317 flags, -1, 0);
2318
2319 return addr == MAP_FAILED ? NULL : addr;
2320 }
2321
2322 static int anon_munmap(char * addr, size_t size) {
2323 return ::munmap(addr, size) == 0;
2324 }
2325
2326 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
2327 size_t alignment_hint) {
2328 return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2329 }
2330
2331 bool os::pd_release_memory(char* addr, size_t size) {
2332 return anon_munmap(addr, size);
2333 }
2334
2335 static bool bsd_mprotect(char* addr, size_t size, int prot) {
2336 // Bsd wants the mprotect address argument to be page aligned.
2337 char* bottom = (char*)align_size_down((intptr_t)addr, os::Bsd::page_size());
2338
2339 // According to SUSv3, mprotect() should only be used with mappings
2340 // established by mmap(), and mmap() always maps whole pages. Unaligned
2341 // 'addr' likely indicates problem in the VM (e.g. trying to change
2342 // protection of malloc'ed or statically allocated memory). Check the
2343 // caller if you hit this assert.
2344 assert(addr == bottom, "sanity check");
2345
2346 size = align_size_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2347 return ::mprotect(bottom, size, prot) == 0;
2348 }
2349
2350 // Set protections specified
2351 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2352 bool is_committed) {
2353 unsigned int p = 0;
2354 switch (prot) {
2355 case MEM_PROT_NONE: p = PROT_NONE; break;
2356 case MEM_PROT_READ: p = PROT_READ; break;
2357 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
2358 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2359 default:
2360 ShouldNotReachHere();
2361 }
2362 // is_committed is unused.
2363 return bsd_mprotect(addr, bytes, p);
2364 }
2365
2366 bool os::guard_memory(char* addr, size_t size) {
2367 return bsd_mprotect(addr, size, PROT_NONE);
2368 }
2369
2370 bool os::unguard_memory(char* addr, size_t size) {
2371 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
2372 }
2373
2374 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
2375 return false;
2376 }
2377
2378 // Large page support
2379
2380 static size_t _large_page_size = 0;
2381
2382 void os::large_page_init() {
2383 }
2384
2385
2386 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) {
2387 fatal("This code is not used or maintained.");
2388
2389 // "exec" is passed in but not used. Creating the shared image for
2390 // the code cache doesn't have an SHM_X executable permission to check.
2391 assert(UseLargePages && UseSHM, "only for SHM large pages");
2392
2393 key_t key = IPC_PRIVATE;
2394 char *addr;
2395
2396 bool warn_on_failure = UseLargePages &&
2397 (!FLAG_IS_DEFAULT(UseLargePages) ||
2398 !FLAG_IS_DEFAULT(LargePageSizeInBytes));
2399
2400 // Create a large shared memory region to attach to based on size.
2401 // Currently, size is the total size of the heap
2402 int shmid = shmget(key, bytes, IPC_CREAT|SHM_R|SHM_W);
2403 if (shmid == -1) {
2404 // Possible reasons for shmget failure:
2405 // 1. shmmax is too small for Java heap.
2406 // > check shmmax value: cat /proc/sys/kernel/shmmax
2407 // > increase shmmax value: echo "0xffffffff" > /proc/sys/kernel/shmmax
2408 // 2. not enough large page memory.
2409 // > check available large pages: cat /proc/meminfo
2410 // > increase amount of large pages:
2411 // echo new_value > /proc/sys/vm/nr_hugepages
2412 // Note 1: different Bsd may use different name for this property,
2413 // e.g. on Redhat AS-3 it is "hugetlb_pool".
2414 // Note 2: it's possible there's enough physical memory available but
2415 // they are so fragmented after a long run that they can't
2416 // coalesce into large pages. Try to reserve large pages when
2417 // the system is still "fresh".
2418 if (warn_on_failure) {
2419 warning("Failed to reserve shared memory (errno = %d).", errno);
2420 }
2421 return NULL;
2422 }
2423
2424 // attach to the region
2425 addr = (char*)shmat(shmid, req_addr, 0);
2426 int err = errno;
2427
2428 // Remove shmid. If shmat() is successful, the actual shared memory segment
2429 // will be deleted when it's detached by shmdt() or when the process
2430 // terminates. If shmat() is not successful this will remove the shared
2431 // segment immediately.
2432 shmctl(shmid, IPC_RMID, NULL);
2433
2434 if ((intptr_t)addr == -1) {
2435 if (warn_on_failure) {
2436 warning("Failed to attach shared memory (errno = %d).", err);
2437 }
2438 return NULL;
2439 }
2440
2441 // The memory is committed
2442 MemTracker::record_virtual_memory_reserve_and_commit((address)addr, bytes, CALLER_PC);
2443
2444 return addr;
2445 }
2446
2447 bool os::release_memory_special(char* base, size_t bytes) {
2448 if (MemTracker::tracking_level() > NMT_minimal) {
2449 Tracker tkr = MemTracker::get_virtual_memory_release_tracker();
2450 // detaching the SHM segment will also delete it, see reserve_memory_special()
2451 int rslt = shmdt(base);
2452 if (rslt == 0) {
2453 tkr.record((address)base, bytes);
2454 return true;
2455 } else {
2456 return false;
2457 }
2458 } else {
2459 return shmdt(base) == 0;
2460 }
2461 }
2462
2463 size_t os::large_page_size() {
2464 return _large_page_size;
2465 }
2466
2467 // HugeTLBFS allows application to commit large page memory on demand;
2468 // with SysV SHM the entire memory region must be allocated as shared
2469 // memory.
2470 bool os::can_commit_large_page_memory() {
2471 return UseHugeTLBFS;
2472 }
2473
2474 bool os::can_execute_large_page_memory() {
2475 return UseHugeTLBFS;
2476 }
2477
2478 // Reserve memory at an arbitrary address, only if that area is
2479 // available (and not reserved for something else).
2480
2481 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2482 const int max_tries = 10;
2483 char* base[max_tries];
2484 size_t size[max_tries];
2485 const size_t gap = 0x000000;
2486
2487 // Assert only that the size is a multiple of the page size, since
2488 // that's all that mmap requires, and since that's all we really know
2489 // about at this low abstraction level. If we need higher alignment,
2490 // we can either pass an alignment to this method or verify alignment
2491 // in one of the methods further up the call chain. See bug 5044738.
2492 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2493
2494 // Repeatedly allocate blocks until the block is allocated at the
2495 // right spot.
2496
2497 // Bsd mmap allows caller to pass an address as hint; give it a try first,
2498 // if kernel honors the hint then we can return immediately.
2499 char * addr = anon_mmap(requested_addr, bytes, false);
2500 if (addr == requested_addr) {
2501 return requested_addr;
2502 }
2503
2504 if (addr != NULL) {
2505 // mmap() is successful but it fails to reserve at the requested address
2506 anon_munmap(addr, bytes);
2507 }
2508
2509 int i;
2510 for (i = 0; i < max_tries; ++i) {
2511 base[i] = reserve_memory(bytes);
2512
2513 if (base[i] != NULL) {
2514 // Is this the block we wanted?
2515 if (base[i] == requested_addr) {
2516 size[i] = bytes;
2517 break;
2518 }
2519
2520 // Does this overlap the block we wanted? Give back the overlapped
2521 // parts and try again.
2522
2523 size_t top_overlap = requested_addr + (bytes + gap) - base[i];
2524 if (top_overlap >= 0 && top_overlap < bytes) {
2525 unmap_memory(base[i], top_overlap);
2526 base[i] += top_overlap;
2527 size[i] = bytes - top_overlap;
2528 } else {
2529 size_t bottom_overlap = base[i] + bytes - requested_addr;
2530 if (bottom_overlap >= 0 && bottom_overlap < bytes) {
2531 unmap_memory(requested_addr, bottom_overlap);
2532 size[i] = bytes - bottom_overlap;
2533 } else {
2534 size[i] = bytes;
2535 }
2536 }
2537 }
2538 }
2539
2540 // Give back the unused reserved pieces.
2541
2542 for (int j = 0; j < i; ++j) {
2543 if (base[j] != NULL) {
2544 unmap_memory(base[j], size[j]);
2545 }
2546 }
2547
2548 if (i < max_tries) {
2549 return requested_addr;
2550 } else {
2551 return NULL;
2552 }
2553 }
2554
2555 size_t os::read(int fd, void *buf, unsigned int nBytes) {
2556 RESTARTABLE_RETURN_INT(::read(fd, buf, nBytes));
2557 }
2558
2559 size_t os::read_at(int fd, void *buf, unsigned int nBytes, jlong offset) {
2560 RESTARTABLE_RETURN_INT(::pread(fd, buf, nBytes, offset));
2561 }
2562
2563 void os::naked_short_sleep(jlong ms) {
2564 struct timespec req;
2565
2566 assert(ms < 1000, "Un-interruptable sleep, short time use only");
2567 req.tv_sec = 0;
2568 if (ms > 0) {
2569 req.tv_nsec = (ms % 1000) * 1000000;
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::naked_yield() {
2592 sched_yield();
2593 }
2594
2595 ////////////////////////////////////////////////////////////////////////////////
2596 // thread priority support
2597
2598 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2599 // only supports dynamic priority, static priority must be zero. For real-time
2600 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
2601 // However, for large multi-threaded applications, SCHED_RR is not only slower
2602 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2603 // of 5 runs - Sep 2005).
2604 //
2605 // The following code actually changes the niceness of kernel-thread/LWP. It
2606 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
2607 // not the entire user process, and user level threads are 1:1 mapped to kernel
2608 // threads. It has always been the case, but could change in the future. For
2609 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2610 // It is only used when ThreadPriorityPolicy=1 and requires root privilege.
