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