2611
2612 #if !defined(__APPLE__)
2613 int os::java_to_os_priority[CriticalPriority + 1] = {
2614 19, // 0 Entry should never be used
2615
2616 0, // 1 MinPriority
2617 3, // 2
2618 6, // 3
2619
2620 10, // 4
2621 15, // 5 NormPriority
2622 18, // 6
2623
2624 21, // 7
2625 25, // 8
2626 28, // 9 NearMaxPriority
2627
2628 31, // 10 MaxPriority
2629
2630 31 // 11 CriticalPriority
2631 };
2632 #else
2633 // Using Mach high-level priority assignments
2634 int os::java_to_os_priority[CriticalPriority + 1] = {
2635 0, // 0 Entry should never be used (MINPRI_USER)
2636
2637 27, // 1 MinPriority
2638 28, // 2
2639 29, // 3
2640
2641 30, // 4
2642 31, // 5 NormPriority (BASEPRI_DEFAULT)
2643 32, // 6
2644
2645 33, // 7
2646 34, // 8
2647 35, // 9 NearMaxPriority
2648
2649 36, // 10 MaxPriority
2650
2651 36 // 11 CriticalPriority
2652 };
2653 #endif
2654
2655 static int prio_init() {
2656 if (ThreadPriorityPolicy == 1) {
2657 // Only root can raise thread priority. Don't allow ThreadPriorityPolicy=1
2658 // if effective uid is not root. Perhaps, a more elegant way of doing
2659 // this is to test CAP_SYS_NICE capability, but that will require libcap.so
2660 if (geteuid() != 0) {
2661 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy)) {
2662 warning("-XX:ThreadPriorityPolicy requires root privilege on Bsd");
2663 }
2664 ThreadPriorityPolicy = 0;
2665 }
2666 }
2667 if (UseCriticalJavaThreadPriority) {
2668 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2669 }
2670 return 0;
2671 }
2672
2673 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2674 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) return OS_OK;
2675
2676 #ifdef __OpenBSD__
2677 // OpenBSD pthread_setprio starves low priority threads
2678 return OS_OK;
2679 #elif defined(__FreeBSD__)
2680 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2681 #elif defined(__APPLE__) || defined(__NetBSD__)
2682 struct sched_param sp;
2683 int policy;
2684 pthread_t self = pthread_self();
2685
2686 if (pthread_getschedparam(self, &policy, &sp) != 0) {
2687 return OS_ERR;
2688 }
2689
2690 sp.sched_priority = newpri;
2691 if (pthread_setschedparam(self, policy, &sp) != 0) {
2692 return OS_ERR;
2693 }
2694
2695 return OS_OK;
2696 #else
2697 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2698 return (ret == 0) ? OS_OK : OS_ERR;
2699 #endif
2700 }
2701
2702 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2703 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) {
2704 *priority_ptr = java_to_os_priority[NormPriority];
2705 return OS_OK;
2706 }
2707
2708 errno = 0;
2709 #if defined(__OpenBSD__) || defined(__FreeBSD__)
2710 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2711 #elif defined(__APPLE__) || defined(__NetBSD__)
2712 int policy;
2713 struct sched_param sp;
2714
2715 pthread_getschedparam(pthread_self(), &policy, &sp);
2716 *priority_ptr = sp.sched_priority;
2717 #else
2718 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2719 #endif
2720 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2721 }
2722
2723 // Hint to the underlying OS that a task switch would not be good.
2724 // Void return because it's a hint and can fail.
2725 void os::hint_no_preempt() {}
2726
2727 ////////////////////////////////////////////////////////////////////////////////
2728 // suspend/resume support
2729
2730 // the low-level signal-based suspend/resume support is a remnant from the
2731 // old VM-suspension that used to be for java-suspension, safepoints etc,
2732 // within hotspot. Now there is a single use-case for this:
2733 // - calling get_thread_pc() on the VMThread by the flat-profiler task
2734 // that runs in the watcher thread.
2735 // The remaining code is greatly simplified from the more general suspension
2736 // code that used to be used.
2737 //
2738 // The protocol is quite simple:
2739 // - suspend:
2740 // - sends a signal to the target thread
2741 // - polls the suspend state of the osthread using a yield loop
2742 // - target thread signal handler (SR_handler) sets suspend state
2743 // and blocks in sigsuspend until continued
2744 // - resume:
2745 // - sets target osthread state to continue
2746 // - sends signal to end the sigsuspend loop in the SR_handler
2747 //
2748 // Note that the SR_lock plays no role in this suspend/resume protocol.
2749
2750 static void resume_clear_context(OSThread *osthread) {
2751 osthread->set_ucontext(NULL);
2752 osthread->set_siginfo(NULL);
2753 }
2754
2755 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2756 osthread->set_ucontext(context);
2757 osthread->set_siginfo(siginfo);
2758 }
2759
2760 // Handler function invoked when a thread's execution is suspended or
2761 // resumed. We have to be careful that only async-safe functions are
2762 // called here (Note: most pthread functions are not async safe and
2763 // should be avoided.)
2764 //
2765 // Note: sigwait() is a more natural fit than sigsuspend() from an
2766 // interface point of view, but sigwait() prevents the signal hander
2767 // from being run. libpthread would get very confused by not having
2768 // its signal handlers run and prevents sigwait()'s use with the
2769 // mutex granting granting signal.
2770 //
2771 // Currently only ever called on the VMThread or JavaThread
2772 //
2773 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2774 // Save and restore errno to avoid confusing native code with EINTR
2775 // after sigsuspend.
2776 int old_errno = errno;
2777
2778 Thread* thread = Thread::current();
2779 OSThread* osthread = thread->osthread();
2780 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
2781
2782 os::SuspendResume::State current = osthread->sr.state();
2783 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
2784 suspend_save_context(osthread, siginfo, context);
2785
2786 // attempt to switch the state, we assume we had a SUSPEND_REQUEST
2787 os::SuspendResume::State state = osthread->sr.suspended();
2788 if (state == os::SuspendResume::SR_SUSPENDED) {
2789 sigset_t suspend_set; // signals for sigsuspend()
2790
2791 // get current set of blocked signals and unblock resume signal
2792 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2793 sigdelset(&suspend_set, SR_signum);
2794
2795 sr_semaphore.signal();
2796 // wait here until we are resumed
2797 while (1) {
2798 sigsuspend(&suspend_set);
2799
2800 os::SuspendResume::State result = osthread->sr.running();
2801 if (result == os::SuspendResume::SR_RUNNING) {
2802 sr_semaphore.signal();
2803 break;
2804 } else if (result != os::SuspendResume::SR_SUSPENDED) {
2805 ShouldNotReachHere();
2806 }
2807 }
2808
2809 } else if (state == os::SuspendResume::SR_RUNNING) {
2810 // request was cancelled, continue
2811 } else {
2812 ShouldNotReachHere();
2813 }
2814
2815 resume_clear_context(osthread);
2816 } else if (current == os::SuspendResume::SR_RUNNING) {
2817 // request was cancelled, continue
2818 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
2819 // ignore
2820 } else {
2821 // ignore
2822 }
2823
2824 errno = old_errno;
2825 }
2826
2827
2828 static int SR_initialize() {
2829 struct sigaction act;
2830 char *s;
2831 // Get signal number to use for suspend/resume
2832 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2833 int sig = ::strtol(s, 0, 10);
2834 if (sig > 0 || sig < NSIG) {
2835 SR_signum = sig;
2836 }
2837 }
2838
2839 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2840 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2841
2842 sigemptyset(&SR_sigset);
2843 sigaddset(&SR_sigset, SR_signum);
2844
2845 // Set up signal handler for suspend/resume
2846 act.sa_flags = SA_RESTART|SA_SIGINFO;
2847 act.sa_handler = (void (*)(int)) SR_handler;
2848
2849 // SR_signum is blocked by default.
2850 // 4528190 - We also need to block pthread restart signal (32 on all
2851 // supported Bsd platforms). Note that BsdThreads need to block
2852 // this signal for all threads to work properly. So we don't have
2853 // to use hard-coded signal number when setting up the mask.
2854 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2855
2856 if (sigaction(SR_signum, &act, 0) == -1) {
2857 return -1;
2858 }
2859
2860 // Save signal flag
2861 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2862 return 0;
2863 }
2864
2865 static int sr_notify(OSThread* osthread) {
2866 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2867 assert_status(status == 0, status, "pthread_kill");
2868 return status;
2869 }
2870
2871 // "Randomly" selected value for how long we want to spin
2872 // before bailing out on suspending a thread, also how often
2873 // we send a signal to a thread we want to resume
2874 static const int RANDOMLY_LARGE_INTEGER = 1000000;
2875 static const int RANDOMLY_LARGE_INTEGER2 = 100;
2876
2877 // returns true on success and false on error - really an error is fatal
2878 // but this seems the normal response to library errors
2879 static bool do_suspend(OSThread* osthread) {
2880 assert(osthread->sr.is_running(), "thread should be running");
2881 assert(!sr_semaphore.trywait(), "semaphore has invalid state");
2882
2883 // mark as suspended and send signal
2884 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
2885 // failed to switch, state wasn't running?
2886 ShouldNotReachHere();
2887 return false;
2888 }
2889
2890 if (sr_notify(osthread) != 0) {
2891 ShouldNotReachHere();
2892 }
2893
2894 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
2895 while (true) {
2896 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2897 break;
2898 } else {
2899 // timeout
2900 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
2901 if (cancelled == os::SuspendResume::SR_RUNNING) {
2902 return false;
2903 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
2904 // make sure that we consume the signal on the semaphore as well
2905 sr_semaphore.wait();
2906 break;
2907 } else {
2908 ShouldNotReachHere();
2909 return false;
2910 }
2911 }
2912 }
2913
2914 guarantee(osthread->sr.is_suspended(), "Must be suspended");
2915 return true;
2916 }
2917
2918 static void do_resume(OSThread* osthread) {
2919 assert(osthread->sr.is_suspended(), "thread should be suspended");
2920 assert(!sr_semaphore.trywait(), "invalid semaphore state");
2921
2922 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
2923 // failed to switch to WAKEUP_REQUEST
2924 ShouldNotReachHere();
2925 return;
2926 }
2927
2928 while (true) {
2929 if (sr_notify(osthread) == 0) {
2930 if (sr_semaphore.timedwait(0, 2 * NANOSECS_PER_MILLISEC)) {
2931 if (osthread->sr.is_running()) {
2932 return;
2933 }
2934 }
2935 } else {
2936 ShouldNotReachHere();
2937 }
2938 }
2939
2940 guarantee(osthread->sr.is_running(), "Must be running!");
2941 }
2942
2943 ///////////////////////////////////////////////////////////////////////////////////
2944 // signal handling (except suspend/resume)
2945
2946 // This routine may be used by user applications as a "hook" to catch signals.
2947 // The user-defined signal handler must pass unrecognized signals to this
2948 // routine, and if it returns true (non-zero), then the signal handler must
2949 // return immediately. If the flag "abort_if_unrecognized" is true, then this
2950 // routine will never retun false (zero), but instead will execute a VM panic
2951 // routine kill the process.
2952 //
2953 // If this routine returns false, it is OK to call it again. This allows
2954 // the user-defined signal handler to perform checks either before or after
2955 // the VM performs its own checks. Naturally, the user code would be making
2956 // a serious error if it tried to handle an exception (such as a null check
2957 // or breakpoint) that the VM was generating for its own correct operation.
2958 //
2959 // This routine may recognize any of the following kinds of signals:
2960 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
2961 // It should be consulted by handlers for any of those signals.
2962 //
2963 // The caller of this routine must pass in the three arguments supplied
2964 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
2965 // field of the structure passed to sigaction(). This routine assumes that
2966 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
2967 //
2968 // Note that the VM will print warnings if it detects conflicting signal
2969 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
2970 //
2971 extern "C" JNIEXPORT int JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
2972 void* ucontext,
2973 int abort_if_unrecognized);
2974
2975 void signalHandler(int sig, siginfo_t* info, void* uc) {
2976 assert(info != NULL && uc != NULL, "it must be old kernel");
2977 int orig_errno = errno; // Preserve errno value over signal handler.
2978 JVM_handle_bsd_signal(sig, info, uc, true);
2979 errno = orig_errno;
2980 }
2981
2982
2983 // This boolean allows users to forward their own non-matching signals
2984 // to JVM_handle_bsd_signal, harmlessly.
2985 bool os::Bsd::signal_handlers_are_installed = false;
2986
2987 // For signal-chaining
2988 struct sigaction os::Bsd::sigact[MAXSIGNUM];
2989 unsigned int os::Bsd::sigs = 0;
2990 bool os::Bsd::libjsig_is_loaded = false;
2991 typedef struct sigaction *(*get_signal_t)(int);
2992 get_signal_t os::Bsd::get_signal_action = NULL;
2993
2994 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
2995 struct sigaction *actp = NULL;
2996
2997 if (libjsig_is_loaded) {
2998 // Retrieve the old signal handler from libjsig
2999 actp = (*get_signal_action)(sig);
3000 }
3001 if (actp == NULL) {
3002 // Retrieve the preinstalled signal handler from jvm
3003 actp = get_preinstalled_handler(sig);
3004 }
3005
3006 return actp;
3007 }
3008
3009 static bool call_chained_handler(struct sigaction *actp, int sig,
3010 siginfo_t *siginfo, void *context) {
3011 // Call the old signal handler
3012 if (actp->sa_handler == SIG_DFL) {
3013 // It's more reasonable to let jvm treat it as an unexpected exception
3014 // instead of taking the default action.
3015 return false;
3016 } else if (actp->sa_handler != SIG_IGN) {
3017 if ((actp->sa_flags & SA_NODEFER) == 0) {
3018 // automaticlly block the signal
3019 sigaddset(&(actp->sa_mask), sig);
3020 }
3021
3022 sa_handler_t hand;
3023 sa_sigaction_t sa;
3024 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
3025 // retrieve the chained handler
3026 if (siginfo_flag_set) {
3027 sa = actp->sa_sigaction;
3028 } else {
3029 hand = actp->sa_handler;
3030 }
3031
3032 if ((actp->sa_flags & SA_RESETHAND) != 0) {
3033 actp->sa_handler = SIG_DFL;
3034 }
3035
3036 // try to honor the signal mask
3037 sigset_t oset;
3038 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
3039
3040 // call into the chained handler
3041 if (siginfo_flag_set) {
3042 (*sa)(sig, siginfo, context);
3043 } else {
3044 (*hand)(sig);
3045 }
3046
3047 // restore the signal mask
3048 pthread_sigmask(SIG_SETMASK, &oset, 0);
3049 }
3050 // Tell jvm's signal handler the signal is taken care of.
3051 return true;
3052 }
3053
3054 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
3055 bool chained = false;
3056 // signal-chaining
3057 if (UseSignalChaining) {
3058 struct sigaction *actp = get_chained_signal_action(sig);
3059 if (actp != NULL) {
3060 chained = call_chained_handler(actp, sig, siginfo, context);
3061 }
3062 }
3063 return chained;
3064 }
3065
3066 struct sigaction* os::Bsd::get_preinstalled_handler(int sig) {
3067 if ((((unsigned int)1 << sig) & sigs) != 0) {
3068 return &sigact[sig];
3069 }
3070 return NULL;
3071 }
3072
3073 void os::Bsd::save_preinstalled_handler(int sig, struct sigaction& oldAct) {
3074 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3075 sigact[sig] = oldAct;
3076 sigs |= (unsigned int)1 << sig;
3077 }
3078
3079 // for diagnostic
3080 int os::Bsd::sigflags[MAXSIGNUM];
3081
3082 int os::Bsd::get_our_sigflags(int sig) {
3083 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3084 return sigflags[sig];
3085 }
3086
3087 void os::Bsd::set_our_sigflags(int sig, int flags) {
3088 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3089 sigflags[sig] = flags;
3090 }
3091
3092 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
3093 // Check for overwrite.
3094 struct sigaction oldAct;
3095 sigaction(sig, (struct sigaction*)NULL, &oldAct);
3096
3097 void* oldhand = oldAct.sa_sigaction
3098 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3099 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3100 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
3101 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
3102 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
3103 if (AllowUserSignalHandlers || !set_installed) {
3104 // Do not overwrite; user takes responsibility to forward to us.
3105 return;
3106 } else if (UseSignalChaining) {
3107 // save the old handler in jvm
3108 save_preinstalled_handler(sig, oldAct);
3109 // libjsig also interposes the sigaction() call below and saves the
3110 // old sigaction on it own.
3111 } else {
3112 fatal("Encountered unexpected pre-existing sigaction handler "
3113 "%#lx for signal %d.", (long)oldhand, sig);
3114 }
3115 }
3116
3117 struct sigaction sigAct;
3118 sigfillset(&(sigAct.sa_mask));
3119 sigAct.sa_handler = SIG_DFL;
3120 if (!set_installed) {
3121 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3122 } else {
3123 sigAct.sa_sigaction = signalHandler;
3124 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
3125 }
3126 #ifdef __APPLE__
3127 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV
3128 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages"
3129 // if the signal handler declares it will handle it on alternate stack.
3130 // Notice we only declare we will handle it on alt stack, but we are not
3131 // actually going to use real alt stack - this is just a workaround.
3132 // Please see ux_exception.c, method catch_mach_exception_raise for details
3133 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c
3134 if (sig == SIGSEGV) {
3135 sigAct.sa_flags |= SA_ONSTACK;
3136 }
3137 #endif
3138
3139 // Save flags, which are set by ours
3140 assert(sig > 0 && sig < MAXSIGNUM, "vm signal out of expected range");
3141 sigflags[sig] = sigAct.sa_flags;
3142
3143 int ret = sigaction(sig, &sigAct, &oldAct);
3144 assert(ret == 0, "check");
3145
3146 void* oldhand2 = oldAct.sa_sigaction
3147 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
3148 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
3149 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
3150 }
3151
3152 // install signal handlers for signals that HotSpot needs to
3153 // handle in order to support Java-level exception handling.
3154
3155 void os::Bsd::install_signal_handlers() {
3156 if (!signal_handlers_are_installed) {
3157 signal_handlers_are_installed = true;
3158
3159 // signal-chaining
3160 typedef void (*signal_setting_t)();
3161 signal_setting_t begin_signal_setting = NULL;
3162 signal_setting_t end_signal_setting = NULL;
3163 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3164 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
3165 if (begin_signal_setting != NULL) {
3166 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
3167 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
3168 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
3169 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
3170 libjsig_is_loaded = true;
3171 assert(UseSignalChaining, "should enable signal-chaining");
3172 }
3173 if (libjsig_is_loaded) {
3174 // Tell libjsig jvm is setting signal handlers
3175 (*begin_signal_setting)();
3176 }
3177
3178 set_signal_handler(SIGSEGV, true);
3179 set_signal_handler(SIGPIPE, true);
3180 set_signal_handler(SIGBUS, true);
3181 set_signal_handler(SIGILL, true);
3182 set_signal_handler(SIGFPE, true);
3183 set_signal_handler(SIGXFSZ, true);
3184
3185 #if defined(__APPLE__)
3186 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
3187 // signals caught and handled by the JVM. To work around this, we reset the mach task
3188 // signal handler that's placed on our process by CrashReporter. This disables
3189 // CrashReporter-based reporting.
3190 //
3191 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
3192 // on caught fatal signals.
3193 //
3194 // Additionally, gdb installs both standard BSD signal handlers, and mach exception
3195 // handlers. By replacing the existing task exception handler, we disable gdb's mach
3196 // exception handling, while leaving the standard BSD signal handlers functional.
3197 kern_return_t kr;
3198 kr = task_set_exception_ports(mach_task_self(),
3199 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
3200 MACH_PORT_NULL,
3201 EXCEPTION_STATE_IDENTITY,
3202 MACHINE_THREAD_STATE);
3203
3204 assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
3205 #endif
3206
3207 if (libjsig_is_loaded) {
3208 // Tell libjsig jvm finishes setting signal handlers
3209 (*end_signal_setting)();
3210 }
3211
3212 // We don't activate signal checker if libjsig is in place, we trust ourselves
3213 // and if UserSignalHandler is installed all bets are off
3214 if (CheckJNICalls) {
3215 if (libjsig_is_loaded) {
3216 if (PrintJNIResolving) {
3217 tty->print_cr("Info: libjsig is activated, all active signal checking is disabled");
3218 }
3219 check_signals = false;
3220 }
3221 if (AllowUserSignalHandlers) {
3222 if (PrintJNIResolving) {
3223 tty->print_cr("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
3224 }
3225 check_signals = false;
3226 }
3227 }
3228 }
3229 }
3230
3231
3232 /////
3233 // glibc on Bsd platform uses non-documented flag
3234 // to indicate, that some special sort of signal
3235 // trampoline is used.
3236 // We will never set this flag, and we should
3237 // ignore this flag in our diagnostic
3238 #ifdef SIGNIFICANT_SIGNAL_MASK
3239 #undef SIGNIFICANT_SIGNAL_MASK
3240 #endif
3241 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
3242
3243 static const char* get_signal_handler_name(address handler,
3244 char* buf, int buflen) {
3245 int offset;
3246 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
3247 if (found) {
3248 // skip directory names
3249 const char *p1, *p2;
3250 p1 = buf;
3251 size_t len = strlen(os::file_separator());
3252 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
3253 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
3254 } else {
3255 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
3256 }
3257 return buf;
3258 }
3259
3260 static void print_signal_handler(outputStream* st, int sig,
3261 char* buf, size_t buflen) {
3262 struct sigaction sa;
3263
3264 sigaction(sig, NULL, &sa);
3265
3266 // See comment for SIGNIFICANT_SIGNAL_MASK define
3267 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3268
3269 st->print("%s: ", os::exception_name(sig, buf, buflen));
3270
3271 address handler = (sa.sa_flags & SA_SIGINFO)
3272 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
3273 : CAST_FROM_FN_PTR(address, sa.sa_handler);
3274
3275 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
3276 st->print("SIG_DFL");
3277 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
3278 st->print("SIG_IGN");
3279 } else {
3280 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
3281 }
3282
3283 st->print(", sa_mask[0]=");
3284 os::Posix::print_signal_set_short(st, &sa.sa_mask);
3285
3286 address rh = VMError::get_resetted_sighandler(sig);
3287 // May be, handler was resetted by VMError?
3288 if (rh != NULL) {
3289 handler = rh;
3290 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
3291 }
3292
3293 st->print(", sa_flags=");
3294 os::Posix::print_sa_flags(st, sa.sa_flags);
3295
3296 // Check: is it our handler?
3297 if (handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
3298 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
3299 // It is our signal handler
3300 // check for flags, reset system-used one!
3301 if ((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3302 st->print(
3303 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
3304 os::Bsd::get_our_sigflags(sig));
3305 }
3306 }
3307 st->cr();
3308 }
3309
3310
3311 #define DO_SIGNAL_CHECK(sig) \
3312 do { \
3313 if (!sigismember(&check_signal_done, sig)) { \
3314 os::Bsd::check_signal_handler(sig); \
3315 } \
3316 } while (0)
3317
3318 // This method is a periodic task to check for misbehaving JNI applications
3319 // under CheckJNI, we can add any periodic checks here
3320
3321 void os::run_periodic_checks() {
3322
3323 if (check_signals == false) return;
3324
3325 // SEGV and BUS if overridden could potentially prevent
3326 // generation of hs*.log in the event of a crash, debugging
3327 // such a case can be very challenging, so we absolutely
3328 // check the following for a good measure:
3329 DO_SIGNAL_CHECK(SIGSEGV);
3330 DO_SIGNAL_CHECK(SIGILL);
3331 DO_SIGNAL_CHECK(SIGFPE);
3332 DO_SIGNAL_CHECK(SIGBUS);
3333 DO_SIGNAL_CHECK(SIGPIPE);
3334 DO_SIGNAL_CHECK(SIGXFSZ);
3335
3336
3337 // ReduceSignalUsage allows the user to override these handlers
3338 // see comments at the very top and jvm_solaris.h
3339 if (!ReduceSignalUsage) {
3340 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
3341 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
3342 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
3343 DO_SIGNAL_CHECK(BREAK_SIGNAL);
3344 }
3345
3346 DO_SIGNAL_CHECK(SR_signum);
3347 }
3348
3349 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
3350
3351 static os_sigaction_t os_sigaction = NULL;
3352
3353 void os::Bsd::check_signal_handler(int sig) {
3354 char buf[O_BUFLEN];
3355 address jvmHandler = NULL;
3356
3357
3358 struct sigaction act;
3359 if (os_sigaction == NULL) {
3360 // only trust the default sigaction, in case it has been interposed
3361 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
3362 if (os_sigaction == NULL) return;
3363 }
3364
3365 os_sigaction(sig, (struct sigaction*)NULL, &act);
3366
3367
3368 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3369
3370 address thisHandler = (act.sa_flags & SA_SIGINFO)
3371 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3372 : CAST_FROM_FN_PTR(address, act.sa_handler);
3373
3374
3375 switch (sig) {
3376 case SIGSEGV:
3377 case SIGBUS:
3378 case SIGFPE:
3379 case SIGPIPE:
3380 case SIGILL:
3381 case SIGXFSZ:
3382 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
3383 break;
3384
3385 case SHUTDOWN1_SIGNAL:
3386 case SHUTDOWN2_SIGNAL:
3387 case SHUTDOWN3_SIGNAL:
3388 case BREAK_SIGNAL:
3389 jvmHandler = (address)user_handler();
3390 break;
3391
3392 default:
3393 if (sig == SR_signum) {
3394 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3395 } else {
3396 return;
3397 }
3398 break;
3399 }
3400
3401 if (thisHandler != jvmHandler) {
3402 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3403 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3404 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3405 // No need to check this sig any longer
3406 sigaddset(&check_signal_done, sig);
3407 // Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN
3408 if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) {
3409 tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell",
3410 exception_name(sig, buf, O_BUFLEN));
3411 }
3412 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3413 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3414 tty->print("expected:" PTR32_FORMAT, os::Bsd::get_our_sigflags(sig));
3415 tty->print_cr(" found:" PTR32_FORMAT, act.sa_flags);
3416 // No need to check this sig any longer
3417 sigaddset(&check_signal_done, sig);
3418 }
3419
3420 // Dump all the signal
3421 if (sigismember(&check_signal_done, sig)) {
3422 print_signal_handlers(tty, buf, O_BUFLEN);
3423 }
3424 }
3425
3426 extern void report_error(char* file_name, int line_no, char* title,
3427 char* format, ...);
3428
3429 extern bool signal_name(int signo, char* buf, size_t len);
3430
3431 const char* os::exception_name(int exception_code, char* buf, size_t size) {
3432 if (0 < exception_code && exception_code <= SIGRTMAX) {
3433 // signal
3434 if (!signal_name(exception_code, buf, size)) {
3435 jio_snprintf(buf, size, "SIG%d", exception_code);
3436 }
3437 return buf;
3438 } else {
3439 return NULL;
3440 }
3441 }
3442
3443 // this is called _before_ the most of global arguments have been parsed
3444 void os::init(void) {
3445 char dummy; // used to get a guess on initial stack address
3446 // first_hrtime = gethrtime();
3447
3448 // With BsdThreads the JavaMain thread pid (primordial thread)
3449 // is different than the pid of the java launcher thread.
3450 // So, on Bsd, the launcher thread pid is passed to the VM
3451 // via the sun.java.launcher.pid property.
3452 // Use this property instead of getpid() if it was correctly passed.
3453 // See bug 6351349.
3454 pid_t java_launcher_pid = (pid_t) Arguments::sun_java_launcher_pid();
3455
3456 _initial_pid = (java_launcher_pid > 0) ? java_launcher_pid : getpid();
3457
3458 clock_tics_per_sec = CLK_TCK;
3459
3460 init_random(1234567);
3461
3462 ThreadCritical::initialize();
3463
3464 Bsd::set_page_size(getpagesize());
3465 if (Bsd::page_size() == -1) {
3466 fatal("os_bsd.cpp: os::init: sysconf failed (%s)", strerror(errno));
3467 }
3468 init_page_sizes((size_t) Bsd::page_size());
3469
3470 Bsd::initialize_system_info();
3471
3472 // main_thread points to the aboriginal thread
3473 Bsd::_main_thread = pthread_self();
3474
3475 Bsd::clock_init();
3476 initial_time_count = javaTimeNanos();
3477
3478 #ifdef __APPLE__
3479 // XXXDARWIN
3480 // Work around the unaligned VM callbacks in hotspot's
3481 // sharedRuntime. The callbacks don't use SSE2 instructions, and work on
3482 // Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces
3483 // alignment when doing symbol lookup. To work around this, we force early
3484 // binding of all symbols now, thus binding when alignment is known-good.
3485 _dyld_bind_fully_image_containing_address((const void *) &os::init);
3486 #endif
3487 }
3488
3489 // To install functions for atexit system call
3490 extern "C" {
3491 static void perfMemory_exit_helper() {
3492 perfMemory_exit();
3493 }
3494 }
3495
3496 // this is called _after_ the global arguments have been parsed
3497 jint os::init_2(void) {
3498 // Allocate a single page and mark it as readable for safepoint polling
3499 address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3500 guarantee(polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page");
3501
3502 os::set_polling_page(polling_page);
3503
3504 #ifndef PRODUCT
3505 if (Verbose && PrintMiscellaneous) {
3506 tty->print("[SafePoint Polling address: " INTPTR_FORMAT "]\n",
3507 (intptr_t)polling_page);
3508 }
3509 #endif
3510
3511 if (!UseMembar) {
3512 address mem_serialize_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ | PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
3513 guarantee(mem_serialize_page != MAP_FAILED, "mmap Failed for memory serialize page");
3514 os::set_memory_serialize_page(mem_serialize_page);
3515
3516 #ifndef PRODUCT
3517 if (Verbose && PrintMiscellaneous) {
3518 tty->print("[Memory Serialize Page address: " INTPTR_FORMAT "]\n",
3519 (intptr_t)mem_serialize_page);
3520 }
3521 #endif
3522 }
3523
3524 // initialize suspend/resume support - must do this before signal_sets_init()
3525 if (SR_initialize() != 0) {
3526 perror("SR_initialize failed");
3527 return JNI_ERR;
3528 }
3529
3530 Bsd::signal_sets_init();
3531 Bsd::install_signal_handlers();
3532
3533 // Check minimum allowable stack size for thread creation and to initialize
3534 // the java system classes, including StackOverflowError - depends on page
3535 // size. Add a page for compiler2 recursion in main thread.
3536 // Add in 2*BytesPerWord times page size to account for VM stack during
3537 // class initialization depending on 32 or 64 bit VM.
3538 os::Bsd::min_stack_allowed = MAX2(os::Bsd::min_stack_allowed,
3539 (size_t)(StackYellowPages+StackRedPages+StackShadowPages+
3540 2*BytesPerWord COMPILER2_PRESENT(+1)) * Bsd::page_size());
3541
3542 size_t threadStackSizeInBytes = ThreadStackSize * K;
3543 if (threadStackSizeInBytes != 0 &&
3544 threadStackSizeInBytes < os::Bsd::min_stack_allowed) {
3545 tty->print_cr("\nThe stack size specified is too small, "
3546 "Specify at least %dk",
3547 os::Bsd::min_stack_allowed/ K);
3548 return JNI_ERR;
3549 }
3550
3551 // Make the stack size a multiple of the page size so that
3552 // the yellow/red zones can be guarded.
3553 JavaThread::set_stack_size_at_create(round_to(threadStackSizeInBytes,
3554 vm_page_size()));
3555
3556 if (MaxFDLimit) {
3557 // set the number of file descriptors to max. print out error
3558 // if getrlimit/setrlimit fails but continue regardless.
3559 struct rlimit nbr_files;
3560 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3561 if (status != 0) {
3562 if (PrintMiscellaneous && (Verbose || WizardMode)) {
3563 perror("os::init_2 getrlimit failed");
3564 }
3565 } else {
3566 nbr_files.rlim_cur = nbr_files.rlim_max;
3567
3568 #ifdef __APPLE__
3569 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3570 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3571 // be used instead
3572 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3573 #endif
3574
3575 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3576 if (status != 0) {
3577 if (PrintMiscellaneous && (Verbose || WizardMode)) {
3578 perror("os::init_2 setrlimit failed");
3579 }
3580 }
3581 }
3582 }
3583
3584 // at-exit methods are called in the reverse order of their registration.
3585 // atexit functions are called on return from main or as a result of a
3586 // call to exit(3C). There can be only 32 of these functions registered
3587 // and atexit() does not set errno.
3588
3589 if (PerfAllowAtExitRegistration) {
3590 // only register atexit functions if PerfAllowAtExitRegistration is set.
3591 // atexit functions can be delayed until process exit time, which
3592 // can be problematic for embedded VM situations. Embedded VMs should
3593 // call DestroyJavaVM() to assure that VM resources are released.
3594
3595 // note: perfMemory_exit_helper atexit function may be removed in
3596 // the future if the appropriate cleanup code can be added to the
3597 // VM_Exit VMOperation's doit method.
3598 if (atexit(perfMemory_exit_helper) != 0) {
3599 warning("os::init2 atexit(perfMemory_exit_helper) failed");
3600 }
3601 }
3602
3603 // initialize thread priority policy
3604 prio_init();
3605
3606 #ifdef __APPLE__
3607 // dynamically link to objective c gc registration
3608 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3609 if (handleLibObjc != NULL) {
3610 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3611 }
3612 #endif
3613
3614 return JNI_OK;
3615 }
3616
3617 // Mark the polling page as unreadable
3618 void os::make_polling_page_unreadable(void) {
3619 if (!guard_memory((char*)_polling_page, Bsd::page_size())) {
3620 fatal("Could not disable polling page");
3621 }
3622 }
3623
3624 // Mark the polling page as readable
3625 void os::make_polling_page_readable(void) {
3626 if (!bsd_mprotect((char *)_polling_page, Bsd::page_size(), PROT_READ)) {
3627 fatal("Could not enable polling page");
3628 }
3629 }
3630
3631 int os::active_processor_count() {
3632 return _processor_count;
3633 }
3634
3635 void os::set_native_thread_name(const char *name) {
3636 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3637 // This is only supported in Snow Leopard and beyond
3638 if (name != NULL) {
3639 // Add a "Java: " prefix to the name
3640 char buf[MAXTHREADNAMESIZE];
3641 snprintf(buf, sizeof(buf), "Java: %s", name);
3642 pthread_setname_np(buf);
3643 }
3644 #endif
3645 }
3646
3647 bool os::distribute_processes(uint length, uint* distribution) {
3648 // Not yet implemented.
3649 return false;
3650 }
3651
3652 bool os::bind_to_processor(uint processor_id) {
3653 // Not yet implemented.
3654 return false;
3655 }
3656
3657 void os::SuspendedThreadTask::internal_do_task() {
3658 if (do_suspend(_thread->osthread())) {
3659 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
3660 do_task(context);
3661 do_resume(_thread->osthread());
3662 }
3663 }
3664
3665 ///
3666 class PcFetcher : public os::SuspendedThreadTask {
3667 public:
3668 PcFetcher(Thread* thread) : os::SuspendedThreadTask(thread) {}
3669 ExtendedPC result();
3670 protected:
3671 void do_task(const os::SuspendedThreadTaskContext& context);
3672 private:
3673 ExtendedPC _epc;
3674 };
3675
3676 ExtendedPC PcFetcher::result() {
3677 guarantee(is_done(), "task is not done yet.");
3678 return _epc;
3679 }
3680
3681 void PcFetcher::do_task(const os::SuspendedThreadTaskContext& context) {
3682 Thread* thread = context.thread();
3683 OSThread* osthread = thread->osthread();
3684 if (osthread->ucontext() != NULL) {
3685 _epc = os::Bsd::ucontext_get_pc((ucontext_t *) context.ucontext());
3686 } else {
3687 // NULL context is unexpected, double-check this is the VMThread
3688 guarantee(thread->is_VM_thread(), "can only be called for VMThread");
3689 }
3690 }
3691
3692 // Suspends the target using the signal mechanism and then grabs the PC before
3693 // resuming the target. Used by the flat-profiler only
3694 ExtendedPC os::get_thread_pc(Thread* thread) {
3695 // Make sure that it is called by the watcher for the VMThread
3696 assert(Thread::current()->is_Watcher_thread(), "Must be watcher");
3697 assert(thread->is_VM_thread(), "Can only be called for VMThread");
3698
3699 PcFetcher fetcher(thread);
3700 fetcher.run();
3701 return fetcher.result();
3702 }
3703
3704 ////////////////////////////////////////////////////////////////////////////////
3705 // debug support
3706
3707 bool os::find(address addr, outputStream* st) {
3708 Dl_info dlinfo;
3709 memset(&dlinfo, 0, sizeof(dlinfo));
3710 if (dladdr(addr, &dlinfo) != 0) {
3711 st->print(PTR_FORMAT ": ", addr);
3712 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) {
3713 st->print("%s+%#x", dlinfo.dli_sname,
3714 addr - (intptr_t)dlinfo.dli_saddr);
3715 } else if (dlinfo.dli_fbase != NULL) {
3716 st->print("<offset %#x>", addr - (intptr_t)dlinfo.dli_fbase);
3717 } else {
3718 st->print("<absolute address>");
3719 }
3720 if (dlinfo.dli_fname != NULL) {
3721 st->print(" in %s", dlinfo.dli_fname);
3722 }
3723 if (dlinfo.dli_fbase != NULL) {
3724 st->print(" at " PTR_FORMAT, dlinfo.dli_fbase);
3725 }
3726 st->cr();
3727
3728 if (Verbose) {
3729 // decode some bytes around the PC
3730 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
3731 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size());
3732 address lowest = (address) dlinfo.dli_sname;
3733 if (!lowest) lowest = (address) dlinfo.dli_fbase;
3734 if (begin < lowest) begin = lowest;
3735 Dl_info dlinfo2;
3736 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr
3737 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) {
3738 end = (address) dlinfo2.dli_saddr;
3739 }
3740 Disassembler::decode(begin, end, st);
3741 }
3742 return true;
3743 }
3744 return false;
3745 }
3746
3747 ////////////////////////////////////////////////////////////////////////////////
3748 // misc
3749
3750 // This does not do anything on Bsd. This is basically a hook for being
3751 // able to use structured exception handling (thread-local exception filters)
3752 // on, e.g., Win32.
3753 void os::os_exception_wrapper(java_call_t f, JavaValue* value,
3754 const methodHandle& method, JavaCallArguments* args,
3755 Thread* thread) {
3756 f(value, method, args, thread);
3757 }
3758
3759 void os::print_statistics() {
3760 }
3761
3762 int os::message_box(const char* title, const char* message) {
3763 int i;
3764 fdStream err(defaultStream::error_fd());
3765 for (i = 0; i < 78; i++) err.print_raw("=");
3766 err.cr();
3767 err.print_raw_cr(title);
3768 for (i = 0; i < 78; i++) err.print_raw("-");
3769 err.cr();
3770 err.print_raw_cr(message);
3771 for (i = 0; i < 78; i++) err.print_raw("=");
3772 err.cr();
3773
3774 char buf[16];
3775 // Prevent process from exiting upon "read error" without consuming all CPU
3776 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3777
3778 return buf[0] == 'y' || buf[0] == 'Y';
3779 }
3780
3781 int os::stat(const char *path, struct stat *sbuf) {
3782 char pathbuf[MAX_PATH];
3783 if (strlen(path) > MAX_PATH - 1) {
3784 errno = ENAMETOOLONG;
3785 return -1;
3786 }
3787 os::native_path(strcpy(pathbuf, path));
3788 return ::stat(pathbuf, sbuf);
3789 }
3790
3791 bool os::check_heap(bool force) {
3792 return true;
3793 }
3794
3795 // Is a (classpath) directory empty?
3796 bool os::dir_is_empty(const char* path) {
3797 DIR *dir = NULL;
3798 struct dirent *ptr;
3799
3800 dir = opendir(path);
3801 if (dir == NULL) return true;
3802
3803 // Scan the directory
3804 bool result = true;
3805 char buf[sizeof(struct dirent) + MAX_PATH];
3806 while (result && (ptr = ::readdir(dir)) != NULL) {
3807 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3808 result = false;
3809 }
3810 }
3811 closedir(dir);
3812 return result;
3813 }
3814
3815 // This code originates from JDK's sysOpen and open64_w
3816 // from src/solaris/hpi/src/system_md.c
3817
3818 int os::open(const char *path, int oflag, int mode) {
3819 if (strlen(path) > MAX_PATH - 1) {
3820 errno = ENAMETOOLONG;
3821 return -1;
3822 }
3823 int fd;
3824
3825 fd = ::open(path, oflag, mode);
3826 if (fd == -1) return -1;
3827
3828 // If the open succeeded, the file might still be a directory
3829 {
3830 struct stat buf;
3831 int ret = ::fstat(fd, &buf);
3832 int st_mode = buf.st_mode;
3833
3834 if (ret != -1) {
3835 if ((st_mode & S_IFMT) == S_IFDIR) {
3836 errno = EISDIR;
3837 ::close(fd);
3838 return -1;
3839 }
3840 } else {
3841 ::close(fd);
3842 return -1;
3843 }
3844 }
3845
3846 // All file descriptors that are opened in the JVM and not
3847 // specifically destined for a subprocess should have the
3848 // close-on-exec flag set. If we don't set it, then careless 3rd
3849 // party native code might fork and exec without closing all
3850 // appropriate file descriptors (e.g. as we do in closeDescriptors in
3851 // UNIXProcess.c), and this in turn might:
3852 //
3853 // - cause end-of-file to fail to be detected on some file
3854 // descriptors, resulting in mysterious hangs, or
3855 //
3856 // - might cause an fopen in the subprocess to fail on a system
3857 // suffering from bug 1085341.
3858 //
3859 // (Yes, the default setting of the close-on-exec flag is a Unix
3860 // design flaw)
3861 //
3862 // See:
3863 // 1085341: 32-bit stdio routines should support file descriptors >255
3864 // 4843136: (process) pipe file descriptor from Runtime.exec not being closed
3865 // 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
3866 //
3867 #ifdef FD_CLOEXEC
3868 {
3869 int flags = ::fcntl(fd, F_GETFD);
3870 if (flags != -1) {
3871 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
3872 }
3873 }
3874 #endif
3875
3876 return fd;
3877 }
3878
3879
3880 // create binary file, rewriting existing file if required
3881 int os::create_binary_file(const char* path, bool rewrite_existing) {
3882 int oflags = O_WRONLY | O_CREAT;
3883 if (!rewrite_existing) {
3884 oflags |= O_EXCL;
3885 }
3886 return ::open(path, oflags, S_IREAD | S_IWRITE);
3887 }
3888
3889 // return current position of file pointer
3890 jlong os::current_file_offset(int fd) {
3891 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
3892 }
3893
3894 // move file pointer to the specified offset
3895 jlong os::seek_to_file_offset(int fd, jlong offset) {
3896 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
3897 }
3898
3899 // This code originates from JDK's sysAvailable
3900 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
3901
3902 int os::available(int fd, jlong *bytes) {
3903 jlong cur, end;
3904 int mode;
3905 struct stat buf;
3906
3907 if (::fstat(fd, &buf) >= 0) {
3908 mode = buf.st_mode;
3909 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
3910 int n;
3911 if (::ioctl(fd, FIONREAD, &n) >= 0) {
3912 *bytes = n;
3913 return 1;
3914 }
3915 }
3916 }
3917 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
3918 return 0;
3919 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
3920 return 0;
3921 } else if (::lseek(fd, cur, SEEK_SET) == -1) {
3922 return 0;
3923 }
3924 *bytes = end - cur;
3925 return 1;
3926 }
3927
3928 // Map a block of memory.
3929 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
3930 char *addr, size_t bytes, bool read_only,
3931 bool allow_exec) {
3932 int prot;
3933 int flags;
3934
3935 if (read_only) {
3936 prot = PROT_READ;
3937 flags = MAP_SHARED;
3938 } else {
3939 prot = PROT_READ | PROT_WRITE;
3940 flags = MAP_PRIVATE;
3941 }
3942
3943 if (allow_exec) {
3944 prot |= PROT_EXEC;
3945 }
3946
3947 if (addr != NULL) {
3948 flags |= MAP_FIXED;
3949 }
3950
3951 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
3952 fd, file_offset);
3953 if (mapped_address == MAP_FAILED) {
3954 return NULL;
3955 }
3956 return mapped_address;
3957 }
3958
3959
3960 // Remap a block of memory.
3961 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
3962 char *addr, size_t bytes, bool read_only,
3963 bool allow_exec) {
3964 // same as map_memory() on this OS
3965 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
3966 allow_exec);
3967 }
3968
3969
3970 // Unmap a block of memory.
3971 bool os::pd_unmap_memory(char* addr, size_t bytes) {
3972 return munmap(addr, bytes) == 0;
3973 }
3974
3975 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
3976 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
3977 // of a thread.
3978 //
3979 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
3980 // the fast estimate available on the platform.
3981
3982 jlong os::current_thread_cpu_time() {
3983 #ifdef __APPLE__
3984 return os::thread_cpu_time(Thread::current(), true /* user + sys */);
3985 #else
3986 Unimplemented();
3987 return 0;
3988 #endif
3989 }
3990
3991 jlong os::thread_cpu_time(Thread* thread) {
3992 #ifdef __APPLE__
3993 return os::thread_cpu_time(thread, true /* user + sys */);
3994 #else
3995 Unimplemented();
3996 return 0;
3997 #endif
3998 }
3999
4000 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
4001 #ifdef __APPLE__
4002 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
4003 #else
4004 Unimplemented();
4005 return 0;
4006 #endif
4007 }
4008
4009 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
4010 #ifdef __APPLE__
4011 struct thread_basic_info tinfo;
4012 mach_msg_type_number_t tcount = THREAD_INFO_MAX;
4013 kern_return_t kr;
4014 thread_t mach_thread;
4015
4016 mach_thread = thread->osthread()->thread_id();
4017 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
4018 if (kr != KERN_SUCCESS) {
4019 return -1;
4020 }
4021
4022 if (user_sys_cpu_time) {
4023 jlong nanos;
4024 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
4025 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
4026 return nanos;
4027 } else {
4028 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
4029 }
4030 #else
4031 Unimplemented();
4032 return 0;
4033 #endif
4034 }
4035
4036
4037 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4038 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4039 info_ptr->may_skip_backward = false; // elapsed time not wall time
4040 info_ptr->may_skip_forward = false; // elapsed time not wall time
4041 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4042 }
4043
4044 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4045 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
4046 info_ptr->may_skip_backward = false; // elapsed time not wall time
4047 info_ptr->may_skip_forward = false; // elapsed time not wall time
4048 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4049 }
4050
4051 bool os::is_thread_cpu_time_supported() {
4052 #ifdef __APPLE__
4053 return true;
4054 #else
4055 return false;
4056 #endif
4057 }
4058
4059 // System loadavg support. Returns -1 if load average cannot be obtained.
4060 // Bsd doesn't yet have a (official) notion of processor sets,
4061 // so just return the system wide load average.
4062 int os::loadavg(double loadavg[], int nelem) {
4063 return ::getloadavg(loadavg, nelem);
4064 }
4065
4066 void os::pause() {
4067 char filename[MAX_PATH];
4068 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
4069 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
4070 } else {
4071 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
4072 }
4073
4074 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
4075 if (fd != -1) {
4076 struct stat buf;
4077 ::close(fd);
4078 while (::stat(filename, &buf) == 0) {
4079 (void)::poll(NULL, 0, 100);
4080 }
4081 } else {
4082 jio_fprintf(stderr,
4083 "Could not open pause file '%s', continuing immediately.\n", filename);
4084 }
4085 }
4086
4087
4088 // Refer to the comments in os_solaris.cpp park-unpark. The next two
4089 // comment paragraphs are worth repeating here:
4090 //
4091 // Assumption:
4092 // Only one parker can exist on an event, which is why we allocate
4093 // them per-thread. Multiple unparkers can coexist.
4094 //
4095 // _Event serves as a restricted-range semaphore.
4096 // -1 : thread is blocked, i.e. there is a waiter
4097 // 0 : neutral: thread is running or ready,
4098 // could have been signaled after a wait started
4099 // 1 : signaled - thread is running or ready
4100 //
4101 // Beware -- Some versions of NPTL embody a flaw where pthread_cond_timedwait() can
4102 // hang indefinitely. For instance NPTL 0.60 on 2.4.21-4ELsmp is vulnerable.
4103 // For specifics regarding the bug see GLIBC BUGID 261237 :
4104 // http://www.mail-archive.com/debian-glibc@lists.debian.org/msg10837.html.
4105 // Briefly, pthread_cond_timedwait() calls with an expiry time that's not in the future
4106 // will either hang or corrupt the condvar, resulting in subsequent hangs if the condvar
4107 // is used. (The simple C test-case provided in the GLIBC bug report manifests the
4108 // hang). The JVM is vulernable via sleep(), Object.wait(timo), LockSupport.parkNanos()
4109 // and monitorenter when we're using 1-0 locking. All those operations may result in
4110 // calls to pthread_cond_timedwait(). Using LD_ASSUME_KERNEL to use an older version
4111 // of libpthread avoids the problem, but isn't practical.
4112 //
4113 // Possible remedies:
4114 //
4115 // 1. Establish a minimum relative wait time. 50 to 100 msecs seems to work.
4116 // This is palliative and probabilistic, however. If the thread is preempted
4117 // between the call to compute_abstime() and pthread_cond_timedwait(), more
4118 // than the minimum period may have passed, and the abstime may be stale (in the
4119 // past) resultin in a hang. Using this technique reduces the odds of a hang
4120 // but the JVM is still vulnerable, particularly on heavily loaded systems.
4121 //
4122 // 2. Modify park-unpark to use per-thread (per ParkEvent) pipe-pairs instead
4123 // of the usual flag-condvar-mutex idiom. The write side of the pipe is set
4124 // NDELAY. unpark() reduces to write(), park() reduces to read() and park(timo)
4125 // reduces to poll()+read(). This works well, but consumes 2 FDs per extant
4126 // thread.
4127 //
4128 // 3. Embargo pthread_cond_timedwait() and implement a native "chron" thread
4129 // that manages timeouts. We'd emulate pthread_cond_timedwait() by enqueuing
4130 // a timeout request to the chron thread and then blocking via pthread_cond_wait().
4131 // This also works well. In fact it avoids kernel-level scalability impediments
4132 // on certain platforms that don't handle lots of active pthread_cond_timedwait()
4133 // timers in a graceful fashion.
4134 //
4135 // 4. When the abstime value is in the past it appears that control returns
4136 // correctly from pthread_cond_timedwait(), but the condvar is left corrupt.
4137 // Subsequent timedwait/wait calls may hang indefinitely. Given that, we
4138 // can avoid the problem by reinitializing the condvar -- by cond_destroy()
4139 // followed by cond_init() -- after all calls to pthread_cond_timedwait().
4140 // It may be possible to avoid reinitialization by checking the return
4141 // value from pthread_cond_timedwait(). In addition to reinitializing the
4142 // condvar we must establish the invariant that cond_signal() is only called
4143 // within critical sections protected by the adjunct mutex. This prevents
4144 // cond_signal() from "seeing" a condvar that's in the midst of being
4145 // reinitialized or that is corrupt. Sadly, this invariant obviates the
4146 // desirable signal-after-unlock optimization that avoids futile context switching.
4147 //
4148 // I'm also concerned that some versions of NTPL might allocate an auxilliary
4149 // structure when a condvar is used or initialized. cond_destroy() would
4150 // release the helper structure. Our reinitialize-after-timedwait fix
4151 // put excessive stress on malloc/free and locks protecting the c-heap.
4152 //
4153 // We currently use (4). See the WorkAroundNTPLTimedWaitHang flag.
4154 // It may be possible to refine (4) by checking the kernel and NTPL verisons
4155 // and only enabling the work-around for vulnerable environments.
4156
4157 // utility to compute the abstime argument to timedwait:
4158 // millis is the relative timeout time
4159 // abstime will be the absolute timeout time
4160 // TODO: replace compute_abstime() with unpackTime()
4161
4162 static struct timespec* compute_abstime(struct timespec* abstime,
4163 jlong millis) {
4164 if (millis < 0) millis = 0;
4165 struct timeval now;
4166 int status = gettimeofday(&now, NULL);
4167 assert(status == 0, "gettimeofday");
4168 jlong seconds = millis / 1000;
4169 millis %= 1000;
4170 if (seconds > 50000000) { // see man cond_timedwait(3T)
4171 seconds = 50000000;
4172 }
4173 abstime->tv_sec = now.tv_sec + seconds;
4174 long usec = now.tv_usec + millis * 1000;
4175 if (usec >= 1000000) {
4176 abstime->tv_sec += 1;
4177 usec -= 1000000;
4178 }
4179 abstime->tv_nsec = usec * 1000;
4180 return abstime;
4181 }
4182
4183 void os::PlatformEvent::park() { // AKA "down()"
4184 // Transitions for _Event:
4185 // -1 => -1 : illegal
4186 // 1 => 0 : pass - return immediately
4187 // 0 => -1 : block; then set _Event to 0 before returning
4188
4189 // Invariant: Only the thread associated with the Event/PlatformEvent
4190 // may call park().
4191 // TODO: assert that _Assoc != NULL or _Assoc == Self
4192 assert(_nParked == 0, "invariant");
4193
4194 int v;
4195 for (;;) {
4196 v = _Event;
4197 if (Atomic::cmpxchg(v-1, &_Event, v) == v) break;
4198 }
4199 guarantee(v >= 0, "invariant");
4200 if (v == 0) {
4201 // Do this the hard way by blocking ...
4202 int status = pthread_mutex_lock(_mutex);
4203 assert_status(status == 0, status, "mutex_lock");
4204 guarantee(_nParked == 0, "invariant");
4205 ++_nParked;
4206 while (_Event < 0) {
4207 status = pthread_cond_wait(_cond, _mutex);
4208 // for some reason, under 2.7 lwp_cond_wait() may return ETIME ...
4209 // Treat this the same as if the wait was interrupted
4210 if (status == ETIMEDOUT) { status = EINTR; }
4211 assert_status(status == 0 || status == EINTR, status, "cond_wait");
4212 }
4213 --_nParked;
4214
4215 _Event = 0;
4216 status = pthread_mutex_unlock(_mutex);
4217 assert_status(status == 0, status, "mutex_unlock");
4218 // Paranoia to ensure our locked and lock-free paths interact
4219 // correctly with each other.
4220 OrderAccess::fence();
4221 }
4222 guarantee(_Event >= 0, "invariant");
4223 }
4224
4225 int os::PlatformEvent::park(jlong millis) {
4226 // Transitions for _Event:
4227 // -1 => -1 : illegal
4228 // 1 => 0 : pass - return immediately
4229 // 0 => -1 : block; then set _Event to 0 before returning
4230
4231 guarantee(_nParked == 0, "invariant");
4232
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) return OS_OK;
4240
4241 // We do this the hard way, by blocking the thread.
4242 // Consider enforcing a minimum timeout value.
4243 struct timespec abst;
4244 compute_abstime(&abst, millis);
4245
4246 int ret = OS_TIMEOUT;
4247 int status = pthread_mutex_lock(_mutex);
4248 assert_status(status == 0, status, "mutex_lock");
4249 guarantee(_nParked == 0, "invariant");
4250 ++_nParked;
4251
4252 // Object.wait(timo) will return because of
4253 // (a) notification
4254 // (b) timeout
4255 // (c) thread.interrupt
4256 //
4257 // Thread.interrupt and object.notify{All} both call Event::set.
4258 // That is, we treat thread.interrupt as a special case of notification.
4259 // We ignore spurious OS wakeups unless FilterSpuriousWakeups is false.
4260 // We assume all ETIME returns are valid.
4261 //
4262 // TODO: properly differentiate simultaneous notify+interrupt.
4263 // In that case, we should propagate the notify to another waiter.
4264
4265 while (_Event < 0) {
4266 status = pthread_cond_timedwait(_cond, _mutex, &abst);
4267 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4268 pthread_cond_destroy(_cond);
4269 pthread_cond_init(_cond, NULL);
4270 }
4271 assert_status(status == 0 || status == EINTR ||
4272 status == ETIMEDOUT,
4273 status, "cond_timedwait");
4274 if (!FilterSpuriousWakeups) break; // previous semantics
4275 if (status == ETIMEDOUT) break;
4276 // We consume and ignore EINTR and spurious wakeups.
4277 }
4278 --_nParked;
4279 if (_Event >= 0) {
4280 ret = OS_OK;
4281 }
4282 _Event = 0;
4283 status = pthread_mutex_unlock(_mutex);
4284 assert_status(status == 0, status, "mutex_unlock");
4285 assert(_nParked == 0, "invariant");
4286 // Paranoia to ensure our locked and lock-free paths interact
4287 // correctly with each other.
4288 OrderAccess::fence();
4289 return ret;
4290 }
4291
4292 void os::PlatformEvent::unpark() {
4293 // Transitions for _Event:
4294 // 0 => 1 : just return
4295 // 1 => 1 : just return
4296 // -1 => either 0 or 1; must signal target thread
4297 // That is, we can safely transition _Event from -1 to either
4298 // 0 or 1.
4299 // See also: "Semaphores in Plan 9" by Mullender & Cox
4300 //
4301 // Note: Forcing a transition from "-1" to "1" on an unpark() means
4302 // that it will take two back-to-back park() calls for the owning
4303 // thread to block. This has the benefit of forcing a spurious return
4304 // from the first park() call after an unpark() call which will help
4305 // shake out uses of park() and unpark() without condition variables.
4306
4307 if (Atomic::xchg(1, &_Event) >= 0) return;
4308
4309 // Wait for the thread associated with the event to vacate
4310 int status = pthread_mutex_lock(_mutex);
4311 assert_status(status == 0, status, "mutex_lock");
4312 int AnyWaiters = _nParked;
4313 assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant");
4314 if (AnyWaiters != 0 && WorkAroundNPTLTimedWaitHang) {
4315 AnyWaiters = 0;
4316 pthread_cond_signal(_cond);
4317 }
4318 status = pthread_mutex_unlock(_mutex);
4319 assert_status(status == 0, status, "mutex_unlock");
4320 if (AnyWaiters != 0) {
4321 // Note that we signal() *after* dropping the lock for "immortal" Events.
4322 // This is safe and avoids a common class of futile wakeups. In rare
4323 // circumstances this can cause a thread to return prematurely from
4324 // cond_{timed}wait() but the spurious wakeup is benign and the victim
4325 // will simply re-test the condition and re-park itself.
4326 // This provides particular benefit if the underlying platform does not
4327 // provide wait morphing.
4328 status = pthread_cond_signal(_cond);
4329 assert_status(status == 0, status, "cond_signal");
4330 }
4331 }
4332
4333
4334 // JSR166
4335 // -------------------------------------------------------
4336
4337 // The solaris and bsd implementations of park/unpark are fairly
4338 // conservative for now, but can be improved. They currently use a
4339 // mutex/condvar pair, plus a a count.
4340 // Park decrements count if > 0, else does a condvar wait. Unpark
4341 // sets count to 1 and signals condvar. Only one thread ever waits
4342 // on the condvar. Contention seen when trying to park implies that someone
4343 // is unparking you, so don't wait. And spurious returns are fine, so there
4344 // is no need to track notifications.
4345
4346 #define MAX_SECS 100000000
4347
4348 // This code is common to bsd and solaris and will be moved to a
4349 // common place in dolphin.
4350 //
4351 // The passed in time value is either a relative time in nanoseconds
4352 // or an absolute time in milliseconds. Either way it has to be unpacked
4353 // into suitable seconds and nanoseconds components and stored in the
4354 // given timespec structure.
4355 // Given time is a 64-bit value and the time_t used in the timespec is only
4356 // a signed-32-bit value (except on 64-bit Bsd) we have to watch for
4357 // overflow if times way in the future are given. Further on Solaris versions
4358 // prior to 10 there is a restriction (see cond_timedwait) that the specified
4359 // number of seconds, in abstime, is less than current_time + 100,000,000.
4360 // As it will be 28 years before "now + 100000000" will overflow we can
4361 // ignore overflow and just impose a hard-limit on seconds using the value
4362 // of "now + 100,000,000". This places a limit on the timeout of about 3.17
4363 // years from "now".
4364
4365 static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) {
4366 assert(time > 0, "convertTime");
4367
4368 struct timeval now;
4369 int status = gettimeofday(&now, NULL);
4370 assert(status == 0, "gettimeofday");
4371
4372 time_t max_secs = now.tv_sec + MAX_SECS;
4373
4374 if (isAbsolute) {
4375 jlong secs = time / 1000;
4376 if (secs > max_secs) {
4377 absTime->tv_sec = max_secs;
4378 } else {
4379 absTime->tv_sec = secs;
4380 }
4381 absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC;
4382 } else {
4383 jlong secs = time / NANOSECS_PER_SEC;
4384 if (secs >= MAX_SECS) {
4385 absTime->tv_sec = max_secs;
4386 absTime->tv_nsec = 0;
4387 } else {
4388 absTime->tv_sec = now.tv_sec + secs;
4389 absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000;
4390 if (absTime->tv_nsec >= NANOSECS_PER_SEC) {
4391 absTime->tv_nsec -= NANOSECS_PER_SEC;
4392 ++absTime->tv_sec; // note: this must be <= max_secs
4393 }
4394 }
4395 }
4396 assert(absTime->tv_sec >= 0, "tv_sec < 0");
4397 assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs");
4398 assert(absTime->tv_nsec >= 0, "tv_nsec < 0");
4399 assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec");
4400 }
4401
4402 void Parker::park(bool isAbsolute, jlong time) {
4403 // Ideally we'd do something useful while spinning, such
4404 // as calling unpackTime().
4405
4406 // Optional fast-path check:
4407 // Return immediately if a permit is available.
4408 // We depend on Atomic::xchg() having full barrier semantics
4409 // since we are doing a lock-free update to _counter.
4410 if (Atomic::xchg(0, &_counter) > 0) return;
4411
4412 Thread* thread = Thread::current();
4413 assert(thread->is_Java_thread(), "Must be JavaThread");
4414 JavaThread *jt = (JavaThread *)thread;
4415
4416 // Optional optimization -- avoid state transitions if there's an interrupt pending.
4417 // Check interrupt before trying to wait
4418 if (Thread::is_interrupted(thread, false)) {
4419 return;
4420 }
4421
4422 // Next, demultiplex/decode time arguments
4423 struct timespec absTime;
4424 if (time < 0 || (isAbsolute && time == 0)) { // don't wait at all
4425 return;
4426 }
4427 if (time > 0) {
4428 unpackTime(&absTime, isAbsolute, time);
4429 }
4430
4431
4432 // Enter safepoint region
4433 // Beware of deadlocks such as 6317397.
4434 // The per-thread Parker:: mutex is a classic leaf-lock.
4435 // In particular a thread must never block on the Threads_lock while
4436 // holding the Parker:: mutex. If safepoints are pending both the
4437 // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock.
4438 ThreadBlockInVM tbivm(jt);
4439
4440 // Don't wait if cannot get lock since interference arises from
4441 // unblocking. Also. check interrupt before trying wait
4442 if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) {
4443 return;
4444 }
4445
4446 int status;
4447 if (_counter > 0) { // no wait needed
4448 _counter = 0;
4449 status = pthread_mutex_unlock(_mutex);
4450 assert(status == 0, "invariant");
4451 // Paranoia to ensure our locked and lock-free paths interact
4452 // correctly with each other and Java-level accesses.
4453 OrderAccess::fence();
4454 return;
4455 }
4456
4457 #ifdef ASSERT
4458 // Don't catch signals while blocked; let the running threads have the signals.
4459 // (This allows a debugger to break into the running thread.)
4460 sigset_t oldsigs;
4461 sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals();
4462 pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs);
4463 #endif
4464
4465 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
4466 jt->set_suspend_equivalent();
4467 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
4468
4469 if (time == 0) {
4470 status = pthread_cond_wait(_cond, _mutex);
4471 } else {
4472 status = pthread_cond_timedwait(_cond, _mutex, &absTime);
4473 if (status != 0 && WorkAroundNPTLTimedWaitHang) {
4474 pthread_cond_destroy(_cond);
4475 pthread_cond_init(_cond, NULL);
4476 }
4477 }
4478 assert_status(status == 0 || status == EINTR ||
4479 status == ETIMEDOUT,
4480 status, "cond_timedwait");
4481
4482 #ifdef ASSERT
4483 pthread_sigmask(SIG_SETMASK, &oldsigs, NULL);
4484 #endif
4485
4486 _counter = 0;
4487 status = pthread_mutex_unlock(_mutex);
4488 assert_status(status == 0, status, "invariant");
4489 // Paranoia to ensure our locked and lock-free paths interact
4490 // correctly with each other and Java-level accesses.
4491 OrderAccess::fence();
4492
4493 // If externally suspended while waiting, re-suspend
4494 if (jt->handle_special_suspend_equivalent_condition()) {
4495 jt->java_suspend_self();
4496 }
4497 }
4498
4499 void Parker::unpark() {
4500 int status = pthread_mutex_lock(_mutex);
4501 assert(status == 0, "invariant");
4502 const int s = _counter;
4503 _counter = 1;
4504 if (s < 1) {
4505 if (WorkAroundNPTLTimedWaitHang) {
4506 status = pthread_cond_signal(_cond);
4507 assert(status == 0, "invariant");
4508 status = pthread_mutex_unlock(_mutex);
4509 assert(status == 0, "invariant");
4510 } else {
4511 status = pthread_mutex_unlock(_mutex);
4512 assert(status == 0, "invariant");
4513 status = pthread_cond_signal(_cond);
4514 assert(status == 0, "invariant");
4515 }
4516 } else {
4517 pthread_mutex_unlock(_mutex);
4518 assert(status == 0, "invariant");
4519 }
4520 }
4521
4522
4523 // Darwin has no "environ" in a dynamic library.
4524 #ifdef __APPLE__
4525 #include <crt_externs.h>
4526 #define environ (*_NSGetEnviron())
4527 #else
4528 extern char** environ;
4529 #endif
4530
4531 // Run the specified command in a separate process. Return its exit value,
4532 // or -1 on failure (e.g. can't fork a new process).
4533 // Unlike system(), this function can be called from signal handler. It
4534 // doesn't block SIGINT et al.
4535 int os::fork_and_exec(char* cmd) {
4536 const char * argv[4] = {"sh", "-c", cmd, NULL};
4537
4538 // fork() in BsdThreads/NPTL is not async-safe. It needs to run
4539 // pthread_atfork handlers and reset pthread library. All we need is a
4540 // separate process to execve. Make a direct syscall to fork process.
4541 // On IA64 there's no fork syscall, we have to use fork() and hope for
4542 // the best...
4543 pid_t pid = fork();
4544
4545 if (pid < 0) {
4546 // fork failed
4547 return -1;
4548
4549 } else if (pid == 0) {
4550 // child process
4551
4552 // execve() in BsdThreads will call pthread_kill_other_threads_np()
4553 // first to kill every thread on the thread list. Because this list is
4554 // not reset by fork() (see notes above), execve() will instead kill
4555 // every thread in the parent process. We know this is the only thread
4556 // in the new process, so make a system call directly.
4557 // IA64 should use normal execve() from glibc to match the glibc fork()
4558 // above.
4559 execve("/bin/sh", (char* const*)argv, environ);
4560
4561 // execve failed
4562 _exit(-1);
4563
4564 } else {
4565 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
4566 // care about the actual exit code, for now.
4567
4568 int status;
4569
4570 // Wait for the child process to exit. This returns immediately if
4571 // the child has already exited. */
4572 while (waitpid(pid, &status, 0) < 0) {
4573 switch (errno) {
4574 case ECHILD: return 0;
4575 case EINTR: break;
4576 default: return -1;
4577 }
4578 }
4579
4580 if (WIFEXITED(status)) {
4581 // The child exited normally; get its exit code.
4582 return WEXITSTATUS(status);
4583 } else if (WIFSIGNALED(status)) {
4584 // The child exited because of a signal
4585 // The best value to return is 0x80 + signal number,
4586 // because that is what all Unix shells do, and because
4587 // it allows callers to distinguish between process exit and
4588 // process death by signal.
4589 return 0x80 + WTERMSIG(status);
4590 } else {
4591 // Unknown exit code; pass it through
4592 return status;
4593 }
4594 }
4595 }
4596
4597 // is_headless_jre()
4598 //
4599 // Test for the existence of xawt/libmawt.so or libawt_xawt.so
4600 // in order to report if we are running in a headless jre
4601 //
4602 // Since JDK8 xawt/libmawt.so was moved into the same directory
4603 // as libawt.so, and renamed libawt_xawt.so
4604 //
4605 bool os::is_headless_jre() {
4606 #ifdef __APPLE__
4607 // We no longer build headless-only on Mac OS X
4608 return false;
4609 #else
4610 struct stat statbuf;
4611 char buf[MAXPATHLEN];
4612 char libmawtpath[MAXPATHLEN];
4613 const char *xawtstr = "/xawt/libmawt" JNI_LIB_SUFFIX;
4614 const char *new_xawtstr = "/libawt_xawt" JNI_LIB_SUFFIX;
4615 char *p;
4616
4617 // Get path to libjvm.so
4618 os::jvm_path(buf, sizeof(buf));
4619
4620 // Get rid of libjvm.so
4621 p = strrchr(buf, '/');
4622 if (p == NULL) {
4623 return false;
4624 } else {
4625 *p = '\0';
4626 }
4627
4628 // Get rid of client or server
4629 p = strrchr(buf, '/');
4630 if (p == NULL) {
4631 return false;
4632 } else {
4633 *p = '\0';
4634 }
4635
4636 // check xawt/libmawt.so
4637 strcpy(libmawtpath, buf);
4638 strcat(libmawtpath, xawtstr);
4639 if (::stat(libmawtpath, &statbuf) == 0) return false;
4640
4641 // check libawt_xawt.so
4642 strcpy(libmawtpath, buf);
4643 strcat(libmawtpath, new_xawtstr);
4644 if (::stat(libmawtpath, &statbuf) == 0) return false;
4645
4646 return true;
4647 #endif
4648 }
4649
4650 // Get the default path to the core file
4651 // Returns the length of the string
4652 int os::get_core_path(char* buffer, size_t bufferSize) {
4653 int n = jio_snprintf(buffer, bufferSize, "/cores/core.%d", current_process_id());
4654
4655 // Truncate if theoretical string was longer than bufferSize
4656 n = MIN2(n, (int)bufferSize);
4657
4658 return n;
4659 }
4660
4661 #ifndef PRODUCT
4662 void TestReserveMemorySpecial_test() {
4663 // No tests available for this platform
4664 }
4665 #endif